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对发动机配气机构的凸轮和挺柱进行了摩擦学方面的试验和分析研究,以减少摩擦或防止磨损和擦伤。在专供凸轮和滑动式从动件或凸轮和滚子式挺柱的试验设备上,获得了有关接触载荷、摩擦力、磨损速率或出现擦伤时的临界接触载荷的试验数据。首先,通过对可应用的材料,即淬硬球墨铸铁、中碳钢(S48C)、粉末冶金和陶瓷材料进行摩擦方面的比较,分析材料性能和表面粗糙度对减少摩擦的作用。同时也仔细分析了润滑油粘度或添加剂以及润滑油品质降低对减少摩擦的影响。此外,也查明了由凸轮轴和凸轮工作段的油孔供油或采用滚子式挺柱对减少摩擦的影响。其次,探讨了在采用含碳黑的使用过的润滑油润滑时,磨损速率与凸轮轴转速之间的关系,以评估凸轮从动件材料,即冷激铸铁、氮化硅陶瓷和其他陶瓷对防止磨损的作用。最后,根据对各种材料的抗擦伤性能的评定,确定了最佳的材料配对和合适的表面粗糙度。同时,根据基础油粘度或润滑油添加剂对抗擦伤性能影响的评定,也确定了由抗磨添加剂伯醇二烷基二硫代磷酸锌(1ryZnDTP)或仲醇二烷基二硫代磷酸锌(2ryZnDTP)和摩擦改良剂二烷基二硫代磷酸钼(M_oDTP)或二烷基二硫代氨基甲酸钼(M_oDTP)组成的、效果良好的混合添加剂。此外,还确定了有效防止擦伤的凸轮工作段的油孔位置。最后,总结了这项研究,提出了凸轮/从动件的合理结构或材料,润滑剂性能或添加剂的合理组合,以及可用于改善凸轮和凸轮从动件之间润滑状况的技术方案。
Trials and analysis studies on the cam and tappet of the valve train of the engine were carried out to reduce friction or prevent wear and abrasion. Test data on contact load, friction, wear rate or critical contact load at the time of galling is obtained on a test rig designed for cams and sliding followers or cams and roller lifters. First, the effect of material properties and surface roughness on friction reduction was analyzed by comparing the available materials, hardened ductile iron, medium carbon steel (S48C), powder metallurgy, and ceramic materials. Also carefully analyzed the viscosity of lubricants or additives and lubricants to reduce the quality of the impact of reducing friction. In addition, the influence of oil supplied by the oil hole of the camshaft and the cam working section or the use of the roller-type tappet to reduce the friction was also found out. Second, the relationship between wear rate and camshaft speed when lubricated with carbon-containing used lubricating oil was explored to evaluate the effects of cam follower materials, namely chilled cast iron, silicon nitride ceramic and other ceramic pairs Prevent wear and tear effect. Finally, based on the evaluation of the anti-galling properties of various materials, the best material match and the appropriate surface roughness were determined. At the same time, based on the evaluation of the viscosity of the base oil or the influence of the lubricant additive on the scratch resistance, it was also determined that the anti-wear additive zinc primary dialkyldithiophosphate (1ryZnDTP) or secondary alcohol dialkyldithiophosphate 2ryZnDTP) and friction modifier molybdenum dialkyldithiophosphate (M_oDTP) or dialkyldithiocarbamato molybdenum (M_oDTP) composed of good effect, mixed additives. In addition, the position of the oil hole of the cam working section that effectively prevents chafing is also determined. Finally, the research is summarized and a reasonable structure of the cam / follower, a reasonable combination of lubricant properties or additives, and a solution that can be used to improve the lubrication conditions between the cam and the cam follower are proposed.