JP2007164811A - Wireless sensor - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a bearing unit with a sensor which is provided with a power source unit capable of supplying stable electric power and outputs detected signals on radio. <P>SOLUTION: A wireless sensor 21 is provided with a detection part 29 which detects detection objects; a control part 30 which processes detected signals of the detection part; a transmitting part 31 which transmits output being controlled by the control part by ultrasonic wave (or radio) W; and a power supply unit 32 which supplies electric power to the detection part, the control part, and transmitting part. This power supply unit is provided with a dynamo 33 having a coil and a magnetic flux change means which changes magnetic flux passing this coil, a secondary cell (storage battery part) 34 which stores electricity generated by the dynamo and discharges it, and a charge circuit 35 which controls storing and discharge of the storage battery part. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a wireless sensor that is incorporated in a part that relatively moves, such as a bearing or a linear motion device used in a machine tool, an industrial machine, a vehicle, and the like, and detects a detection target and outputs it wirelessly.

  Bearings that support rotating shafts, which are the axles of vehicles such as automobiles and railway vehicles, and linear motion devices and bearings such as ball screws and linear guides that are applied to industrial machines such as processing machines and assembly equipment, vibrate by movement. It generates or generates heat due to friction. These vibrations and temperatures affect the life of bearings and linear motion devices. Therefore, especially for bearings and linear motion devices that are attached to parts that are difficult to inspect, such as the inside of the device, a general-purpose vibration sensor or temperature sensor is prepared separately, and the target parts are provided as necessary. The detection signal is output via a signal line. When the vibration sensor or the temperature sensor requires electric power, the electric power is supplied through a feeder line.

  Further, the present inventor has attempted to provide a wireless sensor on the rolling bearing, supply electric power to the sensor by a primary battery, and transmit a detection signal by radio waves.

  When a detection signal is output through the signal line, a stable output signal can be obtained. When power is supplied through the feeder line, stable power supply can be obtained. In many cases, the signal line and the power supply line are usually used as a multicore cable (hereinafter abbreviated as a cable) bundled together. However, the sensor to which the cable is connected cannot be directly attached to the rotating side of the bearing. Moreover, when the sensor connected with the cable is attached to the movable body of the linear motion device, the cable may be repeatedly bent and disconnected.

  A wireless sensor reduces power consumption by outputting radio waves when a preset threshold value is exceeded, and can be used for a relatively long period of time by including a primary battery. However, since the power is consumed due to, for example, the vibration exceeding the threshold being output for a long time, the primary battery must be replaced.

  In addition, a stable power source is necessary to continuously detect the detection target. In bearings provided in places where a stable rotational speed can be obtained, such as a rotating shaft of a power source, a stable electric power is supplied to the sensor by providing a face-to-face generator, but industrial machines such as processing machines and assembly equipment A linear motion device such as a bearing or a ball screw or a linear guide provided in the motor is difficult to supply a stable power because the speed fluctuates or moves intermittently.

  Therefore, an object of the present invention is to provide a wireless sensor that includes a power supply device capable of supplying stable power and outputs a detected signal wirelessly.

  A wireless sensor according to the present invention includes a detection unit, a control unit, a transmission unit, and a power supply device. The detection unit detects a detection target. The control unit processes the detection signal of the detection unit. The transmission unit is controlled by the control unit to transmit the output wirelessly. The power supply device supplies power to the detection unit, the control unit, and the transmission unit. The power supply device includes a generator, a power storage unit, and a charging circuit. The generator has a coil and magnetic flux variation means for changing the magnetic flux passing through the coil. The power storage unit stores and discharges electricity generated by the generator. The charging circuit controls power storage and discharging of the power storage unit.

  Another wireless sensor according to the present invention includes a detection unit, a control unit, a transmission unit, and a power supply device. The detection unit detects a detection target. The control unit processes the detection signal of the detection unit. The transmission unit is controlled by the control unit to transmit the output wirelessly. The power supply device supplies power to the detection unit, the control unit, and the transmission unit. The power supply device includes a generator, a power storage unit, and a charging circuit. The generator has a thermoelectric generator. The power storage unit stores and discharges electricity generated by the generator. The charging circuit controls power storage and discharging of the power storage unit.

