Wireless power supply communication system

Abstract

The operation modes of a lower-level unit (10b) include a normal mode (M2) and a standby mode (M1) in which power consumption is lower than in the normal mode (M2). In a situation in which the operation mode of the lower-level unit (10b) is the normal mode (M2), a lower-level control device (34) switches the operation mode of the lower-level unit (10b) to the standby mode (M1) when a wireless power supply communication stop time (Ts) during which a lower-level communication device (33) is not wirelessly communicating with an upper-level communication device (24) and a power reception device (31) is not receiving power from a power transmission device (26) is equal to or longer than a predetermined time (Tsth).

Description

Wireless power supply communication system

[0001] The present disclosure relates to a wireless power supply communication system.

[0002] Patent Document 1 discloses a wireless power supply system that wirelessly supplies power from a power source to a device. The wireless power supply system includes a transmitter and a receiver. The transmitter converts the power supplied from the power source into microwaves. The transmitter transmits the converted microwaves to the receiver. The receiver converts the microwaves received from the transmitter into power. The converted power is supplied to the device and also charges the battery.

[0003] Japanese Patent Application Laid-Open No. 2014-223018

[0004] When the power supply from the power source to the transmitter stops, the transmission of microwaves from the transmitter to the receiver stops, so the power supply from the power source to the device stops and the charging of the battery stops. In this case, the power charged in the battery is supplied to the device, but if the stop time of the power supply from the power source becomes long, there is a risk of battery depletion.

[0005] A wireless power supply communication system according to one aspect of the present disclosure comprises a higher-level unit and a lower-level unit configured to wirelessly communicate with the higher-level unit and to receive wireless power from the higher-level unit. The higher-level unit includes a higher-level communication device, a power transmission device, a main power supply configured to supply power to the higher-level communication device and the power transmission device, and a circuit breaker configured to interrupt the power supply from the main power supply to the higher-level communication device and the power transmission device. The lower-level unit includes a lower-level communication device configured to wirelessly communicate with the higher-level communication device, a power receiving device configured to receive power from the power transmission device, a battery configured to charge the power received by the power receiving device, and a lower-level control device configured to recognize the communication status of the lower-level communication device and the power receiving status of the power receiving device. The operating modes of the lower-level unit include a normal mode and a standby mode which consumes less power than the normal mode. When the operating mode is the normal mode, if the wireless power supply communication downtime, during which the lower-level communication device is not communicating wirelessly with the upper-level communication device and the power receiving device is not receiving power from the power transmitting device, exceeds a predetermined time, the lower-level control device is configured to switch the operating mode to the standby mode.

[0006] Figure 1 is a block diagram showing the configuration of a wireless power supply and communication system. Figure 2 is a diagram showing the wireless power supply and communication system of Figure 1 with the circuit breaker in the off state. Figure 3 is a correlation diagram of the operating modes of the lower-level units in Figure 1. Figure 4 is a correlation diagram of the operating modes of the lower-level units in a modified example.

[0007] An embodiment of the wireless power supply communication system 10 will be described below with reference to Figures 1 to 3. The wireless power supply communication system 10 of this embodiment is used in a factory. As shown in Figure 1, the wireless power supply communication system 10 comprises an upper unit 10a and a lower unit 10b. The lower unit 10b is configured to communicate wirelessly with the upper unit 10a, as indicated by arrow A1. The wireless communication standard of this embodiment is IO-Link® Wireless. The lower unit 10b is configured to receive wireless power from the upper unit 10a, as indicated by arrow A2. The wireless power supply method of this embodiment is the microwave method. In Figure 1, power lines are shown as solid lines and signal lines are shown as dashed lines.

[0008] <Higher-level unit> The higher-level unit 10a includes a main power supply 21, a circuit breaker 22, a DC power supply 23, a higher-level control device 24, a higher-level communication device 25, and a power transmission device 26.

[0009] In this embodiment, the main power supply 21 is an AC power supply. The DC power supply 23 is connected to the main power supply 21. The DC power supply 23 converts the AC power supplied from the main power supply 21 into DC power. The higher-level control device 24 and the higher-level communication device 25 are each connected to the DC power supply 23. The higher-level control device 24 and the higher-level communication device 25 operate using the DC power supplied from the DC power supply 23. Therefore, the main power supply 21 is configured to supply power to the higher-level control device 24 and the higher-level communication device 25 via the DC power supply 23.

