Research on Principle and Power of Air Motor

Researchers have always put the research on lubrication and sealing between piston rings and cylinder liners at the forefront. Based on the analysis of the motion law of crank linkage mechanism of pneumatic motor, the theory of piston kinematics and dynamics was established. The working characteristics of piston ring under specific working conditions were analyzed. Based on this, the continuity equation and fluid momentum equation were used for lubrication analysis. Provide the load conditions and boundary conditions; then based on the average Reynolds equation, taking into account the influence of roughness and the introduction of the shear flow factor and pressure flow factor, established the piston ring - liner lubrication theory.

The oil film thickness was analyzed, and the minimum oil film thickness equation between the piston ring and ring groove of the air motor was established, and the influence of the micro-convex body model, the elasticity of the piston ring on the friction state of the working surface of the piston ring was pointed out, and the process was fully realized. Various factors affecting the lubrication performance of the piston ring of the air motor were considered; the three-dimensional model of the piston group of the air motor was established by three-dimensional software, and the influence of various influencing factors on the lubrication performance of the piston ring was analyzed using Adams/Engine dynamics simulation software, including on different surfaces. Roughness, different barrel height and different axial thickness of the piston ring and other factors, find out the main factors affecting the lubrication performance of the piston ring, based on which the existing pneumatic motor piston rings are optimized, and a pair of upper and lower rings is proposed. The new combined piston ring, and compared the lubrication performance of the new piston ring and the traditional piston ring.

The airtight performance of the piston ring-cylinder liner system also has a significant impact on the integrity of the air motor. On the premise of guaranteeing the lubrication performance, the sealing performance of the piston ring-cylinder liner of the air motor has been studied in detail.

Firstly, a theoretical model of gas leakage is established. The approximate solution of the equation is obtained by the method of Range-Kutta numerical analysis. Based on this, the gas pressure in the cylinder and the change of the gas pressure at the opening of the piston ring are analyzed; The influence of crankshaft speed on the amount of gas leakage shows that the size of the piston ring gap is the main factor affecting the leakage. Finally, the combined piston ring sealing performance analysis and friction power consumption analysis show that the combined piston ring is Under the premise of tightness, it can effectively reduce frictional power consumption and provide new ideas for piston ring structure design.