EP4387783B1 - Procédé de fabrication de pièces en tôle et dispositif pour la mise en oeuvre de ce procédé - Google Patents

Procédé de fabrication de pièces en tôle et dispositif pour la mise en oeuvre de ce procédé

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Publication number
EP4387783B1
EP4387783B1 EP22765467.0A EP22765467A EP4387783B1 EP 4387783 B1 EP4387783 B1 EP 4387783B1 EP 22765467 A EP22765467 A EP 22765467A EP 4387783 B1 EP4387783 B1 EP 4387783B1
Authority
EP
European Patent Office
Prior art keywords
sheet metal
calibration
tool
preform
produced
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
EP22765467.0A
Other languages
German (de)
English (en)
Other versions
EP4387783A1 (fr
Inventor
Martin Kibben
Lars Bode
Michael Linnepe
Peter Sieczkarek
Daniel Nierhoff
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
ThyssenKrupp Steel Europe AG
Original Assignee
ThyssenKrupp Steel Europe AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by ThyssenKrupp Steel Europe AG filed Critical ThyssenKrupp Steel Europe AG
Publication of EP4387783A1 publication Critical patent/EP4387783A1/fr
Application granted granted Critical
Publication of EP4387783B1 publication Critical patent/EP4387783B1/fr
Active legal-status Critical Current
Anticipated expiration legal-status Critical

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Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/20—Deep-drawing
    • B21D22/30—Deep-drawing to finish articles formed by deep-drawing
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/02—Stamping using rigid devices or tools
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D22/00—Shaping without cutting, by stamping, spinning, or deep-drawing
    • B21D22/20—Deep-drawing
    • B21D22/206—Deep-drawing articles from a strip in several steps, the articles being coherent with the strip during the operation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D37/00—Tools as parts of machines covered by this subclass
    • B21D37/08—Dies with different parts for several steps in a process

Definitions

  • the invention relates to a method for manufacturing sheet metal components.
  • Methods and devices for manufacturing dimensionally accurate sheet metal components are disclosed in the prior art, see for example DE 10 2007 059 251 A1 , DE 10 2008 037 612 A1 , DE 10 2009 059 197 A1 , DE 10 2013 103 612 A1 , DE 10 2013 103 751 A1 , whereby the manufacturing process is carried out in at least two stages (forming processes).
  • a particularly flat blank is formed into a preform.
  • the preform has a material excess that is distributed as uniformly as possible. This additional material excess is compressed towards the plane of the sheet metal in the second stage, the so-called calibration.
  • the lengths of the local cross-sectional developments must therefore only change within narrow limits, even with varying influencing factors such as friction, the mechanical properties of the material batch used, and tool wear. It is therefore necessary to design the preforming tool with at least a spaced, outer blank holder, or preferably without any external blank holder at all (so-called "crash forming” or “embossing/folding”). This prevents the blanks in the preforming tool from stretching to varying degrees during the production of multiple components and when using different material batches, depending on the aforementioned influencing factors. Such uncontrolled stretching of the material from component to component would cause the distribution of excess material for subsequent calibration to potentially exceed the acceptable, process-reliable range.
  • preforms produced in this way sometimes spring back so significantly that they cannot be, or can only be partially, used for subsequent calibration.
  • excessive deviations from the target geometry can lead to unwanted dimensional deviations remaining in the final component even after calibration. This applies particularly to component deformations such as torsion, bending, and/or curvature, which may not be adequately captured during the calibration process, resulting in unwanted torsion and/or bending remaining even in final, calibrated components.
  • the existing concepts envisage creating a preform which essentially corresponds to the final geometry, whereby the preform tool with its working surfaces is essentially designed to match the working surfaces of the calibration tool.
  • the invention is therefore based on the objective of providing a generic method and a generic device with which a final component geometry can be produced that has as little or no deviation as possible from the final component geometry (target geometry).
  • the method for manufacturing a sheet metal component comprises at least two steps: forming a sheet metal preform having in cross-section a bottom, at least one frame, at least one transition between bottom and frame, optionally at least partially a flange and optionally at least partially a transition between frame and flange.
  • a preforming tool which acts on the sheet metal with its working surfaces, the resulting sheet metal preform having excess sheet material at least in certain areas; and final forming of the sheet metal preform into a sheet metal component in a calibration tool, which acts on the sheet metal preform with its working surfaces and in which the excess sheet material is essentially compressed in the plane of the sheet metal, thus increasing the sheet thickness at least in certain areas.
  • the working surfaces of the preforming tool for the sheet metal preform to be produced are arranged in comparison to the working surfaces of the calibration tool for the sheet metal component to be produced such that, when comparing the preforming tool and the calibration tool, considering the difference angle between the two principal axes of inertia oriented in the same direction with respect to the respective cross-sectional shape, through the centroids of two parallel cross-sectional surfaces at a distance of 100 mm from the tool gap enclosed by the respective working surfaces, a torsional angle difference of at least 0.2° is established.
