Vacuum switching tube

摘要

Previously known vacuum switching tubes having two stationary contact elements and one moving contact element located between them and bridging them are not suitable for heavy currents and high voltages as a result of the geometric arrangement of their contact system, it also being necessary to exert a high contact force continuously on the moving contact element in the connected state, by means of an externally arranged drive, in order to avoid said contact element lifting off in the event of short-circuit currents, in the case of which event there is a risk of the contacts welding. In the case of a vacuum switching tube having a contact system (3) which is located in a housing (1) and consists of two stationary contact elements (6), which are opposite one another, and a moving contact element (8) which is located between them and bridges them, an electrical power supply in the form of a loop is formed by the V-shaped arrangement of the stationary contact elements (6), which are combined with high-voltage bushings (7) to form coaxial, vacuum-tight structural units (23), in the case of which power supply the current forces counteract the stationary contact element (8) lifting off, even in the case of heavy short-circuit currents, so that, overall, high voltages and heavy currents can be switched and, at the same time, the cost for mounting and driving the vacuum switching tube is only low. Vacuum switching tube for vacuum power switches (circuit breakers) in the medium-voltage range for conventional and compressed-gas-insulated medium-voltage switching installations. <IMAGE>