US 4,228,988 A · Valve

Abstract

A valve including annular valve seats, made of a resilient material such as rubber, fitted in respective valve seat retainers provided in the peripheral portions of fluid passages in the valve body. A gate is slidingly moved to open or close the valve, with its wall surface being maintained in contact with each valve seat. Each of said annular valve seats are brought into close contact with the wall of the gate when the gate is moved to a closed position to provide sealing therebetween. In addition, the valve comprises a fluid passage provided in the gate which serves to decrease the pressure of the fluid acting on the valve seat on the upstream side at the initial stage of the movement of the gate from the closed position to the open position, whereby the valve seat is biased from the gate.

Claims4

Dependent claims

A gate valve which comprises:

a resilient seat which is circular in cross section;
a retainer housing within which said resilient seat is disposed, said housing comprising a first member and a second member connected to said first member forming an open ended chamber therebetween wherein said first member includes an upper edge portion and said second member includes a lower edge portion, such that said upper and lower edge portions cooperate to retain said resilient seat;
gate means cooperatively engageable with said resilient seat;
and
passage means formed in said gate means and in said first member for communicating fluid flowing from said chamber out of said passage means.

2 more elements

Dependencies are inferred from the claim text.

Valve

Life of this patent

Valve

Life of this patent

Abstract

Claims4