Patent ID: 6471498
Filing Date: 2002-10-29
Classification: F04C

Abstract:
A fluid machinery comprising:a stationary spiral having an inner engaging surface that rises spirally from its inner periphery to its center and has a stepwise sectional shape; a moving spiral having an outer engaging surface that rises spirally from its outer periphery to its center and has a stepwise sectional shape, the moving spiral being rotatable about an axis relative to the stationary spiral; a plurality of working chambers formed between the outer engaging surface of the moving spiral and the inner engaging surface of the stationary spiral, the working chambers decreasing in volume as the working chambers approach toward the center of the stationary spiral; pushing means for pushing the moving spiral toward the stationary spiral along the axis; a spiral sealing member provided between the inner engaging surface of the stationary spiral and the outer engaging surface of the moving spiral, for sealing and isolating the working chambers from one another, wherein the pushing means urges the outer engaging surface of the moving spiral against the inner engaging surface of the moving spiral to improve sealing and isolate the working chambers from one another during normal operation, and wherein the pushing means allows the moving spiral to move away from the stationary spiral against the urging of the pushing means when the working chambers are at an abnormally high pressure to reduce pressure in the working chambers.