Paint system interlock

A paint system comprises a flexible bag (24) for paint, the bag having a sealable opening (40); a machine (10), adapted to receive and squeeze the bag of paint; a tube (60) for releasable connection to said opening; and means (70) to connect a paint applicator (80) at the other end of said tube, adapted to receive paint from said bag, through said tube, when the bag is squeezed by the machine. A bellows (22) is in the container. A pump (28) is adapted to pressurise the bellows with fluid so as to squeeze the bag. The machine comprises an open container (12), a lid (14) pivoted thereto and a handle arrangement (16). The handle includes a latch (17) to hold the lid closed. The handle does not stay in the closed position unless the lid is closed because, if it is open when the machine is operated, the lid has means (27) to move the handle to an open position. The handle has latch means (116) disabling the pump unless the handle is, and remains, in its fully closed position.