Seiko Instruments Inc

Kou Yamazaki

Keishi Honmura

Nobuo Tsukada

A wristwatch with an oscillation alarm uses an ultrasonic motor as its drive source. A vibration member has a piezoelectric element adhered thereto on one side and comb-like projections on the other side. A rotor has a sliding member composed of resin at its contacting portion with the comb-like projections and an eccentric weight at its outer circumferential portion. Shock absorbers are sandwiched between the weight and the rotor to absorb shocks applied to the rotor and thus prevent rotor damage. In the vicinity of the upper or lower side of the weight, there is disposed an abutment portion made of rigid material, the abutment portion abutting with the weight when shocks of large magnitude are applied to the rotor to assist the shock absorbers in preventing damage to the rotor.

Growing community of inventors

Tokyo, Japan

Kou Yamazaki