Four-way reversing valve

A four-way reversing valve comprising:

• a valve casing having a plurality of ports through which fluid flows;
• a valve main body fixedly installed to the valve casing and having a valve chamber in which a plurality of main port connection holes for selectively connecting the ports are formed;
• a main spool rotatably installed at the valve chamber of the valve main body, for selectively connecting the ports according to a rotation position;
• and
• a spool driving unit for reversibly rotating the main spool by using part of fluid supplied through one of the ports in the valve casing, wherein the valve main body further comprises a pilot hydraulic chamber which is formed by extending one side of the valve chamber and has two pilot input and output ports penetrating the pilot hydraulic chamber to alternately input and output the part of fluid in two opposite directions inside the valve casing and a pilot drain port for obtaining a pilot hydraulic pressure,
• the main spool further comprises a vane portion formed by extending one side of the main spool to be rotatable between the two pilot input and output ports in the pilot hydraulic chamber, and
• the spool driving unit comprises a solenoid for generating an electrical thrust by being excited by an electric signal, a plunger moved by the electrical thrust of the solenoid, a spring developing an elastic force to return the plunger in an opposite direction to the electrical thrust, and a pilot spool coupled to the plunger, and moving and returning together with the plunger and having a cavity for connecting one of the two pilot input and output ports and the drain port.

A four-way reversing valve comprising:

• a valve casing having a plurality of ports through which fluid flows;
• a valve main body fixedly installed to the valve casing and having a valve chamber in which a plurality of main port connection holes for selectively connecting the ports are formed;
• a main spool rotatably installed at the valve chamber of the valve main body, for selectively connecting the ports according to a rotation position;
• and
• a spool driving unit for reversibly rotating the main spool by using part of fluid supplied through one of the ports in the valve casing, wherein the hydraulic chamber of the valve main body is open to a wall surface and a bottom surface of the inner circumference of the valve casing, and the vane portion of the main spool rotates as the vane portion directly contacts the exposed wall surface and the bottom surface of the inner circumference of the valve casing and maintains sealing.