Laser Holographic Measurement of Tooth Flank Form of Cylindrical Involute Gear: Part 2 — For Helical Gear Tooth

1992 ◽  
Author(s):  
H. Fujio ◽  
A. Kubo ◽  
S. Tochimoto ◽  
H. Hanaki ◽  
S. Saitoh ◽  
...  
Keyword(s):  
Gear Tooth ◽  
Measuring Method ◽  
Helix Angle ◽  
Helical Gear ◽  
Helical Gears ◽  
Error Surface ◽  
Tooth Flank ◽  
Form Deviation ◽  
Laser Holography ◽  
Holographic Measurement

Abstract The interferometry using laser holography is applied to measure the form deviation of tooth flank of involute helical gears. One problem of this method is that the increase of helix angle reduces the region of the flank to which the laser beam can irradiate at a same time. To solve this problem, following method is developed: The objective tooth flank is divided into some regions, and the interferometry measurement is worked out for each region. The measured values for the form deviation of each region of the tooth flank are transformed to the values on the plane of action of this gear. These values for each region of the tooth flank are then concatenated successively until they result the curved surface for the form deviation of the whole tooth flank of the helical gear. The error surface of the tooth flank of helical gear obtained by this procedure is compared with that of conventional measuring method using contacting stylus.

Laser Holographic Measurement of Tooth Flank Form of Cylindrical Involute Gear

1994 ◽  
Vol 116 (3) ◽  
pp. 721-729 ◽  
Author(s):  
H. Fujio ◽  
A. Kubo ◽  
S. Saitoh ◽  
M. Suzuki ◽  
S. Tochimoto ◽  
...  
Keyword(s):  
Laser Beam ◽  
Incident Angle ◽  
Measuring Method ◽  
Helical Gears ◽  
Phase Stepping ◽  
Interference Fringes ◽  
Phase Stepping Method ◽  
Tooth Flank ◽  
Form Deviation ◽  
Holographic Measurement

The form deviations of tooth flanks of spur and helical gears obtained by using a laser holographic interferometer are compared with the results of the conventional measuring method using a contacting stylus. The objective tooth flank which has a rough finish compared with optical parts is irradiated with a laser beam in a large incident angle to obtain the reflected ray from it. Image patterns of the interference fringes for tooth flanks with various types of form deviation are obtained, and they are transformed to the form deviations from the target tooth flank form. The algorithm of this transformation is shown: the brightness information of the image of the interference fringe on the CRT is converted to the amplitude of form deviation defined on the plane of action of the gear according to the phase difference of light beam by using the phase stepping method. A partial measuring procedure for helical gears is proposed which achieves the same level of accuracy as the conventional method using a stylus.

Laser Holographic Measurement of Tooth Flank Form of Cylindrical Involute Gear: Part 1 — Principle and Measurement of Spur Gear

1992 ◽  
Author(s):  
A. Kubo ◽  
H. Fujio ◽  
S. Tochimoto ◽  
T. Honda ◽  
S. Saitoh ◽  
...  
Keyword(s):  
Interference Fringe ◽  
Incident Angle ◽  
Gear Tooth ◽  
Measuring Method ◽  
Spur Gear ◽  
Phase Stepping ◽  
Phase Stepping Method ◽  
Tooth Flank ◽  
Form Deviation ◽  
Holographic Measurement

Abstract Form deviation of tooth flank of spur gear is measured by laser holographic interferometer. To get the reflected ray from the objective tooth flank, laser beam is irradiated with large incident angle to the objective tooth flank which has considerably rough surface finish in comparison with that of optical parts. Some tooth flanks with various kinds of form deviation were measured, and image patterns of interference fringe were obtained. The conversion of the coordinates of the image figure of the gear tooth flank on CRT to the coordinate system of the gear is worked out by fitting the contour form of simulated figure to that of observed images. The algorithm of transformation from interference fringe pattern to tooth flank form deviation is shown: The brightness of the interference fringe image on the CRT is converted to the amplitude of form deviation defined on the plane of action of the gear via phase difference of light beam which is obtained by phase stepping method. The form deviations of tooth flanks of spur gear obtained by this interference method were compared with the results of conventional measuring method using contacting stylus.

