EP2903803A1

EP2903803A1 - Device for producing fibre preforms, which constitute in particular a preliminary stage during the production of fibre-reinforced plastic components

Info

Publication number: EP2903803A1
Application number: EP13765982.7A
Authority: EP
Inventors: Marco Göttinger; Sebastian Gierl; Michael Kaiser; Yannis GROHMANN
Original assignee: Audi AG; Voith Patent GmbH
Current assignee: Audi AG; Voith Patent GmbH
Priority date: 2012-10-05
Filing date: 2013-09-17
Publication date: 2015-08-12
Also published as: WO2014053305A1; DE102012218186A1

Abstract

The invention relates to a device for producing fibre preforms, which constitute in particular a preliminary stage during the production of fibre-reinforced plastic components. The device has a plurality of unwinding stations (1, 2, 3, 4) for providing a plurality of yarns or rovings or tapes, and a plurality of grippers (6, 7, 8, 15, 15', 15''), each of which is able to grip one or more yarns or rovings or tapes at the start thereof (20). Each gripper (6, 8, 15) can be moved back and forth on a path between a maximum position (12) and a pick-up position (11), and the pick-up position (11) is provided at a yarn transfer point (14) and is closer to the unwinding station (1, 2, 3, 4) than the maximum position (12). Each of the grippers (6, 7, 8, 15, 15', 15'') can be moved individually on paths which are substantially parallel to one another. The yarns or rovings or tapes can be tensioned in parallel, a first positioning element (24) is secured on each gripper (6, 7, 8, 15, 15', 15''), and at least one corresponding second positioning element (25) is provided for each first positioning element. The position of the gripper (6, 7, 8, 15, 15', 15'') can be fixed by the first and second positioning elements interlocking at a point along the path.

Description

Apparatus for the production of fiber preforms, which in particular constitute a precursor in the production of fiber-reinforced plastic components

The invention relates to an apparatus for the production of fiber preforms, which in particular constitute a precursor in the production of fiber-reinforced plastic components, the apparatus having a plurality of unwinding stations for providing a plurality of yarns or rovings or ribbons and a plurality of grippers, each one or more yarns or rovings or bands at its beginning, each gripper being reciprocally movable on a path between a maximum position and a pick-up position, and wherein the pick-up position is provided at a yarn transfer point and closer to the unwind station than the maximum position the grippers are each movable individually on substantially parallel paths, so that the yarns or rovings or bands can be clamped in parallel.

Fiber-reinforced plastic consists of matrix material and of fibers that are embedded in the matrix material and that provide, among other things, the tensile strength. Fiber-reinforced plastic is used especially for high in astetete components that should still be as light as possible. Since the fibers impart no strength in the transverse direction, the fibers must be aligned so that their longitudinal direction coincides as well as possible with the respective loading direction. To achieve this, the fibers often have to be laid in different directions. The better and more accurately the fiber layer is adapted to the load and the more uniformly the fibers are arranged, the better the component will be. For components made of fiber-reinforced plastic, there are numerous manufacturing processes. For the production of large numbers of well-applicable methods, however, there are currently only with rotationally symmetrical or plate- or strand-shaped components by winding or plate or extrusion. On the other hand, more complex 3-D structures can only be produced in a very complex manner, since producing the required fiber preforms is difficult, slow and expensive. High quality structures are usually made with continuous fibers. In many processes, fiber preforms are first produced corresponding to the desired three-dimensional component shape, so-called preforms, which predominantly consist of fibers which are often arranged one above the other in several layers in order to achieve the necessary fiber directions. Subsequently, the fiber preforms are then soaked or coated with the matrix material, pressed and cured or pressed and consolidated. Both for the production of the fiber preforms and for the impregnation and / or hardening or consolidation of the components molding tools can be used according to the desired component shape, or placed and pressed into the fiber preform or the component. So that the fiber preforms have sufficient dimensional stability for further processing, they are provided with small amounts of adhesive or binder and fixed after the three-dimensional draping, for example by drying or by heating and cooling. The fiber preforms are usually created by superimposing and fixing of prefabricated and pre-bonded flat semi-finished products. Such semi-finished products are for example tapes or fabrics, scrims or nonwovens in which a multiplicity of individual yarns or rovings are already woven, sewn or glued into a flat structure. A yarn is referred to when using so-called continuous fibers, ie when the fibers are unwound from a coil or a ball. Many yarns untwisted simultaneously from a spool or from a ball are called yarn bundles or rovings. The rovings can consist of up to several ten thousand single yarns, which are also called filaments. Often, a high proportion of manual activities is necessary. More complex shapes can not yet be produced by machine and in large numbers. Another possibility for producing fiber preforms for more complex components is automated fiber laying. In this case, narrow bundles of yarns or bundles of yarn bundles are guided back and forth by a fiber laying head over the molding tool, and deposited, pressed and fixed next to and above one another. For complex components, a complex robot-like control of the fiber laying head is necessary. Even with the use of two, three or even four fiber lay heads in parallel, the production speed is still relatively slow, as the heads often have to travel long distances and successive narrow fiber bundles are used. Furthermore, they have a very long and complicated yarn tracking from the creel to the multi-axis moving laying head. Such yarn tracking in hoses with special guide blades to prevent twisting of the rovings is shown for example in US 2008/0202691 A1.

