JPH11189193A - Bicycle equipped with motor driven auxiliary power unit - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a low-priced torque detecting mechanism for a bicycle equipped with a motor driven auxiliary power unit. SOLUTION: Determination is made by a saturation determining means 203 as to whether a detected torque value detected by a torque detecting mechanism (torque sensor 100, or the like) for detecting depressing torque according to the elongation/contraction amount of a spring elongated/contracted based on a pedal depressing force during running is equal to a saturation value or higher, and if the value is lower than the saturation value, based on the detected torque value, or if the value is equal to the saturation value or higher, based on an estimated maximum torque value calculated by an estimated maximum torque value calculating means 206, an estimated current torque value is calculated by an estimated current torque value calculating means 207. Then, based on the calculated estimated current torque value, a motor output value is calculated by a motor output deciding means 208, a motor 40 is controlled to reach this motor output value, and the spring constant of a spring is reduced. Thus, a low-priced torque detecting mechanism is provided for a bicycle equipped with a motor driven auxiliary power unit.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bicycle with an electric auxiliary power device that travels with the assistance of power from an electric auxiliary power device during manual driving.

[0002]

2. Description of the Related Art An electric auxiliary power unit including a motor and a speed reduction mechanism is provided on a bicycle, and power is supplied from the electric auxiliary power unit during traveling on an uphill or the like to enable easy driving. Bicycles with equipment are widely known.
A method of assisting power during traveling is based on a displacement member that operates according to the amount of expansion and contraction of a spring and that is displaced in accordance with a pedal depression torque (hereinafter also referred to as a stepping force) and a displacement amount of the displacement member. A torque detecting mechanism that operates and detects a torque corresponding to the magnitude of the pedaling force and outputs the torque, and operates according to the amount of deviation of the deviation member to detect the magnitude of the stepping torque. The output of the electric motor is controlled to increase or decrease according to the magnitude of the detected torque value detected by the torque detection mechanism. It is what you are doing.

[0003] The deflection mechanism in the torque detecting mechanism is a fixed member made of, for example, a drive gear that is integrally rotated with one end of a hollow shaft provided on a hanger lug of the vehicle body and is restricted from moving in the axial direction. And a drive plate which is attached with a crank having a pedal at both ends and which is depressed by a pedal to move relative to the fixed member in the rotational direction and to move in the axial direction of the crankshaft in accordance with the movement in the rotational direction. A spring provided between the driving plate and the fixing member and compressed as the driving plate relatively moves with respect to the fixing member; and an axial movement of the driving plate, i.e., an axial direction with respect to the fixing portion. A deflection member that moves in the axial direction of the crankshaft according to the approaching / separating movement. When the pedal is depressed, the drive plate moves in the rotation direction while compressing the spring, and the relative movement amount in the rotation direction increases, and the displacement plate moves in the axial direction with the relative movement. The deviation is applied to a torque detecting means, that is, an operating rod of a torque sensor, and a torque value corresponding to the pedaling force is output based on a movement amount of the operating rod, and an output value of the electric motor is determined based on the detected torque value. The motor is controlled so as to output an output value to assist power.

That is, the pedaling force of the pedal is transmitted to the driving plate, and the spring is compressed against the spring force in accordance with the magnitude of the pedaling force to cause relative movement in the rotational direction and the axial direction with respect to the fixed member. Thus, the displacement member is moved in the axial direction, and the displacement amount of the displacement member is detected by the torque detecting means as a torque value corresponding to the pedaling force. Then, the pedal force of the pedal is converted into the amount of deviation of the deviation member,
This is due to the action of the spring which expands and contracts in the rotation direction with the movement of the drive plate in the rotation direction.

Incidentally, the position where the spring of the torque detecting mechanism is disposed, that is, the distance from the axis of the crankshaft to the position where the spring is disposed is approximately a quarter of the length of the crank. It is. Therefore, the magnitude of the load applied to the spring, that is, the magnitude of the compression force is approximately four times the pedaling force of the pedal. On the other hand, the magnitude of the pedaling force applied to the pedal, when traveling on a steep uphill,
Since the weight exceeds approximately 50 kg weight (kilogram weight), a force having a magnitude exceeding 200 kg weight is applied to the spring. It is desirable that the compression length of the spring when the pedal is depressed is as small as possible. The reason is that if the compression length is too large, the driver will play in the depressing direction when depressing the pedal, so the driver will not feel the depression of the pedal and will feel uncomfortable and the riding comfort will be poor. Will occur.

Therefore, according to experiments by the inventor, it is desirable that the rotation angle of the crank at which the maximum compression is obtained be within about 10 degrees, and the compression length of the spring at this time is 3 mm (millimeter).
It was confirmed that the following was desirable. The length of the spring, that is, the free length is about 15 to 20 mm.

Therefore, there is a problem that a spring having a large spring constant that satisfies the above conditions is difficult to manufacture and expensive.

[0008]

As described above, there is a problem that the spring constituting the conventional torque detecting mechanism, that is, the spring used therein is difficult to manufacture and expensive.

