T-shaped cutter tool assembly with wear sleeve

摘要

The wear sleeve in the present cutter tool assembly comprises a rearward split ring portion and an intermediate cylindrical ring portion adjacent a forward shoulder portion. The outer diameter of the wear sleeve intermediate portion and rearward split ring portion is uniform. The wear sleeve is inserted into the bit holder's stepped bore aperture. The split ring portion is radially compressed by the smaller diameter rearward end as the sleeve is hammered and axially displaced into the bit holder. The split ring portion forms frictional contact with the opposite end portion of the aperture. The wear sleeve friction fit can be easily removed manually in the field. The bit holder and cooperating support block are designed to limit the amount of relative yaw between the two members during operation to reduce the overall wear there between. The cutter tool assembly includes a groove having side surfaces that are inclined at least 15 degrees with respect to the horizontal axis and the cutting bit is positioned more aft of the central axis of the support block than prior art designs.