双头螺杆内旋风铣削技术研究

目前国内螺杆泵双头转子加工方法仅限于盘铣刀外包络铣削,分析了复杂螺旋曲面的形成原理,建立了双头螺杆转子内旋风铣削加工的空间直角坐标系,研究了双头螺杆内旋风铣削切削轨迹,并运用解析几何知识对切削轨迹进行了理论验证,同时利用三维建模软件对内旋风铣削双头螺杆的切削过程进行了模拟仿真,验证了该加工方法的可行性。     

一种特殊空间螺旋曲面的形成过程及求解方法

目前加工单头螺杆普遍采用内旋风铣,2头及2头以上螺杆普遍采用盘铣刀外包络铣削,应用内旋风铣削2头螺杆一直是人们的研究方向[1]。通过从内旋风铣削两头螺杆的应用角度出发,不同于以前的螺旋面是从已知垂直截面方程来求解螺旋面方程。研究已知螺旋面的任意斜截面为圆方程来求螺旋面方程,提出了一种新的解决螺旋面方程的思路。     

基于计算法的螺杆泵螺杆成型铣刀的设计方法

为了提高螺杆泵螺杆的加工效率,仿照螺杆加工过程,利用计算法设计出螺杆成型铣刀。在获得螺杆端面廓形方程的基础上,通过螺杆沿轴线做螺旋运动得到槽旋面方程;利用螺旋面法线与刀具轴线相交条件,求出接触线;接触线作回转运动,进而得到铣刀廓形数据。根据计算原理开发了廓形计算软件,然后依据盘状成型铣刀的结构特点,结合网络技术搭建了螺杆泵螺杆成型铣刀网络设计加工平台,完成了螺杆成型铣刀的设计与加工。     

螺杆数学模型及数控加工铣刀廓形求解

针对单头梯形螺杆转子设计过程复杂,加工难度高导致其表面精度难以控制的问题,在分析梯形螺杆成型原理的基础上,从梯形螺杆基本型线方程出发,避免齿间干涉,应用内凹齿面法,建立梯形螺杆数学模型。结合空间啮合原理,建立螺杆用成形铣刀加工过程中铣刀与工件之间的坐标转换方程。研究螺杆螺旋面几何特性及其与刀具在加工过程中的空间包络特性,提出基于空间啮合法的螺杆截面离散点成形铣刀设计方法,建立刀触点方程,求解铣刀轴向廓形。     

采油螺杆泵螺杆成形铣刀刀刃廓形设计与研究

基于对采油螺杆泵螺杆形状的分析建立了螺杆螺旋曲面方程;利用成形铣削原理和坐标变换理论,从成形铣刀与螺杆工件的相对运动关系出发,建立了基本的铣刀刀刃廓形方程。根据铣刀的实际使用情况,针对成形铣刀用钝重磨后产生的加工误差,进一步建立了具有合适前刀面和恒定后角的铣刀刀刃廓形方程。对廓形方程进行干涉检查,保证了铣刀廓形的正确性。该铣刀刀刃廓形方程为铣刀的设计制造奠定了理论基础,对实际生产具有重要意义。     

螺杆螺旋曲面的廓形设计与仿真

本文主要通过分析螺杆压缩机中阴螺杆的曲面的形成过程,同时根据螺杆的基本参数求出盘铣刀的端面曲线方程,在这个方程的基础上利用matlab编程得到螺杆螺旋槽的端面廓形曲线,通过该曲线建立阴螺杆的三维模型,最后在ADMAS环境下对模型进行运动仿真。研究表明将曲线曲面理论分析和仿真技术相结合,是构造螺杆螺旋面的有效途径。     

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。     

径向铲制成形铣刀的车刀及砂轮的修正

一、前言为了改善切削条件,有些成形铣刀的前角设计成大于零度。当成形铣刀有了前角后,刀齿在轴向剖面内的廓形,就与被加工零件的端面廓形不相同了。因此,成形铣刀在制造过程中,需要求出成形铣刀刀齿的轴     

螺杆加工成型铣刀廓形坐标计算方法

通过对传统螺杆成型铣刀加工轨迹坐标计算方法的进一步推导,获得了一种可以直接由端面坐标点求解铣刀廓形坐标的计算方法.该方法对加工螺杆泵中螺杆转子的成型铣刀轨迹坐标计算具有较好的实用性.     

正交车铣螺杆钻具数控加工的研究

对5LZ165螺杆钻具端面曲线进行了数学建模,在对内摆线建模的基础上求出了螺杆钻具端面曲线的极坐标方程.根据正交车铣加工原理,求出了正交车铣螺杆钻具时球头铣刀刀具中心轨迹的极坐标方程,利用宏程序进行数控编程,在Mazark车铣加工中心上实现了5LZ165螺杆钻具模型的加工.     

