Liquid dosing devices

Abstract

A device for dosing a liquid product into a flow of liquid, the device comprising a dosing chamber ( 6 ) for the liquid product, said chamber having a porous wall ( 26 ) through which the liquid product is transported when the porous wall is within the flow of liquid but which retains the liquid product within the dosing chamber when the liquid flow is removed, and a constant head construction ( 14,30,36 ) such that the hydrostatic pressure of the product in the chamber ( 6 ) is substantially independent of the head of liquid product above it.

1 . A device for dosing a product (P) into a flow of liquid (F), the device comprising a chamber ( 6 ) for the product, said chamber ( 6 ) having a porous wall ( 26 ) through which the product (P) is transported when the porous wall ( 26 ) is within the flow of liquid (F) but which retains the product (P) within the dosing chamber ( 6 ) when the liquid flow (F) is removed, characterized in that the product is fluent and there is a constant hydrostatic head in the chamber ( 6 ).  
     
     
         2 . A dosing device according to  claim 1 , wherein the device includes a reservoir ( 10 ) of the fluent product, the reservoir being closed at its top end, and the device includes an air supply ( 30 ) through which air can enter the lower end of the reservoir ( 10 ) or the chamber ( 6 ).  
     
     
         3 . A dosing device according to  claim 2 , comprising means ( 14 ′) for accommodating liquid displaced as a result of expansion due to a rise in temperature of an air pocket ( 36 ) trapped at the closed upper end of the reservoir ( 10 ).  
     
     
         4 . A device according to any one of the preceding claims, for dosing a liquid product (P) into a receiver (B) in conjunction with a liquid flow (F) into said receiver (B), comprising means ( 8 ) for suspending the dosing chamber ( 6 ) within the receiver (B) in the path of said liquid flow (F).  
     
     
         5 . A dosing closure for a container, e.g. a bottle, the closure comprising a chamber supplied with a fluent product from the container, said chamber having a porous wall through which the fluent product is transported only when the porous wall is disposed within a flow of liquid, the closure comprising also means for maintaining a constant hydrostatic pressure of said fluent product at said wall.  
     
     
         6 . A container for a liquid product, the container comprising an outlet and a closure according to  claim 5  installed in said opening.  
     
     
         7 . A container according to  claim 6 , wherein the chamber is open to the interior of the container so that it can be filled by inverting the container.  
     
     
         8 . A dosing device according to any one of  claims 1  to  5  or a container according to  claim 6  in combination with a liquid product comprising a component that has an affinity for the flowing liquid into which it is to be dispensed.