JP7436592B2 - Wearable devices and their batteries and power supply systems - Google Patents

Description

The present invention relates to a technology for contactless power supply to wearable devices such as head-mounted displays (hereinafter referred to as HMDs).

The following technologies are known as non-contact power supply technologies for wearable devices worn on the user's body.

Patent Document 1 relates to electronic eyeglasses having variable focus lenses and a charging device for the same, in which the charging device is fitted into the modern part of the electronic eyeglasses, and power is transmitted from the power transmitting coil of the charging device to the power receiving coil of the electronic eyeglasses by electromagnetic induction. A configuration for charging a driving battery of electronic eyeglasses is disclosed.

Patent Document 2 relates to a wearable device that includes a heating unit that warms the front part of the eye, which is placed in front of the user's eyes, and in which an electric wire wound around the front of the eye generates heat to warm the front part of the eye, and the electric wire is connected to the outside of the eye. A configuration is disclosed in which the power receiving coil receives power supply from the power transmitting coil in a contactless manner.

Patent Document 3 relates to a power supply system from a secondary battery module to an electronic device (for example, a glasses-type device), and a belt portion of the secondary battery module includes a flexible secondary battery and a non-contact power transmission. Disclosed is a configuration in which a power transmitting unit for generating power and a flexible thermoelectric power generation device are housed, and power is transmitted from the power transmitting unit of a secondary battery module to a power receiving unit included in an electronic device by non-contact power transmission.

JP2009-251068A JP2016-032213A Japanese Patent Application Publication No. 2016-073196

In recent years, HMDs have come to play the role of wearable computers, smartphones, and tablets. In addition, glasses-type transparent HMDs are augmented reality (AR)
Immersive HMDs are considered important as core devices for virtual reality (VR). Sometimes people use HMDs to enjoy movies and games.

However, as HMDs become more sophisticated, power consumption increases, and the usable time becomes insufficient with the conventional installed battery capacity, making it impossible to continue using the HMD while it is attached. The user has to deal with this problem by connecting the HMD to an external power source with a cable and charging it, or by stopping the use of the HMD and charging the battery, which can be inconvenient for the user. In order to continue using the HMD while it is attached, it is only necessary to increase the capacity of the mounted battery, but this increases the weight. In particular, since glasses-type HMDs, like regular glasses, put the weight of the device on the user's ears and nose, the increase in weight must be suppressed as much as possible so as not to impair the feeling of wearing the device. Further, like mobile terminals, HMDs have become smaller and thinner, but on the other hand, cable connections during charging or use are cumbersome, and users are increasingly demanding a simple charging method. As described above, being able to continue using the device while wearing it and eliminating the hassle of cable connections are important issues for wearable devices that are always worn and used.

In Patent Document 1, in order to charge the driving battery of the electronic glasses, the user performs an operation of fitting the portable charging device into the modern part of the electronic glasses, but there is no need to attach or remove the portable charging device. During this process, the electronic glasses may move, or the electronic glasses may have to be temporarily removed from the head, resulting in a temporary interruption in the use of the electronic glasses. That is, it seems difficult for the user to continue using the electronic glasses while wearing them. Note that Patent Document 1 also describes a method in which a portable charger is connected to an external power source while remaining attached to the modern part of electronic glasses for charging, but the problem of the troublesome cable connection remains. Furthermore, since the portable charging device is connected to the charger through an external terminal, it has a terminal that is exposed to the outside, and when the portable charging device is worn on the head, there are concerns about short circuits due to sweat and corrosion of the terminals.

Patent Document 2 describes that an electric wire wound around the front of the eye of a wearable device serves as a power receiving coil, and receives power from an external power transmitting coil in a contactless manner. At this time, in order to receive the desired power supply from the external power transmitting coil, the distance between the power transmitting coil and the power receiving coil must be close. This is to suppress radio wave leakage to the surroundings within an allowable value during power transmission. As described in Patent Document 2, when electronic glasses are placed on a charging stand or the like and the power transmitting coil and the power receiving coil are close to each other, desired power transmission is possible. However, when a user wears and uses a wearable device, the external power transmitting coil must be placed close to the front of the eye (the position of the power receiving coil), which obstructs the user's field of vision when using the wearable device. That is, it is expected that sufficient power cannot be supplied when the wearable device is worn by the user.

In Patent Document 3, an electronic device (glasses type device) is configured to receive power in a non-contact manner from a belt-shaped secondary battery module worn on the waist. In this case as well, considering the distance from the user's waist to the head, it is expected that it will be difficult to supply the power consumed by a glasses-type device such as an HMD. Further, Patent Document 3 states that the secondary battery can be charged from the terminal portion via a cable, but as described above, charging via the cable is troublesome for the user.

SUMMARY OF THE INVENTION In view of the above-mentioned problems of the prior art, an object of the present invention is to provide a wearable device that can supply the power necessary to drive the device while the wearable device is attached and in use, and is less troublesome for the user during use.

To give an example of the present invention, a wearable device is equipped with at least first and second batteries, and includes a plurality of power receiving units that receive power from the first and second batteries by wireless transmission. a power management unit that monitors the states of the first and second batteries installed; a communication unit that performs wireless communication between the first and second batteries installed; and a display that provides information to the user. and a plurality of limiting units that limit the power received by the plurality of power receiving units, and a control unit that controls the power receiving unit, the power management unit, the communication unit, the display, and the limiting unit. . The control unit limits the power supplied to the load via the limiting unit according to the power usage status of the load in the wearable device, and the power management unit is configured to control the wearable device via the communication unit. The present invention is characterized in that information on the remaining amount of stored power of the first and second batteries is acquired, and the obtained information on the amount of remaining stored power is displayed on the display.

Furthermore, the plurality of limiting units have a function of preventing reverse current from flowing to the first and second batteries, and the power management unit is configured to control the amount of remaining power stored in the first battery in use. When determining that it is smaller than the threshold, the control unit controls the reverse current prevention function of the limiting unit to prevent the power receiving system from the first battery in use to the second battery in standby. At the same time, a warning prompting the user to replace the first battery in use is displayed on the display.