  • a final component geometry can be produced that exhibits minimal to no deviation from the final component geometry (target geometry), particularly if a sheet metal preform is already produced that also exhibits minimal to no deviation from the final component geometry. It is generally known from the prior art that it is advantageous for the sheet metal preform geometry to be manufactured in such a way that it corresponds as closely as possible to the final component geometry set in the calibration tool. In particular, springback-induced curvature of the frame should be avoided in the preform itself, within the limitations of the process, which is characterized, for example, by reduced material flow control.
  • the inventive approach avoids deformation (torsion/twisting and/or bending) of the spring-back sheet metal preform relative to the final component geometry by appropriately designing the effective surfaces of the sheet metal preform, so that the better the spring-back sheet metal preform corresponds to the final sheet metal component, the more dimensionally accurate the result. the calibration will be completed, and the simpler the process control, especially in the calibration tool but also in any further subsequent processes, can be.
  • the difference in torsion angle is therefore the angle increment when comparing the preforming tool and the calibration tool when considering the difference angle between the principal axes of inertia oriented in the same way with respect to the respective cross-sectional shape through the centroids of two parallel cross-sectional surfaces at a distance of 100 mm of the tool gap enclosed by the respective working surfaces and amounts to at least 0.2°, in particular at least 0.5°, preferably at least 0.7°, more preferably at least 1°, more preferably at least 2° and more preferably at least 3°.
  • the working surfaces of the preforming tool are configured, in comparison to the working surfaces of the calibration tool, such that, in the sheet metal preform to be produced before springback, a curvature in the longitudinal extent of the sheet metal preform before springback is set, at least in certain areas, which deviates by at least 1%, in particular by at least 2%, preferably by at least 5%, more preferably by at least 7%, and most preferably by at least 9% from the variable curvature in the longitudinal extent of the sheet metal component to be produced.
  • the variable curvature of a component can be described as the curvature of an imaginary B-spline.
  • the centroid of the cross-sectional lines is determined at each point, and these intersection points are then connected using a B-spline, the curvature lines of the sheet metal component and the (compensated) sheet metal preform before springback, and thus the effective surfaces of the compensated preform tool, can be obtained.
  • the sheet metal preform before springback deviates by, for example, more than 5% from the curvature of the sheet metal component to be produced at the same location or in the same area, then the sheet metal preform is considered compensated with respect to the curvature of the sheet metal component in its longitudinal extent.
  • the sheet metal preform can be manufactured using any combination of forming processes in one or more steps.
  • Preforming can, for example, include a deep-drawing-like forming step.
  • multi-stage forming is also possible, including, for example, embossing the base to be created and raising the sides to be created or setting down the flanges to be created. Any combination of folding and/or bending and/or embossing is also conceivable.
  • the deep drawing performed for preforming for example, can be carried out in a single stage or in multiple stages.
  • forming without active material flow control can be used to manufacture the sheet metal preform.
  • Upsetting/calibration refers to the final forming of a sheet metal preform, which can be achieved, for example, through one or more pressing operations.
  • the resulting sheet metal preform incorporates excess sheet material in at least some areas.
  • This excess material has a developed length in the cross-section of the preform that is between 0.5% and 6% longer than the developed length of the finished sheet metal component (target geometry).
  • the developed length of these cross-sections in the preform is between 0.7% and 4.3% longer than that of the finished sheet metal component. If the developed length of the cross-sections varies too much during the manufacturing process of the preform, an insufficient amount of excess sheet material would be available for the subsequent calibration process, thus compromising the dimensional accuracy of the final component. The component would be affected.
  • the essentially finished sheet metal component can thus be understood as a final-formed sheet metal component.
  • the finished sheet metal component may undergo further processing steps that modify the component, such as the addition of connection holes and/or minor final trimming.
  • the aim is to design the calibration die in such a way that, apart from any necessary post-forming operations such as the removal of flanges or the subsequent introduction of embossing, no further forming steps are required.
  • Both the produced sheet metal preform and the finished sheet metal component essentially have a longitudinal and a transverse extent, with the longitudinal extent being larger than the transverse extent in most sheet metal components.
  • a cross-section means a section through the transverse extent of the sheet metal preform/sheet metal component.
  • a flange section is provided below the flange, at least on one side of the sheet metal component, extending longitudinally and/or transversely, particularly on both sides of the sheet metal component.
  • This section serves, for example, for connecting to other components and is also referred to as a joining flange.
  • the frame is provided at least on one side of the sheet metal component, extending longitudinally, particularly on both sides.
  • the sheet metal component has, for example, a substantially hat-shaped cross-section, with a frame on each side.
  • the frames may be identical or have different depths, particularly along their longitudinal extent.
