Patent ID: 6997358

Claim:
A liquid dosing device for fitting to the neck of a squeezable bottle comprising a metering chamber having an inlet or inlets at its inward end to connect its interior to the inside of the bottle and an outlet or outlets at its outward end though which liquid is dispensed, the metering chamber being divided by a freely-moving shuttle into an inlet chamber on the inlet side of the shuttle and an outlet chamber on the outlet side of the shuttle falling to the inlet end of the metering chamber when the bottle is upright, the chamber and shuffle being so configured that, when the bottle is inverted and then squeezed, liquid which is forced in the metering chamber has a main flow component which passes through or around the shuttle and into the outlet chamber but by-passes the inlet chamber behind the shuttle, this flow then being discharged through the outlet(s), and a pilot flow component which is fed into the inlet chamber behind the shuttle but is prevented from passing into the outlet chamber, so that although the shuttle tends to be moved by the viscous drag or impact of the flow of liquid upon it and such movement expands the inlet chamber behind it, the inlet chamber expands only as fast as the pilot flow can fill the expanding inlet chamber such that the ratio of main to pilot flow components determines the rate at which the shuttle will move and hence how much liquid is dispensed before the shuttle reaches the far end of the metering chamber, where it occludes the outlet(s) and prevents any further dispensing of liquid until the process is repeated.