Wireless communication device

Abstract

To provide a wireless communication device that appropriately controls the power supply to the slave unit, reduces the power consumption of the slave unit during standby, and improves convenience. [Solution] The wireless communication device comprises a master unit and a slave unit that communicates wirelessly with the master unit. The slave unit has a main circuit including a receiving unit 414 that receives a normal operation start signal transmitted from the master unit, a power supply unit 34 that supplies power to each component of the slave unit, and a power control unit 43 that controls the power supply unit 34. Upon receiving a start signal, the power control unit 43 transitions from low-power control, which does not supply power to at least a part of the slave unit's main circuit 41, to temporary operation control, which supplies power to the receiving unit 414 and enables it to receive the normal operation start signal. If the normal operation start signal is received within a certain time after transitioning to temporary operation control, it transitions from temporary operation control to normal operation control, which supplies power to all components of the main circuit 41.

Description

Technical Field

[0001] The present invention relates to a wireless communication device in which a parent device and a child device perform wireless communication.

Background Art

[0002] A wireless communication device includes a parent device and a child device, and the parent device and the child device are configured to be capable of wireless communication. For example, when the child device is a measurement device that measures the state of a measurement target, the child device is attached to the measurement target. The child device has, for example, a power supply unit such as a secondary battery. By supplying power to the child device circuit from this power supply unit, the child device operates electrically. However, if power continues to be supplied even in a situation where the child device does not need to operate, that is, during standby, the power supply unit will be consumed further, and the net measurement time will be reduced.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of Invention

Problem to be Solved by the Invention

[0004] Accordingly, there is a method in which a power switch is provided in the child device, and power supply from the power supply unit to the child device circuit is cut off by turning the power switch on and off, so that power consumption during standby is limited only to natural discharge. However, there are cases where it is difficult for a user to go near the child device, and when the number of child devices is large, workability is poor.

[0005] There is also a method of cutting off the power supply for a preset time, and automatically starting the power supply when the set time elapses. However, in this case, it is necessary to wait for the set time, and it is not possible to respond to a case where the child device is to be used unexpectedly, or an exceptional and complicated measure is required.

[0006] The present invention was made to solve the above problems, and its purpose is to provide a wireless communication device that appropriately controls the power supply to the slave unit circuit, reduces the power consumption of the slave unit during standby, and improves convenience. [Means for solving the problem]

[0007] To achieve the above objective, the wireless communication device of the present invention comprises a master unit and a slave unit that communicates wirelessly with the master unit, wherein the slave unit is a receiving unit that receives a normal operation start signal transmitted from the master unit. Main circuit including The system includes a power supply unit that supplies power to each component of the slave unit, and a power control unit that controls the power supply unit. A sensor that detects a physical quantity without contact, and a determination unit that determines whether the detection result of the sensor exceeds a preset threshold, The power control unit has, If the determination unit determines that the detection result exceeds the threshold, it will be determined that a startup signal has been received. Transition from low-power control, which does not supply power to at least a part of the main circuit of the slave unit, to temporary operation control, which supplies power to the receiving unit and enables it to receive the normal operation start signal. Let If the normal operation start signal is received within a certain time after transitioning to the provisional operation control, the system transitions from provisional operation control to normal operation control, which supplies power to all components of the main circuit. Let It is characterized by the following: Furthermore, the wireless communication device of the present invention comprises a master unit and a slave unit that communicates wirelessly with the master unit, wherein the slave unit includes a main circuit including a receiving unit that receives a normal operation start signal transmitted from the master unit, a power supply unit that supplies power to each component of the slave unit, a power control unit that controls the power supply unit, a capacitor, and a determination unit that determines whether or not the capacitor has been charged, wherein the power control unit, when the determination unit determines that the capacitor has been charged, receives a start signal and transitions from low-power control, which does not supply power to at least a part of the main circuit, to temporary operation control, which supplies power to the receiving unit and enables the reception of the normal operation start signal, supplies power from the capacitor to the receiving unit, and if the normal operation start signal is received within a certain time after transitioning to the temporary operation control, transitions from temporary operation control to normal operation control, which supplies power to all components of the main circuit. Furthermore, the wireless communication device of the present invention comprises a master unit and a slave unit that communicates wirelessly with the master unit, wherein the slave unit is a measuring device and includes a main circuit including a receiving unit that receives a normal operation start signal transmitted from the master unit, a power supply unit that supplies power to each component of the slave unit, a power control unit that controls the power supply unit, a measuring unit that detects the state of the object to be measured, and a determination unit that determines whether the detection result of the measuring unit exceeds a preset threshold, wherein the power control unit, when the determination unit determines that the detection result exceeds the threshold, has received a start signal and transitions from low-power control, which does not supply power to at least a part of the main circuit, to temporary operation control, which supplies power to the receiving unit and enables the reception of the normal operation start signal, and if the normal operation start signal is received within a certain period of time after transitioning to the temporary operation control, it transitions from temporary operation control to normal operation control, which supplies power to all components of the main circuit. [Effects of the Invention]

