Rotary valve

摘要

A valve structure including a valve body defining a valve chamber, a pair of annular inlet and outlet seal members, and a tapered valve member journaled in corresponding tapered sealing surfaces in the inlet and outlet seal members. Passages communicate respectively between a fluid source and the inlet passage, the outlet passage and the valve chamber. The maximum diametral dimensions of the valve passage through the valve member at its point of communication with the tapered surface of the valve member is less than the minimum width of the sealing surfaces of the seal members along the path traced by the valve passage as the valve member is rotated. A method of controlling passage of material through such a valve structure is also disclosed.