Seiko Epson Corporation

Shigeyuki Fujimori

Osamu Takahashi

Osamu Shinkawa

Joji Kitahara

Hidenori Nakamura

Kunio Koike

Eisaku Shimizu

Kenichi Okuhara

Kenichi Miyazawa

Imao Hiraga

Yoichi Hayashi

A timepiece display apparatus causes a day hand to move reciprocally by means of center wheel, driven day wheel, cam, lever, and rack. These wheels, cam, lever, and rack can be easily arranged to fit the available space on the main plate of the movement, and the construction of the display apparatus can thus be simplified. Furthermore, locating the cam between the rotary shaft and rack of the lever portion enables arranging a plurality of parts more compactly than if the cam is disposed to a different location, and affords a simple assembly.

Timepiece display apparatus, movement, and timepiece

An electronic timepiece includes a radio wave receiving antenna () for receiving radio waves, electromagnetic motors () for driving a time display part, a battery (), and a body case for receiving the antenna (), electromagnetic motors (), and the battery (). The antenna (), electromagnetic motors (), and the battery () do not overlap as viewed in the viewing direction of a time display part, that is, they do not overlap two-dimensionally. By such a structure, the electronic timepiece can be thin and flat.

Electronic timepiece and electronic apparatus

The driving portionis composed of multipolar motor. The multipolar motorincludes a coilfor multipolar motor, a statorfor multipolar motor, for transmitting a magnetic field from coil, and a rotorfor multipolar motorinstalled ratably in a stator hole of stator. A multipolar magnet is provided on a peripheral part of rotor. A plurality of teeth are formed on statortoward rotor. Clock hands for displaying time are installed on the rotation axis of rotor.

Electronic timepiece including rotary weight and antenna

Thermal energy is converted into a mechanical energy by a thermal converter that includes a phase change material whose phase changes between solid and liquid as a result of temperature changes in the operating environment. Because the phase change material does not change to the gas state during operation, good thermal conductivity can be achieved within a normal operating temperature range and sufficient mechanical energy can be obtained, thereby enhancing the conversion efficiency of the thermal converter. Also, because the case in which the phase material is contained is not required to be at a high pressure, the case can be easily manufactured and a compressing means such as a strong spring is not required, thus reducing a size of whole device.

Temperature difference drive unit, and electric device, timepiece and light electrical appliance having the same

An electronic device capable of increasing the braking torque applied to an electric power generator without causing a significant reduction in electric power generated by the electric power generator. The electronic device, which may be embodied in an electronically controlled mechanical clock, includes an electric power generator for converting mechanical energy transmitted from a spring via a wheel train to electrical energy, and a rotation controller for controlling the rotation period of the electric power generator. The rotation controller includes switches capable of connecting two terminals of the electric power generator in a closed-loop state, a chopping signal generator for generating two or more types of chopping signals which are different in duty ratio or frequency for use in a strong braking operation, and chopping signal selector that selects one of the chopping signals, wherein, in the strong braking operation, the selected chopping signal is applied to the switches so as to control the electric power generator in a chopping fashion. The strong braking operation is performed in one of two modes such that a higher priority is given to generation of electric power or the braking torque depending on the mode, thereby achieving an increase in the braking torque of the electric power generator without causing a significant reduction in the voltage generated by the electric power generator.

Growing community of inventors

Chino, Japan

Shigeyuki Fujimori