INJECTION ARRANGEMENT FOR A MOULDING MACHINE AND METHOD FOR OPERATING THE SAME

Abstract

An injection arrangement for a moulding machine includes a moulding compound reservoir and an injection unit. The moulding compound reservoir is configured to provide a plasticized mass and to push out the plasticized mass through a discharge opening, and a connecting device is coupled to the discharge opening of the moulding compound reservoir and a feed opening of the injection unit, and is configured to direct the plasticized mass from the moulding compound reservoir to the injection unit. The connecting device includes an articulated element, and a relative movement between the moulding compound reservoir and the injection unit can be performed with the articulated element.

Claims

1. An injection arrangement for a moulding machine having a moulding compound reservoir and an injection unit, wherein the moulding compound reservoir is configured to provide a plasticized mass and to push out the plasticized mass through a discharge opening, and a connecting device is coupled to the discharge opening of the moulding compound reservoir and a feed opening of the injection unit and is configured to direct the plasticized mass from the moulding compound reservoir to the injection unit, wherein the connecting device comprises at least one articulated element, wherein, with the at least one articulated element, a relative movement between the moulding compound reservoir and the injection unit can be performed.

2. The injection arrangement according to claim 1, wherein the moulding compound reservoir is configured as at least one plasticizing unit, which preferably comprises at least one plasticizing screw and/or at least one extruder screw.

3. The injection arrangement according to claim 1, wherein the injection unit comprises at least one plasticizing screw and/or one injection cylinder.

4. The injection arrangement according to claim 1, wherein the injection unit is mounted in a manner linearly displaceable along a longitudinal axis.

5. The injection arrangement according to claim 1, wherein the injection unit comprises a drive mechanism—preferably formed by at least one piston-cylinder unit and/or at least one spindle drive.

6. The injection arrangement according to claim 1, wherein the moulding compound reservoir is mounted in a stationary manner.

7. The injection arrangement according to claim 1, wherein the connecting device connects the discharge opening of the moulding compound reservoir, and the injection unit shielded from a environment—preferably in an airtight manner.

8. The injection arrangement according to claim 1, wherein the connecting device, at least some sections of it, is configured in a tubular manner.

9. The injection arrangement according to claim 1, wherein the moulding compound reservoir and/or the connecting device comprise a degassing device.

10. The injection arrangement according to claim 1, wherein the connecting device is configured with a variable length.

11. The injection arrangement according to claim 10, wherein the connecting device comprises a telescoping section.

12. The injection arrangement according to claim 1, wherein the connecting device comprises two articulated elements.

13. The injection arrangement according to claim 1, wherein the at least one articulated element is configured as a ball joint.

14. The injection arrangement according to claim 1, wherein the at least one articulated element is configured as a flexure bearing.

15. The injection arrangement according to claim 1, wherein the moulding compound reservoir comprises a recycling device.

16. A moulding machine with the injection arrangement according to claim 1.

17. A method for operating the injection arrangement according to claim 1, wherein with the help of a moulding compound reservoir, a plasticized mass is provided by pushing out the plasticized mass through a discharge opening, and a connecting device passes on the plasticized mass from the moulding compound reservoir to the injection unit, wherein, with at least one articulated element of the connecting device, a relative movement between the moulding compound reservoir and the injection unit is compensated.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Further details and embodiments of the invention are apparent from the figures as well as the associated description of the figures. In that:

[0051] FIG. 1 illustrates a first embodiment of an injection arrangement according to the invention,

[0052] FIG. 2 illustrates a first embodiment of an articulated element,

[0053] FIG. 3 illustrates a second embodiment of an articulated element,

[0054] FIG. 4 illustrates a schematic representation of a ball joint,

[0055] FIG. 5 is a detailed view for FIG. 2, 3, or 4,

[0056] FIG. 6 illustrates a third embodiment of an articulated element,

[0057] FIG. 7 illustrates a further embodiment of an articulated element,

[0058] FIG. 8 illustrates a fifth embodiment of an articulated element, and

[0059] FIG. 9 illustrates a sixth embodiment of an articulated element.

DETAILED DESCRIPTION OF THE INVENTION

[0060] FIG. 1 illustrates a first embodiment of an injection arrangement 1 according to the invention. The injection arrangement comprises a moulding compound reservoir 2 and an injection unit 3.

[0061] The moulding compound reservoir 2 is formed by an extruder screw 8, which is driven via the rotational drive 12.

