Title:
METHOD OF PREVENTING PLUNGERS FROM BOTTOMING IN DIE CUSHION PIN PRESSURE EQUALIZING SYSTEM
Document Type and Number:
WIPO Patent Application WO/1992/022391
Kind Code:
A1
Abstract:
In a die cushion pin pressure equalizing system wherein a plurality of die cushion pins are vertically movably provided in the bolster of a press machine, pressure equalizing hydraulic cylinders supported by die cushions are respectively provided downwardly of the plurality of die cushion pins and the plurality of pressure equalizing hydraulic cylinders are connected to one another through hydraulic paths, so that oil pressure is applied to the pressure equalizing hydraulic cylinders and the hydraulic paths, preload oil pressure acting on the plurality of pressure equalizing cylinders is raised to thereby prevent plungers of the plurality of pressure equalizing cylinders from bottoming.
Inventors:
KAJI NOBUYUKI (JP)
Application Number:
PCT/JP1992/000775
Publication Date:
December 23, 1992
Filing Date:
June 17, 1992
Export Citation:
Assignee:
TOYOTA MOTOR CO LTD (JP)
KOMATSU MFG CO LTD (JP)
KOMATSU MFG CO LTD (JP)
International Classes:
B21D24/02; B30B15/02; B30B15/06; (IPC1-7): B21D24/02; B30B15/02
Foreign References:
| JPS6220711U | 1987-02-07 | |||
| JPS623219U | 1987-01-10 |
Other References:
See also references of EP 0592670A4
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