Vane compressor

The invention provides a vane compressor which hardly causes power loss and backflow of refrigerating gas and the like. The vane compressor includes shells (1, 3, 5), a drive shaft (8), a rotor (15), vanes (17) and a backpressure supply device. The backpressure supply device includes an upper channel (4c), a lower channel (4d) and a rotary channel (8b). The upper channel is formed on a second partition wall (3a) and extends from a discharge chamber (10) and leads to a shaft hole (4b). The lower channel is formed in the second partition wall (3a) and is communicated with a backpressure chamber (15d) of a compression stage. The rotary channel is formed in the drive shaft and the upper channel and the lower channel are communicated with each other intermittently according to a phase position of the drive shaft in a rotation direction or a rotation angle of the drive shaft. The lower channel includes a buffer chamber (4e) configured to lead to the shaft hole and be communicated with the rotary channel and a discharge hole (4f) configured to extend from the buffer chamber and lead to a second face (4a). A sealing ring (23) is arranged between the shaft hole and the drive shaft so as to seal the buffer chamber from the second face.