Research On Wire Deflection And Tension Control Of Diamond Wire Travelling System

Consolidation abrasive wire cutting technology,also called diamond wire saw,is a technology using consolidation abrasive to cut hard and brittle material,which has developed rapidly in recent years.This technology is widely applied into the sawing process of hard and brittle material such as glass,silicon crystal,quartz crystal,hard alloy,ceramic and rare earth magnetism.The machining requirements are demanding higher and higher.On one hand,silicon crystal cutting develops to the direction of large diameter cutting,contour cutting and profile cutting.On the other hand,silicon crystal cutting requires that workpiece after cutting has very high processing quality and finished product rate.These requirements greatly increase the machining difficulty of hard and brittle material like silicon crystal,and also put forward high request of machine tool and processing equipment.This paper makes transformation about wire travelling system and control technology on diamond wire saw machine tool.A detection and control device that allows for feedback control according to the change in wire projection position is developed to solve the problem that wire deflection affects the shape precision of workpiece during the profile cutting process.Also,a tension detection and control device is developed to solve tension variation problem during machining process and to improve the cutting stability and machining precision of reciprocating winding diamond wire saw.The main work is as follows:(1)Components of the wire deflection detection and control device as well as the tension detection and control device are designed by Solidworks and Autocad softwares.Components processing technology is compiled and components have been processed to finish the transformation of wire travelling system.(2)This paper makes research on the reason of wire deflection during the cutting process,proposes a method for solving this problem using wire deflection detection,called light projection method,and develops a detection and control device which can effectively control the wire deflection phenomenon in the process of diamond wire cutting process.(3)This paper makes research on diamond wire tension variation during reciprocating wire winding machining process.This paper analysis the main reasons of wire tension variation,develops tension detection and control device to solve tension variation problem during machining process which can effectively control the problem of tension instability during the reciprocating wire winding machining process.(4)This paper uses the wire deflection detection and control system to perform validation tests with polycrystalline silicon materials.The test shows that,this detection and controlling device can effectively control the wire deflection phenomenon in the process of diamond wire cutting process.The roundness of a polysilicon with 20 mm thickness and ?20 mm diameter can be controlled within 0.05 mm,enabling significant improvement in the cutting shape precision and cutting stability.(5)This paper uses the tension balance control system to make cutting effect verification tests with polycrystalline silicon materials.Test shows that: detection and control device can effectively control the problem of tension instability during the reciprocating wire winding machining process,the positive and negative wire tension fluctuation can be controlled within 0.6N,and the cutting efficiency,cutting surface roughness and machining dimension accuracy are greatly improved.