用单角铣刀加工圆柱螺旋刃铣刀周齿的计算

用单角铣刀(一刀成)加工圆柱螺旋刃铣刀的周齿,将前面、齿背及刃带同时加工成形。其加工方式为:用铣刀的刀尖挑出工件的前刃面;用铣刀的锥面(角度刃)加工工件的齿背及刃带。对于加工前刃面的计算,是根据已知的刀具旋转面求工件的螺旋面,即旋转面作螺旋运动时曲面族的包络。加工齿背及刃带的计算,是根据已知的工件螺旋面求刀具的旋转面,即螺旋面作旋转运动时曲面族的包络。用干涉法(单角铣刀法)加工螺旋前刃面的计算在资料中已有介绍,但参考资料中的计算是在将单角     

内螺纹梳形铣刀设计验算中的几个理论问题

<正> 圆柱外螺纹和内螺纹都可以用梳形铣刀来加工,而且操作简单,效率高。加工时,刀具和工件轴线彼此平行,又由于刀具是环形面而工件是螺旋面,因此在铣削过程中刀具与工件螺纹牙面便会发生干涉。为了不使刀具与被加工螺纹牙面发生干涉而切坏牙面,同时又为了便于制造铣刀及提高其耐用度,铣刀牙顶还必须要有一定大小的平头宽度,于是铣刀外径尺寸     

铲齿铣刀刃磨后对螺旋槽加工精度的影响分析

螺旋槽多采用铲齿成型铣刀加工,刀具沿前刀面刃磨后刃形不变,但其直径将减小,使计算出的铣刀廓形发生变化,其加工的螺旋面端面廓形将产生误差。给出可求出工件端面的截形坐标计算式和实际加工的工件螺旋面方程式,可推算出工件截形与螺旋面的加工误差。     

锥度螺旋面加工用盘形刀具的轮廓解析法

刀具设计曲面与加工工件的锥度螺旋面接触线为一条空间几何曲线,由此建立了刀具设计廓形的数学模型,提出了锥度螺旋面加工刀具的廓形设计原理,并给出了刀具设计的计算公式。     

基于离散点截形螺旋面加工原理研究

提出了基于离散点的圆柱螺旋面成形刀具计算方法，分别建立了已知螺旋面工件截形离散点数据计算成形刀具廓型的数学模型及已知刀具截形离散点数据计算由其加工的螺旋面工件的数学模型。利用累积三次参数样条法计算螺旋面工件截形及成形刀具廓型各离散点的倾斜角。分析了成形刀具的计算误差，对成形刀具数据型值点以累积三次参数样条进行插值，用双圆弧样条拟合的方法进行光顺处理。实例证明，两模型是正确性的、可行的，能够满足离散点条件下螺旋面高效率、高精度的加工要求。     

加工螺旋槽用指状刀具的截形计算

有螺旋面的工件很多,如螺纹、螺杆、螺旋齿轮、螺旋泵及各类螺旋齿刀具(钻头、螺旋铰刀、铣刀)等。指状刀具一般都用来加工截形对称的螺旋面。加工时,指状刀具安放在螺旋面的齿槽中,它的回转轴与工件螺旋面截形的对称轴重合。刀具作回转运动,工件作参数为P_z(导程)的螺旋运动,此时,刀具切削刃回转面相对于工件螺旋槽的接触线不是平面曲线,而是一条空间曲线,因此,刀具回转面的轴向截形不同于工件任何剖面中的截形,而应是该空间曲线绕刀具轴线回转所得回转面的轴向截形。本文介绍一种比较简单的计算方法,供参考。     

三螺杆泵螺杆成形铣刀廓形设计与研究

通过对空间啮合理论及成形刀具廓形设计的研究,推导出螺杆螺旋面与成形铣刀的接触线方程,利用成形铣削原理和坐标变换原理,将接触线方程转化到刀具坐标系中,建立了基本的铣刀刀刃廓形方程,由此设计螺杆成形铣刀廓形。     

