AN INVESTIGATION INTO MICRO- AND MACROGEOMETRIC DESIGN OF PISTON/CYLINDER ASSEMBLY OF SWASH PLATE MACHINES
Keywords:
axial piston machine, piston cylinder assembly, pressure field, friction force, gap flow, surface roughness, friction force measurementAbstract
This paper presents main results of an investigation of the tribological system formed by the piston/cylinder assem-bly of swash plate axial piston machines. Main focus has been given to the influence of a piston macro and micro geom-etry variation on energy dissipation generated by piston/cylinder assembly. Using the simulation tool CASPAR, which has been developed at the Institute for Aircraft Systems Engineering, an optimization of the piston shape has been realized to achieve minimum energy dissipation in a wide range of operating parameters of the axial piston machine. Micro ge-ometry stands for surface roughness here. Its influence has been investigated within a second task especially in the area of low speed, where full lubrication is not achievable and therefore mixed friction occurs. For the investigation a special friction force measurement test rig has been developed, which has also been used for verification of the simulation tool CASPAR.
Downloads
References
Ezato, M. and Ikeya, M. 1986. Sliding Friction Char-acteristics between a Piston and a Cylinder Starting and Low-Speed Conditions in the Swashplate-Type Axial Piston Motor. 7th International Fluid Power Symposium, Bath, UK.
Fang, Y. and Shirakashi, M. 1995. Mixed lubrication characteristics between the piston and cylinder in hydraulic piston pump-motor. ASME Transactions, Journal of Tribology, vol. 117, pp. 80-85.
Ivantysynova, M. 1999. Ways for Efficiency Improve-ments of Modern Displacement Machines. Proc. ofFluid Power, Tampere, Finland, pp.77-92.
Ivantysynova, M. 1999. A new approach to the design of sealing and bearing gaps of displacement ma-chines. Proc. JHPS International Symposium on Fluid Power, Tokyo, Japan.
Ivantysyn, J. and Ivantysynova, M. 2000. Hydrostatic Pumps and Motors, Principles, Designs, Perfor-mance, Modelling, Analysis, Control and Testing. Academia Books International, New Delhi. (ISBN -81-85522-16-2)
Ivantysynova, M.; Grabbel, J. and Ossyra, J.-C. 2002. Prediction of Swash Plate Moment Using the Simulation Tool CASPAR. 2002 International Me-chanical Engineering Congress and Exposition, IMECE2002-39322, New Orleans, Louisiana, USA.
Ivantysynova, M. and Huang, C. 2002. Investigation of the Gap Flow in Displacement Machines Consid-ering Elastohydrodynamic Effect. 2002 The Fifth JFPS International Symposium on Fluid Power, Nara 2002. Nara, Japan.
Kleist, A. 1997. Design of hydrostatic bearing and seal-ing gaps in hydraulic machines- A new simulation tool. Proc. of the 5th Scandinavian International Conference on Fluid Power ICFP, Linköping, Swe-den, pp. 157-169.
Kleist, A. 2002. Berechnung von Dicht- und Lager-fugen in hydrostatischen Maschinen. Institute for Fluid Power Drives and Controls (IFAS), University of Aachen (RWTH), Aachen, Germany, Shaker Verlag Aachen, ISBN 3-8322-0279-X.
Lasaar, R. 2000. The influence of the microscopic and macroscopic gap geometry on the energy dissipation in the lubricating gaps of displacement machines. Proc. of 1st FPNI-PhD Symposium Hamburg 2000, ISBN 3-00-006510-5, Hamburg, Germany, pp. 101-116.
Lasaar, R. and Ivantysynova, M. 2001. Gap geometry variations in displacement machines and their effect on the energy dissipation. Proc. of the 5th International Conference on Fluid Power Transmission and Control, Hangzhou, China, pp. 316-322.
Lasaar, R. and Ivantysynova, M. 2002. Advanced gap design – basis for innovative displacement ma-chines. Proc. of 3rd IFK (Internationales Flu-idtechnisches Kolloquium), ISBN 3-8265-9901-2, Aachen, Germany, pp. 215-230.
Lasaar, R. 2003. Eine Untersuchung zur mikro- und makrogeometrischen Gestaltung der Kolben/-Zylinderbaugruppe von Schrägscheibenmaschinen. Dissertation TU Hamburg-Harburg, ISBN 3-18-336401-8, VDI-Verlag, Düsseldorf.
Manring, N. D. 1999. Friction forces within the cylin-der bores of swash-plate type axial-poston pumps and motors. Journal of dynamic systems, measure-ment and control, Vol. 121, pp. 531-537.
Olems, L. 2000. Investigations of the temperature be-haviour of the piston cylinder assembly in axial pis-ton pumps. International Journal of Fluid Power, Vol. 1, No.1, pp. 27-38.
Renius, K. T. 1974. Untersuchungen zur Reibung zwischen Kolben und Zylinder bei Schräg-scheiben-Axialkolbenmaschinen. VDI Forschungsheft 561, Düsseldorf: VDI-Verlag.
Tanaka K.; Kyogoku K. and Nakahara, T. 1999. Lubrication characteristics on sliding surfaces be-tween piston and cylinder in a piston pump and mo-tor (Effects of running-in, profile of piston top and stiffness). JSME International Journal, Series C (Mechanical Systems, Machine Elements and Man-ufacturing), Vol. 42, No. 4, pp. 1031-1040.
Wieczorek, U. and Ivantysynova, M. 2002. Computer Aided Optimization of Bearing and Sealing Gaps in Hydrostatic Machines - the Simulation Tool CAS-PAR. International Journal of Fluid Power, Vol. 3, No. 1, pp. 7-20.