CONTACT SYSTEM OF VACUUM ARC CHUTE ( VARIANTS ) Russian patent published in 2002 - IPC

FIELD: electrical engineering, heavy-current electric switches. SUBSTANCE: it is suggested that working surface of one of contacts of contact system of vacuum arc chute should have convex shape and working surface of another contact should have concave shape. Ratio h/r should be kept in limits 0.15-0.95, where r and h are correspondingly radius of base and height of working surface of each contact. Working surfaces of both contacts should include contact areas which lines of crossing with plane passing through axis of contact system should have same curvature radii. Boundaries of contact areas are determined by selection of radii of internal and external circumferences. EFFECT: enhanced switching off capacity of contact system without growth of its diameter and consequently of ohmic resistance, reduced required contact pressure by imparting special shape to working surfaces of contact straps. 3 cl, 15 dwg