Patent ID: 7337807
Filing Date: 2008-03-04
Classification: E02F,F15B,Y10T

Abstract:
1. A hydraulic control valve with a regeneration function, comprising: a main body formed of a supply fluid passage to which pressurized fluid from outside is supplied, at least one port for supplying the pressurized fluid in the supply fluid passage to an actuator or receiving the return fluid from the actuator, a tank fluid passage for discharging the return fluid from the actuator to an outside storage tank, and a first regeneration fluid passage for supplying part of the return fluid from the actuator to the supply fluid passage; a spool movably installed inside the main body for controlling the flow of pressurized fluid by opening/closing the connections of the supply fluid passage, the port(s), the tank fluid passage, and the first regeneration fluid passage, respectively, and comprising a second generation fluid passage that supplies the pressurized fluid of the first regeneration fluid passage to the supply fluid passage; and a regeneration valve installed between the first regeneration fluid passage and the tank fluid passage for returning only part of the pressurized fluid of the first regeneration fluid passage to the tank fluid passage to maintain pressure of the first regeneration fluid passage at a designated value, and for supplying the pressurized fluid to the second regeneration fluid passage; and if the pressure of the supply fluid passage is higher than a predetermined pressure, changing the pressure of the first regeneration fluid passage in accordance with a change of the pressure of the supply fluid passage, wherein the regeneration valve is comprised of: a sleeve installed between the first regeneration fluid passage and the tank fluid passage, and formed of a first fluid passage communicating with the first regeneration fluid passage and a second fluid passage communicating with the tank fluid passage; a main poppet movably installed inside the sleeve by being elastically supported by a first spring for changing an opening area of the second fluid passage, and comprising a back pressure chamber formed therein; a pilot poppet movably installed inside the sleeve by being elastically supported by a second spring, and if pressure of the back pressure chamber exceeds a predetermined pressure, discharging pressurized fluid of the back pressure chamber to the tank fluid passage; a pilot piston movably installed on a piston passage formed in front of the main poppet to be in contact with the front end portion of the pilot poppet; and a piston slidably installed on the front side of the sleeve for the rear end of the piston to be in contact with the front end portion of the pilot piston, and if the pressure of the supply fluid passage applied to the front end portion of the pilot piston exceeds the predetermined pressure set for the pilot poppet, moving the pilot piston and the pilot poppet backward.