十字轴万向联轴器的结构改进_图文

1、十字轴万向联轴器的结构改进董俊华(辽东学院,辽宁丹东118003摘 要:根据国内外十字轴万向联轴器的生产、使用和维修等方面的情况,在分析了十字轴万向联轴器的主要失效形式的基础上,提出了其结构改进的方法。该方法对延长十字轴万向联轴器的使用寿命和结构改进具有一定指导意义和参考价值。关键词:十字轴;联轴器;结构改进中图分类号:T H139 文献标志码:A十字轴万向联轴器又称万向节,适用于连接轴线有一定偏斜、且其相对位置经常变化的两相交轴,以传递运动和转矩。这种联轴器具有传递功率大、结构紧凑等优点,在汽车、拖拉机和轧钢机等传动装置中获得广泛应用,属于机械基础通用部件。由于十字轴万向联轴器是一种空间球面

2、四杆机构,主动轴与从动轴间可在任意方向偏斜 角,通常可达35 45 。在其工作过程中,当主动轴转动1周,从动轴亦相应转动1周,但两轴的瞬时传动比在不断变化,伴随有振动、冲击等附加动载荷,再加上润滑条件不够理想,这些都会引起十字轴万向联轴器活动连接零件间的磨损加剧,使工作状况进一步恶化。因此,十字轴万向联轴器是易损部件,经常成为传动装置中的薄弱环节。作者在分析了十字轴万向联轴器的主要失效形式的基础上,提出了结构改进的方法,以期能延长使用寿命,提高传动效率和改善工作条件。1 十字轴万向联轴器的主要失效形式1作为产品生产的十字轴万向联轴器,若材质、加工和装配工艺符合技术要求,在正常使用条件下,一般很

3、少发生十字轴、节叉等断裂现象,它的失效形式主要有以下几种。1滚针轴承磨损无论是滚针、十字轴轴颈和轴承碗内表面的磨损,都会使轴承间隙增加而产生松晃,至使滚动体之间相互撞击,这不仅会加剧磨损,且产生较大噪声。2十字轴(或轴承碗凹痕凹痕的特征如下:a 凹痕与十字轴轴颈母线倾斜一定角度,约为2 10 ;b 较深的凹痕分布在十字轴轴颈的受力侧面;c 同一凹痕的深浅程度也不一样,在靠近十字轴端部的凹痕较深。3点蚀和剥落无论点蚀和剥落都会增加零件表面粗糙度值,使摩擦阻力上升,还会在摩擦副中混杂金属碎屑,破坏轴承正常工作。4节叉孔磨损和变形由于节叉刚度较差,长期运转后,节叉孔会产生磨损和变形,这样导致节叉孔与

4、轴承碗的配合间隙增加,产生振动和冲击现象。2 十字轴万向联轴器的结构改进为了延长十字轴万向联轴器的使用寿命,提高传动效率,减少噪声和振动,以及便于维修保养等,必须对十字轴万向联轴器的传统结构进行必要的改进,经分析研究,对结构进行改进的主要设想与措施简述如下。2 1 使滚针轴承中的接触应力均匀分布十字轴万向联轴器中最容易损坏的是滚针轴承。无论磨损、凹痕、点蚀和剥落等,都与滚针轴承中的接触应力有关。十字轴轴颈的接触应力呈梯形分布,愈接近十字轴轴端则接触应力愈大,这可从十字轴凹痕深度来证实2。为了减少滚针对十字轴轴颈的接触应力,并趋于均匀分布,可采取如下措施:1 采用锥形结构图1锥形结构如图1a所示

5、,把十字轴轴颈加工成锥形,使滚针在靠近十字轴端部的径向间隙增加,从而使该处的接触应力减小。考虑到将十字轴轴颈加工成锥形较复杂,可以把轴承碗外表面加工成锥形,如图1b所示,53!新技术新工艺机械加工艺与装备 2007年 第10期防止轴承碗装入节叉孔和传递扭矩时产生变形。2在十字轴中做出偏心孔图2带有偏心孔的十字轴传统的十字轴轴颈有直通的油孔,改进后的结构如图2所示,在十字轴中做出偏心孔。各孔的偏心距均为e ,相邻轴颈中孔的偏心方向相反,均偏向于轴颈的受力面。这样,降低了十字轴轴颈受力面的刚度,运转时借助于弹性变形使承载面积增加,从而减少接触应力并趋于均匀分布。此外,将长滚针改成双列滚针或双列滚子

