Research On Rapid Shape Adjusting And Forming Process Automation In Multi-point Forming

The main idea of the paper is to develop large-scale Multi-point Forming(MPF)equipment and improve forming process automation in MPF for sheet metal. Andthe principle, methods and correlative technique on shape-adjusting about MPFequipment were mainly studied, and surface modeling and shape-adjusting softwarewas developed. The result has been successfully applied to the control system ofshape adjusting in MPF equipment for sheet metal and achieved automatization ofshape adjusting at present. Based on that, the feed-in device and the method offorming error correction were deep studied. Through above research, mainconclusions are achieved : 1. Research on the shape adjusting princilpes and methods of MPF equipment. The paper has successfully solved shape-adjusting problems of the large-scaleMPF equipment. Serial and parallel shape adjusting methods were put forward. Themain character of serial shape adjusting is that the elements are adjusted one by one,then the time of shape adjusting will be farther long as the number of elementsincreases. The main character of parallel shape adjusting is that all the elements areadjusted at the same time, the time of shape-adjusting is decided on the max value ofthe adjuste distance among the elements. The basic principle of serial shape adjusting is that the elements are adjustedone by one with a manipulator, which can move in X and Y axis direction. Toincrease the shape-adjusting speed, more element adjusting devices are set on themanipulator, then the manipulator can adjust more elements in each position. Serialshape adjusting procedure mainly includes manipulator moving, jogged angle v吉林大学博士研究生学位论文adjusting, electromagnet clutching, element height adjusting and electromagnetdeclutching etc. All the motions of manipulator are drived by servo motor, whichcan improve the speed of shape adjusting and precision of shape adjusting. A PWMvotage control technique was is employed in electromagnet circuit. A high votagewas applied to the electro- magnet at first, and then switched to low votage. Theelectromagnet not only can acquire enough attracting force during the long course,but also can work well in low temperature. In parallel shape adjusting, each element matches one adjusting device which iscalled CNC driving unit (control unit). A distributing control system is composed ofall the control units joined by industrial field bus with a master computer, then allelements can be adjusted at the same time. 2. Research on serial shape adjusting technology and development of serial shape adjusting software. An industrial workstation was adopted as the kernel of serial shape-adjustingcontrol system, and some interface circuits, such as servo motor cards and I/Ocontrol cards, were extended. A set of multi-axis CNC system was composed ofservo motors, servo drivers, and encoders etc. The system is used to drive themanipulator precilionly; The I/O control card is mainly used to control and check thecondition of electromagnet. Development of shape-adjusting software is another pivotal technology ofcontrol system. Its main function includes surface design of the element groups andadjustment of the element height and equipments maintenance. Shape-adjustingcontrol software is developed by VC++. It includes following pivotal technologysuch as multi threading technology, OpenGL three-dimensional graphics disposaltechnology, call back of WDM and DLL and software graphics interface disposal,etc. Surface design of element groups is the first step of the process of sheet metalforming by MPF press, and it is the same to tradition forming method in whichvi摘要shape of solid die must be designed before sheet part is formed. But surface designof element groups has its specialties that the final result of surface design is tocaculate the height of every elemen...