Trench digging apparatus and bearing therefor

摘要

A trench digging apparatus comprising a cutter wheel with picks projecting from the outer periphery thereof. An electric drive motor is provided to rotate the cutter wheel about a substantially horizontal axis. The cutter wheel is supported by a support frame which is pivoted to a basic framework of the apparatus by spherical and eccentric hinge bearings. These hinge bearings allow a limited amount of movement about a vertical axis as well as pivotal movement about a horizontal axis. The movement about a vertical axis allows the cutter wheel to turn or be oscillated to free the apparatus, correct for crabbing or enhance cutting, and the movement about the horizontal axis enables the trench depth to be varied.