JP2014023296A - Power transmission coil - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a power transmission coil from which foreign materials can be removed with a simple construction.SOLUTION: A power transmission coil 11 has a planar coil 13, a foreign material removing body 15 which is provided to the upper surface side of the planar coil 13 so as to be movable along the upper surface of the planar coil 13, a magnet 17 which is secured so as to pass the projection plane of the planar coil 13 on the foreign material removing body 15 when the foreign material removing body 15 is moved, and a power control circuit 19 which is electrically connected to the planar coil 13. The power control circuit 19 controls current to be supplied to the planar coil 13 so that the magnet 17 moves along the upper surface of the planar coil 13 at least before power transmission by the planar coil 13 is started.

Description

  The present invention relates to a power transmission coil for transmitting power without contact.

  In recent years, a non-contact power feeding technology has been developed that does not have a direct electrical connection and transmits power in a non-contact manner. For example, Patent Document 1 proposes a non-contact charging apparatus that can charge a mobile phone simply by placing it on a cradle by applying this non-contact power feeding technique.

  In this non-contact charging device, when a metal foreign object such as a coin is placed on the upper part of the planar coil built in the cradle, an abnormal temperature rise of the metal foreign object occurs. Therefore, in the non-contact charging device of Patent Document 1, an abnormal temperature rise is detected by a temperature detection element.

  This detailed structure is shown in FIG. FIG. 9 is a diagram illustrating an installation position of a temperature detection element of a conventional non-contact charging apparatus.

  In FIG. 9, the temperature detection element 105 includes the cradle 101, the primary transmission coil 103, and the cradle 101 so that the center of the temperature detection element 105 is located at a position 5 mm away from the center of the primary transmission coil 103. Provided on the contact surface side. If the metal foreign matter 109 placed on the cradle 101 is present, the temperature rise can be accurately detected, and the supply of power to the primary transmission coil 103 can be immediately stopped and controlled. With such a configuration, it is possible to improve the safety of the non-contact charging device.

JP 2008-172874 A

  According to the contactless charging device of FIG. 9 described above, it is described that the temperature rise of the metal foreign object 109 can be accurately detected, but the metal foreign object 109 cannot be removed by the contactless charging device. As long as the foreign object 109 exists, there is a problem that power transmission (charging) is not performed. On the other hand, since the non-contact charging apparatus of Patent Document 1 charges a battery provided in a mobile phone terminal, if the metal foreign object 109 is placed on the cradle 101, the user himself / herself notices. Can be removed. However, when an object to be charged having a secondary transmission coil, such as an electric vehicle or a robot, self-runs on the primary transmission coil 103, the metal foreign object 109 is placed on the primary transmission coil 103. In this case, the user does not notice, the supply of power to the primary transmission coil 103 continues to stop, and charging may not be completed indefinitely.

  Moreover, although the structure which removes a foreign material using power sources, such as a motor, can also be considered, there existed a subject that the structure of the primary side transmission coil containing the said power source became complicated.

  The present invention solves the above-described conventional problems, and an object thereof is to provide a power transmission coil capable of removing foreign matter with a simple configuration.

  In order to solve the above-described conventional problems, a power transmission coil according to the present invention includes a planar coil, a foreign matter removing body that is provided on the upper surface side of the planar coil and is operable along the upper surface of the planar coil, and the foreign matter. A magnet attached to a position passing through the projection surface of the planar coil in the foreign object removing body when the removing body operates, and a power control circuit electrically connected to the planar coil, The control circuit controls the current supplied to the planar coil so that the magnet moves along the upper surface of the planar coil at least before starting the power transmission by the planar coil. It is made to operate.

  According to the power transmission coil of the present invention, before starting the power transmission, the foreign matter is simply controlled by controlling the current supplied to the planar coil so that the magnet provided on the foreign substance removing body moves along the upper surface of the planar coil. The removal body can be operated. Therefore, there is an effect that a power transmission coil capable of removing foreign matters with a simple configuration can be obtained without using a power source such as a motor.

Schematic perspective view when the foreign substance removing body of the power transmission coil in Embodiment 1 of the present invention moves from left to right Schematic perspective view when the foreign substance removal body of the power transmission coil in Embodiment 1 of the present invention moves from right to left Time-dependent characteristic view of the current supplied to the planar coil at the time of foreign matter removal of the power transmission coil in Embodiment 1 of the present invention Time-dependent characteristic view of the current supplied to the planar coil at the time of removing foreign matter from the power transmission coil in Embodiment 2 of the present invention Time-dependent characteristic diagram of the current supplied to the planar coil when the foreign substance is removed from the power transmission coil according to Embodiment 3 of the present invention The schematic perspective view at the time of the foreign material removal body of the power transmission coil in Embodiment 4 of this invention moving from left to right The schematic perspective view at the time of the foreign material removal body of the power transmission coil in Embodiment 6 of this invention moving from left to right The schematic perspective view at the time of the foreign material removal body of the power transmission coil in Embodiment 7 of this invention moving from left to right The figure which shows the installation position of the temperature detection element of the conventional non-contact charging device

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

(Embodiment 1)
FIG. 1 is a schematic perspective view when the foreign matter removing body of the power transmission coil according to Embodiment 1 of the present invention moves from left to right. FIG. 2 is a schematic perspective view when the foreign matter removing body of the power transmission coil according to the first embodiment of the present invention moves from right to left. FIG. 3 is a time characteristic diagram of the current supplied to the planar coil when the foreign substance is removed from the power transmission coil according to Embodiment 1 of the present invention.

  In FIG. 1, the power transmission coil 11 is provided on the upper surface side of the planar coil 13, the planar coil 13, and the foreign matter removing body 15 operable along the top surface of the planar coil 13. In addition, a magnet 17 attached at a position passing through the projection surface of the planar coil 13 in the foreign matter removing body 15 and a power control circuit 19 electrically connected to the planar coil 13 are provided.

  Then, the power control circuit 19 controls the current supplied to the planar coil 13 so that the magnet 17 moves along the upper surface of the planar coil 13 before starting the power transmission by at least the planar coil 13, thereby preventing the foreign matter. The removal body 15 is operated.

  Thereby, the power transmission coil 11 only controls the current supplied to the planar coil 13 so that the magnet 17 provided on the foreign substance removing body 15 moves along the upper surface of the planar coil 13 before starting the power transmission. Thus, the foreign substance removing body 15 can be operated. Therefore, it is possible to obtain the power transmission coil 11 capable of removing foreign matters with a simple configuration without using a power source such as a motor.

  Hereinafter, the configuration and operation of the first embodiment will be described more specifically.

  In FIG. 1, the planar coil 13 that is the primary side of the power transmission coil 11 has a configuration in which a litz wire is spirally wound on the same plane. The litz wire is fixed by a resin material (not shown). The planar coil 13 is electrically connected to the power control circuit 19. The power control circuit 19 has a function of, for example, converting commercial power into a frequency for power transmission and supplying it to the planar coil 13. Thereby, electric power can be supplied to a secondary coil (not shown) in a non-contact manner. The power control circuit 19 also includes a microcomputer (not shown) for controlling power transmission.

  The secondary coil is mounted on a device that receives power supply in a non-contact manner. This device is not particularly limited, but a moving body such as an electric vehicle or a robot is more difficult to detect foreign matter by the user, and thus the effect of the first embodiment can be easily obtained.

