JP2016190637A - Measuring apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a measuring apparatus which measures propulsion power and power loss in an easy method.SOLUTION: A measuring apparatus includes: a first detection circuit 373a connected with a first strain gauge 369a and a second strain gauge 369b which are provided so that detection directions are arranged parallel to a longitudinal direction of a crank 105, the first detection circuit 373a being a bridge circuit that detects bending deformation x occurring in the crank 105; and a second detection circuit 373b connected with a third strain gauge 369c, which is provided so that a detection direction is arranged parallel to the longitudinal direction of the crank 105, and a fourth strain gauge 369d, which is provided so that a detection direction is arranged perpendicular to the longitudinal direction of the crank 105, the second detection circuit 373b being a bridge circuit which detects bending deformation y and tensile deformation z occurring in the crank 105.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a measuring device for measuring a force applied to a human-powered machine having a crank.

  2. Description of the Related Art Conventionally, there is a device that is attached to a bicycle and calculates and displays information related to the traveling of the bicycle, information related to the exercise of the driver, and the like. This type of device calculates and displays predetermined information by receiving data from a sensor provided on the bicycle. The information to be displayed includes a force (torque or the like) applied to the pedal by the driver. As a method for measuring this type of force, for example, Patent Document 1 discloses a technique for measuring the crankshaft strain and detecting the torque applied to the crank.

  Patent Document 2 discloses a technique in which a piezoelectric sensor is embedded in a crank and torque is measured by a voltage generated by crank distortion.

  Further, Patent Document 1 describes that it can be applied to a stationary bicycle health machine (also called a bicycle ergometer or a fitness bike).

  As described above, in a human-powered machine equipped with a crank, it is already known to measure a torque and calculate a momentum or the like by detecting a strain applied to the crank.

Japanese Patent Laid-Open No. 10-35567 JP 2009-6991 A

  In the bicycle meter described in Patent Document 1, since it is necessary to install a sensor in the bottom bracket portion, there is a problem that frame processing is required for the bottom bracket and further knurling processing is required for the crankshaft.

  Moreover, in the bicycle part provided with the instrument described in Patent Document 2, not only the torque due to the force in the rotational direction but also the loss force is detected, and how much force is the rotational force, that is, the propulsive force. There was a problem that it was not possible to know exactly.

  In view of the above-described problems, an object of the present invention is to provide a measuring device that can measure propulsive force and loss force by a simple method, for example.

  In order to solve the above problems, the invention described in claim 1 is a first detection circuit that detects a rotational direction distortion generated in a direction in which a crank of a human-powered machine rotates, and the direction in which the crank rotates. Measures the propulsive force of the human-powered machine based on the detection result of the first detection circuit and the second detection circuit that detects another direction strain generated in another direction, and the detection result of the second detection circuit And a control unit that measures a loss force of the manpower machine based on the control device.

It is explanatory drawing which shows the whole structure of the bicycle concerning the 1st Example of this invention. It is explanatory drawing which showed the positional relationship of the cycle computer shown in FIG. 1, a measurement module, and a cadence sensor. FIG. 2 is a block configuration diagram of a cycle computer, a measurement module, and a cadence sensor shown in FIG. 1. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 4 is a circuit diagram of a measurement module strain detection circuit shown in FIG. 3. It is explanatory drawing of the force added to a right side crank, and a deformation | transformation. It is a flowchart of a process of the cadence sensor shown in FIG. It is a flowchart of a process of the measurement module and cycle computer shown by FIG. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning 2nd Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 10 is a circuit diagram of the measurement module strain detection circuit shown in FIG. 9. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning 3rd Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 13 is a circuit diagram of the measurement module strain detection circuit shown in FIG. 12. It is a block block diagram of the cycle computer, measurement module, and cadence sensor concerning the 4th example of the present invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 16 is a circuit diagram of the measurement module strain detection circuit shown in FIG. 15. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning the 5th Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 19 is a circuit diagram of the measurement module strain detection circuit shown in FIG. 18. It is explanatory drawing in case a 1st strain gauge and a 2nd strain gauge deform | transform by bending deformation x. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning the 6th Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. It is a circuit diagram of the measurement module distortion | strain detection circuit shown by FIG. FIG. 23 is a circuit diagram of another embodiment of the measurement module strain detection circuit shown in FIG. 22. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning the 7th Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 27 is a circuit diagram of a measurement module strain detection circuit shown in FIG. 26. It is a block block diagram of the cycle computer, the measurement module, and cadence sensor concerning the 8th Example of this invention. It is explanatory drawing of arrangement | positioning to the crank of the strain gauge shown by FIG. FIG. 30 is a circuit diagram of the measurement module strain detection circuit shown in FIG. 29.

  Hereinafter, a measuring apparatus according to an embodiment of the present invention will be described. A measurement apparatus according to an embodiment of the present invention includes a first strain gauge, a second strain gauge, and a second strain gauge provided on a side surface that is a plane of a crank parallel to a plane including a circle defined by a rotational motion of a crank of a human-powered machine. A first strain circuit connected to the third strain gauge and the fourth strain gauge, the first strain gauge and the second strain gauge, and detecting a rotational strain generated in the direction of rotation of the crank; a third strain gauge; A fourth strain gauge is connected to detect at least one of inward and outward strain generated in a direction perpendicular to the plane of the crank and tensile strain generated in a direction parallel to the longitudinal direction of the crank. And a second detection circuit. The first strain gauge to the third strain gauge are provided so that the detection direction is parallel to the longitudinal direction of the crank, and the fourth strain gauge is perpendicular to the longitudinal direction of the crank. It is provided as follows. By doing so, the propulsive force and the loss force applied to the crank are measured from the rotational strain detected by the first detection circuit and the internal / external strain or tensile strain detected by the second detection circuit. Can do. Therefore, propulsive force and loss force can be measured by a simple method. In addition, since the first to fourth strain gauges are provided only on the side surface of the crank, the propulsive force and the loss force can be measured with only one surface, and by providing the inner surface side of the side surface, There is no interference with the driver's feet.

  Moreover, you may have a correction | amendment means which correct | amends the distortion component mixed other than the distortion which each detection circuit detects based on the output of a 1st detection circuit and the output of a 2nd detection circuit. By doing in this way, the influence of distortion other than the detection target contained in the output of the 1st detection circuit or the 2nd detection circuit can be excluded.

  Moreover, the 1st strain gauge and the 2nd strain gauge may be provided so that it may become symmetrical with respect to the central axis of the longitudinal direction of a crank side surface. By doing in this way, a rotation direction distortion | strain can be detected accurately.

  Further, the third strain gauge and the fourth strain gauge may be overlapped with each other. By doing in this way, the size of the strain gauge provided in the crank can be reduced.

  In addition, the first detection circuit and the second detection circuit are configured by a bridge circuit, and the first strain gauge and the second strain gauge are connected in series to the power source in the bridge circuit configuring the first detection circuit, and the third The strain gauge and the fourth strain gauge are connected in series to the power supply in the bridge circuit constituting the second detection circuit, and further the bridge circuit constituting the first detection circuit and the bridge circuit constituting the second detection circuit Resistive elements other than the first to fourth strain gauges may be configured with fixed resistors. Thus, the bridge circuit can detect rotational strain, inward / outward strain, or tensile strain, and can measure propulsive force and loss force with a simple circuit configuration.

  Further, the fixed resistor may be shared by the first detection circuit and the second detection circuit. By doing so, the first detection circuit and the second detection circuit can be practically made into one circuit, and the circuit can be further simplified.

  Moreover, the measuring apparatus concerning other embodiment is the 1st strain gauge provided in the side surface which is a surface of a crank parallel to the plane containing the circle | round | yen defined by the rotational motion of the crank of a human-powered machine, a 2nd strain gauge, A third strain gauge, a fourth strain gauge, a fifth strain gauge, a sixth strain gauge, a seventh strain gauge, an eighth strain gauge, the first strain gauge, the second strain gauge, the fifth strain gauge, and the A first detection circuit connected to a sixth strain gauge and detecting a rotational strain generated in the direction of rotation of the crank; a third strain gauge, a fourth strain gauge, a seventh strain gauge, and an eighth strain gauge; Connected, inward and outward strain occurring in a direction perpendicular to the plane of the crank, or tensile direction thread occurring in a direction parallel to the longitudinal direction of the crank. It has a second detection circuit for detecting at least one of body, the. The first strain gauge, the second strain gauge, the third strain gauge, and the eighth strain gauge are provided so that the detection direction is parallel to the longitudinal direction of the crank, and the fourth strain gauge and the fifth strain gauge. The sixth strain gauge and the seventh strain gauge are provided so that the detection direction is perpendicular to the longitudinal direction of the crank. By doing so, the propulsive force and the loss force applied to the crank are measured from the rotational strain detected by the first detection circuit and the internal / external strain or tensile strain detected by the second detection circuit. Can do. Therefore, propulsive force and loss force can be measured by a simple method. In addition, since the first to eighth strain gauges are provided only on the side surface of the crank, the propulsive force and the loss force can be measured with only one surface. There is no interference with the feet of other people. Further, since the first strain gauge to the fourth strain gauge are connected to the first detection circuit and the rotational strain is detected, the detected rotational strain voltage value is increased and the influence of noise is reduced. can do.

  Further, the first strain gauge, the sixth strain gauge, the second strain gauge, and the fifth strain gauge are respectively connected to diagonal positions in the bridge circuit that constitutes the first detection circuit, and the third strain gauge and the eighth strain gauge. The gauge, the fourth strain gauge, and the seventh strain gauge may be connected to diagonal positions in the bridge circuit that constitutes the second detection circuit. Thus, the bridge circuit can detect rotational strain, inward / outward strain, or tensile strain, and can measure propulsive force and loss force with a simple circuit configuration.

  In addition, the measuring method according to the embodiment of the present invention has a detection direction with respect to the longitudinal direction of the crank on a side surface that is a plane of the crank parallel to a plane including a circle defined by the rotational motion of the crank of the human-powered machine. A first strain gauge, a second strain gauge, and a third strain gauge that are provided in parallel, a fourth strain gauge that is provided so that a detection direction is perpendicular to a longitudinal direction of the crank, The first strain gauge and the second strain gauge are connected, the first detection circuit for detecting the rotational strain generated in the rotating direction of the crank, the third strain gauge and the fourth strain gauge are connected, and the crank At least one of inward and outward strain generated in a direction perpendicular to the plane and tensile strain generated in a direction parallel to the longitudinal direction of the crank In a process performed by a measuring device having a second detection circuit to detect, a rotational direction strain detection step for causing the first detection circuit to detect the rotational direction strain, and a rotational direction strain detected in the rotational direction strain detection step. A propulsive force measuring step for measuring the propulsive force on the basis, an internal / external strain or tensile strain detection step for causing the second detection circuit to detect at least one of an internal / external strain or a tensile strain, and an internal / external strain or tension. A loss force measuring step of measuring the loss force based on at least one of the inner and outer direction strain and the tensile direction strain detected in the directional strain detection step. By doing so, the propulsive force and the loss force applied to the crank are measured from the rotational strain detected by the first detection circuit and the internal / external strain or tensile strain detected by the second detection circuit. Can do. Therefore, propulsive force and loss force can be measured by a simple method. In addition, since the first to fourth strain gauges are provided only on the side surface of the crank, propulsive force and loss force can be measured with only one surface, and by providing the inner surface of the side surface, operation is possible. There is no interference with the feet of other people.

  In addition, the measuring method according to another embodiment of the present invention includes a detection direction with respect to a longitudinal direction of the crank on a side surface that is a plane of the crank parallel to a plane including a circle defined by the rotational motion of the crank of the human-powered machine. Are provided so that the detection direction is perpendicular to the longitudinal direction of the crank, and the first strain gauge, the second strain gauge, the third strain gauge, and the eighth strain gauge. The fourth strain gauge, the fifth strain gauge, the sixth strain gauge, the seventh strain gauge, the first strain gauge, the second strain gauge, the fifth strain gauge, and the sixth strain gauge are connected, and the crank rotates. A first detection circuit for detecting the generated rotational strain, and a third strain gauge, a fourth strain gauge, a seventh strain gauge, and an eighth strain gauge; A second detection circuit for detecting at least one of an inward and outward strain generated in a direction perpendicular to the plane of the rank and a tensile strain generated in a direction parallel to the longitudinal direction of the crank. In the processing performed by the measuring device, the rotational direction strain detecting step for causing the first detection circuit to detect the rotational direction strain, and the propulsive force measurement for measuring the propulsive force based on the rotational direction strain detected in the rotational direction strain detecting step Internal / external strain or tensile strain detection process that causes the second detection circuit to detect at least one of internal / external strain or tensile strain, and internal / external strain detected by the internal / external strain or tensile strain detection step. Or a loss force measurement step for measuring the loss force based on at least one of the strains in the tensile direction; And Nde. By doing so, the propulsive force and the loss force applied to the crank are measured from the rotational strain detected by the first detection circuit and the internal / external strain or tensile strain detected by the second detection circuit. Can do. Therefore, propulsive force and loss force can be measured by a simple method. In addition, since the first to eighth strain gauges are provided only on the side surface of the crank, the propulsive force and the loss force can be measured with only one surface. There is no interference with the feet of other people. Further, since the first detection circuit is connected to the first strain gauge to the fourth strain gauge to detect the rotational strain, the detected rotational strain voltage value is increased and the influence of noise is reduced. be able to.

  A bicycle 1 including a measurement module 301 as a measurement apparatus according to a first embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, the bicycle 1 includes a frame 3, a front wheel 5, a rear wheel 7, a handle 9, a saddle 11, a front fork 13, and a drive mechanism 101.

  The frame 3 is composed of two truss structures. The frame 3 is rotatably connected to the rear wheel 7 at the rear end portion. A front fork 13 is rotatably connected in front of the frame 3.

  The front fork 13 is connected to the handle 9. The front fork 13 and the front wheel 5 are rotatably connected at the front end position of the front fork 13 in the downward direction.

  The front wheel 5 has a hub part, a spoke part, and a tire part. The hub portion is rotatably connected to the front fork 13. And this hub part and the tire part are connected by the spoke part.

  The rear wheel 7 has a hub part, a spoke part, and a tire part. The hub portion is rotatably connected to the frame 3. And this hub part and the tire part are connected by the spoke part. The hub portion of the rear wheel 7 is connected to a sprocket 113 described later.

  The bicycle 1 has a drive mechanism 101 that converts a stepping force by a user's (driver's) foot into a driving force of the bicycle 1. The drive mechanism 101 includes a pedal 103, a crank mechanism 104, a chain ring 109, a chain 111, and a sprocket 113.

  The pedal 103 is a part in contact with a foot for the user to step on. The pedal 103 is supported so as to be rotatable by a pedal crankshaft 115 of the crank mechanism 104.

  The crank mechanism 104 includes a crank 105, a crankshaft 107, and a pedal crankshaft 115 (see FIGS. 2 and 6).

  The crankshaft 107 passes through the frame 3 in the left-right direction (from one side of the bicycle side to the other). The crankshaft 107 is rotatably supported by the frame 3.

  The crank 105 is provided at a right angle to the crankshaft 107. The crank 105 is connected to the crankshaft 107 at one end.

  The pedal crankshaft 115 is provided at a right angle to the crank 105. The axial direction of the pedal crankshaft 115 is the same as that of the crankshaft 107. The pedal crankshaft 115 is connected to the crank 105 at the other end of the crank 105.

  The crank mechanism 104 has such a structure on the side opposite to the side surface of the bicycle 1. That is, the crank mechanism 104 has two cranks 105 and two pedal crankshafts 115. Therefore, the pedal 103 is also provided on each side of the bicycle 1.

  When distinguishing whether these are on the right side or the left side of the bicycle 1, they are described as a right crank 105R, a left crank 105L, a right pedal crankshaft 115R, a left pedal crankshaft 115L, a right pedal 103R, and a left pedal 103L, respectively. To do.

  The right crank 105R and the left crank 105L are connected so as to extend in opposite directions around the crankshaft 107. The right pedal crankshaft 115R, the crankshaft 107, and the left pedal crankshaft 115L are formed in parallel and on the same plane. The right crank 105R and the left crank 105L are formed in parallel and on the same plane.

  The chain ring 109 is connected to the crankshaft 107. The chain ring 109 is preferably constituted by a variable gear capable of changing the gear ratio. A chain 111 is engaged with the chain ring 109.

  The chain 111 is engaged with the chain ring 109 and the sprocket 113. The sprocket 113 is connected to the rear wheel 7. The sprocket 113 is preferably composed of a variable gear.

  The bicycle 1 uses the drive mechanism 101 to convert the user's stepping force into the rotational force of the rear wheels.

  The bicycle 1 includes a cycle computer 201, a measurement module 301, and a cadence sensor 501.

  The cycle computer 201 is disposed on the handle 9. As shown in FIG. 2, the cycle computer 201 includes a cycle computer display unit 203 that displays various types of information and a cycle computer operation unit 205 that receives user operations.

  The various types of information displayed on the cycle computer display unit 203 include the speed of the bicycle 1, position information, the distance to the destination, the estimated arrival time to the destination, the travel distance since the departure, and the elapsed time since the departure. Time, propulsion, loss power, etc.

  Here, the propulsive force is the magnitude of the force applied in the rotation direction of the crank 105. On the other hand, the loss force is a magnitude of a force applied in a direction different from the rotation direction of the crank 105. The force applied in a direction different from the rotational direction is a useless force that does not contribute to the driving of the bicycle 1. Therefore, the user can drive the bicycle 1 more efficiently by increasing the propulsive force as much as possible and decreasing the loss force as much as possible.

  The cycle computer operation unit 205 is shown as a push button in FIG. 2, but is not limited thereto, and various input means such as a touch panel or a plurality of input means can be used in combination.

  The cycle computer 201 includes a cycle computer cadence wireless reception unit 207 and a cycle computer wireless reception unit 209. The cycle computer cadence wireless reception unit 207 and the cycle computer wireless reception unit 209 are connected to the main body portion of the cycle computer 201 through wiring. Note that the cycle computer cadence wireless reception unit 207 and the cycle computer wireless reception unit 209 need not have a reception-only function. For example, you may have a function as a transmission part. Hereinafter, an apparatus described as a transmission unit or a reception unit may also have both a reception function and a transmission function.

  The cadence sensor 501 has a magnetic sensor 505 that detects the approach of a magnet 503 provided on the crank 105 (see FIG. 3). The magnetic sensor 505 detects the position of the magnet 503 by being turned on by the approaching magnet 503. That is, when the magnetic sensor 505 is turned on, the crank 105 is also present at the position where the magnetic sensor 505 is present. From this cadence sensor 501, the cycle computer 201 can obtain cadence [rpm].

  The measurement module 301 is provided on the inner surface of the crank 105 and detects a human force applied to the pedal 103 by a user using a strain gauge 369 (see FIGS. 3 and 4) composed of a plurality of strain gauge elements. Specifically, a propulsive force that is the rotational force of the crank 105 and serves as the driving force of the bicycle 1 and a loss force that is a force applied in a direction different from the rotational direction are calculated.

  FIG. 3 is a block diagram of the cycle computer 201, the measurement module 301, and the cadence sensor 501.

  First, the block configuration of the cadence sensor 501 will be described. The cadence sensor 501 includes a magnetic sensor 505, a cadence sensor wireless transmission unit 507, a cadence sensor control unit 551, a cadence sensor storage unit 553, and a cadence sensor timer 561.

  The magnetic sensor 505 is switched ON / OFF when the magnet 503 approaches. When the magnetic sensor 505 is turned on, the magnetic sensor 505 outputs an information signal indicating that to the cadence sensor control unit 551.

