PURPOSE: To minimize the deviation from the target value of a working speed or tension test speed by making the mass of the movable body of a hydraulic cylinder variable with a freely attachable and detachable additive mass according to working or testing conditions.
CONSTITUTION: A support cylinder is driven by the command from a process control part 1A according to working or test conditions by which an additive mass 15 is lifted and fitted to a ram 7a and is fixed by means of a pin. When a material 16 to be worked attains an optimum temp., an operation command is applied from a process control part 1A to a hydraulic servocontrol device 3 and a hydraulic servocontrol valve 6 supplies the flow rate of the oil pressure proportional to the input signal to a cylinder chamber 7c. The plunger die 10 at the top end of the ram 7a presses the material 16. Since the displacement of the ram 7a is fed back to the device 3 by a displacement detector 14, the deviation from the target value of the working speed is considerably minimized and optimum working is accomplished.
OOKITA TOMOYOSHI
TAKAHASHI MASARU
HARANO SHIYOUTAROU
TASAKA NOBUYOSHI
| JPS4826312A | 1973-04-06 |