EP2571635A1

EP2571635A1 - Method for producing a hollow profiled section

Info

Publication number: EP2571635A1
Application number: EP11716273A
Authority: EP
Inventors: Thomas Flehmig
Original assignee: ThyssenKrupp Steel Europe AG
Current assignee: ThyssenKrupp Steel Europe AG
Priority date: 2010-05-19
Filing date: 2011-04-27
Publication date: 2013-03-27
Also published as: US9272318B2; US20130104368A1; CN102933328B; DE102010017022A1; JP5913294B2; DE102010017022B4; JP2013526411A; WO2011144427A1; CN102933328A

Abstract

The invention relates to the problem of providing a method by which substantially crack and/or fold-free hollow profiled sections having greater curvature can be produced, which is solved according to the invention by a method for producing a hollow profiled section having a curvature section with a curvature center (7 ', 107a ', 107b '), wherein a blank (1, 101) is preformed into a U-profile (1 ', 101 ') by advancing a plunger into a first die, and the U-profile (1 ', 101 ') is formed by a second die into an O-profile (1 ' ' ', 101 ' ' ') having at least one longitudinal slot, wherein the blank (1, 101) is preformed into a U-profile (1 ', 101 '), the outer limb (8 ', 108a', 108b') of which, which is associated with the curvature section and faces away from the curvature center (7 ', 107a ', 107b '), is higher (H₁, H₁ ') at least in some regions than the inner limb (9 ', 109a ', 109b', H₂, H₂'), which is associated with the curvature section and faces the curvature center (7 ', 107a ', 107b ').

Description

Method for producing a hollow profile

The present invention relates to a method for

Producing a hollow profile having a curvature center having a curvature section, wherein a board is preformed by retracting a punch in a first die to a U-profile and the U-profile is formed with a second die to an O-profile with at least one longitudinal slot. Likewise, the invention is concerned with a support core for carrying out the method. Finally, a hollow profile with a curvature center

comprising curving section of the invention.

A method for producing a hollow profile with a curved portion is, for example, in the

DE 10 2004 025 857 AI described. In the known

Method is first provided a planar board having a first elongated area, one on it

subsequent transition area and one at this

having subsequent second elongated area. A first longitudinal center line of the first region extends at an angle relative to a second longitudinal center line of the second elongated region. The material blank is then preformed along the first region, the transition region and the second region to form a U-profile which extends at an angle rounded in the longitudinal direction and has legs of substantially equal length. Subsequently, the U-profile is further formed into an O-profile and the adjacent, centrally located at the highest point edges of the O-profile are welded together. It has been shown that cracks or wrinkles can occur in the production of in particular more highly curved hollow bodies with the known method in the curved section.

On this basis, the invention is therefore based on the object, a method with the substantially crack and / or wrinkle-free hollow profiles stronger curvature

can be produced, and to provide a corresponding hollow profile. Likewise, a support core is to be provided for carrying out the method.

After a first lesson, this task is through

A method for producing a hollow profile with a curvature center having a curved portion solved in which a board is preformed by retracting a punch in a first die to a Ü-profile and the U-profile with a second die to an O-profile with

is formed at least one longitudinal slot, wherein the board is preformed into a U-profile, of which

Curvature center averted, the curvature section

associated outer leg is at least partially higher than the curvature center facing, the

Curved portion associated inner leg. With the at least partially or partially higher outer leg more material is made available there, where the ü-profile is subjected to higher strains when forming an O-profile with longitudinal slot. The risk of expansion cracks in these areas with more curved hollow bodies can thus be reduced. In addition, it allows this

Approach to avoid the use of special optimized materials with regard to their expansion behavior. It can be chosen as a material for the hollow body thus particularly cost-effective, lightweight or high-strength materials. According to a first embodiment of the method, by preforming the board into a U-profile and / or shaping the U-profile into an O-profile with a longitudinal slot, an area of the board assigned in the outer leg becomes

provided recess narrows to a miter slot. In this way, a wave or wrinkling in

External legs are counteracted by compressive stresses.

