SYSTEM AND METHOD FOR THE CONTINUOUS PRODUCTION OF CURVED PREFORMS

Abstract

The invention relates to a system (10) for the continuous production of a curved profiled preform (5) from flat, semi-finished fiber products (1), and to a method for this purpose, wherein first belt sections (3a, 3b) are formed by a shaping device and subsequently the semi-finished fiber product is sheared with the aid of two rollers (51, 52) which are arranged in the conveying direction at a distance from one another; wherein the web height of the curved profiled mold can be varied by linearly displaceable rollers (61, 62).

Claims

1. A system for the continuous production of a curved profiled preform from planar semi-finished fibrous products, for the production of a fiber-composite component, said system comprising a fiber supply installation which is configured for providing the semi-finished fibrous products; a forming installation which is configured for forming a first belt portion from a first lateral portion of the semi-finished fibrous product and for forming a second belt portion from a second lateral portion; a shearing installation which has at least two rotating roller elements that are disposed so as to be mutually spaced apart in a conveying direction and are configured so as to bear in a force-fitting manner on one of the belt portions and to interact with the latter in such a manner that shearing of the fibers between the roller elements in order for the curvature of the profiled preform to be formed is caused by a rotational speed differential set between the roller elements; a cross-sectional modification installation which is different from the shearing installation and which has a first rotating roller element which bears in a force-fitting manner on the first belt portion and has a second rotating roller element which bears in a force-fitting manner on the second belt portion, wherein at least one of the roller elements is disposed so as to be transverse to the conveying direction and interacts with the respective belt portion in such a manner that a web height modification of a web portion that is defined between the belt portions is caused during the production of the curved profiled preform by a movement of the roller element that is transverse to the conveying direction; and a controller installation which is adapted for actuating the shearing installation in order for the rotational speed differential to be set and for actuating the cross-sectional modification installation in order for the web height of the web portion to be set.

2. The system as claimed in claim 1, wherein, in order for a roller element pair to be formed, a counter-rotating roller element is disposed so as to be opposite at least one roller element, wherein the respective portion of the semi-finished fibrous product is conveyed in a conveying direction between the counter-rotating roller elements of the roller element pair.

3. The system as claimed in claim 2, wherein, in order for a respective roller element pair to be formed, each roller element of the shearing installation and of the cross-sectional modification installation has one opposite counter-rotating roller element.

4. The system as claimed in claim 1, wherein at least one of the roller elements has a first roller element portion and at least one second roller element portion, wherein the first roller element portion has a diameter that is consistent across the length, while the second roller element portion has a diameter that is variable across the length.

5. The system as claimed in claim 4, wherein the sleeve area of the first roller element portion has a coefficient of friction that is higher than that of the sleeve area of the second roller element portion.

6. The system as claimed in claim 1, further comprising a fiber angle sensor which is configured for determining a fiber angle of the sheared semi-finished fibrous product, wherein the controller installation is adapted for setting the rotational speed differential so as to depend on the fiber angle determined, so as to cause a predefined curvature of the profiled preform.

7. The system as claimed in claim 1, further comprising a belt webbing infeed installation which is configured for infeeding and incorporating additional belt webbings from fibrous material into at least one belt portion.

8. The system as claimed in claim 7, characterized in that the belt webbing infeed installation infeeds the additional belt webbings at the first and/or the second roller element of the cross-sectional modification installation, and incorporates the additional belt webbings into the respective belt portion by way of the first and/or the second roller element of the cross-sectional modification installation.

9. The system as claimed in claim 7, wherein the belt webbing infeed installation is configured for setting a predefined position of the additional belt webbings in relation to the belt height of the respective belt portion.

10. The system as claimed in claim 1, further comprising a cutting installation which is configured for trimming the end contour of the belt portions of the curved profiled preform.

11. The system as claimed in claim 1, wherein at least one of the roller elements of the cross-sectional modification installation, while being displaced transversely to the conveying direction, is configured so as to be pivotable or tiltable in a semi-finished fibrous product plane that is defined by the semi-finished fibrous product bearing in a force-fitting manner on said roller element.

