DE102014004157A1 - Process for the production of load introduction flanges on fiber-reinforced hollow profiles with thermoplastic matrix - Google Patents

Abstract

The invention relates to a method for producing load introduction flanges (3, 4) on fiber-reinforced hollow profiles (2) with a thermoplastic matrix, comprising at least the following steps: - heating (6) a hollow profile end section (5) of the fiber-reinforced hollow profile (2), - pressing (7) the heated hollow profile end section (5) onto a molding dome (8) of a tool (31), expansion of at least one hollow profile edge part (9) of the hollow profile end section (5) to form a flange structure (41) on the molding dome (8), - applying (27) additional material (11) compatible with the thermoplastic matrix of the hollow section (2) to the preformed flange structure (41) from a fixed circumference (12) on the hollow profile end section (5) in a closed manner Tool (31), - generating at least one cohesive connection between the matrix of the fiber-reinforced hollow profile (2) and the material (11) applied to the flange structure (41) for the formation of the final load introduction flange (3, 4) and - removal of the final load introduction flange (3, 4) from the tool (31). In this case, there is a load introduction flange (3, 4) on a fiber-reinforced hollow profile (2) with a thermoplastic matrix at least a Hohlprofilendabschnitt (5), an expanded hollow profile edge portion (9) of the Hohlprofilendabschnitts (5), a Anspritzteil / pressed part (11) from the hollow profile edge part (9) up to a predetermined peripheral region (12) of the Hohlprofilendabschnitts (5) is attached and at least partially overlaid the processed Hohlprofilendabschnitt (5), wherein at least one cohesive connection of the contact of the processed Hohlprofilendabschnitts (5) and the Anspritzteils / Pressed parts (11) is formed.

Description

The invention relates to a method for the production of load introduction flanges on fiber-reinforced hollow profiles with thermoplastic matrix and associated load introduction flanges.

The invention finds application in the functionalization of hollow profiles with mostly cylindrical cross section, which consist of a fiber composite material with a thermoplastic matrix. They are basically suitable for many technical applications in the form of machine components such as axles, shafts and pipelines. The underlying hollow profiles can be produced, for example, in the pultrusion process continuously and energy-efficiently with a predefined fiber orientation. They can be kept as standard semi-finished products and then individually cut to length according to the respective application. For the further technical use of such fiber-thermoplastic composite hollow sections, however, suitable load introduction systems are still required, which can be easily and inexpensively install at any arbitrary length of the semifinished product.

The inventive method describes the advantageous and novel design of an integral flange structure made of fiber-reinforced thermoplastic that meets these requirements.

The flange structure makes it possible to absorb and introduce axial loads, bending moments and in particular torsional moments into the load-transmitting fiber composite structure while largely dispensing with extraneous materials such as steel or titanium, as in 1 is shown.

In the prior art, many load introduction systems in fiber composite hollow structures are known, which are formed flange. Very often are the metallic flanges, which are mounted on different principles of largely cylindrical fiber composite hollow sections.

Furthermore, some integral fiber composite flanges are already known in which the fibers are deflected out of the pipe area and optionally reinforced by blanks or metal parts. However, according to the current state of knowledge, this has only been done for fiber composite structures with thermosetting resin systems such as epoxy, polyester or vinyl ester resins. In general, complicated preforming operations such as flange forming using thermosets are quite complex and limited automation. The use of standard semi-finished products of any length, which brings a significant cost advantage, is severely limited. In addition, the generally very brittle material behavior of thermosets prevents a load-bearing transition from continuous-fiber-reinforced to short-fiber-reinforced component regions, so that a final contour-identical primary shaping is very difficult to realize. This has further manufacturing steps and thus time and cost required.

After this general classification and evaluation, specific reference will be made below to known fiber composite structures, against which a distinction is made.

From the pamphlets DE 44 14 384 A1 and DE 199 06 618 A1 It is known to deposit a fiber reinforcement on largely cylindrical tool systems and then spread this fiber reinforcement at the ends and form a flange. Because of the resulting thinning of the material, it may be necessary, for. B. insert annular reinforcing layers. The handling of the dry fibers and the thickening is complex because they have no solid cohesion.

In numerous pamphlets CN 191677 C . DE 000002058015 A . DE 3608754 C2 . DE 4442268 C1 . US 2009/0308477 A1 . EP 0413677 A1 . WO 1998020263 A1 a flange is preformed in the fiber tray and then formed in subsequent steps. This usually happens with the attachment of additional reinforcement layers. Either this process takes place in the "wet" state (ie using already resin-impregnated fibers) or in the "dry" state, ie using dry fibers, which are impregnated with resin in a subsequent infiltration process. A fiber orientation which is advantageous for the initiation of torsional loads does not come about "by itself".

In the pamphlets DE 4014400 A1 . EP 0307112 B1 . US 5724715 A are described fiber reinforced flange components and methods for their preparation, which have a relatively favorable fiber angle course (in terms of the initiation of torsional). However, the production process is very different and requires elaborate manual actions (everting) or a little productive automated production (slipping in the braiding process). Only the flange components themselves are manufactured, which in turn must then be mounted on the actual shaft body. The required connection technology requires an unfavorable loss of lightweight design for the entire component.

