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[Music]
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the suspension joins a car's Wheels to
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its body
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absorbs and dampens the impacts of
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uneven Road surfaces
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dampens the vibrations of the body and
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wheels
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allows relative motion Between the
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Wheels and the vehicle
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and transfers forces acting on the
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wheels to the body
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suspension is classified in two
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dependent suspension
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independent suspension
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Sami independent suspension
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a system in which two wheels on an axle
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are firmly attached to one another is
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known as a dependent suspension system
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as a result of their independence the
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wheels Tilt at the same angle as one
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travels over uneven Terrain
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the wheels are attached to a rigid beam
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except for some SUV models this style of
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suspension is rarely found in
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contemporary automobiles it is widely
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used in trunks though
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independent suspension
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an independent suspension system is a
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system in which two wheels of an axle
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are independent of each other
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when the car goes over a bump one of the
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wheels can change its position without
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affecting the other wheel
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different types of independent
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suspension systems are possible with the
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McPherson Strat being the most popular
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the majority of current automobiles have
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independent suspension systems on the
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front axle
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automobiles in the middle and top tiers
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frequently feature independent
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suspension systems on the rear axle as
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well
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semi-independent suspension
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a semi-independent suspension system is
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an intermediate link between the
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dependent and the independent systems
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a torsion beam is used in place of the
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rigid beam in this Arrangement and
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because of its capacity to twist it
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lessens the dependence of the wheels on
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a single axle
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it is installed in the rear axle of many
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lower tier and mid-tier cars
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now let's examine the structure of the
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front independent suspension using the
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example of the McPherson strut and the
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double Wishbone suspension
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these suspension systems include
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a wheel hub in this instance the Hub is
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mounted on a steering knuckle
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suspension lengths control arms and
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beams
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Springs
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shock absorbers
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an anti-roll bar
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suspension mounting elements
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note that one part can have more than
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one function for example the strut in
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the McPherson suspension system
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may serve as a shock absorber and a
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control arm
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let's go through the structure of a
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semi-independent suspension
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its key element is the torsion beam
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the wheel hub is mounted directly on the
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beam
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let's take a closer look at the
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suspension components
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wheel hub
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the wheel hub joins the wheels to the
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control arms enabling their rotation
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you can see a wheel hub and a hub
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bearing installed in the steering
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knuckle
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The Hub is attached to the brake disc
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and the wheel and is mounted on the
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steering knuckle via the hub bearing
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allowing the wheel to rotate
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the steering knuckle has fastening holes
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for various components such as the brake
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caliper and control arms
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as well as the tie rods that turn the
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steering knuckle
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the rear suspension uses a rear knuckle
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sometimes the wheel hub and the hub
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bearing are mounted directly on the beam
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moving on
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the appropriate movement of the wheels
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in relation to the body is insured by a
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variety of suspension lengths arms and
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beams
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they also transmit lateral and
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longitudinal forces that are applied to
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the wheels
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in this case such Parts include the arms
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and the strut of the McPherson system
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to ensure a flexible connection the arms
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are outfitted with the rubber bushings
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and ball joints which we'll discuss
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later
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well the strut uses an upper strut mount
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with a bearing
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Springs
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spring deformation occurs as a result of
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outside forces
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when the outside influences seize they
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take on their original shape
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car springs primarily absorb and
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transmit vertical forces that act on the
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wheels
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their deformation allows to smooth down
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the impacts of uneven terrains on the
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vehicle
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apart from coil springs some designs use
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torsion bar Springs leaf springs and air
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Springs
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at torsion bar Spring is a metal rod
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that can twist
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it is rarely seen in cars but is common
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in multi-axle and tracked vehicles
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a leaf spring is made up of several
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Metal Sheets
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if we talk about automobiles such
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Springs are only used in some SUVs but
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they are widely used in truck vehicles
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in their spring is a rubber cylinder
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filled with air
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due to its compressibility air serves as
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a spring in this design
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although pneumatic suspension systems
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with their Springs offer exceptional
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performance they are mostly employed on
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high-end automobiles due to the
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complexity of the entire system and the
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high cost of Maintenance it is widely
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used in trucks and buses
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coil springs are the most frequently
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used Springs in automobiles because they
