| 摘要 |
PURPOSE:To improve the insulating efficiency at the end part of an aluminum sheet as well as to prevent the concentration of an electric field by a method wherein Alumite, which is an insulating material, is formed by oxidizing the end part of the aluminum sheet constituting a winding. CONSTITUTION:The surface of the part of an aluminum sheet 7, which constitutes a winding, is oxidized and Alumite (Al2O3)10 is formed. As the Alumite 10 formed on the end part of the aluminum sheet 7 is an excellent insulating material, the insulating efficiency of the end part of the aluminum sheet can be improved substantially. Also, as the other insulating material is not inserted, there is almost no increase in the cubic volume of the end part nof the aluminum sheet, and the generation of distortion on a winding when the winding is wound around can be prevented. Moreover, as all the protrusions at the end part of the aluminum sheet are formed into Alumite, no concentration of an electric field is generated, and the generation of a corona can be prevented effectively. |