The still unpublished application DE 10 2011 007018 of the applicant describes a device for the automatable production of fiber preforms with a plurality of parallel movable grippers for clamping and depositing fibers in a layer on a molding tool. The grippers are in this case on a guide device, e.g. attached to a pole, so that they can be freely cantilevered. For the production of larger components, however, a large travel is necessary. This leads either to a certain inaccuracy due to deflection and vibrations of the guide device or the guide device must be made correspondingly solid, which limits the traversing speed and thus the operating speed due to the weight or because of the inertia.

The object of the invention is to develop a corresponding device so that a higher accuracy in the manufacture of the fiber preforms is achieved and at the same time a great flexibility and high operating speed is possible. The object is achieved by a device with the features of claim 1. A first positioning element is fastened to each gripper and at least one corresponding second positioning element is provided for each first positioning element, wherein the position of the gripper can be fixed by interengaging the first and the second positioning element at a location along the path. The grippers are moved along the path by the guide device, which may be designed, for example, as a rod or carrier. With the aid of the first and second positioning elements, the grippers are precisely positioned at one position, so that the position of the gripper can be precisely predetermined without the need for complex control or programming or a highly precise and very rigid guide device. For this purpose, the positioning elements can each have a stop surface. The stop surface can serve both as a stop in the direction of the path, as well as in one or both spatial directions perpendicular to the path. The stop surface may for this purpose have a plurality of, for example stepped or angled or also conical abutment surfaces. The second positioning element can also be designed to be displaceable along the path of the gripper in order to be able to set different stop positions. By more precise fine adjustment, it may be sufficient if the grippers are positioned only slightly inaccurate by the guide device. The guide device can therefore be made lighter and easier. The guide device is connected to a drive in order to be able to move the gripper along its path. If necessary, stronger and therefore heavier grippers can be used without tolerance problems. Overall, the leadership of the gripper can be performed with more tolerance, which saves costs.

Since less complex control effort is necessary, not only can more parts be produced per unit time, but also the change from one component form to another is much faster and more flexible possible. In addition, the mechanical positioning significantly increases reliability given as it is achieved with control engineering or sensor controlled solutions at a reasonable cost.

The exact positioning of the yarns or rovings or ribbons in the gripper can be made more accurate. Likewise, the arrangement of the spanned yarns or rovings or bands or their location when depositing can be done more accurately. This makes it possible, very quickly and with little fiber material to produce high-strength and very load-adapted shaped fiber preforms.

A further advantage results if, for each first positioning element, a further, third positioning element is present, wherein the position of the gripper can be fixed by interengaging the first and the third positioning element at a further point along the path. As a result, the position of the grippers can be set more precisely at least at two points, for example when picking up the yarns or rovings or ribbons at the yarn transfer point and at a forming tool for depositing the yarns or rovings or ribbons.

The position can be determined particularly accurately if the position of the respective gripper in a spatial direction perpendicular to the path, preferably in both directions perpendicular to the path, can be determined in each case by the intermeshing of the first and the second or third positioning element. As a result, the gripper and thus the spanned yarn is positioned more precisely not only along the path but also transversely thereto.

An advantageous embodiment is such that each first positioning element has at least one elevation, in particular a conical or centering elevation, and that every second and / or third positioning element has a recess which fits in accordance with the elevation. As a result, the positioning elements engage with each other so that when moving together a centering on the desired position. An alternative embodiment provides that each second and / or third positioning element has at least one elevation, in particular a conical or centering elevation, and that each first positioning element has at least one recess corresponding to the elevation.

