NL2037174B1 - Method of providing a cut-out product from a sheet - Google Patents

Abstract

Title: Method of providing a cut-out product from a sheet Abstract The invention relates to a method of providing a cut-out product from a sheet comprising a fibrous layer that is impregnated with a matrix material, comprising: - placing the sheet on a support surface, the sheet comprising a lower backing layer releasably supporting thereon the impregnated fibrous layer, - cutting through the thickness of the fibrous layer, forming a closed contour defining a target product, - not cutting through the backing layer along a shallow cut section of the contour, such that along the shallow cut section the backing layer is not cut through, and - lifting the target product away from the support surface, thus forming the cut-out product. Fig. 13

Description

P136780NL00

Title: Method of providing a cut-out product from a sheet

Technical Field

The invention generally relates to a method of providing a cut-out product from a sheet comprising a fibrous layer that is impregnated with a matrix material. An example of a flexible sheet comprising a matrix material is a composite sheet comprising fibers held in a resinous matrix material, e.g. as used in the aerospace or automotive industry.

The invention also relates to a cut-out product and to a device for placement of cut-out products formed from a sheet comprising a fibrous layer that is impregnated with a matrix material and a lower backing layer releasably supporting the impregnated fibrous layer.

Background

Products may be cut out from a sheet with a cutting device, in particular a numerically controlled cutting device, e.g. a laser cutter, a jet cutter or a knife cutter. The sheets are typically in a flat, planar orientation when the cutting device is controlled to make product cut-outs in the sheet.

As sheets are typically stored rolled up on a roll, the sheet material may need to be uncoiled form the roll and possibly flattened before cutting.

The product cut-outs may be made in the sheet by cutting the full contour of the cut-out product, e.g. an inner and outer contour. However, the contour of a product cut-out may also be partially formed by an uncut boundary of the sheet. The cut for the product cut-out may be made as a continuous cut but may also be built up as an aggregate of several cuts. A first portion of the cut of the contour of a cut-out product may be cut at a first cutting stage, e.g. when cutting a part of the contour of an adjacent product cut-out, and a second portion of the cut of the contour of a product cut-out may be cut at a second cutting stage, e.g. when cutting a remaining part of the contour of the product cut-out.

Typically, the use of sheet material may be optimized by nesting product cut-outs in the sheet, especially when the sheet material is relatively expensive. The portion of the sheet that remains after removal of the product cut-outs from the sheet is called the skeleton. Preferably the surface area of the skeleton is minimized, as it often needs to be scrapped.

The product cut-outs may be final products or unfinished products that require subsequent production steps such as kitting, layup in a mould and consolidation. For instance, layered unfinished product cut-outs may be consolidated by subjecting them to heat and/or pressure to form a consolidated final or intermediate product, in particular a high strength, low weight product for use in demanding applications, e.g. structural parts for the aerospace industry. Product cut-outs in a sheet may each be identical, but may also differ, e.g. having different shapes and/or sizes.

In WO 2021/154081, a method is described for the automatic removal of product cut-outs from sheets using a number of retractable actuators having electrostatic or suction grippers, for gripping of the product, providing a rapid and cost-effective method.

The challenge with automatically placing a cut out product that is formed of a fibrous layer that is impregnated with a material having a predefined tack, such as a thermoset resin, is to remove the backing layer that may comprise paper, protective foil or laminates of paper and foil. The fibres and uncured thermoset resin (which may comprise an epoxy, polyester / cyanate ester/BMI and the like) are sticky since the resin is still in fluid form. The resin’s stickiness enables layup and forming end products made by stacking multiple layers, wherein the tack helps the layers in the laminate to properly bond together. The tack of the impregnated layer depends on temperature. The cut-out products are processed typically in a cleanroom with constant temperature. Using local heating, tack can be increased, for instance after placing stacked impregnated layers in a mould.

By selective cooling, tack goes down or becomes zero and eases handling of the impregnated layers.

It 1s an object to provide a method, a device and a cut-out product that allow rapid and accurate production and placement of cut-out products comprising a pre-impregnated fibrous layer. It is in particular an object to provide a method for forming and handling a cut-out product comprising a pre-impregnated layer for use in an automated lay-up process for producing composite materials.

Summary

Hereto the method according to the invention comprises: - placing the sheet on a support surface, the sheet comprising a lower backing layer releasably supporting thereon the impregnated fibrous layer, - cutting through the thickness of the fibrous layer, forming a closed contour defining a target product, - not cutting through the backing layer along a shallow cut section of the contour, such that along the shallow cut section the backing layer is not cut through, and - lifting the target product away from the support surface, thus forming the cut-out product.

