Electricity: magnetically operated switches – magnets – and electr – Electromagnetically actuated switches – Automatic circuit-interrupting devices
Reexamination Certificate
1999-12-20
2001-02-06
Donovan, Lincoln (Department: 2832)
Electricity: magnetically operated switches, magnets, and electr
Electromagnetically actuated switches
Automatic circuit-interrupting devices
C218S022000
Reexamination Certificate
active
06184761
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to circuit breakers, and, more particularly, to circuit breakers having a rotary contact arm arrangement.
U.S. Pat. No. 4,616,198 entitled “Contact Arrangement for a Current Limiting Circuit Breaker” describes the early use of a first and second pair of circuit breaker contacts arranged in series to substantially reduce the amount of current let-through upon the occurrence of an overcurrent condition.
When the contact pairs are arranged upon one movable contact arm such as described within U.S. Pat. No. 4,910,485 entitled “Multiple Circuit Breaker with Double Break Rotary Contact”, some means must be provided to insure that the opposing contact pairs exhibit the same contact pressure to reduce contact wear and erosion.
One arrangement for providing uniform contact wear is described within U.S. Pat. 4,649,247 entitled “Contact Assembly for Low-voltage Circuit Breakers with a Two-Arm Contact Lever”. This arrangement includes an elongate slot formed perpendicular to the contact travel to provide uniform contact closure force on both pairs of contacts.
State of the art circuit breakers employing a rotary contact arrangement employ a rotor assembly and pair of powerful expansion springs to maintain contact between the rotor assembly and the rotary contact arm as well as to maintain good electrical connection between the contacts. The added compression forces provided by the powerful expansion springs must be overcome when the contacts become separated by the so-called “popping force” of magnetic repulsion that occurs upon over-current conditions to momentarily separate the circuit breaker contacts within the protected circuit before the circuit breaker operating mechanism has time to respond. The thickness of the moveable contact arm as well as the size of the contact springs has heretofore been increased to proportionately increase the overcurrent level at which the popping force causes the contacts to become separated. However, increased thickness and size decreases contact arm mobility and increases the cost.
SUMMARY OF THE INVENTION
In an exemplary embodiment of the invention, a movable contact arm arrangement for rotary contact circuit breakers comprises a movable contact arm having a central pivot point adapted to be pivotally connected within a circuit breaker interior. A first movable contact is arranged at first end of the contact arm and a second movable contact is arranged at a second end of the contact arm. A line strap arranged at the first end of the contact arm has first end portion with a first fixed contact connected thereto and arranged opposite the first movable contact. A second end portion of the line strap is adapted for connection within an electric circuit. The line strap has a hook-shaped configuration so that an outer face of the first fixed contact faces away from the central pivot point of the contact arm and is further arranged at a non-zero degree angle relative to the second end portion of the line strap.
REFERENCES:
patent: D. 367265 (1996-02-01), Yamagata et al.
patent: 2340682 (1944-02-01), Powell
patent: 2719203 (1955-09-01), Gelzheiser et al.
patent: 2937254 (1960-05-01), Ericson
patent: 3158717 (1964-11-01), Jencks et al.
patent: 3162739 (1964-12-01), Klein et al.
patent: 3197582 (1965-07-01), Norden
patent: 3307002 (1967-02-01), Cooper
patent: 3517356 (1970-06-01), Hanafusa
patent: 3631369 (1971-12-01), Menocal
patent: 3803455 (1974-04-01), Willard
patent: 3883781 (1975-05-01), Cotton
patent: 4129762 (1978-12-01), Bruchet
patent: 4144513 (1979-03-01), Shafer et al.
patent: 4158119 (1979-06-01), Krakik
patent: 4165453 (1979-08-01), Hennemann
patent: 4166988 (1979-09-01), Ciarcia et al.
patent: 4220934 (1980-09-01), Wafer et al.
patent: 4255732 (1981-03-01), Wafer et al.
patent: 4259651 (1981-03-01), Yamat
patent: 4263492 (1981-04-01), Maier et al.
patent: 4276527 (1981-06-01), Gerbert-Gaillard et al.
patent: 4297663 (1981-10-01), Seymour et al.
patent: 4301342 (1981-11-01), Castonguay et al.
patent: 4360852 (1982-11-01), Gilmore
patent: 4368444 (1983-01-01), Preuss et al.
patent: 4375021 (1983-02-01), Pardini et al.
patent: 4375022 (1983-02-01), Daussin et al.
patent: 4376270 (1983-03-01), Staffen
patent: 4383146 (1983-05-01), Bur
patent: 4392036 (1983-07-01), Troebel et al.
patent: 4393283 (1983-07-01), Masuda
patent: 4401872 (1983-08-01), Boichot-Castagne et al.
patent: 4409573 (1983-10-01), DiMarco et al.
patent: 4435690 (1984-03-01), Link et al.
patent: 4467297 (1984-08-01), Boichot-Castagne et al.
patent: 4468645 (1984-08-01), Gerbert-Gaillard et al.
patent: 4470027 (1984-09-01), Link et al.
patent: 4479143 (1984-10-01), Watanabe et al.
