发动机正时系统RU型和YU型带轮刀具齿廓齿形研究与设计

Research and Design of RU Type and YU Type Pulley Cutter Tooth Profile of Engine Timing System

针对GB/T 10414-2017 《同步带传动汽车同步带轮》标准中没有提供RU型和YU型带轮标准刀具齿形参数的问题,对带轮与刀具齿廓齿形之间共轭谐应关系进行了研究。基于啮合原理,对带轮齿廓的共轭刀具齿面进行包络,利用圆弧曲线对包络曲线离散数据进行数学拟合,确定刀具齿廓数学模型;其次,通过刀具对带轮的二次包络过程发现,加工带轮齿廓齿顶处存在根切。通过带轮根切机理研究,揭示了刀具曲面存在奇异点的原因,提出消除刀具齿廓曲线奇异点的齿廓模型,基于带轮齿廓齿形误差在标准公差范围内,对刀具齿廓参数再设计。

In view of the problem of the GB/T 10414-2017 Synchronous belt drive car synchronous belt pulley standard does not provide the RU type and YU type pulley standard tool tooth profile parameter, the conjugate harmonic relationship between the pulley and tool tooth profile are studied. Firstly, the conjugate tool tooth surface of the pulley tooth profile is enveloped based on the meshing principle, and the discrete data of the envelope curve is mathematically fitted to determine the mathematical model of the cutter tooth profile. Secondly,through the second enveloping process of the cutter on the pulley, it is found that there is an undercut at the top of the tooth profile of the processed pulley tooth profile. Through the study of the mechanism of undercutting, the reason of singularity of cutter surface is revealed, and tooth profile model to eliminate the singular point of cutter tooth profile curve is proposed. The tooth profile error based on pulley is within the standard tolerance range, the cutter parameter is redesigned.