Backbone tube chassis is a type of 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. It was first used in the English Rover 8hp
of 1904 and then the French Simplicia
automobile in 1909.
The backbone chassis was extensively developed by Hans Ledwinka
who used it in greater numbers on the Tatra 11
and subsequent vehicles. Ledwinka later used backbone frame with central tube and axles with swinging driveshafts on Tatra
trucks, became known as ''Tatra-concept''.
The truck backbone chassis is a design feature of Czech Tatra heavy trucks
(cross-country, military etc.). Hans Ledwinka
used this style of chassis for the Tatra 11
car in 1923.
He then developed the design on trucks with 6x4 model Tatra 26
, which had excellent off-road abilities.
chassis with rear Chapman strut
This type of chassis has been used in numerous sports car
s. It does not provide protection against side collision
s, and thus has to be combined with a body that would compensate for this shortcoming.
Examples of cars using a backbone chassis are Simplicia
(1910), De Tomaso Mangusta
, DMC DeLorean
, Lloyd 600
, Lotus Elan
, Lotus Esprit
, Škoda Popular
, Škoda Rapid
, Škoda Superb
, Tatra 77
, Tatra 97
etc. and TVR S1
. Trucks with a backbone chassis include the Tatra 111
, Tatra 148
and Tatra 815
. Some cars also use a backbone as a part of the chassis to strengthen it. Examples include the Volkswagen Beetle
, where the transmission tunnel forms a backbone.
Hybrid backbone-ladder chassis
may appear to be using a backbone in addition to the outer space frame
. But examination shows that, in standard form, it is adding negligible stiffness and only serves as a convenient support structure for the sheet metal panels forming the transmission tunnel
. The Triumph Herald
and Triumph Vitesse
used a twin flanged box section backbone carrying the main torsional and bending loads, with light channel section side rails to stiffen the body, while the Triumph Spitfire
and Triumph GT6
sports cars used only the twin-box section backbone, with separate side members in the body, and rear suspension fore and aft loads were also taken by the floor, not the backbone chassis directly.
* A standard-conception truck's superstructure has to withstand the torsion twist, and subsequent wear reduces vehicle's lifespan.
* The half-axles have better contact with the ground when operated off-road. This has little importance on roads.
* The vulnerable parts of the drive shaft are covered by a thick tube. The whole system is extremely reliable. However, if a problem occurs, repairs are more complicated.
* The modular system enables configurations of 2-, 3-, 4-, 5-, 6-, or 8-axle vehicles with various wheel bases.
* Manufacturing the backbone chassis is more complicated and more costly. However, the more axles with all-wheel drive are needed, the cost benefit turns in favor of backbone chassis.
* The backbone chassis is heavier for a given torsional stiffness than a uni-body.
* The chassis gives no protection against side impacts.
* Tatra concept
* Frame (vehicle)
* Swing axle
* Comparison of standard ladder chassis and backbone chassis with half axles on off-road testing track with emphasis on the twist of superstructure (video):
(Renault fire engine)
(Tatra T815 fire engine)
Category:Automotive chassis types