  • An integral transition area is provided between the flange and the frames.
  • the base is integrally formed with the frame via a further transition area and, depending on the complexity of the sheet metal component to be produced, may not be limited to a single plane.
  • the component can be linear, but can also be designed to extend longitudinally and/or transversely, and can be positioned on different levels in certain areas.
  • the transitions between the individual levels in the base area can be stepped or curved; in particular, a so-called cranked design can be used.
  • the sheet metal component can also have shapes other than those extending longitudinally or along the longitudinal axis; for example, it can be arc-shaped, C-shaped, or L-shaped.
  • preform compensation offers the possibility of increasing the frame opening angle of the sheet metal preform relative to the final component geometry. This provides more clearance for necessary compensation measures without undercutting.
  • An increased frame opening angle of the sheet metal preform can be easily processed in the calibration tool, and in particular, reduced again if necessary to 0°, without significantly affecting the dimensional accuracy of the final component geometry.
  • very good results can be achieved in the subsequent calibration tool by adjusting the frame opening (even locally), especially for highly twisted sheet metal preforms.
  • the working surfaces of the preforming tool can advantageously be arranged in comparison to the working surfaces of the calibration tool so that a difference in the flange opening angle of at least 0.5°, in particular at least 1°, preferably at least 3°, preferably at least 5°, particularly preferably at least 8°, and more preferably at least 10° is set at the same location in the sheet metal preform to be produced compared to the sheet metal component to be produced.
  • the frame opening angle is the angle by which the component frame, relative to the direction of action of the press ram, can be rotated inwards at most around an axis oriented in the longitudinal direction of the sheet metal component in the transition area between the frame and the component base, before an undercut occurs in the tool.
  • the difference in the frame opening angle is the difference between the local frame opening angle of the sheet metal preform, in particular the compensated sheet metal preform or the compensated preforming tool, and the local frame opening angle of the sheet metal component at the same location or in the same cross-section.
  • the cross-sections or cross-sectional areas of the sheet metal preform and the sheet metal component under consideration lie in the same plane.
  • a steel sheet with a yield strength (Re ) of at least 400 MPa is used.
  • the yield strength can be, in particular, at least 500 MPa, preferably at least 600 MPa, and more preferably at least 700 MPa.
  • a device of the generic type comprising at least one preforming tool for preforming a sheet metal part into a sheet metal preform having in cross-section a bottom, at least one frame, at least one transition between bottom and frame, optionally at least partially a flange and optionally at least partially a transition between frame and flange, which acts on the sheet metal part with its effective surfaces, wherein the sheet metal preform has excess sheet metal material at least partially; and with at least one calibration tool for upsetting the sheet metal preform to a sheet metal component, which acts on the sheet metal preform with its working surfaces and in which the excess sheet metal material is upset in the sheet plane, wherein the working surfaces of the preform tool of the sheet metal preform to be produced are arranged in such a way as to, when comparing preform tool and calibration tool, when considering the difference angle between the two principal axes of inertia oriented in the same direction with respect to the respective cross-sectional shape through the centroids of two parallel cross-sectional surfaces at a distance
  • the working surfaces of the preforming tool have been adapted in such a way that the expected deviations of the sheet metal preform from the target geometry of the sheet metal component are pre-modeled in the opposite direction.
  • a spring-backed sheet metal preform will deform (twist/torsion) by X° around its main axis in longitudinal extension, so that the working surfaces of the preforming tool are corrected and adapted so that the sheet metal preform is pre-modeled in the opposite direction.
  • the direction is intentionally twisted by an approximately adequate amount.
  • the working surfaces of the preforming tool are arranged in such a way as to ensure that a difference in the frame opening angle of at least 0.5° is set at the same location in the sheet metal preform to be produced compared to the sheet metal component to be produced.
  • the device comprises a calibration tool with a calibration punch, a calibration die, and one or optionally several elements, wherein the element is arranged in the calibration die and is movable relative to the calibration die.
  • the contour of the calibration punch and the calibration die essentially corresponds to the base, the frame, and the optional flange, as well as the transition areas between the base and frame, and optionally between the frame and flange, of the nominal geometry of the sheet metal component.
  • the element arranged in the calibration die serves to position the sheet metal preform before upsetting/calibrating the preform on the calibration punch.
  • the calibration tool can comprise a calibration punch, a calibration die, and one or optionally several elements, wherein the element is arranged in the calibration punch and is movable relative to the calibration punch.
  • the calibration punch is located at the bottom and the calibration die at the top of the calibration tool and are movable relative to each other.
  • the component is positioned in the calibration die and moves, particularly via the ram stroke, i.e., together with the calibration die, towards the calibration punch. This movement presses the sheet metal preform downwards and positions it securely on the calibration punch, for example, by means of a spring, wedge driver, hydraulics, or pneumatics.
