| 摘要 |
PROBLEM TO BE SOLVED: To provide a technique which effectively preheats the whole of a runner including an intermediate stroke in a low pressure casting apparatus. SOLUTION: The preheating device 30 is equipped with: a die 18 provided with a runner 22 in the die introducing a molten metal 13 into a cavity 20; and a cylindrical sleeve 34 and a burner 32 facing to the opening part on the outside of the die of the runner in the die and preheating an intermediate stroke 16 introducing the molten metal 13 into the runner 22. The sleeve 34 separates a gap from the inner wall of the runner 22, and penetrates the runner 22. The burner 32 radiates flame from the side of the cavity 20 toward the inside of the sleeve 34. In the preheating device 30, by using the sleeve 34, a circulation between the intermediate stroke 16 and the cavity 20 can be made smooth. In this way, the amount of hot air made to flow into the intermediate stroke 16 can be increased, and the whole of the runner 26 including the intermediate stroke 16 can be effectively preheated. COPYRIGHT: (C)2011,JPO&INPIT |
