Modular chemical dispenser and pump for same

Abstract

A chemical dispenser includes a housing, a controller disposed in the housing for operating the chemical dispenser, at least one module bay in the housing and at least one module selectively coupled to the at least one module bay and operatively coupled to the controller for operation with the chemical dispenser. The at least one module may be selected from a plurality of modules each capable of being coupled to the at least one module bay and operating under the control of the controller. A low-maintenance piston pump module for use with the chemical dispenser is also disclosed.

1 .- 13 . (canceled) 
     
     
         14 . A pump module for a modular chemical dispensing system, comprising:
 a module housing;   a piston assembly;   a drive assembly, and   a valve assembly.   
     
     
         15 . The pump module of  claim 14 , wherein the piston assembly comprises:
 a piston housing defining at least two piston cylinders;   at least two pistons each defining a base and a piston head for positioning in respective piston cylinders,   wherein the base of the at least two pistons are operatively coupled to the drive assembly for reciprocating the pistons relative to the piston cylinders.   
     
     
         16 . The pump module of  claim 15 , wherein the piston housing includes at least one guide channel, and each piston including at least one guide rod, wherein the at least one guide rod is configured to be received in a respective guide channel for guiding movement of the pistons. 
     
     
         17 . The pump module of  claim 15 , wherein the drive assembly comprises:
 a motor having a drive shaft coupled to the module housing; and   a gear arrangement operatively coupled to the motor and further operatively coupled to the piston assembly.   
     
     
         18 . The pump module of  claim 17 , wherein the gear arrangement comprises:
 a primary drive gear coupled to the drive shaft of the motor; and   a pair of secondary drive gears configured to be driven by the primary drive gear.   
     
     
         19 . The pump module of  claim 18 , wherein each of the secondary drive gears includes a pin eccentrically positioned relative to a rotational axis of the secondary drive gears, and wherein each pin is configured to be received within a slot in the base of the pistons for moving the pistons. 
     
     
         20 . The pump module of  claim 14 , wherein the valve assembly comprises:
 a valve housing;   a pair of valves; and   a product manifold.   
     
     
         21 . The pump module of  claim 20 , wherein the valve housing comprises:
 a pair of valve heads,   wherein each valve head includes a valve recess,   wherein each valve recess includes an inlet port, an outlet port, and a valve seat, wherein the valve seat is configured to receive one of the pair of valves, and   wherein the inlet and outlet ports of each valve head are in communication with a respective piston cylinder of the piston assembly.   
     
     
         22 . The pump module of  claim 21 , wherein the inlet port includes at least one flow aperture and a valve post. 
     
     
         23 . The pump module of  claim 22 , wherein the inlet port includes a pair of flow apertures with the valve post disposed therebetween. 
     
     
         24 . The pump module of  claim 21 , wherein
 the outlet port includes an annular valve seat.   
     
     
         25 . The pump module of  claim 21 , wherein the product manifold comprises:
 an inlet channel; and   an outlet channel,   wherein the inlet channel is in communication with the inlet port of each of the valve heads, and   wherein the outlet channel is in communication with the outlet port of each of the valve heads.   
     
     
         26 . The pump module of  claim 14 , wherein the piston assembly comprises:
 a piston housing defining at least two piston cylinders; and   a piston having a sliding yoke and two piston heads extending in opposing directions from the sliding yoke, each one of the piston heads being received in a respective piston cylinder,   wherein the sliding yoke is operatively coupled to the drive assembly for reciprocating the piston relative to the two piston cylinders.   
     
     
         27 . The pump module of  claim 26 , wherein one cycle of the piston in the piston assembly is configured to produce two exhaust and two intake cycles. 
     
     
         28 . The pump module of  claim 26 , wherein the piston heads share a common longitudinal axis. 
     
     
         29 . The pump module of  claim 26 , wherein the two piston heads are of different lengths. 
     
     
         30 . The pump module of  claim 26 , wherein the piston heads are hollow and are open to the respective piston cylinder. 
     
     
         31 . The pump module of  claim 26 , wherein the sliding yoke defines an elliptical slot and the drive assembly is movably coupled to the sliding yoke by the elliptical slot. 
     
     
         32 . The pump module of  claim 26 , wherein the piston housing further defines an opening in a yoke cavity, the yoke cavity receives the sliding yoke and the drive assembly engages the piston assembly through the opening. 
     
     
         33 . The pump module of  claim 26 , wherein the piston assembly further comprises:
 a first cylinder head secured in the piston housing and at least partially defining a portion of one piston cylinder; and   a second cylinder head secured in the piston housing and at least partially defining a portion of the other piston cylinder.   
     
     
         34 . The pump module of  claim 33 , wherein each of the first cylinder head and the second cylinder head are in fluid communication with one piston. 
     
     
         35 . The pump module of  claim 33 , wherein the first cylinder head is in fluid communication with a first piston and the second cylinder head is in fluid communication with a second piston, the first piston and the second piston are different pistons. 
     
     
         36 . The pump module of  claim 26 , wherein the valve assembly comprises:
 an inlet valve housing including an inlet valve in fluid communication with at least one cylinder; and   an outlet valve housing including an outlet valve in fluid communication with the at least one cylinder.   
     
     
         37 . The pump module of  claim 36 , wherein each valve is a duckbill valve. 
     
     
         38 . The pump module of  claim 26 , wherein the piston housing defines two cylinders and the piston assembly further comprises:
 a first cylinder head secured in the piston housing and at least partially defining a portion of one piston cylinder;   a second cylinder head secured in the piston housing and at least partially defining a portion of the other piston cylinder; and   the valve assembly comprising:   a first inlet valve housing including a first inlet valve coupled to the first cylinder head and a first outlet valve housing including a first outlet valve coupled to the first cylinder head, and   a second inlet valve housing including a second inlet valve coupled to the second cylinder head and a second outlet valve housing including a second outlet valve coupled to the second cylinder head,   wherein each of first inlet valve, the first outlet valve, the second inlet valve, and the second outlet valve is a duckbill valve.   
     
     
         39 . A pump module for a modular chemical dispensing system, comprising:
 a module housing;   a piston assembly comprising:
 a piston housing defining at least two piston cylinders; 
 at least two pistons each defining a base and a piston head for positioning in respective piston cylinders 
   a drive assembly comprising:
 a motor having a drive shaft coupled to the module housing; and 
 a gear arrangement operatively coupled to the motor and further operatively coupled to the piston assembly; and 
   a valve assembly comprising:
 a valve housing comprising a pair of valve heads; 
 a pair of valves; and 
 a product manifold; 
 wherein each valve head includes a valve recess, 
 wherein each valve recess includes an inlet port, an outlet port, and a valve seat, 
 wherein the valve seat is configured to receive one of the pair of valves, 
 wherein the inlet and outlet ports of each valve head are in communication with a respective one of the piston cylinders, and 
   wherein the base of the at least two pistons are operatively coupled to the drive assembly for reciprocating the pistons relative to the piston cylinders.