① Control the movement of machinery, such as valve springs in internal combustion engines, control springs in clutches, etc. ② Absorb vibration and impact energy, such as buffer springs under cars and trains, and vibration-absorbing springs in couplings. ③Store and output energy as power, such as clock springs, springs in firearms, etc. ④Used as a force measuring element, such as a dynamometer, a spring in a spring scale, etc. The ratio of the load to the deformation of the Precision Spring is called the spring stiffness. The greater the stiffness, the harder the spring. Spring is an elastic element widely used in the mechanical and electronic industries. The spring can produce large elastic deformation when loaded, and convert mechanical work or kinetic energy into deformation energy. After unloading, the deformation of the spring disappears and returns to its original shape. Deformation energy is converted into mechanical work or kinetic energy.