  The cadence sensor wireless transmission unit 507 transmits the cadence information stored in the cadence sensor storage unit 553 to the cycle computer cadence wireless reception unit 207. The transmission by the cadence sensor wireless transmission unit 507 is performed, for example, every second by an instruction from the cadence sensor timer 561. Alternatively, a determination based on the value of the cadence sensor timer 561 is performed by the cadence sensor control unit 551, and based on the determination, transmission by the cadence sensor wireless transmission unit 507 is performed according to a command from the cadence sensor control unit 551. good.

  The cadence sensor control unit 551 comprehensively controls the cadence sensor 501. When the cadence sensor control unit 551 receives an output of an information signal indicating that the magnetic sensor 505 is turned on, the cadence sensor control unit 551 performs the following operation. The cadence sensor control unit 551 instructs the cadence sensor timer 561 to output timer value information. When the cadence sensor control unit 551 receives timer value information from the cadence sensor timer 561, the cadence sensor control unit 551 calculates cadence from the timer value information. Specifically, the time (cycle) [seconds] at which the magnetic sensor 505 is turned on is calculated by multiplying the count value (C) of the timer value information by one count interval (T). Then, cadence [rpm] is calculated by dividing 60 by this period.

  Further, the cadence sensor control unit 551 stores the cadence information in a cadence sensor RAM 555 (described later) of the cadence sensor storage unit 553. The cadence sensor control unit 551 outputs a counter value reset command to the cadence sensor timer 561. The cadence sensor control unit 551 may cause the cadence sensor wireless transmission unit 507 to transmit the cadence information stored in the cadence sensor storage unit 553, for example, at an interval of 1 second.

  Various information is stored in the cadence sensor storage unit 553. The various information is, for example, a control program of the cadence sensor control unit 551 and temporary information required when the cadence sensor control unit 551 performs control. In particular, in this embodiment, the timer value of the cadence sensor timer 561 that is an interval at which the magnetic sensor 505 is turned on is stored. The cadence sensor storage unit 553 includes a cadence sensor RAM 555 and a cadence sensor ROM 557. The cadence sensor RAM 555 stores timer values and the like, and the cadence sensor ROM 557 stores control programs and the like.

  The cadence sensor timer 561 is a timer counter and always counts a clock having a predetermined cycle. When the cadence sensor timer 561 receives a value output command from the cadence sensor control unit 551, the cadence sensor timer 561 outputs timer value information to the cadence sensor control unit 551. When the cadence sensor timer 561 receives a reset command from the cadence sensor control unit 551, the cadence sensor timer 561 resets the value of the timer counter to an initial value. Furthermore, the cadence sensor timer 561 also has a role of instructing the cadence sensor wireless transmission unit 507 to transmit timing. Specifically, for example, the transmission timing is commanded to the cadence sensor wireless transmission unit 507 every second.

  Next, the block configuration of the measurement module 301 will be described. As shown in FIG. 3, the measurement module 301 includes a measurement module wireless transmission unit 309, a measurement module timer 361, a measurement module control unit 351, a measurement module storage unit 353, a measurement module A / D 363, a measurement module strain detection circuit 365, and A strain gauge 369 is provided.

  The measurement module wireless transmission unit 309 transmits the propulsive force and loss force information calculated from the strain information by the measurement module control unit 351 to the cycle computer wireless reception unit 209. Transmission by the measurement module wireless transmission unit 309 is performed, for example, every second by being commanded by the measurement module timer 361. Alternatively, the measurement module control unit 351 may transmit a command based on the value of the measurement module timer 361.

  The measurement module timer 361 is a timer counter and always counts a clock having a predetermined period. Furthermore, the measurement module timer 361 also has a role of instructing the measurement module wireless transmission unit 309 to transmit timing. Specifically, for example, the transmission timing is commanded to the measurement module wireless transmission unit 309 every second.

  The measurement module control unit 351 comprehensively controls the measurement module 301. The measurement module control unit 351 calculates the propulsive force and the loss force from the strain information. The calculation method will be described later.

  Various information is stored in the measurement module storage unit 353. The various types of information are, for example, a control program for the measurement module control unit 351 and temporary information required when the measurement module control unit 351 performs control. In particular, in this embodiment, strain information is stored. The measurement module storage unit 353 includes a measurement module RAM 355 and a measurement module ROM 357. The measurement module RAM 355 stores strain information and the like. The measurement module ROM 357 stores a control program and various parameters, constants, and the like for calculating propulsive force and loss force from strain information.

  The strain gauge 369 is bonded to the crank 105 and integrated. The strain gauge 369 includes a first strain gauge 369a, a second strain gauge 369b, a third strain gauge 369c, and a fourth strain gauge 369d. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 4 shows an arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. Although not shown in FIG. 4, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. The upper surface 117 of the crank 105 is one of the surfaces extending in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 and orthogonal to the inner surface 119 and the outer surface 120. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a and the second strain gauge 369b have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119 and symmetrical to the central axis C1 of the inner surface 119. It is provided to become. The third strain gauge 369c is provided on the central axis C1, and the detection direction is parallel to the central axis C1, and is provided between the first strain gauge 369a and the second strain gauge 369b. The fourth strain gauge 369d is provided on the central axis C1 in the detection direction perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C1 of the inner surface 119.

  That is, the direction parallel to the central axis C1 (the vertical direction in FIG. 4) that is the axis extending in the longitudinal direction of the crank 105, that is, the direction parallel to the longitudinal direction of the crank 105 is the first strain gauge 369a, the second The detection direction of the strain gauge 369b and the third strain gauge 369c is the detection direction of the fourth strain gauge 369d in the direction perpendicular to the central axis C1 (the lateral direction in FIG. 4), that is, the direction perpendicular to the longitudinal direction of the crank 105. It becomes. Accordingly, the detection directions of the first strain gauge 369a to the third strain gauge 369c and the fourth strain gauge 369d are orthogonal to each other.

  In addition, arrangement | positioning of the 1st strain gauge 369a thru | or the 4th strain gauge 369d is not restricted to FIG. In other words, other arrangements may be used as long as a parallel or vertical relationship with the central axis C1 is maintained. However, the first strain gauge 369a and the second strain gauge 369b are arranged symmetrically across the central axis C1, and the third strain gauge 369c and the fourth strain gauge 369d are arranged on the central axis C1, as will be described later. This is preferable because each deformation can be detected with high accuracy.

  In FIG. 4, the crank 105 is described as a simple rectangular parallelepiped, but the corners may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel or vertical) with the center axis C1 is shifted.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, and the fourth strain gauge 369d, and outputs the strain amount of the strain gauge 369 as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a and a second detection circuit 373b that are two bridge circuits. On the first system side of the first detection circuit 373a, the first strain gauge 369a and the second strain gauge 369b are connected in this order from the power source Vcc. That is, the first strain gauge 369a and the second strain gauge 369b are connected in series with the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc. On the first system side of the second detection circuit 373b, the third strain gauge 369c and the fourth strain gauge 369d are connected in this order from the power source Vcc. That is, the third strain gauge 369c and the fourth strain gauge 369d are connected in series with the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc.

  That is, the two fixed resistors R are shared by the first detection circuit 373a and the second detection circuit 373b. Here, the two fixed resistors R have the same resistance value. The two fixed resistors R have the same resistance value as that before the compression or expansion of the strain gauge 369 occurs. The first strain gauge 369a to the fourth strain gauge 369d have the same resistance value.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a, the second strain gauge 369b, and the third strain gauge 369c are parallel to the central axis C1, The fourth strain gauge 369d is in a direction perpendicular to the central axis C1. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first detection circuit 373a using the strain gauge 369 having such characteristics is not compressed or expanded in the detection direction of the first strain gauge 369a and the second strain gauge 369b, the first detection gauge 369a and the first strain gauge 369a The potential difference between the potential Vab between the two strain gauges 369b and the potential Vr between the two fixed resistors R is almost zero.

  When the first strain gauge 369a is compressed and the second strain gauge 369b is expanded, the resistance value of the first strain gauge 369a decreases and the resistance value of the second strain gauge 369b increases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a is expanded and the second strain gauge 369b is compressed, the resistance value of the first strain gauge 369a increases and the resistance value of the second strain gauge 369b decreases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a and the second strain gauge 369b are compressed, the resistance value of both the first strain gauge 369a and the second strain gauge 369b decreases, so the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a and the second strain gauge 369b are extended, the resistance value of both the first strain gauge 369a and the second strain gauge 369b increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  The second detection circuit 373b operates similarly to the first detection circuit 373a. That is, when the third strain gauge 369c is compressed and the fourth strain gauge 369d is expanded, the potential Vcd is increased, the potential Vr is decreased, and a potential difference is generated between the potential Vcd and the potential Vr. When the third strain gauge 369c is expanded and the fourth strain gauge 369d is compressed, the potential Vcd is decreased, the potential Vr is increased, and a potential difference is generated between the potential Vcd and the potential Vr. When both the third strain gauge 369c and the fourth strain gauge 369d are compressed and when both the third strain gauge 369c and the fourth strain gauge 369d are expanded, the potential difference between the potential Vcd and the potential Vr becomes almost zero. .

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a and the second strain gauge 369b where the potential Vab of the first detection circuit 373a can be measured, and a connection point between the two fixed resistors R capable of measuring the potential Vr. The output of 373a (hereinafter referred to as A output). The connection point between the third strain gauge 369c and the fourth strain gauge 369d that can measure the potential Vcd of the second detection circuit 373b, and the connection point of the two fixed resistors R that can measure the potential Vr are represented by the second detection circuit 373b. Output (hereinafter referred to as B output). The A output and B output become strain information.

  FIG. 6 shows a deformed state of the right crank 105R when a force (stepping force) is applied by the user. (A) is a plan view seen from the upper surface 117 of the right crank 105R, (b) is a plan view seen from the inner surface 119 of the right crank 105R, and (c) is seen from the end of the right crank 105R on the crankshaft 107 side. It is a top view. In the following description, the right crank 105R will be described, but the same applies to the left crank 105L.

  When a pedaling force is applied from the user's foot via the pedal 103, the pedaling force becomes a rotational force of the crank 105, a propulsive force Ft that is a tangential force of the rotation of the crank 105, and a normal direction of the rotation of the crank 105 And the loss power Fr. At this time, the deformation state of bending deformation x, bending deformation y, tensile deformation z, and torsional deformation rz occurs in the right crank 105R.

  As shown in FIG. 6A, the bending deformation x is a deformation in which the right crank 105R is bent so as to bend from the upper surface 117 toward the lower surface 118 or from the lower surface 118 toward the upper surface 117. Is a deformation caused by That is, distortion due to deformation generated in the rotation direction of the crank 105 (distortion generated in the rotation direction of the crank 105) is detected, and rotation direction distortion generated in the crank 105 can be detected by detecting the bending deformation x. As shown in FIG. 6B, the bending deformation y is a deformation in which the right crank 105R bends from the outer surface 120 toward the inner surface 119 or from the inner surface 119 toward the outer surface 120, and the loss force Fr. Is a deformation caused by That is, distortion caused by deformation generated from the outer surface 120 of the crank 105 to the inner surface 119 or from the inner surface 119 to the outer surface 120 (strain generated in a direction perpendicular to a plane including a circle defined by the rotational motion of the right crank 105R). Therefore, it is possible to detect the inward and outward strain generated in the crank 105 by detecting the bending deformation y.

  The tensile deformation z is a deformation that is caused by the right crank 105R being stretched or compressed in the longitudinal direction, and is caused by the loss force Fr. That is, the strain due to the deformation generated in the direction in which the crank 105 is pulled or pushed in the longitudinal direction (strain generated in the direction parallel to the longitudinal direction) is detected. The strain in the tensile direction can be detected. The torsional deformation rz is that the right crank 105R is deformed so as to be twisted, and is generated by the driving force Ft. That is, distortion due to deformation generated in the direction in which the crank 105 is twisted is detected, and distortion in the torsion direction generated in the crank 105 can be detected by detecting the torsional deformation rz. In FIG. 6, the deformation directions of the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz are indicated by arrows. However, as described above, each deformation may occur in the direction opposite to the arrow. .

  Therefore, in order to measure the propulsive force Ft, either the bending deformation x or the torsional deformation rz is measured, and in order to measure the loss force Fr, either the bending deformation y or the tensile deformation z is quantitatively detected. Good.

  Here, the measurement module strain detection circuit 365 is arranged as shown in FIG. 4 and connected to the first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, and the fourth strain gauge 369d as shown in FIG. A method for detecting (measuring) the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a is compressed and thus the resistance value is decreased, and the second strain gauge 369b is expanded and the resistance value is increased. Therefore, the output A of the first detection circuit 373a is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a is expanded and thus the resistance value is increased, and the second strain gauge 369b is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a is a negative output (the potential Vab is low and the potential Vr is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a and the second strain gauge 369b are compressed, the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a is zero (there is no potential difference between the potential Vab and the potential Vr). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a and the second strain gauge 369b are stretched, so that the resistance value of both increases. For this reason, the output A of the first detection circuit 373a is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a and the second strain gauge 369b are extended, so that the resistance value of both increases. For this reason, the output A of the first detection circuit 373a is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a and the second strain gauge 369b are compressed, so that the resistance value of both decreases. For this reason, the output A of the first detection circuit 373a is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a and the second strain gauge 369b are extended, so that the resistance value of both increases. For this reason, the output A of the first detection circuit 373a is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a and the second strain gauge 369b are extended, so that the resistance value of both increases. For this reason, the output A of the first detection circuit 373a is zero.

  As described above, only the bending deformation x is detected from the A output. That is, the first detection circuit 373a is connected to the first strain gauge 369a and the second strain gauge 369b, and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, since the third strain gauge 369c and the fourth strain gauge 369d are only bent, the resistance value does not change because they are neither compressed nor expanded in the detection direction. Therefore, the B output of the second detection circuit 373b is zero. In addition, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the third strain gauge 369c and the fourth strain gauge 369d are only bent, so that the resistance value does not change because they are neither compressed nor expanded in the detection direction. Therefore, the B output of the second detection circuit 373b is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the third strain gauge 369c is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d is expanded and the resistance value is increased. Therefore, the B output of the second detection circuit 373b is a positive output (the potential Vcd is high and the potential Vr is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the third strain gauge 369c is expanded and thus the resistance value is increased, and the fourth strain gauge 369d is compressed and the resistance value is decreased. Therefore, the output B of the second detection circuit 373b is a negative output (the potential Vcd is low and the potential Vr is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, the third strain gauge 369c is extended and the resistance value is increased, and the fourth strain gauge 369d is compressed and the resistance value is decreased. Therefore, the B output of the second detection circuit 373b is a negative output. When the right crank 105R is compressed, the third strain gauge 369c is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d is expanded and the resistance value is increased. Therefore, the B output of the second detection circuit 373b is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the resistance value increases because the third strain gauge 369c is expanded, and the resistance value does not change because the fourth strain gauge 369d does not deform in the detection direction. . Therefore, the B output of the second detection circuit 373b is a negative output. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the third strain gauge 369c is expanded, so that the resistance value increases, and the fourth strain gauge 369d is not deformed in the detection direction, so the resistance value Does not change. Therefore, the B output of the second detection circuit 373b is a negative output.

  As described above, the bending deformation y, the tensile deformation z, and the torsional deformation rz are detected from the B output. That is, the second detection circuit 373b is connected to the third strain gauge 369c and the fourth strain gauge 369d, and detects the inward / outward strain or tensile strain generated in the crank 105.

From the A output of the first detection circuit 373a and the B output of the second detection circuit 373b, the propulsive force Ft is calculated by the following equation (1), and the loss force Fr is calculated by the following equation (2). The tensile deformation z is very small compared to the bending deformation y and can be ignored.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s | A−A0 | + u (B−B0) [kgf] (2)

Here, A is the A output value at the time of calculating the propulsive force Ft (or loss force Fr), A0 is the A output value at no load, and B is B at the time of calculating the propulsive force Ft (or loss force Fr). The output value, B0 is the B output value when there is no load, p, q, s, u are coefficients, which are values calculated by simultaneous equations consisting of the following equations (3) to (6).
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  Here, Am is an A output value when m [kg] is put on the pedal 103 with the angle of the crank 105 facing forward in the horizontal direction (a state where the crank 105 is horizontal and extends in the direction of the front wheel 5). Be is the B output value when the angle of the crank 105 is horizontally forward and m [kg] is placed on the pedal 103. Ae is an A output value when m [kg] is placed on the pedal 103 with the angle of the crank 105 being vertically downward (a state in which the crank 105 extends vertically and toward the ground). Bm is the B output value when the angle of the crank 105 is vertically downward and m [kg] is placed on the pedal 103.

  Since the coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance, the propulsive force Ft can be calculated by substituting A and B into the equation (1).

  In the equation (1), the A output is corrected using the B output. In equation (2), the A output is used to correct the B output. That is, the measurement module control unit 351 that performs calculation of each formula described later functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a or the 2nd detection circuit 373b can be excluded. If the first strain gauge 369a and the second strain gauge 369b are not displaced in the crank direction (the direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary.

  Next, the block configuration of the cycle computer 201 will be described. As shown in FIG. 3, the cycle computer 201 includes a cycle computer display unit 203, a cycle computer operation unit 205, a cycle computer cadence wireless reception unit 207, a cycle computer wireless reception unit 209, a cycle computer timer 261, and a cycle computer storage unit 253. And a cycle computer control unit 251.

  The cycle computer display unit 203 displays various types of information based on user instructions and the like. In this embodiment, the propulsive force and the loss force are visualized and displayed. Any visualization method may be used. The visualization method in the cycle computer display unit 203 can be, for example, vector display, graph display, color-coded display, symbol display, three-dimensional display, and any method. Also, a combination thereof may be used.

  The cycle computer operation unit 205 receives a user instruction (input). For example, the cycle computer operation unit 205 receives a display content instruction from the user on the cycle computer display unit 203.

  The cycle computer cadence wireless reception unit 207 receives cadence information transmitted from the cadence sensor 501.

  The cycle computer wireless reception unit 209 receives the propulsive force and loss force information transmitted from the measurement module 301.

  The cycle computer timer 261 is a timer counter and counts the timer. The timer value information generated by the cycle computer timer 261 is used in various ways by the cycle computer control unit 251 and the like.

  Various information is stored in the cycle computer storage unit 253. The various information is, for example, a control program of the cycle computer control unit 251 and temporary information required when the cycle computer control unit 251 performs control. The cycle computer storage unit 253 includes a cycle computer RAM 255 and a cycle computer ROM 257. The cycle computer ROM 257 stores a control program and various parameters, constants, and the like for converting propulsive force and loss force into data that is visually displayed on the cycle computer display unit 203.

  The cycle computer control unit 251 comprehensively controls the cycle computer 201. Further, the cadence sensor 501 and the measurement module 301 may be comprehensively controlled. The cycle computer control unit 251 converts the propulsive force and the loss force into data that is visually displayed on the cycle computer display unit 203.

  Next, processing of the cadence sensor 501 and processing of the measurement module 301 and the cycle computer 201 will be described with reference to FIGS.

  First, the processing of the cadence sensor 501 will be described. In step ST51, the cadence sensor control unit 551 of the cadence sensor 501 detects a change of the magnetic sensor 505 to ON. When the cadence sensor control unit 551 detects a change in the magnetic sensor 505, the cadence sensor control unit 551 interrupts the process, and starts the processes after step ST53. Interruption means to interrupt a process so far and execute a specified process.

  Next, in step ST53, the cadence sensor control unit 551 calculates a cadence value. The cadence sensor control unit 551 calculates the time (period) [seconds] at which the magnetic sensor 505 is turned on by multiplying the count value (C) of the timer value information by one count interval (T). Then, the cadence sensor control unit 551 calculates cadence [rpm] by dividing 60 by this time (cycle). Further, the cadence sensor control unit 551 stores the cadence information in the cadence sensor RAM 555 of the cadence sensor storage unit 553.

