Patent US3716757A successfully refreshed from Google Patents.
US3716757A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit breaker with thermal tripping device
Assignee: Individual
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Filing: 1972-02-03
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Granted: 1973-02-13
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Expires: 1992-02-03
Abstract
Abstract A circuit breaker actuated automatically electrically for interrupting current supply from a multiphase circuit to a load accomplished by a series overcurrent tripping device. An operating coil of the main circuit interruptor has one terminal connected to one phase of the power circuit and its other terminal connected to a movable control contact in a control circuit connected to the other phase of the power circuit. The overcurrent tripping device is a bimetallic device that functions as a thermal tripping device functioning to actuate the control contact to a position closing the control circuit to energize the operating coil and interrupt the main circuit supply to the load when an overload or short circuit obtains. When the overload or short circuit is removed the bimetallic device cools and the control contact, which is biased to a rest position breaking the control circuit, is restored automatically to its rest position so that the main circuit interruptor is deenergized and automatically allows closing of its main contacts that make-andbreak the supply circuit to the load.
Inventors
- 👤 A Rodriguez
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 13:40
CPC Classifications
H; H02; H02H; H02H3/00; H02H3/02; H02H3/06; H02H3/066; H01; H01H; H01H81/00; H01H81/02
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
187 words
A circuit-protective apparatus connectable to a power circuit having a load connected thereto comprising, a circuit breaker having electromagnetic means having contacts biased to a closed position and connected in operation in series with said load, means for opening said series contacts when an overload or short circuit exists comprising an operating coil energizable for actuating said series contacts to an open position, a control circuit connected to said power circuit in operation for controlling energizing of said operating coil comprising a quickmake and quick-break control contact biased to a rest position maintaining the control circuit open and the operating coil deenergized in the absence of an over load or short circuit and operable to a second position closing the control circuit to energize said operating coil for opening said series contacts, a thermal tripping device in series with said load for actuating said control contact to said second position when an overload or short circuit exists, and maintaining means connected to said power circuit and said control circuit for maintaining said operating coil energized when said series contacts are open thereby maintaining said series contacts open.
Claim 2
Dependent Claim
187 words
A circuit-protective apparatus connectable to a power circuit having a load connected thereto comprising, a circuit breaker having electromagnetic means having contacts biased to a closed position and connected in operation in series with said load, means for opening said series contacts when an overload or short circuit exists comprising an operating coil energizable for actuating said series contacts to an open position, a control circuit connected to said power circuit in operation for controlling energizing of said operating coil comprising a quickmake and quick-break control contact biased to a rest position maintaining the control circuit open and the operating coil deenergized in the absence of an over load or short circuit and operable to a second position closing the control circuit to energize said operating coil for opening said series contacts, a thermal tripping device in series with said load for actuating said control contact to said second position when an overload or short circuit exists, and maintaining means connected to said power circuit and said control circuit for maintaining said operating coil energized when said series contacts are open thereby maintaining said series contacts open.
Claim 3
Dependent Claim
187 words
A circuit-protective apparatus connectable to a power circuit having a load connected thereto comprising, a circuit breaker having electromagnetic means having contacts biased to a closed position and connected in operation in series with said load, means for opening said series contacts when an overload or short circuit exists comprising an operating coil energizable for actuating said series contacts to an open position, a control circuit connected to said power circuit in operation for controlling energizing of said operating coil comprising a quick-make and quick-break control contact biased to a rest position maintaining the control circuit open and the operating coil deenergized in the absence of an over load or short circuit and operable to a second position closing the control circuit to energize said operating coil for opening said series contacts, a thermal tripping device in series with said load for actuating said control contact to said second position when an overload or short circuit exists, and maintaining means connected to said power circuit and said control circuit for maintaining said operating coil energized when said series contacts are open thereby maintaining said series contacts open.
Claim 4
Dependent Claim
187 words
A circuit-protective apparatus connectable to a power circuit having a load connected thereto comprising, a circuit breaker having electromagnetic means having contacts biased to a closed position and connected in operation in series with said load, means for opening said series contacts when an overload or short circuit exists comprising an operating coil energizable for actuating said series contacts to an open position, a control circuit connected to said power circuit in operation for controlling energizing of said operating coil comprising a quick-make and quick-break control contact biased to a rest position maintaining the control circuit open and the operating coil deenergized in the absence of an over load or short circuit and operable to a second position closing the control circuit to energize said operating coil for opening said series contacts, a thermal tripping device in series with said load for actuating said control contact to said second position when an overload or short circuit exists, and maintaining means connected to said power circuit and said control circuit for maintaining said operating coil energized when said series contacts are open thereby maintaining said series contacts open.
Claim 5
Dependent Claim
173 words
A circuit-protective apparatus connectable to a power circuit according to claim 1, in which said operating coil has a terminal connected to said power circuit and another terminal connected to said control contact, means connecting the series contacts in operation in parallel with said operating coil, said control circuit including a fixed contact connected in operation to said Power circuit and contacted by said control contact in said second position thereof, means connecting said first fixed contact in operation to said power circuit defining a branch of said control circuit in parallel with said load and thermal tripping device when said control contact closes said control circuit, whereby when said control contact is in said second position said branch circuit and said operating coil are in series and in parallel with said load, said thermal tripping device and said series contacts, a second fixed contact in said control circuit contacted by said control contact in its rest position thereof, means connecting said second contact intermediate said thermal tripping device and said series contacts.
Claim 6
Dependent Claim
45 words
A circuit-protective apparatus connectable to a power circuit according to claim 2, in which said thermal tripping device comprises a deflectable bimetallic element deflecting when heated in a direction for actuating said control contact to said second position, and a shunt across said bimetallic element.
Claim 7
Dependent Claim
75 words
A circuit-protective apparatus connectable to a power circuit according to claim 3, in which said series contacts comprise a pair of contacts, means connecting said load and said thermal tripping device intermediate said pair of series contacts, and a resistor in parallel with one of said pair of series contacts connected to said power circuit and said branch circuit to maintain said operating coil energized when said one of said pair of contacts is open.
Claim 8
Dependent Claim
44 words
A circuit-protective apparatus connectable to a power circuit according to claim 1, in which said thermal tripping device comprises a bimetallic element which snaps in said direction for actuating said control contact when heated to a selected temperature corresponding to a selected overload level.
Claim 9
Dependent Claim
84 words
A circuit-protective apparatus connectable to a power circuit according to claim 1, in which said electromagnetic means comprises means for opening said series contacts in sequence, said series contacts comprising a pair of contacts each connected in operation to a respective phase of said power circuit, and said maintaining means comprising a resistor connected in use to one phase of said power circuit and said control circuit across one of the series contacts to maintain said operating coil energized when said contacts are open.
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) | 1976-02-13 | 1976-08-14 | 1977-02-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-02-13 | 1980-08-14 | 1981-02-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-02-13 | 1984-08-14 | 1985-02-13 | $7700.00 | Window Closed / Lapsed |