Patent ID: 6863256

Claim:
A valve assembly comprising: a housing having a flow channel and an annular surface surrounding the flow channel, the annular surface having a plurality of holes having axes extending parallel to an axis of the flow channel; a slide plate located in the housing and movable transversely to the axis of the flow channel between a closed position, in which the slide plate blocks flow through the flow channel, and an opened position, in which the slide plate allows flow through the flow channel; a seal ring positioned between the annular surface of the housing and the slide plate and coaxially surrounding the flow channel, the seal ring engaging the slide plate in the closed position thereof and disengaging the slide plate in the opened position thereof, wherein the seal ring has, on a side facing the annular surface of the housing, a plurality of circumferentially arranged bores aligned, respectively, with the holes formed in the adjacent annular surface of the housing, and wherein the bores each include an opening having a shape that is a complete circle include a side wall having an undercut forming a lip extending traverse to the side wall; and a plurality of fasteners displaceably arranged in the plurality of holes of the annular surface of the housing and extending into the plurality of bores, respectively, of the slide plate, wherein each of the fastener has side walls include slots, which receive the lips of the bores of the seal ring and secure the seal ring to the fasteners when the fasteners are inserted into the bores of the seal ring and the seal ring is rotated about the axis of the flow channel with respect to the annular surface of the housing, wherein the cross-sectional shape of the fasteners is circular and substantially corresponds to the circular openings of the bores.