[0010] The higher-level control unit (higher-level control circuit) 24 may include one or more processors or arithmetic units that execute various processes according to a control program. The higher-level control unit 24 may also include one or more dedicated hardware circuits, such as application-specific integrated circuits (ASICs), that execute at least some of the various processes. In this embodiment, the higher-level control unit 24 is a PLC (Programmable Logic Controller). The higher-level communication device (higher-level communication circuit) 25 is connected to the higher-level control unit 24. The higher-level communication device 25 is configured to enable wireless communication. In this embodiment, the higher-level communication device 25 is an IO-Link Wireless master. The higher-level control unit 24 is configured to switch the operating mode (described later) of the lower-level unit 10b. The higher-level control unit 24 transmits parameters for switching the operating mode of the lower-level unit 10b to the higher-level communication device 25. The higher-level communication device 25 receives parameters for switching the operating mode of the lower-level unit 10b from the higher-level control unit 24. The higher-level communication device 25 transmits parameters for switching the operating mode of the lower-level unit 10b to the lower-level unit 10b.

[0011] The power transmission device (power transmission circuit) 26 is connected to the main power supply 21. The main power supply 21 is configured to supply power to the power transmission device 26. The power transmission device 26 converts the power supplied from the main power supply 21 into microwaves. The power transmission device 26 sends the converted microwaves to the lower unit 10b.

[0012] The circuit breaker 22 is installed between the main power supply 21 and the DC power supply 23, and between the main power supply 21 and the power transmission device 26. The circuit breaker 22 is configured to interrupt the power supply from the main power supply 21 to the higher-level control device 24, the higher-level communication device 25, and the power transmission device 26.

[0013] <Lower Unit> The lower unit 10b in this embodiment is a digital input unit. The lower unit 10b is connected to the detection unit 11. The detection unit 11 is, for example, a switch. The detection unit 11 is attached to, for example, an air cylinder (not shown). The detection unit 11 detects the position of the air cylinder. The lower unit 10b acquires the detection result from the detection unit 11. The lower unit 10b transmits the acquired detection result from the detection unit 11 to the upper unit 10a.

[0014] The lower unit 10b includes a power receiving device 31, a battery 32, a lower communication device 33, a lower control device 34, an internal circuit (not shown), a power switch 35, and a temperature sensor 36.

[0015] The power receiving device (power receiving circuit) 31 is configured to receive power from the power transmitting device 26. In this embodiment, the power receiving device 31 converts microwaves received from the power transmitting device 26 into electricity. As a result, the lower unit 10b is wirelessly powered from the upper unit 10a. The battery 32 is configured to be charged with the power received by the power receiving device 31. In this embodiment, all the power received by the power receiving device 31 is used to charge the battery 32.

[0016] The lower communication device 33, the lower control device 34, and the internal circuit are each connected to the power receiving device 31. Power charged in the battery 32 is supplied to the lower communication device 33, the lower control device 34, and the internal circuit via the power receiving device 31. The lower communication device 33, the lower control device 34, and the internal circuit operate using the power supplied from the battery 32 via the power receiving device 31.

[0017] The power switch 35 is a switch for switching the power to the lower unit 10b. The power switch 35 is operated by the user. The power switch 35 is located between the battery 32 and the power receiving device 31. When the power switch 35 is ON, the lower unit 10b is in a power-on state, with power supplied from the battery 32 to the lower communication device 33, the lower control device 34, and the internal circuitry. When the power switch 35 is OFF, the lower unit 10b is in a power-off state, with no power supplied from the battery 32 to the lower communication device 33, the lower control device 34, and the internal circuitry.

[0018] The lower communication device (lower communication circuit) 33 is configured to communicate wirelessly with the upper communication device 25 of the upper unit 10a. Specifically, the lower communication device 33 transmits the detection result of the detection unit 11 to the upper communication device 25. The upper communication device 25 receives the detection result of the detection unit 11 from the lower communication device 33. The upper communication device 25 outputs the received detection result of the detection unit 11 to the upper control device 24. The upper communication device 25 also transmits parameters for switching the operating mode of the lower unit 10b to the lower communication device 33. The lower communication device 33 receives parameters for switching the operating mode of the lower unit 10b from the upper communication device 25.

