SHRI J.J.T. UNIVERSITY, JHUNJHUNU

STEERING SYSTEM

SUBMITTED BY:- SUBMITTEDTO:-ANIL SHARMA Mr. RAKESH DUDDIROLL NO- ME13402 (ASSISTANT PROFESSOR)CLASS-B.TECH (ME)

DEPARTMENT OF MECHANICAL ENGINEERING

STEERING

Defination:-• The function of the steering system is to convert the rotary

movement of the steering wheel into angular turn of the front wheels.

REQUIREMENTS OF STEERING SYSTEM

For the smooth performance of the system, the steering system

of any vehicle should fulfill the following requirements:

It should multiply the turning effort applied on the steering

wheel by the driver.

It should be to a certain degree irreversible so that the shocks

of the road surface encountered by the wheels are not

transmitted to the driver’s hands.

FUNCTION OF STEERING SYSTEM

It helps in swinging the wheels to the left or right.

It helps in turning the vehicle at the will of the driver.

It provides directional stability. It helps in controlling wear and tear of tyres.

STEERING MECHANISMS

There are two types of steering gear mechanisms:

1. Davis steering gear

2. Ackermann steering gear

DAVIS STEERING GEAR

The Davis gear mechanism consists

of a cross link KL sliding parallel to

another link AB and is connected to

the sub axels of the front wheels by

means of two similar bell crank

levers ACK and DBK pivoted at A

and B respectively.

The cross link KL slides in the

bearing and carries pins at its end K

and L.

The slide blocks are pivoted on these pins and move with the turning of

bell crank levers as the steering wheel is operated . When the vehicle is

running straight ,the gear is said to be in its mid- position. The short arms

AK and BL are inclined an angle 90+alpha to their stub axles AC and BD

respectively.

ACKERMANN STEERING GEAR

The Ackermann steering gear

mechanism consists of a cross link KL

connected to the short axles AC and BD

of the front wheels through the short

arms AK and BL, forming bell crank

levers CAK and DBL respectively.

When the vehicle is running straight, the

cross link KL is parallel to AB, the short

arm AK and BL both make angle to the

horizontal axis of chassis.

CAMBER

The angle between the centre line of the

tyre and the vertical line when viewed

from the front of the vehicle is known as

camber. When the angle is outward, so that the

wheels are farther apart at the top then at the bottom, the camber is positive.

When the angle is inward, so that the wheels are closer together at the top then at the bottom, the camber is negative.

Any amount of camber, positive or negative, tends to case uneven tyre wear on one side then on the other side. Camber should not exceed 2degree.

TYPES OF CAMBER

ROLE OF CAMBER:- In early automobiles, the wheels were

given positive camber in order to improve durability of the

front axle, and to cause the tyres to contact the road surface

at right angles to prevent uneven tyre wear on roads where

the center of the road is higher than the edge.

ZERO CAMBER:- The main reason for adopting zero camber

is that it prevents uneven wear of tyres. If the wheels are

positive camber, the out side of the tyres turns on a shorter

radius then the inside of the tyre.

CASTER

In addition to being tilted inward toward the centre of the

vehicle, the king pin axis may also be tilted forward or

backward from the vertical line.

This tilt is known as caster. Thos, the angle between the

vertical line and the king pin center line in the plane of the

wheel is called the caster angle.

When the top of the king pin is backward, the caster angle is

positive, and when it is forward the caster angle is negative.

The caster angle is modern vehicles ranges from 2 to 8 degree

Thank You:-

WRITTRN BY-

ANIL SHARMA