Download or read book An Experimental Investigation Into the Influence of Various Errors on the Transmission Error and Root Stresses of Spur Gears written by Mark Robert Milliren and published by . This book was released on 2011 with total page 95 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: In this study, an experimental investigation is performed to investigate the impact of various gear errors on transmission error and root fillet stresses. A test set-up is devised to operate a pair of spur gears under loaded, low-speed conditions. Two measurement systems; one an optical encoder-based transmission error measurement system and the other a multi-channel strain measurement system, are developed and implemented with the test set-up. A set of test gears having various types and tightly-controlled magnitudes of manufacturing errors are designed and procured. These errors include indexing errors of different tooth sequences, pitch line run-out errors and lead wobble errors. An extensive test matrix is executed to quantify the impact of these errors on the loaded static transmission error and the root stresses of the spur gears. At the end, the same test conditions are simulated by using a recent feature of gear analysis model (LDP) to assess the accuracy of its predictions.

Download or read book An Investigation Into the Impact of Random Spacing Errors on Static Transmission Error and Root Stresses of Spur Gear Pairs written by Michael James Handschuh and published by . This book was released on 2013 with total page 120 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: In this study, theoretical and experimental investigations of the effect of tooth spacing errors on the motion transmission error and root stresses of spur gear pairs are performed. A test setup with dedicated instrumentation for the measurement of the static transmission error and root stresses is devised. A number of experiments are performed with gears having deterministic spacing errors (at one or two teeth only) and random spacing errors (all teeth having a random distribution of errors as in a typical production gear). A test matrix defined by a range of torque at a very low speed is executed with each error configuration to experimentally quantify the influence of spacing errors on the static transmission error and the gear tooth root stresses. The results of these experiments form an extensive database on the impact of spacing errors on the static transmission error (a typical noise metric) and the root stresses (a durability metric). These experiments are simulated by using two existing gear contact models to demonstrate their accuracy and describe the empirical trends physically. A methodology is proposed at the end to relate increases in root stresses to the spacing error magnitudes directly. Closed-form expressions resulting from this methodology allow determination of the stress amplification factors due to a certain range of spacing error tolerances as well as quantifying how much spacing error can be tolerated within a user defined stress limit.

Download or read book International Gear Conference 2014 26th 28th August 2014 Lyon written by Philippe Velex and published by Chandos Publishing. This book was released on 2014-09-18 with total page 1225 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book presents papers from the International Gear Conference 2014, held in Lyon, 26th-28th August 2014. Mechanical transmission components such as gears, rolling element bearings, CVTs, belts and chains are present in every industrial sector and over recent years, increasing competitive pressure and environmental concerns have provided an impetus for cleaner, more efficient and quieter units. Moreover, the emergence of relatively new applications such as wind turbines, hybrid transmissions and jet engines has led to even more severe constraints. The main objective of this conference is to provide a forum for the most recent advances, addressing the challenges in modern mechanical transmissions. The conference proceedings address all aspects of gear and power transmission technology and range of applications (aerospace, automotive, wind turbine, and others) including topical issues such as power losses and efficiency, gear vibrations and noise, lubrication, contact failures, tribo-dynamics and nano transmissions. - A truly international contribution with more than 120 papers from all over the world - A judicious balance between fundamental research and industrial concerns - Participation of the most respected international experts in the field of gearing - A wide range of applications in terms of size, power, speed, and industrial sector

Download or read book An Experimental Investigation of the Effect of Spacing Errors on the Loaded Transmission Error of Spur Gear Pairs written by Brian Anichowski (Jr.) and published by . This book was released on 2017 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This paper complements recent investigations [Handschuh et al. (2014), Talbot et al. (2016)] of the influences of tooth indexing errors on dynamic factors of spur gears by presenting data on changes to the dynamic transmission error. An experimental study is performed using an accelerometer-based dynamic transmission error measurement system incorporated into a high-speed gear tester to establish baseline dynamic behavior of gears having negligible indexing errors, and to characterize changes to this baseline due to application of tightly-controlled intentional indexing errors. Spur gears having different forms of indexing errors are paired with a gear having negligible indexing error. Dynamic transmission error of gear pairs under these error conditions is measured and examined in both time and frequency domains to quantify the transient effects induced by these indexing errors. These measurements are then compared against the baseline, no error condition, as a means to quantify the dynamic vibratory behavior induced due to the tooth indexing errors. These comparisons between measurements indicate clearly that the baseline dynamic response, dominated by well-defined resonance peaks and mesh harmonics, are complemented by non-mesh orders of transmission error due the transient behavior induced by indexing errors. In addition, the tooth (or teeth) having indexing error imparts transient effects which dominate the vibratory response of the system for significantly more mesh cycles than the teeth having errors are in contact. For this reason, along with the results presented in Talbot et al. (2016), it was concluded that spur gears containing indexing errors exhibit significant deviations from nominal behavior, at both a system and time-domain level.

