铲磨交错齿梳形螺丝铣刀的方法

铣螺纹的方法有两种:一种是用圆盘形的铣刀,铣螺距大的螺纹;另一种是用圆柱形的梳形铣刀,铣螺距小的螺纹。根据铣螺纹要求的精度和光洁度,梳形铣刀的齿形又分为铲磨和不铲磨的两种。后者由於齿形表面光洁度差,并且热处理后齿形和齿距的变形不再进行修正,因而它所铣成的螺纹无论是精度或是光洁度都比不上铲磨齿形的梳形铣刀所铣成的螺纹好。 铲磨梳形螺丝铣刀的齿形非常困难,特别是螺距很小(1.25公厘以下)和很宽的梳形铣刀。因为铲磨这种铣刀,砂轮齿形的尖端很容易磨钝,而铲磨成的铣刀螺纹齿形达不到要求的深度,必须经常修整砂轮。 梳形铣刀…     

螺旋槽梳状铣刀的设计与制造

用梳状螺纹铣刀加工螺纹,生产率较高。为使铣削螺纹时切削比较平稳,可采用螺旋槽梳状铣刀。一、螺旋槽梳状铣刀的设计螺旋槽梳状铣刀的齿背加工是在铲齿车床上进行的(见图1)。铲背时,若第一个刀齿在A点开始铲削,因铣刀槽是螺旋的,则在铲刀移动一个螺距P铲制第二个齿时,应在A′点铲削,这样在轴向截面     

错齿梳状铣刀

我厂的0.5模数梳状铣刀如图1所示,它比普通梳状铣刀加工生产率高,铣削平稳,排屑顺畅,便于修磨。下面对该刀具的制造工艺及生产中的具体问题,作一简要介绍。     

数控螺纹梳刀铣削加工参数化编程

1 引言 本公司开发的可转位螺纹梳刀铣刀片系列产品,推向市场就得到了用户的好评,但是大多数用户对螺纹梳刀铣削加工接触时间不长,不理解其运动过程及轨迹,所以在加工编程出现一些问题,未能充分发挥螺纹梳刀铣削加工的优势.     

梳形铣刀的多线磨加工

齿杆梳形铣刀是用于加工油泵调速齿杆梳形齿条的刀具,刀具齿形精度要求高,见图1。从铣刀加工工艺过程可知,铲磨是决定该铣刀精度的关键。原采用单线砂轮磨削铣刀齿形如图2。第一圈齿磨完后,将砂轮架移动一个齿距,磨削第二圈齿,这样连续往复多次进行磨削,直到齿距和齿深都达到图纸要求。由于机床上齿轮、丝杠的传动误差、拖板的进给系统误差和磨头部分轴向窜动及径向跳动误差等都会直接影响齿距和齿深精度,虽然在加     

普通车床铲齿夹具及工艺

我厂研制成功一种“普通车床铲齿夹具”,将此夹具装在普通车床上,可以代替铲齿车床对各种成形铣刀、梳状螺纹铣刀、齿轮滚刀、蜗轮滚刀的齿背以及成形锪钻的型面进行铲削加工。     

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     

梳形铣刀的应用

介绍了梳形铣刀铣削螺纹加工的刀具选择、切削参数确定和常见问题处理，并给出了合理的刀具路径，为推广应用这种高效率的螺纹加工方法奠定了基础。     

电火花加工螺纹

众所周知,加工螺纹孔时,通常都使用加工中心或攻丝设备,但有时也用人工攻丝.加工外螺纹时,一般都使用车床、丝锥和梳形铣刀等进行加工.     

以满足市场需求为目标,工具行业大力进行刀具新产品的开发

<正> 随着我国社会主义市场经济的发展,给我国工具行业的发展注入了巨大的活力。“七五”期间,工具行业通过技术引进、技术改造和科研攻关,开发了大量的新产品,如TMG10、CABS模块式镗铣床工具系统、MAX-I型硬质合金可转位铣刀系统、2(1/2)″～8″新结构高效弧齿锥齿轮铣刀盘、加工淬硬齿轮用硬质合金刮削滚刀、硬质合金弧齿锥齿轮铣刀盘、硬质合金插齿刀、深孔加工刀具、高精度硬质合金石油管螺纹梳刀、硬质合金可转位车削工具系统、整体硬质合     

