US20190193136A1

US20190193136A1 - Method and Device for Producing Formed, in Particular Flanged, Sheet Metal Components

Info

Publication number: US20190193136A1
Application number: US16/330,508
Authority: US
Inventors: Thomas Flehmig; Martin Kibben; Daniel Nierhoff
Original assignee: ThyssenKrupp Steel Europe AG; ThyssenKrupp AG
Current assignee: ThyssenKrupp Steel Europe AG; ThyssenKrupp AG
Priority date: 2016-09-07
Filing date: 2017-08-30
Publication date: 2019-06-27
Also published as: CN109689243A; DE102016116758A1; EP3509772A1; MX2019002585A; WO2018046356A1; CN109689243B

Abstract

A method for producing a formed, flanged component is disclosed. The method includes the steps of: preforming a workpiece a preformed component; and calibrating the preformed component to a substantially completely formed component. The method strengthens the reinforcement in the component and widens the spectrum of application to components in particular, to tub-shaped components. The calibrating of the preformed component to the completely formed component includes stretching the preformed component at least in portions. The present disclosure relates further to a device for producing a formed, flanged component.

Description

The present invention relates to a method for producing a formed, in particular flanged, sheet-metal component, the method comprising the following steps of preforming a workpiece to a preformed component, and calibrating the preformed component to a substantially completely formed component. The invention relates furthermore to a device for producing a formed, in particular flanged, sheet-metal component, in particular for carrying out a method according to the invention, having one or a plurality of preforming tools for preforming a workpiece to a preformed component, and having one or a plurality of calibrating tools for calibrating the preformed component to a substantially completely formed component.
Components which are produced by a sheet-metal forming, for example deep-drawn components, typically require a final peripheral trimming in which surplus regions of the, for example deep-drawn, component are cut off. In the case of flanged parts, this can be performed, for example, by way of one or a plurality of trimming tools which in the desired manner cut the flange partially or entirely from above or obliquely. In the case of flangeless parts, however, the trimming is already substantially more complex because said surplus regions have to be cut from the side, for example directed by way of tapered slides. The trimming operations are however disadvantageous to the extent that the trimming in most instances requires one or even a plurality of separate and often maintenance-intensive operations which moreover often require a dedicated tooling technology and a dedicated logistics system. Moreover, the cut-off regions increase the scrappage proportion, on account of which further costs are created. In the case of components which are formed by means of edge-bending or embossing, for example, the final peripheral trimming can also be dispensed with. Various approaches have been pursued so as to shorten at least the process chain, said approaches inter-alia integrating the flange trimming in the last shape-imparting operation, for example the deep-drawing operation. Appreciable cost savings can indeed already be thus achieved, but some disadvantages such as, the occurrence of cutting waste, the construction of complicated tools, complex testing, unintentional rebounding effects, restricted dimensional accuracy, and the susceptibility in relation to process interruptions do continue to remain.
For this reason, methods and devices are proposed for rendering obsolete, or heavily reducing, respectively, the peripheral trimming of in particular U-shaped or hat-profile-shaped components.
The German publication of the application DE 10 2007 059 251 A1 thus describes a method for producing with a minor complexity in terms of technical equipment dimensionally highly accurate half-shells having a base region and a side-plate. To this end, a preformed half-shell is initially formed from a blank. The entire cross section of the preformed half-shell, by virtue of the geometric shape thereof, has surplus blank material. During the forming of the preformed half-shell to the final shape thereof by way of at least one further pressing procedure, the entire cross section is compressed to the finished half-shell, and the finished half-shell has an enlarged wall thickness across the entire cross section.
The German publication of the application DE 10 2008 037 612 A1 likewise describes a method for producing dimensionally highly accurate half-shells having a base region, a side-plate region, and a flange region, wherein a preformed half-shell is initially formed from a blank, said preformed half-shell subsequently being formed to the finally formed half-shell. The preformed half-shell, by virtue of the geometric shape thereof, has surplus blank material. On account of the surplus material, the preformed half-shell while being formed to the final shape thereof by at least one further pressing procedure, the half-shell is compressed to the finally formed half-shell. The preformed half-shell comprises the surplus blank material in the transition region between the side-plate region and the flange region.
