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SteeringSystem

The direction of the automobile under way is changedby turning the front wheels with the aid of the steering system. The steeringsystem includes a steering gear and a steering control linkage. The rotation ofthe steering wheel is imparted to the levers and rods of the linkage by whichthe steerable wheels are turned.

The steering column with the steering wheel isinstalled in the driver’s cab . Its upper part is secured to the instrumentboard by a clamp ,and the lower end is attached through bushings to thesteering gear housing .

The steering gear increases the force transmittedfrom the steering wheel to the pitman arm thus facilitating the turning of thesteerable wheels. Some automobiles are equipped with a hydraulic power steeringsystem intended to decreases the efforts spent by the driver to turn the wheelsand to damp the road jolts transmitted to the steering wheel .The booster isintegrated with the steering gear .

The steering gear includes a housing , a worm, aball nut, a rack made integral with the piston, a hydraulic booster, and atoothed sector integrated with the pitman arm shaft. The power steering systemof trucks is provided with an oil cooler.

The ball nut of the steering gear is rigidly securedinside the rack-piston. The thickness of the teeth on the rack and sector teethcan be adjusted by the adjusting screw driven in the side cover of the housing. To decrease friction between the worm and the nut .balls recirculate in theirthread .The rack-piston has resilient split rings of cast iron ensuring itstight fit in the steering gear housing.

The rotation of the steering shaft is converted intoprogressive motion of the rack-piston owing to displacement of the nut alongthe worm. The rack-piston teeth turn the sector, hence the shaft with thepitman arm.

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