  A foreign substance removing body 15 is disposed on the upper surface of the planar coil 13. The foreign matter removing body 15 is for removing foreign matter on the planar coil 13, and a brush 21 is provided at a lower portion thereof, that is, a portion where the foreign matter removing body 15 is in contact with the upper surface of the planar coil 13. The brush 21 does not necessarily need to be in contact with the upper surface of the planar coil 13, but the contact can more reliably remove foreign matter. Further, instead of the brush 21, for example, a flat squeegee may be provided below the foreign matter removing body 15. Further, in the portion where the brush 21 is in contact with the upper surface of the planar coil 13, a fluorine-based resin is coated on the upper surface of the planar coil 13 in order to reduce friction between them.

  The foreign substance removing body 15 moves to the left and right along the upper surface of the planar coil 13. For this purpose, wheels 23 incorporating bearings (not shown) are attached to both ends of the foreign substance removing body 15 to reduce friction. Each wheel 23 is inserted into a recessed portion 27 of a guide rail 25 provided on the upper and lower sides with respect to the planar coil 13. With such a configuration, the foreign substance removing body 15 can move left and right along the upper surface of the planar coil 13 as the wheel 23 rotates in the recess 27.

  Further, a magnet 17 is attached to the foreign matter removing body 15. The magnet 17 is made of a permanent magnet, and is attached to a position passing through the projection surface of the planar coil 13 when the foreign matter removing body 15 moves along the upper surface of the planar coil 13. In the first embodiment, as shown in FIG. 1, a magnet 17 is attached to the center of the foreign matter removing body 15.

  Next, the operation of the power transmission coil 11 will be described.

  First, when the device on which the secondary coil is mounted faces the planar coil 13 and receives a power transmission request from the device by wireless communication, the power control circuit 19 starts power transmission by the planar coil 13. Then, the foreign matter removing body 15 is operated. Thereby, the foreign material removal body 15 moves from the left side of the planar coil 13 to the right side, as shown in FIG. Thereby, even if a foreign substance such as metal is placed on the planar coil 13, the foreign substance can be removed to the right end of the planar coil 13 by the brush 21 of the foreign substance removing body 15.

  Thereafter, as shown in FIG. 2, the power control circuit 19 performs an operation of returning the foreign matter removing body 15 from the right side to the left side of the planar coil 13. Thereby, since the foreign material removal body 15 reciprocates once on the planar coil 13, a foreign material can be removed more reliably.

  Here, the operation of the power control circuit 19 for making the foreign matter removing body 15 reciprocate once will be described with reference to FIG.

  FIG. 3 is a time characteristic diagram of the current supplied to the planar coil 13 when the power transmission coil 11 removes foreign matter. In FIG. 3, the horizontal axis represents time, and the vertical axis represents current.

  First, at time t0, the device on which the secondary coil is mounted is not facing the planar coil 13. Therefore, no current flows through the planar coil 13 and the current value is zero.

  Next, the planar coil 13 and the secondary coil face each other at time t1. At this time, the foreign substance removing body 15 is still at the left end of the planar coil 13, that is, at the operation start position. The power control circuit 19 receives a power transmission request from the device. In response to this, the power control circuit 19 supplies a predetermined current I0 to the planar coil 13 in order to move the foreign substance removing body 15 from the left side to the right side of the planar coil 13. Since the predetermined current I0 at this time is a direct current, a static magnetic field corresponding to the predetermined current I0 is generated on the planar coil 13.

  Thereby, the magnet 17 attached to the foreign matter removing body 15 is attracted to the static magnetic field, and the entire foreign matter removing body 15 attached with the magnet 17 moves along the upper surface of the planar coil 13. In order to move the foreign matter removing body 15 in this way, the direction of the magnet 17 is determined in advance and attached to the foreign matter removing body 15 so that the polarity of the magnet 17 attracts the static magnetic field. In addition, the predetermined current I0 that flows in the planar coil 13 necessary for moving the foreign substance removing body 15 as described above is obtained in advance in consideration of friction of the brush 21 and the wheel 23, and the power control circuit. 19 is stored in a memory (not shown) built in the apparatus.

  Here, if the static magnetic field is continuously generated, the foreign matter removing body 15 stops on the planar coil 13 due to a balance with the magnetic force of the magnet 17. Therefore, the power control circuit 19 stops the current supply to the planar coil 13 before the foreign substance removing body 15 stops, that is, at time t2 before the magnet 17 reaches the central portion of the planar coil 13. However, the foreign matter removing body 15 continues to move while decelerating toward the right side of the planar coil 13 due to the inertia of the operation so far. Then, it passes through the central portion of the planar coil 13.

  Next, at time t3 after the magnet 17 has passed the central portion of the planar coil 13, the power control circuit 19 controls the planar coil 13 to flow a predetermined current I0 again to generate the static magnetic field. As a result, since the magnet 17 has already passed through the central portion of the planar coil 13, the polarity of the magnet 17 with respect to the planar coil 13 is reversed at time t3 from that at time t1. Therefore, when the static magnetic field is generated at time t <b> 3, the magnet 17 receives a repulsive force so as to move away from the planar coil 13 and continues to move toward the right side of the planar coil 13. Thereby, it is possible to reduce the possibility that the foreign matter removing body 15 stops during the operation on the planar coil 13.

  Next, at time t <b> 4, the power control circuit 19 determines that the foreign matter removing body 15 has reached the right end of the planar coil 13, that is, the operation end position of the foreign matter removing body 15, and stops the current supply to the planar coil 13. As a result, the foreign matter removing body 15 stops at the right end of the planar coil 13 because the wheel 23 comes into contact with the right end of the recess 27 provided in the guide rail 25.

  At times t2, t3, and t4, when the foreign matter removing body 15 is actually moved, the above-described operation (the foreign matter removing body 15 moves without stopping from the left side to the right side along the upper surface of the planar coil 13) is obtained. As described above, time data at which the above operation is reproduced is determined by measuring in advance under various conditions. These time data are stored in the memory. Therefore, the power control circuit 19 can know the position of the foreign matter removing body 15 by monitoring the time after the start of the operation of the foreign matter removing body 15.

  In this way, by controlling the current (predetermined current I 0) supplied to the planar coil 13 by the power control circuit 19, the foreign matter removing body 15 can be operated from the left side to the right side of the planar coil 13.

  Next, since the foreign substance removing body 15 has moved to the right side of the planar coil 13, the power control circuit 19 reverses the time t1 in order to operate the foreign substance removing body 15 from the right side to the left side of the planar coil 13 at time t5. A predetermined current -I0 is supplied to the planar coil 13 in the direction. This is because the polarity of the magnet 17 is reversed between the left side and the right side of the planar coil 13.

  As a result, the foreign matter removing body 15 at the operation start position (in this case, the right end of the planar coil 13) starts operation from the right side to the left side of the planar coil 13 at time t5.

  Thereafter, the power control circuit 19 sets the current to the planar coil 13 to 0 at time t6 before the magnet 17 reaches the central portion of the planar coil 13, and then after the magnet 17 exceeds the central portion of the planar coil 13. At time t7, a predetermined current −I0 is caused to flow through the planar coil 13 again, similarly to time t5. Then, at time t8 when the foreign matter removing body 15 reaches the left end of the planar coil 13, that is, the operation end position of the foreign matter removing body 15, the power control circuit 19 sets the current to the planar coil 13 to zero. Thus, by controlling the current supplied to the planar coil 13 by the power control circuit 19, the foreign matter removing body 15 can be operated from the right side to the left side of the planar coil 13.

