GB1178093A - Regenerative Valve Plunger - Google Patents

Abstract

1,178,093. Valves. GENERAL SIGNAL CORP. 2 July, 1968 [20 Oct., 1967], No. 31464/68. Heading F2V. A double-acting regenerative spool valve has an axially slidable spool 11 formed with a central axial bore in which are housed load drop check valves 39, 44 and a regenerative check valve 51. The check valves 44, 51 which are spring biased to a closed position are biased open by the pressure in space 47 between them and the check valve 51 is also biased closed by the pressure in chamber 54 which is connected by restricted passage 55 to right-hand spool neck 27 and by passage 57 and check valve 58 to the left-hand spool neck 26. In use with a doubleacting cylinder 25, movement to the left of the spool connects the pump 23 to the head of the cylinder 25 via chamber 17, spool transverse passage 37, check valve 39, spool transverse passage 38, and chamber 22 while the returnflow from cylinder 25 is via chamber 21, spool transverse bore 43, check valves 44, 45, spool transverse passage 41, chamber 19, and exhaust manifold branch 14. In this position of the spool, the check valve 58 is open so that the pump pressure in chamber 54 holds the regenerative check valve 51 closed but if the load aids the movement of piston 25a back-pressure in chamber 54 will decrease below pressure in space 47 so that check valve 51 will open to permit return fluid to be added to the supply fluid. Movement to the right of the spool connects the pump to the rod end of chamber 25 via chamber 16, transverse spool passage 43, check valve 44, transverse spool passages 42 and chamber 21 while the return flow is via chamber 22, transverse spool passage 37, check valve 39, transverse spool passage 38, chamber 20 and exhaust manifold branch 14a.