Transmission Error Analysis Research Articles

Gear error control and response of electric vehicle transmission gearing based on gear trimming

The lightweight development of electric vehicle motors is a prominent future trend, with the challenge of transmission vibration and noise acting as a key bottleneck that limits the enhancement of power and speed in electric vehicle drive systems. The noise generated by electric vehicle transmissions is primarily associated with the transmission system and gear structure. In line with this, the present study proposes an analysis of transmission error and response mechanisms through gear modifications. The research delves into the analysis of gear deformation and error generation characteristics. It further investigates methods for parametric equation modeling, tooth profile modification, deformation imprint analysis, and vibration response modeling to examine excitation response analysis and noise reduction techniques pertaining to transmission errors. The findings demonstrate that, under 40 % torque, the shaped gear exhibited a maximum reduction in transmission error of 34.2 %, resulting in an overall error improvement of over 5.7 %. Moreover, the maximum error difference after tooth profile and tooth direction shaping exceeded 2 %. The gear-shaping-based electric vehicle transmission showcased favorable economic and technical performance, while its excitation response mechanism provided valuable guidance for mass production. Overall, these results highlight the significance of analyzing transmission errors through gear modifications in achieving lightweight electric vehicle motors. By addressing transmission vibration and noise issues, this research contributes to overcoming limitations and promoting advancements in power and speed within electric vehicle drive systems.

Theoretical analysis of transmission error in rack and pinion systems

Rack and pinion drive systems are widely used in machine tools with long travel distances because the stiffness is independent of the travelled distance, in contrast to other drive systems such as ballscrews. Although the inherent backlash problem of gear systems has been solved by means of utilizing two pinions independently preloaded, the time-varying mesh stiffness causes periodic position differences between the motor encoder and table position, which is known as transmission error, and may lead to vibrations and dynamic load. Few experimental works have analyzed such transmission error, but there are no theoretical approaches in the scientific literature. Therefore, this work aims to first extend previous analytical and approximate equations for mesh stiffness of gearing to rack and pinion systems and validate them with finite element methods. Finally, the effect of geometry variations, such as pressure angle and tooth thickness tolerance, on transmission error is discussed.

Design and dynamic transmission error analysis of a new type of cycloidal-pin reducer with a rotatable output-pin mechanism

A new type of one-stage precision cycloidal-pin reducer is designed and explored in this study. The design innovatively replaces the fixed output-pin mechanism of conventional cycloidal-pin reducers with a rotatable output-pin mechanism, thereby transforming the sliding contact between the output-pin and the output-hole into a rolling contact. This new structural design is found to significantly improve the transmission efficiency of the reducer. To evaluate the dynamic transmission error (DTE) characteristics of the proposed reducer, a general dynamic model of the cycloidal-pin transmission system considering the influences of multi-source error factors on the geometry of the main components is established. The geometric error of the component is determined by taking random values within a given design-tolerance zone. The geometric error distribution introduced using this method can well match the actual machining situation. Finally, the DTEs of the new reducers with three different tolerance designs are analyzed numerically and tested experimentally. The results show that the new reducer with a reasonable tolerance design can achieve high transmission accuracy and has the potential for application in the joints of industrial robots.

전륜 자동변속기 트랜스퍼 기어 소음 저감에 관한 실험적 연구

Transmission transfer gear noise, due to its nature, is generated in the high frequency region and is therefore at a disadvantage to the hearing on the vehicle condition. In this paper, Academic experimental study was investigated on the bench and vehicle. First through the FRF test, fragile part of transmission case was investigated. After stiffness reinforcement on fragile part of case, structure born noise was improved. Second, through the transmission error analysis, micro geometry optimization was carried out. After micro geometry optimization, transfer gear noise was improved about 5dBA. Third, through the investigation and improvement of transfer path system on the vehicle, finally transfer gear noise reached acceptable level.

Research on the Method of Improving the Precision of Parts in Pearl River Delta Gear Enterprises: Analysis of Gear Transmission Error and Tooth Friction Coefficient Based on the Influence of Tooth Surface Roughness

Tooth surface roughness is an important index to evaluate the quality of gear processing, which affects the gear transmission error and tooth friction coefficient and changes the gear dynamics. Based on the fractal theory, the gear error correction model considering time-varying roughness is derived, and the new model of time-varying roughness and gear error is introduced into the Xu model to construct the friction coefficient model accounting for time-varying roughness and gear error, which has great reference value for improving the accuracy of gear error. The research results show that the root mean square value of gear error increases by 45.39% and 101.08% under comparison Ra = 0.8 μm, Ra = 1.6 μm, and R a = 3.2 μm, respectively, and the root mean square value of time-varying friction coefficient increases by 45.74% and 148.18%, respectively, which provides theoretical method support for precision management and quality management of gear processing in machinery enterprises.

