JP2013215036A - Charging guidance system, electronic apparatus, charging guidance program, and recording medium - Google Patents

Abstract

PROBLEM TO BE SOLVED: To guide in non-contact charging so as to be able to easily reach an optimum charging position.SOLUTION: A current detection part 42 detects the value of a current flowing in a power receiving coil 41. A gyro sensor 44 detects a moving direction of a portable terminal 1 moving on a charger 2. An induction control part 43 identifies a moving direction (the same direction or the reverse direction) in which a current is increasing against the detected moving direction on the basis of a change in a current value associated with a movement of the portable terminal 1 and displays it on a display 3.

Description

  The present invention relates to a non-contact charging system in which an electronic device such as a portable terminal equipped with a secondary battery is charged in a non-contact manner electrically from a charger, so that the electronic device can be efficiently charged on the charger. The present invention relates to a charge induction device for inducing equipment.

  As electronic devices such as portable terminals, a model equipped with a secondary battery is widely used so that the portable device can be used easily. For this reason, when the electric power stored in the secondary battery is consumed, it is necessary to charge the secondary battery. In general, charging of the secondary battery is performed by connecting an electronic device including the secondary battery to the charger with a cable, or removing the secondary battery from the electronic device and setting the battery in the charger.

  On the other hand, in recent years, development of contactless charging that does not require connection of a cable or removal of a secondary battery from an electronic device for charging has been advanced. Non-contact charging uses electromagnetic induction and the like, and power is transmitted and received between the power transmission coil of the charger and the power reception coil of the electronic device simply by placing the electronic device on the charger.

  In such non-contact charging, when the central axes of the power transmitting coil and the power receiving coil are shifted, the power transmission efficiency between the two coils is lowered. For this reason, in order to charge efficiently, it is necessary to arrange | position an electronic device to a charger so that the central axes of a power transmission coil and a power reception coil may correspond. However, it is difficult for the user to match the central axes of the power transmission coil and the power reception coil without any index.

  As a technique for solving such inconvenience, for example, in Patent Document 1, the magnitude of the current induced in the power receiving coil is detected, and the magnitude is determined based on the number of lighting of a plurality of LEDs or a single LED. It is disclosed that the time interval between lighting and extinguishing is expressed. Thereby, not only can the magnitude of the induced current be roughly known, but it can also be easily recognized whether it is away from or close to the optimum charging position. Japanese Patent Application Laid-Open No. H10-260260 discloses that a notification is made by voice when the magnitude of the induced current is equal to or greater than a threshold value. Thereby, it can be grasped that satisfactory charging can be performed.

JP 2010-206871 A (published September 16, 2010)

  However, with the LED and voice notifications as described above, it is possible to recognize whether the vehicle is away from or approaching the optimal charging position, but in which direction the electronic device is moved, the optimal charging position is approached. Difficult to grasp. For this reason, it is necessary to perform a trial and error operation in which the user selects an appropriate direction and moves the electronic device to find an optimal moving direction by confirming the notification of the LED or sound. Therefore, there is an inconvenience that it is difficult to reach the optimum charging position in a short time.

  The present invention has been made in view of the above problems, and an object thereof is to provide a charge induction device that can easily reach an optimum charging position in non-contact charging.

  In order to solve the above problems, a charging induction apparatus according to the present invention is a power receiving coil in which a current is induced by electromagnetic induction with a power transmission coil included in a charger, and a charging battery that is charged with a current flowing in the power receiving coil. A charging induction device that induces a current value flowing into the rechargeable battery on the charger to a position where the current value is larger, current detection means for detecting the current value, and the charging Based on the change in the current value accompanying the movement of the electronic device, the movement direction detecting means for detecting the moving direction of the electronic device moving on the vessel, the detected current value is increased. It is characterized by comprising guidance control means for specifying whether to move in the same direction or in the opposite direction with respect to the moving direction and displaying on the display means.

  In the above configuration, when the electronic device is moved from a certain position, the position of the power receiving coil of the electronic device with respect to the power transmission coil of the charger changes, and accordingly, the current value detected by the current detection means also changes. Based on the change in the current value, the guidance control means specifies whether to move in the same direction or the reverse direction with respect to the movement direction detected by the movement direction detection means so that the current value becomes large. Is displayed on the display means. Thus, the direction in which the electronic device should be moved is indicated so that the current value increases.

  Therefore, simply moving the electronic device according to the displayed direction allows the electronic device to be brought closer to a position where the current value becomes larger without requiring a trial and error operation. Therefore, an electronic device can be easily arranged at a position where charging can be performed efficiently.

  In the charging induction device, the induction control unit calculates a change rate of the current value detected when the electronic device moves relative to the current value from the time of detection of the current value, and the change rate is a reference change. Change rate determination means for determining whether the rate of change when reaching the rate is positive or negative, and when it is determined that the rate of change is positive, an indication direction in which the electronic device should move is determined. While specifying the same direction as the moving direction, if it is determined that the rate of change is negative, a pointing direction specifying means for specifying the pointing direction in a direction opposite to the moving direction, and the specified pointing direction It is preferable to have display control means for displaying on the display means.

  In the above configuration, when the change rate of the current value is positive by the indication direction specifying means, the indication direction is specified in the same direction as the movement direction, and when the change rate of the current value is negative, the indication direction is It is specified in the direction opposite to the moving direction. Thereby, if the reference change rate is appropriately set, the electronic device can be brought closer to a position where the current value becomes larger with a desired accuracy.

