DE102013110186A1 - Apparatus and method for producing a semi-finished fiber product - Google Patents

Abstract

The present invention relates to a device (1) for producing a semi-finished fiber product (11), wherein a fiber strand (5) via pins (4) on a lower tool (2) is wound and optionally with an upper tool (7) of the fiber strand (5) pressed is cut and by cutting devices (8). The present invention further relates to a method for producing a semi-finished fiber product (11) with a device (1) according to the invention.

Description

The present invention relates to a device and a method for producing a semi-finished fiber product.

From the prior art it is known to produce motor vehicle components made of fiber composite material. For this purpose, for example, a roof skin, a hood or even motor vehicle structural components such as a B-pillar made of fiber composites. The fiber composite material consists on the one hand of a fiber material, usually glass fibers, carbon fibers but also aramid fibers, metal fibers or other fiber types, which are mixed with a matrix resin and thus form the fiber composite material. The matrix resin then cures, so that a predetermined shape, in which the fiber composite was pressed, is permanently maintained and the component receives its required strength or rigidity. The fiber material itself is usually provided in mat form or fabric shape and accordingly trimmed edge-side with a contour of the component to be produced with a supernatant. However, it is disadvantageous that a correspondingly high proportion of waste is obtained, which leads in particular to the use of high-quality and expensive fibers to a not inconsiderable increase in the cost of the production process.

Furthermore, from the DE 10 2010 015 199 A1 a method for producing a fiber blank is known, wherein initially a three-dimensionally shaped tool carrier is provided and then with the help of a laying head, a fiber bundle is placed respectively above the tool carrier and is fixed to the edge of the tool carrier. The fibers can then optionally be cut off at the edge after the fixing operation, whereupon a new laying process takes place. This method is optimized in relation to the waste produced during the production process, so that only a small production waste is obtained. However, the method is complicated to the extent that after each deposition process with the aid of a corresponding cutting device, the deposited fiber or the deposited fiber sheet must be severed and the fibers must be stored in three dimensions.

It is therefore an object of the present invention, starting from the prior art, to disclose an apparatus and a method with which it is possible to produce a fiber blank quickly and cost-efficiently.

The aforementioned object is achieved with a device for producing a semi-finished fiber product according to the features in claim 1.

The procedural part is further achieved according to the invention with a method for producing a semi-finished fiber product according to the features in claim 11.

Advantageous embodiments of the present invention are the subject of the respective dependent claims.

The apparatus for producing a semi-finished fiber product, wherein the device has a lower tool and are arranged on the lower tool pins for wrapping a fiber strand and forming a flat semi-finished fiber in an inner region of the lower tool, according to the invention is characterized in that the lower tool to the contour of the component to be produced is adapted and an upper tool is provided and cutting devices are provided on the lower tool and / or the upper tool, which trim the fiber strands.

In the context of the invention, a lower tool is accordingly produced corresponding to the outer contour, which is formed projecting beyond the outer contour of the component. On the lower tool then pins are attached, which protrude from the lower tool, which is then wound around the pins a fiber strand, so that in the interior of the lower tool, a flat semi-finished fiber product is formed for the later produced component. It can also fiber strands in the form of rovings or fiber bundles are wrapped around the pins. In this case, an individual winding pattern can be carried out for the component in each case, wherein the flat semi-finished fiber product can also be woven or sewn. In this way, it is initially possible to produce the semifinished fiber product with an endless fiber strand, wherein the actual depositing process or winding process can be carried out quickly and effectively, in particular with a laying head, very particularly preferably with a 2D laying head. The fact that the lower tool according to the invention is adapted to the contour of the component to be produced, which may mean that it is slightly over this protruding, excess fiber material, which would occur in the subsequent trimming as waste, largely reduced.

So that after the winding process, the fiber strands laid down to the flat semi-finished fiber products remain fixed in their relative position to each other, it is provided that the fiber strands are adhesively coupled together in the region of the clamping frame. In this case, an existing in the fiber strand binder or matrix resin can be activated, for example, due to thermal action. An additional or alternative solution is stitching.

Then, the invention further provides that cutting devices are provided on the lower tool itself and / or on the upper tool, with which it is possible to cut the fiber strands in a lowering and / or shortly after the lowering process between the lower tool and upper tool such that subsequently the finished semi-finished fiber can be removed from the frame and its further use is supplied. A trimming of each fiber strand after the deposition process, as is known from the prior art, is thereby avoided, so that is dispensed with a costly trimming operation, which is very time and cost-causing.