  By supplying electric power to the detection unit, the control unit, and the transmission unit with a power generation device including a generator and a power storage unit, a wireless sensor that can supply power stably with less frequency of component replacement can be obtained.

  A wireless sensor 1 according to a first embodiment of the present invention will be described with reference to FIGS. 1 and 2. A slide table 2 shown in FIG. 1 includes a ball screw 3. Both ends of the screw shaft 4 of the ball screw 3 are rotatably supported by bearings 6 fixed to the base 5. A motor 7 serving as a drive unit is connected to one end of the screw shaft 4 by a coupling 8. The table 9 is fixed to the nut 10 of the ball screw 3 and moves smoothly in the axial direction when the screw shaft 4 rotates.

  A wireless sensor 1 is attached to the nut 10. The wireless sensor 1 includes a detection unit 11 that detects vibration of a ball screw 3 that is an example of a detection target, a control unit 12 that processes a signal detected by the detection unit 11, and a control unit 12 based on the result. And a transmission device 13 as a transmission unit that is controlled to wirelessly output the radio wave R.

  As shown in the block diagram of FIG. 2, the wireless sensor 1 includes a power supply device 14 that supplies power to each of the detection unit 11, the control unit 12, and the transmission device 13. The power supply device 14 includes a photoelectric conversion body that is a generator, such as a solar battery 15, and a secondary battery 16 that is a power storage unit. Between the solar battery 15 and the secondary battery 16, there is provided a charging circuit 17 having a diode provided so that the electricity accumulated in the secondary battery 16 does not flow backward, a function of preventing overcharge of the secondary battery 16, and the like. ing. In FIG. 2, a thick solid line indicates a power supply path, and a thin solid line indicates a signal path.

  When the light hits the wireless sensor 1, power is generated by the solar cell 15, power is supplied to the detection unit 11, the control unit 12, and the transmission device 13, and the surplus is stored in the secondary battery 16. When the capacity of the secondary battery 16 is full, the charging circuit 17 prevents overcharging. Further, when the light hitting the wireless sensor 1 is weakened and the output of the solar battery 15 is reduced, the power stored in the secondary battery 16 is released and the power is supplied to the detection unit 11, the control unit 12, and the transmission device 13. Since the solar cell 15 is employed as the generator, when the amount of light is insufficient and the power is insufficient, it can be easily compensated by irradiating light from the outside.

  Thus, since the power supply device 14 of the wireless sensor 1 includes the solar battery 15 that is a generator, it is not necessary to replace parts due to battery exhaustion. In addition, since the power supply device 14 includes the secondary battery 16 together with the solar battery 15, stable power is supplied to the detection unit 11, the control unit 12, and the transmission device 13 even if the amount of light hitting the nut 10 slightly changes. Can do.

  Next, a wireless sensor 21 according to a second embodiment of the present invention will be described with reference to FIGS. In the bearing 22 shown in FIG. 3, the outer ring 23 is fitted to the housing 24, and the inner ring 25 is fitted to the middle of the rotating shaft 26. Further, a recess 28 is provided in a part of the end 27 of the outer ring 23, and the wireless sensor 21 is attached.

  As shown in the block diagram of FIG. 4, the wireless sensor 21 includes a detection unit 29 that detects a temperature that is an example of a detection target, a control unit 30 that processes a signal detected by the detection unit 29, and a result thereof. The transmitter 31 is controlled by the control unit 30 based on the above, and a transmitter 31 as a transmitter that wirelessly outputs a sound, for example, an ultrasonic wave W. The wireless sensor 21 includes a power supply device 32 that supplies power to the detection unit 29, the control unit 30, and the transmission device 31. The power supply device 32 includes a generator 33 that generates power by a change in magnetic flux (inductive electromotive force) according to the principle of electromagnetic induction, a secondary battery 34 that is a power storage unit that temporarily stores generated electricity, and a charging circuit 35. I have. The charging circuit 35 converts the electricity generated by the generator 33 into a direct current so that the secondary battery 34 can be charged, and has a function of preventing the secondary battery 34 from being overcharged. In FIG. 4, a thick solid line indicates a power supply path, and a thin solid line indicates a signal path.