  In the charging induction device, the change rate determination unit is used to calculate the change rate when the change rate calculated last time is positive and the change rate calculated this time is negative. An intermediate value of the current value detected when the electronic device is moved is calculated, and the detected current value is the intermediate value with respect to the movement of the electronic device in the indicated direction specified in a direction opposite to the moving direction. It is preferable to specify the position when the value is reached as the position where the maximum current value is obtained in the moving direction.

  In the above configuration, when the rate of change remains positive, if the electronic device is moved in the same direction, the electronic device approaches the position where the maximum current value can be obtained. The current value decreases if the value exceeds. Originally, when the rate of change becomes negative, if the electronic device is returned in the reverse direction from that position, it returns to the position before the rate of change of current becomes negative. Therefore, higher charging efficiency can be obtained when the position is set to the place where the charging efficiency is the highest in the reverse movement direction than when the intermediate value is used.

However, there is a possibility that the current value does not return to the previous current value due to a current value detection error or a terminal movement error (an error when moving on a straight line). Therefore, by using an intermediate value, if a current value obtained at a position where the charging efficiency is highest is given a margin (allowable range), it is possible to avoid that the current value does not return. In addition, there is no doubt that the position where the charging efficiency is actually the highest is between the position where the change rate calculated last time is positive and the position where the change rate calculated this time is negative. It is desirable that the high position is an intermediate position between these positions. Therefore, a position where the detected current value coincides with the intermediate value of the current values before and after the change rate decreases is approximately determined as a charging position as a position where the maximum current value in the moving direction of the electronic device can be obtained.

  In the charging induction device, it is preferable that the guidance control unit specifies the indication directions in directions orthogonal to each other and causes the display unit to display the directions.

  In the above configuration, the charging position can be specified two-dimensionally. Therefore, the charging position can be determined more easily and accurately.

  In the charge induction device, it is preferable that the display control unit causes the display unit to display the current value in accordance with the instruction direction.

  It is not possible to grasp that the current value is large only by being guided by the indicated direction, but by displaying the current value, it is possible to visually confirm the change in the current value as the electronic device moves. it can. Therefore, a change in the current value can be detected even with a small movement of the electronic device, and the position of the electronic device can be easily finely adjusted.

  In addition, although the current value notification method using LEDs or sound described in Patent Document 1 can roughly grasp the current value, it can be known only in stages. On the other hand, by displaying the current value, it is possible to know a continuous change in the current value.

  An electronic device according to the present invention includes any one of the charge induction devices described above.

  Thereby, it can guide | invade easily to the position which can charge an electronic device efficiently.

  The charge induction program of the present invention is a program for causing a computer to function as each means in the charge induction device. The recording medium of the present invention is a computer-readable recording medium that records the charging induction program. These charging induction programs and recording media are also included in the technical scope of the present invention.

  The charge induction device according to the present invention, which is configured as described above, has an effect that it can easily reach an optimal charging position in non-contact charging.

It is a longitudinal cross-sectional view which shows schematic structure of the non-contact charging system which concerns on this embodiment. (A) And (b) is a top view which shows the structure of the portable terminal which comprises the said non-contact charge system. It is a block diagram which shows the structure of the electric system of the said non-contact charge system. It is a block diagram which shows the structure of the guidance control part in the said portable terminal. It is a flowchart which shows the procedure which determines the charge position of the said portable terminal by the battery charging part in the said portable terminal. (A) thru | or (c) is a figure which shows the movement process of the said portable terminal until it determines the charging position of the said portable terminal.

  An embodiment according to the present invention will be described below with reference to FIGS.

[Non-contact charging system]
[Configuration of contactless charging system]
FIG. 1 is a longitudinal sectional view showing a schematic configuration of a non-contact charging system 11 according to the present embodiment. FIGS. 2A and 2B are plan views showing the configuration of the mobile terminal 1 constituting the non-contact charging system 11.

  As shown in FIG. 1, the non-contact charging system 11 includes a mobile terminal 1 and a charger 2.

  The portable terminal 1 (electronic device) is necessary for a portable terminal such as a display unit 3, a substrate 10, a power receiving coil 41, a secondary battery 47, and a transmission / reception antenna, although not shown, in a casing 1 a that forms a rectangular parallelepiped. Various parts are built in.

  The display unit 3 (display unit) is provided on the front side (operation surface) of the housing 1a, and includes a flat panel display panel such as a liquid crystal panel and a driving device for driving the display panel. Yes. On the other hand, the power receiving coil 41 and the secondary battery 47 are arranged on the back side of the housing 1a.

  The secondary battery 47 is detachably attached to the mobile terminal 1. The power receiving coil 41 includes a coil 41 a and a magnetic body 41 b disposed at the center of the coil 41 a and is mounted on the substrate 10. Various components (excluding the secondary battery 47) constituting the battery charging unit 4 (see FIG. 3) described later are mounted on the mounting surface of the substrate 10 opposite to the mounting surface of the power receiving coil 41.

  On the other hand, the charger 2 incorporates a substrate 20 and a power transmission coil 25 and parts constituting various circuits (not shown) for driving the power transmission coil 25, which will be described later, in a rectangular parallelepiped casing 1a. Yes. These components are mounted on the substrate 20. The charger 2 has a flat upper end surface so that the portable terminal 1 can be placed thereon.

  In the non-contact charging system 11, the power transmission coil 25 and the power receiving coil 41 are arranged to face each other with the mobile terminal 1 placed on the charger 2, so that A transformer is formed. In such a configuration, when an alternating current flows through the power transmission coil 25 due to electromagnetic induction between the power transmission coil 25 and the power reception coil 41, an induced voltage is generated in the power reception coil 41 and a current flows. In this way, the power of the charger 2 is transmitted to the portable terminal 1 in a contactless manner.

