Patent ID: 7138899

Claim:
A fuse element including a fusible conductor, which extends within a gas filled cavity in a cylindrical tube comprising an electrical insulator between two end faces of the tube, two end caps of an electrically conductive material being applied to the two ends of the tube such that an electrical contact is provided with the fusible conductor, wherein at least one respective elastic sealing element is inserted at at least one of the two ends in a space between a cap base and the end face of the tube and/or into a portion of the cavity of the tube adjacent to the end face such that one or more pressure balancing passages remain between the gas filled cavity within the tube and the external surroundings of the fuse element of such small cross-section that changes in pressure in the cavity are balanced only very slowly so that a sudden increase in pressure in the cavity, as occurs as a result of an arc, which is produced when the fusible conductor ruptures, can act to quench the arc wherein the time constant of the decomposition of sudden changes in the differential pressure between the cavity and the external surroundings is of the order of between 10 −2 to 10 2 seconds.