  • a relative movement occurs between the calibration die and the component until the component is finally flush within the calibration die at the bottom dead center.
  • the calibration punch is positioned at the top and the calibration die at the bottom of the calibration tool and are movable relative to each other.
  • the element is located in the calibration punch and moves, particularly via the ram stroke, i.e., together with the calibration punch, towards the calibration die. This movement presses the sheet metal preform downwards and positions it securely in the calibration die, for example, by means of a spring, wedge driver, hydraulics, or pneumatics.
  • a relative movement occurs between the calibration punch and the element until the element is finally flush with the calibration punch at the bottom dead center.
  • the element arranged in the calibration die is moved in such a controlled manner, for example via the ram stroke and/or additional control units, which may be driven, for example, by springs, wedge drivers, hydraulics, or pneumatics, such that a defined distance is maintained between the element and the calibration punch during the closing of the calibration tool. This distance is not undercut until the element is fully flush within the calibration die.
  • This defined distance is preferably selected such that no excessively large force acts on the sheet metal component to be calibrated in the area of the element during the closing of the calibration die, and that, for example, the surface of the finished component is not unduly damaged by the element, and/or the calibration process is not unduly hindered, and/or the excess material, for example, in the base, is not unduly deformed. If the element is flush with the calibration die during the ram stroke, no further relative movement can occur between the element and the calibration die, thus forming a closed working surface without a step. In particular, during the closing process, before reaching the lower end position, the element is essentially flush with the working surface of the calibration die.
  • the device comprises a calibration tool with a calibration punch mounted on the press table, a calibration die mounted on the press ram, and a projecting element or optionally several projecting elements, wherein the projecting element is arranged in the calibration punch and is movable relative to the calibration punch.
  • the contour of the calibration punch and the calibration die essentially corresponds to the base, the frame, and the optional flange.
  • the transition areas between the base and frame, and optionally between the frame and flange, are defined by the target geometry of the sheet metal component.
  • the protruding element which is arranged in the calibration die, serves to position the sheet metal preform at a predefined height before upsetting/calibrating it on the calibration die.
  • the protruding element can, for example, extend up to 30 mm, particularly up to 15 mm, or preferably up to 5 mm, from the calibration die, but must not extend more than 0 mm. Positioning at a defined height can advantageously affect the position of the sheet metal preform when the calibration tool closes and, for example, prevent the sheet metal preform from becoming trapped between moving parts of the calibration die, such as when lateral slides are provided.
  • the calibration tool can comprise a calibration die, a calibration die, and a protruding element, or optionally several protruding elements, wherein the protruding element is arranged in the calibration die and is movable relative to the calibration die.
  • the calibration punch is arranged at the bottom and the calibration die at the top of the calibration tool and are movable relative to each other.
  • the element is positioned protruding within the calibration punch and positions the inserted sheet metal preform at a defined height by means of a force-fit connection, for example, using springs, wedge drivers, hydraulics, or pneumatics above the calibration punch.
  • a force-fit connection for example, using springs, wedge drivers, hydraulics, or pneumatics above the calibration punch.
  • the previously protruding element is preferably positioned in its lowest position within the calibration punch in such a way that a closed working surface without a step is created and the element and calibration punch essentially correspond to the geometry of the sheet metal component to be produced.
  • the element which is arranged in the calibration punch by means of a spring, hydraulics, or pneumatics, and projects beyond the effective surface of the calibration punch, can be moved in such a way that the projecting element is preferably flush with the calibration punch before the press stroke reaches bottom dead center. This ensures that the surface of the finished sheet metal component is not unduly damaged by the projecting element during the actual calibration process. is and/or the calibration process is not unduly hindered and/or the excess material introduced into the ground, for example, is unduly deformed.
  • the protruding element or optionally the protruding elements in the calibration punch are combined with a leading element or optionally several leading elements in the calibration die.
  • the arrangement of a protruding element or optionally protruding elements can, analogously, also be implemented in the calibration die for a sheet metal component open upwards in the press position.
  • the combination of a protruding element or optionally several protruding elements in the calibration die can, analogously, be implemented with a leading element or optionally several leading elements in the calibration punch.
  • the device it is integrated into a press line or transfer press. Particularly in the production of mass-produced goods, for example, for products in the automotive industry, sheet metal components are manufactured most economically in press lines or transfer presses.
  • the device can be economically integrated into existing production lines in the form of interchangeable inserts, which include at least one preforming tool and at least one calibration tool. Use of the device in progressive die presses is also conceivable.
  • FIG. 1 A schematic cross-sectional view shows a sequence of an embodiment of a method or device (100) according to the invention.
