| 摘要 |
<p>An electro-mechanical drive apparatus uses a single motor and three one-way clutches to provide both injection and extruder functions in the injection unit of an injection molding machine. When engaged, the first one-way clutch couples the feed screw to the frame of the injection unit, the second clutch couples the drive motor to the feed screw, and the third clutch couples the drive motor to the ball screw mechanism. During rotation of the drive motor in a forward (injection) direction, (a) the third one-way clutch engages, rotating the ball screw mechanism which results in forward movement of the feed screw; (b) the second one-way clutch slips; and (c) the first one-way clutch engages to prevent rotation of the feed screw as it moves forward. When the drive motor is rotated in a reverse (extrusion) direction, (a) the second one-way clutch engages, rotating the feed screw, (b) the first one-way clutch slips, and (c) the third one-way clutch slips, allowing rotation of the ball screw mechanism commensurate with the rearward movement of the feed screw. Three versions of the drive apparatus, each having its own specific advantages, are disclosed: (I) a double shaft motor mounted adjacent separate drive couplings for extrusion (feed screw rotation) and injection (ball screw rotation-feed screw translation); (II) a single shaft motor connected by a mechanical coupling to a transmission that alternately drives the feed screw and ball screw; and (III) a hollow (or double) shaft motor axially aligned with the feed screw and ball screw mechanism, so that one rotor shaft is coupled to the feed screw and the shaft is coupled to the ball screw mechanism.</p> |
