| Project/Area Number |
03452119
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| Research Category |
Grant-in-Aid for General Scientific Research (B)
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| Allocation Type | Single-year Grants |
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| Research Field |
機械要素
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| Research Institution | SCIENCE UNIVERSITY OF TOKYO |
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Principal Investigator |
ANNO Yosiro SCIENCE UNIVERSITY OF TOKYO, PROFESSOR, 工学部, 教授 (40016209)
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| Co-Investigator(Kenkyū-buntansha) |
YOSHIMOTO Sigeka SCIENCE UNIVERSITY OF TOKYO, ASSOCIATE PROFESSOR, 工学部, 助教授 (80096718)
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| Project Period (FY) |
1991 – 1992
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| Project Status |
Completed (Fiscal Year 1992)
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| Budget Amount *help |
¥4,900,000 (Direct Cost: ¥4,900,000)
Fiscal Year 1992: ¥1,100,000 (Direct Cost: ¥1,100,000)
Fiscal Year 1991: ¥3,800,000 (Direct Cost: ¥3,800,000)
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| Keywords | Bearing / Water-Lubricated / Conical / Elastic Surface / Static Characteristics / 高速 |
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| Research Abstract |
Recently, higher rotational speed and higher accuracy have been strongly required in high speed spindles for drilling small holes on electric circuit board because diameters of small holes have been rapidly decreased. Further, these types of spindles are also required large radial load capacity in order to cut the edge of electric circuit boards. Until now, rolling bearings and aerostatic bearings have been often used for these kinds of high speed spindles. But the radial load capacity of aerostatic bearings are not large enough to apply them to cutting the boards and the rotational accuracies of rolling bearings are not sufficiently high in drilling very small holes. Therefore, it is necessary to develop a new type of bearing in order to overcome disadvantages of these bearings.
In this study, a new type of water-lubricated conical bearing is proposed for the high speed spindle. Water has advantages such as smaller viscosity than oil and cleanliness. In this bearing system, water is fed through a shaft and, therefore, water supply pressure at the outlet of the shaft is increased by the centrifugal force due to the shaft rotation. Further, since the bearing surface is coated by rubber, shallow pocket which increases the load capacity and de-creases the power consumption of the bearing is automatically caused in bearing clearance. In this study, static characteristics of the proposed bearing are investigated theoretically and experimentally. It was consequently confirmed that the proposed bearing could stably rotate till 120000rpm and was very useful for the high speed spindle.
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