EP1871553B1 - Method for producing hollow body elements, hollow body element, component, follow-on composite tool for producing hollow body elements and roller mill - Google Patents

Description

The present invention relates to a method according to the preamble of claim 1 for the production of hollow body elements, such as nut elements, for attachment to usually made of sheet metal components, in particular for the production of hollow body elements with an at least substantially square or rectangular outer contour, by cutting individual elements of a in Shape of a profile bar or a roll present profile after prior punching of holes in the profile, optionally with subsequent formation of a threaded cylinder using a progressive tool with multiple workstations in which respective operations are performed. Furthermore, the present invention relates to hollow body elements according to the preamble of claim 22, which are produced by the method, assembly components, which consist of a hollow body member and a sheet metal part and progressive dies for performing the method and rolling mills, which can be used in combination with the progressive tools.

A method of the type mentioned above and corresponding hollow body elements and assembly components are, for example, in the WO-A-2005/09930 (Registration PCT / EP2005 / 003893 of 13 April 2005 ) known. Object of the present invention is to develop the method of the type mentioned so that hollow body elements, in particular rectangular nut elements, can be produced inexpensively, without burdening the tools used so that they early to fail. Furthermore, the hollow body elements produced in this way should have excellent mechanical properties, for example a high pull-out force, excellent resistance to twisting and, moreover, a reduced notch effect, so that the fatigue properties of assembly components consisting of a component usually consisting of sheet metal and hollow body elements attached to it dynamic loads are improved. Furthermore, the hollow body elements should be extremely inexpensive to produce. In addition, a particularly advantageous design of a follow-on composite tool used in the production of the hollow body elements as well as a rolling mill which can be used for the purpose of producing hollow body elements should be provided according to the invention.

The object according to the invention is achieved by a method according to claim 1, by a hollow body element according to claim 22, by an assembly component according to claim 35, by a progressive compound tool according to claim 39 and by a rolling mill according to claim 42, the respective subclaims representing preferred embodiments of the invention.

In the method according to the invention, the profile used thus has a rectangular cross section and is therefore inexpensive to manufacture. The production method according to the invention makes it possible to produce hollow body elements without the tools used being subject to high wear and without the punches failing prematurely. Furthermore, the problem of elongation of the profile strip in the follow-on composite tool has been most effectively overcome in that depending on the design of the incoming profile strip only one forming station or at most two forming stations in the progressive tool are necessary or that according to the invention a station for training an undercut on the pilot part of the hollow body element in comparison to the aforementioned WO-A-2005/099930 (Registration PCT / EP2005 / 003893 ) is no longer necessary.

However, the advantage of the invention is maintained WO-A-2005/099930 ( PCT / EP2005 / 003893 ), according to which the production takes place in working steps, in which for a profile always two processes are carried out in one station. As a result, the productivity of the manufacturing facility is doubled without increasing the cost of manufacturing the progressive compound tool to an extent that would be unjustifiable. Although a doubling of effort is required by the doubling of work elements, but this can easily be amortized relatively early on corresponding production figures.

Although it is possible to process several profiles in parallel in a follow-on composite tool, this is not necessarily preferable, since problems that occur with a profile or with the processing of a profile, the entire follow-on composite tool must be stopped until the disturbance, resulting in significant Production losses could arise. Nonetheless, the present invention could be implemented using a progressive tool that processes multiple profiles simultaneously.

Particularly preferred embodiments of the method according to the invention, the hollow body elements according to the invention, the assembly parts according to the invention as well as the follow-on composite tool according to the invention can be taken from the further claims.

Further advantages of the method according to the invention, the hollow body elements according to the invention as well as the follow-on composite tool used according to the invention can be taken from the figures and the subsequent description of the figures.

Fig. 1

eine Ausführung eines Profils, das in einem Folgeverbundwerkzeug entsprechend der Figur 2 verarbeitet wird, wobei die

Fig. 2

eine in Bewegungsrichtung des Profils geschnittene Darstellung eines Folgeverbundwerkzeugs wiedergibt,

Fig. 3

eine vergrößerte Darstellung des Folgeverbundwerkzeugs der Fig. 2 im Bereich der Arbeitsstationen,

Fig. 4A-4E

eine Darstellung der einzelnen Schritte der Herstellung eines Hohlkörperelements unter Anwendung des Verfahrens und des Folgeverbundwerkzeugs der Fig. 2 und 3,

Fig. 5A-5N

verschiedene Darstellungen des fertig gestellten Hohlkörperelements der Fig. 4A-4E, wobei Fig. 5A eine perspektivische Darstellung des Hohlkörperelements von unten zeigt, Fig. 5B eine Draufsicht auf das Hohlkörperelement von oben, Fig. 5C eine Schnittzeichnung entsprechend der Schnittebene C-C bzw. C'-C' der Fig. 5B und Fig. 5D eine vergrößerte Darstel lung des Bereichs D der Fig. 5C, die weitere Figuren 5E-5I zeigen eine ideale Variante des Hohlkörperelements der Fig. 5A-5D, und zwar ausgelegt für dickere Blechteile, während die Fig. SJ-5N eine weitere ideale Variante zeigen, die zur Anwendung mit dünneren Blechteilen ausgelegt ist,

Fig. 6A-6E

Darstellungen eines weiteren Hohlkörperelements, das eine leichte Abwandlung des Hohlkörperelements gemäß Fig. 5A-5D darstellt, wobei Fig. 6A eine Draufsicht auf das Hohlkörperelement von oben zeigt, Fig. 6B eine Schnittzeichnung entlang der Schnittebene B-B der Fig. 6A, Fig. 6C eine Schnittzeichnung entsprechend der Schnittebene C-C der Fig. 6A wiedergibt und Fig. 6D und 6E perspektivische Darstellungen des Funktionselements von oben und unten sind,

Fig. 7A-7B

die Anbringung des Hohlkörperelements an einem dünnen Blechteil bzw. einem dickeren Blechteil,

Fig. 8A-8D

Darstellungen einer weiteren Ausführungsvariante eines Hohlkörperelements mit Verdrehsicherungsmerkmalen in Form von sich radial erstreckenden Rippen, die die Ringvertiefung überbrücken, wobei die Fig. 8A eine Ansicht auf das Hohlkörperelement von unten, die Fig. 8B und 8C Schnittzeichnungen entsprechend der horizontalen Schnittebene B-B bzw. der senkrechten Schnittebene C-C der Fig. 8A und die Fig.8D eine perspektivische Zeichnung ist bzw. sind,

Fig. 9A-9D

Darstellungen entsprechend den Fig. 8A-8D, jedoch von einer Ausführungsform mit schräg gestellten Verdrehsicherungsrippen, die sich in radialer Richtung über die Ringvertiefung und in axialer Richtung an der Hinterschneidung des Stanzabschnitts entlang erstrecken,

Fig. 10A-10D

Darstellungen entsprechend den Fig. 8A-8D, jedoch von einer Ausführungsform mit abgewinkelten Verdrehsicherungsrippen, die sich in radialer Richtung über die Ringvertiefung und in axialer Richtung an der Hinterschneidung des Stanzabschnitts entlang erstrecken,

Fig. 11A-11D

Darstellungen entsprechend den Fig. 8A-8D, jedoch von einer Ausführungsform mit Verdrehsicherungsmerkmalen, die durch Nuten bzw. Vertiefungen gebildet sind,

Fig. 12A-12D

Darstellungen entsprechend den Fig. 8A-8D, jedoch von einer Ausführungsform mit einer in Draufsicht polygonalen Ringform, im konkreten Fall einer quadratischen Form,

Fig. 13A-13D

Darstellungen eines erfindungsgemäßen Hohlkörperelements, das eine Abwandlung des Hohlkörperelements gemäß Fig. 5A-5D darstellt, wobei die Fig. 13A eine Ansicht von unten auf das freie Stirnende des Hohlkörperelements zeigt, die Fig. 13B eine Schnittzeichnung entsprechend der Schnittebene X111B-X111B der Fig. 13A zeigt, die Fig 13C eine vergrößerte Darstellung des Bereiches X111C der Fig. 13B ist und die Fig. 13D das Hohlkörperelement in einer perspektivischen Darstellung wiedergibt,

Fig. 14A-14D

die Anbringung des erfindungsgemäßen Hohlkörperelements durch einen Nietvorgang an ein vorgelochtes Blechteil,

Fig. 15

einen Längsschnitt durch ein erfindungsgemäßes Folgeverbundwerkzeug, das ähnlich dem Folgeverbundwerk zeug der Fig. 3 ist,

Fig. 16

eine vergrößerte Darstellung des mittleren Bereichs des Folgeverbundwerkzeugs der Fig. 15,

Fig. 17

einen Längsschnitt durch ein weiteres erfindungsgemäßes Folgeverbundwerkzeug, das ähnlich dem Folgeverbundwerkzeug der Fig. 15 ist,

Fig. 18

eine vergrößerte Darstellung des mittleren Bereichs des Folgeverbundwerkzeugs der Fig. 17,

Fig. 19A-19C

eine schematische Darstellung eines ersten erfindungsgemäßen Walzwerks,

Fig. 20A-20C

eine schematische Darstellung eines zweiten erfindungsgemäßen Walzwerks,

Fig. 21A-21C

eine schematische Darstellung eines dritten erfindungsgemäßen Walzwerks;

Fig. 22A-22D

Darstellungen eines weiteren erfindungsgemäßen Hohlkörperelements, wobei die Fig. 22A eine Ansicht von unten, die Fig. 22B eine Schnittzeichnung entsprechend der Schnittebene XXIIB-XXIIB der Fig. 22A, die Fig. 22C eine Schnittzeichnung entsprechend der Schnittebene XXIIC-XXIIC der Fig. 22A und die Fig. 22D eine perspektivische Ansicht darstellt,

Fig. 23A-23D

Ansichten zur Erläuterung der Anbringung des Elements der Fig. 22A-22D an ein relativ dünnes Blechteil (Fig. 23A),

Fig. 24A-24D

Ansichten entsprechend den Fig. 23A-23D, jedoch zur Erläuterung der Anbringung des Elements an ein relativ dickes Blechteil (Fig. 24A),

Fig. 25A-25F

eine Zeichnungsreihe zur Erläuterung der Herstellung des erfindungsgemäßen Elements gemäß Fig. 22A-22D,

Fig. 26

eine in Längsrichtung des Profilstreifens geschnittene Seitenansicht eines Folgeverbundwerkzeugs zur Herstellung des Elements gemäß Fig. 22A-22D und

Fig. 27

eine vergrößerte Darstellung des mittleren Bereichs des Folgeverbundwerkzeugs der Fig. 26.

The figures show in the Fig. 1 to 12 the same figures in the WO -A-2005/099930 ( PCT / EP2005 / 003893 ), which are useful for an understanding of the present invention based on the present invention, as well as FIGS. 13 to 27 which explain the present invention in more detail. Specifically show:

Fig. 1

an embodiment of a profile that in a progressive tool according to the FIG. 2 is processed, the

Fig. 2

a representation of a follow-on composite tool cut in the direction of movement of the profile,

Fig. 3

an enlarged view of the progressive tool of the Fig. 2 in the field of workstations,

Fig. 4A-4E

a representation of the individual steps of the production of a hollow body element using the method and the progressive tool of the Fig. 2 and 3 .

