| 摘要 |
PROBLEM TO BE SOLVED: To prevent a synthetic resin from becoming uneven, and prevent the synthetic resin from becoming uneven due to a merging in order to prevent a deformation, a partial decrease of the strength, cracks, and an unfavorable bonding, etc., between an implanted article and the synthetic resin from generating due to the unevenness of the synthetic resin. SOLUTION: For this method, in a cavity formed into a shape to meet the outer shape of an impeller 10 wherein a counterbore part 26 is coaxially formed around the base end part 30a1 of a rotating shaft 30, the base part 30a of the rotating shaft 30 is located. Then, a molten resin is injected in the cavity through a gate in such a manner that the injection-molded body may be opened into a circular ring-shape, which is coaxial with the rotating shaft 30, on the peripheral edge part of the base end part 30a1 of the rotating shaft 30. After the synthetic resin is hardened, the impeller 10 is separated from a die, and the hardened synthetic resin is cut off at the gate of the die. On the peripheral edge part of a border with the outer peripheral surface of the base end part 30a1 of the rotating shaft 30 on the bottom surface of the counterbore part 26 of the impeller 10, a cut trace which protrudes upward into a circular ring-shape which is coaxial with the rotating shaft. 30, is provided. |
