PURPOSE: To provide a compressor which is simple in structure and reduced in size by a method wherein a rotor in a circle in cross section is rotatably contained in an eccentric position in a circular case, and a blade having two ends making slide contact with the inner wall surface of the circular case is slidably engaged with a slide groove formed in the rotor and extending through the center thereof.

CONSTITUTION: A suction port 2 and a delivery port 3 are formed in an inner wall surface 1A of a circular case 1 having an inner periphery being round, and a rotor 4 is rotatably contained inside the circular case 1 and eccentrically to a case center C1. A slide groove 5 is formed in the rotor 4 in a manner to extend through a center C2 of the rotor and a blade 6 is reciprocatively engaged therewith. The blade 6 is formed such that resilient substances 8 and 8, e.g. soft plastic, are joined with both ends of one plate, and the resilient substance 8 is brought into slide contact with the inner wall surface 1A of the case 1. Through rotational drive of the rotor 4, a space on the suction port 2 side is gradually expanded to suck fluid therein, and meanwhile a space on the delivery port 3 side is gradually contracted to deliver the fluid.