根据指状铣刀齿形计算工件螺旋面廓形的方法

<正> 在生产中,常用指状铣刀来加工圆柱螺旋面。根据已知的工件螺旋面来计算相应指状铣刀轴截面齿形(简称轴截形)的方法在现有文献[1]、[2]、[3]中已研究得相当透彻。但是,根据指状铣刀轴截形来计算工件螺旋面廓形(一般指工件端截面齿廓)则在现有文献中介绍不多。     

基于运动原理计算加工螺旋槽用成型盘铣刀刀具廓型线方法研究

从运动原理出发,通过分析螺旋槽加工中工件、刀具的运动合成关系,在确立相对速度计算方法后,将合成速度的运动特点与工件、刀具加工中的接触条件及共轭特性相结合,推导出盘型铣刀轴向廓型理论计算公式。     

加工具有尖点廓形螺旋面工件的铣刀设计

加工具有尖点廓形螺旋面工件的铣刀设计中南工学院（衡阳４２１００１）刘杰华１．引言按通常方法设计的铣刀加工的螺旋面工件廓形大都是由一段光滑曲线或由曲线与直线光滑连接构成，即构成其廓形的曲线和直线的交接点处存在公切线。但对于某些特殊工件（如压缩机螺杆转子...     

Theoretical modelling of cutting forces in helical end milling with cutter runout

A theoretical cutting force model for helical end milling with cutter runout is developed using a predictive machining theory, which predicts cutting forces from the input data of workpiece material properties, tool geometry and cutting conditions. In the model, a helical end milling cutter is discretized into a number of slices along the cutter axis to account for the helix angle effect. The cutting action for a tooth segment in the first slice is modelled as oblique cutting with end cutting edge effect and tool nose radius effect, whereas the cutting actions of other slices are modelled as oblique cutting without end cutting edge effect and tool nose radius effect. The influence of cutter runout on chip load is considered based on the true tooth trajectories. The total cutting force is the sum of the forces at all the cutting slices of the cutter. The model is verified with experimental milling tests.     

Tool path generation method for multi-axis machining of helical milling cutter with specific cross-section profile

The geometry of helical milling cutter with specific cross-section profile is normally generated with form cutter by the toolpath generating method. The general purpose CAD/CAM software can generate the cutter location file of this class of product only by the sculpturing method. To obtain the flexibility of machining process, this paper presents an interference-free toolpath generating method for semi-finish and finish machining of the helical milling cutter. The method for design and machining of the helical milling cutter is established based on the differential geometry and the enveloping theory. In the finish machining of helical milling cutter, the form grinding wheel profile is firstly derived. To reduce the cost and lead time of the generating method with the form-mill cutter for semi-finish machining, a toolpath generating method which combines the advantages of the generating method and sculpturing method was presented. The cutter location uses ball-nose conical end mill is derived according to the geometric characteristics of the enveloping element. The cutting simulations with solid model were performed to verify the proposed toolpath generation method.     

法向圆弧锥齿轮数控加工研究

研究了法向圆弧锥齿轮的数控加工原理与技术,设计了成形铣刀,给出了刀具与工件的接触条件以及刀具与工件之间的相对运动。斜航式法向圆弧锥齿轮数控加工实验表明,该锥齿轮数控加工原理正确,工艺简单,且加工精度较高。     

Extracting cutting constants via harmonic force components for a general helical end mill

Mechanistic cutting constants serve well in predicting milling forces, monitoring the milling process as well as in helping to understand the mechanistic phenomena of a machining process for a unique pair of workpiece and cutter materials under various types of cutting edge geometry. This paper presents a unified approach in identifying the six shearing and ploughing cutting constants for a general helical end mill from the dynamic components of the measured milling forces in a single cutting test. The identification model is first presented assuming the milling force is measured with a known phase angle of the cutter spindle. When the phase angle of the cutter rotation is not available, as is the case for most milling machines, it is shown that the true phase angle can be identified through the theoretical phase relationship between the different harmonic components of the milling forces measured with an arbitrary phase angle. The numerical simulation and the experimental results for ball and cylindrical end mills are presented to demonstrate and validate the identification methods.     

