Papers by Keyword: Hypoid Gear

Abstract: To achieve the effect of anti-fatigue manufacturing for hypoid gear, the author put forward a new type cold rotary forging technology, the method simplifies the die structure and adopts the local line contact continuous plastic forming. Based on the basic theory of elastic-plastic finite element method (FEM),the author uses ABAQUS to carry out numerical simulation of cold rotary forging and discuss how to build finite element geometric model and grid it in detail, and analyse the definition of workpiece material model in ABAQUS and the merger technology of Abaqus / Explicit and Abaqus / Standard. In order to measure springback error accurately, the alveolar surface shap after springback was got through the technology of surface reconstruction, it was put into Geomagic Qualify software and compare with target CAD model,then the springback error can befully assessed through comparing results.The examles proof that ABAQUS can simulate the deformation and springback process accurately, springback error of cold rotary forging can not be ignored,so springback error must be compensated.

Abstract: The assembly misalignment is the key factor that influences the meshing performance of gear, the meshing performance worked on no-load or light load conditions is more completely expressed by contact pattern and transmission error. According to the contact pattern and transmission error, the influence of assembly misalignment to the meshing performance of hypoid gear is studied, this method break the limitations relying on experience to adjust the installation. Based on the machining principle and method of Gleason hypoid gears which machined by the HGT method, the mathematical model of machining was established, and the theoretical tooth surface equations were derived, on this basis, the hypoid gear as an example, the tooth contact analysis (TCA) was carried out considering assembly misalignment, the conclusion was drew that the influence to the position of tooth surface contact area and the magnitude of transmission errors are different when the Assembly misalignment affecting alone. This can offer certain reference for the installation and adjustment of hypoid gear pair in engineering practice.

Abstract: For hypoid gear which processed by HFT (hypoid gear formate tilt) method, geometry parameters and machining parameters of hypoid gear were calculated by using Gleason card. According to the actual machining process and meshing principle, tooth surface equation was derived by coordinate transformation. Then the discrete coordinates points of tooth surface were obtained by using MATLAB tools and projection transformation principle, and data were saved in ibl format. At last the 3-demensional model of hypoid gear were established by importing the ibl format data in Pro/e.

Abstract: In this paper, it introduces a new method about calculating geometric parameters of hypoid gear. After changing the geometric parameter calculation method made by Gleason company, we can expand 16 solving equations to 20 equations, through establishing three layers of iterative solution conceptions and applying the optimal computation of modern design theory to solve all the geometric parameters, which not only solve the problem about the Gleason method without considering the changing parameters, but also improve the accuracy of the parameters and the stability of the iterative process. Finally, these also lay a foundation for the parametric design of hypoid gear.

Abstract: Improving accuracy ofthe gear tooth surface has become an important challenge, because the toothsurface accuracy greatly influences vibration of gears. However, for the spiralbevel gear, the tooth surface accuracy is considered to be very difficult toevaluate because the geometrical theory is difficult. Generally, the managementof tooth surface accuracy has conventionally been substituted by the toothsurface contact evaluation with red lead, which is a kind of paint. However,the results of visual examinations are too subjective. We therefore focused onthe infrared ray imagery to investigate the gear tooth meshing. In this research,a high response infrared thermography was used to estimate the tooth contact ofa hypoid gear under running conditions. Specifically, we looked at the increasein temperature on the tooth surface caused by gear meshing. The results clearlyshowed that the temperature was affected by load, sliding speed between toothsurfaces, and the average peripheral speed of tooth surface. We also proposedan equation that predicts tooth surface temperature rise and showed its utility.Thus, the proposed method effectively evaluates the tooth surface accuracy ofhypoid gear.

Abstract: The geometry of the tooth surface is important for tooth contact analysis, load tooth contact analysis and the ease-off of gear pairs. This paper presents a mathematical model for the determination of the tooth geometry of Klingelnberg face-hobbed hypoid gears. The formulation for the generation of gear and pinion tooth surfaces and the equations for the tooth surface coordinates are provided in the paper. The surface coordinates and normal vectors are calculated and tooth surfaces and 3D tooth geometries of gear and pinion are obtained. This method may also applied to other face-hobbing gears.

Abstract: By analyzing the characteristics and forming technology of hypoid driving gear, it was suitable for adopting fully enclosed die forging principle to form the gear. Based on different forging methods, three kinds of blank shape and corresponding forming schemes were designed. The three dimensional models of blank and die were created by the UG software. The three forming schemes were simulated by the Deform-3D software. The simulation results of distribution of equivalent stress, distribution of equivalent strain and load-stroke curve were comparatively analyzed. Then the most reasonable scheme was chosen. At last, the rationality of numerical simulation can be further verified by the optimized scheme was proved by experiment.

Abstract: Prediction of the forces in milling hypoid gear was often needed in order to establish automation and optimization of the tooth-milling processes. Based on the geometrical theory of the format face-milling, the multi-toothed milling forces theoretical model for form milling the gear of the hypoid gears is presented, the milling force factors were calibrated via single factor experiments and the simulation programs were prepared. Experiments were carried out to verify the availability of the multi-toothed dynamic milling force model, the experimental results is consistent with the simulation results.

Abstract: Design and manufacturing of spiral bevel and hypoid gears is highly complicated and has to be based on the employment of computerized tools. This paper comprehensively describes the latest developments in computerized modeling of tooth surface generation, flank form error correction, ease-off calculation, and tooth contact analysis for spiral bevel and hypoid gears. Accordingly, advanced software programs for computerized design and manufacturing of hypoid gears are developed.

Abstract: At the FZG (Gear Research Centre, Munich, Germany) a research project was carried out to analyze the influence of the hypoid offset on the load capacity of bevel gears by systematic theoretical and experimental investigations. For the experimental investigations two types of bevel gears were designed, one for the pitting tests and one for the tooth root tests. The results of the tooth root tests showed as expected an increasing load capacity with higher offsets. In contrast the pitting tests showed an increasing, but after reaching a maximum, a decreasing load capacity with higher offsets. Regarding the test results a new calculation method was developed that is based on a loaded tooth contact analysis (LTCA). The method is able to consider the local stresses on the flank and in the tooth root. The local strength values are derived out of the standard ISO 6336 for the calculation of helical gears. For bending the local geometry of the tooth root is considered to adopt the strength values of helical gears to bevel and hypoid gears. As a result the local safety factors might be calculated along the face width of pinion and wheel. For pitting the local sliding conditions are taken into account in order to appraise the local lubrication conditions as well as the risk of crack initiations due to shear stresses and higher contact temperatures. The recalculation of the test showed for both types of failure a good correlation between the test results and the calculated values.