  Next, in step ST55, the cadence sensor control unit 551 outputs a counter value reset command to the cadence sensor timer 561. Thus, the main flow of control of the cadence sensor control unit 551 is completed. Then, when the magnetic sensor 505 is turned on next time, the interruption is performed again, and the process is restarted from step ST51.

  On the other hand, in step ST57, the cadence sensor control unit 551 transmits the cadence information stored in the cadence sensor storage unit 553 to the cycle computer 201 using the cadence sensor wireless transmission unit 507. The transmission may be performed only by the cadence sensor wireless transmission unit 507 without using the cadence sensor control unit 551.

  Next, in step ST59, the cadence sensor control unit 551 waits for 1 second. The wait time is variable.

  Next, processing of the measurement module 301 and the like will be described. In step ST11, the measurement module A / D 363 A / D converts the output (A output, B output) from the measurement module strain detection circuit 365 from an analog value to a digital value. That is, this step is a rotational direction strain detection step in which the first detection circuit 373a detects rotational direction strain and an inward / outward strain in which the second detection circuit 373b detects at least one of inward / outward strain or tensile strain. Functions as a tensile strain detection process.

  Next, in step ST <b> 13, the strain information detected (converted) by the measurement module A / D 363 is stored in the measurement module RAM 355 of the measurement module storage unit 353.

  Next, in step ST15, the process waits for 1 / N seconds. Here, the value of N is the number of data points measured per second. That is, the larger the value of N, the greater the number of strain information and the higher the resolution in seconds. The larger the N value, the better. However, if the N value is increased too much, the measurement module RAM 355 must have a large capacity, resulting in an increase in cost. Therefore, the N value can be determined by the cost, the required time resolution, the time required for the measurement module A / D 363 to perform A / D conversion, and the like. When the process of step ST15 ends, the process returns to step ST11 again. That is, the processing of step ST11 to step ST15 is repeated N times per second.

  Further, the measurement module control unit 351 performs the process of FIG. In step ST31, the measurement module control unit 351 saves the strain information data. The reason will be explained. First, the capacity of the measurement module RAM 355 in the measurement module storage unit 353 is limited. Here, if the capacity of the measurement module RAM 355 is increased, it is not necessary to save the strain information data. However, designing with a sufficient margin increases the cost and is not appropriate. In addition, since strain information is continuously written one after another, if data is not saved, new information may be overwritten before the propulsive force Ft and the loss force Fr are calculated by the processing in step ST33 described later. Because there is.

  Next, in step ST33, the measurement module control unit 351 calculates the propulsive force Ft and the loss force Fr. Specifically, the measurement module control unit 351 calculates the propulsive force Ft and the loss force Fr by the above-described equations (1) and (2). Further, the measurement module control unit 351 calculates N of the propulsive force Ft and the loss force Fr and calculates the average thereof. That is, the measurement module control unit 351 calculates an average (average propulsive force and average loss force) of the propulsive force Ft and the loss force Fr for one second. That is, in this step, the driving force measurement process that measures the driving force based on the rotational direction strain detected in the rotational direction strain detection process, and the internal / external direction strain or tensile direction strain detected in the internal / external direction strain or tensile direction strain detection process. It functions as a loss force measurement process which measures a loss force based on at least one of these.

  Next, in step ST35, the measurement module control unit 351 transmits the calculated average propulsive force and average loss force via the measurement module wireless transmission unit 309. The transmitted average propulsive force and average loss force are received by the cycle computer radio reception unit 209 of the cycle computer 201.

  Next, in step ST37, one second is waited. One second is an example and can be changed as necessary. When the process of step ST37 ends, the process returns to step ST31 again. That is, the processing of step ST31 to step ST35 is repeated once per second.

  Further, the cycle computer control unit 251 of the cycle computer 201 performs the process of FIG. In step ST71, when the cycle computer control unit 251 receives the average propulsive force, average loss force, and cadence information, an interrupt is performed. That is, when the cycle computer control unit 251 detects that the cycle computer wireless reception unit 209 has received the average propulsive force, average loss force, and cadence information, the cycle computer control unit 251 interrupts the processing up to that point (interrupt). Then, the processing after step ST73 is started.

  Next, in step ST73, the cycle computer control unit 251 causes the cycle computer display unit 203 to display the average propulsive force, the average loss force, and the cadence. The cycle computer display unit 203 displays the average propulsive force, average loss force, and cadence information as numerical values, or transmits them to the user by other visualization, hearing, and tactile methods.

  Next, in step ST75, the cycle computer control unit 251 stores the average propulsive force, average loss force, and cadence information in the cycle computer RAM 255 of the cycle computer storage unit 253. Thereafter, the cycle computer control unit 251 performs other processes until the interrupt of step ST51 is performed again.

  According to this embodiment, the measurement module 301 includes a first strain gauge 369a, a second strain gauge 369b, a third strain gauge 369c, and a fourth strain gauge 369d provided on the inner surface 119 of the crank 105 of the bicycle 1. The first strain gauge 369a and the second strain gauge 369b are connected, the first detection circuit 373a for detecting the bending deformation x generated in the crank, the third strain gauge 369c and the fourth strain gauge 369d are connected, and the crank 105 is connected. A second detection circuit 373b that detects the bending deformation y and the tensile deformation z that have occurred. The first strain gauge 369 a to the third strain gauge 369 c are provided so that the detection direction is parallel to the longitudinal direction of the crank 105, and the fourth strain gauge 369 d is detected with respect to the longitudinal direction of the crank 105. It is provided so that the direction is vertical. By doing so, the propulsive force Ft and the loss force applied to the crank 105 from the bending deformation x detected by the first detection circuit 373a and the bending deformation y and the tensile deformation z detected by the second detection circuit 373b. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, since the first strain gauge 369a to the fourth strain gauge 369d are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface 119 By providing in, it does not interfere with the user's foot.

  Further, since the first strain gauge 369a and the second strain gauge 369b are provided so as to be symmetric with respect to the central axis C1 in the longitudinal direction of the inner surface 119 of the crank 105, the bending deformation x can be detected with high accuracy. it can.

  In addition, the first detection circuit 373a and the second detection circuit 373b are configured as a bridge circuit, and the first strain gauge 369a and the second strain gauge 369b are serially connected to the power supply in the bridge circuit configuring the first detection circuit 373a. The third strain gauge 369c and the fourth strain gauge 369d are connected in series to the power source in the bridge circuit that constitutes the second detection circuit 373b, and further, the bridge circuit that constitutes the first detection circuit 373a and the first Since the resistance elements other than the first strain gauge 369a to the fourth strain gauge 369d of the bridge circuit constituting the 2 detection circuit 373b are configured by the fixed resistance R, the bridge circuit causes the bending deformation x, the bending deformation y, and the tension. Deformation z can be detected and propulsive force Ft and loss force with a simple circuit configuration It is possible to measure the r.

  Further, since the fixed resistor R is shared by the first detection circuit and the second detection circuit, the first detection circuit and the second detection circuit can be practically made into one circuit, and the circuit is further simplified. Can be.

  Further, since the torsional deformation rz does not act on the calculation of the propulsive force Ft, the propulsive force Ft does not change even if the load position on the pedal 103 changes.

  In the above description, the third strain gauge 369c and the fourth strain gauge 369d are provided as separate elements. However, they may be stacked in a cross shape, for example. By doing so, the size of the strain gauge 369 provided in the crank 105 can be reduced. Further, when the third strain gauge 369c and the fourth strain gauge 369d are provided as separate elements, the fourth strain gauge 369d is not limited to being provided closer to the pedal crankshaft 115 than the third strain gauge 369c. 369d may be provided closer to the crankshaft 107 than the third strain gauge 369c. That is, the arrangement order of the third strain gauge 369c and the fourth strain gauge 369d is not particularly limited.

  In FIG. 5, the two bridge circuits are combined into one circuit, but may be divided into two bridge circuits as separate circuits. In that case, two fixed resistors R are required for each circuit.

  In the first detection circuit 373a, the connection order of the first strain gauge 369a and the second strain gauge 369b may be reversed. In the second detection circuit 373b, the connection order of the third strain gauge 369c and the fourth strain gauge 369d may be reversed.

  Next, a measuring apparatus according to a second embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 9, the strain gauge 369 of the present embodiment includes a first strain gauge 369a, a second strain gauge 369b, a third strain gauge 369c, a fourth strain gauge 369d, a fifth strain gauge 369e, and a sixth strain gauge. 369f, a seventh strain gauge 369g, and an eighth strain gauge 369h. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 10 shows an arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The first strain gauge 369a and the second strain gauge 369b are the same as those in the first embodiment shown in FIG.

  The third strain gauge 369c is provided on the central axis C1, and the detection direction is provided in parallel to the central axis C1. The fourth strain gauge 369d is provided with a detection direction perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C1 of the inner surface 119.

  The fifth strain gauge 369e, the sixth strain gauge 369f, and the seventh strain gauge 369g are provided so that the detection direction is perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C1 of the inner surface 119. The eighth strain gauge 369h is provided on the central axis C1, and the detection direction is provided in parallel to the central axis C1.

  The third strain gauge 369c and the eighth strain gauge 369h are arranged side by side along the central axis C1. The fourth strain gauge 369d and the seventh strain gauge 369g are arranged so as to sandwich the third strain gauge 369c. The fifth strain gauge 369e and the sixth strain gauge 369f are arranged so as to sandwich the eighth strain gauge 369h. Further, the first strain gauge 369a and the second strain gauge 369b are disposed closer to both ends in the short direction of the crank 105 than the third strain gauge 369c to the eighth strain gauge 369h.

  That is, the direction parallel to the central axis C1 (the vertical direction in FIG. 10), that is, the direction parallel to the longitudinal direction of the crank 105 is the first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, The fourth strain gauge 369d and the fifth strain gauge are the detection directions of the eighth strain gauge 369h, and the direction perpendicular to the central axis C1 (the lateral direction in FIG. 10), that is, the direction perpendicular to the longitudinal direction of the crank. 369e, the sixth strain gauge 369f, and the seventh strain gauge 369g are detected directions. Accordingly, the first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, the eighth strain gauge 369h, the fourth strain gauge 369d, the fifth strain gauge 369e, the sixth strain gauge 369f, and the seventh strain gauge 369g. Are orthogonal to each other.

  The measurement module strain detection circuit 365 of the present embodiment includes the first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, the fourth strain gauge 369d, the fifth strain gauge 369e, the sixth strain gauge 369f, The seventh strain gauge 369g and the eighth strain gauge 369h are connected, and the strain amount of the strain gauge 369 is output as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information which is digital information by the measurement module A / D 363 as in the first embodiment. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373c and a second detection circuit 373d that are two bridge circuits. On the first system side of the first detection circuit 373c, the first strain gauge 369a and the second strain gauge 369b are connected in this order from the power source Vcc. That is, the first strain gauge 369a and the second strain gauge 369b are connected in series with the power supply Vcc. On the second system side, the fifth strain gauge 369e and the sixth strain gauge 369f are connected in this order. That is, the fifth strain gauge 369e and the sixth strain gauge 369f are connected in series to the power supply Vcc.

  In the first detection circuit 373c, the first strain gauge 373a and the sixth strain gauge 373f are connected to diagonal positions, and the second strain gauge 373b and the fifth strain gauge 373e are connected to diagonal positions. .

  On the first system side of the second detection circuit 373d, the third strain gauge 369c and the fourth strain gauge 369d are connected in this order from the power source Vcc. That is, the third strain gauge 369c and the fourth strain gauge 369d are connected in series with the power supply Vcc. On the second system side, the seventh strain gauge 369g and the eighth strain gauge 369h are connected in this order from the power source Vcc. That is, the seventh strain gauge 369g and the eighth strain gauge 369h are connected in series to the power source Vcc.

  In the second detection circuit 373d, the third strain gauge 373c and the eighth strain gauge 373h are connected to diagonal positions, and the fourth strain gauge 373d and the seventh strain gauge 373g are connected to diagonal positions. . The first strain gauge 369a to the eighth strain gauge 369h have the same resistance value.

  A connection point of the first strain gauge 369a and the second strain gauge 369b that can measure the potential Vab between the first strain gauge 369a and the second strain gauge 369b of the first detection circuit 373c, a fifth strain gauge 369e, The connection point between the fifth strain gauge 369e and the sixth strain gauge 369f that can measure the potential Vef between the sixth strain gauge 369f and the output of the first detection circuit 373c (hereinafter referred to as A output).

  A connection point between the third strain gauge 369c and the fourth strain gauge 369d that can measure the potential Vcd between the third strain gauge 369c and the fourth strain gauge 369d of the second detection circuit 373d, a seventh strain gauge 369g, The connection point between the seventh strain gauge 369g and the eighth strain gauge 369h that can measure the potential Vgh between the eight strain gauges 369h is defined as the output (hereinafter referred to as B output) of the second detection circuit 373d. The A output and the B output become strain information as in the first embodiment.

  Here, the measurement module strain detection circuit 365 of the present embodiment shown in FIGS. 10 and 11 detects (measures) the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz described with reference to FIG. ) Is explained.

  In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a is compressed and thus the resistance value is decreased, and the second strain gauge 369b is expanded and the resistance value is increased. On the other hand, since the fifth strain gauge 369e is expanded, the resistance value increases, and since the sixth strain gauge 369f is compressed, the resistance value decreases. Therefore, the output A of the first detection circuit 373c is a positive output (the potential Vab is high and the potential Vef is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a is expanded and thus the resistance value is increased, and the second strain gauge 369b is compressed and the resistance value is decreased. On the other hand, since the fifth strain gauge 369e is compressed, the resistance value decreases, and the sixth strain gauge 369f is expanded, so the resistance value increases. Therefore, the output A of the first detection circuit 373c is a negative output (the potential Vab is low and the potential Vcd is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a and the second strain gauge 369b are compressed, the resistance value of both decreases. On the other hand, since both the fifth strain gauge 369e and the sixth strain gauge 369f are expanded, both increase in resistance value. Therefore, the output A of the first detection circuit 373c is zero (there is no potential difference between the potential Vab and the potential Vcd). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a and the second strain gauge 369b are stretched, so that the resistance value of both increases. On the other hand, since both the fifth strain gauge 369e and the sixth strain gauge 369f are compressed, the resistance value of both decreases. For this reason, the output A of the first detection circuit 373c is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a and the second strain gauge 369b are extended, so that the resistance value of both increases. On the other hand, since both the fifth strain gauge 369e and the sixth strain gauge 369f are compressed, the resistance value of both decreases. For this reason, the output A of the first detection circuit 373c is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a and the second strain gauge 369b are compressed, so that the resistance value of both decreases. On the other hand, since both the fifth strain gauge 369e and the sixth strain gauge 369f are expanded, both increase in resistance value. For this reason, the output A of the first detection circuit 373c is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted as shown in FIG. 6B, both the first strain gauge 369a and the second strain gauge 369b are stretched, so that the resistance value of both increases. On the other hand, since neither the fifth strain gauge 369e nor the sixth strain gauge 369f is compressed or expanded in the detection direction, the resistance value does not change. For this reason, the output A of the first detection circuit 373c is zero. Further, when the right crank 105R is twisted in the reverse direction of FIG. 6B, both the first strain gauge 369a and the second strain gauge 369b are expanded, so that the resistance value of both increases. On the other hand, since neither the fifth strain gauge 369e nor the sixth strain gauge 369f is compressed or expanded in the detection direction, the resistance value does not change. For this reason, the output A of the first detection circuit 373c is zero.

  As described above, only the bending deformation x is detected from the output A as in the first embodiment. That is, the first detection circuit 373c is connected to the first strain gauge 369a, the second strain gauge 369b, the fifth strain gauge 373e, and the sixth strain gauge 373f, and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373d will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the third strain gauge 369c only bends and is not compressed or expanded in the detection direction, so the resistance value does not change, and the fourth strain gauge 369d is compressed. As a result, the resistance value decreases. On the other hand, since the seventh strain gauge 369g is expanded, the resistance value increases, and the eighth strain gauge 369h only bends, so that the resistance value does not change because it is neither compressed nor expanded in the detection direction. For this reason, the B output of the second detection circuit 373d is zero. Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the third strain gauge 369c only bends, and therefore, the resistance value does not change because the third strain gauge 369c is not compressed or expanded in the detection direction. The resistance value increases because the is stretched. On the other hand, since the seventh strain gauge 369g is compressed, the resistance value decreases, and the eighth strain gauge 369h only bends. Therefore, the resistance value does not change because it is neither compressed nor expanded in the detection direction. For this reason, the B output of the second detection circuit 373d is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the third strain gauge 369c is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d is expanded and the resistance value is increased. On the other hand, since the seventh strain gauge 369g is expanded, the resistance value increases, and since the eighth strain gauge 369h is compressed, the resistance value decreases. Therefore, the output B of the second detection circuit 373d is a positive output (the potential Vcd is high and the potential Vgh is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the third strain gauge 369c is expanded and thus the resistance value is increased, and the fourth strain gauge 369d is compressed and the resistance value is decreased. On the other hand, since the seventh strain gauge 369g is compressed, the resistance value decreases, and the eighth strain gauge 369h is expanded, so the resistance value increases. For this reason, the B output of the second detection circuit 373d is a negative output (the potential Vcd is low and the potential Vgh is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. Since the third strain gauge 369c is expanded, the resistance value increases, and since the fourth strain gauge 369d is compressed, the resistance value decreases. On the other hand, since the seventh strain gauge 369g is compressed, the resistance value decreases, and the eighth strain gauge 369h is expanded, so the resistance value increases. Therefore, the B output of the second detection circuit 373d is a negative output. When the right crank 105R is compressed, the third strain gauge 369c is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d is expanded and the resistance value is increased. On the other hand, since the seventh strain gauge 369g is expanded, the resistance value increases, and since the eighth strain gauge 369h is compressed, the resistance value decreases. Therefore, the B output of the second detection circuit 373d is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted as shown in FIG. 6B, the third strain gauge 369c is expanded and thus the resistance value is increased, and the fourth strain gauge 369d is compressed and the resistance value is decreased. On the other hand, since the seventh strain gauge 369g is compressed, the resistance value decreases, and the eighth strain gauge 369h is expanded, so the resistance value increases. Therefore, the B output of the second detection circuit 373d is a negative output. Further, when the right crank 105R is twisted in the reverse direction of FIG. 6B, the third strain gauge 369c is expanded and thus the resistance value is increased, and the fourth strain gauge 369d is compressed and the resistance value is decreased. On the other hand, since the seventh strain gauge 369g is compressed, the resistance value decreases, and the eighth strain gauge 369h is expanded, so the resistance value increases. Therefore, the B output of the second detection circuit 373d is a negative output.

  As described above, the bending deformation y, the tensile deformation z, and the torsional deformation rz are detected from the B output. In other words, the second detection circuit 373d is connected to the third strain gauge 369c, the fourth strain gauge 369d, the seventh strain gauge 369g, and the eighth strain gauge 369h. Is detected.

  The propulsive force Ft and the loss force Fr are calculated by the above-described equations (1) to (6) as in the first embodiment.

