Research On Automatic Processing Of Precision Pear-shaped Needle

Spinneret plate is an important part in chemical fiber spinning production.Melt is extruded into fibers through spinning holes,so the accuracy and roughness of spinneret holes directly affect the quality of chemical fiber.Microporous,as the most sophisticated and important spinneret holes,play a very important role on the fiber quality.Pear-shaped needle is a finishing tool of microporous,used for extruding microcellular in order to improve the hole wall finish and strengthen the hole material.It can also correct the verticality deviation of the holes in the drilling and reaming.Therefore,it has extremely important function on the spinneret plate production.Pear-shaped needle is ground by ?lmm round bars.The tip is curved,usually work part diameter is 0.15-0.35mm.Because of its small size,complex shape,and high precision(±1?m),at present only the traditional grinding method can meet the requirements.However,since the traditional methods require high technology of the operator,and is difficult to ensure the consistency of processing,it is necessary to study the pear-shaped needle automatic processing.This paper first describes the processing status of pear-shaped needle,then analyzes its existing manufacturing processes,and in accordance with the traditional manual processing methods proposed the overall program of the automatic processing.This research focuses on the analysis of its grinding systems and detection systems,proposes several experimental programs of grinding systems based on different forms of abrasives,and detection systems is determined to use machine vision systems.Secondly,this paper makes a study on the grinding system.According to the superhard abrasive selection rules,we selecte three kinds of abrasives,including electroplated diamond grinding wheel,diamond grinding wheel and diamond oilstone,design their own schemes and verify the feasibility of various abrasives.By comparison,we decide to use the diamond grinding wheel in the pear-shaped needle automatic processing.Then,in accordance with the principles of extrusion,analyzes and designs the shape and size of the pear-shaped needle.Good shape and size can improve the life of pear-shaped needle,and enhance the hole wall roughness.This paper presents suitable shape and its mathematical model,but also a mathematical model for the shape of the pear-shaped needle factory processing,to facilitate comparison between the two.Finally,put forward a creative design of the electromechanical integration equipment of pear-shaped needle automatic processing.The device adopts a motion control card to realize the three axis linkage movement part,and control grinding wheel surface grinding;uses CCD,optical lens and image acquisition card to realize online real-time detection of shapes and sizes of pear-shaped needle.This paper also researches process parameters and machining processes of pear-shaped needle automatic processing on the basis of this device,and gets the matching value of different size wheel,grinding depth and feed rate.By LAB VIEW software programming,control automatic processing and testing,and use the software error compensation methods to reduce errors.After the test,the device is basically able to complete the automatic processing.Compared with the traditional manual processing methods,the device greatly improves the processing repeat consistency,and the operation is simple,without special operation.