RECIRCULATING-BALL-AND-NUT STEERING

A very popular type of steering gear . It uses a series of ball bearings that feed through and around and back through the grooves in the worm gear and nut on the steering shaft . The turning forces are transmitted through these ball bearing to a sector gear on the pitman-arm shaft. When the steering wheel is turned, the worm gear on the end of the steering shaft rotates and the movement of the recirculating balls causes the ball nut to move up and down along the worm. Movement of the ball nut is carried by teeth to the sector gear which in turn moves with the ball nut to rotate the pitman-arm shaft and activate the steering linkage . The balls recirculate from one end of the ball nut to the other through a pair of ball return guides. This system is also called ball-and-nut steering or worm-and-recirculating-ball steering.