Bridge Tool for Producing Extruded Profiled Elements of Varying Cross-Section

Abstract

The invention relates to a bridge tool for a device for directly extruding hollow profiled elements of variable wall thickness, comprising a die (6) and at least one mandrel element (5) having a first end facing the die opening and an opposite second end, the outer profile contour of a hollow profiled element being defined by the geometry of the die opening and the inner cross-section of a hollow profiled element being defined by the at least one mandrel element (5), characterized in that the at least one mandrel element (5) has at least one cut-out, in which an inner sliding mandrel is arranged, said inner sliding mandrel being mounted for movement in the axial direction, the inner sliding mandrel having different cross-sections in the first end region of the inner sliding mandrel facing the first end of the mandrel element.

Claims

1. A bridge-die tool for an apparatus for the direct extrusion of hollow profiles of variable wall thickness, comprising a bridge die and at least one mandrel element having a first end, which is directed toward the bridge-die opening, and a second end, which is located opposite the first end, wherein the outer contour of a hollow profile is defined by the geometry of the bridge-die opening and the inner cross section of a hollow profile is defined by at least one mandrel element, characterized in that the at least one mandrel element has at least one cutout, in which an inner displacement mandrel is mounted in an axially movable manner, wherein the inner displacement mandrel has different cross sections in its first end region, which is directed toward the first end of the mandrel element.

2. The bridge-die tool as claimed in claim 1, characterized in that the mandrel element comprises at least one second axial cutout, which extends axially along the second end region of the inner displacement mandrel, said second end region being located opposite the first end region of the inner displacement mandrel, wherein a transverse slide which is arranged, in particular more or less, perpendicularly to the at least one mandrel element is included and is introduced, at least in part, into the at least one second cutout, and wherein the transverse slide is in operative connection with the inner displacement mandrel, in particular is fixed to the inner displacement mandrel.

3. The bridge-die tool as claimed in claim 2, characterized in that the transverse slide can be brought into, or is in, operative connection with at least one drive device directly or by means of at least one crossmember, wherein the drive device is designed, and intended, to move the transverse slide and the inner displacement mandrel in the axial direction.

4. The bridge-die tool as claimed in claim 3, characterized in that a first crossmember is arranged at a first radial end of the transverse slide and a second crossmember is arranged at a second radial end of the transverse slide, said second radial end being located opposite the first radial end, wherein the first crossmember can be brought into, or is in, operative connection with a first drive device and/or the second crossmember can be brought into, or is in, operative connection with a second drive device.

5. The bridge-die tool as claimed in one of claims 2 to 4, characterized in that the first and/or the second drive device are/is designed in the form of a linear drive, in particular in the form of a hydraulic cylinder.

6. The bridge-die tool as claimed in one of the preceding claims, characterized in that the inner displacement mandrel has a trapezoidal or triangular cross section, in part, in the region of its first end, as seen in the axial direction.

7. The bridge-die tool as claimed in claim 6, characterized in that the inner displacement mandrel is in operative connection with at least one wedge-shaped element on or in the region of its first end, or said wedge-shaped element is brought into abutment, in part, with the inner displacement mandrel, wherein in particular the further angle of gradient of that side of the at least one wedge-shaped element which is directed toward the inner displacement mandrel is smaller than, or equal to, the angle of gradient , and therefore an axial displacement of the inner displacement mandrel is converted into a corresponding radial displacement of the at least one wedge-shaped element.

8. The bridge-die tool as claimed in claim 7, characterized in that at least one second wedge-shaped element is arranged in mirror-symmetrical fashion in relation to the first wedge-shaped element on that side of the inner displacement mandrel which is located opposite the first wedge-shaped element.

9. The bridge-die tool as claimed in claim 7 or claim 8, characterized in that the at least one wedge-shaped element is connected to the mandrel element by means of a first dovetail guide, wherein the at least one dovetail guide provides for movement of the at least one wedge-shaped element exclusively in the radial direction, and wherein the dovetail guide is formed in particular by the mandrel element and the at least one wedge-shaped element.

10. The bridge-die tool as claimed in one of claims 7 to 9, characterized in that the inner displacement mandrel and the at least one wedge-shaped element are connected by means of an axially formed second dovetail guide, and therefore an axial movement of the inner displacement mandrel is converted into a radial movement of the at least one wedge-shaped element.

11. The bridge-die tool as claimed in one of the preceding claims, characterized in that the first cutout of the mandrel element and the at least one inner displacement mandrel form a third dovetail guide in the axial direction, and therefore the inner displacement mandrel and the mandrel element are connected to one another by means of a dovetail guide.

12. A direct-extrusion apparatus comprising a bridge-die tool as claimed in one of the preceding claims.

13. The use of a bridge-die tool as claimed in one of claims 1 to 11 so that one or more extruded profiles of cross sections which vary in the extruding direction are produced in a direct-extrusion apparatus.

Description

[0052] In the drawings:

[0053] FIG. 1: shows a perspective view of one embodiment of a bridge-die tool according to the invention;

[0054] FIG. 2: shows a schematic view of the bridge-die tool according FIG. 1;

[0055] FIG. 3: shows a schematic side view, in section, of the bridge-die tool according to FIG. 1; and

[0056] FIG. 4: shows a perspective view of one embodiment of a mandrel element of a bridge-die tool according to the invention.

[0057] FIG. 1 illustrates a perspective view of one embodiment of a bridge-die tool according to the invention. The latter comprises a container 1, on the outer sides of which are arranged two linear drives 2 in the form of hydraulic cylinders. Each of the linear drives 2 here is connected to a crossmember 3, the crossmembers terminating on two opposite sides of a transverse slide 4 and being connected to the latter in a form-fitting manner. The gap between a mandrel element 5 and the bridge die 6 here defines the wall thickness of the hollow profiles which are to be produced. The bridge die 6 here is fastened on a pressure-exerting plate 7. The mandrel element 5 here additionally comprises wedge-shaped elements 8 and also an inner displacement mandrel 9.

[0058] FIG. 2 illustrates a plan view, in section, of the bridge-die tool according to FIG. 1. In common with the side view, in section, in FIG. 3, the functional principle of a bridge-die tool according to the invention is clearly evident. The inner displacement mandrel 9 here is arranged in a first cutout 10, which extends in the axial direction and is adjoined by two second cutouts 11 for the transverse slide 4. Movement of the linear drives 2 results in displacement of the crossmembers 3 and of the transverse slide 4, and therefore of the inner displacement mandrel 9, in the radial direction. This axial displacement of the inner displacement mandrel 9 here results in a radial movement of the wedge-shaped elements 9, and therefore in alteration of the gap between the mandrel element 5 and the bridge die 6. This alteration in the gap results in the cross section of the hollow profile which is to be produced altering.

[0059] FIG. 4 shows, in addition, two first dovetail guide 13 for the wedge-shaped elements 8 and also two second dovetail guides 14. Said first dovetail guides 13 ensure that the wedge-shaped elements 8 can move exclusively in the radial direction, whereas the second dovetail guides 14 mean that, alongside radially outwardly acting compressive forces, during displacement of the inner displacement mandrel 9, also tensile forces can be transmitted from the inner displacement mandrel 9 also the wedge-shaped elements 8.

[0060] The features of the invention which are disclosed in the foregoing description, the claims and the drawings can be essential both individually, and in any desired combination, for implementing the invention in its various embodiments.