[0009]

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and an invention according to a first aspect of the present invention provides a bicycle with an electric auxiliary power device which travels with power assist from an electric motor. A torque detecting mechanism comprising: a displacement mechanism which operates according to the amount and is displaced in accordance with the pedaling stepping torque; and a torque detecting means for converting the stepping torque value into a voltage signal and outputting the voltage signal in accordance with the amount of displacement of the displacement mechanism. Detecting means for detecting that a torque value is first detected by the torque detecting mechanism and outputting a detection signal; and determining whether a detected torque value from the torque detecting mechanism is equal to or greater than a saturation value. A timing signal when the detected torque value is equal to or greater than the saturation value, a saturation determination unit that outputs the detected torque value when the detected torque value is less than the saturation value, and a time measurement is started based on the detection signal of the detection unit. A time measuring means for measuring a time until a time measuring signal from the saturation determining means and outputting the time measured; a vehicle speed detecting means for detecting a vehicle speed; and the torque detecting mechanism detecting the torque based on the vehicle speed detected by the vehicle speed detecting means. Cycle calculating means for calculating a cycle of the torque signal to be performed; assumed maximum torque value calculating means for calculating an assumed maximum torque value based on a cycle from the cycle calculating means and a time measured from the time measuring means; An assumed current torque value calculation means for calculating an assumed current torque value based on the assumed maximum torque value from the maximum torque value calculation means; and an assumed current torque value from the assumed current torque value calculation means or a detected torque from the saturation determination means. A motor output determining means for determining an output value of the motor based on one of the values; and It is obtained by an electric auxiliary power unit Bicycles and control means for controlling the motive.

According to the first aspect of the present invention, it is determined whether or not the detected torque value detected by the torque detecting mechanism is equal to or greater than a saturation value in accordance with the pedaling force of the pedal. The motor is controlled by the output value of the motor determined based on the detected torque value, and when the torque value is equal to or higher than the saturation value, the detected torque value exceeds the saturation value after the torque value is first detected by the torque detection mechanism. The estimated maximum torque value is calculated from the time counted up to the time when the detected torque value reaches the saturation value and the period of the torque signal detected by the vehicle speed detection means at the time when the detected torque value reaches the saturation value and calculated based on the vehicle speed. Calculate the current assumed torque value based on the torque value,
Since the motor is controlled by the output value of the motor determined based on the current assumed torque value, even if a greater pedal force is applied to the spring after the spring of the torque detection mechanism is compressed to the maximum, The output from the torque detection mechanism in a state where the spring is in the maximum compression state is determined to have reached the saturation value, and the current estimated torque value is determined from the time measured by the time measurement means and the vehicle speed detected by the vehicle speed detection means. , The motor output value is determined and the motor is controlled to assist the power, so that a spring having a small spring constant can be used and the cost can be reduced.

According to a second aspect of the present invention, in the first aspect of the present invention, storage means for setting a predetermined value is provided, and the predetermined value and an assumed current torque value from the assumed current torque value calculating means are stored. And a bicycle with an electric auxiliary power unit that outputs the predetermined value to the electric motor output determining means in place of the assumed current torque value when the assumed current torque value is equal to or greater than the predetermined value.

Thus, the invention according to claim 2 is characterized in that, in the invention according to claim 1, storage means for setting a predetermined value is provided, and the predetermined current value and the estimated current torque value from the assumed current torque value calculation means are provided. Wherein when the assumed current torque value is equal to or greater than the predetermined value, the predetermined value is output to the motor output determining means instead of the assumed current torque value. In addition, even if the assumed current torque value becomes abnormally large due to driving of a driver with strong leg strength or heavy weight, the output of the motor is determined based on the predetermined value instead of the assumed current torque value, based on the predetermined value. Is controlled, and power can be assisted, so that an abnormally large power can be prevented from being assisted.

According to a third aspect of the present invention, in the first or second aspect of the invention, the assumed current torque value is calculated by the assumed current torque value calculating means using a torque signal cycle based on the current vehicle speed. It is a bicycle with an electric auxiliary power unit calculated by the above.

According to the third aspect of the present invention, in the first or second aspect of the present invention, the calculation of the assumed current torque value by the assumed current torque value calculating means is based on the torque signal cycle based on the current vehicle speed. If the vehicle speed changes during running, the bicycle is currently assumed based on the torque signal cycle calculated based on the changed current vehicle speed and the assumed maximum torque value. Since the torque value can be calculated and the electric motor can be controlled so that the electric motor output value is determined based on the current assumed torque value, even if the vehicle speed changes during traveling, appropriate power assist can be performed according to the change in the vehicle speed. It has the effect of being able to do.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of the present invention will be described with reference to FIGS. As shown in FIG. 1, a bicycle A with an electric auxiliary power device (hereinafter simply referred to as a bicycle) A includes a vehicle body B and an auxiliary power device (hereinafter simply referred to as a power device) C attached to the vehicle body B. The vehicle body B includes a standing pipe 2 and a lower pipe 3 having one end fixed to a hanger lug 1, a head pipe 4 fixed to the other end of the lower pipe 3, and one end fixed to the other end. A frame 6 comprising an upper pipe 5 fixed to a lower portion of the standing pipe 2; a chain stay 7 having one end fixed to the hanger lug 1; a front fork 8 attached to the head pipe 4; , A front wheel 10 attached to the lower end of the front fork 8, one end is fixed to the upper part of the standing pipe 2 and the other end is not shown as the other end of the chain stay 7. Backhawk 1 fixed via rear pawl
1, a rear wheel 12 attached to the other end of the chain stay 7, a saddle 13 attached above the standing pipe 2, a load receiving stand 14 provided above the rear wheel 12, and the like.

