Upright extraction cleaning machine

Abstract

A portable surface cleaning apparatus including a base module for movement along a surface, an upright handle pivotally attached to the base module, a liquid dispensing system including a flexible bladder defining a fluid supply chamber for holding a supply of cleaning fluid, a fluid recovery system including a tank on the base module having a chamber for holding recovered fluid and housing the flexible bladder, and a passageway between the fluid supply chamber and the recovery chamber, whereby the recovery chamber is in communication with the fluid supply chamber and the pressure in the flexible bladder is equalized with the pressure in the tank as the cleaning fluid is dispensed from the supply chamber and the dirty liquid is collected in the recovery chamber. In a further embodiment the tank has an outlet opening in a bottom portion thereof and a drain plug is removably mounted in the outlet opening. In another embodiment a lid mounted on the tank defines an expansion chamber having an inlet opening, an outlet passage, and first and second diverters against which the working air flow reverses direction twice between the inlet opening of the expansion chamber and the tank. In another embodiment the working air conduit includes a manual actuator knob having an over-center linkage mechanism connected to a conversion valve for movement between first and second positions, thereby selectively moving the conversion valve between open and closed positions, whereby fluid communication between the tank and the suction nozzle is selectively opened and closed.