EP1628788A1 - Method for producing a peripherally closed hollow profiled element - Google Patents

Method for producing a peripherally closed hollow profiled element

Info

Publication number
EP1628788A1
EP1628788A1 EP04729065A EP04729065A EP1628788A1 EP 1628788 A1 EP1628788 A1 EP 1628788A1 EP 04729065 A EP04729065 A EP 04729065A EP 04729065 A EP04729065 A EP 04729065A EP 1628788 A1 EP1628788 A1 EP 1628788A1
Authority
EP
European Patent Office
Prior art keywords
blank
trimming
hollow profile
internal high
way
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP04729065A
Other languages
German (de)
French (fr)
Other versions
EP1628788B1 (en
Inventor
Gerhard Linke
Matthias Schroeder
Jens Schult
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Mercedes Benz Group AG
Original Assignee
DaimlerChrysler AG
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by DaimlerChrysler AG filed Critical DaimlerChrysler AG
Publication of EP1628788A1 publication Critical patent/EP1628788A1/en
Application granted granted Critical
Publication of EP1628788B1 publication Critical patent/EP1628788B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/033—Deforming tubular bodies
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D—WORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D26/00—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces
    • B21D26/02—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure
    • B21D26/053—Shaping without cutting otherwise than using rigid devices or tools or yieldable or resilient pads, i.e. applying fluid pressure or magnetic forces by applying fluid pressure characterised by the material of the blanks

Definitions

  • the invention relates to a method for producing a circumferentially closed hollow profile according to the preamble of patent claim 1.
  • a generic method is known from WO 98/43758 AI.
  • a hollow profile blank of uniform cross-section is inserted into an internal high-pressure forming tool, the engraving of which is related to of the blank has a reduced cross section in the area between the ends thereof.
  • the inserted hollow profile blank is squeezed in this area during the closing process of the forming tool.
  • the resultant retraction of the hollow profile blank manifests itself in an inclined position or a deformation of the end of the blank which is rectilinear at the beginning of the production process and with the end face perpendicular to the longitudinal extension of the blank.
  • the axial stamps provided with a conical sealing area and then docking onto the blank ends can only inadequately seal the blank from the internal high pressure to be generated later.
  • the subsequent expansion process of the blank by means of the high fluid pressure is not completely reliable and so that the hollow profile cannot be produced as desired.
  • the invention has for its object to develop a generic method in such a way that even with strong crushing deformations of the hollow profile blank, which result when the forming tool is closed, a process-reliable production of the hollow profile is made possible.
  • the invention is based on the finding that the deformations that occur when the blank is squeezed can be compensated for by a targeted cutting of the blank ends.
  • the end faces of the ends are flat after being squeezed and with the forming tool completely closed, and are aligned as far as possible perpendicular to the longitudinal extent of the blank.
  • the axial punches can dock onto these ends as if the blank had not been trimmed and had not previously been subjected to any crushing.
  • the axial punches can thus sufficiently seal the blank at both ends against the internal high pressure that is still to be produced, which enables a process-reliable production of the hollow profile.
  • the invention In addition, a cutting collision of the axial ram and the blank otherwise provided with tilted end faces is avoided by the invention, the chips and flags formed thereby having to be removed in a complex manner during a reworking operation after removal of the finished hollow profile.
  • This removal is usually associated with a severing of the sealing sections of the blank ends, so that, according to the invention, such a trimming operation can be dispensed with, in addition to the labor savings, which is expensive to dispose of material waste.
  • the planning in advance of a lost additional length of the blank is no longer necessary, as a result of which, due to the shorter length of the blank, the friction between the blank and the forming tool to be overcome in the subsequent expansion of the blank by means of internal high pressure is considerably reduced.
  • the ends of the blank are trimmed in such a way that the end faces of the ends are beveled in relation to the central axis lying in the squeezing direction and extending transversely to the longitudinal axis of the blank.
  • This trimming form results from the additional knowledge that the deformations of the blank which arise as a result of the squeezing as a function of the squeezing direction lead to an oblique position of the raw end cross section and thus the end face to the axis mentioned, so that the pipe ends are beveled in the opposite direction in the sense of the invention become.
  • an upper circumferential region of the pipe end projects beyond its lower circumferential region in the axial direction.
  • the blank ends are trimmed such that their end faces remain arranged parallel to one another.
  • the end face of one uncut end is tilted upward, so that the lower circumferential area axially projects beyond the upper circumferential area of the end, and the end face of the other untrimmed end tilted downward, the upper peripheral region of the end projecting beyond the lower peripheral region in the axial direction.
