Multiple port fluid control device

Claim 1

A multiple port fluid control device comprising: a housing having a cylindrical chamber therein of uniform cross-sectional area and three ports communicating with said chamber, a first and second of said ports being spaced apart and the third of said ports being disposed between and spaced from said first and second ports, a valve stem slidably supported in said housing and having at least one portion extending out of said housing and designed for connection to a valve actuating device, and a flexible valve disc having a central portion fixedly secured to said valve stem intermediate the ends thereof in such a position that said valve stem is movable between a first position in which said valve disc is disposed between said first and third ports and a second position in which said valve disc is disposed between said second and third ports, said valve disc having an outer portion having a peripheral configuration of the same shape as the cross-sectional area of said chamber, the area of said valve disc being sufficiently larger than the crosssectional area of said chamber such that as said valve disc is slid along the interior of said chamber in seating engagement therewith, the outer portion thereof is flexed away from a plane transverse to said valve stem in a direction opposite to the direction of movement thereof, said valve disc being sufficiently small that the outer portion thereof is moved from one flexed position to an opposite flexed position as said valve stem is moved back and forth so that the outer portion of the disc is always directed towards said third port.