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. 12, 1978
Filed:
Jun. 22, 1977
Rudiger Hoffmann, Sindelfingen, DE;
Abstract
A check valve, especially for vacuum-operated installations in motor vehicles, which includes a two-partite housing and a roller diaphragm secured between the housing parts provided with inlet and outlet channels; the roller diaphragm which is pressed against its sealing seat by a prestressed spring, cooperates by means of its ring-shaped, curved diaphragm portion as movable sealing part with the bottom of one housing part constructed as sealing seat in such a manner that a central bore provided in the section of the roller diaphragm located on the side of the spring, connects the inlet channel terminating outside of the curved diaphragm portion with the outlet channel of the housing part, when the curved diaphragm portion lifts off from the sealing seat upon exceeding a predetermined differential pressure.