Double modification of a rack cutter using a variable pressure angle and modulus

This study modifies the straight edge of the rack cutter into an arc shape by changing the pressure angle. Using a variable modulus, the tooth surface is longitudinally modified along the axial direction of the rack cutter to create a bulge in the rack teeth in the center of the tooth width. This rack cutter with a double-crowned tooth is used to generate a pinion. An unmodified rack cutter is used to generate a gear. An undercutting analysis of the rack cutter is used to determine the undercutting condition for the double-crowned rack cutter and to determine the limits for the parameter. The transmission error for a gear pair is calculating using a tooth contact analysis. For this study, the assembly error for six cases is used to calculate the transmission error for the gear pair and the contact points for the gear pair are placed on a gear tooth. These contact points used to determine the contact for the gear pair. A transmission error analysis of the gear pair for a double-crowned gear gives a parabolic curve for the transmission error. The distribution of the contact points shows that, regardless of assembly errors, the contact points for the gear teeth are along the center of the tooth surface, starting from the top of the tooth, and gradually moving to the flank and away from the heel. The results show that the values for the transmission error for the modified gear pair for the proposed modification of the variable pressure angle and the variable modulus on a traditional rack cutter are small and the transmission error of the assembly errors are almost similar to those for an ideal assembly.

Design and Dynamic Transmission Error Analysis of a New Type of Cycloidal-Pin Reducer with a Rotatable Output-Pin Mechanism

Design and Dynamic Transmission Error Analysis of a New Type of Cycloidal-Pin Reducer with a Rotatable Output-Pin Mechanism

Transmission error analysis of cycloidal pinwheel meshing pair based on rolling–sliding contact

Transmission error analysis of cycloidal pinwheel meshing pair based on rolling–sliding contact

Uneven Load Contact Dynamic Modelling and Transmission Error Analysis of a 2K-V Reducer with Eccentricity Excitation

Uneven Load Contact Dynamic Modelling and Transmission Error Analysis of a 2K-V Reducer with Eccentricity Excitation

Design and evaluation of two-stage planetary gearbox for special-purpose industrial machinery

The gearbox, as a traditional machine that changes the transmission ratio and transfers power safely, stably, quietly and efficiently, is an irreplaceable component in the field of machinery design. The planetary gear train is the most widely used of the traditional gearbox designs. Although scholars have carried out a variety of research on gearboxes, gear failures, noise and other issues are still common. This article presents a study involving the initial macro geometry design, gear flank modification, static and dynamic analysis, and experimental verification of a two-stage planetary gearbox for special-purpose industrial machinery. Compared to traditional static transmission error simulation, this study presents a novel analysis of the gearbox overall dynamic transmission error. In this research, the modal flexibility is also analyzed to determine the possibility of resonance in the gearbox. As a result, the strength of this gear system is guaranteed by macro design. PPTE (noise evaluation index) of each gear pair is greatly improved after flank modification. The efficiency of power transmission system is also improved with the improvement of vibration. The result of final bench test of the prototype is also quite satisfactory. This also verified the correctness of the theoretical simulation method presented in this research.

Analysis of nonlinear local contact deformation of gear pair using multilevel multi-integration method

For the non-conforming contact problem of spur and helical gear pair, the total deformation of gear pair is usually separated into a linear global term and a nonlinear local term. To calculate the local contact deformation, the Hertz solution is widely used while lubrication is ignored. In order to account for the effect of elastohydrodynamic lubrication, the local contact deformation of helical gear pair is calculated on the basis of multilevel multi-integration method in this work. Through comparison with results obtained by analytical method and general numerical integration method, the effectiveness of the presented method is verified and it lays foundation for further analysis of transmission error of gear pair.

Design and Transmission Error Analysis of CBR Reducer

Abstract A new one-stage type cycloid drive reducer named China Bearing Reducer (CBR) is designed and its tooth contact analysis is investigated. First, the CAD model is built in SolidWorks and the structure of CBR reducer is introduced. Its advantages and disadvantages are compared with rotor vector (RV) reducer and harmonic drive reducer. Second, the mathematic model of cycloid profile and modified cycloid profile are established based on gear meshing and differential geometry, and the tooth shapes of three different modifications are compared with CBR25 reducer. Third, the conventional TCA method is described and a new TCA method by using discretized points is proposed to calculate transmission error and contact force of cycloid drive. Both the methods are used to compute the unloaded transmission error of CBR25 reducer to compare the computational efficiency. Finally, three different modified methods of tooth profile are investigated by using the new TCA method to calculate transmission error and contact force of CBR25 reducer, and the results show that the negative isometric and negative offset modified method is best for CBR25 reducer to reduce transmission error and contact force. The prototype of CBR25 reducer is manufactured and the transmission error and hysteresis curve are measured by using a testing bench. The results show that the new TCA method can be used to calculate transmission error and help better design the CBR reducer.