Fig. 5A-5N

various representations of the finished hollow body element of Fig. 4A-4E , in which Fig. 5A shows a perspective view of the hollow body element from below, Fig. 5B a top view of the hollow body element from above, Fig. 5C a sectional view corresponding to the sectional plane CC or C'-C 'the FIGS. 5B and 5D an enlarged representation of area D of the Fig. 5C , the more Figures 5E-5I show an ideal variant of the hollow body element of Figs. 5A-5D and designed for thicker sheet metal parts, while Figs SJ-5N show another ideal variant, which is designed for use with thinner sheet metal parts,

Figs. 6A-6E

Representations of another hollow body element, the a slight modification of the hollow body element according to Figs. 5A-5D represents, where Fig. 6A shows a plan view of the hollow body element from above, Fig. 6B a sectional view along the section plane BB of Fig. 6A, Fig. 6C a sectional view corresponding to the sectional plane CC of Fig. 6A reproduces and FIGS. 6D and 6E are perspective views of the functional element from above and below,

Figs. 7A-7B

the attachment of the hollow body element to a thin sheet metal part or a thicker sheet metal part,

8A-8D

Representations of a further embodiment variant of a hollow body element with anti-rotation features in the form of radially extending ribs which bridge the annular recess, wherein the Fig. 8A a view of the hollow body element from below, the Figs. 8B and 8C Sectional drawings corresponding to the horizontal section plane BB or the vertical section plane CC of the Fig. 8A and the Figure 8D is a perspective drawing,

Figs. 9A-9D

Representations according to the 8A-8D However, of an embodiment with inclined anti-rotation ribs, extending in the radial direction over the annular recess and extend in the axial direction along the undercut of the punching section,

10A-10D

Representations according to the 8A-8D but of an embodiment with angled anti-rotation ribs extending in the radial direction over the annular recess and in the axial direction along the undercut of the punching section,

Figs. 11A-11D

Representations according to the 8A-8D but of an embodiment with anti-rotation features formed by grooves,

Figs. 12A-12D

Representations according to the 8A-8D but of an embodiment with a polygonal ring shape in plan view, in the concrete case of a square shape,

Figs. 13A-13D

Representations of a hollow body element according to the invention, which is a modification of the hollow body element according to Figs. 5A-5D represents, wherein the Fig. 13A a bottom view of the free end face of the hollow body member shows, the Fig. 13B a sectional drawing corresponding to the cutting plane X111B-X111B the Fig. 13A show the Fig. 13C an enlarged view of the area X111C the Fig. 13B is and the Fig. 13D shows the hollow body element in a perspective view,

Figs. 14A-14D

the attachment of the hollow body element according to the invention by a riveting operation to a pre-punched sheet metal part,

Fig. 15

a longitudinal section through an inventive composite progressive tool, the zeug similar to the progressive composite Fig. 3 is

Fig. 16

an enlarged view of the central region of the progressive tool of the Fig. 15 .

Fig. 17

a longitudinal section through another inventive progressive compound tool, similar to the progressive die of Fig. 15 is

Fig. 18

an enlarged view of the central region of the progressive tool of the Fig. 17 .

Figs. 19A-19C

a schematic representation of a first rolling mill according to the invention,

Figs. 20A-20C

a schematic representation of a second rolling mill according to the invention,

Figs. 21A-21C

a schematic representation of a third rolling mill according to the invention;

Figs. 22A-22D

Representations of another hollow body element according to the invention, wherein the Fig. 22A a view from below that Fig. 22B a sectional drawing accordingly the cutting plane XXIIB-XXIIB of Fig. 22A , the Fig. 22C a sectional drawing corresponding to the sectional plane XXIIC-XXIIC of Fig. 22A and the Fig. 22D represents a perspective view,

Figs. 23A-23D

Views explaining the attachment of the element of Figs. 22A-22D to a relatively thin sheet metal part ( Fig. 23A )

Figs. 24A-24D

Views according to the Figs. 23A-23D but to explain the attachment of the element to a relatively thick sheet metal part ( Fig. 24A )

Figs. 25A-25F

a series of drawings to explain the preparation of the inventive element according to Figs. 22A-22D .

Fig. 26

a cut in the longitudinal direction of the profile strip side view of a progressive tool for the production of the element according to Figs. 22A-22D and

Fig. 27

an enlarged view of the central region of the progressive tool of the Fig. 26 ,

Fig. 1 shows a portion of an elongated profile 1 with a rectangular cross section, a first broad side 2, a second broad side 3 and two narrow sides 7, 8. The longitudinal edges 9 of the profile can be rounded as shown. But they can also have a different shape, such as a chamfer or a rectangular shape. The profile is machined in a follow-on composite tool to form hollow elements, for example, nut elements of substantially rectangular or square shape, manufacture. If the hollow elements are to be realized as nut elements, a thread must be cut or produced in the hole of the hollow body element. This is usually done outside of the progressive tool in a separate machine. It is also possible to produce the thread only after attachment of the hollow body member to a sheet metal part, for example by means of a thread-forming or thread-cutting screw. Furthermore, it is not necessary to provide a thread in the hollow body element, but the perforation of the hollow body element could serve as a smooth bore for rotatably supporting a shaft or as a plug-in receptacle for receiving a plug pin.

A first progressive composite tool 10, which is used to produce hollow body elements from the profile 21 of the Fig. 1 or a similar profile is in Fig. 2 shown in longitudinal section, wherein the longitudinal section is made through the center of the profile.

You look Fig. 2 a lower plate 12, which is usually attached to a press table, either directly or indirectly over an intermediate plate, not shown. The lower plate 12 carries a plurality of columns 14, four in this example, two of which are apparent, namely the two columns which lie behind the cutting plane. Above the columns is another plate 16 which is usually attached to the upper die plate of the press or to an intermediate plate of the press. On the plate 16 guides 18 are screwed (for example by means of screws, which are not shown here), wherein the guides 18 are designed to slide in accordance with the lifting movement of the press up and down the columns 14. The profile 1 is advanced in the direction of arrow 20 at each stroke of the press, by an amount equal to twice the longitudinal dimension L of the individual hollow body elements produced from the profile is. One notices that in the representation according to Fig. 2 and 3 the profile 1 with the second broad side 3 is directed upward through the progressive tool. As from the enlarged view of the central region of the progressive tool from the Fig. 3 it can be seen, the follow-on composite tool in this example comprises four workstations A, B, C, D, in which two treatments are made simultaneously at each stroke of the press.

In the first station A, a so-called enforcing procedure is carried out as the first step a).

In the second workstation B, a punching operation is carried out in a second step b) and a squeezing operation is carried out in the third workstation C in a third step c). Finally, in the fourth workstation D, a knock-down punch 22 is used to separate two hollow-body elements from the profile 1 at each stroke of the press. In this case, the right side of the punch cuts through the profile at a separation point, which is behind the first hollow body element, ie the hollow body element 21 in Fig. 3 located as well as at a separation point behind the second hollow body element 21 '. The progressive tool is in the Fig. 2 and 3 shown in the closed position, in which the two hollow body elements 21 and 21 'have just been separated from the profile 1. Shortly before the knocking off the front side of the nut member 21 contacts the inclined surface 24 of the rectangular cam 27, which is pressed by a helical compression spring 26 down. The advance of the profile strip therefore presses over the inclined surface of the cam 24 upwards, whereby the spring 26 is compressed. After the separation of the first hollow body member 21, the cam 24 presses on the right side of the nut member 21 and tilts this in the inclined position, on the right side of the Fig. 3 is apparent. The nut member 21 drops then on a chute from the work area of the progressive tool and can, for example, in the position according to Fig. 2 then be led out laterally from the progressive compound tool, for example via its side chute under the action of gravity or with a blast of compressed air, etc.

The second hollow body member 21 'passes through a hole 28 in the tee die 30 and then through corresponding bores 32, 34, 36 and 38 formed in plates 40, 42, 44 and 12.

The bores or the hole 38 in the plate 12 can be aligned with a further bore (not shown) in the press table or in any intermediate plate provided between the plate 12 and the press table, which allows the removal of the nut elements such as 21 ', for example under the By gravity or by a lateral chute or by applying a blast of compressed air.

At the concrete, in Fig. 3 shown construction, the plate 44 is bolted to the plate 12 via screws, not shown. The plate 42 consists of a plurality of plate sections, which are assigned to the respective work stations, which are screwed to the continuous plate 44 via further, not shown screws (since arranged outside the plane of the sectional view). The continuous plate 40 is also bolted to the sections of the plate 42, again by means not shown screws. Above the continuous plate 40 are again plate sections 50, 52, 54, 56, 58 and 60, which in turn are bolted to the plate 40. The plate 50 is a support plate, which forms a lower guide for the profile 1, more precisely for the first broad side 2 of the profile 1, which in this illustration the underside forms. The plate sections 52, 54 and 56 are associated with the work stations A, B and C, while the plate sections 58 and 60, which form a receptacle for the tee die 30, are associated with the workstation D.

In several places between the continuous plate 44 and the plate sections 50, 52, 54, 56, 58 and 60 are strong helical compression springs 62, of which only one spring in the Fig. 2 and 3 can be seen, since the others are arranged outside the cutting plane. These springs, such as 62, have the function of lifting the plate sections 50 to 60 when the press is opened, as a result of which also the profile strip 1 is lifted and thereby passes out of the working area of the puncturing punches 64, 66, whereby the profile is reduced by twice the length L the hollow body elements 21 can be further advanced.

The parting plane of the progressive tool is located above the profile 1 and is T in Fig. 3 designated.

Above the profile strip are in turn plate sections 72, 74, 76, 78 and 80, which are bolted to a continuous plate 82 - again on screws, not shown. Further, the plate 82 is bolted to the upper plate 16.

Upon opening of the press, the plates 72, 74, 76, 78 and 80 are thus lifted with the plate 22 and the upper plate 16, so far that the two punch 84, 86 and the two upper Abflachstempel 88 and 90, such as also the dies 92 and 94 which cooperate with the puncturing punches 64, 66 and also the tee punches 22 out of engagement with the profile strip 1 arrive. By this movement, coupled with the raising of the profile strip by the spring 62, it is possible that the profile strip 1 can be pushed further by twice the length dimension of the hollow body elements 21 in preparation for the next stroke of the press.

It can be seen that workstations A and B have a length dimension, i. in the direction of movement 20 of the profile strip 1, which corresponds to four times the length dimension of a hollow body element 21. The work station C has a length dimension which corresponds to three times the length dimension of a hollow body element 21, while the work station D has a length dimension which has a multiple of the length dimension of the hollow body element 21, in this example six times. This means that so-called empty places such as 98 are present, at which no processing of the profile strip 1 takes place. However, these empty spaces create space that is necessary to make the individual components of the tools used sufficiently stable and support.

Furthermore, you look Fig. 3 in that the perforation dies 100, 102, which cooperate with the punches 84, 86, have a central bore 104, 106, respectively, which are aligned with further bores 108, 110 in insert sleeves 112, 114, which make it possible to produce the punches 116, 118 to dispose of. These fall through the bore 108, 114, which are larger in diameter than the bore 104, 106 and through the further holes 120, 122 in the plate 12 downwards and can pass through corresponding passages in the press table or in any intermediate plate provided in the same way as the parent elements 21 'disposed of or discharged.

Although not shown, are located to the left and right of the profile strip 1, ie behind the plane of the drawing and in front of the plane of the drawing of the Fig. 3 , Guiding elements, which may be formed, for example by cheeks of the plates 50, 52, 54, 56 and 58, which ensure that the profile strip follows the desired trajectory through the progressive tool. It may be provided a slight lateral clearance, which allows a possible expansion of the profile strip in the transverse direction.

The constructive details of the puncturing punches 64, 66, the dies 92, 94 cooperating therewith, the punches 84, 86 of the dies 100, 102 cooperating therewith and the flattening punches 88, 90 are shown in the drawings of FIGS Fig. 2 and 3 and are otherwise explained in more detail in the following drawings.