The German publication of the application DE 10 2009 059 197 A1 describes a method for producing a half-shell part by way of a drawing die and a drawing swage. A cost-effective production that is reliable in terms of the process is achieved in that in a single operating step the drawing die is moved into the drawing swage, a blank is preformed to an unmachined sheet-metal part having at least one base portion, at least one side-plate portion, and optionally a flange portion, wherein during the preforming using the drawing die a material surplus is incorporated either in the base portion and the site-plate portion, or the optional flanged portion of the unmachined sheet-metal part, and the unmachined sheet-metal part is completely formed and calibrated to a half-shell part.
The German publication of the application DE 10 2013 103 612 A1 likewise describes a method for producing dimensionally highly accurate half-shells, wherein a half-shell preformed from a blank is formed to a finished half-shell, and the preformed half-shell, by virtue of the geometric shape thereof, comprises surplus blank material. The half-shell is compressed to the finally shaped half-shell in a compressing tool. It is provided that the size of the compression gap during the closing of the compressing tool is reduced to the nominal wall thickness of the side-plate of the preformed half-shell.
The German publication of the application DE 10 2013 103 751 A1 describes a method for producing dimensionally highly accurate half-shells from a cut-to-size blank, wherein the half-shell is preformed in a first swage, and wherein the preformed half-shell is subsequently finally formed in a second swage, in particular in a calibrating tool. The blank, while taking into account the desired final shape of the preformed or finally formed half-shell respectively, prior to forming is cut-to size having a positive dimensional deviation in the predefined tolerance range, and the swage base of the first swage is moved relative to the swage bearing face so as to guide the blank during forming.
It is a common feature of the approaches described that a preform which indeed comes as close as possible to the final shape or completed shape of the component is generated in a first or a plurality (of first) method steps, with the difference however, that defined material reserves are incorporated in the component portion such as the flange, the side-plate, the transition region between the flange and the side-plate and/or the base, said material reserves in a second method step again being reverse-formed by a special compressing of the entire part during the calibrating.
This known method does indeed eliminate the above-mentioned disadvantages, but in itself has undesirable side-effects.
It has been demonstrated, on the one hand, that the compressing of the sheet metal can in part produce slight corrugations in the completely formed component when the spacing between the compressing swage and the compressing die when calibrating does not correspond exactly to the sheet-metal thickness. These corrugations can represent a visual or even dimensional fault.
It has furthermore been demonstrated that the local sheet-metal thicknesses can also vary on account of the compressing procedure. Corrugations which likewise can represent visual deficiencies are created on account thereof. Attempts to date are directed toward reducing as far as possible the compressed proportions.
On the other hand, the compressing of the preformed component, above all in the case of large parts, wall thicknesses, or/and high-strength steels, requires very massive tools so as to avoid any undesirable deformation. Very high press forces which can exceed existing press capacities and thus lead to limitations in the implementation capability are often also required herein.
As has been demonstrated in simulations, by way of the methods already mentioned it is moreover possible to produce in particular tub-type or pot-type components with difficulty, since the method mentioned for generating the preform in terms of process technology is to be managed such that, if at all or only very minor process variations by way of which friction conditions are created and changes to the typical process variables such as friction and blank-holder force are heavily limited. When such tub-type parts are subjected to said procedure, the traction exerted on the side-plates is insufficient, and the part at this location is imparted more or less intense folds which however cannot again be smoothed to the desirable extent in the calibration step.
Furthermore, the minimization in terms of material in the case of the methods described above is not yet exhausted since the components have to be produced with a material allowance of approximately 1 to 3% in addition to the actual component designed (CAD part). Said components are thus also heavier at least by this amount than parts that are made by conventional deep-drawing.
Lastly, the solidification potential of the material is not yet exhausted in the case of the aforementioned method. This may indeed have advantages in terms of the crash behavior of the component, but is not desirable for all components and is not always optimal.
Against this background, the invention is based on the object of specifying a generic method and a generic device, wherein the disadvantages mentioned at the outset are minimized or even eliminated, that is to say that the solidification in the component is in particular stronger and the spectrum of application is widened to components which by way of the parameters of the methods from the prior art have to date not being able to be drawn without folds, thus to in particular tube-shaped or pot-shaped components, in particular having a small sheet-metal thickness.
The object in the case of a generic method is achieved in that the calibrating of the preformed component to the completely formed component comprises at least in portions stretching the preformed component.
