Electric motor actuated stop and self-closing check valve

Abstract

An electric motor actuated stop/check valve for industrial use such as liquid pumping systems which has a controlled opening and closing rate when liquid flow is in a forward direction but closes quickly upon reverse flow of liquid with no action from the electric motor actuator. A valve disc having an elongated disc stem contacts a valve seat when in a closed position to stop liquid flow. Actuation of the valve is by an electric motor which provides movement to an actuator rod which contacts the disc stem. The disc stem and the actuator rod are not connected which allows the valve disc and disc stem free movement, by action of the momentarily back-flowing liquid, to a back-flow preventing closed position when liquid forward flow is reversed. No action by the electric motor is required. A spring biasing the valve disc toward the closed position and a hydraulically operated valve closing-speed regulator reduces or eliminates slamming of the valve disc against the valve seat. In a preferred method of operation liquid surge pressure transients are reduced or eliminated and slamming of valve components is prevented.

1 - 19 . (canceled)  
   
   
       20 . An electric motor actuated stop and self-closing check valve for controlling a forward-flow and a back-flow of a liquid in a liquid conveying line, comprising: 
 A. a valve body having an inlet port and an outlet port relative to said forward-flow of said liquid;    B. a valve seat disposed within said valve body intermediate said ports;    C. a valve disc disposed within said valve body having an elongated disc stem which extends through said valve body, said valve disc and said disc stem being free to move along a longitudinal axis of said valve stem to either: 
 (i) a closed position whereat said valve disc sealingly engages said valve seat to prevent said back-flow of said liquid, or  
 (ii) an open position whereat said valve disc is spaced from said valve seat;  
   D. an electric motor operationally attached to said valve body; and    E. an actuator rod moveable by action of said electric motor to be disposed at either: 
 (i) an extended position whereat said actuator rod contacts said valve stem and restrains said valve disc at said closed position preventing said forward-flow and said back-flow of said liquid, or  
 (ii) a retracted position whereat said actuator rod is retracted and said valve disc is free to move along said longitudinal axis without action by said electric motor, such that: 
 (a) the valve disc moves to said open position solely through action of said forward-flow of said liquid on said valve disc and said forward-flow of said liquid occurs through a portion of said valve body, and  
 (b) the valve disc moves to said closed position through action of a momentary back-flow of said liquid on said valve disc and said back-flow of said liquid is prevented.  
 
   
   
   
       21 . The electric motor actuated stop and self-closing check valve according to  claim 20  further comprising a spring, said spring provides a selected bias to said valve disc and disc stem toward said closed position.  
   
   
       22 . The electric motor actuated stop and self-closing check valve according to  claim 21 , wherein said spring is a compression spring.  
   
   
       23 . A method of controlling a forward-flow and a back-flow of a liquid, which comprises: 
 A. providing a valve body having an inlet port and an outlet port, relative to said forward-flow of said liquid, said valve body comprising: 
 (i) a valve seat disposed within said valve body intermediate said ports,  
 (ii) a valve disc disposed within said valve body having an elongated disc stem which extends through said valve body, said valve disc and disc stem being free to move along a longitudinal axis of said valve stem to either: 
 (a) a closed position whereat said valve disc sealingly engages said valve seat to prevent said back-flow of said liquid, or  
 (b) an open position whereat said valve disc is spaced from said valve seat,  
 
 (iii) an electric motor operationally attached to said valve body, and  
 (iv) an actuator rod moveable by action of said electric motor to be disposed at either: 
 (a) an extended position whereat said actuator rod contacts said valve stem and restrains said valve disc at said closed position preventing said forward-flow and said back-flow of said liquid, or  
 (b) a retracted position whereat said actuator rod is retracted and said valve disc is free to move along said longitudinal axis without action by said electric motor;  
 
   B. extending said actuator rod to said extended position through action of said electric motor to contact said valve stem, and thereby moving said valve disc to said closed position and restraining said valve disc in said closed position;    C. providing said forward-flow of said liquid when said forward-flow of said liquid is desired by: 
 (i) pumping said liquid through action of an electric pump in said forward-flow direction;  
 (ii) retracting said actuator rod to a retracted position through action of said electric motor; and  
 (iii) moving said valve disc to said open position through action of said forward flow of said liquid;  
   D. stopping said forward-flow of said liquid; and    E. preventing said back-flow of said liquid by moving said valve disc to said closed position through either: 
 (i) action of a momentary back-flow of said liquid within said valve body, whereby said momentary back-flow moves said valve disc to said closed position, or  
 (ii) moving said actuator rod to said extended position, thereby moving said valve disc to said closed position.  
   
   
   
       24 . The method according to  claim 23  further comprising biasing said movement of said valve disc during said moving of said valve disc to said closed position by action of said momentary back-flow step.  
   
   
       25 . The method according to  claim 24 , wherein said dampening step further comprises biasing said movement of said valve disc step by action of a spring.  
   
   
       26 . The method according to  claim 25 , wherein said spring a compression spring.  
   
   
       27 . The method according to  claim 23 , wherein said valve body further comprises a hydraulically operated valve disc closing-speed regulator operatively attached to said valve body to control said closing speed of said valve disc, wherein said closing-speed regulator comprises: 
 A. a cylinder operatively attached to said valve body;    B. a piston operatively attached to said disc stem for movement within said cylinder along its longitudinal axis; and    C. a hydraulic oil reservoir with connecting piping to said cylinder, said connecting piping having a check/needle valve.    
   
