Abstract: A rotary, sliding vane compressor is provided with means for supplying a relatively small, predetermined quantity of an incompressible fluid, such as lubricating oil, underneath the vanes. The fluid is injected at a point while the vanes are collapsing within the vane pockets formed within the rotor and is trapped underneath the vane during its movement to the contact point thereby resisting the collapse of the vane so as to hold the vane tip in continuous engagement with the stator surface in the compression cavity. The means for supplying the fluid underneath said vanes includes a device for interrupting flow of lubricant from a sump to the interior of the compressor housing thereby controlling or metering the lubricant and also preventing reverse rotation of the compressor rotor caused by oil pressure under the vanes forcing the vane tips to follow the curvature of the cylinder wall in a backward direction.

Abstract: A rotary sliding vane compressor having means for biasing the vanes outwardly. Such means include a resilient element located in the lower portion of the vane slot and engaging a convexly shaped edge on the vane. The flexing action of the resilient member insures that the vanes will be moved outwardly during the expansion phase of rotor travel.