  • the blank can therefore before the crimping process at both ends under the same Angle cut in the opposite direction of the tilt.
  • the resulting uniformity of the trimming makes the cutting process easier.
  • the same also applies to a lateral offset of the ends after the pinching has taken place.
  • a particularly preferred embodiment of the invention is, according to claim 4, the special determination of the bevel angle of the bleed, which lies in a range between 6 ° and 10 °, preferably 8 °.
  • the tilt of the end faces which is caused by the squeezing deformation, is almost always in this angular range, so that in the opposite direction an equally large bevel angle of the end face of the end is provided when trimming got to.
  • the end deformation actually occurring as a result of the later squeezing process is determined in a computer simulation, in particular a finite element simulation, and then an optimal snowmaking is used to compensate for the deformation - Contour contour and an optimal bevel angle of the trimming to be carried out.
  • the bevel angle and circumference contour suitable for each component and for each type of crushing can be determined individually with relatively little effort and without the use of numerous, laborious, empirical studies.
  • the ends are trimmed in two dimensions.
  • the exact spatial contour of the blank end is indeed not recorded, however such trimming can be carried out quickly and particularly economically.
  • the ends are trimmed in a three-dimensional contour cut. This can be done, for example, by means of a cutting laser and offers the axially docking axial punch the best possible connection surface, so that an optimal seal is achieved by means of the punch.
  • FIG. 1 is a side half section of a hollow profile blank trimmed on both sides according to the invention in an open forming tool
  • Fig. 2 in a side half-section of the hollow profile blank from Figure 1 after the squeezing process with closed internal high pressure forming tool.
  • an internal high pressure forming tool 1 which consists of an upper part 2 and a lower part 3.
  • the tool engraving 4, which is formed by both tool parts 2 and 3 and delimits a molding space for a hollow profile blank 5 inserted and to be formed in the tool 1, is designed such that one end 6 of the engraving 4 is arranged offset in height from the other end 7. These two ends 6 and 7 of the engraving 4 have approximately the same diameter in the closed forming tool 1 according to FIG. 2 as the inserted hollow profile blank 5.
  • the engraving 4 is in a central region 8 which connects the two ends 6 and 7 to one another significantly reduced in cross-section.
  • the hollow profile blank 5 in turn has at its two ends 9 and 10 an end face 12 and 13 inclined in the direction of the longitudinal axis 11 of the hollow profile blank 5.
  • the hollow profile blank 5 in which the end faces 12 and 13 of its ends 9 and 10 are arranged parallel to one another, is located entirely within the engraving 4 of the forming tool 1.
  • the taper angle of the end face 12 or 13 to the central vertical axis 18 is 8 °.
  • the ends 9 and 10 of the blank 5 are first trimmed in such a way that beveled end faces 12 and 13 result, these should be beveled as far as possible to the axis lying in the squeezing direction in order to obtain an optimal deformation result which results from the squeezing process and to ensure a clean seal of the axial ram that will later dock for internal high pressure forming.
  • the blank ends 9 and 10 are trimmed in such a way that their end faces 12 and 13 remain parallel to one another.
  • the deformation of the ends 9 and 10 caused by the later squeezing process is determined in a finite element computer simulation and then the suitable trimming contour and the suitable bevel angle are calculated from this.
  • the so truncated hollow profile blank 5 is now inserted 'into the impression 4 of the forming die 1, after which this is closed. Due to the central region 8 constricting the engraving 4, in the closing process of the forming tool 1, the upper partly 2 and the lower part 3 a pinch of the hollow profile blank 5.
  • the central pinch 19, which can be seen from FIG. 2, which shows the forming tool 1 in its closed state, has an effect on the ends 9 and 10 of the hollow profile blank 5 in this way that the end faces 12 and 13 of the blank 5 are perpendicular to its longitudinal extent.
  • the axial punches are then moved up to the ends 9 and 10 of the hollow profile blank 5 and seal them with a conical sealing area.
  • a pressure fluid is now introduced into the hollow profile blank 5 via the axial rams and placed under high pressure. Due to the existing internal high pressure, the hollow profile blank 5 is widened, whereby it lies completely against the engraving 4 of the forming tool 1. The pressure fluid is now released and led out of the now fully formed hollow profile, after which the axial rams are moved back by the forming tool 1. Finally, this is opened and the hollow profile is removed from the engraving 4.
  • the invention has the significant advantage that the straight position of the end faces 12, 13 enables a homogeneous force introduction of the axial punches into the forming area of the internal high-pressure forming process that is to be bulged out, which contributes extraordinarily to the process reliability of the forming process due to the avoidance of undesired wrinkle formation and material thickening based thereon ,

