Measurement instrument, wireless power transfer apparatus, and wireless power transfer system

Abstract

The invention relates to a measuring instrument, a wireless power transfer apparatus, and a wireless power transfer system. A portable measuring instrument (1) is a portable measuring instrument to which power is supplied from a wireless power transmission device for wirelessly supplying power, the measuring instrument comprising: a sensor (117) capable of detecting a person using the measuring instrument (1); a signal transmission unit (119) for transmitting, to the wireless power transmission device, a beacon signal indicating the state of the measurement instrument detected by the sensor (117); and a power receiving antenna (110) for receiving power transmitted from the wireless power transmitting apparatus.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to a measuring instrument, a wireless power transfer device, and a wireless power transfer system for performing wireless power transfer. BACKGROUND

[0002] Japanese Patent 6725531 discloses a technique for wireless charging. SUMMARY

[0003] Problems to be Solved by the Invention

[0004] When wireless power transfer is performed, power is sent via space by being carried on a wireless wave, and when a wireless wave of high power is radiated onto a human, it can have an effect on the human body. Therefore, there is a need for wireless power transfer that does not have an effect on the human body.

[0005] The present disclosure focuses on this point, and the object is to suppress the effect on the human body when wireless power transfer is performed.

[0006] Solution to Problem

[0007] A portable measuring instrument according to an aspect of the present disclosure is a portable measuring instrument in which power is supplied from a wireless power transfer device for supplying power wirelessly to the measuring instrument, the measuring instrument including: a sensor capable of detecting a person using the measuring instrument; a signal transmission section for transmitting a beacon signal for indicating a state of the measuring instrument detected by the sensor to the wireless power transfer device; and a power reception antenna for receiving power transmitted from the wireless power transfer device.

[0008] Effects of the Invention

[0009] According to the present disclosure, it is possible to suppress the effect on the human body when wireless power transfer is performed. BRIEF DESCRIPTION OF DRAWINGS

[0010] Figure 1 An overview of the operation of the wireless power transfer system S is shown.

[0011] Figure 2 An example of the measuring instrument 1 without the power reception module is shown.

[0012] Figure 3 The relationship between the power reception module 11 and the housing portion ST of the measuring instrument 1 is shown.

[0013] Figure 4 An example of the structure of the measuring instrument 1 is shown.

[0014] Figure 5 An example of the structure of the power reception module 11 is shown.

[0015] Figure 6 is a schematic view of the power receiving module 11.

[0016] Figure 7 An example of the structure of the wireless power transfer apparatus 2 is shown.

[0017] Figure 8 Another example of the structure of the measuring instrument 1 is shown.

[0018] Figure 9 Another example of the structure of the wireless power transfer apparatus 2 is shown.

[0019] Figure 10 is a flowchart illustrating the process performed by the wireless power transfer apparatus 2.

[0020] Figure 11 Another example of the structure of the measuring instrument 1 is shown.

[0021] Figure 12 Another example of the structure of the wireless power transfer apparatus 2 is shown.

[0022] Figure 13 An example of the generation of the correction vector is shown.

[0023] Figure 14 An example of identifying the respective positions of the plurality of power receiving antennas 110 is shown.

[0024] Figure 15 is a flowchart illustrating the process performed by the wireless power transfer apparatus 2.

[0025] BRIEF DESCRIPTION OF DRAWINGS

[0026] S: wireless power transfer system

[0027] 1: measuring instrument

[0028] B: standard battery

[0029] ST: housing

[0030] C: cover

[0031] GR: groove

[0032] SW: switch

[0033] 11: power receiving module

[0034] 110: power receiving antenna

[0035] 111: power rectifying circuit

[0036] 112: RF demodulation circuit

[0037] 113: charging circuit

[0038] 114: secondary battery

[0039] 115: primary battery

[0040] 116: power transfer circuit

[0041] 117: sensor

[0042] 118: control circuit

[0043] 119: signal transmission section

[0044] 301: signal modulation circuit

[0045] 302: light emitting section

[0046] 12: main body section

[0047] 121: operation section

[0048] 122: display section

[0049] 123: memory

[0050] 124: controller

[0051] 401: determination section

[0052] 402: distance recognition section

[0053] 125: display device

[0054] 126: posture detection section

[0055] 2: wireless power transfer apparatus

[0056] 21: signal reception section

[0057] 211: light receiving section

[0058] 212: signal demodulation circuit

[0059] 22: power transmission section

[0060] 221: RF modulation circuit

[0061] 222: power transmission antenna

[0062] 23: memory

[0063] 24: controller

[0064] 241: position recognition section

[0065] 242: measuring instrument recognition section

[0066] 243: power reception position recognition section

[0067] 244: power transmission object recognition section

[0068] 245: power transmission controller

[0069] 25: signal transmitting section DETAILED DESCRIPTION

[0070] [Outline of wireless power transmission system S]

[0071] In order to transmit electric power to a small electronic measuring instrument, a battery needs to be provided in the electronic measuring instrument, but this raises problems such as the need for battery replacement and battery disposal. Therefore, in the wireless power transmission system S according to the present embodiment, a wireless power transmission apparatus for wirelessly transmitting electric power is configured to wirelessly transmit electric power to a portable measuring instrument. This makes it unnecessary to replace the battery and dispose of the battery.

[0072] Examples of the wireless power transmission method in the wireless power transmission system S include an electromagnetic induction method, a magnetic field resonance method, an electric field coupling method, a laser beam method, and a microwave method. Hereinafter, a case where the wireless power transmission method is the microwave method will be described as an example.

[0073] Figure 1 An outline of the operation of the wireless power transmission system S is shown. The wireless power transmission system S includes a wireless power transmission apparatus 2 for wirelessly transmitting electric power, and a measuring instrument 1 for receiving electric power transmitted from the wireless power transmission apparatus 2.

[0074] The measuring instrument 1 is a portable electronic device. The measuring instrument 1 is, for example, a digital caliper, a digital indicator, or a digital micrometer. Hereinafter, a case where the measuring instrument 1 is a digital micrometer will be described as an example.

[0075] The measuring instrument 1 includes i) a signal transmitting section for transmitting a beacon signal, and ii) a power receiving antenna for receiving electric power transmitted from the wireless power transmission apparatus 2. The beacon signal is a signal including information notified by the measuring instrument 1 to the wireless power transmission apparatus 2, and is, for example, an optical signal or a high-frequency signal (i.e., a radio wave). The beacon signal is, for example, a signal transmitted every several seconds to reach a range with a radius of several to several tens of meters. If the wireless power transmission apparatus 2 is located within a range where the beacon signal transmitted by the measuring instrument 1 reaches, the wireless power transmission apparatus 2 can receive the beacon signal and recognize the position of the measuring instrument 1.

[0076] The power receiving circuit including the signal transmitting section and the power receiving antenna is, for example, incorporated into a power receiving module having a portion with the same shape as that of a standard battery having a standardized size. The power receiving antenna is, for example, a pattern antenna. Thus, by modularizing the power receiving circuit, it is possible to realize wireless power transmission by attaching the power receiving module to an existing measuring instrument.

[0077] The wireless power transmission device 2 is a device for wirelessly transmitting electric power. The wireless power transmission device 2 includes: i) a signal receiving section (e.g., a light receiving device) for receiving a beacon signal; and ii) a power transmitting section (e.g., a power transmitting multi-antenna) for wirelessly transmitting electric power.

[0078] The flow of wireless power transmission in the present embodiment will be described with reference to Figure 1 The measuring instrument 1 transmits a beacon signal to the surroundings. The wireless power transmission device 2 receives the beacon signal transmitted from the measuring instrument 1 with the light receiving section 211. The wireless power transmission device 2 that has received the beacon signal wirelessly transmits electric power to the power receiving antenna of the measuring instrument 1 that has transmitted the beacon signal via the power transmitting antenna 222.

[0079] In order to suppress the influence of wireless power transmission on the human body, the wireless power transmission device 2 transmits electric power to the power receiving antenna of the measuring instrument 1 only in a case where it is determined that the measuring instrument 1 is located within a predetermined distance with respect to the wireless power transmission device 2 and that no person (operator) is using the measuring instrument 1. In addition, in order to improve the efficiency of wireless power transmission, the wireless power transmission device 2 can transmit electric power to the power receiving antenna among the plurality of power receiving antennas included in the measuring instrument 1 that can receive the largest amount of electric power transmitted by the wireless power transmission device 2.

[0080] The following description provides details regarding each of: i) the modularization of the power receiving circuit, ii) the suppression of the influence of wireless power transmission on the human body, and iii) the improvement of the efficiency of wireless power transmission.

[0081] <Modularization of the Power Receiving Circuit>

[0082] [Summary]

[0083] In the measuring instrument 1, a small battery such as a button cell is used. In order to enable wireless power transmission using the existing measuring instrument 1, instead of the battery, a power receiving module for wirelessly receiving electric power can be attached to the measuring instrument 1. However, it is difficult to fit the power receiving module including all the power receiving circuits necessary for wireless power transmission within the size of the button cell. On the other hand, when the size of the power receiving module increases, the power receiving module can no longer be attachable to the measuring instrument 1 designed to use the button cell.

[0084] Therefore, the present embodiment provides a power receiving module including: i) a first portion having the same shape as that of a button cell; and ii) a second portion having the same shape as that of a cover portion for covering the button cell in a state where the button cell is housed in a housing portion that can house the button cell in the measuring instrument 1. The power receiving module according to the present embodiment includes a power receiving antenna for receiving electric power transmitted from the wireless power transmission device 2.

[0085] The power receiving module includes a first portion so that the power receiving module can be attached to the battery housing of the existing measuring instrument 1 in place of the coin battery. Further, the power receiving module includes a second portion so that the total volume of the power receiving module is increased by the volume of the second portion, thereby enabling the power receiving circuit for wireless power transfer to be housed within the size of the coin battery. As described above, the power receiving module has the first portion and the second portion, thereby enabling the wireless power transfer to be implemented using the existing measuring instrument 1. The structure and operation of the measuring instrument 1 and the wireless power transfer device 2 will be described below.

