Study on high-speed traction drive CVT for aircraft power generation

Traction drive makes oil film between two rollers, and power is transmitted by oil film shearing. It has the following characteristics. (1) Traction drive can be operated at low level of vibration and noise, so they are more suitable at higher speed rotations than gear. (2) Traction drive can change continuously the distance from the contact point of the rotating part to the axis of rotation; it is useful in continuously variable transmission (CVT). Generally-fixed-reduction-ratio-type traction drive is developed for the purpose of use by high-speed rotation taking advantage of the feature of characteristic (1). On the other hand, the authors have developed a micro drive system for transmission; a micro-traction-drive based on the structure of an angular ball bearing is advantageous over geared speed reducers, for small scale equipment requiring high numbers of revolutions. A micro-traction-drive is easily manufactured by modifying angular bearings and tapered roller bearings for which preload inner race and outer race act as thrust force. The driving force is transmitted by the contact of the retainer with the rolling element in the rotating direction. The test of the experimental model of micro-traction-drive using an angular ball bearing of 10mm inner diameter, 30mm outer diameter, and 9mm width was carried out. Power-absorbing-type test equipment was made and the input and output torque, number of revolutions, temperature, noise, and state of lubrication were measured. With the same test equipment, the micro-traction-drive was compared to the equivalent type planetary gear with outer diameter of 32mm on the market. In comparison with commercially available speed reducers, the planetary gear system, the newly developed micro-traction was found to bear superior performance in terms of allowable transmission torque, efficiency, noise, and other characteristics.

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Study on high speed traction drive CVT for aircraft power generation (Analysis of ratio-changing response)

Transactions of the JSME (in Japanese) ◽

10.1299/transjsme.17-00472 ◽

2018 ◽

Vol 84 (861) ◽

pp. 17-00472-17-00472 ◽

Cited By ~ 1

Author(s):

Kippei MATSUDA ◽

Kenichiro TANAKA ◽

Hideyuki IMAI ◽

Tatsuhiko GOI ◽

Yasukazu SATO ◽

...

Keyword(s):

Power Generation ◽

High Speed ◽

Traction Drive

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Evaluation of Ultra High Speed Micro Traction Drive

World Tribology Congress III, Volume 2 ◽

10.1115/wtc2005-63288 ◽

2005 ◽

Author(s):

Yasuyoshi Tozaki ◽

Akihiko Umeda ◽

Takeshi Yoshimi ◽

Isamu Shiotsu ◽

Hiroyuki Sonobe ◽

...

Keyword(s):

Driving Force ◽

High Speed ◽

Ball Bearing ◽

Reduction Ratio ◽

Traction Drive ◽

Measurement Temperature ◽

Input Shaft ◽

Ultra High Speed ◽

Rolling Element ◽

Type Test

Micro traction drive is a device to transmit driving force modified from angular ball bearing. The micro traction drive consists of an input/inner ring, an outer ring, a rolling element, a retainer/output shaft, and a casing. In addition, the micro traction drive of the tandem type that combined two bearings was developed to obtain a big reduction ratio. As a result, we are able to attain the reduction ratio 7.3. Traction oil on the market was sealed in the test piece for oil bath lubrication. Input shaft could be driven with a motor in ultra high speed. Power absorbing type test equipment was made the efficiency and temperature of micro traction drive operated at high speed were successfully measured. In the result of measurement, temperature rise are a few and it turns out a micro traction drive can be used by ultra high-speed.

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Ball bearing turbocharger vibration management: application on high speed balancer

Mechanics & Industry ◽

10.1051/meca/2020091 ◽

2020 ◽

Vol 21 (6) ◽

pp. 619

Author(s):

Kostandin Gjika ◽

Antoine Costeux ◽

Gerry LaRue ◽

John Wilson

Keyword(s):

Dynamic Behavior ◽

High Speed ◽

Internal Combustion Engines ◽

Ball Bearing ◽

Squeeze Film ◽

Design And Technology ◽

Squeeze Film Damper ◽

Damping Coefficients ◽

Bearing Loads ◽

Stiffness And Damping

Today's modern internal combustion engines are increasingly focused on downsizing, high fuel efficiency and low emissions, which requires appropriate design and technology of turbocharger bearing systems. Automotive turbochargers operate faster and with strong engine excitation; vibration management is becoming a challenge and manufacturers are increasingly focusing on the design of low vibration and high-performance balancing technology. This paper discusses the synchronous vibration management of the ball bearing cartridge turbocharger on high-speed balancer and it is a continuation of papers [1–3]. In a first step, the synchronous rotordynamics behavior is identified. A prediction code is developed to calculate the static and dynamic performance of “ball bearing cartridge-squeeze film damper”. The dynamic behavior of balls is modeled by a spring with stiffness calculated from Tedric Harris formulas and the damping is considered null. The squeeze film damper model is derived from the Osborne Reynolds equation for incompressible and synchronous fluid loading; the stiffness and damping coefficients are calculated assuming that the bearing is infinitely short, and the oil film pressure is modeled as a cavitated π film model. The stiffness and damping coefficients are integrated on a rotordynamics code and the bearing loads are calculated by converging with the bearing eccentricity ratio. In a second step, a finite element structural dynamics model is built for the system “turbocharger housing-high speed balancer fixture” and validated by experimental frequency response functions. In the last step, the rotating dynamic bearing loads on the squeeze film damper are coupled with transfer functions and the vibration on the housings is predicted. The vibration response under single and multi-plane unbalances correlates very well with test data from turbocharger unbalance masters. The prediction model allows a thorough understanding of ball bearing turbocharger vibration on a high speed balancer, thus optimizing the dynamic behavior of the “turbocharger-high speed balancer” structural system for better rotordynamics performance identification and selection of the appropriate balancing process at the development stage of the turbocharger.

