Patent US3908110A successfully refreshed from Google Patents.
US3908110A
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US
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Method for calibrating an electric circuit breaker
Assignee: General Electric Co
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Filing: 1974-10-09
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Granted: 1975-09-23
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Expires: 1994-10-09
Abstract
Abstract A circuit breaker designed for automated assembly includes pairs of fixed and movable contacts, the latter carried by a carrier mounted for reciprocating movement in the breaker case. Operating and trip mechanism parts are mounted on a frame positioned in the case. A handle slideably mounted by the case actuates the operating mechanism to open and closed circuit positions. A fixture is utilized with the frame for calibrating the thermal trip setting and for partial assembly of the operating mechanism.
Inventors
- 👤 Eldon Bertel Heft
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 15:44
CPC Classifications
G; G01; G01R; G01R35/00; G01R35/005; H; H01; H01H; H01H11/00; H01H11/0062; H01H69/00; H01H69/01; H01H2011/0075; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49105; Y10T29/49826; Y10T29/49895; Y10T29/49901; Y10T29/51; Y10T29/5176; Y10T29/53; Y10T29/5313; Y10T29/532; Y10T29/53248
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
198 words
A method of calibrating the thermal trip setting of a thermalmagnetic trip mechanism utilized in an electric circuit breaker, wherein the trip mechanism includes a bimetallic element deflectable in response to overload current through the circuit breaker, an electromagnet mounted by the bimetallic element and responsive to high magnitude fault current levels for attracting an armature, movement of the armature unlatching the circuit breaker operating mechanism to trip the circuit breaker, an armature stop for establishing the quiescent position of the armature, and a hook mounted by the metallic element and having a tip for engaging and moving the armature to trip the circuit breaker upon deflection of the bimetallic element in response to sustained overload current levels, said method comprising the steps of: A. placing the trip mechanism in a fixture with the paRts thereof assuming relative positions identical to the relative positions they would normally assume in an operative circuit breaker; B. referencing the fixture in a predetermined fixed spatial position; and C. machining away a portion of a particular part of the trip mechanism so as to establish a predetermined operative positional relationship between the hook and the armature when positioned against the armature stop.
Claim 2
Independent Claim
198 words
A method of calibrating the thermal trip setting of a thermalmagnetic trip mechanism utilized in an electric circuit breaker, wherein the trip mechanism includes a bimetallic element deflectable in response to overload current through the circuit breaker, an electromagnet mounted by the bimetallic element and responsive to high magnitude fault current levels for attracting an armature, movement of the armature unlatching the circuit breaker operating mechanism to trip the circuit breaker, an armature stop for establishing the quiescent position of the armature, and a hook mounted by the metallic element and having a tip for engaging and moving the armature to trip the circuit breaker upon deflection of the bimetallic element in response to sustained overload current levels, said method comprising the steps of: A. placing the trip mechanism in a fixture with the paRts thereof assuming relative positions identical to the relative positions they would normally assume in an operative circuit breaker; B. referencing the fixture in a predetermined fixed spatial position; and C. machining away a portion of a particular part of the trip mechanism so as to establish a predetermined operative positional relationship between the hook and the armature when positioned against the armature stop.
Claim 3
Dependent Claim
16 words
The method defined in claim 1, wherein a portion of the hook tip is machined away.
Claim 4
Dependent Claim
16 words
The method defined in claim 1, wherein a portion of the armature stop is machined away.
Claim 5
Dependent Claim
25 words
The method defined in claim 1, wherein said machining step is performed by a laser beam trained on a particular part of the trip mechanism.
Claim 6
Dependent Claim
16 words
The method defined in claim 4, wherein the laser beam is trained on the hook tip.
Claim 7
Dependent Claim
16 words
The method defined in claim 4 wherein the laser beam is trained on the armature stop.
References Cited (Backward Citations)
US3200217A
Cited
US3803379A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-09-22 | 1979-03-24 | 1979-09-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-09-22 | 1983-03-24 | 1983-09-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-09-22 | 1987-03-24 | 1987-09-23 | $7700.00 | Window Closed / Lapsed |