It has been demonstrated that dimensionally highly accurate components which are substantially close to the final shape can be made if the calibrating of the preformed component to the completely formed component is not limited to one compressing procedure but moreover stretching of the preformed component is carried out. It has been demonstrated in particular that material elevations that have been incorporated during the preforming by stretching can be equalized or smooth again, respectively. To this extent, a component which does not require any or only very minor peripheral trimming can be made in this way. On account of the stretched regions moreover at least in part not necessarily having to be compressed, a force that is lower as compared to the methods according to the prior art is moreover sufficient. Stretching is understood to mean that a direction independent plastic deformation is performed and, on account thereof, a fresh alignment of the non-homogenous stress state of the preform is achieved and, on account thereof, dimensionally highly accurate components which are as close as possible to the final shape can be generated.
The method is particularly advantageous in the case of tub-shaped, pot-shaped, or cup-shaped components, since said components have not been accessible, or not economically accessible, to the methods described to date. The component therefore preferably has a base region, a side-plate region, and/or a flange region. The side-plate region runs so as to be oblique or substantially perpendicular to the base region and/or to the site-plate region, for example.
The workpiece is, for example, a substantially flat blank. The workpiece is preferably produced from one or a plurality of steel materials. Aluminum materials or other metals can alternatively be used.
The production of the preform herein can be produced in one or a plurality of steps by means of shape-imparting methods combined in an arbitrary manner. The preforming can comprise a deep-drawing-type shaping step, for example. In particular, multi-staged shaping, comprising to be embossing of the base established and raising the side-plates to be established, or optionally folding back of the flanges to be established, respectively, can also be performed. Any arbitrary combinations of edge-bending and/or bending and/or embossing are also conceivable. The deep-drawing carried out for the preforming, for example, is carried out in one stage or multiple stage, for example. The preformed component obtained by the preforming can in particular be considered to be a component that is as close to the final shape as possible and which corresponds as well as possible to the envisaged geometry of the completed part, while taking into account given parameters such as the rebounding and primary-forming capability of the material used.
Calibrating can in particular be understood to be complete forming or final forming of the preformed component, this being achievable, for example, by way of one or a plurality of pressing procedures. The substantially completely formed component to this extent can be understood to be a finally formed component. However, it is possible that the substantially completely formed component can be subjected to even further processing steps that modify the component, such as an incorporation of attachment holes or a (minor) trimming procedure. However, the aspiration is to design the calibrating mold in such a manner that no further forming steps are required.
The preforming and the calibrating described are preferably performed successively. However, it is also conceivable that there is a temporal overlap between the preforming and the calibrating.
According to one design embodiment of the method according to the invention a region, in particular a side-plate region, of the preformed component is configured so as to have a material deficiency in relation to the completely formed component. It has been demonstrated that, as opposed to the previous approaches in the prior art, the preformed component does not have to be equipped with an additional material reserves (material surplus) so as to achieve a sufficient dimensional accuracy. Rather, the method according to the invention departs therefrom and provides that a material deficiency is provided in portions. A material deficiency herein is understood that the flat projection of the sheet metal in local regions in the preform to be produced is smaller than the corresponding area in the completely formed component. The material during the calibration is stretched in a corresponding manner, wherein the material deficiency in the area is equalized by a reduction in the material thickness. A material deficiency as compared to the completely formed component has proven advantageous in particular in the side-plate region. Alternatively or additionally, a base region of the preformed component can also be configured so as to have a material deficiency, if required. Counter to expectations, a sufficiently strong and dimensionally accurate component can be made despite the material deficiency.
According to one design embodiment of the method according to the invention a region, in particular a side-plate region, of the preformed component, in terms of a geometric size, is dimensioned so as to be smaller in comparison to the substantially completely formed component. On account thereof, a material deficiency in the respective region can be advantageously provided with any major complexity in terms of process technology. For example, the side-plate region of the preformed component is dimensioned so as to be smaller in terms of the circumference. In other words, the preformed component has a smaller internal circumference than the substantially completely formed component. Alternatively or additionally, the base region can be dimensioned so as to be smaller, if required, for example in terms of the diameter thereof. For example, the region in terms of the geometric size is dimensioned so as to be approximately 0.1% to 10%, in particular approximately 1 to 10%, smaller.
