(57) A spray coating apparatus (10) for applying a paint composed of a controlled mixture
of two liquid components. A first gear pump (32) is disposed in a spray booth (30)
and pumps the first component to an applicator (14). A second gear pump (36) in the
spray booth (30) pumps the second component to the applicator (14). A manifold (44)
is disposed between the two gear pumps (32, 36) and the applicator (14) for mixing
the two paint components. A variable speed motor (16, 20) controls the rate of fluid
pumped by each of the gear pumps (32, 36). Each motor (16, 20) includes an encoder
(27, 29) sending feedback signals to an adjustor module (24) which compares the instantaneous
speed of each motor (16, 20) with a reference speed, then adjusts the instantaneous
speed of each motor (16, 20) to conform with the reference speeds thereby adjusting
the ratio between the volumetric flow rates of the first and second components with
respect to a reference ratio.
|
|
