对虚拟凸轮机构应用于旋耕机刀轴疲劳试验的探讨

在对旋耕机刀轴的快速模拟疲劳试验中,常采用直动滚轮盘形凸轮机构对刀轴施加弯曲载荷,针对传统凸轮机构存在轮廓曲线加工制造困难,精度难以保证,长时间使用后因磨损而使从动件运动失真,且一个凸轮机构只能实现一种预定运动规律而无法根据需要改变等缺陷,采用单片机控制步进电机的运动来虚拟凸轮机构从动件的运动规律,利用单片机的编程功能实现虚拟凸轮机构模拟刀轴的实际受载情况.这种虚拟凸轮机构能方便地实现电信号控制,稳定性好,可靠性高,具有很好的实用价值.

Discussion on virtual cam mechanism applied to fatigue test for rotary tiller shaft

Aimed at several defects associated with conventional fast simulate fatigue test for rotary tiller shaft, such as the additional bending load on the tiller shaft due to directly acting roller-disc cam mechanism, the distortion of follower's motion due to both the difficult processing of the precise profile of the cam and its wear in the process of operation, and in addition that this cam mechanism can only be used for a prescribed pattern of movement without the possibility to alter it in accordance with demand, a stepping motor controlled by monolithic computer is adopted to realize the simulation of movement pattern of the follower of cam mechanism. Actual loading condition of the tiller shaft of that mechanism can also be simulated by using the programming function of the monolithic computer. The signal control can be easily realized by this virtual cam mechanism with good stability, high reliability, and better practical value.