The working principle and refitting method of the

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Working principle and refitting method of automobile suspension system spring

the significance of suspension system is two: isolating the unevenness of road surface to make driving more comfortable; Keep the tires in contact with the road when driving on uneven roads. The only purpose of the improved suspension for the flying car party is to improve the handling

coil springs are the most commonly used springs in suspension systems because they are easy to manufacture, high performance and efficiency, and low price. The definition of spring in physics is to store energy. When we apply a fixed force to the spring, it will deform, and when we remove the force, the spring will tend to return to its original state. However, the amplitude of the spring's vibration when it rebounds will often exceed its original length, and the free vibration caused by the spring's rebound will not be slowed down until there is friction resistance, which is usually the task of the shock absorber

general springs are so-called (linear springs), that is, when the spring is under force, its compression deformation follows the physical (Hooke's law): f=kx, where f is the force, K is the coefficient of elasticity, and X is the deformation. For example, a linear spring with a force of 40kg will cause 1cm compression, and then each additional force of 40kg by 1cm will increase the amount of compression. In fact, there are other pressures on the suspended spring. Even when the spring is fully extended, the spring will still be subjected to the tensile strength pressure of 4.5.3 so that the spring itself can be fixed on the car

in the traditional suspension design of spring and shock absorber, the spring plays the role of supporting the vehicle body and absorbing the impact of uneven roads and other forces on the tires, and the so-called other forces here include the forces caused by acceleration, deceleration, braking, turning, etc. More importantly, in the process of eliminating vibration, it is necessary to maintain the continuous contact between the tire and the road surface and maintain the tracking of the car. Improving the contact between the tire and the road is our primary consideration to improve the handling

the main function of the spring is to maintain the comfort of the car and keep the tires in full contact with the ground. Using the wrong spring will have a negative impact on the driving quality and handling. Imagine that if the spring is completely rigid, the suspension system will not work. When encountering uneven roads, the car jumps up, and the tire improves the energy utilization efficiency of the plastic granulator process and the prevention and control of environmental pollution. It also completely leaves the ground. If this happens when accelerating, braking or turning, the car will lose its trackability. If the spring is very soft, it is easy to see (sitting on the bottom), that is, the suspension stroke is exhausted. If the bottom sitting occurs during cornering, it can be seen that the elastic coefficient of the spring becomes infinite (there is no compressed space), and the body will produce immediate weight transfer, resulting in the loss of traceability. If this car has a long shock stroke, it may be avoided (sitting at the bottom), but the relative body will also become very high, and a high body means a high body center of gravity. Body customers will have such concerns when they haven't bought the experimental machine. The height of the center of gravity has a decisive impact on the handling performance, so too soft shock absorbers will lead to obstacles in handling. If the road is absolutely flat, then we don't need springs and suspension systems

if the road surface is rough, a relatively soft spring is required to ensure the contact between the tire and the road surface, and the travel of the spring must also be increased. The choice of spring hardness depends on the ruggedness of the road surface. The more rugged the spring is, the softer the spring is. But how soft it is is is a key problem. Usually, this requires the accumulation of experience, and it is also an important topic for all car factories and teams

generally speaking, soft springs can provide better comfort and maintain better tracking when walking on rough roads. However, when driving on ordinary roads, it will cause the suspension system to swing up and down, affecting the control. In cars equipped with good aerodynamic components, the soft spring will change the height of the car when the speed increases, resulting in different handling characteristics at low speed and high speed

modification of spring

the modification of spring is mainly to improve the handling, that is, to use a harder spring or a shorter spring. The spring controls many factors related to the control, and the change of the spring will cause very complex changes in the control characteristics. In terms of the increase of hardness, it can improve the rolling inhibition ability of the suspension and reduce the rolling of the body when cornering. The reduction of vehicle height can reduce the center of gravity of the vehicle body at the same time, reduce the weight transfer of the vehicle body during cornering, and improve stability. The reduction of car height can also take into account the aesthetic effect

progressive spring

the spring has two main functions: one is to act as a buffer between the suspension system or chassis and the ground, that is, to maintain comfort, and the other is to keep the tires close to the ground when the car passes through uneven roads. To achieve these two conflicting goals, different elastic coefficients are needed. Keeping the tyre on the ground has a decisive impact on the handling. We need a hard spring setting to keep the tyre on the ground. When the paint contains a large amount of VOC (volatile organic compounds) to the bumpier road surface, we need the softer spring setting. To achieve these two goals at the same time, the only feasible method is to use a (nonlinear spring) with a composite elastic coefficient, which is generally called a progressive spring

progressive spring can increase the elastic coefficient with the compression of spring, which is quite difficult in design and manufacture. When driving on bumpy roads, the elastic coefficient will increase to maintain the stability of the car body. The initial elastic coefficient is soft, which is used to improve the adhesion of tires when passing through bumpy roads. The gradually stiffening spring can prevent the suspension or the spring from sitting on the bottom. This allows the use of springs with a lower height than the original to reduce the center of gravity of the vehicle body, and maintain the lowest and shortest suspension travel when passing through bumpy roads, so as not to sit on the bottom

to achieve a progressive spring is to make a nonlinear spring whose elastic coefficient will change with compression. Therefore, most of the current progressive springs use unequal pitch springs or coil diameter changing springs. When the unequal pitch spring is compressed, it will produce local line to line contact, so that the effective number of turns will change, resulting in the change of the elastic coefficient K. The most direct way to change the elastic coefficient is to change the diameter of the upper and lower coils of the spring

reduce the body

the most important way to improve the handling is to reduce the center of gravity of the body, so as to reduce the weight transfer and rolling of the body during cornering. The simplest way to reduce the body is to start with the spring. Using short springs is the easiest and fastest way. (end)

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