Pressure-driven metered mixing dispensing pumps and methods

Abstract

A pressure-driven metered mixing dispensing pump has a first chamber, a second chamber, a third chamber in fluid communication with the first and second chambers and a fluid outlet in fluid communication with the third chamber. Selectively supplying a first fluid into the first chamber causes at least a portion of the first fluid and at least a portion of second fluid supplied into the second chamber to be mixed in the third chamber and dispensed through the fluid outlet.

What is claimed is: 
     
         1 . A pressure-driven metered mixing dispensing pump, comprising:
 a first chamber;   a second chamber;   a third chamber in fluid communication with the first and second chambers; and   a fluid outlet in fluid communication with the third chamber, wherein selectively supplying a first fluid into the first chamber causes at least a portion of the first fluid and at least a portion of second fluid supplied into the second chamber to be mixed in the third chamber and dispensed through the fluid outlet.   
     
     
         2 . A pressure-driven metered mixing dispensing pump as defined in  claim 1 , further comprising a piston having a first orifice defined therethrough, and wherein the first and third chambers are in fluid communication via the first orifice. 
     
     
         3 . A pressure-driven metered mixing dispensing pump of  claim 2 , wherein the first orifice is configured to spray the at least a portion of the first fluid into the third chamber. 
     
     
         4 . A pressure-driven metered mixing dispensing pump of  claim 2 , wherein the piston has a second orifice defined therethrough, and the first and third chambers are in fluid communication via the first and second orifices. 
     
     
         5 . A pressure-driven metered mixing dispensing pump of  claim 1 , further comprising at least one of an internal bypass line, an external bypass line, a water piston seal and/or a diaphragm-type seal having a non-zero predetermined bleeding flow rate, wherein the first and third chambers are in fluid communication via the at least one of the internal bypass line, the external bypass line, the water piston seal, and/or the diaphragm-type seal. 
     
     
         6 . A pressure-driven metered mixing dispensing pump of  claim 1 , wherein the selective supplying of the first fluid from a first fluid source into the first chamber causes substantially all of the second fluid in the third chamber to be removed from the third chamber. 
     
     
         7 . The pressure-driven metered mixing dispensing pump of  claim 1 , further comprising a first one-way valve positioned between the second chamber and the third chamber. 
     
     
         8 . The pressure-driven metered mixing dispensing pump of  claim 7 , wherein the first one-way valve is disposed at least partially within the piston. 
     
     
         9 . The pressure-driven metered dispensing pump of  claim 1 , wherein the first fluid is supplied by a domestic water source, and the second fluid comprises a laundry treating chemistry. 
     
     
         10 . A pressure-driven metered mixing dispensing pump, comprising:
 a housing and a piston disposed in the housing;   a first chamber within the housing;   a second chamber within the housing;   a third chamber within the housing and in fluid communication with the first and second chambers; and   a fluid outlet in fluid communication with the third chamber, wherein selectively supplying a first fluid into the first chamber causes at least a portion of the first fluid and at least a portion of a second fluid supplied into the second chamber to be mixed in the third chamber and dispensed through the fluid outlet.   
     
     
         11 . The pressure-driven metered mixing dispensing pump of  claim 10 , wherein the piston is selectively controllable to move between a first position and a second position. 
     
     
         12 . The pressure-driven metered mixing dispensing pump of  claim 11 , wherein the piston is in the first position when the first fluid is selectively suppled into the first chamber. 
     
     
         13 . The pressure-driven metered mixing dispensing pump of  claim 12 , wherein in the first position, substantially none of a first fluid in the first chamber is directed into the third chamber. 
     
     
         14 . The pressure-driven metered mixing dispensing pump of  claim 13 , wherein in the second position, a volume of the first chamber is expanded and substantially all of the first fluid in the first chamber is directed into the third chamber and a volume of the second chamber is contracted causing the second fluid from the second chamber to enter the third chamber and be mixed in the third chamber with the first fluid from the first chamber. 
     
     
         15 . The pressure-driven metered mixing dispensing pump of  claim 10 , wherein the piston has at least one orifice defined therethrough to eject the at least some of the first fluid from the first chamber into the third chamber. 
     
     
         16 . The pressure-driven metered mixing dispensing pump of  claim 10 , further comprising at least one seal between the housing and the piston to at least partially fluidly isolate the first, second and third from each other. 
     
     
         17 . The pressure-driven metered mixing dispensing pump of  claim 16 , wherein the at least one seal provides a desired bleeding flow rate between the first chamber and the third chamber. 
     
     
         18 . The pressure-driven metered mixing dispensing pump of  claim 10 , further comprising a first one-way valve positioned between the second chamber and the third chamber. 
     
     
         19 . The pressure-driven metered mixing dispensing pump of  claim 10 , wherein the first one-way valve is disposed at least partially within the piston. 
     
     
         20 . The pressure-driven metered mixing dispensing pump as defined of  claim 10 , further comprising a spring configured to move the piston from the second position to the first position.