By means of the progressive dies of the Fig. 2 . 3 For example, a method for producing hollow body elements, such as nut elements, for attachment to usually made of sheet metal components is realized. The method is used to produce hollow body elements 21, 21 ', for example with an at least substantially square or rectangular outer contour, by cutting individual elements from a present in the form of a profile bar or a roll profile 1 after prior punching holes 23 in the profile 1, optionally with subsequent formation of a threaded cylinder using a progressive tool with multiple workstations A, B, C, D, in which respective processing is performed. The method is characterized in that in each workstation A, B, C, D for the profile 1 or for a plurality of juxtaposed profiles in each case two machining operations for each stroke of the progressive tool are performed simultaneously. That is, it is basically possible to process several profiles 1 side by side and at the same time in the same progressive tool, provided that the corresponding number of individual tools, such as puncture punches, punches and associated matrices, is present.

In the last workstation, two hollow body elements 21, 21 'are separated by means of a tee-off punch 22 from or from each profile 1.

The knock-off punch 22 cuts through the profile at a first location behind a first hollow body element 21 and at a second location behind a second hollow body element 21 ', wherein the second hollow body element 21' in the direction of the movement of the tee punch transversely to the longitudinal direction of the profile 1 from the movement path of the profile is led out. The first hollow body element 21 is led out in the teetering station of the progressive tool at least for the time being generally in the direction of the movement path of the profile.

Each workstation of the follow-on composite tool has a length in the direction of travel of the profile which corresponds to three times or four times or several times the longitudinal dimension of a finished hollow body element 21, 21 '.

In the illustrated embodiment of the progressive tool, a spring-loaded cam 27 is biased against the force of a spring means 26 with a cam surface 24 inclined to the trajectory of the profile from the leading edge of the leading end of the profile at the exit end of the last work station. After separation of the formed at the front end of the profile hollow body member 21, this is tilted by the spring-loaded cam down to facilitate removal from the progressive tool.

In the execution according to Fig. 2 and 3 For example, the lower punches 64, 66 for performing the puncturing operation and the punches 84, 86 for perforating from opposite sides of the tread 1 operate thereon. When performing the flattening process, respective flattening dies 88, 90 are acted upon from above onto the profile strip 1, while the strip is supported in the area of the perforation by a plate section 56. Instead, it would also be possible to arrange support pins on the plate portion 56 at the locations of the holes in the profile strip, if necessary, to support the profile material in this area during the flattening process, for example, to achieve a sharp-edged formation of the end face of the hollow punching section.

Some examples will now be given describing the production of certain hollow body elements.

1. a) In einem ersten Schritt, ausgehend von einem im Querschnitt rechteckigem Profil 1, Fig. 4A), wird ein Durchsetzvorgang unter Anwendung der Durchsetzmatrizen 92, 94, die von oben kommen, und der Durchsetzstempel 64, 66 durchgeführt. Der Durchsetzvorgang führt zu einer zylindrischen Vertiefung 208 an einer ersten Breitseite 2 des Profils 1 und einem hohlzylindrischen Vorsprung 210 an einer zweiten, der ersten Breitseite 2 gegenüber liegenden Breitseite 3 des Profils, der von einer ringförmigen Vertiefung 212 umgeben ist, die in Fig. 4B gezeigt ist. Der Profilstreifen 1 wird beim Schließen der Presse bzw. des Folgeverbundwerkzeugs auf die oberhalb des Plattenabschnitts 52 hervorstehenden Enden der Durchsetzstempel 64 und 66 gedrückt. Die hervorstehenden Enden der Durchsetzstempel haben eine zu der Form der zylindrischen Vertiefung 208, die in Fig. 4B gezeigt ist komplementäre Form. In ähnlicher Weise haben die Stirnenden der mit dem Durchsetzstempel zusammen arbeitenden Matrizen 92, 94 eine zu der des hohlzylindrischen Vorsprungs 210 und der diese umgebenden Ringvertiefung 212 gemäß Fig. 4B komplementäre Form.
2. b) In einem zweiten Schritt wird ein zwischen dem Boden 214 der zylindrischen Vertiefung 208 und dem Boden 216 des hohlzylindrischen Vorsprungs 210 verbleibender Steg 218 beim Schließen der Presse bzw. des Folgeverbundwerkzeugs 10 mittels der Lochstempel 88, 90 zur Ausbildung des durchgehenden Loches 204 (Fig. 4C) durchlocht. Die Stanzbutzen werden wie erwähnt über die Bohrungen 104, 106 bzw. 108, 110 entsorgt.
3. c) In einem dritten Schritt wird der hohlzylindrische Vorsprung 210 an seinem freien Stirnende 220 zur Ausbildung eines auf der Außenseite hinterschnittenen Stanzabschnitts 222 abgeflacht, wodurch die Stirnfläche 224 in Fig. 4D ausgebildet wird, die in einer Ebene parallel zu den Breitseiten 2 und 3 und senkrecht zur mittleren Längsachse 226 des Lochs 204 steht. Danach können die Hohlkörperelemente in der Arbeitsstation D vom Profil abgetrennt und anschließend gegebenenfalls mit Gewinde 206 versehen werden, wie in Fig. 4E bzw. in der dazu identischen Fig. 5C gezeigt.

Referring to the Fig. 4A - 4E and the Fig. 5A -5D Now, the method described so far for the production of hollow body elements, such as nut elements, described, which are designed for attachment to usually consisting of sheet metal components. In particular, this relates to a method for producing hollow body elements 200 with an at least substantially square or rectangular outer contour 202 by cutting individual elements from one in the form of a profile bar (1, FIG. Fig. 1 ) or a roll of present profile after prior punching of holes 204 in the profile, optionally with subsequent formation of a threaded cylinder 206 using a progressive tool ( Fig. 2 . Fig. 3 ) having a plurality of workstations A, B, C and D in which respective processes are performed. The procedure is characterized by the following steps:

1. a) in a first step, starting from a profile 1 which is rectangular in cross-section, Fig. 4A ), a piercing operation is performed using the piercing dies 92, 94 coming from above and the piercing dies 64, 66. The passage leads to a cylindrical recess 208 at a first broad side 2 of the profile 1 and a hollow cylindrical projection 210 at a second, the first broad side 2 opposite broad side 3 of the profile, which is surrounded by an annular recess 212 which in Fig. 4B is shown. The profile strip 1 is pressed when closing the press or the progressive tool on the protruding above the plate portion 52 ends of the puncturing punches 64 and 66. The protruding ends of the puncturing punches have a shape similar to that of the cylindrical recess 208 shown in FIG Fig. 4B shown is complementary shape. Similarly, the front ends of the dies 92, 94 cooperating with the punching punch have a ring groove 212 corresponding to that of the hollow cylindrical projection 210 and the annular recess 212 surrounding it Fig. 4B complementary form.
2. b) In a second step, a web 218 remaining between the bottom 214 of the cylindrical recess 208 and the bottom 216 of the hollow cylindrical projection 210 when the press or follow-on composite tool 10 is closed by means of the punches 88, 90 to form the through hole 204 (FIG. Fig. 4C ). The punched slugs are disposed of as mentioned above the holes 104, 106 and 108, 110.
3. c) In a third step, the hollow cylindrical projection 210 is flattened at its free front end 220 to form an undercut on the outside punching portion 222, whereby the end face 224 in Fig. 4D is formed, which is in a plane parallel to the broad sides 2 and 3 and perpendicular to the central longitudinal axis 226 of the hole 204. Thereafter, the hollow body elements can be separated in the workstation D from the profile and then optionally provided with thread 206, as in Fig. 4E or in the identical Fig. 5C shown.

The third step could optionally be combined with step b).

During the passage of step a), the diameter of the cylindrical recess and the inner diameter of the hollow cylindrical projection are at least substantially equal.

Furthermore, the mouth 229 of the cylindrical recess 208 is preferably carried out at the first broad side 2 of the profile with a rounded or chamfered inlet edge 230 during the insertion process of step a) or during the punching process of step b) or the flattening process of step c) Elements forms the thread outlet.

When passing through the step a) or the hole process of step b) or the flattening of step c) is preferably also the mouth 232 of the hollow cylindrical projection 210 at its free end with a rounded or chamfered outlet edge 234 provided in the completed element the thread inlet forms.

When piercing the web according to step b), the hole 204 is produced with a diameter which at least substantially corresponds to the diameter of the cylindrical recess 208 and the inner diameter of the hollow cylindrical projection 210. Further, at The first step is performed by a) providing the free end of the hollow cylindrical projection 210 with a chamfer 236 on the outside. In addition, the annular recess 212 is provided in this enforcing operation with an annular bottom portion 238 which is at least approximately in a plane parallel to the first and second broad side 2, 3 of the profile strip, on the radially inner side with an at least substantially rounded transition 240 in the outside of the hollow cylindrical projection 210 and on the radially outer side merges into a conical surface 242 having an included cone angle in the range between 60 to 120 °, preferably at about 90 °.

The transition 243 from the annular portion 238 of the annular recess 212 in the conical surface 242 is rounded, as well as the outlet 245 of the conical surface of the annular recess 212 in the second broad side 3 of the profile. The cone surface 242 may in practice be such that the rounded transition 243 merges tangentially into the rounded outlet 245.

When the undercut 244 is produced, it is formed by a cylindrical part of the hollow cylindrical projection 210 which merges approximately at the height of the second broad side 3 of the profile 1 into a region 246 of the hollow cylindrical projection 210 that is thickened when step c) is carried out Essentially projecting beyond the second broad side 3 of the profile.

The thickened portion 246 of the hollow cylindrical projection 210 is at least substantially cone-shaped and diverges away from the first and second broad sides, wherein the cone angle of the thickened portion of the hollow cylindrical projection adjacent to the end face 224 in the range between 30 ° and 70 °, preferably at about 50 ° is. After the flattening process, the hollow cylindrical projection 219 terminates at its free end on the outside in a preferably sharp-edged punching edge 250.

As in particular from the Figs. 5A and 5B can be seen, the annular recess is designed with an outer diameter which is only slightly smaller than the smallest transverse dimension of the rectangular in plan view hollow body element, whereby the annular recess 212 with the second broad side 3 of the profile 1 at the narrowest points in the plane of the second broadside 3 remaining webs 284, 286 in the range of 0.25 to 1 mm, preferably of about 0.5 mm.

The Fig. 5E-5I and Figs. 5J-5N show substantially the same elements as Figs Figures 5A-5D , but with small deviations with respect to the formation of the punching section 222, which in the two versions according to Fig. 5E-5I or 5J-5N has an ideal shape.

In the Fig. 5E-5I or 5J-5N, the same reference numerals have been used, which were also used in connection with the previous embodiments. It is understood that the previous description also for the Fig. 5E-5I or 5J-5N, ie that the earlier description of features with the same reference numerals or for the description of the Fig. 5E-5I or 5J-5N applies. This convention is retained in the other figures, so that only essential differences or significant features are described here extra.

The main difference between the execution according to Fig. 5E-5I and the execution according to Figs. 5J-5N is that the execution according to Fig. 5E-5I is used for thicker sheets in the range of, for example, 1.2 to 2.0 mm sheet thickness, while the execution according to Figs. 5J-5N For rather thinner sheets, for example in the range of 0.4 to 1.2 mm sheet thickness is used.

Specifically, the shows Fig. 5E a view from below of the lower end face of the punching section 222, ie in the direction of arrow E of Fig. 5H , The Fig. 5F is a sectional drawing corresponding to the vertical sectional plane FF in Fig. 5E , so in Fig. 5F the two anti-rotation ribs 272 extending in the axial direction and located at the 12 o'clock and 6 o'clock position in Fig. 5E can each be seen in section. In contrast, the four other anti-rotation ribs 272 ', which in Fig. 5E are registered, neither in Fig. 5F still in Fig. 5G , which shows a sectional drawing corresponding to the cutting plane GG, can be seen. You can also only hint in Fig. 5E be recognized, since they are hidden in principle behind the punching section 222 as far as possible. In the sectional drawing of Fig. 5G they are not visible because the cutting plane is selected so that the anti-rotation ribs 272 and 272 'are not in the cutting plane or adjacent to the cutting plane and are not so large that they could be recognized in side view in the cutting plane.