食品膨化挤出螺杆的内旋风铣削加工方法研究

传统的膨化挤出螺杆加工方法，其加工质量、加工效率等均不能令人满意。这里在研究三自由度无瞬心外包络法铣削螺杆螺旋曲面的基础上，将无瞬心包络加工工艺与以往内切式旋风成形铣削技术相结合，应用内旋风铣的圆形轨迹包络加工挤出螺杆。这种数控加工技术具有内旋风式铣削的高效性和包络法的高柔性，显著提高了膨化挤出螺杆的加工效率和加工精度。     

基于逆向工程的二刃硬质合金铣刀型线的研究

为了使硬质合金铣刀设计参数由个人经验转变为设计刀具时理论意义上的指导,提高刀具的使用寿命,基于逆向工程理论,提出对二刃硬质合金铣刀的型线方程的研究。经过前期的准备工作,利用万能工具显测量横断面上的点,将数据输入MATLAB软件,利用最小二乘法进行曲线拟合,得出其型线方程由直线和圆弧组成,为进一步精确建模,在ANSYS软件中分析刀具受力、扭矩和摩擦热对刀具影响做好铺垫。     

内旋风式无瞬心包络加工螺杆数控铣削技术

文章针对大型截面廓形为凸形复杂螺杆螺旋曲面的加工,提出了一种高效、高精度、实用的内旋风式无瞬心包络数控铣削技术,并论述了其基本原理及其刀具轨迹的计算方法.     

螺杆转子的旋风式法曲率包络铣削技术

针对石油工业用大型螺杆钻具转子螺旋曲面的数控铣削加工,提出了一种新的旋风式法曲率包络铣削技术。该技术的核心是在每一走刀行程中,实时调整刀具的轴心线绕接触点工件理论曲面外法线向量转动的角度,使铣刀刀尖圆与理论曲面的切触线具有相同的曲率,对理论曲面形成等法曲率的逼近包络。该铣削技术的表面成形精度高,且铣刀切削刃在曲面上的扫描面积大,能显著提高切削效率。在保持加工精度不变的条件下,可大幅度地减少刀具切削     

大长径比螺纹加工的研究

基于对整体加工工艺系统的工艺条件进行转化和改善的研究 ,介绍了一种大长径比大导程螺纹零件的加工方法。当采用常规的工艺方法加工该类螺纹遇到困难时 ,可以将常规的“设法复现螺纹的轴向截形”转换为“设法复现该螺纹的径向截形” ,从而“用复现径向截形角位移序列的方法加工出符合轴向截形定义的所需螺纹表面”。这种新的加工方法使长轴类螺纹零件和深孔类螺纹零件的加工变得简单易行 ,并使该类产品的生产效率和产品质量均有明显提高。随着数控技术和机电一体化技术的飞速发展 ,这种切削加工方法有着广阔的应用前景     

Theoretical model for CNC whirling of screw shafts using standard cutters

Widely increased use of screw components with complex helical surfaces in contemporary machinery makes a huge demand for high-efficiency fabrication of these components. In this paper, a typical whirling process is introduced and the helical surface of a screw shaft is mathematically modeled based on its axial section profile, which is depicted usually by a number of sampled points. Following this, a theoretical approach is proposed to whirling the screw by using standard cutters, aligned with a detailed investigation into related issues including calculations of the cross section profile and the cutting tool location points. In this approach, the helical surface can be generated according to the shaft cross section which is used as the envelope of the cutting-tool motions in the machining process. The machining error is also analyzed with focuses on the axial- and cross section scallop height. Finally a case study is presented, which demonstrates the whole process including CAD models and cutting tool in-process positioning geometry data. The error distribution of the machined component along the profiles is also simulated.     

双螺杆压缩机转子齿形三坐标测量的半径补偿

双螺杆压缩机转子齿形进行三坐标测量机测量时,需要对球形测头半径进行半径补偿.结合转子螺旋曲面的几何特点,对转子型线测量数据点进行半径补偿计算,得到三坐标测量机球形测头真实接触点,再将空间分布的真实接触点旋转到相同横截面上得到转子型线数据点.通过实例验证该方法的有效性,可以应用于双螺杆压缩机转子型线的检测及逆向工程等工作中.     

Spatial filtering characteristics of electrostatic sensor matrix for local velocity measurement of pneumatically conveyed particles

The accuracy of local particle mean velocity measurement with spatial filtering method based on an electrostatic sensor matrix (ESM) is closely related to its sensitivity and spatial filtering characteristics. In this paper, the three-dimensional electrostatic field generated by a point charge in the sensing zone of the ESM is solved by using a finite element method to obtain the spatial sensitivity distributions of the ESM. Further a dimensionless calculation model for the sensitivity of the ESM is suggested based on a Cosine function. The numerical results demonstrate that the spatial sensitivity has a periodic distribution along the axial direction and its spatial periodicity is determined by the axial spacing between two adjacent electrodes. The sensitivity over the central cross-section is localized. The spatial filtering characteristics of the ESM are also investigated and verified by experiments on a gravity-fed rig. These results provide a basis for the optimized design of the ESM.     

MODIFICATION OF GEOMETRY AND TECHNOLOGY OF CYLINDRICAL WORMS

The objective of this research is to develop a new method of grinding process that can efficiently make concave profile of the worm thread smooth. The grinding is carried out using a wheel with curvature profile in the axial plane in the form of an arc of logarithmic spiral. The proposed method will provide maximum line of contact between the tool and the worm with minimum stress concentration at any point. The generating equation of the grinding tool profile and its arrangement with respect to the worm during thread grinding were determined.     

MODIFICATION OF GEOMETRY AND TECHNOLOGY OF CYLINDRICAL WORMS

The objective of this research is to develop a new method of grinding process that can efficiently make concave profile of the worm thread smooth. The grinding is carried out using a wheel with curvature profile in the axial plane in the form of an arc of logarithmic spiral. The proposed method will provide maximum line of contact between the tool and the worm with minimum stress concentration at any point. The generating equation of the grinding tool profile and its arrangement with respect to the worm during thread grinding were determined.