METHOD TO CONTROL IMPACT ENERGY OF HYDRAULIC IMPACT MACHINE AND ADJUSTABLE HYDRAULIC IMPACT MACHINE Russian patent published in 2005 - IPC

FIELD: metal pipe driving.

SUBSTANCE: according to proposed method including change of value of backward stroke of striker interacting with operating resilient member and working liquid and stepless change of working liquid pressure at which striker changes from backward to forward stroke by changing force of preliminary compression of setting resilient member interacting with valve, it is proposed to control additional speed of valve forward stroke so that time of valve closing be not less than time of forward stroke of striker. Adjustable hydraulic impact machine contains striker unit and impact energy control device. Striker unit includes housing accommodating first working chamber, striker and operating resilient member. Impact energy control device is made in form of housing with second working chamber and valve interacting with setting resilient member. First and second working chambers are hydraulically coupled. Impact energy control device should be preferably equipped with valve forward stroke speed regulator including hydraulically independent shock-absorbing chamber with shock-absorbing liquid divided into upper and lower parts by ring-shock-absorbing piston arranged on valve. Upper and lower parts of shock-absorbing chamber are interconnected through channels, shutoff valve and restrictor.

EFFECT: enlarged sphere of application and improved reliability in operation.

3 cl, 1 tbl, 1 dwg