# US 8,042,375 B2 · Press die cushion controller

> Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt

- Number: US 8,042,375 B2
- Document ID: US8042375B2
- Status: Granted
- Kind: B2
- Application number: 12/225,461
- Filed: 2007-03-02
- Published: 2009-05-21
- Granted: 2011-10-25
- Earliest claimed: 2006-03-22
- Assignees: Komatsu Industries Corporation
- Inventors: Yuichi Suzuki
- Web page: https://patentgrep.com/patent/US8042375B2

## CPC

- G05B 19/19: characterised by positioning or contouring control systems, e.g. to control position from one programmed point to another or to control movement along a programmed continuous path
- B21D 24/10: Devices controlling or operating blank holders independently, or in conjunction with dies
- G05B 2219/42094: Speed then pressure or force loop
- G05B: CONTROL OR REGULATING SYSTEMS IN GENERAL; FUNCTIONAL ELEMENTS OF SUCH SYSTEMS; MONITORING OR TESTING ARRANGEMENTS FOR SUCH SYSTEMS OR ELEMENTS (systems for controlling or regulating non-electric variables G05D; systems for regulating electric or magnetic variables G05F; control devices or systems insofar as characterised by mechanical features only G05G)
- B21D: WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL (working or processing of wire B21F)

## Abstract

A die-cushion controlling device includes: a position-command-signal outputting section for outputting a position command signal of a die-cushion pad; a position detecting means for detecting a position of the die-cushion pad; a position comparing section for outputting a position deviation signal corresponding to a deviation between the target position value based on the position command signal and a position detection value based on a position detection signal; a position controlling section for outputting a position-speed command signal based on the position deviation signal; a speed controlling section for outputting a motor-current command signal based on the position-speed command signal from the position controlling section; a servo amplifier for generating a current corresponding to the motor-current command signal; and an output switching section that, based on a press signal output when a slide has reached a bottom dead center, switches the position detection signal from the position detection means to the position command signal from the position command signal outputting section.

## Claims

### Claim 1

A die-cushion controlling device for a press machine, comprising:
a position-command-signal outputting section that outputs a position command signal corresponding to a target position value of a die-cushion pad;
a position detector that detects a position of the die-cushion pad;
a position comparing section that outputs a position deviation signal corresponding to a deviation between the target position value based on the position command signal and a position detection value based on a position detection signal from the position detector;
a position controlling section that outputs a position-speed command signal based on the position deviation signal;
a speed controlling section that outputs a motor-current command signal based on the position-speed command signal from the position controlling section;
a servo amplifier that feeds an electric servo motor for driving a die cushion with a current corresponding to the motor-current command signal; and
an output switching section that, based on a press signal that is outputted at a timing when a slide of the press machine reaches a bottom dead center position, switches the position detection signal from the position detector for the position command signal from the position-command-signal outputting section so that the position comparing section receives the position detection signal instead of the position command signal.

### Claim 2 (depends on 1)

The die-cushion controlling device for a press machine according to claim 1, further comprising:
a pressure-command-signal outputting section that outputs a pressure command signal corresponding to a target pressure value;
a pressure detector that detects a pressure applied on the die-cushion pad;
a pressure comparing section that outputs a pressure deviation signal corresponding to a deviation between the target pressure value based on the pressure command signal and a pressure detection value based on a pressure detection signal from the pressure detector;
a pressure controlling section that outputs a pressure-speed command signal based on the pressure deviation signal; and
a position/pressure-control switching section that selects one having a smaller value of the pressure-speed command signal and the position-speed command signal,
wherein the speed control section outputs a motor current command signal based on the pressure-speed command signal when the pressure-speed command signal is outputted from the position/pressure-control switching section.