Honda Motor Co., Ltd.

Mizuho Doi

Koji Kobayashi

Tomohiro Hoshi

Nobuhiko Yoshimoto

Yuichi Fukuda

Yasuo Shimizu

Shunichiro Sueyoshi

Yoshito Nakamura

Hitoshi Harata

Hitoshi Harada

Yukiya Kashimura

Hitoshi Karasawa

A plating apparatus includes a plating tank for storing a plating liquid, and applies a magnetic alloy plating to a shaft-shaped member immersed in the plating liquid by using the shaft-shaped member as a cathode. The plating apparatus further includes a rotable member configured to rotate the shaft-shaped member as a rotary shaft; annular shielding tools mounted on the outer peripheral surface of the shaft-shaped member; a plating liquid discharge nozzle including plating liquid discharge ports which are provided to face the shaft-shaped member so as to avoid the shielding tools; and an anode provided around the shaft-shaped member and the plating liquid discharge nozzle.

Plating apparatus

This magnetostrictive torque sensorincludes a rotating shaftused to rotate according to an input torque and provided with magnetostrictive filmsA andB, an excitation coilconfigured to apply an alternating magnetic fieldto the magnetostrictive film, and detection coilsA andB each of which detects a change in the magnetic characteristic of an associated one of the magnetostrictive films. The magnetostrictive torque sensor is configured so that a bias magnetic field is added to the alternating magnetic field from a bias power supplyso as to satisfy the following conditions:H&#x3c;H&#x3c;H; and&#x2212;where H(&#x3e;0) is an applied magnetic field corresponding to a maximum magnetic permeability obtained according to a magnetic hysteresis curveof the magnetostrictive film, which shows magnetization caused by the alternating magnetic field, H(&#x3e;0) is an applied magnetic field corresponding to an end of a range in which a discontinuous magnetization is performed, and H(&#x3e;0) is an applied magnetic field that determines a sensitivity range to be set on a magnetostrictive sensitivity curve representing a magnetostrictive sensitivity exhibited by the magnetostrictive film.

Magnetostrictive torque sensor and electric power steering apparatus

For forming an annular magnetostrictive coat on an outer peripheral surface of a rotational shaft associated with a magnetostrictive torque sensor, a magnetostrictive-coat forming method comprises a step of fitting a cylindrical masking jig over the outer peripheral surface of the rotational shaft and securing the masking jig to the outer peripheral surface, a step of placing the rotational shaft in a plating tank to thereby form the magnetostrictive coat by plating on the outer peripheral surface, and a step of detaching the masking jig from the rotational shaft.

Magnetostrictive coat forming method, magnetostrictive torque sensor manufacturing method, and electric power steering apparatus employing the sensor

A magnetostrictive torque sensor comprising a first magnetostrictive film, a second magnetostrictive film, and a third magnetostrictive film formed over the entire circumferential periphery of a surface of a rotating shaft. A first sensor coil, a second sensor coil, and a third sensor coil for sensing changes in impedance are provided for the first, second, and third magnetostrictive films, respectively. Signals according to the changes in impedance outputted from the first through third sensor coils are inputted to a torque calculating unit. The torque calculating unit calculates the torque applied to the rotating shaft on the basis of the output signal from the first sensor coil and the output signal from the second sensor coil. Furthermore, the output signals from the first through third sensor coils are compared, and failures in the first magnetostrictive film or the second magnetostrictive film are detected by a failure detector.

Magnetostrictive torque sensor and electrically powered steering apparatus using same

For forming an annular magnetostrictive coat on an outer peripheral surface of a rotational shaft associated with a magnetostrictive torque sensor, a magnetostrictive coat forming method comprises a step of fitting a cylindrical masking jig over the outer peripheral surface of the rotational shaft and securing the masking jig to the outer peripheral surface, a step of placing the rotational shaft in a plating tank to thereby form the magnetostrictive coat by plating on the outer peripheral surface, and a step of detaching the masking jig from the rotational shaft.

Growing community of inventors

Sayama, Japan

Mizuho Doi