The battery of the present invention can be attached to a wearable device to supply power and can be charged with a charger, and includes a storage battery unit that stores power, and transmits power from the storage battery unit to the wearable device by wireless transmission. a power transmission/reception unit that receives power from the charger to charge the storage battery unit; a conversion unit that converts direct current to alternating current between the storage battery unit and the power transmission/reception unit; a power storage state recognition unit that detects and holds the remaining power storage amount of the storage battery unit or power storage state information; a communication unit that performs wireless communication between the wearable device and the charger; the power transmission/reception unit; and the power storage state recognition unit. and a control unit that controls the communication unit, and the power storage state recognition unit transmits information on the remaining power storage amount of the storage battery unit to the wearable device via the communication unit, and transmitting power storage state information of the storage battery unit to the device, and upon receiving a control command from the wearable device via the communication unit, the control unit stops power transmission from the storage battery unit to the wearable device. Features.

Further, the power supply system of the present invention includes a wearable device, a battery that supplies power to the wearable device, and a charger that charges the battery. The wearable device is equipped with at least a first and a second battery, and includes a plurality of power receiving units that receive power from the first and second batteries by wireless transmission, and a plurality of power receiving units that are equipped with at least a first and a second battery. a power management unit that monitors the state of the battery and a third battery being charged by the charger; and a communication unit that performs wireless communication between the attached first and second batteries and the charger. , a display that provides information to a user. The first to third batteries include a first storage battery unit that stores power, and transmit power from the first storage battery unit to the wearable device by wireless transmission, and charge the first storage battery unit. a power transmitting/receiving unit that receives power from the charger, a power storage status recognition unit that detects and holds the remaining power storage amount of the first storage battery unit or information on the power storage status during charging, the wearable device and the A communication unit that performs wireless communication with the charger. The charger includes a second storage battery section that stores power, a power transmission section that transmits power from the second storage battery section to the third battery that is being charged by wireless transmission, and a power transmission section that transmits power from the second storage battery section to the third battery that is being charged. A charging battery monitoring unit that acquires information on the storage state of the battery, and a communication unit that performs wireless communication between the wearable device and the third battery. The wearable device displays, on the display, information on the amount of remaining power storage obtained from the first and second batteries that are attached, and information on the state of power storage of the third battery that is being charged and obtained from the charger. and when it is determined that the remaining power storage amount of the first battery in use is smaller than a threshold, the power receiving system is switched from the first battery in use to the second battery in standby. At the same time, a warning prompting the user to replace the first battery in use is displayed on the display.

According to the present invention, the user can replenish the necessary power while wearing the wearable device, and can continue to use the device. For example, even when a user watches a movie for a long time, increasing the number of batteries installed will not affect the fit, and there will be no need to worry about connecting a power supply cable from the terminal of the wearable device to an external power source. Improved usability.

FIG. 1 is a diagram showing the overall configuration of a power supply system including an HMD, a battery, and a charger (Example 1). A block diagram showing the internal configuration of the HMD 100. FIG. 2 is a block diagram showing the internal configuration of a battery 200. FIG. 3 is a block diagram showing the internal configuration of a charger 300. A diagram showing power transmission between the HMD 100 and batteries 200a and 200b in use. FIG. 3 is a diagram showing power transmission between a charging battery 200c and a charger 300. A diagram showing communication between an HMD, a battery in use, and a charger. A diagram showing communication between the HMD, the charging battery, and the charger. The figure which shows the example which displayed the various function menu of HMD on the display. The figure which shows the example which displayed the battery status on a display. A diagram showing data transmission between the power supply system and the cloud. A diagram showing control of power transmission between an HMD and a battery (Example 2). 10 is a flowchart showing a process for removing a battery in use from an HMD. A flowchart showing the process of switching a battery in use to a battery in standby. A flowchart showing the process when the battery is removed from the HMD. FIG. 7 is a diagram showing the operation of attaching a battery to an HMD and a charger (Example 3). The figure which shows the example of the electric power system circuit in a battery. The figure which shows an example of the internal structure of a battery. The figure which shows the state when a battery is attached to HMD. The figure which shows another example of a battery internal structure. The figure which shows the modification of FIG. 17. FIG. 4 is a diagram showing the configuration of a charger 400 that charges a battery attached to an HMD. FIG. 7 is a diagram showing the configuration of a power supply system that supplies power to the HMD not only from the battery but also from the charger 500 (Embodiment 4). 20A is a diagram illustrating a specific application example of the power feeding system of FIG. 20A. FIG.

Hereinafter, embodiments of the present invention will be described in detail using the drawings. However, the present invention should not be construed as being limited to the contents described in the embodiments shown below. Those skilled in the art will readily understand that the specific configuration can be changed without departing from the spirit or spirit of the present invention. In the configuration of the invention described below, the same parts or parts having similar functions may be designated by the same reference numerals in different drawings, and overlapping explanations may be omitted.

Embodiment 1 In Embodiment 1, a basic configuration of power supply to a wearable device according to the present invention will be described. A glasses-type head-mounted display (hereinafter referred to as HMD) will be taken up as an example of a wearable device that is worn on the user's body. The HMD is equipped with multiple batteries, and when the battery in use runs out of power, it is removed from the HMD and charged with a charger. While the battery is being charged, power is supplied to the HMD by switching to another battery that is on standby, so the user can continue to use the HMD. At this time, power is transmitted wirelessly (non-contact) between the HMD and the battery, and between the battery and the charger, and information such as the remaining battery power and charge amount is transmitted to each other through communication.

FIG. 1 is a diagram showing the overall configuration of a power supply system including an HMD 100, a battery 200, and a charger 300. First, the basic operations will be explained. The glasses-shaped HMD 100 has power receiving units 102a and 102b in the symmetrical temple portion (temple part 114) of the glasses, and two batteries 200a and 200b are attached thereto. Power is supplied from the batteries 200a, 200b to the power receiving units 102a, 102b via power transmitting/receiving coils. Here, the configuration is such that two batteries are installed, but of course, two or more batteries may be installed.

When one battery 200a becomes insufficient in remaining capacity due to use of the HMD 100, a warning of insufficient remaining capacity is displayed on the display 119 of the HMD 100. The user removes the battery 200a from the power receiving unit 102a and inserts it into the charging slot 311 (four slots 311a to 311d in this example) of the charger 300. During that time, the HMD 100 switches to the other battery 200b that is on standby and continues operating.

In the charging operation from the charger 300 to the battery 200a, power is also supplied via the power transmission/reception coil. When charging of the battery 200a is completed, the display section of the HMD 100 indicates the completion of charging, and the user takes out the battery 200a and attaches it to the power receiving section 102a of the HMD 100. In this way, a plurality of batteries are attached to the HMD 100 and used by switching them alternately, so the user can continue to use the HMD 100. However, since the work of replacing the battery 200 with respect to the HMD 100 and the work of inserting it into the charger 300 are performed with the user wearing the HMD 100, the following measures have been taken.