  There is no deviation in the crank direction (direction parallel to the central axis C1) between the first strain gauge 369a and the second strain gauge 369b and between the fifth strain gauge 369e and the sixth strain gauge 369f. In this case, Ae = A0 and correction by the B output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to this embodiment, the measurement module 301 includes a first strain gauge 369a, a second strain gauge 369b, a third strain gauge 369c, a fourth strain gauge 369d, and a fifth strain gauge provided on the inner surface 119 of the crank 105 of the bicycle 1. A strain gauge 369e, a sixth strain gauge 369f, a seventh strain gauge 369g, an eighth strain gauge 369h, a first strain gauge 369a, a second strain gauge 369b, a fifth strain gauge 369e, and a sixth strain gauge 369f are connected. A first detection circuit 373c that detects a bending deformation x generated in the crank 105 is connected to a third strain gauge 369c, a fourth strain gauge 369d, a seventh strain gauge 369g, and an eighth strain gauge 369h, and is generated in the crank 105. Second test to detect bending deformation y and tensile deformation z It has a circuit 373 d, a. The first strain gauge 369a, the second strain gauge 369b, the third strain gauge 369c, and the eighth strain gauge 369h are provided so that the detection direction is parallel to the longitudinal direction of the crank 105, and the fourth strain gauge 369d, a fifth strain gauge 369e, a sixth strain gauge 369f, and a seventh strain gauge 369g are provided so that the detection direction is perpendicular to the longitudinal direction of the crank 105. By doing so, the propulsive force Ft and the loss force applied to the crank 105 from the bending deformation x detected by the first detection circuit 373c and the bending deformation y and the tensile deformation z detected by the second detection circuit 373d. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, since the first strain gauge 369a to the eighth strain gauge 369h are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface By providing at 119, there is no interference with the feet of the driver. Further, since the first strain gauge 369a, the second strain gauge 369b, the fifth strain gauge 369e, and the sixth strain gauge 369f are connected to the first detection circuit 373c to detect the bending deformation x, the detected voltage value Becomes larger and the influence of noise can be reduced.

  In addition, the first detection circuit 373c and the second detection circuit are configured by a bridge circuit, and the first strain gauge 369a, the sixth strain gauge 369f, the second strain gauge 369b, and the fifth strain gauge 369e constitute the first detection circuit 373c. Bridges that are respectively connected to diagonal positions in the bridge circuit that is configured, and the third strain gauge 369c and the eighth strain gauge 369h, the fourth strain gauge 369d, and the seventh strain gauge 369g constitute the second detection circuit 373d. Each may be connected to a diagonal position in the circuit. By doing so, the bending deformation x, the bending deformation y, and the tensile deformation z can be detected by the bridge circuit, and the propulsive force and the loss force can be measured with a simple circuit configuration.

  In the second embodiment, the position of the strain gauge 369 of the bridge circuit can be changed. For example, in the first detection circuit 373c, the first strain gauge 369a and the second strain gauge 369b may be interchanged. In this case, it is necessary to replace the fifth strain gauge 369e and the sixth strain gauge 369f in order to maintain the diagonal positional relationship. The position of the second detection circuit 373d can be changed in the same manner.

  Also in the second embodiment, a plurality of strain gauges 369 can be stacked. For example, the third strain gauge 369c and the fourth strain gauge 369d or the seventh strain gauge 369g may be stacked in a cross shape. The eighth strain gauge 369h and the fifth strain gauge 369e or the sixth strain gauge 369f may be stacked in a cross shape.

  Next, a measuring apparatus according to a third embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 12, the strain gauge 369 of the present embodiment includes a first strain gauge 369a3, a second strain gauge 369b3, a third strain gauge 369c3, a fourth strain gauge 369d3, a fifth strain gauge 369e3, and a sixth strain gauge. 369f3. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 13 shows an arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119, the upper surface 117, and the lower surface 118 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. The upper surface 117 of the crank 105 extends in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 (extends in the radial direction of a circle defined by the rotational motion of the crank 105), and is one of the surfaces orthogonal to the inner surface 119. It is. A lower surface 118 of the crank 105 is a surface facing the upper surface 117. Although not illustrated in FIG. 13, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided.

  As shown in FIG. 13B, the first strain gauge 369a3 and the second strain gauge 369b3 are provided on the inner surface 119 of the crank 105. The first strain gauge 369a3 and the second strain gauge 369b3 have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119 and to the central axis C1 of the inner surface 119. It is provided to be symmetrical.

  The third strain gauge 369c3 and the fourth strain gauge 369d3 are provided on the upper surface 117 of the crank 105 as shown in FIG. The third strain gauge 369d3 is provided on the central axis C2 with the detection direction perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C2 of the upper surface 117. The fourth strain gauge 369d3 is provided on the central axis C2 so that the detection direction is parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C2 of the upper surface 117.

  The fifth strain gauge 369e3 and the sixth strain gauge 369f3 are provided on the lower surface 118 of the crank 105 as shown in FIG. The fifth strain gauge 369e3 is provided on the central axis C3 with a detection direction perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C3 of the lower surface 118. The sixth strain gauge 369f3 is provided on the central axis C3 so that the detection direction is parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C3 of the lower surface 118.

  That is, a direction parallel to the central axes C1, C2, and C3 (vertical direction in FIG. 13) that is an axis extending in the longitudinal direction of the crank 105, that is, a direction parallel to the longitudinal direction of the crank 105 is the first strain gauge. 369a3, the second strain gauge 369b3, the fourth strain gauge 369d3, and the sixth strain gauge 369f3, and the direction perpendicular to the central axes C2, C3 (lateral direction in FIG. 13), that is, the longitudinal direction of the crank 105 This direction is the detection direction of the third strain gauge 369c3 and the fifth strain gauge 369e3. Therefore, the detection directions of the first strain gauge 369a3, the second strain gauge 369b3, the fourth strain gauge 369d3, the sixth strain gauge 369f3, the third strain gauge 369c3, and the fifth strain gauge 369e3 are orthogonal to each other.

  The arrangement of the first strain gauges 369a3 to the sixth strain gauges 369f3 is not limited to FIG. That is, other arrangements may be used as long as the parallel or perpendicular relationship with the central axes C1, C2, and C3 is maintained. However, the first strain gauge 369a3 and the second strain gauge 369b3 are arranged symmetrically with respect to the central axis C1, and the third strain gauge 369c3 to the sixth strain gauge 369f3 are arranged on the central axes C2 and C3. It is preferable because each deformation described later can be detected with high accuracy.

  In FIG. 13, the crank 105 is described as a simple rectangular parallelepiped, but the corners may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel or vertical) with the central axes C1, C2, and C3 deviates.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a3, the second strain gauge 369b3, the third strain gauge 369c3, the fourth strain gauge 369d3, the fifth strain gauge 369e3, and the sixth strain gauge 369f3. A strain amount of 369 is output as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a3 and a second detection circuit 373b3 that are two bridge circuits. On the first system side of the first detection circuit 373a3, the first strain gauge 369a3 and the second strain gauge 369b3 are connected in this order from the power source Vcc. That is, the first strain gauge 369a3 and the second strain gauge 369b3 are connected in series to the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc.

  On the first system side of the second detection circuit 373b3, the fourth strain gauge 369d3 and the third strain gauge 369c3 are connected in this order from the power source Vcc. That is, the third strain gauge 369c3 and the fourth strain gauge 369d3 are connected in series with the power supply Vcc. On the second system side, the fifth strain gauge 369e3 and the sixth strain gauge 369f3 are connected in this order from the power source Vcc. That is, the fifth strain gauge 369e3 and the sixth strain gauge 369f3 are connected in series to the power supply Vcc.

  In the second detection circuit 373b3, the third strain gauge 373c3 and the fifth strain gauge 373e3 are connected to diagonal positions, and the fourth strain gauge 373d3 and the sixth strain gauge 373f3 are connected to diagonal positions. . The first strain gauge 369a3 to the sixth strain gauge 369f3 have the same resistance value. The two fixed resistors R have the same resistance value as that before the compression or expansion of the strain gauge 369 occurs.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a3, the second strain gauge 369b3, the fourth strain gauge 369d3, and the sixth strain gauge 369f3 are center axes. The direction parallel to C1, C2, and C3, the third strain gauge 369c3, and the fifth strain gauge 369e3 are perpendicular to the central axes C2 and C3. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first strain gauge 369a3 and the second strain gauge 369b3 are not compressed or expanded in the detection direction, the first detection circuit 373a3 using the strain gauge 369 having such characteristics has the first strain gauge 369a3 and the first strain gauge 369a3. The potential difference between the potential Vab between the two strain gauges 369b3 and the potential Vr between the two fixed resistors R is almost zero.

  When the first strain gauge 369a3 is compressed and the second strain gauge 369b3 is expanded, the resistance value of the first strain gauge 369a3 decreases and the resistance value of the second strain gauge 369b3 increases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a3 is expanded and the second strain gauge 369b3 is compressed, the resistance value of the first strain gauge 369a3 increases and the resistance value of the second strain gauge 369b3 decreases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a3 and the second strain gauge 369b3 are compressed, the resistance value of both the first strain gauge 369a3 and the second strain gauge 369b3 decreases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a3 and the second strain gauge 369b3 are extended, the resistance value of both the first strain gauge 369a3 and the second strain gauge 369b3 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  When the third strain gauge 369c3 to the sixth strain gauge 369f3 are not compressed or expanded in the detection direction, the second detection circuit 373b3 has a potential Vcd between the third strain gauge 369c3 and the fourth strain gauge 369d3, The potential difference between the fifth strain gauge 369e3 and the sixth strain gauge 369f3 and the potential Vef is almost zero.

  When the fourth strain gauge 369d3 is compressed and the third strain gauge 369c3 is expanded, the resistance value of the fourth strain gauge 369d3 decreases and the resistance value of the third strain gauge 369c3 increases. Get higher. At this time, when the fifth strain gauge 369e3 is compressed and the sixth strain gauge 369f3 is expanded, the resistance value of the fifth strain gauge 369e3 decreases and the resistance value of the sixth strain gauge 369f3 increases. The potential Vef becomes higher, and the potential difference between the potential Vcd and the potential Vef becomes almost zero. On the other hand, when the fifth strain gauge 369e3 is expanded and the sixth strain gauge 369f3 is compressed, the resistance value of the fifth strain gauge 369e3 increases and the resistance value of the sixth strain gauge 369f3 decreases. Vef is lowered, and a potential difference is generated between the potential Vcd and the potential Vef. Furthermore, since the potential Vef does not change when the fifth strain gauge 369e3 and the sixth strain gauge 369f3 are not compressed or expanded, a potential difference is generated between the potential Vcd and the potential Vef.

  When the fourth strain gauge 369d3 is expanded and the third strain gauge 369c3 is compressed, the resistance value of the fourth strain gauge 369d3 increases and the resistance value of the third strain gauge 369c3 decreases. Lower. At this time, when the fifth strain gauge 369e3 is compressed and the sixth strain gauge 369f3 is expanded, the resistance value of the fifth strain gauge 369e3 decreases and the resistance value of the sixth strain gauge 369f3 increases. The potential Vef increases, and a potential difference is generated between the potential Vcd and the potential Vef. On the other hand, when the fifth strain gauge 369e3 is expanded and the sixth strain gauge 369f3 is compressed, the resistance value of the fifth strain gauge 369e3 increases and the resistance value of the sixth strain gauge 369f3 decreases. Vef becomes low, and the potential difference between the potential Vcd and the potential Vef becomes almost zero. Furthermore, since the potential Vef does not change when the fifth strain gauge 369e3 and the sixth strain gauge 369f3 are not compressed or expanded, a potential difference is generated between the potential Vcd and the potential Vef.

  When the fourth strain gauge 369d3 and the third strain gauge 369c3 are not compressed or expanded, the resistance value of the fourth strain gauge 369d3 and the third strain gauge 369c3 does not change, so the potential Vcd does not change. At this time, when the fifth strain gauge 369e3 is compressed and the sixth strain gauge 369f3 is expanded, the resistance value of the fifth strain gauge 369e3 decreases and the resistance value of the sixth strain gauge 369f3 increases. The potential Vef increases, and a potential difference is generated between the potential Vcd and the potential Vef. On the other hand, when the fifth strain gauge 369e3 is expanded and the sixth strain gauge 369f3 is compressed, the resistance value of the fifth strain gauge 369e3 increases and the resistance value of the sixth strain gauge 369f3 decreases. Vef is lowered, and a potential difference is generated between the potential Vcd and the potential Vef.

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a3 and the second strain gauge 369b3 capable of measuring the potential Vab of the first detection circuit 373a3 and a connection point between the two fixed resistors R capable of measuring the potential Vr. The output of 373a3 (hereinafter referred to as A output). A connection point between the third strain gauge 369c3 and the fourth strain gauge 369d3 capable of measuring the potential Vcd of the second detection circuit 373b3; a connection point between the fifth strain gauge 369e3 and the sixth strain gauge 369f3 capable of measuring the potential Vef; Is the output of the second detection circuit 373b3 (hereinafter referred to as B output). The A output and B output become strain information.

  Here, the first strain gauge 369a3, the second strain gauge 369b3, the third strain gauge 369c3, the fourth strain gauge 369d3, the fifth strain gauge 369e3, and the sixth strain gauge are arranged as shown in FIG. A method of detecting (measuring) the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz by the measurement module strain detection circuit 365 to which 369f3 is connected will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a3 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a3 is compressed and thus the resistance value decreases, and the second strain gauge 369b3 is expanded and the resistance value increases. Therefore, the output A of the first detection circuit 373a3 is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a3 is expanded and thus the resistance value is increased, and the second strain gauge 369b3 is compressed and the resistance value is decreased. For this reason, the output A of the first detection circuit 373a3 is a negative output (the potential Vab is low and the potential Vr is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a3 and the second strain gauge 369b3 are compressed, the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a3 is zero (there is no potential difference between the potential Vab and the potential Vr). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a3 and the second strain gauge 369b3 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a3 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a3 and the second strain gauge 369b3 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a3 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a3 and the second strain gauge 369b3 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a3 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a3 and the second strain gauge 369b3 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a3 is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a3 and the second strain gauge 369b3 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a3 is zero.

  As described above, only the bending deformation x is detected from the A output. That is, the first detection circuit 373a3 is connected to the first strain gauge 369a3 and the second strain gauge 369b3, and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b3 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the third strain gauge 369c3 is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d3 is expanded and the resistance value is increased. On the other hand, since the fifth strain gauge 369e3 is expanded, the resistance value increases, and since the sixth strain gauge 369f3 is compressed, the resistance value decreases. Therefore, the B output of the second detection circuit 373b3 becomes zero. Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the third strain gauge 369c3 is expanded, so that the resistance value is increased, and the fourth strain gauge 369d3 is compressed, so that the resistance value is decreased. On the other hand, since the fifth strain gauge 369e3 is compressed, the resistance value decreases, and the sixth strain gauge 369f3 is expanded, so the resistance value increases. Therefore, the B output of the second detection circuit 373b3 becomes zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the third strain gauge 369c3 to the sixth strain gauge 369f3 do not compress or expand in the detection direction, so the resistance value does not change. Therefore, the B output of the second detection circuit 373b3 is zero. When the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the third strain gauge 369c3 to the sixth strain gauge 369f3 do not compress or expand in the detection direction, so that the resistance value does not change. Therefore, the B output of the second detection circuit 373b3 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R expands, the third strain gauge 369c3 is compressed and thus the resistance value decreases, and the fourth strain gauge 369d3 is expanded and the resistance value increases. On the other hand, since the fifth strain gauge 369e3 is compressed, the resistance value decreases, and the sixth strain gauge 369f3 is expanded, so the resistance value increases. Therefore, the output B of the second detection circuit 373b3 is a positive output (the potential Vef is high and the potential Vcd is low). Further, when the right crank 105R is compressed, the third strain gauge 369c3 is expanded and thus the resistance value is increased, and the fourth strain gauge 369d3 is compressed and the resistance value is decreased. On the other hand, since the fifth strain gauge 369e3 is expanded, the resistance value increases, and since the sixth strain gauge 369f3 is compressed, the resistance value decreases. Therefore, the output B of the second detection circuit 373b3 is a negative output (the potential Vef is low and the potential Vcd is high).

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the resistance value does not change because the third strain gauge 369c3 is neither compressed nor expanded in the detection direction, and the fourth strain gauge 369d3 is expanded, so that resistance The value increases. On the other hand, since the fifth strain gauge 369e3 is neither compressed nor expanded in the detection direction, the resistance value does not change, and the sixth strain gauge 369f3 is expanded, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b3 is a positive output. When the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the third strain gauge 369c3 is neither compressed nor expanded in the detection direction, so the resistance value does not change, and the fourth strain gauge 369d3 is expanded. Therefore, the resistance value increases. On the other hand, since the fifth strain gauge 369e3 is neither compressed nor expanded in the detection direction, the resistance value does not change, and the sixth strain gauge 369f3 is expanded, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b3 is a positive output.

  As described above, the tensile deformation z and the torsional deformation rz are detected from the B output. That is, the second detection circuit 373b3 is connected to the third strain gauge 369c3 to the sixth strain gauge 369f3 and detects the strain in the tensile direction generated in the crank 105.

From the A output of the first detection circuit 373a3 and the B output of the second detection circuit 373b3, the propulsive force Ft is expressed by the equation (1) shown in the first embodiment, and the loss force Fr is expressed by the following equation (7). Respectively. The formula (1) is shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = −s | A−A0 | + u (B−B0) [kgf] (7)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  Since the coefficients p, q, s, u and A0, B0 are values that can be calculated or measured in advance, the propulsive force Ft and the loss force Fr can be obtained by substituting A and B into the equations (1) and (7). It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (7), the A output is used to correct the B output. That is, the measurement module control unit 351 that performs calculation of each formula described later functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a3 or the 2nd detection circuit 373b3 can be excluded. If the first strain gauge 369a3 and the second strain gauge 369b3 are not displaced in the crank direction (direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to this embodiment, the measurement module 301 includes a first strain gauge 369a3 and a second strain gauge 369b3 provided on the inner surface 119 of the crank 105 of the bicycle 1, and a third strain gauge provided on the upper surface 117 of the crank 105. 369c3, the fourth strain gauge 369d3, the fifth strain gauge 369e3, the sixth strain gauge 369f3 provided on the lower surface 118 of the crank 105, the first strain gauge 369a3, and the second strain gauge 369b3 are connected to be generated in the crank 105. A first detection circuit 373a3 that detects the bending deformation x, and a second detection circuit 373b3 that is connected to the third strain gauge 369c3 to the sixth strain gauge 369f3 and detects the tensile deformation z generated in the crank 105. Have. The first strain gauge 369a3, the second strain gauge 369b3, the fourth strain gauge 369d3, and the sixth strain gauge 369f3 are provided so that the detection direction is parallel to the longitudinal direction of the crank 105, and the third strain gauge 369c3 and the fifth strain gauge 369e3 are provided so that the detection direction is perpendicular to the longitudinal direction of the crank 105. Thus, the propulsive force Ft and the loss force Fr applied to the crank 105 are measured from the bending deformation x detected by the first detection circuit 373a3 and the tensile deformation z detected by the second detection circuit 373b3. be able to. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, by providing the first strain gauge 369a3 and the second strain gauge 369b3 on the inner surface 119 of the crank 105, there is no interference with the user's foot.

  Further, since the first strain gauge 369a3 and the second strain gauge 369b3 are provided so as to be symmetric with respect to the central axis C1 in the longitudinal direction of the inner surface 119 of the crank 105, the bending deformation x can be detected with high accuracy. it can.

  Further, the first detection circuit 373a3 and the second detection circuit 373b3 are configured by a bridge circuit, and the first strain gauge 369a3 and the second strain gauge 369b3 are serially connected to the power supply in the bridge circuit that configures the first detection circuit 373a3. The third strain gauge 369c3 and the fifth strain gauge 369e3, the fourth strain gauge 369d3 and the sixth strain gauge 369f3 are respectively connected to diagonal positions in the bridge circuit constituting the second detection circuit 373b3; Since the resistance elements other than the first strain gauge 369a3 and the second strain gauge 369b3 of the bridge circuit that constitutes the first detection circuit 373a3 are configured by the fixed resistance R, the bridge circuit generates the bending deformation x and the tensile deformation z. Simple circuit configuration that can be detected It is possible to measure the driving force Ft and loss force Fr.

  Further, since the torsional deformation rz does not act on the calculation of the propulsive force Ft, the propulsive force Ft does not change even if the load position on the pedal 103 changes.