Positioning elements which each have a plurality of elevations or a plurality of depressions are also suitable for the embodiment according to the invention. In addition, both the first positioning element and the second and / or third positioning element can each have an elevation and a depression, which mutually engage one another when moving together. As a survey and matching well into consideration: Angular or cylindrical pins, preferably with chamfering at the top, and matching holes or guide rails with corresponding counterparts. In addition or as an alternative to the chamfering of the elevation, the respective depression can also have a chamfer in order to ensure secure engagement, even if the gripper is not quite exactly approached.

It can also be present for the positioning with respect to the two spatial directions transverse to the path two separate elevations and depressions on the respective positioning elements. One for one spatial direction and one for the other spatial direction. For example, each one wedge-shaped rib and a matching notch each transverse to the corresponding spatial direction.

Since the yarn transfer point is preferably located at the maximum position, as at the maximum extended guide device, it is particularly advantageous if the respective second or third positioning element are provided at the yarn transfer point. This increases the accuracy of clamping the yarns or rovings or ribbons in the pick-up position of the gripper.

Particularly advantageously, the invention can also be used for the devices described below. The spun yarns or rovings or ribbons may be laid down on a table or via a forming tool placed under the stretched yarns or rovings or ribbons. On the table or over the mold creates a position. For cutting one or more separators are provided which can separate the yarns or rovings or ribbons in the area of the yarn transfer points. After separation, another layer can be placed, for example, at a different angle.

The yarns or rovings or ribbons are preferably made of carbon, glass or aramid fibers. The yarns or rovings can be splayed on the way between the unwinding station and the yarn transfer point, so that they are neatly clamped next to each other. This can be done for example by multiple deflection around rollers or rods.

As fiber material also tissue or Gelegebänder can be clamped. In order to achieve a certain dimensional stability for the fiber preform, the fibers or rovings or ribbons may already contain binder material or binder material may be applied between the unwinding station and the yarn transfer point or near the pick-up position. The binder material can also be applied only to the unfolded or deposited layer. For example by spraying.

On the yarns or rovings or ribbons, the matrix material may also already be applied, which is then consolidated or cured after forming. In this case, the fiber preform already contains matrix material in not yet cured or not yet fully consolidated form.

The several unwinding stations can be designed, for example, as a so-called creel. The yarns or rovings can be drawn from bobbins or bobbins. Each yarn transfer point receives yarn or rovings from one or more unwind stations. At the coil or at the yarn transfer point or in between a device for Control or adjustment and / or means for measuring the yarn tension may be present.

The clamping width of the grippers is preferably 10 to 500 mm, particularly preferably 30 to 100 mm. As a result, the respective component contours can be reproduced sufficiently fine. Optionally, the grippers may also have different widths to map corresponding contours without undue effort. In order to be able to produce a useful surface for the production of fiber preforms while maintaining good flexibility of the device, it is advantageous if at least 5 grippers, preferably at least 10 grippers, more preferably at least 20 to a maximum of 40 grippers are present. As a result, more complex contours can be displayed well. With more than 40 grippers, however, the expenditure on equipment becomes too great.

The device according to the invention may preferably have a table, which is rotatable about an axis substantially perpendicular to the paths and which can be raised and lowered substantially perpendicular to the paths. By lifting the table can be brought, for example, in the plane of the spanned yarns so that they can be better placed on it. Turning the table allows you to place several layers at different fiber angles for a load-oriented production of the fiber preform, for example below +/- 30 ", +/- 45 °, +/- 60", +/- 90 " preferably rotatable by +/- 30 "to +/- 90".

In order to produce 3-dimensionally deformed fiber preforms, a first molding tool can be provided, which can be brought between the pick-up position and the maximum position of at least some grippers, in particular so that the spanned yarns or rovings or ribbons are thereby draped over the first molding tool , The first mold may for example be mounted on the table and raised above this and lowered and rotated. Especially with 3-dimensional forming with possibly high degree of deformation, it is important that each gripper different length of yarn can be pulled out with constant yarn tension. Here, the invention offers great advantages without excessive effort, especially since no complicated regulation is necessary. The constant yarn tension can reduce warping of the structure of the fiber preform.

