Contact arrangements for electrical disconnect switches

718,343. Air-break switches. KEARNEY CORPORATION. J. R. Oct. 29. 1952, No. 27191/52. Class 38(5) A disconnect switch has a switch blade 18 pivotally mounted at its lower end on a support so as to co-operate with fixed contacts 11, 14, the upper end of the blade carrying locking means movable longitudinally thereof to engage a fixed cam so as to increase the contact pressure: The locking means comprises a plunger 25 carrying a roller 27 co-operating with the cam face 9 and urged downwards by a spring 30. When the switch is closed, the spring 30 is restrained by an overset toggle comprising links 33, 37 connected respectively to the blade 18 and to plunger 25, the link 33 having an extension 35 having a loop 36 for engagement by an operating pole. The switch is opened by pulling the loop 36 downwards to break the toggle and then to swing the blade clockwise. It is reclosed by pushing the loop upwards to re-engage the contacts, further upward movement pushing the roller against cam face 9 and pushing the toggle over-centre. The blade 18 is of circular cross-section and co-operates with. sloping rib pads on contacts 11, 14. The mounting pin 24 of the blade is eccentrically mounted to adjust the blade position. The roller 27 is also eccentrically mounted for adjustment purposes. The movement of the toggle to the Fig. 1 position is limited by an adjustable stop 40 in the extension 35.