Automobile steering gear, also known as steering gear and steering gear, is an important component in the steering system of an automobile. Its function is to increase the force transmitted by the steering wheel to the steering transmission mechanism and change the direction of force transmission.

Commonly used are rack and pinion type, worm crank pin type and circulating ball type.

1) Rack and pinion steering gear: It is a common steering gear. Its basic structure is a pair of intermeshing pinions and racks. When the steering shaft drives the pinion to rotate, the rack moves in a straight line. Sometimes, the steering wheel can be steered by directly driving the tie rod by the rack. So, this is a simple diverter. It has the advantages of simple structure, low cost, sensitive steering, small size, and can directly drive the tie rod. Widely used in automobiles.

2) Worm crank pin type steering gear: it is a steering gear with the worm as the driving part and the crank pin as the driven part. The worm has a trapezoidal thread, and the finger-shaped tapered pin is supported on the crank with a bearing, and the crank and the steering rocker shaft are integrated. When turning, the worm is rotated by the steering wheel, and the conical finger pin embedded in the worm screw groove rotates on its own and makes an arc movement around the steering rocker arm shaft, thereby driving the crank and the steering vertical arm to swing, and then through the steering transmission mechanism to make the steering Wheel deflection. This kind of steering gear is usually used on trucks with large steering force.

3) Recirculating ball steering gear: Recirculating ball power steering system. The main structure consists of two parts: the mechanical part and the hydraulic part. The mechanical part is composed of shell, side cover, upper cover, lower cover, circulating ball screw, rack nut, rotary valve spool, and fan gear shaft. Among them, there are two pairs of transmission pairs: one pair is screw, nut, and the other pair is rack, gear sector or sector gear shaft. A cyclic rolling steel ball is installed between the screw rod and the rack nut, so that the sliding friction becomes rolling friction, thereby improving the transmission efficiency. The advantage of this steering gear is that it is easy to operate, less wear and tear and has a long life. The disadvantage is that the structure is complex, the cost is high, and the steering sensitivity is not as good as the rack and pinion type.