Vacuum slide valve

A vacuum valve comprising in combination, a first stationary metallic plate member, a second moveable plate member formed of an oil impregnated metallic substance lying on said first plate member, the contacting surfaces of said first and second plate members being smooth and flat, means for pivoting said moveable plate member at one end thereof to said stationary plate member, bores in said stationary plate member being provided with means for connection to a vacuum source and vacuum utilizing mechanism respectively, means providing a recess in said moveable plate member extending inwardly thereof from said contacting surface thereof, a cam follower roller mounted on said moveable plate member, cam wheel means mounted on said stationary plate member parallel to said moveable plate member for cooperating with said cam follower roller, spring means acting upon said moveable plate member to hold the cam follower roller against the outer surface of said cam wheel, said cam wheel being formed to slide said second plate member upon said first plate member between a first position and a second position and means providing a third bore extending through said moveable plate member, said first bore being located to be in fluid flow communication with said recess in both said first and second positions to maintain a vacuum in said recess at all times, said second bore being in communication with said recess in said first position to provide a vacuum at the vacuum utilizing mechanism and being in communication with said third bore in said second position to relieve the vacuum at the vacuum utilizing mechanism.