Analysis Of Kinematics And Dynamics And Experimental Research For Parallel Bonder Of IC Die Bonder

High speed and accuracy IC die bonder is one of the main equipments of IC package. With the development of IC industry, the tendency of picking speed and position accuracy of IC die bonder is getting higher and higher. Therefore, how to increase its picking speed and position accuracy has become one of the hot research topics in recent years. At present serial mechanism are used in most kinds of bonder in china and foreign, however, its quality and inertia of moving parts are very heavy, which goes against further increasing its picking speed and position accuracy. Meanwhile, based on the strong structure rigidity, high moving precision and position accuracy, light weight and so on, the parallel mechanism has aroused scholar's widespread interest all over the world. At present stage, this mechanism has been mainly applied to the areas of machine tools and robots. According to the working requirements and characteristics of IC die bonder, one kind of new bonder that uses the parallel mechanism has been designed in this thesis, then the kinematics and elastic dynamics rules of this mechanism have been researched. Finally an experimental prototype has been carried out for verification. The following problems have been studied and solved:Firstly, according to the moving trace and working requirements of the bonder, suitable forms of the parallel mechanism have been chosen, while based on the summaries of all its possibe forms, one kind of new plane-double-sliders parallel bonder has been designed. This mechanism uses the forms of translational pairs and rotational pairs, while the servo motors are mounted on its rack, therefore the quality of moving parts are light and their inertias are small, which is advantageous for the improvement of picking speed. Then the working space of the mechanism has been analyzed, and the optimized mechanism model has been established by using the methodology of Global Operating Performance. Finally based on actual need of existing TP900 automatic IC die bonder, the structural parameters of this parallel bonder have been determined.Secondly, the kinematics of the parallel bonder of the IC die bonder has been analyzed, and the kinematic equations of this mechanism have been established, and its working position, the inverse and direct solution, velocity and acceleration have been deduced at the same time. Comparing all kinds of speed curves which are possibly used in the parallel bonder, one of them has been selected as motion controlling curve of this mechanism. What is more, the optimized moving curve of the die bonder has been obtained. Therefore the bonder moves smoothly, its impact and vibration are small and its moving time is comparatively short.Thirdly, elastic dynamics analysis of the parallel bonder of the IC die bonder has been studied and discussed in detail, and its elastic dynamics model has been established by the way of Kineto-Elastodynamic Analysis (KED). As one kind of high speed parallel mechanism, the IC die bonder is moving fast, whose moving rods are light, moving precision and position accuracy requirements are extremely high, so the influence of elastic deformation on precision must be seriously taken into account. The moving platform and the rack of the parallel bonder have been assumed as rigid body and each moving chain has been assumed as elastomer in this thesis. Supposed the coupling effect between rigid motion and elastic deformation to be ignored, the elastic kinematic equations have been established. Corresponding numerical solution of these equations have been obtained in the whole working space through the method of Newmark integral, and Input Motion Programming Algorithm has been used to compensate the moving error of the die bonder. Results prove that the error of the IC die bonder is reduced rapidly, and its precision reaches micron level, so it can realize excellent precision of moving trace.Fourthly, the error model of the parallel bonder has been discussed in this thesis. the position error model of the mechanism has been established by using the direct-differential method and each kind of effect factors to the moving precision and position accuracy has been analyzed. There are a lot of factors that influence the moving precision and position accuracy of the IC die bonder, such as driver moving error, clearance of moving pairs, thermal deformation error and elastic error produced by elastomeric deformations of the mechanism parts etc. Considering different influence coefficients to the mechanism error, through the mechanism error model, the key factors that greatly influence the mechanism error have been determined, the principal methods to increase the mechanism precision have been clear, and the accurate and reliable principle to improve the bonder precision has been also provided. Based on the position inverse solution including moving error of the bonder, the position error compensating model has been developed in this thesis. By modifying the angle of axeses of left and right driving motors, its position error might be within the stated scope.Finally, based on the above research, an experimental platform of the parallel bonder of the IC die bonder has been manufactured. Parameters such as moving precision, position accuracy and picking speed have been measured by using image recognition technology. The experimental results indicate that the designed parallel mechanism can meet the working requirements of the IC die bonder and each performance index has reached the design standards.