Check valve

• US 4,188,973 A
• Filed: 12/06/1977
• Issued: 02/19/1980
• Est. Priority Date: 12/06/1977
• Status: Expired due to Term

• Current Assignee: Anderson, Greenwood & Co. (Johnson Controls International plc)
• Original Assignee: Anderson, Greenwood & Co. (Johnson Controls International plc)
• Inventors: Dane, Oscar, Weise, Irvin B.
• Primary Examiner(s): Cline, William R.
• Application Number:
  US05/858,080
• Time in Patent Office: 805 Days
• Field of Search: 251/50, 251/51, 251/52, 137/856, 137/527.4, 137/514, 137/514.7, 137/527, 137/527.2, 137/527.6, 137/527.8
• US Class Current: 137/514
• CPC Class Codes: F16K 15/033 spring-loaded
• CPC Class Codes: Y10T 137/785 With retarder or dashpot
• CPC Class Codes: Y10T 137/7853 Enlarged piston on end of valve stem
• CPC Class Codes: Y10T 137/7901 Valve head movably connected for accommodation to seat

Abstract

A check valve having a body with an inlet, an outlet, a valve seat surrounding communication between said inlet and said outlet, a valve chamber in said body communicating with said outlet, a bonnet having a cylinder therein with the open end communicating with said valve chamber where the bonnet is secured to said body, a valve disc resiliently secured to an arm which is pinned to allow the valve disc to be pivoted from a position engaging said valve seat to a position in said valve chamber, a piston in the bonnet cylinder and having a connecting rod secured to said valve disc arm so that said piston reciprocates in said cylinder as said valve disc moves, a port through the piston to allow passage of the fluid flowing through the check valve to flow to opposite sides of the piston as it reciprocates in the cylinder, a reed valve secured to said piston and adapted to substantially close said port during closing movement of said valve disc but allow relatively free flow of fluids through said port during opening movement of the valve disc, a seal ring having sufficient resiliency and being contoured to provide a seal between said piston and said cylinder during reciprocation and tilting of said piston within said cylinder, all moving parts being contained within said valve body and said bonnet, said piston and said valve disc having substantially the same diameter to cancel out effects of back surge.

Claims

1. A check valve comprising

a body having an inlet, an outlet, a seat surrounding communication through said body between said inlet and said outlet, and a valve chamber communicating with said outlet downstream of said valve seat and open to the exterior of said body,

a valve disc,

means for pivotally mounting said valve disc within said chamber for movement into and from engagement with said valve seat to control flow therethrough,

a bonnet having a cylinder defined therein,

means for securing said bonnet to said body with said cylinder in communication with said valve chamber,

a piston positioned within said cylinder for reciprocation therein,

means connecting said piston to said valve disc, the valve disc, its mounting means, the piston and the means connecting the piston to the valve disc being totally enclosed within said body chamber and said bonnet cylinder, and

means associated with said piston for allowing relatively free movement of said piston responsive to the opening movement of said valve and to restrain the movement of said piston responsive to closing movement of said valve by controlling the flow of fluids from opposite sides of said piston which fluids are the fluids flowing through said valve, said piston is positioned within said cylinder so that fluid pressure downstream of said valve seat is exerted on said piston to urge it in the direction of its movement during opening of said valve disc, the diameter of said piston is substantially the same as the diameter of said valve disc, whereby the movements due to back surge are substantially cancelled.

2. A check valve according to claim 1 wherein said movement controlling means for said piston includes

a port extending through said piston, and

a reed valve secured to the valve chamber side of said piston.

3. A check valve according to claim 1, wherein said means connecting said piston to said valve disc includes

a connecting rod,

means for pivotally connecting said connecting rod to said valve disc, and

means for securing said connecting rod to said piston, and including

a seal ring mounted in surrounding relationship to said piston,

said seal ring having an outer spherical surface with a radius equal to the radius of said cylinder whereby a seal is maintained between said piston and said cylinder during reciprocation and tilting of said piston in said cylinder.