Computerized design, simulation of meshing and stress analysis of non-generated double circular-arc helical gear drives with different combinations of transverse pressure angle

The two gears of the double circular-arc helical gear is a mesh of a concave/convex combination. Because the curvature is close to each other, the strength also increased and thus, it is often used in heavily-loaded workplaces. The national standard for double circular-arc helical gear (ex., GB12759-91) is based on the size of the gear module to design its tooth profile. This shows that tooth geometric-related designs are quite complicated. If the effect of the different pressure angle parameter is considered, we would be unable to conduct relevant studies for the original standard formula with a double circular-arc helical gear set at a pressure angle of 24°. Firstly, this paper would redefine a new double circular-arc helical gear according to the discontinuousness tooth profile molded line of the double circular-arc helical gear and unchangeable pressure angle and explain the improvements in the design and stress analysis of the tooth especially since the double circular-arc helical gear has no limitation in the minimum number of teeth. Thus, the decrease in the driving gears’ number of module and can further increase the reduction gear ratio. For heavily-loaded planetary gear reducer, it’s quite obvious in the miniaturizing and high torque superiority. This paper also used certain winch’s speed reducer as example to explain that the change of the pressure angle can reduce contact stress by 3%~40% and also enhances the torque ability by 3%~40%.

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Geometric design, meshing simulation, and stress analysis of pure rolling cylindrical helical gear drives

Proceedings of the Institution of Mechanical Engineers Part C Journal of Mechanical Engineering Science ◽

10.1177/0954406220912265 ◽

2020 ◽

Vol 234 (15) ◽

pp. 3102-3115 ◽

Cited By ~ 1

Author(s):

Zhen Chen ◽

Ming Zeng ◽

Alfonso Fuentes-Aznar

Keyword(s):

Mechanical Behavior ◽

Stress Analysis ◽

Helical Gear ◽

Design Parameters ◽

Basic Design ◽

Helical Gears ◽

Contact Patterns ◽

Pure Rolling ◽

Tooth Surfaces ◽

Gear Drives

The geometric design, meshing performance, and mechanical behavior of pure rolling helical gear drives are presented. Parametric equations for contact curves on the pinion and gear are determined by coordinate transformation of the active designed pure rolling meshing line for the whole cycle of meshing. Moreover, parametric equations for the tooth surfaces of helical gears with convex-to-convex meshing type are derived according to the motion of generatrices in the transverse section along the calculated contact curves. Then, the basic design parameters are analyzed and formulas for calculation of the geometric size are given. The meshing performance and mechanical behavior, including contact patterns, loaded function of transmission errors, and variation of stresses for two pitch angles of meshing are compared with those of a reference design of micro-geometry modified involute helical gears. Besides, the influence of basic design parameters on tooth contact analysis and stress analysis is studied. The analysis of the results shows that the proposed pure rolling helical gears have the advantage of reducing the relative sliding between tooth surfaces and the possibility of designing pure rolling helical gears with a small number of teeth, though the contact strength of the surfaces is impaired. However, if the appropriate design parameters and Hermite curve parameters for the fillets are properly evaluated as proposed here, the mechanical behavior of the proposed pure rolling helical gear drive, in terms of contact patterns and variation of bending stresses can be superior to that of the micro-geometry modified involute helical gear drives.

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Analysis of axial force of double circular arc helical gear hydraulic pump and design of its balancing device

Journal of Central South University ◽

10.1007/s11771-021-4612-2 ◽

2021 ◽

Vol 28 (2) ◽

pp. 418-428

Author(s):

Yi-fei Wu ◽

Pei-qi Ge ◽

Wen-bo Bi

Keyword(s):

Axial Force ◽

Helical Gear ◽

Hydraulic Pump ◽

Circular Arc

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Geometry Design and Contact Ratio Analysis for Circular Arc Parallel-Axis Helical Gears

Volume 11: Systems, Design, and Complexity ◽

10.1115/imece2016-65820 ◽

2016 ◽

Cited By ~ 1

Author(s):

Z. Chen ◽

B. Lei ◽

Q. Zhao

Keyword(s):

Rolling Process ◽

Helical Gear ◽

Space Curve ◽

Impact Factors ◽

Contact Ratio ◽

Circular Arc ◽

Practical Applications ◽

Geometry Design ◽

Gear Mechanism ◽

The Impact

Based on space curve meshing theory, in this paper, we present a novel geometric design of a circular arc helical gear mechanism for parallel transmission with convex-concave circular arc profiles. The parameter equations describing the contact curves for both the driving gear and the driven gear were deduced from the space curve meshing equations, and parameter equations for calculating the convex-concave circular arc profiles were established both for internal meshing and external meshing. Furthermore, a formula for the contact ratio was deduced, and the impact factors influencing the contact ratio are discussed. Using the deduced equations, several numerical examples were considered to validate the contact ratio equation. The circular arc helical gear mechanism investigated in this study showed a high gear transmission performance when considering practical applications, such as a pure rolling process, a high contact ratio, and a large comprehensive strength.

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Improving the Characteristics of Gear Pumps: Part A — Discharge

Volume 4: 9th International Power Transmission and Gearing Conference, Parts A and B ◽

10.1115/detc2003/ptg-48119 ◽

2003 ◽

Author(s):

Ahmed M. M. El-Bahloul ◽

Yasser Z. R. Ali

Keyword(s):

Correction Factor ◽

Helix Angle ◽

Tooth Profile ◽

Radius Of Curvature ◽

Circular Arc ◽

Pressure Angle ◽

Face Width ◽

Angle Change ◽

Number Of Teeth ◽

Gear Pumps

The main objective of this paper is to study the effect of gear geometry on the discharge of gear pumps. We have used gears of circular-arc tooth profile as gear pumps and have compared between these types of gearing and spur, helical gear pumps according to discharge. The chosen module change from 2 to 16 mm, number of teeth change from 8 to 20 teeth, pressure angle change from 10 to 30 deg, face width change from 20 to 120 mm, correction factor change from −1 to 1, helix angle change from 5 to 30 deg, and radii of curvature equal 1.4, 1.5, 2, 2.5, 2.75, and 3m are considered. The authors deduced that the tooth rack profile with radius of curvature equal 2.5, 2.75, 3m for all addendum circular arc tooth and convex-concave tooth profile, and derived equations representing the tooth profile, and calculated the points of intersections between curves of tooth profile. We drive the formulas for the volume of oil between adjacent teeth. Computer program has been prepared to calculate the discharge from the derived formulae with all variables for different types of gear pumps. Curves showing the change of discharge with module, number of teeth, pressure angle, face width, correction factor, helix angle, and radius of curvature are presented. The results show that: 1) The discharge increases with increasing module, number of teeth, positive correction factor, face width and radius of curvature of the tooth. 2) The discharge increases with increasing pressure angle to a certain value and then decreases with increasing pressure angle. 3) The discharge decreases with increasing helix angle. 4) The convex-concave circular-arc gears gives discharge higher than that of alla ddendum circular arc, spur, and helical gear pumps respectively. 5) A curve fitting of the results are done and the following formulae derived for the discharge of involute and circular arc gear pumps respectively: Q=A1bm2z0.895e0.065xe0.0033αe−0.0079βQ=A2bm2z0.91ρ10.669e−0.0047β

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