With the device according to the invention, it is possible to form two-dimensionally formed flat semifinished fiber products, as well as to lay or wrap these semi-finished fiber products essentially two-dimensionally and subsequently to preform three-dimensionally by the lowering process between the lower tool and the upper tool.

However, initially the winding process itself is particularly easy to carry out, the pins are formed as pins, which in particular have a decreasing in longitudinal section to a free end geometry. Thus, the pins or pins are thinner, narrower and / or smaller towards their free end, so that a particularly two-dimensionally movable laying head can lay the fiber strands particularly easy around the pins. Accidental miswinding is initially avoided due to the upward decreasing geometry so that the fiber strand is securely wrapped around the pin. As a result of the subsequent lowering process between the upper tool and the lower tool, the fiber strand is then tensioned again due to the cross-sectional geometry of the pin or pins increasing toward the lower tool.

Furthermore, particularly preferably, the pins have an abutment at their free end, in particular in the form of a cross-sectional enlargement. For example, the pins have a kind of ball head at their free end. This avoids that a already wound around the pin thread is moved by a further tensioning movement toward the free end of the pin or pins so that it slides over the free end and thus is no longer curious in his desired career ,

Furthermore, particularly preferably, the pins themselves are spring-mounted on the lower tool. This makes it possible that the pin yields slightly during the wrapping process, so that a wound fiber strand does not crack. Furthermore, it is made possible that upon contact with the two-dimensional position head, the pin yields slightly and thus again ensures that, when the trajectory of the laying head is not 100% executed, the fiber strand is still wound around the pin.

Furthermore, particularly preferably, the lower tool is projecting relative to the outer contour of the component to be produced in that it projects beyond the component by 1 to 50%, in particular by 1 to 30%, particularly preferably by 1 to 20% and very particularly preferably by 1 to 10%. This makes it possible to carry out the wrapping process particularly quickly and to provide the fiber blank such that in a three-dimensional subsequent shaping process for producing the fiber composite component lateral insertion of the fiber mat in the mold provides sufficient reserves, so that the semifinished fiber is not formed laterally too short and yet the accumulated waste or production waste is kept low.

Furthermore, particularly preferably, the lower tool and / or the upper tool are heated. Here, it is possible, in particular in the case of pre-impregnated fiber strands, to thermally activate the matrix resin present in the fiber strand and / or the adhesive by the thermal action, so that the fiber strands are wound around the pins and fixed relative to one another. Furthermore, particularly preferably, a non-stick coating is applied to the lower tool and / or the upper tool, so that the fibers do not adhere to the lower tool and / or the upper tool during subsequent removal and are therefore particularly easily detachable from them.

The cutting device according to the invention is further characterized in that each pin corresponding to a cutting device is assigned, so that each wound around the pin fiber strands are severed by the corresponding to the pin cutting device during the closing process of the lower tool and upper tool. The cutting device is for this purpose designed in particular as a cutting blade or cutting blade, wherein the cutting device itself is designed to be decreasing in particular towards its free end. This in turn ensures that in a lowering operation of the lower tool and upper tool to each other first, the cutting device with its decreasing or pointed end behind the fiber strands can be guided and then tensioned by the then increasing cross section of the fiber strand, so that it comes to a separation process with further retraction ,

According to the invention, however, it is also possible that the cutting devices are movable separately from the upper tool and lower tool and first the lower tool and the upper tool to fix the fiber strands to each other and then cut the cutting devices according to the fiber strands.

In particular, the pins are hollow and semi-open in cross-section. The cutting devices themselves then enter into the cavity and pass through the opening of the half-open cross section of the pin. Upon further retraction, the cutting device is then opposite the outer lateral surface of the pin, biases the fiber strand and ultimately cuts through it. For this purpose, the openings are directed in particular with respect to the lower tool to the outside, so that also a cutting tip or cutting edge of the cutting device is also directed outwards.

