| 摘要 |
PURPOSE:To very simply and inexpensively manufacture the phase plug by forming the it with synthetic resin blended with metallic powder, thereby equalizing the phase effectively. CONSTITUTION:A core A has an external shape of a gap 4 of a phase plug 1 and has a base A' used when the core is set in a metallic die X. Then the core A is set to the metallic die X. The base A' is inserted into a hole X2' of a lower die X2 and an upper die X1 is set in the lower die X2, then spaces 2', 3a'-3d' equivalent to a cone part 2 and truncated conical cylinders 3a-3d are formed in a cavity C. When the synthetic resin blended with metallic powder is injected from each gate (a) via a chamber Y, the spaces 2', 3a'-3d' are filled with the synthetic resin. After the synthetic resin is cured after lapse of a prescribed time, the upper die X1 and the lower die X2 are separated, and partly finished product having a resin rod a' equivalent to the gate a' and the core A is obtained. When the partly finished product is put into a molten metal whose melting point is more than that of the core A, the partly finished product is obtained and the phase plug 1 is obtained by removing the rod a'. |