In addition to the first forming tool, there may be one or more further forming tools which can be moved together with the first forming tool so as to reshape the spanned yarns or rovings or ribbons in a 3-dimensional manner. As a result, stronger transformations and a more accurate shape are possible. The further mold may be formed as a hood, which forms a counter-mold to the first mold and presses the fiber layer to this. The further shaping tools can also be designed as a plurality of punches or partial hoods, which press the fiber layer only at specific locations on the first molding tool, for example in concave areas or at edge transitions of the mold. The other molds can also be made to be movable in different directions and inclined relative to the vertical in order to be able to press the fiber layers of the desired shape correspondingly to the first mold. Again, the invention can be used particularly advantageous. In order to activate the binder material or to make the layers malleable, the first and / or one or more further molding tools can be heated. Likewise, however, the first and / or one or more further molding tools can also be cooled in order to re-solidify already preheated binder material during shaping. Furthermore, a heating device, in particular an IR radiator device or a heated plate, may be provided, which are the fibers or rovings or bands during or after clamping heated. As a result, binder material can be activated or the clamped layer can be made more deformable.

In order to increase the storage accuracy and thus to be able to produce better fiber preforms, it is advantageous to provide the respective second or third positioning element on the table or on the first mold. The first positioning elements can either be arranged so that they come into engagement with the second or third positioning element during a movement of the gripper on the first mold located between gripper and yarn transfer point. Or the first forming tools are mounted to engage the second or third positioning members upon movement of the first forming tool between the grippers and the yarn transferring stations, thus effecting accurate positioning of the grippers. In order to be able to keep the yarn tension constant or to be able to pull back excessively stretched yarn length, each gripper can be assigned at least one yarn storage device which is provided between unwinding station and yarn transfer point. The yarn storage device has at least two fixedly mounted deflection elements and at least one translational, in particular substantially vertically displaceably mounted tensioning roller between a first and a second end position, wherein the deflecting elements and the tensioning roller are looped by the yarns or rovings or belts so that the tensioning roller is arranged in the yarn path between the deflecting elements. By translationally freely displaceable it is understood that the tensioning roller is displaceable in a substantially rectilinear manner. For example, in a rail or a guide and without that a drive is provided. A damping or a certain friction or a certain holding force may nevertheless be present. By translational should also be understood even a slight curvature of the displacement. In this case, the tension roller has a first and a second end position, between which it is displaceable. The first end position is closer to the two deflecting elements than the second end position. The displacement is triggered by a short-term small change in the yarn tension, which acts against the weight of the tension roller or against a holding force, for example by a spring. Due to the displacement from the first end position in the direction of the second end position, the Garnlaufweg is extended between the two deflecting elements, so that run length is cached. The speed of the yarns or rovings or ribbons during this displacement at the outlet is smaller than at the inlet to the yarn storage device. In a shift from the second towards the first end position of the Garnlaufweg between the two deflection elements is shortened, the stored run length is reduced. During this shift, the speed at the outlet is greater than at the inlet.

Thus, a short-term decoupling or reversal of the speeds during unwinding and clamping by the gripper or during forming is possible. The decoupling of the speed can be used so that withdrawn by the gripper during clamping to beyond the mold addition pulled yarn and thus the yarn tension is kept constant, while the gripper is moved back towards the first mold until the first positioning with the on Mold or table-mounted positioning is engaged. The yarn storage device reacts without extra regulation on the externally given speeds or yarn tensions and thus compensates for temporary differences. The fixedly mounted deflection elements are, for example, rotatably mounted rollers or deflection rods.

By way of embodiments, further advantageous features of the invention will be explained with reference to the drawings. The features mentioned can not only be implemented advantageously in the illustrated combination, but also individually combined with each other.

Fig.1 - 4 preferred embodiment of a device according to the invention

Fig.1 when picking up the rovings (side view) Fig.2 when picking up the rovings (top view)

3 when mounting the rovings (top view)

Fig.4 when forming the rovings (side view)

Fig.5 detail representation for an embodiment of the positioning

6 shows a section of a device during clamping (top view)

7 shows a detail of a device when approaching the gripper to the first mold (top view). The figures are described in more detail below. The devices according to the invention shown in the figures are described for the processing of rovings. But they can be used in the same way for yarns or ribbons. The devices are suitable for carrying out the following method steps successively or partly parallel to each other:

- Providing the rovings and possibly the binder material

- Grasping the required rovings and possibly the binder material, while positioning the gripper by the positioning elements