12. A method for the continuous production of a curved profiled preform from planar semi-finished fibrous products, for the production of a fiber-composite component, said method comprising the following steps: providing a planar semi-finished fibrous product; forming the planar semi-finished fibrous product such that a first belt portion is formed from a first lateral portion of the semi-finished fibrous product, and a second belt portion is formed from a second lateral portion of the semi-finished fibrous product; shearing the semi-finished fibrous product in that two rotating roller elements that are disposed so as to be mutually spaced apart in a conveying direction bear in a force-fitting manner on one of the belt portions, and a rotational speed differential between the two roller elements is set such that shearing of the fibers between the roller elements in order for the curvature of the profiled preform to be produced is caused; and subsequently modifying a web height of a web portion that is defined between the belt portions, in that two roller elements in each case bear in a force-fitting manner on one belt portion, and at least one of the roller elements is moved transversely to the conveying direction such that a predefined web height is set.

13. The method as claimed in claim 12, further comprising determining a fiber angle of the sheared semi-finished fibrous product by a fiber angle sensor, wherein the rotational speed differential during the shearing of the fibers is set so as to depend on the determined fiber angle, in order to cause a predetermined curvature of the profiled preform.

14. The method as claimed in claim 12, further comprising incorporating additional belt webbings from fibrous material into at least one belt portion.

15. The method as claimed in claim 14, further comprising setting a predefined position of the additional belt webbings in relation to the belt height of the respective belt portion.

16. The method as claimed in claim 12, further comprising trimming of the end contour of the belt portions by a cutting device.

17. The method as claimed in claim 12, wherein during the modification of the web height at least one of the roller elements, while being displaced transversely to the conveying direction of the roller elements, is pivoted or tilted in a semi-finished fibrous product plane that is defined by the semi-finished fibrous product bearing in a force-fitting manner on said roller element.

Description

[0036] The invention will be explained in more detail by means of the appended figures in which:

[0037] FIG. 1 shows a schematic illustration of the system according to the invention;

[0038] FIG. 2 shows a schematic illustration of a roller element pair;

[0039] FIG. 3 shows a perspective illustration of a preform profile.

[0040] FIG. 1 schematically shows the system according to the invention for the production of a curved profiled preform. The profiled preform herein comprises a fibrous material, or is composed thereof, which is used for the production of fiber-composite components in which the fibrous material is infused with a matrix material, and the matrix material is subsequently cured. The curved profiled preform in the cross section herein in each case has belt portions which are bent by a central web portion. Herein, a curvature in the longitudinal direction is to be incorporated into the preform. Profiles of this type can be C-profiles or Z-profiles, for example.

[0041] The system 10 according to the invention for the production of such a curved profiled preform from planar semi-finished fibrous products has a fiber supply installation 20 which has a roll 21 on which the planar semi-finished fibrous product 1 is provided to the system 10.

[0042] The roll 21 is rotatably driven by way of a motor 22 such that the planar semi-finished fibrous product 1 is infed to the individual further stations of the system 10 in as tension-free a manner as possible. In order to be able to equalize variations in the infeed speed, a jockey roller 23 which homogenizes and synchronizes infeeding by way of lift compensation is disposed so as to be downstream of the roller 21 in the conveying direction F. The jockey roller 23 herein can be detected by way of a sensor system such that the motor 22 of the fiber supply installation 20 can be actuated depending on the detected lift.

[0043] The planar semi-finished fibrous product 1 is provided to the indexing installation 30 in this manner. The indexing installation 30 has an indexing roller 31 which extends across the entire width of the planar semi-finished fibrous product 1 and infeeds the planar semi-finished fibrous product to the forming installation 40 so as to be consistent and uniform across the entire width. It is achieved herein by way of the indexing roller 31 that extends across the entire width of the planar semi-finished fibrous product 1 that infeeding of the planar semi-finished fibrous product 1 to the forming installation 40 is at all times performed at the fiber angle that is consistent across the entire width of the planar semi-finished fibrous product such that both forming as well as subsequent shearing can proceed from constant boundary conditions in terms of the fiber angle.

[0044] The lateral portions 2a, 2b of the planar semi-finished fibrous product 1 are bent by means of the forming installation 40 such that respective belt portions 3a, 3b are formed. Forming herein is performed by means of the forming installation 40 in such a manner that the lateral portions 2a, 2b are bent from the planar semi-finished fibrous product 1 so that a web portion 4 is defined between the belt portions 3a, 3b formed. Forming herein can be performed by means of rollers or guide rails or the like.

[0045] The semi-finished fibrous product 1 such formed is now infed to the downstream shearing installation 50 which has two roller element pairs 51 and 52 that are disposed so as to be mutually spaced apart in the conveying direction F. The respective belt portion, this in the exemplary embodiment of FIG. 1 being the belt portion 3a, is guided between the roller elements of the roller element pairs, wherein the belt portion 3a bears in a force-fitting manner on the roller elements of the two roller element pairs 51 and 52.