Download or read book Experimental Techniques Rotating Machinery and Acoustics Volume 8 written by James De Clerck and published by Springer. This book was released on 2015-04-09 with total page 275 pages. Available in PDF, EPUB and Kindle. Book excerpt: Experimental Techniques, Rotating Machinery & Acoustics, Volume 8: Proceedings of the 33rd IMAC, A Conference and Exposition on Structural Dynamics, 2015, the eighth volume of ten from the Conference brings together contributions to this important area of research and engineering. The collection presents early findings and case studies on fundamental and applied aspects of Structural Dynamics, including papers on: Experimental Techniques Processing Modal Data Rotating Machinery Acoustics Adaptive Structures Biodynamics Damping

Download or read book Experimental Mechanics on Emerging Energy Systems and Materials Volume 5 written by Tom Proulx and published by Springer Science & Business Media. This book was released on 2011-05-13 with total page 211 pages. Available in PDF, EPUB and Kindle. Book excerpt: This the fifth volume of six from the Annual Conference of the Society for Experimental Mechanics, 2010, brings together 25 chapters on Emerging Energy Systems. It presents early findings from experimental and computational investigations including Material State Changes in Heterogeneous Materials for Energy Systems, Characterization of Carbon Nanotube Foam for Improved Gas Storage Capability, Thermoresponsive Microcapsules for Autonomic Lithium-ion Battery Shutdown, Service Life Prediction of Seal in PEM Fuel Cells, and Assessing Durability of Elastomeric Seals for Fuel Cell Applications.

Download or read book An Experimental Investigation of the Impact of Random Spacing Errors on the Transmission Error of Spur and Helical Gear Pairs written by Muhammad Nevin Anandika and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise and vibration performance of a gear system is critical in any industry. Vibrations caused by the excitations at the gear meshes propagate to the transmission housing to cause noise, while also increasing gear tooth stresses to degrade durability. As such, gear engineers must seek gear designs that are nominally quiet with low vibration amplitudes. tudes. They must also ensure that this nominal performance is robust in the presence of various manufacturing errors. This thesis research aims at an experimental investigation of the influence of one type of manufacturing error, namely random tooth spacing errors, on the vibratory responses of spur and helical gear pairs. For this purpose, families of spur and helical gear test specimens having intentionally induced, tightly controlled random spacing error sequences are fabricated. These specimens are paired and assembled in various ways to achieve different sequences of composite spacing errors. Static and dynamic motion transmission error measurements from these tests are compared to the baseline case of “no error” gear to quantify the impact of random spacing errors on the dynamic response. These comparisons show that there is a significant, quantifiable impact of random spacing errors on both spur and helical gear dynamics. In general, vibration amplitudes of gear pairs having random spacing errors are higher than those of the corresponding no-error gear pairs. In the frequency domain, gears having random spacing errors exhibit broad-band spectra with significant non-mesh harmonics, pointing to potential noise quality issues.