The hanger lug 1 is provided with a crankshaft 80 described later so as to be rotatable.
A left crank 81 and a right crank 82 provided with pedals 81a and 82a, respectively, are attached to both ends. A storage battery case 14a containing a storage battery 14b as a power supply is mounted on the upper part of the receiving table 14. The storage battery 14b is supplied with electric power via a lead 16 to a motor 40 and the like described later. In addition, a sprocket 1 for transmitting rotational force during traveling.
7 and a sprocket (not shown) of the rear wheel 12
8 are bridged.

Next, the structure of the power unit C will be described with reference to FIGS. As shown in FIG.
Is a case 2 composed of a case body 23 and a lid case 25.
0, the electric motor 40 attached to the case 20;
The case 20 is constituted by a speed reduction mechanism 50.
Is provided with a hollow shaft 70 which is mounted via a bearing and to which rotational force is transmitted from the speed reduction mechanism 50, and a crankshaft 80 penetrating through the hollow shaft 70. In the case 20, a microcomputer, a ROM,
The control device 200 including a RAM and the like is housed.

The case 20 includes a speed reduction mechanism 5.
0 and the control device 200 are stored. The reduction mechanism 50 includes a gear 51 attached to a tip end of an output shaft 41 of the electric motor 40, a large-diameter gear 52 meshed with the gear 51, a small-diameter gear 53 provided integrally with the gear 52, A gear 54 composed of a large-diameter gear 54b and a bevel gear 54c meshing with the gear 53, a bevel gear 55 meshing with the bevel gear 54c, and a shaft 55a mounted on the same shaft as the shaft on which the bevel gear 55 is mounted. The gear 55b includes a drive gear 56 that meshes with the gear 55b.

The gear 55b is mounted on the shaft 55a via a one-way clutch 55f.
The one-way clutch 55f rotates the gear 55b so as to transmit the torque of the electric motor 40 to the drive gear 56 so that the bicycle travels normally, that is, travels in the forward direction, but idles in the opposite direction. It works like that. In other words, the one-way clutch 55f functions so as to idle when the cranks 81, 82 to which the pedals 81a, 82a are attached rotate in the traveling direction during manual driving described below.

A shaft hole 56a is formed at the center of the drive gear 56, and the shaft hole 56a
2c are formed on the side surface of the drive gear 56 on the side of the lid case 25 and concentrically arranged on the outer periphery of the shaft hole 56a as shown in FIGS. 2 and 3 (three in the embodiment, FIG. 2). And only one projection 57 is formed in FIG. 3), and the projection 57 extends upward in the direction of the arrow shown in FIG. 4, that is, in the direction in which the driving gear 56 rotates during traveling as shown in FIG. The inclined surface 57a which gradually rises toward is formed. On the side surface of the drive gear 56 on the side of the lid case 25, as shown in FIG. 3, a plurality (3 in this embodiment) disposed concentrically with the shaft hole 56a between the adjacent protrusions 57. An L-shaped regulating member 58 for regulating one end side of a compression spring 60 as a spring described later (only one is shown in FIGS. 2 and 3) is formed.

The hollow shaft 70 for transmitting the power of the electric motor 40, that is, the rotational force, transmitted through the reduction mechanism 50 to the sprocket 17, is fitted into the shaft hole 56a formed in the drive gear 56. The hollow shaft 70 is rotatably provided on the hanger lug 1 and has a through hole 7 therein.
1 and at one end thereof, a concave / convex ridge 72 is formed to engage with the concave / convex ridge 56c formed in the shaft hole 56a. The shaft 70 is prevented from rotating in the direction, so that the hollow shaft 70 rotates integrally with the drive gear 56. Also,
A mounting member 17a to which the sprocket 17 is mounted is mounted on the other end of the hollow shaft 70.
The hollow shaft 70 is press-fitted into the inner race of the ball bearing 77 in the vicinity of the area where the concave and convex strips 72 are formed. Is attached to the case body 23.

A crankshaft 80 is rotatably provided through the through hole 71 of the hollow shaft 70, and mounting portions 83 and 84 are formed at both ends of the crankshaft 80, respectively.

A one-way clutch 85 is attached to the crankshaft 80 at a position close to the drive gear 56 attached to the hollow shaft 70, and is connected to the crankshaft 80 via the one-way clutch 85. Has a drive plate 90 attached. The one-way clutch 85
Are the pedals 81a, 82 when the crankshaft 80 is running manually.
In the case where the drive plate 90 is rotated in the traveling direction by the left and right cranks 81 and 82 to which the a is attached, the drive plate 90 is rotated. It works like that. A disc-shaped flange portion 91 is formed on the cover case 25 side of the drive plate 90 at a predetermined distance so as to form a space between the drive plate 90 and a side surface of the drive gear 56.
A compression portion 92 is formed on the surface of the flange portion 91 on the side of the drive gear 56, as shown in FIG. And
The compression spring 60 is disposed between the L-shaped regulating member 58 and the compression section 92.

The magnitude of the urging force of the compression spring 60 is adjusted so as to be compressed in accordance with the rotational force applied to the drive plate 90 via the crankshaft 80 and the one-way clutch 85 during manual driving. The spring constant is set so as to be in the maximum compression state with a compression force smaller than the compression force due to the maximum pedaling force generated by a normal user. In other words, during manual driving, the crankshaft 80
Relative to the drive gear 56 in accordance with the rotational force of the drive plate 90 that rotates together with the one-way clutch 85 with the rotation of the one-way clutch 85, and is maximally compressed by a pedaling force smaller than the compressive force by the maximum pedaling force generated by a normal user. That is, at least when the maximum pedaling force is applied, the compression spring 60
Is set to a state where no spring action is applied (a state where it is not compressed any more).