[0062] The extruder screw 8 extrudes a material, which is fed into it via the filling funnel 13, and continuously pushes out the plasticized mass via the discharge opening 4. Via the connecting device 5, the plasticized mass reaches the feed opening 15 of the injection unit 3.

[0063] In this embodiment, the injection unit 3 is shown by the plasticizing screw 7, which further plasticizes the plasticized mass fed from the moulding compound reservoir 2 and injects it into a moulding tool via an injection nozzle 10.

[0064] The plasticizing screw 7 can be rotationally driven via a rotational drive 11 and can be displaced along the longitudinal axis 9 of the injection unit 3 by a linear drive, which is not illustrated in this figure for reasons of clarity.

[0065] A linear drive of a plasticizing screw 7 can, for example, be executed as a piston-cylinder unit or a spindle drive.

[0066] As schematically indicated in this figure, the moulding compound reservoir 2 is mounted in a statical manner (represented by the fixed bearings) and the injection unit 3 is mounted in a linearly displaceable manner (represented by the floating bearings).

[0067] The connecting device 5, here represented in a tube-like manner, comprises two articulated elements 6, which enable the injection unit 3 to perform a relative movement to the moulding compound reservoir 2.

[0068] With very small, linear relative movements between the injection unit 3 and the moulding compound reservoir 2, the required variation in length of the connecting device 5 can be managed with an elastic deformation of the same.

[0069] If the relative movement becomes larger, it may be required to compensate the variation in length between the two articulated elements 6—for example, by a telescoping section—so that no damages of the connecting device 5 occur.

[0070] Furthermore, a filter unit 14 is provided in the connecting device 5, which can remove larger particles from the plasticized mass coming from the moulding compound reservoir 2.

[0071] It can be provided that the connecting device 5 comprises a degassing device or is connected to such a device, wherein undesired gases can be sucked off from the plasticized mass.

[0072] Preferably it can be provided that the connecting device 5 is arranged in such a way that the plasticized mass from the moulding compound reservoir 2 falls into the injection unit 3 by the force of gravity and that the connecting device 5 surrounds the falling plasticized mass in a contact-free manner.

[0073] This can be achieved, for example, with a connecting device 5 configured in a perpendicular tubular manner.

[0074] FIG. 2 illustrates a first embodiment of an articulated element 6 for a connecting device 5 of an injection arrangement 1 according to the invention.

[0075] The connecting device 5 of this embodiment is formed by a tube, more precisely, by a divided tube, which comprises a first part 16 of the connecting device 5 and a second part 17 of the connecting device 5.

[0076] The first part 16 and the second part 17 are connected with one another via the articulated element 6, wherein the endpiece of the first part 16 is configured with a spherical section 20.

[0077] The second part 17 rests against the spherically formed end of the first part 16, more precisely, its outer surface, via the gasket 19 or it is braced therewith via bolts 18.

[0078] The bolts 18 of this embodiment can be formed, for example, by standard-conforming bolts. By screwing in these bolts 18, the second part 17 is braced with the first part 16, wherein the gasket 19 between the first part 16 and the second part 17 is braced/pressed-on and seals off the interior of the tubes (in other words, shields it from the environment).

[0079] With a relative movement of the first part 16 to the second part 17, the gasket 19 at the spherical section 20 is displaced, and a relative movement of the tubes to one another is permitted without damaging.

[0080] FIG. 3 illustrates a second embodiment of an articulated element 6, wherein the functionality of the embodiment of FIG. 3 corresponds to that of FIG. 2.

[0081] However, in FIG. 3, in contrast to FIG. 2, the bolt 18 executed as a piston rod element of a hydraulic device, wherein the parts 16, 17 can be braced with one another and released from one another in a hydraulic manner.

[0082] This results in the substantial advantage, that the bracing can be released upon a movement of part 16 relative to part 17, in order to permit the movement with a lower resistance (caused by friction) to avoid increased wear of the gasket.

[0083] Thus, for example, it can be provided that prior to a relative movement of the injection unit 3 to the moulding compound reservoir 2 the braced parts 16, 17 are released, and once the movement has been performed, the tensioning of the first part 16 with the second part 17 using the bolt 18 is re-established via the hydraulic element.

[0084] FIG. 4 illustrates a schematic representation of the already explained embodiments of FIG. 2 or 3, wherein it is indicated that, via a bolt connection, a first part 16 can be braced with a second part 17 of the connecting device 5, wherein, via a spherical section 20, a movement of the parts 16, 17 relative to one another is permitted. Such a joint structure is also being referred to as a ball joint.

