Study On The Mechanism Of Busbar Bending And Development Of Control System Of Busbar Bending Machine

With the swift and violent development of electric appliance cabinet industry of HV switchgear, the more excellent performance is demand on precision and efficiency of busbar bending equipment. Howevery, the traditional busbar bending, at present, is mainly manual or semi-automatic control in the domestic markets. With low control precision and machining efficiency of bending angle, it is hard to meet the needs of mass production of the busbar. So developing and designing a Full-automatic busbar bending machine with high precision and low cost has the good market prospect.This thesis takes a semi-automatic busbar CNC hydraulic press brake KJW303S as experimental prototype, which is made by Kun Ming Kun Kai special NC Equipment Co., Ltd, regards the plates of Copper busbar and aluminum busbar as research subject, On the basis of data analysis for loading bending and unloading forming of busbar plates on the prototype,and the simulation by numerical calculations of finite element method on the whole process of busbar bending forming, the laws of bending, springbacking and forming are obtained in the busbar bending processing. Then, this article summarizes that the busbar necessarily experienced three stages characterized by unstable springback, stable springback and failure in bending processing. Meanwhile, a high accuracy busbar forming Control Scheme is presented due to the laws of bending, springbacking and forming.According the busbar forming control scheme proposed above, a new bender head with real-time angle measure is designed. This bender head can transfer the busbar bending angle to the control system instantly by the high accuracy electro-optic rotary encoder mounted on the two measure semi axles which revolve with the busbar bending. The angle measurement accuracy reaches 0.1°, which is comparatively high in the domestic and foreign busbar bender. In this paper, the control system of the busbar bending machine use PLC as the central core and touch-screen as man-machine interface. Compared with traditional PLC program, the control system in this paper is designed by NC code processing thoughts and used the coding and decoding way, and constructs a NC machining code core decoding program in PLC. Meanwhile, the usage of macro of touch screen can not only finish the input parameters, but also directly converts bending control parameters inputted by users to the machining process code which is sent to of particular storage areas of the PLC. This design is much easier to the extension and maintenance, also, significantly reduces the requirements of the storage of PLC.The test run result of the control system that designed by study the busbar banding and it's springback in this paper, shows the designed bending control system performed well, and the precision of angle controlling reached 0.3 degree, which can fulfill the requirements of the industry of HV Switchgear, and enhance the precision and production efficiency of the busbar manufacturing.