JP7014659B2 - A device for controlling the power supply to an external module, and a wearable terminal including it. - Google Patents

Description

The present invention relates to a device for controlling the power supply to an external module, and more particularly to such a device that can be incorporated in a wearable terminal.

In recent years, a monitoring system has been proposed that monitors the source of radio waves by transmitting information such as location information and entry / exit management obtained by devices such as GPS and sensors to an external device as radio waves using electrical energy. There is. Wireless communication modules are responsible for transmitting such radio waves, and for example, Bluetooth (registered trademark) communication modules and Wi-Fi (registered trademark) communication modules are known.

Also, in sporting events such as the Olympic Games that are held for a long time, many volunteers and guards support the event as staff, and it has been considered to manage such a large number of staff with the monitoring system as described above. .. Especially in such a case, it is not realistic to give the staff a bulky wireless communication terminal, and it is assumed that the staff will be given a portable small wireless communication terminal such as a card type or an emblem type.

Generally, such a wireless communication terminal consumes a large amount of power even if it is small, and therefore requires power supply from a primary battery or a commercial power source. For this reason, there is always the need to worry about running out of batteries, replacing the primary battery, and charging from a commercial power source. In order to alleviate such problems, various wireless communication terminals and power supply circuits equipped with a power supply circuit having a function of generating electric power from environmental energy such as light and radio waves have been studied (Patent Documents 1 to 4). ).

Japanese Unexamined Patent Publication No. 2013-188019 Japanese Unexamined Patent Publication No. 2014-087082 Japanese Unexamined Patent Publication No. 2014-166012 Japanese Unexamined Patent Publication No. 2016-146156

However, there are problems that cannot be solved by the above-mentioned conventional techniques. In the above-mentioned Patent Documents 1 to 4, various power supply circuits including an energy harvester element (solar cell or the like) and a secondary battery for storing the power from the energy harvester element are proposed. However, when the environmental energy is insufficient, for example, at night or in a dark toilet, the power supply circuit according to the prior art does not function sufficiently due to the power shortage, and the recovery from the power shortage state should be performed appropriately. There is a problem that it cannot be done. For this reason, the problem that the power supply cannot be properly managed in response to changes in the surrounding environment can be solved in applications where users equipped with the power supply circuit according to the conventional technology are placed in various surrounding environments. There wasn't. Further, in the power supply circuit according to the prior art, even if a plurality of power generation units are included, the problem that the power consumption obtained from one of the power generation units cannot be saved has not been solved yet.

In order to solve the above-mentioned problems, in the embodiment of the present invention, it is possible to provide an apparatus for controlling the power supply to the external module. The device is
The first power supply and
A second power source that includes a power storage element for energy harvesting,
A power supply port configured to supply power from the first power source or the second power source to the external module to start and operate the external module.
A monitor port configured to allow the external module to detect the voltage of the second power supply.
When the voltage of the second power supply is boosted to be equal to or higher than the first lower limit threshold value, the second power supply is connected to the power supply port, and the voltage of the second power supply is the first upper limit. A control unit configured to separate the second power supply from the power supply port when the voltage is stepped down to be equal to or lower than the threshold value.
Includes and includes a feedback section configured to receive instructions from the external module based on the voltage of the second power source detected by the external module via the monitor port.
When the second power supply is separated from the power supply port by the control unit, the voltage of the second power supply detected via the monitor port is stepped down so as to be equal to or less than the second lower limit threshold value. When the feedback unit is used, the feedback unit separates the first power supply from the power supply port and shuts down the external module.

In a preferred embodiment, the device is further configured to connect or detach the second power source to or away from the monitor port based on the voltage applied to the power supply port. May include parts.

In a preferred embodiment, in the above device, the first power source may include a primary cell and the second power source may include a solar cell. Further, the capacitance of the energy harvesting power storage element included in the second power source may be 15 mF or less.

In a preferred embodiment, the device may further include an LED (light emitting diode) for discharging the excess current when the energy harvesting storage element is fully charged.