The flange portion 91 of the driving plate 90 has
As shown in FIGS. 2 and 4, three through holes 93 (only one is shown in FIGS. 2 and 5) are formed at portions corresponding to the protrusions 57 formed on the side surface of the drive gear 56.

An offset plate 95 made of an annular plate is provided so as to be able to approach and separate from the flange portion 91, and the offset plate 95 is provided with the through holes 9 respectively.
A slide shaft 96 is provided at a position corresponding to 3 and integrally fixed so as to penetrate an end on one end side into the through hole 93. A spherical projection 96a is formed at the other end of the slide shaft 96. The spherical projection 96a is formed on the inclined surface 57a of the projection 57 formed on the drive gear 56.
The coil spring 97 is biased so as to be pressed against the deflection plate 95. That is, the eccentric plate 95 allows the slide shaft 96 fixed to the eccentric plate 95 to pass through the through hole 93 of the flange portion 91 and is urged by the coil spring 97 so that the spherical projection 96a is formed on the inclined surface 57a. In a state where the drive gear 56 and the drive plate 90 are pressed against each other, the drive gear 56 and the drive plate 90 are disposed so as to be movable in the axial direction of the crankshaft 80. When the pedaling force of the pedals 81a and 82a is applied to the crankshaft 80 via the left and right cranks 81 and 82, the rotational force is applied to the drive plate 90 via a one-way clutch 85 attached to the crankshaft 80. The transmitted drive plate 90 rotates, and when the vehicle is in an accelerated state such as traveling on an uphill during traveling, the pedals 81a and 82a are depressed more strongly than before.
Relative movement according to the treading force between a drive plate 90 attached via a one-way clutch 85 to a crankshaft 80 rotated by a treading force of 1a, 82a and a driving gear 56 rotating integrally with the hollow shaft 70. Will occur. That is, to accelerate the bicycle A, the pedals 81a and 82a are strongly depressed to increase the stepping force, so that the drive plate 90
The compression spring 60 provided between the drive gear 56 and the drive gear 56 is compressed, and the drive plate 90 rotates ahead of the drive gear 56 by an amount corresponding to the pedaling force. Spherical projection 96a of the slide shaft 96
Moves upward along the inclined surface 57a of the projection 57 provided on the drive gear 56, and along with this movement, the coil spring 97 is compressed, and the deflection plate 95 moves in a direction away from the drive gear 56, that is, the deflection plate 95 moves. Will be ranked.

The deflection plate 95 is connected to the drive gear 56.
When the deflection plate 95 is displaced in a direction away from the
The operating rod 140 of the torque sensor 100 as a torque detecting means described later operates in accordance with the amount of deviation of the torque sensor 100, and the torque sensor 100 outputs an electric output according to the pedaling force. (Analog / digital value) The analog value is converted into a digital value by the converter, that is, A / D converted and sent to the control device 200.

The drive gear 56, the compression spring 60,
The drive plate 90, the eccentric play 95, the slide shaft 96, the torque sensor 100, and the spring 97 attached to the one-way clutch 85 constitute a torque detecting mechanism. Also, the inclined surface 57 of the drive gear 56
a, the drive plate 90, the slide shaft 96, and the spring 97 constitute a deflection mechanism.

A start switch 15 is provided on the lid case 25 of the power unit C as shown in FIG.
The start switch 15 is provided with a key insertion hole 15a, and a key (not shown) is inserted into the key insertion hole 15a to perform a closing / opening operation.
The electric power is supplied to and stopped from the electric motor 40 and the like. When the start switch 15 is closed, the vehicle can travel easily with the assistance of the rotational force from the power unit C. When the start switch 15 is opened, the vehicle travels manually using only human power.

Next, the structure of the torque sensor 100 will be described with reference to FIGS. As shown in FIG. 5, the torque sensor 100 includes a case main body 101 including a lower case 110 and an upper case 120 attached to the lower case 110, a strain gauge 130 as a sensor disposed in the case main body 101, An operating rod 140 which receives the pedal force of the pedal which is the detected torque, that is, the operating force of the rotational torque of the crankshaft 80, and the operating rod 140
And a coil spring 150 for transmitting the acting force received to the strain gauge 130.

The upper case 120 has a bottom wall 1.
21 is formed with a cylindrical portion 125 protruding inward and outward, respectively. The cylindrical portion 125 is formed with a guide hole 126 at a portion from the outer end portion to a substantially intermediate portion, and is formed from the intermediate portion to the inner side. Guide hole 1 at the end
A hole 127 larger in diameter than 26 is formed.

Then, the sensor, that is, the strain gauge 1
Reference numeral 30 denotes four thin-film resistors R1 formed on a surface of a strain body 131 made of, for example, aluminum through an insulating film.
To R4 (not shown in FIG. 5) by sticking or so-called semiconductor technology, and these four resistors R1 to R4 are connected by conductors to form a bridge W as shown in FIG. It is configured.
The connection point between the resistors R1 and R3 and the connection point between the resistors R4 and R2 of the bridge W are connected to the lead wire 132a.
And 132b are connected to a power supply, and the connection point between the resistors R1 and R4 and the connection point between the resistors R2 and R3 are output ends. A corresponding electrical output is output, and the electrical output is sent to the control device 200 via the A / D converter 110 through the leads 133a and 133b.

