Back to results
US 4,274,445 AGranted
Pressure balanced three-way transfer valve
AssigneePall Corporation
InventorRoydon B. Cooper
Life of this patent
Estimating the term…
Abstract
A pressure-balanced three-way transfer valve for controlling fluid flow into one of two fluid lines includes a pair of cam actuated valves actuated by a single actuator to move a respective valve to an open and closed position. Pressure balancing of the valve rods is accomplished by a fluid passage through each of the respective rods to allow lower pressure to a respective balancing chamber. The valves further include respective balancing surfaces.
Claims8
A pressure-balanced three-way transfer valve for controlling fluid flow into one of two fluid lines, comprising, in combination:
- (1) a housing;
- (2) a valve chamber in the housing;
- (3) first, second and third fluid flow ports in the housing;
- (4) first, second and third fluid flow passages in the housing, intercommunicating the valve chamber with the first, second and third fluid flow ports;
- (5) a first valve member in the valve chamber movable between open and closed positions across the first fluid flow passage, and controlling flow through the first fluid flow port;
- (6) a second valve member in the valve chamber movable between open and closed positions across the second fluid flow passage, and controlling flow through the second fluid flow port;
- (7) first cam-following valve-actuating means in the valve chamber operatively connected to the first valve member;
- (8) second cam-following valve-actuating means in the valve chamber operatively connected to the second valve member;
- (9) a cam in the housing separated from the valve chamber and exposed to a pressure lower than fluid pressure;
- movable between first and second positions and operatively connected with the first and second cam-following valve-actuating means in a manner such that
- (a) with the cam in the first position, the first valve member is open and the second valve member is closed;
- (b) with the cam in the second position, the second valve member is open and the first valve member is closed;
- and
- (c) with the cam in intermediate positions, both the first and second valve members are open at least partially;
- (10) means for moving the cam between the first and second positions, thereby opening and closing the valves;
- (11) a first pressure-equalizing chamber defined by the first cam-following valve-actuating means and the first valve member;
- (12) a second pressure-equalizing chamber defined by the second cam-following valve-actuating means and the second valve member;
- (13) a first fluid passage through the first cam-following valve-actuating means intercommunicating the pressure lower than fluid pressure with the first pressure-equalizing chamber;
- (14) a second fluid passage through the second cam-following valve-actuating means intercommunicating the pressure lower than fluid pressure with the second pressure-equalizing chamber;
- (15) the first and second valve members each having pressure-receiving surfaces exposed to fluid pressure in the valve chamber and opposed pressure-receiving surfaces exposed to a pressure lower than fluid pressure in the pressure-equalizing chamber;
- (16) the first and second cam-following valve-actuating means each having pressure-receiving surfaces exposed to fluid pressure in the valve chamber and opposed pressure-receiving surfaces exposed to pressure lower than fluid pressure;
- and
- (17) the opposed pressure-receiving surfaces of the first and second valve members and first and second cam-following valve-actuating means being of such surface areas that the fluid pressure and lower pressure acting on the opposing pressure-receiving surfaces of the cam-following valve actuating means and valve members are substantially balanced;
- whereby such fluid pressures do not interfere with movement of the first and second valve members.
21 more elements
Dependencies are inferred from the claim text.