INJECTION CYLINDER DEVICE OF DIE CASTING MACHINE

摘要

PROBLEM TO BE SOLVED: To restrain abrasion of a plunger tip and stabilize an injection action even if a thermal deformation is taken place on a plunger sleeve. SOLUTION: A rear end of a plunger rod 15 and a front end of an injection cylinder piston rod 19 are connected via a coupling 17. A rear end of the plunger rod 15 at the coupling 17 is elastically supported by a floating mechanism 39 in such a status where a clearance is formed between an inner peripheral face of the coupling 17. When a high temperature molten metal is injected from a molten metal injection port 11a, a plunger sleeve 11 is deformed and moved upwardly due to the temperature difference between upper and lower portions and, a plunger tip 13 is moved upward as well in compliance with the deformation. In accordance with the movement, a rear end of the plunger rod 15 is raised from downward and is floating upwardly so as to move by a clearance. Misalignment of the plunger sleeve 11 and the plunger rod 15 is thus corrected.