External High-Order Multistage Modified Elliptical Helical Gears and Design Procedure of Its Gear Pair

2014 ◽  
Author(s):  
Jiang Han ◽  
Youyu Liu ◽  
Dazhu Li ◽  
Lian Xia
Keyword(s):  
Design Procedure ◽  
Mathematical Expression ◽  
Gear Ratio ◽  
Helical Gear ◽  
High Order ◽  
Curvature Radius ◽  
Gear Pair ◽  
Contact Ratio ◽  
Helical Gears ◽  
Helical Gear Pair

In view of the limited number of the modified segments for high-order and two-stage modified elliptical helical gears, and poor adjustment capacity for gear ratio, the formation mechanism of a high-order multistage modified ellipse was studied, and a unified mathematical expression of the family of ellipses was obtained. Thus, a design procedure for the helical gear pair of the high-order multistage modified ellipse was suggested, and its transmission characteristics were discussed exhaustively. Moreover, some checking methods such as the curvature radius of the pitch curve, convexity, pressure angle, root cutting, and contact ratio were offered. Finally, two design cases, including two-order and three-stage modified elliptical helical gear pair and two-order and four-stage one, were implemented. The cases indicate that a high-order multistage modified elliptical helical gear can be utilized in practice.

External high-order multistage modified elliptical helical gears and design procedure of their gear pairs

2016 ◽  
Vol 230 (16) ◽  
pp. 2929-2939 ◽  
Author(s):  
Jiang Han ◽  
Youyu Liu ◽  
Dazhu Li ◽  
Lian Xia
Keyword(s):  
Design Procedure ◽  
Mathematical Expression ◽  
Helical Gear ◽  
High Order ◽  
Curvature Radius ◽  
Contact Ratio ◽  
Helical Gears ◽  
The Family ◽  
Pitch Curve ◽  
Helical Gear Pair

In view of the limited quantity of modified segments for high-order and two-stage modified elliptical helical gears, and poor adjustment capacity for transmission ratio, the formation mechanism of a high-order multistage modified ellipse was studied, and a unified mathematical expression of the family of ellipses was derived. Thus, a design procedure for the helical gear pairs of the high-order multistage modified ellipse was suggested, and then their transmission characteristics were discussed exhaustively. Moreover, some checking methods such as curvature radius of pitch curve, convexity, pressure angle, undercutting, and contact ratio were offered. Finally, two design cases, including two-order and three-stage modified elliptical helical gear pair and two-order and four-stage one, were implemented. The cases indicate that a high-order multistage modified elliptical helical gear can be utilized in practice.

scholarly journals Experimental Investigation of the Effect of Gear Ratio on the Dynamic Behavior of a Helical Gear Pair.

1996 ◽  
Vol 62 (602) ◽  
pp. 4078-4085
Author(s):  
Haruo HOUJOH ◽  
Shaofeng WANG ◽  
Ryutaro SHINOHARA ◽  
Shigeki MATSUMURA ◽  
Suguru WADA ◽  
...  
Keyword(s):  
Experimental Investigation ◽  
Dynamic Behavior ◽  
Gear Ratio ◽  
Helical Gear ◽  
Gear Pair ◽  
Helical Gear Pair

scholarly journals Time-varying dynamic analysis for a helical gear pair system with three-dimensional motion due to bearing deformation

2020 ◽  
Vol 12 (5) ◽  
pp. 168781402091812
Author(s):  
Ying-Chung Chen
Keyword(s):  
Three Dimensional ◽  
Helix Angle ◽  
Helical Gear ◽  
Dynamic Responses ◽  
Time Varying ◽  
Gear Pair ◽  
Contact Ratio ◽  
Transverse Pressure ◽  
Helical Gear Pair ◽  
Center Distance

The dynamic response of a helical gear pair system is investigated. A new dynamic model for a helical gear pair system, considering three-dimensional motion due to bearing deformation, is proposed. The proposed model considers the helix angle, gear pair center distance, transverse pressure angle, and the contact ratio as time-dependent variables, which are considered as constants in other models. In fact, three-dimensional motion due to bearing deformation will lead to the changes in a series of dynamic responses. The system equations of motion were obtained by applying Lagrange’s equation and the dynamic responses are computed by the fourth-order Runge–Kutta method. The time-varying dynamic displacements, helix angle, gear pair center distance, transverse pressure angle, and the contact ratio are investigated with bearing deformation, different radial bear stiffness, different axial bear stiffness, and gear eccentricity. The results show that, due to the time-varying effect, this new helical gear pair model provides more accurate dynamic responses than those previous models which are considered as constant. In the future, this study can provide some useful information for the time-varying dynamic design of a helical gear pair system.

scholarly journals An Experimental Investigation of Churning Power Losses of a Gearbox

2018 ◽  
Vol 140 (3) ◽  
Author(s):  
J. Polly ◽  
D. Talbot ◽  
A. Kahraman ◽  
A. Singh ◽  
H. Xu
Keyword(s):  
Helical Gear ◽  
Operating Conditions ◽  
Gear Pair ◽  
Power Losses ◽  
Helical Gears ◽  
Gear Mesh ◽  
System A ◽  
Final Drive ◽  
Helical Gear Pair ◽  
Lubrication Conditions

In this study, load-independent (spin) power losses of a gearbox operating under dip-lubrication conditions are investigated experimentally using a final-drive helical gear pair from an automotive transmission as the example system. A dedicated gearbox is developed to operate a single gear or a gear pair under given speed and temperature conditions. A test matrix that consists of sets of tests with: (i) a single spur, helical gears, or disks with no teeth and (ii) helical gear pairs is executed at various temperatures, immersion depths, and pinion positions relative to its mating gear. Power losses from single gear and gear pair at identical operating conditions are compared to quantify the components of the total spin loss in the form of losses due to gear drag, gear mesh pocketing, and bearings and seals.

Vibration-based fault diagnosis of helical gear pair with tooth surface wear considering time-varying friction coefficient under mixed EHL condition

2021 ◽  
pp. 1-16
Author(s):  
Siyu Wang ◽  
Rupeng Zhu
Keyword(s):  
Dynamic Response ◽  
Hydrodynamic Lubrication ◽  
Helical Gear ◽  
Calculation Model ◽  
Tooth Surface ◽  
Time Varying ◽  
Gear Pair ◽  
Surface Wear ◽  
Mesh Stiffness ◽  
Helical Gear Pair

Abstract Based on “slice method”, the improved time-varying mesh stiffness (TVMS) calculation model of helical gear pair with tooth surface wear is proposed, in which the effect of friction force that obtained under mixed elasto-hydrodynamic lubrication (EHL) is considered in the model. Based on the improved TVMS calculation model, the dynamic model of helical gear system is established, then the influence of tooth wear parameters on the dynamic response is studied. The results illustrate that the varying reduction extents of mesh stiffness along tooth profile under tooth surface wear, in addition, the dynamic response in time-domain and frequency-domain present significant decline in amplitude under deteriorating wear condition.

Sign in / Sign up

Export Citation Format

Share Document