DIE CUSHION DEVICE

• US 20110036140A1
• Filed: 05/07/2009
• Published: 02/17/2011
• Est. Priority Date: 05/22/2008
• Status: Active Grant

• Current Assignee: Komatsu Industries Corporation (Komatsu Ltd.), Komatsu Ltd.
• Original Assignee: Komatsu Industries Corporation (Komatsu Ltd.), Komatsu Ltd.
• Inventors: Ito, Hiroyuki, Morimoto, Shigeo, Miyasaka, Takuji, Sato, Hirohide, Arikabe, Takeo, Watanabe, Shyoji, Nagashima, Shigenori
• Granted Patent: US 8,850,865 B2
• Time in Patent Office: Days
• US Class Current: 72/351
• CPC Class Codes: B21D 24/02 Die-cushions
• CPC Class Codes: B21D 24/10 Devices controlling or operating blank holders independently, or in conjunction with dies

Abstract

A die cushion device includes a cushion pad, a support section, a servomotor, and a shock absorber device. The support section supports the cushion pad. The servomotor raises and lowers the support section for raising and lowering the cushion pad. The shock absorber device includes a damping section and relieves shock between the cushion pad and the support section. The damping section generates reaction force in accordance with the relative speed of the cushion pad with respect to the support section.

Claims

1. A die cushion device comprising:

a cushion pad;

a support section supporting the cushion pad;

a servomotor configured to raise and lower the support section for raising and lowering the cushion pad; and

a shock absorber device configured to relieve a shock between the cushion pad and the support section, the shock absorber device including a damping section configured to generate a reaction force in accordance with a relative speed of the cushion pad with respect to the support section.

2. The die cushion device according to claim 1, wherein

the shock absorber device further includes an elastic section configured to generate a reaction force in accordance with a relative displacement of the cushion pad with respect to the support section.

3. The die cushion device according to claim 1, wherein

the shock absorber device further includes

a liquid pressure chamber filled with a liquid, the liquid pressure chamber being disposed between the cushion pad and the support section, and

a liquid flow path allowing the liquid to pass therethrough, the liquid flow path being connected to the liquid pressure chamber, and

the damping section is a restrictor disposed in the liquid flow path.

4. The die cushion device according to claim 2, wherein

the shock absorber device further includes

a liquid pressure chamber filled with a liquid, the liquid pressure chamber being disposed between the cushion pad and the support section, and

a liquid flow path allowing the liquid to pass therethrough, the liquid flow path being connected to the liquid pressure chamber, and

the elastic section is an accumulator disposed in the liquid flow path.