The Structure Design And Test Research Of The Piston Pin Bore

The thesis states current status of pin bore construct design of internal combustion engine piston, breakage form of piston pin bore, and the concerned knowledge of construct design of pin bore, etc. It is based on the above knowledge, bring forward a new theory that is stress distribution on pin bore surface and calculation method of curved face of pin bore configuration, using finite element analysis method to calculate mechanical deformation of pin bore, piston temperature field and thermal deformation of pin bore, and it also depicts the verification method of rationality of pin bore construct. Taking design of L375 piston configuration for example, it analyzes and calculates the construct value of each part on curved face under different pin bore configuration designs: (1) Pin bore theoretic diameter, (2)Equation of outer curved face of pin bore, (3)Equation of inner curved face of pin bore, (4)Stress distribution on pin bore surface, (5)Fatigue safety factor of each part on piston, etc. According to the analysis results , define a optimized pin bore surface design, which will guide piston pin bore design in future.The main content of the thesis is as follows:1,Summarize essence rules of piston pin boss configuration and pin bore surface design, including horizontal and vertical profile rules of pin bore, analyze and specify the definition method of pin bore fitting clearance.2,Analyze piston force receipted and mechanical & thermal deformation of pin bore, ascertain calculation method of mechanical formation, thermal deformation and integrated deformation of pin bore.3,Analyze and summarize different designs of pin bore, and make comparisons of different design on decreasing maximum value effect of pin bore surface stress.4,Analyze and summarize wrecking form of piston pin bore, and analyze the reason of different breakage form.5,Bring forward new theory of stress distribution on pin bore surface, present a calculation method of pin bore curved face configuration, using the theory to design L375 piston, L375 piston have passed stability test in engine test, and it has...