豊橋技術科学大: 開発比米粒還細小馬達

A few weeks ago the Mainichi News on-line reported the following:

豊橋技術科学大:米粒より小さいモーター

毎日新聞　2015年05月12日　21時27分（最終更新　05月12日　21時32分）

　豊橋技術科学大（愛知県豊橋市）は１２日、医療用機器や携帯電話などの実用レベルで使える「世界最小のマイクロ超音波モーター」を開発したと発表した。

　サイズは縦横それぞれ１．４ミリ、奥行き１ミリ。電気を通すと銅素材の穴の内部が、楕円（だえん）形に振動する。これに直径０．７ミリの金属棒を差すと回転する仕組みだ。

　加工が容易な銅素材の外側に、電圧をかけると素材が伸縮する「圧電素子」を貼り付けたシンプルな構造で、大量生産も容易という。

　開発にあたった真下智昭助教（３９）は「実用レベルに達していない先行開発された同じサイズのモーターに比べ、２００倍以上の力を出せる。今後は小型の内視鏡や携帯電話の振動装置などに活用できる」と話している。【吉富裕倫】

(試譯文)

On the 12th (May) Toyohashi University of Technology (Toyohashi city, Aichi) announced that they had developed "the world smallest micro ultrasonic motor" which could be used in practical level for medical treatment equipment and cellular phones.

  The size was 1.4 millimeters in height and width, 1 millimeter in depth. When electricity passed through, it vibrated in an oval shape inside a hole of the copper material. When a metal bar of 0.7 millimeters in diameter added to this, it became a system that could rotate.

  Outside the copper material it was stuck with elastic material "piezoelectric element" which capable of contracting and expanding when a voltage was applied. Because of its simple structure it was said that its mass production was easy.

Assistant Professor Tomoaki Mashita (39) who did the development was saying that "it is 200 times more powerful than the motor of the same size developed so far which does not reach the practical level. From now on it can be used in vibratory equipment including small endoscopes and cellular phones".

I think this is an important invention in the field of developing mini size equipment.