Patent ID: 9064648
Filing Date: 2015-06-23
Classification: H01H

Abstract:
1. An outer wall of an arc extinguishing chamber, for resting on two rims of a housing of the case of a switchgear unit, said outer wall comprising an external rigid grate for closing off said housing, said grate comprising an intermediate part and an end part for resting on said rims and for protruding from the intermediate part into a space defined between said wall and said rims, a valve device coupled to the grate at the level of the intermediate part, including lips protruding from the intermediate part on at least two sides for resting on said rims, wherein said lips are heat-resistant insulating material having a strength such that each lip is substantially rigid and flat when said lip is subjected to an orthogonal pressure lower than a first threshold pressure, and said lip is deformable in reversible manner when the orthogonal pressure is greater than a second threshold pressure; and an internal frame and a filtering system housed between the internal frame and the external grate, the valve device for forming a tight gasket between said frame and said grate, wherein a cross-section of the wall forms a T-shape the branches of which are for resting on said rims, and wherein the lips are of such a size that an orthogonal pressure on said lips will close a space defined where the branches of said T approach a flat side of said housing.