Immediately behind the power receiving section 102a to which the battery 200 is attached in the HMD 100, an infrared sensor 115a is installed toward the outside of the temple section. Furthermore, an infrared sensor 115b is similarly installed in the power receiving unit 102b on the opposite side. When the user wants to remove the battery 200a attached to the power receiving section 102a, the user can easily remove the battery 200a by inserting his or her finger into a recess at the rear end of the power receiving section 102a. At this time, the infrared sensor 115a located near the rear end of the power receiving unit 102a detects that a hand approaches to remove the battery 200a. If the user accidentally attempts to remove the battery 200b (right eye side) instead of the battery 200a (left eye side), the infrared sensor 115b installed near the power receiving unit 102b on the right eye side detects the approach of the user's hand. By detecting this and issuing a warning that the battery that should be replaced is the battery for the left eye rather than the right eye, it is possible to prevent the user from operating incorrectly.

Next, the user inserts and installs the removed battery 200a into one of the plurality of charging slots 311a to 311d of the charger 300. Slot number portions 312a to 312d corresponding to each charging slot have a convex structure in the form of a number, and the user can touch them with a finger to recognize the slot number and the orientation of the charger. Note that in the slot number portion 312, a red LED lights up when charging of the battery starts, and a green LED lights up when charging is completed. The same applies to the battery 200 inserted into the charging slot 311; when charging starts, the red LED 215 lights up, and when charging is completed, the green LED 215 lights up.

Further, the glasses-type HMD 100 can be attached to and removed from the head by expanding the temple portion. Strain sensors 116a and 116b are provided at the end of the temple section on the display section side, and by detecting the spread of the HMD when it is worn by the strain sensors 116a and 116b, it can be determined that the HMD has been removed from the head. If the detection signals of the strain sensors 116a and 116b do not change for a predetermined period of time (for example, one minute), the HMD 100 automatically enters standby mode, and when the detection signals change again, the HMD operation is started. This allows the power consumption of the HMD 100 to be saved. A camera 120 and an infrared sensor 115c are provided on the front side of the HMD 100.
Next, the respective configurations of HMD 100, battery 200, and charger 300 will be explained.

FIG. 2 is a block diagram showing the internal configuration of the HMD 100. The HMD 100 includes a control section 101, a memory section 105, a power management section 106, a sensor section 107, a communication section 108, a data output section 109, and a data input section 110. The control unit 101 controls the overall operation of the HMD 100.

The memory unit 105 stores information on the internal state of the HMD 100 and information on the power storage state of the battery 200, and also stores image data to be displayed on the HMD. The power management section 106 includes a power reception section 102, a conversion section 103, and a restriction section 104 for receiving power from the battery 200 in use, and supplies power to each section within the HMD 100. The power receiving unit 102 includes a power receiving coil for wirelessly receiving power. The power management unit 106 also monitors the status of the battery 200 being used by the HMD 100, the battery 200 being charged by the charger 300, and the built-in battery. The frequency counter 121 detects that the battery 200 in use is removed. Details of these operations will be described later.

The sensor unit 107 includes an infrared sensor 115 and a strain sensor 116, and may also include an acceleration sensor, a gyro sensor, a magnetic sensor, a temperature sensor, an electrostatic sensor, a tactile sensor, etc. as necessary. The communication unit 108 includes a wireless LAN or Bluetooth (registered trademark) for wireless communication with the battery 200 and the charger 300, and may also include a position information acquisition function using a GPS (Global Positioning System) and a One Seg function.

The data output unit 109 includes a display 119 that displays images and information to be provided to the user at the position of the lens portion of the glasses, a speaker (earphone) that outputs audio, a light emitting element, and the like. The data input unit 110 includes a camera 120 that photographs the scenery in front of the HMD 100, a microphone that inputs audio, an operation input unit from the user, and the like.

FIG. 3 is a block diagram showing the internal configuration of battery 200. The battery 200 includes a control section 204, a communication section 205, a memory section 206, a storage state recognition section 207, a storage section 208, and a display section 209. Control unit 204 controls the overall operation of battery 200.

The communication unit 205 includes a wireless LAN and Bluetooth (registered trademark) for wireless communication with the HMD 100 and the charger 300. The memory unit 206 can store information on the internal state of the battery 200 and can also store image data to be displayed on the HMD 100.

The power storage state recognition unit 207 detects the remaining power storage amount or charge amount of the battery and holds the information. The power storage unit 208 includes a storage battery unit 201 including a power storage element, a power transmission/reception unit 203 that transmits or receives power between the conversion unit 202, the HMD 100, and the charger 300. The power transmitting/receiving unit 203 has a power transmitting/receiving coil for transmitting and receiving power wirelessly. The display unit 209 is an LED 215 that displays the amount of electricity stored in the battery in a color-coded manner.

In the following description, the battery 200 will be distinguished from 200a to 200d (the same applies to internal elements of the battery) depending on its usage state (in use with an HMD, while charging with a charger).

FIG. 4 is a block diagram showing the internal configuration of charger 300. The charger 300 includes a control section 301, a communication section 302, a memory section 303, a charging battery monitoring section 304, a display section 305, and a power supply section 306. Control unit 301 controls the overall operation of charger 300.

The communication unit 302 includes a wireless LAN and Bluetooth (registered trademark) for wirelessly communicating with the HMD 100 and the battery 200. Furthermore, it may be equipped with a position information acquisition function using GPS and a One Seg function.

The memory unit 303 can store information on the internal state of the charger 300 and information on the power storage state of the battery 200, and can also store image data to be displayed on the HMD 100.

The charging battery monitoring unit 304 acquires information on the amount of charge of the battery 200 that is being charged. The display unit 305 is an LED that displays the start and completion of battery charging in different colors.

The power supply unit 306 includes a storage battery unit 307 that supplies power to the battery 200, a conversion unit 308, and a power transmission unit 309. The power transmission unit 309 includes a power transmission coil for wirelessly transmitting power. Note that the number of display units 305 and power supply units 306 equal to the number of charging slots 311 is provided.

