The main functions of the hardware spring are: 1. Control the movement of the machine, such as the control in the clutch; 2. Absorb the vibration and impact energy, such as the buffer in the car and train compartment, the vibration absorption in the coupling, etc.
As an elastic element widely used in automobile, hardware spring has strict requirements on stiffness. Therefore, before the trial production of products, how to calculate the actual stiffness more accurately has become the most concerned problem. After being made, the hardware spring should be pressed or shot peened to improve the bearing capacity of the spring. Hardware spring is a kind of elastic element widely used in mechanical and electronic industries.
When it is loaded, it can produce large elastic deformation and convert mechanical work or kinetic energy into deformation energy. After unloading, the deformation of hardware spring disappears and returns to its original state, and the deformation energy is converted into mechanical work or kinetic energy. The finite element method has been applied to the design of leaf spring because of its high precision, good convergence and easy to use.
Automobile leaf spring has nonlinear and hysteresis characteristics. Large deformation and contact should be considered when using finite element method, that is to say, geometric nonlinearity and state nonlinearity should be considered simultaneously, which will make the calculation difficult to converge, so it needs higher solving skills and analysis strategies.
Hardware spring stiffness, the greater the stiffness, the harder the hardware spring. For the sake of riding comfort, we hope that for the ground impact with high frequency and small amplitude, the spring can be more flexible, and when the impact force is large, it can show greater rigidity and reduce the impact stroke. Therefore, it is necessary for the spring to have two or more stiffness at the same time. Springs with different diameters of steel wires or springs with different pitch can be used. Their stiffness increases with the increase of load.