1、毕业设计(论文)外文资料翻译院 系专业学生姓名班级学号外文出处Mechanism and Machine Theory附件:1.外文资料翻译译文(约3000汉字); 2.外文资料原文(与课题相关的1万印刷符号左右)。指导教师评语:指导教师签名:年月日Application, Design, and Manufacturing of Conical Involute Gears for Power TransmissionsDr. J. Borner, K. Humm, Dr. F. Joachim, Dr. H. Yakaria,ZF Friedrichshafen AG , 88038Fri
2、edrichshafen, Germany:ABSTRACT Conical involute gears (beveloids) are used in transmissions with intersecting or skew axes and for backlash-free transmissions with parallel axes. Conical gears are spur or helical gears with variable addendum modification ( tooth thickness ) across the face width. Th
3、e gecometry of such gears is generally known, but applications in power transmissions are more or less exceptional. ZF has implemented beveloid gear sets in varioue applications: 4WD gear units for passenger cars, marine transmissions ( mostly used in yachts ), gear boxes for robotics, and indusrtia
4、l drives. The module of these beveloids varies between 0.7 mm and 8 mm in size, and the crossed axes angle varies between 0and 250. These boundary conditions require a deep understanding of the design, manufacturing, and quality assurance of beveloid gears. Flank modifications, which are necessary f
5、or achieving a high load capacity and a low noise emission in the conical gears, can be produced with the continuous generation grinding process. In order to reduce the manufacturing costs, the machine settings as well as the flank deviations caused by the grinding process can be calculated in the d
6、esign phase using a manufacturing simulation. This presentation gives an overview of the development of conical gears for power transmissions: Basic geometry, design of macro and micro geometry, simulation, manufacturing, gear measurement,and testing.1 IntroductionIn transmissions with shafts that a
7、re not arranged parallel to the axis, torque transmission is P ossible by means of various designs such as bevel or crown gears , universal shafts , or conical involute gears (beveloids ). The use of conical involute gears is particularly ideal for small shaft angles ( less than 15), as they offer b
8、enefits with regard to ease of production, design features, and overall input. Conical involute gaars can be used in transmissions with intersecting or overall input. Conical involute gears can be uese in transimissions with intersecting or skew axes or in transmissions with parallel axes for backla
9、sh-free operation. Due to the fact that selection of the cone angle does not depend on the crossed axes angle, pairing is also possible with cylindrical gears. As beveloids can be produced as external and internal gears, a whole matrix of pairing options results and the designer is provided with a h
10、igh degree of flexibility;Table 1.Conical gears are spur or helical gears with variable addendum correction ( tooth thickness ) Across the face width. They can mesh with all gears made with a tool with the same basic rack. The geometry of beveloids is generally known, but they have so far rarele bee
11、n used in power transmissions. Neither the load capacity nor the noise behavior of beveloids has been examined to any great extent in the past. Standards ( such as ISO 6336 for cylindrical gears ), calculation methods, and strength values are not available. Therefore, it was necessary to develop the
12、 calculation method , obtain the load capacity values, and calculate specifications for production and quality assurance. In the last 15 years, ZF has developed various applications with conical gears:Marine transmissions with down-angle output shafts /1, 3/, Fig. 1Steering transmissions /1/Low-back
13、lash planetary gears ( crossed axes angle 13) for robots /2/Transfer gears for commercial vehicles ( dumper)Automatic car transmissions for AWD /4/, Fig. 22 GEAR GEOMETRY2.1 MACRO GEOMETRY To put it simply, a beveloid is a spur gear with continuously changing addendum modification across the face wi
14、dth, as shown in Fig. 3. To accomplish this, the tool is tilted towards the gear axis by the root cone angle? /1/. This result s in the basic gear dimensions:Helix angle, right/left(1) Transverse pressure angle right/left(2) Base circle diameter right/left(3) The differing base circles for the left
15、and right flanks lead to asymmertrical tooth profiles at helical gears, Fig. 3. Manufacturing with a rack- type cutter results in a tooth root cone with root cone angle q. The addendum angle is designed so that tip edge interferences with the mating gear are avoided and a maximally large tooth height results across the face width. Due to the geometric design limits r for undercut and tip formation, the possible face width decreases as the cone angle increase. Sufficiently well-proportioned gearing is possible up to a cone angle of approx.15.2.2 MCRO GEOMETRYThe pairing of two conical gears g