[0046] The roller elements of the two roller element pairs 51 and 52 herein rotate at dissimilar rotational speeds such that a rotational speed differential is established between the roller elements of the roller element pair 51 and the roller elements of the roller element pair 52, said rotational speed differential leading to shearing of the fibers of the semi-finished fibrous product 1 between the roller element pairs 51 and 52. Shearing herein is at maximum in that belt portion 3a on which the roller element pairs 51 and 52 bear in a force-fitting manner, said shearing extending in a uniformly decreasing manner toward the belt portion 3b where shearing is at minimum or does no longer arise at all, respectively.

[0047] Moreover, at least one further roller element pair 53 which bears in a force-fitting manner on the second belt portion 3b and advantageously has the rotational speed of the first roller element pair 51 of the first belt portion 3a can be disposed on the opposite belt portion 3b.

[0048] A defined curvature in the longitudinal direction which ultimately depends on the rotational speed differential of the two roller element pairs 51 and 52 is incorporated into the semi-finished fibrous product 1 by shearing the fibrous material between the two roller elements 51 and 52.

[0049] The semi-finished fibrous product such sheared is now infed to a cross-sectional modification installation which in the conveying direction F is downstream of the shearing installation 50. The cross-sectional modification installation 60 has at least two roller element pairs 61 and 62, wherein the first roller element pair 61 by way of the roller elements thereof bears in a force-fitting manner on the first belt portion 3a, while the second roller element pair 62 by way of the roller elements thereof bears in a force-fitting manner on the second belt portion 3b. Herein, at least the roller element pair 62 is disposed so as to be displaceable transversely to the conveying direction F such that the distance between the roller element pair 61 and the roller element pair 62 can be modified. More specifically, the roller element pair 62 in the exemplarly embodiment of FIG. 1 is configured such that it can move away from the web portion 4 of the semi-finished fibrous product 1 or move toward the latter. It is achieved on account thereof that the web height of the web portion 4 can be modified in order for curved profiled preforms having a variable web height to be able to be produced. The web height herein is defined as the extent between the first belt portion 3a and the second belt portion 3b.

[0050] The curved profiled preform is subsequently infed to a cutting installation 70 which trims the end contours of the belt portions 3a, 3b such that the latter have substantially the same belt height or a belt height of defined dissimilarity.

[0051] The entire system 10 is controlled with the aid of a controller installation 80, wherein the controller installation 80 is connected in particular to the shearing installation 50 of the cross-sectional modification installation 60 and is adapted for setting the rotational speed differential between the two roller element pairs 51 and 52 according to a predefined nominal curvature, on the one hand, and moreover for actuating the movement of the at least one roller element pair 62 of the cross-sectional modification installation 60 so as to set the desired nominal web height of the web portion 4.

[0052] The system 10 can have a fiber angle sensor 55 which is downstream of the two roller element pairs 51 and 52 and detects a fiber angle of the sheared fibers in the first belt portion 3a, By means of the fiber angle of the sheared fibers such detected, the controller installation 80 can then set the rotational speed differential between the two roller element pairs 51 and 52 such that the desired curvature can be produced. The curvature of the preform is thus directly correlated to the fiber angle of the sheared fibers.

[0053] A belt webbing infeed installation 90 which by way of the roller element pair 61 of the cross-sectional modification installation 60 incorporates an additional belt webbing from fibrous material having a zero degree position of the reinforcement fibers into the outer belt 3a (first belt portion) can furthermore be provided. Herein, a binding agent material can be activated by thermal input, for example, such that the additional belt webbing 91 is fixed to the outside of the first belt portion 3a.

[0054] FIG. 2 schematically shows the roller element pair 62 which is a component part of the cross-sectional modification installation 60 and by way of a linear displacement is moreover provided for varying the web height. The roller element pair 62 has two counter-rotating roller elements 62a and 62b, wherein the second belt portion 3b bears in a force-fitting manner on the roller elements between the roller elements 62a and 62b. The two roller elements 62a and 62b can be displaced transversely to the conveying direction of the semi-finished fibrous products with the aid of a linear motor 63.