[0019] The lower-level control unit (lower-level control circuit) 34 may include one or more processors or arithmetic units that execute various processes according to a control program. The lower-level control unit 34 may also include one or more dedicated hardware circuits, such as application-specific integrated circuits (ASICs), that execute at least some of the various processes. In this embodiment, the lower-level control unit 34 is an MCU (Micro Controller Unit). The lower-level control unit 34 is connected to the power receiving device 31. The lower-level control unit 34 is configured to recognize the power receiving status of the power receiving device 31, that is, whether or not the power receiving device 31 is receiving power. The lower-level control unit 34 is connected to the lower-level communication device 33. The lower-level control unit 34 is configured to recognize the communication status of the lower-level communication device 33, that is, whether or not the lower-level communication device 33 is communicating wirelessly with the upper-level communication device 25.

[0020] The power receiving device 31 is configured to manage the temperature Tb and charge level Xb of the battery 32. Specifically, the power receiving device 31 is connected to a temperature sensor 36. The temperature sensor 36 detects the temperature Tb of the battery 32. The power receiving device 31 obtains the temperature Tb of the battery 32 from the temperature sensor 36.

[0021] As described above, the lower-level control unit 34 is connected to the power receiving device 31. Therefore, the lower-level control unit 34 can recognize the temperature Tb and the charge level Xb of the battery 32 via the power receiving device 31.

[0022] When the circuit breaker 22 of the upper unit 10a is ON, power is supplied from the main power supply 21 to the upper communication device 25, so the upper communication device 25 is operational. Therefore, when the circuit breaker 22 is ON, wireless communication is possible between the upper communication device 25 of the upper unit 10a and the lower communication device 33 of the lower unit 10b. Also, when the circuit breaker 22 is ON, power is supplied from the main power supply 21 to the power transmission device 26, so the power transmission device 26 can send microwaves to the power receiving device 31. Therefore, when the circuit breaker 22 is ON, wireless power is supplied from the upper unit 10a to the lower unit 10b.

[0023] Factories sometimes have extended shutdown periods lasting several weeks to several months, coinciding with long holidays or other occasions. During these extended shutdown periods, the circuit breaker 22 of the upper unit 10a is turned off.

[0024] As shown in Figure 2, when the breaker 22 of the upper unit 10a is in the off state, power is not supplied from the main power supply 21 to the upper communication device 25, and therefore the upper communication device 25 does not operate. Therefore, when the breaker 22 is in the off state, the upper communication device 25 of the upper unit 10a and the lower communication device 33 of the lower unit 10b do not communicate wirelessly. Also, when the breaker 22 is in the off state, power is not supplied from the main power supply 21 to the power transmission device 26, and therefore the power transmission device 26 cannot send microwaves to the power receiving device 31. Therefore, when the breaker 22 is in the off state, wireless power is not supplied from the upper unit 10a to the lower unit 10b.

[0025] <Operating Modes of the Lower Unit> As shown in Figure 3, the operating modes of the lower unit 10b include a normal mode M2 ​​and a standby mode M1. Normal mode M2 ​​and standby mode M1 are operating modes when the lower unit 10b is powered on. The power consumption of the lower unit 10b in standby mode M1 is less than the power consumption of the lower unit 10b in normal mode M2. For example, the power consumption of the lower unit 10b in standby mode M1 is 30 mW.

[0026] The normal mode M2 ​​includes two modes: a first normal mode M2a and a second normal mode M2b. In the first normal mode M2a, the power consumption of the lower unit 10b is, for example, 300 mW. In the second normal mode M2b, the power consumption of the lower unit 10b is less than that of the lower unit 10b in the first normal mode M2a. Therefore, the second normal mode M2b can be said to be a power-saving mode compared to the first normal mode M2a. In the second normal mode M2b, the power consumption of the lower unit 10b is, for example, 200 mW.

[0027] The lower control unit 34 is configured to switch the operating mode of the lower unit 10b. The conditions for switching the operating mode of the lower unit 10b are described in detail below. When the power switch 35 is switched on while the power switch 35 is in the off state, that is, when the lower unit 10b is powered off, the lower control unit 34 sets the operating mode of the lower unit 10b to standby mode M1.