In a preferred embodiment, a wearable terminal including the above-mentioned device and an external module such that power supply is controlled from the above-mentioned device can also be provided.

According to the apparatus according to the embodiment of the present invention, even when the user is placed in various ambient environments, electric power can be stably supplied in response to changes in the ambient environment, and power consumption is saved. It will also be possible to do.

It is a block diagram which shows the structure of the apparatus 100 which concerns on embodiment of this invention. It is a block diagram which shows the structure of the specific example 200 of the apparatus which concerns on embodiment of this invention. It is a flowchart for demonstrating operation of apparatus 200. It is a block diagram which shows the structure of the specific example 400 of the apparatus which concerns on another Embodiment of this invention. It is a time chart for explaining the operation of the apparatus 400. It is a time chart for explaining the operation of the apparatus 400.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. The same or similar parts in each drawing are designated by the same or similar reference numerals. In the present specification, the word "voltage" may be used for convenience to mean "difference voltage (between a certain two points)" or "potential with reference to GND".

[Basic device configuration]
FIG. 1 is a block diagram for showing an outline of the apparatus 100 according to the embodiment of the present invention. The device 100 is configured to be able to power the external module 199 (shown by the dotted line) that is not included in the device 100. Examples of such external modules include, but are not limited to, wireless communication modules (such as Bluetooth communication modules and Wi-Fi communication modules) and microprocessors. The device 100 includes a first power source 110 and a second power source 120 as power sources, and the second power source 120 has an energy harvesting element 122.

The type of the first power source 110 is not particularly limited, but in order for the device 100 to function even in an environment where the energy harvesting element 122 of the second power source 120 cannot generate power (for example, at night), a primary battery is included. It is preferable to be. Further, the first power source 110 may be a secondary battery including another energy harvesting element, or may include a combination of a primary battery and a secondary battery.

The second power source 120 preferably includes a secondary battery that can be charged by the energy harvesting element 122, or may include a combination of the secondary battery and the primary battery. The capacitance of such a secondary battery is not particularly limited, but it can function even if it is as small as 15 mF or less, preferably 10 mF or less, and more preferably 5 mF or less, and the size of the device 100 is small. It can contribute to the conversion.

In a preferred embodiment, the first power source 110 uses only the primary battery as the battery, and the second power source 120 uses only the secondary battery as the battery, for the purpose of keeping the weight and volume of the entire apparatus 100 small. Each may be included.

The energy harvesting element 122 is not particularly limited as long as it can generate power by capturing environmental energy, but for example, elements such as a solar cell, an antenna coil (which can generate power by radio waves of a specific frequency), and a wind power generator can be used. It may be included. In a preferred embodiment, the energy harvesting element 122 may include a solar cell (PV, PhotoVoltarics) from the viewpoint of facilitating the use of the apparatus 100 outdoors in the daytime.

The device 100 further includes a feedback section 130 to which the first power supply 110 is connected. The feedback unit 130 can receive an instruction from the external module 199, and the first power supply 110 can be connected to or separated from the power supply port 150 described later according to the instruction.

Instructions received by the feedback unit 130 from the external module 199 can be created and transmitted by the external module 199 by any means. In one embodiment, for convenience, feedback is continuously provided while the external module 199 is booting, and the feedback signal is obtained via the monitor port 160 described below. It may be expressed as a voltage equal to a voltage of 120. In another embodiment, the feedback from the external module may be intermittently provided at predetermined time intervals. In yet another embodiment, the feedback signal may or may be the result of some correction (addition, subtraction, etc.) to the voltage of the second power supply 120 obtained through the monitor port 160. It may be some other signal to represent the voltage.