[0008] According to the present invention, it is possible to obtain a wireless communication device that appropriately controls the power supply to the slave unit circuit, reduces the power consumption of the slave unit during standby, and improves convenience. [Brief explanation of the drawing]

[0009] [Figure 1] This is a block diagram showing the configuration of a wireless communication device according to the first embodiment. [Figure 2] This is a block diagram of the control unit of the slave unit according to the first embodiment. [Figure 3] This is a flowchart showing the operation of the wireless communication device according to the first embodiment. [Figure 4]This is a block diagram of the control unit of the slave unit according to the second embodiment. [Figure 5] This is a flowchart showing the operation of the wireless communication device according to the second embodiment. [Figure 6] This is a block diagram showing the configuration of a wireless communication device according to the third embodiment. [Figure 7] This is a flowchart showing the operation of the wireless communication device according to the third embodiment. [Modes for carrying out the invention]

[0010] [First Embodiment] A wireless communication device of the first embodiment will be described with reference to the drawings. The wireless communication device 1 comprises a master unit 2 and a slave unit 3. The master unit 2 and the slave unit 3 transmit and receive various signals wirelessly. In this embodiment, the slave unit 3 is a measuring device that detects the state of the object to be measured. The master unit 2 receives the detection result detected by the slave unit 3. Specifically, the slave unit 3 detects strain, and the master unit 2 calculates torque based on the strain received from the slave unit 3.

[0011] [Main unit] The master unit 2 consists of processing circuits such as a processor that operates according to a program, and storage media such as memory that stores programs and data. The master unit 2 receives detection results from the slave unit 3 and calculates, displays, and records measured values ​​based on the received detection results. The master unit 2 has a transmitting unit 21, a receiving unit 22, a calculation unit 23, and a display unit 24.

[0012] The transmitting unit 21 transmits signals such as a signal to start normal operation to the slave unit 3 according to the instructions of the control unit. The receiving unit 22 receives detection results such as strain from the slave unit 3. The transmitting unit 21 and the receiving unit 22 are able to communicate wirelessly with the transmitting unit 413 and the receiving unit 414 of the slave unit 3, which will be described later.

[0013] The calculation unit 23 calculates torque based on the strain received by the reception unit 22. The calculation unit 23 calculates torque by a method preset in a storage unit (not shown). The display unit 24 is, for example, a monitor or the like, and displays various types of information such as the torque calculated by the calculation unit 23.

[0014] [Slave unit] The slave unit 3 is a measuring device that detects strain of a measurement target. The slave unit 3 is, for example, a torque detector that detects torque with the shaft SF of a vehicle as the measurement target. That is, the slave unit 3 is attached to the shaft SF of the vehicle. The slave unit 3 includes a housing 31, a grip portion 32, a measurement unit 33, a power supply unit 34, a sensor 35, and a control unit 4.

[0015] The housing 31 is a container attached to the measurement target. The housing 31 of the present embodiment is attached so as to cover the shaft SF. The housing 31 accommodates the grip portion 32, the measurement unit 33, the power supply unit 34, and the control unit 4. The grip portion 32 is an element that comes into contact with and grips the measurement target. The grip portion 32 of the present embodiment comes into contact with and grips two positions separated in the axial direction of the shaft SF.

[0016] The measurement unit 33 is an element that detects the state of the measurement target. The measurement unit 33 includes a strain generating portion 331 and a strain gauge 332. The strain generating portion 331 is an element that can be attached to the measurement target. The strain generating portion 331 of the present embodiment is attached to the measurement target via the grip portion 32. More specifically, the strain generating portion 331 is a plate body that connects the two grip portions 32.