Here, the storage battery section 307 of the power supply section 306 can be charged by an external power source. Then, depending on the usage status of the HMD 100, an external power source is also used. For example, when the HMD 100 is used for a long time while sitting in one place, such as when watching a movie, the power supply section 306 is connected to an external power source such as a commercial power source. On the other hand, when the HMD 100 is carried around, the HMD battery 200 is charged by the charged storage battery section 307.

Note that in FIGS. 2 to 4, the power transmitting unit/power receiving unit includes a power transmitting coil/power receiving coil, and the communication unit includes an antenna, but these are omitted in the drawings for the sake of simplicity.

5A and 5B are diagrams illustrating power transmission between HMD 100, battery 200, and charger 300. 5A shows the power transmission between the HMD 100 and the batteries 200a and 200b in use, and FIG. 5B shows the power transmission between the battery 200c in use and the charger 300.

In FIG. 5A, a plurality of (here, two) batteries 200a and 200b can be attached to the HMD 100, and power can be supplied from each of the batteries 200a and 200b. A direct current flows out from the storage battery units 201a, b of the battery, and is converted into an alternating current of, for example, 150 kHz by the converting units 202a, b. Then, power is wirelessly transmitted from the power transmitting units 203a and 203b (power transmitting coils) to the HMD 100.

The HMD 100 has a plurality of power receiving units 102a and 102b (power receiving coils), each of which receives power wirelessly transmitted at, for example, 150 kHz from batteries 200a and 200b. The converters 103a and 103b convert the received alternating current into a predetermined direct current. The limiting units 104a and 104b supply direct current to the control unit 101, but limit the supplied power depending on the power usage status of the load within the HMD 100. Therefore, the control unit 101 sends a control signal for power restriction to the restriction unit 104 based on the power usage status of the load, but this is omitted in the drawing.

How to use the plurality of batteries 200a and 200b in the HMD 100 can be set by selecting a control sequence performed by the control unit 101, such as preferentially using the one with a smaller amount of remaining power storage. Furthermore, by enabling the power receiving units 102a, b and the converting units 103a, b to perform bidirectional power transmission and power conversion, one power receiving unit, for example 102a, is always equipped with the battery 200a, and the other power receiving unit 102b can be set for exchange only. Thereby, the battery 200b attached to the power receiving unit 102b can supply the power necessary for operating the HMD 100, and it is also possible to set the battery 200a to store the power. In this case, even if one hand cannot be used for some reason, it is possible to continue using the HMD 100 for a long time, which exceeds the usage time with a single battery capacity, while wearing the HMD 100.

In this way, by providing a plurality of batteries, the other battery is working as a power source for the HMD 100 when the battery is replaced, so the HMD can be used continuously even when the battery is replaced. Furthermore, a built-in battery included in the power management unit 106 of the HMD 100 can also be used. Although the built-in battery has a smaller battery capacity than the batteries 200a and 200b that are installed, the battery capacity is sufficient to operate the HMD100 during the battery replacement time, making it possible to continue using the HMD even when the battery is replaced. . However, if the battery is not replaced for a predetermined period of time, the HMD 100 itself is shut down in order to preserve data.

FIG. 5B shows power transmission (charging operation) from charger 300 to battery 200c. In the power supply section 306 of the charger 300, the DC current generated from the storage battery section 307 is converted into alternating current at the conversion section 308, and the power is wirelessly transmitted from the power transmission section 309 (power transmission coil) to the battery 200c being charged. . The power transmitted from the charger 300 is received by the power receiving unit 203c (power receiving coil) in the power storage unit 208 of the battery 200c, converted to direct current by the conversion unit 202c, and stored in the storage battery unit 201c.

6A and 6B are diagrams illustrating communication between HMD 100, battery 200, and charger 300. Of these, FIG. 6A shows communication regarding the battery in use 200a (200b), and FIG. 6B shows communication regarding the battery under charge 200c.

In FIG. 6A, the communication unit 108 of the HMD 100 performs wireless communication with the communication unit 205a of the battery 200a (200b) in use, and the amount of remaining battery power obtained by the power storage status recognition unit 207a of the battery 200a, b in use is The power management unit 106 of the HMD 100 acquires the information. Furthermore, the communication unit 108 of the HMD 100 performs wireless communication with the communication unit 302 of the charger 300, and transmits information obtained by the HMD 100 about the remaining amount of power stored in the batteries 200a, b in use. Furthermore, the communication unit 108 of the HMD 100 transmits a control command such as stopping power transmission from the control unit 101 to the batteries 200a, b in use based on the power usage status of the load within the HMD 100.

In FIG. 6B, the communication unit 302 of the charger 300 performs wireless communication with the communication unit 205c of the battery 200c that is being charged, and information (charged amount) on the power storage state of the battery 200c obtained by the power storage state recognition unit 207 of the battery 200c. is acquired by the charging battery monitoring unit 304 of the charger 300. Furthermore, the communication unit 108 of the HMD 100 performs wireless communication with the communication unit 302 of the charger 300, and the power management unit 106 of the HMD 100 acquires information on the power storage state of the battery 200c that is being charged. In addition, the communication unit 108 of the HMD 100 transmits control commands such as starting/stopping charging to the charger 300 from the control unit 101 based on the remaining amount of power stored in the batteries 200a and 200b in use and the power usage status of the load in the HMD 100. Accordingly, charger 300 controls battery 200c that is being charged.

In this way, the HMD 100 and the charger 300 communicate with each other the remaining amount of power stored in the batteries 200a, b in use and the power storage status information of the battery 200c being charged, and store the information in the respective memory units 105, 303.

FIGS. 7A and 7B show examples of how the battery status is displayed on the display 119 of the HMD 100.

FIG. 7A is an example in which various function menus of the HMD are displayed on the display 119. The user selects a menu 701 related to batteries from this menu palette. To check the battery status, start this menu 701 or leave it always in the active state.

FIG. 7B is an example of displaying the battery status on the display 119. The left display 119a displays a warning urging battery replacement, and the right display 119b displays information on the amount of charge of the batteries in each charging slot. When the remaining battery power decreases, a warning to prompt the battery to be replaced is automatically displayed on the left eye display 119a of the HMD 100, saying "The remaining battery power on the left side is low." At this time, in order to avoid misunderstandings by the user, the information is displayed next to the battery whose remaining battery power is low. When this message appears, the user will be required to replace the left battery.