  When the power transmission coil 25 and the power reception coil 41 are arranged so that their central axes coincide with each other, the coupling efficiency is highest. Therefore, in this state, since the current flowing through the power receiving coil 41 is maximized, the secondary battery 47 can be charged with the highest efficiency.

  Various screens for operating the portable terminal 1 are displayed on the display unit 3. At the time of charging, as shown in FIG. 2A, a direction instruction screen 101 is displayed, or FIG. As shown in b), a charging position determination screen 201 is displayed.

The direction instruction screen 101 includes a direction instruction mark 102 and a current value display area 103. The direction indication mark 102 is a symbol indicating a direction in which the current value becomes larger when the mobile terminal 1 moves on the charger 2, and is represented by an arrow, for example. The current value display area 103 is an area provided for displaying the value of the current flowing through the power receiving coil 41 that is measured while the mobile terminal 1 is moved.

  A direction instruction screen 101 that indicates a moving direction as one direction includes a direction instruction mark 102 that faces the direction. On the other hand, the direction indication screen 101 that does not indicate the movement direction as one direction includes a direction indication mark 102 that faces in both directions. The direction instruction screen 101 is used, for example, to prompt the user to move the mobile terminal 1 when determining the charging position in a direction orthogonal to the horizontal charging position after the horizontal charging position is determined.

  The charging position determination screen 201 includes a charging position determination mark 202 and a current value display area 203. The charging position determination mark 202 is a symbol indicating that the mobile terminal 1 has reached a position where the maximum current value can be obtained on the charger 2, and is represented by a circle, for example. The current value display area 203 is an area provided for displaying the value of the current flowing through the power receiving coil 41 measured at the position where the charging efficiency is highest.

[Electric system configuration of non-contact charging system]
FIG. 3 is a block diagram showing the configuration of the electrical system of the contactless charging system.

<Charger configuration>
As shown in FIG. 3, the charger 2 includes a rectifying / smoothing circuit 21, a voltage conversion circuit 22, a switching circuit 23, a control circuit 24, and a power transmission coil 25 in order to supply power for charging to the mobile terminal 1. Yes.

  The rectifying / smoothing circuit 21 is a circuit that rectifies and smoothes the alternating voltage and alternating current from the commercial power supply 12 into direct current. The voltage conversion circuit 22 is a circuit that converts (boosts) the DC voltage from the rectifying and smoothing circuit 21 to a desired voltage. The switching circuit 23 is a circuit that switches the DC voltage from the voltage conversion circuit 22 at a predetermined frequency. The control circuit 24 is a circuit for controlling the switching operation of the switching circuit 23.

<Configuration of battery charger>
As illustrated in FIG. 3, the mobile terminal 1 includes a battery charging unit 4 (charging induction device) for charging a secondary battery 47 (charging battery). The battery charging unit 4 includes a power receiving coil 41, a current detection unit 42, an induction control unit 43, a gyro sensor 44, a rectifier circuit 45, a charging current adjustment circuit 46, and a secondary battery 47.

  The current detection unit 42 (current detection unit) is a sensor or a circuit that detects a current flowing through the power receiving coil 41. The gyro sensor 44 (movement direction detection means) is a sensor that detects angular velocity, and is used to detect the movement direction of the mobile terminal 1 because it detects the direction of movement.

  The induction control unit 43 performs control for guiding the mobile terminal 1 placed on the charger 2 to a position where the secondary battery 47 can be charged with the highest efficiency as described above. For this reason, the guidance control unit 43 guides to the position where the current value becomes maximum based on the moving direction of the mobile terminal 1 detected by the gyro sensor 44 and the current value detected by the current detection unit 42. The direction in which the mobile terminal 1 should be moved is specified and displayed on the display unit 3. The guidance control unit 43 will be described in detail later.

The rectifier circuit 45 is a circuit that rectifies alternating induced voltage and induced current generated in the power receiving coil 41. The charging current adjustment circuit 46 is a circuit that adjusts the rectified current output from the rectifier circuit 45 to a direct current suitable for the secondary battery 47 in accordance with the current value detected by the current detector 42.

<Configuration of guidance control unit>
FIG. 4 is a block diagram illustrating a configuration of the guidance control unit 43 in the mobile terminal 1.

  As shown in FIG. 4, the guidance control unit 43 (guidance control means) includes a control unit 431, a RAM 432, a ROM 433, a current comparison calculation unit 434, an instruction direction specifying unit 435, a charging position determination unit 436, and a display control unit 437. It is out.

<Control unit configuration>
The control unit 431 controls each unit of the guidance control unit 43 as follows in order to realize the above-described guidance control function. The control unit 431 is a block of control functions that are realized by the microprocessor executing a predetermined control program.
(1) Reading / Writing of Detected Current The control unit 431 writes the current value detected by the current detection unit 42 in the RAM 432 at a predetermined interval and stores it in the RAM 432 in response to a request from the indication direction specifying unit 435. Further, the control unit 431 reads out a current value from the RAM 432 in response to a request from the current comparison calculation unit 434.
(2) Reading / Writing of Movement Direction The control unit 431 writes the movement direction of the mobile terminal 1 detected by the gyro sensor 44 in the RAM 432. As a result, the latest movement direction of the mobile terminal 1 is updated in the RAM 432. In addition, the control unit 431 reads the movement direction from the RAM 432 in response to a request from the instruction direction specifying unit 435.
(3) Reading Display Screen Data The control unit 431 reads the display screen data stored in the ROM 433 in response to a request from the display control unit 437.
(4) Display of Current Value The control unit 431 instructs the display control unit 437 to display the current value detected by the current detection unit 42 on the direction instruction screen 101 and the charging position determination screen 201.