According to one design embodiment of the method according to the invention, material elevations are permitted while preforming the workpiece to the preformed component (for example by deep-drawing). As opposed to the prior art, it is thus not attempted to suppress any material elevations, for example by incorporating tensile stresses. Rather, said material elevations are now utilized in order to produce a dimensionally accurate component by way of reduced pressing forces. For example, the material elevations resulting in the production of the preform are configured so as to be in the shape of corrugations and/or falls. For example, the material elevations extend substantially in the radial direction or in a direction deviating therefrom. Material elevations during the preforming are created in the flange region, in the side-plate region, and/or in the base region, for example.
According to one design embodiment of the method according to the invention, the material elevations are permitted by providing a (air) gap and/or a blank-holder spacing in the region of the material elevation. The configuration of a material elevation can be advantageously integrated in the exemplary press-based deep-drawing by the exemplary provision of a gap or a plank-holder spacing of the tool (preforming tool) used. It has been demonstrated that the configuration of the material elevations can be managed in a controlled manner by the exemplary provision of a gap or a blank-holder spacing. The gap is configured, for example, between a preforming swage and the preforming die. For example, the gap, when viewed in the cross section, is more than 0.1 times, preferably more than 0.3 times, particularly preferably more than 0.5 times, the sheet-metal thickness. However, in order not to permit any uncontrolled material elevations, the gap is not more than 10 times, preferably not more than 7 times, preferably not more than 5 times, the sheet-metal thickness, for example.
According to one design embodiment of the method according to the invention the material elevations are incorporated in a targeted manner by way of the preforming tool or the preforming tools. It is thus advantageously possible for such preforms which, as a consequence of the geometric design thereof, have an increased tendency toward forming folds to also be produced by a reliable process. Such components with a tendency toward folding are such also rendered accessible to the method according to the invention by way of material elevations that are incorporated in a targeted manner.
According to one design embodiment of the method according to the invention the material elevations are substantially free of material thickenings. For example, the material elevations, when viewed in the cross section, comprise only geometries in the shape of corrugations and/or folds, without the sheet-metal thickness being varied in this region. It has been demonstrated that the material thickenings can no longer be sufficiently eliminated by calibrating. Moreover, no additional pressing forces are required for the forming in the absence of any substantial material thickening.
According to one design embodiment of the method according to the invention the material elevations are ironed by stretching the preformed component. In particular when the material elevations are provided in the side-plate region, the material elevations are preferably ironed in the circumferential direction. Material from the side-plate region and/or the base region is used herein, for example. It has been demonstrated that material elevations, despite being permitted, can again be eliminated by the stretching, without this being visually disadvantageous in terms of the substantially completely formed component.
According to one design embodiment of the method according to the invention a region, in particular a side-plate region or a flange region, of the preformed component, in terms of the geometric size, is dimensioned so as to be larger as compared to the substantially completely formed component. For example, the side-plate region has a greater length (the preformed component thus having a greater height) as compared to the substantially completely formed component. For example, the flange region has a greater length (the flange of the preformed component thus having a greater radial extent) as compared to the substantially completely formed component. This enables additional compressing of the preformed component during the calibrating, this additionally further increasing the strength and the dimensional accuracy of the component without, however, exceeding the available pressing forces.
According to one design embodiment of the method according to the invention the calibrating of the preformed component to the substantially completely formed component comprises at least in regions compressing the preformed component. As has already been explained, the strength and the dimensional accuracy of the component can be increased by compressing. For example, the material of the flange regions is at least in regions compressed. The material herein is provided by the described material elevations in the flange region or by the described larger dimensioning (greater length) of the flange region. For example, the material of the side-plate region is at least in regions compressed. The material herein is in particular provided by the described larger dimensioning (greater length) of the side-plate region. The compressing is subsequent to the stretching, for example.
