Types Vehicle frame

1 types

1.1 ladder frame
1.2 unibody
1.3 backbone tube
1.4 x-frame
1.5 perimeter frame
1.6 platform frame
1.7 space frame
1.8 subframe

types
ladder frame

ladder chassis diagonal cross-bracing , lightening holes

so named resemblance ladder, ladder frame 1 of simplest , oldest of designs. consists of 2 symmetrical beams, rails, or channels running length of vehicle, , several transverse cross-members connecting them. seen on vehicles, ladder frame gradually phased out on cars in favor of perimeter frames , unitized body construction. seen on trucks. design offers beam resistance because of continuous rails front rear, poor resistance torsion or warping if simple, perpendicular cross-members used. also, vehicle s overall height greater due floor pan sitting above frame instead of inside it.

unibody

citroën traction avant body-chassis unit (1934)



1942 nash ambassador 600 cutaway drawing



saab 9000 safety cell in red , orange (2005)



backbone chassis of 1962 lotus elan

the term unibody or unit body short unitized body, or alternatively unitary construction design. engineering approach of vehicle describes of vehicle, one-piece frame , body structure a

type of body/frame construction in body of vehicle, floor plan , chassis form single structure. such design lighter , more rigid vehicle having separate body , frame.

traditional body-on-frame architectures has shifted lighter unitized body structure used on cars. last uk mass-produced car separate chassis triumph herald, discontinued in 1971.

integral frame , body construction requires more welding unstressed body conventional frame. in integrated body structure, entire car load-carrying unit handles loads experienced vehicle—forces driving cargo loads. integral-type bodies wheeled vehicles typically manufactured welding preformed metal panels , other components together, forming or casting whole sections 1 piece, or combination of these techniques. although referred monocoque structure, because car s outer skin , panels made load-bearing, there still ribs, bulkheads , box sections reinforce body, making description semi-monocoque more appropriate.

the first attempt develop such design technique on 1922 lancia lambda provide structural stiffness , lower body height torpedo car body. lambda though open layout, unstressed roof, made less monocoque shell , more bowl - 11,000 produced.

a key role in developing unitary body played american firm budd company, thyssenkrupp budd. budd supplied pressed-steel bodywork, fitted separate frames, automakers dodge, ford, buick, , french company, citroën.

in 1930, joseph ledwinka, engineer budd, designed automobile prototype full unitary construction.

citroën purchased unitary body design citroën traction avant. high volume, mass production car introduced in 1934 , sold 760,000 units on next 23 years of production. application first iteration of modern structural integration of body , chassis, using spot welded deep stamped steel sheets structural cage, including sills, pillars , roof beams. in addition unitary body no separate frame, vehicle featured other novelties such four-wheel independent suspension, , front-wheel drive. result of these innovations, traction avant had low-slung appearance futuristic era.

for chrysler airflow (1934–1937) budd supplied variation - 3 main sections airflow s body welded chrysler called bridge-truss construction. chrysler airflow unfortunately, method not ideal - panel fits poor. convince skeptical public of strength of unibody both citroën , chrysler created advertising films showing cars surviving after being pushed off cliff.

opel second european , first german car manufacturer produce car unibody structure - production of compact olympia started in 1935. larger kapitän went production in 1938, although front longitudinal beams stamped separately , attached main body.

the streamlined 1936 lincoln-zephyr conventional front-engine, rear-wheel-drive layout utilized unibody structure. 1941, unit construction no longer new idea cars, unheard of in [american] low-price field [and] nash wanted bigger share of market. single unit body construction of nash 600 provided weight savings , nash s chairman , ceo, george w. mason convinced unibody wave of future.

since more cars redesigned unibody structure, considered standard in industry . 1960, unitized body design used detroit s big 3 on compact cars (ford falcon, plymouth valiant, , chevrolet corvair). after nash merged hudson motors form american motors, rambler-badged automobiles continued exclusively building variations of unibody.

although 1934 chrysler airflow had weaker usual frame , body framework welded chassis provide stiffness, in 1960, chrysler moved body-on-frame construction unit-body design of cars.

most of american-manufactured unibody automobiles used torque boxes in vehicle design reduce vibrations , chassis flex, exception of chevy ii had bolt-on front apron (erroneously referred subframe). american motors (with partner renault) during late-1970s incorporated unibody construction when designing jeep cherokee (xj) platform using manufacturing principles (unisides, floorpan integrated frame rails , crumple zones, , roof panel) used in passenger cars, such hornets , all-wheel-drive eagles new type of frame called uniframe ... robust stamped steel frame welded strong unit-body structure, giving strength of conventional heavy frame weight advantages of unibody construction. design used xjc concept developed american motors prior absorption chrysler, later became jeep grand cherokee (zj). —including modern day sport utility vehicles (jeep grand cherokee et al.).