  Times t6, t7, and t8 are determined in advance and stored in the memory in the same manner as times t2, t3, and t4. Therefore, also in the operation of returning the foreign matter removing body 15, the power control circuit 19 can know the position of the foreign matter removing body 15 by monitoring the time after the start of the operation of the foreign matter removing body 15.

  The operation of the foreign matter removing body 15 is summarized as follows. When the power control circuit 19 moves the magnet 17 along the upper surface of the planar coil 13, the magnet 17 is not moved from the operation start position to the central portion of the planar coil 13, and the magnet 17 is planar. A current is supplied to the planar coil 13 from the time when it passes the central portion of the coil 13 until it reaches the operation end position.

  Thereby, since the foreign material removal body 15 can be moved once and reciprocated along the upper surface of the planar coil 13, foreign material removal can be more reliably performed with a simple configuration.

  Thereafter, the power control circuit 19 starts to supply power to the device on which the secondary coil is mounted. At this time, since a high-frequency alternating current flows through the planar coil 13, the direction and magnitude of the magnetic force generated in the planar coil 13 changes at high speed. Therefore, since the static magnetic field is not generated, the magnet 17 hardly moves during the power supply of the planar coil 13. Therefore, the foreign substance removing body 15 does not hinder power supply.

  With the above configuration and operation, the power transmission coil 11 supplies the current supplied to the planar coil 13 so that the magnet 17 provided on the foreign matter removing body 15 moves along the upper surface of the planar coil 13 before starting the power transmission. The foreign matter removing body 15 can be operated only by controlling the above. Therefore, it is possible to obtain the power transmission coil 11 capable of removing foreign matters with a simple configuration without using a power source such as a motor.

  Note that the time-dependent change diagram of the current flowing through the planar coil 13 shown in FIG. 3 is an example, and a predetermined current value and each time may be determined in advance according to the installation location of the power transmission coil 11 and the surrounding environment. .

  Further, in FIG. 3, the absolute value of the predetermined current is the same value (I0), which is from time t1 to time t2, from time t3 to time t4, from time t5 to time t6, and from time t7 to time t8. Each may be determined as an optimal current value. At this time, the current values may be different values.

  Further, the interval between time t4 and time t5 shown in FIG. 3 may be set arbitrarily. That is, as described in the first embodiment, in order to reciprocate the foreign matter removing body 15 once, the interval is shortened. Thereby, the certainty of foreign substance removal can be increased. On the other hand, when the foreign matter removing body 15 operates in only one direction and the foreign matter is sufficiently removed from the environment or the environment, the time t5 may be set as the next time when the power transmission coil 11 is used.

  In the first embodiment, the foreign matter removing body 15 is operated before the power transmission by the planar coil 13 is started. In addition, the power control circuit 19 also performs the power transmission when the power is not transmitted. The foreign matter removing body 15 may be operated. For example, the power control circuit 19 periodically operates the foreign matter removing body 15 when the power transmission coil 11 is not used. Thereby, even in an environment where a large number of foreign matters are placed on the planar coil 13 when not in use, the foreign matter can be more reliably removed periodically.

  In the first embodiment, a permanent magnet is used as the magnet 17, but an electromagnet may be used. In this case, the structure is slightly complicated because wiring is required compared to the permanent magnet. However, when the magnetic metal foreign matter adheres to the magnet 17, the magnetic metal foreign matter can be easily removed from the magnet 17 by turning off the energization of the electromagnet as soon as the foreign matter removing body 15 reaches the operation end position. Therefore, it is desirable to use an electromagnet as the magnet 17 in an environment where there are many magnetic metal foreign objects.

  In the first embodiment, as shown in FIGS. 1 and 2, the magnet 17 is attached to the center in the longitudinal direction of the foreign matter removing body 15. However, the present invention is not limited to this, and the foreign matter removing body 15 is not limited thereto. May be attached to any position in the longitudinal direction as long as it passes through the projection surface of the planar coil 13 in the foreign substance removing body 15. However, when it is attached at a position deviated from the center, the static magnetic field received by the magnet 17 from the planar coil 13 is weakened, and accordingly, a predetermined current is increased or the magnetic force of the magnet 17 is increased. Adjustment is required.

  In the first embodiment, the number of magnets 17 is one. However, the present invention is not limited to this, and a plurality of magnets 17 may be attached to the foreign matter removing body 15.

(Embodiment 2)
FIG. 4 is a time characteristic diagram of the current supplied to the planar coil when the foreign substance is removed from the power transmission coil according to Embodiment 2 of the present invention.

  Since the configuration of the second embodiment is the same as that of the first embodiment, detailed description thereof is omitted. Since the feature of the second embodiment is the operation, the operation will be described with a focus on differences from the first embodiment.

  In FIG. 4, when the power control circuit 19 moves the magnet 17 along the upper surface of the planar coil 13, the magnet 17 moves to the planar coil 13 from the operation start position to the central portion of the planar coil 13. Control is performed so that the absolute value of the supplied current gradually decreases from the initial current value. Then, the power control circuit 19 causes the absolute value of the current supplied to the planar coil 13 to gradually increase to the final current value until the magnet 17 reaches the operation end position from the central portion of the planar coil 13. Control.

  As a result, the magnet 17 can operate more smoothly along the upper surface of the planar coil 13, so that foreign matter removal by the foreign matter removing body 15 is reduced, and more reliable foreign matter removal is possible with a simple configuration. Become.

  Hereinafter, detailed operations in the second embodiment will be described with reference to FIG. In FIG. 4, the horizontal axis represents time, and the vertical axis represents the current flowing through the planar coil 13.

  First, time t10 in FIG. 4 is in the same state as time t0 in FIG. Therefore, the current value is zero.

  Next, at time t11, the planar coil 13 and the secondary coil face each other, and the power control circuit 19 receives a power transmission request from the device. In response to this, the power control circuit 19 causes the current of the initial current value I1 to flow through the planar coil 13 in order to move the foreign substance removing body 15 from the left side to the right side of the planar coil 13. As a result, a magnetic field corresponding to the initial current value I1 is generated on the planar coil 13.

  As a result, the magnet 17 attached to the foreign matter removing body 15 is attracted to the magnetic field, and the entire foreign matter removing body 15 attached with the magnet 17 moves along the upper surface of the planar coil 13. Note that the polarity of the magnet 17 for moving the foreign substance removing body 15 is determined in the same manner as in the first embodiment.

  From time t11 to time t12, that is, as described in the balloon in FIG. 4, the power of the magnet 17 from the operation start position (the left end of the planar coil 13) to the central portion of the planar coil 13 is The control circuit 19 performs control so that the absolute value of the current supplied to the planar coil 13 gradually decreases. This is due to the following reason.

