| 摘要 |
PURPOSE:To provide a hydraulic cylinder device which is reduced in size and permits actuation of a working cylinder rod at a higher speed by forming the working cylinder and boosting cylinder into one body, forming the boosting cylinder into a recessed shape and providing a hydraulic control means. CONSTITUTION:Oil is admitted into an oil pressure chamber 6 on the 1st piston head side via a hydraulic directional control valve 12 and the oil in an oil pressure chamber 5 on a rod side is discharged in a hydraulic cylinder device for a press machine, etc. When the pressure in a piping 16a increases on advancing of the 1st piston rod 4, a sequence valve 14 opens and the oil is admitted via a hydraulic directional control valve 13 into the 2nd cylinder 10, then the 2nd piston rod 8 plunges into the 1st chamber 6. The oil pressure in the chamber 6 rises in this stage and the 1st piston rod 4 advances at a low speed under the high thrust. When the load decreases, a sequence valve 14 is closed and the rod 4 advances at a high speed under the low thrust. |
