scholarly journals Design of Electrically Powered Morphing Winglet

2021 ◽  
Author(s):  
Kunj Mistry
Keyword(s):  
Material Selection ◽  
Gear Tooth ◽  
Planetary Gear ◽  
Gear Ratio ◽  
Stepper Motor ◽  
Spur Gears ◽  
Input Shaft ◽  
Gear Drive ◽  
Electrical Actuator ◽  
Gear Drives

Cycloidal and planetary gear drives are considered for the actuation of an electrically powered morphing winglet. A torque of 6723 N*m is required at the winglet hinge. The stepper motor selected as the electrical actuator is the HT34-487 stepper motor. This motor can provide a torque of approximately 6 N*m. The cycloidal drive consists of the selected stepper motor, a bevel gearbox, and a two-stage cycloidal gearbox. The bevel gearbox is used to change the axis of rotation of the stepper motor from span-wise direction to chord-wise direction. Stage one of the cycloidal gearbox contains an input shaft, two cycloidal disks with 180 degrees offset rotation, an eccentric cam and an output shaft. The cycloidal disks in stage one have 35 lobes, providing a gear ratio of 35:1. The second stage of the cycloidal gearbox consists of only one cycloidal disk with 34 lobes, providing a gear ratio of 34:1. The total gear ratio of the cycloidal drive is 1190:1. Material selection and FEA simulations are performed on the components in the cycloidal drive to ensure the selected materials can withstand the applied loads. A differential planetary gear drive is also considered to actuate an electrically powered morphing winglet. Spur gears are selected to be used as the sun and planet gears. A ratio of 180:1 is achieved in the planetary gear drive. Using gear tooth bending calculators, it is found that designing spur gears to withstand the loads of the electrically powered morphing winglet and to fit inside the dimensions of the wingbox is not feasible.

scholarly journals Design of Electrically Powered Morphing Winglet

2021 ◽  
Author(s):  
Kunj Mistry
Keyword(s):  
Material Selection ◽  
Gear Tooth ◽  
Planetary Gear ◽  
Gear Ratio ◽  
Stepper Motor ◽  
Spur Gears ◽  
Input Shaft ◽  
Gear Drive ◽  
Electrical Actuator ◽  
Gear Drives

Cycloidal and planetary gear drives are considered for the actuation of an electrically powered morphing winglet. A torque of 6723 N*m is required at the winglet hinge. The stepper motor selected as the electrical actuator is the HT34-487 stepper motor. This motor can provide a torque of approximately 6 N*m. The cycloidal drive consists of the selected stepper motor, a bevel gearbox, and a two-stage cycloidal gearbox. The bevel gearbox is used to change the axis of rotation of the stepper motor from span-wise direction to chord-wise direction. Stage one of the cycloidal gearbox contains an input shaft, two cycloidal disks with 180 degrees offset rotation, an eccentric cam and an output shaft. The cycloidal disks in stage one have 35 lobes, providing a gear ratio of 35:1. The second stage of the cycloidal gearbox consists of only one cycloidal disk with 34 lobes, providing a gear ratio of 34:1. The total gear ratio of the cycloidal drive is 1190:1. Material selection and FEA simulations are performed on the components in the cycloidal drive to ensure the selected materials can withstand the applied loads. A differential planetary gear drive is also considered to actuate an electrically powered morphing winglet. Spur gears are selected to be used as the sun and planet gears. A ratio of 180:1 is achieved in the planetary gear drive. Using gear tooth bending calculators, it is found that designing spur gears to withstand the loads of the electrically powered morphing winglet and to fit inside the dimensions of the wingbox is not feasible.

Determination of Addendum Modification Coefficients for Spur Gears Operating at Non-Standard Center Distances

2003 ◽  
Author(s):  
M. A. Sahir Arikan
Keyword(s):  
Gear Tooth ◽  
Gear Ratio ◽  
Spur Gears ◽  
Contact Ratio ◽  
Performance Variables ◽  
Practical Design ◽  
Gear Drives ◽  
Maximum Contact ◽  
Center Distance

Although it is possible to find some recommended conventional values both for the sum of the addendum modification coefficients and for the allocation of the sum of the addendum modification coefficients (e.g. ISO/TR 4467), a detailed analysis is necessary to determine the addendum modification coefficient values for the desired optimization criteria and the performance since the main objective of the above mentioned sources is to facilitate practical design of non-standard gear drives which will not have problems while operating. They give practical average values within a safe range. In this study, by considering the required gear ratio, center distance and the desired backlash, alternative gear pairs are determined and corresponding gear performance variables are calculated in order to allocate the addendum modification coefficients for the pinion and the gear by using criteria such as: not having undercut or pointed (or excessively-thinned-tip) tooth, having desired proportions for the lengths of the dedendum and addendum portions of the line of action, having maximum contact ratio, having sufficient bottom clearance, having minimum contact stresses, having balanced pinion and gear tooth root stresses, having equal pinion and gear lives, etc.

