Abstract: A contact arm for a circuit breaker includes a body extending along a body axis between a first end and a second end. The body includes an interior surface, an exterior surface, and a fin extending between the interior surface and the exterior surface. The body defines a fin opening adjacent the fin. The fin opening extends between the interior surface and the exterior surface. The interior surface defines a substantially hollow interior. A body opening is located at the first end in fluid communication with the interior. Air flows through the body opening, into the interior, and from the interior out through the fin opening to reduce a temperature of the contact arm.

Abstract: A contact arm for a circuit breaker includes a body extending along a body axis between a first end and a second end. The body includes an interior surface, an exterior surface, and a fin extending between the interior surface and the exterior surface. The body defines a fin opening adjacent the fin. The fin opening extends between the interior surface and the exterior surface. The interior surface defines a substantially hollow interior. A body opening is located at the first end in fluid communication with the interior. Air flows through the body opening, into the interior, and from the interior out through the fin opening to reduce a temperature of the contact arm.

Abstract: A collector ring for transferring electrical current between a non-rotatable member and a rotatable member. The collector ring comprises a first support which is fixed to the non-rotatable member and which has at least one conductive metal ring member mounted thereon which is electrically insulated from the non-rotatable member. An input terminal is electrically connected to each of the ring members for connection to a source of electrical energy. A second support is rotatably mounted on the first support with the second support being adapted to operatively mechanically connected to the rotatable member whereby rotation of the rotatable member with respect to the non-rotatable member will cause the second support to rotate with respect to the first support.