Further, at this time, the display 119b of the right eye, which is the opposite side, displays the amount of charge of the battery being charged in each slot as a bar. In this display example, it is shown that the charge amount of the battery in slot number 2 is at the maximum, and the number and bar of slot 2 are displayed blinking. At the same time, in the charger 300, the number 312b (number 2) of the battery charging slot 311b blinks in green, and the LED of the battery 200 also blinks in green. When this is displayed, the user can take out the battery being charged in the charging slot 311b and attach it to the HMD.

As described above, according to the configuration of the first embodiment, the user can replenish power by replacing the battery while wearing the HMD 100, and can continue using the HMD without interrupting use. If the battery of a device can be replaced while the device is being used, it is called "hot-swappable." Moreover, since the power transmission from the battery 200 to the HMD 100 and the power transmission from the charger 300 to the battery 200 are wireless power transmission over a short distance, the necessary power can be easily transmitted. Furthermore, since the battery 200 has a structure in which the metal terminals are not exposed to the outside, even when the HMD is worn on the user's head, there is no fear of corrosion of the terminals due to sweat or short circuit between the terminals when replacing the battery. Safe use is possible. For example, even when a user watches a movie for a long time, increasing the number of batteries installed will not affect the fit, and there will be no need to worry about connecting a power supply cable from the terminal of the wearable device to an external power source. Improved usability.

Here, as a modification of the first embodiment, a configuration will be described in which a large amount of data is downloaded from the cloud using the power supply system of the present embodiment.

FIG. 8 is a diagram showing data transmission between the power supply system of this embodiment and the cloud 600. The power supply system includes an HMD 100, a battery 200a that is being used (attached) to the HMD, a charger 300, and a battery 200c that is being charged by the charger.

Data transmission between the HMD 100 and the cloud 600 is carried out in two cases: when downloading image data etc. from the cloud 600 and viewing it on the HMD 100 (symbol 601a), and when transmitting image data acquired by the data input unit 110 (camera 120) of the HMD 100 to the cloud 600. (601b). In either case, since data is directly transmitted between the HMD 100 and the cloud 600, it takes time to transmit large amounts of data such as movies, and there is a concern that the battery capacity may be insufficient. Therefore, in the configuration of this embodiment, data is transmitted via the battery 200 while it is being charged, using the charging time.

The communication unit 302 of the charger 300 downloads data from the cloud 600 and stores it in the memory 206c of the battery 200c that is being charged. When using the charged battery 200c with the HMD 100, data stored in the memory section 206a of the battery 200a in use is read out and viewed (route 602a). Conversely, data generated by the HMD 100 is stored in the memory unit 206 of the battery 200a in use, using the memory unit 105 as a buffer. While this battery is being charged by the charger 300, the stored data is read from the memory unit 206c of the battery 200c and uploaded to the cloud 600 via the communication unit 302 of the charger 300 (path 602b). In this way, by transmitting data to and from the cloud 600 using the memory section of the battery 200 that is being charged, the HMD 100 has the advantage of being able to efficiently transmit large amounts of data.

In the second embodiment, a configuration for replacing the battery of the HMD while using the HMD, that is, a hot swap function will be described. FIG. 9 is a diagram showing control of power transmission between the HMD and the battery. The HMD 100 is equipped with a plurality of batteries 200a and 200b, and a configuration for switching between them is shown.

In the HMD 100, the restriction units 104a and 104b include a backflow prevention diode D, a current detection resistor R, a MOS field effect transistor (MOSFET) M1, and a storage capacitor C in the power lines supplied from the respective batteries 200a and b. . The control unit 101 cuts off the power received from the battery 200 by controlling the MOSFET (M1) to turn on and off.

Furthermore, the power management units 106a and 106b of the HMD 100 include an amplifier and frequency counters 121a and 121b, and detect when the battery 200 is removed from the HMD 100. If the battery 200 is disconnected, the resonance frequency of the wireless power supply in the power receiving units 102a and 102b fluctuates, and this can be detected by monitoring the resonance frequency with the frequency counter 121.

On the other hand, the batteries 200a, 200b include MOS field effect transistors (MOSFETs) M2a, b between the storage battery units 201a, b and the conversion units 202a, b in the power storage units 208a, b. By controlling the MOSFET (M2) by the control units 204a and 204b, the current flowing out from the storage battery units 201a and 201b to the conversion units 202a and 202b is limited. Further, the remaining power storage amount of the battery 200 is determined by measuring the voltage VB between the terminals of the storage battery units 201a and 201b by the power storage state recognition units 207a and 207b.
The following describes the procedure for replacing the battery currently in use in the HMD.

FIG. 10 is a flowchart illustrating a process of removing the battery from the HMD when the remaining power storage capacity of the battery in use becomes insufficient.

The battery 200 in use reads the inter-terminal voltage VB (remaining power storage amount) of the storage battery unit 201 by the power storage state recognition unit 207, and transmits it to the HMD 100 through communication with the HMD 100 (S101). The HMD 100 compares the received voltage VB with a preset first threshold value Vth1 (S102). If the voltage VB is greater than the threshold value Vth1, the battery can be used continuously, and the process returns to S101. However, if the voltage VB becomes smaller than the threshold value Vth1, a warning such as "Battery level is low" is displayed on the display 119 of the HMD 100 (S103). Specifically, as shown in FIG. 7B, the remaining amount of stored power is displayed on the display 119a of the battery that has decreased.

Furthermore, when the battery 200 is used, the battery 200 reads and communicates the terminal voltage VB (S104), and the HMD 100 compares the received voltage VB with a preset second threshold Vth2 (however, Vth2< Vth1) (S105). Since the battery can be used continuously while the voltage VB is greater than the threshold value Vth2, the process returns to S104. However, when the voltage VB becomes smaller than the threshold value Vth2, the battery is removed.

The HMD 100 turns off the MOSFET (M1) of the restriction unit 104 (S106) to prevent reverse current from flowing to the battery 200 side. Furthermore, the controller 200 instructs the battery 200 in use to turn off the MOSFET (M2) to stop the current flowing out from the storage battery unit 201 (S107). At this stage, a warning "Please replace the battery" is displayed on the display 119 of the HMD 100 on the side of the battery that has a reduced amount of remaining power storage (S108).

The user removes the battery 200 from the HMD 100 (S109) and turns off communication between the battery 200 and the HMD 100 (S110).

In addition, instead of the two thresholds Vth1 and Vth2, for safety, a third threshold Vth3 with a margin of about 10% of the remaining power is set, and the user can It is also possible to have the battery replaced while there is still enough battery power remaining.

