Scroll compressor having a gradually changing tip clearance

摘要

A scroll compressor performing three-dimensional compressions, which can optimize a tip clearance in operation while considering a thermal expansion and a pressure deformation and which can reduce a compression leakage to improve a compression efficiency thereby to realize a high performance. The leading end faces (13c and 13d) and the bottom face of a spiral wrap (13b) have a step portion (13e), and the wrap height on the outer circumference side of the spiral wrap (13b) is made larger than that on the inner circumference side wrap height. The spiral wrap (13b) on the inner circumference side with respect to the step portion (13e) is stepwise or continuously made gradually lower toward the center side of the spiral wrap (13b), and the tip clearance (&Dgr;i) of the spiral wrap on the inner circumference side with respect to the step portion (13) is made gradually larger toward the center side of the spiral wrap (13b).