To improve fluid compression efficiency by suppressing deformation of a turning scroll by high-pressure fluid.

Compressed air delivered from the delivery port 8 of a first-stage compressor 2 as a front stage is introduced into a closed space 16 positioned in the back side of the turning scroll 19 of a second-stage compressor 14 as a next stage. Also, compressed air delivered from the delivery port 22 of a second-stage compressor 14 as a front stage is introduced into a closed space 31 positioned in the back side of the turning scroll 34 of a third-stage compressor 29 as a next stage. Therefore, pressure on the back sides of the turning scrolls 19, 34 is increased by the compressed air, and a pressure difference between compression chambers 20, 35 and the closed spaces 16, 31 is reduced. Accordingly, it is possible to suppress the deformation of the plate bodies 19A, 34A of the turning scrolls 19, 34 and improve the compression efficiency.

COPYRIGHT: (C)2011,JPO&INPIT