织构拉刀的拉削负载特性建模与验证

Load Characteristic Modeling and Verification for Texture Broaches

针对传统圆孔拉削加工负载建模过程不够清晰,负载特性预测误差较大的问题,将拉刀刀齿上的槽定义成一种表面织构槽,综合考虑刀齿上的织构槽参数、拉削面积圆孔效应和拉削过程多齿接触周期特性,建立了较详细的织构拉刀拉削负载计算模型。基于经典刀齿切削负载理论,提出了具有织构槽拉刀的单齿拉削负载模型;考虑工件圆弧孔形状对拉削面积的影响,进一步优化单齿拉削负载模型;考虑由工件长度引起的多齿接触周期特性,得到一般性的织构拉刀拉削负载计算模型。仿真与实验结果表明,提出的模型能较好地预测实际拉削负载。同时也指出,在拉刀刀齿上开设织构槽可以降低拉削负载,但是开设的织构槽数量并非越多越好,而是存在一个最优值。

Aiming at the problems that traditional model of broaching load is not clearly and the modelingerrors are quite big,the slots on the broach teeth were defined as surface texture grooves herein. A moredetailed computational model of broaching load for texture broaches was provided with a consideration ontexture groove parameters of cutter teeth,the circular holes of workpieces and tooth contacting cycle inbroaching. First of all,based on the classical theory of cutting loads,a single tooth broaching load model fortexture broaches was proposed. Then,the single tooth broaching load model was optimized with the influencesof workpiece circular holes on the cutting areas. Finally,a universal computational model of broaching loadswas obtained by adding tooth contacting cycle effects decided by workpiece lengths. The simulation andexperimental results show that the proposed model may predict broaching load well. Moreover,it is proved thatthe texture groove may be used to reduce the broaching loads. And groove numbers aren.t the more,the better.There is a optimal value for groove numbers.