A chassis (, ; plural ''chassis'' from French châssis ) is the load
of an artificial object, which structurally supports the object in its construction and function. An example of a chassis is a vehicle frame
, the underpart of a motor vehicle
, on which the body is mounted; if the running gear
such as wheels and transmission, and sometimes even the driver's seat, are included, then the assembly is described as a rolling chassis
Examples of use
In the case of vehicles, the term ''rolling chassis'' means the frame
plus the "running gear" like engine
, drive shaft
. An underbody (sometimes referred to as "coachwork
"), which is usually not necessary for integrity of the structure, is built on the chassis to complete the vehicle.
For commercial vehicle
s, a rolling chassis consists of an assembly of all the essential parts of a truck without the body to be ready for operation on the road. A car chassis will be different from one for commercial vehicles because of the heavier loads and constant work use. Commercial vehicle manufacturers sell "chassis only", "cowl and chassis", as well as "chassis cab
" versions that can be outfitted with specialized bodies. These include motor homes
, fire engines
s, box truck
In particular applications, such as school bus
es, a government agency like National Highway Traffic Safety Administration
(NHTSA) in the U.S. defines the design standards of chassis and body conversions.
An armoured fighting vehicle
's hull serves as the chassis and comprises the bottom part of the AFV that includes the tracks
, engine, driver's seat, and crew compartment. This describes the lower hull, although common usage might include the upper hull to mean the AFV without the turret
. The hull serves as a basis for platforms on tank
s, armoured personnel carrier
s, combat engineering vehicle
In an electronic device
(such as a computer
), the chassis consists of a frame or other internal supporting structure on which the circuit board
s and other electronics are mounted.
In some designs, such as older ENIAC
sets, the chassis is mounted inside a heavy, rigid cabinet, while in other designs such as modern computer case
s, lightweight covers or panels are attached to the chassis.
The combination of chassis and outer covering is sometimes called an ''enclosure''.
In firearms, the chassis is a bedding
frame on long gun
s such as rifle
s to replace the traditionally wooden stock
, for the purpose of better accurizing
the gun. The chassis is usually made from hard metallic material such as aluminium alloy
(and less frequently stainless steel
or titanium alloy
) due to metals having superior stiffness
and compressive strength
compared with wood or synthetic polymer, which are commonly used in conventional rifle stocks.
The chassis essentially functions as a more extensive pillar bedding, providing a metal-on-metal bearing surface
that has reduced shifting potential under the stress of recoil
. A barrel
bedded into a metal chassis would theoretically operate more consistently during repeated firing, resulting in better precision
. With the increasing availability of CNC machining
, chassis have become more affordable and sophisticated, and gained increasing popularity as it can also be expanded to accommodate customizable "furnitures" (buttstock
, pistol grip
, etc.) and rail interface system
s that provide mounting points for various accessories.
, construction from a structural shell instead of a structural frame
*Starry, Donn A. GEN. ''Mounted Combat in Vietnam.'' ''Vietnam Studies''; Department of the Army
, Washington, D.C.
Category:Automotive chassis types
Category:Carriages and mountings