HUB FOR OPTICAL DISK AND ITS PRODUCTION

摘要

PURPOSE:To eliminate a junction part to which the stress is concentrated between a soft magnetic material and a thermoplastic resin and to obtain excellent productivity and reliability by dispersing a soft magnetic filler like a iron filler in the resin so that its density is higher on the side of a clamping magnet. CONSTITUTION:The soft magnetic material like the iron filler in the thermoplastic resin is dispersed to the clamp side with a high density by the difference of specific gravity between the thermoplastic resin and the soft magnetic material like the iron filler. Consequently, a unified hub 32 is obtained which is light and has a strong attraction to the clamp. When the soft magnetic filler is scaly and is oriented in parallel with the clamp surface, a close magnetic path is easy to form and a strong magnetic attraction is obtained. Thus, the junction part to which the stress is concentrated is eliminated between the soft magnetic material and the resin to obtain excellent productivity and reliability.