As an example of the instruction fed back from the external module, for example, the one expressed by High / Low (H / L, high / low) of the voltage as a feedback signal can be mentioned. In some embodiments, the feedback signal (voltage) from the external module may be configured to be connected (ON) when it is high (High) and separated (OFF) when it is low (Low). Alternatively, it can be configured to perform the opposite operation. The voltage threshold value for switching H / L can be arbitrarily set within a category suitable for the operation of the component / element group of the device 100. In the initial state of the device 100 (power supply from the second power supply 120 to the external module 199 has not started), the feedback unit 130 separates the first power supply 110 from the power supply port 150. This is preferable for saving the power consumption of the first power supply 110, that is, it is preferably ON when it is High and OFF when it is Low.

The feedback unit 130 may include switching elements, and any means known in the art, such as relays, field effect transistors (FETs), and programmable logic controllers (PLCs), may be used to mount such switching elements. Can be done. For example, it is possible to mount a switching element by a combination of a FET having a predetermined performance and a resistor, and set an ON / OFF threshold value appropriately. The same applies to the switching elements of the control unit 140 and others described later.

The appliance 100 further includes a control unit 140 to which the second power supply 120 is connected. The control unit 140 can connect or disconnect the second power supply 120 to or separate from the power supply port 150 described later, based on the magnitude of the voltage of the second power supply 120. The operation of the control unit 140, unlike the feedback unit 130, is not directly instructed by the external module 199. That is, the control unit 140 can be regarded as a switching element that functions autonomously (completely in the device 100).

More specifically, the voltage of the second power source 120 becomes the first lower limit due to the increase in the amount of power generated by the energy harvesting element 122 (for example, by placing the device 100 in a bright ambient environment). When boosted above the threshold, the control unit 140 can connect the second power source 120 to the power supply port 150. This first lower threshold can be arbitrarily set in a category appropriate for the operation of the component / element group of the device 100. In a preferred embodiment, after the control unit 140 connects the second power source 120 to the power supply port 150, the feedback unit 130 receives feedback from the activated external module 199 to power the first power source 110. Can operate to connect to supply port 150. By such an operation, the external module 199 can be started by the power of the second power source 120 that generates energy for the environment, and the power consumption of the first power source 110 can be suppressed. This effect is beneficial because it generally consumes a relatively large amount of power when the external module 199 starts up.

In addition, the voltage of the second power source 120 becomes less than or equal to the first upper threshold value due to the decrease or disappearance of the power generation amount of the energy harvesting element 122 (for example, when the device 100 is placed in a low brightness ambient environment). When stepped down to, the control unit 140 can separate the second power supply 120 from the power supply port 150. This first upper threshold can also be set arbitrarily within the scope appropriate for the device 100. By such an operation, the power supply from the first power supply 110 can be prioritized, and the power supply to the external module 199 can be prevented from suddenly becoming insufficient due to changes in the surrounding environment. In other words, the voltage drop of the second power source 120 that generates energy can be compensated by the first power source 110 to prevent sudden malfunction / shutdown of the external module 199.

Returning to the feedback unit 130, the feedback unit 130 further powers the first power supply 110 when the second power supply 120 is separated from the power supply port 150 by the control unit 140. It also works away from port 150. More specifically, when the second power supply 120 is separated from the power supply port 150 by the control unit 140 (that is, when the voltage of the second power supply 120 is below the second lower limit threshold value). When the voltage of the second power supply 120 detected via the monitor port 160 described later is stepped down so as to be below a predetermined lower limit threshold value, the feedback unit 130 separates the first power supply 110 from the power supply port 150. By doing so, the external module 199 can be shut down. By doing so, the change in the power generation amount of the second power supply 120, which is affected by the surrounding environment, does not immediately lead to the malfunction / shutdown of the external module, and the power consumption of the first power supply 110 is also increased. It is possible to obtain the remarkable effect of saving. This second lower threshold can also be set arbitrarily within the scope appropriate for the device 100.

The appliance 100 also has a power supply port 150. The power supply port 150 is one of the ports for connecting the device 100 to the external module 199, and the connection style of such ports can be set arbitrarily. It is responsible for supplying power from the first power supply 110 or the second power supply 120 to the external module 199 through the power supply port 150.