FIG. 11 is a flowchart showing a process of switching to a standby battery when the remaining power storage capacity of the battery in use becomes insufficient. Here, an example will be described in which the battery 200a on the left side is switched to the battery 200b on the right side.

From S201 to S205, the voltage VB (residual storage amount) between the terminals of the storage battery unit 201a of the battery 200a in use is read and compared with the first threshold Vth1 and the second threshold Vth2 (S201 to S205). This is similar to S101 to S105 in No. 10. When voltage VB becomes smaller than threshold value Vth2 (Yes in S205), switching from battery 200a to battery 200b is performed.

First, the control unit 101 of the HMD 100 turns off the MOSFET (M1a) of the restriction unit 104a on the battery 200a side that is in use, and further turns off the MOSFET (M2a) for the battery 200a that is in use, so that the The current outflow is stopped (S206). Next, the MOSFET (M1b) of the limiting unit 104b on the standby battery 200b side is turned on, and the MOSFET (M2b) of the standby battery 200b is also turned on to start the current outflow from the storage battery unit 201b (S207 ). Thereby, the power receiving system is switched from battery 200a to battery 200b. During this switching, the power of the HMD 100 is provided by the power stored in the capacitor Ca of the restriction unit 104a and the built-in battery of the HMD 100. Therefore, the operation of the HMD 100 is not interrupted due to battery switching.

Thereafter, a warning "Please replace the battery" is displayed on the left display 119a of the HMD 100 (S208). The user removes the battery 200a (S209) and turns off communication between the battery 200a and the HMD 100 (S210).

FIG. 12 is a flowchart showing the process when the battery is removed from the HMD. It describes the process of cutting off the power supply not only when replacing the battery, but also when the battery is disconnected for some reason.

The HMD 100 monitors the resonance frequency FR of the power receiving unit 102 (power receiving coil) using the frequency counter 121 of the power management unit 106 (S301). When the battery 200 in use is removed from the power receiving unit 102 or shifted from a predetermined position, the resonant frequency FR fluctuates. When the frequency counter 121 detects this frequency fluctuation (Yes in S302), the control unit 101 of the HMD 100 turns off the MOSFET (M1) of the restriction unit 104 (S303). Further, the communication unit 108 of the HMD 100 communicates with the battery 200, turns off the MOSFET (M2) of the battery 200, and stops the current flowing out from the storage battery unit 201 (S304). At this stage, a warning "The battery has been removed" is displayed on the display 119 of the HMD 100 on the side where the removed battery is located (S305).

According to the second embodiment, when replacing the battery of the HMD 100, the operation of the HMD 100 is not interrupted and the user can continue to use it, and a hot swap function can be realized.

In Example 3, a structure of a battery 200 suitable for mounting on the HMD 100 or the charger 300 will be described.

FIG. 13 is a diagram showing the operation of attaching the battery 200 to the HMD 100 and charger 300. In the HMD 100, a plurality of magnets 111a, 111b, and 111c are attached to the battery mounting surface of the power receiving unit 102. Although a plurality of magnets are attached here, only one magnet may be used. Further, a ferrite having the same shape is attached to the battery 200. These magnets and ferrites are used to align the power transmitting and receiving coils between the HMD 100 and the battery 200 and to reduce magnetic field leakage. On the other hand, a magnet of the same shape is attached to charger 300 as well, and aligns the power transmitting and receiving coil between charger 300 and battery 200 and reduces magnetic field leakage.

FIG. 14 is a diagram illustrating an example of a power system circuit within battery 200. The battery 200 includes a storage battery section 201, a conversion section 202, and a power transmission/reception section 203. The conversion unit 202 is a bidirectional DC/AC converter, and the coil 203L in the power transmission/reception unit 203 can be used for both power transmission and power reception. The structure of the battery will be explained in detail below.

FIG. 15 is a diagram showing an example of the internal structure of the battery 200, in which (a) is a view seen through the upper lid of the case 214, and (b) is a cross-sectional view taken along the line α-α'. As shown in (b), for example, a storage battery section 201, an electronic board 213, a ferrite plate 211 are mounted in a resin case 214, and ferrite cylinders 212a, 212b, 212c and a coil 203L are mounted on the ferrite plate 211. has been done.

FIG. 16 is a diagram showing a state when the battery 200 is attached to the HMD 100. (a) is a diagram in which a battery is attached to an HMD, and (b) and (c) are β-β' cross-sectional views. The temple portion 114 of the HMD 100 has a shape that covers all the upper and lower surfaces of the battery case 214 in (b), whereas it has a shape that holds a part of the lower part of the case 214 in (c). Even in the case of (c), the battery 200 can be fixed by attracting the ferrites 212, 211 of the battery 200 by the magnet 111 of the HMD 100.

In (b) and (c), a magnet 111 is arranged on a ferrite plate 113 together with a coil 102L in the power receiving unit 102 of the HMD 100. The magnet 111 and the ferrite cylinder 212 of the battery 200 allow the coil 102L of the HMD 100 and the coil 203L of the battery 200 to be aligned. Furthermore, during power transmission, the magnetic field created by the coil 203L passes through the ferrite plates 211, 113, the magnet 111, and the ferrite cylinder 212, so that magnetic field leakage can be reduced.

FIG. 17 is a diagram showing another example of the internal structure of the battery 200, in which (a) is a view seen through the upper lid of the case 214, and (b) is a cross-sectional view taken along the line α-α'. In this example, two sets of coils 203L and two sets of ferrites 211 and 212 are provided on both sides of case 214 of battery 200. When the battery 200 is installed, the coil 203L and ferrites 211 and 212 that are closer to the power receiving unit 102 of the HMD 100 can be used. Therefore, the user can attach the battery 200 without worrying about the side on which the battery 200 is attached.

FIG. 18 is a diagram showing a modification of FIG. 17. In this example, the ends of two sets of coils 203L arranged on both sides inside the case 214 are connected to form one coil. In other words, one coil is bent approximately in the middle and placed on both sides inside the case 214. Also in this case, since the configuration of the battery 200 is symmetrical, it is easy to attach it to the HMD 100 and to install it in the charger 300.