The Figs. 5H and 5I each show an enlarged view of the in a dash-dotted rectangle in Fig. 5G or 5F shown areas. From the Fig. 5H to 5I It can be seen that the lower end face 224 of the punching section 222 is illustrated in the sectional plane by a radius which terminates tangentially at the cutting edge 250.

This makes a difference to the end face 224 of the embodiment according to Figs. 5A-5D which has a clear annular surface portion in a plane perpendicular to the central longitudinal axis 226 of the hollow body element.

Furthermore, in particular from the drawings according to Figs. 5H and 5I to recognize that the cone-shaped inclined surface 242 in Fig. 5D per se designated area of the annular recess 212 is formed by two radii, which merge into one another at a turning point, in this example with only a very short straight line, which is indicated by the two lines 301 and 303, and which are also not present in practice must, ie the two radii, which form the inclined wall of the recess (curved portions 243 and 245) can merge directly tangentially into each other. Nevertheless, in the area of the inflection point there is an area which can be described as approximately flat, so that the term "at least substantially cone-shaped" is justified. Of course, a clear, strictly cone-shaped area could also be provided.

By using the same reference numerals, it can be seen that the Figures 5J-5N are to be understood as well as the Figures 5E-5I , The only difference here is that the anti-rotation lugs 272 'in Fig. 5E in Fig. 5J can not be seen, and that is not because they are really hidden behind the annular cutting edge 250. Thus, the anti-rotation lugs 272 are only in Fig. 5K or in Fig. 5N to see.

In an alternative method, to the hollow body element according to the FIGS. 6A to 6E leads, the enforcement process according to step a) through the application of correspondingly shaped through-punches 64, 66 and clinching 92, 94 on the first broad side 2 of the profile around the cylindrical recess 208 around an annular elevation 260 formed, for example, at least substantially represents a volume of material , the volume of the annular recess 212 around the hollow cylindrical Lead around equals. In this embodiment, the diameter of the cylindrical recess 208 is greater than the inner diameter of the hollow cylindrical projection 210. Further, the thread 206 ends in a conical region 262 of a stepped hole 264, which may optionally be used in this example instead of a rounded thread spout (which also in the Execution according to FIGS. 4A to 4C respectively. Figs. 5A to 5D it is possible).

The bottom of the annular recess is formed in this embodiment alone by a rounded transition 243 from the hollow cylindrical projection 210 in the conical surface 242, which also in the embodiment according to Fig. 4A to 4E respectively. Figs. 5A to 5D it is possible.

During the penetration process according to step a), as in Fig. 5A and Fig. 6E can be seen formed by appropriate profiling of the piercing dies 92, 94, anti-rotation features 272 on the outside of the hollow cylindrical projection 210 and inside the annular recess 212 around the hollow cylindrical projection 210 around.

These anti-rotation features may be formed by ribs 272 and / or grooves (not shown) on the radially outer side of the hollow cylindrical projection 210 (as shown). These ribs 272 extend in the axial direction 226 and bridge the undercut 244 of the hollow cylindrical projection 210. They have a radial width which corresponds at least substantially to between 40% and 90% of the maximum radial depth of the undercut.

This results in a hollow body element 200 for attachment to a usually made of sheet metal component 280 (FIG. Fig. 7A respectively. Fig. 7B ) having an at least substantially square or rectangular Outer outline 202, with a first broad side 2 and a second broad side 3, with an undercut 244 having punching portion 246 which projects beyond the second broad side and is surrounded by an annular recess 212 in the second broadside and with a hole 204 extending from the first broad side 2 extends through the punching section 246, wherein the hole optionally has a threaded cylinder 206 and the hollow body element is characterized in that anti-rotation features 272 outside of the hollow cylindrical projection 210 and / or inside in the region of the annular recess 212 are formed around the hollow cylindrical projection 210 around ,

The hollow body element is further characterized in that the second broad side 3 is located radially outside the annular recess 212 in a plane, i. Apart from any curves or bevels at the transitions in the side edges of the hollow body member, and thus has no beams, grooves or undercuts in the area outside the annular recess.

The annular recess 212 is designed with an outer diameter which is only slightly smaller than the smallest transverse dimension of the rectangular in plan view hollow body element, whereby the annular recess with the second broad side 3 of the profile at the narrowest points 284, 286 in the plane of the second broadside remaining webs in Range from 0.25 to 1 mm, preferably from about 0.5 mm.

The Figs. 7A and 7B show as one and the same inventive element 200 according to Figs. 5A to 5D with a thinner sheet metal part ( Fig. 7A ), for example, 0.7 mm thick and with a thicker sheet metal part ( Fig. 7B ) of, for example, 1.85 mm thickness can be used. The sheet material fills after compression by means of a die the entire Ring recess 212 and lies against the full surface of the annular recess and the anti-rotation features 272 in the region of the undercut. In both cases, therefore, a good coverage with the anti-rotation ribs 272 and therefore a good rotation between the hollow body member 200 and the sheet metal part 280. The punching section 246, which is at least substantially not deformed in these examples, is self-piercing introduced into the sheet metal part. The flattened end face 224 of the punching section 246 is located at thin sheets (as in Fig. 7A shown) in the height of the underside of the sheet metal part and in thicker sheet metal parts ( Fig. 7B ) above the underside of the sheet metal part (ie, the side of the sheet metal part facing away from the body part of the hollow body element). In both cases, there is an annular recess 282 around the punching section, which is predetermined in its shape by the concrete shape of the complementarily shaped die in the self-piercing attachment of the hollow body element in a press or by a robot or in a C-frame. In this case, the die, as usual in the self-piercing attachment of fasteners, a central bore, through which the resulting punching is disposed of. Although the hollow body elements according to the invention are self-piercing, they can still be used in pre-punched sheet metal parts. With a second embodiment of the hollow body element according to the invention, a further thickness range of sheet metal parts, for example 1.85 to 3 mm, can be covered. Only the punching section needs to be made longer.

Since the square-shaped in hollow body elements are mounted so that the second broad side 3 is applied directly to the top of the sheet metal part 280, but not or substantially not dig into the sheet metal part, a notch effect is not to be feared, so that a good fatigue thanks good fatigue resistance too dynamic loads. Although the hollow body elements are square in plan view, no special orientation of the die is required per se with respect to the particular setting head used because the punching section in plan view is circular and therefore orientation-free. It only needs to be ensured that the setting head and the die are coaxial with each other and to the longitudinal axis 226 of the hollow body element. When attaching another component to an assembly component according to Fig. 7A or 7B the further component is usually below the sheet metal part by a screw (not shown) attached, which is screwed coming from below into the thread. As a result, the connection between the hollow body element 200 and the sheet metal part is reinforced by tightening the screw.

Furthermore, it should be pointed out that anti-rotation ribs would be conceivable which traverse the annular recess 212 in the radial direction or bridge it, for example in the FIGS 8A-8D . Figs. 9A-9D or 10A-10D shown. Such anti-rotation ribs can be flush with the broad side 3 ( 8A-8D ) or recessed within the annular recess (such anti-rotation features are not shown in the drawings).

In the embodiment according to 8A-8D are the free upper sides of the anti-rotation ribs, which are indicated by 272 ", in the same plane as the surface of the broad side 3 outside the annular recess 212. The sides 272" can also be arranged offset from the broad side 3 back. Since the anti-rotation ribs bridge over the annular recess 212, they can also be found on the side of the annular punching section 222 in the region of the undercut 244.

The Figs. 9A-9C show a further variant in which the anti-rotation features in the form of anti-rotation ribs extending in the radial direction over annular recess 212, only the tops 272 "'of the anti-rotation ribs 272 of the embodiment according to Figs. 9A-9D inclined so that they rise in the direction of the punching section 222 rising and therefore not only extend in the radial direction over the annular recess and bridge it, but also in the axial direction of the undercut 244 of the punching section 222 over a considerable length or in the full length of the undercut 244 extend.

The 10A-10D show an embodiment that of the Figs. 9A-9D is very similar, except that here are the anti-rotation ribs angled so that they have a radial portion 272 "" and an axial portion 272 ""', which are interconnected over a radius 272 """and therefore have a total of the discussed angled shape.

The Figs. 11A-11D show another type of anti-rotation features, here in the form of recesses 272 '''' or grooves formed in the inclined side wall of the annular recess 212, wherein the recesses 272 '''' here in plan view have an approximately cup-like shape. Other shapes of the depressions are conceivable, for example elongated grooves, which are narrower in the region of the broad side 3.

Finally, the show Figs. 12A-12D a slightly different shape of a hollow body element.

The essential difference in the shape of the hollow body member of the embodiment according to Figs. 12A-12D is to be seen in that the ring recess Here, a polygonal shape 212 ', in the specific case a square shape in plan view, wherein the annular recess has a corresponding number, ie four, inclined surfaces 400, 402, 404 and 406, by means of radii 408, 410, 412 and 414 merge into each other. At the lowest point of the annular recess 212 ', which is polygonal in plan view, there is a surface region which is defined by four corner regions 416, 418, 420 and 422 and is arranged in a plane perpendicular to the central longitudinal axis 226 of the element. Punching section 222 transitions over a radius 424 into these corner regions, the radius at the radially outermost point having a diameter which is slightly larger than the maximum transverse dimension of the surface region formed by the four corners 416, 418, 420 and 422 that this radius eventually merges into the bottom of the four sloping surfaces. All thin parallel lines such as 426, 426 'and 426 "show radii or rounded surfaces which provide, inter alia, for a gentle bending of the sheet metal part.

In this embodiment, it is not necessary to provide separate anti-rotation ribs, since the polygonal shape of the annular recess 212 'itself provides the required anti-rotation. This embodiment is also advantageous because the inclined surfaces and the corner regions in the bottom region of the annular recess belong to the contact surface of the element, so that can be used with correspondingly low surface pressures on the sheet metal part and the risk of Nachsitzens the element is not given. Nevertheless, high anti-rotation values can be achieved, as well as a high pull-out resistance.

The rounded areas between the inclined surfaces also have the advantage that there are no pronounced sharp features at these locations in the sheet metal part, which can lead to fatigue, in particular with dynamic loading of the component. Since the punching section 222, as in the other embodiments, generates a circular hole in the sheet metal part, no stress concentrations are to be expected here, which can lead to fatigue cracks during operation. When attaching the hollow body member to a sheet metal part, the element is at least substantially not deformed, deformation is undesirable, and the sheet metal part is formed by a suitable complementary shape of the die in the square recess 212 'in the area around the punching portion 222 and completely in Plant brought with this punching section around the punching section around.

In all embodiments of the 8A-8D to Figs. 12A-12D the hollow body element is formed flat on the first broad side 2, ie with an end face which is perpendicular to the central longitudinal axis 226 of the element, according to the previous embodiment of the Fig. 5A-5N , But it is quite conceivable that the corresponding end face in the embodiments according to 8A-8D to Figs. 12A-12D similar to the embodiment according to Fig. 6D could be trained. Both Figs. 12A-12D This means that instead of a circular survey as in Fig. 6D shown, the survey will then have a corresponding polygonal shape, here a square shape.

In this application, when talking about a polygonal shape, this definitely includes polygons having three to twelve polygonal faces, i. inclined surfaces.

