Patent ID: 8733391
Filing Date: 2014-05-27
Classification: F15B,F16K,Y10T

Abstract:
1. A pressure control valve comprising: a sleeve having an inlet port formed thereon to receive hydraulic fluid from a hydraulic pump and a hydraulic tank flow path formed thereon to communicate with a hydraulic tank; a poppet slidably coupled in the sleeve to open/close a flow path between the inlet port and the hydraulic tank flow path; a poppet spring elastically supporting the flow path between the inlet port and the hydraulic tank flow path in a closed state by pressing the poppet; a valve seat installed to face the poppet so as to form a set pressure in a pressure chamber in the sleeve; a pilot poppet draining the hydraulic fluid in the pressure chamber to the hydraulic tank by opening a flow path of the valve seat when high pressure that exceeds the set pressure is produced in the pressure chamber; a pilot poppet spring elastically supporting the flow path of the valve seat in a closed state by pressing the pilot poppet; a main piston coupled to the sleeve to make a guide coupled to a plug that is coupled to the sleeve and to variably adjust the set pressure in the pressure chamber in accordance with pilot signal pressure that is supplied from an outside; a stopper having a flow path for preventing damping in a contact portion that faces an inner flow path of the main piston and eliminating a stick phenomenon so that the hydraulic fluid in the main piston is smoothly drained; an adjustment plug coupled to the guide to adjust a set pressure of a main piston spring that supports the main piston; a connection port rotatably coupled to an outer side surface of the plug to form a path that communicates with the pilot port; and wherein the flow path for preventing the damping and eliminating the stick phenomenon has a cross-section that is in the form of a “V”-shaped groove, and concave grooves are formed at every angle of 90° or 180° in a circumferential direction and in a length direction of the “V”-shaped groove of the cross-section.