[0055] A displacement of the roller element pair 62 to the left thus leads to the height of the belt portion 3b being reduced and the semi-finished fibrous product sliding upward in relation to the roller elements 62a and 62b. The web height is increased in this case. When displaced to the right, the semi-finished fibrous product slides downward, the belt portion 3b being enlarged and the web height being reduced on account thereof.

[0056] The two roller elements 62a and 62b have a first roller element portion 64a and a second roller element portion 64b. The first roller element portion 64a herein has a substantially consistent diameter that is constant across the length of the roller element portion 64a such that the roller element portion 64a of the roller element 62a has a cylindrical shape having a constant cross section. The second roller element portion 64b which has a variable diameter, on account of which a kind of collar is created on the roller element 62a, is located at the upper end of the roller element 62a. A kind of cap is shaped in a corresponding manner thereto on the roller element 62b in the region of the second roller element portion 64b.

[0057] The curvature radius of the semi-finished product that defines the transition from the web portion 4 to the belt portion 3b is post-formed by the variable diameter of this second roller element portion 64b. On account thereof, the forming process per se is further facilitated, on the one hand, and it is moreover prevented that the fibrous material breaks by virtue of an excessively tight curvature radius.

[0058] The first roller element portion 64a having the constant diameter herein has a sleeve area which has a very high coefficient of friction, on account of which the belt portion 3b can be guided through the two roller elements 62a and 62b in as slippage-free a manner as possible or with as little slippage as possible, respectively. Such a material can be rubber, for example. By contrast, the second roller element portion 64b having the variable diameter has a sleeve area which has a very low coefficient of friction so as to enable guiding of the semi-finished fibrous product by means of dynamic friction in this area. Such a sleeve area can be composed of stainless steel, for example.

[0059] In order for the process of varying the web height to be facilitated it is advantageous for the roller element pair 62 in the linear displacement that is transverse to the conveying direction to be simultaneously tilted or pivoted in the conveying direction or counter to the conveying direction (this in the exemplary embodiment of FIG. 2 being out of the illustration plane), so as to facilitate the vertically directed transportation of the belt portion 3b between the two roller elements 62a and 62b.

[0060] However, it is also conceivable for other roller element pairs of the system 10 to be embodied in a tilted or pivotable manner, specifically in the respective semi-finished fibrous product plane of the bearing semi-finished fibrous product part, so as to enable height-regulated guiding of the preform along the roller element pairs. To this end it is conceivable that the position of the preform is detected by means of a sensor, for example of a laser stripe sensor, and the roller element pairs depending on the position of the preform are actuated for pivoting or tilting such that a predefined nominal position of the preform is regulated during continuous preforming.

[0061] The fundamental construction of a roller element pair as is shown in FIG. 2 can also be applied to all other roller element pairs of the system 10 herein, such that the roller element pairs 51, 52, 53, and 61 are constructed according to the same principle as illustrated in FIG. 2.

[0062] FIG. 3 schematically shows the completely produced curved profiled preform 5 which has a first belt portion 3a as the outer belt, a second belt portion 3b as the inner belt, and an interdisposed web portion 4, wherein the web height h increases from the left to the right. A curved profiled preform of this type, having a complex cross section across the entire length, is producible in a process-reliable manner by way of the system according to the invention and the method according to the invention.

LIST OF REFERENCE SIGNS

[0063] 1 Planar semi-finished fibrous product

[0064] 2a First lateral portion

[0065] 2b Second lateral portion

[0066] 3a First belt portion

[0067] 3b Second belt portion

[0068] 4 Web portion

[0069] 5 Curved profiled preform

[0070] 10 System

[0071] 20 Fiber supply installation

[0072] 21 Semi-finished fibrous product roll

[0073] 22 Drive of the fiber supply installation

[0074] 23 Jockey roller

[0075] 30 Indexing installation

[0076] 31 Indexing roller

[0077] 40 Forming installation

[0078] 50 Shearing installation

[0079] 51 First roller element pair

[0080] 52 Second roller element pair

[0081] 53 Additional roller element pair

[0082] 55 Fiber angle sensor

[0083] 60 Cross-sectional modification installation

[0084] 61 First roller element pair

[0085] 62 Linearly displaceable second roller element pair

[0086] 70 Cutting installation

[0087] 80 Controller installation

[0088] 90 Belt webbing infeed installation

[0089] 91 Additional belt webbings

[0090] 62a, 62b Roller element of the linearly displaceable second roller element pair 62

[0091] 64a First roller element portion

[0092] 64b Second roller element portion