High Precision Control of Air Bubble Content in Working Oil

2020 Fiscal Year Final Research Report

• Project/Area Number: 18K03916
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 18040:Machine elements and tribology-related
• Research Institution: Hosei University
• Principal Investigator: Tanaka Yutaka 法政大学, デザイン工学部, 教授 (70179795)
• Co-Investigator(Kenkyū-buntansha): 坂間 清子 国立研究開発法人産業技術総合研究所, 情報・人間工学領域, 研究員 (70773539)
• Project Period (FY): 2018-04-01 – 2021-03-31
• Keywords: 気泡 / 作動油 / 油圧動力伝達システム / 油の剛性 / 気泡分離装置 / 旋回流

Outline of Final Research Achievements

Mixing of air bubbles in the hydraulic oil in hydraulic power transmission systems causes deterioration of the dynamic characteristics of the system, erosion of component, accelerated deterioration of the hydraulic oil, reduction of heat dissipation, and vibration noise. In this research, we proposed and developed a method for high precision control of air bubble content by a swirling flow of working oil. The amount of air bubbles in the oil flowing out of a bubble separation device is adjusted by controlling the opening and closing of the valve on a vent port of the device. The air bubble content from an output port of the bubble separation device was precisely controlled by the opening time of the vent valve. The validity of the proposed method was experimentally and numerically verified.

Free Research Field

機械要素設計

Academic Significance and Societal Importance of the Research Achievements

油圧動力伝達システムの作動油に気泡が混入すると油の剛性を低下させ，振動・騒音や機器破損の原因となる．しかし作動油中にどの程度の気泡量が含有すると機器の性能を損ない故障に至るかの定量的な指標は明らかとなっていない．これは現状では，作動油中の気泡含有量を実時間で精度よく測定したり，調整したりすることが極めて難しいためである．
申請者らが本研究で独自に開発した作動油中の気泡含有量を高精度で任意に調整できる手法を用いて，気泡を含む作動油が原因となる機器の劣化や故障に至る定量的な評価が可能となり，その社会的意義は大きい．