  In the above description, the third strain gauge 369c3 and the fourth strain gauge 369d3 are provided as separate elements. However, they may be stacked in a cross shape, for example. Further, although the fifth strain gauge 369e3 and the sixth strain gauge 369f3 are provided as separate elements, they may be stacked on each other in a cross shape, for example. By doing so, the size of the strain gauge 369 provided in the crank 105 can be reduced. Further, the arrangement order of the third strain gauge 369c3 and the fourth strain gauge 369d3 and the arrangement order of the fifth strain gauge 369e3 and the sixth strain gauge 369f3 may be opposite to those in FIG. 13, and are not particularly limited.

  In the first detection circuit 373a3, the connection order of the first strain gauge 369a3 and the second strain gauge 369b3 may be reversed. In the second detection circuit 373b3, the connection order of the third strain gauge 369c3 and the fourth strain gauge 369d3 may be reversed. In this case, the connection order of the fifth strain gauge 369e3 and the sixth strain gauge 369f3 is also used. It needs to be replaced. That is, in the second detection circuit 373b3, the diagonal positional relationship must be maintained.

  Next, a measuring apparatus according to a fourth embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 15, the strain gauge 369 of this embodiment includes a first strain gauge 369a4, a second strain gauge 369b4, a third strain gauge 369c4, and a fourth strain gauge 369d4. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 16 shows an arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 and the upper surface 117 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 protrudes (is connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. The upper surface 117 of the crank 105 extends in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 (extends in the radial direction of a circle defined by the rotational motion of the crank 105), and is one of the surfaces orthogonal to the inner surface 119. It is. Although not shown in FIG. 16, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a and the second strain gauge 369b are provided on the inner surface 119 of the crank 105 as shown in FIG. The first strain gauge 369a and the second strain gauge 369b have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119 and to the central axis C1 of the inner surface 119. It is provided to be symmetrical.

  The third strain gauge 369c and the fourth strain gauge 369d are provided on the upper surface 117 of the crank 105 as shown in FIG. The third strain gauge 369c and the fourth strain gauge 369d have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C2 of the upper surface 117 and to the central axis C2 of the upper surface 117. It is provided to be symmetrical.

  That is, the first strain gauges 369a4 to 369a4 are parallel to the central axes C1 and C2, which are axes extending in the longitudinal direction of the crank 105 (the longitudinal direction in FIG. 16), that is, in the direction parallel to the longitudinal direction of the crank 105. This is the detection direction of the fourth strain gauge 369d4.

  Note that the arrangement of the first strain gauge 369a4 to the fourth strain gauge 369d4 is not limited to FIG. That is, other arrangements may be used as long as the parallel relationship with the central axes C1 and C2 is maintained. However, the first strain gauge 369a4 and the second strain gauge 369b4 are arranged symmetrically across the central axis C1, and the third strain gauge 369c4 and the fourth strain gauge 369d4 are arranged symmetrically across the central axis C2. However, it is preferable because each deformation described later can be detected with high accuracy.

  In FIG. 16, the crank 105 is described as a simple rectangular parallelepiped, but the corner may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel) with the center axes C1 and C2 described above shifts.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a4, the second strain gauge 369b4, the third strain gauge 369c4, and the fourth strain gauge 369d4, and the strain amount of the strain gauge 369 is output as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a4 and a second detection circuit 373b4 that are two bridge circuits. On the first system side of the first detection circuit 373a4, the first strain gauge 369a4 and the second strain gauge 369b4 are connected in this order from the power supply Vcc. That is, the first strain gauge 369a4 and the second strain gauge 369b4 are connected in series to the power source Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc. On the first system side of the second detection circuit 373b4, the third strain gauge 369c4 and the fourth strain gauge 369d4 are connected in this order from the power source Vcc. That is, the third strain gauge 369c4 and the fourth strain gauge 369d4 are connected in series to the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc.

  That is, the two fixed resistors R are shared by the first detection circuit 373a4 and the second detection circuit 373b4. Here, the two fixed resistors R have the same resistance value. The two fixed resistors R have the same resistance value as that before the compression or expansion of the strain gauge 369 occurs. The first strain gauge 369a4 to the fourth strain gauge 369d4 have the same resistance value.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a4 to the fourth strain gauge 369d4 are parallel to the central axes C1 and C2. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first strain gauge 369a4 and the second strain gauge 369b4 are not compressed or expanded in the detection direction, the first detection circuit 373a4 using the strain gauge 369 having such characteristics has the first strain gauge 369a4 and the first strain gauge 369a4. The potential difference between the potential Vab between the two strain gauges 369b4 and the potential Vr between the two fixed resistors R is almost zero.

  When the first strain gauge 369a4 is compressed and the second strain gauge 369b4 is expanded, the resistance value of the first strain gauge 369a4 decreases and the resistance value of the second strain gauge 369b4 increases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a4 is expanded and the second strain gauge 369b4 is compressed, the resistance value of the first strain gauge 369a4 increases and the resistance value of the second strain gauge 369b4 decreases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a4 and the second strain gauge 369b4 are compressed, the resistance value of both the first strain gauge 369a4 and the second strain gauge 369b4 decreases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a4 and the second strain gauge 369b4 are expanded, the resistance value of both the first strain gauge 369a4 and the second strain gauge 369b4 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  The second detection circuit 373b4 operates similarly to the first detection circuit 373a4. That is, when the third strain gauge 369c4 is compressed and the fourth strain gauge 369d4 is expanded, the potential Vcd is increased, the potential Vr is decreased, and a potential difference is generated between the potential Vcd and the potential Vr. When the third strain gauge 369c4 is expanded and the fourth strain gauge 369d4 is compressed, the potential Vcd is decreased, the potential Vr is increased, and a potential difference is generated between the potential Vcd and the potential Vr. When both the third strain gauge 369c4 and the fourth strain gauge 369d4 are compressed and when both the third strain gauge 369c4 and the fourth strain gauge 369d4 are expanded, the potential difference between the potential Vcd and the potential Vr becomes almost zero. .

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a4 and the second strain gauge 369b4 that can measure the potential Vab of the first detection circuit 373a4 and a connection point between the two fixed resistors R that can measure the potential Vr. The output is 373a4 (hereinafter referred to as A output). The connection point between the third strain gauge 369c4 and the fourth strain gauge 369d4 that can measure the potential Vcd of the second detection circuit 373b4 and the connection point of the two fixed resistors R that can measure the potential Vr of the second detection circuit 373b4. Output (hereinafter referred to as B output). The A output and B output become strain information.

  Here, the measurement module strain detection circuit 365 is arranged as shown in FIG. 16 and connected to the first strain gauge 369a4, the second strain gauge 369b4, the third strain gauge 369c4, and the fourth strain gauge 369d4 as shown in FIG. A method for detecting (measuring) the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a4 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a is compressed and thus the resistance value is decreased, and the second strain gauge 369b4 is expanded and the resistance value is increased. Therefore, the output A of the first detection circuit 373a4 is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a4 is expanded and thus the resistance value is increased, and the second strain gauge 369b4 is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a4 is a negative output (the potential Vab is low and the potential Vr is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a4 and the second strain gauge 369b4 are compressed, the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a4 is zero (there is no potential difference between the potential Vab and the potential Vr). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a4 and the second strain gauge 369b4 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a4 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a4 and the second strain gauge 369b4 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a4 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a4 and the second strain gauge 369b4 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a4 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a4 and the second strain gauge 369b4 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a4 is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a4 and the second strain gauge 369b4 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a4 is zero.

  As described above, only the bending deformation x is detected from the A output. That is, the first detection circuit 373a4 is connected to the first strain gauge 369a4 and the second strain gauge 369b4 and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b4 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are expanded, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b4 is zero. When the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are compressed, so that the resistance value decreases. Therefore, the B output of the second detection circuit 373b4 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the third strain gauge 369c4 is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d4 is expanded and the resistance value is increased. Therefore, the output B of the second detection circuit 373b4 is a positive output (the potential Vcd is high and the potential Vr is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the third strain gauge 369c4 is expanded and thus the resistance value is increased, and the fourth strain gauge 369d4 is compressed and the resistance value is decreased. Therefore, the output B of the second detection circuit 373b4 is a negative output (the potential Vcd is low and the potential Vr is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are extended, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b4 is zero. Further, when the right crank 105R is compressed, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are compressed, so that the resistance value decreases. Therefore, the B output of the second detection circuit 373b4 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are extended, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b4 is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the third strain gauge 369c4 and the fourth strain gauge 369d4 are extended, so that the resistance value increases. Therefore, the B output of the second detection circuit 373b4 is zero.

  As described above, the bending deformation y is detected from the B output. That is, the second detection circuit 373b4 is connected to the third strain gauge 369c4 and the fourth strain gauge 369d4, and detects the inward and outward strain generated in the crank 105.

From the A output of the first detection circuit 373a4 and the B output of the second detection circuit 373b4, the propulsive force Ft is expressed by the equation (1) shown in the first embodiment, and the loss force Fr is expressed by the following equation (8). Respectively. The formula (1) is shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s (A−A0) + u (B−B0) [kgf] (8)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  The coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance. It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (8), the A output is used to correct the B output. That is, the measurement module control unit 351 that calculates each formula functions as a correction unit. Thereby, it is possible to eliminate the influence of distortion other than the detection target included in the first detection circuit 373a4 and the second detection circuit 373b4. If the first strain gauge 369a4 and the second strain gauge 369b4 are not displaced in the crank direction (direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary. Further, when the third strain gauge 369c4 and the fourth strain gauge 369d4 are not displaced in the crank direction, Be = B0 and correction by the A output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to the present embodiment, the measurement module 301 includes a first strain gauge 369a4 and a second strain gauge 369b4 provided on the inner surface 119 of the crank 105 of the bicycle 1, and a third strain gauge provided on the upper surface 117 of the crank 105. 369c4, the fourth strain gauge 369d4, the first strain gauge 369a4 and the second strain gauge 369b4 are connected, the first detection circuit 373a4 for detecting the bending deformation x generated in the crank 105, the third strain gauge 369c4 and the second strain gauge 369c4 4 strain gauge 369d4 is connected, and it has 2nd detection circuit 373b4 which detects the bending deformation y which has arisen in the crank 105. FIG. The first strain gauge 369a4 to the fourth strain gauge 369d4 are provided so that the detection direction is parallel to the longitudinal direction of the crank 105. Thus, the propulsive force Ft and the loss force Fr applied to the crank 105 are measured from the bending deformation x detected by the first detection circuit 373a4 and the bending deformation y detected by the second detection circuit 373b4. be able to. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, by providing the first strain gauge 369a4 and the second strain gauge 369b4 on the inner surface 119 of the crank 105, there is no interference with the user's foot.

  Further, since the first strain gauge 369a4 and the second strain gauge 369b4 are provided so as to be symmetrical with respect to the central axis C1 in the longitudinal direction of the inner surface 119 of the crank 105, the bending deformation x can be detected with high accuracy. it can.

  Further, since the third strain gauge 369c4 and the fourth strain gauge 369d4 are provided so as to be symmetric with respect to the central axis C2 in the longitudinal direction of the upper surface 117 of the crank 105, the bending deformation y can be detected with high accuracy. it can.

  In addition, the first detection circuit 373a4 and the second detection circuit 373b4 are configured by a bridge circuit, and the first strain gauge 369a4 and the second strain gauge 369b4 are serially connected to the power supply in the bridge circuit configuring the first detection circuit 373a4. The third strain gauge 369c4 and the fourth strain gauge 369d4 are connected in series to the power supply in the bridge circuit that constitutes the second detection circuit 373b4, and further, the bridge circuit that constitutes the first detection circuit 373a4 and the first Since the resistance elements other than the first strain gauge 369a4 to the fourth strain gauge 369d4 of the bridge circuit constituting the second detection circuit 373b4 are composed of the fixed resistance R, the bridge circuit detects the bending deformation x and the bending deformation y. The propulsive force Ft with a simple circuit configuration It can be measured loss force Fr.

  Further, since the fixed resistor R is shared by the first detection circuit and the second detection circuit, the first detection circuit and the second detection circuit can be practically made into one circuit, and the circuit is further simplified. Can be.

  Further, since the torsional deformation rz does not act on the calculation of the propulsive force Ft, the propulsive force Ft does not change even if the load position on the pedal 103 changes.

  In the first detection circuit 373a4, the connection order of the first strain gauge 369a4 and the second strain gauge 369b4 may be reversed. In the second detection circuit 373b4, the connection order of the third strain gauge 369c4 and the fourth strain gauge 369d4 may be reversed.

  Next, a measuring apparatus according to a fifth embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 18, the strain gauge 369 of the present embodiment includes a first strain gauge 369a5, a second strain gauge 369b5, a third strain gauge 369c5, and a fourth strain gauge 369d5. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 19 shows the arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. Although not shown in FIG. 19, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. The upper surface 117 of the crank 105 is one of the surfaces extending in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 and orthogonal to the inner surface 119 and the outer surface 120. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a5 and the second strain gauge 369b5 are arranged so as to be orthogonal to each other and overlapped (overlapped). Further, the intermediate direction between the detection direction of the first strain gauge 369a5 and the detection direction of the second strain gauge 369b5 is arranged to be the longitudinal direction of the crank 105. That is, the detection direction of the first strain gauge 369a5 and the axis direction of the crank 105 have an angle of 45 degrees. The detection direction of the second strain gauge 369b5 and the axis direction of the crank 105 have an angle of 45 degrees. Further, the intersection portion where the first strain gauge 369a5 and the second strain gauge 369b5 are overlapped is arranged on the central axis C1 of the inner surface 119. That is, the first strain gauge 369a5 and the second strain gauge 369b5 are disposed so as to be symmetric with respect to the central axis C1.

  The third strain gauge 369c5 is provided on the central axis C1 so that the detection direction is parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119. The fourth strain gauge 369d5 is provided on the central axis C1 with the detection direction perpendicular to the longitudinal direction of the crank 105, that is, perpendicular to the central axis C1 of the inner surface 119.

  That is, the direction parallel to the central axis C1 (the vertical direction in FIG. 19) that is the axis extending in the longitudinal direction of the crank 105, that is, the direction parallel to the longitudinal direction of the crank 105 is the detection direction of the third strain gauge 369c5. Thus, the direction perpendicular to the central axis C1 (lateral direction in FIG. 19), that is, the direction perpendicular to the longitudinal direction of the crank 105 is the detection direction of the fourth strain gauge 369d5. Therefore, the detection directions of the third strain gauge 369c5 and the fourth strain gauge 369d5 are orthogonal to each other.

  In addition, arrangement | positioning of the 1st strain gauge 369a5 thru | or the 4th strain gauge 369d5 is not restricted to FIG. That is, the third strain gauge 369c5 and the fourth strain gauge 369d5 are maintained in a parallel or perpendicular relationship with the central axis C1, the first strain gauge 369a5 and the second strain gauge 369b5 are orthogonal to each other, and the central axes C1 and 45 Other arrangements may be used as long as the degree relationship is maintained. However, the arrangement on the central axis C1 is preferable because each deformation described later can be accurately detected.

  In FIG. 19, the crank 105 is described as a simple rectangular parallelepiped, but the corners may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel or vertical or 45 degrees) with the center axis C1 described above and the first strain gauge 369a5 and the second strain gauge 369b5 are in a relationship orthogonal to each other.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a5, the second strain gauge 369b5, the third strain gauge 369c5, and the fourth strain gauge 369d5, and outputs the strain amount of the strain gauge 369 as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a5 and a second detection circuit 373b5 that are two bridge circuits. On the first system side of the first detection circuit 373a5, the second strain gauge 369b5 and the first strain gauge 369a5 are connected in this order from the power source Vcc. That is, the first strain gauge 369a5 and the second strain gauge 369b5 are connected in series to the power source Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc. On the first system side of the second detection circuit 373b5, the third strain gauge 369c5 and the fourth strain gauge 369d5 are connected in this order from the power source Vcc. That is, the third strain gauge 369c5 and the fourth strain gauge 369d5 are connected in series with the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power source Vcc.

  That is, the two fixed resistors R are shared by the first detection circuit 373a5 and the second detection circuit 373b5. Here, the two fixed resistors R have the same resistance value. The two fixed resistors R have the same resistance value as that before the compression or expansion of the strain gauge 369 occurs. The first strain gauge 369a5 to the fourth strain gauge 369d5 have the same resistance value.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends. As described above, the third strain gauge 369c5 is parallel to the central axis C1, and the fourth strain gauge 369d5 is perpendicular to the central axis C1. Direction. The first strain gauge 369a5 and the second strain gauge 369b5 are oriented at 45 degrees. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first detection circuit 373a5 using the strain gauge 369 having such characteristics is not compressed or expanded in the detection direction of the first strain gauge 369a5 and the second strain gauge 369b5, the first detection gauge 369a5 and the first strain gauge 369a5 The potential difference between the potential Vab between the two strain gauges 369b5 and the potential Vr between the two fixed resistors R is substantially zero.

  When the first strain gauge 369a5 is compressed and the second strain gauge 369b5 is expanded, the resistance value of the first strain gauge 369a5 decreases and the resistance value of the second strain gauge 369b5 increases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a5 is expanded and the second strain gauge 369b5 is compressed, the resistance value of the first strain gauge 369a5 increases and the resistance value of the second strain gauge 369b5 decreases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a5 and the second strain gauge 369b5 are compressed, the resistance value of both the first strain gauge 369a5 and the second strain gauge 369b5 decreases, so the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a5 and the second strain gauge 369b5 are stretched, the resistance value of both the first strain gauge 369a5 and the second strain gauge 369b5 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  The second detection circuit 373b5 operates similarly to the first detection circuit 373a5. That is, when the third strain gauge 369c5 is compressed and the fourth strain gauge 369d5 is expanded, the potential Vcd is increased, the potential Vr is decreased, and a potential difference is generated between the potential Vcd and the potential Vr. When the third strain gauge 369c5 is expanded and the fourth strain gauge 369d5 is compressed, the potential Vcd is decreased, the potential Vr is increased, and a potential difference is generated between the potential Vcd and the potential Vr. When both the third strain gauge 369c5 and the fourth strain gauge 369d5 are compressed and when both the third strain gauge 369c5 and the fourth strain gauge 369d5 are expanded, the potential difference between the potential Vcd and the potential Vr becomes almost zero. .

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a5 and the second strain gauge 369b5 that can measure the potential Vab of the first detection circuit 373a5, and a connection point between the two fixed resistors R that can measure the potential Vr. The output of 373a5 (hereinafter referred to as A output). The connection point between the third strain gauge 369c5 and the fourth strain gauge 369d5 that can measure the potential Vcd of the second detection circuit 373b5 and the connection point of the two fixed resistors R that can measure the potential Vr of the second detection circuit 373b5. Output (hereinafter referred to as B output). The A output and B output become strain information.

  Here, the measurement module strain detection circuit 365 is arranged as shown in FIG. 19 and connected to the first strain gauge 369a5, the second strain gauge 369b5, the third strain gauge 369c5, and the fourth strain gauge 369d5 as shown in FIG. A method for detecting (measuring) the bending deformation x, the bending deformation y, the tensile deformation z, and the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a5 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, as shown in FIG. 21, one end of the first strain gauge 369a5 is expanded, but the other end is compressed. As a result, both expansion and compression occur in the first strain gauge 369a5, and the resistance value of the first strain gauge 369a5 does not change. The same applies to the second strain gauge 369b5. Therefore, the output A of the first detection circuit 373a5 is zero. Similarly, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, both the first strain gauge 369a5 and the second strain gauge 369b5 are both expanded and compressed, and the resistance value does not change. Therefore, the output A of the first detection circuit 373a5 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, both the first strain gauge 369a5 and the second strain gauge 369b5 are stretched, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a5 is zero. Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a5 and the second strain gauge 369b5 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a5 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R expands, both the first strain gauge 369a5 and the second strain gauge 369b5 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a5 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a5 and the second strain gauge 369b5 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a5 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the first strain gauge 369a5 is expanded and thus the resistance value is increased, and the second strain gauge 369b5 is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a5 is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the resistance value decreases because the first strain gauge 369a5 is compressed, and the resistance value is compressed because the second strain gauge 369b5 is expanded. To do. Therefore, the output A of the first detection circuit 373a5 is a negative output (the potential Vab is low and the potential Vr is high).

