Performance Evaluation of Innovative Micro-Traction-Drive-Utilized Angular-Contact Bearing

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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Direct Outer Ring Cooling of a High Speed Jet Engine Mainshaft Ball Bearing: Experimental Investigation Results

Volume 4: Heat Transfer, Parts A and B ◽

10.1115/gt2010-23312 ◽

2010 ◽

Author(s):

Peter Gloeckner ◽

Klaus Dullenkopf ◽

Michael Flouros

Keyword(s):

Power Dissipation ◽

High Speed ◽

Ball Bearing ◽

Operating Conditions ◽

Outer Ring ◽

Outer Diameter ◽

Propulsion Systems ◽

Jet Engine ◽

Power Loss Reduction ◽

The Impact

Operating conditions in high speed mainshaft ball bearings applied in new aircraft propulsion systems require enhanced bearing designs and materials. Rotational speeds, loads, demands on higher thrust capability, and reliability have increased continuously over the last years. A consequence of these increasing operating conditions are increased bearing temperatures. A state of the art jet engine high speed ball bearing has been modified with an oil channel in the outer diameter of the bearing. This oil channel provides direct cooling of the outer ring. Rig testing under typical flight conditions has been performed to investigate the cooling efficiency of the outer ring oil channel. In this paper the experimental results including bearing temperature distribution, power dissipation, bearing oil pumping and the impact on oil mass and parasitic power loss reduction are presented.

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Analysis of High-Speed Electrical Generators for Utility Applications

Volume 2: Reliability, Availability and Maintainability (RAM); Plant Systems, Structures, Components and Materials Issues; Simple and Combined Cycles; Advanced Energy Systems and Renewables (Wind, Solar and Geothermal); Energy Water Nexus; Thermal Hydraulics and CFD; Nuclear Plant Design, Licensing and Construction; Performance Testing and Performance Test Codes ◽

10.1115/power2013-98152 ◽

2013 ◽

Author(s):

Miroslav P. Petrov

Keyword(s):

Electricity Generation ◽

High Speed ◽

Renewable Energy Sources ◽

Scale Up ◽

Energy Utilization ◽

Superior Performance ◽

Electricity Production ◽

Small Scale ◽

Technical Challenges ◽

Compact Design

High-speed alternators are believed to be well developed nowadays, following the improvement in performance and decrease of costs for electronic power converters and permanent magnet materials. Their compact design and their ability to vary the rotational speed in off-design conditions promise superior performance when compared to conventional generators. High-speed alternators are only available in limited sizes for small-scale applications, whereas improvements in efficiency and optimized part-load behavior are particularly important especially for small-scale electricity generation. Enhanced energy utilization for electricity production by small utility plants or by distributed units located at private homes or commercial buildings, based on thermodynamic cycles powered by natural gas or various renewable energy sources, is possible to be achieved through a wider application of grid-integrated high-speed technology. This study presents a critical review of previous research and demonstration work on high-speed electrical machines and a summary of the technical challenges limiting their performance and their expansion into larger sizes. Conclusions are drawn for finding appropriate solutions for practical high-speed electricity generation units and their readiness for a much wider deployment. Closer analysis is attempted on the thermal and mechanical integrity of high-speed alternators and the technical challenges that slow down their scale-up to MW-size units for utility applications. The necessary research and development work that needs to be done in the near future is outlined and discussed herein.

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Study on high-speed traction drive CVT for aircraft power generation - Gyroscopic effect of the thrust ball bearing on the CVT -

Journal of Advanced Mechanical Design Systems and Manufacturing ◽

10.1299/jamdsm.2017jamdsm0087 ◽

2017 ◽

Vol 11 (6) ◽

pp. JAMDSM0087-JAMDSM0087 ◽

Cited By ~ 1

Author(s):

Kippei MATSUDA ◽

Tatsuhiko GOI ◽

Kenichiro TANAKA ◽

Hideyuki IMAI ◽

Hirohisa TANAKA ◽

...

Keyword(s):

Power Generation ◽

High Speed ◽

Ball Bearing ◽

Gyroscopic Effect ◽

Traction Drive

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Development of High Speed Rotation Micro Traction Drive Modified from Angular Ball Bearing (1st Report, Experimental Manufacture and Evaluation)

TRANSACTIONS OF THE JAPAN SOCIETY OF MECHANICAL ENGINEERS Series C ◽

10.1299/kikaic.72.1337 ◽

2006 ◽

Vol 72 (716) ◽

pp. 1337-1344 ◽

Cited By ~ 2

Author(s):

Isauu SIOTSU ◽

Susumu MATSUMOTO ◽

Yasuyoshi TOZAKI ◽

Takeshi YOSHIMI ◽

Akihiko UMEDA ◽

...