Face-milling spiral bevel gear tooth surfaces by application of 5-axis CNC machine tool

In order to solve some common problems of CNC-machined spiral bevel gears such as small cutting strip width and poor surface quality, while milled by the ball-end, a machining method of face milling using a disk cutter with a concave end is presented. The research theories are based on the foundation of spiral bevel gears’ geometry structure. Firstly, a bigger diameter disk cutter with a concave end is selected. Then, change the setting order of cutter orientation angles. The functions of cutter tilt and yaw angle are separated, and tooth surfaces machined with big cutting strip width and no bottom land gouge can be expected. Since the cutter yaw angle, determined firstly by cutting contact point, positions in the tooth surface machine, the bottom land gouge interference can be avoided effectively. Then, the tilt angles of the gear pair, both side tooth surfaces, are determined by the theory of sculptured surfaces machined by the flat-end cutter, respectively. As a result, the improved cutting strip width and machining efficiency can be realized. Finally, feasibility of this method is verified through machining experiment and measurement of a spiral bevel gear pair.     

平头立铣刀铣削力模型中积分限的确定方法

在铣削力预报的研究中 ,通常采用的方法是将铣刀沿其轴线方向逐层划分为很薄的微单元 ,对每一个微单元可认为是一个单刃刀具的斜角切削过程 ,通过建立微单元上的切削力模型并沿轴线方向积分来求得总的切削力 ,轴向积分限通常是通过角度换算获取 ,比较繁琐。本文对刀具的几何特征进行了描述 ,建立了求取平头立铣刀铣削力模型角度积分限的通用方法 ,该方法通过分析刀具几何特征和加工类型 ,直接获取角度积分限 ,避免了繁琐的轴向积分限的计算 ,并通过算例验证了该方法的有效性。     

螺旋锥齿轮数控加工中刀盘误差的补偿

在进行螺旋锥齿轮数控加工过程中,用直廓截形代替盘状铣刀刀刃理论截形所产生的偏差会影响螺旋锥齿轮齿面加工精度。针对该问题,分析了螺旋锥齿轮数控加工原理,并在此基础上建立了从刀刃到形成齿面的数学模型;依据空间啮合理论计算盘状铣刀刀刃实际截形,分析并建立了盘状铣刀刀盘半径偏差与齿面误差的关系;进一步推导出刀具实际截形误差的计算过程;最后根据螺旋锥齿轮的加工原理对刀具的误差进行了补偿计算,并对补偿结果进行了仿真实验验证,证明了该算法的可靠性。     

基于有限元仿真的拼接模具铣削用刀具优化

对ABAQUS软件进行了二次开发，以实现拼接模具铣削过程仿真前处理的快速建模。对铣削力、应力和刀具温度进行仿真，并与铣削实验结果对比，验证了仿真模型的准确性。对不同前角、后角、螺旋角及刃口半径的球头铣刀铣削拼接模具的过程进行模拟仿真，采用遗传算法优化铣刀结构，将优化后的结构参数与传统结构参数代入刀具磨损、工件表面质量的对比实验，从而验证了优化的有效性。研究表明，对仿真前处理进行快速建模的二次开发运行成功，模拟结果准确。研究结果为降低制造成本、提高铣刀寿命和工件表面质量提供了理论参考。     

基于Z-MAP方法的球头铣刀铣削力的建模

瞬时刚性切削力的建模是铣削加工物理仿真的基础,然而,球头铣刀的刀齿形状复杂,加工过程中姿态多变,瞬时刚性铣削力的建模难度较大。在考虑刀具姿态调整的情况下,通过齐次坐标变换建立了刀齿的运动轨迹,提出了一种识别刀具和工件瞬时接触区的改进Z-MAP算法,通过计算当前刀齿的参考线与工件的边界面或刀齿扫掠面的交点求出瞬时未变形切屑厚度,并采用非线性回归的方法辨识了切削力系数,在此基础上使用微元积分法建立了瞬时切削力的计算模型。为了验证仿真模型的可靠性,分别进行了垂直加工和倾斜加工试验,试验和仿真结果具有较高的一致性,表明该建模仿真方法是有效的,可以为实际加工中参数的选择和优化提供理论依据。