  The generator 33 includes an electromotive portion 36 fixed to the outer ring 23 of the bearing 22 and a gear 37 fixed to the inner ring 25 serving as a derivative thereof. The gear 37 may be provided integrally with the inner ring 25. When the wireless sensor 21 is attached to the inner ring 25, the electromotive unit 36 is attached to the inner ring 25 and the gear 37 is attached to the outer ring 23. The gear 37 may be a gear provided as a part of the apparatus, or may be a dedicated gear. The electromotive unit 36 includes a pole piece 39 disposed in the radial direction of the gear 37, a coil 40 wound around the pole piece 39, and a magnet 41 attached to the opposite side of the gear 37 via the pole piece 39. ing. The pole piece 39 may be a member that induces magnetic flux, for example, a member mainly composed of iron, preferably a rod-shaped component made of a ferromagnetic material. The gear 37, the pole piece 39, and the magnet 41 are an example of magnetic flux changing means that changes the magnetic flux passing through the coil 40.

  Therefore, when the rotating shaft 26 rotates, the tooth surface 37a of the gear 37 approaches or separates from the pole piece 39, whereby the magnetic flux passing through the pole piece 39 changes, and an induced electromotive force is applied to the coil 40 wound around the pole piece 39. It generates electricity by generating. Since the electricity generated by the induced electromotive force is normally alternating current, it is converted into direct current by the charging circuit 35 and then supplied to the detection unit 29, the control unit 30, and the transmission device 31 and stored in the secondary battery 34.

  The electricity stored in the secondary battery 34 is released when the rotation speed of the rotary shaft 26 becomes slow and the output of the generator 33 is insufficient, or when the power is stopped and power is not generated, and is controlled by the detection unit 29. Electric power is supplied to the unit 30 and the transmitter 31.

  Thus, by providing the power supply device 32 with the induction excitation type generator 33, it is possible to supply power to the wireless sensor 21 without providing a primary battery. In addition, since the secondary battery 34 is provided, stable power can be supplied without interruption even when the rotational speed of the rotary shaft 26 decreases or stops.

  Next, a wireless sensor 51 according to a third embodiment of the present invention will be described with reference to FIGS. The vibration device 52 illustrated in FIG. 5 includes a linear guide 53 and a hydraulic cylinder 54. The hydraulic cylinder 54 is connected to a table 56 mounted on the bearing 55 of the linear guide 53, and reciprocates the table 56 along the linear guide 53 by expansion and contraction of the piston 57.

  A wireless sensor 51 is attached to the table 56. The wireless sensor 51 includes a detection unit 59 that detects pressure or strain, which is an example of a detection target, in order to measure a change in acceleration acting on the test body 58 placed on the table 56. Further, as shown in the block diagram of FIG. 6, the wireless sensor 51 includes a control unit 60 that processes a signal detected by the detection unit 59, and controls the control unit 60 based on a result thereof to output light, for example, infrared P. A transmitter 61 as a transmitter that outputs wirelessly, a detector 59, a controller 60, a power supply device 62 that supplies power to the transmitter 61, and a primary battery 63 are provided. The power supply device 62 includes a thermoelectric generator 64 that is a generator, a secondary battery 65 that is a power storage unit that temporarily stores generated electricity, and a charging circuit 66. The thermoelectric generator 64 is an element that generates power directly by a so-called Seebeck effect, which generates power directly by a temperature difference. The charging circuit 66 includes a diode that prevents the reverse flow of electricity stored in the secondary battery 65 and a function of preventing overcharge of the secondary battery 65. Further, the control unit 60 detects the voltage of the secondary battery 65 through the signal line 69 in order to know the amount of power stored in the secondary battery 65. In FIG. 6, a thick solid line indicates a power supply path, and a thin solid line indicates a signal path.

  The power supply device 62 and the primary battery 63 are provided in parallel, and the connection to the load side is switched by the first switch 67 and the second switch 68 controlled by the control unit 60, respectively. When the thermoelectric generator 64 can supply sufficient power, the first switch 67 is closed, the second switch 68 is opened, and the detection unit 59, the control unit 60, and the transmission device 61 as loads are connected. While supplying electric power, the surplus electric power is stored in the secondary battery 65. Although the electromotive force of the thermoelectric generator 64 may fluctuate due to a change in the temperature of the outside air or a load on the power consumption side, stable power is supplied by discharging the electricity stored in the secondary battery 65.