In the publication DE 19 538 360 C1 a drive shaft is described, which has a mounted in the injection molding flange. Again, in principle, a semi-finished tube for Application come. In the publication DE 19 538 360 C1 a completely short-fiber-reinforced thermoplastic flange is used, which forms an undercut via holes drilled in the fiber composite pipe in advance. The fibers of the hollow tube are thus not formed from the regular cylindrical shape.

From the company CENTA Kirschey a prototype of a fiber composite drive shaft is known, in which a predominantly made of short fiber reinforced thermoplastic injection molding compound shim is used. But this is sprayed onto a toothed metallic sleeve, which in turn is glued into the fiber composite shaft body. Elaborate adhesive pretreatment steps are necessary here, the transmittable axial force is quite low and the load capacity overall is rather low due to the absence of connecting reinforcing fibers between the shaft body and the shim.

The invention is therefore an object of the invention to provide a method for the production of load introduction flanges on fiber-reinforced hollow profiles with thermoplastic matrix, which is designed so suitable that loads (axial forces, torques and / or bending moments, if necessary) material and flow oriented in direction fiber reinforced Hollow profile semi-finished products are transmitted, the formation of load discharges at any length of the semifinished product must be able to be done at the ends of the semi-finished blanks. It should be possible to a largely automated production technology implementation.

The object is solved by the features of patent claim 1.

• – Erwärmen eines Hohlprofilendabschnitts des faserverstärkten Hohlprofils,
• – Aufdrücken des erwärmten Hohlprofilendabschnitts auf einen Formdom eines Werkzeuges,
• – Aufweitung zumindest eines Hohlprofilrandteils des Hohlprofilendabschnitts zur Ausbildung einer Flansch-Struktur auf dem Formdom,
• – Aufbringen von zusätzlichem Material, das mit der thermoplastischen Matrix des Hohlprofils kompatibel ist, auf die vorgeformte Flansch-Struktur ab einem festgelegten Umfang auf dem Hohlprofilendabschnitt in einem geschlossenen Werkzeug,
• – Erzeugung einer stoffschlüssigen Verbindung zwischen der Matrix des faserverstärkten Hohlprofils und dem auf der Flansch-Struktur aufgebrachten Material zur Ausbildung des finalen Lasteinleitungs-Flansches und
• – Entformung des finalen Lasteinleitungs-Flansches aus dem Werkzeug.

The process for the production of load introduction flanges on fiber-reinforced hollow profiles with thermoplastic matrix for functional hollow structures by means of a tool
according to the characterizing part of patent claim 1 has at least the following steps:

• Heating a hollow profiled end section of the fiber-reinforced hollow profile,
• Pressing the heated hollow profile end section onto a molding dome of a tool,
• Widening at least one hollow profile edge part of the hollow profile end section to form a flange structure on the molded dome,
• Applying additional material compatible with the thermoplastic matrix of the hollow profile to the preformed flange structure from a fixed circumference on the hollow profile end portion in a closed tool,
• - Forming a material connection between the matrix of the fiber-reinforced hollow profile and the material applied to the flange structure material to form the final load introduction flange and
• - Removal of the final load introduction flange from the tool.

By pressing in particular textile-reinforced structural areas can also arise a form-fitting connection portion.

The heating of the hollow profile end section can, for. B. with an external heating before pressing the Hohlprofilendabschnitts or with an inner heating located in the cone during the pressing.

In the expansion of the hollow profile edge portion results in a reduction of the wall thickness or dilution / taper of the original hollow profile thickness D at least in the region of the hollow profile edge portion.

A comparison can be made between the initial diameter D _{R of} the hollow profile and the diameter D _{E of} the hollow profiled edge part determined according to the diameter widening for determining the taper and the amount of injection molding compound or molding compound of the additional material.

The application of the additional material to the flange structure can be carried out by the injection / pressing of a fiber-reinforced injection molding compound or a molding compound.

Furthermore, the application of additional material can be carried out by inserting fiber-reinforced thermoplastic.

As an additional material, at least one fiber-reinforced thermoplastic ring or a molding compound reinforcing the hollow profile edge part can be used circumferentially in the inner region of the hollow profile edge part.

The generation of a cohesive connection of all contact partners can also be achieved by pressing. In addition, micro-teeth on the fiber level can also be used to achieve form-fitting parts in the transmission of force. This is especially true for textile reinforcements.

The generation of a final cohesive connection of the respective contact partners from the positive connection can be achieved by heating all the appropriate contact partners.

On the other hand, the molded dome / cone can also have an internal heating with a predetermined heating temperature T, with which the Hohlprofilendabschnitt can be heated in the direction of the hollow profile edge part during the pressing and thereby expands the hollow profile edge portion.

By choosing the heating temperature T of the heaters used, the shear angle of the fibers during manufacture of the load introduction flange can be adjusted within the design of the flange structure.

The flange structure may, for. B. with the aid of a heated above the solidification temperature T _{E of} the thermoplastic matrix material cone with the heating temperature T below the decomposition temperature T _Z with the following relationship: solidification temperature T _E <heating temperature T <decomposition temperature T _Z , be formed, the fibers to the outer edge of the flange Structure are sheared and assume increasingly steeper angles 65 ° to 85 ° relative to the angles of 40 ° to 65 ° in the remaining Hohlprofilendabschnitt based on the hollow profile longitudinal axis, wherein in the transition region of the hollow profile end portion of the shear angle is 40 ° to 85 °.