The free end 131a of the flexure element 131 fixed to the lower case 110 and the upper case 120 with the fixed end sandwiched therebetween is located below the inner end of the cylindrical portion 125 and has a guide hole 126. A pin 134 having an axis coinciding with the axis of the guide hole 126 is attached to the distal end portion.
Also, the operating rod 140 is guided by the guide hole 126 and is fitted slidably in the axial direction,
A large diameter stopper portion 142 is formed at one end of the shaft portion 141 and has a steel ball 142a rotatably fitted to reduce friction.
Between the coil spring 150 and the pin 134
Are arranged in a state compressed by a predetermined amount.

The operation of the torque sensor 100 is based on the same principle as that of a conventionally known torque sensor using a strain gauge. That is, Pedal 81a, 8
The pedaling force 2a is transmitted to the crankshaft 80, and a bending force corresponding to the amount of deflection of the deflection plate 95 that changes according to the magnitude of the rotational force of the crankshaft 80 is applied to the flexure element 131. The bridge W outputs an electrical output corresponding to a change in the resistance value of the resistors R1 to R4. In this embodiment, the maximum bending force is applied to the strain body 131 when the deflection plate 95 is not deflected.

As shown in FIG. 3, a speed sensor 160 as a vehicle speed detecting means for detecting the speed of the bicycle A is provided inside the case 20, and a known magnetic sensor is used as the speed sensor 160. And
A detection unit (not shown) of the speed sensor 160 is disposed close to the teeth of the drive gear 56, and is generated each time each tooth of the drive gear 56 approaches the detection unit by the rotation of the drive gear 56. The vehicle speed is detected based on the number of pulses per unit time of the pulse signal, and the output is sent to the control device 200.

Next, the rear wheel 1 of the driving force of the electric motor 40 will be described.
2 will be described.

The pedals 81a and 82 are set so that the bicycle A is accelerated as in the case of running on an uphill or the like in manual driving.
a, as described above, the pedals 81a, 82a
The driving force increases to exceed a predetermined value, and the driving plate 90 rotates ahead of the driving gear 56 to cause relative movement of the driving plate 56 and the driving gear 56 by an amount corresponding to the pressing force. Is a protrusion 5 provided on the drive gear 56.
7 is moved upward, and the deflection plate 95 is shifted in a direction away from the driving gear 56 by a deflection amount corresponding to the magnitude of the pedaling force. As a result, the maximum bending force applied to the flexure element 131 via the operating rod 140 and the coil spring 150 decreases, and the flexure element 131 is restored. With this restoration, the resistance values of the resistors R1 to R4 of the bridge W are restored. Is changed, and an electrical output corresponding to the change is sent to the control device 200.

The motor 40 is driven by the control device 200 as described later, and the rotational force of the motor 40 is transmitted from the gear 42 provided on the output shaft 41 to the speed reduction mechanism 50.
And transmitted to the hollow shaft 70 via the drive gear 56, and transmitted to the rear wheel 12 via the sprocket 17 and the chain 18 attached to the hollow shaft 70. is there. That is, Pedal 81
The bicycle runs by adding or assisting the rotational force of the electric motor 40, that is, the power, to the rotational force of the human power transmitted to the crankshaft 80 by stepping on the a and 82a.

Next, the bicycle A according to this embodiment
A control method for assisting the power according to the pedaling force of the vehicle will be described with reference to the control block diagram of FIG.

In the figure, reference numeral 200 denotes the control device described above. Next, the configuration of the control device 200 will be described.

A torque generation detecting means 201 is connected to a torque sensor 100 which is a torque detecting means constituting the torque detecting mechanism. The torque generation detecting means 201 detects the torque by the torque sensor 100 first. That is, it detects that the detected value is not zero. The torque generation detecting means 201 is connected to a time measuring means 202 including a timer.
The timing unit 202 starts timing from the time when the torque generation detecting unit 201 detects the torque.

The torque sensor 100 is connected to a saturation determining means 203, and the saturation determining means 203 is connected to a saturation value storage means 204. The saturation value storage means 204 stores the compression spring 6.
When 0 is the maximum compression state, that is, the state where compression is no longer possible, the same value as the torque value detected by the torque sensor 100, that is, a predetermined value is stored.
In other words, after the compression spring 60 has reached the maximum compression state, even if the pedal is depressed with a greater depression force, the drive plate 9
0 and the drive gear 56 do not move relative to each other in the stepping direction, and the deviation play 95 does not move any further, and the torque value detected by the torque sensor 100 also increases further. Is not constant. This is equivalent to a value in a state where the detected torque value detected by the torque sensor 100 is saturated, that is, a saturated value when viewed from the output side of the torque sensor 100. Therefore, the same value as the detected torque value detected by the torque sensor 100 when the compression spring 60 is in the maximum compression state is stored in the saturation value storage means 204.
Can be considered as the saturation value of Therefore, in the following description, the predetermined value stored in the saturation value storage means 204 will be referred to as a saturation value.

The saturation determination means 203 compares the detected torque value output from the torque sensor 100 during running of the bicycle with the saturation value of the saturation value storage means 204, and the detected torque value is the same as the saturation value. When the detected torque value is larger or larger, that is, when the detected torque value is equal to or more than the saturation value, a time stop signal is output to the time counting means 202. Outputs the value.