Another development of the method provides to form the U-profile to an O-profile with at least one longitudinal slot and a miter slot, which communicate with each other. This will be stronger on the one hand

Allows radii of curvature. Communicating with each other

standing longitudinal and miter slots can

integral connection of the edges beyond

simplify, because the opposite edges can be brought into the welding position with lower stresses in the hollow profile. As a result, the edges of the component to be produced can simply be brought to impact and welded. In a further embodiment, the longitudinal slot

and / or the miter slot of the O-profile

cohesive bonding, in particular gluing, soldering, welding, the edges to a longitudinal seam and / or a

Mitred seam closed. By closing the slots, the resistance of the hollow profile can be further increased under load. Hollow profiles with such a closed cross section, in particular for the production of the Occupant protection components of motor vehicles are used.

Furthermore, the method can be further developed by introducing a support core, in particular an articulated support core, into the U-profile, in particular laterally, before shaping the U-profile into an O-profile with a longitudinal slot. With the support core can be a buckling of the

Outer leg and / or inner leg when forming the U-profile to prevent an O-profile with longitudinal slot. In addition, the dimensional accuracy of the produced hollow profile

be improved. An articulated support core can be removed non-destructively after forming into an O-profile with a longitudinal slot and therefore used several times.

A next embodiment provides to use a support core with at least one mold element and extend the mold element before or after the introduction of the support core in the ü-profile. The form element can serve thereby,

Support undercuts during the molding of the U-profile to an O-profile from the inside. An extension of the

Formula elements only after the introduction of the support core allows a more flexible choice of the direction of insertion of the support core in the U-profile. For example, the support core can also be introduced from one direction into the U-profile, whose cross-section does not allow insertion with extended form element. On the other hand, at one already before the

Inserting the support core extended in the U-profile

Form element whose exact position is better controlled. In a further embodiment, the support core before or after the closing of the slot of the O-profile

cohesive connection of the edges of the O-profile pulled. Pulling before joining can remove the

Simplify support core. For example, the risk of accidental cohesive connection of the support core is reduced with the O-profile. On the other hand, a pulling of the support core allows a higher dimensional accuracy of the hollow profile to be produced.

In a next development, the hollow profile is produced from a board designed as a "tailored blank" or as a "patchwork blank". "Tailored blanks" refers to blanks that are assembled from individual sheets of different thickness, strength and / or surface coating. This makes it possible to use a thicker and / or higher-strength material on the one hand in places with higher load. On the other hand, can be used at the remaining locations on thinner or softer sheets. Tailored blanks thus enable weight reduction. In addition, they allow high-quality and expensive materials to be used only in the really necessary places, so that

Cost savings can be achieved. In patchwork blanks, motherboards are strengthened locally by attaching individual additional reinforcement plates. Motherboard and reinforcing plates can be easily shaped together afterwards. The laborious and costly

Attachment of reinforcements on the later component can thus be omitted. As motherboards for patchwork blanks in particular also tailored blanks come into question, with the reinforcing plates for a small-scale local

Reinforcements can be made, so for the Single sheets of Tallored Blanks a further reduced thickness or other material can be selected.

Of course, the board can also be monolithic or "Tailored Roiled Blank" be formed, that is, consist of a single material and have different material thicknesses in the case of "Tailored Roiled Blank".

Preferably, steels / steel alloys are used.

Furthermore, in one embodiment of the method

flanged or a flangeless hollow profile

produced. At the flanges flange-shaped hollow profiles, these can be easily connected to other components material and / or positive fit. Especially

Adhesive connections can be made by providing a

sufficient adhesive surface on the flange are made possible. On the other hand, weight can be saved with flangeless hollow sections. Flange-affixed or flangeless hollow profiles can, for example, also be reliably connected to other components by laser welding.

Finally, a Heiterbildung the method that the board during the preforming to a Ü-profile and / or during the molding of the U-profile trimmed and / or perforated to an O-profile with at least one longitudinal slot. A trimming or perforation of the hollow profile can

for example, if required, for example

additional elements, such as cables to be laid through the hollow section. By integrating the punching and / or trimming into the preforming or forming process, the number of working steps required to produce a hollow profile can be further reduced. A reduction the steps allow shorter cycle times and thus a cheaper production of hollow sections.

According to a second teaching, the above-mentioned object is achieved by a support core which has at least one core element with at least one extendable molding element.

In a first embodiment, the support core has at least two core elements. An at least two-part support core also allows complicated, for example

nodular, hollow profiles during the molding of a U-profile to an O-profile with longitudinal slot from the inside

support and can still be pulled after forming the O-profile or after closing the longitudinal slot in a simple manner.

