Patent ID: 8414091

Claim:
A crawler for allowing a vehicle to move over the ground, having a track tensioning system, comprising: a) a crawler frame having a bottom; b) at least one drive tumbler supported on the frame; c) a track made of a plurality of connected track shoes and having a ground engaging surface and an inside surface opposite the ground engaging surface, the track being wrapped around the drive tumbler so that a plurality of the shoes are in contact with the drive tumbler, the track passing around the frame; and d) a track tensioning system comprising: i) at least a first and second roller engaging the inside surface of the track with a link in between the rollers and adjacent to the track so that the link can provide engaging support to the track; and ii) a roller positioning structure attached to the frame that can raise the first and second rollers and the link relative to the bottom of the frame to thereby increase the tension of the track and which comprises a holding structure that allows the roller positioning structure to maintain the first and second rollers in a selected position where they are in tensioning engagement with the track while the track is under operational tension.