Tdk Corporation

Kazuyoshi Hanabusa

Takashi Urano

Masayuki Kobayashi

Takeshi Kamono

Kouichi Sakita

Katsunori Imai

Hironobu Masuoka

Masayuki Yamashima

Kazuki Yoneda

Ryo Shiozaki

Satoshi Miyagi

Osamu Kobayashi

A wireless power receiving device that receives AC power from a power transmission coil included in a wireless power transmission device. The wireless power receiving device includes a power receiving coil configured to receive AC power from a power transmission coil, a power receiving-side imaging unit having an auto-focus function, and a control unit configured to cause the power receiving-side imaging unit to image a range able to be imaged by the power receiving-side imaging unit and, in a case in which a marker located at a predetermined first position on an outer surface of the wireless power transmission device is imaged by the power receiving-side imaging unit, to output relative distance information representing relative distance of the power receiving coil with respect to the power transmission coil based on a detected distance using the auto-focus function used by the power receiving-side imaging unit for imaging the marker.

Wireless power receiving device, wireless power transmission device, and wireless power transmission system

A wireless power transmission device capable of reducing an output power of wireless power receiving device receiving power transmitted from a wireless power transmission device. The wireless power transmission device including: a DC (Direct Current)/DC converter; an inverter configured to convert output voltage of the DC/DC converter into AC voltage having driving frequency; a power transmission coil configured for the AC voltage to be supplied to from the inverter and configured to generate the AC magnetic field; a transmission-side resonance circuit including the power transmission coil; and control circuit configured to increase difference between a driving frequency of the inverter and a resonance frequency of the transmission-side resonance circuit when a predetermined condition is satisfied.

Wireless power transmission device and wireless power transmission system

A power transmission device which can increase a frequency change width (frequency dispersion region) while curbing output fluctuations. The power transmission device that wirelessly transmits power to a power receiving device includes an inverter configured to convert a voltage into an alternating current voltage with a drive frequency, a power supply configured to generate the voltage to be supplied to the inverter, a power transmission coil configured to be supplied with the alternating current voltage and generate an alternating current magnetic field, and a voltage changing unit configured to spontaneously change an output voltage of the power supply, wherein the inverter is configured to control the drive frequency in response to a change in the output voltage.

Power transmission device and wireless power transmission system

A power feeding device which wirelessly transmits power towards a power receiving device equipped with a power receiving coil device, comprising: a magnetic structure having two magnetic bodies; and a power feeding coil device which receives power from a power supply and generates an alternating magnetic field, the mutual main surfaces of the two magnetic bodies face each other, and the two magnetic bodies are disposed to be separated at a predetermined distance, the power feeding coil device is disposed at any position between the two magnetic bodies, the two magnetic bodies receive the alternating magnetic field during power transmission, and a power feeding region in which transmitting power towards the power receiving coil device is possible is formed between the two magnetic bodies.

Power feeding device and wireless power transmission device

Disclosed herein is a magnetic coupling device that includes first and second coil units that transmit power or signals with each other by wireless. Each of the first and second coil units includes a first coil and a second coil. The first coil of the first coil unit and the first coil of the second coil unit are magnetically coupled to each other. The second coil of the first coil unit and the second coil of the second coil unit are magnetically coupled to each other. At least one of the first and second coil units has an electromagnetic shielding member disposed at a position preventing magnetic coupling between the first and second coils.

Magnetic coupling device and wireless power transmission system using the same

Disclosed herein is a rotary type magnetic coupling device used for a rotator. The rotary type magnetic coupling device includes first and second coils magnetically coupled to each other, and third and fourth coils magnetically coupled to each other. The coil axes of the first and second coils extend in a rotary axis direction of the rotator, and the coil axes of the third and fourth coils radially extend in a radial direction substantially orthogonal to the rotary axis of the rotator.

Rotary type magnetic coupling device

Disclosed herein is a magnetic coupling device that includes first and second coil units that transmit power or signals with each other by wireless. Each of the first and second coil units includes a first coil and a second coil. At least one of the first and second coil units has a first magnetic body constituting a magnetic path of a first magnetic flux interlinking the first coil and a second magnetic body constituting a magnetic path of a second magnetic flux interlinking the second coil. A permeability of the first magnetic body is larger than a permeability of the second magnetic body at a driving frequency of the first coil and smaller than a permeability of the second magnetic body at a driving frequency of the second coil higher than the driving frequency of the first coil.

