Research Of Multiple Tools Pocket Machining Strategy With Integrating Trochoidal Tool Path

With the wide use of machining center in the industrial manufacture,multiple tools machining of 2.5D pocket,which was considered inefficient in the past,can be achieved because of the automatic tool changing of machining center.The cutting efficiency can be improved by means of multiple tools machining,because of adequately utilizing of cutting capacity of each tool.This paper centers on the research of multiple tools machining of 2.5D pocket with integration of trochoidal and contour-parallel tool path.Its main contents contain:(1)Tool path scheme of integration of trochoidal and contour-parallel tool path is put forward.In multiple tools machining,the machining tools are almost under the status of milling slot.However,the traditional strategy of contour parallel tool path causes large tool engagement when milling slot.Trochoidal tool path can avoid the large tool engagement,but performances poorly in the wide region.To combine the advantages of the above tool path,integration of trochoidal and contour-parallel tool path is proposed.(2)The strategy of machining tools selection based on Ant Colony Optimization(ACO)is proposed.Because selection of the optimal multiple tools must consider the shape of the pocket,material remove rate,tool change and tool retraction and so on.The problem of machining tools selection is transformed into the problem of shortest path in digraph,and ACO is applied to solve it.The proposed strategy is implemented in an example pocket.And it is compared with the other strategies to verify its efficiency.(3)The adaptive feed rate based on the constant safety factor is put forward.In order to improve the efficiency,the cutting load of each machining tool during the machining process is considered,because the machining tools with different sizes have the different allowance of the cutting forces.And the adaptive feed rate of each tool is determined with the constant safety factor which is based on the cutting force.So the cutting capacity is able to be utilized adequately,and the safer machining with multiple tools can be achieved because of the constant safety factor.And the experiment is applied and the cutting force is also measured so as to verify the safety and efficiency of machining with the adaptive feed rate.