  As described above, only the torsional deformation rz is detected from the A output. That is, the first detection circuit 373a5 is connected to the first strain gauge 369a5 and the second strain gauge 369b5, and detects a twist direction strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b5 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, since the third strain gauge 369c5 and the fourth strain gauge 369d5 are only bent, the resistance value does not change because they are neither compressed nor expanded in the detection direction. Therefore, the B output of the second detection circuit 373b5 is zero. Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the third strain gauge 369c5 and the fourth strain gauge 369d5 are only bent, so that the resistance value does not change because they are neither compressed nor expanded in the detection direction. Therefore, the B output of the second detection circuit 373b5 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the third strain gauge 369c5 is compressed and thus the resistance value is decreased, and the fourth strain gauge 369d5 is expanded and the resistance value is increased. Therefore, the output B of the second detection circuit 373b5 is a positive output (the potential Vcd is high and the potential Vr is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the third strain gauge 369c5 is expanded and thus the resistance value is increased, and the fourth strain gauge 369d5 is compressed and the resistance value is decreased. Therefore, the output B of the second detection circuit 373b5 is a negative output (the potential Vcd is low and the potential Vr is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is expanded, the third strain gauge 369c5 is expanded and thus the resistance value is increased, and the fourth strain gauge 369d5 is compressed and the resistance value is decreased. Therefore, the B output of the second detection circuit 373b5 is a negative output. Further, when the right crank 105R compresses, the third strain gauge 369c5 is compressed and thus the resistance value decreases, and the fourth strain gauge 369d5 is expanded and the resistance value increases. Therefore, the B output of the second detection circuit 373b5 is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the resistance value increases because the third strain gauge 369c5 is expanded, and the resistance value does not change because the fourth strain gauge 369d5 does not deform in the detection direction. . Therefore, the B output of the second detection circuit 373b5 is a negative output. In addition, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the third strain gauge 369c5 is expanded and thus the resistance value increases, and the fourth strain gauge 369d5 is not deformed in the detection direction and thus the resistance value. Does not change. Therefore, the B output of the second detection circuit 373b5 is a negative output.

  As described above, the bending deformation y, the tensile deformation z, and the torsional deformation rz are detected from the B output. In other words, the second detection circuit 373b5 is connected to the third strain gauge 369c5 and the fourth strain gauge 369d5, and detects the internal / external strain or tensile strain generated in the crank 105.

From the A output of the first detection circuit 373a5 and the B output of the second detection circuit 373b5, the propulsive force Ft and the loss force Fr are respectively expressed by the equations (1) and (2) shown in the first embodiment. calculate. The tensile deformation z is very small compared to the bending deformation y and can be ignored. The expressions (1) and (2) are shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s | A−A0 | + u (B−B0) [kgf] (2)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  Since the coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance, the propulsive force Ft and the loss force Fr can be obtained by substituting A and B into the equations (1) and (2). It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (2), the A output is used to correct the B output. That is, the measurement module control unit 351 that calculates each formula functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a5 and the 2nd detection circuit 373b5 can be excluded. If the first strain gauge 369a5 and the second strain gauge 369b5 are not displaced in the crank direction (the direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to the present embodiment, the measurement module 301 includes a first strain gauge 369a5, a second strain gauge 369b5, a third strain gauge 369c5, and a fourth strain gauge 369d5 provided on the inner surface 119 of the crank 105 of the bicycle 1. A first strain gauge 369a5 and a second strain gauge 369b5 are connected, a first detection circuit 373a5 for detecting torsional deformation rz generated in the crank, a third strain gauge 369c5 and a fourth strain gauge 369d5 are connected, and the crank 105 And a second detection circuit 373b5 for detecting the bending deformation y and the tensile deformation z occurring. The detection directions of the first strain gauge 369a5 and the second strain gauge 369b5 are orthogonal to each other, and the intermediate direction of the detection directions of the first strain gauge 369a5 and the second strain gauge 369b5 is the longitudinal direction of the crank 105. The third strain gauge 369c5 is provided so that its detection direction is parallel to the longitudinal direction of the crank 105, and the fourth strain gauge 369d5 is perpendicular to the longitudinal direction of the crank 105. It is provided to become. By doing so, the propulsive force Ft and the loss force applied to the crank 105 from the torsional deformation rz detected by the first detection circuit 373a5 and the bending deformation y and the tensile deformation z detected by the second detection circuit 373b5. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, since the first strain gauge 369a5 to the fourth strain gauge 369d5 are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface 119 By providing in, it does not interfere with the user's foot.

  Further, since the first strain gauge 369a5 and the second strain gauge 369b5 are overlapped with each other, the size of the strain gauge 369 can be reduced.

  In addition, the first detection circuit 373a5 and the second detection circuit 373b5 are configured by a bridge circuit, and the first strain gauge 369a5 and the second strain gauge 369b5 are serially connected to the power supply in the bridge circuit configuring the first detection circuit 373a5. The third strain gauge 369c5 and the fourth strain gauge 369d5 are connected in series to the power supply in the bridge circuit constituting the second detection circuit 373b5, and further the bridge circuit and the first strain constituting the first detection circuit 373a5 2 Since the resistance elements other than the first strain gauge 369a5 to the fourth strain gauge 369d5 of the bridge circuit constituting the detection circuit 373b5 are configured by the fixed resistance R, the bridge circuit causes the bending deformation x, the bending deformation y, and the tension. Simple circuit that can detect deformation z It can be measured propulsive force Ft and loss force Fr in adult.

  Further, since the fixed resistor R is shared by the first detection circuit and the second detection circuit, the first detection circuit and the second detection circuit can be practically made into one circuit, and the circuit is further simplified. Can be.

  In the above description, the third strain gauge 369c5 and the fourth strain gauge 369d5 are provided as separate elements. However, they may be stacked in a cross shape, for example. By doing so, the size of the strain gauge 369 provided in the crank 105 can be reduced. Further, the first strain gauge 369a5 to the fourth strain gauge 369d5 may all be stacked. In this case, the strain gauge 369 can be made very small. Alternatively, the first strain gauge 369a5 and the second strain gauge 369b5 may be arranged individually without overlapping.

  Further, the order of arrangement of the first strain gauge 369a5 to the fourth strain gauge 369d5 is not limited to the order shown in FIG. 19 and is not particularly limited.

  In FIG. 20, two bridge circuits are combined into one circuit, but may be divided into two bridge circuits as separate circuits. In that case, two fixed resistors R are required for each circuit.

  In the first detection circuit 373a5, the connection order of the first strain gauge 369a5 and the second strain gauge 369b5 may be reversed. In the second detection circuit 373b5, the connection order of the third strain gauge 369c5 and the fourth strain gauge 369d5 may be reversed.

  Next, a measuring apparatus according to a sixth embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 22, the strain gauge 369 according to the present embodiment includes a first strain gauge 369a6, a second strain gauge 369b6, and a third strain gauge 369c6. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 23 shows the arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. Although not shown in FIG. 23, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 protrudes (is connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. The upper surface 117 of the crank 105 is one of the surfaces extending in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 and orthogonal to the inner surface 119 and the outer surface 120. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a6 and the second strain gauge 369b6 have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119 and symmetrical to the central axis C1 of the inner surface 119. It is provided to become. The third strain gauge 369c6 is provided on the center axis C1, and is provided so that the detection direction is perpendicular to the center axis C1 and is sandwiched between the first strain gauge 369a6 and the second strain gauge 369b6.

  That is, the direction parallel to the central axis C1 that is the axis extending in the longitudinal direction of the crank 105 (the longitudinal direction in FIG. 23), that is, the direction parallel to the longitudinal direction of the crank 105 is the first strain gauge 369a6, The direction in which the strain gauge 369b6 is detected and the direction perpendicular to the central axis C1 (the lateral direction in FIG. 23), that is, the direction perpendicular to the longitudinal direction of the crank 105 is the direction in which the third strain gauge 369c6 is detected. Therefore, the detection directions of the first strain gauge 369a6, the second strain gauge 369b6, and the third strain gauge 369c6 are orthogonal to each other.

  In addition, arrangement | positioning of the 1st strain gauge 369a6 thru | or the 3rd strain gauge 369c6 is not restricted to FIG. In other words, other arrangements may be used as long as a parallel or vertical relationship with the central axis C1 is maintained. However, the first strain gauge 369a6 and the second strain gauge 369b6 are arranged symmetrically with respect to the central axis C1, and the third strain gauge 369c6 is arranged on the central axis C1 so that each deformation described later can be accurately performed. It is preferable because it can be detected.

  In FIG. 23, the crank 105 is described as a simple rectangular parallelepiped, but the corners may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel or vertical) with the center axis C1 is shifted.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a6, the second strain gauge 369b6, and the third strain gauge 369c6, and outputs the strain amount of the strain gauge 369 as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a6 and a second detection circuit 373b6 that are two bridge circuits. On the first system side of the first detection circuit 373a6, the first strain gauge 369a6 and the second strain gauge 369b6 are connected in this order from the power supply Vcc side. That is, the first strain gauge 369a6 and the second strain gauge 369b6 are connected in series to the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the power supply Vcc side. On the first system side of the second detection circuit 373b6, the third strain gauge 369c6 and the first detection circuit 373a6 are connected in this order from the power supply Vcc. That is, the first detection circuit 373a6 is connected in series with the third strain gauge 369c6 of the second detection circuit 373b6 and the power supply Vcc. On the second system side, the fixed resistor R and the fixed resistor 2R are connected in this order from the power source Vcc.

  The first detection circuit 373a6 has the power supply Vcc side connected to the third strain gauge 369c6. In this way, when viewed as the second detection circuit 373b6, the power supply Vcc, the third strain gauge 369c6, the first strain gauge 369a6, and the second strain gauge 369b6 are connected in series in this order. Further, the three fixed resistors R have the same resistance value and are much larger than the resistance values of the first strain gauge 369a6 to the third strain gauge 369c6 (for example, when the resistance value of the strain gauge 369 is 1 kΩ, the resistance of the fixed resistor R) The value is 100 kΩ or more). That is, when the resistance value of the first strain gauge 369a6 to the third strain gauge 369c6 is GR, the relationship R >> GR is satisfied. The fixed resistor 2R has a resistance value twice that of the fixed resistor R. The first strain gauge 369a6 to the third strain gauge 369c6 have the same resistance value. By doing so, almost no current flows through the fixed resistor R of the first detection circuit 373a6 when there is no load, and the magnitude of the current flowing through the first strain gauge 369a6 to the third strain gauge 369c6 is made equal. Can do.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a6 and the second strain gauge 369b6 are parallel to the central axis C1, and the third strain gauge 369c6 is The direction is perpendicular to the central axis C1. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  The first detection circuit 373a6 using the strain gauge 369 having such characteristics has the first strain gauge 369a6 and the first strain gauge 369a6 when the first strain gauge 369a6 and the second strain gauge 369b6 are not compressed or expanded in the detection direction. The potential difference between the potential Vab between the two strain gauges 369b6 and the potential Vr between the two fixed resistors R is substantially zero.

  When the first strain gauge 369a6 is compressed and the second strain gauge 369b6 is expanded, the resistance value of the first strain gauge 369a6 decreases and the resistance value of the second strain gauge 369b6 increases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a6 is expanded and the second strain gauge 369b6 is compressed, the resistance value of the first strain gauge 369a6 increases and the resistance value of the second strain gauge 369b6 decreases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a6 and the second strain gauge 369b6 are compressed, the resistance value of both the first strain gauge 369a6 and the second strain gauge 369b6 decreases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a6 and the second strain gauge 369b6 are extended, the resistance value of both the first strain gauge 369a6 and the second strain gauge 369b6 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  When the second detection circuit 373b6 is not compressed or expanded in the detection direction of the third strain gauge 369c6, the potential Vc between the third strain gauge 369c6 and the first detection circuit 373a6, the fixed resistance R, and the fixed resistance The potential difference with the potential V2r between 2R is almost zero.

  When the third strain gauge 369c6 is compressed, the resistance value of the third strain gauge 369c6 decreases, so the potential Vc increases and the potential V2r does not change. That is, a potential difference is generated between the potential Vc and the potential V2r. When the third strain gauge 369c6 is extended, the resistance value of the third strain gauge 369c6 increases, so the potential Vc decreases and the potential V2r does not change. That is, a potential difference is generated between the potential Vc and the potential V2r.

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a6 and the second strain gauge 369b6 that can measure the potential Vab of the first detection circuit 373a6 and a connection point between the two fixed resistors R that can measure the potential Vr. The output of 373a6 (hereinafter referred to as A output). Second detection is made of a connection point between the third strain gauge 369c6 and the first detection circuit 373a6 capable of measuring the potential Vc of the second detection circuit 373b6, and a connection point between the fixed resistor R and the fixed resistor 2R capable of measuring the potential V2r. It is assumed that the output of the circuit 373b6 (hereinafter referred to as B output). The A output and B output become strain information.

  Here, as shown in FIG. 23, the measurement module strain detection circuit 365 to which the first strain gauge 369a6, the second strain gauge 369b6, and the third strain gauge 369c6 are connected as shown in FIG. A method for detecting (measuring) the deformation y, the tensile deformation z, and the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a6 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a6 is compressed and thus the resistance value is decreased, and the second strain gauge 369b6 is expanded and the resistance value is increased. Therefore, the output A of the first detection circuit 373a6 is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a6 is expanded and thus the resistance value is increased, and the second strain gauge 369b6 is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a6 is a negative output (the potential Vab is low and the potential Vr is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, both the first strain gauge 369a6 and the second strain gauge 369b6 are compressed, so the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a6 is zero (there is no potential difference between the potential Vab and the potential Vr). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a6 and the second strain gauge 369b6 are stretched, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a6 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a6 and the second strain gauge 369b6 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a6 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a6 and the second strain gauge 369b6 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a6 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a6 and the second strain gauge 369b6 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a6 is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a6 and the second strain gauge 369b6 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a6 is zero.

  As described above, only the bending deformation x is detected from the A output. That is, the first detection circuit 373a6 is connected to the first strain gauge 369a6 and the second strain gauge 369b6, and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a6 is compressed and thus the resistance value is decreased. The second strain gauge 369b6 is expanded and the resistance value is increased. Since the strain gauge 369c6 is not compressed or expanded in the detection direction, the resistance value does not change. Therefore, the B output of the second detection circuit 373b6 is zero. Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a6 is expanded and thus the resistance value is increased, and the second strain gauge 369b6 is compressed and the resistance value is decreased, Since the third strain gauge 369c6 is not compressed or expanded in the detection direction, the resistance value does not change. Therefore, the B output of the second detection circuit 373b6 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, the first strain gauge 369a6 and the second strain gauge 369b6 are compressed, so that the resistance value decreases, and the third strain gauge 369c6 is expanded, so that the resistance value is increased. Will increase. Therefore, the output B of the second detection circuit 373b6 is a positive output (the potential Vc is high and the potential V2r is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, the first strain gauge 369a6 and the second strain gauge 369b6 are expanded, so that the resistance value is increased, and the third strain gauge 369c6 is compressed. The resistance value decreases. Therefore, the output B of the second detection circuit 373b6 is a negative output (the potential Vc is low and the potential V2r is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is expanded, the first strain gauge 369a6 and the second strain gauge 369b6 are expanded, so that the resistance value is increased, and the third strain gauge 369c6 is compressed, so that the resistance value is decreased. Therefore, the B output of the second detection circuit 373b6 is a negative output. When the right crank 105R is compressed, the first strain gauge 369a6 and the second strain gauge 369b6 are compressed and thus the resistance value is decreased, and the third strain gauge 369c6 is expanded and the resistance value is increased. Therefore, the B output of the second detection circuit 373b6 is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6 (b), the first strain gauge 369a6 and the second strain gauge 369b6 are expanded, so that the resistance value increases, and the third strain gauge 369c6 is compressed in the detection direction. Since it is not stretched, the resistance value does not change. Therefore, the B output of the second detection circuit 373b6 is a negative output. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the first strain gauge 369a6 and the second strain gauge 369b6 are expanded, so that the resistance value increases, and the third strain gauge 369c6 is in the detection direction. The resistance value does not change because neither compression nor expansion is performed. Therefore, the B output of the second detection circuit 373b6 is a negative output.

  As described above, the bending deformation y, the tensile deformation z, and the torsional deformation rz are detected from the B output. That is, the second detection circuit 373b6 is connected to the third strain gauge 369c6, and detects the inward / outward strain or the tensile strain generated in the crank 105.

From the A output of the first detection circuit 373a6 and the B output of the second detection circuit 373b6, the propulsive force Ft and the loss force Fr are respectively expressed by the expressions (1) and (2) shown in the first embodiment. calculate. The tensile deformation z is very small compared to the bending deformation y and can be ignored. The expressions (1) and (2) are shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s | A−A0 | + u (B−B0) [kgf] (2)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  Since the coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance, the propulsive force Ft and the loss force Fr can be obtained by substituting A and B into the equations (1) and (2). It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (2), the A output is used to correct the B output. That is, the measurement module control unit 351 that calculates each formula functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a6 or the 2nd detection circuit 373b6 can be excluded. If the first strain gauge 369a6 and the second strain gauge 369b6 are not displaced in the crank direction (the direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to the present embodiment, the measurement module 301 includes a first strain gauge 369a6, a second strain gauge 369b6, a third strain gauge 369c6, a first strain gauge 369a6 and a first strain gauge 369a6 provided on the inner surface 119 of the crank 105 of the bicycle 1. 2 strain gauges 369b6 are connected, and a first detection circuit 373a6 that detects bending deformation x generated in the crank 105 and a third strain gauge 369c6 are connected, and bending deformation y and tensile deformation z generated in the crank 105 are detected. And a second detection circuit 373b6 for detection. The first strain gauge 369a6 and the second strain gauge 369b6 are provided so that the detection direction is parallel to the longitudinal direction of the crank 105, and the third strain gauge 369c6 is detected with respect to the longitudinal direction of the crank 105. It is provided so that the direction is vertical. Thus, the propulsive force Ft and the loss force applied to the crank 105 from the bending deformation x detected by the first detection circuit 373a6 and the bending deformation y and the tensile deformation z detected by the second detection circuit 373b6. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. Further, since the first strain gauge 369a6 to the third strain gauge 369c6 are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface 119 By providing in, it does not interfere with the user's foot.

  Further, the first detection circuit 373a6 and the second detection circuit 373b6 are configured by a bridge circuit, and the first strain gauge 369a6 and the second strain gauge 369b6 are serially connected to the power supply Vcc in the bridge circuit configuring the first detection circuit 373a6. The third strain gauge 369c6 is connected in series to the power supply Vcc in the bridge circuit constituting the second detection circuit 373b6, and further the bridge circuit and the second detection circuit 373b6 constituting the first detection circuit 373a6 Since the resistance elements other than the first strain gauge 369a6 to the third strain gauge 369c6 of the bridge circuit that constitutes are configured by the fixed resistance R and the fixed resistance 2R, the bridge circuit causes the bending deformation x, the bending deformation y, and the tension. A simple circuit structure that can detect deformation z. In can be measured propulsive force Ft and loss force Fr.

  Further, since the first detection circuit 373a6 is connected in series to the third strain gauge 369c6 of the second detection circuit 373b6 and the power supply Vcc, the first detection circuit 373a6 and the second detection circuit 373b6 are combined into one circuit. The circuit configuration can be further simplified.

