GB1282179A - Device for generating hydraulic fluid pressure pulses - Google Patents

Abstract

1282179 Hydraulic pulse generators Reciprocating pumps Compressors VSESOJUZNY NAUCHNO-ISSLEDOVATELSKY I PROEKTNOKONSTRUKTORSKY INSTITUT DOBYCHI UGLYA GIDRAVUCHESKIM SPOSOBOM 31 Oct 1969 53561/69 Headings F1A F1N and F1P In a hydraulic pulse generator apparatus for producing a succession of hydraulic pulses through an end port 11 of a fluid-filled chamber 4 by means of a differential piston 2 advanced by compressed air stored in a vessel 6 in open communication through a channel 5 with a cylinder space 3 and wherein the return stroke of piston 2 against airpressure at 3, 6 is effected by first clamping the piston head 21 by means 20 to a hydraulically actuated piston 19 and then by supplying hydraulic fluid to a chamber 18a thus retracting connected pistons 2, 9 after which the clamp 20 is automatically released thus allowing a further working stroke of piston 2, air vessel 6 is periodically replenished by using piston 2 as a compressor piston for which purpose the cylinder is provided with a suction valve 16 and with a discharge valve 17 which during air replenishment operation of the apparatus is positioned across channel 5 so as to prevent air-flow from vessel 6 to space 3. The clamp 20 comprises a sleeve 23 rigidly secured to piston 19 and has ports 24 through which slide radially outwardly biassed cams 25 for engagement in a groove 22 behind the head 21. The sleeve 23 also has ports 26 along which slide a cup-shaped member 27 provided with a plunger 29 and grooves 28 which latter when member 29 and hence member 27 is urged forward by abutment against a fixed adjustable plug 30 receives the released cams 25. In operation for producing hydraulic pressure pulses, plug 30 is positioned in the broken line position shown as is the valve 17 whereas during replenishment of compressed air vessel 6 the plug 30 and valve 17 are in their alternative full line positions.