| 摘要 |
PURPOSE:To prevent the deterioration of magnetic characteristics of an iron core and increase its insulation by giving powder coating to the iron core after applying to it immersion treatment in varnish. CONSTITUTION:Before the process of immersing an iron core in a powder resin, it is applied a varnish immersion. Shrinkage of varnish during hardening is small and the amount of varnish that permeates into the iron is also small. Therefore, the strain developed in the iron core by shrinkage stress in the hardening of the varnish can be neglected, and the deterioration of magnetic characteristics is extremely small. After the immersion the iron core is moved in the vanish around, then the whole of the iron core is coated with powder resin. In this coating the varnish film absorbs the shrinkage stress by the powder resin in its hardening, making it possible to suppress the transmission of the shrinkage stress to the iron core body to a very small extent. Accordingly, thickness of the powder resin coating can be made thick, and insulation can be improved, and further deterioration of magnetic characteristics of the iron core can be prevented. |
