A floor treatment machine with a torque limiter assembly between a rotating drive linkage and a rotating head for treating a floor surface. The torque limiter assembly includes engaged plates that disengage upon the application of a predetermined torque created when the head slows or stops rotating because of a floor obstruction. Upon the disengagement of the plates, the drive linkage continues to rotate and is less likely to sustain damage from the effect of the floor obstruction on the rotation of the head. The plates may engage each other through a configuration of cooperating teeth and notches. Alternatively, a rotating head can be provided with a built-in torque limiter assembly. This head can be attached to various floor treatment machines. The amount of predetermined torque that causes the plates to disengage may be adjusted as needed for varied floor conditions.

A power-operated and hand steerable machine for stripping linoleum, tile, mastic, grout, adhesive and the like from a floor and also for re-surfacing the floor after the stripping operation. The machine includes a support frame, a drive plate driven by a motor about a vertical rotational axis, a reversible work plate mounted under the drive plate and carrying cutter blocks with cutter inserts at one face and abrasive-carrying devices at the opposite face. Therefore, after a floor stripping operation by the cutter inserts, the work plate can be reversed and a floor re-surfacing operation be carried out by using the abrasive-carrying devices. A change speed system enables to drive the work plate at a higher speed during floor re-surfacing than during floor stripping. Longitudinally adjustable weights are carried by the support frame to adjustably bias the work plate against the floor. A vacuum cleaner unit is carried by the support frame and includes an air inlet mouth formed by a shroud carried by the support frame with the mouth in the rotational plane of the work plate. The change speed system includes a driving and a driven pulley and a belt selectively trained in complementary grooves of the two pulleys, the grooves being of different diameters. If the motor is an internal combustion engine, a belt tightening lever is provided; normally it is biased in belt tightening position but can be released by an actuating lever mounted on the handle and accessible to the machine operator.