Abstract: A belt clutch control apparatus is disclosed having a control handle and linkage means for selectively controlling the transmission and power from a driving pulley to a driven pulley through a driving belt. In a preferred embodiment, the apparatus is specially adapted to control the operation of the cutting blades on a riding mower. The linkage includes an undercenter connecting link for transmitting rotational movement of the control shaft to a bellcrank, which engages a tension spring to operatively move an idler pulley between engaged and disengaged positions relative to the driving belt. The undercenter link moves exclusively between first and second undercenter positions, and is never forced into an overcenter position. An assist spring is provided for securing the undercenter link in both its on and off undercenter positions, thereby relieving the idler pulley spring for this purpose.

Abstract: A four wheel steering system for a vehicle which significantly reduces or eliminates scrubbing of the outside tires. A preferred embodiment is specially adapted for use on riding lawn mowers, and includes a longitudinally moveable cam plate having a pair of cam slots formed therein, each slot engaging an individual steering arm for separately steering each rear wheel. The cam plate is coupled to a sector gear which reciprocates in response to left and right hand movement of a steering wheel, with the sector gear interconnecting the front and rear wheel steering mechanisms. The slots in the cam plate are specially configured to vary the turning angles of the rear wheels so that the wheels turn through varying angles, thereby reducing scrubbing to an acceptable level. In a preferred embodiment, all four wheels may be calibrated to turn about a single point, thereby completely eliminating scrubbing.