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:
Aug. 04, 2015
Filed:
Mar. 30, 2012
Kosei Yamaguchi, Yokohama, JP;
Kosei Yamaguchi, Yokohama, JP;
PIOLAX INC., Yokohama-Shi, Kanagawa, JP;
Abstract
A check valve includes a casing including a positive pressure valve seat, a positive pressure valve urged by a positive pressure valve spring and including a negative pressure valve seat, and a negative pressure valve assembled to the positive pressure valve and urged by a negative pressure valve spring, where the positive pressure valve includes an inner cylinder, an outer cylinder that is connected with an outer circumference of the inner cylinder via ribs, and passages formed between the inner cylinder and the outer cylinder, where the positive pressure valve spring is disposed the casing and the outer cylinder, and where the negative pressure valve spring is disposed in the inner cylinder.