kunststoffspritzgiessmaschine with rotational and linear drive

摘要

The plastic injection moulding machine has an injection cylinder with screw, which takes power for both linear and rotary motion, from a single motor. In the novel arrangement, the drive motor (41) is a servomotor. An hydraulic cylinder (24, 26) provides linear motion, connected (22, 23) in closed circuit with a pump (21). The screw (14) drive shaft (15) is rotated by the motor (31), and corresponds with the piston rod (25). The motor has supply- (32) and return- (33) lines connected to a flow line (22), which includes a controllable non-return valve (nrv) (63), operated by a two-way valve (66). Pref. in the line (23) connecting the cylinder (26) of the linear drive to the pump, there is an nrv (61). During hydraulic rotary drive, the nrv (61) is connected directly via the flow line (67) to the return line (33). A proportional pressure valve (71) is connected to the cylinder (26) of the linear valve. The linear drive has at least one equal piston cylinder unit (24, 26), i.e. a double acting piston unit with equal working areas. The piston cylinder unit is connected by a yoke (17) or its counterpart (18) with the injection cylinder (11) and also to the drive shaft (15) on the screw side. Between the motor drive shaft (34) and the piston rod (25) there is a coupling (52).