公开(公告)号：WO1992007711A1

公开(公告)日：1992-05-14

申请号：PCT/JP1991001501

申请日：1991-11-01

Applicant: KABUSHIKI KAISHA KOMATSU SEISAKUSHO ,  YOSHIKAWA, Eiji

Inventor： KABUSHIKI KAISHA KOMATSU SEISAKUSHO

IPC: B30B15/00

CPC classification number: B21D24/02 ,  B21D24/14 ,  B30B15/16

Abstract: An object of the present invention is to provide a die cushion device of a press machine, wherein preliminary acceleration can be applied to a die cushion pad following the descent of a slide at an accurate timing and with high accuracy, and such improvements can be achieved that a difference in pressure between a real pressure in a hydraulic cylinder and a preset target value can be eliminated in the vicinity of a bottom dead center of a slide stroke. Said die cushion device comprises an air pressure cylinder (6) and a hydraulic cylinder (7) having a servo valve (40) for controlling a discharge pressure and fed with pressure oil through suction, wherein the supply of the pressure oil to the hydraulic cylinder (7) at the time of said preliminary acceleration is performed through a pressure oil supply circuit (16) provided with a servo valve (22) being controlled by a main body (14) of a control device, and a control signal from a main body (27) of a pressure control device for controlling the servo valve (40) for controlling the discharge pressure in the hydraulic cylinder (7) is corrected in accordance with a speed of slide descent and a speed of press operation.

公开(公告)号：WO1991004116A1

公开(公告)日：1991-04-04

申请号：PCT/JP1990001213

申请日：1990-09-21

Applicant: KABUSHIKI KAISHA KOMATSU SEISAKUSHO ,  TSURUTA, Katsuji ,  YOSHIKAWA, Eiji

Inventor： KABUSHIKI KAISHA KOMATSU SEISAKUSHO

IPC: B21D43/05

CPC classification number: G05B19/416 ,  B21D43/055 ,  G05B2219/43091 ,  G05B2219/50049 ,  G05B2219/50386

Abstract: A control device for a work feeder automatically carrying in and out a work in association with the movement of the press, which device is capable of automatically setting an optimum motion curve according to the shapes and sizes of the work and metallic mold of the press, and also capable of detecting whether unreasonable operation conditions are set or not. In order to perform the above functions, the device is provided with means for setting respective degrees of angle at the start and end of the motion of the crank shaft as well as means of operation for specifying a motion curve of movable shafts on the basis of the set values. The device is further provided with means to calculate the maximum allowable operation strokes of the press, compares the calculated strokes with the set number of strokes for evaluation thereof, and checks an overload on the motor.