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:
Nov. 03, 1992
Filed:
Apr. 10, 1991
Applicant:
Inventors:
Michael Dettmers, Kamen, DE;
Bernd Peters, Dulmen, DE;
Assignee:
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
F15B / ; F15B / ;
U.S. Cl.
CPC ...
91432 ; 91449 ; 91469 ; 137901 ;
Abstract
A valve block in a mine hydraulic system contains a non-return valve which is opened when a hydraulic control signal occurs to connect a pressure fluid feed or return line to a working chamber of an appliance such as a prop. A auxiliary valve is mounted in the block and is operated manually to relieve the working chamber even if the non-return valve remains closed.