[0086] [Structure and operation of measuring instrument 1]

[0087] Figure 2 An example of the measuring instrument 1 without the power receiving module is shown. Figure 2 (a) is a front view of the measuring instrument 1, and Figure 2 (b) is a back view of the measuring instrument 1. Figure 2 The measuring instrument 1 shown is a digital micrometer.

[0088] As shown in Figure 2 , the measuring instrument 1 includes a detachable cover portion C, and a main body portion 12 which is a portion of the measuring instrument 1 other than the cover portion C. A housing portion ST of the main body portion 12 is a portion capable of housing a standard battery B having a standardized size. The type of the standard battery B is not particularly limited, and is, for example, a coin battery. The cover portion C is a portion which covers the standard battery B in a state where the standard battery B is housed in the housing portion ST, and is a battery cover. The cover portion C is provided with a groove GR for turning the cover portion C. An operator can open and close the cover portion C by inserting a flathead screwdriver or a fingernail, etc. into the groove GR and turning the cover portion C. It should be noted that the power receiving module can be attached to the measuring instrument 1, but the power receiving module is not shown in Figure 2 .

[0089] Figure 3 The relationship between the power receiving module 11 and the housing portion ST of the measuring instrument 1 is shown. The power receiving module 11 is a physical device including a power receiving antenna for receiving power transferred from the wireless power transfer device 2. As shown in Figure 3 , the power receiving module 11 can be attached to the housing portion ST of the main body portion 12 of the measuring instrument 1. When the terminal T2 provided to the power receiving module 11 contacts the terminal T1 provided to the housing portion ST in a state where the power receiving module 11 is housed in the housing portion ST, the power received by the power receiving module 11 is transferred to the main body portion 12.

[0090] Figure 4 An example of the structure of the measuring instrument 1 is shown. The measuring instrument 1 includes the power receiving module 11 and the main body portion 12. The main body portion 12 includes an operation portion 121, a display portion 122, a memory 123, and a controller 124.

[0091] The operation section 121 is an operation device for receiving an operation from an operator, and is, for example, an operation button.

[0092] The display section 122 includes, for example, a liquid crystal display or an organic electroluminescence (EL) display, or the like. The display section 122 can be a light emitting diode (LED). The display section 122 displays a measurement result from the measuring instrument 1, thereby indicating that charging is required, or the like. Details of the processing performed by the display section 122 will be described later.

[0093] The memory 123 is a storage medium including a read only memory (ROM) and a random access memory (RAM), or the like. The memory 123 stores a program executed by the controller 124.

[0094] The controller 124 is, for example, a central processing unit (CPU). The controller 124 executes an information processing program stored in the memory 123. Details of the processing performed by the controller 124 will be described later.

[0095] Figure 5 An example of the structure of the power receiving module 11 is shown. The power receiving module 11 includes a power receiving antenna 110, a power rectification circuit 111, an RF demodulation circuit 112, a charging circuit 113, a secondary battery 114, a primary battery 115, a power transmission circuit 116, a sensor 117, a control circuit 118, and a signal transmission section 119. Note that the sensor 117 and the signal transmission section 119 can be provided in the main body section 12.

[0096] The power receiving antenna 110 is an antenna for receiving power transmitted from the wireless power transmission apparatus 2. A plurality of power receiving antennas 110 can be provided in the power receiving module 11.

[0097] The power rectification circuit 111 converts AC power received from the power receiving antenna 110 into DC power. The power rectification circuit 111 is a circuit for supplying the converted power to the charging circuit 113.

[0098] The RF demodulation circuit 112 demodulates an RF (high frequency) signal input from the power receiving antenna 110. The RF demodulation circuit 112 inputs the demodulated signal to the control circuit 118.

[0099] The charging circuit 113 is a circuit for supplying power received from the power rectification circuit 111 to the secondary battery 114. The charging circuit 113 switches between i) a state of supplying the power received from the power rectification circuit 111 to the secondary battery 114 and ii) a state of not supplying the power to the secondary battery 114, based on a control signal input from the control circuit 118.

[0100] The secondary battery 114 is a battery that is charged with the electric power received by the power receiving antenna 110. The secondary battery 114 is a storage battery that can be repeatedly used by being charged with electric power. Since the power receiving module 11 includes the secondary battery 114, the measuring instrument 1 can store the wirelessly transmitted electric power.

[0101] The primary battery 115 is, for example, a battery that is smaller than the standard battery B. The electric power capacity of the primary battery 115 can be smaller than the electric power capacity of the standard battery B. The primary battery 115 is a disposable battery that cannot be reused once it is completely discharged. As described in detail below, the power receiving module 11 includes the primary battery 115, which enables the measuring instrument 1 to use the electric power of the primary battery 115 when the remaining capacity of the secondary battery 114 is low and the measuring instrument 1 cannot receive electric power from the wireless power transmission device 2.

[0102] The power transmission circuit 116 is a circuit for transmitting the electric power received from the secondary battery 114 or the primary battery 115 to the main body section 12 of the measuring instrument 1. The power transmission circuit 116 can switch from which power source (the secondary battery 114 or the primary battery 115) to transmit electric power. The power transmission circuit 116 switches from which power source (the secondary battery 114 or the primary battery 115) to transmit electric power, for example, based on a control signal input from the control circuit 118. Note that the power receiving module 11 can be configured not to include the primary battery 115 and the power transmission circuit 116, and the secondary battery 114 can directly transmit electric power to the main body section 12.

[0103] The sensor 117 is a sensor capable of detecting the presence of a person using the measuring instrument 1, and is, for example, an acceleration sensor or a proximity sensor. If the sensor 117 is an acceleration sensor, the sensor 117 inputs detection data indicating the detected acceleration to the control circuit 118. If the sensor 117 is a proximity sensor, the sensor 117 periodically emits infrared light, and inputs detection data indicating the detection of a person to the control circuit 118 when a person is detected in the vicinity based on the reflected infrared light.

[0104] The sensor 117 can be a person sensor capable of detecting the presence of a person around the measuring instrument 1. The person sensor is, for example, an infrared sensor (thermal ray sensor), an ultrasonic sensor, a microwave sensor, a sound sensor, or an image sensor. The person sensor inputs a detection signal indicating the detection of a person present within a predetermined distance with respect to the measuring instrument 1 to the control circuit 118. The predetermined distance is, for example, a distance within which a wireless electric wave carrying electric power, when transmitted to the measuring instrument 1 by the wireless power transmission device 2, can have some influence on the body of an operator present around the measuring instrument 1.

[0105] The control circuit 118 is a circuit that controls i) charging of the secondary battery 114, ii) switching of the electric power transmitted to the main body section 12 by the electric power transmission circuit 116, and iii) transmission of the beacon signal by the signal transmission section 119. The control circuit 118 includes, for example, an electric circuit for outputting a control signal. The control circuit 118 can include a processor and a memory, and the processor can execute a program stored in the memory to output the control signal. For example, when the remaining capacity of the secondary battery 114 is less than a first threshold value and it is detected based on the signal output from the RF demodulation circuit 112 that wireless power transmission is being performed, the control circuit 118 inputs a control signal to the charging circuit 113 to cause the charging circuit 113 to operate.

[0106] If the remaining capacity of the secondary battery 114 is equal to or higher than a threshold value, the control circuit 118 transmits the electric power of the secondary battery 114 to the electric circuit included in the measuring instrument 1. For example, when the remaining capacity of the secondary battery 114 is equal to or higher than a second threshold value that is smaller than the first threshold value, the control circuit 118 inputs a control signal to the electric power transmission circuit 116 to transmit the electric power output from the secondary battery 114 to the main body section 12.

[0107] On the other hand, when the remaining capacity of the secondary battery 114 is less than the threshold value, the control circuit 118 transmits the electric power of the primary battery 115 to the electric circuit of the measuring instrument 1. For example, when the remaining capacity of the secondary battery 114 is less than the second threshold value, the control circuit 118 inputs a control signal to the electric power transmission circuit 116 to transmit the electric power output from the primary battery 115 to the main body section 12.

[0108] The control circuit 118 operates in this way, thereby making it possible for the main body section 12 to operate while using the electric power stored in the secondary battery 114 as much as possible even when the remaining capacity of the secondary battery 114 is low.

[0109] The control circuit 118 inputs a control signal to the signal transmission section 119 to switch between a state in which the beacon signal is transmitted and a state in which the beacon signal is not transmitted. For example, the control circuit 118 causes the signal transmission section 119 to transmit the beacon signal when the sensor 117 detects that no one is using the measuring instrument 1, and causes the signal transmission section 119 not to transmit the beacon signal when the sensor 117 detects that someone is using the measuring instrument 1. This operation of the control circuit 118 prevents the beacon signal from being transmitted during a period in which someone is using the measuring instrument 1 and the measuring instrument 1 should not receive electric power, in a case in which the wireless power transmission device 2 performs wireless power transmission during reception of the beacon signal. As a result, it is possible to reduce the power consumption of the measuring instrument 1.

[0110] The signal transmitting section 119 is a transmitting section for transmitting a beacon signal, and includes a signal modulation circuit 301 and a light emitting section 302. The signal modulation circuit 301 is a circuit for converting an electrical signal input from the control circuit 118 into an optical signal. The light emitting section 302 is a device that emits light based on an instruction from the signal modulation circuit 301.

[0111] Figure 6 is a schematic view of the power receiving module 11. Figure 6 (a) of FIG. 11 is a perspective view of the power receiving module 11, Figure 6 (b) of FIG. 11 is a front view of the power receiving module 11, and Figure 6 (c) of FIG. 11 is a top view of the power receiving module 11. As Figure 6 As shown in (a) of FIG. 11, the power receiving module 11 includes a first portion PA1 having a shape identical to that of the standard battery B and a second portion PA2 having a shape identical to that of the cover portion C. The first portion PA1 is not limited to having a shape identical to that of the standard battery B, but can have a shape substantially equivalent to that of the standard battery B as long as the first portion PA1 can be accommodated in the accommodation portion ST capable of accommodating the standard battery B. The second portion PA2 is not limited to having a shape identical to that of the cover portion C, but can have a shape substantially equivalent to that of the cover portion C capable of covering the standard battery B in a state where the standard battery B is accommodated in the accommodation portion ST. As one example, the volume of the second portion PA2 can be greater than that of the cover portion C.