In the embodiment according to Figs. 12A-12D As shown, a significant material displacement takes place in the region of the square recess in plan view, so that it is quite possible here, the hollow cylindrical projection, which converts by flattening in the punching section 222 is achieved solely by material displacement from the second broad side 3 of the hollow body element, ie it is not necessary to perform in the first step of the manufacturing process, a penetration method in which material is displaced from the first broad side 2 from. That is, the first manufacturing step a) according to claim 1 can be replaced here by a molding process in which the hollow cylindrical projection 210 is effected solely by material displacement from the region of the polygonal ring recess in plan view and in the region of the hollow cylindrical projection 210. During the subsequent piercing process, the body thus formed is then pierced through from the first broad side 2 to the bottom 216 of the cavity 232.

The formation of the annular recess 212 need not necessarily be simultaneous with the piercing operation, but could be combined with the piercing or flattening process, i. the punches 84, 86 and the flattening dies 88, 90 would have to have a corresponding shape in this case.

It is not necessary to separate the hollow body elements in the progressive tool from each other, but the profile can be maintained or used after production of the general shape of the hollow body elements in sections or in rewound form, with a separation into individual hollow body elements takes place only when the profile in a setting head for attachment of the hollow body elements is used on a component.

The methods according to the invention, hollow body elements, assembly components, follow-on composite tools and rolling mills will now be described, which by a modification or a simplification of the hitherto in connection with the Fig. 1 to 12 described method, hollow body elements, Assembly components, and follow-on composite tools arise. To the description of the invention according to FIGS. 13 to 27 to facilitate the same reference numerals are used, which also in connection with the embodiments of FIG Fig. 1 to 12 were used. It is understood that the previous description also for the FIGS. 13 to 27 applies, ie that the earlier description of features with the same reference numerals for the description of FIGS. 13 to 27 applies, so that it is only necessary to describe the main differences. Therefore, only essential differences or significant features will be described separately here.

Referring to the Figs. 13A to 13D there is shown a hollow body element, the element according to Figs. 5A to 5D corresponds, except for the fact that the pilot part, ie the hollow projection 210, is executed here without undercut. Consequently, the axial anti-rotation ribs 272 can be seen better because they are not hidden in an undercut, but protrude in the radial direction of the hollow cylindrical projection 210 here. Furthermore, it can be seen that the thread in the hollow body elements according to the invention immediately before the hollow cylindrical projection comes to an end, that does not extend into the hollow cylindrical projection, otherwise it would be deformed during the forming of the hollow cylindrical projection or rivet section 210, which is the introduction of a Make screw difficult or impossible.

Although the hollow body element according to the invention only in connection with a modification of the embodiment according to the Figs. 5A to 5D has been described, all previously described embodiments of hollow body elements, ie, inter alia, the hollow body elements of Fig. 5E to 5N , of the FIGS. 6A to 6E , of the 8A to 8D , of the Figs. 9A to 9D , of the 10A to 10D , of the Figs. 11A to 11D and the FIGS. 12A to 12D be made into hollow body elements according to the invention, in that the undercut of the hollow projection 210 is omitted, so that a cylindrical projection is formed, as shown in Figs. 113A to 13D shown, however, with the embodiments of the respective anti-rotation characteristics of said figures.

This raises the question of how such hollow body elements according to the invention can then be applied to the sheet-metal part in a squeeze-out, expression and button-proof manner and whether they can be used by punching them. The answer to the first question is that the respective hollow body elements are now formed as rivet elements, in such a way that the hollow cylindrical projection is crimped after insertion of the projection through a hole in the sheet metal part to a Nietbördel. How this can be done is based on a pre-punched sheet metal part 280 'in Fig. 14B shown, wherein the hole 500 is provided in the bottom region of a bead 502. This is a pre-punched sheet metal part. After the introduction of the hollow cylindrical projection through the hole 500 in the sheet metal part, the hollow cylindrical projection forming the rivet section is crimped by means of the rivet die 504 to the rivet bead 506, which surrounds the sheet metal part in the edge region of the perforation 500 in a between the Nietbördel 506 and the bottom surface of the annular recess 212 formed in the broad side 3 annular groove 508 receives by clamping.

Although the hollow cylindrical projection of the hollow body element according to the invention is not provided with an undercut, it can still be self-piercing attached to a sheet metal part, if this is done in two stages. In a first stage or station, the hollow cylindrical projection is used with a suitable punching die, which is arranged on the other side of a sheet metal part to a hole in the sheet metal part punching and punching through the middle passage of the punching die (not shown). Thereafter, the hollow body element in the sheet metal part "hang", due to the hole reveal of the hollow cylindrical projection or anti-rotation features or ribs, if they engage in the hole edge. In a second stage or station, the rivet section formed by the hollow-cylindrical projection with a suitable rivet die, such as, for example, the rivet die of the Fig. 14C , flanged to a rivet bead.

However, the shape of the hollow body element according to the invention also makes it possible to simplify the follow-on composite tool. Since the undercut on the hollow projection is missing, the previously third station C of the progressive tool, in which the flattening of the hollow projection to produce the undercut, done, no longer required so that this station can be omitted with a corresponding simplification of the progressive tool. The resulting form of the progressive compound tools is in the Fig. 15 and 16 shown. The previously used reference numerals of Fig. 2 and 3 are in the Fig. 15 and 16 where appropriate have been used and will not be further described, since the previous description also applies to these corresponding features or parts.

This simplification means that only one forming station (station A) is required, namely the station where the wrapping process takes place, at which an elongation, ie an elongated extension of the profile strip, which is undesirable, can take place. In the remaining stations B and D, in which the punching process or the singling process take place, there is no elongation of the profile strip. These operations in the workstations B and D mean that the corresponding workstations B and D are not considered to be forming stations.

A further simplification of the follow-on composite tool is possible, and indeed the penetration process can take place outside the follow-on composite tool, for example in a rolling mill according to the Figs. 19A to 19C or the FIGS. 20A to 20C or the Figs. 21A to 21C , which will be explained later. In such an arrangement, the rolling mill can be coupled with the progressive tool, in the sense that the rolling mill feeds the profile strip directly to the follow-on composite tool. This is not required. The rolling mill can provide a profile strip with the necessary enforcements as an intermediate, which can be fed in lengths or in the form of a roll to the progressive die. The rolling can be done in a different factory than the further production in the progressive tool. If the penetration station is not present in the progressive tool, then no forming station is present and the problem of elongation no longer exists. This represents an optimal solution.

If the push-through station A is removed from the follow-on composite tool or is not installed at all, the follow-on composite tool is designed as in FIGS Fig. 17 and 18 shown. The previously used reference numerals of Fig. 2 and 3 are also in the Fig. 17 and 18 where appropriate have been used and will not be further described, since the previous description also applies to these corresponding features or parts.

Both Figs. 19A to 19C the rolling mill is designed to produce from an incoming profile strip 1 with an at least substantially rectangular cross section with a first broad side 2 and an opposite broad side 3 an outgoing profile strip 1 'of regularly alternating profile sections, the incoming strip for the progressive tool Fig. 17 and 18 forms. To this The purpose is the outgoing profile strip 1 'of alternating profile sections, which consist of first profile sections, which have at least substantially the cross-sectional shape of the incoming profile strip 1, and second profile sections, which are made of the incoming profile strip 1 and each have a cylindrical recess 208 at the first Have broad side and a hollow cylindrical, surrounded by an annular recess 212 projection 210 on the second broad side 3.

The rolling mill consists of a first roller 600 and a second roller 602, which are disk-shaped, but only portions of which are shown, in a perspective view in FIG Fig. 19A partially in a side view and in a radial section plane in FIG Fig. 19B and in an enlarged view in the region of the clamping gap in Fig. 19C (where the drawings of the FIGS. 20A to 20C and 21A to 21C are drawn accordingly). The rollers 600 and 602 are synchronized with each other and run in opposite directions of rotation 604 and 606. The incoming profile strip 1 is formed in a gap region 608, ie in the nip 610, between the rollers. The first roller 600 has a plurality of regularly spaced-apart projections 612 having a shape complementary to that of the cylindrical recess 208. The second roller 602 also has a plurality of mold portions 614 arranged at the same intervals as the projections of the first roller, each having a central portion, a shape 616 complementary to the shape of the hollow cylindrical projections 210, and a the central portion surrounding annular projection 618 having a shape which is complementary to the shape of the hollow cylindrical projection 210 surrounding annular recess 212.

In the rolling mill of FIGS. 20A to 20C 21A to 21C, the rollers are similarly configured except that the roller 602 lacks a molding protrusion such as 618 of FIG Fig. 19C , which leads to the formation of an annular recess in the profile strip. This means that the annular recess 212, which is desired for the hollow body elements, must be produced in the progressive tool, for example. By combining the formation of the annular recess 212 with the punching process (and thereby contribute to the correction of the wall of the perforation) or in that this takes place in another workstation, for example in an additional forming station.

In all rolling mills, it is beneficial if the protrusions 612 of the first roll 600 and the mold portions 614 of the second roll 602 have clearances such as 620, i. a somewhat spherical shape, which differs from a circular cylindrical shape, which ensure that a clean rolling movement takes place in the rollers, i. No collisions of the rollers with the profile strip can take place when leaving the expiring profile strip.

The volume of profile strip material displaced by each projection of the first roller should advantageously at least substantially correspond to the material volume of the material displacement on the side of the second roller, i. the volume, which is composed as follows: the volume of the hollow cylindrical projection 210 plus the volume of a bottom portion of the projection extending beyond the second broad side and minus the volume of any surrounding annular recess 212.

Finally, the projections 612 of the first roller 600 and / or the moldings 614 of the second roller may be replaced by respective inserts of the respective ones Rollers 600 and 602 are formed, as in the Fig. 19 to 21 shown, with only in Figs. 21A to 21C the moldings 614 are not realized as inserts. The use of inserts facilitates the replacement of worn or broken inserts without having to replace the entire roller

Although the present invention is intended for the production of rectangular or square elements in the outer contour, it could also be used for the production of polygonal, oval or circular elements in the outer contour or of another shape, provided the tools used are designed to be the profile strip to produce the desired contour shape, for example by the use of appropriately designed punching tools.

1. a) dass in einem ersten Schritt ausgehend von einem im Querschnitt rechteckigen Profil 1 ein Durchsetzvorgang durchgeführt wird, der zu einer zylindrischen Vertiefung 208 an einer ersten Breitseite 2 des Profils und einem hohlzylindrischen Vorsprung 210 an einer zweiten der ersten Breiteseite 2 gegenüber liegenden Breitseite 3 des Profils führt, der von einer ringförmigen Vertiefung 212 umgeben ist,
2. b) dass in einem zweiten Schritt ein zwischen dem Boden 214 der zylindrischen Vertiefung und dem Boden 216 des hohlzylindrischen Vorsprungs 210 verbleibender Steg 218 zur Ausbildung eines durchgehenden Loches 204 durchlocht bzw. herausgestanzt wird,
3. c) dass in einem dritten Schritt die Hohlkörperelemente 200 vom Profil abgetrennt und gegebenenfalls mit Gewinde 206 versehen werden.

Thus, according to the invention, a method is provided for producing hollow body elements 200, such as nut elements, for attachment to components usually made of sheet metal 280, in particular for the production of hollow body elements with an at least substantially square or rectangular outer contour 202, by cutting individual elements from one in the form of a Profile bar 1 or a roll present profile after pre-punching holes 204 in the profile, optionally with subsequent formation of a threaded cylinder 206 using a progressive tool 10 with multiple workstations A, B and D or B and D, in which respective operations are performed. The process according to the invention is characterized by the following steps:

1. a) that in a first step, starting from a rectangular cross-section profile 1, a penetration process is performed, which leads to a cylindrical recess 208 at a first broad side second the profile and a hollow cylindrical projection 210 on a second of the first width side 2 opposite broad side 3 of the profile leads, which is surrounded by an annular recess 212,
2. b) in a second step, a web 218 remaining between the bottom 214 of the cylindrical recess and the bottom 216 of the hollow cylindrical projection 210 is pierced or punched out to form a through hole 204,
3. c) that in a third step, the hollow body elements 200 separated from the profile and optionally provided with thread 206.

