Electric circuit breaker

Claim 2

A movable contact arm assembly for an electric circuit breaker comprising a contact; an elongated composite contact carrier including a generally rectangular platelike current conducting blade having a bottom surface including a substantially flat face portion mounting said contact adjacent one end of the blade; an elongated structural support member having a longitudinal edge mounted in direct contact with the top surface of said blade, said support member being secured to the blade intermediate the ends thereof and including a pointed nose portion extending beyond the end of said blade mounting said contact; a contact operator pivotally mounting said carrier and including means for limiting pivotal movement of said carrier in a first pivotal direction and biasing means mounted on said operator for urging said carrier in said first pivotal direction to provide releasable engagement between said carrier and said limiting means.

Claim 3

In an electric switching device comprising a casing, a first contact mounted in said casing, a second contact in said casing having a surface adapted to engage a surface of said First contact, a movable contact arm assembly mounting said second contact for movement into and out of surface engagement with said first contact, and drive means moving said contact arm assembly toward and away from said first contact, the combination wherein the contact arm assembly includes a composite contact carrier comprising a platelike current conducting blade and a backing member for the blade in intimate supporting engagement therewith, said blade having a face portion disposed in confronting relationship to the first contact during surface engagement between said contacts; said blade being a generally rectangular strip having a bottom surface including said face portion, said second contact mounted on said face portion adjacent one end of said blade, the backing member having a longitudinal edge mounted in secured abutting relationship to said blade, and said backing member including an arc runner portion mounted adjacent said second contact.

Claim 4

In an electric switching device comprising a casing, a first contact mounted in said casing, a second contact in said casing having a surface adapted to engage a surface of said First contact, a movable contact arm assembly mounting said second contact for movement into and out of surface engagement with said first contact, and drive means moving said contact arm assembly toward and away from said first contact, the combination wherein the contact arm assembly includes a composite contact carrier comprising a platelike current conducting blade and a backing member for the blade in intimate supporting engagement therewith, said blade having a face portion disposed in confronting relationship to the first contact during surface engagement between said contacts; said blade being a generally rectangular strip having a bottom surface including said face portion, said second contact mounted on said face portion adjacent one end of said blade, the backing member having a longitudinal edge mounted in secured abutting relationship to said blade, and said backing member including an arc runner portion mounted adjacent said second contact.

Claim 5

A movable contact arm assembly for an electric circuit breaker comprising a contact, an elongated contact carrier including a platelike current conducting blade having a face portion mounting said contact and a structural support member secured to the blade, a contact operator mounting said carrier for limited movement in a first direction and biasing means operable against said support member for urging said carrier in said first direction, said blade being a generally rectangular strip having a bottom surface including said face portion, said contact mounted on said face portion adjacent one end of the blade, the support member having a longitudinal edge mounted in secured abutting relationship to said blade, the contact arm assembly including a contact operator mounting the carrier for limited movement in a first direction and biasing means associated with said operator for urging said carrier in said first direction.

Claim 6

A movable contact arm assembly for an electric circuit breaker comprising a contact, an elongated contact carrier including a platelike current conducting blade having a face portion mounting said contact and a structural support member secured to the blade, a contact operator mounting said carrier for limited movement in a first direction and biasing means operable against said support member for urging said carrier in said first direction, said blade being a generally rectangular strip having a bottom surface including said face portion, said contact mounted on said face portion adjacent one end of the blade, the support member having a longitudinal edge mounted in secured abutting relationship to said blade, the contact arm assembly including a contact operator mounting the carrier for limited movement in a first direction and biasing means associated with said operator for urging said carrier in said first direction.

Claim 7

In an electric switching device of the type comprising a casing, a normally stationary contact supported in said casing, a movable contact arm assembly supported in said casing and including a movable contact portion movable along a predetermined path into and out of engagement with said stationary contact, the combination wherein said movable contact arm assembly comprises: a. an elongated relatively wide, thin, flat current conducting member; b. a movable contact member rigidly and conductively mounted on a first wide surface of said current conducting member adjacent one end thereof; c. a backing member of relatively high strength material rigidly affixed to said current conducting member at a second wide surface thereof opposite said first wide surface, said backing member comprising a relatively wide, thin, flat member having its wide surfaces extending generally perpendicular to said wide surfaces of said current conducting member and having a longitudinal edge portion mounted in abutting relationship to said second wide surface of said current conducting member; and d. said contact arm assembly disposed in said casing with said first and second wide surfaces of said current conducting member extending substantially perpendicular to said predetermined path of movement of said movable contact member.

Claim 8

In an electric switching device of the type comprising a casing, a normally stationary contact supported in said casing, a movable contact arm assembly supported in said casing and including a movable contact portion movable along a predetermined path into and out of engagement with said stationary contact, the combination wherein said movable contact arm assembly comprises: a. an elongated relatively wide, thin, flat current conducting member; b. a movable contact member rigidly and conductively mounted on a first wide surface of said current conducting member adjacent one end thereof; c. a backing member of relatively high strength material rigidly affixed to said current conducting member at a second wide surface thereof opposite said first wide surface, said backing member comprising a relatively wide, thin, flat member having its wide surfaces extending generally perpendicular to said wide surfaces of said current conducting member and having a longitudinal edge portion mounted in abutting relationship to said second wide surface of said current conducting member; and d. said contact arm assembly disposed in said casing with said first and second wide surfaces of said current conducting member extending substantially perpendicular to said predetermined path of movement of said movable contact member.

Claim 9

The combination as set forth in claim 13 wherein: a. said current conducting member comprises a relatively high electrical conductivity metallic material; b. said backing member comprises a metallic material having an electrical conductivity substantially lower than that of said current conducting member; and c. said backing member further being composed of a material having a mechanical strength greater than that of said current conducting member.

Claim 10

The combination as set forth in claim 4 wherein: a. said current conducting member comprises copper; and b. said backing member comprises steel.

Claim 11

The combination as set forth in claim 4 wherein said backing member is disposed substantially along the longitudinal center line of said current Conducting member and is attached thereto by means of integral lug portions which extend through corresponding holes in said current conducting member.

Claim 12

The combination as set forth in claim 4 wherein said one end of said current conducting member is offset from the general plane of said current conducting member in a direction toward said first wide surface, and said backing member has its said longitudinal edge portion conforming to the contour of said offset at the portion abutting thereagainst.

Claim 13

The combination as set forth in claim 4 wherein said backing member has a nose portion extending beyond said current conducting member at said one end thereof and having a depending portion extending in the direction of said contact, said nose portion having a longitudinal edge portion extending substantially flush with the contacting face of said contact to provide an arc runner capable of readily accepting transfer of an arc from said contacting face of said contact.

Claim 14

The combination as set forth in claim 4 wherein said combination also comprises means supporting said contact arm assembly for pivotal movement in said casing between open and closed circuit positions with respect to said stationary contact, and flexible conductor means connected directly to said current conducting member of said contact arm assembly adjacent the end thereof opposite said one end whereby all current entering said current conducting member enters directly and without having to first pass through any portion of said backing member.