Citizen Watch Company, Ltd.

Cimeo Precision Co., Ltd.

Toshio Murata

Masataka Matsumoto

Akira Azuma

Akio Aoki

Takao Saito

Ikuo Kobayashi

Tadashi Nakamura

Kenji Irie

Masami Fukuda

Tadao Enomoto

Masahiko Waki

Hachiro Kushida

Hisao Yamagata

Junsuke Kashikie

Michihiro Iwamura

Teruhiko Fujii

Junichi Nishikawa

Fumio Takeuchi

Eiichi Kitabayashi

Yurie Udo

The present invention provides a timepiece having a light-receptive/emitting device such as a solar cell and an EL device in which a parting portion can be set freely and the timepiece can be adapted to various design requests. The timepiece has a dial for displaying a time, a timepiece movement incorporating driving units, a light-receptive/emitting device provided between the timepiece movement and the dial, and an armoring member for housing the timepiece movement, in which a portion or a whole of the dial is formed to have a light-transmitting property so as to supply outside light to the light-receptive/emitting device or to allow the light-receptive/emitting device to emit light to an outside, the light-receptive/emitting device is fixed to one side of the timepiece movement, and the dial is mounted to the armoring member by engaging a first portion formed at the dial with a second portion formed at the armoring member.

Timepiece

A solar-cell watch dial to be disposed on or above a solar cell housed in a watch, the solar-cell watch dial including an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90% and exhibiting a light transmission ranging from 40 to 60%. The invention also includes a process for producing a solar-cell watch dial, which includes the steps of: mixing together an alumina of the formula Al.sub.2 O.sub.3 whose purity is at least 99.90%, an organic binder and water to thereby obtain an Al.sub.2 O.sub.3 mixture (A); drying and granulating the Al.sub.2 O.sub.3 mixture to thereby obtain a granular material (B); molding the granular material into a plate dial precursor (C); firing the dial precursor at 700 to 1500.degree. C. in atmospheric environment to thereby obtain a preliminary firing product (D); and firing the preliminary firing product at 1500 to 1800.degree. C. under a pressure of 1.times.10.sup.-2 to 1.times.10.sup.-5 torr for 1 to 10 hr to thereby obtain a solar-cell watch dial (E). The solar-cell watch dial of the present invention enables preventing the solar cell from being sighted from outside without hindering the supply of light energy to the solar cell.

Process for producing solar-cell watch dial

Solar-cell watch dial and process for producing the same

Watch having a sensor

A structure comprising a watch case; a pair of lugs each extending from the watch case and having an upper surface in a lower position than the upper surface of the watch case; a band; and a connector secured to the underside of the end portion of the band, the band being closely attached to the watch case by placing the end of the band on the upper surfaces of the lugs and tightening cone point screws into threaded holes provided near distal ends of the sides of the lugs so that the cone points of the screws hold firmly a pair of attachment openings provided in said connector against the watch case.

Watch case and band attachment structure

The invention provides a means for solving the difficult problem of the deposition of stain in the recesses to cause loss of beautiful appearance on the matted surface of an article for personal ornament made of titanium, zirconium or an alloy thereof formed by honing or barrel finishing. The method comprises the steps of (a) forming a first matted surface with microscopically fine protrusions and recesses on the article by honing or barrel finishing, (b) forming a hardened layer on the matted surface by nitriding, carbonizing, boriding or oxidizing, (c) partially removing the hardened layer covering the protrusions on the matted surface by a first electrolytic or chemical polishing, (d) forming a second matted surface on the article by honing or barrel finishing, and (e) partially removing the surface layer at the protrusions by a second electrolytic or chemical polishing to smoothen the surface leaving a sandy appearance.

Method for finishing matted surface on a metal-made article for personal

A water-resistant device for a watchcase of a diver's watch having a case body, a back and a glass. The device comprises an O-ring for sealing the watchcase, an annular leaf spring having an elasticity in the axial direction of the watchcase, and a bezel for the glass for compressing the leaf spring so as to urge the glass to the O-ring for maintaining watertightness of the watchcase. The O-ring and leaf spring are such that when the glass is moved by the difference between the pressure in the watchcase and atmospheric pressure, gases in the watchcase leak out through a gap formed by the movement of the glass.

Water-resisting structure for a watch

A diver's watch having a watch case and a register ring which is rotatably mounted on the watch case to set a diving time. The register ring has a plurality of notches on the underside thereof and is urged by clicks made of spring plate and held by a holding ring secured to the watch case. A plurality of lock notches are formed on the outer periphery of the watch case. A lock pin is projected from the inside of the register ring and engaged with one of the lock notches, so that the register ring is locked to the watch case. When the register ring is depressed against the clicks, the lock pin disengages from the lock notch, so that the register ring can be rotated.

Structure for preventing the rotating of a register ring of a diver's

A timepiece push-button structure comprising a spring member composed of tongue portions interconnected by a connection portion, each tongue portion being bridge-shaped so that the central portion is raised while both end portions of the central portion abut against a pressure conductive rubber holder, each tongue portion further including a substantially centrally located arcuate notch and a bifurcation extending therefrom. A push-button having a groove is adapted to engage said notch, and a pressure conductive rubber is adapted for the application of pressure and disposed directly below the push-button.

Timepiece push-button structure

A sound emitting device for an electronic timepiece comprising a disk-shaped permanent magnet; a first yoke and second yoke introducing magnetic flux produced by the magnet and forming, outside the periphery of the magnet, a magnetic gap having the magnetic flux in the vertical direction of the perimeter of the magnet and in the horizontal direction of the disk surfaces of the magnet; a diaphragm carrying, within the magnetic flux of the magnetic gap, a moving coil wound at right angles to the magnetic flux and adapted to be vibrated in response to sound signal currents sent to the moving coil; and a support member supporting the permanent magnet, the yokes as well as the diaphragm at the diaphragm peripheral portion and removably secured at the support frame peripheral portion to a case. Air openings are provided in a part of the support member except where the permanent magnet, yokes and diaphragm are supported to form an air chamber which opens to the back of the diaphragm when the support member is packaged in the timepiece case.

Sound emitting device for electronic timepiece

Growing community of inventors

Tanashi, Japan

Toshio Murata