Controller for injection molding machine
AssigneeFanuc Corporation
InventorsTatsuhiro Uchiyama, Osamu Saito
Life of this patent
Estimating the term…
Abstract
There is provided the torque limiter for limiting a torque command to be output when pressure feedback control of the pressure holding step is performed. After the start of the pressure holding step, the torque limiter limits output torque of the servomotor for injection for a predetermined time period after the screw starts to move backward. As a result, the output torque in the backward direction of the screw is limited and reduced, whereby the speed of backward movement of the screw is reduced, and decrease of the pressure applied to the resin becomes moderate, thus abrupt drop of the pressure can be avoided.
Claims4
A controller for an injection molding machine that performs control of pressure in a pressure holding step by pressure feedback control, the controller comprising:
- torque limiting value setting means for setting, every cycle after the start of the pressure holding step, a torque limiting value in a direction opposite to a forward direction of a screw at the time of injection;
- and
- means for limiting the torque every cycle in accordance with the torque limiting value which are set in said torque limiting value setting means.
Dependencies are inferred from the claim text.