[0028] When the operating mode of the lower unit 10b is in standby mode M1, and the power receiving device 31 is receiving power, i.e., the lower unit 10b is receiving wireless power, and the charge level Xb of the battery 32 is equal to or greater than the first charge level Xb1, and the temperature Tb of the battery 32 is less than the first temperature Tb1, the lower control device 34 switches the operating mode to the first normal mode M2a. The first charge level Xb1 is, for example, 20%. The first temperature Tb1 is, for example, 50°C.

[0029] When the operating mode of the lower unit 10b is the first normal mode M2a, if the charge level Xb of the battery 32 falls below the second charge level Xb2, which is the first switching charge level, the lower control device 34 switches the operating mode to the second normal mode M2b. The second charge level Xb2 is greater than the first charge level Xb1. The second charge level Xb2 is, for example, 50%.

[0030] Furthermore, in this embodiment, when the lower communication device 33 receives a parameter from the upper communication device 25 to switch the operating mode of the lower unit 10b to the second normal mode M2b while the operating mode of the lower unit 10b is in the first normal mode M2a, the lower control device 34 switches the operating mode to the second normal mode M2b.

[0031] In other words, when the operating mode of the lower unit 10b is the first normal mode M2a, if the charge level Xb of the battery 32 falls below the second charge level Xb2, or if the lower control device 34 receives a parameter from the upper unit 10a to switch the operating mode to the second normal mode M2b, the lower control device 34 switches the operating mode to the second normal mode M2b.

[0032] When the operating mode of the lower unit 10b is the second normal mode M2b, and the lower communication device 33 receives a parameter from the upper communication device 25 to switch the operating mode to the first normal mode M2a, and the charge level Xb of the battery 32 is the second charge level Xb2 or higher, the lower control device 34 switches the operating mode to the first normal mode M2a.

[0033] When the lower unit 10b is operating in standby mode M1, first normal mode M2a, or second normal mode M2b, and the power switch 35 is switched from on to off, the lower unit 10b will be powered off. In other words, regardless of the operating mode of the lower unit 10b, the lower unit 10b is configured to be powered off when the power switch 35 is switched from on to off.

[0034] When the operating mode of the lower unit 10b is the first normal mode M2a or the second normal mode M2b, if the charge level Xb of the battery 32 falls below the first charge level Xb1, if the temperature Tb of the battery 32 rises to or above the second temperature Tb2, or if the wireless power supply communication stop time Ts (described later) rises to or above a predetermined time Tsth, the lower control device 34 switches the operating mode to standby mode M1. The second temperature Tb2 is equal to or above the first temperature Tb1. The second temperature Tb2 is, for example, 55°C.

[0035] The wireless power supply communication downtime Ts is the time when the lower communication device 33 is not communicating wirelessly with the upper communication device 25, and the power receiving device 31 is not receiving power from the power transmitting device 26. In other words, the wireless power supply communication downtime Ts is the time when the upper unit 10a and the lower unit 10b are not communicating wirelessly, and the upper unit 10a is not wirelessly supplying power to the lower unit 10b.

[0036] The predetermined time Tsth is set to a time that allows for determination of whether the state in which the upper unit 10a and the lower unit 10b are not communicating wirelessly and the upper unit 10a is not wirelessly supplying power to the lower unit 10b is due to the circuit breaker 22 being turned off. For example, even when the circuit breaker 22 is on, it is expected that there will be a period of several tens of seconds to several minutes during which the upper unit 10a is not wirelessly supplying power to the lower unit 10b. For this reason, the predetermined time Tsth is set to a time longer than the expected period during which the upper unit 10a is not wirelessly supplying power to the lower unit 10b when the circuit breaker 22 is on. In this embodiment, the predetermined time Tsth is set to 600 seconds.

[0037] Thus, the lower unit 10b operates in normal mode M2 ​​while wireless communication and wireless power supply are in progress. When the wireless power supply communication downtime Ts exceeds a predetermined time Tsth, the operating mode of the lower unit 10b switches from normal mode M2 ​​to standby mode M1, allowing the lower unit 10b to operate with less power consumption than in normal mode M2.

[0038] [Operation of this Embodiment] The operation of this embodiment will now be explained. As described above, during long-term factory shutdowns, the circuit breaker 22 of the upper unit 10a is turned off. At this time, it is preferable that the power switch 35 of the lower unit 10b is also turned off, so that the lower unit 10b is also powered off. However, if the user forgets to turn off the power switch 35, or if the power switch 35 is in a position that is difficult to operate due to the placement of the lower unit 10b in the factory, the power switch 35 may not be turned off, and the lower unit 10b may remain powered on.

