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US4371269A Expired / Lapsed US ⏱️ 0.0 years remaining

D-C Voltage converter for a wristwatch

Assignee: MIGOWSKI FRIEDRICH-K CALW-HIRSAU FEDERAL REPUBLIC OF GERMANY
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Filing: 1980-09-09
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Granted: 1983-02-01
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Expires: 2000-09-09
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Abstract

Abstract A d-c converter for inclusion in a miniature electronic device, such as an electronic wristwatch having a d-c supply source, the converter functioning to increase or decrease the voltage of this source. The converter includes a transformer whose primary is connected to the source through a periodically-actuated chopper to produce an alternating voltage, the secondary of the transformer being connected to a rectifier circuit having at least one controllable switch element whose on-off state is governed in synchronism with the chopper whereby the switch element acts to rectify the secondary voltage.

Inventors

  • 👤 Hans-Rudolf Sutter

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-03 02:00
CPC Classifications
G; G04; G04G; G04G19/00; G04G19/02

Claims Analysis

Total Claims: 16
Claim 1
Independent Claim 151 words
An electronic wristwatch provided with a low voltage d-c supply source and an electronic circuit having a high-frequency time base whose output is coupled to a multi-stage frequency divider whose output stage yields low-frequency timing pulses to actuate a time display, and a converter which functions to increase the voltage of the source to a level sufficient to energize the electronic circuit, said converter comprising: (A) a transformer having a primary and a secondary; (B) a periodically-actuated chopper interposed between the source and the primary whereby an a-c voltage is induced in the secondary; (C) a rectifier circuit connected to the secondary and having at least one controllable switch element; and (D) means to derive intermediate frequency pulses from an intermediate stage of the divider to govern the on-off state of said switch element in synchronism with the periodically-actuated chopper to cause said element to effect rectification of the a-c voltage.
Claim 2
Dependent Claim 151 words
An electronic wristwatch provided with a low voltage d-c supply source and an electronic circuit having a high-frequency time base whose output is coupled to a multi-stage frequency divider whose output stage yields low-frequency timing pulses to actuate a time display, and a converter which functions to increase the voltage of the source to a level sufficient to energize the electronic circuit, said converter comprising: (A) a transformer having a primary and a secondary; (B) a periodically-actuated chopper interposed between the source and the primary whereby an a-c voltage is induced in the secondary; (C) a rectifier circuit connected to the secondary and having at least one controllable switch element; and (D) means to derive intermediate frequency pulses from an intermediate stage of the divider to govern the on-off state of said switch element in synchronism with the periodically-actuated chopper to cause said element to effect rectification of the a-c voltage.
Claim 3
Dependent Claim 16 words
An electronic watch as set forth in claim 1, wherein said switch element is a transistor.
Claim 4
Dependent Claim 30 words
An electronic watch as set forth in claim 2, wherein said rectifier circuit includes a plurality of transistors in a full-wave rectifier network, each transistor functioning as a switch element.
Claim 5
Dependent Claim 18 words
An electronic watch as set forth in claim 3, wherein said plurality is constituted by four MOS-FET transistors.
Claim 6
Dependent Claim 18 words
An electronic watch as set forth in claim 1, wherein said switch element is a field-controlled integrated-circuit microswitch.
Claim 7
Dependent Claim 24 words
An electronic watch as set forth in claim 1, further including an accumulator coupled to the output of said rectifier circuit and charged thereby.
Claim 8
Dependent Claim 39 words
An electronic watch as set forth in claim 6, further including a comparator responsive to the voltage of said d-c source and adapted to disable the converter when the voltage supplied by said source lies outside a given range.
Claim 9
Dependent Claim 43 words
An electronic watch as set forth in claim 6, further including a comparator responsive to the voltage of said d-c source and adapted to disconnect said accumulator from the rectifier circuit when the voltage supplied by said source lies outside a given range.
Claim 10
Dependent Claim 52 words
An electronic watch as set forth in claim 1, wherein said wristwatch has a case provided with a metal part that makes contact with the wrist of the wearer, said d-c source being constituted by a thermogenerator having positive and negative poles, one of which is thermally coupled to said metal part.
Claim 11
Dependent Claim 65 words
An electronic watch as set forth in claim 9, wherein said transformer primary has a centertap and the other pole of said thermogenerator is connected to the centertap of said transformer primary and the one pole is connected to the ends of the primary through respective controllable switch elements, said intermediate frequency pulses derived from said frequency divider acting to actuate said elements in push-pull.
Claim 12
Dependent Claim 41 words
An electronic watch as set forth in claim 10 having a stepping motor provided with a rotor for driving the hands of an analog time display, said motor having a stator winding which also functions as the secondary of said transformer.
Claim 13
Dependent Claim 60 words
An electronic watch as set forth in claim 11, further including a decoder activated by said frequency divider and functioning to define the duration of said timing pulses for driving the stepping motor, the interval between successive driving pulses being short relative to the duration of the driving pulses, and means to short circuit said stator winding during said interval.
Claim 14
Dependent Claim 44 words
An electronic watch as set forth in claim 12, further including a comparator responsive to the level of voltage supplied by said source, and logic control means coupled to said comparator to disable said rectifier circuit switch element when said voltage level is insufficient.
Claim 15
Dependent Claim 37 words
An electronic watch as set forth in claim 13, wherein said rectifier circuit includes four transistors acting as switch elements in a full-wave rectification network, and said chopper is constituted by a pair of controllable switch elements.
Claim 16
Dependent Claim 39 words
An electronic watch as set forth in claim 14, wherein said logic control means coupled to said comparator acts via a flip-flop to disable said rectifier circuit transistors and said chopper switch elements when said voltage level is insufficient.

References Cited (Backward Citations)

US3701937A Cited
US3859586A Cited
US4134057A Cited
US4291266A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-01-31 1986-08-02 1987-02-01 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-01-31 1990-08-02 1991-02-01 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-01-31 1994-08-02 1995-02-01 $7700.00 Window Closed / Lapsed

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