Internally geared screw machines with ported end plates

10th International Conference on Compressors and their Systems

Read, M.G.^1 ; Smith, I.K.^1 ; Stosic, N.^1

Centre for Compressor Technology, City University of London, Northampton Square, EC1V 0HB, United Kingdom^1

关键词: Geometrical analysis;    Helical gearing;    Inner and outer rotors;    Parallel axes;    Rotor profiles;    Screw configurations;    Screw machines;    Working chambers;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/232/1/012058/pdf
DOI  :  10.1088/1757-899X/232/1/012058

来源: IOP

【 摘 要 】

It is possible to design cylindrical helical gearing profiles such that an externally lobed inner gear rotates inside an internally lobed outer gear while maintaining continuous lines of contact between the gears. The continuous contact between the inner and outer rotors (analogous to the main and gate rotors in a conventional screw machine) creates a series of separate working chambers. In this type of machine the rotors have parallel axes of rotation, and if both rotors are free to rotate about their own axes, these axes can be fixed in space. The use of ported end plates is proposed to control the period during which fluid is allowed to enter or leave the working chambers of the internally geared screw machine. As with conventional screw machines, these internally geared rotors can then be used to achieve compression or expansion of a trapped mass of fluid, and the machine geometry can be designed in order to optimise performance for particular applications. This paper describes the geometrical analysis of some simple rotor profiles and explores the effect on rotor torques for particular applications of this novel screw configuration.