[0039] In this case, wireless power is no longer supplied from the upper unit 10a to the lower unit 10b, and therefore the battery 32 stops charging. Also, the lower communication device 33, the lower control device 34, and the internal circuitry are supplied with the power that was charged in the battery 32 during wireless power supply. For this reason, if the lower unit 10b continues to operate in normal mode M2 ​​even after the breaker 22 of the upper unit 10a is turned off, there is a risk that the battery 32 will run out. If the battery 32 runs out, the lower unit 10b cannot be put into operation immediately after a long period of factory shutdown.

[0040] In this embodiment, the operating modes of the lower unit 10b include a normal mode M2 ​​and a standby mode M1 which consumes less power than the normal mode M2. When the operating mode of the lower unit 10b is in normal mode M2, if the wireless power supply communication stop time Ts exceeds a predetermined time Tsth, the lower control device 34 of the lower unit 10b switches the operating mode to standby mode M1. Therefore, when the breaker 22 is turned off, the upper unit 10a and the lower unit 10b do not communicate wirelessly, and wireless power is no longer supplied from the upper unit 10a to the lower unit 10b, the operating mode of the lower unit 10b is automatically switched from normal mode M2 ​​to standby mode M1. Consequently, the decrease in the charge rate Xb of the battery 32 is suppressed, making it less likely for the battery 32 to run out. As a result, the lower unit 10b can be put into operation immediately after a long period of factory downtime.

[0041] [Effects of the Present Embodiment] The effects of the present embodiment will be described. (1) The wireless power supply communication system 10 includes an upper unit 10a and a lower unit 10b. The lower unit 10b wirelessly communicates with the upper unit 10a and is wirelessly powered by the upper unit 10a.

[0042] The upper unit 10a has an upper communication device 25, a power transmission device 26, a main power supply 21, and a breaker 22. The main power supply 21 supplies power to the upper communication device 25 and the power transmission device 26. The breaker 22 can cut off the power supply from the main power supply 21 to the upper communication device 25 and the power transmission device 26.

[0043] The lower unit 10b has a lower communication device 33, a power receiving device 31, a battery 32, and a lower control device 34. The lower communication device 33 is configured to be able to wirelessly communicate with the upper communication device 25. The power receiving device 31 is configured to be able to receive power from the power transmission device 26. The battery 32 is charged with the power received by the power receiving device 31. The lower control device 34 is configured to be able to recognize the communication status of the lower communication device 33 and the power receiving status of the power receiving device 31.

[0044] The operation modes of the lower unit 10b include a normal mode M2 and a standby mode M1 with lower power consumption than the normal mode M2. When the operation mode of the lower unit 10b is the normal mode M2, and the wireless power supply communication stop time Ts during which the lower communication device 33 is not wirelessly communicating with the upper communication device 25 and the power receiving device 31 is not receiving power from the power transmission device 26 becomes equal to or longer than a predetermined time Tsth, the lower control device 34 switches the operation mode to the standby mode M1.

[0045] According to this configuration, when the breaker 22 of the upper unit 10a is turned off, the operation mode of the lower unit 10b is automatically switched from the normal mode M2 to the standby mode M1 with lower power consumption than the normal mode M2. As a result, the decrease in the charging rate Xb of the battery 32 during the long-term shutdown period of the factory is suppressed, so that the battery 32 is less likely to run out. As a result, the lower unit 10b can be immediately put into operation after the long-term shutdown period of the factory.

[0046] (2) When the power receiving device 31 receives power from the power transmitting device 26 in a situation where the operation mode of the lower unit 10b is the standby mode M1, the lower control device 34 switches the operation mode to the normal mode M2.

[0047] According to this configuration, when the breaker 22 of the upper unit 10a is turned on after a long-term factory shutdown period and wireless power supply from the upper unit 10a to the lower unit 10b is restored, the operation mode of the lower unit 10b is automatically switched from the standby mode M1 to the normal mode M2. Therefore, after a long-term factory shutdown period, the lower unit 10b can operate in the normal mode M2.