The penetration process can, as explained above, in the progressive tool or in an upstream operation, for example in a rolling mill, take place.

During the passage of step a), the diameter of the cylindrical recess 208 and the inner diameter of the hollow cylindrical projection 210 should be at least substantially equal.

When piercing the web according to step b), a hole 204 is preferably produced with a diameter which corresponds at least substantially to the diameter of the cylindrical recess 208 and the inner diameter of the hollow cylindrical projection 210.

In the production of the hollow cylindrical projection 210, this is preferably carried out so that it projects beyond the second broad side of the profile.

During the penetration process according to step a), an annular elevation 260 can be formed on the first broad side (2) of the profile around the cylindrical depression 208.

During the penetration process according to step a), anti-rotation features 272 can be formed on the outside of the hollow-cylindrical projection 210 and / or on the inside in the region of the annular recess 212 about the hollow-cylindrical projection 210.

The anti-rotation features may be formed by ribs 272 and / or grooves on the radially outer side of the hollow cylindrical projection 210.

The anti-rotation features are preferably formed by ribs 272 extending axially along a portion of the hollow cylindrical projection 210 between the bottom of the annular recess 212 and a location between the second broad side 2 of the profile and the free front end of the hollow cylindrical projection.

In this case, the anti-rotation ribs 272 may have a radial width that corresponds at least substantially in the range between 40% and 90% of the maximum radial depth of the undercut 244.

Notwithstanding the previous method, in step a), also starting from a rectangular in cross-section profile 1, a molding operation can be performed in which on the first broad side 2 of the profile 1 optionally no cylindrical recess 208 is provided, but on the second broad side 3 of the profile 1 to a preferably polygonal in plan view, in particular square recess 212 'on the second Broad side 3 of the profile that surrounds the hollow cylindrical projection 210, which is partially formed from the material displaced by the formation of the recess 212 'and partially from the displaced by the formation of the cavity of the hollow cylindrical projection 210 material, wherein the recess 212' with one or more obliquely provided to the central longitudinal axis of the hollow body member annular surface or surfaces is provided and in the second step b) the material between the first broad side 2 of the profile 1 and the bottom 216 of the hollow cylindrical projection 210 to form a through hole 204th pierced or punched out.

An inventive hollow body element for attachment to a usually made of sheet metal component 280 having a particular at least substantially square or rectangular outer contour, with a first broad side 2 and a second broad side 3, with a hollow cylindrical projection 210 which projects beyond the second broad side 3 and of an annular recess 212 is surrounded in the second broad side and with a hole 204 which extends from the first broad side 2 through the hollow cylindrical projection 210 and punching section 222, wherein the hole optionally has a threaded cylinder 206, characterized in that anti-rotation features 272 outside of the hollow cylindrical projection 210 and / or inside in the region of the annular recess 212 are formed around the hollow cylindrical projection 210 around and that no undercut on the hollow cylindrical projection is provided.

The anti-rotation features are preferably formed by ribs 272 and / or grooves on the radially outer side of the hollow cylindrical projection 210.

The anti-rotation features may be formed by ribs 272 extending in the axial direction along the hollow cylindrical projection 210.

The anti-rotation ribs 272 may have a radial width which is at least substantially in the range between 10% and 60% of the wall thickness of the hollow cylindrical projection 210.

The anti-rotation features may also be provided in the form of radially extending ribs bridging the annular recess. An execution of this kind is the Figs. 22A-22D which will be explained later.

In addition, the anti-rotation features can be provided in the form of inclined anti-rotation ribs extending in the radial direction over the annular recess and in the axial direction along the hollow cylindrical projection.

Furthermore, the anti-rotation features can be provided in the form of depressions, which are arranged in the inclined surface of the annular recess.

The second broad side 3 is preferably located radially outside the annular recess 212 in a plane, i. Apart from any curves or chamfers at the transitions in the side edges of the hollow body member, and thus has no beams, grooves or undercuts in the area outside of the annular recess 212.

The annular recess 212 is preferably made with an outer diameter which is only slightly smaller than the smallest transverse dimension of the in plan view rectangular hollow body member 200, whereby the annular recess with the second broad side of the profile at the narrowest points in the plane of the second broadside remaining webs in the range of 0.25 and 1 mm, preferably of about 0.5 mm.

Furthermore, the invention provides a hollow body element for attachment to a usually consisting of sheet metal component 280, with a particular at least substantially square or rectangular outer contour, with a first broad side 2 and a second broad side 3, with a hollow cylindrical projection, over the second broad side 3 and surrounded by an annular recess 212 'in the second broad side and with a hole 204 which extends from the first broad side 2 through the hollow cylindrical projection or through the punching section 210, wherein the hole optionally has a threaded cylinder 206, and the element is characterized in that the annular recess 212 'in plan view is polygonal and in particular square, and that the annular recess 212' is provided with one or more obliquely to the central longitudinal axis of the hollow body member surface or surfaces and the hollow cylindrical projection 210th no e has undercut.

An assembly part according to the invention consists of a hollow body element 200 of the abovementioned type according to the invention, which is attached to a component, for example a sheet metal part 280, wherein the material of the component or the sheet metal part 280 on the surface of the annular recess 212 of the hollow body element, on the surface of Anti-rotation features 272 and applied to the surface of the flanged to a Nietbördel hollow cylindrical projection 210.

In this case, the axial depth of the annular groove 282 in the sheet metal part depending on the length of the hollow cylindrical projection 210 and the thickness of the sheet metal part 280 is selected so that the Nietbördel does not or only slightly protrudes beyond the side of the sheet metal part, which faces away from the body of the hollow body member 200 and in the region below the second broad side 3 of the hollow body element around the annular recess 212 of the hollow body element is present.

The second broad side 3 of the hollow body element 200 in the region around the annular recess 212 of the hollow body element 200 is preferably at least substantially not or at most slightly pressed into the sheet material.

A follow-on composite tool according to the invention for producing hollow body elements 200, such as nut elements, for attachment to components usually made of sheet metal 280, in particular for producing hollow body elements with an at least substantially square or rectangular outer contour 202, by cutting individual elements from one in the form of a profile bar or a Wickels present profile 1 after prior punching of holes 204 in the profile, optionally with subsequent formation of a threaded cylinder 206, wherein in each workstation for the profile or for several juxtaposed profiles each two treatments for each stroke of the progressive tool are simultaneously feasible, characterized characterized in that in a workstation (B) a hole process and in a downstream workstation (D) the separation of two hollow body elements of the or each profile by means of the Abschlagstemp els is feasible.

In this case, in a first workstation (A) an enforcing process can be carried out, for example to form a cylindrical recess 208 on a first broad side of a cross-sectionally at least substantially rectangular profile 1 and a hollow cylindrical, surrounded by an annular recess 212 projection on a second the first broadside opposite broad side of the profile.

In this case, the piercing operation for piercing a remaining after the piercing operation between the bottom of the cylindrical recess 208 and the central passage of the hollow cylindrical projection web is performed.

The follow-on composite tool is designed in a variant to work with an incoming profile strip 1 with an at least substantially rectangular cross-section with a first broad side 2 and an opposite broad side 3, consisting of regularly alternating profile sections of the profile strip 1 and profile sections, from the profile strip 1 and each having a cylindrical recess 208 on the first broad side and a hollow cylindrical, surrounded by an annular recess 212 projection 210 on the second broad side 3 have.

As mentioned above, with a hollow body element 200 according to the invention, it is also possible to execute the anti-rotation ribs 272 in such a way that they bridge the annular groove 212 in the radial direction. Such a design of a hollow body element 200 is in the Figs. 22A-22D shown. The only significant difference to the element according to Figs. 13A-13D is that the anti-rotation ribs 272, as shown here, bridge the annular groove 212 in the radial direction, wherein the material that the anti-rotation ribs 272 in this Design forms over clear radii in the rivet section 210 and in the bottom area and in the outer oblique side of the annular recess 212 passes. The tops of the anti-rotation ribs 272 in Fig. 22D are slightly set back from the second broad side 3 of the element, but can also be flush with this side. Again, it can be seen that the inner cylindrical side 288 of the cylindrical rivet portion 210 has an inner diameter which is slightly larger than the outer diameter of the thread 206, on the one hand in the riveted state, the insertion of a screw in the thread 206, in Fig. 22C Coming from below, here too, the inner diameter 288 forms the thread inlet via a conical region 288 "and merges into the thread, which also serves to center a screw when it is inserted into the thread 206.

In this embodiment, the radius on the outer side of the cylindrical rivet portion 210 is somewhat more pronounced than in the embodiment according to FIG Figs. 13A-13D , The inner cone-shaped surface 288 ', however, is smaller. Here it is shown slightly rounded, but it could also be performed in a conventional manner as a cone-shaped cutting surface.

In the Fig. 22C one sees the anti-rotation ribs 272 left and right of the cylindrical Nietabschnitts in an oblique side view, wherein the hatched representation represents a perspective view of the radii with which the material of the anti-rotation ribs 272, behind the plane of the sectional drawing of Fig. 22C lie, in the inclined surface of the axial groove or the annular recess 212 passes. A possible way of attaching the hollow body element according to Figs. 22A-22D to a sheet metal part is in the drawings of Figs. 23A-23D for a relatively thin sheet metal part 280 'and in the Figs. 24A-24D for a shown relatively thick sheet metal part. The attachment itself is similar to the procedure already used in connection with the Figs. 14A-14D has been described, ie, also with the aid of a die such as 504, in which case the die in addition to the central post area or the middle elevation according to Fig. 14C , which is responsible for the formation of the Nietbördels 506 around this central post around a square in plan view survey, with a cross-sectional shape corresponding to the shape of the recess 510 according to Fig. 23B and a shape in plan view complementary to the circumferential shape of the groove 510 according to FIG Fig. 23D , This in plan view square shape of the outer elevation of the die leads just to the recess 510 according to Figs. 23A-23D respectively. Figs. 24A-24D and at the same time to the corresponding elevation 512 in these figures, which has a corresponding square shape and the hollow body member 200 in the region of the connection to the sheet metal part 280 'eng tight. As a result, an additional security against rotation is created, ie in addition to the security against twisting, which arises through the ribs 272 (in the Figs. 23A-23D or 24A-24D not shown, but available there). In some circumstances, the anti-rotation ribs 272 could be omitted or made less tall and the square boss 512, which includes the outside of the hollow body member 200, used as the sole anti-rotation feature.

However, the elevation 512 in plan view also ensures a visually appealing transition of the lower side of the hollow body element 200 into the sheet metal part 280 '.

By comparing the Figs. 23A-23D and 24A-24D It can be seen that one and the same hollow body element 200 can be used with sheet metal parts 280 'of different thicknesses and nevertheless ensures a high-quality connection to the sheet metal part 280'. In this way it succeeds, for example with only two different embodiments of the hollow body member 200 in terms of different lengths of the hollow rivet portion 210 a sheet thickness range between, for example, 0.6 mm and 3.5 mm (without limitation) cover. It is also advantageous that the underside of the sheet metal part in the region of the element and the underside of the Nietbördels 506 lies with the underside of the sheet metal part outside of the element in a plane, which is favorable for the screwing of another component on the underside of the sheet metal part. This can be achieved no matter what thickness of the sheet metal part is within the allowable range for the once fixed length of the rivet section.

The method for producing the hollow body element 200 according to Figs. 22A-22D corresponds largely to the previously described method and will now be briefly using the Figs. 25A-25F or 26 and 27 explained in more detail.