  When the foreign object removing body 15 is at the left end (operation start position) of the planar coil 13, the distance between the magnet 17 and the planar coil 13 is the longest. Further, at time t11, it is necessary to start moving the foreign matter removing body 15 in consideration of the friction of the brush 21 and the wheel 23. Therefore, the initial current value I1 to the planar coil 13 is a current value having a large absolute value. As a result, the movement of the foreign substance removing body 15 can be made more reliable, and by increasing the magnitude of the magnetic field, the force attracted by the magnet 17 is increased, and the foreign substance removing body 15 is operated reliably. You can start. Note that the initial current value I1 is determined in advance and stored in the memory so that the foreign substance removing body 15 can operate as described above.

  Thereafter, the power control circuit 19 controls the absolute value of the current flowing through the planar coil 13 to gradually decrease with time as shown from time t11 to time t12 in FIG. As a result, the force received by the magnet 17 from the planar coil 13 is almost uniform, since the increase in force due to the closeness of the two and the decrease in force due to the decrease in current are offset. In other words, the absolute value of the current of the planar coil 13 is controlled to gradually decrease so that the force that the magnet 17 receives from the planar coil 13 becomes substantially uniform. As a result, the foreign substance removing body 15 can operate more smoothly on the upper surface of the planar coil 13 with equal force. Accordingly, the possibility of losing foreign matter is reduced.

  Next, at time t <b> 12, the magnet 17 reaches the center portion of the planar coil 13, and then moves away from the planar coil 13. In response to this, the power control circuit 19 supplies the planar coil 13 with the magnet 17 from the central portion of the planar coil 13 to the operation end position, as shown from time t12 to time t13 in FIG. Control is performed so that the absolute value of the current gradually increases to the final current value I2. As a result, the decrease in the force received by the magnet 17 due to the magnet 17 moving away from the planar coil 13 is offset by increasing the magnitude of the magnetic field by increasing the current flowing through the planar coil 13. Therefore, the force received from the planar coil 13 by the magnet 17 from time t12 to time t13 is substantially uniform, and the foreign matter removing body 15 operates more smoothly from the left side to the right side of the planar coil 13 with uniform force. Can do. Therefore, the possibility of losing foreign matter over the entire planar coil 13 is reduced.

  Next, when the foreign matter removing body 15 reaches the operation end position (the right end of the planar coil 13) at time t13, the power control circuit 19 changes the current to the planar coil 13 from the final current value I2 to zero. Thereby, the foreign substance removal body 15 stops at the operation end position. Here, the absolute value of the final current value I2 is made smaller than the initial current value I1. This is because it is necessary to apply a greater force to the magnet 17 than when the foreign matter removing body 15 is stopped in consideration of the friction of the brush 21 and the wheel 23 when starting to move the foreign matter removing body 15. is there.

  The current pattern from time t11 to time t13 is the above-described operation (the foreign matter removing body 15 smoothly moves from the left side to the right side along the upper surface of the planar coil 13) when the foreign matter removing body 15 is actually moved. As obtained, the measurement is performed in advance under various conditions, and the operation is determined to be reproduced. And the time t11, t12, t13 at the time of operating the foreign material removal body 15 with the electric current pattern is measured, and is previously determined as time data. These time data are stored in the memory.

  Thus, by controlling the current supplied to the planar coil 13 by the power control circuit 19, the foreign matter removing body 15 can be operated from the left side to the right side of the planar coil 13.

  Next, the case where the foreign matter removing body 15 is operated from the right side to the left side of the planar coil 13 will be described. As described in the first embodiment, the current pattern to the planar coil 13 in this case is a current pattern in which the polarity of the magnet 17 is inverted between the left side and the right side of the planar coil 13 and the sign of the current is reversed. .

  As a result, the foreign matter removing body 15 at the operation start position (in this case, the right side of the planar coil 13) starts operation from the right side to the left side of the planar coil 13 at time t14. The current flowing through the planar coil 13 at this time is the initial current value −I1.

  Thereafter, as shown from time t14 to time t15 in FIG. 4, the power control circuit 19 supplies the current supplied to the planar coil 13 from the operation start position to the central portion of the planar coil 13. Is controlled so as to gradually decrease from the absolute value of the initial current value −I1. Then, after time t15 after the magnet 17 has passed over the central portion of the planar coil 13, the power control circuit 19 is in the plane until the time t16 when the magnet 17 reaches the operation end position from the central portion of the planar coil 13. Control is performed so that the absolute value of the current supplied to the coil 13 gradually increases. Thereafter, at time t16 when the foreign matter removing body 15 reaches the left end of the planar coil 13, that is, the operation end position of the foreign matter removing body 15, the power control circuit 19 changes the current to the planar coil 13 from the final current value −I2 to zero. . Thus, by controlling the current supplied to the planar coil 13 by the power control circuit 19, the foreign matter removing body 15 can be operated from the right side to the left side of the planar coil 13.

  Note that the current pattern from time t14 to time t16 shown in FIG. 4 is determined in the same manner as the current pattern from time t11 to time t13, and is stored in the memory. Further, times t14, t15, and t16 are determined in advance and stored in the memory in the same manner as times t11, t12, and t13. Therefore, the power control circuit 19 can know the position of the foreign matter removing body 15 by monitoring the time after the start of the operation of the foreign matter removing body 15.

  The operation of the foreign matter removing body 15 is summarized as follows. When the power control circuit 19 moves the magnet 17 along the upper surface of the planar coil 13, the current that the magnet 17 supplies to the planar coil 13 from the operation start position to the central portion of the planar coil 13 is detected. The absolute value of the current supplied to the planar coil 13 from the central portion of the planar coil 13 to the operation end position is controlled so that the absolute value gradually decreases from the initial current value. Until it gradually increases.

  Thereby, since the foreign material removal body 15 can be moved back and forth smoothly along the upper surface of the planar coil 13, foreign material removal can be more reliably performed with a simple configuration.

  With the above configuration and operation, the power transmission coil 11 can move the magnet 17 more smoothly along the upper surface of the planar coil 13, so that foreign matter removal by the foreign matter removing body 15 is reduced, and the configuration is simple. Thus, it is possible to more reliably remove foreign matter.

  Note that the temporal change diagram of the current flowing through the planar coil 13 shown in FIG. 4 is an example, and the initial current value, the final current value, and each time are determined in advance according to the installation location of the power transmission coil 11 and the surrounding environment. That's fine.

  Furthermore, in the current pattern shown in FIG. 4, the current linearly changes with time in a portion where the absolute value of the current gradually decreases or greatly changes. If necessary for operation, a non-linear current pattern such as an exponential change may be used.

  Further, in the time-dependent change diagram of the current flowing through the planar coil 13 in FIG. 4, the current pattern is a current pattern that slightly flows at time t12 and time t15 when the magnet 17 reaches the central portion of the planar coil 13. If it is necessary to smoothly move the foreign substance removing body 15 depending on the structure of the transmission coil 11, the installation location, and the surrounding environment, as in the first embodiment, when the magnet 17 reaches the central portion of the planar coil 13. A period for setting the current to 0 may be provided.

  In the second embodiment, the absolute value of the final current value I2 is set to be smaller than the absolute value of the initial current value I1, but this is necessary if the foreign object removal body 15 is smoothly moved. The same value may be used, or the absolute value of the final current value I2 may be larger than the absolute value of the initial current value I1.

  Further, the interval between time t13 and time t14 shown in FIG. 4 may be arbitrarily set similarly to the interval between time t4 and time t5 in the first embodiment.