  Further, when the temperature difference generated in the thermoelectric generator 64 is small, or when the power consumption is large due to large power consumption, both the first switch 67 and the second switch 68 are closed, and the primary switch The battery 63 compensates for the shortage of power. Further, when there is almost no temperature difference generated in the thermoelectric generator 64 and sufficient power cannot be obtained, the first switch 67 is opened after the second switch 68 is closed, and the primary battery 63 is opened. To supply power.

  Therefore, when power is sufficiently supplied to the detection unit 59, the control unit 60, and the transmission device 61 by the power supply device 62, since the second switch 68 is in an open state, the primary battery 63 is prevented from consuming power. Life is extended. In addition, since a primary battery with a small battery capacity can be used, the wireless sensor 51 can be further downsized.

  As described above, by using the power supply device 62 including the thermoelectric generator 64 and the secondary battery 65 together with the primary battery 63, more stable power can be supplied to the detection unit 59, the control unit 60, and the transmission device 61. it can. Although both the first switch 67 and the second switch 68 are shown in the closed state in FIG. 6, they are so-called b contact switches that are excited by the control unit 60 and opened. In order to constantly supply power to the unit 60, the first switch 67 and the second switch 68 are opened and closed so that at least one of them is always closed. The first switch 67 and the second switch 68 may be not only mechanical contacts but also semiconductor switches such as transistors and FETs (Field Effect Transistors).

  In the first to third embodiments, the wireless sensors 1, 21, 51 are applied to the ball screw 3, the bearing 22, and the vibration device 52, respectively, but the linear sensor applied to the vibration device 52 is described. The wireless sensors 1, 21, 51 may be attached to a linear motion device such as the guide 53.

  In the first to third embodiments, when the ball screw 3, the bearing 22, or the vibration device 52 repeats rotating and moving intermittently, the power supply devices 14 of the wireless sensors 1, 21, 51, A so-called kinetic energy conversion type generator is used in which 32 or 62 power generation units amplify the rotational motion or swing motion of a weight (inertial body) with a gear to rotate a power generation rotor and generate an induced electromotive force in a coil. Also good.

  The generator of the first embodiment is the solar cell 15, the generator of the second embodiment is the electromagnetic induction generator 33, and the generator of the third embodiment is the thermoelectric generator 64. Therefore, a solar cell, an electromagnetic induction generator, a thermal power generation element, a kinetic energy conversion type generator can be used alone or in combination depending on the use state of the wireless sensor, and further primary. You may provide together with a battery. Further, although the power storage unit is the secondary battery 16, 34, 65, it can be replaced with a capacitor.

  The detection unit 11 of the first embodiment detects vibration, the detection unit 29 of the second embodiment detects temperature, and the detection unit 59 of the third embodiment detects pressure or strain. Since it is one form in carrying out, each detection part 11, 29, 59 is independent so that a vibration, temperature, pressure, distortion, humidity, speed, an angle, etc. can be detected according to the purpose of use, or You may provide in combination.

  Furthermore, the transmission unit of the first embodiment is a transmission device 13 that wirelessly outputs with radio waves R, the transmission unit of the second embodiment is a transmission device 31 that wirelessly outputs with ultrasonic waves W, and the transmission unit of the third embodiment is Although the transmitter 61 wirelessly outputs with the infrared P, any transmitter corresponding to the usage condition of the wireless sensor and the condition on the side of receiving the output may be used, so the transmitter of the wireless sensor 1 outputs with the ultrasonic wave W. The transmitting device 31 or the transmitting device 61 that outputs by infrared P may be used, and the transmitting device of the wireless sensor 21 may be the transmitting device 13 that outputs by radio wave R or the transmitting device 61 that outputs by infrared P. The transmitter of the wireless sensor 51 may be a transmitter that outputs the radio wave R or a transmitter 31 that outputs the ultrasonic wave W.