[0112] The first portion PA1 and the second portion PA2 have, for example, a cylindrical shape. Since the first portion PA1 is a portion accommodated in the measuring instrument 1 and the second portion PA2 is a cover portion, the diameter of the first portion PA1 is smaller than that of the second portion PA2. Since the power receiving module 11 has such a configuration, the power receiving module 11 can be attached to the measuring instrument 1 instead of the existing button battery B.

[0113] In Figure 6 (b) of FIG. 11, in a front view, Figure 5 The power receiving antenna 110, the charging circuit 113, the secondary battery 114, the primary battery 115, and the power transfer circuit 116 are shown in the power receiving module 11 shown in (a) of FIG. 11. The power receiving antenna 110 is provided, for example, in the second portion PA2. As described above, by providing the power receiving antenna 110 in the second portion PA2 which is a cover portion of the measuring instrument 1, the power receiving antenna 110 is positioned along the surface of the measuring instrument 1, thereby making it easier for the measuring instrument 1 to receive wirelessly transmitted power.

[0114] Charging circuit 113 is provided, for example, in the first part PA1 between the receiving antenna 110 and the secondary battery 114. Secondary battery 114 and primary battery 115 are provided, for example, in the first part PA1 between charging circuit 113 and power transmission circuit 116. Power transmission circuit 116 is positioned, for example, along the surface SU of the first part PA1 opposite to the surface that contacts the second part PA2. As a result, when the receiving module 11 is housed in the receiving portion ST, power can be transmitted from the power transmission circuit 116 to the electrical circuitry of the main body 12.

[0115] The primary battery 115 can be detachably disposed in the power receiving module 11. This allows for a flexible structure in which the primary battery 115 can be omitted when the storage capacity of the secondary battery 114 is high, and the primary battery 115 can be disposed when the storage capacity of the secondary battery 114 is low. For this purpose, an opening for attaching and removing the primary battery 115 can be provided on the side surface of the power receiving module 11.

[0116] like Figure 6 As shown in (c), a slot GR for rotating the power receiving module 11 is provided in the second part PA2 of the power receiving module 11. An operator can attach and remove the power receiving module 11 from the measuring instrument 1 by inserting a flathead screwdriver or fingernail into the slot GR and rotating the power receiving module 11. It should be noted that the measuring instrument 1 can be configured such that the power receiving module 11 can be attached to and removed from the measuring instrument 1 by pinching the side surface of the second part PA2 of the power receiving module 11 with fingers and rotating the power receiving module 11.

[0117] Next, details of the processing performed by the display unit 122 and the controller 124 in the main body 12 will be explained. The controller 124 includes, for example, a CPU for operation by executing a program. The display unit 122, for example, based on instructions from the controller 124, uses power from the primary battery 115 to display a message indicating that the secondary battery 114 needs charging when the remaining capacity of the secondary battery 114 is below a threshold. For example, when the remaining capacity of the secondary battery 114 is below a second threshold, the display unit 122 uses power from the primary battery 115 to display the message "Charging required." Therefore, the operator can temporarily suspend operation and charge the secondary battery 114.

[0118] The controller 124 determines, for example, whether the secondary battery 114 needs charging based on the voltage output from the power receiving module 11, and causes the display unit 122 to display a message indicating that charging is required based on the determination result. Instead of displaying the message on the display, the controller 124 can cause an LED to light up or flash. This also applies to the message display described later.

[0119] If the power receiving module 11 includes a primary battery 115, the controller 124 can obtain a signal from the power receiving module 11 indicating which of the secondary battery 114 and the primary battery 115 is outputting power. In this case, the controller 124 can determine whether the secondary battery 114 needs to be charged if the secondary battery 114 is outputting power.

[0120] It should be noted that at least a portion of the processing described as being performed by control circuit 118 can be performed by controller 124. In this case, controller 124 sends signals to and receives signals from control circuit 118 to issue or receive instructions from control circuit 118.

[0121] [Structure and Operation of Wireless Power Transmission Device 2]

[0122] The structure and operation of wireless power transmission device 2 will be explained. Figure 7 An example of the structure of the wireless power transmission device 2 is shown. The wireless power transmission device 2 includes a signal receiving unit 21, a power transmission unit 22, a memory 23, and a controller 24.

[0123] The signal receiving unit 21 is a receiving unit for receiving beacon signals. The signal receiving unit 21 includes a signal demodulation circuit 212 and multiple light receiving units 211. The light receiving units 211 are devices for receiving optical beacon signals. The signal demodulation circuit 212 is a circuit for converting optical signals input from the light receiving units 211 into electrical signals and inputting the converted electrical signals to the controller 24.

[0124] The power transmission unit 22 is a physical device for wirelessly transmitting power from the wireless power transmission device 2. The power transmission unit 22 includes an RF modulation circuit 221 and multiple power transmission antennas 222. The RF modulation circuit 221 is a circuit for modulating a signal input from the controller 24 into an RF signal and inputting the modulated RF signal to the power transmission antennas 222. The power transmission antennas 222 are physical devices for transmitting RF signals carrying power transmitted from external power transmission devices, etc.

[0125] Memory 23 is a storage medium including ROM and RAM, etc. Memory 23 stores the program executed by controller 24.

[0126] The controller 24 is, for example, a CPU. The controller 24 executes the information processing program stored in the memory 23 to cause the power transmission unit 22 to transmit power when the conditions for power transmission using the power transmission unit 22 are met.

[0127] [Effect of Wireless Power Transmission System S]

[0128] As described above, in the wireless power transfer system S, the power receiving module 11 including the power receiving antenna 110 for receiving the wirelessly transferred power can be attached to the existing surveying instrument 1 in place of the button cell. As a result, the wireless power transfer can be implemented using the existing surveying instrument 1, thereby enabling the operator to continue using the existing surveying instrument 1 as is, while not requiring battery replacement and disposal.

[0129] <Influence of wireless power transfer on human body>

[0130] [Summary]

[0131] When the wireless power transfer is performed to the surveying instrument 1, the power is transmitted in space by being carried on a radio wave, and when the radio wave of high power is radiated to a human, it can have an influence on the human body. Therefore, in the wireless power transfer system S of the present embodiment, the wireless power transfer apparatus 2 transfers power to the surveying instrument 1 in a case where the surveying instrument 1 in a state capable of receiving power is judged by the wireless power transfer apparatus 2 to be located within a predetermined distance with respect to the wireless power transfer apparatus 2 based on the beacon signal received from the surveying instrument 1 and no human is using the surveying instrument 1.

[0132] As a result, the wireless power transfer apparatus 2 can perform the wireless power transfer to the surveying instrument 1 only in a case where the target surveying instrument 1 for the wireless power transfer exists and no human is using the surveying instrument 1, thereby suppressing the influence of the wireless power transfer on the human body. The structure and operation of the surveying instrument 1 and the wireless power transfer apparatus 2 will be described below.

[0133] [Structure and operation of surveying instrument 1]

[0134] Figure 8 Another example of the structure of the surveying instrument 1 is shown. Figure 8 The structure of the surveying instrument 1 shown is different from Figure 4 The structure of the surveying instrument 1 shown is different from

[0135] If the remaining capacity of the secondary battery 114 is low, the surveying instrument 1 prompts the operator using the surveying instrument 1 to charge the secondary battery 114 by displaying that charging using the wireless power transfer is required.

[0136] When the remaining capacity of the secondary battery 114 of the power receiving module 11 is lower than a threshold value, the display section 122 displays that the measuring instrument 1 can receive electric power. When the remaining capacity of the secondary battery 114 is lower than a second threshold value, the display section 122 displays a message such as "Charging is required. Please stop using and move away from the measuring instrument." After displaying the message, the controller 124 of the measuring instrument 1 starts transmitting a beacon signal to start power reception.

[0137] It should be noted that the measuring instrument 1 can display a message prompting charging when the measuring instrument 1 is located at a position where it can be charged by the wireless power transmission device 2. In order to determine whether the measuring instrument 1 is located at a position where it can be charged by the wireless power transmission device 2, the distance identifying section 402 identifies the distance from the wireless power transmission device 2 to the measuring instrument 1. For example, the distance identifying section 402 identifies the distance from the wireless power transmission device 2 to the measuring instrument 1 based on the strength of the beacon signal received by the signal receiving section 120 from the wireless power transmission device 2. When the distance identified by the distance identifying section 402 is equal to or less than a predetermined distance at which the measuring instrument 1 can receive electric power from the wireless power transmission device 2, the display section 122 can display that electric power can be received.

[0138] As described above, the radio waves used for wireless power transmission can have an effect on the human body. Therefore, the measuring instrument 1 transmits a beacon signal to the wireless power transmission device 2 when no person is using the measuring instrument 1, the beacon signal being a power transmission request signal indicating that the measuring instrument 1 is in a state where it can receive electric power, the wireless power transmission device 2 starting power transmission when receiving the beacon signal.

[0139] The signal transmitting section 119 transmits the beacon signal to the wireless power transmission device 2 based on detection by the sensor 117 that no person is using the measuring instrument 1 as one of the conditions, and does not transmit the beacon signal to the wireless power transmission device 2 when the sensor 117 detects that a person is using the measuring instrument 1. If the sensor 117 is an acceleration sensor, the signal transmitting section 119 transmits the beacon signal to the wireless power transmission device 2, for example, when the acceleration indicated by the signal input from the acceleration sensor is lower than a threshold value (for example, zero), and does not transmit the beacon signal to the wireless power transmission device 2 when the acceleration is not zero.

[0140] If the sensor 117 is a proximity sensor, the signal transmitting section 119 transmits the beacon signal to the wireless power transmitting apparatus 2, for example, based on a condition that the signal input from the sensor 117 does not indicate that a person has been detected. The signal transmitting section 119 does not transmit the beacon signal to the wireless power transmitting apparatus 2 when the signal input from the sensor 117 indicates that a person has been detected. It should be noted that when the measuring instrument 1 includes both an acceleration sensor and a proximity sensor as the sensor 117, the signal transmitting section 119 transmits the beacon signal to the wireless power transmitting apparatus 2 based on a condition that the acceleration notified from the acceleration sensor is zero and that the sensor 117 does not detect a person.

