Patent ID: 6135320
Filing Date: 2000-10-24
Classification: A47K

Abstract:
A liquid dispenser comprising:A) a container forming a reservoir that contains a fluid, being collapsible between expanded state, in which the reservoir has a first volume, and a contracted state, in which the reservoir has a second volume less than half the first volume;B) at least one flow controller, each of which comprises:i) a conduit that so communicates with the interior of the reservoir that the container tends to expel the liquid through the conduit when the container collapses from its expanded to its contracted;ii) an electric valve operable by application of control signals thereto to switch between an open state, in which the valve permits fluid flow through the conduit, and a closed state, in which it prevents fluid flow through the conduit; andiii) a sensor circuit operable to sense the presence of objects in a target region and apply control signals to the electric valve control flow of liquid through the conduit in response to at least one predetermined characteristic of the sensed object; andC) a spring that so bears against the container as to urge it toward its contracted state with a force that varies by less than 20% between the expanded and contracted states and causes a reservoir pressure that exceeds ambient by more than 10 psi.