Patents Assigned to Product Research and Development, Inc.
  • Patent number: 6120399
    Abstract: The invention is a secondary, or driven, element suitable for use as one element of a three-element continuously variable transmission comprising a primary drive sheave, a V-belt, and the secondary drive sheave. Both sheaves have variable pitch diameters. The pitch diameter of the primary split sheave increases with increasing rotation rate, and the pitch diameter of the secondary split sheave increases as the torque applied to the load increases. The moveable portion of the driven sheave is fitted with a cam in the form of a helix in a hollow cylinder. A roller-type cam follower is mounted perpendicular to the sheave rotational axis on a stub shaft, or spider, that extends radially from the post, an axial extension of the fixed sheave portion. A spring biases the driven sheave portions toward maximum pitch diameter. Increased torque tends to rotate the moveable sheave portion with respect to the shaft and fixed sheave.
    Type: Grant
    Filed: June 7, 1999
    Date of Patent: September 19, 2000
    Assignee: Product Research and Development, Inc.
    Inventors: Shane Okeson, Richard K. Olson, Brian Eck, Michael Gunderson