Device for producing metal sheets or hollow chamber plates from extruded profiles

Abstract

An apparatus for producing metal sheets from extruded profiles of small thickness or of hollow chamber plates of light metal, preferably of magnesium or magnesium alloys, comprises an extruder for producing an extruded profile which is open along a surface line. A separating device is provided for cutting the extruded profile to length corresponding to the length of the metal sheet to be produced, or the hollow chamber plate to be produced. A bending unit is used for deforming the extruded profile into a U-shaped profile. An expansion unit is provided for expanding the U-shaped profile into a flat metal sheet or a hollow chamber plate. A stacking unit is also provided. At least one expansion unit is arranged parallel to the extrusion line and thus the extrusion and expanding processes are decoupled from one another.

Claims

1. An apparatus for producing flat metal sheets (19) or hollow chamber plates (20), comprising: an extruder (1) for producing an extruded profile (7) with a longitudinal opening; a separating device (6) for cutting the extruded profile (7) to length corresponding to a length of the flat metal sheets (19) or the hollow chamber plates (20) to be produced; a bending unit (4) for widening the longitudinal opening and creating a-U-shaped configurations of the extruded profile (7); a first expansion unit (3) for expanding a first of the U-shaped configurations into the flat metal sheets (19) or the hollow chamber plates (20); a first stacking unit (5) arranged downstream of the first expansion unit (3); a second expansion unit (3) for expanding a second of the U-shaped configurations of the extruded profile (7) into the flat metal sheets (19) or the hollow chamber plates (20); a second stacking unit (5) arranged downstream of the second expansion unit (3); and a robot for transferring the first of the U-shaped configurations from the bending unit (4) to the first expansion unit (3) and for transferring the second of the U-shaped configurations from the bending unit (4) to the second expansion unit (3), wherein the extruded profile (7) emerges from the extruder (1) in a direction of extrusion, wherein the first expansion unit (3) and the second expansion unit (3) are arranged parallel to the direction of extrusion on opposite sides of the bending unit (4) such that an axis perpendicular to the direction of extrusion extends through at least a portion of the bending unit (4), the first expansion unit (3) and the second expansion unit (3).

2. The apparatus according to claim 1, wherein the extruded profile is made of magnesium or a magnesium alloy.

3. The apparatus according to claim 1, further comprising a sizing and squeezing device arranged between the first expansion unit (3) and the first stacking unit (5).

4. The apparatus according to claim 3, wherein the sizing and squeezing device is a hydraulic press and comprises two heated embossing plates (24) that can be moved relative to one another.

5. The apparatus according to claim 1, wherein the first expansion unit (3) comprises two clamping devices (16) that can be moved apart and rotated, wherein each of the clamping devices (16) comprises a U-shaped rail and a clamping rail (18) arranged therein, the clamping rail (18) being acted upon by at least two hydraulic cylinders (17).

6. The apparatus according to claim 1, wherein the first expansion unit (3) is formed by a 3-roller unit (25), wherein the 3-roller unit (25) consists of two upper rollers (26) arranged parallel to each other and a lower roller (27) that can be moved towards the upper rollers (26), and wherein a feed or transport unit is allocated to the 3-roller unit.

7. The apparatus according to claim 1, wherein all parts of the apparatus that come into contact with the hollow chamber plates, the extruded profile (7) or the metal sheets (19) are provided with a coating or consist of a magnesium-compatible material in order to prevent direct contact with a ferrous material.

8. The apparatus according to claim 1, wherein the separating device (5) is a non-machining separating device when producing metal sheets (19).

9. The apparatus according to claim 8, wherein the separating device (5) is a wedge or pinch cutting device.

10. The apparatus according to claim 1, wherein the separating device (5) is a machining separating device when producing flat hollow chamber profiles (20).

11. The apparatus according to claim 10, wherein the separating device (5) is a saw.

12. The apparatus according to claim 1, wherein the robot comprises a mechanical or pneumatic gripping system.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention shall be described in more detail by reference to an exemplary embodiment and the drawings.

(2) FIG. 1 is a block diagram illustrating the principle structure of the apparatus.

(3) FIG. 2 shows a cutout of the apparatus.

(4) FIG. 3a and FIG. 3b illustrate cutting of the hollow profile to length.

(5) FIG. 4 shows a cross-section A-A of FIG. 2.

(6) FIG. 5, FIG. 5a, FIG. 5b, and FIG. 5c illustrate the expansion process of the U-shaped profile.

(7) FIG. 6 shows a U-shaped multi-chamber profile.

(8) FIG. 7 shows the sizing and squeezing unit.

(9) FIG. 8 shows an embodiment of an expansion unit.

(10) FIG. 9 illustrates a sequence of the production process.

