In the past a number of reversing traverse mechanisms have been proposed and constructed. In a common friction type device, one or more roller elements were swivel-mounted on a base member which moved along a rotating shaft at a given speed, depending on the rate of shaft rotation and the angle at which the roller means was disposed with respect to the shaft. Frequently, several rollers were used to engage the shaft in order to minimize slippage and increase efficiency. In case where more than one roller was employed, they were usually connected by means of gears or linkages to enable all of them to be swiveled simultaneously in response to swiveling of any given one. A reversal in the direction of travel of the mechanism was effected by engagement of a swivel arm connected to one roller with a fixed abutment located at a predetermined point along the shaft. However, there were distinct disadvantages to this construction, in that as the swivel arm was turned, the relative angle between the rollers and the shaft slowly decreased which resulted in a slow-down of the traversing movement of the mechanism immediately before reversal. Under some circumstances there was a distinct possibility that as the rollers were swiveled they could, at some point during a reversal, assume a "dead" position wherein their axes of rotation would be parallel to the shaft axis. Under such a condition the traversing movement would cease and the rollers would have to be manually swiveled to initiate further traversing movement.