[0017] The strain gauge 332 constitutes a bridge circuit, and the output voltage of the bridge circuit changes according to the strain of the strain generating portion 331. In the present embodiment, the strain generating portion 331 is attached to the measurement target, and the strain gauge 332 is provided so as to be capable of indirectly detecting the strain of the measurement target. More specifically, the strain gauge 332 is not directly affixed to the shaft SF of the vehicle, but is affixed to the strain generating portion 331 attached to the shaft SF.

[0018] The power supply unit 34 is a rechargeable battery (secondary battery) that supplies power to each electrical component of the slave unit 3. Each component starts or stops depending on whether or not power is supplied by the power supply unit 34. The sensor 35 has an element that detects physical quantities such as vibration and heat in a contact manner, or an element that detects physical quantities such as light, sound, and magnetism in a non-contact manner. The sensor 35 in this embodiment is an optical sensor that detects light. This light becomes a start signal, and the power supply destination is changed by the power control unit 43, which will be described later. The sensor 35 is located on the outside of the housing 31.

[0019] The control unit 4 controls each part of the slave unit 3. The control unit 4 has a processor that executes programs to realize the various functions of the slave unit 3, a memory that stores various information such as programs and operating conditions, and drive circuits that drive each element. As shown in Figure 2, the control unit 4 has a main circuit 41, a determination unit 42, and a power control unit 43.

[0020] The main circuit 41 controls the main elements necessary for the slave unit 3 to detect the strain of the object to be measured. The main circuit 41 includes a measurement control unit 411, a calculation unit 412, a transmission unit 413, and a reception unit 414.

[0021] The measurement control unit 411 detects the voltage of the bridge circuit output in accordance with the strain of the strain generating unit 331. The calculation unit 412 calculates the strain from the voltage change detected by the measurement control unit 411.

[0022] The transmitting unit 413 transmits various signals to the master unit 2. The transmitting unit 413 transmits the strain and other values ​​calculated by the calculation unit 412 to the master unit 2. The receiving unit 414 receives various signals from the master unit 2. The receiving unit 414 receives a normal operation start signal from the master unit 2. The normal operation start signal is an instruction sent from the master unit 2 to supply power to all components of the slave unit 3, such as the main circuit 41, and to prepare the slave unit 3 to begin measuring the object to be measured.

[0023] The determination unit 42 compares the detection result of the physical quantity detected by the sensor 35 with a preset threshold, and determines that an activation signal has been received if the detection result exceeds the threshold, and instructs the power control unit 43 to transition to the provisional operation control state. In addition, the determination unit 42 maintains the provisional operation control instruction for a certain period of time after instructing the transition to the provisional operation control state. That is, the determination unit 42 has a threshold determination unit 421 and a time determination unit 422. In this embodiment, the physical quantity is the intensity of light, and the threshold determination unit 421 determines whether the detection result of the light intensity detected by the sensor 35 exceeds the threshold. If the light intensity exceeds the threshold, the threshold determination unit 421 determines that an activation signal to transition to the provisional operation control described later has been received. When the threshold determination unit 421 is implemented as a circuit, the threshold will be set as a voltage, which is equivalent to setting the threshold as a physical quantity of light intensity determined from the sensitivity of the sensor 35, the transmittance of its light receiving part, the threshold voltage, etc.

[0024] The power control unit 43 controls the power supply unit 34. The power control unit 43 changes the components to which power is supplied according to the control modes: low power consumption control, temporary operation control, and normal operation control. Low power consumption control is a state in which no measurement is performed, and at least some of the components of the main circuit 41 are not supplied with power. In the low power consumption control of this embodiment, power is not supplied to any of the components of the main circuit 41, namely the measurement control unit 411, the calculation unit 412, the transmission unit 413, and the receiving unit 414. In other words, in low power consumption control, power is supplied only to the sensor 35 and the determination unit 42. The low power consumption control can be activated after the measurement is completed when the user sends a measurement completion signal from the transmission unit 21 of the master unit 2, and the receiving unit 414 receives the signal.