[0048] (3) The normal mode M2 includes a first normal mode M2a and a second normal mode M2b with lower power consumption than the first normal mode M2a. When the charging rate Xb of the battery 32 becomes less than the second charging rate Xb2 in a situation where the operation mode of the lower unit 10b is the first normal mode M2a, the lower control device 34 switches the operation mode to the second normal mode M2b.

[0049] According to this configuration, when the charging rate Xb of the battery 32 decreases, the operation mode of the lower unit 10b is automatically switched from the first normal mode M2a to the second normal mode M2b with lower power consumption than the first normal mode M2a. Therefore, in a situation where the charging rate Xb of the battery 32 decreases, the decrease amount of the charging rate Xb of the battery 32 can be suppressed.

[0050] (4) The lower unit 10b has a power switch 35 operated by the user. When the power switch 35 is turned off, the lower unit 10b enters a power-off state where power is not supplied from the battery 32 to the lower communication device 33 and the lower control device 34.

[0051] With this configuration, if the power switch 35 is turned off by the user, the lower unit 10b will be powered off regardless of its operating mode. (5) As described above, even when the breaker 22 is on, it is expected that there will be a period of time when the upper unit 10a does not wirelessly supply power to the lower unit 10b. For this reason, if the lower communication device 33 does not wirelessly communicate with the upper communication device 25, and the power receiving device 31 stops receiving power from the power transmitting device 26, the operating mode of the lower unit 10b may switch to standby mode M1 immediately, even though the breaker 22 is not turned off.

[0052] In this embodiment, when the wireless power supply communication downtime Ts exceeds a predetermined time Tsth, the lower-level control device 34 switches the operating mode of the lower-level unit 10b from normal mode M2 ​​to standby mode M1. Therefore, it is possible to avoid the lower-level unit 10b switching from normal mode M2 ​​to standby mode M1 even though the breaker 22 is not turned off. Thus, unnecessary switching of the operating mode of the lower-level unit 10b can be suppressed.

[0053] (6) When the operating mode of the lower unit 10b is in standby mode M1, and the lower unit 10b is receiving wireless power, and the charge level Xb of the battery 32 is at or above the first charge level Xb1, and the temperature Tb of the battery 32 is below the first temperature Tb1, the lower control device 34 switches the operating mode to the first normal mode M2a.

[0054] This configuration prevents the lower unit 10b from switching to the first normal mode M2a when one or more of the following conditions are met: the lower unit 10b is not receiving wireless power, the charge level Xb of the battery 32 is low, or the temperature Tb of the battery 32 is high.

[0055] (7) The upper unit 10a is configured to transmit parameters to the lower unit 10b for switching the operating mode of the lower unit 10b. When the lower communication device 33 receives parameters from the upper communication device 25 for switching the operating mode of the lower unit 10b to the second normal mode M2b while the operating mode of the lower unit 10b is in the first normal mode M2a, the lower control device 34 switches the operating mode of the lower unit 10b to the second normal mode M2b.

[0056] With this configuration, the lower-level control unit 34 can switch the operating mode of the lower-level unit 10b from the first normal mode M2a to the second normal mode M2b based on a command from the upper-level unit 10a. For example, if a decrease in the amount of power supplied to the lower-level unit 10b is expected, the operating mode of the lower-level unit 10b can be switched from the first normal mode M2a to the second normal mode M2b even if the charge level Xb of the battery 32 is 2 or higher.

[0057] Furthermore, when the operating mode of the lower unit 10b is the second normal mode M2b, if the lower communication device 33 receives a parameter from the upper communication device 25 to switch the operating mode of the lower unit 10b to the first normal mode M2a, and the charge level Xb of the battery 32 is the second charge level Xb2 or higher, the lower control device 34 switches the operating mode of the lower unit 10b to the first normal mode M2a.

[0058] With this configuration, if the charge level Xb of the battery 32 is equal to or greater than the second charge level Xb2, the lower control unit 34 can switch the operating mode of the lower unit 10b from the second normal mode M2b to the first normal mode M2a based on a command from the upper unit 10a. For example, if an increase in the amount of power supplied to the lower unit 10b is expected, the operating mode of the lower unit 10b can be switched from the second normal mode M2b to the first normal mode M2a.

