Abstract: An electric power transmission device capable of efficiently performing contactless electric power transmission to an underwater vehicle in water is provided. The electric power transmission device, which is an electric power transmission device transmitting electric power to an electric power reception device including an electric power reception coil in water, includes one or more transmission coils including an electric power transmission coil which transmits electric power to an electric power reception coil via a magnetic field, an electric power transmission unit which transmits AC power to an electric power transmission coil, a capacitor which is connected to the transmission coil and forms a resonant circuit which resonates with the transmission coil, and a buoyant body connected to at least one of the transmission coils.

Abstract: A power transmission device transmits power underwater to a power reception device including a power reception coil. The power transmission device includes: a power transmission coil that transmits power to the power reception coil through a magnetic field; a power transmitter that transmits an alternating current power having a predetermined frequency to the power transmission coil; and a first capacitor that is connected to the power transmission coil and forms a resonance circuit resonating with the power transmission coil. The predetermined frequency is a frequency between a first frequency at which a geometric mean value of a Q value of the power transmission coil and a Q value of the power reception coil are the maximum and a second frequency at which the Q value of the power transmission coil and the Q value of the power reception coil are the same.

Abstract: A power transmission device is configured to transmit power underwater to an underwater vehicle having a power reception coil. The power transmission device includes a power transmission coil configured to transmit power to the power reception coil through a magnetic field, a power transmission unit configured to transmit an alternating current voltage having a frequency a 10 kHz or lower to the power transmission coil, and a first capacitor connected to the power transmission coil and configured to form a resonance circuit resonating at the frequency with the power transmission coil.

Abstract: An electric power transmission device capable of efficiently performing contactless electric power transmission to an underwater vehicle in water is provided. The electric power transmission device, which is an electric power transmission device transmitting electric power to an electric power reception device including an electric power reception coil in water, includes one or more transmission coils including an electric power transmission coil which transmits electric power to an electric power reception coil via a magnetic field, an electric power transmission unit which transmits AC power to an electric power transmission coil, a capacitor which is connected to the transmission coil and forms a resonant circuit which resonates with the transmission coil, and a buoyant body connected to at least one of the transmission coils.

Abstract: A power transmission device transmits power underwater to a power reception device including a power reception coil. The power transmission device includes: a power transmission coil that transmits power to the power reception coil through a magnetic field; a power transmitter that transmits an alternating current power having a predetermined frequency to the power transmission coil; and a first capacitor that is connected to the power transmission coil and forms a resonance circuit resonating with the power transmission coil. The predetermined frequency is a frequency between a first frequency at which a geometric mean value of a Q value of the power transmission coil and a Q value of the power reception coil are the maximum and a second frequency at which the Q value of the power transmission coil and the Q value of the power reception coil are the same.

Abstract: A power transmission device is configured to transmit power underwater to an underwater vehicle having a power reception coil. The power transmission device includes a power transmission coil configured to transmit power to the power reception coil through a magnetic field, a power transmission unit configured to transmit an alternating current voltage having a frequency a 10 kHz or lower to the power transmission coil, and a first capacitor connected to the power transmission coil and configured to form a resonance circuit resonating at the frequency with the power transmission coil.

Abstract: An imaging device has a bearing that has a first ring and a second ring, a first plate that is disposed on one side of the bearing and fixed to the first ring, an imaging unit that is disposed on a side of the first plate, a second plate that is disposed on another side of the bearing and fixed to the second ring, a first inductor that is accommodated in the first plate, and a second inductor that faces the first inductor and is accommodated in the second plate.

Abstract: An imaging device has a bearing that has a first ring and a second ring, a first plate that is disposed on one side of the bearing and fixed to the first ring, an imaging unit that is disposed on a side of the first plate, a second plate that is disposed on another side of the bearing and fixed to the second ring, a first inductor that is accommodated in the first plate, and a second inductor that faces the first inductor and is accommodated in the second plate.

Abstract: Reduction in the power transmission efficiency due to imprecise positioning between a primary power transmission coil and a secondary power reception coil is avoided. For transmitting electric power in a wireless manner to an electronic device including a secondary power reception coil and configured to receive electric power via the secondary power reception coil, a power transmission device includes a primary power transmission coil and a power transmission circuit unit for supplying electric power to the primary power transmission coil, and a transmission circuit unit is formed by the primary power transmission coil and the secondary power reception coil. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling coefficient between the primary power transmission coil and the secondary power reception coil.

Abstract: Provided is a contactless electric power feeding system that allows a plurality of devices to be recharged at the same time. A feeding device includes a primary feeding coil and each receiving device includes a secondary receiving coil. Each coil forms a resonance circuit jointly with a capacitor, and the two resonance circuits are electro-magnetically coupled with each other to from a transmission circuit unit. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling efficient between the primary feeding coil and the secondary receiving coil, and the output impedance of a power supply unit for supplying electric power to the primary feeding coil is smaller than the first impedance.