By forming a shallow cut through the fibrous layer, the backing layer has a part that extends laterally beyond the perimeter of the fibrous layer. This allows versatile handling of the cut-out product. The backing layer may remain an integral layer that stays attached to the support surface upon lifting of the fibrous layer. Alternatively, the backing layer may be partially lifted from the support surface together with the fibrous layer until a peeling force is created. Alternatively, the peeling of the fibrous layer from the backing layer may be increased by introducing a sideways or rotating movement of the fibrous layer, or by applying vibration. The backing layer can also be released completely from the support surface and lifted and buffered together with the fibrous layer while forming a protruding tab.

The perimeter of the fibrous layer of the cut-out product may be formed partly by an edge of the sheet of fibrous material. Placing the cut-out product close to the edge of the fibrous sheet makes efficient use of the fibrous material. Alternatively, the cut-out product can be formed at a distance from the edges of the sheet of fibrous material and the cut through the fibrous layer may extend along a closed contour.

The cut-out product may be lifted by a manual operation, or via a robotic actuator and can be placed in a buffer or on laminating table, for instance on a stack of fibrous layers for forming a composite material.

The cut through the fibrous layer may be perpendicular to the surface of the layer or may extend at an angle to the surface.

A top backing layer may be placed over the fibrous layer and can be cut together with the underlying fibrous layer along the shallow cut section.

Alternatively, the top backing layer may in a first step be cut along a shallow section and then be removed from the underlying fibrous layer, which in a subsequent step is provided with a further shallow cut section.

A method according to the invention may comprise forming the shallow cut section extending along the entire contour, wherein the backing layer upon lifting of the fibrous layer-remains on the contact surface, the target product upon release of the fibrous layer from the backing layer forming the cut-out product.

The bottom backing layer remains on the support surface upon lifting of the impregnated fibrous layer. In order to overcome the tack between the backing layer and the fibrous layer, a vacuum may be applied to the backing layer through the support surface, or a belt material may be used as a support surface that creates adhesion to the backing layer.

On the fibrous layer, a top backing layer may be situated, which can be removed prior to cutting through the fibrous layer.

The removal of the top backing layer may be effected by providing a fist shallow cut in the top layer forming a closed contour, and peeling away the top backing layer material. Next, the underlying fibrous layer can be cut from the sheet and lifted from the support. Alternatively, the top backing 5 layer is cut together with the fibrous layer below. The actuator then picks up the fibrous layer via the top backing layer. The top backing layer prevents the actuator from coming into direct contact with the impregnated fibrous layer. The actuator may place the cut-out products in a buffer stack, where the top backing layer prevents adhesion of the stacked layers.

The material of the backing layers may comprise foil and/or paper.

A plastic foil can be used, or a paper that is covered with a release material.

The backing layers protect the composite material and for instance prevent contamination as a consequence of manual handling to be transferred to the fibrous material, which is not good for adhesion of the layers when combined into a composite structure. Also, when the impregnated fibrous material is put on a roll, without a protective foil the material would stick to itself. Rolls of material can be supplied with a 1 or 2-sided protection. A plastic foil can stretch, paper much less. So, for laminating, typically the paper backing layer is removed whereas a foil backing layer can stay on for draping and is only removed when the ply is the right 3D form. In the method according to the disclosure, the laminating process is 2-step: first multiple layers are stacked in a flat configuration to make a full layup, and are then formed into a 3D shape, for example in a press or in a die. It is also possible to use as an actuator a pick & place end-effector that can drape the fibrous layer directly into a 3D shape, or to manually layup the plies into a mould.

In a method according to the disclosure, the shallow cut section is provided along a first length of the contour, the backing layer being cut through along a deep cut section of the contour extending along a second length, the method comprising lifting of the fibrous layer and the backing layer away from the support surface so that a downward pulling force is exerted on the backing layer and the fibrous layer is separated from the backing layer, while leaving the backing layer material attached along the shallow cut section, thus forming the cut out product.

