Abstract
Externally pressurized gas journal bearings with an asymmetric gas supply mechanism have been developed by authors. This bearing has a large load capacity compared with conventional symmetric gas supply bearings because low and high pressurized gases are supplied to loaded and counter-loaded side bearing surfaces, respectively. It has been proposed that this type of bearing has advantageous characteristics applicable for use in a general purpose X-ray computed tomography scanner gantries. The adaptation of this gas bearing to the device can conceivably contribute to an improved performance by increasing the rotational speed and decreasing the operating noise. This is effective for higher precision scanning and for reduction of the level of stress on a patient. Numerical calculations of this bearing were conducted and the resulting characteristics were compared with those of a conventional symmetric supply gas journal bearing. The effectiveness of the bearing for this application was demonstrated by conducting rotation tests using a small size test rig. The rotor generates centrifugal force by the rotation. The bearing diameter and length were 60 and 120 mm, respectively. The test bearing was operated under several supply gas pressure controlled conditions. The rotor vibration amplitude can be decreased by supply pressure control under generating the centrifugal force condition. The amplitude increased under conventional symmetric gas supply conditions with an increase in rotational frequency. Therefore, effectiveness and safeness of the bearing was experimentally verified. The gas flow rate decreased under controlled supply pressure conditions compared with conventional supply pressure conditions.
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References
Ise T, Miyatake H, Asami T (2012) Hydrostatic asymmetric journal gas bearings for large load rotors. J Adv Mech Des Syst Manuf 6(1):149–157
Ise T (2011) Fluid bearing with asymmetric fluid supply system. Japanese patent publication number 2011–099459. (In Japanese)
Kumazawa M, Kunitomo T, Yokoyama Y, Nakajima T, Tsuruga K (2000) ACROSS: theoretical and technical developments and prospect to future applications. JNC Tech Rev 9:115–129. (In Japanese with English abstract)
Ikuta R, Yamaoka K, Miyakawa K, Kunitomo T, Kumazawa M (2002) Continuous monitoring of propagation velocity of seismic wave using ACROSS. Geophys Res Lett 29(13):1029/2001GL013974
Yamaoka K, Kunitomo T, Miyakawa K, Kobayashi K, Kumazawa M (2001) A trial for monitoring temporal variation of seismic velocity using an ACROSS system. I Arc 10:336–347
Okano M (2006) Asymmetric fluid bearing. Japanese patent publication number 2006–207668. (In Japanese)
Ise T et al, Torii T, Morita N, Togo S, Okano M (2007) Hydrostatic asymmetric journal gas bearings for largely unbalanced rotors of seismic ACROSS transmitters. J Adv Mech Des Syst Manuf 1(1):93–101
Ise T, Torii T, Morita N, Kunitomo T, Togo S, Okano M (2010) Design and workout of ACROSS transmitters using air bearings, active geophysical monitoring. Handb Geophys Explor Seismic Explor 40:193–209
Ise T et al, Torii T, Morita N, Togo S, Okano M (2007) Hydrostatic asymmetric journal gas barings for seismic ACROSS transmitters. J Adv Mech Des Syst Manuf 1(5):681–689
Tokumiya T, Ishikawa T, Takada N, Ise T (2013) Active rotation balancing mechanism of the X-ray CT gantry. Japanese patent application number 2013–160317. (In Japanese)
Yoshimoto S (1986) Static characteristics of an aerostatic journal bearing with partially gas-fed slot restrictors: on the double-row admission bearing using feeding slits. Bull JSME 29(252):1907–1912
Kaneko R (1974) Numerical analysis in fluid film lubrication. Lubrication 20(12):883–889. (In Japanese)
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Ise, T. et al. (2015). Externally Pressurized Gas Journal Bearings with Asymmetric Gas Supply (Verification of Availability of Gas Pressure Control Using a Small Size Test Rig). In: Pennacchi, P. (eds) Proceedings of the 9th IFToMM International Conference on Rotor Dynamics. Mechanisms and Machine Science, vol 21. Springer, Cham. https://doi.org/10.1007/978-3-319-06590-8_105
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DOI: https://doi.org/10.1007/978-3-319-06590-8_105
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