US3878501A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Asymmetrical dual PTCR package for motor start system
Assignee: Sprague Electric Co
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Filing: 1974-01-02
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Granted: 1975-04-15
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Expires: 1994-01-02
Abstract
Abstract A motor start and run system for a single phase motor provides a predetermined period for starting the motor during which power is delivered to a start winding of the motor. It also provides a time delay after the motor is deenergized before the motor may be restarted. These two control times are essentially determined by thermal time constants associated with a package having two PTCRs. These two PTCRs are thermally coupled and have different anomaly temperatures. A dual-PTCR package is also disclosed for use in said motor start system having provision for strongest thermal coupling with the environment for the PTCR having the higher anomaly temperature.
Inventors
- 👤 William L Moorhead
- 👤 Manfred Kahn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 22:05
CPC Classifications
H; H01; H01C; H01C7/00; H01C7/02; H01C7/022
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
53 words
A PTCR package comprising a first and a second PTCR being thermally coupled therebetween, said first PTCR having a lower anomaly temperature than said second PTCR, and a selective heat removal means for providing stronger thermal coupling of said second PTCR than that of said first PTCR to the environment of said package.
Claim 2
Dependent Claim
53 words
A PTCR package comprising a first and a second PTCR being thermally coupled therebetween, said first PTCR having a lower anomaly temperature than said second PTCR, and a selective heat removal means for providing stronger thermal coupling of said second PTCR than that of said first PTCR to the environment of said package.
Claim 3
Dependent Claim
45 words
The PTCR package of claim 1 further comprising a metal plate wherein said thermal coupling between said PTCRs is accomplished by mounting said first and second PTCRs to opposite sides of said metal plate, an extension of said plate serving as a common lead thereto.
Claim 4
Dependent Claim
87 words
The PTCR package of claim 1 further comprising a first and second metal plate being mounted to opposite sides of said first PTCR, a third and fourth metal plate being mounted to opposite sides of said second PTCR, and an electrically insulating layer, said thermal coupling between said PTCRs being accomplished by mounting said insulating layer between said second plate and said third plate, and said plates each having an extEnsion serving as an electrical lead so that independent electrical access is provided to each said PTCR.
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) | 1978-04-14 | 1978-10-14 | 1979-04-15 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-04-14 | 1982-10-14 | 1983-04-15 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-04-14 | 1986-10-14 | 1987-04-15 | $7700.00 | Window Closed / Lapsed |