Landscapes

  • Physics & Mathematics (AREA)
  • Fluid Mechanics (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Medicines That Contain Protein Lipid Enzymes And Other Medicines (AREA)

Abstract

The invention relates to a method for producing a peripherally closed hollow profiled element by means of internal high-pressure forming. According to said method, a hollow longitudinal blank (5) is inserted into an internal high-pressure form tool (1) and, during the closing process of the form tool (1), the blank (5) which is fully inserted thereinto is compressed in a region between the two ends (9,10) thereof, whereafter the compressed blank (5) is enlarged into the end shape of the hollow profiled element by means of fluidic internal high pressure. The aim of the invention is to enable a reliable production of the hollow profiled element even in the event of large deformation of the hollow profiled blank (5) resulting during the closing of the form tool (1). To this end, the ends (9,10) of the blank (5) are cut before the compression process, respectively forming a bevelled front surface (12,13), and the cut contour of the ends (9,10) and the bevelling angle (α) are selected in such a way that the ends (9,10) are deformed by means of the compression process such that the front surfaces (12,13) thereof have an essentially plane form and assume a position that is as perpendicular as possible to the longitudinal extension of the blank (5).

Description

Verfahren zur Herstellung eines umfänglich geschlossenen Process for producing a completely closed
Hohlprofilshollow profile
Die Erfindung betrifft ein Verfahren zur Herstellung eines umfänglich geschlossenen Hohlprofils gemäß dem Oberbegriff des Patentanspruches 1.The invention relates to a method for producing a circumferentially closed hollow profile according to the preamble of patent claim 1.
Ein gattungsgemäßes Verfahren ist aus der WO 98/43758 AI bekannt. Hierbei wird ein Hohlprofilrohling gleichförmigen Querschnitts in ein Innenhochdruckumformwerkzeug eingelegt, dessen Gravur einen bzgl . des Rohlings im Bereich zwischen dessen Enden reduzierten Querschnitt aufweist . Dadurch wird der eingelegte Hohlprofilrohling während des Schließvorganges des Umformwerkzeugs in diesem Bereich gequetscht . Der dadurch bedingte Einzug des Hohlprofilrohlings äußert sich jedoch in einer Schiefstellung bzw. einer Verformung des zu Beginn des Herstellungsverfahrens geradlinig verlaufenden und mit der Stirnfläche senkrecht zur Längserstreckung des Rohlings stehenden Endes des Rohlings. Aufgrund der durch das Quetschen veränderten Endenkontur und der Verkippung der Stirnfläche können die mit einem konischen Dichtbereich versehenen, an den Rohlingsenden anschließend andockenden Axialstempel nur unzureichend gegenüber dem später zu erzeugenden Innenhochdruck den 'Rohling abdichten. Dies hat zur Folge, dass der später stattfindende Aufweitvorgang des Rohlings mittels des fluidischen Innenhochdrucks nicht völlig prozesssicher ist und damit das Hohlprofil nicht wie gewünscht hergestellt werden kann.A generic method is known from WO 98/43758 AI. Here, a hollow profile blank of uniform cross-section is inserted into an internal high-pressure forming tool, the engraving of which is related to of the blank has a reduced cross section in the area between the ends thereof. As a result, the inserted hollow profile blank is squeezed in this area during the closing process of the forming tool. The resultant retraction of the hollow profile blank, however, manifests itself in an inclined position or a deformation of the end of the blank which is rectilinear at the beginning of the production process and with the end face perpendicular to the longitudinal extension of the blank. Because of the end contour changed by the squeezing and the tilting of the end face, the axial stamps provided with a conical sealing area and then docking onto the blank ends can only inadequately seal the blank from the internal high pressure to be generated later. As a result, the subsequent expansion process of the blank by means of the high fluid pressure is not completely reliable and so that the hollow profile cannot be produced as desired.
Der Erfindung liegt die Aufgabe zugrunde, ein gattungsgemäßes Verfahren dahingehend weiterzubilden, dass auch bei starken Quetschverformungen des Hohlprofilrohlings, die sich beim Schließen des Umformwerkzeuges ergeben, eine prozesssichere Herstellung des Hohlprofils ermöglicht wird.The invention has for its object to develop a generic method in such a way that even with strong crushing deformations of the hollow profile blank, which result when the forming tool is closed, a process-reliable production of the hollow profile is made possible.
Die Aufgabe ist erfindungsgemäß durch die Merkmale des Patentanspruches 1 gelöst .The object is achieved by the features of claim 1.
Die Erfindung basiert auf der Erkenntnis, dass durch einen gezielten Zuschnitt der Rohlingsenden die beim Quetschen des Rohlings auftretenden Verformungen kompensiert werden können. Durch das erfindungsgemäße Beschneiden der Rohlingsenden wird erreicht, dass nach dem Quetschen und bei völlig geschlossenem Umformwerkzeug die Stirnflächen der Enden eben sind und weitestgehend senkrecht zur Längserstreckung des Rohlings ausgerichtet sind. Infolge der erreichten Stellung der Rohlingsenden können die AxialStempel an diesen Enden andocken, als ob der Rohling unbeschnitten und vorher keiner Quetschung unterzogen worden wäre. Somit können die Axialstempel den Rohling beiderends ausreichend gegenüber dem noch zu erzeugenden Innenhochdruck abdichten, wodurch eine prozesssichere Herstellung des Hohlprofils ermöglicht wird. Zusätzlich wird durch die Erfindung eine spanabhebende Kollision der Axial- Stempel und des ansonsten mit gekippten Stirnflächen versehenen Rohlings vermieden, wobei die dabei entstehenden Späne und Fähnchen in aufwendiger Weise während eines Nacharbeitsgangs nach Entnahme des fertiggeformten Hohlprofils entfernt werden müssten. Dieses Entfernen ist zumeist verbunden mit einem Abtrennen der