Automated fluid dispenser

An automatic fluid dispenser comprising:

• a liquid soap reservoir;
• a soap dispensing fixture;
• a pump mechanism including a housing defining a pump chamber having an inlet coupled to the liquid soap reservoir and an outlet coupled to the soap dispensing fixture, a first check valve mounted in the inlet of the pump chamber for allowing liquid soap flow only into the pump chamber from the reservoir, and a second check valve mounted in the outlet for allowing liquid soap flow only out of the pump chamber to the soap dispensing fixture, a piston positioned within a bore in the housing for reciprocating motion between a first position in which the pump chamber has a volume and a second position in which the volume of the pump chamber is reduced, the pump mechanism including a biasing element biasing the piston into the first position;
• a conduit coupled to the bore and coupled to a pressurized water source, the conduit directing pressurized water from the pressurized water source onto the piston;
• a valve carried by the conduit and movable between an open position in which pressurized water from the pressurized water source moves the piston to the second position, and a closed position stopping the pressurized water;
• a water bleed coupled to the bore between the piston and the valve;
• and
• a sensor for actuating a solenoid to move the valve to the open position, the valve being normally biased to the closed position, the sensor being positioned proximate the fixture.