The cone can also be heated less strongly, wherein the fibers in the fiber-reinforced hollow profile angle shear less, leaving the fiber orientation closer to the initial state, the flange structure with the help of a heated below the Erstamangstemperatur T _{E of} the thermoplastic matrix material cone heating temperature T with the following relationship: heating temperature T <solidification temperature T _E , wherein the fibers are sheared to the outer edge of the flange structure less sheared and the angles 40 ° to 60 ° relative to the angles of 40 ° to 50 ° in the remaining Hohlprofilendabschnitt based on assume the hollow profile longitudinal axis, wherein in the transition region, the range of the shear angle is 40 ° to 60 °.

For this purpose, provided with an internal heating, tempered cone can be used.

It is also possible to use an elastically expandable cone by means of which the structures / shear angles of the fibers in the respective regions of the hollow profiled end section can optionally be set in a variable manner to the fiber-reinforced hollow profile in the regions of the flange structure.

• – einem Hohlprofilendabschnitt,
• – einem erweiterten Hohlprofilrandteil des Hohlprofilendabschnitts,
• – einem Anspritzteil/Pressteil, das vom Hohlprofilrandteil aus bis zu einem vorgegebenen Umfangs-Bereich des Hohlprofilendabschnitts angelagert ist und zumindest teilweise den bearbeiteten Hohlprofilendabschnitt überlagert, wobei
• – eine zumindest stoffschlüssige Verbindung des Kontaktes des bearbeiteten Hohlprofilendabschnitts und des Anspritzteils/Pressteils ausgebildet ist.

The load introduction flange according to the invention on a fiber-plastic composite with thermoplastic matrix for functional hollow structures, produced by the aforementioned method, consists at least of

• A hollow profile end section,
• An expanded hollow profile edge part of the hollow profile end section,
• - An Anspritzteil / pressing part, which is attached from the hollow profile edge part up to a predetermined peripheral region of the hollow profile end portion and at least partially superimposed on the processed hollow profile end portion, wherein
• - An at least cohesive connection of the contact of the machined hollow profile end portion and the Anspritzteils / pressing part is formed.

By pressing in particular textile-reinforced structural areas can also arise a form-fitting connection portion.

The fiber-reinforced hollow profile with thermoplastic matrix may be tubular.

The attached Anspritzteil / pressing part can be provided for the alignment and reinforcement of the tapered hollow profile wall thickness D _JW to the hollow profile wall thickness D _{RW of} the remaining hollow section end portion.

The injection-molded part / pressing part can preferably be provided with functional elements, in particular with screw-down boreholes.

In this case, the fiber orientation can be influenced by the temperature control of expanding-mandrel / mandrel / cone and be carried out about low for the initiation of torsional loads. Thus, in contrast to the known flanges with thermoset matrix, a load and load-oriented load introduction structure with a novel and significantly improved degree of automation is produced with very short cycle times. In addition to the expansion of the flange with a tempered cone but can also be used with an elastically expandable cone. Then the fibers are primarily fanned out and sheared less.

Possibly occurring material shortage at the outlet of the cone can be compensated with a fiber-reinforced injection molding compound or molding compound, so that a final contour accurate component is formed. In this case, functional surfaces such as bearing seats can be transformed with. Other manufacturing steps such as machining a flange edge can be omitted.

It is essential to reshape the ends of directed fiber-reinforced hollow profiles with the aim of forming a flange or flange, in which / which axial and bending loads, but in particular Torsionsmomente can be initiated. Here, the forming capacity of the hollow profile / tube semi-finished used used mostly only a limited diameter extension. The fiber orientation can be carried out advantageously without further effort, however, the wall thickness decreases with increasing diameter.

In order to produce a heavy-duty flange, additional material compatible with the thermoplastic matrix of the hollow profile / tube must therefore be applied beyond a certain diameter. This is done by inserting fiber-reinforced thermoplastic rings and / or spraying / pressing a fiber-reinforced molding compound. By heating all contact partners to a sufficient temperature level, a cohesive connection can be achieved.

• – Hohlprofilendbereich erwärmen,
• – auf temperierten Formdom aufpressen,
• – vorgeformte Flansch-Struktur auf einen Dom mit faserverstärkten Thermoplast-Ringen oder Pressmasse aufdrücken,
• – verpressen,
• – entformen.

The production is briefly divided into the process steps

• - heat the hollow section end area,
• - press on tempered form dome,
• - press pre-formed flange structure onto a dome with fiber-reinforced thermoplastic rings or molding compound,
• - press,
• - demould.

Further advantageous process sequences are possible, for example using injection molding compound.

Further embodiments of the method and the flange are specified in further subclaims.

The invention will be described by means of several embodiments with reference to several drawings.

Show it:

1 a schematic representation of a formed as a drive shaft fiber reinforced hollow profile in the form of a fiber-thermoplastic composite (FTV) hollow profile with both end load application flanges,

1a a cross-sectional view AA of one of the load introduction flanges after 1 .

