Injection unit for a plastic injection moulding machine

An injection unit for a plastic injection molding machine, comprising:

• a screw (16),
• a motion spindle (10) as a first drive element, via which the screw (16) can be rotationally driven for the plasticization and is movable in the axial direction for the injection,
• a spindle nut (30) as second drive element, which is coupled to the motion spindle (10) via a motion screw thread (13),
• a large electric motor (20) which is arranged so as to be fixed to the frame and by which, while one drive element (10, 30) is held against rotation, the other drive element (30, 10) can be rotationally driven for moving the screw (16) during the injection, and
• a device (35, 40) which is arranged so as to be fixed to the frame and by which a rotational speed of the one drive element (10, 30) can be preset during the plasticization, said rotational speed being different from rotational speed at which the large electric motor (20) simultaneously drives the other drive element (30, 10), wherein
• the drive element (10, 30) held against rotation during the moving of the screw (16) for the injection is lockable by a releasable mechanical brake (40);
• wherein the spindle nut (30) is rotationally drivable by the large electric motor (20), by which the screw (16) is movable during the injection, and the motion spindle (10) is lockable against rotation by the brake (40);
• and
• wherein a first clutch (60) which is effective for rotating the screw (16) during the plasticization is arranged between the motion spindle (10) and the large electric motor (20), and a second clutch (62) which is effective for moving the screw (16) during the injection is arranged between the spindle nut (30) and the large electric motor (20).

An injection unit for a plastic injection molding machine, comprising:

• a screw (16),
• a motion spindle (10) as a first drive element, via which the screw (16) can be rotationally driven for the plasticization and is movable in the axial direction for the injection,
• a spindle nut (30) as second drive element, which is coupled to the motion spindle (10) via a motion screw thread (13),
• a large electric motor (20) which is arranged so as to be fixed to the frame and by which, while one drive element (10, 30) is held against rotation, the other drive element (30, 10) can be rotationally driven for moving the screw (16) during the injection, and
• a device (35, 40) which is arranged so as to be fixed to the frame and by which a rotational speed of the one drive element (10, 30) can be preset during the plasticization, said rotational speed being different from rotational speed at which the large electric motor (20) simultaneously drives the other drive element (30, 10), wherein
• the drive element (10, 30) held against rotation during the moving of the screw (16) for the injection is lockable by a releasable mechanical brake (40);
• wherein the spindle nut (30) is rotationally drivable by the large electric motor (20), by which the screw (16) is movable during the injection, and the motion spindle (10) is lockable against rotation by the brake (40),
• wherein the rotational speed of the spindle nut (30) is presetable by the device (35, 40),
• wherein the large electric motor (20) is connected to the motion spindle (10) via a sliding pair (15, 22), the spindle nut (30) is lockable against rotation by the brake (40), and the large electric motor (20) drives the motion spindle (10) for the plasticization when the brake (40) is released and when the spindle nut (30) is driven by the second electric motor (35) and for injection of plastic when the spindle nut (30) is locked by the brake (40),
• wherein a rotational movement of the motion spindle (10) is transmitable to the screw (16) via a clutch (45, 52), and
• wherein one clutch (48, 60, 62) is an externally operated clutch which is operated between the plasticization and the injection.

An injection unit for a plastic injection molding machine, comprising:

