CUSHION LOAD CONTROL DEVICE AND PRESS MACHINE HAVING CUSHION LOAD CONTROL DEVICE

• Main Author: ONISHI DAI
• Format: Patent
• Language: English
• Published: 29.01.2009
• Subjects: BLASTING; ENGINEERING ELEMENTS AND UNITS; FORGE FURNACES; FORGING; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVEFUNCTIONING OF MACHINES OR INSTALLATIONS; HAMMERING; HEATING; LIGHTING; MEANS FOR DAMPING VIBRATION; MECHANICAL ENGINEERING; MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVINGMATERIAL; PERFORMING OPERATIONS; PRESSING METAL; PUNCHING METAL; RIVETING; SHOCK-ABSORBERS; SPRINGS; THERMAL INSULATION IN GENERAL; TRANSPORTING; WEAPONS; WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS ORPROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL

A cushion load control device for a press machine includes a hydraulic cylinder 2 forming a die cushion, a hydraulic control valve 4 connected to the hydraulic cylinder 2, a hydraulic source 6 connected to the hydraulic cylinder 2 via the hydraulic control valve 4, an opening degree controlling part 11 for outputting a control signal for controlling an opening degree of the hydraulic control valve 4 on the basis of the set pressure value of the hydraulic cylinder, a speed detection unit 15 for detecting the lowering speed of the die cushion, and a signal correction part 18 for correcting the value of the control signal in accordance with the set pressure value and the lowering speed value detected by the speed detection unit 15.