[54] CURRENT LIMITING CIRCUIT
INTERRUPTER WITH IMPROVED
OPERATING MECHANISM
[75] Inventor: Miguel B. Yamat, Greendale, Wis.
[73] Assignee: Westinghouse Electric Corp., Pittsburgh, Pa.
[21] Appl. No.: 951,939
[22] Filed: Oct. 16, 1978
[51] Int. CI.1 H01H 75/12; H01H 9/20
[52] U.S. CI 335/16; 335/170;
335/171; 335/195
[58] Field of Search 335/15, 16, 21, 22,
335/167, 168, 169, 170, 171, 172, 173, 174, 195
[56] References Cited
U.S. PATENT DOCUMENTS
3.343.108 9/1967 Murai 335/16
3.469,216 9/1969 Shiraishi 335/16 X
3.663.903 5/1972 Kussy el al 335/16
FOREIGN PATENT DOCUMENTS
1193222 5/1970 United Kingdom .
1214363 12/1970 United Kingdom .
Primary Examiner—Fred L. Braun
Attorney, Agent, or Firm—Robert E. Converse, Jr.
[57] ABSTRACT
A current limiting circuit interrupter includes two parallel pivoting contact arms carrying contacts at the ends thereof. The upper contact arm is pivoted upon a carriage which is in turn pivotally mounted upon a mechanism frame. A latch rod is movably secured in arcuate slots in the sides of the mechanism frame. When the circuit interrupter is in the closed circuit position, a pair of springs connected between the latch rod and the carriage urges the latch rod against a reaction surface of the upper contact arm to provide contact closing pressure. Upon occurrence of severe overload current conditions, the upper contact arm pivots upon the carriage, moving the latch rod within the arcuate slots to release the contact closing pressure, allowing the springs to move the latch rod against a latching surface of the upper contact arm to latch the upper contact arm in the open circuit position.
14 Claims, 5 Drawing Figures
