摘要 |
A die casting machine provided with an electric servomotor and a hydraulic cylinder as drive sources for injection is enhanced in operation stability in an injection step. In the injection step, the rotational speed of an injection electric servomotor (3) is pattern-controlled to follow a preset speed command pattern while the forward speed of a piston (5a) caused by driving of an injection hydraulic cylinder (5) is feedback-controlled with an addition signal of the forward speed of the piston (5a) caused by driving of the injection electric servomotor (3) and the forward speed of the piston (5a) caused by driving of the injection hydraulic cylinder (5). Alternatively, the forward speed of the piston (5a) caused by driving of the injection hydraulic cylinder (5) may be pattern-controlled to follow a preset speed command pattern while the rotational speed of the injection electric servomotor (3) is feedback-controlled with the addition signal. |