2 a schematic representation of the manufacturing process of a flange with the steps: heating, widening and closing tool, injection molding and demolding, wherein

2a the step of heating the hollow profile end section of the fiber-reinforced hollow profile prior to pressing on a mold dome / cone as a tool inner part,

2 B the step of pressing the heated Hohlprofilendabschnitts and expanding the hollow profile edge portion and bringing the outer tool part to the endaufgeweiteten and domgestützten heated hollow profile end portion,

2c the step of closing the tool by applying the tool outer part at least to the heated hollow profile end portion and the step of molding injection molding compound to the hollow profile end portion,

2d the step of demolding the cooled load introduction flange after opening the tool and a schematic side view of the load introduction flange with screwing holes according to 1a demonstrate,

3 exemplary embodiments of the flange, wherein

3a a flange with injected portion of molding compound,

3b a flange with pressed-on FTV rings,

3c show a flange with pressed-on FTV rings including a short fiber reinforced molding compound or injection molding compound,

4 schematic representations of steps for producing a flange structure with a tempered above the solidification temperature T _{E of} the matrix material cone and resulting fiber orientations on the flange structure, wherein when heated, the solidification temperature T _{E of} the matrix material is smaller than the set heating temperature T and less than the decomposition temperature T _{Z of} the matrix material is and where

4a a cone with a heater for heating the hollow profile end portion during the pressing,

4b the over the cone by pressing applied hollow profile end with expanded hollow profile edge portion and

4c the flange structure with the occurred fiber shearing in the final phase of the pressing, wherein a maximum shear angle of 85 ° of the fibers is formed in the hollow profile edge portion to the hollow profile longitudinal axis, show

5 schematic representations of steps for the production of a flange structure with a tempered below the solidification temperature T _{E of} the matrix material cone and therefrom resulting fiber orientations on the flange structure, wherein the set heating temperature T is smaller than the solidification temperature T _{E of} the matrix material and wherein

5a a heated cone is provided with an internal heating for heating the hollow profile end portion during the pressing,

5b the over the heated tempered cone during the Aufdrückens applied hollow profile end section with extended hollow profile edge part and

5c the flange-semi-finished with the occurred fiber shearing in the final phase of the pressing, wherein a maximum shear angle of 60 ° of the fibers of the hollow profile edge portion is formed to the hollow profile longitudinal axis show.

In 1 is a schematic representation of a drive shaft 1 formed fiber-thermoplastic composite (FTV) hollow sections 2 with double-sided load introduction flanges 3 . 4 shown, where 1a a cross-sectional view AA of one of the load introduction flanges 4 in a first form with respect to the drive shaft 1 and in a second form with respect to the manufacture of the flange 4 to 2 is specified.

2 shows a possible technological implementation of the described invention, in which the expansion and the flange molding in a process sequence take place, wherein in 2 a schematic representation of the manufacturing process of a flange 4 with the steps: heating, widening and closing tools, injection molding and demoulding, whereby

2a the step of heating 6 of the hollow profile end section 5 of the fiber-reinforced hollow profile 2 before pressing 7 on a mold dome / cone 8th as a tool inner part,

2 B the step of imposing 7 the heated hollow profile end section 5 and expanding 26 of the hollow profile edge part 9 and bringing a tool outer part 29 at the endaufgeweiteten and domgestützten heated Hohlprofilendabschnitt 5 .

2c the step of closing 30 of the tool 10 by applying the tool outer part 29 at least on the heated hollow profile end section 5 and the step of molding 20 of injection molding compound to the hollow profile end section 5 and

2d the step of demolding the cooled load introduction flange 4 after opening the tool 10 and a schematic side view of the load introduction flange 4 with bolting holes 14 according to 1a demonstrate.

In 3 are exemplary embodiments of the flange 41 shown, where

3a a flange 4 with molded part 11 of molding compound,

3b a flange 4 with pressed FTV-rings 22 . 23 . 24 and

3c a flange 4 with pressed FTV-rings 22 . 23 . 24 including a short fiber reinforced molding compound 25 or injection molding compound.

In 4 FIG. 3 are schematic illustrations of steps for making the flange structure. FIG 41 with a cone tempered above the solidification temperature T _{E of} the matrix material 8th and resulting fiber orientations on the flange structure 41 shown, wherein upon heating, the solidification temperature T _{E of} the matrix material is smaller than the set heating temperature T and this in turn is less than the decomposition temperature T of the matrix material and wherein

4a a cone 8th with a heater for heating 6 of the hollow profile end section 5 during the pressing 7 .

4b the over the cone 8th by pressing 7 applied hollow profile end section 5 with extended hollow profile edge part 9 and

4c the flange structure 41 with the occurred fiber shearing in the final phase of pressing 7 , wherein a maximum shear angle of 85 ° of the fibers 16 in the hollow profile edge part 9 to the hollow profile longitudinal axis 15 educated, show,

In 5 In other schematic representations, steps are to fabricate the flange structure 41 with a temperature-controlled below the solidification temperature T _{E of} the matrix material cone 8th and resulting fiber orientations on the flange structure 41 shown, wherein the set heating temperature T is smaller than the solidification temperature T _{E of} the matrix material, and wherein

5a a heated cone 8th with an internal heating 13 for heating the Hohlprofilendabschnitts 5 during the pressing 7 is provided

5b the over the heated tempered cone 8th during the pressing 7 applied Hohlprofilendabschnitt 5 with extended hollow profile edge part 9 and

5c the flange structure 41 with the occurred fiber shearing in the final phase of pressing 7 , wherein a maximum shear angle of 60 ° of the fibers 16 of the hollow profile edge part 9 to the hollow profile longitudinal axis 15 is trained, show.

Advantageous configurations of the flange structure include encapsulation and compression of fiber-thermoplastic composite (FTV) rings that provide directional long or continuous fiber reinforcement, as in U.S. Pat 3 is shown.