<< Configuration of RAM and ROM >>
A RAM (Random Access Memory) 432 is a memory for storing the current value and the moving direction. The RAM 432 is also used as a work area for temporarily storing data when the control unit 431, the current comparison calculation unit 434, the indication direction specifying unit 435, and the display control unit 437 perform respective processes.

  A ROM (Read Only Memory) 433 is a memory for storing the display screen data. As the display screen data, various screen data for operating the portable terminal 1 and data of the direction instruction screen 101 and the charging position determination screen 201 described above are prepared.

<Configuration of current comparison calculation unit>
The current comparison calculation unit 434 (change rate determination means) is a current value (detected current value) detected by the current detection unit 42 when the mobile terminal 1 is moved with respect to a current value (stored current value Im) stored in the RAM 432 in advance. A current change rate Ri that is a change rate of Id) is calculated. The current comparison calculation unit 434 calculates the current change rate Ri based on the following equation at a predetermined time interval. As a result, it is determined how much the current value has changed from the time of detection of the stored current value to an arbitrary time when the mobile terminal 1 is moved.

Ri = (Id−Im) / Im
The current comparison calculation unit 434 determines whether or not the current change rate Ri has reached a predetermined reference change rate (for example, 5%) by comparing the current change rate Ri with the reference change rate. The reference change rate is stored in the ROM 433, for example.

  When determining that the current change rate Ri has reached the reference change rate, the current comparison calculation unit 434 determines whether or not the current change rate Ri is a positive value. When the current change rate Ri is a positive value, since Id> Im, the current change rate Ri is improved. On the other hand, when the current change rate Ri is a negative value, since Id <Im, the current change rate Ri is reduced. Further, the current comparison calculation unit 434 requests the control unit 431 to store the detected current value Id used for the above determination in the RAM 432.

  When the current comparison calculation unit 434 determines that the current change rate Ri calculated last time is a positive value and then determines that the current change rate Ri calculated this time is negative, the current comparison calculation unit 434 uses each determination. An intermediate value of the stored storage current value Im is calculated, and the detected current value Id detected thereafter is compared with the intermediate value. Further, when the current comparison calculation unit 434 determines that the detected current value Id and the intermediate value match as a result of the comparison, the current comparison calculation unit 434 identifies the position of the portable terminal 1 at that time as the charging position, and this is indicated by the display control unit. 437 is notified. In the above processing, the current comparison calculation unit 434 requests the control unit 431 to read the storage current value Im used to calculate the intermediate value, and also determines the intermediate value when the coincidence between the detected current value Id and the intermediate value is determined. Is requested to the control unit 431 to be stored in the RAM 432.

  The position where the detected current value Id matches the intermediate value is determined as the charging position for the following reason.

Assume that the stored current value Im stored at the previous detection is detected at the position Pm, and the detected current value Id detected at the current detection is detected at the position Pd.
While the current change rate Ri continues to improve, if the mobile terminal 1 is moved in the same direction, the mobile terminal 1 approaches the position where the maximum current value can be obtained, and the mobile terminal 1 moves to that position. If too much, the current value decreases. Originally, when the detected current value Id detected this time is 5% lower than the previously detected storage current value Im, if the portable terminal 1 is returned in the reverse direction from the position Pd which has been reduced by 5%, it will be reduced by 5%. Return to position Pm. Therefore, a higher charging efficiency can be obtained when the position Pm is the place where the charging efficiency is the highest in the reverse movement direction than when the intermediate value is used.

  However, there is a possibility that the detected current value Id does not return to the stored current value Im before the detection current value Id is reduced by 5% due to a current value detection error or a terminal movement error (an error when moving on a straight line). Therefore, by using an intermediate value, if a margin (allowable range) is given to the current value obtained at the position where the charging efficiency is the highest, the detection current value Id is improved by 2.5% from the reduced state. It is possible to avoid not returning to the value. In addition, there is no doubt that the position where the charging efficiency is actually the highest is between the position Pd and the position Pm. Therefore, the position where the charging efficiency is the highest is preferably an intermediate position between the position Pd and the position Pm. .

  Accordingly, the position where the detected current value Id reaches the intermediate value of the stored current value Im before and after the current change rate Ri decreases is approximately determined as the charging position.

《Configuration of pointing direction identification unit》
When the current comparison calculation unit 434 determines that the current change rate Ri is a positive value, the instruction direction specifying unit 435 (instruction direction specifying unit) is the same as the moving direction of the mobile terminal 1 when the determination is made. The direction in which the portable terminal 1 should move is specified in the direction. In addition, when it is determined that the current change rate Ri is a negative value, the instruction direction specifying unit 435 specifies the instruction direction in a direction opposite to the moving direction of the mobile terminal 1 when the determination is made. For this reason, the designated direction specifying unit 435 requests the control unit 431 to read out the moving direction from the RAM 432, specifies the same direction as or the opposite direction to the read moving direction as the designated direction, and performs display control of this direction. Notification to the unit 437.

