| 摘要 |
<p>PURPOSE:To prevent the deformation or warp on the material at the process after the injection molding by specifying the volume ratio of the binder in the blank material for the core element. CONSTITUTION:The soft ferrite magnetic powder is combined with binder and is heat-treated and kneaded to be formed into slurry. At this time, the ratio of the binder is specified as 15-50vol%. Then, this blank material is pressed into the mold, and the core elements 1 and 2 having coil grooves 1a, 2a and coil lead-out grooves 1b, 2b are injection-molded. Then, the core elements are heated upto 300-500 deg.C for degreasing. Then, the core elements after the degreasing are sintered at the temperature 1,000-1,400 deg.C to provide the stator side core 1 and roter side core 2. For the cores 1 and 2 thus obtained, their degree of filling of the blank material in the mold is uniformized since the slurry-state blank material with superior fluidity has been injected into the mold, preventing deformation or warp in the process thereafter. Therefore, the surface machining thereof can be omitted after the sintering.</p> |
