Patent US4375613A successfully refreshed from Google Patents.
US4375613A
Expired / Lapsed
US
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Electrical control circuit
Assignee: Individual
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Filing: 1979-07-26
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Granted: 1983-03-01
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Expires: 1999-07-26
Abstract
Abstract The present invention concerns electrical control circuits which are particularly applicable to use and controlling the starting of electric motors. The invention thus provides a sensing and switching circuit capable of automatically to bring into and out of operation the start winding of an electric motor at appropriate motor speeds. Appropriate means sense a voltage or current level and a trigger response to the sensed value to supply firing pulses to the gate of a triac. The trigger element is preferably an M.O.S. integrated circuit multivibrator.
Inventors
- 👤 Paul Fuller
- 👤 Roderick W. Froud
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 10:48
CPC Classifications
H; H02; H02P; H02P1/00; H02P1/16; H02P1/42; H02P1/44; H02P1/445
Claims Analysis
Total Claims: 3
Claim 1
Independent Claim
148 words
In a circuit arrangement for use with electric motors having a start winding and a run winding and comprising (a) sensing means having an output and operative to generate a control signal at said output in response to the flow of current in said run winding, (b) threshold means responsive to said control signal to generate a firing signal in response to said control signal exceeding a predetermined threshold, and (c) means connected to said threshold means so as to be responsive to said firing signal and operative to control the supply of current to said start winding, the improvement wherein said threshold means comprises an MOS integrated circuit multivibrator operative to generate said firing signal as a pulse train, said output of said sensing means being connected to the supply inputs of said multivibrator whereby said threshold is defined by the inherent switching characteristics of said multivibrator.
Claim 2
Dependent Claim
148 words
In a circuit arrangement for use with electric motors having a start winding and a run winding and comprising (a) sensing means having an output and operative to generate a control signal at said output in response to the flow of current in said run winding, (b) threshold means responsive to said control signal to generate a firing signal in response to said control signal exceeding a predetermined threshold, and (c) means connected to said threshold means so as to be responsive to said firing signal and operative to control the supply of current to said start winding, the improvement wherein said threshold means comprises an MOS integrated circuit multivibrator operative to generate said firing signal as a pulse train, said output of said sensing means being connected to the supply inputs of said multivibrator whereby said threshold is defined by the inherent switching characteristics of said multivibrator.
Claim 3
Dependent Claim
68 words
A circuit arrangement according to claim 1 wherein said means responsive to said firing signal comprises a semi-conductor device having a gate electrode, and further including: (a) differentiating means operative to differentiate the train of pulses generated by said multivibrator, (b) a transistor to the base of which the output of said differentiating means is connected, said transistor being connected to said gate of said semi-conductor switching device.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-02-28 | 1986-08-30 | 1987-03-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-02-28 | 1990-08-30 | 1991-03-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-02-28 | 1994-08-30 | 1995-03-01 | $7700.00 | Window Closed / Lapsed |