When expanding the FTV hollow profile 2 can about the temperature control 6 of the cone 8th the behavior of the fiber material are influenced or controlled. 4c shows the schematic fiber flow on a flange structure 41 which is heated by means of a cone heated above the solidification temperature T _{E of} the thermoplastic matrix material 8th with the heating temperature T below the decomposition temperature T _Z with the following relationship: solidification temperature T _E <heating temperature T <decomposition temperature T _Z , is formed. The fibers 16 to the outer edge 17 of the cone 8th are severely sheared and take increasingly steeper angles 65 ° to the angles of 40 ° to 65 ° in the remaining Hohlprofilendabschnitt 5 relative to the hollow profile axis 15 at. In the transition area 18 the range of the shear angle is 40 ° to 85 °.

In 5 becomes the cone 8th less heated, resulting in the FTV hollow profile 2 the fibers 16 shear less. The fiber orientation remains closer to the initial state. This shows 5c in which the schematic fiber profile on a flange structure 41 , which by means of a heated under the solidification temperature T _{E of} the thermoplastic matrix material cone 8th with the heating temperature T with the following relationship: heating temperature T <solidification temperature T _E , is formed. The fibers 16 to the outer edge 17 of the cone 8th are less sheared and take the angle 40 ° to 60 ° with respect to the angles of 40 ° to 50 ° in the rest Hohlprofilendabschnitt 5 based on the hollow profile longitudinal axis 15 at. In the transition area 18 the range of the shear angle is also 40 ° to 60 °.

The hollow profile 2 consists of a fiber-thermoplastic composite, ie a combination of reinforcing fibers (eg glass fibers, basalt fibers, carbon fibers) and a thermoplastic matrix material (eg PA, PPA, PPS, PEEK). The orientation of the fibers 16 can be adapted to the loads of the respective application. For predominantly tension and pressure loaded profiles 2 are the reinforcing fibers 16 predominantly axially oriented. For predominantly torsionally loaded profiles 2 are the reinforcing fibers 16 predominantly oriented at an angle of ± 45 °. The profiles 2 can be used continuously in z. B. a pultrusion process or discontinuously in z. B. a Schlauchblasverfahren be prepared. You can have a constant, but also one over the length of the profile 2 have varying cross-section.

It can be made an additional reinforcement of the hollow profile.

There is the possibility of the hollow profile 2 in the area of the load introduction area with additional layers (not shown) to reinforce, allowing a failure in the undisturbed area of the profile 2 is shifted, reducing the load capacity of the profile 2 can be fully exploited. The layers may be warmed up during the heating phase of the integration of the load introduction element and cohesively with the hollow profile during Anspritzvorgangs 2 get connected.

The injection molding compound used is described in more detail below: The injection molding compound can be the matrix material of the hollow profile 2 correspond. Depending on the combination of materials, the injection-molding compound can be firmly bonded to the thermoplastic matrix of the hollow profile 2 tie.

• – Erwärmen 6 eines Hohlprofilendabschnitts 5 des faserverstärkten Hohlprofils 2,
• – Aufdrücken 7 des erwärmten Hohlprofilendabschnitts 5 auf einen Formdom 8 eines Werkzeuges 31,
• – Ausweitung zumindest eines Hohlprofilrandteils 9 des Hohlprofilendabschnitts 5 zur Ausbildung einer Flansch-Struktur 41 auf dem Formdom 8, wobei die Hohlprofilstärke D zumindest im Bereich des Hohlprofilrandteils 9 ein Reduktion der Wandstärke erfährt 10,
• – Aufbringen 27 von zusätzlichem Material 11, das mit der thermoplastischen Matrix des Hohlprofils 2 kompatibel ist, auf das vorgeformte Flansch-Halbzeug 41 ab einem festgelegten Umfang 12 auf dem Hohlprofilendabschnitt 5 in einem geschlossenen Werkzeug 31,
• – Erzeugung zumindest einer stoffschlüssigen Verbindung zwischen der Matrix des faserverstärkten Hohlprofils 2 und dem auf der Flansch-Struktur 41 aufgebrachten Material 11 zur Ausbildung des finalen Lasteinleitungs-Flansches 3, 4 und
• – Entformung des finalen Lasteinleitungs-Flansches 3, 4 aus dem Werkzeug 31.

In summary, the method for the production of load introduction flanges 3 . 4 on a fiber-reinforced hollow profile 2 with thermoplastic matrix for functional hollow structures 1 by means of a tool 31 at least essentially the following steps:

• - heating 6 a Hohlprofilendabschnitts 5 of the fiber-reinforced hollow profile 2 .
• - Press on 7 the heated hollow profile end section 5 on a mold dome 8th a tool 31 .
• - Expansion of at least one hollow profile edge part 9 of the hollow profile end section 5 for forming a flange structure 41 on the form dome 8th , wherein the hollow profile thickness D at least in the region of the hollow profile edge part 9 a reduction of the wall thickness experiences 10 .
• - Apply 27 of additional material 11 that with the thermoplastic matrix of the hollow profile 2 is compatible with the preformed flange semi-finished product 41 from a fixed extent 12 on the hollow profile end section 5 in a closed tool 31 .
• - Generation of at least one cohesive connection between the matrix of the fiber-reinforced hollow profile 2 and that on the flange structure 41 applied material 11 to Formation of the final load introduction flange 3 . 4 and
• - Removal of the final load introduction flange 3 . 4 from the tool 31 ,

The heating of the hollow profile end section 5 can with an exterior heating 21 before pressing 7 of the hollow profile end section 5 or with a cone 8th located interior heating 13 during the pressing 7 be performed.