patent: 4488133 (1984-12-01), McClellan et al.
patent: 4492941 (1985-01-01), Nagel
patent: 4541032 (1985-09-01), Schwab
patent: 4546224 (1985-10-01), Mostosi
patent: 4550360 (1985-10-01), Dougherty
patent: 4562419 (1985-12-01), Preuss et al.
patent: 4589052 (1986-05-01), Dougherty
patent: 4595812 (1986-06-01), Tamaru et al.
patent: 4611187 (1986-09-01), Banfi
patent: 4612430 (1986-09-01), Sloan et al.
patent: 4616198 (1986-10-01), Pardini et al.
patent: 4622444 (1986-11-01), Kandatsu et al.
patent: 4631625 (1986-12-01), Alexander et al.
patent: 4642431 (1987-02-01), Tedesco et al.
patent: 4644438 (1987-02-01), Puccinelli et al.
patent: 4649247 (1987-03-01), Preuss et al.
patent: 4658322 (1987-04-01), Rivera
patent: 4672501 (1987-06-01), Bilac et al.
patent: 4675481 (1987-06-01), Markowski et al.
patent: 4682264 (1987-07-01), Demeyer
patent: 4689712 (1987-08-01), Demeyer
patent: 4694373 (1987-09-01), Demeyer
patent: 4710845 (1987-12-01), Demeyer
patent: 4717985 (1988-01-01), Demeyer
patent: 4733211 (1988-03-01), Castonguay et al.
patent: 4733321 (1988-03-01), Lindeperg
patent: 4764650 (1988-08-01), Bur et al.
patent: 4768007 (1988-08-01), Mertz et al.
patent: 4780786 (1988-10-01), Weynachter et al.
patent: 4831221 (1989-05-01), Yu et al.
patent: 4870531 (1989-09-01), Danek
patent: 4883931 (1989-11-01), Batteux et al.
patent: 4884047 (1989-11-01), Baginski et al.
patent: 4884164 (1989-11-01), Dziura et al.
patent: 4900882 (1990-02-01), Bernard et al.
patent: 4910485 (1990-03-01), Bolongeat-Mobleu et al.
patent: 4914541 (1990-04-01), Tripodi et al.
patent: 4916420 (1990-04-01), Bartolo et al.
patent: 4916421 (1990-04-01), Pardini et al.
patent: 4926282 (1990-05-01), McGhie
patent: 4935590 (1990-06-01), Malkin et al.
patent: 4937706 (1990-06-01), Schueller et al.
patent: 4939492 (1990-07-01), Raso et al.
patent: 4943691 (1990-07-01), Mertz et al.
patent: 4943888 (1990-07-01), Jacob et al.
patent: 4950855 (1990-08-01), Bolonegeat-Mobleu et al.
patent: 4951019 (1990-08-01), Gula
patent: 4952897 (1990-08-01), Barnel et al.
patent: 4958135 (1990-09-01), Baginski et al.
patent: 4965543 (1990-10-01), Batteux
patent: 4983788 (1991-01-01), Pardini
patent: 5001313 (1991-03-01), Leclerq et al.
patent: 5004878 (1991-04-01), Seymour et al.
patent: 5029301 (1991-07-01), Nebon et al.
patent: 5030804 (1991-07-01), Abri
patent: 5057655 (1991-10-01), Kersusan et al.
patent: 5077627 (1991-12-01), Fraisse
patent: 5083081 (1992-01-01), Barrault et al.
patent: 5095183 (1992-03-01), Raphard et al.
patent: 5103198 (1992-04-01), Morel et al.
patent: 5115371 (1992-05-01), Tripodi
patent: 5120921 (1992-06-01), DiMarco et al.
patent: 5132865 (1992-07-01), Mertz et al.
patent: 5138121 (1992-08-01), Streich et al.
patent: 5140115 (1992-08-01), Morris
patent: 5153802 (1992-10-01), Mertz et al.
patent: 5155315 (1992-10-01), Malkin et al.
patent: 5166483 (1992-11-01), Kersusan et al.
patent: 5172087 (1992-12-01), Castonguay et al.
patent: 5178504 (1993-01-01), Falchi
patent: 5184717 (1993-02-01), Chou et al.
patent: 5187339 (1993-02-01), Lissandrin
patent: 5198956 (1993-03-01), Dvorak
patent: 5200724 (1993-04-01), Gula et al.
patent: 5210385 (1993-05-01), Morel et al.
patent: 5239150 (1993-08-01), Bolongeat-Mobleu et al.
patent: 5260533 (1993-11-01), Livesey et al.
patent: 5262744 (1993-11-01), Arnold et al.
patent: 5280144 (1994-01-01), Bolongeat-Mobleu et al.
patent: 5281776 (1994-01-01),
Arnold David
Doma Palani Krishnan
Schlitz Daniel
Cantor & Colburn LLP
Donovan Lincoln
General Electric Company
Horton Carl B.
LandOfFree
Circuit breaker rotary contact arrangement does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Circuit breaker rotary contact arrangement, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Circuit breaker rotary contact arrangement will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2578020