[0141] As described above, the signal transmitting section 119 transmits the beacon signal to the wireless power transmitting apparatus 2 based on a condition that the sensor 117 detects that no person is using the measuring instrument 1, whereby in a case where the wireless power transmitting apparatus 2 performs wireless power transmission during reception of the beacon signal, transmission of the beacon signal during a period when a person is using the measuring instrument 1 and the measuring instrument 1 should not receive power is prevented. As a result, it is possible to prevent the influence of wireless power transmission on the human body.

[0142] Even when no person is using the measuring instrument 1, if an operator is present around the measuring instrument 1, transmission of a wireless electric wave carrying power from the wireless power transmitting apparatus 2 to the measuring instrument 1 can have an influence on the human body of the operator. Therefore, if the sensor 117 is a person detection sensor, the signal transmitting section 119 can transmit the beacon signal to the wireless power transmitting apparatus 2 under a condition that the person detection sensor does not detect a person within a predetermined distance with respect to the measuring instrument 1.

[0143] The signal transmitting section 119 can transmit the beacon signal as a power transmission request signal to the wireless power transmitting apparatus 2 in a case where i) the acceleration notified from the acceleration sensor is zero, and ii) no detection signal indicating that a person is detected within a predetermined distance with respect to the measuring instrument 1 is input from the control circuit 118.

[0144] On the other hand, the signal transmitting section 119 can be configured to not transmit the beacon signal to the wireless power transmitting apparatus 2 in a case where the person sensor detects a person located within a predetermined distance with respect to the measuring instrument 1. The signal transmitting section 119 can be configured to not transmit the beacon signal as a power transmission request signal to the wireless power transmitting apparatus 2 in a case where i) the acceleration notified from the acceleration sensor is not zero, or ii) a detection signal indicating that a person is detected within a predetermined distance with respect to the measuring instrument 1 is input from the control circuit 118.

[0145] As described above, the signal transmitting section 119 does not transmit the beacon signal as the power transmission request signal to the wireless power transmission device 2 even when there is a person around the measuring instrument 1, even if the person is not using the measuring instrument 1. This makes it possible to prevent the wireless power transmission device 2 from transmitting the wireless electric wave carrying the electric power to the measuring instrument 1 when there is a person around the measuring instrument 1. As a result, it is possible to suppress the influence of the wireless power transmission on the human body.

[0146] The signal transmitting section 119 can transmit the beacon signal on the condition that the remaining capacity of the secondary battery 114 is lower than a threshold value. For example, the signal transmitting section 119 can transmit the beacon signal when it is detected that no person is using the measuring instrument 1 and the remaining capacity of the secondary battery 114 is lower than the threshold value. The measuring instrument 1 transmits the beacon signal only when the wireless power transmission should be performed, thereby reducing the power consumption of the measuring instrument 1.

[0147] The signal transmitting section 119 can transmit the beacon signal indicating that the measuring instrument 1 is not in a state capable of receiving the electric power or that a person is using the measuring instrument 1 when it is detected that a person is using the measuring instrument 1. In this case, the wireless power transmission device 2 performs the wireless power transmission on the condition that the wireless power transmission device 2 does not receive the beacon signal, thereby preventing the wireless power transmission from having an influence on the human body.

[0148] In the above description, it is exemplified that the signal transmitting section 119 transmits the beacon signal when the distance identified by the distance identifying section 402 is equal to or smaller than the distance at which the measuring instrument 1 can receive the electric power from the wireless power transmission device 2, but the signal transmitting section 119 can transmit the beacon signal in response to an operation by the operator for receiving the electric power. Specifically, the signal transmitting section 119 can transmit the beacon signal indicating that the measuring instrument 1 is in a state capable of receiving the electric power to the wireless power transmission device 2 in response to the power receiving operation by the operation section 121 for starting the power reception. As described above, since the measuring instrument 1 transmits the beacon signal every several seconds, the signal transmitting section 119 can use, for example, the beacon signal transmitted after the operation for receiving the electric power is performed, as the beacon signal indicating that the measuring instrument 1 is in a state capable of receiving the electric power. By making the manual power transmission instruction possible in this way, the measuring instrument 1 becomes more user-friendly to the operator.

[0149] It should be noted that the measuring instrument 1 does not need to receive the electric power from the wireless power transmission device 2 in the case where the power receiving module 11 is not attached to the measuring instrument 1 and the measuring instrument 1 is operated with the electric power transmitted by the standard battery B. Therefore, in order to make the operation changeable depending on whether the power receiving module 11 is attached to the measuring instrument 1 or not, the judging section 401 judges which of the standardized standard battery B and the power receiving module 11 is housed in the measuring instrument 1.

[0150] In order for the determination section 401 to be able to determine which of the standard battery B and the power-receiving module 11 is housed in the measuring instrument 1, the second portion PA2 that is the cover-side portion of the power-receiving module 11 has, for example, a different configuration from that of the cover portion C that covers the standard battery B while still serving as a battery cover. Specifically, a switch SW is provided in the housing portion ST of the measuring instrument 1, and the second portion PA2 is configured to press the switch SW when the second portion PA2 is housed in the housing portion ST. In other words, a switch SW is provided in the housing portion ST of the measuring instrument 1 that cannot be pressed with the cover portion C used for the standard battery B but can be pressed with the second portion PA2 of the power-receiving module 11. Thus, the determination section 401 can determine that the standard battery B is housed in the measuring instrument 1 when the switch SW is not pressed, and that the power-receiving module 11 is housed in the measuring instrument 1 when the switch SW is pressed.

[0151] In the case where the determination section 401 determines that the standard battery B is housed in the measuring instrument 1, the measuring instrument 1 operates with the power of the standard battery B, and thus does not display a message prompting charging and does not transmit a beacon signal as a power transfer request signal to the wireless power transfer apparatus 2. On the other hand, in the case where the determination section 401 determines that the power-receiving module 11 is housed in the measuring instrument 1, the measuring instrument 1 operates with the power charged in the secondary battery 114 of the power-receiving module 11, and thus displays a message prompting charging and transmits a beacon signal as a power transfer request signal to the wireless power transfer apparatus 2.

[0152] [Structure and operation of wireless power transfer apparatus 2]

[0153] Figure 9 Another example of the structure of the wireless power transfer apparatus 2 is shown. Figure 9 The structure of the wireless power transfer apparatus 2 shown is different from Figure 7 The structure of the wireless power transfer apparatus 2 shown is different in that i) the controller 24 includes a position identification section 241 and a power transfer controller 245 as a specific structure, and ii) the wireless power transfer apparatus 2 includes a signal transmission section 25.

[0154] The signal reception section 21 receives a beacon signal (e.g., a power transfer request signal) from the measuring instrument 1 that indicates a state of the measuring instrument 1. The state of the measuring instrument 1 is, for example, i) a state in which the measuring instrument 1 needs charging and is located within a predetermined distance relative to the wireless power transfer apparatus 2, and no one is in the vicinity of the measuring instrument 1, or ii) a state in which the measuring instrument 1 has received an operation input for starting power reception.

[0155] The memory 23 stores power transferable region data for indicating a power transferable region in which power can be wirelessly transferred. The power transferable region is defined by a direction in which the power transferable region is present and a distance to the power transferable region, with the position of the wireless power transfer device 2 as a reference.

[0156] The position recognition section 241 recognizes the position of the measuring instrument 1 based on the beacon signal received by the signal reception section 21 from the measuring instrument 1. The position recognition section 241, for example, recognizes the direction in which the measuring instrument 1 is present and the distance to the measuring instrument 1, with the position of the wireless power transfer device 2 as a reference, based on the direction and intensity of the beacon signal received by the signal reception section 21 from the measuring instrument 1, as the relative position of the measuring instrument 1.

[0157] The position recognition section 241, for example, recognizes the distance from the wireless power transfer device 2 to the measuring instrument 1 based on the intensity of the beacon signal received by the signal reception section 21. Further, the position recognition section 241 recognizes the direction of the measuring instrument 1 with respect to the wireless power transfer device 2 based on the difference in timing at which the beacon signal is received by each of the plurality of light reception sections 211 included in the signal reception section 21.

[0158] Specifically, if the plurality of light reception sections 211 simultaneously receive the beacon signal, the position recognition section 241 recognizes that the measuring instrument 1 is on a middle line extending in a direction perpendicular to a straight line connecting the plurality of light reception sections 211 from a midpoint between the plurality of light reception sections 211. If the timing at which one light reception section 211 receives the beacon signal is earlier than the timing at which another light reception section 211 receives the beacon signal, the position recognition section 241 recognizes that the measuring instrument 1 is located in a direction closer to the one light reception section 211 than the middle line.

[0159] The power transmission controller 245 causes the power transmission section 22 to transmit power in a case where it is determined based on the beacon signal received by the signal reception section 21 from the measuring instrument 1 that the measuring instrument 1 is located within a predetermined distance with respect to the wireless power transfer device 2 and that no person is using the measuring instrument 1. The power transmission controller 245, for example, causes the power transmission section 22 to transmit power in a case where the signal reception section 21 is receiving the beacon signal and it is determined based on the intensity of the received beacon signal that the measuring instrument 1 is within a distance in which the measuring instrument 1 can receive power from the wireless power transfer device 2.

[0160] As described above, the wireless power transfer device 2 wirelessly transfers power to the measuring instrument 1 when the measuring instrument 1 is within a distance in which the wireless power transfer device 2 can wirelessly transfer power and no person is using the measuring instrument 1, thereby suppressing the influence of wireless power transmission on the human body. However, even in this case, the wireless power transfer device 2 is not preferable to perform wireless power transfer in a case where the measuring instrument 1 is located in an area normally occupied by a person.

[0161] Therefore, even if the measuring instrument 1 is located within the predetermined distance with respect to the wireless power transmission apparatus 2 and no person is using the measuring instrument 1, the power transmission controller 245 does not cause the power transmission unit 22 to transmit power in a case where the measuring instrument 1 is located outside the power-transmittable region where power can be wirelessly transmitted by the wireless power transmission apparatus 2. For example, in a case where the relative position of the measuring instrument 1 with respect to the position of the wireless power transmission apparatus 2, which is recognized by the position recognition unit 241, is located outside the power-transmittable region with respect to the position of the wireless power transmission apparatus 2 as indicated by the power-transmittable region data stored in the storage 23, the power transmission controller 245 does not cause the power transmission unit 22 to transmit power. In this way, the power transmission controller 245 causes the power transmission unit 22 not to transmit power in a case where the measuring instrument 1 is located in a region normally occupied by a person, thereby preventing the power transmission unit 22 from transmitting power in a state where the possibility that a person is in the vicinity of the measuring instrument 1 is high.

