ROTARY HYDRAULIC CYLINDER OF CLAMPING DEVICE DRIVE OF METAL-CUTTING MACHINE Russian patent published in 1994 - IPC

FIELD: machine tool manufacture. SUBSTANCE: hydraulic cylinder has body 1 in which piston 2 is mounted to part it into two cavities. The cavities are connected to oil feed manifolds 12 and 13 through diametrically positioned pilot controlled check valves built in leakage compensating devices. Each device has piston 14 of smaller diameter and piston 15 of larger diameter connected by common rod 16. Piston 14 is mounted in section 17, and piston 15 - in section 18 of a step bore. A through central three-stage hole is made in these pistons and the rod connecting them. Seat 23 to receive check valve 25 of the pilot controlled check valve is made in stage 23, control piston 26 of the pilot controlled check valve is mounted in stage 28 and enters chamber 21 of cup 22. The check valve has pusher 29 with shank 32 between which and the end of stage 18 spring 33 of the check valve is mounted. Stage 28 is connected to oil feed manifolds 12, 13, stage 17 - to corresponding cavities 7 and 8 of the hydraulic cylinder, and chambers 21 - to check valve pilot lines 36 and 37. EFFECT: improved structure. 3 dwg