US3663903A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tripping system for circuit breaker
Assignee: ITE Imperial Corp
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Filing: 1971-05-20
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Granted: 1972-05-16
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Expires: 1991-05-20
Abstract
Abstract A current limiting circuit breaker is constructed to achieve more rapid tripping in the medium fault current range by utilizing a magnetic tripping device which imparts physical motion to the movable contact under particular fault current conditions. In the lowest fault current range above the thermal tripping range the magnetic tripping unit automatically operates or releases the spring operating mechanism thereby causing contact separation. As fault current increases the magnetic tripping means is effective to assist the operating mechanism to physically move the movable contact, and at still higher currents the magnetic tripping means moves the movable contact to its fully open position before any movement is imparted to the movable contact by the spring operating mechanism. As fault currents increase still further, electrodynamic forces assist the magnetic means to physically move the movable contacts, and in the very highest fault current range electrodynamic operation moves the movable contact essentially to its fully opened position, before the magnetic trip means for the operating mechanism is active in moving the movable contact.
Inventors
- 👤 Frank W Kussy
- 👤 Gustave E Heberlein Jr
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 18:01
CPC Classifications
H; H01; H01H; H01H71/00; H01H71/10; H01H71/12; H01H71/24; H01H71/2409; H01H77/00; H01H77/02; H01H77/10
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
225 words
A circuit interrupter including relatively stationary contact means; movable contact means; arm means having said movable contact means mounted thereto; a releasable operating mechanism connected to said arm means for moving the latter to operate said movable contact means into and out of engagement with said stationary contact means; said operating mechanism when released providing a spring force to separate said movable and stationary contact means; first means effective at fault currents above a first level through said interrupter to release said operating mechanism; second means effective at fault currents above a second level to exert a mechanical force on said movable contact means separating the latter from said stationary contact means; third means effective at fault currents above a third level to exert an electrodynamic force acting to separate said contact means; said second level being between said first and third levels; at fault currents in a first range immediately above said second level said spring force and said mechanical force supplementing each other to increase speed of contact means separation above the speed of contact means separation provided solely by said spring force; at fault currents in a second range immediately above said third level said electrodynamic force supplementing said mechanical force and increasing speed of contact means separation above that provided by the combination of said spring force and said mechanical force.
Claim 2
Dependent Claim
225 words
A circuit interrupter including relatively stationary contact means; movable contact means; arm means having said movable contact means mounted thereto; a releasable operating mechanism connected to said arm means for moving the latter to operate said movable contact means into and out of engagement with said stationary contact means; said operating mechanism when released providing a spring force to separate said movable and stationary contact means; first means effective at fault currents above a first level through said interrupter to release said operating mechanism; second means effective at fault currents above a second level to exert a mechanical force on said movable contact means separating the latter from said stationary contact means; third means effective at fault currents above a third level to exert an electrodynamic force acting to separate said contact means; said second level being between said first and third levels; at fault currents in a first range immediately above said second level said spring force and said mechanical force supplementing each other to increase speed of contact means separation above the speed of contact means separation provided solely by said spring force; at fault currents in a second range immediately above said third level said electrodynamic force supplementing said mechanical force and increasing speed of contact means separation above that provided by the combination of said spring force and said mechanical force.
Claim 3
Dependent Claim
51 words
A circuit interrupter as set forth in claim 1 in which there is a third range of currents, between said first range and said third level, in saId third range of currents movement of said movable contact means to its fully open position is due essentially solely to said mechanical force.
Claim 4
Dependent Claim
36 words
A circuit interrupter as set forth in claim 2 in which at currents above said second range, movement of said movable contact means to its fully open position is due essentially solely to said electrodynamic force.
Claim 5
Dependent Claim
50 words
A circuit interrupter as set forth in claim 1 in which initial contact means separation is the result of said mechanical force at fault currents between said second and third levels, and initial contact means separation is the result of said electrodynamic force at fault currents above said third level.
Claim 6
Dependent Claim
81 words
A circuit interrupter as set forth in claim 1 in which the third means includes first and second current path sections through which currents flow in opposite directions when said contact means are in engagement; said movable contact means including said first path section; said path sections being positioned in close proximity so that magnetic fluxes generated by said currents flowing in said path sections interact to produce a substantial portion of said electrodynamic force acting to separate said contact means.
Claim 7
Dependent Claim
27 words
A circuit interrupter as set forth in claim 5 in which the stationary contact means includes first and second spaced contacts bridged by said movable contact means.
Claim 8
Dependent Claim
45 words
A circuit interrupter as set forth in claim 6 in which said movable contact means also includes generally parallel arms at opposite ends of said first path section; a movable contact at the free end of each of said arms engageable with said stationary contacts.
Claim 9
Dependent Claim
28 words
A circuit interrupter as set forth in claim 7 in which the arms are generally L-shaped and are disposed in planes at right angles to said path sections.
Claim 10
Dependent Claim
29 words
A circuit interrupter as set forth in claim 1 in which the second means includes an electromagnet which generates said mechanical force at fault currents above said second level.
Claim 11
Dependent Claim
30 words
A circuit interrupter as set forth in claim 9 in which operation of the electromagnet is also effective to operate said first means at fault currents above said first level.
Claim 12
Dependent Claim
69 words
A circuit interrupter as set forth in claim 1 in which said arm means comprises a main arm and an auxiliary arm; said main arm being interposed between said auxiliary arm and said operating mechanism; said movable contact means mounted on said auxiliary arm; pivot means mounting said main arm near one end thereof; said auxiliary arm being movably mounted to said main arm near the other end thereof.
Claim 13
Dependent Claim
51 words
A circuit interrupter as set forth in claim 11 in which there is an overcenter spring connected to said auxiliary arm for biasing said auxiliary arm in opposite directions about said pivot means as the line of action for said overcenter spring is shifted to opposite sides of said pivot means.
Claim 14
Dependent Claim
45 words
A circuit interrupter as set forth in claim 11 in which the second means includes an electromagnet which generates said mechanical force at fault currents above said second level operable to move said auxiliary arm relative to said main arm in contact means opening direction.
Claim 15
Dependent Claim
43 words
A circuit interrupter as set forth in claim 13 in which the auxiliary arm is pivotally mounted to said main arm, and there is a spring device acting to pivot said auxiliary arm relative to said main arm in contact means closing direction.
Claim 16
Dependent Claim
81 words
A circuit interrupter as set forth in claim 14 in which the third means includes first and second current path sections through which currents flow in opposite directions when said contact means are in engagement; said movable contact means including said first path section; said path sections being positioned in close proximity so that magnetic fluxes generated by said currents flowing in said path sections interact to produce a substantial portion of said electrodynamic force acting to separate said contact means.
Claim 17
Dependent Claim
78 words
A circuit interrupter as set forth in claim 15 in which the stationary contact means includes first and Second spaced contacts bridged by said movable contact means; said moving contact means also including generally parallel arms at opposite ends of said first path section; a movable contact at the free end of each of said arms engageable with said stationary contacts; said arms being generally L-shaped and being disposed in planes at right angles to said path sections.
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) | 1975-05-16 | 1975-11-15 | 1976-05-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-16 | 1979-11-15 | 1980-05-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-16 | 1983-11-15 | 1984-05-16 | $7700.00 | Window Closed / Lapsed |