6、,可有效地防止滚针倾斜损坏,使接触应力均匀分布,双列之间可贮存润滑油,有利于改善润滑条件和延长使用寿命。2.2 改善滚针轴承的润滑和密封条件1在十字轴轴颈上开沟槽 十字轴万向联轴器中滚针轴承作有限摆动,沿袭传统结构把十字轴轴颈加工成光滑表面,无法在滚动表面形成完整的油膜。为了改善润滑条件,特地在十字轴轴颈上开出断续的或螺旋形的沟槽,如图3a 、图3b 所示。沟槽的截面形状可经车削或铣削加工成圆弧形,如图3c 所示;也可再经滚压加工成#T 形槽,如图3d 所示。把沟槽间的圆柱面作为滚针的接触表面,而沟槽则用于贮存润滑剂。 2利用弹性密封件在压力下供油图4为利用弹性密封件在压力下供油的2种装置。由

7、于密封件的弹性作用,润滑剂可连续不断地流进摩擦副,图4b 结构尚可利用十字轴转动的离心惯性力作用,增加润滑效果,这种润滑装置无注油孔,润滑剂贮量可供整个使用期应用。2.3 防止十字轴轴向窜动在十字轴万向联轴器高速运转时,由于轴承碗的离心惯性力作用,使十字轴端面与轴承碗底部的间隙增加,引起十字轴轴向窜动。图5 带有弹性盖板的轴承碗为防止上述现象,可在轴承碗上增加轴向压力,以平衡由高转速产生的偏心惯性力,但在转速降低时,轴承碗与十字轴端面因压力过高而磨损严重,轴承温度升高。为此,在轴承碗底部焊上弹性盖板(图5或在十字轴端面与轴承碗间增加端面滚针轴承,以防止十字轴轴向窜动。2.4 增加节叉刚度节叉的

8、变形、磨损与节叉刚度不足有关。为增加节叉刚度,应尽量把节叉孔中心线靠近节叉体(小,增加两叉孔端面的距离H ,选用较小的滚针轴承,如图6所示,经这样改进后,节叉刚度增加50%左右,并减轻了节叉自重。图6增加节叉刚度的改进设计3 结语十字轴万向联轴器的结构改进有多种途径,如使滚针轴承中的接触应力均匀分布,改善滚针轴承的润滑和密封条件,防止十字轴轴向窜动和增加节叉刚度等。文中列举的结构改进措施,旨在拓宽产品改革的思路。而在对传统结构进行实际改革时,尚需根据产品使用要求和生产实际情况进行深入研究。参考文献1陈全明,毛培方.十字轴万向联轴器的失效分析和结构改进J.同济大学学报,1989(2.2长春汽车研

9、究所.万向传动设计J.汽车技术,1971(6.作者简介:董俊华(1972 ,女,硕士学位,讲师,从事机械设计专业研究工作。收稿日期:2007年6月5日责任编辑 周守清54 !新技术新工艺 机械加工艺与装备 2007年 第10期A bstract:The methods and the essenti al techniques of the g roup components database re development of solid edge are i ntroduced. The methods are based on three dimensional CAD software

10、 solid edge,developed by VB and combined with Access database tech nology.It indicates the usability and the serviceability of this data base system.The methods and the essential techniques resort on solving the three dimensional design problems of massive g roup components,standard components,inter

11、changeable parts and are helpful to enhance design efficiency.Key words:three dimensional CAD,solidEdge,g roup components, databaseC ontact A nalysis of Logarithmic S piral Profile C onne ction b ased on A NSY SLIU Gaoling1,ZH ENG Youyi1,W ANG Haiyan2(1.School of M e chanical and Power Engineering,H

12、enan Polytechnic U niversity, Jiaozuo454003,China;2.Jiaozuo U niversity,Jiaozuo454003,Chi naA bstract:T he3D solid model of logarithmic spiral profile connec tion is established by the powerful3D so lid modeling function of CAD software Pro/ENGINEER.T he CA E fini te element software ANSYS is employ

13、ed to the established profile connection model to generate meshes,create contact pair and apply constraints.T hen the contact stress and strain of profile connection is analyzed.T he idea and method are provided for exploiti ng the advantages of spe cialized software and high speed computer in engin

14、eering design. Key words:CAD/CAE,ANSYS,logarithmic spiral profile connec tion,contact analysisLong distance Data A cquisition S ystem D esign Based on M A TLA BCHEN Xiaoyi,LIU Jun'an,WU Chenx i(Department of M echanical Engineering,Hunan Institute of Eng ineering,Xiangtan411101, ChinaA bstract:T

15、 he characters of long distance data acquisition system based on the M atLab are discussed.The design method,principles and realized step are put forward.T he essential technology,the important MatLab built in function are introduced in detail.Key words:data acquisition,long distance communication,M

