共查询到19条相似文献,搜索用时 171 毫秒
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通过对曲面数控加工运动的研究,指出曲面上的曲线也存在着活动的特征标识这一特性,提出了模仿特征标识沿曲面曲线运动的加工法.并以锥形等螺旋角刀槽作为加工实例,应用特征加工法使程序得到最大限度的简化,而且大大地提高编程效率,对一些类似零件的数控加工提供有益的参考依据. 相似文献
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《计算机集成制造系统》2016,(10)
为进一步改善数控加工曲面的表面质量,提出一种针对三角网格曲面的螺旋刀具数控加工轨迹规划方法,在充分考虑刀具轨迹的几何与动力学特性以及三角网格单元特性的基础上,有效减少了抬刀次数,保持了刀具轨迹的连续性。该方法从网格边界轮廓曲线上的刀触点开始逐层偏置,在参数域上对刀触点进行规划,并拟合成螺旋轨迹,将其逆映射到网格曲面上得到螺旋加工轨迹。与传统的截面法和环切法相比,该算法可以生成一条具有边界一致性、轨迹光滑连续的、无需多次进退刀的高质量螺旋加工轨迹。 相似文献
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圆锥滚子双盘研磨工作面求解与形面分析 总被引:1,自引:0,他引:1
根据共轭曲面原理对圆锥滚子双盘研磨加工中研磨盘工作面进行理论求解,运用包络法求解螺旋槽工作面的理论形面方程并分析其形面特征.基于研磨盘对圆锥滚子姿态控制和成形加工的工作要求,分析了上研磨盘、下研磨盘和圆锥滚子三者的空间位置和相对运动关系.采用包络法求解上研磨盘工作形面,建立上研磨盘工作面的理论形面方程.通过数值计算分析螺旋槽工作面的形面特征及螺旋槽与圆锥滚子的接触特征,结果表明,螺旋槽工作面一和工作面二的轴截面廓形都是相对于基准直线的内凹曲线,其中工作面一的轴截面廓形内凹量最大值约为0.012 μm,可简化为直线;螺旋槽工作面是一个轴截面廓形不断变化的复杂螺旋曲面:圆锥滚子与螺旋槽工作面为线接触,接触线为不在圆锥滚子轴截面内的空间复杂曲线,其位置与运动参数β有关.给出了螺旋槽工作面形面参数的精确计算方法并分析了螺旋槽工作面轴截面廓形的变化情况. 相似文献
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对复杂深孔内螺旋曲面进行高精度和高效率加工是复杂深孔加工领域研究的热点问题之一。针对深孔内螺旋曲面加工尚需解决的关键技术建立一种通用的螺旋曲面线型数学模型,为刀具精确设计提供理论计算依据。提出了深孔内螺旋曲面拉削加工方案并进行了拉刀的三维建模,分析论述的复杂深孔内螺旋曲面拉刀设计流程和实例对于成套拉刀设计有参考指导意义。 相似文献
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QingZhen Bi LiMin Zhu YuHan Wang Han Ding 《The International Journal of Advanced Manufacturing Technology》2010,47(5-8):719-730
Flank milling with a taper cutter is widely used in industry. The analytical representation of the envelope surface generated by a conical cutter undergoing rational motion is derived by bringing together the theories of line geometry and kinematics. Based on the projective duality between a point and a plane in line geometry, a cone surface is represented as two pieces of rational quadratic Bézier developable surfaces in terms of the plane coordinates instead of the traditional point coordinates. It provides a way to describe and calculate the envelope surface exactly by analyzing the trajectory of a plane undergoing a two-parameter rational motion. The rotation around the axis of the cone is adopted to ensure that the characteristic curve is located on the same piece of rational quadratic Bézier developable surface of the cone. The degenerate cases that the characteristic curve does not exist are also discussed. Examples are provided, in which the envelope surfaces of a conical cutter undergoing rational Bézier and B-spline motions are computed. The results can be applied to tool-path planning and error analysis for five-axis flank milling machining. 相似文献
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目前采用高速铣削方式加工具有曲面结构的零件非常普遍,而在曲面加工的过程中几何因素对已加工曲面的表面粗糙度具有一定的影响。为了提高加工效率和加工质量,普遍的方法是采用仿真软件。文中以MATLAB为平台,构建双三次Bezier曲面的工件模型,并结合走刀行距和进给量以及切削速度等加工参数,对影响表面粗糙的因素进行分析,同时提出具体的仿真算法,并且在实际应用中加以验证。 相似文献
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Lixin Cao Jian Liu 《The International Journal of Advanced Manufacturing Technology》2008,35(11-12):1053-1064
For given data points on different cylindrical section curves of marine propeller during the design period, the fair fitting method with the least squares of the cubic B-spline curve has been used to form cylindrical section curves with different radius. Then the control points of the cylindrical section curves were used as new data points to process fair fitting in another direction, and the pressure surface and the suction surface of the propeller can be acquired at last. Aims to overcome disadvantages of the present machining method of propeller, such as lower machining precision and efficiency, repeated clamping, and limited machining scope, a new machining method—the second order osculating machining method—has been presented. By using this method, not only the cylindrical cutter and the machined surface can keep line contact, but also the propeller can be machined with one clamping. It’s very suitable for the machining of propeller with larger projected area ratio and the machining precision and efficiency will be improved. 相似文献
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B样条列表曲线直线插补的自适应算法 总被引:1,自引:0,他引:1
给出了一种根据零件加工精度要求,对三次B样条列表曲线进行直线插补,自动生成变步长刀位轨迹的算法,简称自适应算法。该算法当列表曲线曲率大时,使步长变小,反之使步长变大,同时使逼近误差满足要求。该算法稳定、可靠,便于在列表曲线、列表曲面的数控加工中推广应用。 相似文献
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MasterCAM曲面加工一般分为粗加工和精加工,粗加工有七种路径,精加工有十种路径.粗加工是加工出大致形状,使用平刀,精加工是将工件加工成型,使用球头刀.在具体的加工时应选用适当的粗、精加工路径.从三角凸模的曲面特点及加工难点出发,分析了如何使用MasterCAM软件编制合理的刀具路径,使加工质量大为改善. 相似文献
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In the machining of sculptured surfaces, five-axis CNC machine tools provide more flexibility to realize the cutter position as its axis orientation spatially changes. Conventional five-axis machining uses straight line segments to connect consecutive machining data points, and uses linear interpolation to generate command signals for positions between end points. Due to five-axis simultaneous and coupled rotary and linear movements, the actual machining motion trajectory is a non-linear path. The non-linear curve segments deviate from the linearly interpolated straight line segments, resulting in a non-linearity machining error in each machining step. These non-linearity errors, in addition to the linearity error, commonly create obstacles to the assurance of high machining precision. In this paper, a novel methodology for solving the non-linearity errors problem in five-axis CNC machining is presented. The proposed method is based on the machine type-specific kinematics and the machining motion trajectory. Non-linearity errors are reduced by modifying the cutter orientations without inserting additional machining data points. An off-line processing of a set of tool path data for machining a sculptured surface illustrates that the proposed method increases machining precision. 相似文献