Laser Interferometric Measuring Method of Involute Artifact and Stabilization of Measurement

2011 ◽  
Vol 5 (2) ◽  
pp. 144-149
Author(s):  
Masaharu Komori ◽  
◽  
Fumi Takeoka ◽  
Aizoh Kubo ◽  
Hiroshige Fujio ◽  
...  
Keyword(s):  
Gear Tooth ◽  
Measuring Method ◽  
Tooth Profile ◽  
National Standard ◽  
Helical Gears ◽  
Involute Gears ◽  
Measuring Machine ◽  
Form Quality ◽  
Tooth Flank ◽  
Laser Interferometric

Vibration and noise are serious problems with involute spur and helical gears used, e.g., in drivetrains of vehicles such as automobiles. The gear tooth flank form of micrometer order markedly affects gear vibration and noise; therefore, the tooth flank form quality must be strictly controlled to maximize gear performance. Tooth profile measuring machines used in calibration for form error inspection of involute gears usually use an involute artifact, which itself must be calibrated highly accurately. However, it is typically difficult for current tooth profile measuring machine using contact stylus to calibrate the involute artifact with a high accuracy while satisfying traceability to a national standard. A highly precise and traceable measuring technology for the involute artifact is therefore required. The direct measurement of the involute artifact we propose uses a laser interferometer, whose measurement stability is confirmed in experiments measuring the detailed form of an involute tooth flank.

Contact Stress Analysis of a Helical Gear

2015 ◽  
Vol 766-767 ◽  
pp. 1070-1075 ◽  
Author(s):  
R. Devaraj
Keyword(s):  
Stress Analysis ◽  
Contact Stress ◽  
Gear Tooth ◽  
Element Model ◽  
Helix Angle ◽  
Helical Gear ◽  
Bending Stress ◽  
Helical Gears ◽  
Modeling Software ◽  
Main Factors

The main factors that cause the failure of gears are the bending stress and contact stress of the gear tooth. Out of these, failure of gears due to contact stress is high compared to bending stress. Stress analysis has been a key area of research to minimize failure and optimize design. This paper gives a finite element model for introspection of the stresses in the tooth during the meshing of gears. Specifically, helix angle is important for helical gears. Using modeling software, 3-D models for different helix angles in helical gears were generated, and the simulation was performed using ANSYS 12.0 to estimate the contact stress. The Hertz equation and AGMA standard was used to calculate the contact stress. The results of the theoretical contact stress values, using Hertz and AGMA are compared with the stress values from the FEA for different helix angles and the results are tabulated and discussed.

Evaluation of Pitch Deviations with Comprehensive Representation Suitable for Engagement Evaluation in Different Types of Gears

2011 ◽  
Vol 5 (2) ◽  
pp. 132-137 ◽  
Author(s):  
Syuhei Kurokawa ◽  
◽  
Yasutsune Ariura ◽  
Toshiro Doi
Keyword(s):  
Gear Tooth ◽  
Length Unit ◽  
Helical Gears ◽  
Pitch Error ◽  
Surface Deviations ◽  
Tooth Flank ◽  
Pitch Deviation ◽  
Form Deviation ◽  
Flank Surface ◽  
Gear Engagement

Gear tooth flank deviations should be characterized to evaluate individual gear accuracy directly linked to gear performance during engagement. The comprehensive pitch deviation representation we propose is calculated using multiple tooth flank surface deviations as 0-order form deviations. In this representation, pitch error is expressed by angle unit, not by length unit, and calculated from measured conventional deviation (profiles and leads) withoutmeasuring pitch deviation. For spur and helical gears, pitch deviation is expressed by a single length unit and also by a single angle unit. On the other hand, for bevel gear flank, pitch deviation expressed by length unit consists of many different values even on a single flank. Using the angle unit expression, form deviation is described exactly by a single parameter. The comprehensive representation we propose overcomes the disadvantages of conventional pitch deviation evaluation, going right to the point of gear engagement evaluation.

Simulated Helical Gear Pump Analysis Using a New CFD Approach

2009 ◽  
Author(s):  
Aaron S. Heisler ◽  
John J. Moskwa ◽  
Frank J. Fronczak
Keyword(s):  
High Speed ◽  
System Development ◽  
Gear Tooth ◽  
Fluid Motion ◽  
Computation Time ◽  
Helix Angle ◽  
Helical Gear ◽  
Gear Pump ◽  
Helical Gears ◽  
Gear Pumps

The purpose of this paper is to focus on cavitation prediction at high-speeds in helical gear pumps for the purpose of hydrostatic dynamometer system development. Details of the fluid motion will be described through various stages of fluid transfer from the pump inlet to the outlet using various mesh densities. Using the results of these simulations, a discussion of design improvements for high-speed hydrostatic dynamometer operation is included. Conducting CFD simulations on external gear pumps is a difficult problem depending upon the complexity of the individual components. Simulating helical gears is especially taxing due to the complexity of the gear tooth profile. The additional detail in a helical gear pump model leads to an increase of the required mesh density and therefore increased computation time. A less computationally complex approach to simulating helical gears is to consider a helical gear as a series of thin spur gears rotated according to a predetermined helix angle. Details of this approach and results are discussed in this paper.