Abdichtabschnitte der Rohlingsenden, so dass aufgrund der Erfindung eine derartige Beschnittoperation entfallen kann, wobei neben der Arbeitsersparnis aufwendig zu entsorgender Materialabfall eingespart werden kann. Auch ist das Vorabeinplanen einer verlorenen Zusatzlänge des Rohlings nicht mehr vonnδten, wodurch aufgrund der kürzeren Länge des Rohlings die bei der anschließenden AufWeitung des Rohlings mittels Innenhochdruck zu überwindende Reibung zwischen Rohling und Umformwerkzeug erheblich verringert wird.The invention is based on the finding that the deformations that occur when the blank is squeezed can be compensated for by a targeted cutting of the blank ends. By trimming the ends of the blank according to the invention, the end faces of the ends are flat after being squeezed and with the forming tool completely closed, and are aligned as far as possible perpendicular to the longitudinal extent of the blank. As a result of the position of the blank ends being reached, the axial punches can dock onto these ends as if the blank had not been trimmed and had not previously been subjected to any crushing. The axial punches can thus sufficiently seal the blank at both ends against the internal high pressure that is still to be produced, which enables a process-reliable production of the hollow profile. In addition, a cutting collision of the axial ram and the blank otherwise provided with tilted end faces is avoided by the invention, the chips and flags formed thereby having to be removed in a complex manner during a reworking operation after removal of the finished hollow profile. This removal is usually associated with a severing of the sealing sections of the blank ends, so that, according to the invention, such a trimming operation can be dispensed with, in addition to the labor savings, which is expensive to dispose of material waste. Also, the planning in advance of a lost additional length of the blank is no longer necessary, as a result of which, due to the shorter length of the blank, the friction between the blank and the forming tool to be overcome in the subsequent expansion of the blank by means of internal high pressure is considerably reduced.
In einer bevorzugten Ausführungsform der Erfindung gemäß Anspruch 2 erfolgt der Beschnitt der Enden des Rohlings so, dass die Stirnflächen der Enden zur in Quetschrichtung liegenden quer zur Längsachse des Rohlings verlaufenden Mittenachse angeschrägt werden. Diese Beschnittform resultiert aus der zusätzlichen Erkenntnis, dass die durch das Quetschen in Abhängigkeit von der Quetschrichtung entstehenden Deformationen des Rohlings zu einer Schiefstellung des Roh endenquer- schnitts und damit der Stirnfläche zur besagten Achse führen, so dass die Rohrenden im Sinne der Erfindung in Gegenrichtung angeschrägt werden. Bei der erwähnten Schiefstellung des Querschnittes überragt in axialer Richtung ein oberer Um- fangsbereich des Rohrendes dessen unteren Umfangsbereich.In a preferred embodiment of the invention, the ends of the blank are trimmed in such a way that the end faces of the ends are beveled in relation to the central axis lying in the squeezing direction and extending transversely to the longitudinal axis of the blank. This trimming form results from the additional knowledge that the deformations of the blank which arise as a result of the squeezing as a function of the squeezing direction lead to an oblique position of the raw end cross section and thus the end face to the axis mentioned, so that the pipe ends are beveled in the opposite direction in the sense of the invention become. When the cross-section is skewed, an upper circumferential region of the pipe end projects beyond its lower circumferential region in the axial direction.
In einer weiteren bevorzugten Weiterbildung der Erfindung nach Anspruch 3 werden die Rohlingsenden derart beschnitten, dass deren Stirnflächen parallel zueinander angeordnet verbleiben. Im Falle, dass nach erfolgter Quetschung die Endbereiche des Hohlprofilrohlings höhenversetzt zueinander zu liegen kommen, ist die Stirnfläche des einen unbeschnittenen Endes nach oben gekippt, so dass der untere Umfangsbereich a- xial den oberen Umfangsbereich des Endes überragt, und die Stirnfläche des anderen unbeschnittenen Endes nach unten gekippt, wobei in axialer Richtung der obere Umfangsbereich des Endes den unteren Umfangsbereich überragt. Der Rohling kann daher vor dem Quetschvorgang an beiden Enden unter gleichem Winkel in- Gegenrichtung der Kippung beschnitten werden. Die daraus herrührende Gleichartigkeit des Beschnittes stellt dabei eine Arbeitserleichterung des Schneidverfahrens dar. Gleiches gilt im übrigen für einen Seitenversatz der Enden nach erfolgter Quetschung.In a further preferred development of the invention according to claim 3, the blank ends are trimmed such that their end faces remain arranged parallel to one another. In the event that the end areas of the hollow profile blank come to lie vertically offset from one another after the pinching has taken place, the end face of one uncut end is tilted upward, so that the lower circumferential area axially projects beyond the upper circumferential area of the end, and the end face of the other untrimmed end tilted downward, the upper peripheral region of the end projecting beyond the lower peripheral region in the axial direction. The blank can therefore before the crimping process at both ends under the same Angle cut in the opposite direction of the tilt. The resulting uniformity of the trimming makes the cutting process easier. The same also applies to a lateral offset of the ends after the pinching has taken place.
