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:
Jan. 10, 1978
Filed:
Jun. 09, 1975
Erich Ruchser, Stetten, DT;
Herion-Werke KG, Fellbach, DT;
Abstract
A sliding-spool direction control valve wherein the valve body has a central space for a center land which is rigid with the shank of the valve spool. The outer lands of the spool have axially extending recesses for the respective end portions of the shank. The center space is disposed between two seats and communicates with a pressure port flanked by two working ports which, in turn, are flanked by two return ports. The outer lands are disposed between the respective working and return ports and are connected with pistons which are movable in the valve body to thereby shift the spool so that the center land engages the one or the other seat. The movements of spool can be initiated by a single electromagnetic pilot valve or by two discrete pilot valves.