Abstract: An apparatus for a gate valve between chambers includes a valve housing defining a flow path. A male valve portion is rotatable on a fixed axis in the housing. The male valve portion including a first male mating surface positioned at a first angle less than perpendicular to the axis. A female valve portion is fixed in the valve housing for receiving the male portion. The female valve portion including a first female mating surface positioned at a second angle matching the first angle. An o-ring seals the male valve portion to the female valve portion when the male valve portion is rotated into the female valve portion. A polished surface contacts the o-ring when the male valve portion is rotated. When the male valve portion is rotated into the female valve portion the o-ring is compressed thereby sealing the gate valve and closing the flow path.

Abstract: The invention is a dual spreading link mechanism for application with gate valves. The invention also extends to gate valves employing the inventive dual spreading link. In one application to pendulum gate valves, a valve carriage assembly moves in a pendular manner within a gate valve housing and operates to seal off the flow channel of the housing. The valve carriage assembly is comprised of a valve plate having a valve seat face for engaging with the housing in a sealing manner, a tensioning member which along with a plurality of clip springs provides a contracting force to the valve carriage assembly, and an actuating member which moves laterally within the carriage assembly to alternately spread and contract the assembly. The actuating member is stacked between the valve plate and tensioning member and the actuating member is coupled to the valve plate and tensioning member by a plurality of oblong rotatable links which comprise the dual spreading link.

Abstract: An apparatus for a gate valve between chambers includes a valve housing defining a flow path. A male valve portion is rotatable on a fixed axis in the housing. The male valve portion including a first male mating surface positioned at a first angle less than perpendicular to the axis. A female valve portion is fixed in the valve housing for receiving the male portion. The female valve portion including a first female mating surface positioned at a second angle matching the first angle. An o-ring seals the male valve portion to the female valve portion when the male valve portion is rotated into the female valve portion. A polished surface contacts the o-ring when the male valve portion is rotated. When the male valve portion is rotated into the female valve portion the o-ring is compressed thereby sealing the gate valve and closing the flow path.