frame - Abdullah Demir

Transcription

frame - Abdullah Demir
MARMARA ÜNİVERSİTESİ
TEKNOLOJİ FAKÜLTESİ
TAŞIT TEKNOLOJİSİ
ŞASİ, ÇERÇEVE ve
GÖVDE - KAROSER/İ
-GİRİŞVehicle Structure
Frame, Body, and Chassis
Abdullah DEMİR, Yrd. Doç. Dr.
Kısa Ufuk Turu
It should be noted that every automobile is a highly complex machine
which consists of 25 to 30 systems, about 500 modules, and more than
50,000 individual parts.
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
https://sellyourcarnow.wordpress.com/tag/second-hand-car-parts-brisbane/
It can take up to seven years to develop a new vehicle from an initial
concept to full series production. Most vehicles remain in series
production for approximately seven years. After initial production,
passenger vehicles are expected to remain in service for at least ten years
and should maintain a high resale value throughout their service life.
Engineers and designers must therefore consider a time frame of
approximately 25 years starting from the beginning of the concept phase.
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
Today, automakers only manufacture about 30 % of each car themselves. The
remaining 70 % of the components are purchased from suppliers.
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
http://www.tlc-mag.com/archive_issues/car_care_aug10_enlarge.html
Vehicle Function Levels
The V model can be applied to different levels of vehicle development. To
facilitate this, the vehicle is divided into different systems,
subsystems, modules, etc., until the most basic component level is
reached
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
Superimposed trends: trends based on the extrapolation of the past,
present trends, and future trends
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
Şasi, Çerçeve ve Gövde Karoser/i
The vehicle’s main components and sub - systems can be categorically
listed as: Power-train, chassis, exterior and interior trims, and the
body in white (BiW) or vehicle body - shell.
Body in white: Beyaz gövde. Bir otomobilin motor vb gibi ana parçaları ile trim
donanımı öncesi ana yapısıdır.
2004 5 series
http://www.forocoches.com/foro/showthread.php?t=3781364
2013-SL-Class_body_in_white
http://www.forocoches.com/foro/showthread.php?t=3781364
Body in White
www.experi-metal.com
indianautosblog.com - Mercedes Benz C-Class
Bütün taşıtlar kendilerini ve üzerlerindeki yükü taşıyan bir gövdeye
sahiptir. Kullanım amaçlarına göre farklı olmakla birlikte taşıtların
gövdeleri genel olarak iki ana kısımdan oluşur.
1. Şasi
2. Karoseri
A typical BiW consists of about 300 – 400 stamped pieces, however, only a few main
panels affect the overall geometry, fit and finish. These panels are the roof, the trunk
(inner, outer, and pan), the hood (inner and outer), the under - body, the wheel house, the body - side, A and B pillars, the floor pan, the front module (engine
cradle, crush zones, shock towers), the quarter panels, and doors (inner, outer).
A-pillar: A-direği / sütunu, Adikmesi.
Quarter panel: Arka kelebek
panel, çamurluk panel
Stamped pieces:
Preslenmiş parçalar
Figure : The different panels of the vehicle structure
Mohammed A. Omar, The Automotive Body Manufacturing Systems and Processes, © 2011 John Wiley & Sons Ltd. ISBN: 978-0-470-97633-3
Chassis
•
•
Consists of the vehicle’s frame and everything attached to it
except the body
Includes the tires, wheels, engine, transmission, drive axle
assembly, and frame Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Chassis Frames
The chassis frame is the commercial vehicle's actual load-bearing
element. It is designed as a ladder-type frame, consisting of side and
cross members. The choice of profiles decides the level of torsional
stiffness. Torsionally flexible frames are preferred in medium-and
heavy-duty trucks because they enable the suspension to comply better
with uneven terrain. Torsionally stiff frames are more suitable for
smaller delivery vehicles and vans. / Reff: Automotive Handbook
•
•
•
Chasis is a French term which denotes the whole
vehicle except body in case of heavy vehicles.
In case of light vehicles of mono construction it denotes
the whole body except additional fitting in the body.
Chassis consists of engine, brakes, steering system &
wheel mounted on the frame, differential, suspension.
Its Principal Function
•
•
•
•
•
To safety carry the maximum load.
Holding all components together while driving.
Accommodate twisting on even road surface.
Endure shock loading.
It must absorb engine - driveline torque.
"Introduction To Automobile" Sunumu, Saeindia.
FRAME
•
•
Frame is the main part of chassis on
which remaining part of chassis are
mounted.
