Book Title: Automobile Suspension System and Steering Classroom Manual
Author(s): Don Knowles
Publisher: Cengage Learning
Edition: Published on 2010
PDF Size: 44 Mb
The Fifth Edition of Today’s Technician: Automobile Suspension System and Steering Classroom Manual by Don can help you learn about the processes and components of traditional suspension systems. It also includes thorough information about new suspension technology being used in vehicles nowadays.
The suspension system of a vehicle is responsible for keeping the wheels in contact with the ground, absorbing the vibrations, and movement caused by the wheels in the vehicle movement, so that these blows are not transmitted to the frame. All the elements of a car, such as an engine and all its transmission system must be mounted on a rigid frame. It is easy to deduce that we need a solid structure to support these organs.
The structure that will achieve this robustness is called a frame and it is formed by two strong panels and several crosspieces, which ensure its rigidity. Today in the manufacture of passenger cars, the chassis system is used, also called a self-supporting or monocoque body, in which the body and the frame form a single assembly.
The term suspension system refers to the set of components that connect the wheels to the chassis of a vehicle allowing relative movement between them. The suspension is constituted by a system of metal springs (or less frequently of rubber, tires or magnetic) that isolate the irregularities of the road to the bodywork, whose oscillations are stopped by means of shock absorbers, generally hydraulic, that transform the kinetic energy in heat. Additionally, it has a set of structural elements responsible for operating springs and shock absorbers guiding the wheels in their travel. This set of elements can be designed in very different ways, giving rise to different suspension systems.
The automobile suspension systems seek the compromise between two antagonistic requirements; the maintenance of the stability of the vehicle subjected to powerful forces during its displacement and comfort of the passengers. To achieve an acceptable compromise, the suspension isolates the body from the irregularities of the road by suspending it on metal springs, or less frequently rubber, tires or magnetic, while their oscillations are stopped by means of shock absorbers, generally hydraulic that transform the kinetic energy into calorific.
Additionally, the suspension of almost all automobiles uses a series of structural elements that actuate springs and shock absorbers, guiding the wheels in their journey.
Any type of automotive suspension is designed so that the path traveled by the wheel along the path of the suspension – wheel motion – is known in advance – fixed path -. However, this displacement, despite being known, may not be ideal due to technical or economic conditions.
Ideally, the wheel should move under all kinds of circumstances in a vertical plane perpendicular to the ground. However, matching the prefixed displacement with the ideal is a very complex task, given that the elements of the suspension that guide the wheel are not fixed to the ground but to the body, which moves continuously with respect to it. In addition, dynamically the wheels are sometimes to the interaction of different combined forces -par of acceleration and braking, centrifugal and lateral force, etc-, whose effects on the components and the route of the suspension must be scrupulously planned to ensure the control of the vehicle. Along with the suspension, the transmission system in the automobile is also very important to control the smooth shifting of gears and balance of the vehicle.
Elements of the Automobile Suspension System:
Springs: These are elements placed between the frame and the closest to the wheels, which directly pick up the irregularities of the ground, absorbing them in the form of deformation. They have good elastic properties and absorb mechanical energy, avoiding indefinite deformations.
Shock absorbers: The deformation of the elastic means, as a consequence of the irregularities of the ground, gives rise to oscillations of the whole set. When the irregularity that produces the deformation disappears and, if the oscillations are not stopped, it would balance the whole body. This brake, in number and amplitude, of the oscillations is carried out by means of the shock absorbers. See more automobile pdf books.
Other elements of automobile suspension system:
- Trays: its purpose is to control the longitudinal movements of the wheels, due to the effect of strong exits and braking, in addition to freely allowing the vertical movements of the wheels, due to the irregularities that the road presence.
- Bumpers of rubber: it has a purpose to avoid the direct blows of metal with metal when the oscillation pass of the normal ranges.
- Swivels: its purpose is to freely allow the vertical movements of the wheels, as well as the angular movements of the steering.
- Tensioner or tensioner bar: its purpose is to control the longitudinal movements when instead of tray they bring suspension arm.
- Padlocks: they are intended to allow the free extension of the steel sheets of the package of springs, as well as its curvature.