Vehicle Construction Flashcards
What five parts comprise the chassis
Frame, engine, suspension system, steering, mechanical parts (with the body removed)
body over frame means
body bolted to thick steel framework
unibody construction means
body parts welded or adhesive bonded together to form a frame
front clip is…
front bumper to firewall.
rear clip is…
rear bumper to trunk
the cowl is…
the panel at the rear or the front section right in front of the windshield. covers gap between hood and windshield or trunk and windshield.
what does a rocker panel do
On unibody automobiles where the body and frame of the vehicle are one, rocker panels provide the structural reinforcement that keeps the bottom of the vehicle from sagging in the middle. They are normally welded to the floor pan and pillars, kickpanels or quarter panels.
what are cross members and what do they do?
A cross member is a structural component of a car, normally made of steel and bolted across the underside of the vehicle. As well as supporting the engine and transmission of the car and keeping body panels aligned, it aids the suspension system by maintaining stability.
what is a crush zone
areas in unibody that are intentionally made weaker to collapse during a collision and absorb some of the impact and redistribute around the passenger cabin.
what is a floor tunnel?
in front engine, rear wheel drive vehicles, the tunnel for the transmission and drive shaft.
longitudinal vs transverse engine placement?
perpendicular vs. parallel to axles.
what is torque steer?
engine torque is transmitted into the steering wheel under hard acceleration.
what is the area between the back glass and trunk lid called?
upper rear panel.
where are rocker to rail braces located?
between rocker panel and frame rail.
many small pickups have what types of frames?
bolt on removable stub frame under the engine.
what are unibody torque boxes
allow controlled twisting and crushing of structure during severe collisions. They also secure passenger compartment to frame rails.
front engine, front wheel drive vehicles combine what two parts and eliminate what one part?
combine transmission and differential into a transaxle, and eliminate drive shaft.
what type of engine and drive handles snow best and why? FF, FR, MR
front engine, front wheel drive, FF becaues there is more engine and transaxle weight over the drive wheels.
what does a differential do?
drive a pair of wheels while allowing them to rotate at different speeds
what does a transaxle do? what configuration is it common in?
universal when the engine and drive wheels are on the same side of the car.
operation of any transaxle is exactly the same as that of any transmission. The difference is this: Instead of being connected via a long driveshaft to the rear axle, the transmission drives a large gear that meshes directly with the differential’s ring gear. The differential itself (which would be mounted on the rear axle in a rwd car) is located in the transaxle housing, mounted parallel to the transmission. As power is applied, the differential distributes it to the two front wheels via half-shafts.
what is a composite unibody? AKA space frame?
made of special plastics and or carbon fiber adhesive bonded/structurally glued to each other. the use if lightweight plastics nd carbon fiber lowers total vehicle wehight for better performance and fuel economy
what 3 parts of a unibody keep passengers safe during a collision
crush zones, torque boxes and cross members.
what is one disadvantage of unitized vehicle design?
the damage is not localized to components, but spread
how does rack and pinion steering work?
round toothed gear from the steering wheel is attached to a toothed linear bar. the teeth pull the rack the direction you’d like to turn. Rack attached to tie rods, then to the steering control arms then to the hub.
benefits of unibody construction
more rigid due to the forces spreading over the entire vehicle. less material lighter better fuel economy handling acceleration deceleration.
what is designed to stiffen a unibody structure?
cross members and bracing
what is the purpose of a frame horn
Cast iron “horn” is a spring hanger as well as a connection for front bumper braces. These horns are securely riveted into the end of the frame. Usually the whole frame can bend before the cast iron horn breaks.