  In the second embodiment, as in the first embodiment, the foreign matter removing body 15 is operated before the power transmission by the planar coil 13 is started. In addition, the power control circuit 19 is The foreign matter removing body 15 may be operated even when power transmission is not performed. Thereby, in the environment where many foreign matters are placed on the planar coil 13 when not in use, foreign matter removal can be performed more reliably.

  In the second embodiment, an electromagnet may be used as the magnet 17 as in the first embodiment.

  Further, the temporal change characteristic of the current supplied to the planar coil 13 shown in the first and second embodiments is not limited to the rectangular wave shown in FIG. 3 and the linear change shown in FIG. As long as the removal body 15 can be moved left and right, any time-varying characteristics may be used.

(Embodiment 3)
FIG. 5 is a time characteristic diagram of the current supplied to the planar coil when the foreign substance is removed from the power transmission coil according to the third embodiment of the present invention.

  Since the configuration of the third embodiment is the same as that of the first embodiment, detailed description thereof is omitted. Since the feature of the third embodiment is the operation, the operation will be described with a focus on differences from the first embodiment.

  In FIG. 5, before supplying the current for moving the magnet 17 along the upper surface of the planar coil 13 to the planar coil 13, the power control circuit 19 switches the predefined current to the planar coil 13 by switching between positive and negative times. Supply.

  As a result, the magnet 17 is swung to the left and right at the operation start position in accordance with the positive / negative switching of the predetermined current. In this state, the power control circuit 19 continues to supply a predetermined current I0 for moving the magnet 17 along the upper surface of the planar coil 13 to the planar coil 13, so that the friction is large when the foreign matter removing body 15 starts to move. In addition, it is possible to increase the possibility of moving the foreign matter removing body 15 with certainty.

  Hereinafter, detailed operations in the third embodiment will be described with reference to FIG. In FIG. 5, the horizontal axis represents time, and the vertical axis represents the current flowing through the planar coil 13. Also, the same time as in FIG. 1 is assigned to the same time as the time on the horizontal axis, and the description of the details of the operation at that time is omitted.

  First, when the planar coil 13 and the secondary coil face each other at time t21 in FIG. 5, the power control circuit 19 receives a power transmission request from the device. In response to this, the power control circuit 19 causes the predetermined current Is to flow through the planar coil 13.

  Thereafter, after a short period (for example, 0.5 seconds), the power control circuit 19 supplies the predetermined current Is as a negative current (−Is) to the planar coil 13.

  Next, after a short period (for example, 0.5 seconds), the power control circuit 19 supplies the predetermined current −Is as a positive current again (Is) to the planar coil 13.

  Thereafter, as described above, the power control circuit 19 repeatedly supplies the predetermined current Is to the planar coil 13 while switching between positive and negative. By this operation, the magnet 17 is applied with a magnetic force that is shaken to the left and right, and the foreign matter removing body 15 also moves slightly to the left and right.

  After a predetermined number of times of switching (five times in FIG. 5), the power control circuit 19 passes a predetermined current I0 through the planar coil 13 at time t1. At this time, since the foreign substance removing body 15 has already been moved slightly to the left and right, the friction when the foreign substance removing body 15 starts to move is reduced. In this state, by passing a predetermined current I0 through the planar coil 13, the possibility of moving the foreign matter removing body 15 reliably increases.

  The operation after time t1 is the same as that in the first embodiment. Therefore, the foreign matter removing body 15 reciprocates once on the planar coil 13.

  By operating in this way, the friction between the brush 21 and the upper surface of the planar coil 13 and the friction between the wheel 23 and the guide rail 25 are large when the foreign substance removing body 15 starts to move, and as shown in FIG. Thus, even if a predetermined current I0 flows suddenly through the planar coil 13, the possibility that the foreign matter removing body 15 does not move can be reduced.

  In FIG. 5, the absolute value of the predetermined current Is is larger than the absolute value of the predetermined current I0. If the configuration of the power transmission coil 11 is such that the foreign substance removing body 15 may not move only with the predetermined current I0, a current absolute value larger than the absolute value of the predetermined current I0 is determined as the predetermined current Is. This is because there is a high possibility that the foreign substance removing body 15 cannot be moved slightly to the left and right if not set.

  The specific absolute value of the predetermined current Is and the absolute value of the predetermined current I0 are experimentally determined in advance as values that are likely to cause the foreign object removal body 15 to operate. Further, the period and the predetermined number of times for supplying the predetermined current Is are not limited to the above-described 0.5 seconds or 5 times in order, but are experimental in advance as values that are likely to cause the foreign matter removing body 15 to operate. Make a decision. Therefore, depending on the configuration of the power transmission coil 11 (particularly, the magnitude of friction), the period during which the optimum default current Is flows, and the predetermined number of times, the absolute value of the default current Is is not necessarily determined to be larger than the absolute value of the predetermined current I0. However, the values may not be the same.

  With the above configuration and operation, the power control circuit 19 continues to move the magnet 17 along the upper surface of the planar coil 13 in a state where the magnet 17 is swung to the left and right according to the positive / negative switching of the predetermined current at the operation start position. A predetermined current I 0 for moving the plate is supplied to the planar coil 13. Therefore, even if the friction is large when the foreign matter removing body 15 starts to move, it is possible to reliably increase the possibility of moving the foreign matter removing body 15. Therefore, the foreign matter can be more reliably removed with a simple configuration.

  In the third embodiment, the current is supplied to the planar coil 13 with the same current pattern as in the first embodiment after time t1, but this is after time t11 in FIG. 4 of the second embodiment. A current pattern may be used. Also in this case, the same effect as in the third embodiment can be obtained.

  In the third embodiment, the case where the power control circuit 19 continuously reciprocates the foreign matter removing body 15 has been described. However, when the foreign matter removing body 15 is operated only in one direction, the foreign matter removing body 15 is shown in FIG. Before moving from the right side to the left side, that is, immediately before time t5 in FIG. 5, the power control circuit 19 supplies a predetermined current for a predetermined number of times by switching between positive and negative, similarly to time t21. Thereby, even when moving the foreign matter removing body 15 to either side, the possibility of moving the foreign matter removing body 15 can be increased with certainty.

(Embodiment 4)
FIG. 6 is a schematic perspective view when the foreign substance removing body of the power transmission coil according to the fourth embodiment of the present invention moves from left to right.

  In the configuration of the fourth embodiment, the same components as those of the first embodiment are denoted by the same reference numerals, detailed description thereof is omitted, and the configuration and operation that are characteristic in the fourth embodiment will be mainly described.

  In FIG. 6, the power transmission coil 11 further includes a position detection unit 28 of the foreign matter removing body 15 that is electrically connected to the power control circuit 19. Then, when the power control circuit 19 moves the magnet 17 along the upper surface of the planar coil 13, the power control circuit 19 controls the current supplied to the planar coil 13 based on the position of the foreign substance removing body 15 detected by the position detection unit 28. .

  As a result, the power control circuit 19 can accurately detect the position of the foreign substance removal body 15 from the output of the position detection unit 28, so that the control accuracy of the current pattern as shown in FIGS. More reliable foreign matter removal is possible.

  Hereinafter, a detailed configuration in the fourth embodiment will be described with reference to FIG.

