automobile enginering
TRANSCRIPT
-
8/12/2019 Automobile Enginering
1/9
-
8/12/2019 Automobile Enginering
2/9
Steering Ratio:-DEF:- It is the ratio of the angle turned by the steering wheel to the
corresponding turning angles of the stub axle.
For car and lighter vehiclesits value lies around 12:1
For heavy vehiclesits value is 35:1
Reversibility:-
DEF:-A steering gear is said to be reversible if by turning of stub axle, it
is possible to turn the steering wheel. This can be made irreversibility
by making the pitch angle of the screw used very less.
Irreversibility has both its advantages and disadvantages.
-
8/12/2019 Automobile Enginering
3/9
Advantage:-
The road shocks are not transmitted to the steering wheel and for that
reason the driver does not have to experience the kicks at the
steering wheel.
Disadvantage:-
Due to large amount of friction present in the irreversible system, theforward efficiency is also very low and consequently steering
operation become quite heavy.
But presently designs are almost semi-reversible.
-
8/12/2019 Automobile Enginering
4/9
Special Steering Columns:-
Special steering column have been employed in many car which
provide safety and ease of operation to the driver.
Various type which shall be discussed here are:
1. Energy absorbing steering column2. Tilt wheel steering column
3. Tilt and telescope steering column
4. Steering column with anti-theft lock.
-
8/12/2019 Automobile Enginering
5/9
1) Energy absorbing steering column:-
Energy absorbing or collapsing steering column provides safety bycollapsing during impact in a front-end crash.
Two type of collapsing steering column are used now a days:
Mesh type column
Ball type column
-
8/12/2019 Automobile Enginering
6/9
-
8/12/2019 Automobile Enginering
7/9
2) Tilt wheel steering column:-
This type of steering column allows the driver to tilt the steering wheelfor ease during entry or exit. Even while driving, the driver can
adjust it at convenient angle. This can be done easily by releasing
a lever on the side of the steering column and moving the wheel
into the desired position, where it locks itself in place.
-
8/12/2019 Automobile Enginering
8/9
3) Tilt and telescopic steering column:-
This type of steering has all the feature of the tilt wheel steeringexplained earlier in addition to the convenience of telescope
steering which adds to drivers comfort. The telescopic motion is
under the steering wheel. Both telescopic and tilting adjustment
can be made with no loss of steering control.
-
8/12/2019 Automobile Enginering
9/9
4) Steering column with anti-theft lock:-
This type o arrangement provides additional safety against theft. By
simply turning the ignition to the lock position and removing thekey, the ignition and steering wheel and on some models, the
gear shift lever of the transmission, are locked simultaneously.
When the ignition key is removed and the steering wheel is turned
to one extreme, the steering gets locked. When the ignition key is
inserted in its slot and turned, the lock is off.