PURPOSE: To improve the suction efficiency of a pump chamber by forming a suction hole onto the housing of the pump chamber, in a compressor in which a reciprocating vane is springily attached onto a rotary web plate.

CONSTITUTION: A web plate hub part 145 is arranged integrally onto the outer periphery of a shaft 125, and a web plate 143 having the form bent into wave form is installed onto the periphery. On the both sides of the web plate 143, a vane 151 which is closely attached onto the outer surface of the web plate 143 and nips the web plate 143 is arranged. A suction port 153 for introducing the working fluid into a pump chamber 243 is formed in the vicinity of the vane groove 245 of a pump housing 113. With such constitution, the suction port 153 can be formed so that the suction port 153 is closed when the capacity of the pump chamber 243 becomes max., and the suction efficiency of the pump chamber 243 can be improved.