  In FIG. 6, the position detection unit 28 is arranged on one side of the guide rail 25 of the power transmission coil 11 (the back guide rail 25 in FIG. 6). The position detection unit 28 is for detecting the position of the foreign substance removing body 15 on the guide rail 25, and specifically, a configuration in which a plurality of micro switches are provided in a portion through which the wheel 23 of the guide rail 25 passes. It is said. The positions of these microswitches correspond to the positions where the wheel 23 passes at times t1, t2, t3, and t4 in FIG. 3 of the first embodiment. That is, when the foreign matter removing body 15 is operated based on a predetermined current pattern as shown in FIG. 3, the foreign matter removing body 15 can operate on the planar coil 13 from left to right and from right to left. The positions through which the wheels 23 pass at times t1, t2, t3, and t4 are determined, and the microswitches are arranged at these positions, respectively. Here, an example in which four micro switches are provided is shown, and these are collectively referred to as a position detection unit 28. The position detection unit 28 is electrically connected to the power control circuit 19. Therefore, the power control circuit 19 can know the position of the foreign substance removing body 15 by taking the output from the position detection unit 28.

  Next, operation | movement of the electric power transmission coil 11 of such a structure is demonstrated. It is assumed that the current pattern to the planar coil 13 when operating the foreign matter removing body 15 is that of FIG.

  In FIG. 3, at the operation start position (left end) at time t 0, the foreign substance removing body 15 has not yet operated, so only the microswitch provided at the left end of the guide rail 25 is pushed by the wheel 23 and turned on. . Therefore, the power control circuit 19 determines that the foreign substance removing body 15 is in the operation start position because the leftmost micro switch of the four micro switches is on.

  In this state, when the power control circuit 19 receives a power transmission request from the device at time t1, the power control circuit 19 passes a predetermined current I0 through the planar coil 13. As a result, the foreign matter removing body 15 moves to the right along the upper surface of the planar coil 13.

  The power control circuit 19 monitors the time in the first embodiment after the operation of the foreign substance removing body 15 is started. On the other hand, the power control circuit 19 monitors the output of the position detection unit 28 in the fourth embodiment. At time t2 in FIG. 3, the wheel 23 turns on the second micro switch from the left. The power control circuit 19 turns off a predetermined current I0 to the planar coil 13 by detecting the output.

  Thereafter, when the foreign substance removing body 15 reaches the position at time t3, the wheel 23 turns on the third micro switch from the left, so that the power control circuit 19 detects the output to the planar coil 13. A predetermined current I0 is supplied again.

  Finally, when the foreign substance removing body 15 reaches the position at time t4, that is, the operation end position (right end), the wheel 23 turns on the micro switch at the right end (fourth from the left), so the power control circuit 19 By detecting the output, a predetermined current I0 to the planar coil 13 is turned off.

  Thereafter, from time t5 to time t8, the power control circuit 19 operates the foreign matter removing body 15 from right to left along the upper surface of the planar coil 13 in the same manner as described above.

  As described above, the power control circuit 19 detects the actual position of the foreign substance removing body 15 from the output of the position detection unit 28, and controls the predetermined current I0 supplied to the planar coil 13 based on the position. The accuracy of control timing is improved. As a result, although it is necessary to provide the position detection unit 28, the foreign substance removal body 15 can be operated more reliably.

  In addition, although the structure using the said micro switch for the position detection part 28 was demonstrated here, it is not limited to the said micro switch, What is necessary is just to be able to detect the position of the foreign material removal body 15. Specifically, for example, the position detection unit 28 may be configured by incorporating a plurality of combinations of light emitting diodes and phototransistors into the guide rail 25. In this case, since the position detection unit 28 is based on an optical detection principle, the position of the foreign substance removal body 15 can be detected in a non-contact manner. Accordingly, the friction between the microswitch and the wheel 23 is eliminated, and the smooth operation of the foreign matter removing body 15 becomes possible.

  With the above configuration and operation, the power control circuit 19 can accurately detect the position of the foreign matter removing body 15 from the output of the position detection unit 28, so that the current pattern control accuracy can be improved and more reliable foreign matter removal can be achieved. Is possible.

  In the fourth embodiment, the current pattern has been described as shown in FIG. 3, but the present invention is not limited to this, and the configuration and operation of the fourth embodiment are similar to the current pattern shown in FIG. 4 and FIG. Alternatively, the present invention may be applied to a current pattern obtained by combining FIG. 4 and FIG. Here, in the case of the current pattern in FIG. 4 or the current pattern in which FIG. 4 and FIG. 5 are combined, the position detecting position on the guide rail 25 is the position where the foreign matter removing body 15 reaches at time t11, t12, and t13. Therefore, the number of the microswitches may be three.

  Thus, in the case of a relatively complicated current pattern as shown in FIG. 3 or FIG. 5, it is necessary to provide a large number of the microswitches for each position corresponding to the current switching, as shown in FIG. In the case of a relatively simple current pattern, the required number of microswitches is reduced. Therefore, the number of the microswitches may be appropriately determined based on a current pattern that is obtained in advance and that reliably moves the foreign matter removing body 15.

(Embodiment 5)
Since the configuration of the power transmission coil 11 in the fifth embodiment is the same as that of FIG. 6 in the fourth embodiment, the detailed description thereof will be omitted, and the description will focus on the operations that are characteristic in the fifth embodiment. .

  The power transmission coil 11 further includes a position detection unit 28 of the foreign matter removing body 15 that is electrically connected to the power control circuit 19. Then, the power control circuit 19 determines that the relationship between the position of the foreign substance removing body 15 detected by the position detection unit 28 and the elapsed time from the start of the operation of the foreign substance removing body 15 is a predetermined value during normal operation of the foreign substance removing body 15. If the relationship is different, the operation of the foreign matter removing body 15 is determined to be abnormal, and the supply of current to the planar coil 13 is stopped.

  As a result, the power control circuit 19 can determine an abnormality in the operation of the foreign matter removing body 15. When the abnormality is determined to be abnormal, the supply of current to the planar coil 13 is stopped. It is possible to reduce the possibility that a current will continue to flow. Further, the power control circuit 19 notifies the user of the abnormal operation of the foreign matter removing body 15, so that the user can remove foreign matter (for example, heavy foreign matter) that cannot be removed by the foreign matter removing body 15. As a result, reliable foreign matter removal is possible.

  Hereinafter, detailed operations in the fifth embodiment will be described. Here, it is assumed that the foreign matter removing body 15 is operated based on the current pattern in FIG.

  The power control circuit 19 supplies a predetermined current I0 to the planar coil 13 at time t1 in FIG. At the same time, the power control circuit 19 measures the elapsed time after the time t1, that is, the elapsed time from the start of the operation of the foreign matter removing body 15.

  Thereafter, if the foreign substance removing body 15 is operating normally, the wheel 23 reaches the second microswitch from the left in FIG. 6 at time t2. As a result, the second microswitch is turned on.

  Thereby, the power control circuit 19 can know that the position of the foreign substance removing body 15 is at the position of the second microswitch. Then, as shown at time t2 in FIG. 3, the current to the planar coil 13 is set to zero.

  Thereafter, the operation after time t2 described in the first embodiment is performed.

  On the other hand, it is assumed that the foreign matter removing body 15 comes into contact with, for example, a heavy foreign matter and cannot move between time t1 and time t2. In this case, even if the time from time t1 to time t2 elapses, the second micro switch is not turned on. Since the power control circuit 19 measures the elapsed time from the start of the operation of the foreign matter removing body, the foreign matter is not turned on if the second microswitch does not turn on even after the time from time t1 to time t2. It is determined that the operation of the removal body 15 is abnormal.