[0162] Even in a case where the measuring instrument 1 is located within a distance where power can be wirelessly transmitted by the wireless power transmission apparatus 2 and no person is using the measuring instrument 1, it is not preferable for the wireless power transmission apparatus 2 to initiate wireless power transmission to the measuring instrument 1 immediately after the operator stops using the measuring instrument 1, because it is possible that the operator is in the vicinity of the measuring instrument 1, which can result in, for example, wireless electric waves carrying power being radiated onto the operator.

[0163] Therefore, even if it is determined that the measuring instrument 1 is located within the predetermined distance with respect to the wireless power transmission apparatus 2 and no person is using the measuring instrument 1, the power transmission controller 245 does not cause the power transmission unit 22 to transmit power within a predetermined time after the signal reception unit 21 receives the beacon signal from the measuring instrument 1. The power transmission controller 245, for example, prevents the power transmission unit 22 from transmitting power during a second time period after the beacon signal is received for the first time after a first time period has elapsed in which no beacon signal is received. The power transmission controller 245, for example, causes the power transmission unit 22 to start power transmission after a time required for the operator using the measuring instrument 1 to move away from the measuring instrument 1 by at least a predetermined distance, for example, one minute, has elapsed since the signal reception unit 21 receives the beacon signal indicating that the measuring instrument 1 is in a state where power can be received.

[0164] This prevents the wireless power transmission apparatus 2 from wirelessly transmitting power to the measuring instrument 1 before the operator moves away from the vicinity of the measuring instrument 1 after the operator stops using the measuring instrument 1, thereby ensuring the safety of the operator.

[0165] [Processing in the wireless power transmission apparatus 2]

[0166] The processing performed by the wireless power transmission apparatus 2 will be described. Figure 10 is a flowchart illustrating the processing performed by the wireless power transmission apparatus 2.

[0167] The power transmission controller 245 determines whether the signal receiving section 21 receives the beacon signal from the measuring instrument 1 (S1). If the power transmission controller 245 determines that the beacon signal is not received (S1: "No"), the process proceeds to step S6.

[0168] On the other hand, if the power transmission controller 245 determines that the beacon signal is received (S1: "Yes"), the power transmission controller 245 determines whether the measuring instrument 1 is located within a distance from the wireless power transmission apparatus 2 within which the measuring instrument 1 can receive power (S2). If the power transmission controller 245 determines that the measuring instrument 1 is not located within the distance from the wireless power transmission apparatus 2 within which the measuring instrument 1 can receive power (S2: "No"), the process proceeds to step S6.

[0169] On the other hand, if the power transmission controller 245 determines that the measuring instrument 1 is located within the distance from the wireless power transmission apparatus 2 within which the measuring instrument 1 can receive power (S2: "Yes"), the power transmission controller 245 determines whether the measuring instrument 1 is located within a power-transmittable region within which power can be wirelessly transmitted (S3). If the power transmission controller 245 determines that the measuring instrument 1 is not located within the power-transmittable region (S3: "No"), the process proceeds to step S6.

[0170] On the other hand, if the power transmission controller 245 determines that the measuring instrument 1 is located within the power-transmittable region (S3: "Yes"), the power transmission controller 245 determines whether a predetermined time has elapsed since the beacon signal was received (S4). If the power transmission controller 245 determines that the predetermined time has not elapsed since the beacon signal was received (S4: "No"), the process proceeds to step S6.

[0171] On the other hand, if the power transmission controller 245 determines that the predetermined time has elapsed since the beacon signal was received (S4: "Yes"), the power transmission controller 245 causes the power transmission section 22 to transmit power (S5).

[0172] If the power transmission controller 245 determines "No" in step S1, S2, S3, or S4, the power transmission controller 245 causes the power transmission section 22 not to transmit power (S6).

[0173] [Modified Example]

[0174] In the above-described example, the signal transmitting section 119 transmits a beacon signal to the wireless power transmitting apparatus 2 indicating the presence or absence of a person using the measuring instrument 1 detected by the sensor 117, but the signal transmitting section 119 can transmit a beacon signal to the wireless power transmitting apparatus 2 indicating the presence or absence of a person using the measuring instrument 1 detected by the sensor 117. That is, the signal transmitting section 119 can continuously transmit a beacon signal to the wireless power transmitting apparatus 2 regardless of whether or not a person is using the measuring instrument 1. In this case, the transmitted beacon signal includes information for identifying the presence or absence of a person using the measuring instrument 1.

[0175] In this case, the power feeding controller 245 of the wireless power transmitting apparatus 2 causes the power feeding section 22 to transmit power in a case where i) the measuring instrument 1 is judged to be located within a predetermined distance with respect to the wireless power transmitting apparatus 2 based on the strength of the beacon signal received by the signal receiving section 21 from the measuring instrument 1, and ii) the beacon signal received by the signal receiving section 21 from the measuring instrument 1 is judged to include information indicating that no person is using the measuring instrument 1.

[0176] In addition, in a case where the sensor 117 is a person sensor, the signal transmitting section 119 can transmit a beacon signal to the wireless power transmitting apparatus 2 indicating the presence or absence of a person around the measuring instrument 1 as detected by the person sensor. That is, the signal transmitting section 119 can continuously transmit a beacon signal to the wireless power transmitting apparatus 2 regardless of whether or not a person is around the measuring instrument 1. In this case, the transmitted beacon signal includes information for identifying the presence or absence of a person around the measuring instrument 1.

[0177] The power feeding controller 245 of the wireless power transmitting apparatus 2 that has received the beacon signal causes the power feeding section 22 to transmit power in a case where i) the measuring instrument 1 is judged to be located within a predetermined distance with respect to the wireless power transmitting apparatus 2 based on the strength of the received beacon signal, and ii) the received beacon signal is judged to include information indicating that no person is using the measuring instrument 1 and information indicating that no person is around the measuring instrument 1.

[0178] [Effects of the wireless power transmission system S]

[0179] As described above, in the wireless power transmission system S, the wireless power transmitting apparatus 2 can transmit power to the measuring instrument 1 in a case where the power feeding controller 245 judges that the measuring instrument 1 is located within a predetermined distance with respect to the wireless power transmitting apparatus 2 and that no person is using the measuring instrument 1 based on the beacon signal received by the wireless power transmitting apparatus 2 from the measuring instrument 1. This makes it possible to suppress the influence of wireless power transmission on the human body of an operator.

[0180] Further, in the wireless power transfer system S, in a case where the measuring instrument 1 is in an area normally occupied by a person, the power transmission controller 245 can prevent the power transmission unit 22 from transmitting power. This prevents the power transmission unit 22 from transmitting power in a state where the measuring instrument 1 is placed at a place where the presence of a person is likely, thereby enhancing safety.

[0181] [Summary]

[0182] [Summary]

[0183] An operator performs work in a state where the measuring instrument 1 is held in his / her hand, and thus the orientation of the measuring instrument 1 can change. Further, in a case where the measuring instrument 1 is placed on a desk or a floor, the orientation of the measuring instrument 1 can be different before and after work. Depending on the orientation of the measuring instrument 1, the distance between the wireless power transfer apparatus 2 and the power receiving antenna of the measuring instrument 1 can increase, or the power receiving antenna can be hidden behind the main body 12 of the measuring instrument 1 from the perspective of the wireless power transfer apparatus 2. As a result, the measuring instrument 1 can have difficulty receiving power transferred from the wireless power transfer apparatus 2, and the power transfer efficiency can decrease.

[0184] Therefore, the measuring instrument 1 can include a plurality of power receiving antennas 110. The wireless power transfer apparatus 2 identifies the positions of the respective power receiving antennas 110 based on posture data indicating the posture of the measuring instrument 1 received from the measuring instrument 1, and causes the power transmission antenna 222 to transmit power to the power receiving antenna 110 among the identified power receiving antennas 110 that can receive the largest amount of power, thereby improving the power transfer efficiency. The structure and operation of the measuring instrument 1 and the wireless power transfer apparatus 2 will be described below.

[0185] [Structure and operation of measuring instrument 1]

[0186] Figure 11 Another example of the structure of the measuring instrument 1 is shown. Figure 11 The measuring instrument 1 shown in Figure 4 The measuring instrument 1 shown in Figure 11 The measuring instrument 1 shown in

[0187] In Figure 11 the plurality of power receiving antennas 110 are shown outside the main body 12, but the plurality of power receiving antennas 110 can be built into the main body 12. Figure 11 The power receiving module 11 shown can include some of the plurality of power receiving antennas 110, but can be configured not to include the power receiving antenna 110.

[0188] The plurality of power receiving antennas 110 are, for example, pattern antennas coupled to the power receiving module 11 by Q-matching. The power receiving module 11 includes a selection circuit for selecting a power receiving antenna 110 that has received the strongest electric power and that achieves the highest power transfer efficiency among the plurality of power receiving antennas 110. The selection circuit selects the power receiving antenna 110 to be used for receiving electric power, for example, on the basis of Figure 8 the control of the control circuit 118 shown.

[0189] A plurality of display devices 125 are provided to correspond to the plurality of power receiving antennas 110, respectively. Among the plurality of display devices 125, the display device 125 corresponding to the power receiving antenna 110 that is receiving electric power transmitted by the power transmitting antenna 222 displays that electric power is being received. The display device 125 is, for example, an LED. The controller 124 compares the electric power received from the power receiving antenna 110 with a threshold value, and causes the LED corresponding to the power receiving antenna 110 that receives electric power equal to or higher than the threshold value in amount of electric power to be lit up.

[0190] Thus, the display device 125 corresponding to the power receiving antenna 110 that is receiving electric power indicates that electric power is being received, thereby enabling the operator to grasp that the measuring instrument 1 is receiving electric power and which power receiving antenna 110 is receiving electric power.