Keyword(s):

High Speed ◽

Ball Bearing ◽

Traction Drive ◽

High Speed Rotation ◽

Speed Rotation

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Direct Outer Ring Cooling of a High Speed Jet Engine Mainshaft Ball Bearing: Experimental Investigation Results

Journal of Engineering for Gas Turbines and Power ◽

10.1115/1.4002355 ◽

2011 ◽

Vol 133 (6) ◽

Cited By ~ 8

Author(s):

Peter Gloeckner ◽

Klaus Dullenkopf ◽

Michael Flouros

Keyword(s):

Power Dissipation ◽

High Speed ◽

Ball Bearing ◽

Operating Conditions ◽

Outer Ring ◽

Outer Diameter ◽

Propulsion Systems ◽

Jet Engine ◽

Power Loss Reduction ◽

The Impact

Operating conditions in high speed mainshaft ball bearings applied in new aircraft propulsion systems require enhanced bearing designs and materials. Rotational speeds, loads, demands on higher thrust capability, and reliability have increased continuously over the last years. A consequence of these increasing operating conditions are increased bearing temperatures. A state of the art jet engine high speed ball bearing has been modified with an oil channel in the outer diameter of the bearing. This oil channel provides direct cooling of the outer ring. Rig testing under typical flight conditions has been performed to investigate the cooling efficiency of the outer ring oil channel. In this paper, the experimental results including bearing temperature distribution, power dissipation, and bearing oil pumping and the impact on oil mass and parasitic power loss reduction are presented.

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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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Experimental Measurement of CTOA During Ductile Crack Propagation in Pipeline Burst Tests

Volume 3: Operations, Monitoring, and Maintenance; Materials and Joining ◽

10.1115/ipc2018-78510 ◽

2018 ◽

Author(s):

Kazuki Shibanuma ◽

Hikaru Yamaguchi ◽

Takahiro Hosoe ◽

Katsuyuki Suzuki ◽

Shuji Aihara

Keyword(s):

Steady State ◽

Crack Propagation ◽

Crack Velocity ◽

High Speed ◽

Crack Arrest ◽

Opening Angle ◽

Small Scale ◽

Outer Diameter ◽

Burst Test ◽

Pipe Burst

Dynamic measurement of drop-weight tear test (DWTT) and pipe burst test for 356 mm outer diameter and 9.5 mm wall thickness steel pipe were conducted using high-speed camera. Crack velocity in the DWTT were 10 m/s during the steady state. Crack Tip Opening Angle (CTOA) values measured in the DWTT showed the constant value of about 20.1° during steady state propagation. On the other hand, crack velocity in the burst test showed monotonically decreasing during crack propagation from 200 m/s but it was found that CTOA value kept constant value of about 13.2° until crack arrest irrespective of the crack velocity. These results showed the validation of the CTOA criterion for the high-pressure gas pipelines. The results also showed that CTOA in a burst test is generally different from that in a test using small-scale specimen. Future developments of the experimental procedure using a small-scale specimen to provide CTOA value corresponding with that in a burst test would be effective.

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On the Dynamic Gear Tooth Loading of Planetary Gearing as Affected by Bearing Clearances in High-Speed Machinery

Journal of Mechanisms Transmissions and Automation in Design ◽

10.1115/1.3260740 ◽

1985 ◽

Vol 107 (3) ◽

pp. 430-436 ◽

Cited By ~ 4

Author(s):

B. M. Bahgat ◽

M. O. M. Osman ◽

R. V. Dukkipati

Keyword(s):

High Speed ◽

Gear Tooth ◽

Contact Point ◽

Velocity Ratio ◽

Planetary Gear ◽

Spur Gears ◽

Governing Equations ◽

Contact Mode ◽

Gear Teeth ◽

Geometrical Constraints

The paper studies the effect of bearing clearances in the dynamic analysis of planetary gear mechanisms in high-speed machinery. For this purpose, an analytical model is developed based on the interdependence between kinematics and kinetic relationships that must be satisfied when contact is maintained between the journal and its bearing. The contact mode is formulated such that the bearing eccentricity vector must align itself with bearing normal force at the point of contact. The analysis mainly relies on determining the direction of the bearing eccentricity vector defined as the clearance angles βi at the bearing revolutes for each contact mode of the gear teeth. The governing equations of the clearance angles are developed using the geometrical constraints of the contact point location and the velocity ratio. The clearance angles and their derivatives are used to systematically evaluate kinematic and dynamic quantities. A rigid planetary spur gears with two revolute clearances is analyzed to illustrate the procedure.

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