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:
Dec. 04, 1979
Filed:
Jan. 20, 1978
Gunther Schwerin, Moglingen, DE;
Robert Bosch GmbH, Stuttgart, DE;
Abstract
A check valve with pilot actuation for hydraulic systems has a valve housing with a main bore and main seat, a main valve member movable in the main bore between a closed position and an open position and having an additional inner bore with a conical mouth at one end thereof, a pilot valve member movable between a closed position and an open position in said additional bore, and a push rod operative for moving the pilot valve member to the open position thereof. The push rod has a first thinner portion and the second thicker portion forming a shoulder. A conical transitional portion is formed between the above two portions and is complementary to the conical mouth of the bore of the main valve member. The push rod has pressure-relief clearances formed in the region of the transitional portion and the shoulder, and so located that when the transitional conical portion is seated on the conical mouth fluid in said additional bore can pass through the clearances.