Transmission Error and strain analysis of lightweight gears by using a hybrid FE-analytical gear contact model

Abstract In this paper the transmission error and the strain field are analysed for two gear pairs, with different lightweight designs, reflecting the common industrial practice. The methodology used for the analysis is based on a hybrid FE-Analytical approach implemented in a multibody solver which allows to achieve a good accuracy with a low computational effort. The specific formulation allows to well describe the deformation field of the gear body from which the strain values can be computed at specific locations in the FE model. The numerical method used in this work is validated both in terms of transmission error and strain field, using the results obtained from an experimental campaign performed on a high-precision gear test rig.

建南气田输差分析及防治措施

建南气田输差分析及防治措施

Transmission Error Analysis of a Trochoidal Gear Reducer

Transmission Error Analysis of a Trochoidal Gear Reducer

A perspective on gear meshing quality based on transmission error analysis

Gears are one of the most important elements in power transmission systems. Their use is present in many industries due to their various advantages. Durability, constant transmission ratio, reduced size, high efficiency, suitability for a wide range of powers are some of the benefits. But gears also feature a number of drawbacks like vibration of the gear meshing system generating an undesirable noise. The main source of such a noise is the transmission error that result from misalignment of the gear, tooth profile errors and tooth deflections. This article is a state of the art on the theory of transmission error components that influences gear meshing. The errors of static transmission in gears may have several causes. One originates in the function of the gear mechanism which transmits the rotation and torque between axes and generates forces on the teeth, thus modifying their geometry due to elastic deformation. Another undesirable consequence that would be present even if tooth deflections were insensitive is caused by manufacturing errors such as profile, eccentricity, pitch or even assembling errors. One of the best known methods of reducing transmission error of a gear pair is the profile correction. This paper describes the main differences between static and dynamic transmission errors. It will be shown the most common methods of detecting the transmission error using analytical methodology, optimization algorithms, hybrid numerical/ Finite-Element Analysis and experimental researches in order to establish the dynamic behaviour of the gear pairs under different operating conditions.

Transmission error analysis for heavy-duty gearbox

This paper deals with an analysis of the transmission error. For this purpose, the measuring loop was assembled from two gear boxes. Subsequently, angles, torque and shaft speed were set or measured. For the evaluation a calculation method was used, and the impact of the different transmitted torque was evaluated. The measuring loop enables to test at different operation conditions of torque and shaft rotation direction. In this paper, the static transmission error analysis for braking mode at 50 rpm shaft speed and torque range from 600 to 2400 Nm is described.

Analysis of transmission error and load distribution of a hoist two-stage planetary gear system

The research described in this study is aimed at exploring the transmission characteristics of a two-stage planetary-gear transmission system. Firstly, a novel rigid-flexible coupled dynamic model was established with the consideration of gear clearance, time-varying meshing stiffness, and the deformation of the bearing and shaft. Secondly, based on the novel dynamic model, different profile modification parameters are carried out to optimize the transmission error, load distributions, and harmonic quantity of the transmission system. The analysis results show that dynamic characteristics can be improved by optimizing the multi-stage planetary gear profile. The study provides a valuable reference for the design of multi-stage planetary-gear transmission systems of hoist industry.

Transmission Error Analysis and Disturbance Optimization of Two‐Stage Spur Gear Space Driven Mechanism with Large Inertia Load

For the nonlinear disturbance actual issues of the model space drive mechanism two‐stage spur gear system, a nonlinear dynamic model of 14‐DOF (degree of freedom) two‐stage spur gear with time‐varying stiffness and damping was established. This model has been developed previously by the authors to access the large inertia on the dynamic response of spur gear space driving mechanism, and its effectiveness was proved by a motion simulation experiment. In this paper, the profile error (PE) and the index error (IE) were enhanced in the dynamic model. The effects of profile error, index error, and variable load torque on transmission error (TE) were analyzed, while the optimization was proposed according to the analyzed result. The peak‐to‐peak value of the optimized load transmission error (LTE) was reduced by 60.7%, which improved the transmission accuracy and reduced the phenomenon of disturbance. The research of nonlinear dynamical model of two‐stage spur gear and the TE of the large inertia load were enriched, which provided an important reference for the actual design of the gear system.

二级直齿轮空间驱动机构传动误差分析

二级直齿轮空间驱动机构传动误差分析