著者

井上 剛志 堀部 朋宏 内海 政春 安達 和彦

出版者

一般社団法人 ターボ機械協会

雑誌

ターボ機械 (ISSN:03858839)

巻号頁・発行日

vol.40, no.6, pp.359-369, 2012 (Released:2015-03-27)

参考文献数

11

被引用文献数

1

---

A finite-element model is derived for high-pressure fuel turbopump(HPFTP)rotor system. It considers the effects of gyro-moment, axial force and rotor dynamic fluid forces acting on the impellers, the inducer, the seal, and the turbine. The damped natural frequencies, real parts of eigenvalues, and mode shapes of the rotor system are analysed over the range of 0∼45,000rpm and the results are validated by comparing them with existing experimental data. The effects of gyro-moment, axial force and rotor dynamic fluid forces on the dynamical characteristics of the system are investigated. As a result, it is shown that axial force has a small effect and is considered negligible, wheareas gyro-moment and rotor dynamic fluid force have a relatively large effect on the dynamical characteristics of the rotor system. The frequency response curve of the unbalance response of HPFTP is also obtained using a numerical simulation and the results correspond to its actual vibration phenomenon.

著者

井上 剛志 高木 賢太郎 竹崎 勇輝 石川 昌義

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集C編 (ISSN:18848354)

巻号頁・発行日

vol.78, no.789, pp.1680-1690, 2012 (Released:2012-05-25)

参考文献数

7

---

The gyroscopic exercise tool which utilizes the gyroscopic effect caused by the whirling motion of the high speed rotating body to train the hand muscle is considered. This tool utilizes the contact phenomenon between the rotor and the case. When the input motion with 3-5 Hz is added to the case, the rotor spins in thousands rpm whirling with the precession motion which is synchronous to the input case motion. Conventional studies on this tool have assumed the continuous rolling motion of the rotor to the case. This paper does not set this assumption, and investigates the dynamical modeling of this tool considering the contact/non-contact conditions and the slip between the rotor and the case. Two kinds of motions are observed in the numerical simulation, one is the uniform precession which was observed in the conventional studies and the other is the periodically reverse precession. These two motions are physically explained, and are also observed in the experiment.

著者

三宅 牧人 桑田 真臣 穴井 智 辰巳 佳弘 井上 剛志 千原 良友 平尾 佳彦 藤本 清秀

出版者

日本泌尿器内視鏡学会

雑誌

Japanese Journal of Endourology (ISSN:21861889)

巻号頁・発行日

vol.27, no.2, pp.373-381, 2014 (Released:2014-11-07)

参考文献数

20

---

膀胱癌に対する5-アミノレブリン酸(5-ALA)を使用した蛍光膀胱鏡補助下経尿道的膀胱腫瘍切除術(TURBT)の診断精度および膀胱内再発予後の向上について検討した.膀胱癌96例を対象とし5-ALA溶液を経口または膀胱内投与し,白色光モードおよび赤色蛍光検出モードを切り替えながら膀胱内を観察した.採取した膀胱上皮組織の病理診断結果とモード別の画像所見から診断精度を評価した.白色光モードと比較して,蛍光検出モードでは特異度は低下したが(76.3% vs. 白色光84.6%),癌検出感度は向上した(84.5% vs. 白色光71.6%).蛍光膀胱鏡補助下TURBT症例と従来の白色光下TURBT症例をhistorical controlとして再発率を比較したが有意な差は認めなかった.蛍光膀胱鏡補助下TURBTは,診断薬5-ALAに起因する重篤な副作用もなく,癌の検出に有用で安全な手技であることが示されたが,治療成績については今後の多数例での前向き比較試験での評価も必要である.

著者

平手 知 井上 剛志

出版者

日本鉄道技術協会

雑誌

JREA (ISSN:04472322)

巻号頁・発行日

vol.62, no.12, pp.43633-43636, 2019-12

著者

中澤 輝彦 服部 治博 樽谷 一郎 安原 伸二 井上 剛志

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.84, no.862, pp.17-00543, 2018 (Released:2018-06-25)

参考文献数

20

被引用文献数

3

---

CVT chains have become widely used in vehicles because the slip between parts is very small, which enables efficient power transmission. However, the motion caused by the pins of the CVT chain entering and leaving the pulleys one after another during the power transmission process results in periodic motion of the whole chain. This behavior is known to affect noise and other basic performance aspects of CVTs. Therefore, it is important to study the geometrical specifications of the chain that affect periodic motion, such as the shape and dimensions of the parts. This study aimed to (1) identify the periodic motion that affects noise, and (2) formulate a motional theory to derive the ideal specifications of a CVT chain. First, after measuring the acceleration of the pulleys under conditions that generate large CVT noise, it was found that noise was greatly affected by periodic motion caused by the chordal action of the chain. Based on this result, a mathematical model was proposed to describe this chordal action. The pin profile curve was particularly considered in the model since it determines the motion of the chain at both ends of the chord part and has an important effect on the chordal action. Next, the chordal action of the chain was measured using an accelerometer, and the measured results were compared with the results calculated by the model. The results were consistent, which confirmed the validity of the model.

著者

加藤 潤也 藪井 将太 高木 賢太郎 井上 剛志

出版者

一般社団法人 日本機械学会

雑誌

日本機械学会論文集 (ISSN:21879761)

巻号頁・発行日

vol.84, no.861, pp.17-00227-17-00227, 2018 (Released:2018-05-25)

参考文献数

20

---

In design of rotating machines, analysis of external force is important for stable rotating operation. The various external forces such as unbalance force, seal contact force and rotor dynamic fluid force effect on the rotor system, dynamic characteristics of rotating system is changed by the external forces. The external force can vary depending on a rotor trajectory. In previous studies, a mathematical model of the dynamic characteristics had been formulated for small amplitude orbit around the equilibrium point for the rotor trajectory. However, the formulation hasn't been yet established in the rotor trajectory with large amplitude or eccentricity caused by the external forces. In this study, an experimental system using active magnetic bearing (AMB) is developed to achieve the formulation. The system can generate any arbitrary trajectory assuming various external forces and the rotor system follow the generated trajectory. The system can estimate the external force at the same time. Current flowing through coil of the AMB is controlled by a controller designed based on the frequency response to follow the arbitrary orbit. Then, the external forces are estimated from the control signal by the disturbance observer. Experiments were performed by assuming unbalance forces generated in the elastic rotor. From the results it was confirmed experimentally that high precision tracking control and estimation of external force are possible. The various rotor trajectory under the action of the external forces can be repeated by using the system, and the external force can be analyzed by the experimental data.