Sumitomo Electric Industries, Limited

Toyota Jidosha Kabushiki Kaisha

Hironobu Saka

Yukio Nishizawa

Takeshi Ariyoshi

Naoto Koshino

Shinichi Iizuka

Takashi Hirakushi

Keiji Takizawa

Segment coils arranged as aligned in slot portions of an annular core each include a straight portion and a pair of coil end portions, and have a tip end of the coil end portion of the pair of coil end portions as a tip end portion for joint including a joint surface for joint to another segment coil. The tip end portion for joint has the joint surface in parallel to a radial direction of the annular core when viewed in an axial direction of the annular core.

Segment coil, stator including segment coil, and method of manufacturing segment coil

Each of segment coils arranged as aligned in a slot of a stator core includes a coil central portion accommodated in the slot and two coil end portions protruding outward. The coil end portion of the two coil end portions includes a pair of coil pieces formed by inclining a coil at different angles toward the coil central portion with a vertex lying therebetween. Any one of the pair of coil pieces includes in a region in the vicinity of the vertex, a recessed step portion formed from two sides in non-parallel to and at an angle with respect to an end surface of the stator core.

Segment coil, method of manufacturing segment coil, and stator including segment coil

In order to effectively damp the vibration of the drum of a drum brake, which is a main cause of brake squeals, a vibration detector and a vibrator are provided and operated separately from each other. The vibration damping control is carried out directly mechanically, or in a non-contact manner to improve durability of the device. A piezoelectric element, magnetic sensor or acceleration sensor is used to detect the vibration of the drum. The detected vibration is converted to an electric signal. After adjusting its phase and amplitude, the electric signal is converted to vibration force and outputted through a piezoelectric element or magnetic actuator as the vibrator to suppress brake squeals.

Vibration damper for a drum brake

A vibration damping mechanism for use in a disc brake which can effectively suppress squeaks of the disc brake during braking. Vibrations of the rotor are detected by a piezoelectric element pressed against the back of an inner pad. The detection signal is inputted in a control circuit. The control circuit applies a control signal to another piezoelectric element which produces oscillations having a frequency that can reduce the detection signal to zero. The oscillations produced by the piezoelectric element are transmitted to the rotor to cancel the vibrations of the rotor. With this arrangement, signal components other than the rotor vibrations are scarcely contained in the detection signal, so that it is possible to produce oscillations that can cancel vibrations of the rotor with high accuracy. As a result, the rotor vibrations and thus squeaks of the disc brake are effectively suppressed.

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Osaka, Japan

Hironobu Saka