- Clamping the required rovings by appropriate positioning of the gripper

Draping or depositing via a first molding tool and thereby approaching the gripper to the first molding tool with positioning of the gripper by positioning elements

- Forming with another mold

- Fix the layer of rovings

- Separation of the rovings in the area of the yarn transfer points

- Opening the molds

- Turning and / or passing a molding tool with the applied layer

Repetition of the procedure for the application of further layers in the same device or in one or more further devices according to the invention. As the fiber material for the yarns or rovings, fibers such as carbon (carbon), glass, or aramid or other fibers may be used. And as a mattress material for the fiber-reinforced plastic, for example, thermoplastic or thermosetting plastic comes into question. The binder material may be thermoplastic, thermoset or adhesive. It can either already be present as hybrid yarn or hybrid roving, ie individual fibers or yarns are made of binder material, or it can be spanned together with the rovings from the gripper or it is applied or sprayed onto the draped rovings.

FIGS. 1-4 show a preferred device according to the invention. In Fig. 1 and 2, the picking up of the rovings using the gripper is shown. Once in side view and once in plan view. The basic structure of the device is also recognizable. The provision of the yarns or rovings takes place via a multiplicity of unwinding stations 1, 2, 3, 4, in which the fiber material is provided in the form of bobbins or bundles of yarn (so-called bobbins) and which are arranged next to one another, behind one another or one above the other in several rows 1, 2 are arranged. The beginnings of the yarns or rovings 20 are shown schematically only in the respectively used area for the unwinding stations 3,4 used. All other beginnings are threaded to the corresponding yarn transfer points 14, so that they can be detected by the associated grippers in pick-up position 8. The location of the pick-up positions is marked with 1 1. Such a thing is also called a creel. On the other side of the device, the grippers 6 are shown in their maximum positions 12. The clamping width of a gripper is preferably slightly wider than the actual width of the rovings clamped by a gripper. Even if only equal width gripper are shown, of course, grippers with different widths are possible. The grippers do not necessarily have to have their maximum and pickup positions in line. The grippers are each coupled to a guide device 10. The guide device may be, for example, a rod or a carrier. The guide devices are connected to a drive system. In the apparatus shown are the Grippers parallel to each other, moved on linear, horizontal paths. They can also be moved individually to different positions.

The grippers 8 are in pick-up position and pick up the rovings at the yarn transfer point assigned to them by gripping their beginnings 20. In order to be able to position the gripper 8 as simply but accurately as possible when the guide device 10 is fully extended, a first positioning element on the gripper 8 and a second positioning element on the yarn transfer point 14 are present, which are in the pick-up position in the engagement 26.

Several unwinding stations 3, 4 can be combined into one group and assigned to a gripper 8. A gripper 8 can grab several rovings together. In any case, at least as many unwinding stations 3, 4 as gripper 8 should be provided. Each gripper 8 is assigned a yarn transfer point 14. Furthermore, there may be a binder material supply, which may for example be arranged between the rows of unwinding stations. The binder material can also be applied between the unwinding station and the yarn transfer point or on the mounted rovings. Between Abwickelstation 3,4 and yarn transfer point 14, a yarn storage device 13 is arranged. For each gripper 8, a separate yarn storage device 13 is provided, which can react depending on the respective take-off speed. The rovings are guided over two deflecting elements 9 and a tensioning roller 5 mounted between them and mounted in a translationally freely displaceable manner. The tension roller 5 is substantially vertically displaceable between a first end position 5a and a second end position 5b. This shortens or lengthens the Garnlaufweg. The displacement can be realized, for example, in rails or other guides. If, during clamping, more roving length at the yarn transfer point 14 is temporarily removed from the gripper 8 than is subsequently required during forming, then the tension roller 5 is raised. The memory empties. Is the clamping completed and will later the gripper to the mold moved up, so the tension roller 5 moves down. The rovings are withdrawn. The memory is refilled.

By the yarn storage device 13, the withdrawal speed at the yarn transfer point 14 can be decoupled from the conveying speed at the inlet briefly, which not only allows rewinding but also high clock rates with rapid changes in the take-off speed, without the conveying speed at the unwinding 3.4 must be changed , As a result, for example, a high distribution quality in width is still guaran teed. This is particularly advantageous if there is a yarn preparation unit (not shown here), such as a spreader or a binder application unit, between the unwinding station 3, 4 and the yarn storage device 13. Both the spreading and the binder application require the most uniform possible yarn speed.

