【作者】 宋俊全；

【导师】 冯连勋；

【作者基本信息】 北京化工大学 ， 机械设计及理论， 2003， 硕士

【摘要】 随着塑料工业的发展,尤其是塑料建材的发展,锥形双螺杆挤出机得到了迅速发展和广泛应用。螺杆几何构型及参数直接影响挤出机的生产能力和挤出产品的质量。因此,实现螺杆的造型设计和工程制图的参数化,对于提高设计质量、缩短设计周期、降低设计成本以及实现CAM,是一项非常有现实意义的工作。本文从锥形双螺杆几何结构入手,对与锥形螺杆设计相关的大量资料、经验数据、经验公式以及螺杆基本结构参数进行了分析研究,为锥形双螺杆的计算机辅助设计奠定了理论计算依据,为设计软件的开发提供了可靠的保征。本文借助于CAD的VBA(Visual Basic for Application)三维造型及计算分析功能,对锥形双螺杆三维实体造型的端面曲线进行了分析修正。同时,利用CAD的VBA二次开发技术,方便有效地实现了锥形双螺杆的三维参数化实体造型。基于实际的螺杆加工应用,结合锥形双螺杆几何尺寸约束和二维工程图的特点,成功地开发了对应于三维实体造型的二维工程图的参数化绘制,且两者间可任意转换,以满足不同的需要。本文用Visual Basic6.0驱动AutoCAD图形开发环境,通过VB友好的窗口界面实现人机对话,完成了对AutoCAD绘图命令的参数化控制。本课题的研究,对机械CAD技术在国内塑料机械行业中的应用,尤其是在螺杆设计中采用CAD技术具有一定的参考价值和推动作用,对本专业领域CAE(CAD和CAM)软件开发也具有一定的指导意义。更多还原

【Abstract】 With the development of plastics industry, especially in plastics constructional materials, conical twin-screw extruders are expanding rapidly and applied widely, and geometry configuration of the conical twin-screw directly influences throughput of extruders and quality of extrusion. Therefore, it is significant to implement parametric 3D solid modeling and engineering drawing for improving quality of design, shortening period of design, reducing cost and realizing CAM.In this paper, according to the geometry configuration of conical twin-screw and a great deal of experiential data of design in conical twin-screw, analyzing a series of experiential formula about design of conical twin-screw and discussing parameters of essential screw configuration, it is the theoretical basis of CAD for conical twin-screw and reliable foundation on researching its applied software.By using function of 3D solid modeling and analysis about VBA (Visual Basic for Application) of AutoCAD, the theoretical end curve of conical twin-screw for 3D solid modeling is modified. At the same time, the parametric 3D solid modeling is availably realized by programming technique of VBA for CAD software in this paper.Based on the practical use and manufacture about conical twin-screw, and considered the geometrical dimension parameter of conical twin-screw and the character of 2D engineering drawing, the parametric 2D engineering drawing relative to its 3D solid modeling software is triumphantly achieved. In the course of implement, the 3D solid modeling and the 2D engineering drawing may be expediently selected in order to satisfy with different demands.The AutoCAD drawing model-place is executed in the circumstance of Visual Basic6.0, and the parametrically drawing and modeling are under the control of a friendly User Interface, which is realized by using VB programs.Anyhow, the achievements of this paper made a good reference and development for an application of the Mechanical CAD to domestic plastics machinery, especially in using CAD to design screws. It also found a good basis for developing specialized software of CAE (CAD and CAM) in other fields.更多还原