<Configuration of charging position determination unit>
The charging position determination unit 436 determines whether or not the charging position is specified also in the direction orthogonal to the direction in which the charging position is specified. If the charging position determination unit 436 determines that the charging position in the orthogonal direction is to be specified, the charging control unit 436 causes the display control unit 437 to display the direction instruction screen 101 indicating the moving direction in the orthogonal direction (two directions instead of one direction). Give instructions. If charging position determination unit 436 determines that the charging position in the orthogonal direction is specified, it determines the charging position and gives an instruction to display control unit 437 to display charging position determination screen 201.

<Configuration of display control unit>
The display control unit 437 (display control unit) gives an instruction to the display unit 3 to display the direction instruction screen 101 indicating the instruction direction specified by the instruction direction specifying unit 435. Specifically, the display control unit 437 requests the control unit 431 to read the display screen data of the direction instruction screen 101 indicating the specified instruction direction, and gives the acquired display screen data to the display unit 3.

  When the display control unit 437 receives an instruction to display the direction instruction screen 101 indicating the direction orthogonal to the direction in which the charging position is determined from the charging position determination unit 436, the display control unit 431 reads the display screen data of the direction instruction screen 101. And the obtained display screen data is given to the display unit 3. Further, the display control unit 437 gives an instruction to the display unit 3 to display the charging position determination screen 201 when the charging position is determined by the charging position determination unit 436. Specifically, the display control unit 437 requests the control unit 431 to read the display screen data of the charging position determination screen 201 and gives the acquired display screen data to the display unit 3.

  The display control unit 437 receives an instruction to display the current value from the control unit 431, and displays the current value in the current value display areas 103 and 203 of the direction instruction screen 101 and the charging position determination screen 201, respectively. Instruct part 3. Specifically, the display control unit 437 gives the current value acquired via the control unit 431 to the display unit 3 in a state of being incorporated in the display screen data.

<Realization form of guidance control unit>
Each block of the control unit 431, the current comparison calculation unit 434, the instruction direction specifying unit 435, and the display control unit 437 in the induction control unit 43 is realized by software (charging induction program) using a CPU as follows. That is, this charging induction program causes the computer to function as the induction control unit 43.

  Or each said block may be comprised by a hardware logic, and may be implement | achieved by the process by the program using DSP (Digital Signal Processor).

  The program code (execution format program, intermediate code program, source program) of the above software may be recorded on a recording medium recorded so as to be readable by a computer. The object of the present invention can also be achieved by supplying the recording medium to the portable terminal 1 and reading and executing the program code recorded on the recording medium by the CPU.

Examples of the recording medium include magnetic tapes such as magnetic tapes and cassette tapes, magnetic disks such as floppy (registered trademark) disks / hard disks, and optical disks such as CD-ROM / MO / MD / BD / DVD / CD-R. Can be used. In addition, a card system such as an IC card (including a memory card) / optical card or a semiconductor memory system such as a mask ROM / EPROM / EEPROM / flash ROM can be used as the recording medium.

The mobile terminal 1 may be configured to be connectable to a communication network, and the program code may be supplied via the communication network. The communication network is not particularly limited. For example, the Internet, intranet, extranet, LAN, ISDN, VAN, CATV communication network, virtual private network, telephone line network, mobile communication network, satellite communication. A net or the like is available. Moreover, the transmission medium which comprises a communication network is not specifically limited. For example, as the above transmission medium, wired cables such as IEEE 1394, USB, power line carrier, cable TV line, telephone line, ADSL line and the like can be used. Alternatively, as the transmission medium, infrared rays such as IrDA and remote control, Bluetooth (registered trademark), 802.11 wireless, HDR, mobile phone network, satellite line, terrestrial digital network, and the like can be used.

  The present invention can also be realized in the form of a computer data signal embedded in a carrier wave in which the program code is embodied by electronic transmission.

[Induction to charging position in non-contact charging system]
Here, in the non-contact charging system 11, an induction operation up to the charging position of the mobile terminal 1 will be described.

[Processing procedure during guidance]
FIG. 5 is a flowchart illustrating a procedure for determining the charging position of the mobile terminal 1 by the battery charging unit 4.

  First, when the mobile terminal 1 is placed on the charger 2, the power transmission coil 25 of the charger 2 and the power reception coil 41 of the mobile terminal 1 are electromagnetically coupled, and an induced current flows through the power reception coil 41. In this state, since the portable terminal 1 can be guided, the process starts as shown in FIG.

  First, the current value of the induced current measured (detected) by the current detection unit 42 is measured, and the current value is stored in the RAM 432 (step S1). Based on the movement direction detected by the gyro sensor 44, the control unit 431 detects the movement of the mobile terminal 1 by a user operation (step S2). The current detector 42 continues to measure the current value while the mobile terminal 1 is moving (step S3). The control unit 431 gives the measured current value to the current comparison calculation unit 434.

  The current comparison calculation unit 434 calculates a current change rate Ri based on the current value stored in step S1 and the current value given when the mobile terminal 1 is moved (step S4), and the current change rate Ri is calculated. It is determined whether or not the reference change rate has been reached (step S5). If the current change rate Ri does not reach the reference change rate, the process returns to step S3. When the current comparison calculation unit 434 determines that the current change rate Ri has reached the reference change rate, the current comparison calculation unit 434 determines whether the current change rate Ri is further improved (positive) or not (decreased). (Step S6).

  When it is determined in step S6 that the current change rate Ri is improved, the control unit 431 stores the current value (detected current value Id) at that time in the RAM 432 (step S7). In addition, when the instruction direction specifying unit 435 receives the above determination and instructs the display unit 3 to display the instruction direction that is the same as the moving direction of the mobile terminal 1, the display unit 3 indicates the instruction direction. The direction instruction screen 101 is displayed (step S8).

