scholarly journals Straddle Design of Spiral Bevel and Hypoid Pinions and Gears

1991 ◽  
Vol 113 (4) ◽  
pp. 422-426 ◽  
Author(s):  
F. L. Litvin ◽  
C. Kuan ◽  
J. Kieffer ◽  
R. Bossler ◽  
R. F. Handschuh

The design of spiral bevel and hypoid gears that have a shaft extended from both sides of the cone apex (straddle design) is considered. A main difficulty of such a design is determining the length and diameter of the shaft that might be undercut by the head cutter during gear tooth generation. A method that determines the free space available for the gear shaft is proposed. The approach avoids collision between the shaft being designed and the head cutter during tooth generation. The approach is illustrated with a numerical example.

2011 ◽  
Vol 314-316 ◽  
pp. 384-388
Author(s):  
Xun Cheng Wu ◽  
Jing Tao Han ◽  
Jia Fu Wang

It is an important and fundamental work to establish a general mathematical model for the gear tooth surfaces of spiral bevel and hypoid gears. Based on the three-axis CNC bevel gear machine, a mathematical model with the equations of the radial position vector, the normal unit vector and the second order parameters for the generated gear tooth surfaces of spiral bevel and hypoid gears is established. The mathematical model can be used for the gear tooth surfaces generated in different types on both the three-axis CNC bevel gear machine and the cradle bevel gear machine. As an application example of the mathematical model, the generating motions of the cradle bevel gear machine are determined.


Author(s):  
M. Kolivand ◽  
A. Kahraman

Manufacturing errors typically cause real (measured) spiral bevel and hypoid gear surfaces to deviate from the theoretical ones globally. Tooth surface wear patterns accumulated through the life span of the gear set are typically local deviations that are aggravated especially in case of edge contact conditions. An accurate and practical methodology based on ease-off topography is proposed in this study to perform loaded tooth contact analysis of spiral bevel and hypoid gears having both types of local and global deviations. It starts with definition of the theoretical pinion and gear tooth surfaces from the machine settings and cutter parameters, and constructs the theoretical ease-off and roll angle surfaces to compute unloaded contact analysis. Manufacturing errors and localized surface wear deviations are considered to update the theoretical ease-off to form a new ease-off surface that is used to perform a loaded tooth contact analysis according to the semi-analytical method proposed earlier. At the end, a numerical example with locally deviated surfaces is analyzed to demonstrate the effectiveness of the proposed methodology as well as quantifying the effect of such deviations on load distribution and the loaded motion transmission error.


Author(s):  
Claude Gosselin ◽  
Jack Masseth ◽  
Wei Liang

In the manufacturing of spiral-bevel and hypoid gears, circular cutter dimensions are usually based on the desired performance of a gear set. In large manufacturing operations, where several hundred gear geometries may have been cut over the years, the necessary cutter inventory may become quite large since the cutter diameters will differ from one geometry to another, which results in used storage space and associated costs in purchasing and maintaining the cutter parts. Interchangeability of cutters is therefore of significant interest to reduce cost while maintaining approved tooth geometries. An algorithm is presented which allows the use of a different cutter, either in diameter and/or pressure angle, to obtain the same tooth flank surface topography. A test case is presented to illustrate the usefulness of the method: the OB cutter diameter of an hypoid pinion is changed from 8.9500" to 9.1000". CMM results and the comparison of the bearing patterns before and after change show excellent correlation, and indicate that the new pinion can be used in place of the original pinion without performance or quality problems. Significant cost reductions may be obtained with the application of the method.


Author(s):  
Kaihong Zhou ◽  
Jinyuan Tang ◽  
Tao Zeng

New geometry of generating spiral bevel gear is proposed. The key idea of the new proposed geometry is that the gear tooth surface geometry can be investigated in a developed curved surface based on the planar engagement principle. It is proved that the profile curve on the back of generating cone surface is a conical involute curve. The equations of generated gear tooth surface are achieved by the conical involute curve sweeping along the tooth trace of gear. The obtained equations are explicit and independent of the machine-tool settings. This differs from previous studies. The developed theory is illustrated with numerical examples to compare with the previous method, the comparison approves that the method is possible in this way. The new method indicates that there are new solutions to the design the production of spiral bevel gear.


Author(s):  
Yi-Pei Shih ◽  
Zhang-Hua Fong

Because the contact bearings of spiral bevel and hypoid gears are highly sensitive to tooth flank geometry, it is desirable to reduce the flank deviations caused by machine errors and heat treatment deformation. Several methods already proposed for flank correction are based on the cutter parameters, machine settings, and kinematical flank motion parameters of a cradle-type universal generator, which are modulated according to the measured flank topographic deviations. However, because of the recently developed six-axis Cartesian-type computer numerical control (CNC) hypoid generator, both face-milling and face-hobbing cutting methods can be implemented on the same machine using a corresponding cutter head and NC code. Nevertheless, the machine settings and flank corrections of most commercial Cartesian-type machines are still translated from the virtual cradle-type universal hypoid generator. In contrast, this paper proposes a flank-correction methodology derived directly from the six-axis Cartesian-type CNC hypoid generator in which high-order correction is easily achieved through direct control of the CNC axis motion. The validity of this flank correction method is demonstrated using a numerical example of Oerlikon Spirac face-hobbing hypoid gears made by the proposed Cartesian-type CNC machine.


2017 ◽  
Vol 94 (5-8) ◽  
pp. 2993-3004 ◽  
Author(s):  
Zhen-Shan Gao ◽  
Ju-Bo Li ◽  
Xiao-Zhong Deng ◽  
Jian-Jun Yang ◽  
Fu-Xiao Chen ◽  
...  

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