Patent US3849751A successfully refreshed from Google Patents.
US3849751A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electric circuit breakers
Assignee: Cutler Hammer Inc
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Filing: 1973-02-06
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Granted: 1974-11-19
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Expires: 1993-02-06
Abstract
Abstract An apparatus for improving the assembly and operation of an electric circuit breaker is disclosed wherein pivotally mounted contact arm assemblies and a releasable trip lever, retained by a current-responsive latch system are interconnected by a toggle linkage and springs to a manually movable handle operable to collapse and straighten the toggle to effect opening and closing movement, respectively, of the contact arm assemblies. The toggle linkage and movable handle are constructed in such a manner that the toggle tension springs will maintain the handle in the ON or closed circuit position without the aid of auxiliary devices whenever the circuit breaker contacts are welded closed regardless of whether the circuit breaker operating mechanism is latched or unlatched. To facilitate assembly and improve operation, one movable contact arm assembly is welded to the operating shaft and the remaining contact arm assemblies are mechanically fastened thereto and thereafter the subassembly is releasably journaled to stationary mounting brackets with fork-like retainer clips. Adjustable backup springs ensure maximum operating contact pressure of the contact arm assemblies on mating stationary contacts and minimize contact bounce and blow-open. A heat sink dissipates heat caused by overload currents within the circuit breaker and thereby prevents damage to the current-responsive elements. A counter weight attached to the trip lever prevents false release of the lever and opening of the breaker contacts due to external mechanical shocks and vibrations experienced by the breaker.
Inventors
- 👤 D Link
- 👤 F Williams
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 19:50
CPC Classifications
H; H01; H01H; H01H71/00; H01H71/10; H01H71/1054; H01H71/50; H01H71/501; H01H2071/1063; H01H71/1009; H01H71/12; H01H71/121; H01H71/504
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
168 words
In an electric circuit breaker, the combination with an insulating housing, stationary contact means in said housing, movable contact means and an operating mechanism in said housing for said movable contact means including an operating handle pivotally movable between ON and OFF positions, latch means movable between latched and unlatched positions, collapsible toggle linkage connected to said latch means and spring means connected between said latch means and said toggle linkage and movable by said handle over center of said linkage to actuate the latter between essentially collapsed and straightened positions to effect operation of said movable contact means between open and contact engaged positions with said stationary contact means, of second spring means normally out of engagement with said movable contact means and means responsive to movement of said toggle linkage to transmit the large operating force developed by said toggle linkage when it assumes a generally in-line position to said second spring means to provide corresponding contact closing force between said movable and stationary contact means.
Claim 2
Dependent Claim
168 words
In an electric circuit breaker, the combination with an insulating housing, stationary contact means in said housing, movable contact means and an operating mechanism in said housing for said movable contact means including an operating handle pivotally movable between ON and OFF positions, latch means movable between latched and unlatched positions, collapsible toggle linkage connected to said latch means and spring means connected between said latch means and said toggle linkage and movable by said handle over center of said linkage to actuate the latter between essentially collapsed and straightened positions to effect operation of said movable contact means between open and contact engaged positions with said stationary contact means, of second spring means normally out of engagement with said movable contact means and means responsive to movement of said toggle linkage to transmit the large operating force developed by said toggle linkage when it assumes a generally in-line position to said second spring means to provide corresponding contact closing force between said movable and stationary contact means.
Claim 3
Dependent Claim
57 words
An electric circuit breaker according to claim 1 wherein said movable contact means includes a contact carrier and a frame connected thereto and wherein said second spring means is connected to said frame and operable to engage said contact carrier and transmit the linkage operating force thereto just prior to said linkage assuming a generally in-line position.
Claim 4
Dependent Claim
78 words
An electric circuit breaker according to claim 1 wherein said breaker further includes an operating shaft responsive to said handle and connected to said movable contact means, wherein said breaker further includes a mounting bracket mounted in said housing having a bearing surface to receive said operating shaft, and wherein said breaker further includes a removable retainer means mountable on said mounting bracket to retain and journal said operating shaft on the bearing surface of said mounting bracket.
Claim 5
Dependent Claim
80 words
An electric circuit breaker according to claim 1 wherein said circuit breaker includes current responsive means operable to cause unlatching of said latch means to cause movement of said movable contacts into open circuit position in response to current overloads, said circuit breaker further including therein heat storage means operative to remove and store heat from said current responsive means caused by such overloads to prevent deflection or rupture thereof and subsequent loss of trip calibration with said latch means.