On the other hand, when it is determined in step S6 that the current change rate Ri is decreasing, the control unit 431 stores the current value (detected current value Id) at that time in the RAM 432 (step S9). In addition, when the instruction direction specifying unit 435 receives the above determination and instructs the display unit 3 to display the instruction direction opposite to the moving direction of the mobile terminal 1, the display unit 3 indicates the instruction direction. The direction instruction screen 101 is displayed (step S10).

  When the user moves the portable terminal 1 in the direction displayed as described above, the control unit 431 detects the movement of the portable terminal 1 based on the movement direction detected by the gyro sensor 44 (step S11). The current detection unit 42 continues to measure the current value while the mobile terminal 1 is moving (step S12). The control unit 431 gives the measured current value to the current comparison calculation unit 434.

  The current comparison calculation unit 434 calculates the current change rate Ri based on the current value stored in step S7 or step S9 and the current value given when the mobile terminal 1 is moved (step S13), and this current change. It is determined whether or not the rate Ri has reached the reference change rate (step S14). If the current change rate Ri has reached the reference change rate, the process returns to step S12. Further, when the current comparison calculation unit 434 determines that the current change rate Ri has not reached the reference change rate, the current comparison rate Ri further determines whether the current change rate Ri is improved (positive) or not (decreased). Determination is made (step S15).

  When it is determined in step S15 that the current change rate Ri is improved, the control unit 431 stores the current value (detected current value Id) at that time in the RAM 432 (step S16). In addition, when the instruction direction specifying unit 435 receives the above determination and instructs the display unit 3 to display the instruction direction that is the same as the moving direction of the mobile terminal 1, the display unit 3 indicates the instruction direction. The direction instruction screen 101 is displayed (step S17). Thereafter, the process is returned to step S12, and the processes of steps S12 to S15 are repeated until it is determined that the current change rate Ri is decreasing.

  If it is determined in step S15 that the current change rate Ri is decreasing, the control unit 431 stores the current value (detected current value Id) at that time in the RAM 432 (step S18). In addition, when the instruction direction specifying unit 435 receives the above determination and instructs the display unit 3 to display the instruction direction opposite to the moving direction of the mobile terminal 1, the display unit 3 indicates the instruction direction. The direction instruction screen 101 is displayed (step S19).

  When the user moves the portable terminal 1 in the direction displayed as described above, the control unit 431 detects the movement of the portable terminal 1 based on the movement direction detected by the gyro sensor 44 (step S20). The current detection unit 42 continues to measure the current value while the mobile terminal 1 is moving (step S21). The control unit 431 gives the measured current value to the current comparison calculation unit 434.

  The current comparison calculation unit 434 calculates an intermediate value between the current value stored in step S18 and the current value stored last time, and determines the intermediate value of the changing current value given when the mobile terminal 1 is moved. The values are sequentially compared (step S22). In addition, the current comparison calculation unit 434 determines whether or not the current value has reached an intermediate value during the comparison process (step S23). If the current value does not reach the intermediate value, the process returns to step S21, and the processes of steps 21 to 23 are repeated until the current value reaches the intermediate value.

  When determining that the current value has reached the intermediate value, the current comparison calculation unit 434 specifies the position of the mobile terminal 1 at that time as the charging position (step S24). The control unit 431 stores the current value (detected current value Id) at that time in the RAM 432 (step S25).

  The charging position determination unit 436 determines whether or not the charging position is specified in the direction orthogonal to the direction in which the charging position is determined (step S26). Here, if the charging position in the orthogonal direction is not specified, the charging position determination unit 436 instructs the display control unit 437 to display the direction instruction screen 101 indicating the orthogonal direction (two directions instead of one direction). . Then, the display part 3 receives the instruction | indication of the display control part 437, and displays the direction instruction | indication screen 101 which shows an orthogonal direction (step S27).

  After step S27, the process returns to step S2, and the processes of steps S2 to S26 are performed. As a result, when the charging position determination unit 436 determines in step S26 that the charging position in the orthogonal direction has been specified, the charging position is determined and the display control unit 437 displays the charging position determination screen 201 for the charging position. To instruct. Thereby, the display part 3 receives the instruction | indication of the display control part 437, and displays the charge position determination screen 201 (step S28). In this way, the charging position determination process is completed.

  In the process of calculating the current change rate Ri in step S4 performed in the orthogonal direction, the current value stored in step S25 is used instead of the current value stored in step S1.

[Specific examples of guidance]
Here, a specific example of guidance of the mobile terminal 1 will be described with reference to the flowchart of FIG.

  FIGS. 6A to 6C are diagrams illustrating the movement process of the mobile terminal 1 until the charging position of the mobile terminal 1 is determined.

  As shown in FIG. 6A, in the state A in which the mobile terminal 1 is placed at the position P0 on the charger 2, the mobile terminal 1 is not moved, so that nothing is displayed on the display unit 3. Absent. In the state A, the current value measured by the current detection unit 42 is stored in the RAM 432 by the process of step S1.

  It is assumed that the mobile terminal 1 is moved in the direction X1 from the state A to the state B. In the state C in which the portable terminal 1 is moved to P1, when the measured current value increases and the current change rate Ri is improved, the display unit 3 displays the right side by the processing of steps S2 to S8. A direction indication screen 101 including a direction indication mark 102 facing toward is displayed. In this state, the measured current value is displayed in the current value display area 103 every moment on the direction indication screen 101. Thereby, the change in the current value can be confirmed as the mobile terminal 1 moves.

