US3634730A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Circuit breaker including improved overcurrent protective device
Assignee: Westinghouse Electric Corp
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Filing: 1970-05-07
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Granted: 1972-01-11
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Expires: 1990-05-07
Abstract
Abstract A circuit breaker including separable contacts, an operating means or mechanism for opening and closing the contacts, and an overcurrent protective device including means which are responsive to the current in the separable contacts and in an electrical circuit which is being protected to actuate the operating means of the circuit breaker to trip or open the circuit breaker upon the occurrence of predetermined operating conditions. The protective device includes at least one means which is responsive substantially instantaneously when the current in the associated contacts or electrical circuit exceeds a predetermined value and an additional means which is connected to the first-mentioned means to render the first-mentioned means inoperative or to inhibit the operation of the first-mentioned means of the protective device during certain operating conditions of the circuit breaker.
Inventors
- 👤 John T Wilson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 14:19
CPC Classifications
H; H02; H02H; H02H7/00; H02H7/22; H02H7/222; H02H3/00; H02H3/08; H02H3/093
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
204 words
A circuit breaker comprising separable contacts, operating means for opening the contacts and for closing and latching in the contacts, and an overcurrent protective device operatively connected to said operating means and responsive to the current in said contacts for producing an output to actuate said operating means to open said contacts, said protective device including first means responsive to the current in said contacts for actuating said protective device to produce said output when the current in said contacts exceeds a first predetermined value after a predetermined time delay, second means responsive to the current in said contacts for independently actuating said protective device to produce said output substantially instantaneously when the current in said contacts exceeds substantially a second predetermined value which is substantially equal to the maximum current against which said operating means is capable of closing and latching in said contacts, and third means responsive to the current in said contacts for rendering said second means inoperative to actuate said protective device to produce said output when said contacts are closed by said operating means after substantially a predetermined time delay which is sufficient to allow a reasonable time for said operating means to close and latch in saId contacts.
Claim 2
Dependent Claim
204 words
A circuit breaker comprising separable contacts, operating means for opening the contacts and for closing and latching in the contacts, and an overcurrent protective device operatively connected to said operating means and responsive to the current in said contacts for producing an output to actuate said operating means to open said contacts, said protective device including first means responsive to the current in said contacts for actuating said protective device to produce said output when the current in said contacts exceeds a first predetermined value after a predetermined time delay, second means responsive to the current in said contacts for independently actuating said protective device to produce said output substantially instantaneously when the current in said contacts exceeds substantially a second predetermined value which is substantially equal to the maximum current against which said operating means is capable of closing and latching in said contacts, and third means responsive to the current in said contacts for rendering said second means inoperative to actuate said protective device to produce said output when said contacts are closed by said operating means after substantially a predetermined time delay which is sufficient to allow a reasonable time for said operating means to close and latch in saId contacts.
Claim 3
Dependent Claim
42 words
The combination as claimed in claim 1 wherein said third means is responsive to substantially a third predetermined value of the current in said contacts which is relatively less than said first and second predetermined values to initiate said predetermined time delay.
Claim 4
Dependent Claim
41 words
The combination as claimed in claim 1 wherein said second means comprises a level-detecting circuit responsive to the current in said contacts for producing an additional output substantially instantaneously when the current in said contacts exceeds substantially said second predetermined value.
Claim 5
Dependent Claim
36 words
The combination as claimed in claim 1 wherein said protective device includes a common output circuit connected to said first and second means for producing said output when independently actuated by said first and second means.
Claim 6
Dependent Claim
75 words
The combination as claimed in claim 1 wherein said separable contacts includes three sets of separable contacts and said protective device includes an additional means responsive to the currents in said three sets of contacts for deriving an output current which is substantially proportional to only the highest of the currents in said three sets of contacts, said first and second means being connected to said additional means to be responsive to said output current.
Claim 7
Dependent Claim
152 words
A circuit breaker comprising relatively movable contacts, operating means for opening said contacts and for closing and latching in said contacts, and an overcurrent-protective device operatively connected to said operating means and responsive to the current in said contacts for producing an output to actuate said operating means to open said contacts, said protective device including first and second means responsive to the current in said contacts for independently actuating said protective device to produce said output substantially instantaneously when the current in said contacts exceeds substantially first and second predetermined values, respectively, and third means responsive to the current in said contacts for rendering said first means inoperative to actuate said protective device to produce said output when said contacts are closed by said operating means after substantially a predetermined time delay which is sufficient to allow a reasonable time for said operating means to close nd latch in said contacts.
Claim 8
Dependent Claim
152 words
A circuit breaker comprising relatively movable contacts, operating means for opening said contacts and for closing and latching in said contacts, and an overcurrent-protective device operatively connected to said operating means and responsive to the current in said contacts for producing an output to actuate said operating means to open said contacts, said protective device including first and second means responsive to the current in said contacts for independently actuating said protective device to produce said output substantially instantaneously when the current in said contacts exceeds substantially first and second predetermined values, respectively, and third means responsive to the current in said contacts for rendering said first means inoperative to actuate said protective device to produce said output when said contacts are closed by said operating means after substantially a predetermined time delay which is sufficient to allow a reasonable time for said operating means to close nd latch in said contacts.
Claim 9
Dependent Claim
26 words
The combination as claimed in claim 6 wherein said second predetermined value of the current in said contacts is relatively greater than said first predetermined value.
Claim 10
Dependent Claim
42 words
The combination as claimed in claim 6 wherein said third means is responsive to substantially a third predetermined value of the current in said contacts which is relatively less than said first and second predetermined values to initiate said predetermined time delay.
Claim 11
Dependent Claim
50 words
The combination as claimed in claim 6 wherein said first means comprises a level-detecting circuit responsive to the current in said contacts for producing an additional output substantially instantaneously when the current in said contacts exceeds substantially said first predetermined value prior to the end of said predetermined time delay.
Claim 12
Dependent Claim
36 words
The combination as claimed in claim 6 wherein said protective device includes a common output circuit connected to said first and second means for producing said output when independently actuated by said first and second means.
Claim 13
Dependent Claim
79 words
The combination as claimed in claim 6 wherein said separable contacts of said circuit breaker includes three sets of separable contacts and said protective device includes an additional means responsive to the currents in said three sets of contacts for deriving an output current which is substantially proportional to only the highest of the currents in said three sets of contacts, said first and second means being connected to said additional means to be responsive to said output current.
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) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |