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. 10, 1992
Filed:
Dec. 10, 1991
Masahiko Nakazawa, Tokyo, JP;
Hisayoshi Matsumoto, Saitama, JP;
Masako Kiyohara, Kumamoto, JP;
Abstract
A check valve comprises a valve body having inlet and outlet passages and a cavity in which a diaphragm operates. The inlet passage connects with the cavity through an upstream wall partly defining the cavity and the outlet passage connects with the cavity through a downstream wall partly defining the cavity. The diaphragm has an annular sheet metal part which is secured to one of the walls and carries a movable seal. The movable seal cooperates with a sealing element to provide a circular fluid seal. In a first embodiment, the inlet passage connects with the cavity through openings located inside the periphery of the circular fluid seal. In a second embodiment the inlet passage connects with the cavity through openings located outside the periphery of the circular fluid seal. The movable seal may be a sealing surface in which case the sealing element is a seal ring, or the movable seal may comprise a seal ring in which case the sealing element is a sealing surface.