Download or read book Journal of Mechanical Design written by and published by . This book was released on 2008-07 with total page 712 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Study of the Dynamic Response of Spur Gears Having Tooth Index Errors written by Allen Y. Sun and published by . This book was released on 2015 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: While there are numerous theoretical and experimental investigations of dynamic behavior of gear pairs of higher quality grades, very little is known about the same when certain classes of manufacturing errors are present. This study aims at investigating the effects of tooth index errors, one of the most common types of manufacturing errors. Using the changes in stresses along the tooth root regions as the metric, an experimental study is executed here to (i) establish a baseline dynamic behavior under no tangible index error and (ii) characterize the changes caused by tightly-controlled intentional index errors to this baseline dynamic behavior. For this, various gears having different forms of index errors are paired with an instrumented gear having no such errors. For each gear pair, tests are performed within wide ranges of torque and speed. A data processing scheme is proposed to normalize the measured stress signals to multiplication factor. It is shown that the baseline dynamic response represented solely by the dynamic stress factor is altered significantly by transient vibrations induced by the indexing errors, in some cases fully altering the baseline dynamic behavior and increasing the stress multiplication factors significantly. The experimental database formed in this study is expected to guide much needed theoretical studies on this topic.

Download or read book Vibration Engineering and Technology of Machinery Volume II written by Rajiv Tiwari and published by Springer Nature. This book was released on with total page 577 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Methodology for Evaluating Root Stresses of Rattling Gear Pairs written by Colton W. Thomas and published by . This book was released on 2021 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Gear rattle is a major noise problem in certain powertrains where an internal combustion engine drives a timing gear drive or a manual transmission. It is primarily a result of gear teeth losing contact intermittently and committing impacts along the drive and coast sides of the gear pair having a certain amount of backlash. Most of the studies on gear rattle focused on the noise and vibration aspects of the problem, with a very little attention given to adverse durability consequences. In this study, an experimental investigation is performed to measure root stresses while a pair of spur gears are in various types of rattling motions. A test setup is employed to operate a pair of high-accuracy spur gears under the influence of a periodically time varying input torque to produce periodic and non-periodic rattling motions. A multi-channel strain measurement system is incorporated in a methodology to measure root stresses in the instances of impact events. Changes to root stress time histories due to drive and coast-side impacts are documented to show that impacts significantly increase the root stress amplitudes and frequencies. The resultant experimental database generated under tightly-controlled conditions is suitable for validating future modeling studies that are required to predict statistical distributions for root stress duty cycles of gear teeth.

Download or read book An Experimental Investigation of the Combined Effects of Rim Thickness and Pitch Diameter on Spur Gear Tooth Root and Fillet Stresses written by Raymond J. Drago and published by . This book was released on 1981-10-01 with total page 25 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book An Experimental Investigation on the Influence of Tensile Mean Stress on Gear Tooth Bending Fatigue Life written by Zachary Dean Teaford and published by . This book was released on 2020 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: In this study, an experimental investigation on the influence of tensile mean stress on gear tooth bending fatigue life is performed. A newly developed single-tooth bending test machine is utilized to perform gear tooth bending fatigue experiments under various loading conditions. A new single-tooth bending test fixture is developed for a chosen test gear. A detailed experimental methodology is presented on dynamic and static strain measurements of the chosen test gear root fillet profile in order to (i) quantify any dynamic loading effects at high loading frequencies, and (ii) validate maximum root stress predictions. Two sets of fatigue tests are performed at load levels of R = 0.05 and R = 0.5 whose results are analyzed statistically to generate L50 and L10 curves for each loading case. Utilizing the L50 stress-life curves, a map of constant life is obtained, showing a straight-line relationships between mean stress and alternating stress. It is shown that an increase in the tensile mean stress reduces the fatigue lives of gear teeth.

