The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 02, 1991
Filed:
Dec. 15, 1989
Applicant:
Inventor:
Chiharu Umetsu, Yokohama, JP;
Assignee:
NHK Spring Co., Ltd., Yokohama, JP;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
B21D / ; F16F / ;
U.S. Cl.
CPC ...
7245313 ; 267119 ; 267122 ;
Abstract
A die cushion device includes a cylinder having a closed one end and the other end with a through-hole. A push rod is inserted into the cylinder through the through-hole and is freely movable in the axial direction of the cylinder. The interior of the cylinder is partitioned by a bellows into a liquid chamber communicating with the through-hole and housing a part of the push rod, and a gas chamber located on the closed end side of the cylinder. Operation liquid is filled in the liquid chamber. Gas is sealed in the gas chamber and pressurizes, through the bellows and the liquid, the push rod in a direction of projecting from the cylinder.