In addition, a first mold 18 is shown on a lift table 17, wherein the mold 18 can be rotated on or with the lift table 17. Another mold 16, which is designed as a hood is shown in the down position so outside the paths of the gripper. The further mold 16 is not shown in plan view. And a corresponding movement or lowering device for the further mold 16 is not shown separately. The further mold can also be constructed in several parts, for example, of several stamps. On the first mold 18, an already deposited layer 23 of rovings is shown.

3 shows the device in plan view when mounting the rovings 21st The grippers are in an intermediate position 15, wherein the first positioning elements on the grippers 15 are now in engagement with the third positioning elements on the first forming tool 27. Depending on the shape, the grippers can also be moved to different intermediate positions, so that a close-contour clamping with little waste of expensive fiber material is possible. The grippers 15 span a layer of rovings simultaneously. By the Positioning elements, the position of the rovings is precisely determined so that a precise alignment and thus a high quality is achieved in the fiber preform.

Above the mounted rovings 21 a heating device, e.g. one or more IR emitters, be provided to heat any applied binder material or existing matrix material and thus to activate.

4 represents the device during the forming of the tensioned fiber layer. The lifting table 17 has moved upwards, so that the rovings 22 are draped over the first forming tool 18. The further forming tool 16 has moved together with the first forming tool 18, so that the rovings 22 are correspondingly shaped. The grippers 15 are held exactly in the desired position without complex control or sensors on the engagement 27 of the positioning.

During forming, a relatively large amount of additional yarn length is needed in a short time, especially in the case of more complicated 3-dimensional components, in order to keep the yarn tension constant and thus avoid a shift. The device according to the invention allows rapid closing and forming. The first mold 18 and / or the further mold 16 may be heated to heat binder material or already existing matrix material. Alternatively, the first mold 18 and / or the further mold 16 may also be cooled in order to cool already heated binder material and thus to fix the mold.

In Figure 5, an exemplary embodiment for the positioning elements is shown in side view. The first positioning element 24 is connected to the respective gripper 15 '. About a guide device 10 ', the gripper can be moved along its path. On the first mold 18 ', a second or third positioning element 25 is present. The first positioning element 24 has an elevation 28 which fits into the corresponding recess 29 on the second or third positioning element 25, whereby Approaching the gripper 15 'to the first mold 18' an exact mechanical fine adjustment of the position of the gripper 15 'relative to the first mold 18' takes place. If the elevation 28 is designed, for example, as a wedge strip and the depression 29 as a notch, an exact positioning in the direction of the path and perpendicular thereto in the vertical position is provided. If the elevation 28 as a cone and the recess 29 are designed to match, then the gripper 15 'is aligned even in the second spatial direction transverse to the path, ie in the transverse direction (into the plane of the page). Alternatively, the survey may also be designed as a pin, centering pin, guide rail or guide piece. The recess must be designed appropriately. Both elevation and indentation may have chamfers to facilitate the procedure of approaching. 6 and 7 show a detail of another device according to the invention. The spanned yarns or rovings or ribbons are not shown for clarity. 6, the grippers 7 are moved over the guide devices 10 'to span the gripped rovings over the first forming tool 18 ", and when the first forming tool 18" is then brought up between grippers 7 and yarn transfer points, the grippers will engage Meanwhile, the yarn storage devices provide for rewinding of the rovings and for constant yarn tension On the mold, the grippers 15 "are accurately aligned in position by the engagement 27 'of the positioning elements. By changing the mold can be quickly converted to the production of a fiber preform for another component. The new position of the grippers is determined mechanically by the positioning elements on the molding tool, without having to change over any control or regulation. LIST OF REFERENCE NUMBERS

1, 2 rows of unwinding stations

3, 4 unwinding stations in use

5 tension roller

5a first end position

5b second end position

6 row of grabs

7 row of grippers in clamping position

8 grippers in pick-up position

9 deflecting elements

10.10 ', 10 "guide device

1 1 Location of pick-up positions

12 position of maximum positions

13 row of yarn storage devices

14 row of yarn transfer points

15,15 ', 15 "gripper in intermediate position on the first mold

16 other mold

17 lift table

18, 18 ', 18 "first mold

19 more yarn storage device

20 beginnings of rovings

21 spanned rovings

22 draped rovings

23 already laid off rovings

24 first positioning element

25 second or third positioning element

26 engagement of the first in the second positioning element 27,27 'engagement of the first in the third positioning element 28 survey