  Further, when the resistance value of the fixed resistor R is R and the resistance values of the first strain gauge 369a6 to the third strain gauge 369c6 are GR, R and GR have a relationship of R >> GR. The currents flowing through the strain gauge 369a6 to the third strain gauge 369c6 can be made equal. Therefore, the B output is in an equilibrium state when there is no load.

  Since the first strain gauge 369a6 and the second strain gauge 369b6 are provided so as to be symmetric with respect to the central axis C1, the bending deformation x can be detected with high accuracy.

  In this embodiment, as shown in FIG. 25, the measurement module strain detection circuit 365 may be connected to the changeover switch 3746 in parallel with the third strain gauge 369c. That is, it has switching means for directly connecting the first detection circuit 373a to the power supply Vcc.

  When the changeover switch 3746 is OFF, it is the same as FIG. When the changeover switch 3746 is ON, the power supply Vcc side of the first detection circuit 373a6 is directly connected to the power supply Vcc. Therefore, the output voltage value of A output can be increased. Therefore, the influence of noise can be reduced.

  In the above description, the first strain gauge 369a6, the second strain gauge 369b6, and the third strain gauge 369c6 are provided as separate elements. For example, the first strain gauge 369a6 and the third strain gauge 369c6 or the second strain gauge 369c6 are provided. The strain gauge 369a6 and the third strain gauge 369c6 may overlap each other in a cross shape. By doing so, the size of the strain gauge 369 provided in the crank 105 can be reduced.

  Further, the order of the arrangement of the first strain gauge 369a6 to the third strain gauge 369c6 is not limited to the order shown in FIG.

  In FIG. 24, two bridge circuits are combined into one circuit, but may be divided into two bridge circuits as separate circuits. In that case, in the second detection circuit 373b6, it is necessary to connect the same resistor as the fixed resistor 2R to the portion where the first detection circuit 373a6 was connected.

  In the first detection circuit 373a6, the connection order of the first strain gauge 369a6 and the second strain gauge 369b6 may be reversed. In the second detection circuit 373b6, the connection order of the third strain gauge 369c6 and the first detection circuit 373a6 may be reversed. However, when the connection order of the third strain gauge 369c6 and the first detection circuit 373a6 is reversed, it is necessary to reverse the connection order of the fixed resistor R and the fixed resistor 2R.

  Next, a measuring apparatus according to a seventh embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 26, the strain gauge 369 of the present embodiment includes a first strain gauge 369a7 and a second strain gauge 369b7. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 27 shows the arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. Although not shown in FIG. 27, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. The upper surface 117 of the crank 105 is one of the surfaces extending in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 and orthogonal to the inner surface 119 and the outer surface 120. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a7 and the second strain gauge 369b7 have a detection direction parallel to the longitudinal direction of the crank 105, that is, parallel to the central axis C1 of the inner surface 119 and symmetrical to the central axis C1 of the inner surface 119. It is provided to become.

  That is, the direction parallel to the central axis C1 that is the axis extending in the longitudinal direction of the crank 105 (the longitudinal direction in FIG. 27), that is, the direction parallel to the longitudinal direction of the crank 105 is the first strain gauge 369a7, This is the detection direction of the strain gauge 369b7.

  In addition, arrangement | positioning of the 1st strain gauge 369a7 and the 2nd strain gauge 369b7 is not restricted to FIG. That is, other arrangements may be used as long as the parallel relationship with the central axis C1 is maintained. However, it is preferable to arrange the first strain gauge 369a7 and the second strain gauge 369b7 symmetrically with respect to the central axis C1, because each deformation described later can be detected with high accuracy.

  In FIG. 27, the crank 105 is described as a simple rectangular parallelepiped, but the corners may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship (parallel) with the center axis C1 described above shifts.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a7 and the second strain gauge 369b7, and the strain amount of the strain gauge 369 is output as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a7 and a second detection circuit 373b7 that are two bridge circuits. On the first system side of the first detection circuit 373a7, the first strain gauge 369a7 and the second strain gauge 369b7 are connected in this order from the constant current power source 3747 side. That is, the first strain gauge 369a7 and the second strain gauge 369b7 are connected in series to the constant current power source 374. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the constant current power source 3747 side. On the first system side of the second detection circuit 373b7, the first detection circuit 373a7 is connected to the constant current power source 3747. That is, the first strain gauge 369a7 and the second strain gauge 369b7 are connected in series to the constant current power source 3747 in the bridge circuit constituting the first detection circuit 373a7. On the second system side, the fixed resistor R1 and the fixed resistor R2 are connected in this order from the constant voltage power source Vcc. The first detection circuit 373a7 functions as a resistor in the bridge circuit constituting the second detection circuit 373b7. That is, the first detection circuit 373a7 functions as one of the resistors in the bridge circuit that constitutes the second detection circuit 373b7.

  The first detection circuit 373a7 is directly connected to the constant current power supply 3747 side. By doing in this way, the change of resistance value of the 1st strain gauge 369a7 and the 2nd strain gauge 369b7 can be taken out directly in B output mentioned below. That is, by using the constant current power source 3747, a potential V1 (see FIG. 28) to be described later can be changed according to the operation of the first detection circuit 373a7, so that a distortion occurs between the power source and the first detection circuit 373a7. There is no need to provide a gauge element. Note that the two fixed resistors R have the same resistance value. The first strain gauge 369a7 and the second strain gauge 369b7 have the same resistance value. Further, it is desirable that the fixed resistors R1 and R2 have resistance values such that the potential of V2 (see FIG. 28), which will be described later, becomes the same potential as the potential of V1 (see FIG. 28) in a no-load state.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a7 and the second strain gauge 369b7 are parallel to the central axis C1. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first detection circuit 373a7 using the strain gauge 369 having such characteristics is not compressed or expanded in the detection direction of the first strain gauge 369a7 and the second strain gauge 369b7, The potential difference between the potential Vab between the two strain gauges 369b7 and the potential Vr between the two fixed resistors R is substantially zero.

  When the first strain gauge 369a7 is compressed and the second strain gauge 369b7 is expanded, the resistance value of the first strain gauge 369a7 decreases and the resistance value of the second strain gauge 369b7 increases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a7 is expanded and the second strain gauge 369b7 is compressed, the resistance value of the first strain gauge 369a7 increases and the resistance value of the second strain gauge 369b7 decreases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a7 and the second strain gauge 369b7 are compressed, the resistance value of both the first strain gauge 369a7 and the second strain gauge 369b7 decreases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a7 and the second strain gauge 369b7 are extended, the resistance value of both the first strain gauge 369a7 and the second strain gauge 369b7 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  When the resistance values of the first strain gauge 369a7 and the second strain gauge 369b7 of the first detection circuit 373a7 increase, the second detection circuit 373b7 has a potential V1 between the constant current power supply 3747 and the first detection circuit 373a7. The potential V2 between the fixed resistor R1 and the fixed resistor R2 does not change. That is, a potential difference is generated between the potential V1 and the potential V2. When the resistance values of the first strain gauge 369a7 and the second strain gauge 369b7 of the first detection circuit 373a7 decrease, the potential V1 becomes low and the potential V2 does not change. That is, a potential difference is generated between the potential V1 and the potential V2. When the resistance values of the first strain gauge 369a7 and the second strain gauge 369b7 of the first detection circuit 373a7 do not change, or when one increases and the other decreases, neither the potentials V1 and V2 change. That is, the potential difference between the potential V1 and the potential V2 is almost zero.

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a7 and the second strain gauge 369b7 that can measure the potential Vab of the first detection circuit 373a7, and a connection point between the two fixed resistors R that can measure the potential Vr. The output of 373a7 (hereinafter referred to as A output). A connection point between the constant current power source 3747 capable of measuring the potential V1 of the second detection circuit 373b7 and the first detection circuit 373a7, and a connection point between the fixed resistance R1 and the fixed resistance R2 capable of measuring the potential V2 are provided in the second detection circuit. The output is 373b7 (hereinafter referred to as B output). The A output and B output become strain information.

  Here, the bending deformation x, the bending deformation y, and the tensile deformation z are performed by the measurement module strain detection circuit 365 arranged as shown in FIG. 27 and connected to the first strain gauge 369a7 and the second strain gauge 369b7 as shown in FIG. A method for detecting (measuring) the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a7 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a7 is compressed and thus the resistance value decreases, and the second strain gauge 369b7 is expanded and the resistance value increases. Therefore, the output A of the first detection circuit 373a7 is a positive output (the potential Vab is high and the potential Vr is low). Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a7 is expanded and thus the resistance value is increased, and the second strain gauge 369b7 is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a7 is a negative output (the potential Vab is low and the potential Vr is high).

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a7 and the second strain gauge 369b7 are compressed, the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a7 is zero (there is no potential difference between the potential Vab and the potential Vr). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a7 and the second strain gauge 369b7 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a7 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a7 and the second strain gauge 369b7 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a7 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a7 and the second strain gauge 369b7 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a7 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a7 and the second strain gauge 369b7 are extended, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a7 is zero. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a7 and the second strain gauge 369b7 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a7 is zero.

  As described above, only the bending deformation x is detected from the A output. That is, the first detection circuit 373a7 is connected to the first strain gauge 369a7 and the second strain gauge 369b7, and detects the rotational strain generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b7 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, the first strain gauge 369a7 is compressed and thus the resistance value decreases, and the second strain gauge 369b7 is expanded and the resistance value increases. Therefore, since the potential V1 does not change, the B output of the second detection circuit 373b7 becomes zero. Further, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, the first strain gauge 369a7 is expanded and thus the resistance value is increased, and the second strain gauge 369b7 is compressed and the resistance value is decreased. Therefore, since the potential V1 does not change, the B output of the second detection circuit 373b7 becomes zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a7 and the second strain gauge 369b7 are compressed, the resistance value of both decreases. Therefore, the output B of the second detection circuit 373b7 is a positive output (the potential V1 is high and the potential V2 is low). Further, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a7 and the second strain gauge 369b7 are expanded, so that the resistance value of both increases. Therefore, the output B of the second detection circuit 373b7 is a negative output (the potential V1 is low and the potential V2 is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R is extended, both the first strain gauge 369a7 and the second strain gauge 369b7 are extended, so that the resistance value of both increases. Therefore, the B output of the second detection circuit 373b7 is a negative output. Further, when the right crank 105R is compressed, both the first strain gauge 369a7 and the second strain gauge 369b7 are compressed, so that the resistance value of both decreases. Therefore, the B output of the second detection circuit 373b7 is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, both the first strain gauge 369a7 and the second strain gauge 369b7 are extended, so that the resistance value of both increases. Therefore, the B output of the second detection circuit 373b7 is a negative output. Further, when the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, both the first strain gauge 369a7 and the second strain gauge 369b7 are expanded, so that the resistance value of both increases. Therefore, the B output of the second detection circuit 373b7 is a negative output.

  As described above, the bending deformation y, the tensile deformation z, and the torsional deformation rz are detected from the B output. That is, the second detection circuit 373b7 is connected to the first detection circuit 373a7 and the constant current power source 3747, and detects the internal / external strain or tensile strain generated in the crank 105.

From the A output of the first detection circuit 373a7 and the B output of the second detection circuit 373b7, the propulsive force Ft and the loss force Fr are respectively expressed by the equations (1) and (2) shown in the first embodiment. calculate. The tensile deformation z is very small compared to the bending deformation y and can be ignored. The expressions (1) and (2) are shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s | A−A0 | + u (B−B0) [kgf] (2)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  Since the coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance, the propulsive force Ft and the loss force Fr can be obtained by substituting A and B into the equations (1) and (2). It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (2), the A output is used to correct the B output. That is, the measurement module control unit 351 that calculates each formula functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a7 or the 2nd detection circuit 373b7 can be excluded. If the first strain gauge 369a7 and the second strain gauge 369b7 are not displaced in the crank direction (the direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to the present embodiment, the measurement module 301 includes a first strain gauge 369a7 and a second strain gauge 369b7 provided on the inner surface 119 of the crank 105 of the bicycle 1, a first strain gauge 369a7, and a second strain gauge 369b7. A first detection circuit 373a7 for detecting a bending deformation x generated in the crank 105, to which a current power source 374 is connected, a first detection circuit 373a7, and a bending deformation y generated in the crank 105 to which a constant current power source 374 is connected. And a second detection circuit 373b7 for detecting the tensile deformation z. The first strain gauge 369a7 and the second strain gauge 369b7 are provided so that the detection direction is parallel to the longitudinal direction of the crank 105. Thus, the propulsive force Ft and the loss force applied to the crank 105 from the bending deformation x detected by the first detection circuit 373a7 and the bending deformation y and the tensile deformation z detected by the second detection circuit 373b7. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. In addition, since the constant current power source 3747 is used, the number of strain gauge elements can be reduced. Furthermore, since the first strain gauge 369a7 and the second strain gauge 369b7 are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface 119 By providing in, it does not interfere with the user's foot.

  Further, the first detection circuit 373a7 and the second detection circuit 373b7 are configured by a bridge circuit, and the first strain gauge and the second strain gauge are serially connected to the constant current power source 3747 in the bridge circuit configuring the first detection circuit 373a7. In addition, a resistance element other than the first strain gauge 369a7 and the second strain gauge 369b7 of the bridge circuit constituting the first detection circuit 373a7 and the bridge circuit constituting the second detection circuit 373b7 is connected to Since it is configured by the resistor R1 and the fixed resistor R2, the bending deformation x, the bending deformation y, and the tensile deformation z can be detected by the bridge circuit, and the propulsive force Ft and the loss force Fr are measured with a simple circuit configuration. be able to.

  Since the first strain gauge 369a7 and the second strain gauge 369b7 are provided so as to be symmetric with respect to the central axis C1, the bending deformation x can be detected with high accuracy.

  In the first detection circuit 373a7, the connection order of the first strain gauge 369a7 and the second strain gauge 369b7 may be reversed.

  Next, a measuring apparatus according to an eighth embodiment of the present invention will be described with reference to FIGS. The same parts as those in the first embodiment described above are denoted by the same reference numerals and description thereof is omitted.

  In the present embodiment, the configuration of the measurement module strain detection circuit 365 of the measurement module 301 is different from the arrangement of the strain gauges 369. As shown in FIG. 29, the strain gauge 369 of the present embodiment includes a first strain gauge 369a8 and a second strain gauge 369b8. Each terminal of the strain gauge 369 is connected to the measurement module strain detection circuit 365.

  FIG. 30 shows the arrangement of the strain gauge 369 on the crank 105 in this embodiment. The strain gauge 369 is bonded to the inner surface 119 of the crank 105. The inner surface of the crank 105 is a surface on which the crankshaft 107 is protruded (connected), and is a surface (side surface) parallel to a plane including a circle defined by the rotational motion of the crank 105. Although not shown in FIG. 30, the outer surface 120 of the crank 105 is a surface on which the pedal crankshaft 115 is protruded (connected) so as to face the inner surface 119. That is, it is a surface on which the pedal 103 is rotatably provided. The upper surface 117 of the crank 105 is one of the surfaces extending in the longitudinal direction in the same direction as the inner surface 119 and the outer surface 120 and orthogonal to the inner surface 119 and the outer surface 120. A lower surface 118 of the crank 105 is a surface facing the upper surface 117.

  The first strain gauge 369a8 and the second strain gauge 369b8 are arranged so as to be orthogonal to each other and overlapped (overlapped). Further, the intermediate direction between the detection direction of the first strain gauge 369a8 and the detection direction of the second strain gauge 369b8 is arranged to be the longitudinal direction of the crank 105. That is, the detection direction of the first strain gauge 369a8 and the direction of the central axis C1 of the crank 105 have an angle of 45 degrees. The detection direction of the second strain gauge 369b8 and the direction of the central axis C1 of the crank 105 have an angle of 45 degrees. Further, the intersection portion where the first strain gauge 369a8 and the second strain gauge 369b8 are overlapped is arranged on the central axis C1 of the inner surface 119. That is, the first strain gauge 369a8 and the second strain gauge 369b8 are arranged so as to be symmetric about the central axis C1.

  In addition, arrangement | positioning of the 1st strain gauge 369a8 and the 2nd strain gauge 369b8 is not restricted to FIG. In other words, the first strain gauge 369a8 and the second strain gauge 369b8 may be in other arrangements as long as they are orthogonal to each other and the relationship between the central axis C1 and 45 degrees is maintained. However, the arrangement on the central axis C1 is preferable because each deformation described later can be accurately detected.

  In FIG. 30, the crank 105 is described as a simple rectangular parallelepiped, but the corner may be rounded or a part of the surface may be configured by a curved surface depending on the design or the like. Even in such a case, each deformation described later can be detected by arranging the strain gauge 369 so as to maintain the above-described arrangement as much as possible. However, the detection accuracy decreases as the relationship with the central axis C1 (45 degrees) and the relationship orthogonal to each other shift.

  The measurement module strain detection circuit 365 is connected to the first strain gauge 369a8 and the second strain gauge 369b8, and the strain amount of the strain gauge 369 is output as a voltage. The output of the measurement module strain detection circuit 365 is converted from analog information to strain information that is digital information by the measurement module A / D 363. The strain information signal is output to the measurement module storage unit 353. The strain information signal input to the measurement module storage unit 353 is stored in the measurement module RAM 355 as strain information.

  The measurement module strain detection circuit 365 is shown in FIG. The measurement module strain detection circuit 365 includes a first detection circuit 373a8 and a second detection circuit 373b8 which are two bridge circuits. On the first system side of the first detection circuit 373a8, the second strain gauge 369b8 and the first strain gauge 369a8 are connected in this order from the constant current power source 3748 side. That is, the first strain gauge 369a8 and the second strain gauge 369b8 are connected in series to the constant current power source 3748. On the second system side, the fixed resistor R and the fixed resistor R are connected in this order from the constant current power source 3748 side. On the first system side of the second detection circuit 373b8, the first detection circuit 373a8 is connected to the constant current power source 3748. That is, the first strain gauge 369a8 and the second strain gauge 369b8 are connected in series to the constant current power source 3748 in the bridge circuit constituting the first detection circuit 373a8. On the second system side, the fixed resistor R1 and the fixed resistor R2 are connected in this order from the constant voltage power source Vcc. The first detection circuit 373a8 functions as a resistor in the bridge circuit constituting the second detection circuit 373b8. That is, the first detection circuit 373a8 functions as one of the resistors in the bridge circuit constituting the second detection circuit 373b8.

  The first detection circuit 373a8 is directly connected to the constant current power supply 3748 side. By doing in this way, the change of resistance value of the 1st strain gauge 369a8 and the 2nd strain gauge 369b8 can be taken out directly in B output mentioned below. That is, by using the constant current power supply 374, a potential V1 (see FIG. 31) described later can be changed according to the operation of the first detection circuit 373a8, so that a distortion occurs between the power supply and the first detection circuit 373a8. There is no need to provide a gauge element. Note that the two fixed resistors R have the same resistance value. The first strain gauge 369a8 and the second strain gauge 369b8 have the same resistance value. Further, it is desirable that the fixed resistors R1 and R2 have resistance values such that the potential of V2 (see FIG. 31), which will be described later, becomes the same potential as the potential of V1 (see FIG. 31) in a no-load state.

  As is well known, the resistance value of the strain gauge 369 decreases when it is compressed, and increases when it is expanded. This change in resistance value is proportional when the amount of change is small. The detection direction of the strain gauge 369 is the direction in which the wiring extends, and as described above, the first strain gauge 369a8 and the second strain gauge 369b8 are parallel to the central axis C1. When compression or expansion occurs in a direction other than the detection direction, the strain gauge 369 does not change its resistance value.

