Dispensers, refill units and pumps having suck-back features

Abstract

Exemplary embodiments of dispensers and refill units having suck-back mechanisms are disclosed herein. An exemplary refill unit includes a container, a pump connected to the container, and an outlet passage. The outlet passage includes a first cylindrical portion and a second portion. The diameter of the second portion is larger than the diameter of the first cylindrical portion. An inline suck-back valve is located in the in the outlet passage. The inline-suck-back valve moves within the first cylindrical portion and the second portion of the outlet passage. Movement of the inline suck-back valve in a first direction while the inline suck-back valve is located within the first cylindrical portion causes fluid in the outlet passage to be drawn back into the outlet passage.

We claim: 
     
         1 . A refill unit comprising:
 a container;   a pump connected to the container; and   an outlet passage;   the outlet passage includes a first cylindrical portion and a second portion;   wherein the diameter of the second portion is larger than the diameter of the first cylindrical portion;   an inline suck-back valve located in the in the outlet passage;   wherein the inline-suck-back valve moves within the first cylindrical portion and second portion of the outlet passage; and   wherein movement of the inline suck-back valve in a first direction while the inline suck-back valve is located within the first cylindrical portion causes fluid in the outlet passage to be drawn back into the outlet passage.   
     
     
         2 . The refill unit of  claim 1  wherein the pump is a foam pump. 
     
     
         3 . The refill unit of  claim 1  wherein the refill unit is for an under-counter mount refill. 
     
     
         4 . The refill unit of  claim 1  further comprising a biasing member to bias the suck-back valve toward the pump. 
     
     
         5 . The refill unit of  claim 4  wherein the biasing member compresses when fluid is forced through the outlet by the pump. 
     
     
         6 . The refill unit of  claim 1  wherein the pump is located below the container. 
     
     
         7 . A refill unit comprising:
 a container;   a pump connected to the container;   an outlet passage having a first cylindrical portion and a second portion;   an inline suck-back valve located in the in the outlet passage;   wherein fluid flowing from the pump causes the inline suck-back valve to move away from its rest position; and   wherein when fluid stops flowing out of the pump, the inline suck-back valve moves back to its rest position and draws residual fluid in the outlet passage back.   
     
     
         8 . The refill unit of  claim 7  wherein the first cylindrical portion has a smaller diameter than the second portion. 
     
     
         9 . The refill unit of  claim 7  further comprising an outlet tube extending upward from the inline suck-back valve. 
     
     
         10 . The refill unit of  claim 7  further comprising a spring for biasing the suck-back to its rest position. 
     
     
         11 . The refill unit of  claim 10  wherein the spring compresses to allow fluid to flow past the suck-back valve and expands to move the suck-back valve to its rest position. 
     
     
         12 . The refill unit of  claim 7  wherein the refill unit is an under-counter mount refill unit. 
     
     
         13 . The refill unit of  claim 7  wherein the pump is located below the container. 
     
     
         14 . The refill unit of  claim 7  further comprising one or more guide ribs to guide the suck-back valve. 
     
     
         15 . The refill unit of  claim 7  further comprising an outlet nozzle having a drip catcher located proximate the outlet nozzle. 
     
     
         16 . A refill unit comprising:
 a container;   a foam pump secured to the container;   an outlet passage downstream of the foam pump;   an inline suck-back valve located in the outlet passage;   the inline suck-back valve having a sealing member;   a first portion of the outlet passage engages with the sealing member and fluid cannot pass by the sealing member when the sealing member is located in the first portion of the outlet passage; and   an outlet;
 wherein movement of the sealing member in the first outlet passage toward the foam pump draws fluid away from the outlet. 
   
     
     
         17 . The refill unit of  claim 16  further comprising an outlet tube located between the outlet passage and the outlet. 
     
     
         18 . The refill unit of  claim 16  wherein the refill unit is an under counter mount refill unit. 
     
     
         19 . The refill unit of  claim 16  further comprising a biasing member to bias the sealing member toward to foam pump. 
     
     
         20 . The refill unit of  claim 19  wherein the biasing member compresses to let fluid flow from the foam pump to the outlet and expands to suck fluid back from the outlet when the foam pump is at rest. 
     
     
         21 . A dispenser system:
 a container;   a pump secured to the container;   an outlet passage downstream of the pump;   an inline suck-back valve located in the outlet passage;   the inline suck-back valve having a sealing member;   a first portion of the outlet passage engages with the sealing member and fluid cannot pass by the sealing member when the sealing member is located in the first portion of the outlet passage; and   an outlet;
 wherein movement of the sealing member in the first outlet passage toward the foam pump draws fluid away from the outlet. 
   
     
     
         22 . The refill unit of  claim 21  wherein the outlet passage is a foam outlet passage. 
     
     
         23 . The refill unit of  claim 21  wherein the outlet passage is a liquid outlet passage. 
     
     
         24 . The refill unit of  claim 21  wherein the outlet passage is an air outlet passage.