  • the method according to the invention for manufacturing a sheet metal component (3) comprises at least two steps. Firstly, the method comprises preforming a sheet metal part (1) into a sheet metal preform (2) having in cross-section (Q, Q1.1, Q1.2) a base (2.1), at least one frame (2.2), at least one transition (2.4) between the base (2.1) and the frame (2.2), optionally at least partially a flange (2.3), and optionally at least partially a transition (2.5) between the frame (2.2) and the flange (2.3) in a preforming tool (10), which acts on the sheet metal part (1) with its working surfaces (10.1, 10.2), wherein the sheet metal preform (2) has excess sheet metal material (4) at least partially.
  • a preforming tool (10) which acts on the sheet metal part (1) with its working surfaces (10.1, 10.2), wherein the sheet metal preform (2) has excess sheet metal material (4) at least partially.
  • the process includes finishing the sheet metal preform (2) into a sheet metal component (3) in a calibration tool (20), which acts on the sheet metal preform (2) with its working surfaces (20.1, 20.2) and in which the excess sheet metal material (4) is compressed in the sheet metal plane (E).
  • the sectional views of the preforming tool (10) and calibration tool (20) shown in this example refer to a section in the area of a sheet metal preform end and a sheet metal component end, respectively.
  • the working surfaces (10.1, 10.2) of the preforming tool (10) of the sheet metal preform (2) to be produced are configured in relation to the working surfaces (20.1, 20.2) of the calibration tool (20) of the sheet metal component (3) to be produced such that, when comparing the preforming tool (10) and the calibration tool (20) and considering the difference angle between the two principal axes of inertia (A2, A3) oriented in the same direction with respect to the respective cross-sectional shape, through the centroids of two parallel cross-sectional surfaces (Q1.1, Q1.2, Q2.1, Q2.2) spaced 100 mm apart, a torsional angle difference (tdiff) of at least 0.2° is established.
  • tdiff torsional angle difference
  • the working surfaces (10.1, 10.2) of the preforming tool (10) can be configured in comparison to the working surfaces (20.1, 20.2) of the calibration tool (20) such that in the sheet metal preform (2) to be produced, compared to the sheet metal component (3) to be produced, at least in certain areas a curvature in the longitudinal extent of the sheet metal preform (2) is set which deviates by at least 1% from the curvature in the longitudinal extent of the sheet metal component (3) to be produced.
  • the working surfaces (10.1, 10.2) of the preforming tool (10) can be configured in comparison to the working surfaces (20.1, 20.2) of the calibration tool (20) so that a difference in the flange opening angle (zdiff) of at least 0.5° is set at the same location in the sheet metal preform (2) to be produced compared to the sheet metal component (3) to be produced.
  • a flat sheet (1) is, for example, unwound and cut to length as a defined blank or shaped sheet from a metal coil (not shown) and provided to the further process.
  • the sheet (1) is made of a steel material, preferably a high-strength steel material, for example with a material thickness between 0.5 and 4 mm.
  • a high-strength steel material for example with a material thickness between 0.5 and 4 mm.
  • aluminum materials or other metals can also be used.
  • the sheet metal (1) is first preformed using conventional methods such that the geometry of the sheet metal preform (2) is provided with excess sheet metal material (4) for the subsequent process.
  • the sheet metal preform (2) can be preformed, for example, by crash forming or alternatively by deep drawing with a spaced sheet metal holder or alternatively by deep drawing.
  • the sheet metal preform (2) is produced, for example, in a preforming tool (10), wherein the flat sheet metal (1) is inserted into the open preforming tool (10) by suitable means (not shown here), and in which the working surfaces (10.1, 10.2) of the preforming tool (10) act on the sheet metal (1).
  • the excess sheet material (4) provided at least partially in the sheet metal preform (2) during its manufacture ensures that the excess sheet material (4) required for upsetting/calibration, particularly in the base (2.1) of the sheet metal preform (2), for example in the form of introduced waves, embossments, bulges, or curves, and/or especially in the sides (2.2) and/or in the optional flanges (2.3) of the sheet metal preform (2), for example by extending them, is taken into account in the preforming tool (10).
  • the manufacture of the sheet metal preform (2) is not limited to a single preforming tool (10), but can, depending on the complexity of the sheet metal component (3) to be produced, be carried out in two or more stages or preforming tools (not shown here).
  • the design of the sheet metal preform (2) is characterized by flexibility and offers many possibilities for achieving a suitable sheet metal preform (2) due to geometric freedoms. This sheet metal preform (2) should be geometrically oriented as close as possible to the final geometry of the sheet metal component (3).
  • the sheet metal preform (2) is removed from the preforming tool (10).
  • This preform exhibits springback and/or torsion due to an inhomogeneous, introduced stress state within the preform.
  • compensatory measures have been implemented in the form of modified effective surfaces (10.1, 10.2) compared to the effective surfaces (20.1, 20.2) of the calibration tool (20) to obtain a sheet metal preform (2) that closely approximates the target geometry of the sheet metal component (3). Fluctuations in springback and/or torsion are compensated for in the calibration tool (20), thus eliminating the need for complex correction loops.
