利用Pro／E对加工螺旋槽成形铣刀廓形的设计

从加工螺旋槽成形铣刀廓形设计原理出发，详细讲述了运用Por/技术进行加工螺旋槽成形铣刀廓形的设计原理和步骤，较好解决以往二雏图解法平面谗计作图误差大、计算复杂不直观的缺点，能够准确地做出铣刀回转面与工件螺旋槽的接触线——空间曲线。利用这种方法，通过已知的工件的端面槽型，准确地画出工件的三维图形，根据无瞬心包络法加工原理，就可以在Pro／E的平台上精确地设计出成形铣刀。     

异形螺杆的铣磨复合加工原理

针对异形螺杆加工中存在的表面质量差问题,提出了一种基于无瞬心包络法的异形螺杆铣磨复合加工方法。在对无瞬心包络理论研究的基础上,首先,建立盘形铣刀与异形螺杆之间的包络运动关系,得到盘形铣刀包络铣削异形螺杆的刀触点计算方法;其次,从成形磨削的啮合原理出发,从成形砂轮与异形螺杆之间的空间啮合关系,求解空间接触曲线,并推导出成形砂轮磨削异形螺杆的砂轮廓形计算方法;最后,通过仿真切削加工验证了无瞬心包络铣削法的刀路轨迹和成形砂轮廓形计算的正确性。     

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。     

基于CATIA实现斜齿轮加工仿真

本文在直角坐标系下,根据齿轮啮合原理推导盘形铣刀截形。利用CATIA软件及其内嵌的VB语言,按照仿形法齿轮加工原理,设计斜齿轮成形铣削仿真加工程序。齿形仿真结果与实际测量相符。而且可以通过这种方法,对铣刀是否合格做一下判断,为数控成形铣齿的加工提供了可靠依据。     

螺杆压缩机齿形曲线及其铣刀计算(一)

螺杆压缩机是依靠转子与转子的啮合及转子与机壳的密封来达到压缩气体的目的,故转子齿面的加工精度直接影响螺杆压缩机的效率,因此对于加工其齿面的成形铣刀必须进行精确的计算。刀具刃形的求得,首先确定端面齿形方程,再确定齿面方程,然后由铣刀与齿面相切的条件即可求得铣刀刃形。     

螺杆压缩机盘铣刀刃形的几个问题

目前我国螺杆压缩机转子齿形的加工,绝大部分采用成形盘铣刀法。盘铣刀刃形的计算有所谓等距形线法和等距形面法。当前各厂对这些刃形计算方法还是比较成熟和一致的。但是,许多单位利用这些方法按原本齿形形线计算获得的数据,放大25倍或50倍,绘制成刃形曲线,毫不加修正,直接用光学曲线磨床磨削成刀具刃形样板。进而按此样板靠模成形刀具——成形盘铣刀,结果制作出来的盘铣刀刃形往往达不到齿形的设计要求。因为设备精度和     

基于AutoLISP斜齿轮成形铣削加工的几何仿真

在直角坐标系下，根据齿轮啮合原理，推导盘形铣刀截形，利用AutoCAD内嵌的AutoLISP语言，按照仿形法齿轮加工原理，设计斜齿轮成形铣削仿真加工程序，齿形仿真结果与实际测量相符，为数控成形铣齿的加工提供了可靠依据。     

不铲齿成形铣刀的反求设计

根据国外不铲齿成形铣刀的图片信息 ,从工作原理、刃形计算、结构设计、材料选择等方面进行了反求论证与创新 ,开发出一种新型结构的成形铣刀。这种铣刀勿需铲背 ,经多次重磨仍能保持原有精度 ,使用寿命长 ,并可采用高性能材料制造     

ZC1蜗杆精密磨削加工

基于成形砂轮对工件进行磨削加工的原理,应用空间啮合理论对ZC1蜗杆磨削过程进行理论推导,得出了唔合线方程和砂轮轴向截形的数学模型,利用MATLAB软件计算出砂轮的轴截形并利用此截形数据在配有CNC砂轮修整器的数控螺纹磨床上对砂轮进行修型,用修型好的砂轮磨削工件从而实现对蜗杆的精密加工.     