Eine besonders bevorzugte Ausführungsform der Erfindung stellt gemäß Anspruch 4 die spezielle Bestimmung des Anschrä- gungswinkels des Beschnittes dar, der in einem Bereich zwischen 6° und 10°, vorzugsweise 8°, liegt. Hierzu hat sich in Untersuchungen praktischer und theoretischer Art herausgestellt, dass die Verkippung der Stirnflächen, die durch die quetschende Deformation hervorgerufen wird, nahezu immer in diesem Winkelbereich liegt, so dass in Gegenrichtung ein e- benso großer Anschrägungswinkel der Stirnfläche des Endes beim Beschnitt vorgesehen werden muss.A particularly preferred embodiment of the invention is, according to claim 4, the special determination of the bevel angle of the bleed, which lies in a range between 6 ° and 10 °, preferably 8 °. For this purpose, it has been found in studies of a practical and theoretical nature that the tilt of the end faces, which is caused by the squeezing deformation, is almost always in this angular range, so that in the opposite direction an equally large bevel angle of the end face of the end is provided when trimming got to.
Nach einer weiteren bevorzugten Ausführungsform der Erfindung gemäß Anspruch 5 wird vor dem Beschneiden der Enden, die durch den späteren Quetschvorgang real auftretende Endendeformation in einer Computersimulation, insbesondere einer Fi- nite-Elemente-Simulation ermittelt und dann daraus zur Kompensation der Deformation präzise eine optimale Beschnei- dungskontur und einen optimalen Anschrägungswinkel des zu erfolgenden Beschnitts errechnet . Hierdurch kann mit relativ geringem Aufwand ohne Inanspruchnahme von vielzähligen, mühseligen, empirischen Untersuchungen der für jedes Bauteil und für jede Art der Quetschung geeignete Anschrägungswinkel und Beschneidungskontur individuell ermittelt werden.According to a further preferred embodiment of the invention according to claim 5, before the ends are trimmed, the end deformation actually occurring as a result of the later squeezing process is determined in a computer simulation, in particular a finite element simulation, and then an optimal snowmaking is used to compensate for the deformation - Contour contour and an optimal bevel angle of the trimming to be carried out. As a result, the bevel angle and circumference contour suitable for each component and for each type of crushing can be determined individually with relatively little effort and without the use of numerous, laborious, empirical studies.
Nach einer weiteren bevorzugten Ausführungsform der Erfindung erfolgt gemäß Anspruch 6 der Beschnitt der Enden zweidimensi- onal . Dabei wird zwar die exakte Raumkontur des Rohlingsendes nicht erfasst, jedoch ist ein derartiger Beschnitt besonders verfahrensökonomisch und schnell ausführbar.According to a further preferred embodiment of the invention, the ends are trimmed in two dimensions. The exact spatial contour of the blank end is indeed not recorded, however such trimming can be carried out quickly and particularly economically.
In einer besonders bevorzugten Ausführungsform der Erfindung gemäß Anspruch 7 erfolgt der Beschnitt der Enden in einem dreidimensionalen Konturenschnitt. Dies kann beispielsweise mittels eines Schneidlasers erfolgen und bietet den axial andockenden Axialstempel die denkbar beste Anbindungsflache, so dass eine optimale Abdichtung mittels der Stempel erreicht wird.In a particularly preferred embodiment of the invention, the ends are trimmed in a three-dimensional contour cut. This can be done, for example, by means of a cutting laser and offers the axially docking axial punch the best possible connection surface, so that an optimal seal is achieved by means of the punch.
Im Folgenden ist die Erfindung anhand eines in den Zeichnungen dargestellten Ausführungsbeispieles näher erläutert. Dabei zeigt:The invention is explained in more detail below on the basis of an exemplary embodiment shown in the drawings. It shows:
Fig. 1 in einem seitlichen Halbschnitt einen beidseitig erfindungsgemäß beschnittenen Hohlprofilrohling in einem geöffneten Umformwerkzeug,1 is a side half section of a hollow profile blank trimmed on both sides according to the invention in an open forming tool,
Fig. 2 in einem seitlichen Halbschnitt den Hohlprofilrohling aus Figur 1 nach erfolgtem Quetschvorgang bei geschlossenem Innenhochdruckumformwerkzeu .Fig. 2 in a side half-section of the hollow profile blank from Figure 1 after the squeezing process with closed internal high pressure forming tool.
In Figur 1 ist ein Innenhochdruckumformwerkzeug 1 dargestellt, welches aus einem Oberteil 2 und einem Unterteil 3 besteht. Die Werkzeuggravur 4, die von beiden Werkzeugteilen 2 und 3 gebildet wird und einen Formraum für einen in das Werkzeug 1 eingelegten und umzuformenden Hohlprofilrohling 5 begrenzt, ist derart gestaltet, dass ein Ende 6 der Gravur 4 zum anderen Ende 7 höhenversetzt angeordnet ist . Diese beiden Enden 6 und 7 der Gravur 4 weisen im geschlossenen Umform- werkzeug 1 gemäß Figur 2 in etwa den gleichen Durchmesser auf wie der eingelegte Hohlprofilrohling 5. In einem Mittenbereich 8, der die beiden Enden 6 und 7 miteinander verbindet, ist die Gravur 4 erheblich querschnittsverengt. Der Hohlprofilrohling 5 weist seinerseits an seinen beiden Enden 9 und 10 eine in Richtung der Längsachse 11 des Hohlprofilrohlings 5 geneigte Stirnfläche 12 bzw. 13 auf. Während ein oberer Umfangsbereich der Stirnfläche 12 deren unteren Umfangsbereich 15 in axialer Richtung überragt, überragt ein unterer Umfangsbereich der Stirnfläche 13 deren oberen Um- fangsbereich 17 in axialer Richtung. Der Hohlprofilrohling 5, bei dem die Stirnflächen 12 und 13 seiner Enden 9 und 10 parallel zueinander angeordnet sind, befindet sich vollständig innerhalb der Gravur 4 des Umformwerkzeuges 1. Der Anschrägungswinkel der Stirnfläche 12 bzw. 13 zur Mittenhochachse 18 beträgt 8° .In Figure 1, an internal high pressure forming tool 1 is shown, which consists of an upper part 2 and a lower part 3. The tool engraving 4, which is formed by both tool parts 2 and 3 and delimits a molding space for a hollow profile blank 5 inserted and to be formed in the tool 1, is designed such that one end 6 of the engraving 4 is arranged offset in height from the other end 7. These two ends 6 and 7 of the engraving 4 have approximately the same diameter in the closed forming tool 1 according to FIG. 2 as the inserted hollow profile blank 5. The engraving 4 is in a central region 8 which connects the two ends 6 and 7 to one another significantly reduced in cross-section. The hollow profile blank 5 in turn has at its two ends 9 and 10 an end face 12 and 13 inclined in the direction of the longitudinal axis 11 of the hollow profile blank 5. While an upper circumferential area of the end face 12 projects beyond its lower circumferential area 15 in the axial direction, a lower circumferential area of the end face 13 projects beyond its upper circumferential area 17 in the axial direction. The hollow profile blank 5, in which the end faces 12 and 13 of its ends 9 and 10 are arranged parallel to one another, is located entirely within the engraving 4 of the forming tool 1. The taper angle of the end face 12 or 13 to the central vertical axis 18 is 8 °.
