Die cushion apparatus of press machine and die cushion controlling method

Patent metadata

Field	Value
Publication number	US-9808848-B2
Application number	US-201414162377-A
Country	US
Kind code	B2
Filing date	Jan 23, 2014
Priority date	Jan 24, 2013
Publication date	Nov 7, 2017
Grant date	Nov 7, 2017

Abstract

According to the die cushion apparatus of a press machine and the die cushion controlling method of the present invention, in holding the cushion pad on standby at a desired standby position, it is possible to hold the cushion pad on standby in parallel with the lower faces of the dies mounted to the slide, and if the lower faces of the dies are inclined, it is possible to hold the cushion pad on standby in the state of being inclined. Through this configuration, it is possible to easily allow the material to come into contact with the lower faces of the dies from the beginning of the die cushion force control (beginning of the collision), and also possible to smoothen the die cushion action in the plane, thereby enhancing the formability.

First claim

What is claimed is:

1. has been replaced with the following:
A die cushion apparatus of a press machine comprising:
a cushion pad supporting a plane face of the cushion pad comprised of cushion pins supporting blank holding plates for holding a material to be formed within a space proximal to a respective set of die including a lower die, in parallel to the lower faces of an upper die affixed to a plane face of the slide;
multiple cushion pad raising and lowering devices configured to raise and lower the cushion pad by separately-controllable multiple driving shafts;
a die cushion position instruction generating unit configured to output multiple position instruction values, each of which individually instructs a position in a raising and lowering direction of the cushion pad corresponding to a position of each driving shaft of the multiple cushion pad raising and lowering devices, the die cushion position instruction generating unit including multiple standby position instruction values for at least holding the cushion pad at a standby position, the multiple standby position instruction values being separate from each other, and outputting the multiple standby position instruction values after knocking out a product;
multiple die cushion position detecting devices configured to detect the position in the raising and lowering direction of the cushion pad corresponding to the position for each driving shaft of the multiple cushion pad raising and lowering devices, and separately output position detection values indicating the detected positions;
an information acquiring device configured to acquire information regarding inclination of the cushion pad in a duration of die cushion force control based on the position detection values outputted from the multiple die cushion position detecting devices; and
a controlling device configured to separately control the multiple cushion pad raising and lowering devices based on the multiple position instruction values outputted from the die cushion position instruction generating unit, and on the multiple position detection values outputted from the multiple die cushion position detecting devices, the controlling device configured to move the cushion pad to the standby position based on the multiple standby position instruction values outputted from the die cushion position instruction generating unit after knocking out the product,
wherein the multiple standby position instruction values are individually adjusted based on the information acquired from the information acquiring device to allow the cushion pad to be held, before applying die cushion force control, on standby holding the material in parallel with lower faces of dies mounted to the slide of the press machine in an inclined state of the dies with respect to the plane face of the slide of the press machine.

2. A die cushion controlling method in the die cushion apparatus of a press machine according to claim 1 , the die cushion controlling method comprising:
a step of outputting the multiple standby position instruction values that are set from the die cushion position instructing unit before a test press so as to hold the cushion pad at the standby position;
a step of driving the slide of the press machine so as to carry out the test press;
a step of acquiring information regarding the inclination of the cushion pad in the duration of the die cushion force control during the test press; and
a step of adjusting, based on the acquired information, the multiple standby position instruction values set in the die cushion position instructing unit so as to hold the inclination of the cushion pad at the standby position of the cushion pad.

3. The die cushion apparatus of a press machine according to claim 1 , further comprising a correcting device configured to, based on the information acquired from the information acquiring device, automatically correct the multiple standby instruction values set in the die cushion position instructing unit so as to hold inclination of the cushion pad at the standby position of the cushion pad.

4. The die cushion apparatus of a press machine according to claim 1 , wherein the information acquiring device acquires the multiple position detected values outputted from the multiple die cushion position detecting devices as the information regarding the inclination of the cushion pad, wherein the multiple position detected values are associated with each time in the duration of the die cushion force control, a position of the slide, or die cushion force applied onto the multiple driving shafts.

5. The die cushion apparatus of a press machine according to claim 1 , wherein the multiple cushion pad raising and lowering devices function as cushion force generating devices that generate the die cushion force via the multiple driving shafts at a time of lowering the slide of the press machine.

Assignees

• Aida Eng Ltd

Inventors

• Kohno Yasuyuki
• Kondo Tadahiro
• Iwamura Ryosho

Classifications

• B21D24/02 Primary

  Die-cushions · CPC title

• B30B15/24

  controlling the movement of a plurality of actuating members to maintain parallel movement of the platen or press beam · CPC title

• B21D24/14 Primary

  pneumatically or hydraulically · CPC title

• B21D22/22

  with devices for holding the edge of the blanks (B21D22/24 - B21D22/30 take precedence; shaping over a die without external former B21D11/02) · CPC title

• B21D24/08

  Pneumatically or hydraulically loaded blank holders · CPC title