  In this case, the power control circuit 19 stops supplying current to the planar coil 13 after time t2. Thereby, it is possible to reduce the possibility that a current continues to flow through the planar coil 13 even when there is an abnormality.

  Further, when the power control circuit 19 determines the abnormality, the power control circuit 19 immediately notifies the user of the abnormality of the foreign matter removing body 15. As a notification means (not shown), a warning sound, an abnormal warning light, display on a screen, or the like can be applied.

  In the state in which the abnormality is reported, the power supply to the planar coil 13 is stopped as described above, so that power transmission to the secondary coil cannot be performed. Therefore, the user removes the foreign matter on the planar coil 13 based on the abnormality notification from the power control circuit 19. Therefore, the user can surely remove the foreign matter.

  Further, the notifying means notifies information for urging foreign matter removal and instructs the foreign matter removing body 15 to return to the operation start position (left end in FIG. 6). Thereby, when removing the foreign matter, the user manually returns the foreign matter removing body 15 to the operation start position in accordance with the instruction from the notification means. At this time, as described in the first embodiment, the foreign matter removing body 15 is configured to reduce friction during operation and has no power source such as a motor. 15 can be returned to the operation start position.

  Thereby, since the above-described heavy foreign matter is removed, the power control circuit 19 can start power transmission after operating the foreign matter removing body 15 again.

  In the above description, the case where the power control circuit 19 determines that the foreign matter removing body 15 is abnormal while the foreign matter removing body 15 is between time t1 and time t2 has been described. Thus, the abnormality of the foreign substance removing body 15 is determined at other times. The operation of the power control circuit 19 is summarized as follows.

  In the power control circuit 19, the relationship between the position of the foreign matter removing body 15 detected by the position detection unit 28 and the elapsed time from the start of the operation of the foreign matter removing body 15 is a predetermined relationship during normal operation of the foreign matter removing body 15. Otherwise, it is determined that the operation of the foreign substance removing body 15 is abnormal.

  Note that the predetermined relationship is obtained in advance as to how long the foreign substance removing body 15 will reach when the foreign substance removing body 15 operates normally. This predetermined relationship includes a time error assumed in advance. Specifically, in the case of FIG. 3, when the time from time t1 to time t2 elapses, the second microswitch in FIG. 6 is turned on, and when the time from time t1 to time t3 elapses, FIG. The third micro switch of FIG. 6 is turned on, and when the time from time t1 to time t4 has elapsed, the relationship that the fourth micro switch of FIG. 6 is turned on is a predetermined relationship including a time error. To do. Similarly, a predetermined relationship is obtained in advance for time t5 to time t8. These predetermined relationships are stored in the memory of the power control circuit 19.

  Further, as a factor that causes the foreign matter removing body 15 to become abnormal, in addition to the case of the heavy foreign matter described above, if the foreign matter removing body 15 is not heavy but the operation of the foreign matter removing body 15 is slower than usual, Examples include a case where dust is caught and the foreign matter removing body 15 cannot operate. Also in these cases, the foreign matter can be reliably removed when the user responds to the abnormality.

  With the above configuration and operation, the power control circuit 19 can determine an abnormality in the operation of the foreign matter removing body 15, and if it is determined as abnormal, the supply of current to the planar coil 13 is stopped. In addition, the possibility of continuing the current flow to the planar coil 13 can be reduced. Further, the power control circuit 19 notifies the user of the abnormal operation of the foreign matter removing body 15, so that the user can remove foreign matters that cannot be removed by the foreign matter removing body 15. As a result, reliable foreign matter removal is possible.

  In the fifth embodiment, the power control circuit 19 uses the output of the position detection unit 28 to determine the abnormality of the foreign matter removing body 15, but this configuration includes the configuration of the fourth embodiment, that is, A configuration may be combined in which the current supplied to the planar coil 13 is controlled based on the position of the foreign substance removing body 15 based on the output of the position detection unit 28. In this case, the accuracy of current control is improved, and abnormality determination of the foreign matter removing body 15 is possible.

  Further, in the fifth embodiment, the description has been made based on the current pattern of the first embodiment (FIG. 3). However, this is the current pattern configuration shown in FIG. 4, FIG. 5, or a combination of FIG. The abnormality determination configuration of the fifth embodiment may be added.

(Embodiment 6)
FIG. 7 is a schematic perspective view when the foreign matter removing body of the power transmission coil according to the sixth embodiment of the present invention moves from left to right.

  Since the operation in the sixth embodiment is the same as that in the first embodiment or the second embodiment, detailed description thereof is omitted. Since the feature of the sixth embodiment is the configuration, the configuration will be described with a focus on differences from the first embodiment.

  In FIG. 7, the power transmission coil 11 includes a brush 21 at the portion of the foreign matter removing body 15 that contacts the upper surface of the planar coil 13, and the upper surface of the planar coil 13 substantially includes the operation direction of the foreign matter removing body 15. A groove 29 is provided in parallel.

  Thereby, when the magnet 17 moves along the upper surface of the planar coil 13, the brush 21 is in contact with the groove 29, so that fine foreign matter is scraped out along the groove 29 by the brush 21. As a result, the removal of foreign matter by the foreign matter removing body 15 is further reduced, and the foreign matter can be more reliably removed with a simple configuration.

  Hereinafter, a detailed configuration of the sixth embodiment will be described with reference to FIG. In FIG. 7, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 7, a characteristic configuration is that a groove 29 is provided on the upper surface of the planar coil 13. The groove 29 is provided substantially parallel to the upper surface of the planar coil 13 in the direction of operation of the foreign matter removing body 15 (left-right direction in FIG. 7). The upper surface of the planar coil 13 is made of resin as described in the first embodiment, and a groove 29 is formed by processing a part of the upper surface. Here, “substantially parallel” is defined as being parallel to the lateral direction in which the foreign substance removing body 15 operates within the range of the operation error of the foreign substance removing body 15 and the processing accuracy of the grooves 29.

  The brush 21 contacts the groove 29. As a result, the power control circuit 19 operates the foreign substance removing body 15 as described in the first and second embodiments, whereby a part of the tip of the brush 21 moves while entering the groove 29. Therefore, the fine foreign matter that has entered the groove 29 is removed as the brush 21 is scraped off, so that the possibility of the foreign matter being missed can be reduced.

  When the foreign matter removing body 15 is reciprocated once, the brush 21 passes through the groove 29 twice, so that fine foreign matters can be removed more reliably.

  Further, the groove 29 is processed integrally with the resin on the upper portion of the planar coil 13, but the present invention is not limited to this. For example, a configuration in which a plate provided with the groove 29 is fixed to the upper surface of the planar coil 13 is also possible. Good.

  With the above configuration and operation, when the magnet 17 operates along the upper surface of the planar coil 13, the brush 21 is in contact with the groove 29, so that fine foreign matter is scraped out along the groove 29 by the brush 21. . As a result, the removal of foreign matter by the foreign matter removing body 15 is further reduced, and the foreign matter can be more reliably removed with a simple configuration.