Claim 6
Dependent Claim
85 words
An electric circuit breaker according to claim 1 wherein said latch means includes a pivotally mounted latch member responsive to said current responsive means to unlatch said latCh means to cause opening of the circuit between said contacts and wherein said latch means further includes a counterweight means attachable to said pivotally mounted latch member to balance the inertial forces of mass about the pivot point of said member to ensure said member is not tripped by external vibration or shock to said circuit breaker.
Claim 7
Dependent Claim
47 words
An electric circuit breaker according to claim 1 wherein said circuit breaker further includes pressure plate means supportable within said housing and operable with said housing to position said current-responsive means thereagainst as a reference point for setting trip calibration between said current-responsive and said latch means.
Claim 8
Dependent Claim
108 words
An electric circuit breaker comprising, in combination: an insulating housing; stationary contact means mounted in said housing; movable contact means movable into and out of closed circuit with said stationary contact means; an operating shaft mounted within said housing supporting said movable contact means; an operating mechanism within said housing operable to move said movable contact means relative to said stationary contact means; a mounting bracket in said housing having partial bearing surfaces to receive said operating shaft; and removable retainer means mountable on said mounting bracket to complete the bearing surfaces for and retain and journal said operating shaft on the bearing surfaces of said mounting bracket.
Claim 9
Dependent Claim
108 words
An electric circuit breaker comprising, in combination: an insulating housing; stationary contact means mounted in said housing; movable contact means movable into and out of closed circuit with said stationary contact means; an operating shaft mounted within said housing supporting said movable contact means; an operating mechanism within said housing operable to move said movable contact means relative to said stationary contact means; a mounting bracket in said housing having partial bearing surfaces to receive said operating shaft; and removable retainer means mountable on said mounting bracket to complete the bearing surfaces for and retain and journal said operating shaft on the bearing surfaces of said mounting bracket.
Claim 10
Dependent Claim
109 words
An electric circuit breaker according to claim 7 wherein said operating mechanism includes a collapsible toggle linkage for operating one of said movable contacts and wherein said breaker further includes means responsive to said operating mechanism for initially biasing said movable contact means into contact with said stationary contact means spring means responsive to movement of said toggle linkage and operable to transmit the operating force of said linkage to said movable contact means when said toggle linkage assumes a generally in-line position thereby utilizing the large force generated at the end of the linkage movement to provide final contact closing pressure to said movable and stationary contact means.
Claim 11
Dependent Claim
37 words
An electric circuit breaker according to claim 7 wherein said stationary and movable contact means comprise a plurality of mating stationary and movable contacts and wherein one of said movable contacts is integral with said operating shaft.
Claim 12
Dependent Claim
117 words
An electric circuit breaker comprising in combination: an insulating housing; stationary contact means mounted within said housing movable contact means movable into and out of closed circuit with said stationary contacts; an operating mechanism within said housing including a collapsible toggle linkage for operating said movable contact means; and means including spring means normally out of engagement with said movable contact means and responsive to movement of said toggle linkage to transmit the operating force of said linkage to said movable contact means when said linkage assumes a generally in-line position thereby utilizing the large force generated at the end of the linkage movement to provide final contact closing pressure between said movable and stationary contact means.
Claim 13
Dependent Claim
117 words
An electric circuit breaker comprising in combination: an insulating housing; stationary contact means mounted within said housing movable contact means movable into and out of closed circuit with said stationary contacts; an operating mechanism within said housing including a collapsible toggle linkage for operating said movable contact means; and means including spring means normally out of engagement with said movable contact means and responsive to movement of said toggle linkage to transmit the operating force of said linkage to said movable contact means when said linkage assumes a generally in-line position thereby utilizing the large force generated at the end of the linkage movement to provide final contact closing pressure between said movable and stationary contact means.
Claim 14
Dependent Claim
62 words
An electric circuit breaker according to claim 10 wherein said movable contact means includes a frame and attached contact carrier and wherein said spring means is mounted on said frame and is operable to engage said carrier in line with said movable contact means and transmit the toggle linkage operating force thereto just prior to said linkage assuming a generally in-line position.
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) | 1977-11-18 | 1978-05-20 | 1978-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-11-18 | 1982-05-20 | 1982-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-11-18 | 1986-05-20 | 1986-11-19 | $7700.00 | Window Closed / Lapsed |