Patent ID: 7683572
Filing Date: 2010-03-23
Classification: H02J

Abstract:
1. A battery charging cradle and mobile electronic device, wherein the battery charging cradle incorporates a primary coil which is connectable to an AC power source, and the mobile electronic device includes a secondary coil which is operable to be electromagnetically coupled to the primary coil of the battery charging cradle, and further includes a rechargeable battery which is rechargeable by electric power which is induced to the secondary coil; wherein the rechargeable battery has a first flat surface and a second flat surface facing the first flat surface, each of the first flat surface and the second flat surface being rectangular; wherein the battery charging cradle has a planar top plate on an upper side thereof, the mobile electronic device being detachably mountable on the planar top plate; wherein the primary coil is incorporated in the battery charging cradle such that an AC magnetic flux is induced to a specific portion of the top plate; wherein the mobile electronic device has a planar bottom plate to be placed on the top plate of the battery charging cradle, the secondary coil of the mobile electronic device being disposed inside the bottom plate; wherein the secondary coil is a coreless planar coil formed with a wire material spirally wound in a planar manner, the coreless planar coil being provided on the first flat surface of the rechargeable battery so as to be parallel to the first flat surface of the rechargeable battery; wherein a width of the secondary coil is larger than a thickness of the secondary coil, the width extending in a direction parallel to the first flat surface of the rechargeable battery and the thickness being orthogonal to the first flat surface of the rechargeable battery; wherein the battery charging cradle has a positioning portion for arranging the mobile electronic device in a predetermined position, the predetermined position being such that the primary coil is electromagnetically coupled to the secondary coil, and AC power is supplied from the primary coil to the secondary coil, and thus the rechargeable battery incorporated in the mobile electronic device is charged.