| 摘要 |
PURPOSE:To prevent molten aluminum from getting into an air hole, by a method wherein the air hole is closed by a mold having bars inserted into the air hole provided between slots, and wherein die-casting is performed. CONSTITUTION:A mold 4 inserted, at the time of aluminum die-casting, into an air hole provided between the slots of a rotor consists of bars 4a longer than the thickness of a laminated core by a specified value, and of a ring plate 4b fixing the bars. The mold 4 is fitted on a rotor core 1 so that the bars 4a may be inserted into the cooling air hole provided between the slots of the rotor core 1, and in this state, die-casting is performed. After die-casting is completed, the mold 4 is taken out of a die-cast squirrel-cage rotor. |