• – Bereitstellen eines an die Außenkontur des herzustellenden Bauteils angepassten Unterwerkzeuges,
• – Umwickeln der Stifte des Unterwerkzeuges mit einem Faserstrang, so dass auf dem Unterwerkzeug ein flächiges Faserhalbzeug ausgebildet wird,
• – Verkleben der Faserstränge untereinander im Bereich des Unterwerkzeuges und Beschneiden der Faserstränge,
• – Entnahme des Faserhalbzeuges.

The present invention further relates to a process for producing a semifinished fiber product, wherein a device having at least one of the aforementioned features is used for carrying out the process and the process according to the invention comprises the following process steps:

• Providing a lower tool adapted to the outer contour of the component to be produced,
• Wrapping the pins of the lower tool with a fiber strand, so that a flat semi-finished fiber product is formed on the lower tool,
• Bonding the fiber strands to one another in the area of the lower tool and trimming the fiber strands,
• - Removal of the semifinished fiber product.

To produce the semi-finished fiber product, it is thus possible to wind the lower tool with a winding head in such a way, in particular around the pins, that in the middle of a flat semi-finished fiber product is formed. The semifinished fiber product is then trimmed and between the upper tool and the lower tool, the fiber strands are fixed in position relative to each other so that the semi-finished fiber also retains the transport substantially a flat shape with the desired fiber strand orientation.

In particular, the fiber strands are pre-impregnated and are glued or sewn together between the lower tool and the upper tool. Alternatively, the fiber strands may also be pre-impregnated and are glued together by thermal action in the region of the lower tool. Alternatively or in addition, it is possible that the fiber strands are glued together by applying an adhesive in the region of the lower tool. As a result, the semifinished fiber product experiences a relative positional fixation of the fiber strands relative to one another in its edge region, so that the contours but also the planar fiber orientation are retained in a further transport process.

In the context of the invention, it is also possible that the flat fiber strands are also fixed in position to each other in the interior of the lower tool with a binder powder. In particular, in the case of a complex fiber strand orientation and / or interweaving of the fiber strands with one another, this is necessary.

Furthermore, it is possible according to the invention not only to provide a two-dimensional semi-finished fiber product, but also to produce a three-dimensionally preformed semi-finished fiber product. For this purpose, the lower tool has not only a two-dimensional design, but a three-dimensional design. First, however, the fiber strands are essentially two-dimensionally wound from one pin to the opposite pin. By subsequently pressing with the aid of the upper tool, the semi-finished fiber to be produced then receives a three-dimensionally formed precontouring.

Further features, characteristics and aspects of the present invention are the subject of the following description. Preferred embodiments are shown in the schematic figures. These are for easy understanding of the invention. Show it:

1 a perspective view of an inventive device with lower tool and upper tool,

2 a plan view of an inventive lower tool with wound around the pins fiber strand,

3a and b a pen each in a side view,

4 a spring-mounted pin according to the invention in a side view,

5a , b and c a device according to the invention in a side view in the open and closed state in various embodiments,

6a and b is a side view of a pin and a separator in various embodiments,

7a and b is a cross-sectional view through a pin according to the invention with cutting device and

8a and b an alternative embodiment of the device with upper tool and lower tool.

In the figures, the same reference numerals are used for the same or similar components, even if a repeated description is omitted for reasons of simplicity.

1 shows a perspective view of a device according to the invention 1 , Here is a lower tool shown below 2 shown, with circumferential at the edge 3 of the lower tool 2 pencils 4 are arranged. To the pins 4 is indicated a fiber strand 5 wrapped so that on an interior area 6 of the lower tool 2 a non-illustrated planar semi-finished fiber product is formed. The lower tool 2 itself is adapted with its outer contour to the contour of the component to be produced. The lower tool 2 Correspondingly assigned is an upper tool 7 , wherein on the upper tool 7 cutting devices 8th are arranged, here in the form of cutting knives. The one on the lower tool 2 discarded and around the pins 4 wound fiber strand 5 is thus by retracting the cutting device 8th in the pins 4 on each outer edge 9 cut. The embodiment variant shown here between lower tool 2 and upper tool 7 each has only one separation function. The lower tool 2 and upper tool 7 However, it can also be the wound fiber strand 5 Press accordingly in a gap.