16、 atLab, MatL ab web serverT urning Machining of Ellipse Base d on Mac ro Program ZHOU Hong1,NING Bin2,ZHOU Wenjun1(1 Hunan Railway Professional Technology College,Zhuzhou412001,China;2 Zhuzhou Electric L ocomotive Co.Ltd,Zhuzhou412001,ChinaA bstract:Macro prog ram is a hand coded form.For the numeri

17、cal control processing,it is quicker and flex ible by macro prog ram than that of by automatic program.T he method and skill for elliptical processing by macro programB is introduced on the CK7150A (FANUC 0iin this paper.Key words:macro program,ellipse,turning machiningT he C haos Ide ntification of

18、 t he C avitation Noise Produce d from W ater JetLIU Ji ang hui,ZHA NG Fenghua,TANG Chuanli n,PEI Jianghong (Hunan Industry University Water Jet Institute,Zhuzhou412008, ChinaA bstract:Water cavitation jet is a potential,high efficient and ener gy sav i ng technology in the field of water disinfecti

19、on.T he core of the technology is the cavitation nozzle.T he cavitation noise sig nals,which were produced from the cavitation nozzles i n different structures,were collected by hydrophone respectively.T he state space of each signal was built by means of Takens T heorem,and its largest Lyapunov exp

20、onent was calculated.T hi s experiment presents a new method for the design and the test of the cavitation nozzle.T he ex periment results displays that the larg est L yapunov exponent of each cavitati on no i se signal is larger than0,which means that these signals are all chaos signals.T he larges

21、t L ya punov ex ponent of the nozzle%is the larg est of the three.This means that the chaos is the fiercest in the state space of the nozzle %,which has a self oscillating cavity,and that the chaos of this noz zle is the most dependent on the initial condition.Key w ords:cavitation,water jet,state s

22、pace,the lyapunov expo nent,nozzleA pplications of Gree n Manufactu ring T e chnology in In d ustr ial Ent erpriseYe Guoji e1,CHEN Cheng feng2,WU Weijie3(1 Guangzhou Otis Elevator Co.,L td,Guangzhou510425,China;2 Xinyu Co.,L td, Guangzhou510425,Chi na;3 Guangdong Vocational College of In dustry&

23、Commerce,Guangzhou510425,ChinaAbstract:T his paper i ntroduces the conception and content of Green Design and Green M anufacturing Technology.And based on the contents of Green Desig n and Green M anufacturing Tech nology,the applications of Green Manufacturing Technology in the industrial enterpris

24、e are discussed in detail.The OTIS elevator is the successful ex ample.Key w ords:green manufacturing,technology,green design,green material,industr i al enter priseStu dy on Pr ofessional Param eter S elf settin g of PID C on trol AlgorithmAbstract:T his article g i ves an example of PID control an

25、d discus ses the intelligent contro l method of self setting of PID parameters which is achieved in computer controlling.It introduces the AI theory in the conventi onal PID controlling self setting of PID pa rameters theory,and firstly expresses the human controlling expe rience as the method of se

26、lf setting of PID parameters.From the expert system aspect,it describes the rule of epsilon production and the in house storag e organization,the establishment of control ling knowledge base as well as the reasoning mechanism.Key w ords:PID controlling,self setting of PID Parameters,expert systemFin

27、ite Elem ent A nalyzing and O ptim al D esign for C oach Body Str uctur e B ased on A NSY STANG Shaohua,LIU Shihao(Nanjing University of Technolog y, Naning210009,ChinaAbstract:T he research backg round of the finite element analyzing and optimal design for coach body structure is described,and the

28、fundamental method and steps of the finite element analyzing for coach body structure are ex pounded in detail.T he3 D model of coach body structure i s established in U G3.0software,then the fi nite element analyzing for coach body structure is carr i ed out in Ansys10.0software,the proposal which

29、can opti mize the coach body structure and increase the load bearing capacity of coach body is put forward by analyzing the compute result.Key w ords:coach body structure,finite element analyzing,optimal design,ANSYSNC Peeling Lathe Based on M otion C ontrol C ardRAN Shengxue1,3,LIU Pinxiao1,2,REN D

30、ezhi1,ZH OU Qinghui4 (1.Henan University of Science and Technology,Luoyang 471009,China; 2.Nanyang Institute of Technology,Nanyang 473004,China;3.N anyang Industr i al School,N anyang473035,Chi na;4.Nanyang SASAC,Nanyang473035,ChinaAbstract:GU GAO GE 400 SG PCI continuous trajectory motion controller can realize multi ax is coordinated motion and high s