  • the sheet metal preform (2) has, at least in some areas in the cross-section (Q), a developed length which is between 0.5% and 6% longer with respect to the developed length of the sheet metal component (3).
  • the sheet metal preform (2) is removed from the preforming tool (10) and still exhibits a deviation from its target geometry caused by various influencing factors.
  • the sheet metal preform (2) is placed into a calibration tool (20), which comprises a calibration punch (21) and a calibration die (22).
  • the calibration tool (20) can include an element (23) which is arranged in the calibration die (22) and is movable relative to the calibration die (22).
  • the inserted sheet metal preform (2) is first fixed or clamped securely in position between the element (23) and the calibration punch (21).
  • the working surfaces (20.1, 20.2) act on the sheet metal preform (2), and by means of superimposed compressive stress, the excess sheet metal material (4) in the sheet plane (E) is compressed, so that the sheet metal preform (2) is formed into a sheet metal component (3) that substantially corresponds to the target geometry.
  • the superimposed compressive stress, or compression in the sheet plane (E) is achieved by acting on the excess material in the sheet metal preform (2) in the form of, for example, straight or wave-shaped extended component cross-sectional segments, while simultaneously locking the sheet metal preform over its edges in the cross-section (Q). This is done, for example, by the locking mechanism (21.1) in the calibration die (21).
  • slides (not shown) can also be arranged in the calibration tool to lock the edges of the sheet metal preform.
  • the torsional angle difference (tdiff) thus corresponds to the angle increment of the difference angle between the principal axes of inertia oriented in the same direction with respect to the cross-sectional shape.
  • (A2, A3) of the effective surfaces (10.1, 10.2) of the preforming tool (10) of the sheet metal preform to be produced (2) in comparison to the effective surfaces (20.1, 20.2) of the calibration tool (20) of the sheet metal component to be produced (3) between the principal axes of inertia (A2, A3) of the effective surfaces (10.1, 10.2) of the preforming tool (10) oriented in the same direction with respect to the cross-section in comparison to the effective surfaces (20.1, 20.2) of the calibration tool (20) in two parallel cross-sections (Q1.1, Q1.2, Q2.1, Q2.2) at a distance of 100 mm.
  • the cross-sections (Q1.1, Q2.1) and (Q1.2, Q2.2) are, for example, congruent, i.e., they are defined at the same location on the sheet metal preform (2) and on the sheet metal component (3), respectively, in the preforming tool (10) and calibration tool (20).
  • the principal axes of inertia (A2, A3) can, for example, be congruent.
  • a sheet metal component (3) made of a steel material with a yield strength of 440 MPa and a thickness of 1.5 mm was first designed methodically using an FE simulation and subsequently implemented in the tooling.
  • High-strength and ultra-high-strength steel materials have shown in the past that the sheet metal preforms produced using the previous method deviate from the desired target geometry to such an extent due to their tendency towards pronounced, unwanted springback and/or torsion effects that neither a secure insertion into the calibration tool nor a satisfactory calibration result can be achieved.
  • the difference between the sheet metal preform and the target geometry relates in particular to excessive springback-induced torsion of the entire sheet metal preform (2').
  • Figure 2 shows the sheet metal preform that would result if a sheet metal preform (2') were conventionally produced from a higher-strength steel material.
  • the torsion at the conventionally produced sheet metal preform is very pronounced compared to the sheet metal component end of the finished sheet metal component (3) and cannot be sufficiently reduced or reliably processed further in subsequent processes.
  • the working surfaces (10.1, 10.2) of the preforming tool (10) of the sheet metal preform (2) By designing the working surfaces (10.1, 10.2) of the preforming tool (10) of the sheet metal preform (2) to be produced in comparison to the working surfaces (20.1, 20.2) of the calibration tool (20) of the sheet metal component (3) to be produced, with a torsional angle difference (tdiff) of at least 0.2° set between the principal axes of inertia (A2, A3) of the working surfaces (10.1, 10.2) of the preforming tool (10) and the working surfaces (20.1, 20.2) of the calibration tool (20) at a distance of 100 mm in two parallel cross-sections (Q1.1, Q1.2, Q2.1, Q2.2) that are oriented the same with respect to the cross-section, the unwanted springback and/or torsion of the sheet metal preform (2) can be substantially compensated.
  • tdiff torsional angle difference
  • a counter-torsion can be set up and implemented on the tooling side to counter the conventionally produced alignment of the sheet metal preform (2'), so that in the Execution according to Figure 2 A torsional angle difference (tdiff) of 5° is set to preform a sheet metal preform (2) that closely approximates the target geometry.
