摘要
随着高压开关电器柜行业的迅猛发展,对母线成形加工设备的精度与效率提出了较高的要求,而目前国内市场上的传统母线折弯设备大都为手动或半自动控制,其折弯角度控制精度及加工效率都较低,很难满足母线大批量加工生产的要求。因此,设计、开发出一种价格较低、精度较高的全自动母线折弯设备具有十分良好的市场前景。
本文以昆明昆开专用数控设备有限公司生产的KJW303S半自动数控液压母线折弯机为试验样机,以铜、铝母线板材为研究对象,通过对母线板材在样机上的加载弯曲及卸载成形的数据进行分析并通过有限元数值计算方法对母线弯曲成形的全过程进行模拟,分析并得到了母线在折弯加工时的弯曲、回弹及成形的规律。总结出了在母线进行折弯加工过程中必然经历不稳定回弹、稳定回弹及失效这三个阶段,同时利用得出的这一母线弯曲、回弹及成形规律设计出了一套高精度的母线折弯成形控制方案。
本文根据新提出的母线折弯成形控制方案设计了一种全新的带有实时角度测量的折弯机机头,该机头通过安装在跟随母线弯曲而产生旋转的两支测量半轴上的高精度光电式旋转编码器能实时的将母线的弯曲角度传送至控制系统,其角度测量精度达到了0.1°,在国内外的母线折弯机中处于较高水平。
在本文所设计的母线折弯机控制系统中采用了PLC作为控制核心及触摸屏作为人机交互界面。与传统的PLC控制程序开发不同,本文的控制系统设计是通过数控代码的思想并采用了编码与解码的方式,在PLC中构建了一套数控加工代码的核心解码程序。同时,还利用了触摸屏中的宏程序功能使触摸屏不仅能完成参数的输入工作,而且还能直接将用户所输入的折弯控制参数转换为加工控制代码并将其传送至PLC的特定存储区中。该设计不仅更易于程序的扩展与维护,而且还大大降低了系统对PLC存储器容量的要求。
本文通过对母线的弯曲、回弹及成形的研究所提出的母线折弯成形控制方案及根据该方案所设计的折弯机控制系统经装机调试运行,结果表明本系统功能完善,性能优良,使母线单次折弯的成形精度到达了0.3°,能完全满足高压电器柜行业母线加工制造的要求,提高了母线的加工精度与生产效率。
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.
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