Double-roller Enveloping Hourglass Worm Research Articles

Thermal Elastohydronamic Lubrication Characteristics of Inclined Double-roller Enveloping Hourglass Worm Drive

To grasp thermal elastohydrodynamic lubrication (TEHL) characteristics of the conjugating tooth-pairs of inclined double-roller enveloping hourglass worm drive in transmission process. The numerical solutions of line contact thermal EHL were obtained based on meshing theory of this worm drive and the theory of EHL. The TEHL line contact numerical solution of this worm drive is solved by using the multigrid method, and the TEHL film pressure and thickness are got at the same time. The effects of roller radius, offset distance, orifice coefficient and inclined angler on the TEHL characteristics and temperature rise are analysed and compared. The results show that with the increase of roller radius, offset distance and inclined angler, the secondary pressure peak decreases and moves to the outlet region, and the oil film thickness decreases accordingly, with increase in orifice coefficient the second pressure peak rises and move toward the inlet, the film thickness increases. The maximum temperature rises of film, worm and worm gear contact surface reduce as the roller radius, orifice coefficient and inclined angler increase, rose as the offset distance increases. It can reduce temperature rise and improve the oil film thickness thought the optimization calculation in the design.

Theory and Experiment Study of Anti-backlash Single-and Double-roller Enveloping Hourglass Worm Gear

Theory and Experiment Study of Anti-backlash Single-and Double-roller Enveloping Hourglass Worm Gear

A comparative investigation of meshing characteristics of anti-backlash single-and double-roller enveloping hourglass worm gears

A comparative investigation of meshing characteristics of anti-backlash single-and double-roller enveloping hourglass worm gears

Finite Element Analysis of Inclined Double-Roller Enveloping Hourglass Worm Gearing Based on Workbench

To further analyze the deformation and stress of inclined double-roller enveloping hourglass worm gearing, based on the research of geometric characteristic analysis of non-parallel double-roller enveloping hourglass worm gearing and solid modeling of non-parallel double-roller enveloping hourglass worm, helical-line of tooth-surface are obtained using software MATLAB, 3-D model of the worm gearing are established using Pro/E. Finally, finite element analysis based on Workbench are carried out in three different meshing positions of worm gearing. The research methods used in this paper has something referential value for the study of the same type of worm gearing.

Dynamic Force Analysis of the Non-Backlash Double-Roller Enveloping Hourglass Worm Drive Based on LS-DYNA

To study the tooth load distribution, the stress,strength and other issues of the non-backlash double-roller enveloping hourglass worm(NDEHW) drive, a innovative method based on finite element method and LS-DYNA software is used to do dynamic force simulation analysis.The results show that the worm gearing has good transmission performance and engagement performance, the strength and stiffness of the worm gearing does meet the design requirements. All of these work will provid a theoretical foundation and practical experience for actual design and manufacture.

Modification design method for an enveloping hourglass worm gear with consideration of machining and misalignment errors

The influences of machining and misalignment errors play a very critical role in the performance of the anti-backlash double-roller enveloping hourglass worm gear(ADEHWG). However, a corresponding efficient method for eliminating or reducing these errors on the tooth profile of the ADEHWG is seldom reported. The gear engagement equation and tooth profile equation for considering six different errors that could arise from the machining and gear misalignment are derived from the theories of differential geometry and gear meshing. Also, the tooth contact analysis(TCA) is used to systematically investigate the influence of the machining and misalignment errors on the contact curves and the tooth profile by means of numerical analysis and three-dimensional solid modeling. The research results show that vertical angular misalignment of the worm wheel(Δβ) has the strongest influences while the tooth angle error(Δα) has the weakest influences on the contact curves and the tooth profile. A novel efficient approach is proposed and used to minimize the effect of the errors in manufacturing by changing the radius of the grinding wheel and the approaching point of contact. The results from the TCA and the experiment demonstrate that this tooth profile design modification method can indeed reduce the machining and misalignment errors. This modification design method is helpful in understanding the manufacturing technology of the ADEHWG.

