| 摘要 |
PURPOSE:To prevent the humming sound by a method wherein a space as a source of producing the humming sound is freely filled up with a spacer made of thermo- restitutive resin which is heated during impregnating and drying processes. CONSTITUTION:Humming sound is produced by the vibration of a hum-proof belt 5 when there is a space between an iron core 3 and the belt 5. A spacer 7 is made of thermo-restitutive resin such as polyethylene resin, silicon resin, etc., and a space between the hum-proof belt 5 and the iron core 3 is filled up with resin, then the spacer 7 is heated at the temperature near a softening point. The resin spreads over the large or small residual space, and it is hardened after restitution, and free from deformation, so that it can fill up the space. As a result, humming is prevented without difficulty in processing as is often seen in press-boards, thus improving workability. |
