ELECTRIC SUPERCHARGER

To efficiently cool a coil of an electric motor.SOLUTION: A plurality of first oil supply holes 61 are formed in a peripheral wall 12b with openings on the first coil end 23a side of the first oil supply holes 61 being arranged side by side in the peripheral direction of a rotary shaft 17. A plurality of second oil supply holes 62 are formed in the peripheral wall 12b with openings on the second coil end 23b side of the second oil supply holes 62 being arranged side by side in the peripheral direction of the rotary shaft 17. For example, even when a whole electric supercharger 10 is inclined, oil flowing from the plurality of first oil supply holes 61 to the first coil end 23a hardly flows unevenly to one side in the peripheral direction of the rotary shaft 17, compared to the case that only one first oil supply hole 61 is formed in the peripheral wall 12b, and oil flowing from the plurality of second oil supply holes 62 to the second coil end 23b also hardly flows unevenly to one side in the peripheral direction of the rotary shaft 17, compared to the case that only one second oil supply hole 62 is formed in the peripheral wall 12b.SELECTED DRAWING: Figure 7 【課題】電動モータのコイルを効率良く冷却すること。【解決手段】第１油供給孔６１は、第１油供給孔６１における第１コイルエンド２３ａ側の開口が回転軸１７の周方向に並んで配置された状態で周壁１２ｂに複数形成されている。第２油供給孔６２は、第２油供給孔６２における第２コイルエンド２３ｂ側の開口が回転軸１７の周方向に並んで配置された状態で周壁１２ｂに複数形成されている。例えば、電動過給機１０全体が傾いたとしても、周壁１２ｂに形成されている第１油供給孔６１が１つだけの場合に比べると、複数の第１油供給孔６１から第１コイルエンド２３ａに向けて流れるオイルが回転軸１７の周方向の一方に偏って流れ難くなる。また、周壁１２ｂに形成されている第２油供給孔６２が１つだけの場合に比べると、複数の第２油供給孔６２から第２コイルエンド２３ｂに向けて流れるオイルが回転軸１７の周方向の一方に偏って流れ難くなる。【選択図】図７