Referring to the drawings of Figs. 25A-25F you look in Fig. 25A in that the profile strip from which the elements are made is a substantially rectangular strip, but the side surfaces 7 and 8 are slightly inclined relative to one another, ie inclined, in such a way that they face each other in the region of the first broad side 2 of the profile have a smaller distance than in the region of the second broad side 3 of the profile. This results from the hatched area of the profile strip 1 in Fig. 25A which represents the cross section through the strip.

The Fig. 25B shows the profile strip after performing the clinching operation, in which the cylindrical recess 208 is formed with radius 230 in the first broad side 2 of the profile and the cylindrical rivet portion 210 and the surrounding annular groove 212 in the second broad side 3 of the profile is generated. Although in the presentation of the Fig. 25B not to be seen, also the anti-rotation ribs 272, which bridge the annular groove 212, miterzeugten in this first forming step. Furthermore, notches, such as 514, are generated in the broad side 3 of the profile strip, which run perpendicular to the longitudinal direction of the profile strip, ie from one narrow side 7 to the other narrow side 8.

These notches form weakenings that facilitate the subsequent separation of the individual elements from the profile strip. They form in Fig. 25B the boundary of the shown central part of the strip, which later forms a hollow element such as 200, where to the left of the left notch 514 part of another hollow body element and right of the right notch 514 part of a still further hollow body element 200 can be seen.

The progressive compound tool for producing the element according to Figs. 22A-22D corresponds to the in the Figs. 25A-25F and described in this context manufacturing steps and is in the Fig. 26 and in the relevant area of the progressive tool on a large scale in Fig. 27 shown.

The progressive tool of the Fig. 26 or 27 generally corresponds to the progressive tool according to Fig. 15 and 16 and, as explained above, the same reference numerals are used for corresponding parts or parts with the corresponding functions for this reason. In this description of the progressive tool according to Fig. 26 and 27 are essentially only the significant differences compared to the progressive tool according to Fig. 15 and 16 or the other follow-on composite tools already described.

While in the progressive tool the Fig. 15 and 16 the puncture punches 64, 66 below the profile strip 1 and the corresponding Matrices 92, 94 are arranged above the profile strip 1 are in the example in the Fig. 26 and 27, the puncturing punches 64, 66 arranged above the profile strip 1, while the corresponding dies 92, 94 are located below the profile strip. In this case, the support of the piercing dies 92, 94 in the embodiment according to Fig. 26 or 27 taken slightly different than in the embodiment according to Fig. 15 or 16. Here, too, the matrices are arranged in a fixed position in the lower tool.

The purpose of the previously mentioned inclined arrangement of the side surfaces 7 and 8 of the profile strip is that the profile strip is stretched in the upper area adjacent to the cylindrical cavity 208 generated by the puncturing punches 64, 66 by the puncturing punches 64, 66 in the width, whereby the narrow sides 7 and 8 assume a position perpendicular to the upper and lower broad sides 2 and 3, which then ensure proper guidance of the profile strip on the way through the progressive tool.

According to the progressive tool according to Fig. 15 and 16 are in the embodiment according to Fig. 26 and 27 the punches 84 and 86 are arranged above the profile strip 1, while the corresponding dies 100, 102 are located below the profile strip 1.

As a further station in the progressive tool according to Fig. 26 and 27 there are provided two expansion dies 704, 706 which serve to expand the cylindrical rivet portion 210 and the end formation of the expanded hollow cylindrical portion 288 with the conical portion 288 "forming the thread entry and the tapered entry portion 288 'below the profile strip Above the profile strip, there are then two punches 700, 702, which are in the already formed cylindrical recess 208 engage when closing the press and intercept the forces acting from the Aufweitmatrizen 704, 706 in the direction of the longitudinal axis 226 of the individual hollow body elements. They can also be used for correcting the shape of the hollow body element in the region of the thread outlet and / or for calibrating the inner diameter of the region 208 or the through hole 204 before carrying out the threading process, which only after separation of the individual elements from the profile strip by the knock-stamp 222 and removal of individual hollow body elements takes place from the press.

In deviation from the previous progressive tool according to Fig. 15 and 16 no spring-loaded cam is used here for the removal of the elements from the area of the tee-off punch, but instead an insertable guide channel 118 is used which leads the elements leaving the follow-on composite tool in the running direction of the profile strip out of the area of the tee-off punch. The second hollow body member 200 ', which is separated at each stroke of the press from the profile strip is led out as before via a through hole 28 in the tee die 30 and an enlarged bore 38 of the lower plate 12 and can for example after leaving the plate 12 or within the Plate 12 are led out laterally from the press via a lateral slide.

In this embodiment, the small surveys at reference numeral 708 are observed. These bumps serve to form notches such as 514. Note also the item numbered 710. This is a position sensor that dips into a cylindrical cavity 208 to ensure that the profile strip has been processed properly so far and is in the right place in the progressive tool.

If the probe 710 does not dip into such a cavity 208 at the intended amount every stroke of the press, it encounters, for example, the upper broad side 2 of the profile strip adjacent to such a cavity or in the absence of such a cavity because it simply does not exist, For example, since the puncturing punches 64, 66 are worn or broken, the feeler 710 is displaced upward against the force of the spring 714 acting on the collar 712 of the probe 710 when closing the press, coming close to the force of the spring 714 Proximity sensor 716, which emits a corresponding signal that serves to immediately stop the press. The cause of the fault can then be investigated and the press put back into service after the required correction or repair has been carried out.

During the opening stroke of the press, the upper tool must be raised so far that the puncture punches 64, 66, the probe 710, the punches 84, 86 and the Abstützstempel 700, 702 and the tee punches 22 come free from the top 2 of the profile strip, said the profile strip must be raised to the extent that it comes free of projecting parts of the lower tool, such as the Durchrißmatrizen 92, 94, the notch-generating projections 708, the Lochmatrizen 100, 102 and the fixed Aufweitmatrizen 704, 706 and the tee die 30. For each Stroke the press of the profile strip is displaced by a length corresponding to the length of two hollow body elements 200 to the right according to the arrow 720. In this embodiment, each station corresponds to a length which is an integer multiple of the length of a single hollow body member 200. It will be here, as shown in the drawings, several empty stations provided to create space for the individual tools of progressive die tool. Again, a significant deformation is actually made only in the area of the puncturing punches 64, 66 and the clinching 92, 94, so that problems with the elongation of the profile strip within the progressive tool are not expected, especially as a part of the strain, in the field of puncture and the penetration matrices takes place, is taken up by the inclination of the sides 7, 8 of the profile strip and therefore does not affect an elongation of the profile strip.

In all embodiments, as an example of the material of the profile and the functional elements produced therefrom, all materials can be mentioned which reach the strength values of class 8 according to ISO standard or higher in the context of cold working, for example a 35B2 alloy according to DIN 1654 formed fasteners are, inter alia For all commercially available steel materials for drawable sheet metal parts as well as for aluminum or its alloys. Also, aluminum alloys, especially those with high strength, can be used for the profile or functional elements, e.g. AlMg5. Profiles or functional elements of higher-strength magnesium alloys such as, for example, AM50 come into question.

Although the present invention is intended for the production of rectangular or square elements in the outer contour, it could also be used for the production of polygonal, oval or circular elements in the outer contour or of another shape, provided the tools used are designed to be the profile strip to produce the desired contour shape, for example by the use of appropriately designed punching tools.

Claims (45)

1. Method for the manufacture of hollow body elements (200) such as nut elements for attachment to components normally comprising sheet metal (280), in particular for the manufacture of hollow body elements having an at least substantially square or rectangular external outline (202), by cutting individual elements by length from a section present in the form of a bar section (1) or of a coil after prior piercing of holes (204) into the section, optionally with subsequent formation of a threaded cylinder (206) by using a progressive tool (10) having a plurality of working stations (A, B and D; B and D) in which respective operations are carried out, characterized by the following steps:

   a) that in a first step, starting from a section (1) of rectangular cross-section, an upsetting process is carried out which leads to a cylindrical recess (208) at a first broad side (2) of the section and to a hollow cylindrical projection (210) forming a rivet section at a second broad side (3) of the section lying opposite to the first broad side (2), with the projection being surrounded by a ring-like recess (212),

   b) that in a second step a web (218) remaining between the base (214) of the cylindrical recess and the base (216) of the hollow cylindrical projection (210) is pierced or punched out to form a through-going hole (204),

