论文部分内容阅读
本文曾经1978年10月在汽车学会第二届年会宣读。讨论凸轮轴凸轮型线对发动机气门机构——一个长链状振动系统——的振动、噪声与可靠耐久性之间的关系.对一台顶置气门直列6缸φ101.6×114.3毫米汽油机的两种凸轮型线进行了比较试验,一种型线是原来的设计、组合摆线,另一种型线是新设计的正弦抛物线。试验时在摇臂上贴应变片、测量并记录其应力,然后把记录其应力的胶卷在投影放大仪上校正、放大,作粗略的定量分析。分析的结果与按单质量动力学理论计算值比较。本文计算了气门机构的自振频率,并讨论了提高此频率的方法。测量了气门机构噪声,并作频谱分析。对二种凸轮型线的噪声进行对比。用高速照相法研究了气门弹簧喘振。最后对二种凸轮型线的气门机构进行了在超速运转的拖动的发动机上100小时的可靠性试验。结果是新设计的型线在所有方面都比旧的好;并对气门机构的设计提出几点意见。
This article was read in October 1978 at the second annual meeting of the Automotive Society. Discusses the relationship between the camshaft cam profile and the vibration, noise and reliable durability of engine valve train - a long-chain vibration system.On the basis of a 6-cylinder φ101.6 × 114.3 mm gasoline engine with overhead valve Two kinds of cam profiles were tested, one profile is the original design, the combination of cycloid, the other is the new design of the sinusoidal parabola. Test the strain gauge on the rocker arm, measure and record the stress, and then record the stress of the film on the projection magnifier calibration, amplification, for a rough quantitative analysis. The results of the analysis are compared with theoretical calculations based on single-mass kinetics. This article calculates the natural frequency of the valve train and discusses ways to increase this frequency. Valve body noise was measured and analyzed for frequency spectrum. The two kinds of cam-type line noise comparison. High speed photography was used to study the valve spring surge. Finally, two types of cam-type valve train were subjected to a 100-hour reliability test on an overdriven drag engine. The result is that the new profile is better than the old in all respects; and a few comments on the design of the valve train.