[0059] (8) When the operating mode of the lower unit 10b is in normal mode M2, if the charge level Xb of the battery 32 falls below the first charge level Xb1, the lower control device 34 switches the operating mode to standby mode M1. As a result, even if the charge level Xb of the battery 32 decreases, the operating mode of the lower unit 10b automatically switches to standby mode M1. Therefore, the occurrence of battery depletion can be suppressed.

[0060] (9) When the operating mode of the lower unit 10b is in normal mode M2, if the temperature Tb of the battery 32 rises to or above the second temperature Tb2, the lower control device 34 switches the operating mode to standby mode M1. As a result, even if the temperature Tb of the battery 32 rises, the operating mode of the lower unit 10b automatically switches to standby mode M1. Therefore, the rise in the temperature Tb of the battery 32 can be suppressed.

[0061] [Example of Modification] The above embodiment can be implemented with the following modifications. The above embodiment and the following examples of modifications can be combined with each other to the extent that they do not contradict each other technically.

[0062] The number of lower units 10b in the wireless power supply communication system 10 is not limited to one. The wireless power supply communication system 10 may have two or more lower units 10b. In this case, the upper unit 10a may communicate wirelessly with each of the two or more lower units 10b and also wirelessly supply power to each of the two or more lower units 10b.

[0063] The wireless communication standard between the upper-level communication device 25 and the lower-level communication device 33 is not limited to IO-Link Wireless and may be changed as appropriate. The wireless communication standard may be, for example, Wi-Fi (registered trademark) or Bluetooth (registered trademark).

[0064] - The host communication device 25 is not limited to an IO-Link Wireless master. Any wireless communication device conforming to the wireless communication standard can be used as the host communication device 25. - The wireless power supply method from the power transmission device 26 to the power receiving device 31 is not limited to a microwave method and may be changed as appropriate. The wireless power supply method may be, for example, a high-frequency electromagnetic coupling method, a magnetic field resonance method, or an electric field coupling method.

[0065] - The lower unit 10b is not limited to a digital input unit. The lower unit 10b may be, for example, a digital output unit, an analog input unit, an analog output unit, a digital input / output unit, or an analog input / output unit.

[0066] The lower unit 10b may be a sensor such as a flow sensor or a pressure sensor. If the lower unit 10b is a digital input unit, the connection destination of the lower unit 10b was the detection unit 11, but the connection destination of the lower unit 10b may be changed as appropriate depending on the type of lower unit 10b.

[0067] - The detection unit 11 is not limited to a switch. The detection unit 11 may be a sensor, for example. - The mounting destination of the detection unit 11 is not limited to an air cylinder. The mounting destination of the detection unit 11 may be an air pipe, for example.

[0068] - Of the power received by the power receiving device 31, a portion may be supplied to the lower communication device 33, the lower control device 34, and the internal circuit, while the remaining power may be used to charge the battery 32. - In the above embodiment, the power charged in the battery 32 was supplied to the lower communication device 33, the lower control device 34, and the internal circuit via the power receiving device 31, but it may also be supplied directly to the lower communication device 33, the lower control device 34, and the internal circuit without going through the power receiving device 31. In this case, the power switch 35 is provided in the power supply path extending from the battery 32 to the lower communication device 33, the lower control device 34, and the internal circuit.

[0069] - In the above embodiment, the power receiving device 31 managed the temperature Tb of the battery 32, but the lower-level control device 34 may also manage the temperature Tb of the battery 32. - In the above embodiment, the power receiving device 31 managed the charge level Xb of the battery 32, but the lower-level control device 34 may also manage the charge level Xb of the battery 32.

[0070] - When the lower unit 10b is in standby mode M1, if the lower unit 10b is receiving wireless power, the lower control device 34 may switch the operating mode of the lower unit 10b to normal mode M2, regardless of the charge level Xb and temperature Tb of the battery 32. Even in this case, the effect (2) of the above embodiment can be obtained.

[0071] - The number of normal modes M2 is not limited to two. There may be one or three or more normal modes M2. - The upper unit 10a does not need to be configured to transmit parameters to the lower unit 10b for switching the operating mode of the lower unit 10b. In this case, the lower control device 34 may switch the operating mode of the lower unit 10b from the second normal mode M2b to the first normal mode M2a based solely on the charge rate Xb of the battery 32. Specifically, when the operating mode of the lower unit 10b is the second normal mode M2b, if the charge rate Xb of the battery 32 becomes the second charge rate Xb2 or higher, the lower control device 34 switches the operating mode to the first normal mode M2a.

