Kabushiki Kaisha Daini Seikosha

Shozo Kushida

Masataka Ikenishi

Joichi Miyazaki

Hiromasa Nakanishi

Tadahiro Kikuchi

Makoto Ueda

Masaharu Shida

Yukio Ikehata

Yasuichi Nakagawa

Koichi Tsukutani

Yukio Ikihata

Hirokazu Tsukutani

Yoshio Hozumi

An electronic timepiece having a stepping motor and a drive circuit responsive to a control signal for applying electrical drive pulses having polarities determined by the control signal for rotating the rotor of the stepping motor. The control circuit normally operates in a mode for applying a control signal to the drive circuit effective to control the drive circuit to apply alternate polarity electrical drive pulses to rotate the stepping motor rotor in a normal direction. Resetting circuitry is operable for correcting the time kept by the timepiece. A detecting circuit detects whether the stepping motor rotor is in a position to be rotated by a forthcoming drive pulse after resetting. If the stepping motor rotor is not in a position for rotation a detection circuit signal is applied to the control circuit so that the control signal controls the drive circuit to apply an electrical pulse effective to rotate the stepping motor rotor after resetting. Consequently, after resetting the immediately forthcoming drive pulse will have a polarity effective to rotate the stepping motor rotor and no time will be lost.

Electronic watch

In an electronic watch a non-operation detecting circuit detects the non-operative condition of the stepping motor of the watch and produces a non-operation signal each time the stepping motor fails to operate in response to the standard pulse which drives the same. A counter counts the number of non-operation signals and stores the count for later use. A rotation detecting circuit detects the resumption of operation of the stepping motor in response to the standard pulse from the non-operative condition and a quick feed control circuit quickly advances the stepping motor in response to an input from the rotation detection circuit by thereafter supplying, instead of the standard pulses, the quick feed pulses to the drive circuit for the motor equal in number to the number of the non-operation signals counted in the counter. In this way the corrected time will be displayed by the watch even after being rendered inoperative as a result of an external condition such as low temperature or a high strength DC magnetic field.

An electronic watch movement including a base plate having a pair of opposite major surfaces. A calendar ring is disposed confronting a first of the major surfaces, and a circuit board is disposed confronting the second major surface. The calendar ring has a narrow central annular portion, a wide peripheral skirt portion circumscribing the narrow central annular portion and a circular step portion extending between the narrow central annular portion and the wide peripheral skirt portion. The skirt portion of the calendar ring is spaced further from the base plate then the central annular portion of the calendar ring. The base plate has openings therethrough opposite the skirt portion of the calendar ring, and electronic watch components are mounted on the major surface of the circuit board and extend through the openings through the base plate beyond the narrow central annular portion of the calendar ring toward the wide peripheral skirt portion of the calendar ring. The electronic watch components are oriented to minimize the thickness of the electronic watch movement.

A calender mechanism comprising a cannon wheel having a gear wheel portion and a cylindrical portion extending axially from the gear wheel portion, a day star wheel mounted for rotation on a cylindrical portion of the cannon wheel, and a positioning plate. The day star wheel has an outer diameter less than that of the gear wheel portion of the cannon wheel, and the positioning plate is positioned to partially overlie the outer peripheral portion of the gear wheel portion for preventing the cannon wheel from traveling axially toward the day star wheel. The portion of the positioning plate overlying the outer peripheral portion of the cannon wheel does not extend between the day star wheel and the gear wheel portion of the cannon wheel.

Calendar mechanism of a portable timepiece

A timepiece gear train structure comprises a center wheel and pinion mounted between a third wheel bridge and a date wheel holder without use of a train wheel bridge as is customarily used in such gear train structures. A plate extends between the third wheel bridge and the date wheel holder and has an opening therein through which extends the intermediate part of the center wheel and pinion thereby rotably supporting the intermediate part thereof. The lower part of the center wheel and pinion is rotatably supported by the date wheel holder by means of a cannon pinion which encircles the lower part, an hour wheel which encircles the cannon pinion and a bush encircling a portion of the hour wheel and being fixed to the date wheel holder.

Train structure of a timepiece

Second adjustment system in an electronic watch employing a quartz oscillator as a time base. The watch comprises a standard oscillating circuit including the quartz oscillator, a divider, a driving circuit, and a converter. The divider produces several oscillatory output signals of different frequency so as to produce diverse time signals. A time signal selection switch selects output among these outputs. The selected output time signal corresponds to the signal required for adjusting a time delay or a time advance of the seconds indicated by the watch. An incorrect time is corrected during normal watch operation by this second adjustment system.

Second adjustment system in an electronic watch

A watch movement comprises upper and lower spaced-apart plates between which are mounted the major components of the watch movement. Manufacturing indicia indicative of the manufacturer, date, serial number and other particulars of the watch movement are disposed on the top face of the lower plate, facing the upper plate, and corresponding openings are provided in the upper plate overlying the indicia so that the manufacturing indicia is readily visible through the openings. Magnifying lenses may be disposed over the openings to magnify the indicia visible therethrough.

Marking display assembly in a watch movement

A switching mechanism in an electronic watch including a clicking mechanism comprising a clicking cam which is mounted for rotation on an operative rod and a spring which is fixed to a base plate. The clicking cam is provided with a peripheral projecting portion. The spring is provided with a convex portion. In a switching operation, the projecting portion of the cam engages with the convex portion of the spring during the rotation of the cam which is rotated together with the operative rod. After passing through a dead point where the cam disengages with the spring, the cam continues to rotate due to the restoring force of the spring. Then, a click sound is produced at the engagement and the disengagement therebetween.

Switching mechanism in an electronic watch

A switching mechanism for a timepiece comprising a base plate having first and second bores extending therethrough and intersecting, a circuit board having a surface opposite the second bore and having stationary contacts mounted on the surface opposite the second bore, and a contact member disposed within the second bore and dimensioned to slide therein. The contact member has a transverse bore extending therethrough and alignable with the first bore through the base plate, and the contact member has a conductive lower end portion extending from the base plate and terminating at a contact surface for contacting to electrically connect the stationary contacts on the circuit board. A spring biases the contact member downwardly to a lowered position with the contact surface contacting the stationary contacts on the surface board. A timepiece adjusting stem has an end portion dimensioned for insertion into the first bore and into the traverse bore for maintaining the contact member at a raised position with the contact surface thereof raised from the stationary contacts, and the adjusting stem is slideably mounted in a position aligned with the second bore for permitting the adjusting stem to travel in an axial direction thereof between a retracted position with the stem clear of the transverse bore of the contact member and an operative position with the stem inserted into the first bore of the base plate and into the transverse bore of the contact member to maintain the contact member in a raised position. The transverse bore has a tapered converging portion converging in an inward direction of the contact member so that the end portion of the stem bears against the tapered portion as the stem travels from the retracted to the operative position thereby causing the contact member to rise as the tapered portion of the transverse bore climbs the end portion of the stem traveling inwardly of the contact member until the stem extends into the transverse bore to maintain the contact member in a raised position.

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Tokyo, Japan

Shozo Kushida