A complication that may occur when providing a shallow cut through the fibers along a closed contour, is that a sticky ply needs to be contacted by the actuator and lifted in a vertical direction away from the backing layer. If the surface area is large, the fibrous layer may not release from the backing layer and both layers may be pulled from the cutter bed. In order to obtain a peeling motion, a part of the contour is cut through all layers and a part of the contour is cut with a shallow cut that does not go into the lower backing layer. The lower backing layer remains attached to adjacent backing layer material at the position of the shallow cut. When this position is in a corner of the target product, during lifting of the ply a peeling motion will occur. Once initiated, it’s easy to separate the full ply of the target product by continued peeling upon completion of the lifting motion. When the actuator moves in the vertical direction, the peeling will occur as a consequence of the downward force that is exerted on the backing layer of the target product by the part of the backing layer that remains on the support surface and is connected to the skeleton. A horizontal component in the direction of movement of the actuator can enhance the peeling effect. Also, a sudden movement, such as a jolt, can improve the peeling. The exact position of the shallow cut will depend on the shape of the target product.

Depending on the size of the cut-out product, certain shapes can be picked up with a shallow cut extending along the whole contour, leaving the backing layer on the support surface without it being lifted. This is a faster action because making a combination of a shallow and a deep cut section of the contour may require an interchange of cutter knives, which can delay the method.

A method according to the disclosure may comprise providing a deep cut section along a first length of the contour , the shallow cut section extending along a second length of the contour between a starting position and an end position, wherein the backing layer is cut through along a tab contour section extending from the starting position to the end position in a transverse direction outside of the first length of the contour, forming a backing layer tab, the method comprising lifting of the fibrous layer and the backing layer away from the support surface, thus forming the cut-out product having , transporting the product to a removal member, contacting the backing layer tab with the removal member and separating the fibrous layer away from the backing layer.

The plies of fibrous layer and backing layer have a perimeter that extends along a contour having a protruding part, lip or tab. At the position of the tab, only the fibrous layer is cut. The backing layer can be effectively removed by gripping the cut-out product by the tab via a robot gripper or a mechanical gripper and peeling away the backing layer. After peeling, the fibrous layer at the position of the tab remains attached to the backing layer.

The fibrous layer may be placed in contact with a further fibrous layer, followed by pulling off the backing layer while the further fibrous layer exerts an attractive force (tack) on the fibrous layer.

An effective and efficient handling of the cut-out product is achieved by first placing the ply on a laminate of fibrous layers and using the sticking of the ply to the laminate to peel off the backing layer, which is now on top. An advantage of this method is that the composite material of the impregnated fibrous layer is separated from the actuator (end-effector) by the backing layer, so that contamination of the actuator is avoided. The protruding lip of the backing layer helps in creating a peeling motion when the backing is gripped at the position of the tab and moved away from the fibrous layer. Compared to the whole surface of the fibrous layer that sticks to the laminate, the peeling initiation at the protruding lip requires a relatively small force.

A peeling motion can also be effected by an actuator, such as described in WO 2021/154081 that was filed in the name of the applicant, for example using the compliance in the grippers of the actuator or activating multiple grippers in the actuator in a snake-type way.

The fibrous layer and the backing layer may be lowered in temperature for separating the fibrous layer from the backing layer.

Lowering of the temperature can decrease the tack and facilitate removal of the backing layer.

The target product may be lifted by the actuator in a direction that is at an angle of less than 90 degrees to the surface of the backing layer.

This improves the peeling effect.

In an embodiment, the cut-out product is placed on a stack and/or in a mould. After removal of the backing layer, the cut-out product can be combined in a lamination step with further fibrous layers, without further buffering.

The cut-out product may prior to placement in the mould be combined in a stack of similar cut-out products.

A method of providing a cut-out product may comprise forming two or more of a cut-out product having a shallow cut extending along a closed contour without a cut through the backing layer, a cut-out product having a partially cut-through backing layer and a cut-out product having a tab.

A cut-out product according to the disclosure comprises a fibrous layer that is impregnated with a matrix material supported on a backing layer, the overlying backing layer and the fibrous layer comprising a common contour having an outwardly extending tab where the contour extends in a transverse direction from a starting position to an end position, the fibrous layer being provided with a shallow cut section, extending from the starting position to the end position in a direction that is transversely oriented with respect to the tab.

A device for placement of cut-out products formed from a sheet comprising a fibrous layer that is impregnated with a matrix material and a lower backing layer releasably supporting the impregnated fibrous layer, comprises: - a cutting station adapted for forming a cut out-product, - an end effector having a gripper adapted for picking up the cut- out product and removing the backing layer from the fibrous layer, and - alaminating surface for receiving cut-out products, the end effector being adapted for placing the fibrous layer on the laminating table.