Device 100 also has a monitor port 160 that connects to a second power supply 120. Through this monitor port 160, device 100 can be connected separately to external module 199. The monitor port 160 allows the external module 199 to monitor the voltage of the second power supply 120 and to operate in response to that voltage. For example, when the voltage of the second power supply 120 is above a certain threshold value, the external module 199 performs frequent processing (such as wireless communication), and when the voltage of the second power supply 120 is below a certain threshold value, the processing frequency is set. By dropping it, it is possible to save power consumption.

In FIG. 1, the power supply port 150 and the monitor port 160 are drawn as separate parts, and the port connected to the feedback unit 130 is omitted, but this is just an example. Multiple or all of the ports (not shown) to which the power supply port 150, the monitor port 160, and the feedback unit 130 are connected may be physically mounted as a single terminal. By saving the physical size of the terminals in this way, it is possible to promote the miniaturization of the device 100.

In certain embodiments, not only the device 100 described above, but also a terminal including such a device 100 and an external module can be provided. Such terminals are preferably small (tablets, smartphones, etc.), so-called wearable terminals (card type, name tag type, emblem type, wristwatch type, wristband type, earphone type, seal type, clothing type, eyeglass type, etc.) It is more preferable that the terminal is worn by the user.

[First specific example of device configuration]
FIG. 2 is a block diagram showing a device 200 as an example of mounting the above-mentioned device 100 as a concrete circuit. Unless otherwise stated, the operation of device 200 is in accordance with device 100. In FIG. 2 and FIG. 4 described later, the arrow directed to the switch portion means that the switch portion is turned ON / OFF based on the voltage at the base of the arrow. The device 200 also has the ability to power external modules (not shown) not included in the device 200. As an example of the combination of power sources in the present invention, the device 200 described here has a primary battery circuit 210 and a storage circuit 220 (secondary battery) connected to the solar cell 222 as a power source.

The device 200 and the external module are connected via a power supply port 250, a monitor port 260, and a port for receiving feedback (not shown).

The device 200 has a second switch section (SW2) 230 that is responsible for connecting or separating the primary battery circuit 210 and the power supply port 250. The second switch unit 230 can switch between opening and closing by receiving feedback from an external module (voltage H / L, etc.). Further, it is preferable to provide a diode 232 for backflow prevention between the second switch section 230 and the power supply port 250.

The device 200 also has a power control circuit 240 that is responsible for connecting or separating the solar cell 222 and the power storage circuit 220 from the power supply port 250. The power control circuit 240 preferably includes a first switch section (SW1) 242 and a diode 244. The power supply control circuit 240 can detect the difference voltage between the power storage circuit 220 and the ground line (GND) 270, and switch the first switch unit 242 according to the difference voltage.

FIG. 3 is a flowchart for explaining the operation of the above-mentioned device 200. For ease of explanation, it is assumed that the device 200 does not supply power to the external module (EXM) and starts from the initial state that the external module is not started.

In step S300, the device 200 receives light, the solar cell 222 starts to generate electricity, the storage circuit 220 is charged, and its voltage rises.

When the voltage of the power storage circuit 220 is boosted beyond the first lower threshold in step S310, the power control circuit 240 turns on the first switch unit 242, and the power storage circuit 220 is connected to the power supply port 250.

Step S320 prepares to boot an external module powered by power storage circuit 220 through power supply port 250. The external module activated at this time can know the voltage of the power storage circuit 220 via the monitor port 260.

Step S330 activates the external module to perform certain functions such as wireless communication.

In step S340, when the amount of power generated by the solar cell 222 decreases or disappears due to changes in the ambient environment and the voltage of the power storage circuit 220 falls below the first upper limit threshold, the power control circuit 240 turns off the first switch section 242. The power storage circuit 220 is separated from the power supply port 250.