• a screw (16),
• a motion spindle (10) as a first drive element, via which the screw (16) can be rotationally driven for the plasticization and is movable in the axial direction for the injection,
• a spindle nut (30) as second drive element, which is coupled to the motion spindle (10) via a motion screw thread (13),
• a large electric motor (20) which is arranged so as to be fixed to the frame and by which, while one drive element (10, 30) is held against rotation, the other drive element (30, 10) can be rotationally driven for moving the screw (16) during the injection, and
• a device (35, 40) which is arranged so as to be fixed to the frame and by which a rotational speed of the one drive element (10, 30) can be preset during the plasticization, said rotational speed being different from rotational speed at which the large electric motor (20) simultaneously drives the other drive element (30, 10), wherein
• the drive element (10, 30) held against rotation during the moving of the screw (16) for the injection is lockable by a releasable mechanical brake (40);
• wherein the spindle nut (30) is rotationally drivable by the large electric motor (20), by which the screw (16) is movable during the injection, and the motion spindle (10) is lockable against rotation by the brake (40),
• wherein the rotational speed of the spindle nut (30) is presetable by the device (35, 40),
• wherein the large electric motor (20) is connected to the motion spindle (10) via a sliding pair (15, 22), the spindle nut (30) is lockable against rotation by the brake (40), and the large electric motor (20) drives the motion spindle (10) for the plasticization when the brake (40) is released and when the spindle nut (30) is driven by the second electric motor (35) and for injection of plastic when the spindle nut (30) is locked by the brake (40),
• wherein a rotational movement of the motion spindle (10) is transmitable to the screw (16) via a clutch (45, 52), and
• wherein one clutch (52) is a one-way clutch, and by the large electric motor (20), one drive element (10) is drivable in one direction of rotation for the plasticization and in the other direction of rotation for the injection.

An injection unit for a plastic injection molding machine, comprising:

• a screw (16),
• a motion spindle (10) as a first drive element, via which the screw (16) can be rotationally driven for the plasticization and is movable in the axial direction for the injection,
• a spindle nut (30) as second drive element, which is coupled to the motion spindle (10) via a motion screw thread (13),
• a large motor (20) which is arranged so as to be fixed to the frame and by which, while one drive element (10, 30) is held against rotation, the other drive element (30, 10) can be rotationally driven for moving the screw (16) during the injection, and
• a device (35, 40) which is arranged so as to be fixed to the frame and by which a rotational speed of the one drive element (10, 30) can be preset during the plasticization, said rotational speed being different from rotational speed at which the large electric motor (20) simultaneously drives the other drive element (30, 10), wherein
• the drive element (10, 30) held against rotation during the moving of the screw (16) for the injection is lockable by a releasable mechanical brake (40);
• wherein the spindle nut (30) is rotationally drivable by the large electric motor (20), by which the screw (16) is movable during the injection, and the motion spindle (10) is lockable against rotation by the brake (40);
• and
• wherein the second electric motor (35) is connected to the motion spindle (10) via a sliding pair, a drive element (55) in kinematic chain between the second electric motor (35) and the sliding pair is lockable against rotation by the brake (40), and for the plasticization, the second electric motor (35) drives the motion spindle (10) when the brake (40) is released and when the spindle nut (30) is driven by the first electric motor (20), and, for the injection of plastic, the first electric motor (20) drives the spindle nut (30) when the motion spindle (10) is locked against rotation by the brake (40).

An injection unit for a plastic injection molding machine, comprising:

• a screw (16), and a motion spindle (10) connectable directly to the screw and being coaxial with the screw, the motion spindle (10) serving as a first drive element to rotate the screw for the plasticization and being movable in the axial direction for the injection,
• a spindle nut (30) as second drive element, which is coupled to the motion spindle (10) via a motion screw thread (13),
• a large electric motor (20), which is arranged so as to be fixed to a frame of the machine and by which, while one of the drive elements (10, 30) is held against rotation, the other drive element (30, 10) can be rotationally driven for moving the screw (16) during the injection, and
• a device (35, 40) which is arranged so as to be fixed to the frame and by which a rotational speed of the one drive element (10, 30) can be preset during the plasticization, said rotational speed being different from a rotational speed at which the large electric motor (20) simultaneously drives the other drive element (30, 10), wherein
• the drive element (10, 30) held against rotation during the moving of the screw (16) for the injection is lockable by a releasable mechanical brake (40), and
• wherein a first clutch (60) which is effective for rotating the screw (16) during the plasticization is arranged between the motion spindle (10) and the large electric motor (20), and a second clutch (62) which is effective for moving the screw (16) during the injection is arranged between the spindle nut (30) and the large electric motor (20).