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:
Sep. 25, 1984
Filed:
Feb. 09, 1982
Applicant:
Inventor:
Helmut Motzer, Leinfeld-Echterdingen, DE;
Assignee:
Herion-Werke KG, Fellbach, DE;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F16K / ;
U.S. Cl.
CPC ...
13759616 ; 13759618 ; 91448 ;
Abstract
A hydraulic safety valve for a press has two coaxially movable asymmetric pistons which, in the event of valve malfunction, block communication between the pump port and the working-fluid port while establishing communication between the working-fluid port and the reservoir port. In this position, the two pistons are hydraulically blocked against further movement and this blockage can be removed, and the valve returned to operative condition, only by removing fluid pressure at the pump port.