A determination of the reduction of the wall thickness or the rejuvenation 10 of the hollow profile edge part 9 the preformed flange structure 41 can be carried out if necessary.

In this case, a comparison between the output diameter D _{R of} the hollow profile 2 and the diameter D _{E of} the hollow profile edge part determined according to the diameter extension 9 for the determination of rejuvenation 10 and the applied injection molding compound or molding compound of the additional material 11 be performed.

The application 27 of additional material 11 on the flange structure 41 can be sprayed / pressed 20 a fiber-reinforced injection molding compound or a molding compound.

Furthermore, the application can 27 of additional material 11 by inserting fiber-reinforced thermoplastic rings 22 . 23 . 24 be performed.

As additional material 11 can be at least one fiber reinforced thermoplastic ring 22 . 23 . 24 or a hollow profile edge part 9 reinforcing molding compound 25 circumferentially in the inner region of the hollow profile edge part 9 be used. The supporting molding compound 25 essentially serves to fill the cavities present there.

The generation of a final cohesive connection of the respective contact partners 9 . 10 . 22 . 23 . 24 . 25 From a positive connection can by heating all applicable, a positive connection having contact partners 9 . 10 . 22 . 23 . 24 . 25 be achieved.

The form dome / cone 8th can, as in 5 is shown, on the other hand, an internal heating 13 having a predetermined heating temperature T, with which the Hohlprofilendabschnitt 5 in the direction of the hollow profile edge part 9 out while pushing 7 can be heated while the hollow profile edge part 9 extended.

By choosing the heating temperature T of the heaters used 13 or 21 can the shear angle of the fibers 16 during the manufacture of the load introduction flange 3 . 4 within training of the flange structure 41 be set.

The flange structure 41 can z. B. with the aid of a heated above the solidification temperature T _{E of} the thermoplastic matrix material cone 8th with the heating temperature T below the decomposition temperature T _Z with the following relationship: solidification temperature T _E <heating temperature T <decomposition temperature T _Z , wherein the fibers 16 to the outer edge 17 of the flange semi-finished product 41 sheared and increasingly steeper angles 65 ° to 85 ° with respect to the angles of 40 ° to 65 ° in the remaining Hohlprofilendabschnitt 5 based on the hollow profile longitudinal axis 15 assume, being in the transition area 18 of the hollow profile end section 5 the range of the shear angle is 40 ° to 85 °.

The cone 8th can also be less heated, with the FTV hollow profile 2 the fibers 16 Shear less angle shear, the fiber orientation remains closer to the initial state, the flange semi-finished 41 with the help of a below the solidification temperature T _{E of} the thermoplastic matrix material lying heating temperature T heated cone 8th with the following relationship: heating temperature T <solidification temperature T _E , is formed, wherein the fibers 16 to the outer edge 17 the flange structure 41 directed less sheared and the angles 40 ° to 60 ° relative to the angles of 40 ° to 50 ° in the rest Hohlprofilendabschnitt 5 based on the hollow profile longitudinal axis 15 assume, being in the transition area 18 the range of the shear angle is 40 ° to 60 °.

This can be one with an internal heating 13 provided, tempered cone 8th be used.

It can also be an elastically expandable cone 8th can be used, with the optional structures / shear angle of the fibers 16 in respective areas 9 . 10 . 18 . 19 of the hollow profile end section 5 the fiber reinforced hollow profile 2 in the areas of the flange structure 41 can be set / set variably.

• – einem Hohlprofilendabschnitt 5,
• – einem erweiterten Hohlprofilrandteil 9 des Hohlprofilendabschnitts 5,
• – einem Anspritzteil/Pressteil 11, das vom Hohlprofilrandteil 9 aus bis zu einem vorgegebenen Umfangs-Bereich 12 des Hohlprofilendabschnitts 5 angelagert ist und teilweise den bearbeiteten Hohlprofilendabschnitt 5 überlagert, wobei
• – zumindest eine stoffschlüssige Verbindung des Kontaktes des bearbeiteten Hohlprofilendabschnitts 5 und des Anspritzteils/Pressteils 11 ausgebildet ist.

The load introduction flange according to the invention 3 . 4 on a fiber-reinforced hollow profile 2 with thermoplastic matrix for functional hollow structures 1 , made with the aforementioned method, consists at least of

• - A hollow profile end section 5 .
• - An expanded hollow profile edge part 9 of the hollow profile end section 5 .
• - An Anspritzteil / pressed part 11 , that of the hollow profile edge part 9 out to a given perimeter area 12 of the hollow profile end section 5 is attached and partially the machined Hohlprofilendabschnitt 5 superimposed, where
• - At least one cohesive connection of the contact of the processed hollow profile end portion 5 and the Anspritzteils / pressed part 11 is trained.

The fiber-reinforced hollow profile 2 with thermoplastic matrix may be tubular.

The attached Anspritzteil / pressed part 11 can for the approximation and reinforcement of the tapered hollow profile wall thickness D _JW to the hollow profile wall thickness D _{RW of} the remaining hollow profile end portion 5 be provided.

