The role of springs in automobiles
Friends with cars all know that springs play a very important role in the suspension system of cars, so what about car springs in other places? What is the effect? The leaf spring is the most widely used elastic element in automobile suspension. It is composed of a number of alloy spring sheets of equal width but unequal length (the thickness can be equal or unequal), which is approximately equal in strength. elastic beam. When the leaf spring is installed in the suspension of the car, and the vertical load it bears is positive, each spring leaf is deformed by force, and there is a tendency to bow upward.
At this point, the axle and frame are approaching each other. When the axle and the frame are far away from each other, the positive vertical load and deformation of the leaf spring will gradually decrease, and sometimes even reverse. The end of the second piece is often bent into a roll ear, which is wrapped around the main piece of the roll ear, which is called a wrap ear.
In order to allow the relative sliding of each sheet during elastic deformation, a large gap is left between the main sheet's wrapping lug and the second sheet's wrapping lug. In some suspensions, the two ends of the leaf spring are not made of roll ears but use other support connection methods, such as rubber support pads.
Coil springs are the most used springs in modern cars. It has strong shock absorption ability and good riding comfort; the disadvantage is that the length is large, the space is occupied, and the contact surface of the installation position is also large, which makes the layout of the suspension system difficult to very compact.
Since the coil spring itself cannot bear the lateral force, a complex combination mechanism such as a four-link coil spring has to be used in the independent suspension. For the consideration of riding comfort, we hope that for ground shocks with high frequency and small amplitude, the spring can be softer, and when the impact force is large, it can show greater rigidity and reduce the impact stroke. Therefore, it is necessary for them to Springs have two or more stiffnesses at the same time.
Springs with unequal wire diameters or springs with unequal pitches can be used, and their stiffness increases as the load increases. Leaf springs are mostly used in vans and trucks, and are composed of several slender springs with different lengths. Compared with the coil spring, it is simpler in structure and lower in cost, and can be compactly assembled on the bottom of the vehicle body, and friction occurs between each piece during operation, so it has a damping effect. But if there is severe dry friction, it will affect the ability to absorb shock. Modern sedans that value ride comfort are rarely used.