  • tdiff torsional angle difference
  • the working surfaces (10.1, 10.2) of the preforming tool (10) can be configured, in comparison to the working surfaces (20.1, 20.2) of the calibration tool (20), to ensure that a flange opening angle difference (zdiff) of at least 0.5° is set in the sheet metal preform (2) to be produced compared to the sheet metal component (3).
  • zdiff flange opening angle difference
  • Figure 2 This approach was also taken into account with a frame opening angle difference (zdiff) of 5°, in particular to prevent undercutting in the preforming tool (10).
  • flangeless sheet metal components can also be produced with substantially reduced springback.
  • the tools (10, 20) can be designed as interchangeable tools and used in a production line, especially in a press line, transfer press or progressive die press.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)

Claims (11)

  1. Procédé de fabrication d'un composant en tôle (3), le procédé comprenant au moins deux étapes :
    - préfiguration d'une tôle (1) en une préforme de tôle (2) présentant, en section transversale (Q), un fond (2.1), au moins un rebord (2.2), au moins une transition (2.4) entre le fond (2.1) et le rebord (2.2), éventuellement, au moins en partie, une bride (2.3) et éventuellement, au moins en partie, une transition (2.5) entre le rebord (2.2) et bride (2.3) dans un outil de préformage (10) qui agit avec ses surfaces actives (10.1, 10.2) sur la tôle (1), la préforme de tôle (2) présentant au moins par endroits un excédent de matériau de tôle (4) ; et
    - le formage final de la préforme de tôle (2) en un composant en tôle (3) dans un outil de calibrage (20) qui agit avec ses surfaces actives (20.1, 20.2) sur la préforme de tôle (2) et dans lequel le matériau de tôle excédentaire (4) est refoulé dans le plan de la tôle (E) ;
    caractérisé en ce que
    - les surfaces actives (10.1, 10.2) de l'outil de préformage (10) de la préforme en tôle (2) à produire sont disposées, par rapport aux surfaces actives (20.1, 20.2) de l'outil de calibrage (20) de la pièce en tôle (3) à produire (3) de telle sorte que, lorsque l'on compare l'outil de préformage (10) et l'outil de calibrage (20) en observant l'angle différentiel entre les deux axes d'inertie principaux (A2, A3) orientés de manière identique par rapport à la forme de la section transversale respective à travers les centres de gravité de deux surfaces de section transversale parallèles (Q1.1, Q1.2, Q2.1, Q2.2) à une distance de 100 mm de la fente d'outil entourée par les surfaces actives respectives (10.1, 10.2, 20.1, 20.2) est réglé à une valeur d'au moins 0,2°, la différence d'angle de torsion (tdiff) correspondant à l'incrément angulaire de l'angle différentiel entre les axes d'inertie principaux (A2, A3) orientés de manière identique par rapport à la forme de la section transversale ; et/ou
    - les surfaces actives (10.1, 10.2) de l'outil de préformage (10) sont disposées de telle sorte que, par rapport aux surfaces actives (20.1, 20.2) de l'outil de calibrage (20) sont conçues de telle sorte que, dans la préforme de tôle (2) à produire, par rapport à la pièce en tôle (3) à produire, une courbure dans l'extension longitudinale de la préforme de tôle (2) est réglée au moins par endroits qui s'écarte d'au moins 1 % de la courbure dans le sens longitudinal de la pièce en tôle (3) à produire, la courbure variable d'une pièce étant définie comme la courbure d'une B-spline imaginaire qui est définie par les centres de gravité des sections transversales locales, c'est-à-dire les points d'intersection des axes principaux des sections transversales.
  2. Procédé selon la revendication 1, dans lequel les surfaces actives (10.1, 10.2) de l'outil de préformage (10) sont agencées par rapport aux surfaces actives (20.1, 20.2) de l'outil de calibrage (20) sont agencées de telle sorte que, dans la préforme de tôle (2) à produire, une différence d'angle d'ouverture du cadre (zdiff) d'au moins 0,5° est réglée au même endroit par rapport à la pièce en tôle (3) à produire.
  3. Procédé selon la revendication 1 ou 2, dans lequel on utilise une tôle d'acier ayant une limite d'élasticité Re d'au moins 400 MPa.
  4. Procédé selon l'une des revendications précédentes, dans lequel l'outil de calibrage (20) comprend un poinçon de calibrage (21), une matrice de calibrage (22) et un élément (23) ou, en option, plusieurs éléments, l'élément (23) étant disposé dans la matrice de calibrage (22) et déplacé par rapport à la matrice de calibrage (22).
  5. Procédé selon la revendication 4, dans lequel le poinçon de calibrage (21) est disposé en bas et la matrice de calibrage (22) en haut dans l'outil de calibrage (20).
  6. Procédé selon l'une des revendications 1 à 4, l'outil de calibrage (20) comprenant un poinçon de calibrage (21), une matrice de calibrage (22) et un élément (23) ou, en option, plusieurs éléments, l'élément (23) étant disposé dans le poinçon de calibrage (21) et déplacé par rapport au poinçon de calibrage (21).