  In addition, as described above, the wireless sensors 1, 21 and 51 output the detection target wirelessly, and therefore may be applied to the stationary side of a bearing where it is difficult to take out a signal by wire.

  A wireless sensor 71 according to a fourth embodiment of the present invention will be described with reference to FIGS. Note that the same components as those of the wireless sensors 1, 21, 51 of the first to third embodiments are denoted by the same reference numerals and description thereof is omitted.

  The wireless sensor 71 shown in FIG. 7 includes the detection unit 11, the control unit 12, the transmission device 13, the secondary battery 16 of the power supply device 14 and the charging circuit 17 shown in the block diagram of FIG. The solar cell 15, which is an example of a body, and an antenna 73 are attached to the outer surface of the sensor case 72. The solar cell 15 should just be an area which can supply sufficient electric power to the detection part 11, the control part 12, and the transmitter 13. FIG. Specifically, as shown in FIG. 7A, for example, it may be attached to a surface (upper surface) 72t opposite to the installation surface in contact with the mounting portion of the housing H that houses the bearing whose detection target is measured, It may be attached to a surface (side surface) 72s rising from the installation surface as shown in FIG. 7B, or may be attached to all surfaces 72t and 72s except the installation surface as shown in FIG. 7C. Alternatively, it may be partially attached to the area exposed to light. At this time, the solar cell 15 is attached to each surface by bonding or screwing. The antenna 73 passes through the sensor case 72 and is connected to the transmission device 13. The antenna 73 may be of any form that can suitably output the radio wave R, and may be a loop-shaped or planar antenna other than the rod-shaped antenna 73 shown in FIG. You may change according to the surrounding environment in which the sensor 71 was installed. It may be other than a rod-like one attached to the side surface 72s. The shape of the installation surface of the wireless sensor 71 is flat in FIG. 7, but is preferably made according to the shape of the mounting portion of the housing H. In addition to fixing the housing H with a screw as shown in FIG. 7, when the mounting portion of the housing H is a ferromagnetic body, a magnet is attached to the installation surface, and the magnet's adsorption force makes it wireless. The sensor 71 may be fixed to the object to be measured, or may be attached with an adhesive. The shape of the sensor case is not limited to the box shape shown in FIG. 7, but may be a cylindrical shape or a hemispherical dome shape. In this case, the solar cell is attached in a range where the light from the sensor case is irradiated.

  The wireless sensor 71 configured as described above charges the secondary battery 16 with the surplus power out of the power generated by the solar battery 15 by the charging circuit 17. When the amount of light decreases, the power stored in the secondary battery 16 is discharged, and the power generated by the solar battery 15 is supplemented. Therefore, the wireless sensor 71 is not limited to an environment in which the solar cell 15 always obtains a necessary and sufficient amount of light, but also when the power generated by the solar cell 15 decreases due to a decrease in the amount of light. By supplementing the power from the power source, stable power can be supplied to the detection unit 11, the control unit 12, and the transmission device 13. In addition, since the wireless sensor 71 includes the transmission device 13 and the power supply device 14, there is no electric wire for supplying power and an output line for a signal detected by the detection unit. Therefore, the sensor case 72 includes a necessary sensor unit for detecting vibration, temperature, moving speed, rotation angle, pressure, strain, humidity, and the like, which are examples of detection objects, as the detection unit 11. By simply attaching the sensor 71 to the measurement target, a desired detection target can be detected and an output signal thereof can be obtained.

  As described in the first to third embodiments, signal propagation can use radio waves, light including infrared rays, sound waves including ultrasonic waves, and the like. At this time, radio waves and light are suitable in an environment where direct observation is possible, and radio waves are suitable in an environment where direct observation is possible but there are no obstacles. Sound waves can be used regardless of the presence or absence of obstacles, so in addition to sending signals in the atmosphere, signals can be sent through metal structures such as mechanical devices or in fluids such as underwater. Or send a signal.

  When a plurality of wireless sensors 71 are used simultaneously, identification information assigned to each wireless sensor 71 is transmitted together with the detected signal. As described above, by simultaneously managing the plurality of wireless sensors 71, it is possible to comprehensively monitor the operating state of the mechanical device or the like.

