scholarly journals Modification Method of Tooth Profile of Locomotive Traction Gear Based on Rodent Arm Variation

2019 ◽  
Vol 48 (1) ◽  
pp. 89-97
Author(s):  
Lei Lei ◽  
Haichun Ding ◽  
Liang Xuan ◽  
Meichao Qin ◽  
Siyuan Tian ◽  
...  

Locomotive traction gear is the key component to power transmission and speed control in locomotive transmission system, which plays an important role in locomotive running speed and load-carrying torque. Considering that there is not universal rule for the method of modification of locomotive gear at present, in this paper, the tooth profile modification is considered with the combination of the increased contact ratio and the variation of the moment arm of action. Based on the principle of modification, according to the load direction after modification, the change rule of moment arm of action after modification is determined, and the interval range of tooth profile modification is also determined. Taking a certain locomotive traction gear as an example, the results obtained through the method of modification which based on combining moment arm of action variation with the increase of contact ratio and the method based on the traditional empirical formula are compared through finite element simulation respectively, on this account to verify the superiority of the theory of modification, which has important theoretical significance for profile modification of locomotive traction gear.

Author(s):  
Jiande Wang ◽  
Ian Howard

Compared to the commonly used Low Contact Ratio Spur Gears (LCRG), High Contact Ratio Spur Gears (HCRG) can provide higher power to weight ratio, and can also achieve smoother running with lower Transmission Error (TE) variations. To achieve the benefits of High Contact Ratio Spur Gears (HCRG), its tolerance to manufacturing errors and elastic deformation has to be increased. After various attempts by previous researchers, double scope tooth profile modifications have been seen as being of major interest showing great potential for improvements in most applications. Research presented in this paper concentrated on providing further proofs and verifications on the topic by using modern numerical methods and comprehensive analysis. Additionally, a general Bulk Tooth Rotation (BTR) type tooth profile modification is introduced and applied to the High Contact Ratio Spur Gears (HCRG) in order to improve the tooth profile design and some common higher order analysis is shown allowing further comments to be made.


Author(s):  
Hsiang H. Lin ◽  
Jing Liu

A computer simulation was conducted to investigate the effectiveness of profile modification for reducing dynamic loads in high-contact-ratio gears with different tooth spacing errors. The simulation examined varying amplitudes of spacing error and differences in the span of teeth over which the error occurs. The modification considered included both linear and parabolic tip relief. The dynamic analysis was performed using a revised version of a NASA gear dynamics code, modified to take into consideration the tooth spacing errors in the dynamic analysis. The findings of this study can be used to design robust tooth profile modification for improving dynamic performance of high-contact-ratio gear sets with different tooth spacing errors.


1993 ◽  
Vol 115 (1) ◽  
pp. 171-178 ◽  
Author(s):  
Hsiang Hsi Lin ◽  
Chinwai Lee ◽  
F. B. Oswald ◽  
D. P. Townsend

This paper presents a numerical procedure for minimizing dynamic effects on high-contact-ratio gears by modification of the tooth profile. The paper examines and compares both linear and parabolic tooth profile modifications of high-contact-ratio gears under various loading conditions. The effects of the total amount of modification and the length of the modification zone were systematically studied at various loads and speeds to find the optimum profile design for minimizing the dynamic load and the tooth bending stress. Parabolic profile modification is preferred over linear profile modification for high-contact-ratio gears because of its lower sensitivity to manufacturing errors. For parabolic modification a greater amount of modification at the tooth tip and a longer modification zone are required. Design charts are presented for high-contact-ratio gears with various profile modifications operating under a range of loads. A procedure is illustrated for using the charts to find the optimum profile design.


2018 ◽  
Vol 777 ◽  
pp. 569-574
Author(s):  
Zhong You Xie

Due to thin skins and soft core, it is apt to local indentation inducing the concurrence of geometrical and material nonlinearity in sandwich structures. In the paper, finite element simulation is used to investigate the bending behavior of lightweight sandwich beams under large deflection. A modified formulation for the moment at mid-span section of sandwich beams under large deflection is presented, and energy absorption performance is assessed based on energy absorption efficiency. In addition, it is found that no local indentation arises initially, while later that increases gradually with loading displacement increasing. The height of the mid-span section as well as load-carrying capacity decreases significantly with local indentation depth increasing.


Sign in / Sign up

Export Citation Format

Share Document