The molded part / pressed part 11 may preferably be with functional elements, in particular with threaded boreholes 14 be provided.

• – der Verwendung von endlos gefertigten und damit kostengünstigen Halbzeugen,
• – einer Fertigung beliebiger Längen der Thermoplast-Hohlprofil-Strukturen ohne zusätzliche Werkzeugkosten,
• – einer belastungs- und kraftflussgerecht einstellbaren Faserorientierung im Lasteinleitungsbereich während der schnellen und effizienten Umformung ohne zusätzliche Verfahrensschritte,
• – einem automatisierbaren Prozess mit sehr kurzen Taktzeiten,
• – einen Prozess, in dem zusätzliche Funktionsbereiche wie etwa Lagersitze mit ausgebildet (bzw. angespritzt) werden können, wobei eine weitere Bearbeitung von Funktions-Hohlprofilen mit Flanschen vermieden wird,
• – einem stoffgleichen System aus flansch- und lasttragender Hohlprofilstruktur, wobei auch Vorteile hinsichtlich Kontaktkorrosion und thermisch induzierten Spannungen in Folge unterschiedlicher Ausdehnungskoeffizienten auftreten.

The advantages of the method according to the invention and the produced load introduction flange according to the invention consist in

• The use of endlessly manufactured and therefore inexpensive semi-finished products,
• A production of any lengths of the thermoplastic hollow profile structures without additional tooling costs,
• A load orientation and fiber flow adjustable fiber orientation in the load introduction area during the rapid and efficient forming without additional process steps,
• - an automatable process with very short cycle times,
• A process in which additional functional areas, such as bearing seats, can be formed (or injection-molded), avoiding further machining of functional hollow profiles with flanges,
• - A fabric-like system of flange and load-bearing hollow profile structure, which also benefits in terms of contact corrosion and thermally induced stresses due to different expansion coefficients occur.

LIST OF REFERENCE NUMBERS

1

Drive Shaft / Function hollow structure

2

Fiber-thermoplastic composite hollow profile / fiber-reinforced hollow profile

3

First load introduction flange

4

Second load introduction flange

41

Flange structure

5

Hohlprofilendabschnitt

6

Step heating

7

Step Press

8th

Forming mandrel / cone

9

Hollow section rim portion

10

Rejuvenation / wall reduction

11

Molded-/ pressed part

12

Pages / circumferential region

13

interior heating

14

Screw-hole

15

Hollow profile longitudinal axis

16

Fiber / gain fiber

17

Outer edge of the flange structure

18

Transition area of the flange structure

19

Hollow profile longitudinal region

20

Step injecting

21

external heating

22

First thermoplastic ring

23

Second thermoplastic ring

24

Third thermoplastic ring

25

Internal molding compound

26

Step expanding

27

Step up

28

Step Press

29

Tool outer part

30

Step Close

31

Tool

D _R

Hollow output profile diameter

D _E

extended hollow profile diameter

D _JW

tapered hollow profile wall thickness

D _RW

Output hollow section wall thickness

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 4414384 A1 [0008]
• DE 19906618 A1 [0008]
• CN 191677 C [0009]
• DE 000002058015 A [0009]
• DE 3608754 C2 [0009]
• DE 4442268 C1 [0009]
• US 2009/0308477 A1 [0009]
• EP 0413677 A1 [0009]
• WO 1998020263 A1 [0009]
• DE 4014400 A1 [0010]
• EP 0307112 B1 [0010]
• US 5724715A [0010]
• DE 19538360 C1 [0011, 0011]

Claims (19)