  According to the direction indication mark 102, the portable terminal 1 is further moved from the state C in the direction X1, and the movement in the same direction is continued while the right direction indication mark 102 is displayed. As a result, in the state D where the portable terminal 1 has reached the position P2, if the position (horizontal charging position) where the maximum current value is obtained in the horizontal direction is passed, the current value decreases. In this case, the direction instruction screen 101 including the direction instruction mark 102 facing leftward is displayed on the display unit 3 by the processing of steps S11 to S19 (state E).

When the portable terminal 1 is moved in the opposite direction X2 from the state E according to the direction indication mark 102, the processing of steps S20 to S23 is performed, and it is determined that the current value has reached the intermediate value at the position P3. (State F). In the state F, since it is closest to the position where the maximum current value is obtained in the horizontal direction, that position is specified as the charging position. Accordingly, the direction indication screen 101 including the direction indication mark 102 oriented in the vertical bidirectional direction is displayed by the processing in steps S24 to S27 so as to perform guidance to the charging position in the vertical direction orthogonal to the horizontal direction. (State G).

  In the state G, since the position where the maximum current value is obtained in the vertical direction is not known, the mobile terminal 1 may be moved in either the vertical direction Y1 or the direction Y2. Here, as shown in FIG. 6B, for example, when the mobile terminal 1 is moved in the direction Y1, the processes in steps S2 to S26 are performed also in the vertical direction. Therefore, the portable terminal 1 is moved in the direction Y1 or the direction Y2 according to the display of the direction instruction screen 101 in the same procedure as in the state C to the state F or the state H to the state K. As a result, when the charging position is specified at the position Pc also in the vertical direction, the charging position determination screen 201 including the charging position determination mark 202 is displayed as shown in FIG. The

  On the other hand, in the state H in which the portable terminal 1 is moved to P1, when the measured current value is reduced and the current change rate Ri is reduced, the processes of steps S2 to S6, S9, and S10 are performed. . As a result, the direction indication screen 101 including the direction indication mark 102 facing left is displayed on the display unit 3.

  According to this direction indication mark 102, the portable terminal 1 is further moved from the state H in the direction X2, and the movement in the same direction is continued while the left direction indication mark 102 is displayed. As a result, in the state I where the mobile terminal 1 has reached the position P4, assuming that the position (horizontal charging position) where the maximum current value is obtained in the horizontal direction is passed, the current value decreases. In this case, the direction indication screen 101 including the direction indication mark 102 facing right is displayed on the display unit 3 by the processing of steps S11 to S19 (state J).

  When the portable terminal 1 is moved from the state J to the opposite direction X1 according to the direction indication mark 102, the processing of steps S20 to S23 is performed, and it is determined that the current value has reached the intermediate value at the position P5. (State K). In the state K, since it is closest to the position where the maximum current value is obtained in the horizontal direction, that position is determined as the charging position. Accordingly, the direction indication screen 101 including the direction indication mark 102 oriented in the vertical direction is displayed by the processing in steps S24 to S27 so as to perform guidance to the charging position in the vertical direction orthogonal to the horizontal direction. (State L).

  In the state L, since the position where the maximum current value is obtained in the vertical direction is not known, the portable terminal 1 may be moved in either the vertical direction Y1 or the direction Y2, although not shown. As a result, when the charging position is specified also in the vertical direction, the charging position determination screen 201 including the charging position determination mark 202 is displayed by the process of step S28.

  In the above example, after the charging position in the horizontal direction is specified, the charging position in the direction orthogonal to the horizontal direction is specified, but the reverse is also possible.

  Further, the direction for specifying the charging position may be not only the horizontal direction and the vertical direction but also an oblique direction. In this case, first, when the mobile terminal 1 is moved in the right oblique direction or the left oblique direction, a direction indication screen 101 including a direction indication mark 102 facing in the oblique direction is displayed. Moreover, after specifying a charging position, the portable terminal 1 is moved to the diagonal direction orthogonal to it, and a charging position is specified. The direction of the direction indication mark 102 differs depending on whether the direction in which the mobile terminal 1 is first moved is the right diagonal direction or the left diagonal direction. For this reason, the control unit 431 may determine which direction instruction screen 101 including the direction instruction mark 102 to display based on the moving direction of the mobile terminal 1 detected by the gyro sensor 44. Good.

[Effects of battery charger]
As described above, the mobile terminal 1 has the battery charging unit 4, and thus the position where the current value increases is based on the stored current value and the measured current value, with the induction control unit 43 as the center. An indication direction in which the mobile terminal 1 should be moved is displayed on the display unit 3 so as to guide the user. Thus, the user can easily move the mobile terminal 1 in accordance with the indicated direction, and can easily set the charging position of the mobile terminal 1 to a position where the maximum current value can be obtained without requiring trial and error operations. You can get closer. Therefore, the non-contact efficiency of the portable terminal 1 can be performed efficiently.

  In addition, since the current measured by the current detection unit 42 is displayed on the direction instruction screen 101 and the charging position determination screen 201, the current value that changes as the mobile terminal 1 moves can be easily confirmed. . Therefore, a change in the current value can be detected even with a small movement of the mobile terminal 1, and the position of the mobile terminal 1 can be easily finely adjusted.

  In the above example, the charging position is also specified in the direction orthogonal to the direction in which the charging position is first specified. However, the present invention is not limited to this, and only the direction in which the charging position is first specified may be guided. In this case, for the direction orthogonal to the direction in which the charging position is first specified, the charging position may be specified depending on the displayed current value. Even if it does in this way, compared with the guidance method indicated in patent documents 1, guidance of portable terminal 1 can be made easy.