[0025] Provisional operation control refers to a state in which, in addition to power supply by low-power consumption control, power is supplied only to the receiving unit 414 of the main circuit 41 that receives the normal operation start signal transmitted from the master unit 2, and to the elements involved in its processing. The elements involved in this processing are the elements that process the reception of the normal operation start signal and the elements that process the switching of the normal operation control. Provisional operation control activates only the elements involved in receiving the signal from the master unit 2 and processing after reception, and does not perform detection of the bridge circuit output voltage based on the resistance value of the strain gauge 332. The power control unit 43 transitions from low-power consumption control to provisional operation control when it receives a provisional operation control instruction issued when the threshold determination unit 421 determines that it has received an activation signal because the detection result of the light intensity detected by the sensor 35 has exceeded the threshold.

[0026] Normal operation control refers to a state in which power is supplied to all components of the slave unit 3, and strain measurement by the slave unit 3 can begin. Normal operation control is initiated only if the receiving unit 414 receives a normal operation start signal from the master unit 2 within a certain time period after transitioning from low-power consumption control to provisional operation control. The time determination unit 422 indirectly determines whether the reception of the normal operation start signal from the master unit 2 occurred within a certain time period by maintaining the provisional operation control state. This certain time period is predetermined and not limited to it, but for example, it is 10 seconds. In addition to this configuration, if the master unit 2 is equipped with an operation that always transmits a normal operation start signal once every 10 seconds while it is running, then the transition to normal operation control can be easily initiated by non-contact input of a startup signal to the slave unit 3 while the master unit 2 is running.

[0027] [Operation] Next, the transitions between low-power control, provisional operation control, and normal operation control will be explained using the flowchart in Figure 3. First, as a premise, it is assumed that the slave unit 3 is not performing any measurements and is in standby mode in low-power control mode (step S01). In other words, no power is supplied to the main circuit 41 of the slave unit 3.

[0028] First, when the user wants to start a measurement, they shine light towards the sensor 35. When light is shone on it, the sensor 35 detects the light and outputs a voltage or other value corresponding to the intensity of the detected light (step S02). Then, the threshold determination unit 421 compares the detected light intensity with a preset threshold (step S03).

[0029] If the light intensity detection result is below the threshold (step S03 No), the process returns to step S01 and low power consumption control is maintained. Steps S02 and S03 are repeated until the light intensity detection result exceeds the threshold. If the light intensity detection result exceeds the threshold (step S03 Yes), the process transitions to provisional operation control (step S04). That is, the power control unit 43 supplies power to the receiving unit 414 of the main circuit 41, enabling the slave unit 3 to receive normal operation instructions from the master unit 2.

[0030] Then, the receiving unit 414 of the slave unit 3 waits for the reception of a normal operation start signal from the master unit 2 (step S05 No). The time determination unit 422 indirectly determines whether the normal operation start signal has been received within a certain period of time. If the time determination unit 422 has not received the normal operation start signal within a certain period of time after transitioning to provisional operation control (step S05 No), it transitions from provisional operation control to low power consumption control (step S01). That is, the power control unit 43 stops supplying power to the receiving unit 414.

[0031] On the other hand, if the receiver 414 of the slave unit 3 receives a normal operation start signal from the master unit 2 within a certain period of time (step S05 Yes), it transitions from provisional operation control to normal operation control according to the instructions of the receiver 414 (step S06). That is, the power control unit 43 supplies power to the main circuit 41 in addition to the receiver 414, maintaining a state in which measurement by the slave unit 3 is possible. The normal operation start signal is transmitted from the transmitter 21 of the master unit 2 by the user operating the master unit 2. Alternatively, it may be transmitted repeatedly at regular intervals as long as the master unit 2 is running.

[0032] Then, when the receiver 414 of the slave unit 3 receives an instruction from the master unit 2 to start measurement, the measurement unit 33 measures the strain of the vehicle shaft SF, which is the object of measurement (step S07). The strain measurement continues until the receiver 414 of the slave unit 3 receives a signal indicating the end of measurement (step S08 No). When the measurement is complete, the user operates the master unit 2, and the transmitter 21 of the master unit 2 sends a signal indicating the end of measurement. When the receiver 414 of the slave unit 3 receives this signal (step S08 Yes), normal operation control ends and the system transitions to low power consumption control (step S01). That is, the power control unit 43 stops supplying power to the main circuit 41 and supplies power only to the sensor 35 and the determination unit 42.