[0072] - The lower-level control unit 34 may switch the operating mode of the lower-level unit 10b from normal mode M2 ​​to standby mode M1 based solely on the wireless power supply communication downtime Ts. That is, when the operating mode of the lower-level unit 10b is in normal mode M2, if the charge level Xb of the battery 32 falls below the first charge level Xb1 or the temperature Tb of the battery 32 rises to or exceeds the second temperature Tb2, the lower-level control unit 34 does not need to switch the operating mode to standby mode M1.

[0073] As shown in Figure 4, when the operating mode of the lower unit 10b is in normal mode M2, the lower control device 34 may switch the operating mode to standby mode M1 if at least one of the first and second conditions is met. The first condition is that the wireless power supply communication stop time Ts is equal to or greater than a predetermined time Tsth and the charge rate Xb of the battery 32 is less than the first charge rate Xb1 as the second switching charge rate. The second condition is that the wireless power supply communication stop time Ts is equal to or greater than a predetermined time Tsth and the temperature Tb of the battery 32 is equal to or greater than the second temperature Tb2 as a predetermined temperature.

[0074] With this configuration, when the circuit breaker 22 of the upper unit 10a is turned off and the charge level Xb of the battery 32 decreases, the operating mode of the lower unit 10b automatically switches to standby mode M1. Therefore, it is possible to suppress the occurrence of battery depletion, especially in situations where battery depletion is likely to occur.

[0075] Furthermore, when the circuit breaker 22 of the upper unit 10a is turned off and the temperature Tb of the battery 32 rises, the operating mode of the lower unit 10b automatically switches to standby mode M1. Therefore, it is possible to suppress the occurrence of battery depletion and the rise in the temperature Tb of the battery 32.

[0076] The specific values ​​of the first charge level Xb1, the second charge level Xb2, the first temperature Tb1, the second temperature Tb2, and the predetermined time Tst may be changed as appropriate.

Claims

1. The system comprises a higher-level unit and a lower-level unit configured to wirelessly communicate with the higher-level unit and to receive wireless power from the higher-level unit, wherein the higher-level unit includes a higher-level communication device, a power transmission device, a main power supply configured to supply power to the higher-level communication device and the power transmission device, and a circuit breaker configured to interrupt the power supply from the main power supply to the higher-level communication device and the power transmission device, wherein the lower-level unit includes a lower-level communication device configured to wirelessly communicate with the higher-level communication device, a power receiving device configured to receive power from the power transmission device, a battery configured to charge the power received by the power receiving device, and a lower-level control device configured to recognize the communication status of the lower-level communication device and the power receiving status of the power receiving device, and the operating modes of the lower-level unit include a normal mode and a standby mode which consumes less power than the normal mode. A wireless power supply communication system in which, when the operating mode is the normal mode, the lower-level communication device is not communicating wirelessly with the upper-level communication device and the power receiving device is not receiving power from the power transmitting device, and the wireless power supply communication downtime exceeds a predetermined time, the lower-level control device is configured to switch the operating mode to the standby mode.

2. The wireless power supply communication system according to claim 1, wherein, when the power receiving device receives power from the power transmitting device while the operating mode is the standby mode, the lower-level control device is configured to switch the operating mode to the normal mode.

3. The wireless power supply communication system according to claim 1 or 2, wherein the normal mode includes a first normal mode and a second normal mode which consumes less power than the first normal mode, and when the operating mode is the first normal mode, the lower control unit is configured to switch the operating mode to the second normal mode if the battery charge level falls below a first switching charge level.

4. The wireless power supply communication system according to any one of claims 1 to 3, wherein the lower unit has a power switch operated by a user, and when the power switch is turned off, the lower unit is configured to be in a power-off state in which power is not supplied from the battery to the lower communication device and the lower control device.

5. The wireless power supply communication system according to any one of claims 1 to 4, wherein, in a situation where the operating mode is the normal mode, if the wireless power supply communication stop time is equal to or greater than the predetermined time and the battery charge level falls below the second switching charge level, and if the wireless power supply communication stop time is equal to or greater than the predetermined time and the battery temperature rises above the predetermined temperature, the lower-level control device is configured to switch the operating mode to the standby mode.

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