| 摘要 |
PROBLEM TO BE SOLVED: To improve the durability of a casting device by providing a gate to open in a disk part forming space on a lower center part of the disk part forming space, and feeding the molten metal from a lower part through the gate to make it difficult to degrade the device. SOLUTION: The inert gas is filled in a vehicle wheel forming space W through an inert gas nozzle 71, an inert gas control tank 70, and a stoke 31. The molten metal in a holding furnace 60 is pressurized and filled into the vehicle wheel forming space W through a molten metal feed pipe 62, the inert gas control tank 70 and the stoke 31. The molten metal is pressurized with the steep gradient from the stoke 31 to a gate 32, and when the feed of the molten metal into the vehicle wheel forming space W is started, the molten metal feed pressure becomes gentle in gradient. After the molten metal is again pressurized with the steep gradient, the specified pressure is maintained. Though the specified pressure after the molten metal feed is low, most of a rim part forming space R is located below the gate 32, then the gravity applied to the gate 32 is reduced. Thus, the molten metal feed pressure can be suppressed low, and a casting device becomes difficult to degrade. |