FIG. 19 is a diagram showing the configuration of a charger 400 that charges the battery 200 attached to the HMD 100. The operation of the charger 400 is the same as the charger 300 of the first embodiment, but this figure is for explaining the structure of the charging part, and other parts such as the electronic board inside the charger are omitted. There is. Here, the battery 200 has the structure shown in FIG. 17, and the HMD 100 equipped with the battery 200 is shown installed in the charger 400. The cross-sectional shape of the temple portion 114 of the HMD 100 is as shown in FIG. 16(b). (a) is a view seen from above, (b) is a γ-γ' cross-sectional view, and (c) is a partially enlarged view.

The shape of the charger 400 includes a raised part 401 in the middle and raised charging parts 402a and 402b on both sides of the raised part 401, and the temple part 114 of the HMD 100 is housed between 401 and 402a and 402b. As shown in the enlarged view (c), a power transmission coil 403L for battery charging and a magnet 411 are arranged on a ferrite plate 413 on the inner wall of the charging section 402a.

In the battery 200 attached to the temple portion 114 of the HMD 100, the coil 203L on the left side of the drawing faces the coil 403L of the charger 400. The coil 203L of the battery 200 is used for both power transmission and reception, and the battery 200 can be charged from the coil 403L of the charger 400. Furthermore, due to the attractive force between the magnet 411 of the charger 400 and the ferrite cylinder 212 of the battery 200, the coil 403L of the charger 400 and the coil 203L of the battery 200 are automatically aligned, and sufficient power transmission efficiency is always achieved. can get. Furthermore, during power transmission, the magnetic field created by the coil 403L passes through the ferrite plates 413, 211, the ferrite cylinder 212, and the magnet 411, so that magnetic field leakage can be reduced. For example, simply by placing HMD 100 on charger 400 overnight, battery 200 is charged. Furthermore, with the configuration shown in FIG. 8, data such as necessary movies can be downloaded from the cloud 600.

According to the configuration of the third embodiment, the battery 200 can be easily attached to the HMD 100 and the charger 300, and power transmission efficiency is improved. Moreover, according to the configuration of FIG. 19, it becomes possible to easily charge the battery 200 that is attached to the HMD 100.

In the fourth embodiment, a configuration will be described in which power can be supplied directly to the HMD not only from a battery but also from a charger.

FIG. 20A is a diagram showing the configuration of a power supply system according to the fourth embodiment, in which power can be supplied to the HMD from a battery and a charger. In this example, the HMD 100 includes two batteries 200a,
It shows the flow of power when power is supplied from 200b and also from two chargers 500a and 500b other than the battery. Although two chargers are used here, the number may be arbitrary, and a configuration in which a plurality of chargers are integrated may also be used.

In the batteries 200a and 200b, DC current flows from the storage battery unit 201, is converted to AC current by the conversion unit 202, and power is wirelessly transmitted from the power transmission unit 203 to the HMD 100 at, for example, 150 kHz. This is similar to the operation in FIG. 5A. On the other hand, the chargers 500c and 500d also include a storage battery section 501, a conversion section 502, and a power transmission section 503, and similarly transmit power wirelessly from the power transmission section 503 to the HMD 100.

The HMD 100 has four power receiving units 102a, 102b, 102c, and 102d, and uses the power receiving systems of the power receiving units 102a and 102b from the batteries 200a and 200b, and uses the power receiving system of the power receiving units 102c and 102d from the charger 500. . In each power receiving system, after power is received by the power receiving unit 102, it is converted into a predetermined DC current by the converting unit 103. , is restricted by the restriction unit 104. Further, by enabling the converting unit 103 and the power receiving unit 102 to perform bidirectional power conversion and power transmission, the batteries 200a and 200b can be charged with the power supplied from the chargers 500c and 500d.

FIG. 20B is a diagram showing a specific application example of the power feeding system of FIG. 20A. Here, an example is shown in which a driver uses an HMD. Batteries 200a and 200b are attached to the temple portion of the HMD. On the other hand, power transmission units 503c and 503d of chargers 500c and 500d are arranged, for example, in the headrest of the seat. The power receiving units 102c and 102d of the HMD 100, which receive power from the power transmitting units 503c and 503d, are arranged on the left and right in the temple part near the headrest, for example, in the modern part. When the driver is seated in the seat, the power supply from the charger 500 can be used preferentially and the battery 200 can also be charged. When the driver leaves the seat, the power supply is switched to the battery 200.

According to the configuration of the fourth embodiment, it is possible to use a single battery continuously for a long time, which exceeds the usage time at the battery capacity, while the HMD is attached.

In each of the embodiments described above, the power supply configuration was explained by taking up a glasses-type head mounted display (HMD), but the present invention is not limited to this, and can be similarly applied to other wearable devices. Needless to say.

100: Head mounted display (HMD), 101: Control unit, 102: Power receiving unit, 102L: Coil, 103: Conversion unit, 104: Restriction unit, 105: Memory unit, 106: Power management unit, 107: Sensor unit, 108 : Communication section, 109: Data output section, 110: Data input section, 111: Magnet, 113: Ferrite plate, 114: Temple section, 115: Infrared sensor, 116: Strain sensor, 119: Display, 120: Camera, 121: frequency counter,
200: Battery, 201: Storage battery unit, 202: Conversion unit, 203: Power transmission/reception unit, 203L: Coil, 204: Control unit, 205: Communication unit, 206: Memory unit, 207: Power storage state recognition unit, 208: Power storage unit , 209: display section, 211: ferrite plate, 212: ferrite cylinder, 213: electronic board, 214: case, 215: LED,
300: Charger, 301: Control unit, 302: Communication unit, 303: Memory unit, 304: Charging battery monitoring unit, 305: Display unit, 306: Power supply unit, 307: Storage battery unit, 308: Conversion unit, 309 : Power transmission section, 311: Battery charging slot, 312: Battery slot number,
400: Charger, 401: Raised part, 402: Charging part, 403L: Coil, 411: Magnet, 413: Ferrite plate, 500: Charger, 600: Cloud.

