The automobile industry is a fast developing industry.
From the later 18th century when the first automobile was put on road, this industry has developed tremendously. Now there are thousands of factories all over the world manufacturing numerous types of automobiles. This industry employs crores of men and women directly and indirectly in allied industries. The automobile engines are also being used in engine powered machines for agriculture, constriction and manufacturing processes. Various types of small engines are also being used in lawn movers,power saws, snow removers and similar equipment. The automobile industry is a developing and demanding industry which does not find its end or saturation point. There is a great demand for varied types of automotive products, vehicles and engines. There is also a great demand for trained and experienced persons in this industry for diagnosing motor vehicle troubles, repairing and replacing engines components, transmissions, propeller shafts, differentials, axles, steering system components, brake system components, suspension components, air conditioners, heaters, body and glass work.
There are numerous types of automobiles used in the world. There are in general three main classifications of the various types of vehicles.
(1) The single-unit vehicles or load carriers.
(2) Articulated vehicles.
(3) The heavy tractor vehicles.
Single-unit vehicles are of conventional four –wheel type. The great majority of vehicles are of two axle design. In these vehicles the front axle is a steering non-driving axle and the rear axle is the driving axle. With the passage of time, a great many changes have taken place in the number of axles and the driving arrangements.
In this classification, digital terms like 4×2, 4×4, 6×4 etc. are commonly ysed. The first figure denotes the total number of wheels and the second figure the number of driving wheels.
A lower powered three-wheeler with a single steering wheel in front and a conventional rear driving axle is an example of articulated vehicles. It has a greater handling ability in awkward places. It can be turned about its own tail due to the three-wheel construction. The coupling mechanism between semi-tailer and tractor in most of these vehicles is arranged for automatic connection and coupling up necessitation only its reversing into the position. But for uncoupling operation, a lever is provided within the driver’s cabin to reverse the whole process. A pair of retractable wheels in front are also provided. Along with the coupling or uncoupling operation, they can be raised or lowered automatically.
To move heavy loads, heavy tractor or independent tractor vehicles commonly operate in pair either in tandem or as ‘puller’and ‘pusher’.
A special consideration is made in respect of the drive to the front wheels in all-wheel-drive vehicles. We know that the front wheels are to travel farther than the reer wheels on every band. The wind-up produced by this difference of travel over-stresses the transmission system. To avoid this great necessity of some form of differential or its equivalent has been felt to provide it the front and rear drives. It has been seen that if the conditions are not very abnormal, sufficient amount of tyre slip taking place under running conditions would release these stresses completely.
An all-wheel drive is better than the introduction of differentials between the various axles. It provides adhesion under the worst possible conditions. On the other hand, the drive to all the other axles is liable to be lost if any one axle or group of axles loses adhesion.
Types of automobiles. There are numerous types of automobile found in different parts of the world. With respect to different purposes, the various types of automobiles are classified as under:
1. With respect to the use:
(a) Auto-cycles and moppets. (b) Scooters and Motor cycles. (c) Cars, Station Wagons and Pick-ups. (d) Lorries (Buses) and Trucks. (e) Tractors.
2. With respect to the use:
(a) Heavy Transport Vehicles or Heavy Motor Vehicles: Tata, Leyland.
(b) Light Transport Vehicles, or Light Motor Vehicles (Cars, Jeeps, Scooter/Motor Cycles).
(c) Medium Vehicles: Tempo, Minibus, Station Wagon
3. With respect to the fuel used:
(a) Petrol Vehicles: Cars, Scooters, Motor Cycles. (b) Diesel Vehicles: Coal-gas, Gas Turbine or Producer-Vehicles.(d) Electric Vehicles-using electric storage batteries or accumulators to drive electric motors attached to the front or rear wheels, e.g. Heavy cranes.(e) Steam Vehicles-It is now obsolete.
4 With respect to the make;
(a) Leyland, Tata. (b) Ambassador, Fiat (Primer-President), Standard, Herald etc. (c) Vespa/Bajaj, Raj, Hans, Rajdoot, Royal Enfield, Vijay Delux, Vijay Kesari, Priya.
5 With respect to wheels and axles:
(a) Two Wheelers: Motor Cycles/Scooters. (b) Three wheelers: Tempos, Auto Rickshaws.(c) Four Wheelers; Cars, Jeeps, Buses ,Trucks(6 Tyres) etc. Buses and Trucks have six tyres out of which four are carried on the rear wheels for additional traction. (d) Axle 6 wheelers (10 tyres) Vehicles: Shaktiman, Dodge.
6 With respect to the drive:
(a) Left hand drive-most of the American vehicles.
(b) Right hand drive-most of the Indian vehicles.
(c) Fluid drive-Vehicles using Fluid Coupling Engine and Transmission.
(d) Front wheel drive- volks Wago, Skoda, Austin.
(e) Rear wheel drive- most of the Indian vehicles.
(f) All wheel drive-Jeep 4×4.
7.With respect to motion: (a) Reciprocating-piston Engines. (b) Rotary-wankel Engine, Vas Turbine.
8. With respect to the suspension ;(a) Conventional- Leaf Spring. (b) Independent-Coil, Torsion bar, Pneumatic.
9. With respect to the body and number of doorsLa) Sedan-Two doors, four doors.(b) Convertible-jeep. (c) Station Wagon. (d) Delivery Van.
10. With respect to transmission:
(a) Conventional-Most of Indian vehicles.
(b) Semi-automatic-Modern British vehicles.
(c). Automatic-American Vehicles.