Valve slide plate

Claim 1

In a valve including a housing having a fixed valve base plate defining inlet ports for first and second liquids and an outlet port for mixed liquids, a valve slide plate of ceramic oxide material or the like located in said housing and having opposite faces one of which is in sliding contact with a surface of said valve base plate, said valve slide plate being provided with an interior overflow passage extending entirely therethrough from said one face to the other face of said valve slide plate and adapted to communicate with said inlet and outlet ports, and a movable driver element in said housing, said valve slide plate being connected to said driver element for joint movement therewith; the improvement comprising that: (a) said driver element includes a plate-shaped member having a surface juxtaposed to said other face of said valve slide plate, said plate-shaped member carrying said valve slide plate; and (b) a flexible vulcanized seal member is interposed between said other face of said valve slide plate and said surface of said plate-shaped member, said seal member being vulcanized to said valve slide plate at said other face of the latter around the periphery of said overflow passage and being in engagement with said surface of said plate-shaped member to provide a seal between said drive element and said valve slide plate, said seal member being formed to engage said plate-shaped member with only a minimal contact pressure determined by the prevailing liquid pressure.