Patent ID: 9581256
Date: 2017-02-28
CPC Classifications: F16K,Y10T

Claim:
1. A check valve comprising: a housing; a first flapper rotatable about an axis between open and closed positions; a first post and a second post included on the housing, wherein the axis about which the first flapper is rotatable extends between the first post and the second post; an over-center stop on at least one of the first post and second post; a first spring mechanism operatively positioned between a static component and the first flapper, wherein when the first flapper is in the closed position there is a distance between the first spring mechanism and either the static component or the first flapper; a second flapper rotatable about the axis between the open and closed positions; and a second spring mechanism operatively positioned between the static component and the second flapper, wherein when the second flapper is in the closed position there is a distance between the second spring mechanism and either the static component or the second flapper, wherein the first spring mechanism and the second spring mechanism are springs parallel to one another.