[0033] [effect] As described above, the wireless communication device 1 of this embodiment comprises a master unit 2 and a slave unit 3 that communicates wirelessly with the master unit 2. The slave unit 3 includes a main circuit 41 that includes a receiving unit 414 that receives a normal operation start signal transmitted from the master unit 2, a power supply unit 34 that supplies power to each component of the slave unit 3, and a power control unit 43 that controls the power supply unit 34. Upon receiving a start signal, the power control unit 43 transitions from low-power control, which does not supply power to at least a part of the main circuit 41 of the slave unit 3, to temporary operation control, which supplies power to the receiving unit 414 and enables it to receive the normal operation start signal. If the normal operation start signal is received within a certain period of time after transitioning to temporary operation control, it transitions from temporary operation control to normal operation control, which supplies power to all components of the main circuit 41.

[0034] As a result, when the slave unit 3 is in standby mode and under low power consumption control, power is not supplied to at least a portion of the main circuit 41. Therefore, power consumption while the slave unit 3 is in standby mode can be significantly reduced.

[0035] Furthermore, upon receiving a startup signal, the system transitions from low-power control to provisional operation control. If the receiving unit 414 receives a normal operation start signal from the master unit 2 within a certain time after the transition, it switches back to normal operation control. Therefore, when a user wants to use the slave unit 3, the system can appropriately supply and maintain power to the components of the slave unit 3 in accordance with the operation of the master unit 2, thus improving convenience.

[0036] The time determination unit 422 issues an instruction to the power control unit 43 to switch from temporary operation control to low power consumption control if the receiving unit 414 does not receive a normal operation start signal within a certain period of time after transitioning to temporary operation control. This allows the system to return to low power consumption control in a relatively short time, even if it switches to temporary operation control due to a malfunction. Therefore, the power consumption of the power supply unit 34 can be reduced compared to continuing temporary operation control after a certain period of time has elapsed.

[0037] The power supply unit 34 is a rechargeable battery. This makes installation easy even when measuring rotating objects, and since it can be recharged and reused many times, costs can be reduced. In addition, the power consumption of the sub-unit 3 can be reduced, so it can be used for a long period of time on a single charge, improving productivity.

[0038] The slave unit 3 includes a non-contact sensor 35 for detecting physical quantities and a determination unit 42 for determining whether the detection result of the sensor 35 exceeds a preset threshold. When the determination unit 42 determines that the detection result exceeds the threshold, the power control unit 43 receives a start signal and transitions from low-power control to provisional operation control.

[0039] This allows the user to easily transition the slave unit 3 to provisional operation control by having the sensor 35 detect a signal corresponding to a threshold, thereby improving the convenience of the startup operation.

[0040] In particular, in this embodiment, the sensor 35 is a light sensor that detects light, and the determination unit 42 compares the detection result of the light intensity detected by the light sensor with a threshold value to determine whether the threshold value has been exceeded. For example, as in this embodiment, the installation location of the sub-unit 3 is narrow, making it difficult for the user to directly touch and operate it, as the sub-unit 3 is attached to the shaft SF of the vehicle. Even in such cases, the activation signal can be received using light, which is familiar to the user, thus improving workability and convenience.

[0041] [Second Embodiment] A wireless communication device of the second embodiment will be described with reference to the drawings. Note that components with the same configuration and functions as those of the first embodiment are denoted by the same reference numerals, and detailed descriptions are omitted. In the first embodiment, light was used as the activation signal, but in the second embodiment, the completion of charging of the capacitor 361 is used as the activation signal.

[0042] In this embodiment, as shown in Figure 4, the slave unit 3 has a sub-power supply unit 36. The sub-power supply unit 36 ​​has a capacitor 361 and an energy harvesting element 362. The capacitor 361 is an energy storage device that can store and discharge electricity. The energy harvesting element 362 is a component that obtains electricity by collecting energy such as sunlight, lighting, vibrations emitted by machinery, and heat. The capacitor 361 is charged by the electricity obtained by the energy harvesting element 362.