Zur Herstellung des Hohlprofils werden zuerst die Enden 9 und 10 des Rohlings 5 so beschnitten, dass sich angeschrägte Stirnflächen 12 und 13 ergeben, wobei diese möglichst zur in Quetschrichtung liegenden Achse angeschrägt sein sollen, um ein optimales Deformationsergebnis, das aus dem Quetschvorgang hervorgeht, zu erhalten und um damit ein sauberes Abdichten der später zur Innenhochdruckumformung andockenden A- xialstempel zu sichern. In diesem Ausführungsbeispiel erfolgt der Beschnitt der Rohlingsenden 9 und 10 derart, dass deren Stirnflächen 12 und 13 parallel zueinander verbleiben. Um den gewünschten Beschnitt zu ermöglichen, wird vor dem Beschnei- dungsvorgang die durch den späteren Quetschvorgang hervorgerufene Deformation der Enden 9 und 10 in einer Finite- Elemente-Computersimulation ermittelt und dann daraus die geeignete Beschneidungskontur und der geeignete Anschrägungswinkel errechnet. Der so beschnittene Hohlprofilrohling 5 wird nun 'in die Gravur 4 des Umformwerkzeuges 1 eingelegt, wonach dieses geschlossen wird. Aufgrund des die Gravur 4 verengenden Mittenbereichs 8 erfolgt im Schließvorgang des Umformwerkzeuges 1 durch das Aufeinanderzufahren des Ober- teils 2 und des Unterteils 3 eine Quetschung des Hohlprofil- rohlings 5. Die mittige Quetschung 19, die aus Figur 2 zu erkennen ist, welche das Umformwerkzeug 1 in seinem geschlossenen Zustand darstellt, wirkt sich auf die Enden 9 und 10 des Hohlprofilrohlings 5 derart aus, dass die Stirnflächen 12 und 13 des Rohlings 5 senkrecht zu seiner Längserstreckung stehen. Alsdann werden die Axialstempel an die Enden 9 und 10 des Hohlprofilrohlings 5 herangefahren und dichten diesen mit einem konischen Dichtbereich ab. Über die Axialstempel wird nun in den Hohlprofilrohling 5 ein Druckfluid eingeleitet und unter Hochdruck gesetzt. Aufgrund des bestehenden Innenhochdruckes wird der Hohlprofilrohling 5 aufgeweitet, wobei er sich vollständig an der Gravur 4 des Umformwerkzeuges 1 anlegt . Das Druckfluid wird nun entspannt und aus dem nun fertiggeformten Hohlprofil herausgeleitet, wonach die Axialstempel von dem Umformwerkzeug 1 zurückgefahren werden. Schließlich wird dieses geöffnet und das Hohlprofil aus der Gravur 4 entnommen.To produce the hollow profile, the ends 9 and 10 of the blank 5 are first trimmed in such a way that beveled end faces 12 and 13 result, these should be beveled as far as possible to the axis lying in the squeezing direction in order to obtain an optimal deformation result which results from the squeezing process and to ensure a clean seal of the axial ram that will later dock for internal high pressure forming. In this exemplary embodiment, the blank ends 9 and 10 are trimmed in such a way that their end faces 12 and 13 remain parallel to one another. In order to enable the desired trimming, the deformation of the ends 9 and 10 caused by the later squeezing process is determined in a finite element computer simulation and then the suitable trimming contour and the suitable bevel angle are calculated from this. The so truncated hollow profile blank 5 is now inserted 'into the impression 4 of the forming die 1, after which this is closed. Due to the central region 8 constricting the engraving 4, in the closing process of the forming tool 1, the upper partly 2 and the lower part 3 a pinch of the hollow profile blank 5. The central pinch 19, which can be seen from FIG. 2, which shows the forming tool 1 in its closed state, has an effect on the ends 9 and 10 of the hollow profile blank 5 in this way that the end faces 12 and 13 of the blank 5 are perpendicular to its longitudinal extent. The axial punches are then moved up to the ends 9 and 10 of the hollow profile blank 5 and seal them with a conical sealing area. A pressure fluid is now introduced into the hollow profile blank 5 via the axial rams and placed under high pressure. Due to the existing internal high pressure, the hollow profile blank 5 is widened, whereby it lies completely against the engraving 4 of the forming tool 1. The pressure fluid is now released and led out of the now fully formed hollow profile, after which the axial rams are moved back by the forming tool 1. Finally, this is opened and the hollow profile is removed from the engraving 4.
Im Übrigen sei an dieser Stelle betont, dass während der In- nenhochdruckumformung mittels der Axialstempel Rohlingsmaterial axial nachgeschoben werden kann. Die Erfindung bringt hierfür den bedeutenden Vorteil, dass durch die Geradestellung der Stirnflächen 12,13 eine homogene Krafteinleitung der Axialstempel in den auszubauchenden Umformbereich des Innen- hochdruckumformprozesses ermöglicht wird, was infolge der darauf beruhenden Vermeidung von unerwünschten Faltenbildungen und Materialverdickungen außerordentlich zur Prozesssicherheit des Umformprozesses beiträgt. It should also be emphasized at this point that blank material can be axially pushed in during the internal high pressure forming by means of the axial stamp. For this purpose, the invention has the significant advantage that the straight position of the end faces 12, 13 enables a homogeneous force introduction of the axial punches into the forming area of the internal high-pressure forming process that is to be bulged out, which contributes extraordinarily to the process reliability of the forming process due to the avoidance of undesired wrinkle formation and material thickening based thereon ,