Frame should be extremely rigid and
strong so that it can withstand
shocks,
twist,
stresses
and
vibrations when vehicle is moving on
road.
unibody (or monocoque)
 Strong metal structure that provides a
mounting place for other parts of the
vehicle
 Body-over-frame construction
 chassis parts and body bolt to the
frame
 Unibody (unitized) construction
 sheet metal body panels are welded
together to form the body and frame
"Introduction To Automobile" Sunumu, Saeindia.
Şasinin görevi: İnsan vücudundaki iskelet
gibi ana taşıyıcılık görevini yerine getirir.
Taşıtın birçok elemanını üzerinde taşır.
Kaynak: “Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
www.penncvs.com
Merdiven Tipi Şasi (Paralel Kollu Şasi): Kamyon ve otobüslerde
yaygın olarak kullanılan şasi tipidir. Paralel iki kol ve bu iki kola
bağlanmış kuşaklardan/traverslerden oluşur. Kollar genelde U,
kare, dikdörtgen ve daire kesitli olarak preste yapılırlar.
Kuşaklar ve üst yapı, kaynak, perçin ve cıvata ile şasi kollarına
Kaynak: “Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
bağlanır.
Ağır kamyonlar ve yük
taşıyan taşıtlar şasilidir ve
üzerinde sürücü kabini ile
yükleme
yapılan
kasası
vardır.
Kaynak: “Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
• The ladder frame is the
simplest and oldest of all
designs.
• It consists merely
symmetrical rails, or
of
two
• This design offers good beam
resistance because of its
continuous rails from front
to rear
• poor resistance to torsion
"Introduction To Automobile" Sunumu, Saeindia.
Kaynak: VW, Otomobil Teknolojisinin Temelleri
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
The Rolling/Driving Chassis
Vehicles with ladder-frame chassis configurations (mostly light trucks for the
US market) are often preassembled as a rolling chassis including the fuel
system, driveline, and other running gear (Figure). This rolling chassis
can be assembled by a system supplier and rolled or otherwise transported to
the OEM’s final assembly line.
Rolling chassis (DANA Corp.)
Bernd Heißing | Metin Ersoy (Eds.), Chassis Handbook Fundamentals, Driving Dynamics, Components, Mechatronics, Perspectives, 2011.
Çapraz Kollu (X Tipi) Şasi: Oldukça hafif bir yapısı
vardır. Daha çok kamyonetlerde tercih edilir.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Tek Kollu (Platform) Şasi: Ortada tek bir kol ve buna
bağlanmış kuşaklar, bazen de taban sacı ile bir bütün olarak
yapılırlar. Otomobillerde tercih edilir.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Çatal Kollu Şasi: Taşıt motorunun bağlanmasına ve
destek oluşturmasına elverişli bir şasi tipidir.
Kamyonetlerde ve otomobillerde tercih edilir.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Karma Tip Karoseri
Şasi ve karoserinin bir nevi kombinasyonundan meydana gelmiştir.
Taşıt, bir platform şasi veya çatal şasi ile gövde saçının kaynakla veya
cıvata ile birleştirilmesinden oluşur. Otomobil ve otobüslerde
uygulaması vardır.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Tam Taşıyıcı Karoseri
Günümüzde binek otomobiller şasisiz olarak imal edilmektedirler. Gövde
kendi kendini taşıyan bir formda dizayn edilmektedir. Genellikle karoseri
hücre tip dediğimiz gövdedir. Bilgisayarlar yardımı ile orijinal yapının ve
istenilen bölge veya parçaların tek tek deformasyon ve gerilmeleri
hesaplanabilir.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Hücre Tipi Karoseri
Taşıt gövdesi ayrı hücrelerden oluşur. Yolcu bölümü taşıtın ön ve
arkasına göre korunmaya alınmıştır. Çarpışma anında ön ve arka hücreler
daha elastik yapıldıkları için yolculara gelecek darbe minimuma
indirilmiştir. Binek otomobillerde genellikle uygulanan bir gövde tipidir.
“Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
Şasisiz Otobüs Gövdeleri
Otobüs imalinde şasisiz gövdeye örnek olarak gösterilen iki ana grup
vardır. Bunlar:
1. Platform takviyeli otobüs gövdesi
2. Tam taşıyıcı otobüs gövdesi (Kendini Taşıyıcı Yapı Biçimi)
Her iki yapı tipide şasili tipe nazaran hafiftir. Taşıt ağırlığında azalma tam
taşıyıcı otobüs gövdesinde daha fazladır. Şasinin çıkarılması ile araçta
yaklaşık %8 ağırlık azaltılmış olur. Ancak bunun bir kısmı mukavemet
arttırmak amacı ile tekrar kullanılır. Taşıtın boş ağırlığı ne kadar az ise
işletme şartları da o oranda ekonomik olur. Bu nedenle taşıtın ağır olması
istenmez.
www.haberortak.com
OKUMA PARÇASI
Şasi ve karoseri, otomobilin gövdesini oluşturur. Şasi çerçevesi (Şasi
çatkısı), aracın bütün parçalarını üzerinde taşıyan, motora, karoseriye
ve güç aktarma organlarına desteklik eden bir temeldir. Karoseri ise
aracın kaporta ya da gövde diye tabir edilen sac aksamıdır.
Günümüz araçlarında en genel anlamda iki tür şasi çerçevesi
bulunmaktadır. Bunlar ayrı şasi çerçevesi ve birleşik şasi
çerçevesidir.
Eğer şasi çerçevesi sonradan karoseriye bağlama yöntemleriyle
tutturulacak şekilde yapılmışsa ayrı şasi çerçevesi olarak
isimlendirilir. Şasi çerçevesi oldukça katı ve sağlam bir yapıya sahip
olmalıdır. Günümüz otomobillerinde pek kullanılmamaktadır. Daha
çok ağır ticari araçlarda kullanılır.
Birleşik şasi çerçevesinde ise; şasi çatkısında parçalar birleştirme
yöntemleri kullanılarak tutturulmuştur. Bazı birleştirme yerlerinde
kuvvetlendirmeler yapılmak zorundadır. Onun için birleşik karoserişasilerin çeşitli bölümlerinde birbirini kuvvetlendiren, tüm gövdeyi
birlikte destekleyen bir yapı özeliği vardır.
Gövde Tipleri
Body Types
Karoserinin görevi: Taşıta
şekil veren, fonksiyonları
yerine getirmesi için ana
hacim sağlayan kısmıdır.
Kaynak: “Şase ve Karoseri” Sunumu, TÜVTURK, 08/03/2006.
 Made
of
steel,
aluminum,
fiberglass, plastic, or composite
materials
 Forms the outside of the vehicle
 Serves as an attractive covering for
the chassis
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
The purpose of body design is to achieve the following:
• Aesthetics: to provide a pleasing overall appearance, surface quality and
consistent details.
• Structural function: to support the weight of the transported passengers
and load as well as the mechanical parts required for vehicle propulsion,
control and other system functions, so withstanding mechanical stresses
from multiple sources.
• Ergonomy and roominess: to supply easy access and adequate room for
the driver, passengers and transported goods.
• Safety: to ensure integrity of passenger compartment in the event of a
crash, while absorbing the impact energy as well as to reduce injuries to
vulnerable road users (pedestrians, wheelers), in case of collision.
• Aerodynamics: to minimize drag due to air impact; to control air flow
effects on tyre-road contact and vehicle stability.
• Insulation: to minimize noise, vibration and thermal transmission,
generated by body walls, by lack of sealing between compartment and
movable parts and by thermal radiation from the surfaces of passengers
compartment.
• Visibility: to provide the highest possible day and night visibility on the
environment and to host the lighting devices in the most effective way.
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
Moreover, the body must satisfy a series of
prerequisites:
• high reliability (to maintain design functions
vehicle life along),
• low cost (to minimize production investment,
process and material cost),
• high
material
recyclability
(by
rapid
disassembling and straightforward division of
heterogeneous materials).
These functions ere required by the completely
assembled body and are achieved through the
individual contribution of body components and
several body systems.
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
The interior and exterior
trims compose the front and
rear ends, the door system,
and the cockpit trim.
Finally, the body in white is
made up of the closures
(doors, hood, tail-gate) and
the frame, see Figure 1 ).
Hatırlatma: "Body in white" nedir?
Beyaz gövde. Bir otomobilin motor vb. gibi ana parçaları ile trim donanımı
öncesi ana yapısını ifade eder.
Mohammed A. Omar, The Automotive Body Manufacturing Systems and Processes, © 2011 John Wiley & Sons Ltd. ISBN: 978-0-470-97633-3
Body Types
Automobiles are available in several body types, including:
• sedan
• hardtop
• convertible
• hatchback
• station wagon
• minivan
• sport-utility vehicle
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Automobile Body Parts
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
emmesei.com
Toyota
Sedan
A sedan is a car with a four-door body configuration and a
conventional trunk or a sloping back with a hinged rear cargo hatch
that opens upward.
Sedan is the most
common body style that
are cars with four or
more seats and a fixed
roof that is full-height up
to the rear window.
