Tuesday, February 2, 2016

Automobile Chassis And Frame


CHASSIS  

4 Wheel Chassis

6 Wheel Chassis
Automotive chassis is a skeletal frame on which various mechanical parts like engine, tires, axle assemblies, brakes, steering etc. are bolted. The chassis is considered to be the most significant component of an automobile. It is the most crucial element that gives strength and stability to the vehicle under different conditions. Automobile frames provide strength and flexibility to the automobile. The backbone of any automobile, it is the supporting frame to which the body of an engine, axle assemblies are affixed. Tie bars, that are essential parts of automotive frames, are fasteners that bind different auto parts together.

 Automotive chassis is considered to be one of the significant structures of an automobile. It is usually made of a steel frame, which holds the body and motor of an automotive vehicle. More precisely, automotive chassis or automobile chassis is a skeletal frame on which various mechanical parts like engine, tires, axle assemblies, brakes, steering etc are bolted. At the time of manufacturing, the body of a vehicle is flexibly molded according to the structure of chassis. Automobile chassis is usually made of light sheet metal or composite plastics. It provides strength needed for supporting vehicular components and payload placed upon it. Automotive chassis or automobile chassis helps keep an automobile rigid, stiff and unbending. Auto chassis ensures low levels of noise, vibrations and harshness throughout the automobile. The different types of automobile chassis include:

Ladder Chassis: Ladder chassis is considered to be one of the oldest forms of automotive chassis or automobile chassis that is still used by most of the SUVs till today. As its name connotes, ladder chassis resembles a shape of a ladder having two longitudinal rails inter linked by several lateral and cross braces.

Backbone Chassis: Backbone chassis has a rectangular tube like backbone, usually made up of glass fibre that is used for joining front and rear axle together. This type of automotive chassis or automobile chassis is strong and powerful enough to provide support smaller sports car. Backbone chassis is easy to make and cost effective.

Monocoque Chassis: Monocoque Chassis is a one-piece structure that prescribes the overall shape of a vehicle. This type of automotive chassis is manufactured by welding floor pan and other pieces together. Since monocoque chassis is cost effective and suitable for robotised production, most of the vehicles today make use of steel plated monocoque chassis.


Motorcycle Chassis
An important type of automotive chassis, motorcycle chassis comprise of different auto parts and components like auto frame, wheels, two wheeler brakes and suspension. Its basically the frame for motorbikes that holds these components together. A motorbike chassis can be manufactured from different materials. But the commonly used materials are steel, aluminum, or magnesium.

Car Chassis
The main structure of a car is known as chassis. Car chassis functions as a support for the different car parts. Automotive parts like engine, suspension & steering mechanism braking system, auto wheels, axle assemblies and transmission are mounted on the car chassis. 
Integral Chassis

Tata Nano Chassis

Bus Chassis

Bus chassis is the design and quality of bus chassis depends on the capacity of bus. It can be tailor made according to the needs and can be availed with features like transverse mounted engine, air suspension as well as anti-roll bars. A well manufactured bus chassis offers various benefits like high torque from low revs, superior brake performance and more. Bus chassis designed for urban routes differs from the one manufactured for suburban routes.
Volvo Bus chassis







                                      Truck Chassis
Truck chassis, the backbone of any truck is designed to provide a comfortable and dependable ride. New invention in automotive sector has influenced the automobile chassis manufacturers to adopt latest trends and come up with new designs. In the present world, a truck chassis comes with enhanced geometry, power steering, disc brakes and other truck parts.

FRAME
A frame is the main structure of the chassis of a motor vehicle. All other components fasten to it; a term for this is design is body-on-frame construction.
In 1920, every motor vehicle other than a few cars based on motorcycles had a frame. Since then, nearly all cars have shifted to unit-body construction, while nearly all trucks and buses still use frames.

TYPES OF FRAME
         
Ladder Frame
So named for its resemblance to a ladder, the ladder frame is the simplest and oldest of all designs. It consists merely of two symmetrical rails, or beams, and crossmember connecting them. Originally seen on almost all vehicles, the ladder frame was gradually phased out on cars around the 1940s in favor of perimeter frames and is now seen mainly on trucks.
This design offers good beam resistance because of its continuous rails from front to rear, but poor resistance to torsion or warping if simple, perpendicular crossmembers are used. Also, the vehicle's overall height will be higher due to the floor pan sitting above the frame instead of inside it.

 Backbone tube
Backbone chassis is a type of an automobile construction chassis that is similar to the body-on-frame design. Instead of a two-dimensional ladder type structure, it consists of a strong tubular backbone (usually rectangular in cross section) that connects the front and rear suspension attachment areas. A body is then placed on this structure.

Perimeter Frame
Similar to a ladder frame, but the middle sections of the frame rails sit outboard of the front and rear rails just behind the rocker panels/sill panels. This was done to allow for a lower floor pan, and therefore lower overall vehicle in passenger cars. This was the prevalent design for cars in the United States, but not in the rest of the world, until the uni-body gained popularity and is still used on US full frame cars. It allowed for annual model changes introduced in the 1950s to increase sales, but without costly structural changes.
In addition to a lowered roof, the perimeter frame allows for more comfortable lower seating positions and offers better safety in the event of a side impact. However, the reason this design isn't used on all vehicles is that it lacks stiffness, because the transition areas from front to center and center to rear reduce beam and torsional resistance, hence the use of torque boxes, and soft suspension settings.

Superleggera
 An Italian term (meaning "super-light") for sports-car construction using a three-dimensional frame that consists of a cage of narrow tubes that, besides being under the body, run up the fenders and over the radiator, cowl, and roof, and under the rear window; it resembles a geodesic structure. The body, which is not stress-bearing, is attached to the outside of the frame and is often made of aluminium.
  
Unibody
By far the most common design in use today, sometimes referred to as a sort of frame.
But the distinction still serves a purpose: if a unibody is damaged in an accident, getting bent or warped, in effect its frame is too, and the vehicle undrivable. If the body of a body-on-frame vehicle is similarly damaged, it might be torn in places from the frame, which may still be straight, in which case the vehicle is simpler and cheaper to repair.

Sub frame
The sub frame, or stub frame, is a boxed frame section that attaches to a unibody. Seen primarily on the front end of cars, it's also sometimes used in the rear. Both the front and rear are used to attach the suspension  to the vehicle and either may contain the engine and  transmission .
The most prolific example is the 1967-1981 Chevrolet Camaro.