[0191] The posture detection section 126 includes, for example, a gyro sensor, and detects the posture of the measuring instrument 1 by measuring the angular velocity of the measuring instrument 1. The posture of the measuring instrument 1 is represented, for example, by a roll angle, a pitch angle, and a yaw angle from an initial posture in which the measuring instrument 1 is placed on the upper surface of the wireless power transfer apparatus 2 at a predetermined angle. As one example, the controller 124 notifies the posture detection section 126 that the operation for setting the initial posture has been performed on the operation section 121, and the posture detection section 126 inputs data for indicating the roll angle, the pitch angle, and the yaw angle from the posture of the posture detection section 126 at the time of receiving the notification to the controller 124.

[0192] The posture detection section 126 transmits the posture data to the wireless power transfer apparatus 2 via the power receiving module 11. Specifically, the signal transmission section 119 included in the power receiving module 11 transmits a beacon signal including information for indicating the posture detected by the posture detection section 126. After the signal transmission section 119 transmits the beacon signal, any of the plurality of power receiving antennas 110 receives electric power from the wireless power transfer apparatus 2.

[0193] As will be described later in detail, the wireless power transfer apparatus 2 that has received the beacon signal identifies the power receiving antenna 110 to be a power transmission target on the basis of the posture of the measuring instrument 1 indicated by the received beacon signal. The identified power receiving antenna 110 receives electric power transferred from the wireless power transfer apparatus 2.

[0194] [Structure and operation of wireless power transmission apparatus 2]

[0195] The structure and operation of the wireless power transmission apparatus 2 will be explained. Figure 12 Another example of the structure of the wireless power transmission apparatus 2 is shown. Figure 12 The structure of the wireless power transmission apparatus 2 shown is different from the structure of the wireless power transmission apparatus 2 shown in FIG. 1 in that the controller 24 includes a measurement instrument identification section 242, a power receiving position identification section 243, a power transmission target identification section 244, and a power transmission controller 245 as a specific structure. Figure 7 The structure of the wireless power transmission apparatus 2 shown is different from the structure of the wireless power transmission apparatus 2 shown in FIG. 1 in that the controller 24 includes a measurement instrument identification section 242, a power receiving position identification section 243, a power transmission target identification section 244, and a power transmission controller 245 as a specific structure.

[0196] The memory 23 stores shape data for indicating the shape of the measurement instrument 1. The shape of the measurement instrument 1 is, for example, the three-dimensional shape of the main body section of the measurement instrument 1. As will be explained later in detail, the shape data is used by the wireless power transmission apparatus 2 to identify the position of the power receiving antenna 110 that is not hidden behind the main body section of the measurement instrument 1. In addition, the memory 23 stores position relationship data for indicating the positional relationship between the plurality of power receiving antennas 110 in the measurement instrument 1. The position relationship data is, for example, data for indicating the coordinates of the plurality of power receiving antennas 110 in a three-dimensional coordinate space having the signal transmission section 119 of the power receiving module 11 as the origin.

[0197] The measurement instrument identification section 242 identifies the position of the signal transmission section 119 in the measurement instrument 1 that transmits the beacon signal relative to the wireless power transmission apparatus 2 based on the beacon signal received by the signal reception section 21. The measurement instrument identification section 242 identifies, for example, the distance from the wireless power transmission apparatus 2 to the signal transmission section 119 of the measurement instrument 1 based on the strength of the beacon signal received by the signal reception section 21. In addition, the measurement instrument identification section 242 identifies, for example, the direction of the signal transmission section 119 in the measurement instrument 1 relative to the wireless power transmission apparatus 2 based on the difference in the timing at which the beacon signal is received by each of the plurality of light receiving sections 211 included in the signal reception section 21.

[0198] Specifically, in the case where the beacon signal is received by the plurality of light receiving sections 211 at the same time, the measurement instrument identification section 242 identifies that the signal transmission section 119 of the measurement instrument 1 is on an intermediate line that extends in a direction perpendicular to a straight line connecting the plurality of light receiving sections 211 from the midpoint between the plurality of light receiving sections 211. In the case where the timing at which the beacon signal is received by one light receiving section 211 is earlier than the timing at which the beacon signal is received by another light receiving section 211, the measurement instrument identification section 242 identifies that the signal transmission section 119 of the measurement instrument 1 is located in a direction closer to the one light receiving section 211 than the intermediate line.

[0199] The measurement instrument identification unit 242 identifies the posture of the measurement instrument 1 on the basis of the beacon signal received by the signal receiving unit 21. For example, the measurement instrument identification unit 242 identifies the orientation of the measurement instrument 1 in the device coordinate system with the position of the wireless power transfer apparatus 2 as the reference on the basis of the information for indicating the posture of the measurement instrument 1 included in the beacon signal received by the signal receiving unit 21.

[0200] The power reception position identification unit 243 identifies the positions of the plurality of power reception antennas 110 on the basis of i) the positional relationship data for indicating the positional relationship in the measurement instrument 1 between the signal transmitting unit 119 and each of the plurality of power reception antennas 110, ii) the position of the signal transmitting unit 119 identified by the measurement instrument identification unit 242, and iii) the posture of the measurement instrument 1. For example, the power reception position identification unit 243 identifies the positions of the plurality of power reception antennas 110 each time the signal receiving unit 21 receives the beacon signal including the information for indicating the posture. The method used by the power reception position identification unit 243 to identify the positions of the plurality of power reception antennas 110 will be described below.

[0201] First, the power reception position identification unit 243 generates a plurality of correction vectors by correcting a plurality of vectors for indicating the positions of the plurality of power reception antennas 110 relative to the position of the signal transmitting unit 119 in the measurement instrument coordinate system with the position of the measurement instrument 1 as the reference on the basis of the posture of the measurement instrument 1. The plurality of correction vectors are a plurality of vectors for indicating the positions of the plurality of power reception antennas 110 relative to the position of the signal transmitting unit 119 in the device coordinate system with the position of the wireless power transfer apparatus 2 as the reference.

[0202] Figure 13 An example of the generation of the correction vectors is shown. Figure 13 The device coordinate system shown is a three-dimensional coordinate system defined by three axes (DX, DY, and DZ) with an arbitrary point (DO) in the wireless power transfer apparatus 2 as the origin. It is assumed that the posture of the measurement instrument 1 after the posture change is tilted by A degrees in the device coordinate system relative to the posture before the posture change. In this case, as shown, Figure 13 As shown, the power reception position identification unit 243 generates the correction vectors (indicated by dotted arrows) by rotating the pre-correction vectors (indicated by solid arrows) for indicating the positions Pa of the plurality of power reception antennas 110 relative to the position Pb of the signal transmitting unit 119 in the measurement instrument coordinate system by A degrees.

[0203] Next, the power reception position identification unit 243 identifies the positions of the plurality of power reception antennas 110 each by adding each of the plurality of correction vectors to the position of the signal transmitting unit 119 identified by the measurement instrument identification unit 242 in the device coordinate system with the position of the wireless power transfer apparatus 2 as the reference.

[0204] Figure 14 An example of identifying the positions of the plurality of power receiving antennas 110 is shown. As shown, the power receiving position identifying section 243 adds a plurality of correction vectors (indicated by dotted arrows) to the position DPb of the signal transmitting section 119 identified by the surveying instrument identifying section 242 in the device coordinate system to identify the position DPa of each of the plurality of power receiving antennas 110 in the device coordinate system. Figure 14

[0205] In this way, the power receiving position identifying section 243 identifies i) the direction in which each of the plurality of power receiving antennas 110 is located after the change in the posture of the surveying instrument 1 and ii) the distance to each of the plurality of power receiving antennas 110 after the change in the posture of the surveying instrument 1, with reference to the wireless power transmission apparatus 2.

[0206] In the case where the power receiving position identifying section 243 identifies the positions of the plurality of power receiving antennas 110 each time the signal receiving section 21 receives a beacon signal containing information indicating a posture, the power receiving position identifying section 243 can identify the positions of the plurality of power receiving antennas 110 even when the posture of the surveying instrument 1 has not changed, which potentially increases the processing load of the wireless power transmission apparatus 2. Therefore, the power receiving position identifying section 243 can identify the positions of the plurality of power receiving antennas 110 based on the posture of the surveying instrument 1 after a change in the posture in response to the surveying instrument 1 detecting a change in the posture of the surveying instrument 1. For example, the power receiving position identifying section 243 identifies the positions of the plurality of power receiving antennas 110 when a change in the posture indicated by the posture information is identified, and does not identify the positions of the plurality of power receiving antennas 110 during a period in which there is no change in the posture.

[0207] In this way, the power receiving position identifying section 243 re-identifies the positions of the plurality of power receiving antennas 110 when the posture of the surveying instrument 1 changes, so that the processing load of the wireless power transmission apparatus 2 is reduced, making it less likely that a processing delay will occur in the wireless power transmission apparatus 2.

[0208] The power transmission target identifying section 244 identifies a power receiving antenna 110 that can receive the largest amount of power transmitted by the power transmission antenna 222 as a power transmission target from among the plurality of power receiving antennas 110 based on the positions of the plurality of power receiving antennas 110 identified by the power receiving position identifying section 243. For example, the power transmission target identifying section 244 identifies a power receiving antenna 110 that is closest to the power transmission antenna 222 from among the plurality of power receiving antennas 110 as a power transmission target.

[0209] ​In this way, the power transmission target identifying section 244 identifies the power receiving antenna 110 that is the shortest distance from the power transmission antenna 222 as the power transmission target, and thus wireless power transfer can be efficiently performed. However, from the perspective of the power transmission antenna 222, the power receiving antenna 110 that is the shortest distance from the power transmission antenna 222 can be hidden behind the main body section 12 of the measuring instrument 1. In this case, even in the case where the power transmission antenna 222 transmits power to the power receiving antenna 110 at the shortest distance, the main body section 12 blocks the power, and thus the power transmission efficiency cannot be considered to be optimal.