[0043] The threshold determination unit 421 determines whether or not the capacitor 361 has finished charging. If the capacitor 361 has finished charging, the threshold determination unit 421 determines that it has received a start signal. The power control unit 43 then transitions from low power consumption control to provisional operation control. When the power control unit 43 transitions from low power consumption control to provisional operation control, it uses the power of the capacitor 361. That is, the power supplied to the receiving unit 414 of the main circuit 41 uses the power of the capacitor 361.

[0044] Next, the operation of the slave unit 3 in this embodiment will be explained using the flowchart in Figure 5. First, the slave unit 3 is in standby mode with low power consumption control (step S01). In this standby state, charging of the capacitor 361 begins (step S11).

[0045] The threshold determination unit 421 determines whether the charging of the capacitor 361 is complete (step S12). Charging of the capacitor 361 continues until the charging of the capacitor 361 is complete (step S12 No). Note that charging continues even after the charging of the capacitor 361 is complete. If the threshold determination unit 421 determines that the charging of the capacitor 361 is complete, the power control unit 43 transitions from low power consumption control to provisional operation control, assuming that it has received a start signal (step S05). The power control unit 43 controls the power of the capacitor 361 to be supplied to the receiving unit 414 of the main circuit 41. As a result, the receiving unit 414 of the main circuit 41 becomes capable of receiving the normal operation start signal from the master unit 2. After that, the procedure is the same as in the first embodiment (steps S06 to S09).

[0046] As described above, in the wireless communication device 1 of this embodiment, the slave unit 3 has a capacitor 361, an energy harvesting element 362, and a determination unit 42 that determines whether or not the capacitor 361 has been charged. When the power control unit 43 determines that the capacitor 361 has been charged, it receives a start signal and transitions from low power consumption control to provisional operation control, and supplies power from the capacitor 371 to the receiving unit 414.

[0047] This allows power to be supplied to the receiver 414 from the capacitor 361 during temporary operation control. In other words, power to the receiver 414 is not supplied by the power supply unit 34. Therefore, while improving the convenience of startup operations, the power supply unit 34 is not consumed during temporary operation control, thus effectively reducing the power consumption of the slave unit 3 during standby and startup. Furthermore, in such a configuration, if the capacity of the capacitor 361 is appropriately designed, the power consumed by the receiver 414 will deplete the charge after a certain period of time, making it impossible to maintain temporary operation control. In other words, it is easy to achieve a transition from temporary operation control to low power consumption control without the time determination unit 422.

[0048] [Third Embodiment] A wireless communication device of the third embodiment will be described with reference to the drawings. Note that components with the same configuration and functions as those of the first embodiment are denoted by the same reference numerals, and detailed descriptions are omitted. In the first embodiment, the slave unit 3 had a sensor 35 in addition to a measurement unit 33 with a strain generating unit 331 and a strain gauge 332, and the sensor 35 detected light to determine the presence or absence of an activation signal.

[0049] On the other hand, in this embodiment, the presence or absence of a start signal is determined using the detection results obtained by the measurement unit 33, which is provided as a measuring device, namely the strain generating unit 331 and the strain gauge 332. In other words, as shown in Figure 6, the slave unit 3 of this embodiment does not have the sensor 35 that was provided in the first embodiment.

[0050] In the low-power control of this embodiment, power is supplied to the measurement control unit 411 of the main circuit 41. In this low-power control, it is sufficient to supply enough power to detect changes in the state of the object being measured. For example, it is sufficient to supply enough power to enable low-speed sampling at a predetermined rate, such as once per second. Low-speed sampling is analog-to-digital conversion and signal processing that reduces power consumption by reducing the number of processing steps per unit time compared to normal operation. For example, if the operating frequency in normal operation is 10 to 100 MHz, in low-power mode, processing is performed at several kHz to several hundred kHz. The measurement unit 33 continues to acquire the state of the object being measured during low-power control. In this embodiment, the measurement unit 33 detects strain associated with changes in the rotational load of the vehicle's shaft SF.

[0051] The threshold determination unit 421 compares the measurement result, which is a physical quantity measured by the measurement unit 33, with a threshold value and determines whether the measurement result exceeds the threshold value. In this embodiment, the physical quantity is the strain of the strain generating unit 331 measured by the measurement unit 33. If the measurement result from the measurement unit 33 exceeds the threshold value, the threshold determination unit 421 determines that a start signal has been received, and the power control unit 43 supplies power from the power supply unit 34 to the receiving unit 414.

