Patent ID: 7121291

Claim:
A check valve comprising; a casing member, a movable valve body installed in said casing member, a latching member which is formed at an inner wall of said casing member and generates forward flux while the movable valve body is latched, and an airtight valve seat which is formed at an inner wall of said casing member and closes said casing member to suppress backward flux while the movable valve body is seated, wherein the movable valve body is made in tear-drop shape, an inclined level of a forward portion of the movable valve body that is configured to engage the latching member being set smaller than an inclined level of a backward portion of the movable valve body that configured to engage the airtight valve seat, the tear-drop shape facilitating absolute latching of the movable valve body at the latching member and stable flow of a circulating substance past the forward portion.