Eccentric, sealless, rotary valve for flow control

Claim 1

In a rotary-type control valve, the combination of a housing defining a valve chamber having an inlet port and an outlet port for fluid flow therethrough to be controlled; an internal valve seat formed at one of said ports, said valve seat having a longitudinal flow axis A-A, said seat flow axis A-A extending centrally of the longitudinal lines of flow through said valve seat; valve member mounting and rotating means in said chamber intermediate said ports, said valve member mounting and rotating means arranged on a transverse axis B-B in a plane normal to said valve seat flow axis A-A, said transverse valve member mounting and rotating means having its transverse axis B-B within said longitudinal lines of flow through, and offset from said centrally longitudinally extending axis A-A of, said valve seat; and a hub rigidly non rotatably received on said valve member mounting and rotating means, a rigid head having a face formed for fluid-sealing engagement with said internal valve seat, and intermediate means supporting and spacing said head from said hub; said hub, intermediate means and head of said valve member being generally of rigid, unitary, hard metal construction, said intermediate means formed also with a predetermined elastic modulus in the direction of valve movement permitting its repeated slight flexing in the port opening-closing manipulation of the valve member, said valve member having an axis C-C centrally through said head, through the center D of said head face, and offset from said transverse rotation axis B-B said valve member constructed and arranged also for initial, point engagement of said valve head to said valve seat with said member axis C-C on the opposite side of said seat flow axis A-A from said rotation axis B-B, said valve member having a fulcrum arm B-D defined between said rotation axis B-B and said valve head center D said fulcrum arm B-D inclined towards said seat at a substantially greater than 90 degree angle to said seat flow axis A -A, whereby, in the continued actuation of said valve rotating means to fully close said valve, said fulcrum arm B-D is advanced to bring said valve head center D into coincidence with said seat axis A-A, and said intermediate means is thereby subjected to a large axial component of force sufficient to flex said intermediate means and pivot said head on said point until said valve head face is brought into full circumferential engagement against said seat.