Thermostatic mixing valve

Abstract

A thermostatic mixing valve for the mixing of a first fluid and second fluid is disclosed. The thermostatic mixing valve is configured to produce a mixed fluid of a particular temperature from a first fluid of a temperature higher than or equal to the particular temperature of a second fluid of a temperature lower than or equal to the particular temperature. The thermostatic mixing valve includes a valve body having a first fluid inlet, a second fluid inlet, and a mixed fluid outlet. The thermostatic mixing valve also includes a valve member configured to control the rate of flow of at least the first fluid. The valve member includes a thermostatic control device in communication with the mixed fluid and a shuttle coupled to the thermostatic control device, configured for movement within a liner, and oriented to adjustably engage the flow of at least the first fluid through at least one opening within a wall of the liner, the direction of flow of the first fluid being at least partially transverse with respect to the shuttle. At least one fluid inlet may include a check valve configured to prevent fluid from flowing out of the valve through the inlet. The check valve includes a first check valve member which is stationary, a second check valve member which is movable and engageable with the first check valve member, and a spring for urging the second check valve member into engagement with the first check valve member and for defining the path of motion of the second check valve member.

1 . A mixing valve comprising: a valve body formed to include a hot fluid inlet, a cold fluid inlet, and recirculated fluid inlet, and a mixing chamber positioned to receive fluid from the hot and cold fluid inlets, a thermostat to sense the temperature of fluid in the mixing chamber and move a valve member in response to changes in the temperature of fluid in the mixing chamber, the recirculated fluid inlet positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet.  
   
   
       2 . The mixing valve of  claim 1 , wherein the recirculated fluid inlet is positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction of cold fluid flows through the cold fluid inlet.  
   
   
       3 . The mixing valve of  claim 1 , further comprising a check valve, wherein the recirculated fluid inlet is positioned downstream of the check valve so that, when the check valve is in a closed orientation, the flow of fluid through the cold fluid inlet is substantially obstructed, and the recirculated fluid inlet is substantially unobstructed.  
   
   
       4 . The mixing valve of  claim 1 , therein the recirculated fluid inlet is positioned so that fluid flows from the recirculated fluid inlet in a direction that is substantially transverse to the direction of movement of the valve member.  
   
   
       5 . The mixing valve of  claim 4 , wherein the recirculated fluid inlet is positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction in which cold fluid flows through the cold fluid inlet.  
   
   
       6 . The mixing valve of  claim 1 , wherein the check valve includes a check valve member movable between a position engaging a seat to restrict flow of fluid past the seat to a position permitting flow of fluid past the seat, and the recirculated fluid inlet is positioned so that the fluid flows from the recirculated fluid inlet in a direction that is substantially transverse to the direction of movement of the check valve member.  
   
   
       7 . The mixing valve of  claim 6 , wherein the recirculated fluid inlet is positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction in which cold fluid flows through the cold fluid inlet.  
   
   
       8 . The mixing valve of  claim 1 , further comprising a cap, and the recirculated fluid inlet is an opening formed in the valve body and is sized to receive the cap when the recirculated fluid inlet is not in use.  
   
   
       9 . The mixing valve of  claim 8 , wherein the cap and the opening are complementarily threaded.  
   
   
       10 . The mixing valve of  claim 2 , further comprising a threaded cap, and the recirculated fluid inlet is an opening formed in the valve body and is complementarily threaded and sized to receive the cap when the recirculated fluid inlet is not in use.  
   
   
       11 . A method of mixing fluids comprising: providing a valve body formed to include a hot fluid inlet, a cold fluid inlet, and a mixing chamber positioned to receive fluid from the hot and cold fluid inlets, positioning a thermostat at least partially in the mixing chamber to sense the temperature of fluid in the mixing chamber and move a valve member in response to changes in the temperature of fluid in the mixing chamber, and introducing a recirculated fluid into the fluid flowing through the cold fluid inlet to permit blending of cold fluid and recirculated fluid.  
   
   
       12 . The method of  claim 11 , wherein providing a valve body includes providing a valve body formed to include a recirculated fluid inlet positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction of cold fluid flows through the cold fluid inlet.  
   
   
       13 . The method of  claim 11 , wherein providing a valve body includes providing a valve body formed to include a recirculated fluid inlet, the method further comprising a check valve, wherein the recirculated fluid inlet is positioned downstream of the check valve so that, when the check valve is in a closed orientation, the flow of fluid through the cold fluid inlet is substantially obstructed, and the recirculated fluid inlet is substantially unobstructed.  
   
   
       14 . The method of  claim 13 , wherein the recirculated fluid inlet is positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction in which cold fluid flows through the cold fluid inlet.  
   
   
       15 . The method of  claim 13 , wherein the check valve includes a check valve member movable between a position engaging a seat to restrict flow of fluid past the seat to a position permitting flow of fluid past the seat, and the recirculated fluid inlet is positioned so that fluid flows from the recirculated fluid inlet in a direction that is substantially transverse to the direction of movement of the check valve member.  
   
   
       16 . The method of  claim 15 , wherein the recirculated fluid inlet is positioned relative to the cold fluid inlet to permit fluid to flow through the recirculated fluid inlet into the cold fluid inlet in a direction substantially transverse to the direction in which cold fluid flows through the cold fluid inlet.  
   
   
       17 . The method of  claim 12 , further comprising providing a cap, and the recirculated fluid inlet is an opening formed in the valve body and is sized to receive the cap when the recirculated fluid inlet is not in use.  
   
   
       18 . The method of  claim 17 , wherein providing a cap includes providing a cap complementarily threaded with complementary threads formed at the opening.  
   
   
       19 . The method of  claim 12 , further comprising providing a threaded cap, and the recirculated fluid inlet is an opening formed in the valve body and is complementarily threaded and sized to receive the cap when the recirculated fluid inlet is not in use.  
   
   
       20 . A system for mixing fluids comprising: a mixing valve and a fluid conducting network, the mixing valve including a mixed fluid outlet, a hot fluid inlet, a cold fluid inlet, a recirculated fluid inlet, a valve member to adjust the amount of fluid flowing through at least one of the hot and cold fluid inlets, and a thermostat to move the valve member in response to changes in temperature of the fluid adjacent the thermostat, the fluid conducting network coupled to the mixing valve and including a hot fluid supply line to supply hot fluid to the hot fluid inlet of the mixing valve, a cold fluid supply line to supply cold fluid to the mixing valve, a mixed water line coupled to the mixed fluid outlet, and a recirculation line coupled between the mixed water line and the recirculated fluid inlet to permit flow of mixed fluid into the recirculated fluid inlet.