the unibody preferred construction mass market automobiles , crossovers. design provides weight savings, improved space utilisation, , ease of manufacture. acceptance grew dramatically in wake of 2 energy crises of 1970s , 2000s compact suvs using truck platform (primarily usa market) subjected cafe standards after 2005 (by late-2000s truck-based compact suvs phased out , replaced crossovers). additional advantage of strong-bodied car lies in improved crash protection passengers.

backbone tube

a backbone chassis type of automobile construction chassis similar body-on-frame design. instead of two-dimensional ladder type structure, consists of strong tubular backbone (usually rectangular in cross section) connects front , rear suspension attachment areas. body placed on structure.

x-frame

rolling x-frame chassis

this design used full-size american models of general motors in late 1950s , 1960s in rails alongside engine seemed cross in passenger compartment, each continuing opposite end of crossmember @ extreme rear of vehicle. chosen decrease overall height of vehicles regardless of increase in size of transmission , propeller shaft humps, since each row had cover frame rails well. several models had differential located not customary bar between axle , frame, ball joint atop differential connected socket in wishbone hinged onto crossmember of frame.

the x-frame claimed improve on previous designs, lacked side rails , did not provide adequate side-impact , collision protection. design replaced perimeter frames.

perimeter frame

anadol fw11 prototype perimeter frame

similar ladder frame, middle sections of frame rails sit outboard of front , rear rails behind rocker / sill panels. done allow lower floor pan, @ passenger footwells, lower passengers seating height , therefore reduce overall vehicle height in passenger cars. became prevalent design body-on-frame cars in united states, not in rest of world, until uni-body gained popularity. allowed annual model changes introduced in 1950s increase sales, without costly structural changes. of 2014, there no perimeter frame automobiles sold in united states after ford motor company phased out panther platform in 2011, ended perimeter frame passenger car in united states (the chevrolet corvette has used variation of perimeter frame since 1963, fourth generation variant current generation of 2016 has elements of perimeter frame integrated internal endoskeleton serves clamshell).

in addition lowered roof, perimeter frame allows lower seating positions when desirable, , offers better safety in event of side impact. however, design lacks stiffness, because transition areas front center , center rear reduce beam , torsional resistance, hence use of torque boxes, , soft suspension settings.

platform frame

this modification of perimeter frame, or of backbone frame, in passenger compartment floor, , luggage compartment floor have been integrated frame loadbearing parts, strength , rigidity. neither floor pieces sheet metal straight off roll, have been stamped ridges , hollows strength.

platform chassis used on several successful european cars. well-known of volkswagen beetle, on called body on pan construction. german example mercedes-benz ponton cars of 1950s , 1960s, called frame floor in english-language advertisements.

the french renault 4 of on 8 million made, used platform frame. frame of citroen 2cv represents more minimal interpretation of platform chassis.

space frame

in (tubular) spaceframe chassis, suspension, engine, , body panels attached three-dimensional skeletal frame of tubes, , body panels have little or no structural function. in order maximise rigidity , minimise weight, design makes maximum use of triangles, , forces in each strut either tensile or compressive, never bending, can kept thin possible.

jaguar c-type frame

the first true spaceframe chassis produced in 1930s buckminster fuller , william bushnell stout (the dymaxion , stout scarab) understood theory of true spaceframe either architecture or aircraft design.

the 1951 jaguar c-type racing sports car won le mans 24 hours twice, had lightweight multi-tubular, triangulated frame, on aerodynamic aluminium body crafted.

the italian term superleggera (meaning super-light ) trademarked carrozzeria touring lightweight sports-car body construction resembles space-frame chassis. using three-dimensional frame consists of cage of narrow tubes that, besides being under body, run fenders , on radiator, cowl, , roof, , under rear window, resembles geodesic structure. skin attached outside of frame , made of aluminium. body construction not stress-bearing, , still requires addition of chassis.

the lamborghini aventador has carbon fibre central monocoque, front , rear steel subframes, mounting mechanicals


subframe

a subframe distinct structural frame component, reinforce or complement particular section of vehicle s structure. typically attached unibody or monocoque, rigid subframe can handle high chassis forces , can transfer them evenly on wide area of relatively thin sheet metal of unitized body shell. subframes found @ front or rear end of cars, , used attach suspension vehicle. subframe may contain engine , transmission. of box steel construction, may tubular.

examples of passenger car use include 1967–1981 gm f platform, numerous years , models built on gm x platform (1962), gm s m/l platform vans(chevrolet astro/gmc safari, included all-wheel drive variant), , unibody amc pacer incorporated front subframe isolate passenger compartment engine, suspension, , steering loads.