Claims

Patentansprüche claims
Verfahren zur Herstellung eines umfänglich geschlossenen Hohlprofils mittels Innenhochdruckumformen, wobei ein hohler länglicher Rohling in ein Innenhochdruckumformwerkzeug eingelegt wird, wobei im Schließvorgang des Umformwerkzeuges der nach dem Einlegen vollständig innerhalb des Umformwerkzeuges befindliche Rohling in einem zwischen seinen Enden liegenden Bereich gequetscht wird, wonach der gequetschte Rohling mittels fluidischen Innenhochdruckes in die Endform des Hohlprofils aufgeweitet wird, d a d u r c h g e k e n n z e i c h n e t , dass die Enden (9,10) des Rohlings (5) vor dem Quetschvorgang unter Bildung jeweils einer angeschrägten Stirnfläche (12,13) beschnitten werden, und dass die Beschnittkontur der Enden (9,10) und der Anschrägungswinkel (α) derart gewählt werden, dass die Enden (9,10) mittels des Quetschvorganges so deformiert werden, dass deren Stirnflächen (12,13) eine im wesentlichen ebene Form aufweisen und eine Lage einnehmen, die weitestgehend senkrecht zur Längserstreckung des Rohlings (5) ist. Method for producing a circumferentially closed hollow profile by means of internal high-pressure forming, a hollow, elongated blank being inserted into an internal high-pressure forming tool, the blank being completely inside the forming tool after being inserted being squeezed in an area lying between its ends in the closing process of the forming tool, after which the squeezed blank is expanded into the final shape of the hollow profile by means of high fluidic pressure, characterized in that the ends (9, 10) of the blank (5) are trimmed prior to the squeezing process to form a beveled end face (12, 13), and that the trimming contour of the ends ( 9, 10) and the bevel angle (α) are selected in such a way that the ends (9, 10) are deformed by means of the squeezing process in such a way that their end faces (12, 13) have a substantially flat shape and assume a position that is as far as possible perpendicular to the longitudinal extension g of the blank (5).
2. Verfahren nach Anspruch 1, d a d u r c h g e k e n n z e i c h n e t , dass der Beschnitt so erfolgt, dass die Stirnflächen (12,13) der Enden (9,10) zur in Quetschrichtung liegenden quer zur Längsachse (11) des Rohlings (5) verlaufenden Mittenachse (18) angeschrägt werden.2. The method according to claim 1, characterized in that the trimming takes place in such a way that the end faces (12, 13) of the ends (9, 10) to the central axis (18) running in the squeezing direction and transverse to the longitudinal axis (11) of the blank (5). beveled.
3. Verfahren nach einem der Ansprüche 1 oder 2 , d a d u r c h g e k e n n z e i c h n e t , dass die Rohlingsenden (9,10) derart beschnitten werden, dass deren Stirnflächen (12,13) parallel zueinander angeordnet verbleiben.3. The method as claimed in claim 1, wherein the blank ends (9, 10) are trimmed in such a way that their end faces (12, 13) remain arranged parallel to one another.
4. Verfahren nach einem der Ansprüche 1 bis 3, d a d u r c h g e k e n n z e i c h n e t , dass der Anschrägungswinkel (α) in einem Bereich zwischen 6 und 10°, vorzugsweise 8° liegt.4. The method according to any one of claims 1 to 3, so that the bevel angle (α) is in a range between 6 and 10 °, preferably 8 °.
5. Verfahren nach einem der Ansprüche 1 bis 4, d a d u r c h g e k e n n z e i c h n e t , dass vor dem Beschneiden der Enden (9,10) die durch den späteren Quetschvorgang auftretende Endendeformation in einer Computersimulation ermittelt und dann daraus zur Kompensation der Deformation eine Beschneidungskontur und ein Anschrägungswinkel (α) des zu erfolgenden Beschnitts errechnet wird.5. The method according to any one of claims 1 to 4, characterized in that prior to the trimming of the ends (9, 10), the end deformation occurring due to the later squeezing process is determined in a computer simulation and then a compensation contour and a bevel angle (α) to compensate for the deformation. of the trimming to be performed.
6. Verfahren nach einem der Ansprüche 1 bis 5, d a d u r c h g e k e n n z e i c h n e t , dass der Beschnitt der Enden (9,10) zweidimensional erfolgt . Verfahren nach einem der Ansprüche 1 bis 5, d a d u r c h g e k e n n z e i c h n e t , dass der Beschnitt der Enden (9,10) in einem dreidimensionalen Konturenschnitt erfolgt. 6. The method according to any one of claims 1 to 5, characterized in that the trimming of the ends (9, 10) is carried out two-dimensionally. Method according to one of claims 1 to 5, characterized in that the ends (9, 10) are trimmed in a three-dimensional contour cut.
EP04729065A 2003-05-24 2004-04-23 Method for producing a peripherally closed hollow profiled element Expired - Lifetime EP1628788B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE10323738A DE10323738B3 (en) 2003-05-24 2003-05-24 Manufacturing closed hollow profile involves cutting semi-finished product ends to form angled ends before squeezing; contour, angle are selected so ends form essentially flat shape after squeezing
PCT/EP2004/004301 WO2004103602A1 (en) 2003-05-24 2004-04-23 Method for producing a peripherally closed hollow profiled element

Publications (2)

Publication Number Publication Date
EP1628788A1 true EP1628788A1 (en) 2006-03-01
EP1628788B1 EP1628788B1 (en) 2007-05-30

Family

ID=33305223

Family Applications (1)

Application Number Title Priority Date Filing Date
EP04729065A Expired - Lifetime EP1628788B1 (en) 2003-05-24 2004-04-23 Method for producing a peripherally closed hollow profiled element

Country Status (6)

Country Link
US (1) US20060248933A1 (en)
EP (1) EP1628788B1 (en)
JP (1) JP2006528075A (en)
CA (1) CA2526774A1 (en)
DE (3) DE10323738B3 (en)
WO (1) WO2004103602A1 (en)

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
TW201114521A (en) * 2009-10-29 2011-05-01 Metal Ind Res & Dev Ct Method of forming and manufacturing U-shaped metal tube support frame
CN114653806B (en) * 2022-03-01 2023-12-22 哈尔滨工业大学（威海） Preforming method for high-strength steel reducing tubular part