When receiving the timing stop signal from the saturation judging means 203, the timing means 202 sets the time from when the torque generation detecting means 201 first detects the torque to when it receives the timing stop signal, that is, The time from when the torque sensor 100 first detects the torque to when the detected torque value is saturated is measured, and the measured time is output.

A cycle calculating means 205 is connected to the speed sensor 160 serving as the vehicle speed detecting means. The cycle calculating means 205 determines the cycle of the current torque signal detected by the torque sensor 100 based on the vehicle speed. Calculate and output this cycle.

The reason why the cycle of the torque signal is obtained from the vehicle speed is that the operation of depressing the pedal of the user during the running is a rotary motion, so that the output of the torque sensor 100, that is, the torque signal becomes sinusoidal. Since there are two left and right cranks, the cycle is halved. Since the rotational speed of the crank is proportional to the vehicle speed, the vehicle speed is detected and the cycle of the torque signal is determined based on the vehicle speed. Can be done.

Next, an assumed maximum torque value calculating means (hereinafter referred to as a maximum value calculating means) 206 is connected to the time measuring means 202 and the period calculating means 205, and the maximum value calculating means 206 The assumed maximum torque value is calculated based on the time measured from 202 and the cycle from the cycle calculating means 205.

The maximum value calculation means 206 includes an assumed current torque value calculation means (hereinafter referred to as current torque value calculation means).
207 is connected, and the current torque value calculating means 2
Reference numeral 07 denotes an assumed current torque value (a torque value assumed to be generated by depressing the current pedal) based on the assumed maximum torque value calculated by the maximum value calculation means 206.

Here, the reason why the assumed maximum torque value is calculated based on the time measured from the time measuring means 202 and the cycle from the cycle calculating means 205, and the assumed current torque value is calculated based on the assumed maximum torque value. The reason will be described below.

As described above, the cycle of the torque signal is obtained from the vehicle speed. On the other hand, the time from when the torque sensor 100 first detects the torque to when it is saturated is measured by the timer 202.

Here, assuming that the cycle of the crank is T, the time from when the torque sensor 100 first detects the torque until saturation is t, and the assumed maximum torque value is A, the output of the torque sensor 100 is as described above. When expressed as a cosine, the output value f (t) of the torque sensor 100 at the time of saturation when the detected torque value of the torque sensor 100 is saturated is expressed by the following equation (1). Desired.

By modifying the equation (1), the assumed maximum torque value A can be obtained by the equation (2).

[0053]

(Equation 1)

Therefore, the time from when the torque sensor 100 first detects the torque measured by the time measuring means 202 to the time when the torque sensor 100 is saturated, the detected torque value when the torque sensor 100 is saturated, and the time calculated by the cycle calculating means 205 The estimated maximum torque value A can be obtained by substituting the calculated cycle into the equation (2), and the maximum value calculating means 206 calculates the assumed maximum torque value by performing the above calculation. is there.

Further, a new time and the assumed maximum torque value are substituted into the equation (1) at predetermined time intervals (designated by a lock pulse signal) after the timing means 202 detects the saturation torque value. The current torque value calculating means 207 calculates the assumed current torque value by performing the above calculation.

When receiving the timing stop signal from the saturation judging means 203, the timing means 202 determines the time from when the torque generation detecting means 201 detects torque to when the torque generation detecting means 201 receives the timing stop signal, that is, the torque sensor. 1
00 measures the time from when the torque is first detected to when the detected torque value is saturated, and outputs this measured time.

The motor output determining means 208 is connected to the current torque calculating means 207, and the saturation determining means 203 is connected to the motor output determining means 208 as described above. The motor output determining means 208 determines the electric motor 4 based on the detected torque output from the saturation determining means 203 when the detected torque detected by the torque sensor 100 is smaller than the saturation value.
The output value of 0, that is, the magnitude of the power to be assisted is determined. When the detected torque value detected by the torque sensor 100 is equal to or larger than the saturation value, the output value is set based on the assumed current torque value from the current torque calculation unit 207. The output value of the electric motor 40 is determined.

A motor control means 209 is connected to the motor output determination means 208. The motor control means 209 outputs the assumed current torque value from the current torque calculation means 207 or the saturation judgment means 203. The motor 40 is controlled based on the output from the motor output determining means 208 determined based on one of the detected torque values.

That is, the electric motor 40 detects that the torque value detected by the torque sensor 100 which is a part of the torque detection mechanism is less than the saturation value (from the torque sensor 100 when the compression of the compression spring 60 is less than the maximum compression). Is detected, the control is performed so as to assist the power corresponding to the detected torque value.
Is greater than or equal to the saturation value (compression spring 6
When 0 becomes the detected torque value of the torque sensor 100 detected in the state of maximum compression), control is performed so as to assist the power corresponding to the output value determined by the assumed current torque value. .

This will be described with reference to FIG. FIG.
, A curve A is a curve indicating a change in the pedal effort, and a curve B is a curve indicating a change in the output of the torque sensor 100, that is, a change in the detected torque value. As shown in the figure, the compression spring 60 is gradually compressed as the pedaling force gradually increases from the time t0, and the detected torque value from the torque sensor 100 also increases with this compression, and the compression spring 6
At time t1 when 0 is in the maximum compression state, the detected torque value is kept constant without further increase, that is, it is saturated. Then, when it becomes saturated, the time measured by the time measuring means 202 (time from time t0 to time t1)
And a period calculating means 20 based on the vehicle speed at time t1.
The estimated current torque value at each time from time t2 to time t (n-1) calculated based on the torque signal cycle calculated in step 5 changes as plotted with squares. From time t0 to time t1, the motor output value is determined by the gradually increasing detected torque value, and from time t2 to time t (n-1), the motor output value is determined by the assumed current torque value. The motor 40 is controlled so that

As described above, when the compression spring 60 is at or above the maximum compression state, the motor output value is determined based on the assumed current torque value and the motor 40 is controlled. It is not necessary to use a spring having a large constant.

