Suspension System

SUSPENSION SYSTEM

The suspension system works with the tires, frame or unitized body, wheels, wheel bearings, brake system, and steering system. All the components of these systems work together to provide a safe and comfortable means of transportation.


FUNCTION OF SUSPENSION SYSTEM

      -          Support the weight of the frame, body, engine, transmission, drive train, passengers, and cargo.

      -          Provide a smooth, comfortable ride by allowing the wheels and tires to move up and down with minimum movement of the vehicle.

      -          Work with the steering system to help keep the wheels in correct alignment.

      -          Keep the tires in firm contact with the road, even after striking bumps or holes in the road.

      -          Allow rapid cornering without extreme body roll (vehicle leans to one side).

      -          Allow the front wheels to turn from side to side for steering.

      -          It gives stability to the vehicle

      -          It gives good road holding while driving, cornering and breaking.

      -          It provides comfort

COMPONENT OF SUSPENSION SYSTEM

             1)      Control arm

             2)      Control arm busing

             3)      Strut rod

             4)      Ball joint

             5)      Shock absorber or strut

             6)      Stabilizer bar

             7)      Spring

          1)     Control arm

control arms connect the car's suspension to the actual vehicle frame. They are connected to the frame through a component called brushings, while they attach to the suspension through the ball joint. That allows the vehicle to turn its wheel and pivot, connecting the tire to the car's suspension.

        2)     Control arm bushing


                          

Control arm bushing is used to hold the bolt in place that connects the control arm to the chassis. They are located at the broad end of the control arm to which the part pivots.

        3)     Strut rod

Stabilized single point lower control arm.

Provide caster adjustment.

      4)     Boll joint

Ball joints consist of a ball and socket similar to the hip joint of the human body. Ball joints of your front suspension provide pivoting movement between the steering knuckles and control arms to provide a safe, smooth ride and allow you to precisely control your vehicle.

      5)     Shock absorber

A shock absorber or damper is a mechanical or hydraulic device designed to absorb and damp shock impulses. It does this by converting the kinetic energy of the shock into another form of energy which is then dissipated.

       6)     stabilizer bar

stabilizer bar is a part of many automobile suspensions that helps reduce the body roll of a vehicle during fast cornering or over road irregularities. It connects opposite (left/right) wheels together through short lever arms linked by a torsion spring.

      7)     spring

Any spring, whether it's a leaf, torsion or coil spring, must compensate for irregularities in the road surface, maintain the suspension system at a predetermined height and support added weight without excessive sagging.

TYPES OF SPRING IN SUSPENSION SYSTEM

1)      coil spring

2)      leaf spring

3)      air spring

4)      torsion spring

       1)     Coil spring

A coil spring, also known as a helical spring, is a mechanical device which is typically used to store energy and subsequently release it, to absorb shock, or to maintain a force between contacting surfaces. Coil spring is mostly use in cars & bikes

The coil spring is made of round spring steel wound into a coil. Because of their simplicity, they are less costly to manufacture and also have the widest application. This spring is more flexible than the leaf spring, allowing a smoother reaction when passing over irregularities in the road. Coil springs are frictionless and require the use of a shock absorber to dampen vibrations. Their cylindrical shape requires less space to operate in. Pads are sometimes used between the spring and the chassis to eliminate transferring vibrations to the body. Because of its design, the coil spring cannot be used for torque reaction or absorbing side thrust. Therefore, control arms and stabilizers are required to maintain the proper geometry between the body and suspension system. This is the most common type of spring found on modern suspension systems. Coil spring mountings are quite simple in construction.

       2)     Leaf spring

A leaf spring is a simple form of spring commonly used for the suspension in wheeled vehicles.

the center of the arc provides location for the axle, while loops formed at either end provide for attaching to the vehicle chassis. A leaf spring can either be attached directly to the frame at both ends or attached directly at one end, usually the front, with the other end attached through a shackle, a short swinging arm. Mostly use in heavy duty vehicle like trucks.

Types of leaf spring

1)      Elliptic

2)      Semi-elliptic

3)      Three quarter elliptic

4)      Quarter elliptic

5)      transverse

       3)     Air spring

The air suspension system is an air-operated, microprocessor-controlled system. This system replaces the traditional coil spring suspension and provides automatic front and rear load levelling. The air springs are made of rubber and plastic, support the vehicle load at the front and rear wheels.

       4)     Torsion Bar

The torsion bar consists of a steel rod made of spring steel and treated with heat or pressure to make it elastic so it will retain its original shape after being twisted. Torsion bars, like coil springs, are frictionless and require the use of shock absorbers. The torsion bar is serrated on each end and attached to the torsion bar anchor at one end and the suspension system at the other end. Torsion bars are marked to indicate proper installation by an arrow stamped into the metal. It is essential that they be installed properly because they are designed to take the stress in one direction only. The up-and-down movement of the suspension system twists the steel bar. The torque resistance will return the suspension to its normal position in the same manner as a spring arrangement.

The torsion bar is basically a length of metal rod anchored at one end to the car body and at the other end to the suspension lower link. As the wheel passes over a bump the bar twists. It returns to its original position when the bump is passed and restores the car to its normal drive height.

The bar resist twisting action and act like a conventional spring.

Types of suspension system

1)      Conventional suspension system

2)      Independent suspension system

      1)     Conventional suspension system

In this suspension system. The wheels are fitted on beam type which are attached to the chassis frame through road springs. In this type of suspension, the effect on one wheel is directly transmitted to the other side wheel through the axle.

2)      Independent suspension system

Independent suspension is any automobile suspension system that allows each wheel on the same axle to move vertically (reacting to a bump on the road) independently of the others.

In this system the suspension for each wheel in an independent unit and in free from the effect of one another. There will be no effect of road shocks on the vehicle directly.

TYPES OF INDEPENDENT SUSPENSION SYSTEM

1)      McPherson Strut Suspension.

2)      Double Wishbone suspension.

      1)     McPherson Strut Suspension.

The MacPherson strut is a type of automotive suspension system that uses the top of a telescopic damper as the upper steering pivot. It is widely used in the front suspension of modern vehicles and is named for American automotive engineer Earle S. MacPherson, who invented and developed the design.     




2)  Double Wishbone suspension.

In automobiles, a double wishbone suspension is an independent suspension design using two wishbone-shaped arms to locate the wheel. Each wishbone or arm has two mounting points to the chassis and one joint at the knuckle.