In step S350, the external module monitoring the voltage of the storage circuit 220 through the monitor port 260 confirms the instruction (voltage) to be fed back to the second switch 230 of the device 200. In this example, for the sake of clarity, it is assumed that feedback is performed while the external module is operating, and the feedback instruction is expressed by voltage. The feedback voltage shall be equal to the voltage of the storage circuit 220 monitored via monitor port 260.

If the potential fed back from the external module is equipotential with the power supply port 250 and is non-zero, proceed to step S360, turn on the second switch 230, and connect the primary battery circuit 210 to the power supply port 250. Then return to step S340.

When the feedback voltage from the external module becomes zero (equal to GND, the voltage of the power storage circuit 220 becomes zero), proceed to step S370, turn off the second switch 230, and the primary battery circuit. Isolate 210 from power port 250 and shut down the external module. At this time, it should be noted that the voltage of the primary battery circuit 210 does not have to be zero. In other words, when the voltage of the power storage circuit 220 becomes zero (the amount of charge is empty), the power supply to the external module can be stopped and shut down so that the voltage of the primary battery circuit 210 remains. .. Such an operation can save the power consumption of the primary battery circuit 210 and significantly reduce the frequency of replacement of the primary battery circuit 210 (charging when the secondary battery is also included). Moreover, the shutdown of the external module does not occur as soon as the power generation of the solar cell 222 has diminished / stopped, but can be caused with a certain grace period after the power generation has diminished / stopped. This makes it possible to avoid failures of external modules that are vulnerable to sudden shutdown. In certain embodiments, the external module may be prepared to shut down (such as transitioning to system hibernation) prior to turning off the second switch 230 in step S370.

This completes the series of operations of the device 200 and returns to the initial state. The device 200 also has a function as a reset circuit capable of returning to the initial state in this way. With such a function as a reset circuit, the user does not have to take the trouble of restarting the external module, and the external module is automatically started and shut down appropriately in response to changes in the surrounding environment. From a different point of view, by making the solar cell 222 function like an optical sensor and monitoring it, the power consumption of the primary battery circuit 210 can be minimized. Such an effect cannot be obtained by the conventional technique of using the primary battery simply as an auxiliary to the secondary battery.

In yet another embodiment, a period / condition in which the device 200 does not receive feedback from the external module may be intentionally provided. For example, only when the voltage of the power storage circuit 220 obtained from the monitor port 260 is high enough, the feedback signal is stopped, the second switch 230 (SW2) is turned off, and the primary battery circuit 210 is connected from the power supply port 250. By keeping them apart, the power consumption of the primary battery circuit 210 can be further reduced. Alternatively, by configuring the external module or device 200 to have a timekeeping means (not shown) so that the SW2 is turned off after a certain period of time has passed since the SW2 was turned on, the primary battery circuit 210 The power consumption may be further reduced.

[Second specific example of device configuration]
FIG. 4 is a block diagram showing the device 400 as another example of mounting the device 100 as a concrete circuit. The device 400 is the same as the device 200 above, and a duplicate description is omitted, but a third switch unit (SW3) 446 for connecting or separating the storage circuit 420 and the monitor port 460 is provided, and the power is provided. The difference is that the power storage circuit 420 also has an LED 424, which is opened and closed according to the potential of the supply port 450. By adopting such a configuration, it is possible to suppress the occurrence of a problem due to the constant connection between the external module in the non-started state and the power storage circuit 420. For example, if the part of the external module that is not started and is connected via the monitor port 460 is treated as GND, the power storage circuit 420 will not be charged even if the solar cell 422 starts to generate electricity. However, even in such a case, the problem can be avoided by turning off the third switch part 446. It is also possible to discharge the excess current by making the LED 424 emit light when the power storage circuit 420 is fully charged. Such an LED 424 can also serve to inform the user that the power storage circuit 420 is fully charged.

The device 400 behaves basically the same as the device 200 in Figure 3, but at the point corresponding to step S320, the connection to the monitor port 460 is when the voltage of the power storage circuit 420 is high (for example, from zero). It is supposed to be done when it is high).