Disclosed herein is a wireless power transmitting device that includes: a boost converter boosting an input DC voltage; an inverter converting an output voltage of the boost converter into an AC voltage; a power transmitting coil supplied with the AC voltage to generate an AC magnetic field; a receiving circuit receiving a power transmission command signal; a boost control circuit controlling a boost level of the boost converter according to the power transmission command signal; an operation detection circuit detecting whether or not the boost converter is operated; and an inverter control circuit controlling the inverter. The operation detection circuit activates a stop signal when detecting that the boost converter does not perform operation after an elapse of a predetermined time period from a start of power transmission. The inverter control circuit stops an operation of the inverter in response to the stop signal.

Wireless power transmitting device and wireless power transmission system using the same

Disclosed herein is a wireless power transmission device includes a power transmitting transformer coupled between a power transmitting circuit and a power receiving circuit, and a signal transmitting transformer coupled between a signal generating circuit provided at the power receiving circuit side and a control circuit provided at the power transmitting circuit side. The frequency of an AC signal transmitted by the signal transmitting transformer is equal to or more than ten times the frequency of an AC voltage transmitted by the power transmitting transformer. The signal generating circuit converts the magnitude of the output voltage or output current of the power receiving circuit into a magnitude of an amplitude of the AC signal.

Wireless power transmission device

Disclosed herein is a rotary type magnetic coupling device including first and second coils magnetically coupled to each other used for a rotator. Each of the first and second coils is a loop-shaped having an opening surrounding a rotary axis of the rotator. Each of the first and second coils includes first and second wiring parts extending in a peripheral direction of the rotator, a third wiring part bent in the rotary axis direction from one end of the first and second wiring parts, and a fourth wiring part bent in the rotary axis direction from other end of the first and second wiring parts. At least one of the first and second coils is configured such that the third and fourth wiring parts match or overlap each other when viewed in a radial direction substantially orthogonal to the rotary axis.

A power transmission device, which is used for a contactless power transmission to a movable body moving on a travelling surface in a power transmission direction parallel to the travelling surface, including a power transmission coil and a shielding plate, wherein, the power transmission coil is installed so that a coil surface is approximately vertical to the travelling surface, and at least a part of the shielding plate is disposed inside the region on the travelling surface sandwiched between a plane surface defined by a coil surface of the power transmission coil and a plane surface defined by a coil surface of a power receiving coil mounted on the movable body.

Power transmission device

A switching power supply capable of executing output voltage stabilizing control with a high degree of reliability even when the DC output voltage is at DC 2V or lower. A DC--DC converter unit 1 converts a DC input voltage Vin to DC through switching and outputs a DC output voltage Vo for a load 10 through output lines 71 and 72. An auxiliary power unit 3, which is electrically linked to the DC--DC converter unit 1, outputs a DC voltage Va through an auxiliary source output line 30 having a potential that is negative relative to the potential at the lower-potential output line 72. An output voltage detection unit 2, connected between the higher-potential output line 71 and the auxiliary source output line 30, detects a DC voltage (Vo+Va) manifesting between them and provides the detection signal to a control unit 4 via a photocoupler 9. The control unit 4 implements output voltage stabilizing control on the DC--DC converter unit 1.

Switching power supply

A coil assembly having a drum core for winding a coil wire. The drum core has a drum portion and a pair of end flanges provided at the opposite ends of the drum portion. The wire is wound on the drum portion. The drum core is encircled by a cylindrical ring core. The drum core and the ring core are supported by a base plate which has a recess for receiving end portions of the drum core and the ring core for appropriately locating the drum core and the ring core during assembling. The ring core is formed with cutouts leaving projecting edges at the end adjacent to the base plate. The base plate is provided with terminals at the edge portions adjacent to the cutouts of the ring core. End portions of the coil wire are passed through the cutouts and connected with the terminals.

Growing community of inventors

Tokyo, Japan

Kazuyoshi Hanabusa