The Graphic Method of Modified Wrap Scroll Compressor

After aulyzing the interaction betlreen the cutter and the inolute in machining processes of scroll wraps and its influence on the discharge angle and the compresiion ratio, a new method suggested by present authors for modification of the inTolute wrap of the scroll compressor is presented in this paper. The new method, different from any other method which has eTer been published, includes graphical ud analytical solution, and the equation of the discharge angle of a pair of modified scroll wraps is alao ghu. This definition of the IJlodified ugle u well u ih sen1e -is introduced by· the author for the first time. After .modification· by the new method, the discharge angle sometimes may become 2 ll and the top clearance may turn into zero. Therefore, a higher compression r.atio and cotnpreuor Tolumetric efficiency canbe achieTed. NOYENCLATtlli.E Compression ratio of scroll compressor N Number of crescent gaa pocket generated b1 a pair of acroll members 6 Rotational angle of crank shaft · 6 ' Discharge ID.gle k Adiabatical inde1 of gas d Diameter of cutter p Scroll pitch t Scroll thickness a Radius of the base circle of inYolute Ra. Rotational radiue of crank INTRODUCTION The ecroll compreasor ia a new type of TOlumetric ~ompreeaor with high-efficiency. energy-saTing , materialsaTing and lownoise characteristica. It can be widely used in many industrial fields auch aa air conditioning, refrigeration, ucuum-pumping ud gu compreuion ,and it can be e1pected to partly replace the other types of mini-compressor in the future. A key and '''' important problem in the design of such a compressor is the