[0085] FIG. 5 illustrates a detailed view for FIG. 2, 3, or 4, wherein the detail of the gasket 19 is represented enlarged.

[0086] It is very easy to recognise, how, due to the tensioning of the first part 16 with the second part 17 with the bolt 18, a force acts on the gasket from four opposite directions, wherein an approximately hydrostatic load of the gasket can occur, resulting in particularly favourable sealing conditions and wear conditions.

[0087] FIG. 6 illustrates a third embodiment of an articulated element 6 of a connecting device 5, wherein in the embodiment of FIG. 6, the articulated element 6 is directly coupled to the injection unit 3. The injection unit 3 can be recognised as the cylinder of a plasticizing screw 7.

[0088] In this embodiment, the connecting device 5 comprises a tube-like connection, which, via the guide element 21, is guided in a retaining element 22 fastened to the injection unit 3.

[0089] The feed opening 15 of the injection unit 3 executed as an oblong hole, to which the connecting device 5, configured in a tubular manner, is guided via the retaining element 22 and the guide element 21.

[0090] The guide element 21 is bolted to the injection unit 3.

[0091] The linear freedom of movement of the connecting device 5 along the injection unit 3 is indicated by the arrow.

[0092] FIG. 7 illustrates a further embodiment of an articulated element 6 of a connecting device 5 for an injection arrangement 1, wherein a first part 16 and a second part 17, which both are formed by tubes, are connected with one another via a flexure bearing.

[0093] The flexure bearing is formed by the two elastic washers 23, which are connected with one another via the connecting disc 24.

[0094] The two elastic washers 23 can permit an increased elastic deformation due to their shape, which can be additionally supported by a suitable choice of material. A suitable material for an increased elastic deformability would be rubber, for example.

[0095] With the rotationally symmetric design of this flexure bearing, which is shown by FIG. 7, a tilting or relative movement of the first part 16 to the second part 17 in all spatial directions is possible, too.

[0096] Furthermore, with the elastic washers 23, a relative movement of the first part 16 to the second part 17—even though only small—linearly along the axis of symmetry of the parts 16 and 17 is admissible, too.

[0097] The opening 27 shown on the left-hand side of this embodiment can be used to connect a degassing device to the connecting device 5, wherein undesired gases can be sucked off from the connecting device 5 via the opening 27. Such a degassing device can be configured as a vacuum suction device, for example.

[0098] FIG. 8 illustrates a fifth embodiment of an articulated element 6 of a connecting device 5 for an injection arrangement 1.

[0099] In this embodiment, the two tube elements (the first part 16 and the second part 17 of the connecting device 5) are connected with one another via the flange 25. More precisely, they are bolted to one another, wherein the interior of the tubes is shielded from the environment with the gasket 19.

[0100] With the flange 25, a rotation around the centre axis is permitted, wherein the first part 16 and the second part 17 can rotate relative to one another.

[0101] FIG. 9 illustrates a sixth embodiment of an articulated element 6 for a connecting device 5 of an injection arrangement 1.

[0102] Here, a first tubular part 16 of the connecting device 5 is connected with a second part 17 of the connecting device 5 via a flange 25 by means of a clamping element 26.

[0103] The flange 25 is arranged at the first part 16. A clamping device 26, which is arranged at the second part 17, can be inserted into the flange 25 via a hook and can be braced via an actuation lever.

LIST OF REFERENCE SIGNS

[0104] 1 Injection arrangement [0105] 2 Moulding compound reservoir [0106] 3 Injection unit [0107] 4 Discharge opening [0108] 5 Connecting device [0109] 6 Articulated element [0110] 7 Plasticizing screw [0111] 8 Extruder screw [0112] 9 Longitudinal axis of the injection unit [0113] 10 Injection nozzle [0114] 11 Rotational drive of the injection unit [0115] 12 Rotational drive of the moulding compound reservoir [0116] 13 Filling funnel [0117] 14 Filter unit [0118] 15 Feed opening of the injection unit [0119] 16 First part of the connecting device [0120] 17 Second part of the connecting device [0121] 18 Bolt [0122] 19 Gasket [0123] 20 Spherical section [0124] 21 Guide element [0125] 22 Retaining element [0126] 23 Washer [0127] 24 Connecting disc [0128] 25 Flange [0129] 26 Clamping element [0130] 27 Opening