Abstract: Reduction in the power transmission efficiency due to imprecise positioning between a primary power transmission coil and a secondary power reception coil is avoided. For transmitting electric power in a wireless manner to an electronic device including a secondary power reception coil and configured to receive electric power via the secondary power reception coil, a power transmission device includes a primary power transmission coil and a power transmission circuit unit for supplying electric power to the primary power transmission coil, and a transmission circuit unit is formed by the primary power transmission coil and the secondary power reception coil. A first impedance of an input end of the transmission circuit unit is matched with a second impedance of an output end of the transmission circuit unit by using a coupling coefficient between the primary power transmission coil and the secondary power reception coil.

Abstract: A transmission/reception antenna and a transmission/reception device using the antenna wherein the antenna includes a dielectric base board, an excitation loop antenna provided on the dielectric base board, a transmission/reception loop antenna provided on the dielectric base board in close proximity of but not in contact with the excitation loop antenna, and a resonance capacitor connected between two ends of the transmission/reception loop antenna. A coupling capacitor is connected to one of the two ends of the transmission/reception loop antenna. The excitation loop antenna is connected to a transmitter, and the transmission/reception loop antenna is connected to the receptor via the coupling capacitor. Thereby, the frequency property may be expanded without increasing the power consumption, and the reception processing unit is enabled to properly process the reception signal.

Abstract: Provided are a transmission/reception antenna and a transmission/reception device using the same wherein the transmission/reception antenna comprises an excitation loop antenna (12) having a loop of a single turn and a transmission/reception loop antenna (14) having a pair of loops (14a, 14b) of a plurality of turns which are closely wound around a magnetic member (11). The two loops of the transmission/reception loop antenna are located on either side of the excitation loop. A resonance capacitor (15) is connected across one ends of the two loops of the transmission/reception loop antenna, and a connecting portion (14c) is connected between the ends of the two loops opposite to those connected to the resonance capacitor. The frequency property is expanded without increasing the power consumption.

Abstract: The present invention is concerned with a transmitting/receiving antenna, which includes a dielectric board, a driven loop antenna provided to the dielectric board, transmit processing portion connection terminals connected to the driven loop antenna, a transmitting/receiving loop antenna arranged in close vicinity to the driven loop antenna in a non-contact state, a resonance capacitor connected to both ends of the transmitting/receiving loop antenna, and receive processing portion connection terminals connected to the transmitting/receiving loop antenna. The driven loop antenna is constructed to have a loop wound in a single turn, and the transmitting/receiving loop antenna is constructed to have a loop wound in plural turns. According to this configuration, a wider frequency band of the frequency characteristic and a reduction of the power consumption can be achieved.

Abstract: Provided are a transmission/reception antenna and a transmission/reception device using the same wherein the transmission/reception antenna comprises a dielectric base board (11), an excitation loop antenna (12) provided on the dielectric base board, a transmission/reception loop antenna (13) provided on the dielectric base board in close proximity of but not in contact with the excitation loop antenna, and a resonance capacitor (14) connected between two ends of the transmission/reception loop antenna. A coupling capacitor (19) is connected to one of the two ends of the transmission/reception loop antenna. The excitation loop antenna is connected to a transmission processing unit, and the transmission/reception loop antenna is connected to the reception processing unit via the coupling capacitor. Thereby, the frequency property may be expanded without increasing the power consumption, and the reception processing unit is enabled to properly process the reception signal.

Abstract: Provided are a transmission/reception antenna and a transmission/reception device using the same wherein the transmission/reception antenna comprises an excitation loop antenna (12) having a loop of a single turn and a transmission/reception loop antenna (14) having a pair of loops (14a, 14b) of a plurality of turns which are closely wound around a magnetic member (11). The two loops of the transmission/reception loop antenna are located on either side of the excitation loop. A resonance capacitor (15) is connected across one ends of the two loops of the transmission/reception loop antenna, and a connecting portion (14c) is connected between the ends of the two loops opposite to those connected to the resonance capacitor. The frequency property is expanded without increasing the power consumption.

Abstract: The present invention is concerned with a transmitting/receiving antenna, which includes a dielectric board, a driven loop antenna provided to the dielectric board, transmit processing portion connection terminals connected to the driven loop antenna, a transmitting/receiving loop antenna arranged in close vicinity to the driven loop antenna in a non-contact state, a resonance capacitor connected to both ends of the transmitting/receiving loop antenna, and receive processing portion connection terminals connected to the transmitting/receiving loop antenna. The driven loop antenna is constructed to have a loop wound in a single turn, and the transmitting/receiving loop antenna is constructed to have a loop wound in plural turns. According to this configuration, a wider frequency band of the frequency characteristic and a reduction of the power consumption can be achieved.

Abstract: An antenna device includes: a substrate; first and a second antenna units which are wound coaxially on a surface of the substrate, and include a plurality of antenna elements; and a feeder which feeds power only to the first antenna unit. A separation distance between the antenna elements in each of the first and second antenna units is substantially the same.