초록 ▼

This invention relates to an apparatus for positioning a bearing surface relative to a track. The invention, in one embodiment, includes a rotatably mounted drive mechanism which is provided with a plurality of radially oriented tracks. The drive mechanism preferably comprises a pair of parallel dri

This invention relates to an apparatus for positioning a bearing surface relative to a track. The invention, in one embodiment, includes a rotatably mounted drive mechanism which is provided with a plurality of radially oriented tracks. The drive mechanism preferably comprises a pair of parallel drive disks with co-linear, radial tracks having tooth-like formations arranged therein. A movable sheave segment is mounted between each set of co-linear tracks. Each sheave segment comprises two pair of engagement blocks, one pair for each track and an independent multi-element cam lock. Tooth formations on the engagement blocks provide formations for locking each sheave segment into place in the toothed track. Each sheave segment\s bearing surface is engaged by an endless belt when the drive mechanism traverses through a predetermined arc of rotation but is disengaged from the drive belt when outside the predetermined arc of rotation. The multi-element cam lock associated with each sheave segment is forced by belt pressure to rigidly bias a sheave segments\engagement blocks against the tooth-like formations in the track. Springs are also provided to resiliently bias the engagement blocks into engagement with the track\s tooth-like formations so that the sheave segments are lightly held in place even when out of engagement with the drive belt.

대표청구항 ▼

In a variable ratio drive mechanism, the combination comprising: a rotatably mounted drive mechanism having a plurality of radially elongated tracks with tooth like formations therein; an endless drive member; a plurality of movable sheave segments mounted in association with a track, each sheave se

In a variable ratio drive mechanism, the combination comprising: a rotatably mounted drive mechanism having a plurality of radially elongated tracks with tooth like formations therein; an endless drive member; a plurality of movable sheave segments mounted in association with a track, each sheave segment including cam/bearing means and toothed means, said cam/bearing means having multiple camming surfaces associated with each said toothed means and independently movable radially relative to each said toothed means, said cam/bearing means engaged by said endless drive member when said drive mechanism is outside a predetermined arc of rotation, to rigidly bias said toothed means against said track; and means associated with each said sheave segment for resiliently biasing said toothed means into engagement with said track.