5 and 6 are time charts for explaining the operation of the device 400, respectively. The vertical axis represents voltage and the horizontal axis represents time.

First, FIG. 5 describes an operation example when there is no feedback from the external module (SW2 remains OFF without considering the feedback).

When the device 400 receives light and the solar cell 422 starts to generate electricity and the voltage of the power storage circuit 420 rises, the power control circuit 440 turns on SW1 when the threshold value is exceeded. Then SW3 is turned on and the monitor port 460 is connected to the power storage circuit 420. Power is supplied from the power storage circuit 420 to operate the external module. Since feedback from the external module is not considered here, the primary battery circuit 410 remains isolated from the power supply port 450. Therefore, when the voltage of the power storage circuit 420 drops and SW1 is turned off, the external module shuts down immediately.

FIG. 6 describes an operation example when feedback from an external module is received (SW2 is turned ON / OFF according to the feedback). It is the same as Fig. 5 up to the middle, except that SW2 is turned on and the primary battery circuit 410 is connected to the power supply port 450 when the external module starts up and gives feedback. After that, even if the voltage of the power storage circuit 420 drops and SW1 turns off, SW2 remains on for a while, turns off after a predetermined time, and shuts down the external module relatively slowly. be able to.

It will be apparent from the description herein that the device 200 also operates in much the same manner as described above, except for the presence of SW3 for the connection / separation of the monitor ports.

The embodiments of the present invention described above are merely examples, and mounting examples of the device can be configured by various circuits and various components / elements. For example, although the description of the existence of elements such as resistors and capacitors is omitted above, it has been read through this specification that these elements may be included in the configuration of the device as needed. If you are a trader, you will understand.

100 equipment
110 primary power supply
120 Second power supply
122 Energy harvesting element
130 Feedback section
140 Control unit
150 power supply port
160 monitor port
199 External module
200 equipment
210 Primary battery circuit
220 Power storage circuit
222 solar cells
230 Second switch (SW2)
232 diode
240 power control circuit
242 First switch section (SW1)
244 diode
250 power supply port
260 monitor port
270 ground line (GND)
400 equipment
410 Primary battery circuit
420 power storage circuit
422 solar cell
424 LED
430 Second switch section (SW2)
432 diode
440 power control circuit
442 First switch section (SW1)
444 diode
446 Third switch section (SW3)
450 power supply port
460 monitor port
470 Ground line (GND)

Claims (7)

It is a device for controlling the power supply to the external module.
The first power supply and
A second power source that includes a power storage element for energy harvesting,
A power supply port configured to supply power from the first power source or the second power source to the external module to start and operate the external module.
A monitor port configured to allow the external module to detect the voltage of the second power supply.
When the voltage of the second power supply is boosted to be equal to or higher than the first lower limit threshold value, the second power supply is connected to the power supply port, and the voltage of the second power supply is the first upper limit. A control unit configured to separate the second power supply from the power supply port when the voltage is stepped down to be equal to or lower than the threshold value.
Includes a feedback section configured to receive instructions from the external module based on the voltage of the second power source detected by the external module through the monitor port.
When the second power supply is separated from the power supply port by the control unit, the voltage of the second power supply detected via the monitor port is stepped down so as to be equal to or less than the second lower limit threshold value. The apparatus, wherein the feedback unit separates the first power source from the power supply port and shuts down the external module. 1. Device. The device according to claim 1 or 2, wherein the first power source includes a primary battery. The apparatus according to any one of claims 1 to 3, wherein the second power source includes a solar cell. The device according to any one of claims 1 to 4, wherein the energy harvesting power storage element included in the second power source has a capacitance of 15 mF or less. The apparatus according to any one of claims 1 to 5, further comprising an LED for discharging an excess current when the energy harvesting power storage element is fully charged. A wearable terminal including the device according to any one of claims 1 to 6 and the external module.

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