| 摘要 |
PURPOSE:To obtain a braking mechanism, which actuates surely and is highly reliable over a long period of time by a structure wherein a ratchet mechanism, which checks the return rotation of the driving nut of a ball screw, which pushes a movable platen, is arranged on said driving nut. CONSTITUTION:When a mold clamping start signal is issued from a control device, a servo motor 10 is put into rotation so as to press a movable platen 5 through a ball screw 8 in order to perform mold clamping. When the movable platen 5 reaches the lock up position, the signal sent from a pressure sensor or position-detecting sensor puts an air cylinder 15 into drive through a controlling unit so as to engage a pawl 13 with a ratchet wheel 12. After that, the engagement between the pawl 13 and the ratchet wheel 12 is released by the air cylinder 15 through the mold opening command at the finished stage of injection, dwelling and cooling. Accordingly, the counterrotation of the driving nut 9 is made possible, resulting in performing the mold opening action by the servo motor 10. |