[0210] Therefore, the power transmission target identifying section 244 identifies the power receiving antenna 110, for which the main body section 12 of the measuring instrument 1 is not located on a straight line connecting the power transmission antenna 222 and the power receiving antenna 110, as the power transmission target by referring to shape data indicating the shape of the measuring instrument 1. For example, the power transmission target identifying section 244 sequentially determines whether the main body section 12 of the measuring instrument 1 is located on a straight line connecting the power transmission antenna 222 and the power receiving antenna 110 from the power receiving antenna 110 closest to the power transmission antenna 222, and identifies the first power receiving antenna 110 for which the main body section 12 is determined not to be located on the straight line as the power transmission target. In this way, the power transmission target identifying section 244 identifies the power receiving antenna 110 that is not hidden behind the main body section 12 of the measuring instrument 1 as the power transmission target, and thus wireless power transfer can be efficiently performed.

[0211] The power transmission controller 245 causes the power transmission antenna 222 to transmit power to the power receiving antenna 110 identified by the power transmission target identifying section 244. The power transmission controller 245 causes the power transmission section 22 to transmit power toward the power receiving antenna 110 to be powered, for example, by using a plurality of power transmission antennas 222 to perform beamforming, causing radio waves to be emitted in the direction in which the power receiving antenna 110 identified by the power transmission target identifying section 244 is located. The power transmission controller 245 can i) select a power transmission antenna 222 suitable for power transmission to the power receiving antenna 110 identified by the power transmission target identifying section 244, or ii) change the orientation of the power transmission antenna 222 to face the power receiving antenna 110 identified by the power transmission target identifying section 244.

[0212] It should be noted that in a case where there are multiple types of measuring instruments 1 of which the wireless power transfer apparatus 2 can transfer power, the wireless power transfer apparatus 2 cannot identify the positions of the multiple power receiving antennas 110 by recognizing the posture of the measuring instrument 1 alone. Therefore, the memory 123 can store position relationship data for indicating the positions of the multiple power receiving antennas 110 in the measuring instrument 1, and the signal transmitting section 119 in the measuring instrument 1 can transmit a beacon signal including the position relationship data to the wireless power transfer apparatus 2. The signal receiving section 21 in the wireless power transfer apparatus 2 receives the beacon signal including the position relationship data. The power receiving position identifying section 243 identifies the respective positions of the multiple power receiving antennas 110 based on the position relationship data included in the received beacon signal.

[0213] In a case where the wireless power transfer apparatus 2 stores the position relationship data in association with the type of the measuring instrument 1, the memory 123 can store type data for indicating the type of the measuring instrument 1, and the signal transmitting section 119 in the measuring instrument 1 can transmit a beacon signal including the type data to the wireless power transfer apparatus 2. The signal receiving section 21 in the wireless power transfer apparatus 2 receives the beacon signal including the type data. The power receiving position identifying section 243 identifies the respective positions of the multiple power receiving antennas 110 based on the position relationship data corresponding to the type data included in the received beacon signal.

[0214] Further, if the measuring instrument 1 that can be powered by the wireless power transfer apparatus 2 has multiple types of shapes, the power transfer target identifying section 244 cannot identify the power receiving antenna 110 that is not hidden behind the main body section 12 of the measuring instrument 1 by recognizing the posture of the measuring instrument 1 alone. Therefore, the memory 123 can store shape data for indicating the shape of the measuring instrument 1, and the signal transmitting section 119 in the measuring instrument 1 can transmit a beacon signal including the shape data to the wireless power transfer apparatus 2. The power transfer target identifying section 244 identifies the power receiving antenna 110 that is not hidden behind the main body section 12 of the measuring instrument 1 by referring to the shape data included in the received beacon signal.

[0215] [Processing in the wireless power transfer apparatus 2]

[0216] The processing performed by the wireless power transfer apparatus 2 will be described. Figure 15 is a flowchart illustrating the processing performed by the wireless power transfer apparatus 2.

[0217] The signal receiving section 21 receives a beacon signal for indicating the posture of the measuring instrument 1 from the measuring instrument 1, where the posture of the measuring instrument 1 is detected by a gyro sensor included in the measuring instrument 1 for measuring the angular velocity of the measuring instrument 1. The measuring instrument identifying section 242 identifies the posture of the measuring instrument 1 based on the beacon signal received by the signal receiving section 21 (S11).

[0218] The measuring instrument identifying section 242 identifies the position of the measuring instrument 1 (the position of the signal transmitting section 119) based on the strength and direction of the beacon signal received by the signal receiving section 21 (S12).

[0219] The power receiving position identifying section 243 identifies the positions of the plurality of power receiving antennas 110 based on i) position relationship data for indicating the positional relationship between the signal transmitting section 119 and each of the plurality of power receiving antennas 110 in the measuring instrument 1, ii) the posture of the measuring instrument 1 identified by the measuring instrument identifying section 242, and iii) the position of the signal transmitting section 119 identified by the measuring instrument identifying section 242 (S13).

[0220] The power transmitting target identifying section 244 identifies the power receiving antenna 110 having the shortest distance to the power transmitting antenna 222 among the plurality of power receiving antennas 110 as the power transmitting target (S14).

[0221] The power transmitting target identifying section 244 determines whether the main body 12 of the measuring instrument 1 is located on a straight line connecting the power transmitting antenna 222 and the identified power receiving antenna 110 (that is, whether the identified power receiving antenna 110 is hidden behind the main body 12 of the measuring instrument 1) (S15).

[0222] If the power transmitting target identifying section 244 determines that the main body 12 of the measuring instrument 1 is located on the straight line connecting the power transmitting antenna 222 and the identified power receiving antenna 110 (the identified power receiving antenna 110 is hidden behind the main body 12 of the measuring instrument 1) (S15: "Yes"), the power transmitting target identifying section 244 identifies the power receiving antenna 110 having the shortest distance to the power transmitting antenna 222 among the power receiving antennas 110 other than the already identified power receiving antenna 110 as the power transmitting target (S14).

[0223] Then, the power transmitting target identifying section 244 again determines whether the main body 12 of the measuring instrument 1 is located on the straight line connecting the power transmitting antenna 222 and the identified power receiving antenna 110 (S15). In this way, the power transmitting target identifying section 244 sequentially determines whether the main body 12 of the measuring instrument 1 is located on the straight line connecting the power transmitting antenna 222 and the power receiving antenna 110 from the power receiving antenna 110 closest to the power transmitting antenna 222, and in the case where it is determined that the main body 12 is not located on the straight line, proceeds to the next step S16.

[0224] If the power transmission target identification unit 244 determines that the main body 12 of the measuring instrument 1 is not located on a straight line connecting the power transmission antenna 222 and the identified power reception antenna 110 (the identified power reception antenna 110 is not hidden behind the main body 12 of the measuring instrument 1) (S15: "No"), the power transmission controller 245 causes the power transmission antenna 222 to transmit electric power to the power reception antenna 110 identified by the power transmission target identification unit 244 (S16).

[0225] The controller 24 of the wireless power transmission apparatus 2 determines whether charging of the secondary battery 114 is completed based on the beacon signal received by the signal reception unit 21 (S17). If the controller 24 determines that charging of the secondary battery 114 is not completed (S17: "No"), the processing of step S11 is performed again. On the other hand, if the controller 24 determines that charging of the secondary battery 114 is completed (S17: "Yes"), the processing ends.

[0226] The measuring instrument identification unit 242, the power reception position identification unit 243, the power transmission target identification unit 244, and the power transmission controller 245 continuously perform the processing from S11 to S17 until the signal reception unit 21 receives the beacon signal indicating completion of charging of the secondary battery 114 from the measuring instrument 1.

[0227] [Effects of the wireless power transmission system S]

[0228] As described above, in the wireless power transmission system S, the power transmission target identification unit 244 can identify, as a power transmission target, the power reception antenna 110 among the plurality of power reception antennas 110 that can receive the largest amount of electric power transmitted by the power transmission antenna 222. As a result, even in a case where the orientation of the measuring instrument 1 is changed, the power transmission antenna 222 can transmit electric power to the power reception antenna 110 that can most easily receive electric power transmitted from the wireless power transmission apparatus 2. In addition, even when the operator performs work while holding the measuring instrument 1 in his / her hand, wireless power transmission can be efficiently performed.

[0229] The present disclosure is explained based on typical embodiments. The technical scope of the present disclosure is not limited to the scope described in the above embodiments, and various changes and modifications can be made within the scope of the present disclosure. For example, all or a part of the apparatus can be configured with any unit that is functionally or physically dispersed or integrated. Furthermore, new typical embodiments generated by any combination of the typical embodiments are included in the typical embodiments of the present disclosure. Furthermore, the effects of the new typical embodiments resulting from the combination also have the effects of the original typical embodiments.

[0230] For example, although it is exemplified that the measuring instrument 1 includes the power reception module 11 housed in the housing portion ST, the measuring instrument 1 can be configured not to include the power reception module 11, and the main body 12 can have the function of the power reception module 11.

[0231] With respect to the embodiments including the above-described examples, the following appendices are further disclosed.

[0232] (Appendix 1)

[0233] A portable measuring instrument, in which electric power is supplied from a wireless power transfer device for wirelessly supplying electric power to the measuring instrument, the measuring instrument comprising:

[0234] a sensor capable of detecting a person using the measuring instrument;

[0235] a signal transmitting section for transmitting, to the wireless power transfer device, a beacon signal for indicating a state of the measuring instrument detected by the sensor; and

[0236] a power receiving antenna for receiving electric power transmitted from the wireless power transfer device.

[0237] (Appendix 2)

[0238] The measuring instrument according to Appendix 1, wherein,

[0239] the signal transmitting section transmits the beacon signal to the wireless power transfer device in a case where the sensor detects that no person is using the measuring instrument, and does not transmit the beacon signal to the wireless power transfer device in a case where the sensor detects that a person is using the measuring instrument.

[0240] (Appendix 3)

[0241] The measuring instrument according to Appendix 1, wherein,

[0242] the signal transmitting section transmits, to the wireless power transfer device, a beacon signal for indicating presence or absence of a person detected by the sensor as using the measuring instrument.

[0243] (Appendix 4)

[0244] The measuring instrument according to Appendix 2, wherein,

[0245] the sensor is an acceleration sensor, and

[0246] the signal transmitting section transmits the beacon signal to the wireless power transfer device in a case where the acceleration sensor does not detect acceleration, and does not transmit the beacon signal to the wireless power transfer device in a case where the acceleration sensor detects acceleration.

