| 摘要 |
PROBLEM TO BE SOLVED: To maintain a temperature of a metal raw material of one shot of injecting suitably in a heating cylinder without enhancing capability of a heater by changing a temperature of the material before charging to meet that at a charging time when charging the material of the one shot in the cylinder. SOLUTION: A screw 1 of a metal injection molding machine is rotatably and longitudinally movably contained in a heating cylinder 7, and a raw material heater 12 having a raw material preheating cylinder 5 is installed above a feeder 6 mounted at a raw material inlet 3 of the cylinder 1. The heater 12 has two heating control zones above and below, and preheating heaters 10A, 10B and a temperature detector 11 are provided in the respective zones. A metal material 2 before charging in the cylinder 7 is supplied by each one shot of injecting to the cylinder 5, and preheated at each one shot in the cylinder 5. In this case, the charged amounts of each one shot are not uniformly heated, but controlled to change the heating temperature according to a charging time.
|