DETAILED DESCRIPTION

(11) FIG. 1 shows the principal structure of the apparatus for producing metal sheets from extruded profiles. The apparatus essentially consists of an extruder 1 for producing an extruded profile 7 with an upstream furnace 2 for heating the extrusion billet 8 to extrusion temperature. A bending unit 4 is arranged downstream of the extruder 1 in the extrusion direction. A separating device 6 is used for cutting to length the extruded profile 7—hereinafter referred to as hollow profile 7. Two expansion units 3 are arranged parallel to the extrusion direction with a subsequent stacking unit 5.

(12) All devices of the apparatus are interlinked. The transfer of the U-shaped profile 7 to the expansion unit 3 and of the expanded profile 7 to the stacking unit 5 and, if necessary, to the interposed sizing and squeezing unit is carried out by handling devices, preferably by industrial robots. For this purpose, the handling devices are equipped with mechanical or pneumatic gripping systems.

(13) FIG. 2 shows a cutout of the apparatus for producing metal sheets from extruded profiles 7. The extrusion billet 8 heated in the furnace 2 to extrusion temperature between 200 and 520° C., preferably to 470° C., is inserted into the recipient 10 of the extruder 1 and pressed out to an open profile 7. That is, the profile 7 is slit in the longitudinal direction, by applying pressure through the die 9. FIG. 4 shows a section A-A through the pressed out profile 7.

(14) After a predetermined length of the profile 7 has been pressed out, the extruder is stopped and the profile 7 is cut to length by the separating device 6 according to the length of the metal sheet to be produced. FIG. 3a shows a variant of the separating device 6 for cutting the open profile 7 to length. The hollow profile 7 is cut to length from the extruded strand by a wedge cutting device 14, with which one or more wedge cutting wheels 14 cut the profile 7 from the extrusion around the circumference. The wedge cutting wheels(s) separate the material lying on a base and is pressed apart by moving the wedge-shaped cutting edges towards each other. The base is formed by extending the piercing plug 12.

(15) An additional variant of cutting to length the hollow profile 7 from the extrusion is shown in FIG. 3b. A ring-shaped counter bearing 13 is located on the outer side of the profile 7. The wedge cutting device 14 is driven into the interior. Two opposite, hydraulically movable wedge cutting wheels are arranged at the end and separate the material with simultaneous rotary movement. The application of pressure to and rotation of the wedge cutting device 14 is effected by the drive and hydraulic device 15.

(16) Wedge or pinch cutting has the advantage that, being a chipless cutting process, it does not produce any chips or splinters that would otherwise have to be removed from the surface in the cutting area.

(17) After the profile 7 has been cut to length, it is released from the extrusion unit. The profile 7, which is slotted in the longitudinal direction and placed on the angle rails 11 of the bending unit 4, is moved out of the area of the separating device 6. Subsequently, the profile 7 is bent open into a U-shape (FIG. 5) by moving the angle rails 11 apart.

(18) The U-shaped bent profile 7 is grasped by a handling device (not shown in detail) and transferred to the expansion unit 3. Here, the U-shaped profile 7 is fully expanded. For this purpose, the profile 7 is inserted with its longitudinal sides into the rotatably mounted clamping units 16, wherein the profile 7 is deformed into a flat sheet by moving the clamping units 16 apart. FIGS. 5 a to 5 c show the individual sections of the expanding of the profile 7 to form a flat metal sheet 19.

(19) The U-shaped bent profile 7 inserted in the clamping units 14 of the expansion unit 3 is clamped by the clamping rail 18 in the clamping unit 16. Clamping is achieved by applying pressure to the clamping rail 18. For this purpose, at least two hydraulic cylinders 17 are arranged along the outer side of the clamping rails over their length.

(20) The U-shaped profile 7 is expanded to form a flat metal sheet 19 (FIG. 5 c) by driving apart the clamping units 16. Subsequently, the metal sheet 19 is gripped by a handling device, preferably by a suction pad, and placed in the stacking unit 5.

(21) If the metal sheets 19 still show unevenness after the expanding process, they are transferred to a sizing and squeezing unit prior to being placed in the stacking unit 5. For this purpose, the metal sheet 19 is clamped on the transverse side and moved into the sizing and squeezing station by a linear drive. In the sizing and squeezing unit, the metal sheet 19 is hot squeezed, which removes any unevenness that may exist.

(22) The sizing and squeezing unit is formed by two heated embossing plates 24 that can be moved towards each other. The embossing plates 24 can be opened and closed by a simple hydraulic press.

(23) After the sizing and squeezing process, the metal sheet is picked up by a handling device with a suction pad and placed in the stacking unit 5.

(24) In a further exemplary embodiment, the production of hollow chamber plates 20 is described. FIG. 6 shows the extruded profile 7 produced by means of the extruder 1, which forms the basis for a hollow chamber plate 20.