Despite the additional compressing, regions of the preformed component are however preferably only stretched but not compressed in the method.
According to one design embodiment of the method according to the invention the preformed component by way of the calibrating is subjected to a plastic flow procedure in substantially the entire component or only in portions of the component. Stretching and/or compressing is thus preferably performed in the side-plate region, compressing is preferably performed in the flange region, and pressing is preferably performed in the base region. A dimensionally very accurate component having substantially minor or no rebounding deviations is achieved on account thereof.
The object mentioned at the outset in the case of a generic device is moreover achieved in that the preforming tool and the calibrating tool are specified in such a manner that the calibrating of the preformed component to the substantially completely formed component comprises at least in regions stretching the preformed component. This can be achieved, for example, by a corresponding dimensioning of the tool parts (for example of the tool dies and/or the tool swages).
As has already been explained at the outset, dimensionally very accurate, completely formed components can be made by the calibrating of the preformed component to the substantially completely formed component, said calibrating comprising stretching the preformed component. It has been demonstrated herein that material elevations incorporated during the preforming can be equalized by the stretching such that a visually non-compromised component can be provided. The calibrating can furthermore be achieved by way of a lower force and if at all or only minor peripheral trimming is required.
In order for the material elevations to be configured in a controlled manner, according to one design embodiment of the device according to the invention the preforming tool, while preforming the workpiece to the preformed component, is configured for permitting material elevations (for example by deep-drawing) in particular by means of a gap for example that remains in the closed state and/or of a blank holder spacing and/or of the geometric design of the preforming tool/the preforming tools. The gap is preferably configured between tool halves or tool parts of the preforming tool.
According to one design embodiment of the device according to the invention the preforming tool comprises a preforming die and the preforming swage, and the gap at least in portions is for example configured at least between the preforming die and the preforming swage. This enables in particular a controlled configuring of material elevations in the side-plate region. When the material elevations are permitted, for example, by means of a blank-holders spacing, the preforming tool preferably comprises at least one preforming swage and one preforming blank holder, wherein the preforming blank holder during the preforming is kept at a spacing from the preforming swage that is larger than the sheet-metal thickness.
The preforming swage preferably comprises a first (outer) preforming swage portion and a second (inner) preforming swage portion which is movable relative to said first (outer) preforming swage portion and which forms the preforming swage base. This during the preforming enables an impingement with a force that is individual and temporally adapted for the different regions of the component (in particular of the base region as compared to the remaining regions). The workpiece can in particular be clamped or embossed between the preforming die and the preforming swage base, and can be moved into the first preforming swage portion by the preforming die and the preforming swage base.
According to one design embodiment of the device according to the invention the calibrating tool comprises a calibrating die and a calibrating swage, wherein the calibrating die comprises a first (outer) calibrating die portion and a second (inner) calibrating die portion which is movable relative to said first (outer) calibrating die portion and which forms the calibrating die base, and/or wherein the calibrating swage comprises a first (outer) calibrating swage portion and a second (inner) calibrating swage portion which is movable relative to said first (outer) calibrating swage portion and which forms the calibrating swage base. This during the preforming enables an impingement with a force that is individual and temporally adapted for the different regions of the component (in particular of the base region as compared to the remaining regions). Moreover, the calibrating can advantageously be carried out in particular within only one calibrating tool.
The device is preferably specified in such a manner that the calibrating die base and the calibrating swage base are spaced apart during the stretching, this in particular enabling a material flow from the base region into the side-plate region.
In terms of further design embodiments of the device according to the invention, reference is made to the explanations pertaining to the method according to the invention.
By way of the preceding and following description of method steps according to preferred embodiments of the method, corresponding means for carrying out the method steps by way of preferred embodiments of the device are also intended to be disclosed. The corresponding method step is likewise intended to be disclosed by way of the disclosure of means for carrying out a method step.