  However, the charging position can be specified two-dimensionally by specifying and displaying the indication directions in directions orthogonal to each other like the horizontal direction and the vertical direction described above. Therefore, it goes without saying that the charging position can be determined more easily and accurately.

[Additional Notes]
In this embodiment, the example in which the electronic device to be charged is the mobile terminal 1 has been described. However, as the electronic device, a device that has a secondary battery and is charged from a charger in a non-contact manner using electromagnetic coupling. If it is, it will not be limited to the portable terminal 1. For example, examples of the electronic device include devices such as a portable music player, a portable radio, a portable television, a portable navigation, and an electric shaver.

  Further, in the present embodiment, the current value is displayed, but other than this, the remaining time until full charge and the charging speed may be displayed.

  Further, in the present embodiment, the example in which the moving direction and the current value are displayed on the display unit 3 of the mobile terminal 1 has been described, but the display mode of the moving direction and the current value is not limited to this. For example, when using an electronic device that does not have a means for displaying the moving direction and the current value, the charger is provided with a means for displaying and a control means having a function equivalent to that of the above-described guidance control unit 43. Just keep it. Further, if the current value detected by the current detection unit 42 and the movement direction detected by the gyro sensor 44 are transmitted from the electronic device to the charger by wireless communication, the charger uses the received data to move the movement direction. And the current value can be displayed.

  In this embodiment, the example in which the reference change rate compared with the current change rate Ri is 5% has been described. However, the reference change rate is not limited to this, and may be larger or smaller than 5%. . Thereby, the portable terminal 1 can be guided to the charging position with desired accuracy.

  However, when the reference change rate is smaller than the current value detection error and the terminal movement error (error from the case of moving on a straight line), even if the current change rate Ri with respect to the moving direction is positive, the error causes the current change rate. Ri may be determined to be negative. On the other hand, even if the current change rate Ri with respect to the moving direction is negative, the current change rate Ri may be determined to be positive due to the error. Therefore, in order to prevent such erroneous determination, it is preferable that the reference change rate is not too small.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope shown in the claims. That is, embodiments obtained by combining technical means appropriately modified within the scope of the claims are also included in the technical scope of the present invention.

  The charging induction device according to the present invention is easy to move to a position where the maximum current value can be obtained by indicating the moving direction of the electronic device to be charged in the direction in which the current flowing through the power receiving coil of the electronic device increases. Therefore, it can be suitably used for a non-contact charging system.

1 Mobile terminal (electronic equipment)
2 Charger 3 Display section (display means)
4 Battery charger (charge induction device)
DESCRIPTION OF SYMBOLS 11 Non-contact charge system 25 Power transmission coil 41 Power reception coil 42 Current detection part (current detection means)
43 Guidance control unit (guidance control means)
44 Gyro sensor (moving direction detection means)
47 Secondary battery (rechargeable battery)
101 Direction indication screen 102 Direction indication mark 103 Current value display area 201 Charging position determination screen 202 Charging position determination mark 203 Current value display area 431 Control unit 432 RAM
433 ROM
434 Current comparison calculation unit (change rate determination means)
435 Pointing direction specifying unit (pointing direction specifying means)
436 Charging position determination unit 437 Display control unit (display control means)

Claims (8)

With respect to an electronic device having a power receiving coil in which a current is induced by electromagnetic induction with a power transmission coil included in the charger and a charging battery charged with a current flowing in the power receiving coil, the charging battery on the charger A charge induction device that induces a position where the current value flowing into the battery becomes larger,
Current detection means for detecting the current value;
A moving direction detecting means for detecting a moving direction of the electronic device moving on the charger;
Based on the change of the current value accompanying the movement of the electronic device, the display unit specifies whether to move in the same direction or the reverse direction with respect to the detected moving direction so that the current value becomes large A charging induction device comprising: an induction control means for displaying on the battery. The guidance control means includes
The rate of change of the current value detected when the electronic device with respect to the current value has moved from the time of detection of the current value is calculated, and the rate of change when the rate of change reaches a reference rate of change is positive or Change rate determination means for determining which is negative,
When it is determined that the rate of change is positive, the indication direction in which the electronic device should move is specified in the same direction as the direction of movement, while when the rate of change is determined to be negative, the indication direction Indicating direction specifying means for specifying a direction opposite to the moving direction;
The charge induction device according to claim 1, further comprising display control means for displaying the specified indication direction on the display means.   The change rate determination means detects when the electronic device used to calculate the change rate is moved when the change rate calculated last time is positive and the change rate calculated this time is negative. When the detected current value reaches the intermediate value with respect to the movement of the electronic device in the indicated direction specified in the direction opposite to the moving direction, the intermediate value of the measured current value is calculated. The charging induction device according to claim 2, wherein the position is specified as a position where a maximum current value is obtained in the moving direction.   4. The charging induction device according to claim 2, wherein the guidance control unit specifies the indication directions in directions orthogonal to each other and displays the directions on the display unit. 5.   5. The charging induction device according to claim 2, wherein the display control unit causes the display unit to display the current value in accordance with the instruction direction. 6.   An electronic apparatus comprising the charge induction device according to any one of claims 1 to 5.   A charge induction program for causing a computer to function as the induction control means in the charge induction device according to any one of claims 1 to 5.   The computer-readable recording medium which recorded the charge induction program of Claim 7.

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