According to another teaching of the invention, the above

said object solved by a hollow profile, which has a first longitudinal slot or a first longitudinal seam and the first longitudinal slot or the first longitudinal seam in

Curved portion eccentrically displaced toward the center of curvature extends. The displaced longitudinal seam causes a reduction of remaining in the hollow profile

Expansion stresses.

In a first embodiment, the hollow profile has a further longitudinal slot or a further longitudinal seam and / or a miter slot or a miter seam, and the further longitudinal slot or the further longitudinal seam and / or the miter slot or the miter seam are connected to the first

Longitudinal slot or the first longitudinal seam connected. Such Hollow profile after the manufacturing process can be produced particularly cost.

According to a next development, the hollow profile is made of a monolithic board, a tailored blank or a patchwork blank. With regard to it

Connected advantages will be on the designs for

directed to the inventive method. Furthermore, an embodiment provides that the hollow profile has at least one inner undercut.

Internal undercut allow, for example, a stiffening of the hollow profile in this area. Likewise, inner undercuts for receiving a connecting element, such as a screw head serve.

Finally, the hollow profile can be further developed in that it is designed as a node, in particular as a T-piece. As a node in the context of the invention of several tubular sections composite hollow profiles

designated, wherein the tubular portions are connected to each other so that they form a coherent interior. In the simplest case, a further tube-like branch branches vertically from an elongated tube-like section

Section off, so that a hollow profile is formed in the form of a tee. Among nodes, however, inter alia, cross or Y-shaped hollow sections understood. With the help of nodes, structures,

For example, for motor vehicle bodies, are formed, which are characterized by a low weight. In addition, the invention will be explained in more detail with reference to a drawing in conjunction with exemplary embodiments. The drawing shows in: FIG. 1 a first board for the production of a

Hollow section; the first board formed into a first U-profile shown in FIG. 1; a first, made of the U-profile shown in Figure 2 embodiment of a hollow profile according to the invention; a suitable for producing the hollow profile support core; a second board for producing a hollow profile; the second board formed into a second U-profile shown in FIG. 5; a core suitable for producing the second hollow profile shown in FIG. 6 in the removal state;

FIG. 8 shows the core shown in FIG. 7 in the deformed state; FIG.

9 shows a second embodiment of a hollow profile according to the invention made from the U-profile shown in FIG. 6. The in Fig. 1 in a perspective view

illustrated board 1 has a first substantially rectangular area 2, an adjoining

Transition region 3 and a subsequent to this second second substantially rectangular area 4. The edges 5 and 6 form after forming the lateral end of the hollow profile to be produced. In the transition region of the board 1, a recess 7 is provided. At the shown board

1 is a tailored blank.

In a first method step, the circuit board 1 is moved by retracting a punch, not shown, in a likewise not shown first die to that in FIG. 2

shown Ü-profile 1 'preformed. The U-profile has a first substantially rectangular area

2 corresponding longitudinal portion 2 'and a second substantially rectangular portion 4 corresponding longitudinal portion 4' on. The transition region 3 is to a curvature section 3 'with a curvature center 7'

preformed. The the curvature center 7 'facing away

Outer leg 8 'is at least partially higher (Hi) than the curvature center facing inner leg 9' (H ₂ ).

In the U-profile of the articulated support core 10 '' shown in FIG. 3 in a direction parallel to the

Outer leg 8 'and the inner leg 9' introduced into the U-profile 1 '. During the subsequent shaping of the U-profile 1 'in the illustrated in Fig. 4 O-profile I ^» ·· with the aid of a second die, not shown, the support core 10' · supports the U-profile 1 'from the inside, so that a buckle

for example, the outer leg 8 'or the inner leg 9' can be avoided. The in the collapsed state rigidly connected members 11 '' of the support core 10 '' can be in the longitudinal extension of the support core 10 ''

pull apart and are then relative to each other

bendable. The support core can thus be pulled laterally out of the O-profile l ' ¹ ' after the U-profile 1 'has been formed into an O-profile 1'"with a longitudinal slot, in the course of forming the blank 1 into an Ü-profile 1 '. and further to a 0-profile, the recess 7 becomes a miter slot

narrows. This and the longitudinal slot are subsequently by laser welding of the formed I-joint to a miter seam 13 '' 'and a longitudinal seam connected thereto

12 '' 'closed. It is also conceivable to pull the support core 10 "out of the O-profile 1 '' 'only after the cohesive closing of the longitudinal and / or miter slot.

