US3842327A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Solid state start and control circuit for a. c. motor
Assignee: Philips North America LLC
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Filing: 1973-10-25
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Granted: 1974-10-15
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Expires: 1993-10-25
Abstract
Abstract A starting and controlling circuit for a split phase a.c. motor is disclosed. The circuit employs solid state circuitry for all high level switching and is actuatable by a low-level d.c. logic signal. The start winding and starting capacitor are switched out of the starting circuit by means of an inductor which controls the switching of a triac switch.
Inventors
- 👤 J Wexler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 11:30
CPC Classifications
H; H02; H02P; H02P1/00; H02P1/16; H02P1/42; H02P1/44
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
208 words
A circuit for controlled starting of an a.c. driven motor having a two-terminal start winding and a two-terminal run winding comprising: a first bilateral controllable semiconductor switch having first and second main electrodes and a control electrode, said first main electrode adapted to being coupled to one terminal of said start winding of said motor, said control electrode adapted to being connected to one terminal of said run winding; means connected between the control electrode of said first switch and the second main electrode of said first switch responsive to the current through the run winding for developing a voltage inversely related to the speed of the motor; a second bilateral controllable semiconductor switch having first and second main electrodes and a control electrode, said second electrode being coupled to the second electrode of said first semiconductor switch; means for coupling a first terminal of a high level a.c. signal source to the other terminals of said start and run windings and for coupling a second terminal of said high level signal source to the first main electrode of said second semiconductor switch; and a low-level, controlled switch for coupling the control electrode of the second semiconductor switch with the second main electrode of said second semiconductor switch.
Claim 2
Dependent Claim
208 words
A circuit for controlled starting of an a.c. driven motor having a two-terminal start winding and a two-terminal run winding comprising: a first bilateral controllable semiconductor switch having first and second main electrodes and a control electrode, said first main electrode adapted to being coupled to one terminal of said start winding of said motor, said control electrode adapted to being connected to one terminal of said run winding; means connected between the control electrode of said first switch and the second main electrode of said first switch responsive to the current through the run winding for developing a voltage inversely related to the speed of the motor; a second bilateral controllable semiconductor switch having first and second main electrodes and a control electrode, said second electrode being coupled to the second electrode of said first semiconductor switch; means for coupling a first terminal of a high level a.c. signal source to the other terminals of said start and run windings and for coupling a second terminal of said high level signal source to the first main electrode of said second semiconductor switch; and a low-level, controlled switch for coupling the control electrode of the second semiconductor switch with the second main electrode of said second semiconductor switch.
Claim 3
Dependent Claim
11 words
The circuit of claim 1 wherein said semiconductor switches are triacs.
Claim 4
Dependent Claim
17 words
The circuit of claim 1 wherein said means for developing a speed responsive voltage is an inductor.
Claim 5
Dependent Claim
24 words
The circuit of claim 1 wherein a capacitor is included between the control electrode and the second main electrode of said first semiconductor switch.
Claim 6
Dependent Claim
23 words
The circuit of claim 1 wherein said low-level controlled switch is a d.c. controlled reed relay having a single pole, single throw contact.
Claim 7
Dependent Claim
19 words
The circuit of claim 5 wherein said single pole, single throw contact is in series with a current-limiting resistor.
Claim 8
Dependent Claim
32 words
The circuit of claim 1 which iNcludes a series circuit of a resistor and capacitor, one of such series circuits being connected across the main electrodes of each of the semiconductor switches.
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) | 1977-10-14 | 1978-04-15 | 1978-10-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-10-14 | 1982-04-15 | 1982-10-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-10-14 | 1986-04-15 | 1986-10-15 | $7700.00 | Window Closed / Lapsed |