  A fifth embodiment according to the present invention will be described with reference to FIGS. In addition, about the same structure as 1st-4th embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted. As shown in FIG. 8, the wireless sensor 81 is built in a linear guide 82 which is an example of a linear motion device. The linear guide 82 includes a rail 83 and a bearing 84 that moves along the rail 83. The rail 83 has a rail groove 83a formed on the side surface along the direction in which the rail 83 extends. The bearing 84 is provided with a raceway groove 84a facing the rail groove 83a. A large number of rolling elements 85 that are in rolling contact with the rail groove 83 a and the raceway groove 84 a are loaded between the rail 83 and the bearing 84. The rolling element 85 circulates through a circulation path 86 provided in the bearing 84.

  As shown in the block diagram of FIG. 9, the wireless sensor 81 includes a detection unit 11, a control unit 12, a transmission device 13, and a power supply device 14. The transmission device 13 includes an antenna 87 that outputs the radio wave R, and transmits a signal detected by the detection unit 11 or information obtained by processing the signal by the control unit 12 from the antenna 87. The power supply device 14 includes a generator 88, a charging circuit 17, and a secondary battery 16. The generator 88 includes a coil 89, a pole piece 90, and a multipolar magnet 91 shown in FIG. The coil 89 is fixed to the bearing 84. The pole piece 90 is inserted into the coil 89 and guides the magnetic field lines coming out of the multipolar magnet 91 to the coil 89. The multipolar magnet 91 is attached to the upper surface 83b of the rail 83, and magnetizes the N pole 91n and the S pole 91s alternately along the direction in which the rail 83 extends. As the multipolar magnet 91, a rare earth magnet, a ferrite magnet or the like is used. The pole piece 90 and the multipolar magnet 91 are an example of magnetic flux changing means for changing the magnetic flux of the coil 89. The multipolar magnet 91 may be a magnetized pattern of the multipolar magnet 93 shown in FIG.

  When the coil 89 and the pole piece 90 move together with the bearing 84 along the rail 83, the direction of the magnetic flux passing through the coil 89 is reversed each time the N pole 91n and the S pole 91s pass alternately. As a result, an alternating induced current is generated in the coil 89. Further, when the movement of the bearing 84 is irregular, the generated electric power is unstable. Therefore, the charging circuit 17 converts the induced current into a direct current, supplies it to the detection unit 11, the control unit 12, and the transmission device 13, and charges the secondary battery 16 with surplus power. The electric power stored in the secondary battery 16 is supplied to the detection unit 11, the control unit 12, and the transmission device 13 with little voltage fluctuation.

  The generator 88 may be the coil 92 and the multipolar magnet 93 shown in FIG. Further, when the back yoke 94 is attached to the bearing 84 that is opposite to the multipolar magnet 93 across the coil 92, the magnetic field lines of the multipolar magnet 93 are effectively induced, and the induced current generated in the coil 92 is large. It will be good. When the magnetic pole pitch width m of the N pole 93n and the S pole 93s of the multipolar magnet 93 is made equal, and the winding width c of the coil 92 is equal to or less than the magnetic pole pitch width m of the multipolar magnet 93, preferably the same, the induced current is made efficient. Can be generated well. The multipolar magnet 93 shown in FIG. 10 may be the magnetization pattern of the multipolar magnet 91 shown in FIG. 8, but the magnetization pattern of the multipolar magnet 93 shown in FIG. 10 than the multipolar magnet 91 shown in FIG. 8. Is preferable because the magnetic flux can be used effectively.

  8 or 10, when the power generation amount of one coil 89 and 92 is less than the power consumption of the wireless sensor 81, a plurality of coils 89 and 92 are provided. The coils 89 and 92 can be connected in parallel to increase the current, and connected in series to increase the voltage. When a plurality of coils 89 and pole pieces 90 shown in FIG. 8 are provided, comb-shaped pole pieces may be formed in which one end of the pole piece 90 is integrally connected and the other end is directed to the multipolar magnet 91. In this case, the pitch of the comb teeth is preferably the same as the magnetic pole pitch width m of the multipolar magnet 91, and the winding direction of the adjacent coils 89 is preferably reversed.