Claims (10)

In wearable devices that users wear on their bodies,
a display for providing information to the user;
A plurality of power receivers are provided with first and second batteries attached to the left and right sides of the display, respectively, as seen from a user wearing the wearable device, and which receive power from the first and second batteries by wireless transmission. Department and
a power management unit that monitors the states of the first and second batteries installed;
a communication unit that performs wireless communication with the first and second batteries installed ;
a plurality of limiting units that limit the power received by the plurality of power receiving units;
a control unit that controls the power receiving unit, the power management unit, the communication unit, the display, and the restriction unit,
The power management unit acquires information on the remaining power storage amount of the first and second batteries installed through the communication unit,
When the control unit determines that the remaining power storage amount of the first battery in use is smaller than a threshold value, the control unit controls a power receiving system from the first battery in use to the second battery in standby. A wearable device characterized in that a warning is displayed on a left side portion of the display to prompt the user to replace the first battery in use. The wearable device according to claim 1,
When the control unit determines that the remaining power storage amount of the second battery in use is smaller than a threshold value, the control unit controls a power receiving system from the second battery in use to the first battery in standby. and displays a warning on the right side of the display to prompt the user to replace the second battery in use.
A wearable device characterized by: In wearable devices that users wear on their bodies,
a display for providing information to the user;
A plurality of power receivers are provided with first and second batteries attached to the left and right sides of the display, respectively, as seen from a user wearing the wearable device, and which receive power from the first and second batteries by wireless transmission. Department and
a power management unit that monitors the states of the first and second batteries installed;
a communication unit that performs wireless communication with the first and second batteries installed;
a plurality of limiting units that limit the power received by the plurality of power receiving units;
a control unit that controls the power receiving unit, the power management unit, the communication unit, the display, and the restriction unit,
The power management unit acquires information on the remaining power storage amount of the first and second batteries installed through the communication unit,
When the control unit determines that the remaining power storage amount of the second battery in use is smaller than a threshold value, the control unit controls a power receiving system from the second battery in use to the first battery in standby. and displays a warning on the right side of the display to prompt the user to replace the second battery in use.
A wearable device characterized by: The wearable device according to any one of claims 1 to 3 ,
The communication department includes:
further performing wireless communication with a third battery or a charger performing a charging operation on the third battery;
Obtaining power storage state information of the third battery or the third battery being charged from the charger,
The control unit includes:
A wearable device, characterized in that information indicating the amount of charge of the third battery is displayed on the display based on the power storage state information. The wearable device according to any one of claims 1 to 3 ,
The communication department includes:
further performing wireless communication with a third battery or a charger performing a charging operation on the third battery;
Obtaining power storage state information of the third battery or the third battery being charged from the charger,
The control unit includes:
The wearable device is characterized in that the display displays information that allows a third battery having the largest amount of charge to be determined based on the power storage state information. In a power supply system consisting of a wearable device, a battery that supplies power to it, and a charger that charges the battery,
The wearable device includes:
a display that provides information to the user;
A plurality of power receivers are provided with first and second batteries attached to the left and right sides of the display, respectively, as seen from a user wearing the wearable device, and which receive power from the first and second batteries by wireless transmission. Department and
a power management unit that monitors the states of the first and second batteries installed and a third battery being charged by the charger;
a communication unit that performs wireless communication with the first and second batteries or the charger that are attached ;
Equipped with
Each of the first to third batteries is
A storage battery unit that stores electricity;
a power transmission/reception unit that transmits power from the storage battery unit to the wearable device by wireless transmission and receives power from the charger to charge the storage battery unit;
a power storage state recognition unit that detects and holds the remaining power storage amount of the storage battery unit or the power storage state information during charging;
Equipped with
The charger includes:
a power transmission unit that transmits power to the third battery that is being charged by wireless transmission;
a charging battery monitoring unit that acquires power storage state information of the third battery that is being charged;
Equipped with
Each of the first to third batteries or the charger is
comprising a communication unit that performs wireless communication with the wearable device,
The wearable device includes:
displaying on the display information on the amount of remaining power storage acquired from the first and second batteries that are installed and information on the power storage state of the third battery that is being charged and acquired from the communication unit;
When it is determined that the remaining power storage amount of the first battery in use is smaller than a threshold value, switching the power receiving system from the first battery in use to the second battery in standby; , a power supply system characterized in that a warning prompting the user to replace the first battery in use is displayed on a left side portion of the display. The power supply system according to claim 6,
When the wearable device determines that the remaining power storage amount of the second battery in use is smaller than a threshold value, the wearable device connects the power receiving system from the second battery in use to the first battery in standby. and displays a warning on the right side of the display to prompt the user to replace the second battery in use.
A power supply system characterized by: In a power supply system consisting of a wearable device, a battery that supplies power to it, and a charger that charges the battery,
The wearable device includes:
a display that provides information to the user;
A plurality of power receivers are provided with first and second batteries mounted on the left and right sides of the display, respectively, as seen from a user wearing the wearable device, and which receive power from the first and second batteries by wireless transmission. Department and
a power management unit that monitors the states of the first and second batteries installed and a third battery being charged by the charger;
a communication unit that performs wireless communication with the first and second batteries or the charger that are attached;
Equipped with
Each of the first to third batteries is
A storage battery unit that stores electricity;
Transmitting power from the storage battery unit to the wearable device by wireless transmission,
a power transmission/reception unit that receives power from the charger to charge the storage battery unit;
a power storage state recognition unit that detects and holds the remaining power storage amount of the storage battery unit or the power storage state information during charging;
Equipped with
The charger is
a power transmission unit that transmits power to the third battery that is being charged by wireless transmission;
a charging battery monitoring unit that acquires power storage state information of the third battery that is being charged;
Equipped with
Each of the first to third batteries or the charger is
comprising a communication unit that performs wireless communication with the wearable device,
The wearable device includes:
displaying on the display information on the amount of remaining power storage acquired from the first and second batteries that are installed and information on the power storage state of the third battery that is being charged and acquired from the communication unit;
When it is determined that the remaining power storage amount of the second battery in use is smaller than a threshold value, switching the power receiving system from the second battery in use to the first battery in standby; , displaying a warning on the right side of the display to prompt the user to replace the second battery in use;
A power supply system characterized by: In the power supply system according to any one of claims 6 to 8 ,
The wearable device includes:
Obtaining power storage state information of the third battery being charged from the communication unit,
Displaying information indicating the amount of charge of the third battery on the display based on the power storage state information,
The third battery or the charger is
A power supply system comprising: a display section that changes a display according to the amount of charge of the third battery. In the power supply system according to any one of claims 6 to 8 ,
The wearable device includes:
Obtaining power storage state information of the third battery being charged from the communication unit,
Displaying information on the display that allows a third battery having the largest amount of charge to be determined based on the storage state information;
The third battery or the charger is
A power supply system comprising: a display section that displays information that allows the third battery having the largest charge amount to be identified.

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