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provide acceptable driving
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characteristics and are reasonably
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priced
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moving on to shock absorbers
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shock absorbers absorb and dampen
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vibrations and shocks including spring
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oscillations that affect the body and
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the wheels improving traction and
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comfort
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you can see a suspension system with
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shock absorbers working to absorb and
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dampen vibrations
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the shock absorbers aren't functioning
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right now and you can see that without
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damping the body begins to swing and the
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wheels experience vertical oscillations
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a typical shock absorber for a passenger
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car is constructed as a telescopic tube
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with an oil-filled working cylinder
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the Piston valves allow the oil to go
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from one chamber to another when the
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shock absorber is in use
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the resulting resistance dampens the
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oscillations
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the shock absorber in a McPherson
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suspension system also functions as a
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control arm
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such shock absorbers are strengthened to
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withstand lateral forces and are known
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as struts
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anti-roll bar the anti-roll bar is a
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U-shaped torsion bar it can be connected
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to the suspension's moving Parts
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directly or via anti-roll bar links
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the center portion of the bar is
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attached to the frame or body with
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anti-roll bar bushings
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if both Wheels cross a bump the
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anti-roll bar rotates in the bushings
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if just one wheel does the anti-roll bar
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twists causing the other wheel to move a
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little as well making the wheels
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somewhat dependent on each other
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what use does the anti-roll bar serve
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it enhances vehicle handling and safety
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by reducing body roll during cornering
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as you may know when a car turns at a
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greater speed its body tilts due to the
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centrifugal force
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this causes the inside Wheels to lift
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off the road and lose traction which may
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ultimately result in the loss of control
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over the vehicle
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the features of the at a roll bar in
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this instance allow it to twist and
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lessen the roll of the vehicle
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suspension mounting elements
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the suspension mounting elements connect
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all suspension components to each other
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the body or frame
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since many parts of the suspension move
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relative to each other most of them
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employ flexible joints
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these comprise rubber bushing
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ball joints
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Opera strut mounts and anti-roll Bar
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Bushings the subframe is used as an
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intermediate fixture element
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a rubber bushing is made up of two metal
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sleeves jointed by a rubber insert
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the rubber insert gives the bushings the
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stroke appropriate for this design and
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allows them to partially dampen the
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suspension's vibrations
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rubber bushings are fitted into another
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component and the inner sleeve is bolted
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rubber bushings are a common component
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found in various suspension parts such
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as arms torsion beams
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shock absorbers
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and the subframe
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the ball joint
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a typical ball joint in the suspension
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system is made up of a ball stud fitted
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in a metal housing with a plastic insert
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in between
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the ball joint can swing and rotate
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allowing the components it connects to
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move relative to each other
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it joins the steering knuckle with the
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control arms
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the ball joint can be detachable or it
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can be integrated with the control arm
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to form a single assembly
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ball joints are also found in anti-roll
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bar links
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the outer tie rod and the inner tie rod
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the strut mount
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shock absorbers are attached via rubber
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bushings
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the upper strut mounts in the front
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shock absorbers however Feature A
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different kind of fixture
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in case of the McPherson strut the upper
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strut mount must allow the strut to
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rotate as its bottom is rigidly attached
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to the steering knuckle
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the rotation is made possible thanks to
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the bearing known as the strut bearing
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to contain minor movements of the shock
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absorber and reduce vibrations the strut
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mount also uses rubber joints which are
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similar to rubber bushings
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other front suspension systems may look
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similar but they might not include a
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shot absorber that can rotate and the
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upper Mount will then lag the strut
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bearing
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moving on
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the anti-roll bar bushing is quite
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similar to the rubber bushing
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it features a cut that enables it to be
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mounted on the anti-roll bar before
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being attached to the body or frame the
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anti-roll bar can freely rotate within
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the bushings
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subframe
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the subframe is a rigid frame that
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serves as a support for some suspension
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parts
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it can be mounted on both the front and
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rear axle
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it can also be used as a support for the
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engine transmission steering mechanism
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and other systems
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in the absence of a subframe the
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suspension is attached directly to the
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body
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as a last Point let me mention that
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tires also take comp and partially
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dampen surface irregularities
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the more air attire contains the better
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it can absorb any road defects but the
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worse the handling
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our examination of the automobile
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suspension systems is now complete