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Recent Patents on the Angular Contact Ball Bearing of High-Speed Motorized Spindle

Recent Patents on Mechanical Engineering ◽

10.2174/2212797613666201208000558 ◽

2020 ◽

Vol 13 ◽

Author(s):

Yudong Bao ◽

Linkai Wu ◽

Yanling Zhao ◽

Chengyi Pan

Keyword(s):

High Speed ◽

Ball Bearing ◽

Rapid Development ◽

Ceramic Materials ◽

Development Trend ◽

Numerical Control ◽

Angular Contact Ball Bearing ◽

Practical Applications ◽

High Speed Cutting ◽

Advantages And Disadvantages

Background:: Angular contact ball bearings are the most popular bearing type used in the high speed spindle for machining centers, The performance of the bearing directly affects the machining efficiency of the machine tool, Obtaining a higher value is the direction of its research and development. Objective:: By analyzing the research achievements and patents of electric spindle angular contact bearings, summarizing the development trend provides a reference for the development of electric spindle bearings. Methods:: Through the analysis of the relevant technology of the electric spindle angular contact ball bearing, the advantages and disadvantages of the angular contact ball bearing are introduced, and the research results are combined with the patent analysis. Results:: With the rapid development of high-speed cutting and numerical control technology and the needs of practical applications, the spindle requires higher and higher speeds for bearings. In order to meet the requirements of use, it is necessary to improve the bearing performance by optimizing the structure size and improving the lubrication conditions. Meanwhile, reasonable processing and assembly methods will also have a beneficial effect on bearing performance. Conclusion:: With the continuous deepening of bearing technology research and the use of new structures and ceramic materials has made the bearing's limit speed repeatedly reach new highs. The future development trend of high-speed bearings for electric spindles is environmental protection, intelligence, high speed, high precision and long life.

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Temperature Rise Prediction of Oil-Air Lubricated Angular Contact Ball Bearings Using Artificial Neural Network

Recent Patents on Mechanical Engineering ◽

10.2174/2212797612666190530115739 ◽

2019 ◽

Vol 12 (3) ◽

pp. 248-261

Author(s):

Baomin Wang ◽

Xiao Chang

Keyword(s):

Neural Network ◽

Artificial Neural Network ◽

Temperature Rise ◽

High Speed ◽

Ball Bearing ◽

Influence Factors ◽

Ball Bearings ◽

Ann Model ◽

Angular Contact Ball Bearing ◽

Artificial Neural

Background: Angular contact ball bearing is an important component of many high-speed rotating mechanical systems. Oil-air lubrication makes it possible for angular contact ball bearing to operate at high speed. So the lubrication state of angular contact ball bearing directly affects the performance of the mechanical systems. However, as bearing rotation speed increases, the temperature rise is still the dominant limiting factor for improving the performance and service life of angular contact ball bearings. Therefore, it is very necessary to predict the temperature rise of angular contact ball bearings lubricated with oil-air. Objective: The purpose of this study is to provide an overview of temperature calculation of bearing from many studies and patents, and propose a new prediction method for temperature rise of angular contact ball bearing. Methods: Based on the artificial neural network and genetic algorithm, a new prediction methodology for bearings temperature rise was proposed which capitalizes on the notion that the temperature rise of oil-air lubricated angular contact ball bearing is generally coupling. The influence factors of temperature rise in high-speed angular contact ball bearings were analyzed through grey relational analysis, and the key influence factors are determined. Combined with Genetic Algorithm (GA), the Artificial Neural Network (ANN) model based on these key influence factors was built up, two groups of experimental data were used to train and validate the ANN model. Results: Compared with the ANN model, the ANN-GA model has shorter training time, higher accuracy and better stability, the output of ANN-GA model shows a good agreement with the experimental data, above 92% of bearing temperature rise under varying conditions can be predicted using the ANNGA model. Conclusion: A new method was proposed to predict the temperature rise of oil-air lubricated angular contact ball bearings based on the artificial neural network and genetic algorithm. The results show that the prediction model has good accuracy, stability and robustness.

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Sound Noise Generated from Ball Bearing in High Speed Rotation

Bulletin of JSME ◽

10.1299/jsme1958.21.1306 ◽

1978 ◽

Vol 21 (158) ◽

pp. 1306-1310 ◽

Cited By ~ 7

Author(s):

Akio NAGAMATSU ◽

Masaho FUKUDA

Keyword(s):

High Speed ◽

Ball Bearing ◽

High Speed Rotation ◽

Speed Rotation

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