Sedans can have two or
four doors.
Uses center body pillars, or “B” pillars, between the front
and rear doors. A hardtop does not use “B” pillars.
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Convertible
A convertible is
a car with a
removable
or
retractable top.
Uses a vinyl or cloth top that can be raised and
lowered
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Hardtop
A Volvo C70 with retractable hardtop
https://en.wikipedia.org/wiki/Hardtop
A hardtop is a rigid form
of automobile roof. They
may be detachable for
separate
storing,
retractable within the
vehicle
itself,
or
permanently attached to
an auto lacking a center
side-support known as a
B-pillar. The term is also
used to describe such
vehicles, principally the
last.
Hardtops may be either
two-door or four-door, and
tend to be more expensive
and collectible than sedan
models of the same
vehicle.
Hatchback
The large rear door allows easy access when hauling
items
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Station Wagon
Provides a large rear interior compartment
A wagon is a
car with an
extended body
and a roofline
that
extends
past the rear
doors.
Station wagon
or wagon is a
car with a fullheight body all
the way to the
rear; the loadcarrying space
created
is
accessed via a
rear door or
doors.
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Minivan
A minivan/van is a vehicle
with a box-shaped body
enclosing a large cargo or
passenger
area.
The
identified gross weight of a
van is less than 10.000 lb
≈ 4,500 kg. Vans can be
identifiable
by
their
enclosed
cargo
or
passenger area, short
hood, and box shape. Vans
can be divided into mini
van, small van, midsize
van, full-size van, and large
van. The van subdivision
Has a higher roofline for more headroom and cargo space has the same specifications
as SUV subdivisions.
Minivans are boxy wagon cars usually containing three rows of seats, with a capacity of six
or more passengers and extra luggage space.
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Sport-Utility Vehicle
An SUV (sport utility
vehicle) is a vehicle
with off-road capability.
SUV is designed for
carrying ten or fewer
persons, and generally
considered a multipurpose vehicle. Most
SUVs are four-wheeldrive with and increased
ground clearance. The
SUV is also known as 4by-4, 4WD, 4 × 4 or 4x4.
SUVs can be divided into
mini, small, midsize, fullProvides the comfort of a passenger car, the interior space of a size, and large SUV.
station wagon, and the durability of a truck
An MPV (multi-purpose vehicle) is designed as large cars or small buses having offroad capability and easy loading of goods. However, the idea for a car with a multipurpose application can be seen in other classes, especially SUVs.
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Ek Okuma ve İnceleme
Bölümü
Fig. 1: Common body and chassis configurations.
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
A) Unitized body or unibody, in which the chassis parts cannot be
physically removed from the upper body parts. In this case, suspensions and other
mechanical parts are directly fitted (using brackets) to body frame. The main
advantage of such solution is relatively low weight, while the main disadvantage is
a lower dimensional precision of suspension attachment, due to body tolerance and
the lower filtering performance of suspension fittings, reducing the insulation of
vibrations due to road-wheel excitation.
B) Body on frame, where the chassis frame is connected to upper body frame
by bolts with or without the inter-position of rubber bushes. Such a solution
offers the main advantage of allowing the adoption of one chassis for different
body shapes, providing benefits in terms of mechanical parts standardization and
simplification of the assembly process of a mechanical chassis, before being matched
to the upper body. This kind of solution is commonly used for cargo vehicles,
off-road and SUV. The main disadvantage is the increased weight with respect to
configuration A).
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
Reading Text
Unitized (self-supporting) body (Standard
design)
The conventional unitized (self-supporting) body is built up of
hollow sheet-steel components onto which body panels are welded
by welding robots or in multi-spot welding units. Individual
parts can also be glued in position.
Depending upon vehicle type, roughly 5000 spot welds must
be made along a total flange length of 120...200 m. The flange
widths are 10...18 mm. Other parts (front fenders, doors, hood and
luggage-compartment lid) are bolted to the supporting structure of
the body. Other types of body construction include frame and
sandwich designs. Reff: Automotive Handbook
Note:
Unitized Body = Unibody = Self-supporting Body
The frame can be of a uni-body design (Figure 1.1 (a) uni - body), a body on - frame (Figure 1.1 (b)), or a space - frame (Figure 1.1 (c)). The unibody design features stamped panels, while the space - frame is made up
of extrusions and cast parts. The BiW closures are selected based on the
vehicle’s constituent material dent - resistance properties (i.e. yield
strength) while the frame is designed to provide specific torsional and
bending stiffness.
