adrift汽车悬架英文

2021年1月20日发(作者：gesundheit)

Suspension Principle Of Work
When people think of automobile performance, they normally think
of horsepower, torque and zero- to-60 acceleration. But all of the power
generated by a piston engine is useless if the driver can't control the car.
That's why automobile engineers turned their attention to the suspension
system
almost
as
soon
as
they
had
mastered
the
four-stroke
internal
combustion engine.

The job of a car suspension is to maximize the friction between the
tires and the road surface, to provide steering stability with good handling
and to ensure the comfort of the passengers. In this article, we'll explore
how car suspensions work, how they've evolved over the years and where
the design of suspensions is headed in the future.

Vehicle Dynamics
If a road were perfectly flat, with no irregularities, suspensions wouldn't
be necessary. But roads are far from flat. Even freshly paved highways
have subtle imperfections that can interact with the wheels of a car. It's
these
imperfections
that
apply
forces
to
the
wheels.
According
to
Newton's laws of motion, all forces have both magnitude and direction. A
bump in the road causes the wheel to move up and down perpendicular to
the
road
surface.
The
magnitude,
of
course,
depends
on
whether
the
wheel is striking a giant bump or a tiny speck. Either way, the car wheel
experiences a vertical acceleration as it passes over an imperfection.

Without
an
intervening
structure,
all
of
wheel's
vertical
energy
is
transferred
to
the
frame,
which
moves
in
the
same
direction.
In
such
a
situation,
the
wheels
can
lose
contact
with
the
road
completely.
Then,
under the downward force of gravity, the wheels can slam back into the
road surface. What you need is a system that will absorb the energy of the
vertically
accelerated
wheel,
allowing
the
frame
and
body
to
ride
undisturbed while the wheels follow bumps in the road.

The
study
of
the
forces
at
work
on
a
moving
car
is
called
vehicle
dynamics, and you need to understand some of these concepts in order to


appreciate
why
a
suspension
is
necessary
in
the
first
place.
Most
automobile
engineers
consider
the
dynamics
of
a
moving
car
from
two
perspectives:

Ride - a car's ability to smooth out a bumpy road

Handling - a car's ability to safely accelerate, brake and corner

These two characteristics can be further described in three important
principles - road isolation, road holding and cornering. The table below
describes
these
principles
and
how
engineers
attempt
to
solve
the
challenges unique to each.

Principl
e
Definition
Goal
Solutio
n
Road
Isolation
Absorb
energy
from
The
Allow
road
bumps
vehicle's
the
vehicle
and
ability
to
body
to
ride
dissipate
it
absorb
or
undisturbed
without
isolate
road
while
causing
shock from the
traveling
over
undue
passenger
rough roads.
oscillation
compartment
in
the
vehicle.
The
Keep
the
Minimi
degree
to
tires in contact
ze
the
which
a
car
with
the
transfer
of
maintains
ground,
vehicle
contact
with
because
it
is
weight
from
the
road
the
friction
side
to
side
surface
in
between
the
and
front
to
various
types
tires
and
the
back, as this
of
directional
road
that
transfer
of
changes and in
affects
a
weight
a
straight
line
vehicle's
reduces
the
Road
Holding


(Example:
The
ability
to
tire's grip on
weight of a car
steer,
brake
the road.
will
shift
from
and accelerate.
the rear tires to
the
front
tires
during braking.
Because
the
nose of the car
dips toward the
road,
this
type
of
motion
is
known
as

The
opposite
effect
--

--
occurs
during
acceleration,
which
shifts
the
weight
of
the
car
from
the
front
tires
to the back.)
Minimize
Transf
body
roll,
er
the
which
occurs
weight
of
as
centrifugal
The
the
car
force
pushes
ability
of
a
during
Corneri
outward
on
a
vehicle
to
cornering
ng
car's
center
of
travel a curved
from
the
gravity
while
path
high
side
of
cornering,
the
vehicle
raising
one
to
the
low
side
of
the
side.
vehicle
and


lowering
the
opposite side.
A car's suspension, with its various components, provides all of the
solutions described.

Let's
look
at
the
parts
of
a
typical
suspension,
working
from
the
bigger
picture
of
the
chassis
down
to
the
individual
components
that
make up the suspension proper.

The Chassis
These systems include:

The
frame
-
structural,
load-carrying
component
that
supports
the
car's engine and body, which are in turn supported by the suspension

The
suspension
system
-
setup
that
supports
weight,
absorbs
and
dampens shock and helps maintain tire contact

The
steering
system
-
mechanism
that
enables
the
driver
to
guide
and direct the vehicle

The
tires
and
wheels
-
components
that
make
vehicle
motion
possible by way of grip and/or friction with the road So the suspension is
just one of the major systems in any vehicle.
Springs
Today's springing systems are based on one of four basic designs:

Coil
springs
-
This
is
the
most
common
type
of
spring
and
is,
in
essence,
a
heavy-duty
torsion
bar
coiled
around
an
axis.
Coil
springs
compress and expand to absorb the motion of the wheels.

Leaf springs - This type of spring consists of several layers of metal
(called
first
used
on
horse- drawn
carriages
and
were
found
on
most
American
automobiles
until
1985.
They
are
still
used
today
on
most
trucks
and
heavy-duty vehicles.

Torsion bars - Torsion bars use the twisting properties of a steel bar
to provide coil-spring-like performance. This is how they work: One end
of a bar is anchored to the vehicle frame. The other end is attached to a
wishbone, which acts like a lever that moves perpendicular to the torsion
bar.
When
the
wheel
hits
a
bump,
vertical
motion
is
transferred
to
the
wishbone
and
then,
through
the
levering
action,
to
the
torsion
bar.
The