In the case where a driver with strong leg strength or a driver with a heavy weight drives, if the driver depresses the pedal so as to accelerate rapidly, the assumed maximum torque value becomes abnormally large. The assumed current torque value becomes abnormally large, and abnormally large power is assisted, which is an undesirable state.

In order to prevent this, as shown in FIG. 9, the assumed current torque value calculated by the current torque calculation means 207 is replaced with a predetermined value stored in the storage means 210 in advance. And a determining means 211 for determining which is greater than the predetermined current torque value when the determining means 211 determines that the assumed current torque value is larger than the predetermined value. The predetermined value is replaced with the motor output determining means 208.
, And the motor output may be determined based on the predetermined value. In FIG. 9, FIG.
The same reference numerals are given to the same parts as.

Since the power is assisted during traveling in an acceleration state, the time when the assumed maximum torque value is calculated and the assumed current torque value calculated based on the assumed maximum torque value are calculated and determined. Motor output value, the vehicle speed after that is greater than the vehicle speed at the time when the assumed maximum torque value was calculated, and the cycle of the torque signal becomes shorter, so that the assisted power corresponding to the actual pedaling force becomes smaller become. In order to prevent this, in the control block diagrams of FIGS. 7 and 9, the torque signal cycle for the calculation by the maximum value calculation unit 206 is stored in the storage unit (not shown), and the current torque value calculation unit is stored. A comparison unit (not shown) compares the cycle of the torque signal at the time of calculating the assumed current torque value with the comparison means (not shown). If there is a difference between the two, the cycle of the torque signal at the time of calculating the assumed current torque value is determined. It is only necessary to calculate the assumed current torque value using the estimated current torque value and determine the motor output based on the assumed current torque value.

As described above, in the bicycle with the electric auxiliary power unit, whether or not the detected torque value detected by the torque sensor 100 which is a part of the torque detection mechanism exceeds the saturation value in accordance with the depression force of the pedals 81a and 82a. If the value is less than the saturation value, the motor 40 is controlled by the motor output value determined based on the detected torque value. From the time until the value reaches or exceeds the saturation value, that is, the time when the saturation value is reached, and the period of the torque signal calculated based on the vehicle speed detected by the speed sensor 160 at the time when the detected torque value reaches the saturation value, the assumed maximum A torque value is calculated, a current assumed torque value is calculated based on the assumed maximum torque value, and the motor output value is determined based on the current assumed torque value. Thus, even if a greater pedal force is applied to the compression spring 60 after the compression spring 60 of the torque detecting mechanism is fully compressed, the torque sensor in the state where the compression spring 60 is fully compressed is controlled. It is determined that the output from the motor 100 has exceeded the saturation value, and the current assumed torque value is determined from the time measured by the time measuring means 202 and the vehicle speed detected by the speed sensor 160 to determine the motor output value. Since the power can be assisted by controlling the electric motor 40 so that the output value is obtained, the compression spring 60 having a small spring constant can be used.

A storage means 210 in which a predetermined value is set is provided, and a judgment means 211 for judging whether the predetermined value or the assumed current torque value from the current torque value calculation means 207 is larger is provided. When the assumed current torque value exceeds the predetermined value, the predetermined value is replaced with the motor output determination means 2 instead of the assumed current torque value.
In this case, even if the assumed current torque value becomes abnormally large in the case of a driver with strong leg strength or a heavy weight driver, the estimated current torque value becomes abnormally large. Since the power can be assisted by determining the motor output value based on the predetermined value and controlling the motor, it is possible to prevent the abnormally large power from being assisted.

Further, by calculating the assumed current torque value by the current torque value calculation means 207 using a torque signal cycle based on the current vehicle speed, when the vehicle speed changes during traveling, this change occurs. Since the motor 40 can be controlled by the motor output value determined based on the assumed current torque value calculated based on the cycle of the torque signal calculated based on the current vehicle speed and the assumed maximum torque value,
Assuming that the vehicle speed changes during traveling, appropriate power assistance can be performed according to the vehicle speed.

[0068]

According to the first aspect of the present invention configured as described above,
It is determined whether or not the detected torque value detected by the torque detection mechanism according to the pedaling force has become equal to or greater than a saturation value, and if less than the saturation value, the output value of the motor determined based on the detected torque value is used. When the motor is controlled and the saturation value is exceeded, the measured time from when the torque detection mechanism first detects the torque value to when the detected torque value exceeds the saturation value, that is, when the detected torque value reaches the saturation value, and when the detected torque value reaches the saturation value Calculate the assumed maximum torque value from the period of the torque signal calculated based on the vehicle speed detected by the vehicle speed detection means at the time when the vehicle reaches the estimated maximum torque value, calculate the current assumed torque value based on the estimated maximum torque value, Since the motor is controlled by the output value of the motor determined based on the current assumed torque value, a greater pedal force is applied after the spring of the torque detection mechanism is compressed to the maximum. Even if it is applied to the spring, the output from the torque detecting mechanism in a state where the spring is compressed to the maximum is determined to be in a state of reaching the saturation value, and the time measured by the time measuring means and the vehicle speed detecting means are detected. Since the current assumed torque value is obtained from the vehicle speed to determine the motor output value and the motor can be controlled to assist the power, a spring having a small spring constant can be used and the cost can be reduced. .