The invention is furthermore to be explained in more detail by means of an exemplary embodiment in conjunction with the drawing in which:

FIGS. 1 to 4 show an exemplary embodiment of a preforming tool according to the invention for carrying out an exemplary embodiment of preforming according to the invention;

FIG. 5 shows an exemplary embodiment of a preformed component;

FIGS. 6 10 show an exemplary embodiment of a calibrating tool according to the invention for carrying out an exemplary embodiment of calibrating according to the invention; and

FIG. 11 shows an exemplary embodiment of a substantially completely formed component.

FIGS. 1 to 4 initially show an exemplary embodiment of a preforming tool 1 according to the invention. The exemplary preforming tool 1, conjointly with the exemplary calibrating tool 2 (cf. FIGS. 6 to 10), forms an exemplary embodiment of a device according to the invention. An exemplary embodiment of preforming according to the invention can be carried out by way of the preforming tool 1. It is likewise possible for a plurality of individual preforming sub-tools to also be provided if required (when a plurality of preforming operations are provided).
A workpiece 3 a, here a flat steel sheet, is initially placed into the preforming tool 1 and optionally positionally fixed therein (FIG. 1). The preforming tool 1 comprises a preforming blank holder 4, a preforming swage 6, and the preforming die 8. The preforming swage 6 moreover comprises a first, outer preforming swage portion 6 a which inter alia provides a preforming swage bearing, and a second inner preforming swage portion 6 b or preforming swage base, which is movable relative to said first, outer preforming swage portion 6 a. The preforming swage base 6 b herein is lifted to the height level of the workpiece 3 a.
The individual tool parts of the preforming tool 1 herein are conceived for being received in a press. To the extent that no further auxiliary drives are used, the preforming die 8 stands for example on a press base plate, the preforming blank holder 4 is driven, for example by mandrels of the lower cushion, the preforming swage base 6 b is driven, for example, by mandrels of the upper cushion, and the first preforming swage portion 6 a is driven, for example, by a die plate of the press. However, the drives of the upper cushion and the lower cushion as well as the swage and the die can also be reversed in an individual case.
The preforming die 8 and the preforming blank holder 4 are subsequently lowered onto the workpiece 3 a (FIG. 2). The workpiece 3 a can be embossed between the preforming die 8 and the preforming swage base 6 b, while the preforming blank holder 4 however remains spaced apart from the workpiece 3 a. The preforming blank holder 4 is spaced apart from the workpiece 3 a so far that a constant blank holder-spacing which is larger than or equal to the workpiece thickness results. Deep-drawing, for example, is now performed, wherein the preforming die 8 and the preforming swage base 6 b conjointly move into the preforming swage 6 a and herein form/preform the workpiece 3 a to a preformed component 3 b (FIG. 3). Alternatively, the so-called embossing including raising can be applied, wherein the blank holder can also be entirely omitted. In the embossing including raising, the workpiece (minimum shape blank) which is fixed in the defined and accurately reproducible position thereof previously determined by simulation or experimenting is initially embossed by way of the lifted preforming swage base 6 b, and said assembly of the three parts is then pushed into the preforming swage 6 a without blank holders.
The preforming die 8 and the preforming swage 6 presently are mutually adapted in such a manner that a gap 10 is formed (FIG. 4). It is usually attempted to keep the gap in the tool as small as possible, usually so as to be not larger than 0.1 times the workpiece thickness. The gap 10 here is however preferably 0.5 times to 5 times the workpiece thickness.
On account thereof, radially or otherwise directed corrugations 12 are permitted in the side-plated region of the preformed component 3 b (and selectively also in the base region and/or in the flange region) when preforming (cf. FIG. 5). This in particular in the case of preformed components having an oblique or almost perpendicular site-plate region is in particular achieved in that the traction is absent on account of the deceleration of the flange due to the non-existent or spaced-apart preforming blank holder 4.
On account of a gap 10 and a blank-holder spacing being provided which can assume a multiple of the sheet-metal thickness, the corrugations 12 are not flattened by way of contact with the tool parts 6 a, 8 such that no uncontrollable thickenings are created.
As is schematically illustrated in FIG. 5, a preformed component 3 b is present as the result of the preforming, the site-plate region of said preformed component 3 b, when viewed in the circumferential direction, being smaller by a specific dimension (for example by 0.1 to 10%) than is predefined by the desired completely formed component, and said preformed component 3 b in the side-plate region, in the base region, and/or in the flange region potentially preferably having radial corrugations 12 which have no or hardly any thickenings. In the present example, the side-plate region in particular (and also the base region, if required) of the preformed component 3 b is/are thus not equipped with a material surplus but with a material deficiency as compared to the completely formed component. However, the height of the site-plate region of the preformed component 3 b is somewhat greater than is predefined by the completely formed component. Additionally or alternatively, the length of the flange region of the preformed component 3 b can be greater than is predefined by the completely formed component.