  When the first detection circuit 373a8 using the strain gauge 369 having such characteristics is not compressed or expanded in the detection direction of the first strain gauge 369a8 and the second strain gauge 369b8, the first detection gauge 369a8 and the first strain gauge 369a8 The potential difference between the potential Vab between the two strain gauges 369b8 and the potential Vr between the two fixed resistors R is almost zero.

  When the first strain gauge 369a8 is compressed and the second strain gauge 369b8 is expanded, the resistance value of the first strain gauge 369a8 decreases and the resistance value of the second strain gauge 369b8 increases. The potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr. When the first strain gauge 369a8 is expanded and the second strain gauge 369b8 is compressed, the resistance value of the first strain gauge 369a8 increases and the resistance value of the second strain gauge 369b8 decreases. It becomes higher and the potential Vr does not change. That is, a potential difference is generated between the potential Vab and the potential Vr.

  When both the first strain gauge 369a8 and the second strain gauge 369b8 are compressed, the resistance value of both the first strain gauge 369a8 and the second strain gauge 369b8 decreases, so the potential difference between the potential Vab and the potential Vr is almost zero. It becomes. When both the first strain gauge 369a8 and the second strain gauge 369b8 are stretched, the resistance value of both the first strain gauge 369a8 and the second strain gauge 369b8 increases, so that the potential difference between the potential Vab and the potential Vr is almost zero. It becomes.

  When the resistance values of the first strain gauge 369a8 and the second strain gauge 369b8 of the first detection circuit 373a8 increase, the second detection circuit 373b8 has a potential V1 between the constant current power supply 3748 and the first detection circuit 373a8. The potential V2 between the fixed resistor R1 and the fixed resistor R2 does not change. That is, a potential difference is generated between the potential V1 and the potential V2. When the resistance values of the first strain gauge 369a8 and the second strain gauge 369b8 of the first detection circuit 373a8 decrease, the potential V1 becomes low and the potential V2 does not change. That is, a potential difference is generated between the potential V1 and the potential V2. When the resistance values of the first strain gauge 369a8 and the second strain gauge 369b8 of the first detection circuit 373a8 do not change, or when one increases and the other decreases, the potentials V1 and V2 do not change. That is, the potential difference between the potential V1 and the potential V2 is almost zero.

  Therefore, the first detection circuit includes a connection point between the first strain gauge 369a8 and the second strain gauge 369b8 capable of measuring the potential Vab of the first detection circuit 373a8, and a connection point between the two fixed resistors R capable of measuring the potential Vr. The output is 373a8 (hereinafter referred to as A output). The second detection circuit includes a connection point between the constant current power source 3748 capable of measuring the potential V1 of the second detection circuit 373b8 and the first detection circuit 373a8, and a connection point between the fixed resistance R1 and the fixed resistance R2 capable of measuring the potential V2. The output is 373b8 (hereinafter referred to as B output). The A output and B output become strain information.

  Here, the bending deformation x, the bending deformation y, and the tensile deformation z are performed by the measurement module strain detection circuit 365 that is arranged as shown in FIG. 30 and to which the first strain gauge 369a8 and the second strain gauge 369b8 are connected as shown in FIG. A method for detecting (measuring) the torsional deformation rz will be described.

  First, how each deformation is detected (measured) in the output A of the first detection circuit 373a8 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, as shown in FIG. 21, one end of the first strain gauge 369a8 is expanded, while the other end is compressed (FIG. Although it is an explanatory view of the embodiment, the present embodiment is the same). As a result, both expansion and compression occur in the first strain gauge 369a8, and the resistance value of the first strain gauge 369a8 does not change. The same applies to the second strain gauge 369b8. Therefore, the output A of the first detection circuit 373a8 is zero. Similarly, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, both the first strain gauge 369a8 and the second strain gauge 369b8 are both expanded and compressed, and the resistance value does not change. Therefore, the output A of the first detection circuit 373a8 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a8 and the second strain gauge 369b8 are expanded, the resistance value of both increases. Therefore, the output A of the first detection circuit 373a8 is zero. In addition, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a8 and the second strain gauge 369b8 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a8 is zero.

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R extends, both the first strain gauge 369a8 and the second strain gauge 369b8 are compressed, so that the resistance value of both decreases. Therefore, the output A of the first detection circuit 373a8 is zero. Further, when the right crank 105R is compressed, both the first strain gauge 369a8 and the second strain gauge 369b8 are expanded, so that the resistance value of both increases. Therefore, the output A of the first detection circuit 373a8 is zero.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the first strain gauge 369a8 is expanded and the resistance value is increased, and the second strain gauge 369b8 is compressed and the resistance value is decreased. Therefore, the output A of the first detection circuit 373a8 is a positive output (the potential Vab is high and the potential Vr is low). When the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the resistance value decreases because the first strain gauge 369a8 is compressed, and the resistance value increases because the second strain gauge 369b8 is expanded. To do. Therefore, the output A of the first detection circuit 373a8 is a negative output (the potential Vab is low and the potential Vr is high).

  As described above, only the torsional deformation rz is detected from the A output. In other words, the first detection circuit 373a8 is connected to the first strain gauge 369a8 and the second strain gauge 369b8, and detects the strain in the twist direction generated in the crank 105.

  Next, how each deformation is detected (measured) in the B output of the second detection circuit 373b8 will be described. In the bending deformation x, the right crank 105R is deformed from the upper surface 117 toward the lower surface 118 or in the opposite direction. When the right crank 105R is deformed from the upper surface 117 toward the lower surface 118, both the first strain gauge 369a8 and the second strain gauge 369b8 are both internally expanded and compressed, and the resistance value does not change. Therefore, since the potential V1 does not change, the B output of the second detection circuit 373b8 is zero. Similarly, when the right crank 105R is deformed from the lower surface 118 toward the upper surface 117, both the first strain gauge 369a8 and the second strain gauge 369b8 are both expanded and compressed and the resistance value does not change. Therefore, since the potential V1 does not change, the B output of the second detection circuit 373b8 is zero.

  In the bending deformation y, the right crank 105R is deformed from the outer surface 120 toward the inner surface 119 or in the opposite direction. When the right crank 105R is deformed from the outer surface 120 toward the inner surface 119, since both the first strain gauge 369a8 and the second strain gauge 369b8 are expanded, the resistance value of both increases. Therefore, the output B of the second detection circuit 373b8 is a positive output (the potential V1 is high and the potential V2 is low). In addition, when the right crank 105R is deformed from the inner surface 119 toward the outer surface 120, both the first strain gauge 369a8 and the second strain gauge 369b8 are compressed, so that the resistance value of both decreases. Therefore, the output B of the second detection circuit 373b8 is a negative output (the potential V1 is low and the potential V2 is high).

  The tensile deformation z is deformed so that the right crank 105R is stretched or compressed in the longitudinal direction. When the right crank 105R extends, both the first strain gauge 369a8 and the second strain gauge 369b8 are compressed, so that the resistance value of both decreases. Therefore, the B output of the second detection circuit 373b8 is a negative output. Further, when the right crank 105R is compressed, both the first strain gauge 369a8 and the second strain gauge 369b8 are expanded, so that the resistance value of both increases. Therefore, the B output of the second detection circuit 373b8 is a positive output.

  The torsional deformation rz deforms so that the right crank 105R is twisted. When the right crank 105R is twisted in the direction of the arrow in FIG. 6B, the first strain gauge 369a8 is expanded and the resistance value is increased, and the second strain gauge 369b8 is compressed and the resistance value is decreased. Therefore, the B output of the second detection circuit 373b8 is zero. When the right crank 105R is twisted in the direction opposite to the arrow in FIG. 6B, the resistance value decreases because the first strain gauge 369a8 is compressed, and the resistance value increases because the second strain gauge 369b8 is expanded. To do. Therefore, the B output of the second detection circuit 373b8 is zero.

  As described above, the bending deformation y and the tensile deformation z are detected from the B output. That is, the second detection circuit 373b8 is connected to the first detection circuit 373a8 and the constant current power source 3748, and detects the internal / external strain or tensile strain generated in the crank 105.

From the A output of the first detection circuit 373a8 and the B output of the second detection circuit 373b8, the propulsive force Ft and the loss force Fr are the same as the expression (1) and the fourth embodiment shown in the first embodiment. Each is calculated by the equation (8) shown. The tensile deformation z is very small compared to the bending deformation y and can be ignored. The expressions (1) and (8) are shown again below.
Ft = p (A−A0) + q (B−B0) [kgf] (1)
Fr = s (A−A0) + u (B−B0) [kgf] (8)

Here, p, q, s, and u are coefficients, which are values calculated by simultaneous equations composed of the equations (3) to (6) shown in the first embodiment. The expressions (3) to (6) are shown again below.
m = p (Am−A0) + q (Be−B0) (3)
0 = s (Am−A0) + u (Be−B0) (4)
0 = p (Ae−A0) + q (Bm−B0) (5)
m = s (Ae−A0) + u (Bm−B0) (6)

  The coefficients p, q, s, u, and A0 and B0 are values that can be calculated or measured in advance. It can be calculated.

  In the equation (1), the A output is corrected using the B output. In equation (8), the A output is used to correct the B output. That is, the measurement module control unit 351 that calculates each formula functions as a correction unit. Thereby, the influence of distortion other than the detection target contained in the 1st detection circuit 373a8 or the 2nd detection circuit 373b8 can be excluded. If the first strain gauge 369a8 and the second strain gauge 369b8 are not displaced in the crank direction (direction parallel to the central axis C1), Ae = A0 and correction by the B output is not necessary. In the present embodiment, Be = B0 is always satisfied, so that correction by the A output is not necessary.

  The propulsive force Ft and the loss force Fr calculated in this way are transmitted to the cycle computer 201 as in the first embodiment. The operations in the measurement module control unit 351 and the operations of the cycle computer 201 and the cadence sensor 501 are the same as those in the flowcharts shown in FIGS.

  According to the present embodiment, the measurement module 301 includes a first strain gauge 369a8 and a second strain gauge 369b8 provided on the inner surface 119 of the crank 105 of the bicycle 1, and a first strain gauge 369a8 and a second strain gauge 369b8. A first deformation circuit 373a8 for detecting torsional deformation rz generated in the crank 105, to which a current power supply 3748 is connected, a first detection circuit 373a8, and a constant current power supply 3748 are connected, and bending deformation y generated in the crank 105 And a second detection circuit 373b8 for detecting the tensile deformation z. The detection directions of the first strain gauge 369a8 and the second strain gauge 369b8 are orthogonal to each other, and the intermediate direction of the detection direction of the first strain gauge 369a8 and the second strain gauge 369b8 is the longitudinal direction of the crank 105. Is provided. Thus, the propulsive force Ft and the loss force applied to the crank 105 from the torsional deformation rz detected by the first detection circuit 373a8 and the bending deformation y and the tensile deformation z detected by the second detection circuit 373b8. Fr can be measured. Therefore, the propulsive force Ft and the loss force Fr can be measured by a simple method. In addition, since the constant current power source 3748 is used, the number of strain gauge elements can be reduced. Further, since the first strain gauge 369a8 and the second strain gauge 369b8 are provided only on the inner surface 119 of the crank 105, the propulsive force Ft and the loss force Fr can be measured with only one surface, and the inner surface 119. By providing in, it does not interfere with the user's foot.

  Further, the first detection circuit 373a8 and the second detection circuit 373b8 are configured by a bridge circuit, and the first strain gauge and the second strain gauge are serially connected to the constant current power source 3748 in the bridge circuit configuring the first detection circuit 373a8. In addition, a resistance element other than the first strain gauge 369a8 and the second strain gauge 369b8 of the bridge circuit constituting the first detection circuit 373a8 and the bridge circuit constituting the second detection circuit 373b8 is connected to Since it is configured by the resistor R1 and the fixed resistor R2, the bending deformation x, the bending deformation y, and the tensile deformation z can be detected by the bridge circuit, and the propulsive force Ft and the loss force Fr are measured with a simple circuit configuration. be able to.

  In addition, since the first strain gauge 369a8 and the second strain gauge 369b8 are overlapped with each other, the size of the strain gauge 369 can be reduced.

  Note that the first strain gauge 369a8 and the second strain gauge 369b8 may be arranged individually without overlapping.

  In the first detection circuit 373a8, the connection order of the first strain gauge 369a8 and the second strain gauge 369b8 may be reversed.

  In the eight embodiments described above, the cycle computer 201 displays the average propulsive force and the average loss force per second, but for example, the average propulsive force for each rotation angle of the crank 105 (30 °, etc.) The average loss force may be calculated and the magnitude thereof may be displayed with an arrow or the like. The rotation angle of the crank 105 is composed of, for example, an optical rotation detection sensor having a light emitting part and a light receiving part, which is confined in the vicinity of the outer periphery of the crank gear, and a gear passing between the light emitting part and the light receiving part. There are a method of detecting the rotation angle, a method of detecting with an existing sensor such as a potentiometer, and the like by counting the number of teeth and obtaining a ratio between the count value and the number of teeth of the gear.

  Further, the transmission efficiency for each rotation angle of the crank 105 may be calculated from the calculated propulsive force Ft and the loss force Fr and displayed. The transmission efficiency is a contribution ratio of the propulsive force Ft to the force acting on the pedal 103 and is an index indicating the pedaling state. Further, a predetermined threshold value may be set for the transmission efficiency, and if it is equal to or less than the threshold value, it may be determined that the pedaling state is poor and inefficient, and the result is displayed as a graphic or the like.

  In the eight embodiments described above, the strain gauge 369 is provided on the right crank 105R, but it can also be provided on the left crank 105L. As a result, the user can know the left and right pedaling balance.

  Further, the strain gauge 369 may be embedded in the crank 105 during the manufacturing process of the crank 105. When the crank 105 has a hollow structure, the strain gauge 369 may be bonded to the inside of the hollow. According to these methods, the strain gauge 369 can be disposed without deteriorating the appearance of the crank 105. Further, since the strain gauge 369 is not exposed to the outside, durability of the strain gauge 369 can be improved.

  4 and the like, the strain gauge 369 is described as being provided near the center of the crank 105, but may be provided near the pedal 103 or the crankshaft 107. When provided near the pedal 103, the strain of the crank 105 is small, so that the life of the strain gauge 369 can be extended. If it is provided near the crankshaft 107, the output of the strain gauge 369 is increased by this principle, and the influence of noise can be reduced.

  Further, although the strain gauge 369 is provided on the inner surface 119 of the crank 105, it may be provided on the outer surface 120. However, when provided on the outer surface 120, there is a possibility of buffering with the user's foot.

  Further, the strain gauge 369 is not limited to being composed of one element, but may be composed of a plurality of elements. The resistance values of the strain gauges 369 are not limited to the same, but the strain gauges 369 and the fixed resistance R must have resistance values that have a relationship of outputting a positive output or a negative output when each deformation is detected. Don't be.

  The human-powered machine according to the present invention refers to a machine driven by human power provided with a crank 105 such as a bicycle 1 or a fitness bike. In other words, any human-powered machine may be used as long as it is a machine that is driven by a human power equipped with the crank 105 (it is not always necessary to move locally).

  The measuring device in the present invention may be a part of the cycle computer 201 or may be another independent device. Further, it may be an aggregate of a plurality of devices physically separated. In some cases, a device other than the strain gauge 369 (measurement module strain detection circuit 365) may be a device in a completely different place through communication. That is, the measurement module 301 is an example of a measurement apparatus according to the present invention.

  Further, the present invention is not limited to the above embodiment. That is, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the scope of the present invention. Of course, such modifications are included in the scope of the present invention as long as the configuration of the measuring apparatus of the present invention is provided.

1 Bicycle (human-powered machine)
105 Crank 119 Inner surface (side surface)
120 External surface (side surface)
369a 1st strain gauge 369b 2nd strain gauge 369c 3rd strain gauge 369d 4th strain gauge 369e 5th strain gauge 369f 6th strain gauge 369g 7th strain gauge 369h 8th strain gauge 373a 1st detection circuit 373b 2nd detection circuit 373c 1st detection circuit 373d 2nd detection circuit C1 Center axis R Fixed resistance ST11 A / D conversion by measurement module A / D (rotational direction strain detection process, internal / external strain or tensile direction strain detection process)
ST33 Average propulsive force, average loss force calculation (propulsion force measurement process, loss force measurement process)

Claims (10)

A first detection circuit that detects a rotational direction strain generated in a direction in which a crank of a human-powered machine rotates;
A second detection circuit for detecting another direction strain generated in a direction different from the direction of rotation of the crank;
A control unit that measures a propulsive force of the manpower machine based on a detection result of the first detection circuit and measures a loss force of the manpower machine based on the detection result of the second detection circuit. A measuring device.   The second detection circuit may be a strain in an inward / outward direction generated in a direction perpendicular to a plane including a circle defined by the rotational movement of the crank, or a direction parallel to a longitudinal direction of the crank as the separate direction strain. The measuring apparatus according to claim 1, wherein at least one of the generated strains in the tensile direction is detected. A first strain gauge, a second strain gauge, a third strain gauge and a fourth strain gauge provided on a side surface which is a surface of the crank parallel to the plane;
The first detection circuit is connected to the first strain gauge and the second strain gauge,
The second detection circuit is connected to the third strain gauge and the fourth strain gauge,
The first strain gauge to the third strain gauge are provided so that a detection direction is parallel to a longitudinal direction of the crank,
The fourth strain gauge is provided so that the detection direction is perpendicular to the longitudinal direction of the crank.
The measuring apparatus according to claim 1 or 2, wherein   It has a correction means for correcting a distortion component mixed in other than the distortion detected by each detection circuit based on the output of the first detection circuit and the output of the second detection circuit. The measuring apparatus according to claim 1.   5. The measuring apparatus according to claim 3, wherein the first strain gauge and the second strain gauge are provided so as to be symmetric with respect to a longitudinal central axis of the crank side surface.   The measurement apparatus according to claim 3, wherein the third strain gauge and the fourth strain gauge are overlapped with each other. The first detection circuit and the second detection circuit are configured by a bridge circuit,
The first strain gauge and the second strain gauge are connected in series to a power source in the bridge circuit constituting the first detection circuit,
The third strain gauge and the fourth strain gauge are connected in series to a power source in the bridge circuit constituting the second detection circuit;
A resistance element other than the first to fourth strain gauges of the bridge circuit constituting the first detection circuit and the bridge circuit constituting the second detection circuit is constituted by a fixed resistor,
The measuring apparatus according to any one of claims 3 to 6, wherein   The measurement apparatus according to claim 7, wherein the fixed resistor is shared by the first detection circuit and the second detection circuit. A first strain gauge, a second strain gauge, a third strain gauge, a fourth strain gauge, a fifth strain gauge, a sixth strain gauge, and a seventh strain gauge provided on a side surface that is a surface of the crank parallel to the plane. , Further comprising an eighth strain gauge,
The first detection circuit is connected to the first strain gauge, the second strain gauge, the fifth strain gauge, and the sixth strain gauge,
The second detection circuit is connected to the third strain gauge, the fourth strain gauge, the seventh strain gauge, and the eighth strain gauge,
The first strain gauge, the second strain gauge, the third strain gauge, and the eighth strain gauge are provided so that a detection direction is parallel to a longitudinal direction of the crank,
The fourth strain gauge, the fifth strain gauge, the sixth strain gauge, and the seventh strain gauge are provided so that the detection direction is perpendicular to the longitudinal direction of the crank.
The measuring apparatus according to claim 1 or 2, wherein The first detection circuit and the second detection circuit are configured by a bridge circuit,
The first strain gauge, the sixth strain gauge, the second strain gauge, and the fifth strain gauge are respectively connected to diagonal positions in the bridge circuit constituting the first detection circuit;
The third strain gauge, the eighth strain gauge, the fourth strain gauge, and the seventh strain gauge are connected to diagonal positions in the bridge circuit constituting the second detection circuit, respectively.
The measuring apparatus according to claim 9.

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