大型风电传动齿轮成形铣削刀具刃形曲线设计

基于成形原理加工齿轮廓形的盘铣刀是生产大型风电传动齿轮的必备刀具。然而,受加工原理误差影响,传统齿轮盘铣刀只能针对特定模数和齿数齿轮进行加工,刀具通用性差。传统刀具廓形不能够保证被加工齿轮的加工精度与使用寿命,无法最大程度发挥成形铣削的原理优势。基于此建立了齿轮渐开线实际廓形曲线数学模型,分析了共轭齿条顶角相对运动轨迹,建立了齿根过渡曲线方程,依据齿根过渡圆弧空间相对位置,重构了不同形式齿廓曲线的设计方式;基于逆向投影法,以被加工齿轮的各项参数为变量,建立了刀片刃形曲线数学模型,根据刀片空间包络原理,重构了可转位齿轮盘铣刀廓形曲线设计方式;进行了齿轮齿廓及刀片刃形曲线数值分析,研究了大型风电传动齿轮齿廓曲线以及可转位齿轮盘铣刀刀片刃形曲线的主要形式,研究结果为大型齿轮廓形成型加工提供技术支持。     

斜齿特形插齿技术的研究

发展了斜齿特形插齿刀设计制造新方法。利用数值模拟法根据插齿刀齿形计算铲磨砂轮廓形,并能进行逆运算以验证计算结果的正确性。试验证明该方法用于斜齿特形插齿是可行的。     

圆锥形铣刀螺旋槽的数学建模

介绍了一种基于雄铣刀端试形而建立的刀槽螺旋面数学模型的新算法，同时求出了螺旋面上任意一点的切矢量、主法矢量和副法矢量。实例证明，该算法建立的刀槽螺旋面可满足前角、刃带宽度、第一后角和第二后角等参数为常值的设计要求．为铣刀的数控加工提供了前提依据。该算法也适用于其它形状的回转面刀具。     

Study on Rotating Cutters with Different Definitions of Helical Angle

This paper presents the similarities and differences of the design models of the cutting edge and flute section corresponding to the different definitions of the helical angle. The correlative models and simulation results for the cutting edge are presented. The section profile and relative feeding velocities of the grinding wheel in the NC machining of the cutter are deduced. The effects of design and manufacture of the cutter are analysed according to a computer simulation of the flute surface enveloped by the grinding wheel. In addition, the deviation of cutting edge, residual material and lack of land caused by the modified radial feeding velocity are taken into consideration. In order to finish the residual material and rebuild the land of the cutter, a post-process method has been developed in this work. Based on the differences of the results, a rotating cutter that has a constant angle between the cutting edge and generatrix curve has many advantages in its design and for NC grinding. Therefore, it is suggested that the helical angle defined as the angle between the cutting edge and the generatrix curve is a better choice when designing a rotating cutter.     

Parametric modeling and contact analysis of helical gears with modifications

An approach for a mathematical model and contact analysis of helical gears including tip relief, root relief, end relief and longitudinal crowning modification was developed. First, tooth profile equations of non-modified involutes, tip reliefs, root reliefs and fillets were derived after applying gear principles and coordinate transformation to transverse cross section profiles of a rack cutter. Then the intersecting lines between different profiles were solved through by Gauss-Newton numerical method. Parametric modeling program of modified helical gears was obtained to automatically generate exact gear surfaces of tip reliefs, root reliefs, end reliefs and longitudinal crowning modifications via Matlab code. Subsequently, an example of helical gear pair in practical engineering was presented, and the solid model and finite element model with modification were established. Finally, the dynamic contact characteristic of helical gear pair was calculated by three-dimensional dynamic contact finite element method. It is expected that the proposed approach can be applied in analyzing the effect of modification on radiation noise prediction of gear system in further study.     

Design and NC Machining of Concave-Arc Ball-End Milling Cutters

The paper presents a geometric modelling approach for the precision design and NC machining of a concave-arc ball-end milling (CABEM) cutter which is an important tool for mould-making industries. This paper presents systematic models of the cutting edge, helical groove, and grinding wheel design for the NC machining of a CABEM cutter. Both the normal to the revolving axis and the tangent to the groove, are used to derive the required precision sectional profiles of the grinding wheel. In compliance with the maximal sectional radius of the cutter, the profile of the groove section and both the radial and axial cutting speeds of the grinding wheel are computed in sequence. Using the computer simulation results of the groove actually obtained, this paper proposes a method to resolve the problems of the residual revolving surface and the narrow cutting edge strip. This paper is intended to serve as a reference for the design and NC machining of cutters of this type .     