According to a second aspect of the present invention, in the first aspect of the invention, storage means for setting a predetermined value is provided, and the predetermined value and an assumed current torque value from the assumed current torque value calculating means are stored. Wherein the predetermined value is output to the motor output determining means in place of the assumed current torque value when the assumed current torque value exceeds the predetermined value. In addition to the above, even if the assumed current torque value becomes abnormally large due to driving of a driver with strong leg strength or heavy weight, the output of the electric motor is determined based on the predetermined value instead of the assumed current torque value. Since the power can be assisted by controlling the electric motor, it is possible to prevent an abnormally large power from being assisted.

According to a third aspect of the present invention, in the first or second aspect of the present invention, the calculation of the assumed current torque value by the assumed current torque value calculating means is performed by setting a torque signal cycle based on the current vehicle speed. Since the bicycle with the electric auxiliary power unit is calculated by using the present invention, in addition to the effects of the respective inventions according to claim 1 or 2, when the vehicle speed changes during running, based on the changed current vehicle speed, A current assumed torque value is calculated based on the calculated torque signal period and the assumed maximum torque value, and the motor can be controlled to have a motor output value determined based on the current assumed torque value. Even if the vehicle speed changes, there is an effect that appropriate power assist can be performed according to the change in the vehicle speed.

[Brief description of the drawings]

FIG. 1 is an overall view of an embodiment of a bicycle with an electric auxiliary power device according to the present invention.

FIG. 2 is a sectional view showing a configuration of the auxiliary power unit according to the embodiment.

FIG. 3 is a side view showing the auxiliary power unit of the embodiment.

FIG. 4 is a partial view showing the relationship of the operation of the deflection mechanism in the embodiment.

FIG. 5 is a cross-sectional view of the torque detecting means (torque sensor) of the embodiment.

FIG. 6 is a circuit diagram of a torque detecting means (torque sensor) of the embodiment.

FIG. 7 is a control block diagram in the embodiment.

FIG. 8 is a diagram showing the relationship between the pedaling force and changes in detected torque value and assumed current torque value in the embodiment.

FIG. 9 is another control block diagram in the embodiment.

[Explanation of symbols]

A Bicycle with electric auxiliary power unit. B Car body C Auxiliary power unit 40 Electric motor 56 Drive gear (part of torque detection mechanism and deflection mechanism) 60 Compression spring (spring) (part of torque detection mechanism) 80 Crankshaft 81 Crank 82 Crank 81a Pedal 82a Pedal 90 Driving plate (part of torque detection mechanism and deflection mechanism) 95 Deflection plate (part of torque detection mechanism and deflection mechanism) 96 Slide shaft (part of torque detection mechanism and deflection mechanism) 97 Spring (torque detection) 100 Torque sensor (torque detecting means) (part of torque detecting mechanism) 160 Speed sensor (vehicle speed detecting means) 200 Control device 201 Torque generation detecting means 202 Clocking means 203 Saturation determining means 204 Saturation Value storage means 205 cycle calculation means 206 assumed maximum torque value calculation means 207 Assumed current torque value calculation means 208 Motor output determination means 209 Motor control means

Claims (3)

[Claims] A bicycle with an electric power assist device that travels with power assistance from an electric motor. The bicycle has an excursion mechanism that operates according to the amount of expansion and contraction of a spring and that is deviated in accordance with the pedaling stepping torque. A torque detecting mechanism comprising torque detecting means for converting a stepping torque value into a voltage signal in accordance with the position amount and outputting the voltage signal, and detecting that a torque value is first detected by the torque detecting mechanism and a detection signal is output. Means for judging whether or not the detected torque value from the torque detecting mechanism is equal to or greater than a saturation value, and outputting a clock signal when the detected torque value is equal to or greater than the saturation value, and outputting the detected torque value when the detected torque value is less than the saturation value. A saturation determination means, a time measurement means for starting time measurement based on a detection signal of the detection means, measuring time until a time measurement signal from the saturation determination means, and outputting the time measurement time; Vehicle speed detecting means for detecting the speed, cycle calculating means for calculating a cycle of a torque signal detected by the torque detecting mechanism based on the vehicle speed detected by the vehicle speed detecting means, and a cycle from the cycle calculating means. Assumed maximum torque value calculating means for calculating an assumed maximum torque value based on the time measured from the timing means, and an assumed current torque value for calculating an assumed current torque value based on the assumed maximum torque value from the assumed maximum torque value calculating means. Torque value calculation means, motor output determination means for determining the output value of the motor based on one of the estimated current torque value from the assumed current torque value calculation means or the detected torque value from the saturation determination means, A control unit for controlling the electric motor based on an output value from the electric motor output determining unit. 2. The apparatus according to claim 1, further comprising: a storage unit in which a predetermined value is set, comparing said predetermined value with an assumed current torque value from said assumed current torque value calculation unit, and Outputting the predetermined value to the motor output determining means in place of the assumed current torque value when is equal to or greater than the predetermined value. 3. The invention according to claim 1, wherein the calculation of the assumed current torque value by the assumed current torque value calculation means is performed using a torque signal cycle based on the current vehicle speed. Bicycle with electric auxiliary power unit.