Figure 1.1: Top left: (a) a uni-body design, top, right: (b) truck platform; and bottom right: (c) space-frame design
Mohammed A. Omar, The Automotive Body Manufacturing Systems and Processes, © 2011 John Wiley & Sons Ltd. ISBN: 978-0-470-97633-3
Unibody Construction
The frame is an integral part of the body
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
Body-over-Frame Construction
The body bolts to a thick steel frame
Russell Krick, “Modern Automotive Technology” Sunumu, The Goodheart-Willcox Co.
C) Body with ancillary subframes,
for powertrain and
suspension systems; connections between the subframe and the body can
be either rigid or through elastic bushes. The main advantages are
modularity and the division of the assembly process between parallel lines,
enabling components to be mounted on the sub-frames. The resulting
sub-assemblies can be tested before integration with main body. Moreover,
the relative ease in which elastic and damping devices between subframe
and body can be inserted, provide an improved insulation from noise and
vibration. Again, the main disadvantage is increased weight, but to a
lower extent than configuration B).
sub-frame: takviye şasi, tali çerçeve
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
D) Dual frame body,
in which body and chassis are separate and
connected through elastic and damping bushes. In this configuration, the
structural, safety, propulsion and driving functions are concentrated and
optimized in the chassis, with priority to front and rear crash absorption,
torsional stiffness and resistance to stress induced through the suspension
and powertrain stiff and precise, since the filtering of road-surface induced
excitation is achieved by incorporating elastic connections between chassis
and body. The weight of upper body can be reduced, since the structural
task is limited to its own inertial stresses and to those induced by
transported components, people and load. The same chassis can also be
adopted by different bodies of similar inertia properties. Although the
increase of chassis weight remains a disadvantage, it is partially
counterbalanced by the reduction in the weight of upper body.
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
Referring to body missions previously listed, the
different configurations result in variations of upper
body contribution for just a limited number of functions,
in which the characteristics of body connection with the
chassis is highly relevant:
• structural function,
• insulation and isolation,
• safety and,
• partially, aerodynamics (due to floor contribution).
• The remaining functions are not directly affected .
Focusing on the most common body configuration (C),
through the example of a 2 box mass production body in
white with spot welded steel stamped sheets, it is
appropriate to consider the main stamped parts and
follow a typical assembling process step-by-step, to gain a
deeper understanding of the process used to manufacture
the body, widely applied today.
Lorenzo Morello, Lorenzo Rosti Rossini, Giuseppe Pia, Andrea Tonoli, The Automotive Body, Volume I: Components Design, e-ISBN 978-94-007-0513-5
Kaynak: VW, Otomobil Teknolojisinin Temelleri
www.audi-technology-portal.de
ASF - Audi Uzay Kafesi yüksek mukavemetli bir alüminyum
kafestir. Alüminyum kullanımı önemli bir ağırlık tasarrufu
sağlayarak yakıt tüketimini azaltır ve verimliliği arttırır.
Not: İlk kez 1994 yılında Audi A8’de kullanılmıştır.
http://www.audi.com.tr/tr/brand/tr/Efficiency/efficiency_technologies/road_resistance/audi_space_frame.html
KISA… KISA… KISA…
(A) Unibody construction welds major body panels together to form the frame for attaching
the engine, drivetrain, suspension, and other parts. This type of construction is commonly
used on cars.
(B) With body-over-frame construction, a thick gauge steel frame provides the foundation for
holding other parts. This type of construction is commonly used on large trucks and SUVs.
Figure 1: Two very different methods used to construct modern vehicles: unibody and bodyover-frame construction
Chapter 9 Vehicle Construction, Thomson
Figure 2: Note the space frame construction. Composite (plastic) panels fasten to a
metal inner body structure. Composite panels can be made flexible to resist door
dings and small dents.
Chapter 9 Vehicle Construction, Thomson
Figure 3: This top view of unibody construction shows how
structural members are added to support the engine suspension
and other mechanical systems.
Chapter 9 Vehicle Construction, Thomson
Figure 4: Doors normally have strong steel beams under the door skin to
protect people during side impact collisions.
Chapter 9 Vehicle Construction, Thomson
Summary
 Vehicle classification relates to construction, size,
shape, number of doors, type of roof, etc.
 Three main types of frame construction
 Body-over-frame, unibody, and space frame
 Vehicle commonly divided into 3 body sections
 Front section, or nose section
 Center section, or midsection
 Rear section, tail section, or rear clip
 Vehicle sizes: compact, intermediate, full size
Chapter 9 Vehicle Construction, Thomson