Patent ID: 6794595
Filing Date: 2004-09-21
Classification: H01H

Abstract:
An electrical switchgear apparatus, comprising:a case defining a longitudinal geometric reference plane and containing: an opening volume having an aperture ; and an arc extinguishing chamber communicating through the aperture with the opening volume and bounded by two opposite side walls parallel to the longitudinal geometric reference plane, a rear wall located opposite the aperture, a bottom wall and a top wall; a pair of separable contacts located in the opening volume and comprising a first movable contact movable along a flat path in the longitudinal geometric reference plane between a contact position and a separated position, and a second contact; a plurality of cooling fins located inside the arc extinguishing chamber and oriented perpendicular to the longitudinal geometric reference plane, each fin having a free edge for exposure to an arc; a bottom longitudinal electrode in electrical connection with the second contact, the bottom electrode at least partially covering the bottom wall of the arc extinguishing chamber; wherein: the free edges of the plurality of cooling fins collectively define a stack chamber extending in a direction from the bottom electrode to the top wall, the free edges defining the cross sectional shape of the stack chamber wherein the free edges of each fin include: a first tapered longitudinal portion communicating through the aperture with the opening volume, a second broadened longitudinal portion adjacent the rear wall, the second longitudinal portion having an oblong cross-section in a plane of cross-section parallel to the fins, a narrow intermediate portion joining the first longitudinal portion to the second longitudinal portion, wherein the stack chamber is also defined by the bottom electrode and the top wall.