In recent years, China’s automobile industry has developed rapidly. NVH (vibration and noise) performance has attracted extensive attention of automobile manufacturers. Hypoid gear pair is an important part of rear drive transmission system. The quality of its meshing contact area is the key factor affecting the safety and comfort of vehicle driving. A lot of research has been done on the quality control of the contact area of hypoid gears at home and abroad. Litvin et al. Controlled the transmission error and the quality of the contact area by changing the parabolic transmission error function, so as to achieve the purpose of vibration reduction and noise reduction; Artoni et al. Established a multi-objective optimization problem and adjusted the tooth surface pressure angle error and spiral angle error according to the machine tool parameters, in order to control the contact area in the ideal area; Shih et al. Studied the influence of machine tool processing parameters on tooth surface error and contact area by establishing 45 point tooth surface topological grid diagram; Su Jianxin et al. [5] analyzed the influence of machining parameters of machine tool and cutter head on tooth surface error and contact area by establishing tooth surface mathematical model; Li Tianxing and others developed an automatic identification system of tooth surface error based on the tooth surface detection information, and controlled the tooth surface error through automatic identification and correction.
(1) After heat treatment, the contact area of hypoid gear will deviate greatly. From the distortion law of heat treatment, it can be found that the deviation of contact area of hypoid gear after heat treatment is mainly related to the relative helix angle error of driving and driven teeth.
(2) By comparing the position of contact area under different relative helix angle errors, the correctness of analyzing contact area offset by first-order relative tooth surface error is verified.
(3) The quality control of contact area of hypoid gear after heat treatment is particularly important. In this paper, the method of tooth cutting to compensate the distortion of heat treatment is used to control the quality of contact area after heat treatment. The new gear cutting model is tested from two aspects of tooth surface error and contact area after heat treatment. The results show that this method is feasible and effective.
Taking the hypoid gear pair of the main reducer of the rear axle of a domestic mini car as the research object, by studying the contact area offset principle after heat treatment, using the heat treatment distortion law, the quality of the contact area after heat treatment is controlled by cutting teeth to compensate the heat treatment distortion.