In the region of the lateral end regions of the O-profile 1 '' 'there are no compressions or strains, since they can be unwound to the corresponding areas 2 and 4 of the board. If a larger area for connecting the

shown O-profile 1 '' 'is desired with other components, can be with the method according to the invention instead of the flangeless front areas also shown

manufacture, which have a flange. Furthermore, in the case of more complex components, a plurality of recesses may be provided, which are narrowed to form a plurality of miter slots during the molding of a component and to a plurality by means of welding

Miter seams are closed.

Fig. 5 shows a further board 101 for producing a hollow profile with two curvature sections. The circuit board 101 is intended to be formed into a T-shaped hollow profile. It basically has a first one rectangular region 103a, an adjoining transition region 104 and an adjoining second substantially rectangular region 103b.

In addition, a third is substantially rectangular

Area 105 is provided, which laterally in contact with the

Passage area 104 is.

The circuit board 101 is initially in a not shown

Device arranged between a punch and a first die and preformed by moving together of the punch and the first die to the U-profile 101 'shown in FIG. The U-profile 101 'has a T-shaped configuration, wherein the vertical section 105' of the T is formed by the third substantially rectangular region 105. The vertical section 105 'then goes over two of the

Transition areas formed curved portions 104a ', 104b', each associated with a center of curvature 107a ', 107b', in the formed from the first and second substantially rectangular portion 103a, 103b of the board 101 horizontal portion 103 'of the T over. The outer leg 108a ', 108b' of the U-profile 101 'facing away from the respective center of curvature 107a', 107b 'is present here

Embodiment consistently higher (Ηχ ') than that of the respective curvature center 107a', 107b 'facing

Inner legs 109a ', 109b' (IV). It is also conceivable, however, that the outer leg facing away from the center of curvature is only partially or partially higher than the latter

Curvature center facing inner leg. The support core 110 "shown in FIGS. 7 and 8 is then inserted into the preformed U-profile 101 '. The support core 110 '' is composed of a first core element 114 '' and a second core element 115 ". Both the first

The core element 114 ' ¹ as well as the second core element 115 "each have swing-out shaped elements 116", 118 "or 117", 119 " first core element 114 "with retracted form elements 116", 118 "is pushed laterally in the direction of the horizontal section 103 'of T. Subsequently, the second core element 115" is likewise inserted with retracted form elements 117 ", 119" in FIG

Direction of the vertical portion 105 'of the T in the U-profile 101' inserted so that it flush with the first core element 114 "connects

Core elements 114 ", 115" are then the mold elements 116 ", 117", 118 ", 119", as shown in FIG. 8,

extended.

In the next step is not with a

illustrated second die the Ü profile 101 'to the O-profile shown in FIG. 9 101' "with a first

Longitudinal slot 112a '"and a second longitudinal slot 112b'" shaped, which communicate with each other and through

Laser welding to be closed. During the forming of the undercuts 120a '', 120b '' they are supported from the inside by the mold elements 116 ', 117 ", 118", 119 ". The undercuts 120a "', 120b'" support the

Connection area from the vertical portion 105 "'and horizontal portion 103"' of the T, so that too

Forces perpendicular to the vertical portion 105 '' of the O-profile 101 'can be safely introduced into the horizontal portion 103' '

Welding the edges, the mold elements 116 ", 117", 118 ", 119" retracted and the core elements 114 ", 115 '' pulled against the respective insertion direction of the hollow section 101 ''.

For the production of the hollow profiles 1 '", 101"' respectively shown in FIGS. 4 and 9, there is therefore only one force-intensive one for the actual Ü-O shaping processes

Direction of movement necessary. The method can therefore be carried out with standardized and therefore inexpensive available devices.