29 deepening

Claims

claims

1 . Apparatus for the production of fiber preforms, which in particular constitute a precursor in the production of fiber-reinforced plastic components, the apparatus having a plurality of unwinding stations (1, 2, 3, 4) for the provision of a plurality of yarns or rovings or bands and a plurality of grippers (6, 7) , 8, 15, 15 ', 15 "), each of which can grip one or more yarns or rovings or ribbons at its beginning (20), each gripper (6, 8, 15) running on a path between one maximum position (12) and a pick-up position (1 1) is movable back and forth, and wherein the pick-up position (1 1) at a yarn transfer point (14) is provided and closer to the unwinding station (1, 2,3,4) is as the Maximum position (12), wherein the grippers (6,7,8,15,15 ', 15 ") are each individually movable on mutually substantially parallel paths, so that the yarns or rovings or bands can be clamped in parallel, characterized

a first positioning element (24) is fastened to each gripper (6, 7, 8, 15, 15 ', 15 "), and at least one corresponding second positioning element (25) is provided for each first positioning element, wherein the first and second meshing elements are intermeshed of the second positioning element at a location along the path, the position of the gripper (6,7,8,15,15 ', 15 ") can be fixed.

2. Apparatus according to claim 1

characterized,

in that there is a further, third positioning element (25) for each first positioning element (24), the position of the gripper (6, 7, 8, 15, 15) being joined at a further point along the path by intermeshing the first and the third positioning element ', 15 ") can be fixed.

3. Device according to claim 1 or 2

characterized,

that in each case by the intermeshing of the first (24) and the second or third (25) positioning the position of the respective gripper (6,7,8,15,15 ', 15 ") in a spatial direction perpendicular to the path, preferably in both spatial directions perpendicular to the path can be fixed.

4. Device according to one of the preceding claims

characterized,

in that each first positioning element (24) has at least one elevation (28), in particular a conical or centering elevation, and that every second and / or third positioning element (25) has a recess (29) corresponding to the elevation.

5. Device according to one of claims 1 to 3

characterized,

in that each second and / or third positioning element (25) has at least one elevation (28), in particular a conical or centering elevation, and that each first positioning element (24) has at least one recess (29) corresponding to the elevation.

6. Device according to one of the preceding claims

characterized,

in that respective second or third positioning elements (25) are provided at the yarn transfer point (14).

7. Device according to one of the preceding claims

characterized,

in that it comprises a table (17) which is rotatable about an axis substantially perpendicular to the paths and which can be raised and lowered substantially perpendicular to the paths.

8. Device according to one of the preceding claims

characterized,

a first forming tool (18, 18 ', 18 ") is present between the picking position (11) and the maximum position (12) of at least some grippers (6,7,8,15,15 ', 15 ") can be brought, in particular so that thereby the spanned yarns or rovings or ribbons (21) on the first mold (18,18', 18") are draped.

9. Apparatus according to claim 8

characterized,

in that one or more further forming tools (16) are present, which can be moved together with the first forming tool (18, 18 ', 18 ") in such a way that they reshape the clamped yarns or rovings or ribbons (21) in a 3-dimensional manner.

10. Apparatus according to claim 7 or 8

characterized,

in that respective second or third positioning elements (25) are provided on the table (17) or on the first molding tool (18, 18 ', 18 ").

1 1. Device according to one of the preceding claims

characterized,

at least 5 grippers (6, 7, 8, 15, 15 ', 15 "), preferably at least 10 grippers, more preferably at least 20 grippers and not more than 40 grippers are present.

12. Device according to one of the preceding claims

characterized,

in that each gripper (6, 7, 8, 15, 15 ', 15 ") is assigned at least one yarn storage device (13) which has at least two fixedly mounted deflection elements (9) and at least one translational, in particular substantially vertical between a first (5a ) and a second end position (5b) freely displaceably mounted tension roller (5), wherein the deflecting elements (9) and the tension roller (5) of the yarns or rovings or belts are looped so that the tension roller (5) in the yarn path between the Deflection elements (9) is arranged, and wherein the Garnspeichereinnchtung (13) between the unwinding station (1, 2,3,4) and yarn transfer point (14) is provided.