PROTECTIVE COVER FOR A PLASTICISING CYLINDER

Abstract

A protective cover for a plasticising cylinder of a shaping machinehas an elongate internal space which is enclosed by at least one wall and in which the plasticising cylinder can be arranged. A terminal box for heating strips arranged on the plasticising cylinder projects into the internal space, and one of the walls of the protective cover has an opening which is closed by an openable cover member. In the opened condition, the opening allows access to the terminal box or the interior of the terminal box.

Claims

1. A protective cover for a plasticising cylinder of a shaping machine, having an elongate internal space which is enclosed by at least one wall and in which the plasticising cylinder can be arranged, wherein a terminal box for heating strips arranged on the plasticising cylinder projects into the internal space and one of the walls of the protective cover has an opening which is closed by an openable cover member and which in the opened condition allows access to the terminal box or the interior of the terminal box.

2. A protective cover according to claim 1, wherein the terminal box has a side which faces towards the plasticising cylinder in the mounted condition and which extends in the longitudinal direction of the internal space and is of a concave configuration.

3. A protective cover according to claim 2, wherein the ratio between the spacing of a lateral wall of the protective cover or a lateral portion of the at least one wall from the central axis of the plasticising cylinder and the external radius of the plasticising cylinder is in a range of (Y/R) approximately equal to 3 to about 1.1—preferably (Y/R) approximately equal to 2.5 to about 1.4—and is preferably less than or equal to 1.6.

4. A protective cover according to claim 1, wherein a control and/or power electronic means for the heating strips is arranged in the internal space of the protective cover, preferably in the terminal box.

5. A protective cover according to claim 1, wherein the openable cover member is in the form of a cover member of the terminal box.

6. A protective cover according to claim 5, wherein the cover member of the terminal box adjoins in flush relationship the wall having the opening so that the terminal box is arranged completely in the internal space except for the cover member.

7. A protective cover according to claim 1, wherein interface plugs of the terminal box are so arranged that the plugging directions extend parallel to that wall of the protective cover, that has the opening.

8. A protective cover according to claim 1, wherein the opening is arranged at a lateral wall or a lateral portion of the at least one wall of the protective cover.

9. A protective cover according to claim 1, wherein there is provided a cooling device for the terminal box.

10. A plasticising unit for a shaping machine having a protective cover according to claim 1 and a plasticising cylinder in the internal space of the protective cover.

11. A plasticising unit according to claim 10, wherein a cable run connecting the terminal box to the heating strips is arranged above the plasticising cylinder.

12. A plasticising unit according to claim 1, wherein a nozzle heating strip and an associated temperature sensor are connected to the terminal box by way of a plug connection.

13. A plasticising unit according to claim 1, wherein the terminal box has at least one information interface for the connection of a sensor or a data bus.

14. A plasticising unit according to claim 1, wherein the terminal box is thermally insulated or uncoupled from the heating strips and the plasticising cylinder.

15. A plasticising unit according to claim 1, wherein the plasticising unit has a plasticising cylinder support and a further support.

16. A plasticising unit according to claim 1, wherein the plasticising unit has a display means and/or interface for an operator.

17. A shaping machine, in particular an injection moulding machine, having a plasticising unit according to claim 1.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0047] An embodiment of the invention is described with reference to the Figures in which:

[0048] FIG. 1 shows an isometric view of a plasticising unit according to the invention,

[0049] FIG. 2 shows a view of the end of the plasticising unit,

[0050] FIG. 3 shows a further view of the end of the plasticising unit,

[0051] FIG. 4 shows a side view of the plasticising unit,

[0052] FIG. 5 shows a protective cover according to the invention with opened cover member, and

[0053] FIGS. 6a-6c show isometric views from below on to the protective cover.

DETAILED DESCRIPTION OF THE INVENTION

[0054] FIG. 1 shows a portion of a plasticising unit of a shaping machine according to the invention, which otherwise corresponds to the state of the art. It is possible to see a protective cover 1 having two lateral walls 3a, 3b and an upper wall 3c in a U-shaped configuration. The protective cover 1 is open downwardly. It is possible to see the plasticising cylinder 2 which is arranged in the internal space 4 in the protective cover 1 and on which heating strips 6 are arranged. The protective cover 1 has an opening 8 (see FIG. 5) which is closed in FIG. 1 by a cover member 7. In the illustrated embodiment the cover member 7 is in the form of a cover member of the terminal box 5 and adjoins the wall 3a of the protective cover 1 in flush relationship. After removal of the screws (here six) which can be seen the content of the terminal box 5 is accessible from the exterior without further parts of the protective cover 1 having to be dismantled. The cover member 7 can naturally be openable in any fashion. In operation the plasticising cylinder 2 is supported on the underlying surface by way of a plasticising cylinder support 10. After the plasticising unit has been dismantled it can be supported preferably at least in a three-point support configuration by way of the plasticising cylinder support 10 and a further support 11 (which has for example at least two support points).

[0055] FIG. 2 shows that in this embodiment the terminal box 5 has a side which is towards the plasticising cylinder 2 and which extends in the longitudinal direction of the internal space 4 and is concave. The ratio between the spacing Y of a lateral wall 3a, 3b of the protective cover 1 from the central axis of the plasticising cylinder 2 and the external radius R of the plasticising cylinder 2 is in a range of Y/R approximately equal to 3 to about 1.1—preferably (Y/R) approximately equal to 2.5 to about 1.4—and is preferably less than or equal to 1.6 (see FIG. 3).

[0056] FIG. 4 shows a wide view of the plasticising unit shown in the preceding Figures, with a spacing A being illustrated. This involves the spacing A between a filling opening of the plasticising cylinder 2 and that plug which is closest to the filling opening of the plasticising cylinder 2. Ideally, with the same outside diameter of the plasticising cylinder 2 and a given structural size of the plasticising unit, it involves a defined spacing A. The magnitude of the spacing A however can be freely selected.

[0057] FIGS. 6a to 6c show views into the empty protective cover 1, that is to say without the plasticising cylinder 2 arranged in the internal space, but with the terminal box 5 being shown.

LIST OF REFERENCES

[0058] 1 protective cover [0059] 2 plasticising cylinder [0060] 3a, 3b, 3c walls of the protective cover [0061] 4 internal space in the protective cover [0062] 5 terminal box [0063] 6 heating strip [0064] 7 cover member of the protective cover [0065] 8 opening in the protective cover [0066] 9 side of the terminal box that is towards the plasticising cylinder [0067] 10 plasticising cylinder support [0068] 11 further support