METHOD AND DEVICE FOR PRODUCING AN EXTRUDED PRODUCT

Abstract

The invention relates to a method and a device for producing an extruded product. In the method an extrusion device is provided comprising: a container (7); a first container bore (5), formed in the container (7) and in which a first extrusion punch (10) is arranged; a second container bore (6), formed in the container (7) separately from the first container bore (5) and in which a second extrusion punch (11) is arranged; and a moulding tool (15) with a moulding cavity (14), which are connected to the first and the second container bore (5, 6). The method further comprises the following: arranging a first material billet (8) made of a first material (2) in the first container bore (5); arranging a second material billet (9) made of a second material (3) which differs from the first material (2) in the second container bore (6); and extruding an extruded product (1) in which the first and the second material (2, 3) are connected in a form-fitting and integrally bonded manner, comprising the following: feeding the first extrusion punch (10) in the first container bore (5) in such a manner that the first material (2) is thereby pressed into the moulding cavity (14) of the moulding tool (15) and thereby formed; feeding the second extrusion punch (11) in the second container bore (6) in such a manner that the second material (3) is thereby pressed into the moulding cavity (14) of the moulding tool (15) and thereby formed; and joining the first and second material (2, 3) in a form-fitting and integrally bonded manner to form an extruded product (1) in the moulding tool (15). A first feeding during feeding of the first extrusion punch (10) in the first container bore (5) and a second feeding during feeding of the second extrusion punch (11) in the second container bore (6) are controlled independently of one another.

Claims

1. Method for producing an extruded product, comprising providing an extrusion device comprising a container; a first container bore, formed in the container and in which a first extrusion punch is arranged, a second container bore, formed in the container separately from the first container bore and in which a second extrusion punch is arranged; and a moulding tool with a moulding cavity, which are connected to the first and the second container bore; arranging a first material billet made of a first material in the first container bore; arranging a second material billet made of a second material which differs from the first material in the second container bore; and extruding an extruded product in which the first and the second material are connected in a form-fitting and integrally bonded manner, comprising the following: feeding the first extrusion punch in the first container bore in such a manner that the first material is thereby pressed into the moulding cavity of the moulding tool and thereby formed; feeding the second extrusion punch in the second container bore in such a manner that the second material is thereby pressed into the moulding cavity of the moulding tool and thereby formed; and joining the first and second material in a form-fitting and integrally bonded manner to form an extruded product in the moulding tool, wherein a first feeding during feeding of the first extrusion punch in the first container bore and a second feeding during feeding of the second extrusion punch in the second container bore are controlled independently of one another.

2. The method according to claim 1, characterized in that the connecting in a integrally bonded and form-fitting manner in the moulding tool is made between the first and second material.

3. Method according to claim 1, characterized in that the first and the second material are introduced into the moulding cavity at a different flow rate.

4. Method according to claim 1, characterized in that the feeding of the first extrusion punch in the first container bore is carried out at a first feed rate and the feeding of the second extrusion punch in the second container bore is carried out at a second feed rate which differs from the first feed rate.

5. Method according to claim 1, characterized in that during movement in the first container bore the first extrusion punch is driven by means of a first actuator and during movement in the second container bore the second extrusion punch is driven by means of a second actuator which is formed and controllable separately from the first actuator.

6. Method according to claim 1, characterized in that an extrusion profile is produced as an extruded product.

7. Method according to claim 1, characterized in that an extrusion device is provided in which the first container bore has a first cross-section and the second container bore has a second cross-section which differs from the first cross-section, transverse to the respective feed direction.

8. Method according to claim 1, characterized in that an extrusion device is provided in which the first container bore has the first cross-section and the second container bore has the second cross-section which is the same as the first cross-section, transverse to the respective feed direction.

9. Method according to claim 1, characterized in that an extrusion device is provided in which, transverse to the respective feed direction, the first container bore has a first circular transverse section, and the second container has a second circular cross section.

10. Method according to claim 1, characterized in that an extrusion device is provided in which the first container bore and the second container bore are sealed with respect to one another.

11. Device for producing an extruded product, comprising a container; a first container bore which is formed in the container and in which an extrusion punch is arranged; a second container bore which is formed in the container separately from the first container bore and in which a second extrusion punch is arranged; and a moulding tool with a moulding cavity which is connected to the first and the second container bore in such a manner that during extrusion by means of feeding the first extrusion punch in the first container bore and feeding the second extrusion punch in the second container bore, a first material of a first material billet from the first container bore and a second material of a second material billet which differs from the first material can be introduced into the moulding cavity from the second container bore to produce an extruded product in which the first and the second material are connected in a form-fitting and integrally bonded manner, wherein a first feed during feeding of the first extrusion punch in the first container bore and a second feed during feeding of the second extrusion punch in the second container bore can be controlled independently of one another.

