Power transmission device and power reception device
First Claim
1. A power transmission device that transmits electric power to a power reception device, the power transmission device comprising:
- a power transmission coil configured to transmit electric power to a power reception coil of the power reception device in a contactless manner; and
a foreign object detector provided above the power transmission coil, with the power transmission coil being configured to transmit the electric power to the power reception coil located above the power transmission coil,the foreign object detector includinga plurality of first coils arranged along an upper surface of the power transmission coil, anda plurality of second coils arranged along the upper surface of the power transmission coil above or below the plurality of first coils, the plurality of second coils being provided to correspond to the plurality of first coils,the plurality of second coils each being arranged to face a corresponding one of the first coils, andan outer shape of each of the plurality of first coils and of each of the plurality of second coils being smaller than an outer shape of the power transmission coil when the power transmission coil, the plurality of first coils and the plurality of second coils are viewed two-dimensionally from above the power transmission coil, whereinthe foreign object detector further includes a switching device configured to switch among pairs of coils, the pairs each including one of the plurality of first coils to which an AC voltage for detection is applied and one of the second coils corresponding to the first coil to which the AC voltage for detection is applied, andthe power transmission device further comprises a control device controlling the switching device so as to successively switch among the pairs each including the first coil to which the AC voltage for detection is applied and the second coil corresponding to the first coil to which the AC voltage for detection is applied, the control device determining presence or absence of a foreign object based on a power receiving state of the second coil corresponding to the first coil to which the AC voltage for detection is applied.
2 Assignments
0 Petitions
Accused Products
Abstract
A foreign object detector includes a plurality of first coils and a plurality of second coils. The plurality of first coils are arranged along an upper surface of a power transmission coil. The plurality of second coils are provided to correspond to the plurality of first coils, with the second coils each being arranged to face a corresponding one of the first coils. An outer shape of each of the plurality of first coils and each of the plurality of second coils is smaller than an outer shape of the power transmission coil when the power transmission coil is viewed two-dimensionally from above the power transmission coil.
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Citations
10 Claims
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1. A power transmission device that transmits electric power to a power reception device, the power transmission device comprising:
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a power transmission coil configured to transmit electric power to a power reception coil of the power reception device in a contactless manner; and a foreign object detector provided above the power transmission coil, with the power transmission coil being configured to transmit the electric power to the power reception coil located above the power transmission coil, the foreign object detector including a plurality of first coils arranged along an upper surface of the power transmission coil, and a plurality of second coils arranged along the upper surface of the power transmission coil above or below the plurality of first coils, the plurality of second coils being provided to correspond to the plurality of first coils, the plurality of second coils each being arranged to face a corresponding one of the first coils, and an outer shape of each of the plurality of first coils and of each of the plurality of second coils being smaller than an outer shape of the power transmission coil when the power transmission coil, the plurality of first coils and the plurality of second coils are viewed two-dimensionally from above the power transmission coil, wherein the foreign object detector further includes a switching device configured to switch among pairs of coils, the pairs each including one of the plurality of first coils to which an AC voltage for detection is applied and one of the second coils corresponding to the first coil to which the AC voltage for detection is applied, and the power transmission device further comprises a control device controlling the switching device so as to successively switch among the pairs each including the first coil to which the AC voltage for detection is applied and the second coil corresponding to the first coil to which the AC voltage for detection is applied, the control device determining presence or absence of a foreign object based on a power receiving state of the second coil corresponding to the first coil to which the AC voltage for detection is applied. - View Dependent Claims (2, 3, 4, 5)
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6. A power reception device that receives electric power output from a power transmission device, the power reception device comprising:
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a power reception coil configured to receive electric power from a power transmission coil of the power transmission device in a contactless manner; and a foreign object detector provided below the power reception coil, with the power reception coil being configured to receive the electric power from the power transmission coil located below the power reception coil, the foreign object detector including a plurality of first coils arranged along a lower surface of the power reception coil, and a plurality of second coils arranged along the lower surface of the power reception coil above or below the plurality of first coils, the plurality of second coils being provided to correspond to the plurality of first coils, the plurality of second coils each being arranged to face a corresponding one of the first coils, and an outer shape of each of the plurality of first coils and of each of the plurality of second coils being smaller than an outer shape of the power reception coil when the power reception coil, the plurality of first coils and the plurality of second coils are viewed two-dimensionally from below the power reception coil, wherein the foreign object detector further includes a switching device configured to switch among pairs of coils, the pairs each including one of the plurality of first coils to which an AC voltage for detection is applied and one of the second coils corresponding to the first coil to which the AC voltage for detection is applied, and the power reception device further comprises a control device controlling the switching device so as to successively switch among the pairs each including the first coil to which the AC voltage for detection is applied and the second coil corresponding to the first coil to which the AC voltage for detection is applied, the control device determining presence or absence of a foreign object based on a power receiving state of the second coil corresponding to the first coil to which the AC voltage for detection is applied. - View Dependent Claims (7, 8, 9, 10)
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Specification