Computerized Design, Generation and Simulation of Meshing and Contact of Modified Flender Worm-Gear Drives

1996 ◽  
Author(s):  
I. H. Seol ◽  
Faydor L. Litvin
Keyword(s):  
Gear Tooth ◽  
Worm Gear ◽  
Numerical Examples ◽  
Transmission Errors ◽  
Gear Drive ◽  
Bearing Contact ◽  
Tooth Surfaces ◽  
Design Generation ◽  
Computerized Simulation ◽  
Gear Drives

Abstract The worm and worm-gear tooth surfaces of existing design of Flender gear drive are in line contact at every instant and the gear drive is very sensitive to misalignment. Errors of alignment cause the shift of the bearing contact and transmission errors. The authors propose : (1) Methods for computerized simulation of meshing and contact of misaligned worm-gear drives of existing design (2) Methods of modification of geometry of worm-gear drives that enable to localize and stabilize the bearing contact and reduce the sensitivity of drives to misalignment (3) Methods for computerized simulation of meshing and contact of worm-gear drives with modified geometry The proposed approach was applied as well for the involute (David Brown) and Klingelnberg type of worm-gear drives. Numerical examples that illustrate the developed theory are provided.

A Multi-Purpose Planetary Gear Testing Machine for Studies of Gear Drive Dynamics, Efficiency, and Lubrication

1973 ◽  
Vol 95 (4) ◽  
pp. 1123-1130 ◽  
Author(s):  
R. Kasuba ◽  
E. I. Radzimovsky
Keyword(s):  
Gear Tooth ◽  
Measurement Techniques ◽  
Testing Machine ◽  
Planetary Gear ◽  
Gear Drive ◽  
Operational Characteristics ◽  
Surface Durability ◽  
Drive Dynamics ◽  
Selection Of

Feasibility of a multi-purpose testing machine for research studies in gearing has been demonstrated with construction of a unique gear testing machine with a differential planetary gear drive. This machine was used in such interdependent studies as determination of instantaneous gear tooth engagement loads, minimum film thicknesses, and gear efficiencies. With minimal structural and mechanical modifications, this gear research machine can be used for studies of surface durability, thermal distribution in gear meshing zones, and effects of variable torques and torsional oscillations on performance of gearing. Most of these studies could be conducted simultaneously. Upon selection of appropriate gear ratios, this machine was operated either with one or two stationary gears. Presence of stationary gears simplified greatly the measurement techniques and increased the reliability of tests. This machine can accommodate spur, helical or any special type of gearing. Design and operational characteristics of this machine, as well as a short summary of research projects performed on this machine, are presented in this paper.

STUDY OF WEAR RESISTANCE OF REINFORCED POLYAMIDE COMPOSITES FOR METAL-POLYMER GEAR DRIVES

Tribologia ◽  
2018 ◽  
Vol 279 (3) ◽  
pp. 19-23
Author(s):  
Myron CHERNETS ◽  
Serge SHIL'KO ◽  
Mikhail PASHECHKO
Keyword(s):  
Wear Resistance ◽  
Sliding Friction ◽  
Gear Wheel ◽  
Gear Ratio ◽  
Carbon Fibres ◽  
Gear Drive ◽  
Glass Fibres ◽  
Gear Drives ◽  
Contact Pressures ◽  
Metal Polymer

An experimental study of the wear resistance of two dispersion-filled composite materials based on polyamide used in metal-polymer gear drives with a 30% volume content of short glass or carbon fibres was performed according to the technique proposed by the authors. As a result of tribotests in the “pin-disk” scheme, the mass wear of these composites was determined under dry friction conditions for steel 45 at room temperature in the range of contact pressures of 10–40 MPa, as well as the kinetics of the coefficient of sliding friction and the contact temperature of the tribosystem elements. It was established that polyamide strengthened by carbon fibres has almost four times higher wear resistance in comparison with a polyamide filled with glass fibres. The wear resistance characteristics that are the basic parameters of the tribokinetic wear model are calculated, using the durability of the straight spur metal-polymer gear drive on the basis of the original calculation method. It was established that gear drive durability with a pinion or a wheel reinforced with carbon fibres is more than eight times the durability of gear drive with gear wheels from polyamide filled with glass fibres. The gear drive durability with the steel pinion and the composite gear wheel increases in proportion to the gear ratio as compared to the gear drive with the composite pinion and the steel wheel. The change in the maximum contact pressures in the mesh interval was calculated.

Manufacturing of Cycloid Tooth Profile for RV and Cyclo Drives by Threaded Wheel Hobbing and Grinding

2019 ◽  
Vol 825 ◽  
pp. 106-113
Author(s):  
Ling Chiao Chang ◽  
S.J. Tsai ◽  
Jia Sheng Wei ◽  
Pin Ching Chen
Keyword(s):  
Planetary Gear ◽  
Gear Ratio ◽  
Tooth Profile ◽  
Grinding Wheel ◽  
Axial Section ◽  
Precision Motion ◽  
Gear Drives ◽  
Synthesis Approach

Cycloid planetary gear drives are widely used in power and precision motion transmission because of high gear-ratio and good shock absorbability. The aim of the paper is to propose a synthesis approach to generate necessary profiles for manufacturing with thread-wheel type tools based on a given cycloid tooth profile. Two different cases are illustrated in the paper to calculate these profiles, the profiles of thread wheel on normal or axial section, the equivalent rack profile, as well as the profile of dressing or grinding wheel for grinding or hobbing.

