Gate valve for use with vacuum equipment

Claim 1

A gate valve for use in conjunction with vacuum equipment, and the like, comprising: a housing having a pair of opposite walls with aligned orifices therein; a pair of annular valve seats mounted to surround respective ones of said orifices; a gate assembly mounted in said housing, said gate assembly including a carrier, and at least one gate mounted on the carrier; an actuator coupled to the carrier for reciprocally moving the gate assembly in a direction parallel to the opposite walls of the housing between a first position coaxial with said orifices and a second position displaced from said orifices; a sub-assembly including two open-ended electrically conductive cylindrical sections coaxially adjacent to one another and coupled to the carrier and movable to a position coaxial with said seats when the gate assembly is moved to the second position, resilient means mechanically coupled to the two cylindrical sections for biasing the two sections into respective engagement with corresponding ones of the valve seats when the gate assembly is moved to the second position, said sub-assembly including means interconnecting said section to provide a smooth electrically conductive bore surface between the orifices and said cylindrical sections for the free passage of radio frequency currents when the valve is open; and roller means coupled to the sub-assembly and engaging the inner surface of the housing as the gate assembly is moved by the carrier toward said second position to allow said sections to move toward one another away from said seats, the roller means being received in detents in the inner surface of the housing to permit the resilient means to bias the cylindrical sections into respective engagement with the valve seats when the sub-assembly is axially aligned with the orifices when said gate assembly is moved toward said first position.