A continuously-variable transmission (CVT) with a transaxle traction design is reported. The CVT will improve fuel economy of an internal combustion engine by 30% to 50%. Many of its advantages remain when used in electric cars, and the CVT is practically essential for flywheel or hybrid vehicles. A transaxle traction CVT can be built by combining positive drive to each wheel and eliminating a separate differential. It is estimated that a CVT will cost less than a four-speed or five-speed manual gearbox plus differential and considerably less than other automatic and differential combinations. Except at very light loads, the transaxle traction CVT's efficiency averages at least 92% throughout the transmission ratio range. A ratio range of 9 to 1 is easily available without regeneration or multimoding gears. Shock loading capacity and maintenance-free life can exceed present transmission designs. Performance and efficiency advantages of the transaxle traction CVT are obtainable almost independent of power source or rating, car weight, and hybrid configuration. For electric vehicles, the design allows high performance with phase-controlled A.C. motors or field-controlled D.C. motors; armature choppers are not needed. Size and weight of the transaxle traction CVT are about the same as those of existing automotive design.

  • Supplemental Notes:
    • Also published in HS-028 833 (SAE-SP-465), "Advanced Gas Turbine Systems for Automobiles," Warrendale, Pennsylvania, 1980, p 39-45. Presented at SAE Congress and Exposition, Detroit, 25-29 February 1980.
  • Corporate Authors:

    Society of Automotive Engineers (SAE)

    400 Commonwealth Drive
    Warrendale, PA  United States  15096
  • Authors:
    • Kraus, C E
  • Publication Date: 1980

Media Info

  • Pagination: 7 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00391488
  • Record Type: Publication
  • Source Agency: National Highway Traffic Safety Administration
  • Report/Paper Numbers: SAE 800102, HS-028 837
  • Files: HSL, USDOT
  • Created Date: Dec 30 1984 12:00AM