Injection unit for an injection moulding machine
AssigneeSumitomo (SHI) Demag Plastics Machinery GmbH
InventorsOtto Grunitz, Simon Schulz
Life of this patent
Estimating the term…
Abstract
An injection unit for an injection molding machine includes a screw cylinder, a plasticizing screw which can be driven therein axially and rotatably, the drive unit of which has an electric drive motor, a spindle drive coupled to the screw for the axial movement of the screw, and a rotary drive arranged coaxially with the spindle drive and allowing an axial displacement of the screw for the rotational movement of the screw. A differential gearing, is arranged between the drive motor, on the one hand, and spindle drive and rotary drive, on the other hand, with a differential cage, two driven gears and at least one compensating gear in between.
Claims10
An injection unit for an injection moulding machine, comprising:
- a screw cylinder (1);
- a plasticizing screw (2) which can be driven therein axially and rotatably,
- the drive unit (3) of which has an electric drive motor (4),
- a drive assembly comprising a spindle drive (5) coupled to the screw (2) for the axial movement of the screw (2), and a rotary drive (6) arranged coaxially with the spindle drive (5) and allowing an axial displacement of the screw (2) for the rotational movement of the screw (2);
- a differential gearing (7), which is arranged between the drive motor (4) and the drive assembly, said differential gearing (7) having a differential cage (8), two driven gears (11, 12) and at least one compensating gear (19, 20) in between,
- wherein the drive motor (4) is drive-coupled to the differential cage (8),
- wherein one driven gear (11) of the differential gearing (7) is output-coupled to the spindle nut (14) of the spindle drive (5),
- wherein the other driven gear (12) of the differential gearing (7) is output-coupled to the rotary drive (6) of the screw (2),
- wherein the driven gears (11, 12) or the downstream spindle nut (14) and rotary drive (6) can be loaded by a respective controllable spindle brake and rotary brake (21, 22), and
- wherein the functional movements of the screw (2) can be controlled by a matched intervention of the spindle brake (21) on the spindle nut (14) and rotary brake (22) on the rotary drive (6).
Dependencies are inferred from the claim text.