| 摘要 |
PURPOSE:To contrive to lighten the weight and to remarkably lower the inertial force and realize the improvement of the responsiveness, rapidity, stability, preciseness and reproducibility by a structure wherein a screw driving part is constituted by providing an outer tubular shaft, on the outer periphery of which a ball screw mechanism is provided, and an inner shaft, which pivotally inserted in the outer shaft. CONSTITUTION:Due to the normal rotation of a servo motor 27, the turning force of said motor 27 is transmitted through a course of a driving gear 28 a driven bear 25 a spline mechanism 24 an inner shaft 3 a coupling member 17 a screw 6. As a result, the screw rotates normally so as to be allowed to meter molten resin material. Further, by rotating the servo motor 27 in reverse direction, the screw 6 can be rotated reversely through the same course as described above. On the other hand, due to the normal rotation of a servo motor 22, the turning force of said motor 22 is transmitted through a course of a driving gear 23 a driven gear 20 an outer shaft 2 a ball screw mechanism 5 a sliding member 16 the coupling member 17. As a result, the screw 6 is advanced, resulting in allowing to inject the metered molten resin material in order to fill a mold. Furthermore, by rotating the servo motor 22 in reverse direction, the screw 6 can be retreated through the same course as described above. |
