Abstract: A power transmission device for a noncontact power supply device includes a resonant circuit that outputs an alternating magnetic flux by power from a power source circuit, and switching elements for making the resonant circuit generate an alternating magnetic flux, and transmits power to a power receiving coil of a power reception device by the alternating magnetic flux. A power transmission controller of the power transmission device includes a transmission mode of supplying alternating power to the resonant circuit by repeating ON and OFF of switching elements by controlling switching elements. ON time in one cycle of operation of each of switching elements used in the transmission mode is a first fixed value. Accordingly, the power transmission device in a simplified configuration can be provided.

Abstract: A control device for a noncontact power supply device includes a power transmission coil for outputting an alternating magnetic flux upon receiving alternating electric power, and a power transmission control unit for controlling alternating electric power to be supplied to the power transmission coil. The power transmission control unit includes a first mode and a second mode. The first mode controls the alternating electric power to be supplied to the power transmission coil in order to transmit electric power, to be supplied to a load of a power reception device, to a power reception coil, and the second mode controls the alternating electric power for supplying electric power less than the electric power transmitted by the first mode to the power transmission coil. After being activated, the power transmission control unit selects initially the first mode.

Abstract: A noncontact power supply device includes a power transmission device, a magnetism collecting device, and a power reception device. The power transmission device includes switching elements that make a power-transmission resonant circuit generate an alternating magnetic flux from a power source circuit. The power reception device includes a magnetism collecting device having a magnetism collecting circuit not connected to a load, a power receiving coil which is capable of being magnetically coupled to the magnetism collecting device, and a rectifier circuit that supplies output power of the power receiving coil to a load. A power-transmission resonance frequency of the power-transmission resonant circuit is smaller than a drive frequency of each of switching elements, and a power-reception resonance frequency of the magnetism collecting circuit is larger than the drive frequency of each of switching elements.

Abstract: A noncontact power supply device includes a power transmission device, a magnetism collecting device, and a power reception device. The power transmission device includes switching elements that make a power-transmission resonant circuit generate an alternating magnetic flux from a power source circuit. The power reception device includes a magnetism collecting device having a magnetism collecting circuit not connected to a load, a power receiving coil which is capable of being magnetically coupled to the magnetism collecting device, and a rectifier circuit that supplies output power of the power receiving coil to a load. A power-transmission resonance frequency of the power-transmission resonant circuit is smaller than a drive frequency of each of switching elements, and a power-reception resonance frequency of the magnetism collecting circuit is larger than the drive frequency of each of switching elements.

Abstract: A control device for a noncontact power supply device includes a power transmission coil for outputting an alternating magnetic flux upon receiving alternating electric power, and a power transmission control unit for controlling alternating electric power to be supplied to the power transmission coil. The power transmission control unit includes a first mode and a second mode. The first mode controls the alternating electric power to be supplied to the power transmission coil in order to transmit electric power, to be supplied to a load of a power reception device, to a power reception coil, and the second mode controls the alternating electric power for supplying electric power less than the electric power transmitted by the first mode to the power transmission coil. After being activated, the power transmission control unit selects initially the first mode.

Abstract: A power transmission device for a noncontact power supply device includes a resonant circuit that outputs an alternating magnetic flux by power from a power source circuit, and switching elements for making the resonant circuit generate an alternating magnetic flux, and transmits power to a power receiving coil of a power reception device by the alternating magnetic flux. A power transmission controller of the power transmission device includes a transmission mode of supplying alternating power to the resonant circuit by repeating ON and OFF of switching elements by controlling switching elements. ON time in one cycle of operation of each of switching elements used in the transmission mode is a first fixed value. Accordingly, the power transmission device in a simplified configuration can be provided.

Abstract: Power reception device includes a plurality of secondary coils which interlinks with magnetic flux output by primary coil and at least one power reception side capacitor electrically connected to the plurality of secondary coils, and receives power without contact from power transmission device including primary coil. The plurality of secondary coils are connected in series to each other. Central axes of the plurality of secondary coils are oriented in mutually different directions. The plurality of secondary coils and power reception side capacitors configure one power reception side resonance circuit. According to the present aspect, power reception side resonance circuit can be easily designed, and a decrease of power transmission efficiency can be suppressed.

Abstract: A contactless power transmission device is provided with: a washstand that includes a primary coil; and an electric toothbrush that includes a secondary coil, a rectifier circuit, and a feed control unit. The electric toothbrush includes a first auxiliary coil which relays a magnetic flux which flows from the primary coil to the secondary coil, and a second auxiliary coil which relays a magnetic flux which flows from the primary coil to the secondary coil. A central axis of the second auxiliary coil is perpendicular to a central axis of the first auxiliary coil.

Abstract: A non-contact power transmission device, comprising a washbasin including a primary coil, and an electric toothbrush including a secondary coil. A central door includes a third relay coil that relays the flow of magnetic flux from the primary coil to the secondary coil. The position of the third relay coil relative to the primary coil changes as a result of the opening and closing of the central door.