[0052] The operation of the wireless communication device 1 in this embodiment will be explained using the flowchart in Figure 7. First, the slave unit 3 is in standby mode and in a low power consumption control state (step S01). Then, the rotational load of the vehicle shaft SF, which is the object of measurement, changes. The measurement unit 33 detects the strain associated with this rotational load (step S21).

[0053] The threshold determination unit 421 compares the strain detected by the measurement unit 33 with a threshold value and determines whether the detection result exceeds the threshold (step S22). If the threshold determination unit 421 determines that the threshold has not been exceeded (step S22 No), it continues measuring the change in rotational load in low power consumption control mode (step S01). On the other hand, if the detection result exceeds the threshold (step S22 Yes), the threshold determination unit 421 determines that it has received a start signal. The power control unit 43 then transitions from low power consumption control to provisional operation control, supplies power from the power supply unit 34 to the receiving unit 414, and becomes capable of receiving the normal operation start signal from the master unit 2. The process thereafter is the same as in the first embodiment (steps S06 to S09). Note that here the strain detected by the measurement unit 33 was compared with a threshold value, but the threshold determination unit 421 may also compare the amount of change in the detected strain with a corresponding threshold value, for example.

[0054] As described above, the wireless communication device 1 of this embodiment has a slave unit 3 which is a measuring device and includes a measuring unit 33 that detects the state of the object to be measured and a determination unit 42 that determines whether the measurement result detected by the measuring unit 33 exceeds a preset threshold. When the determination unit 42 determines that the measurement result exceeds the threshold, the power control unit 43 receives a start signal and transitions from low power consumption control to provisional operation control.

[0055] As a result, the determination unit 42 can determine the presence or absence of a startup signal based on the measurement results of the measurement unit 33 of the sub-unit 3, which is equipped as a measuring device. In other words, the sensor 35 becomes unnecessary, and the number of parts and costs can be reduced.

[0056] Furthermore, by using the measurement results of the state of the object being measured as an indicator of the presence or absence of a start signal, the measurement unit 33 can confirm in advance that the state of the object being measured is being measured correctly. Therefore, it is possible to prevent measurement failures during normal operation control due to improper installation of the slave unit 3 or other reasons.

[0057] In particular, in this embodiment, the measurement unit 33 performs low-speed sampling measurement during low-power control, and does not perform high-speed sampling measurement, which is the original operating state. Therefore, since the measurement unit 33 and the measurement control unit 411 are operated with minimal power to determine the presence or absence of a start signal, power consumption during low-power control can be reduced.

[0058] (Other embodiments) While embodiments of the present invention have been described herein, these embodiments are presented as examples and are not intended to limit the scope of the invention. The above embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the scope of the invention. Embodiments and their variations are included in the scope and essence of the invention, as well as in the claims and their equivalents.

[0059] The slave unit 3 may be equipped with a power switch that cuts off the power supply from the power supply unit 34 to all components of the slave unit 3. The power switch has an on / off button, and when the power switch is off, it cuts off the power supply from the power supply unit 34 to all components of the slave unit 3. For example, when the measurement of the object to be measured is complete and the slave unit 3 is to be stored, the user turns off this power switch. This completely cuts off the power supply from the power supply unit 34 to the sensor 35, measuring unit 33, etc. Therefore, the power consumption when the power switch is off can be reduced to only natural discharge, thus further reducing power consumption.

[0060] Furthermore, if the power supply to the threshold determination unit 421 and the time determination unit 422 can be separated, then during low-power control, power may not be supplied to the time determination unit 422, and power may be supplied only to the threshold determination unit 421. When switching from low-power control to provisional operation control, power may also be supplied to the time determination unit 422. This makes it possible to further reduce power consumption during low-power control.

[0061] In the above embodiment, the master unit 2 and the slave unit 3 transmitted or received various signals wirelessly, but they may also transmit or receive various signals via a wired connection.