   c) that in a third step the hollow body elements (200) are separated from the section and are optionally provided with a thread (206).
2. Method in accordance with claim 1,
   characterized in that
   during the upsetting process of step a) the diameter of the cylindrical recess (208) and the internal diameter of the hollow cylindrical projection (210) are made at least substantially the same.
3. Method in accordance with claim 1 or claim 2,
   characterized in that
   during the upsetting process of the step a) or during the piercing process of the step b) the opening of the cylindrical recess (208) at the first broad side of the section is executed with a rounded or chamfered entry edge (230).
4. Method in accordance with one of the preceding claims,
   characterized in that
   during the upsetting process of step a) or during the piercing process of step b) the mouth of the hollow cylindrical projection (210) is provided at its free end with a rounded or chamfered run-out edge (234).
5. Method in accordance with one of the preceding claims,
   characterized in that
   during the piercing of the web in accordance with step b) a hole (204) is produced with a diameter which at least substantially corresponds to the diameter of the cylindrical recess (208) and to the internal diameter of the hollow cylindrical projection (210).
6. Method in accordance with one of the preceding claims,
   characterized in that
   during the upsetting process of the first step a) the free end of the hollow cylindrical projection (210) is provided at the outside with a chamfer (236).
7. Method in accordance with one of the preceding claims,
   characterized in that
   during the upsetting process of the first step a) the ring recess (212) is provided with a ring-like base region (238) which stands at least approximately in a plane parallel to the first and second broad sides (2, 3), merges at the radially inner side by an at least substantially rounded transition (240) into the outer side of the hollow cylindrical projection (210) and merges at the radially outer side into a conical surface (242).
8. Method in accordance with claim 7,
   characterized in that
   the conical surface (242) of the ring recess (212) has an enclosed cone angle in the range between 60 and 120°, preferably of approximately 90°.
9. Method in accordance with one of the preceding claims,
   characterized in that
   the transition from the ring-like region (240) of the ring recess into the conical surface (242) is rounded.
10. Method in accordance with one of the claims 7 to 9,
    characterized in that
    the run-out of the conical surface (242) of the ring recess into the second broad side (3) of the section is rounded.
11. Method in accordance with one of the preceding claims,
    characterized in that
    during manufacture of the hollow cylindrical projection (210) this is designed so that it projects beyond the second broad side of the section and in that the hollow cylindrical projection (210) is executed with a broadened hollow cylindrical region (288), the diameter of which is preferably slightly larger than the outer diameter of the thread (206), with the embodiment with a broadened hollow cylindrical region being able to be carried out by a further manufacturing step in the form of an expansion step between the second and third steps.
12. Method in accordance with one of the preceding claims,
    characterized in that
    the ring recess (212) is executed with an outer diameter which is made only somewhat smaller than the smallest transverse dimension of the hollow body element (200) which is rectangular in plan view, whereby the ring recess forms webs (284, 286) with the second broad side of the section at the narrowest points in the plane of the second broad side, said webs having a width in the range of 0.25 to 1 mm, preferably of approximately 0.5 mm.
13. Method in accordance with one of the preceding claims,
    characterized in that
    during the upsetting process in accordance with step a) a ring-like raised portion (260) is formed on the first broad side (2) of the section around the cylindrical recess (208).
14. Method in accordance with one of the preceding claims,
    characterized in that
    during the upsetting process in accordance with the step a) features (272) providing security against rotation are formed externally at the hollow cylindrical projection (210) and/or internally in the region of the ring recess (212) around the hollow cylindrical projection (210) and/or in that points of weakening, for example in the form of notches (514) which extend from one longitudinal side (7) to the other longitudinal side (8) of the sectional strip (1) and are arranged in the second broad side (3) of the sectional strip (1), are formed at points between adjacent hollow body elements (200) of the sectional strip.
15. Method in accordance with claim 14,
    characterized in that
    the features providing security against rotation are formed by ribs (272) and/or by grooves at the radially outer side of the hollow cylindrical projection (210).
16. Method in accordance with claim 14 or 15,
    characterized in that
    the features providing security against rotation are formed by ribs (272) which extend in the axial direction along a part of the hollow cylindrical projection (210) between the base of the ring-like recess (212) and a point between the second broad side (2) of the section and the free end of the hollow cylindrical projection.
17. Method in accordance with claim 14,
    characterized in that
    features providing security against rotation in the form of radially extending ribs (272) which bridge the ring recess (212) are formed in the step a).
18. Method in accordance with claim 14 or claim 17,
    characterized in that
    the features providing security against rotation are made in the form of obliquely set ribs providing security against rotation which extend in a radial direction over the ring recess and in an axial direction along the hollow cylindrical projection
19. Method in accordance with claim 14 or claim 17,
    characterized in that
    the features providing security against rotation are made in the form of ribs providing security against rotation which extend in the radial direction over the ring recess and in the axial direction along the hollow cylindrical projection.
20. Method in accordance with claim 14,
    characterized in that
    features providing security against rotation are made in the form of recesses and indeed in the step a) or in the step b) and are arranged in the obliquely set surface of the ring recess.
21. Method in accordance with claim 1,
    characterized in that
    in deviation from claim 1 a forming process is carried out in the step a), likewise starting from a section (1) which is rectangular in cross-section in which optionally no cylindrical recess (208) is provided at the first broad side (2) of the section (1) but which leads at the second broad side (3) of the section (1) to a recess (212') which is preferably polygonal and in particular square in plan view and which surrounds the hollow cylindrical projection (210) which is partly formed of the material displaced through the formation of the recess (212') and partly from the material displaced through the formation of the hollow space of the hollow cylindrical projection (210), with the recess (212') being provided with one or more ring surfaces which are obliquely set to the central longitudinal axis of the hollow body element and in the step b) the material between the first broad side (2) of the section (1) and the base (216) of the hollow cylindrical projection (210) is pierced or punched out to form a through-going hole (204).
22. Hollow body element for attachment to a component (280) normally comprising sheet metal (280) and having an in particular at least substantially square or rectangular external outline, having a first broad side (2) and a second broad side (3), having a hollow cylindrical projection (210) without undercut which projects beyond the second broad side (3) and is surrounded by a ring recess (212) in the second broad side and also having a hole (204) which extends from the first broad side (2) through the hollow cylindrical projection which forms a rivet section and/or through the piercing section (222), with the hole optionally having a threaded cylinder (206),
    characterized in that
    features (272) providing security against rotation are formed outwardly at the hollow cylindrical projection (210) and/or inwardly in the region of the ring recess (212) around the hollow cylindrical projection (210).
23. Hollow body element in accordance with claim 22,
    characterized in that
    the features providing security against rotation are formed by ribs (272) and/or grooves at the radially outer side of the hollow cylindrical projection (210).
24. Hollow body element in accordance with claim 22 or claim 23,
    characterized in that
    the features providing security against rotation are formed by ribs (272) which extend in the axial direction along the hollow cylindrical projection (210).
25. Hollow body element in accordance with claim 24,
    characterized in that
    the ribs (272) providing security against rotation have a radial width which lies at least substantially in the range between 10% and 60% of the wall thickness of the hollow cylindrical projection (210).
26. Hollow body element in accordance with claim 22,
    characterized in that
    features providing security against rotation are provided in the form of radially extending ribs (272) which bridge the ring recess (212).
27. Hollow body element in accordance with claim 22 or claim 26,
    characterized in that
    the features providing security against rotation are provided in the form of ribs providing security against rotation which extend in the radial direction across the ring recess and in the axial direction along the hollow cylindrical projection (210).
28. Hollow body element in accordance with claim 22,
    characterized in that
    the features providing security against rotation are provided in the form of recesses which are arranged in the obliquely set surface of the ring recess.
29. Hollow body element in accordance with one of the preceding claims 22 to 28,
    characterized in that
    the second broad side (3) lies radially outside of the ring recess (212) in a plane, i.e. apart from any rounded portions or chamfers at the transitions into the side flanks of the hollow body element, and thus has no bars, grooves or undercuts in the region outside of the ring recess (212).
30. Hollow body element in accordance with one of the claims 22 to 29,
    characterized in that
    the opening of the cylindrical recess (208) at the first broad side of the section is made with a rounded or chamfered entry edge (230).
31. Hollow body element in accordance with one of the claims 22 to 30,
    characterized in that
    the opening of the hollow cylindrical projection (210) is provided with a rounded or chamfered run-out edge (234) at its free end.
32. Hollow body element in accordance with one of the preceding claims 22 to 31,
    characterized in that
    the ring recess (212) is provided with a ring-like base region (238) which stands at least approximately in a plane parallel to the first and second broad sides (2, 3), merges at the radially inner side with an at least substantially rounded transition (240) into the outer side of the hollow cylindrical projection and merges at the radially outer side into a conical surface (242).
33. Hollow body element in accordance with one of the preceding claims 22 to 32,
    characterized in that
    the ring recess (212) is designed with an outer diameter which is only somewhat smaller than the smallest transverse dimension of the hollow body element (200) which is rectangular in plan view, whereby the ring recess forms webs with the second broad side of the section which remain at the narrowest points in the plane of the second broad side, said web being in the range from 0.25 to 1 mm, preferably of approximately 0.5 mm.
34. Hollow body in accordance with claim 22
    characterized in that
    the ring recess (212') is polygonal and in particular square in plan view and in that the ring recess (212') is provided with a plurality of surfaces set obliquely to the central longitudinal axis of the hollow body element which belong to the sheet metal contact surface and run out at the broad side (3).
35. Component assembly comprising a hollow body element (200) in accordance with one of the preceding claims 22 to 34, which is attached to a component, for example to a sheet metal part (280), with the material of the component or of the sheet metal part (280) contacting the surface of the ring recess (212) of the hollow body element at the surface of the features (272) providing security against rotation and also at the surface of the hollow cylindrical projection (210) which has been beaded over to form a rivet bead.
36. Component assembly in accordance with claim 35,
    characterized in that
    the axial depth of the ring groove (282) in the sheet metal part has been selected in dependence on the length of the hollow cylindrical projection (210) and on the thickness of the sheet metal part (280) such that the rivet bead does not project or only fractionally projects beyond the side of the sheet metal part which is remote from the body of the hollow body element (200) and is present in the region beneath the second broad side (3) of the hollow body element around the ring recess (212) of the hollow body element.
37. Component assembly in accordance with claim 35 or claim 36,
    characterized in that
    the second broad side (3) of the hollow body element (200) is at least substantially not pressed into the sheet metal material or is at most fractionally pressed into the sheet metal material in the region around the ring recess (212) of the hollow body element (200).
38. Component assembly in accordance with one of the preceding claims 35 to 37,
    characterized in that
    a trough (510) is provided in the sheet metal part at the rivet bead side of the hollow body element (200) and has a rectangular shape in plan view corresponding to the external outline of the hollow body element (201), with a raised portion (512) having a corresponding shape surrounding the hollow body element at the side of the sheet metal part (280) remote from the rivet bead and serving as an additional security against rotation or as a substitute for other features (272) providing security against rotation.
39. Progressive tool for carrying out the method in accordance with one of the claims 1 to 21 for the manufacture of hollow body elements (200) in accordance with one of the claims 22 to 34 such as nut elements for attachment to components normally comprising sheet metal (280), in particular for the manufacture of hollow body elements having an at least substantially square or rectangular external outline (202), by cutting individual elements to length from a section (1) present in the form of a bar section or of a coil after the prior piercing of holes (204) into the section, optionally with the subsequent formation of a threaded cylinder (206) using a progressive tool having at least two working stations (B and D), wherein in each case two operations can simultaneously be carried out for each stroke of the progressive tool in each working station for the section or for the plurality of sections arranged alongside one another,
    characterized in that
    an upsetting process can be carried out in a first working station (A) for example to form a cylindrical recess (208) at a first broad side of the section (1) which is at least substantially rectangular in cross-section and without a bar and a hollow cylindrical projection surrounded by a ring-like recess (212) and forming a rivet section at a second broad side of the section lying opposite to the first broad side; and in that a piercing process can be carried out in a workstation (B) and the separation of two respective hollow body elements from the or from each section can take place by means of the cutting punch.
40. Progressive tool in accordance with claim 39,
    characterized in that
    the piercing process can be carried out by piercing a web which remains after the upsetting process between the base of the cylindrical recess (208) and the central passage of the hollow cylindrical projection.
41. Progressive tool in accordance with claim 39,
    characterized in that
    it is designed in order to operate with an ingoing sectional strip (1) having an at least substantially rectangular cross-section with the first broad side (2) and a second broad side (3) lying opposite to it and which comprises regularly alternating sectional portions of the sectional strip (1) and sectional portions which are manufactured from the sectional strip (1) and which each have a cylindrical recess (208) at the first broad side and a hollow cylindrical projection (210) surrounded by a ring-like recess (212) at the second broad side (3).
42. Rolling mechanism (600, 602) for use in combination with a progressive tool in accordance with claim 41 and which is designed in order to manufacture, from an ingoing sectional strip (1) having an at least substantially rectangular cross-section with a first broad side (2) and a broad side (3) lying opposite to it, an outgoing sectional strip comprising regularly alternating sectional portions,
    characterized in that
    the outgoing sectional strip (1) comprises alternating section portions which have first sectional portions which have at least substantially the cross-sectional shape of the ingoing sectional strip and second sectional portions which are manufactured from the ingoing sectional strip (1) and which each have a cylindrical recess (208) at the first broad side and a hollow cylindrical projection (210) at the second broad side (3) which is surrounded by a ring-like recess (212); and
    in that the rolling mechanism comprises a first roll (600) and a second roll (602) which rotate synchronized with one another in opposite directions of rotation (604, 606) and which reshape the ingoing sectional strip (1) in a gap region between them, with the first roll (600) having a plurality of projections (612) arranged at regular angular intervals with a shape which is complementary to the cylindrical recess (208) and the second roll (602) likewise having a plurality of shaped parts (614) or shaped regions arranged at the same intervals as the projections of the first roll (600) and which each have a central portion with a shape which is complementary to the shape of the hollow cylindrical projections projecting on the second broad side of the section strip.
43. Rolling mechanism in accordance with claim 42,
    characterized in that
    the projections (612) of the first roll (600) and the shaped parts (614) or shaped regions of the second roll (602) are relieved to ensure that a clean rolling off movement takes place at the rolls, i.e. no collisions of the rolls can take place during a run-out from the running out sectional strip (1').
44. Rolling mechanism in accordance with one of the claims 42 or 43,
    characterized in that
    the volume of sectional strip material displaced by each projection (612) of the first roll (600) corresponds at least substantially to the material volume of the material displacement at the side of the second roll, i.e. to the volume which is composed as follows: the volume of the hollow cylindrical projection (210) plus the volume of a base region of the projection extending beyond the second broad side and less the volume of any ring-like recess (212) surrounding the same.
45. Rolling mechanism in accordance with one of the claims 42 to 44,
    characterized in that
    the projections (612) of the first roll (600) and/or the shaped parts (614) of the second roll (602) are formed by respective inserts of the respective rolls.

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