(Embodiment 7)
FIG. 8 is a schematic perspective view when the foreign matter removing body of the power transmission coil according to the seventh embodiment of the present invention moves from left to right.

  Since the operation in the seventh embodiment is the same as that in the first embodiment or the second embodiment, detailed description thereof is omitted. Since the feature of the seventh embodiment is the configuration, the configuration will be described with a focus on differences from the first embodiment.

  In FIG. 8, the power transmission coil 11 has a configuration in which a cover 31 operable along the upper surface of the planar coil 13 is attached to the foreign matter removing body 15.

  Accordingly, the cover 31 can be opened and closed by the operation of the foreign matter removing body 15. Therefore, when the power transmission coil 11 is not used, the foreign matter removing body 15 is operated so that the cover 31 is closed, thereby reducing the possibility that foreign matter is placed on the upper surface of the planar coil 13 when not used. Furthermore, since the foreign matter placed on the upper surface of the cover 31 when the power transmission coil 11 is not used opens the cover 31 when the power transmission coil 11 is used, the foreign matter can be moved away from the upper surface of the planar coil 13 together with the cover 31. It becomes. From these things, it is possible to reduce the possibility that foreign matter is placed on the planar coil 13 with a simple configuration, and the placed foreign matter can be removed from the planar coil 13 by the opening operation of the cover 31. It becomes possible.

  Hereinafter, a detailed configuration in the seventh embodiment will be described with reference to FIG. In FIG. 8, the same components as those in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

  In FIG. 8, a characteristic configuration is that a cover 31 operable along the upper surface of the planar coil 13 is attached to the foreign matter removing body 15. For example, the cover 31 is installed so as to be flush with the floor surface, and the guide rail 25 is embedded in the floor. The planar coil 13 is installed at a position one step below the floor surface. By adopting such a configuration, when the cover 31 is closed, the power transmission coil 11 has almost no step with the floor surface. For this reason, the cover 31 includes a material (for example, reinforced plastic or metal) or a structure (for example, a beam structure) having a strength that does not break even when a heavy object such as a vehicle is placed on the upper surface thereof.

  Note that the control for causing the power control circuit 19 to operate the foreign substance removing body 15 is the same as in the first and second embodiments. Therefore, the power control circuit 19 controls the foreign matter removing body 15 to reach the right end in FIG. 8 when the use of the power transmission coil 11 is finished. As a result, the foreign matter removing body 15 moves in the direction of the arrow in FIG. 8, and the foreign matter placed on the upper surface of the planar coil 13 is removed by the brush 21, and the cover 31 covers the upper surface of the planar coil 13. As a result, foreign matter on the planar coil 13 can be removed, and the possibility of placing foreign matter on the planar coil 13 when the power transmission coil 11 is not used can be reduced.

  When the power transmission coil 11 is used again, the power control circuit 19 controls the foreign matter removing body 15 to move from the right side to the left side in FIG. Thereby, the foreign matter removing body 15 removes fine foreign matters placed on the planar coil 13 from the gap between the floor surface and the cover 31 with the brush 21. When the power transmission coil 11 is not used, the foreign matter placed on the upper surface of the cover 31 moves away from the planar coil 13 together with the cover 31 when the cover 31 is opened. Therefore, before the power transmission coil 11 is used, the fine foreign matter and the foreign matter placed on the cover 31 are removed.

  With the above configuration and operation, it is possible to realize the power transmission coil 11 that can remove foreign matters more reliably with a simple configuration without using a power source such as a dedicated motor for opening and closing the cover 31.

  In the seventh embodiment, the foreign substance removing body 15 is provided with the brush 21. However, the present invention is not limited to this, and as described in the first embodiment, for example, a squeegee may be used. When the power transmission coil 11 is installed in an environment where fine foreign matter entering from the gap between the floor surface and the cover 31 is not generated, the brush 21 may not be provided.

  Further, the power transmission coil 11 of the seventh embodiment may be configured to be provided with the groove 29 described in the sixth embodiment.

  In the seventh embodiment, the power transmission coil 11 is embedded in the floor, but this may be installed on the floor. In this case, although the power transmission coil 11 has a level difference with respect to the floor surface, the installation becomes easy.

  Moreover, although Embodiment 1-7 demonstrated the planar coil 13 as a power transmission side (primary side) coil, this may be a power receiving side (secondary side) coil. In this case, the same effect as in the first to seventh embodiments can be obtained.

  Since the power transmission coil according to the present invention can remove foreign matter with a simple configuration, it is particularly useful as a power transmission coil for non-contact power feeding.

DESCRIPTION OF SYMBOLS 11 Power transmission coil 13 Planar coil 15 Foreign material removal body 17 Magnet 19 Power control circuit 21 Brush 28 Position detection part 29 Groove 31 Cover

Claims (10)

A planar coil;
A foreign matter removing body provided on the upper surface side of the planar coil and operable along the upper surface of the planar coil;
A magnet attached to a position passing through the projection surface of the planar coil in the foreign matter removing body when the foreign matter removing body operates;
A power control circuit electrically connected to the planar coil,
The power control circuit controls the current supplied to the planar coil so that the magnet moves along the upper surface of the planar coil at least before starting power transmission by the planar coil, thereby removing the foreign matter. A power transmission coil designed to operate the body. When the power control circuit moves the magnet along the upper surface of the planar coil, the magnet does not reach the central portion of the planar coil from the operation start position. 2. The power transmission coil according to claim 1, wherein the current is supplied to the planar coil from the time when the planar coil is passed through to the operation end position. When the power control circuit moves the magnet along the upper surface of the planar coil, the magnet supplies the current to the planar coil from the operation start position to the central portion of the planar coil. The absolute value of is controlled so that it gradually decreases from the initial current value,
2. The control according to claim 1, wherein the magnet is controlled so that an absolute value of the current supplied to the planar coil gradually increases to a final current value from a central portion of the planar coil to an operation end position. Power transmission coil. The power control circuit supplies a predetermined current to the planar coil a predetermined number of times by switching between positive and negative before supplying the current for moving the magnet along the upper surface of the planar coil to the planar coil. The power transmission coil according to claim 1. A position detection unit for the foreign substance removal body, which is electrically connected to the power control circuit;
The power control circuit controls the current to be supplied to the planar coil based on the position of the foreign substance removal body detected by the position detection unit when moving the magnet along the upper surface of the planar coil. The power transmission coil according to claim 1. A position detection unit for the foreign substance removal body, which is electrically connected to the power control circuit;
The power control circuit is configured such that the relationship between the position of the foreign matter removing body detected by the position detection unit and the elapsed time from the start of operation of the foreign matter removing body is a predetermined relationship during normal operation of the foreign matter removing body. 2, the power transmission coil according to claim 1, wherein the operation of the foreign matter removing body is determined to be abnormal and the supply of the current to the planar coil is stopped. A portion of the foreign matter removing body that is in contact with the upper surface of the planar coil is constituted by a brush,
The power transmission coil according to claim 1, wherein a groove is provided on an upper surface of the planar coil substantially in parallel with an operation direction of the foreign matter removing body. The power transmission coil according to claim 1, wherein a cover that is operable along an upper surface of the planar coil is attached to the foreign matter removing body. The power transmission coil according to claim 1, wherein the power control circuit operates the foreign matter removing body when power transmission is not performed. The power transmission coil according to claim 1, wherein the magnet is an electromagnet.

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