  7. Procédé selon la revendication 6, dans lequel le poinçon de calibrage (21) est disposé en haut et la matrice de calibrage (22) en bas dans l'outil de calibrage (20).
  8. Procédé selon la revendication 4, dans lequel l'élément ou, en option, plusieurs éléments disposés dans la matrice de calibrage sont déplacés de manière commandée par la course du coulisseau et/ou des unités de commande supplémentaires () de telle sorte qu'une distance définie entre l'élément et le poinçon de calibrage est obtenue pendant la fermeture de l'outil de calibrage.
  9. Procédé selon la revendication 8, dans lequel, pendant la fermeture, avant d'atteindre la position finale inférieure, l'élément se termine essentiellement à fleur de la surface active de la matrice de calibrage.
  10. Procédé selon la revendication 6, dans lequel l'élément ou, en option, plusieurs éléments disposés dans le poinçon de calibrage sont déplacés de manière commandée par la course du coulisseau et/ou des unités de commande supplémentaires de telle sorte qu'une distance définie entre l'élément et la matrice de calibrage est obtenue pendant la fermeture de l'outil de calibrage.
  11. Procédé selon la revendication 10, dans lequel l'élément, pendant la fermeture, avant d'atteindre la position finale inférieure, affleure essentiellement la surface active de la matrice de calibrage.
EP22765467.0A 2021-08-20 2022-08-12 Procédé de fabrication de pièces en tôle et dispositif pour la mise en oeuvre de ce procédé Active EP4387783B1 (fr)

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PCT/EP2022/072635 WO2023020950A1 (fr) 2021-08-20 2022-08-12 Procédé de fabrication de pièces en tôle et dispositif pour la mise en oeuvre de ce procédé

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JP4757820B2 (ja) * 2007-03-14 2011-08-24 新日本製鐵株式会社 形状凍結性に優れる多段プレス成形方法
DE102007059251A1 (de) 2007-12-07 2009-06-10 Thyssenkrupp Steel Ag Herstellverfahren hoch maßhaltiger Halbschalen
DE102008037612B4 (de) 2008-11-28 2014-01-23 Thyssenkrupp Steel Europe Ag Verfahren und Werkzeugsatz zur Herstellung von flanschbehafteten, hoch maßhaltigen und tiefgezogenen Halbschalen
DE102009059197A1 (de) 2009-12-17 2011-06-22 ThyssenKrupp Steel Europe AG, 47166 Verfahren und Vorrichtung zur Herstellung eines Halbschalenteils
DE102013103612B8 (de) 2013-04-10 2023-12-28 Thyssenkrupp Steel Europe Ag Verfahren und Stauchwerkzeug zur Herstellung von hoch maßhaltigen Halbschalen
DE102013103751B4 (de) 2013-04-15 2025-03-27 Thyssenkrupp Steel Europe Ag Verfahren zur Herstellung von hochmaßhaltigen Halbschalen und Vorrichtung zur Herstellung einer Halbschale
KR101869177B1 (ko) * 2013-12-26 2018-06-19 신닛테츠스미킨 카부시키카이샤 모자형 단면 부품의 제조 방법
JP5861749B1 (ja) * 2014-07-30 2016-02-16 Ｊｆｅスチール株式会社 プレス成形方法
BR112017022630A2 (pt) * 2015-04-22 2018-07-17 Nippon Steel & Sumitomo Metal Corporation método para produção de produto moldado em prensa, produto moldado em prensa, matriz e dispositivo de prensagem
EP3272438B1 (fr) * 2015-04-22 2020-07-22 Nippon Steel Corporation Procédé permettant de produire un produit moulé à la presse, produit moulé à la presse et dispositif de pressage
DE102016118418A1 (de) 2016-09-29 2018-03-29 Thyssenkrupp Ag Verfahren zur Herstellung eines geformten Bauteils mit einem maßhaltigen Zargenbereich
JP6515961B2 (ja) * 2017-08-02 2019-05-22 Ｊｆｅスチール株式会社 プレス成形品の製造方法
DE102018210174A1 (de) 2018-06-22 2019-12-24 Thyssenkrupp Ag Verfahren zur Herstellung eines Trägers und eines Leiter- oder Kastenrahmens
JP6733773B1 (ja) * 2019-04-22 2020-08-05 Ｊｆｅスチール株式会社 プレス成形方法
PT3771502T (pt) 2019-07-29 2022-02-03 Gestamp Aveiro Ind De Acessorios De Automoveis S A Método e dispositivo de conformação para produzir um componente de chapa metálica com flanges

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US20240335870A1 (en) 2024-10-10
EP4387783A1 (fr) 2024-06-26
ES3062800T3 (en) 2026-04-14

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