Patent ID: 8278582

Claim:
A circuit breaker, comprising: a vacuum chamber; a fixed contact and a movable contact disposed in said vacuum chamber; a fixed contact stem supporting said fixed contact in said vacuum chamber and extending outwards from a first end of said vacuum chamber; a movable contact stem supporting said movable contact in said vacuum chamber for reciprocal movement between contact with and separated from said fixed contact, and extending outwards from a second end of said vacuum chamber; a first electrical conductor coupled to said fixed contact stem, wherein the first electrical conductor is coupled to the fixed contact stem at a first conjunction; a second electrical conductor coupled to said movable contact stem, wherein the second electrical conductor is coupled to the movable contact stem at a second junction; and at least one heat dissipating means provided for at least one of said fixed contact and movable contact, wherein the heat dissipating means is hollow and has an external surface and internal surface, and the internal surface has at least three fins separated from each other in a direction of air convection, wherein the heat dissipating means is coupled to at least one of the first junction and second junction, and wherein the at least one heat dissipating means includes a first wall, a second wall and a third wall, wherein the first wall and the second wall are parallel to each other and extend respectively from two edges of the third wall in a same direction generally perpendicular to the third wall.