As will be described in more detail in the context of FIGS. 6 to 10, the preformed component 3 b is subsequently placed into the calibrating tool 2 and calibrated to a completely formed component 3 c (FIG. 11).
The calibrating tool 2 comprises a calibrating die 20 and the calibrating swage 22. The calibrating die 20 has a first outer calibrating die portion 20 a and a second inner calibrating die portion 20 b or calibrating die base which is movable relative to said first outer calibrating die portion 20 a. The calibrating swage 22 comprises a first outer calibrating swage portion 22 a and a second inner calibrating swage portion 22 b or calibrating swage base which is movable relative to said first outer calibrating swage portion 22 a. The first calibrating swage portion 22 a in the region of the flange of the preformed component 3 b furthermore includes a lowered feature 24 such that a shoulder 26 protruding on the calibrating die 22 fits thereinto in form-fitting manner.
The calibrating die 20 and the calibrating swage 22 of the calibrating tool 2 are embodied such that the completely formed component in the terminal position is completely defined by the intervening cavity.
The calibrating tool 2 is also conceived for being received in a press. To the extent that no auxiliary drives are used, the calibrating die base 20 b is driven, for example, by mandrels of the lower cushion, the calibrating swage base 22 b is driven, for example, by the mandrels of the upper cushion. The first calibrating swage portion 22 a is driven, for example, by the die plate of the press, the first calibrating die portion 20 a stands, for example, on the press base plate. The upper cushion and the lower cushion, as well as the swage and the die, can also be reversed in an individual case.
As is illustrated in FIG. 6, the preformed component 3 b is initially moved in a defined position onto the lifted calibrating swage base 22 b or part of the calibrating swage portion 22 a and there is positionally fixed in a suitable manner, for example by way of guide pins or mold elements. The calibrating die base 20 b subsequently moves toward the calibrating swage base 22 b and herein partially presses the base region of the preformed component 3 b (FIG. 7). The aforementioned however by way of a minor, defined spacing of approximately 0.5 times to 5 times the workpiece thickness. When moving onward, the two faces 20 b, 20 b, conjointly with the preformed component 3 b and at the mutual spacing thereof, move to the terminal positions thereof and remain there. The preformed component in terms of the height is now positioned within the calibrating swage 22, this being shown in FIG. 8 and in the enlarged manner in FIG. 9.
In order for the completely formed component 3 c to be obtained, the second, outer calibrating die portion 20 a of the calibrating die 20 moves into the preformed component 3 b and progressively widens the latter. The stretching herein ensures that existing corrugations 12 in the side-plate region of the preformed component 3 b are ironed in the circumferential direction and herein are eliminated, and that the site-plate region of the preformed component 3 b assumes the shape of the site-plate region of the completely formed component 3 c. The material for said widening is retrieved by the procedure both from the site-prate region as well as from the base region, the latter on account of the spacing not yet having been finally molded.
The outer edge of the flange region of the preformed component 3 b reaches the vertical wall of the calibrating swage 22 just before reaching the terminal position illustrated in FIG. 10. The widening is thus almost completed. As from this point in time, compressing in which the flange region of the preformed component 3 b is compressed to the final nominal length thereof begins, the length of said preformed component 3 b on account of the preforming and/or the stretching being longer than the associated shoulder on the swage (or the flange region alternatively also having material elevations).
The side-plate region of the preformed component 3 b is simultaneously compressed when said site-plate region has optionally been embodied so as to be somewhat longer than required. The spacing of the calibrating die base 22 b from the calibrating swage base 20 b is also eliminated simultaneously with the calibrating die 20 reaching the terminal position, such that the base region of the now completely formed component 3 c at this point in time is likewise completely molded (FIG. 10).
The material of all regions of the completely formed component 3 c has accordingly been subjected to a final flow procedure in the terminal position. Said material is thus widened, compressed to shape, and by virtue of the plastic flow of all volumetric parts is present in a dimensionally highly accurate manner, having minor or no rebounding.
The calibrating tool 2 is subsequently diverged and the substantially completely formed component 3 c, which requires if at all or only minor peripheral trimming is ejected. Since comparatively large regions have only been widened and not compressed in the method, a lower force requirement moreover results when calibrating than in the case of the methods from the prior art in which substantially all planar regions of the part have to be compressed.
The device and the method here have been explained with reference to a component in the form of a cup having oblique side-plates. However, other component shapes are also possible and require accordingly adapted tool contours.

