Heat dissipating means for circuit-breaker and circuit-breaker with such a heat dissipating means

Patent, 2012

The present invention discloses a circuit breaker comprising: a vacuum chamber; a fixed contact and a movable contact disposed in a 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; a second electrical conductor coupled to said movable contact stem; at least one heat dissipating means disposed 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; a plurality of fins provided on said internal surface constitute a passage through which air is convected in a direction parallel to that of reciprocal movement of movable contact stem.