2 shows a plan view of the device according to the invention 1 , where it is easy to see that the lower tool 2 relative to the outer contour of the component to be produced 10 formed on the edge protruding. On the lower tool 2 then are the pins 4 arranged, taking around the pins 4 the fiber strand 5 is wound, so that the flat semi-finished fiber 11 indoor 6 of the lower tool 2 is trained. A two-dimensional movable laying head 12 Wraps the fiber strand 5 around the pins 4 ,

So that the fiber strand 5 the pencils 4 not to their free end 13 slipped over or slip off of this, the free end is formed thickened, for example, by a in 3a shown ball head 14 or in 3b an illustrated cross-sectional enlargement at the free end 13 ,

So the pen 4 Furthermore, the fiber strand 5 on the one hand optimally tensioned, on the other hand a trajectory error of the laying head 12 balances, this is still particularly preferably resiliently mounted, which in principle 4 is shown.

Furthermore, it is then possible by lowering the upper tool 7 opposite the lower tool 2 around the pins 4 wound fiber strand 5 to compress and at the same time and / or slightly time-delayed pruning. This is in 5a , b and c shown in different variants, based on the image plane in each case above in the open state and below in the closed state. In 5a has the upper tool 7 cavities 15 on, leaving the over the lower tool 2 protruding pins 4 in the cavities 15 of the upper tool 7 during a lowering movement of the upper tool 7 retract. Furthermore, the cutting devices 8th in the upper tool 7 arranged so that during a lowering movement of the upper tool 7 the cutting devices 8th either on the pins 4 drive past and / or at least partially into the pins 4 retract while doing the to the lower tool 2 pressed fiber strand 5 Crop on the edge.

Alternatively, the fiber strand 5 in 5b around the pins 4 wrapped and is by a lowering movement of the upper tool 7 only trimmed, but not the fiber strand 5 again between upper tool 7 and lower tool 2 pressed.

5c shows a further alternative embodiment variant, wherein shown here, the fiber strand 5 on the pins 4 of the lower tool 2 is wound, and then by a lowering movement of the upper tool 7 towards the lower tool 2 the fiber strand 5 between lower tool 2 and upper tool 7 is pressed. Further, on the pins 4 of the lower tool 2 cutting devices 17 provided, which also in 6b is shown, so that the fiber strand 5 over the pins 4 down to the lower tool 2 is pressed and simultaneously by the cutting device 8th , which also to the lower tool 2 is increasingly formed, according to additionally tensioned and on a cutting edge 16 the cutting device 17 be separated.

Furthermore, in 6a the principle 5b shown in a cross-sectional view, so that the upper tool 7 also has an extension on which the cutting device 8th is attached, the extension also as a pen 4 can be trained. The cutting device 17 then moves to the actual pen 4 of the lower tool 2 down and comes with her cutting edge 16 between the wrapping of the fiber strand 5 at the pin 4 , tensions the fiber strand 5 and finally separates it from the outside.

The functional principle is also in again 7a and 7b shown in a plan view. 7a shows a pen 4 which is semi-open in the cross-sectional profile, in particular C-shaped. To the pen 4 around is the fiber strand 5 wound. In the opening 18 of the pen 4 then moves the cutter 17 and cuts on an outside around the pin 4 wound fiber strand 5 , This corresponds to an embodiment according to, for example, the 5a and b. Alternatively, it is possible according to 7b that the pen 4 directly a cutting device 17 as well as in 6b is shown, so that the fiber strand 5 , according to 7b , corresponding to 5c , Presentation above the pen 4 is wound and then onto the image plane of 7b pressed downward by lowering the upper tool 7 is pressed and then over the cutting device 17 is stripped and ultimately severed by this.

8a shows an alternative embodiment of the device according to the invention 1 comprising an upper tool 7 and a lower tool 2 , being on the lower tool 2 in turn, pins 4 are arranged and the pins 4 in each case a cutting device with cutting edge 16 as shown in 6b have. Again the fiber strand becomes 5 , here indicated to the pins 4 wound and then by a lowering of the upper tool 7 represented in 8b , so moved in the lowering A, so that the fiber strand 5 at the cutting edge 16 a cut 19 experiences. The upper tool 7 has openings 20 on, with the openings 20 to the outer edge 21 of the upper tool 7 each one slot 22 own so that the cutting device with its cutting edge 16 on further lowering of the upper tool 7 in the slot 22 is received positively and thereby the cutting process or separation process is completed.

