Performance, driveability and NVH characteristics of a vehicle are altered when the hydraulic torque converter is bypassed with a mechanical clutch device in an effort to increase the overall efficiency of the transmission. To better illustrate and explain some of the behavior of such systems, a theoretical investigation of a torque converter with a centrifugal bypass (lock-up) clutch is presented. Computer-based simulations demonstrate how the lock-up characteristics of the clutch affect the torsional vibrations and the tip-in response of the drivetrain. In particular, the bypass clutch slip capacity is shown to be responsible for self-excited oscillations if "negative damping" is present. In addition, the dynamic responses of open, locked and slipping drivetrains are investigated with regard to firing torque transmissibility and sudden changes in throttle. Comparisons with instrumented vehicle results are also presented.

  • Supplemental Notes:
    • Published in SP-619, Passenger Car Transmissions.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Tsangarides, M C
    • Tobler, W E
  • Publication Date: 1985-2

Media Info

  • Features: Appendices; Figures; References;
  • Pagination: n.p.

Subject/Index Terms

Filing Info

  • Accession Number: 00399153
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: SAE 850461, HS-038 862
  • Files: HSL, USDOT
  • Created Date: Sep 30 1985 12:00AM