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Power Transmission Characteristics of a Hydro-Mechanical Transmission

정유압 기계식 변속장치의 동력전달특성

  • Published : 2001.11.01

Abstract

In this paper, power flow characteristics of a hydromechanical transmission(HMT) are investigated using network analysis. The HMT used in this study consist of a hydrostatic unit(HSU), planetary gear sets, clutches and brakes providing forward 4 speeds and backward 2 speeds. Since the HMT power flows showing a closed loop and the HSU efficiency varies depending on the pressure and speed, a systematic approach is required to analyze the power transmission characteristics of the HMT. In order to analyze the closed loop power flow and the HSU power loss which changes depending on the pressure and speed, network model is constructed fur each speed range. In addition, an algorithm is proposed to calculate an accurate HSU loss corresponding to the experimental results. It is found from the network analysis that the torque and speed of each transmission element including the HSU can be obtained as well as direction of the power flow by the proposed algorithm. It is expected that the network analysis can be used in the design of relatively complicated transmission system such as HMT.

Keywords

Network Analysis;HMT;Hydrostatic Unit

References

  1. 서울대학교 정밀기계설계공동연구소, 1995, '무단변속조향시스템의 특성분석 및 제어에 관한 연구,' 국방과학연구소 연구과제 보고서, pp. 260-294
  2. Nomura, K., 1976, 'Study on the Characterisitics of Hydromechanical Transmission,' 三菱重工技報, Vol. 13, No. 3, pp. 456-463
  3. Pichard, J. and Besson, B., 1981, 'Hydrostatic Power Splitting Transmission Design and Application Examples,' Transactions of ASME, Vol. 103, pp. 168-173
  4. Hedman, A., 1985, 'A Method to Analyse Mechanical Transmission System,' Report no.1985-11.08, Division of Machine Elements, Chalmers University of Technology, Goteborg, Sweden, pp. 9-13
  5. Heldman, A., 1989, 'Computer-aided Analysis of General Mechanical Transmission Systems - Some Examples,' Second International Conference on New Development in Powertrain and Chassis Engineering, Strassburg, France, pp. 10-13
  6. 김원, 정순배, 김현수, 1996, '확장된 네트워크기법을 이용한 정유압기계식 변속기의 동력전달특성 해석,' 대한기계학회논문집, 제20권, 제5호, pp. 1426-1435
  7. Misuya, H., Otani, K., Ishino, T., 1994, 'Development of Hydromecharical Transmission for Bulldozers,' SAE 941722
  8. Reppert, R. G., 1987, 'Modern Transmission for Tanks,' Military Technology, pp. 4-24
  9. Ross, W. A., 1972, 'Designing a Hydromechanical Transmission for Heavy Duty Trucks,' SAE 720725
  10. Kress, J. H., 1968, 'Hydrostatic Power-Splitting Transmissions for Wheeled Vehicles - Classification and Theory of Operation,' SAE 680549
  11. Mano, T. and Nomura, K., 1976, 'Hydromechanical Transmissions,' 自動車技術, Vol. 30, No. 9, pp. 765-770
  12. Aitzetmuller, H., 2000, 'Steyr S-matic - The Future CVT System' FISITA, Seoul
  13. Kelly, W. R., 1999, 'A CVT for V8 Engine Application in Passenger Car and Light Trucks,' Int. Congress on Continuously variable Power Transmission CVT'99, pp. 125-135
  14. Kinokami, K. and Miki, K., 1999, 'A Development of HMT for Trucks and Buses,' Int. Congress on Continuously variable Power Transmission CVT'99, pp. 125-135