  In the wireless sensors 1, 21, 51, 71, 81 shown in the first to fifth embodiments, when signals are transmitted from the transmitters 13, 31, 61, mobile communication means such as mobile phones, PHS (Personal Public lines such as Handyphone System) and satellite phones may be used. In this way, signals can be easily received at locations far away from the wireless sensors 1, 21, 51, 71, 81, and the wireless sensors 1, 21, 51, 71, 81 can be centrally managed at one location. It becomes like this. In addition, when a signal is output by the radio wave R, the signal may be transmitted directly from the transmitting device to the public line, or may be transmitted once to a repeater such as a receiving device disposed near the transmitting device 13. You may make it transmit to a public line from. Moreover, when a signal is output by the infrared ray P or the ultrasonic wave W, the signal is transmitted from there to a public line through a repeater such as a receiving device arranged nearby.

The figure which shows the state which attached the wireless sensor of the 1st Embodiment of this invention to the ball screw. The block diagram of the wireless sensor of FIG. Sectional drawing which shows the state which attached the wireless sensor of the 2nd Embodiment of this invention to the bearing. FIG. 4 is a block diagram of the wireless sensor of FIG. 3. The side view which shows the state which attached the wireless sensor of the 3rd Embodiment of this invention to the vibration excitation apparatus. FIG. 6 is a block diagram of the wireless sensor of FIG. 5. (A) is a perspective view which shows the state which attached the solar cell to the upper surface of a sensor case among the wireless sensors of the 4th Embodiment of this invention. (B) is a perspective view which shows the state which attached the solar cell to the side surface of the sensor case. (C) is a perspective view which shows the state which attached the solar cell to all surfaces other than an installation surface. The perspective view which shows a part notched bearing in the state which attached the wireless sensor of the 4th Embodiment of this invention to the linear guide. The block diagram of the wireless sensor of FIG. The perspective view which shows the other example of the electric power generation part of the wireless sensor of FIG.

Explanation of symbols

  1, 21, 51, 71, 81 ... wireless sensor, 11, 29, 59 ... detection unit, 12, 30, 60 ... control unit, 13, 31, 61 ... transmission device (transmission unit), 14, 32, 62 ... Power supply device, 15 ... solar cell (generator), 16, 34, 65 ... secondary battery (power storage unit), 17, 35, 66 ... charging circuit, 33, 88 ... generator, 37 ... gear (flux fluctuation means) , 39, 90... Pole piece (flux fluctuation means), 40, 89, 92... Coil, 41 .. magnet (flux fluctuation means), 63... Primary battery, 64 .. thermoelectric generator (generator), 91, 93. Polar magnet (magnetic flux fluctuation means), 91n, 93n ... N pole, 91s, 93s ... S pole, 94 ... back yoke (magnetic flux fluctuation means), R ... radio wave (wireless), W ... ultrasonic wave (wireless), P ... infrared ray (wireless).

Claims (4)

A detection unit that detects a detection target, a control unit that processes a detection signal of the detection unit, a transmission unit that is controlled by the control unit and transmits an output wirelessly, the detection unit, the control unit, and the transmission unit And a power supply device for supplying power to
The power supply device
A generator having a coil and magnetic flux variation means for changing the magnetic flux passing through the coil;
A power storage unit that stores and discharges electricity generated by the generator; and
A wireless sensor comprising: a charging circuit that controls power storage and discharge of the power storage unit.   2. The wireless sensor according to claim 1, wherein the magnetic flux fluctuation unit is a multipolar magnet in which N poles and S poles are alternately arranged in a direction moving relative to the coil. A detection unit that detects a detection target, a control unit that processes a detection signal of the detection unit, a transmission unit that is controlled by the control unit and transmits an output wirelessly, the detection unit, the control unit, and the transmission unit And a power supply device for supplying power to
The power supply device
A generator having a thermoelectric generator;
A power storage unit that stores and discharges electricity generated by the generator; and
A wireless sensor comprising: a charging circuit that controls power storage and discharge of the power storage unit. The power supply device further includes a primary battery,
The said control part connects at least any one of the said electrical storage part and the said primary battery to the said detection part, the said control part, and the said transmission part, and is made to supply electric power from the said power supply device. The wireless sensor according to any one of claims 1 to 3.

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