braking. Since it takes considerable torque to rotate the
armature, the motor-generator resists drive axle rotation
to help slow and stop the vehicle.
Highway History
Early automobile manufacturers originated in var-
ious ways. In many instances, they evolved from
bicycle makers, carriage and wagon makers, and
other types of industry. Early motorcars were similar to
horse-drawn buggies, but they were equipped with
noisy gasoline-powered engines, steam engines, or
electric motors and batteries. A single lever called a
tiller was used to steer the vehicle and another lever
was used to apply the brakes.
Summary
• The body and frame support, stop, and enclose
the vehicle.
• The engine provides dependable, efficient power
for the vehicle.
• The intake stroke draws the air-fuel mixture into
the engine combustion chamber.
• The compression stroke prepares the fuel mixture
for combustion.
• The power stroke produces the energy to operate
the engine.
• The exhaust stroke must remove the burned gases
from the engine cylinders.
• The computer system uses electronic and elec-
trical devices to monitor and control various sys-
tems in the vehicle.
• The fuel system provides the correct mixture of
air and fuel for efficient combustion.
• Electrical systems operate the electrical-electronic
devices.
• The cooling system maintains a constant engine
operating temperature.
• The lubrication system reduces friction between
internal engine parts.
• Emission control systems reduce air pollution
produced by the vehicle.
• Drive train systems transfer turning force from
the engine crankshaft to the drive wheels.
• Suspension, steering, and brake systems support
and control the vehicle.
• Accessory and safety systems increase passenger
comfort, safety, security and convenience.
Chapter 1 The Automobile 19
Figure 1-26. Various safety systems are used on modern vehi-
cles to protect both the driver and the passengers. This vehicle
is equipped with both front and side-impact air bags. (Audi)
Front
air bags
Side-impact
air bags
Figure 1-27. This hybrid power train contains an internal com-
bustion engine, a motor-generator, and a continuously variable
transaxle. (Honda)
Internal combustion
engine
Motor-generator
Continuously
variable transmission