特种回转面刀具螺旋槽的通用几何模型

针对数控磨削螺旋槽的特点 ,提出了基于一般特种回转面刀具刀刃曲线和刀面截形的螺旋槽通用几何模型。该模型采用统一的形式表示螺旋槽 ,为特种回转面刀具的设计和数控加工提供了理论基础。该模型也适用于其它类型的回转刀具     

Modeling and numerical simulation for the machining of helical surface profiles on cutting tools

The classical conjugation and envelope method is very accurate and effective for forward and inverse calculations of grinding helical surfaces. However, this method involves complicated mathematics and requires that the profiles be continuous. It can also result in undercutting or interference to the desired surface profiles. In this paper, a new approach is proposed to simulate the grinding process of helical surfaces on cutting tools. The paper begins with the reconstruction of cutter helicoids from sampled points. Using the recovered helical parameters from the sample points, the cross-sectional profile of the cutter surface is derived using a polynomial curve. A numerical method for calculating the profile of the grinding wheel required for the cutter surface profile is then provided. Finally, an optimization method is presented for solving the problem of inverse calculation to determine the helical surface profile for a given grinding wheel profile and setting parameters. The feasibility of the approach is tested by simulation results, which shows that the proposed approach can eliminate undesired tool-work interferences and undercutting.     

基于Pro/E的非对称渐开线斜齿圆柱齿轮参数化设计及应力分析

非对称渐开线斜齿圆柱齿轮作为一种新型的齿轮,目前对其还没有展开详细的研究。从齿轮范成法加工角度出发,根据齿条型刀具上各曲线部分参数,推导求得非对称渐开线斜齿圆柱齿轮端面主动侧、从动侧的渐开线、齿根过渡曲线方程。以轮齿端面曲线方程为基础,结合三维造型软件Pro/E,建立出非对称渐开线斜齿圆柱齿轮的三维模型。由于建立后的齿轮模型已经参数化,通过更改基本参数,可以快速生成需求的齿轮。同时,以建立的模型为基础,结合有限元分析软件,对对称与非对称渐开线斜齿圆柱齿轮两个特殊啮合位置的轮齿齿根弯曲强度进行了分析、比较。     

具有复杂轮廓特征的实体模型重建方法

基于特征的模型重建是结构类零件实体模型重建的一种重要方法。借鉴正向设计的思想，提出了通过创建截面轮廓线来重建一类具有复杂轮廓特征的方法：首先选取合适的轮廓截面并得到截面轮廓数据点，然后排序轮廓数据点、识别轮廓线型、拟合分段曲线以及提取约束关系，进而实现截面轮廓的约束拟舍，从而得到满足有效约束的截面轮廓线；将截面轮廓线以某种扫掠方式形成实体特征，根据特征之间的依赖关系，运用实体布尔操作将各实体特征“组合”为实体模型。重点研究并实现了其中的关键技术——基于约束的截面轮廓重建方法，并用实例验证了方法的有效性和稳定性。     

A Precision Tool Model for Concave Cone-End Milling Cutters

The paper presents a comprehensive manufacturing model that can be used to produce a concave cone-end milling (CCEM) cutter on a two-axis NC machine. A CCEM cutter possesses many distinct features that are superior in many cases to the traditional flat-end milling cutter for producing parts with multiple sculptured surfaces. Based upon the given design parameters and criteria, the equation of the helical flute groove and the curve of the cutting edge at the end of the helical flute are derived and presented. By using an inverse problem-solving technique, the sectional profile of the grinding wheel, the tool compensation for machining, and the feedrate of both NC axes are consequently obtained. The design results are compared with the measured data obtained from the NC produced CCEM cutter. The satisfactory comparative verification indicates that the tool design and manufacturing model presented in this paper is theoretically sound and it can be automated easily. The proposed method is widely applicable for the mass production of various high-efficiency milling cutters.