摘要 |
A screw is moved along an axis by a screw advancement-retraction mechanism. A screw rotation mechanism is supported for movement along the axis by a pair of supporting members, each includes a rail for use as a guide member. The supporting members are arranged individually along tie-bars for use as lateral members and extend parallel to the tie-bars. One longitudinal end portion of each supporting member is secured to a frame of an injection unit by a fixing portion including a fixing member. The other end portion of the supporting member is supported on each tie-bar by a movable portion including a sliding member. The sliding member is movable along an axis of the tie-bar. With this arrangement, deformation, if any, of the tie-bar is prevented from affecting the rail, so that the screw rotation mechanism and the screw can move steadily. |