Manufacturing Technology Study on Non-Backlash Double-Roller Enveloping Hourglass Worm

The processing of worm gear components is quite simple, and manufacturing method is relatively complete, theres no need to make special equipment. But to new energy equipment, research new-type of manufacturing technology is required. On the basis of meshing theory and drawing on manufacture of the planar enveloping as well as the tapper enveloping hourglass worm, a research of manufacture technique about the non-backlash double-roller enveloping hourglass worm drive has conducted on the Y3180E gear-hobbing machines and four-axis four-linkage NC machines. The key pieces have been processed out, and a calibration has been conducted on the single-head worm. All of these work will provid a theoretical foundation and practical experience for the actual manufacture.

Type Test and Performance Analysis of the Non-Backlash Double-Roller Enveloping Hourglass Worm Drive

A transmission experiment platform was built to make an explicit test plan for the non-backlash double-roller enveloping hourglass worm drive reducing device, according to the type test and performance analysis, the noise, temperature, and efficiency of the new worm was obtained under different load and rotational speed. The results show that the non-backlash double-roller enveloping hourglass worm gearing possesses a excellent meshing performance as expected, which can eliminate the backlash, and it indicates that the new drive has achieved the anticipated project objective, eliminated the hysterisis error in transmission, and has the advantages of low noise, high transmission efficiency.

Parametric Study of Meshing Characteristics With Respect to Different Meshing Rollers of the Antibacklash Double-Roller Enveloping Worm Gear

Roller shapes play a very critical role in the performance of antibacklash double-roller enveloping hourglass worm (ADEHW) gears; however, their influence is seldom reported in the literature. Based on the theories of differential geometry and gear meshing, this paper presents generic models of meshing characteristics for ADEHW gears, including both the contact curve and the tooth profile. We present different meshing functions and their derivatives with respect to each drive type and their associated roller shapes. We also compare the effects of contact curve, tooth profile, tooth undercutting, lubrication angle, induced normal curvature, and autorotation angle in order to design the most optimal tooth profile for the ADEHW gear. Finite element analysis was also conducted in order to minimize the contact stresses as a function of the roller type. Our results show that a spherical roller has the smallest value among the three available meshing roller shapes but is the most difficult design to procure. A cylindrical roller, however, incurs the greatest contact stress.

Parameterized Model of Double-Roller Hourglass Worm Based on Pro/E Secondary Development Technology

According to the spatial meshing theory, the relative coordinate systems of non-backlash double-roller enveloping hourglass worm is established, the helix line and tooth surface equation are deduced. According to worm helix line equation, generating model with Pro/E, parametric modeling by Pro/Toolkit which is the secondary development tool belongs to Pro/E, programming relevant software.

Parameter Optimization of the Non-backlash Double-roller Enveloping Hourglass Worm Gearing

Non-backlash double-roller enveloping hourglass worm gearing is a new-type hourglass worm gearing,which can be used in high precision and big load applications domain. To obtain a non-backlash double-roller enveloping hourglass worm gearing with perfect meshing performance,the optimization design of the worm gearing is presented with the contact and lubrication performances of the gearing taken into consideration. By numerical calculation of the tooth contact parameters that includes lubrication angle,induced normal curvature,entrainment velocity and roller rotation angle,the effect factor of the meshing performance are discussed and the value range of design variables is determined. Then,the optimization model of the worm gearing is built,in which the roller rotation angle and comprehensive coefficient of tooth for elastohydrodynamic lubrication condition are taken as optimization objectives,and the lubrication angle,the strength and stiffness of the worm axis and geometric non-interference are considered as constraint conditions. The GA toolbox in the Matlab software is utilized to obtain the optimal solution. A numerical example shows that this method can be used to effectively improve the meshing performance of the non-backlash double-roller enveloping hourglass worm gearing.