Generation of the Anti-Twist Crowned Helical Gear by Modifying the Gear Rotation Angle in the Hobbing Process

2017 ◽  
Vol 749 ◽  
pp. 161-170
Author(s):  
Ruei Hung Hsu ◽  
Yu Ren Wu ◽  
Shih Sheng Chen
Keyword(s):  
Rotation Angle ◽  
Gear Tooth ◽  
Helical Gear ◽  
Gear Hobbing ◽  
Tooth Flank ◽  
Center Distance

In the gear-hobbing process, the work gear tooth flank is usually longitudinally crowned by varying the center distance between the hob and the work gear. Without crossed angle compensation, however, this center distance variation produces a twisted tooth flank on the work gear. This paper therefore proposes a methodology to reduce this tooth flank twist and achieve anti-twist in longitudinal crowning by modifying the gear rotation angle in the hobbing process which is practiced using a CNC hobbing machine with three synchronous axes.

A parameterized numerical method for generating discrete helical gear tooth surface allowing non-standard geometry

2008 ◽  
Vol 222 (6) ◽  
pp. 1033-1038 ◽  
Author(s):  
J Hedlund ◽  
A Lehtovaara
Keyword(s):  
Gear Tooth ◽  
Numerical Approach ◽  
Helical Gear ◽  
Tooth Surface ◽  
Tool Profile ◽  
Standard Geometry ◽  
Gear Manufacturing ◽  
Involute Gears ◽  
Gear Geometry ◽  
Tooth Flank

Gear analysis is typically performed using calculation based on gear standards. Standards provide a good basis in gear geometry calculation for involute gears, but these are unsatisfactory for handling geometry deviations such as tooth flank modifications. The efficient utilization of finite-element calculation also requires the geometry generation to be parameterized. A parameterized numerical approach was developed to create discrete helical gear geometry and contact line by simulating the gear manufacturing, i.e. the hobbing process. This method is based on coordinate transformations and a wide set of numerical calculation points and their synchronization, which permits deviations from common involute geometry. As an example, the model is applied to protuberance tool profile and grinding with tip relief. A fairly low number of calculation points are needed to create tooth flank profiles where error is <1 μm.

scholarly journals Enhanced application limits for crossed helical gearboxes using new geometries for smaller sliding paths or smaller contact pressures

2019 ◽  
Vol 287 ◽  
pp. 01010
Author(s):  
Christoph Boehme ◽  
Dietmar Vill ◽  
Peter Tenberge
Keyword(s):  
Calculation Method ◽  
Helix Angle ◽  
Helical Gear ◽  
Design Parameters ◽  
Helical Gears ◽  
Positive Effects ◽  
Tooth Stiffness ◽  
Lubrication Condition ◽  
Overlap Ratio ◽  
Helical Gear Pair

Crossed-axis helical gear units are used as actuators and auxiliary drives in large quantities in automotive applications such as window regulators, windscreen wipers and seat adjusters. Commonly gear geometry of crossed helical gears is described with one pitch point. This article deals with an extended calculation method for worm gear units. The extended calculation method increases the range of solutions available for helical gears. In general, for a valid crossed helical gear pair, the rolling cylinders do not have to touch each other. In mass production of many similar gears, individual gears can be reused because they can be paired with other centre distances and ratios. This also allows the use of spur gears in combination with a worm, making manufacturing easier and more efficient. By selecting design parameters, for example the axis crossing angle or the helix angle of a gear, positive effects can be achieved on the tooth contact pressure, the overlap ratio, the sliding paths, the lubrication condition, the tooth stiffness and, to a limited extent, on the efficiency of the gearing. It can be shown that for involute helical gears, in addition to the known insensitivity of the transmission behaviour to centre distance deviations, there is also insensitivity to deviations of the axis crossing angle. This means that installation tolerances for crossed helical gearboxes can be determined more cost-effectively.

Sign in / Sign up

Export Citation Format

Share Document