   
       28 . A liquid conveying line for controlling a forward-flow and a back-flow of a liquid comprising: 
 A. an inlet pipe having for transporting said liquid;    B. an outlet pipe having for transporting said liquid;    C. an electrical pump for creating said forward-flow of said liquid; and    D. a valve body, wherein said valve body comprises: 
 (i) an inlet port relative to said forward-flow of said liquid, said inlet pipe being coupled with said inlet port;  
 (ii) an outlet port relative to said forward-flow of a liquid, said outlet pipe coupled with said outlet port;  
 (iii) a valve seat disposed within said valve body intermediate said ports;  
 (iv) a valve disc disposed within said valve body having an elongated disc stem which extends through said valve body, said valve disc and said disc stem being free to move along a longitudinal axis of said valve stem to either: 
 (a) a closed position whereat said valve disc sealingly engages said valve seat to prevent said back-flow of said liquid, or  
 (b) an open position whereat said valve disc is spaced from said valve seat;  
 
 (v) an electric motor operationally attached to said valve body; and  
 (vi) an actuator rod moveable by action of said electric motor to be disposed at either: 
 (a) an extended position whereat said actuator rod contacts said valve stem and restrains said valve disc at said closed position preventing said forward-flow and back-flow of said liquid, or  
 (b) a retracted position whereat said actuator rod is retracted and said valve disc is free to move along said longitudinal axis of said valve stem without action by said electric motor, such that the valve disc moves to said open position solely through action of said forward-flow of said liquid on said valve disc and said forward-flow of said liquid occurs through said inlet pipe, through said inlet port, through said valve body, through said outlet port, and through said outlet pipe;  
 
   wherein, in the event of a failure of said electric pump or said electric motor, said back-flow of said liquid is prevented by action of a momentary back-flow of said liquid within said valve body acting on said valve disc, thereby moving said valve disc to said closed position.    
   
   
       29 . The liquid conveying line of  claim 28 , wherein said valve further comprises a spring for providing a selected bias to said valve disc and said disc stem toward said closed position.  
   
   
       30 . The liquid conveying line of  claim 29 , wherein said spring is a compression spring.  
   
   
       31 . The liquid conveying line of  claim 28 , wherein the liquid is water.  
   
   
       32 . The liquid conveying line of  claim 28 , wherein said valve body further comprises a hydraulically operated valve disc closing-speed regulator operatively attached to said valve body to control said closing speed of said valve disc, wherein said closing-speed regulator comprises: 
 A. a cylinder operatively attached to said valve body;    B. a piston operatively attached to said disc stem for movement within said cylinder along its longitudinal axis; and    C. a hydraulic oil reservoir with connecting piping to said cylinder, said connecting piping having a check/needle valve.    
   
   
       33 . A method of operating a liquid pumping system comprising: 
 A. providing a liquid;    B. pumping said liquid in a forward-flow direction through action of a pump through an inlet pipe into an inlet port of a valve body, said valve body comprising: 
 (i) said inlet port relative to the forward-flow of said liquid, said inlet pipe being coupled to said inlet port;  
 (ii) an outlet port relative to said forward-flow of said liquid;  
 (iii) a valve seat disposed within said valve body intermediate said ports;  
 (iv) a valve disc disposed within said valve body having an elongated disc stem which extends through said valve body, said valve disc and said disc stem being free to move along a longitudinal axis of said valve stem to either: 
 (a) a closed position whereat said valve disc sealingly engages said valve seat to prevent a back-flow of said liquid, or  
 (b) an open position whereat said valve disc is spaced from said valve seat,  
 
 (v) an electric motor operationally attached to said valve body; and  
 (vi) an actuator rod moveable by action of said electric motor;  
   C. retracting said actuator rod through action of said electric motor to a retracted position, whereby said valve disc is free to move along said longitudinal axis without action from said electric motor;    D. moving said valve disc to said open position through action of said forward-flow of said liquid;    E. transporting said liquid through a portion of said valve body, through said outlet port, and through a portion of said outlet pipe;    F. stopping said pumping step, and thereby stopping said transporting step; and    G. preventing said back-flow of said liquid through said valve body by either: 
 (i) extending said actuator rod through action of said electric motor to an extended position whereby said actuator rod contacts said valve stem and restrains said valve disc at said closed position, thereby preventing said forward-flow and back-flow of said liquid, or  
 (ii) moving said valve disc through action of a momentary back-flow of said liquid to said closed position, thereby preventing said back-flow of said liquid.  
   
   
   
       34 . The method according to  claim 33  further comprising biasing said movement of said valve disc through action of a momentary back-flow of said liquid to said closed position.  
   
   
       35 . The method according to  claim 34 , wherein said biasing step further comprises biasing said movement of said valve disc through action of a momentary back-flow of said liquid to said closed position by action of a spring.  
   
   
       36 . The method according to  claim 35 , wherein said spring is a compression spring.  
   
   
       37 . The method according to  claim 33 , wherein said valve body further comprises a hydraulically operated valve disc closing-speed regulator operatively attached to said valve body to control said closing speed of said valve disc, wherein said closing-speed regulator comprises: 
 A. a cylinder operatively attached to said valve body;    B. a piston operatively attached to said disc stem for movement within said cylinder along its longitudinal axis; and    C. a hydraulic oil reservoir with connecting piping to said cylinder, said connecting piping having a check/needle valve.    
   
   
       38 . The method according to  claim 32 , wherein the liquid is water.  
   
   
       39 . The method according to  claim 32 , wherein the liquid is sewage.