Abstract: A cleaning apparatus (10) for removing residual paint from flow passages in a spray painting system comprises a flow passage (12) for conveying paint to a spraying device (14) and a manifold (16) defining a plurality of individual inlets (17) into the flow passage. At least two different paints are supplied to the manifold through the inlets. A solvent supplier (20) supplies a variable pressure and variable volume flow of solvent to the manifold (16) during a cleaning cycle to remove residual paint from the manifold and the flow passage (12) after a completed painting cycle to prepare for a new cycle. The assembly is characterized by including a constant volume flow controller (22) for maintaining a constant volume flow of solvent upstream of the manifold (16) independent of solvent pressure fluctuations.

Abstract: A flushable, positive displacement, gear-type metering pump assembly comprising: a pump housing with inlet and outlet chambers; cylindrical gears disposed within the pump housing adapted to rotate such that gear faces mesh and form a seal which separates inlet and outlet chambers, the gears being adapted to carry metered amounts of fluid between the gear faces and the wall of the pump housing from the inlet chamber to the outlet chamber; channel means for conveying fluid into the inlet chamber and directing the fluid against the gear faces exposed to the inlet chamber; channel means for conveying fluid from the inlet chamber to valve means; channel means for conveying fluid from the valve means to the outlet chamber; valve means adapted to be closed when the pump assembly is in a metering mode such that fluid may pass from the inlet chamber to the outlet chamber only by being carried between the gear faces and the wall of the pump housing and in an open mode when the pump is in a flushing mode such that fluid