Download or read book Journal of Mechanisms Transmissions and Automation in Design written by and published by . This book was released on 1983 with total page 766 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book A Transmission error based Gear Dynamic Model written by Nina Sainte-Marie and published by . This book was released on 2019 with total page 207 pages. Available in PDF, EPUB and Kindle. Book excerpt: Noise measurements have shown that helicopters main gearboxes highly contribute to the overall cabin noise. Gear mesh vibrations propagate through the shafts to the rolling element bearings and the casing which becomes a source of radiated noise. The latter is characterized by high-amplitude tones emerging from broadband noise whose frequencies lie in the range of maximum human ear sensitivity. In the context of continuous improvement in the acoustic comfort of helicopter passengers, it is therefore necessary to analyse and optimize gearbox vibrations in order to reduce casing noise radiations. The research work presented in this memoir is focused on the development of a numerical model dedicated to the prediction of gear system dynamic behaviour, comprising several gear stages and different types of gears. This model relies on classic beam and lumped parameter elements along with specific two-node gear elements for both cylindrical (spur, helical) and spiral-bevel gears. The equations of motion are developed based on time-varying functions representative of mesh excitations which comprise: (a) mesh stiffness functions, (b) quasi-static transmission error under load, and (c) kinematic (or no-load) transmission error. A number of comparisons with benchmark numerical and experimental results from the literature are presented which demonstrate that the proposed approach is sound as far as single-stage systems with spur, helical or spiral-bevel gears are considered. Validations are then extended to double-stage gears and, here again, it is confirmed that the proposed transmission error based formulation is accurate and can account for tooth shape modifications. In the second part of the memoir, several examples of application are presented and commented upon. First, the combined influence of tooth pitch errors and load on the dynamic behaviour of gear transmissions is tackled. An extended three-dimensional model and a reduced torsional version are then confronted in order to investigate the dependency between dynamic transmission errors and mesh force / root stress dynamic factors. Further investigations on bearing dynamic response in two-stage spur gear systems are conducted and the particular contributions of profile modifications are analysed. Finally, a system combining a cylindrical gear and a spiral-bevel gear is considered and particular attention is paid to the dynamic couplings between the various meshes and their influence on bearing dynamic responses.

Download or read book An Experimental Investigation of the Impact of Engineered Surface Processes on Efficiency of Spur Gears written by Kreteeka Chaudhury and published by . This book was released on 2019 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: This study was conducted to evaluate the effect of surface finish on spur gear power losses under jet lubrication. Four different surface finish combinations were tested: (i) hard ground surface pair, (ii) chemically polished surface pair, (iii) super honed surface pair and (iv) hard ground against chemically polished surface pair. The test was conducted at 432 different operating condition combinations of speed, torque, lubricant type and inlet temperature. An FZG back-to-back set up was used to conduct the test. Surface roughness inspections were carried out at regular intervals to monitor any changes in surface roughness characteristics. The measured power losses were resolved into spin (load independent) and mechanical (load dependent) power losses. The relation between both losses and various operating conditions were explored. As expected, spin power loss did not vary with variation in surface finish. Mechanical power loss increased with increase in speed and torque. Various surface roughness and operating parameters such as BAC curves and lambda ratio were calculated for each surface finish combination to study their correlation to power losses measured. For smoother surfaces, an increase in temperature decreased power loss as the viscosity of the lubricant decreased and hence rolling friction losses dominating the mechanical power loss decreased. However, for rougher surfaces sliding friction losses seemed to be dominant due to high amounts of asperity contact. Thus, more cases of higher power loss at high temperatures were observed for rougher surfaces.

Download or read book A Study on the Relationship Between the Dynamic Factor and the Dynamic Transmission Error of Spur Gear Pairs written by Venkata Krishna Tamminana and published by . This book was released on 2005 with total page 180 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Power Transmission systems are widely used in automotive and aerospace industries. These systems are often operated under relatively high rotational speeds and hence their dynamic behavior, especially its impact on the gears, becomes a relevant issue. Dynamic behavior of gear systems is important for two main reasons: durability and noise. In this study, two different dynamic models, a finite elements-based deformable-body model and a simplified discrete model, are developed to predict dynamic behavior of spur gear pairs. The deformable-body model will have the ability to predict both DTE and DF based on mesh and tooth forces as well as dynamic gear tooth bending stresses. The discrete model will rely on the deformable-body model for computation of gear mesh parameters under quasi-static conditions and will predict both DTE and DF based on mesh and tooth forces. Dynamic transmission error (DTE) and dynamic factors (DF) defined based on the gear mesh loads, tooth loads and bending stresses are computed for a number of unmodified and modified spur gears within a wide range of rotational speed for different involute contact ratios and torques. Both models are validated by comparing their DTE predictions with experimental data obtained from a set of tests using spur gear having unmodified and modified tooth profiles. The predicted Dc DF and DTE values are related to each other through simplified formulas. Impact of nonlinear behavior such as tooth separations and jump discontinuities on DF is also quantified.