Axial valve for controlling the differential pressure between a delivery branch and a return branch of a hydraulic circuit

An axial differential pressure control valve (DPCV) for controlling the differential pressure between branches of a hydraulic circuit, the DPCV comprising:

• an axial inlet for receiving a return fluid at a first pressure, the return fluid being supplied from a return branch of the hydraulic circuit;
• a radial inlet for receiving a delivery fluid at a second pressure, the delivery fluid being supplied from a delivery branch of the hydraulic circuit;
• an axial outlet connected to the hydraulic circuit for egress of a fluid at a third compensated pressure;
• an annular body;
• a tubular body coaxially inside the annular body, the tubular body having a first end for receiving the return fluid via the axial input, the first end also has an annular disk;
• an abutment flange adjacent a second end of the tubular body;
• a spring coaxially arranged outside of the tubular body and axially kept in position by extending between the annular disk and the abutment flange;
• a pipefitting for connection to the hydraulic circuit;
• a coaxial closing member for closing an outlet aperture formed in the second end of the tubular member, the outlet aperture for egress of the fluid from the tubular body, the coaxial closing member being fixed between the tubular body and the pipefitting;
• a locking ring nut screwed on an external thread of the pipefitting to sealingly close the pipefitting;
• a first chamber in fluid-dynamic communication with the axial inlet;
• a second chamber in fluid-dynamic communication with the radial inlet;
• and
• sealing separation means arranged between said first chamber and said second chamber, said separation means being movable axially upon activation of a combination thrust resulting from a pressure differential ΔP=P1−P2 and a force from the spring.

An axial differential pressure control valve (DPCV) for controlling the differential pressure between a return branch and a delivery branch of a hydraulic circuit, the DPCV comprising:

• a closing body defining:
• an axial inlet for ingress of return fluid supplied from the return branch at a return pressure;
• a radial inlet for ingress of delivery fluid supplied from the delivery branch at a delivery pressure;
• and defining an outer chamber designed to be filled with the delivery fluid at the delivery pressure;
• a first pipefitting defining an axial outlet for egress of exit fluid into the hydraulic circuit at a third compensated pressure;
• an annular body coupled to the first pipefitting and defining an inner chamber in fluid communication with the inlet for receiving the return fluid;
• a tubular body having an inlet end that forms an annular disk and an opposing outlet end, the tubular body being coaxially mounted inside the annular body so that the inlet end faces the axial inlet for ingress of the return fluid;
• an abutment flange surrounding the tubular body and housed inside the annular body opposing the annular disk;
• a spring coaxially arranged around the tubular body and extending between the annular disk and the abutment flange for applying a first force against the annular disk;
• a valve seat that selectively mates with the outlet end of the tubular body for closing fluid flow thru the tubular body;
• a membrane between the return chamber and the delivery chamber, the membrane moving axially based upon a thrust due to a pressure differential between the return pressure and the delivery pressure;
• a ring nut moveably coupled to the first pipefitting;
• and
• pins axially arranged between the ring nut and the abutment flange, wherein the pins contact with the abutment flange and are selectively moved axially upon axial movement of the ring nut independently of the fixed closing member so as to vary compression of the spring and, in turn, vary force against the annular disk to counteract the thrust.