Description

DESCRIPTION OF EXEMPLARY EMBODIMENTS

[0040] Further exemplary embodiments are explained hereinafter with reference to figures of a drawing. In the figures:

[0041] FIG. 1 shows a schematic diagram of a device for producing an extruded product;

[0042] FIG. 2 shows a perspective diagram of a container for an extrusion device in which the first and the second extrusion punch are arranged in the first and the second container bore;

[0043] FIG. 3 shows a schematic perspective diagram of an arrangement with two extrusion punches for pressing material billets with the same feed rates;

[0044] FIG. 4 shows a schematic perspective diagram of an arrangement with two extrusion punches for pressing material billets with different feed rates and

[0045] FIG. 5 shows a schematic diagram of a moulding tool from the front.

[0046] FIG. 1 shows a schematic diagram of a device for producing an extruded product 1 in which a first material 2 and a second material 3 are joined together in a form-fitting and integrally bonded manner by means of extrusion along a joining connection or seam 4. The extruded product 1 can comprise an extrusion profile.

[0047] The formulation extrusion profile in the meaning used here comprises all profile geometries that can be produced with the aid of the extrusion process. These include, for example, both solid profiles and also hollow profiles as well as semi-hollow profiles in arbitrary geometries. Thus, for example extruded sheets as well as tubes, window profiles or round rods are known as extrusion profiles.

[0048] In order to produce the extruded product 1, a first material billet 8 made of a first material 2 and a second material billet 9 made of a second material 3 are arranged in a first and a second container bore 5, 6 of a container 7. The first and the second container bore 5, 6 provide a respective cavity with a cylindrical shape which can have a round, angular or oval cross-section. A first and a second extrusion punch 10, 11 are arranged in the container bores 5, 6, which are each displaceable in the axial direction in the associated container bore 5, 6.

[0049] The first and the second extrusion punch 10, 11 are each assigned a first and a second actuator 12, 13 which are adapted to apply force to the respective extrusion punch 10, 11 so that the extrusion punches 10, 11 execute a feed movement in the direction of a moulding cavity 14 of a moulding tool 15 in order to thus introduce the first and the second material 2, 3 into the moulding cavity 14. For this purpose, the first and the second container bore 5, 6 are connected to the moulding cavity 14 in such a manner that the material of the first and the second material billet 8, 9 is introduced in the moulding cavity 14 and is thereby moulded. The application of pressure has the result that the joining connection 4 between the first and the second material 2, 3 is formed in the moulding cavity 14.

[0050] With the aid of the first and the second actuator 12, 13 the first and the second extrusion punches 10, 11 can execute decoupled feed movements during extrusion. In particular, the extrusion punches 10, 11 can move at different speeds during feeding. By means of the independent setting of the two feed movements it is possible to set different flow rates for the transition of the first and the second material 2, 3 into the moulding cavity. The first and the second material 2, 3 can, for example, be different metallic materials but the use of the same metallic materials for the two material billets 8, 9 can also be provided. The extruded product 1 produced can be an extrusion profile.

[0051] Further exemplary embodiments are explained hereinafter with reference to FIGS. 2 to 5. The same reference numbers as in FIG. 1 are used for the same features.

[0052] FIG. 2 shows a schematic diagram of an arrangement for an extrusion device in which extrusion punches 10, 11 having different cross-sections are arranged in the first and the second container bore 5, 6. Whereas the first extrusion punch 10 has a round cross-section, the second extrusion punch 11 is provided with an angular (flat) cross-section. Accordingly, the first and the second container bore 5, 6 have a round and an angular cross-section. In the various embodiments the extrusion punches 10, 11 are arranged in a form-fitting manner in the associated container bore 5, 6. According to FIG. 2, the material billets 8, 9 then have a round and an angular cross-section.

[0053] A form-fitting seal can be achieved by means of a so-called press disk (not shown) positioned between extrusion punches 10, 11 and material billets 8, 9. This is used both fixedly in the sense of constructively temporarily connected to one another but exchangeablyand loosely.

[0054] FIG. 3 shows a schematic diagram of elements of an arrangement for an extrusion device in which the first and the second material billets 8, 9 are formed with the same billet length. The first and the second container bore 5, 6 also have the same cross-section. During extrusion it can then be provided to operate the first and the second extrusion punches 10, 11 at the same feed rate.

