# US 2014/0151206 A1 · Electrical switching apparatus and movable contact arm assembly therefor > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0151206 A1 - Document ID: US20140151206A1 - Status: Published application - Kind: A1 - Application number: 13/692,053 - Filed: 2012-12-03 - Published: 2014-06-05 - Earliest claimed: 2012-12-03 - Assignees: Eaton Corporation - Applicants: Eaton Corporation - Inventors: JAMES G. MALONEY; ROGER W. HELMS - Web page: https://patentgrep.com/patent/US20140151206A1 ## CPC - H01H 3/02: Operating parts, i.e. for operating driving mechanism by a mechanical force external to the switch - H01H 1/02: characterised by the material thereof {(containing gas-evolving material H01H33/765)} - H01H 1/22: with rigid pivoted member carrying the moving contact - H01H: ELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES (contact cables H01B7/10; electrolytic self-interrupters H01G9/18; emergency protective circuit arrangements H02H; switching by electronic means without contact-making H03K17/00) ## Abstract A movable contact arm assembly is provided for an electrical switching apparatus, such as a circuit breaker. The movable contact arm assembly includes a first member, and a second member attached to the first member. The first member is made from a first material, such as steel, and the second member is made from a second different material, such as copper. The first and second members each include first and second ends. The first end of the first member cooperates with the operating mechanism of the circuit breaker. The first end of the second member is attached to the second end of the first member. A movable contact is disposed on the second end of the second member. ## Claims ### Claim 1 A movable contact arm assembly for an electrical switching apparatus, said electrical switching apparatus including a housing, separable contacts enclosed by the housing, and an operating mechanism for opening and closing said separable contacts, said movable contact arm assembly comprising: a first member; and a second member attached to said first member, wherein said first member is made from a first material and said second member is made from a second different material. ### Claim 2 (depends on 1) The movable contact arm assembly of claim 1 wherein said first member and said second member combine to form a bimetallic movable contact arm. ### Claim 3 (depends on 2) The movable contact arm assembly of claim 2 wherein the first material of said first member is steel; and wherein the second material of the second member is copper. ### Claim 4 (depends on 1) The movable contact arm assembly of claim 1 wherein said separable contacts comprise a stationary contact and a movable contact; wherein said stationary contact is coupled to the housing of said electrical switching apparatus; and wherein said movable contact is structured to be disposed on said second member. ### Claim 5 (depends on 4) The movable contact arm assembly of claim 4 wherein said first member and said second member each include a first end and a second end; wherein the first end of said first member is structured to cooperate with said operating mechanism; wherein the first end of said second member is attached to the second end of said first member; and wherein said movable contact is structured to be disposed on the second end of the second member. ### Claim 6 (depends on 5) The movable contact arm assembly of claim 5 wherein the second end of said first member has a first shape; wherein the first end of said second member has a second shape; and wherein the first shape of said first member compliments the second shape of said second member. ### Claim 7 (depends on 6) The movable contact arm assembly of claim 6 wherein the second end of said first member comprises a recess; wherein the first end of said second member comprises a protrusion; and wherein said protrusion is disposed within said recess. ### Claim 8 (depends on 7) The movable contact arm assembly of claim 7 wherein the second end of said first member further comprises a first leg and a second leg disposed opposite the second leg; wherein said recess is formed between the first leg and the second leg; and wherein said protrusion is disposed within said recess between the first leg and the second leg. ### Claim 9 (depends on 8) The movable contact arm assembly of claim 8 wherein the first leg and the second leg are structured to be compressed against said protrusion to secure said second member to said first member. ### Claim 10 (depends on 1) The movable contact arm assembly of claim 1 wherein said electrical switching apparatus further includes a bimetal structure; wherein said second member further includes a flexible shut; and wherein said flexible shunt is structured to electrically connect said second member to said bimetal structure. ### Claim 11 An electrical switching apparatus comprising: a housing; separable contacts enclosed by the housing; an operating mechanism for opening and closing said separable contacts; and at least one movable contact arm assembly comprising: a first member, and a second member attached to said first member, wherein said first member is made from a first material and said second member is made from a second different material. ### Claim 12 (depends on 11) The electrical switching apparatus of claim 11 wherein said first member and said second member combine to form a bimetallic movable contact arm. ### Claim 13 (depends on 12) The electrical switching apparatus of claim 12 wherein the first material of said first member is steel; and wherein the second material of the second member is copper. ### Claim 14 (depends on 11) The electrical switching apparatus of claim 11 wherein said separable contacts comprise a stationary contact and a movable contact; wherein said stationary contact is coupled to the housing of said electrical switching apparatus; and wherein said movable contact is disposed on said second member. ### Claim 15 (depends on 14) The electrical switching apparatus of claim 14 wherein said first member and said second member each include a first end and a second end; wherein the first end of said first member cooperates with said operating mechanism; wherein the first end of said second member is attached to the second end of said first member; and wherein said movable contact is disposed on the second end of the second member. ### Claim 16 (depends on 15) The electrical switching apparatus of claim 15 wherein the second end of said first member has a first shape; wherein the first end of said second member has a second shape; and wherein the first shape of said first member compliments the second shape of said second member. ### Claim 17 (depends on 16) The electrical switching apparatus of claim 16 wherein the second end of said first member comprises a recess; wherein the first end of said second member comprises a protrusion; and wherein said protrusion is disposed within said recess. ### Claim 18 (depends on 17) The electrical switching apparatus of claim 17 wherein the second end of said first member further comprises a first leg and a second leg disposed opposite the second leg; wherein said recess is formed between the first leg and the second leg; and wherein said protrusion is disposed within said recess between the first leg and the second leg. ### Claim 19 (depends on 18) The electrical switching apparatus of claim 18 wherein the first leg and the second leg are compressed against said protrusion to secure said second member to said first member. ### Claim 20 (depends on 11) The electrical switching apparatus of claim 11 wherein said electrical switching apparatus is a circuit breaker; wherein said circuit breaker further includes a bimetal structure and a flexible shunt; and wherein said flexible shunt electrically connects said second member to said bimetal structure.