Family Cites Families (13)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE645954A (en) * 1963-03-28
USRE33990E (en) * 1987-05-06 1992-07-14 Ti Corporate Services Limited Method of forming box-like frame members
DE4320237C1 (en) * 1993-06-18 1994-08-18 Schaefer Maschbau Wilhelm Method and device for producing a hollow item according to the internal high-pressure process
US5644829A (en) * 1993-08-16 1997-07-08 T I Corporate Services Limited Method for expansion forming of tubing
JP3509217B2 (en) * 1994-09-20 2004-03-22 株式会社日立製作所 Forming method and forming apparatus for deformed cross-section pipe
US5557961A (en) * 1995-11-13 1996-09-24 General Motors Corporation Hydroformed structural member with varied wall thickness
AU2170297A (en) * 1997-03-27 1998-10-22 Ti Corporate Services Limited Method and apparatus for forming of tubing
US6016603A (en) * 1997-05-12 2000-01-25 Dana Corporation Method of hydroforming a vehicle frame component
CA2296098C (en) * 1997-07-18 2007-01-30 Cosma International Inc. Hydroforming of a tubular blank having an oval cross section and hydroforming apparatus
DE19813012C2 (en) * 1998-03-25 2002-08-01 Daimler Chrysler Ag Process for producing a hollow body from a tubular blank by hydroforming
US6065502A (en) * 1998-10-07 2000-05-23 Cosma International Inc. Method and apparatus for wrinkle-free hydroforming of angled tubular parts
JP3854812B2 (en) * 2001-03-27 2006-12-06 新日本製鐵株式会社 Strength members for automobiles
EP1389497A4 (en) * 2001-05-22 2009-04-29 Mitsubishi Motors Corp Hydroform process, and hydroform product formed by the process

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO2004103602A1 *

Also Published As

Publication number Publication date
DE502004003973D1 (en) 2007-07-12
WO2004103602A1 (en) 2004-12-02
US20060248933A1 (en) 2006-11-09
EP1628788B1 (en) 2007-05-30
DE112004000725D2 (en) 2006-10-19
DE10323738B3 (en) 2004-11-18
JP2006528075A (en) 2006-12-14
CA2526774A1 (en) 2004-12-02

Similar Documents

Publication Publication Date Title
DE4322063C2 (en) Method and device for cutting out a section of a wall of a hollow body produced by the hydroforming process
DE69317303T3 (en) SELF-PUNCHED RIVETS
EP2303488B1 (en) Method and device for producing fine-blanked parts from a material strip
DE2747382C2 (en) Method for producing a flange piece having a hollow cylindrical part and device for carrying out the method
DE2610568C3 (en) Method and device for producing crank strokes
EP1986801B1 (en) Method and device for producing a cutout or aperture in the wall of a component formed according to the hydroforming process
DE60030693T2 (en) COMPRESSIVE INNER HIGH PRESSURE FORMING
DE19647963C2 (en) Method and device for producing holes on the circumference of hollow profiles
DE69913646T2 (en) Device for high pressure molding and high pressure cutting
DE10328452B3 (en) Production of a hole on the outer periphery of a closed hollow profile having high inner pressure comprises moving a stamp in a guiding hole of a deforming tool with a drive part and subjecting the stamp to drive contours of the drive part
DE102009048040A1 (en) Method and device for chipless production of an external thread on hollow metal workpieces
EP2263812A1 (en) Method for producing stamped parts, in particular synchronous rings, coupling bodies or coupling discs
DE19839526C1 (en) Method of pressing metal component from sheet blank
DE2165247A1 (en) DEVICE AND METHOD FOR SEPARATING TUBULAR BLANKS
DE102006053223B3 (en) Sheet metal punch has centering tip surrounded by circular shoulder in close proximity to surplus metal ejector pins
DE10048005B4 (en) Device for connecting at least two flat, superimposed components
EP1628788B1 (en) Method for producing a peripherally closed hollow profiled element
DE19935714B4 (en) Device and method for separating or punching a workpiece
EP1741497B1 (en) Method and tool for producing without cutting a notch in a workpiece and workpiece with such notch
DE4444857C1 (en) Method for forming opening in wall of esp. exhaust pipe
DE69419206T2 (en) Method and device for manufacturing a metallic part
DE3816090C2 (en)
DE10309381A1 (en) Connecting workpieces within an adding range, by pushing a portion of one workpiece through a stamp towards the other workpiece such that the connecting pin of that workpiece is inserted into the opening of the other workpiece
DE2736625C2 (en)
DE69202427T2 (en) Method for producing an axis with profiled ends, machine for carrying out the method and axis produced with it.

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

17P Request for examination filed

Effective date: 20051129

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE ES FR GB IT SE

DAX Request for extension of the european patent (deleted)
RBV Designated contracting states (corrected)

Designated state(s): DE ES FR GB IT SE

GRAP Despatch of communication of intention to grant a patent

Free format text: ORIGINAL CODE: EPIDOSNIGR1

GRAS Grant fee paid

Free format text: ORIGINAL CODE: EPIDOSNIGR3

RAP1 Party data changed (applicant data changed or rights of an application transferred)

Owner name: DAIMLERCHRYSLER AG

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE ES FR GB IT SE

REG Reference to a national code

Ref country code: GB

Ref legal event code: FG4D

Free format text: NOT ENGLISH

REF Corresponds to:

Ref document number: 502004003973

Country of ref document: DE

Date of ref document: 20070712

Kind code of ref document: P

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: SE

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20070830

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: ES

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20070910

RAP2 Party data changed (patent owner data changed or rights of a patent transferred)

Owner name: DAIMLER AG

GBV Gb: ep patent (uk) treated as always having been void in accordance with gb section 77(7)/1977 [no translation filed]

Effective date: 20070530

PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20070530

Ref country code: IT

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20070530

26N No opposition filed

Effective date: 20080303

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Free format text: LAPSE BECAUSE OF FAILURE TO SUBMIT A TRANSLATION OF THE DESCRIPTION OR TO PAY THE FEE WITHIN THE PRESCRIBED TIME-LIMIT

Effective date: 20080125

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 20101012

Year of fee payment: 7

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20111101

REG Reference to a national code

Ref country code: DE

Ref legal event code: R119

Ref document number: 502004003973

Country of ref document: DE

Effective date: 20111101