[0062] In the above embodiment, the measurement unit 33 measured strain, but is not limited to this. The measurement unit 33 may also measure the state of the object to be measured, such as temperature or pressure. [Explanation of Symbols]

[0063] 1. Wireless communication device 2 Master Unit 21 Transmitter 22 Receiving section 23 Calculation Section 24 Display section 3. Handset 31 cabinets 32 Gripping part 33 Measurement Unit 331 Strain part 332 Strain Gauges 34 Power supply section 35 sensors 36 Sub-power supply section 361 Capacitors 362 Energy Harvesting Element 4. Control Unit 41 Main circuit 411 Measurement Control Unit 412 Arithmetic section 413 Transmitter 414 Receiving Unit 42 Judgment section 421 Threshold determination unit 422 Time determination unit 43 Power Control Unit

Claims

1. The main unit and A slave unit that communicates wirelessly with the aforementioned master unit, Equipped with, The aforementioned sub-unit is A main circuit including a receiving unit that receives a normal operation start signal transmitted from the master unit, A power supply unit that supplies power to each component of the aforementioned slave unit, A power control unit that controls the power supply unit, A sensor that detects physical quantities without contact, A determination unit that determines whether the detection result of the sensor exceeds a preset threshold, It has, The power control unit, If the determination unit determines that the detection result exceeds the threshold, it will assume that a start signal has been received and will transition from low-power control, which does not supply power to at least a part of the main circuit, to temporary operation control, which supplies power to the receiving unit and enables the reception of the normal operation start signal. If the normal operation start signal is received within a certain time after transitioning to the provisional operation control, the system will transition from the provisional operation control to the normal operation control, which supplies power to all components of the main circuit. A wireless communication device characterized by the following.

2. The main unit and A slave unit that communicates wirelessly with the aforementioned master unit, Equipped with, The aforementioned sub-unit is A main circuit including a receiving unit that receives a normal operation start signal transmitted from the master unit, A power supply unit that supplies power to each component of the aforementioned slave unit, A power control unit that controls the power supply unit, Capacitor and, A determination unit for determining whether the capacitor has been charged, It has, The power control unit, If the determination unit determines that the capacitor has been charged, it will receive a start signal and transition from low-power control, which does not supply power to at least a part of the main circuit, to temporary operation control, which supplies power to the receiving unit and enables the reception of the normal operation start signal, and the power of the capacitor will be supplied to the receiving unit. If the normal operation start signal is received within a certain time after transitioning to the provisional operation control, the system will transition from the provisional operation control to the normal operation control, which supplies power to all components of the main circuit. A wireless communication device characterized by the following.

3. The main unit and A slave unit that communicates wirelessly with the aforementioned master unit, Equipped with, The aforementioned sub-unit is a measuring device, A main circuit including a receiving unit that receives a normal operation start signal transmitted from the master unit, A power supply unit that supplies power to each component of the aforementioned slave unit, A power control unit that controls the power supply unit, A measurement unit that detects the state of the object to be measured, A determination unit that determines whether the detection result of the measurement unit exceeds a preset threshold, It has, The power control unit, If the determination unit determines that the detection result exceeds the threshold, it will assume that a start signal has been received and will transition from low-power control, which does not supply power to at least a part of the main circuit, to temporary operation control, which supplies power to the receiving unit and enables the reception of the normal operation start signal. If the normal operation start signal is received within a certain time after transitioning to the provisional operation control, the system will transition from the provisional operation control to the normal operation control, which supplies power to all components of the main circuit. A wireless communication device characterized by the following.

4. If the power control unit does not receive the normal operation start signal within a certain period of time after transitioning to the provisional operation control, it transitions from the provisional operation control to the low power consumption control. A wireless communication device according to any one of claims 1 to 3, characterized by the following:

5. The aforementioned power supply unit is a secondary battery. A wireless communication device according to any one of claims 1 to 3, characterized by the following:

6. The aforementioned sensor is a light sensor that detects light, The determination unit compares the detection result of the light sensor with the threshold and determines whether the threshold has been exceeded. A wireless communication device according to claim 1, characterized by the following:

7. The aforementioned sub-unit is a measuring device that detects the state of the object to be measured. A wireless communication device according to claim 1 or 2, characterized by the above.

8. The aforementioned slave unit has a power switch for switching the slave unit on or off, The power supply unit shall not supply power to any of the components constituting the slave unit when the power switch is off. A wireless communication device according to any one of claims 1 to 3, characterized by the following:

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