A valve assembly for a tire pressure management system includes a housing. A first chamber (32) is provided in the housing. A second chamber (38) is provided in the housing. The second chamber is selectively in fluid communication with the first chamber. A third chamber (44) is provided in the housing. The third chamber is selectively in fluid communication with the second chamber. A deflate piston (120) is at least partially provided in the third chamber and the second chamber. The deflate piston (120) selectively permits or prevents fluid communication between the second chamber and the third chamber. An inflate piston (72) is attached to the deflate piston (120). The inflate piston (72) is at least partially provided in the second chamber and the first chamber. The inflate piston (72) selectively permits or prevents fluid communication between the first chamber and the second chamber. At a first pressure, the second chamber is in direct fluid communication with the first chamber and, at a second pressure, the second chamber is in direct fluid communication with the third chamber. The second pressure is greater than the first pressure and the first pressure is greater than an initial pressure.

The invention discloses a hydraulic control system of a leveling hydraulic cylinder of a loading head, characterized by comprising a hydraulic pump, a two-position three-way electronic control reversing valve, a three-position four-way electronic control reversing valve, a three-position four-way cam valve and a hydraulic cylinder. The invention not only can perform leveling by using the electric control system, but also comprises the hydraulic cam valve controlling the hydraulic cylinder for self-leveling, and the two leveling manners can be independently used or switched mutually, thus achieving a better leveling effect.

A convenient switching valve includes a main body, a switching member and a positioning disc. The main body is provided with a water inlet and at least one water outlet. The positioning disc is rotatably fitted at an end of the main body. The positioning disc cooperates with the switching member, enabling the switching member to be moved in the main body to block a water passage between the water inlet and the water outlet. By rotating the positioning disc, the positioning disc movably press the switching member to block the water passage, thereby realizing the control of the water flow of the water outlet. The operation is convenient and labor-saving.

A three-way valve of a piston valve seal structure includes a valve box, a valve stem, and a valve body. The valve stem is a metallic rod-shaped member that reciprocates up and down in a piston structure. In the valve body, an upper guide washer is provided on the valve stem adjacent to an upper disc ring. An outer diameter of a portion of the upper guide washer is slightly smaller than an inner diameter of a flat portion of a first valve seat. A lower guide washer is provided on the valve stem adjacent to a lower disc ring. An outer diameter of a portion of the lower guide washer is slightly smaller than an inner diameter of a flat portion of the second valve seat.

A valve system for use with a cylinder having an extensible rod, includes first and second valve assemblies, each including an inlet/outlet port configured to selectively be coupled with a source of pressurized gas, a check valve biased toward a closed state and having a check valve body at least partially receivable within a first port of the cylinder, a flow control valve positioned in series between the inlet/outlet port and the check valve, and an inlet pilot port connected with the check valve for opening the check valve when supplied with pressurized gas. First and second pilot lines extend to the respective inlet pilot ports from respective outlet pilot ports of the opposite ones of the first and second valve assemblies. When pressurized gas is supplied to the inlet/outlet port of a valve assembly, pressurized gas is also supplied to the opposite inlet pilot port.

A thermal system includes a Rankine cycle heat recovery device including a Rankine circuit having a first heat exchanger, an expander, a condenser, and a first pump. A cooling device having a cooling circuit that includes a second heat exchanger, a second pump, and a third heat exchanger with a device to be cooled. The thermal system comprises a device for regulating the pressure in the Rankine circuit and includes an enclosure delimiting a space and housing a movable part separating the space into first and second chambers. The first chamber communicates with the Rankine circuit and the second chamber communicates with the cooling circuit.

A pilot valve controlled mechanical shut-down valve. The mechanical shut-down valve includes a thermostatic motor that effectuates closing of the pilot valve when the temperature of fluid flowing through the shut-down valve is one of greater than a predetermined value, less than a predetermined value, or within a range of predetermined values. As a result thereof, flow through the shut-down valve is stopped.

A hydraulic steering unit is described comprising a housing (1) and a non-return valve (2) having a ball (3) and a valve seat (4) at an end of a channel (5) in the housing (1), wherein a movement of the ball (3) away from the valve seat (4) is limited by an abutment (7) in the channel (5). Such a steering unit should have a non-return valve which can be produced with low costs. To this end the abutment (7) extends transversely through the channel.

A returnless fuel supply system applicable to an LPG vehicle is provided. The system supplies LPG fuel from an LPG bombe to an engine at a predetermined pressure or greater and prevents the generation of vapor in the LPG fuel, thereby eliminating a need to return a portion of the LPG fuel supplied to the engine to the LPG bombe. Through the application of the returnless fuel supply system that does not return the high temperature fuel to the LPG bombe, the cause of the internal pressure increase in the LPG bombe is eliminated, and thus efficient refueling of LPG bombe with LPG fuel is achieved.

Disclosed herein are systems comprising a pressure adjustment manifold, a pressure distribution manifold, and an electronic board, each of which are operatively connected. Also provided herein are methods of making and using the same.