Method for producing load introduction flanges ( 3 . 4 ) on fiber-reinforced hollow profiles ( 2 ) with thermoplastic matrix for functional hollow structures ( 1 ) by means of a tool ( 31 ), characterized at least by the following steps, - heating ( 6 ) of a hollow profile end section ( 5 ) of the fiber-reinforced hollow profile ( 2 ), - press ( 7 ) of the heated hollow profile end section ( 5 ) on a molded dome ( 8th ) of a tool ( 31 ), - expansion of at least one hollow profile edge part ( 9 ) of the hollow profile end section ( 5 ) for forming a flange structure ( 41 ) on the molded dome ( 8th ), - application ( 27 ) of additional material ( 11 ), which with the thermoplastic matrix of the hollow profile ( 2 ) is compatible with the preformed flange structure ( 41 ) from a fixed extent ( 12 ) on the hollow profile end section ( 5 ) in a closed tool ( 31 ), - Generation of at least one cohesive connection between the matrix of the fiber-reinforced hollow profile ( 2 ) and on the flange structure ( 41 ) applied material ( 11 ) for forming the final load introduction flange ( 3 . 4 ) and - removal of the final load introduction flange ( 3 . 4 ) from the tool ( 31 ). A method according to claim 1, characterized in that the heating of the hollow profile end portion ( 5 ) with an external heating ( 21 ) before pressing ( 7 ) of the hollow profile end section ( 5 ) or with a cone ( 8th ) located inside heating ( 13 ) during the pressing ( 7 ) is carried out. Method according to claim 1, characterized in that a determination of the reduction in wall thickness and rejuvenation ( 10 ) of the hollow profile edge part ( 9 ) of the preformed flange structure ( 41 ) is carried out. Method according to claim 1, characterized in that the application ( 27 ) of additional material ( 11 ) on the flange structure ( 41 ) by the injection / pressing ( 20 ) is performed a fiber-reinforced injection molding compound or a molding compound. Method according to claim 1, characterized in that the application ( 27 ) of additional material ( 11 ) by inserting fiber-reinforced thermoplastic rings ( 22 . 23 . 24 ) is carried out. Process according to claims 4 and 5, characterized in that as additional material ( 11 ) at least one fiber-reinforced thermoplastic ring ( 22 . 23 . 24 ) and / or a hollow profile edge part ( 9 ) reinforcing molding compound ( 25 ), circumferentially in the inner region of the hollow profile edge part ( 9 ) is used. A method according to claim 1, characterized in that a comparison between an initial diameter D _{R of} the hollow profile ( 2 ) and the diameter D _{E of} the hollow profile edge part (D) 9 ) for determining an applied mass of the additional material ( 11 ) is carried out. A method according to claim 1, characterized in that the generation of a cohesive connection of all contact partners ( 9 . 10 . 22 . 23 . 24 . 25 ) by pressing ( 28 ) is achieved. Method according to claim 1 or 8, characterized in that the generation of a final cohesive connection of the respective contact partners ( 9 . 10 . 22 . 23 . 24 . 25 ) from a positive connection by heating all, the form-locking connection having contact partners ( 9 . 10 . 22 . 23 . 24 . 25 ) is achieved. Method according to claim 1, characterized in that the molding dome / cone ( 8th ) an internal heating ( 13 ) having a predetermined heating temperature T, with which the hollow profile end portion ( 5 ) in the direction of the hollow profile edge part ( 9 ) while pressing ( 7 ) and thereby the hollow profile edge part ( 9 ). A method according to claim 1, characterized in that by the choice of the heating temperature T, the shear angle of the fibers ( 16 ) during the manufacture of the load introduction flange ( 3 . 4 ) within the flange structure ( 41 ) is set. A method according to claim 11, characterized in that the flange structure ( 41 ) with the aid of a cone heated above the solidification temperature T _{E of} the thermoplastic matrix material (US Pat. 8th ) with the heating temperature T below the decomposition temperature T _Z with the following relationship: solidification temperature T _E <heating temperature T <decomposition temperature T _Z , wherein the fibers ( 16 ) to the outer edge ( 17 ) of the flange structure ( 41 ) and increasingly steeper angles 65 ° to 85 ° with respect to the angles of 40 ° to 65 ° in the remaining hollow section end section (FIG. 5 ) relative to the hollow profile longitudinal axis ( 15 ), whereas in the transitional area ( 18 ) of the hollow profile end section ( 5 ) the range of the shear angle is 40 ° to 85 °. Method according to claim 11, characterized in that the cone ( 8th ) is heated less strongly, whereby in the fiber-reinforced hollow profile ( 2 ) the fibers ( 16 ) shear less angularly with the fiber orientation remaining closer to the initial state, the flange structure ( 41 ) with the aid of a below the solidification temperature T _{E of} the thermoplastic matrix material lying heating temperature T heated cone ( 8th ) with the following relationship: heating temperature T <solidification temperature T _E , wherein the fibers ( 16 ) to the outer edge ( 17 ) of the flange structure ( 41 ) sheared less strongly and the angles 40 ° to 60 ° relative to the angles of 40 ° to 50 ° in the remaining Hohlprofilendabschnitt ( 5 ) relative to the hollow profile longitudinal axis ( 15 ), whereas in the transitional area ( 18 ) the range of the shear angle is 40 ° to 60 °. Process according to claims 11 to 13, characterized in that one with an internal heating ( 13 ) tempered cone ( 8th ) is used. Method according to claim 1, characterized in that an elastically expandable cone ( 8th ), with which optionally the structures / shear angles of the fibers ( 16 ) in respective areas ( 9 . 10 . 18 . 19 ) of the hollow profile end section ( 5 ) the fiber-reinforced hollow profile ( 2 ) in the areas of the flange structure ( 41 ) can be set variably. Load introduction flange ( 3 . 4 ) on fiber-reinforced hollow profiles ( 2 ) with thermoplastic matrix for functional hollow structures ( 1 ), produced by a method according to claims 1 to 15, at least consisting of - a hollow profile end section ( 5 ), - an expanded hollow profiled edge part ( 9 ) of the hollow profile end section ( 5 ), - a Anspritzteil / pressed part ( 11 ), of the hollow profile edge part ( 9 ) up to a predetermined circumferential range ( 12 ) of the hollow profile end section ( 5 ) is attached and at least partially the processed Hohlprofilendabschnitt ( 5 superimposed, wherein - at least one cohesive connection of the contact of the machined Hohlprofilendabschnitts ( 5 ) and the Anspritzteils / pressed part ( 11 ) is trained. Load introduction flange according to claim 16, characterized in that the fiber-reinforced hollow profile ( 2 ) is tubular with thermoplastic matrix. Load introduction flange according to claim 16 or 17, characterized in that the injection part / pressing part ( 11 ) for the alignment and reinforcement of the tapered hollow profile wall thickness D _JW to the output hollow profile wall thickness D _{RW of} the remaining hollow profile end portion ( 5 ) is provided. Load introduction flange according to claims 16 to 18, characterized in that the injection part / pressing part ( 11 ) with functional elements, in particular with threaded boreholes ( 14 ) is provided.

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