LIST OF REFERENCE NUMBERS

1

contraption

2

lower tool

3

edge

4

pencils

5

tow

6

interior

7

upper tool

8th

cutter

9

outer edge

10

 component

11

 flat semi-finished fiber product

12

 laying head

13

free end too 4

14

 ball head

15

 cavity

16

 cutting edge

17

 cutter

18

 opening

19

 cut

20

 openings

21

 edge

22

 slot

A

section

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 102010015199 A1 [0003]

Claims (13)

Device for producing a semi-finished fiber product ( 11 ), the device ( 1 ) a lower tool ( 2 ) and on the lower tool ( 2 ) Pencils ( 4 ) for wrapping a fiber strand ( 5 ) for the formation of a flat semi-finished fiber product ( 11 ) in an interior area ( 6 ) of the lower tool ( 2 ) are arranged, characterized in that the lower tool ( 2 ) is adapted to the contour of the component to be produced and an upper tool ( 7 ) and cutting devices ( 8th . 17 ) on the lower tool ( 2 ) and / or the upper tool ( 7 ) are provided, the fiber strands ( 5 ) trimming. Device according to claim 1, characterized in that the pins ( 4 ) are formed as pins, in particular with a longitudinal section to the free end ( 13 ) decreasing geometry. Device according to claim 1 or 2, characterized in that the pins ( 4 ) at its free end ( 13 ) have an abutment, in particular in the form of a cross-sectional enlargement. Device according to one of the preceding claims, characterized in that the pins ( 4 ) are resiliently mounted. Device according to one of the preceding claims, characterized in that the lower tool ( 2 ) with respect to the outer contour of the component to be produced ( 10 ) by 1 to 50%, in particular 1 to 30% and particularly preferably 1 to 20%, very particularly preferably by 1 to 10%. Device according to one of the preceding claims, characterized in that the lower tool ( 2 ) and / or the upper tool ( 7 ) are heated. Device according to one of the preceding claims, characterized in that the lower tool ( 2 ) with the upper tool ( 7 ) positively by applying a clamping force on the intermediate fiber support ( 5 ) can be coupled together. Device according to one of the preceding claims, characterized in that each pin ( 4 ) a cutting device ( 8th . 17 ) is correspondingly associated, so that when closing lower tool ( 2 ) and upper tool ( 7 ) each around the pen ( 4 ) wound fiber strands ( 5 ) are severable. Device according to one of the preceding claims, characterized in that the cutting device ( 8th . 17 ) is a cutting blade, wherein the cutting device ( 8th . 17 ) in particular to its free end ( 13 ) is formed decreasing towards. Device according to one of the preceding claims, characterized in that the pins ( 4 ) in cross-section have a semi-open configuration, wherein the cutting device ( 8th ) when closing in the opening ( 18 ) of the pencil ( 4 ) is retractable, in particular the opening ( 18 ) relative to the lower tool ( 2 ) directed to the outside. Process for producing a semi-finished fiber product ( 11 ) by means of a device having the features of at least claim 1, characterized by the following method steps: - providing a component to be produced on the outer contour of the component ( 10 ) adapted lower tool ( 2 ), - wrapping the pins ( 4 ) of the lower tool ( 2 ) with a fiber strand ( 5 ), so that in the lower tool ( 2 ) a flat semi-finished fiber product ( 11 ), - coupling, in particular gluing, or sewing the fiber strands ( 5 ) with each other in the area of the lower tool ( 2 ) and trimming the fiber strands ( 5 ), - removal of the semifinished fiber product ( 11 ). Method according to claim 11, characterized in that the fiber strands ( 5 ) are pre-impregnated and by pressing between lower tool ( 2 ) and upper tool ( 7 ) or that the preimpregnated fiber strands ( 5 ) by thermal action in the area of the lower tool ( 2 ) or that the fiber strands ( 5 ) by applying an adhesive in the area of the lower tool ( 2 ) are glued together. Method according to claim 11 or 12, characterized in that the lower tool ( 2 ) has a three-dimensional design, wherein first the fiber strand ( 5 ) around the pins ( 4 ) of the lower tool ( 2 ) and when pressing the lower tool ( 2 ) with the upper tool ( 7 ) in the lower tool ( 2 ) formed flat semi-finished fiber products ( 11 ) is preformed three-dimensionally and in particular is fixed with a binder.

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