Claims

1. A method for producing a formed, flanged component, the method comprising the following steps:

preforming a workpiece a preformed component; and

calibrating the preformed component to a substantially completely formed component,

wherein the calibrating of the preformed component to the substantially completely formed component comprises at stretching the preformed component at least in portions.

2. The method as claimed in claim 1, wherein a region of the preformed component is configured so as to have a material deficiency in relation to the completely formed component.

3. The method as claimed in claim 1, wherein a region of the preformed component in terms of a geometric size, is dimensioned so as to be smaller in comparison to the substantially completely formed component.

4. The method as claimed in claim 1, wherein material elevations are permitted while preforming the workpiece to the preformed component.

5. The method as claimed in claim 1, wherein the material elevations are permitted by at least one of providing a gap and a blank-holder spacing in the region of the material elevation.

6. The method as claimed in claim 4, wherein the material elevations are incorporated in a targeted manner by way of at least one preforming tool.

7. The method as claimed in claim 4, wherein the material elevations are substantially free of material thickenings.

8. The method as claimed in claim 4, wherein the material elevations are ironed by stretching the preformed component.

9. The method as claimed in claim 1, wherein a region of the preformed component, in terms of a geometric size, is dimensioned so as to be larger as compared to the substantially completely formed component.

10. The method as claimed in claim 1, wherein the calibrating of the preformed component to the completely formed component comprises compressing the preformed component at least in regions.

11. The method as claimed in claim 1, wherein the preformed component by way of the calibrating is subjected to a plastic flow procedure in one of an entirety of the component and only in portions of the component.

12. A device for producing a formed, flanged component, comprising:

a preforming tool for preforming a workpiece to a preformed component; and

a calibrating tool for calibrating the preformed component to a substantially completely formed component,

wherein the preforming tool and the calibrating tool are configured in such a manner that the calibrating of the preformed component to the substantially completely formed component comprises stretching the preformed component at least in regions.

13. The device as claimed in claim 12, wherein the preforming tool, while preforming the workpiece to the preformed component, is configured for permitting material elevations by use of a gap that remains in at least one of a closed stated and a blank holder spacing of the preforming tool.

14. The device as claimed in claim 13, wherein the preforming tool comprises a preforming die and a preforming swage, and the gap defined at least between the preforming die and the preforming swage.

15. The device as claimed in claim 12, wherein the calibrating tool comprises a calibrating die and a calibrating swage, wherein the calibrating die comprises a first calibrating die portion and a second calibrating die portion which is movable relative to said first calibrating die portion and which forms the calibrating die base.

16. The method as claimed in claim 2, wherein the region is a side-plate region.

17. The method as claimed in claim 3, wherein the region is a side-plate region.

18. The method as claimed in claim 9, wherein the region is one of a side-plate region and a flanged region.

19. The device as claimed in claim 15, wherein the calibrating swage comprises a first calibrating swage portion and a second calibrating swage portion which is movable relative to said first calibrating swage portion and which forms the calibrating swage base.