[0247] (Appendix 5)

[0248] The measuring instrument according to Appendix 1, wherein,

[0249] the sensor is a person sensor, and

[0250] the signal transmitting section transmits the beacon signal to the wireless power transmitting apparatus under a condition that the person sensor does not detect a person located within a predetermined distance with respect to the measuring instrument.

[0251] (Appendix 6)

[0252] The measuring instrument according to any one of Appendices 1 to 5, wherein

[0253] The measuring instrument further includes an operation section for receiving a power reception operation for starting power reception, and

[0254] The signal transmitting section transmits a beacon signal indicating that the measuring instrument is in a state capable of receiving power to the wireless power transmitting apparatus in response to the operation section receiving the power reception operation.

[0255] (Appendix 7)

[0256] The measuring instrument according to any one of Appendices 1 to 6, wherein

[0257] The measuring instrument further includes a determination section for determining which of a standardized standard cell and a power reception module having the power reception antenna is accommodated in the measuring instrument,

[0258] The measuring instrument does not transmit the beacon signal to the wireless power transmitting apparatus in a case where the determination section determines that the standard cell is accommodated, and transmits the beacon signal to the wireless power transmitting apparatus in a case where the determination section determines that the power reception module is accommodated.

[0259] (Appendix 8)

[0260] The measuring instrument according to any one of Appendices 1 to 7, wherein

[0261] The measuring instrument further includes:

[0262] a distance identifying section for identifying a distance from the wireless power transmitting apparatus to the measuring instrument, and

[0263] a display section for displaying that the measuring instrument is in a state capable of receiving power in a case where a remaining capacity of a secondary cell of a power reception module having the power reception antenna is less than a threshold value and the distance identified by the distance identifying section is less than or equal to a predetermined distance.

[0264] (Appendix 9)

[0265] A wireless power transmission device for wirelessly transmitting electric power to a portable measuring instrument, the wireless power transmission device comprising:

[0266] a power transmission unit for transmitting electric power from the wireless power transmission device;

[0267] a signal receiving unit for receiving a beacon signal indicating a state of the measuring instrument from the measuring instrument; and

[0268] a power transmission controller for causing the power transmission unit to transmit electric power in a case where it is determined, based on the beacon signal received by the signal receiving unit from the measuring instrument, that the measuring instrument is located within a predetermined distance with respect to the wireless power transmission device and that no person is using the measuring instrument.

[0269] (Appendix 10)

[0270] The wireless power transmission device according to Appendix 9, wherein,

[0271] the power transmission controller does not cause the power transmission unit to transmit electric power even in a case where it is determined that the measuring instrument is located within a predetermined distance with respect to the wireless power transmission device and that no person is using the measuring instrument, within a predetermined time after the beacon signal is received by the signal receiving unit from the measuring instrument.

[0272] (Appendix 11)

[0273] The wireless power transmission device according to Appendix 9, wherein,

[0274] the power transmission controller causes the power transmission unit to start power transmission after a time required for an operator using the measuring instrument to leave the measuring instrument by at least a predetermined distance elapses from when the signal receiving unit receives the beacon signal indicating that the measuring instrument is in a state in which electric power can be received.

[0275] (Appendix 12)

[0276] The wireless power transmission device according to any one of Appendices 9 to 11, wherein,

[0277] the wireless power transmission device further includes a position identifying unit for identifying a position of the measuring instrument based on the beacon signal, and

[0278] the power transmission controller does not cause the power transmission unit to transmit electric power even in a case where it is determined that the measuring instrument is located within a predetermined distance with respect to the wireless power transmission device and that no person is using the measuring instrument, when the measuring instrument is located outside a power-transmittable region in which electric power can be wirelessly transmitted.

[0279] (Appendix 13)

[0280] A wireless power transfer system, comprising:

[0281] a wireless power transfer device for wirelessly transferring power; and

[0282] a portable measuring instrument for receiving power transferred from the wireless power transfer device, wherein the measuring instrument includes:

[0283] a sensor capable of detecting presence of a person using the measuring instrument,

[0284] a signal transmitting section for transmitting a beacon signal indicating a state of the measuring instrument detected by the sensor to the wireless power transfer device, and

[0285] a power receiving antenna for receiving power transmitted from the wireless power transfer device,

[0286] wherein the wireless power transfer device includes:

[0287] a power transmitting section for transmitting power from the wireless power transfer device,

[0288] a signal receiving section for receiving the beacon signal from the measuring instrument, and

[0289] a power transmission controller for causing the power transmitting section to transmit power in a case where it is determined, based on the beacon signal received by the signal receiving section from the measuring instrument, that the measuring instrument is located within a predetermined distance with respect to the wireless power transfer device and that no person is using the measuring instrument.

Claims

1. A portable measuring instrument, wherein power is supplied to the measuring instrument from a wireless power transfer device for wirelessly supplying power, the measuring instrument comprising: a sensor capable of detecting a person using the measuring instrument; a signal transmitting section for transmitting a beacon signal indicating a state of the measuring instrument detected by the sensor to the wireless power transfer device; and a power receiving antenna for receiving power transmitted from the wireless power transfer device.

2. The measuring instrument according to claim 1, wherein the signal transmitting section transmits the beacon signal to the wireless power transfer device in a case where the sensor detects that no person is using the measuring instrument, and does not transmit the beacon signal to the wireless power transfer device in a case where the sensor detects that a person is using the measuring instrument.

3. The measuring instrument according to claim 1, wherein the signal transmitting section transmits a beacon signal indicating presence or absence of a person detected by the sensor as being in use of the measuring instrument to the wireless power transfer device.

4. The measuring instrument according to claim 2, wherein the sensor is an acceleration sensor, and the signal transmitting section transmits the beacon signal to the wireless power transfer device in a case where the acceleration sensor does not detect acceleration, and does not transmit the beacon signal to the wireless power transfer device in a case where the acceleration sensor detects acceleration.

5. The measuring instrument according to claim 1, wherein the sensor is a person sensor, and the signal transmitting section transmits the beacon signal to the wireless power transfer device in a condition where the person sensor does not detect a person within a predetermined distance with respect to the measuring instrument.

6. The measuring instrument according to claim 1, wherein the measuring instrument further comprises an operation section for receiving a power receiving operation for starting power reception, and the signal transmitting section transmits a beacon signal indicating that the measuring instrument is in a state capable of receiving power to the wireless power transfer device in response to the operation section receiving the power receiving operation.

7. The measuring instrument according to claim 1, wherein the measuring instrument further comprises a judging section for judging which of a standardized battery and a power receiving module having the power receiving antenna is housed in the measuring instrument, the measuring instrument does not transmit the beacon signal to the wireless power transfer device in a case where the judging section judges that the standardized battery is housed in the measuring instrument (1), and transmits the beacon signal to the wireless power transfer device in a case where the judging section judges that the power receiving module is housed.

8. The measuring instrument according to any one of claims 1 to 7, wherein the measuring instrument further comprises: a distance identifying section for identifying a distance from the wireless power transfer device to the measuring instrument, and the signal transmitting section transmits the beacon signal to the wireless power transfer device in a case where the distance identifying section identifies that the distance is equal to or less than a predetermined distance. The display unit displays that the measuring instrument is in a state capable of receiving power when the remaining capacity of the secondary battery of the power-receiving module having the power-receiving antenna is less than a threshold value and the distance identified by the distance identification unit is less than or equal to a predetermined distance.

9. A wireless power transmission device for wirelessly transmitting power to a portable measuring instrument, the wireless power transmission device comprising: a power transmission unit configured to transmit power from the wireless power transmission device; a signal reception unit configured to receive a beacon signal from the measuring instrument, the beacon signal indicating a state of the measuring instrument; and a power transmission controller configured to cause the power transmission unit to transmit power when it is determined, based on the beacon signal received by the signal reception unit from the measuring instrument, that the measuring instrument is located within a predetermined distance from the wireless power transmission device and that no person is using the measuring instrument.

10. The wireless power transmission device according to claim 9, wherein the power transmission controller does not cause the power transmission unit to transmit power even when it is determined that the measuring instrument is located within the predetermined distance from the wireless power transmission device and that no person is using the measuring instrument, within a predetermined time after the beacon signal is received by the signal reception unit from the measuring instrument.

11. The wireless power transmission device according to claim 9, wherein the power transmission controller causes the power transmission unit to start power transmission after a time required for an operator using the measuring instrument to move away from the measuring instrument by at least a predetermined distance elapses since the signal reception unit receives the beacon signal indicating that the measuring instrument is in a state capable of receiving power.

12. The wireless power transmission device according to any one of claims 9 to 11, wherein the wireless power transmission device further includes a position identification unit configured to identify a position of the measuring instrument based on the beacon signal, and the power transmission controller does not cause the power transmission unit to transmit power even when it is determined that the measuring instrument is located within the predetermined distance from the wireless power transmission device and that no person is using the measuring instrument, when the measuring instrument is located outside a power-transmissible region in which power can be wirelessly transmitted.

13. A wireless power transmission system comprising: a wireless power transmission device for wirelessly transmitting power; and a portable measuring instrument for receiving power transmitted from the wireless power transmission device, wherein the measuring instrument includes: a sensor capable of detecting presence of a person using the measuring instrument, a signal transmission unit configured to transmit a beacon signal to the wireless power transmission device, the beacon signal indicating a state of the measuring instrument detected by the sensor, and a power-receiving antenna configured to receive power transmitted from the wireless power transmission device, wherein the wireless power transmission device includes: a power transmission unit configured to transmit power from the wireless power transmission device, a signal reception unit configured to receive the beacon signal from the measuring instrument, and a power transmission controller configured to cause the power transmission unit to transmit power when it is determined, based on the beacon signal received by the signal reception unit from the measuring instrument, that the measuring instrument is located within a predetermined distance from the wireless power transmission device and that no person is using the measuring instrument. ​ A power transmission controller configured to cause the power transmission unit to transmit power when it is determined, based on a beacon signal received by the signal receiving unit from the measuring instrument, that the measuring instrument is located within a predetermined distance from the wireless power transmission apparatus and that no person is using the measuring instrument.

Images