Histochemical and ultrahistochemical localization of heavy metals in calf organs

Cadmium, zinc, selenium, and copper were administered, singly or in combination, orally or subcutaneously. Experiment I included 32 calves of both sexes; six received Cd (two groups), Zn, Cd, and Zn, and Cd and Se (two groups) and one group was a control. In Experiment II (21 bulls), three were given Cd, Cd, and Cu, and Cd and Zn, respectively, and one group was a control. For light microscopy, in Experiment I the highest amounts of silver granules were present in the samples of liver, small intestine, and vesicular gland of all the exposed groups; in Experiment II the most affected organs were liver, kidney, and small intestine. For electron microscopy, in Experiment I, after administration of Cd and Zn, the highest amounts of granules were seen in the cytoplasm of hepatocytes and cells of the proximal and distal renal tubules and the lowest amounts were found in glandular cells of the pancreas. Administration of Cd and Se resulted in the presence of large numbers of granules in the nuclei and nucleoli of spermatogonies. In Experiment II, ingestion of Cd and Zn in feed led to the appearance of highest amounts of granules in the nucleoli, nuclei, and cytoplasm of cells in testes, kidneys, and pancreas. Following Cd intake, the highest accumulation of granules was observed in the nucleoli of hepatocytes and cells of the proximal and distal renal tubules. Combined Cd and Cu produced the highest number of granules in cells of the proximal and distal renal tubules and in the nucleoli and nuclei of germinal epithelium.     

可展开固体反射面机构设计及运动学分析

针对传统固体反射面机构主反射面型面精度和收拢率较低的问题,设计了一种可展开固体反射面机构。首先,提出4种固体反射面机构可展单元构型并对其机构自由度进行分析,对比分析构型方案优缺点确定构型方案4作为可展单元基础构型,并对其结构和展开原理进行详细设计。通过D-H坐标变换建立该机构可展单元的运动学模型,根据几何约束条件建立机构位置矢量方程,利用向量封闭投影法解出各回转角间的关系,结合MATLAB软件编程对机构的位置、速度和加速度进行分析。应用ADAMS软件建立机构仿真模型,验证了机构运动学分析的正确性。最后根据机构中回转角的限制条件和结构尺寸关系,分析回转角和结构尺寸对可展开固体反射面机构收拢率的影响,确定2.2m可展开固体反射面机构的回转角和旋转角分别为78°和30°,中心圆盘半径、铰支座一孔纵向尺寸、切换连杆横向尺寸、纵向尺寸分别为245,8,40,18mm,收拢率为0.326,从而为可展开固体反射面机构的设计提供参考。     

可控式增压复合油缸设计及其性能分析

针对大压力、小压力行程的重型液压设备的结构尺寸大、油泵功率大、利用系数低、液压系统复杂等问题,提出一种压力随机可调、工作效率高、结构紧凑、性能稳定可靠的复合式高增压油缸结构。对比分析了复合缸液压机和普通单缸液压机的工作过程;论述了复合缸液压机的运行原理和设计要求;介绍了可控式增压复合油缸性能及应用。结果表明:通过增压缸将液压系统提供的压力油转换为增压油提供给主油缸,使其产生大的压力输出,可有效地减小设备主机尺寸;通过控制缸随时进行高低压转换,各阶段速度压力按需配置,实现成形工艺的最优搭配,成形周期缩短;可以提高油泵的利用系数,减小泵站装机容量;液压系统工作负荷低,性能稳定可靠,寿命长。     

人-椅8自由度车辆系统的平顺性和稳定性研究

文中在Matlab/Simulink中搭建了人-椅8自由度车辆系统仿真模型,在仿真分析时考虑汽车前、后轮之间的延迟性,以路面随机信号作为输入激励,研究了汽车平顺性的时频特性,且分别通过4个轮胎的输入激励研究了汽车的稳定性.研究结果表明:路面输入为随机信号时,车身垂直加速度,车身俯仰角加速度,人-椅垂直加速度,前、后悬架...     

基于FLUENT的液体动静压轴承的动态特性分析

应用计算流体力学软件FLUENT对超高速磨削用五腔动静压轴承进行动态特性研究,得到动静压轴承内部压力场和温度场分布;计算轴承的承载力、温度、刚度、阻尼等动态参数,分析这些动态参数与偏心率以及转速之间的关系。结果表明:在保持供油压力和轴承偏心率不变的情况下,随着转速的提高,油温上升,轴承承载力及偏位角不断增大;在保持供油压力和主轴转速不变的情况下,随着偏心率的增大,轴承流量有所减少,轴承的承载能力不断增大,偏位角基本保持不变。     

电过滤纸喷雾离子源的性能优化及应用研究

常压离子源是质谱技术在生命科学、环境保护、医药卫生、食品安全等领域的研究热点之一.随着质谱分析技术的应用范围越来越广,直接快速分析复杂体系的化合物组成和含量越发重要.本工作基于已研制的小型化离子阱质谱和电过滤纸喷雾离子源,对其分析性能和应用进行深入研究.以提高质谱信号强度和检测灵敏度为目标,对所用滤纸的孔径、离子源尖端...     

