1.  Field of the Invention
The present invention relates to a sliding-vane rotary compressor suitable for use in an automobile air conditioning system, for example. 
2.  Description of the Related Art
There has been a growing demand for a compact sliding-vane rotary compressor.  With this demand in view, the present applicant has proposed one such compact compressor as disclosed in Japanese Patent Application No.  62-241019. 
The disclosed compressor, as reillustrated here in FIG.  3 of the accompanying drawings, includes a cylinder 1, two side blocks 7a, 7b secured to opposite ends of the cylinder 1, and two heads 11a, 11b directly connected to the side blocks 7a, 7b.  With this construction, the compressor, as distinct from other conventional ones, has no structural component corresponding to a shell.  A rotor 2 fixedly mounted on a drive shaft 4 is rotatably received in the cylinder 1 so as to define therebetween two operating compartments 3a, 3b.  The rotor 2 carries thereon a plurality of radially movable vanes so that the cylinder 1, the rotor 2 and the vanes define therebetween a plurality of compression chambers which vary in volume with each revolution of the rotor 2.  One of the side blocks 7a and the corresponding head 11a define therebetween a low pressure chamber 17 through which a working gas is introduced into the operating compartments 3a, 3b.  The gas after having been compressed in the compression chambers is then fed into a high pressure chamber 18 which is defined by and between the other side block 7b and the mating head 11b.  The gas, as its flows through the high pressure chamber 18 toward a discharge port 16, is separated from an lubricating oil.  The oil thus separated is held in a lower portion of the high pressure chamber 18 and continuously fed on occasion to sliding surfaces of the rotor 2, the vanes and other movable parts. 
In the compressor of the foregoing construction, the high pressure chamber must be large enough to hold a great amount of oil for not causing seizing of the sliding surfaces.  Due to this large high pressure chamber, a substantial reduction in axial dimension or size of the compressor is difficult to obtain.