Claims

claims

Method for producing a hollow profile with a center of curvature (7 *, 107a ', 107b')

Curved portion in which a board (1, 101) is preformed by retracting a punch in a first die to a ü-profile (1 x, 101 ') and the ü-profile (Ι', 101 ') with a second die an O-profile (1 '", 101'") is formed with at least one longitudinal slot,

characterized in that the circuit board (1, 101) is preformed into a U-profile (1 x ', 101') whose outer leg (8 ', 108a') facing away from the center of curvature (7 ', 107a', 107b ') and assigned to the curved section , 108b ') is at least partially higher (Hi, Ηι') than the curvature center (7 ', 107a', 107b ') facing, the curved portion associated inner leg (9', 109a ', 109b', H ₂ , H ₂ ' ).

Method according to claim 1,

d a d u r c h e c e n e, e s by preforming the board into a U-profile and / or shaping the U-profile into an O-profile with a longitudinal slot associated with the outer leg! Area of the board provided recess to a

Miter slot is narrowed. Method according to one of claims 1 or 2,

That is, the U-profile is formed into an O-profile having at least one longitudinal slot and a miter slot communicating with each other.

Method according to one of claims 1 to 3,

characterized,

the longitudinal slot and / or the Gehrungsschlitz of 0- profile (1 "',^101') by integral joining, in particular gluing, soldering, welding, of the edges (in a longitudinal seam ^12,,,, 112a" ·, 112b '") and or

Miter seam (13 '' ') is closed.

Method according to one of claims 1 to 4,

characterized in that prior to forming the U-profile (1 ', 101') to an O-profile (1 · ", 101" ') with longitudinal slot a support core (10 ", 110' '), in particular an articulated support core (10 '·), In the U-profile (1', 101 ') introduced, in particular laterally inserted, is.

Method according to claim 5,

characterized in that a support core (110 '') is used with at least one mold element (116 ", 117", 118 ", 119") and the mold element (116 ", 117", 118 ", 119") before or after insertion is extended.

Method according to one of claims 5 or 6,

characterized in that the support core (10 ", 110") before or after closing of the slot of the O-profile (1 x, 101 "')

cohesively joining the edges of the O-profile (1 ', 101' '') is drawn, wherein in the use of a mold element (116 ", 117", 118 ", 119") having support core (110 ") this before drawing is retracted.

8. The method according to any one of claims 1 to 7,

That is, the hollow profile (1 '", 101'") is produced from a printed circuit board (1, 101) designed as a "tailored blank" or as a "patchwork blank".

9. The method according to any one of claims 1 to 8,

d a d u r c h g e k e n c i n e, that is, the flange-shaped hollow profile or a

flangeless hollow section (1 "', 101'") is produced.

10.A method according to one of claims 1 to 9,

characterized in that the blank (1, 101) during preforming to a U-profile (1 ', 101') and / or during closing to an O-profile (1 '", 101'") trimmed with longitudinal slot and / or being punched.

11.Stützkern for carrying out a method according to any one of claims 1 to 10,

characterized in that the support core (110 ") has at least one core element (114", 115 ") with at least one extendable mold element (116", 117 ", 118", 119 "). Support core according to claim 11,

In other words, the support core (110 ') has at least two core elements (114 ··, 115 ").

Hollow profile having a curved section, in particular produced by a method according to one of claims 1 to 10,

d a d u r c h e k e n e, that is, the hollow profile (1 · ", 101 '") has a first one

Longitudinal slot / a first longitudinal seam (12 "', 112a"',

112b '") and the first longitudinal slot / the first longitudinal seam (12", 112a' '', 112b '') in the curved portion is eccentrically displaced towards the center of curvature (7 ', 107a', 107b ').

Hollow profile according to claim 13,

characterized in that the hollow profile (1 ', 101 "') has a further longitudinal slot or a further longitudinal seam (112b '", 112a' ") and / or a miter slot or a miter seam (13" ') and the further longitudinal slot or the other Longitudinal seam (112b '", 112a'") and / or the Mithrschschiit or the miter seam (13 "') with the first Längsschiit or the first longitudinal seam (12", 112a "', 112b '") are connected. Hollow profile according to one of claims 13 or 14,

characterized in that the hollow profile (1 '") is made of a tailored blank (1) or a patchwork blank. Hollow profile according to one of claims 13 to 15,

That is, the hollow profile (101 '' ') has inner undercuts (120a' ', 120b' ''). Hollow profile according to one of claims 13 to 16,

The hollow profile (101 '' ') is in the form of a knot, in particular a T-piece, in that the hollow profile (101' '') is designed as a knot.