Discussion on advanced manufacturing

Advanced manufacturing consists of continuity of manufacturing, its broad sense, and the core of the manufacturing process. The technology of continuous manufacturing is discussed according to both historical and modern perspectives. The relationship between human development and manufacturing technology is also discussed. Manufacturing is a continuously evolving topic. It is not only the foundation and means of imagination, conception, the science, and the technology of material change, but also the expression of national economy, national defense, and the support industries. The broad sense of manufacturing theory, which extends the concept of manufacturing, is an important development in the 20th century. The sense is analyzed in connection with design, material forming theory, synthesis of manufacturing technology, manufacturing modes, life cycle of product, hardware and software, and support environment, etc. At the same time, the core action and the development of the theory and technology of process is also discussed. At the end of this paper, the development directions of mechanical manufacturing science and technology are mentioned.     

Wear mechanism of disc-brake block material for new type of drilling rig

To improve friction and wear performance and service life of the disc-brake pair material of a drilling rig, a new type of asbestos-free frictional material with better performance for disc-brake blocks is developed, and its wear mechanism is investigated by friction and wear experiments. Topography and elementary components of the brake block’s wear surface are analyzed by employing SEM and EDAX patterns, revealing its tribological behaviour and wear mechanism. When the frictional temperature is lower, the surface film of the brake block is thinner, dense, smooth with plasticity, and divided into the mixture area, Fe-abundant area, carbon-abundant area and spalling area. The mixture area consists of various constituents of frictional pairs without ploughing and rolling trace. The Fe-abundant area mainly consists of iron and other constituents. The carbon-abundant area is the zone where graphite and organic fibre are comparatively gathered, while the spalling area is the zone where the surface film is spalled and its surface is rough and uneven, with a loose and denuded state. During the period of high frictional temperature, the frictional surface is also divided into the mixture area, Fe-abundant area and spalling area. In this case, the mixture area consists of abrasive dust from friction pairs, and the surface film is distributed with crumby hard granules, exiguous oxide, carbide granules and sheared slender fibre. The Fe-abundant area is mostly an oxide layer of iron with a flaky distribution. Fracture and spalling traces as well as an overlapping structure of multilayer surface films can be easily found on the surface film. The components of the spalling area are basically the same as that of the matrix. At the beginning of wear, the hard peaks from the friction surface of the disc-brake plough on the surface of the brake block. With increasing frictional temperature, the friction surface begins to soften and expand, and oxidized wear occurs at the same time. During the high-temperature wear period, severely influenced by friction heat, obvious softening and plastic flow can be found on the friction surface of the brake block, its anti-shearing ability is weakened, and adhesive wear is intensified. Thermal decomposition of cohesive material in the brake block is simultaneously strengthened, so that constituents shed due to loss of adhesion. Organic fibre is in a flowing state and obviously generates drawing, shearing, carbonization and oxidization. In addition, thermal cracking, thermal oxidization, carbonization and cyclization of organic substances on the surface of brake block can make the friction surface produce pores or cracks, thus fatigue wear occurs.     

Considerations for the incorporation of measured surfaces in finite element models

This work discusses some of the benefits, techniques, challenges, and considerations associated with the incorporation of measured surfaces in finite element (FE) models including how much surface data to measure and import into the model, the shape of the surface geometry to create, the presence and effect of surface layers and impurities, the required mesh density for rough surfaces, the nature of the element formulations and material properties at small length scales, the differences between measurement and FE coordinate systems, the limitations and idealizations of the FE method, issues associated with boundary conditions and their ability to impose or prevent conformal contact, and issues associated with the size of the pinball region and the contact stiffness relative to the nature of the surface. It also describes some current and future research directions that can be used to validate and expand existing techniques and to improve our understanding of surface phenomena.     

智能垃圾分拣系统的模拟与实现

针对当今世界城市生活垃圾不断增长造成的自然环境污染和资源浪费等问题,对我国和欧美等发达国家的城市生活垃圾分类收集和分类处理方面进行了对比研究,对发达国家在城市生活垃圾处理过程中的安全分类处理方式和垃圾再利用策略进行了归纳,结合国内外垃圾分类处理所遇到的问题和不足,设计制造出了一套实现垃圾桶颜色识别、路线识别、机械手动作和到达指定位置的自动化垃圾分拣系统模型,利用Code Warrior 5.0软件开发平台对系统程序在线调试,通过系统的反复运行对智能分拣小车的自动寻迹进行了累积误差统计试验.研究结果表明,智能垃圾分拣系统的累积误差波动稳定,寻迹的能力比较准确、可靠,实现了垃圾自动分拣的过程,为工业的应用实现提供了有利的参考和理论依据.