Abstract: According to a first aspect, a secondary side of contactless power transmission apparatus includes: a holding member which is physically separated from a primary side; a magnetic layer; a shield layer for shielding electromagnetic noise; and a heat insulation layer. The secondary coil is a planar coil and supported by the holding member, and at least the magnetic layer is laminated on one side of the planar coil and unified with the planar coil. According to a second aspect, the secondary side of the apparatus includes a plurality of magnetic layers. Each permeability of the magnetic layers is different from each other, and each of the magnetic layers forms a magnetic path with the primary side.

Abstract: A driving circuit drives a switching element such that an ON-period of the switching element is shorter when a power receiving device is detected not to be placed than when the power receiving device is placed.

Abstract: Power saving is promoted by oscillating only power transmission coil contributing to contactless charging without using any communication means.

Abstract: A non-contact power transmission device includes a resonant circuit, which includes a switching element and a primary coil electrically connected to the switching elements. The resonant circuit induces an alternating power with the primary coil in accordance with the resistance value of the resonant circuit by switching the switching element. A secondary coil receives, from the primary coil in a non-contact manner, the alternating power at a position intersecting an alternating magnetic flux occurring at the primary coil. A primary side controller ON/OFF controls the switching element and changes, based on information to be conveyed to the secondary coil, the resistance value of the resonant circuit, thereby modulating the amplitude of the alternating power induced in the primary coil. A secondary side controller demodulates, from the change in the amplitude of the alternating power received by the secondary coil, the information conveyed to the secondary coil.

Abstract: An electrostatic atomization device provided with a transformer including primary and secondary coils. A switching element is connected in series to the primary coil. A switching element drive circuit provides the switching element with a pulse signal to perform a switching operation and generate high voltage from the secondary coil. A discharge unit including a discharge electrode performs electrostatic atomization on liquid supplied to the discharge electrode to generate charged fine liquid droplets when high voltage generated by the secondary coil is applied to the discharge electrode. The switching element drive circuit generates a pulse signal having an oscillation frequency set so that the transformer has drooping characteristics that prevent air discharge from occurring between the discharge electrode and ground even when load on the discharge unit varies and prevents the generation of ozone having a predetermined concentration or greater when the liquid undergoes electrostatic atomization.

Abstract: A noncontact charger includes a charger having a power transmitting planar coil that transmits high-frequency charging power and a charged device including a power receiving planar coil magnetically coupled to the power transmitting planar coil to receive the charging power, wherein the charger includes a primary authentication planar coil which transmits high-frequency authenticating power for authenticating the charged device and receives a high-frequency authenticating signal for authenticating the charged device, a secondary authentication planar coil is magnetically coupled to the primary authentication planar coil to receive the authenticating power and output the authenticating signal generated from the authenticating power to the primary authentication planar coil, and a space between the power transmitting planar coil and the power receiving planar coil overlaps with a space between the primary authentication planar coil and the secondary authentication planar coil.

Abstract: Disclosed is a discharge device (20) which comprises a power supply unit (22) that supplies a first voltage, a piezoelectric transducer (24) that increases the first voltage to a second voltage by means of vibrations, and a first electrode (26) for producing a discharge product (P) by performing a discharge upon application of the second voltage. The first electrode (26) and the piezoelectric transducer (24) are electrically connected with each other via a vibration damping unit (30). In other words, the first electrode (26) and the piezoelectric transducer (24) are arranged to be out of contact with each other.

Abstract: To provide a power supply circuit which can be applied worldwide without using a high withstand voltage switching element and can supply a load device with stable power. A charging section is arranged between a turn-off capacitor and a load coil. The charging section has the anode connected to the positive terminal of a feedback coil and the cathode connected to the cathode of a zener diode. Thus, when a voltage of a commercial power supply is high, the charging section operates, the turn-off capacitor is quickly charged, an on-period of a transistor is shortened, and an excessive voltage is prevented from being applied between the drain and the source of the transistor. At the same time, an output characteristic indicating relationship between the voltage of the commercial power supply and a current flowing in the load device is permitted to be flat.

Abstract: This invention has an object to a planar coil, a contactless electric power transmission device using the same. This planar coil is configured to suppress an eddy current developed between adjacent turns of wire for minimizing adverse effects on ambient electrical appliances resulting from heat generation. The planar coil 1 in the present invention is formed of spiral shaped wire 7 coated with thinned insulative film, in which adjacent turns of the wire 7 are spaced in radial direction at such a predetermined interval to suppress an eddy current. This planar coil 1 is preferably employed as a power transmission coil or power receiving coil.

Abstract: A self-excited oscillation circuit of the invention includes a turn-OFF transistor that turns OFF a transistor, a turn-OFF capacitor that outputs a voltage to the base of the turn-OFF transistor, and a bias resistance that charges the turn-OFF capacitor with a voltage in magnitude corresponding to a drain current that flows when the transistor turns ON. A resistance is connected between the turn-OFF capacitor and a power supply portion. Accordingly, charges are accumulated in the turn-OFF capacitor so that the voltage will not drop to or below a bias voltage. It thus becomes possible to make the bias resistance smaller, which can in turn reduce an energy loss at the bias resistance.

Abstract: Power saving is promoted by oscillating only power transmission coil contributing to contactless charging without using any communication means.