(25) The extruded profile 7 is designed in such a manner that it assumes the shape of a flat hollow chamber plate 20 after expansion. The extruded profile 7 is designed in such a manner that the sections of the lower side 22 and the upper side 21 between the inner webs 23 have the same length. Consequently, the sections of the lower side 22 between the inner webs 23 are formed in an inwardly convex curved manner during extrusion. After the expansion process, the sections between the inner webs 23 on the lower side 22 and the upper side 21 have the same length.

(26) The extruded profile 7 emerging from the die of the extruder 1 in a first step is cut off according to the hollow chamber plate 20 to be produced. As the separating device 6, a machining cutting device, for example a saw, is preferably used here. This is connected to an extraction system for the chips.

(27) Subsequently, the extruded profile 7 is bent up into a U-shaped profile 7 by means of the bending unit 4 and is taken further into an expansion unit 3. The bending up to a U-shaped profile 7 takes place by moving the angle rails 11 of the bending unit 4 apart.

(28) In the expansion unit 3, the U-shaped profile 7 is expanded to form a flat hollow chamber plate 20. After the expansion process, the hollow chamber plate 20 is placed in a sizing and squeezing unit.

(29) The sizing and squeezing unit is shown schematically in FIG. 7. It essentially consists of two heated embossing plates 24 that can be moved towards each other and between which the hollow chamber plate 20 is arranged during the sizing and squeezing process. In this manner, the hollow chamber plates 20 are brought to a uniform dimension with regard to the distance between the upper and lower sides 21, 22 and at the same time are also straightened.

(30) FIG. 8 shows an additional embodiment of the expansion unit. This essentially consists of a 3-roller unit 25, the two upper rollers 26 and a lower roller 27 that can be moved in the direction of the upper rollers 26. A pair of rollers 28 is arranged in front of the 3-roller unit 25, with the assistance of which the profile 7 is transported into and through the 3-roller unit 25.

(31) After the longitudinal side (front edge) of the profile 7 has been gripped by the pair of rollers 28, it is pushed in the direction of the 3-roller unit. If the front edge of the profile 7 reaches the second upper roller 26, the lower roller 27 is moved in the direction of the upper rollers 26. When the profile 7 is pushed further through the 3-roller unit 25, it is formed into a flat metal sheet 19, that is, it is expanded from the U-shaped profile 7 into the metal sheet 19. This can be followed by a sizing and squeezing step, or the metal sheet 19 can be placed directly in the stacking unit 5.

(32) FIG. 9 shows a simplified representation of the production process. Starting from the extrusion billet 8, a tubular open extrusion profile 7 is produced by means of an extruder 1 and is separated from the extrusion by a separating device 6 corresponding to the length of the plate 19 or the hollow chamber plate 20. The extruded profile 7 is subsequently bent into a U-shape. After the transfer to an expansion unit 3, the extruded profile 7 is expanded to form a metal plate 19 or a hollow chamber plate 20.

(33) All parts of the apparatus that come into contact with the U-shaped profile 7 or the metal sheet 19 or the hollow chamber plate 20 are provided with a coating, preferably with a ceramic material, or are made of a magnesium-compatible material, in order to prevent direct contact with a ferrous material.

(34) The apparatus for producing metal sheets or hollow chamber plates from extruded profiles has the advantage that the expansion process to form a flat sheet or hollow chamber plate is decoupled from the extrusion process, by which the number of cycles for the production can be substantially increased.

(35) The extrusion of magnesium sheet also has the advantage of being able to produce very thin sheet thicknesses in a single process step and thus represents an alternative to rolling or casting-rolling.

(36) Not only can very thin sheet thicknesses be realized here, but also very wide sheets can be produced by extruding hollow profiles, for example tubes. The extrusion process can also be used to produce very wide hollow chamber plates. The width results from the circumference of the extruded profiles in accordance with the formula u=d*n. For example, for a tube diameter of 300 mm, a sheet with a width of approximately 942 mm can be produced.

LIST OF REFERENCE SIGNS

(37) 1 Extruder 2 Furnace 3 Expansion unit 4 Bending unit 5 Stacking unit 6 Separating device 7 Extruded profile/profile 8 Extrusion billet 9 Die 10 Recipient 11 Angled rail 12 Piercing plug 13 Counter bearing 14 Wedge cutting device 15 Drive and hydraulic unit 16 Clamping unit 17 Hydraulic cylinder 18 Clamping rail 19 Metal sheet 20 Hollow chamber plate 21 Upper side 22 Lower side 23 Inner web 24 Embossing plates 25 3-roller unit 26 Upper roller 27 Lower roller 28 Pair of rollers