Reversible four-way valve for reversible refrigerating cycle

摘要

Reversible four-way valve for the refrigerating system. It has a cylindrical valve body through which a single piston is adapted to reciprocate slidably. This single piston divides the cylindrical valve body into two chambers. One of the two chambers is used for admitting high pressure gas thereinto whereas the other is assigned for controlling the piston in counteracting the high pressure gas. For this purpose, the piston is formed with a pressure equalizing hole therein to communicate the two chambers with each other while the piston is urged toward the chamber into which the high pressure is admitted. This is done by a compression spring having a force stronger than required to overcome all resistance when both chambers are under the equal pressure. Since the reversible valve has only two chambers, compact design is possible and the operation is stable.