[0055] In contrast, FIG. 4 shows a schematic diagram of elements for an arrangement of an extrusion device in which the first and the second material billets 8, 9 are formed with different length. During extrusion the first extrusion punch 10 can then be operated at a different feed rate from the second extrusion punch 11.

[0056] In order to position the container 7 and the moulding tool 15 with the moulding cavity 14 relative to one another during the actual extrusion process, it can be provided to form constructive elements (not shown) assigned to one another on the container 7 and on the moulding tool 15. When joining together container 1 and moulding tool 15 in such a manner that the moulding cavity 14 of the first and the second container bore 5, 6 are arranged opposite one another, container 1 and moulding tool 15 are positioned relative to one another whereby a pin or a billet (not shown) engage in provided recesses or functional surfaces are aligned relative to one another.

[0057] FIG. 5 shows a schematic diagram of an embodiment of the moulding tool 15 from the front. The extruded product leaves the moulding cavity 14 through an (outlet) of the press channel 16 during operation during extrusion.

[0058] Aspects for further exemplary embodiments are explained hereinafter.

[0059] The method for hybrid extrusion by means of the multi-punch system uses, for example, the previously explained double-punch design with the multi-hole recipient or container 7 having the at least two cavities for the container bores 5, 6 and the corresponding number of individually movable and controllable extrusion punches 10, 11. The moulding tool 15 (extrusion die) is fed by the separate material flows. The moulding cavity 14 provides a welding chamber in order to join the partial strands of the materials by the action of pressure and temperature.

[0060] The extrusion punches 10, 11 move the press material into the material billets 8, 9 depending on the individual pressing conditions either at the same speed or at different speeds in the direction of the moulding tool 15. The individual container bores 5, 6 and corresponding press disks need not have the same diameter.

[0061] In the method the material billets 8, 9 are moved comparably with the direct extrusion through the container bores 5, 6 in the direction of the moulding tool 15 (die). Here, as a result of the relative movement between the inner walls of the container bores 5, 6 and the lateral surfaces of the material billets 8, 9, large parts of the oxides and impurities of the extrusion billets are already retained. The material flows feeding the moulding cavity 14 are already sheared and only contain a small proportion of impurities. Material flows having almost clean metallic surfaces flow into the moulding cavity. These are joined in the moulding cavity 14 and emerge as a composite strand (extrusion product) through the press channel 16 from the moulding tool 15.

[0062] Depending on the individual pressing conditions provided for the individual material flows, the punch speeds can be adapted so that, according to the product specification, defined volume fractions of the individual composite partners can be achieved in the product. At the same time, a defined positioning of the boundary layer can be influenced by specifying the volume fractions.

[0063] For the case where both extrusion punches 10, 11 press at the same speed and the container bores 5, 6 have the same cross-sectional areas, a profile is pressed in which the composite materials are pressed out adjacent to one another with the same volume flow. Due to a specifically adjustable individual process temperature for the two material billets 5, 6, composite flat profiles can be produced from the respective container bores 5, 6 both from material pairs having small and also large differences in the forming resistance.

[0064] For the case where both materials 2, 3 should be present in variously large volume fractions in the extruded product 1, different volume flows are obtained for each material (hybrid partner) when maintaining the container geometry. This is taken into account by adapting the billet length combined with two extrusion punches travelling at different speeds. For this purpose it is necessary that both extrusion punches can be moved in a path-controlled manner. In order to be able to control the extrusion punches independently, the extruder can have a separate hydraulic system for movement of the extrusion punches 10, 11.

[0065] In the embodiments described individual ones or several of the following advantages can be achieved compared with known extrusion methods: thermal and tribological decoupling of the material partners; adjustability of various billet insertion temperatures; separate control of flow rates of the material partners; individual adaptation of the necessary process variables; and specific steering of the material flows for variable volume ratios (load/function-adapted cross-sections).

[0066] The method makes it possible to produce metallic material composites within a single solid forming step. By using separately controllable extrusion punches and by means of the possibility of achieving different container bores (punch receptacles), the flow of the material partners with significantly different flow stresses can be adjusted in such a manner that a defined material arrangement (volume ratio of the material partners or wall thickness of the material partners, formation of the boundary layer) can be set over the complete profile length of the extruded product 1.

[0067] The features disclosed in the preceding description, the claims and the drawing can be important both individually and also in any combination for implementing the various embodiments.