Gear Transmission Density Maximization

2011 ◽  
Author(s):  
Alexander L. Kapelevich ◽  
Viacheslav M. Ananiev
Keyword(s):  
Gear Tooth ◽  
Load Capacity ◽  
Gear Ratio ◽  
Gear Transmission ◽  
Gear Trains ◽  
Reduced Costs ◽  
Gear Drives ◽  
Internal Gear ◽  
Ratio Optimization ◽  
Volume Functions

Maximization of the gear transmission density presents an important task. It allows to increase the output torque within given dimensional constrains that is critical, for instance, in racing gearboxes, or to reduce size and weight of aerospace gear drives. It can also lead to reduced costs for automotive and consumer product gear trains, etc. There are several ways to increase gear drive load capacity, including advanced design, materials, and technologies. This paper presents an approach that allows optimizing gearbox kinematic arrangement and gear tooth geometry to achieve high gear transmission density. It introduces dimensionless gearbox volume functions, which can be minimized by the internal gear ratio optimization. Different gearbox arrangements are analyzed to define a minimum of the volume functions. Application of the asymmetric gear tooth profiles power density maximization is also considered.

Performance simulations of engine-gearbox combinations for lightweight passenger cars

2001 ◽  
Vol 215 (2) ◽  
pp. 259-271 ◽  
Author(s):  
P Soltic ◽  
L Guzzella
Keyword(s):  
Fuel Consumption ◽  
High Speed ◽  
Gear Ratio ◽  
Published Data ◽  
Passenger Cars ◽  
Gear Drive ◽  
Different Types ◽  
Variable Transmission ◽  
Low Efficiency ◽  
Gear Drives

This paper compares the fuel consumption of lightweight passenger cars with three different types of engine (one low speed and one high speed naturally aspirated spark ignited, one turbo-charged compression ignited) and two different types of transmission [continuously variable transmission (CVT) and automated gear drive]. All fuel consumption results are obtained using a quasi-static driving cycle simulator. The implemented models are described in detail. The engines are represented through their eficiency maps, which are obtained by scaling published data. Effciency of the transmission (CVT or gear drive) is modelled in dependence on speed, torque and gear ratio. The simulations show that low fuel consumption can be achieved with all those concepts. CVTs show similar results to automated gear drives. The CVT's theoretical advantage of operating the engine at its most fuel-efficient points is compensated by the relatively low efficiency.

A Method for the Preliminary Geometric Design of Gear Tooth Profiles With Small Sliding Coefficients

2010 ◽  
Vol 132 (5) ◽  
Author(s):  
Jian Wang ◽  
Shanming Luo ◽  
Yue Wu
Keyword(s):  
Gear Tooth ◽  
Design Procedure ◽  
Geometric Design ◽  
Machining Process ◽  
Manufacturing Method ◽  
Gear Drive ◽  
Bending Stresses ◽  
Tooth Number ◽  
Gear Drives ◽  
The Mathematical Model

This paper proposes a method of the preliminary geometric design for gear tooth profiles based on given sliding coefficients. A design procedure is developed and a simplified derivation of the mathematical model of tooth profiles is presented. The characteristics of the gear drive designed by the proposed method are analyzed. A comparison study on the sliding coefficient with the involute gear drive is also carried out in this work. The effects of parameters, including tooth number and modulus, on the characteristics of the gear drives are studied. The contact and bending stresses of this new drive are also analyzed. A manufacturing method of the proposed gear is studied, and a simulation of the machining process demonstrates its feasibility. The results show that the designers can design tooth profiles according to required sliding coefficients by the proposed method.

Experimental Investigation of the Minimum Oil-Film Thickness in Spur Gears

1963 ◽  
Vol 85 (3) ◽  
pp. 451-455 ◽  
Author(s):  
D. W. Dareing ◽  
E. I. Radzimovsky
Keyword(s):  
Film Thickness ◽  
Voltage Drop ◽  
Planetary Gear ◽  
Gear Train ◽  
Spur Gears ◽  
Minimum Thickness ◽  
Testing Technique ◽  
Oil Film ◽  
Gear Teeth ◽  
Gear Drive

As a pair of gears is loaded, the minimum oil-film thickness between the gear teeth decreases and can approach a magnitude equal to the magnitude of the surface roughness. Metal-to-metal contact then occurs between the microscopic peaks on both mating teeth surfaces. Therefore, the minimum thickness of the film separating the mating teeth surfaces may be considered as one of the criteria of capacity for a gear drive. A testing technique that was developed for measuring oil-film thickness between loaded gear teeth while running is presented in this paper. The voltage drop across a thin oil film that is required to cause an electrical discharge was used to determine the oil-film thickness. A specially designed machine containing a planetary gear train was used in these experiments. The relationships between the minimum oil-film thickness and the load transmitted by the gearing under certain conditions were determined using this method.

Sign in / Sign up

Export Citation Format

Share Document