The cutting station may be adapted for forming a cut-out product having a tab, the device comprising a tab gripping unit adapted for gripping the tab of the cut-out product while the fibrous layer is contacted by the gripper of the end effector, the tab gripping unit and the end effector being movable relative to one another for peeling away the fibrous layer from the backing layer.

Brief Description of the Drawings

Embodiments of a method and device according to the disclosure will, by way of non-limiting example, be explained in detail with reference to the accompanying drawings. In the drawings:

Fig. 1 shows a perspective view of a device for forming cut-out products from a sheet of impregnated fibrous material,

Fig. 2 shows a top view of the device of fig. 1,

Fig. 3 shows an end-effector comprising a number of grippers,

Figs. 4a-4c show a side view and two top views, respectively of a method of forming a shallow cut contour in the fibrous layer,

Fig. 5 shows lifting of the fibrous layer of figs. 4a-4c while leaving the backing layer on the support,

Fig. 6 shows a method wherein the fibrous layer is situated below a top backing layer,

Fig. 7 shows lifting of the fibrous layer of fig. 6 via the top backing layer,

Fig. 8 shows cutting though the top backing layer along a shallow cut contour,

Fig. 9 shows removing of the top backing layer prior to providing a shallow cut contour in the fibrous layer,

Figs. 10a-10c show a side view and two top views respectively of a method of forming a contour in the fibrous layer that partially extends through the backing layer,

Fig. 11 shows lifting of the fibrous layer and the backing layer of figs. 10a-10c,

Figs. 12a and 12b show a side view and a top view respectively of a method of forming a tab on the cut-out product,

Figs. 13a and 13b show a cut-out product having a tab with and without the fibrous layer, respectively,

Fig. 14 shows a device for forming and automatic placement of cut- outs of pre-impregnated sheets of fibers, and

Fig. 15 shows a gripper device for clamping a tab during removal of the backing layer of a cut-out product.

Detailed Description

It should be noted that the figures are merely schematic representations of preferred embodiments of invention. In the figures, identical or corresponding parts are represented with the same reference numerals.

Referring to Figs. 1-2, a ply sorting device 1 according to a first embodiment of the invention is discussed. The ply sorting device 1 works in tandem with a cutter 2.

The material for the plies 3 is supplied as a sheet 4 of fiber material. The fiber material may be carbon fiber but may also be or comprise other type of fiber material, e.g. glass fiber or aramid fiber. The fiber material may have woven, or non-woven strands of fibers. The strands of fibers typically each have a single orientation. Preferably, the fibers in the material are parallel unidirectional, non-woven fiber strands. The fiber material may be impregnated with a resin. The resin material may be thermosetting or thermoplastic material, and in the finished product forms a matrix material. The resin may typically be uncured, e.g. in case of a thermosetting material. The resin may be sticky, e.g. in case of uncured resin. The plies 3 in this example are unfinished products: they are to be placed in layers and subjected to heat and pressure to form a product.

Because they are unfinished, the plies 3 cut from the sheet 4 of resin impregnated material are delicate and should be handled with care to prevent loss of integrity, and to prevent contamination. The impregnated fiber material may be provided with a protective layer, e.g. a top or bottom backing that is to be removed when the plies 3 are put in the mould. Sharp folding and exertion of (planar) force on the plies 3 is to be prevented. In order to ensure this, the plies 3 are preferably picked, moved and stored in a planar orientation. Due to limited shelf life of the resin as unfinished product, after cutting the plies 3 should be processed to products fairly quickly. Also, prolonged storage of plies 3 or sets of plies 3 is better avoided.

Referring to Figs. 1 and 2, the sheet of material is typically provided on a roll, which is stored in a protective packaging. After removal of the packaging, the sheet 4 is unrolled from the roll at a roll supply 5 and is placed on a flat conveyor belt 6 of a cutter 2. The cutter 2 typically is a numerically controlled X-Y knife, laser or jet cutting machine. The cutter 2 cuts plies 3 of different geometries. Plies 3 of different geometries may together make up a set to be used for moulding of a composite product. A set may typically comprise plies 3 of different size and shape but may comprise or even consist of plies 3 of the same geometry. A composite product may itself be comprised of several sets of plies 3. To optimize the use of the sheet material, a cutting file is produced by nesting of the plies 3 of several sets.

These sets may each be identical but may also differ. For example, different sets corresponding to smaller and larger products may be nested on the sheet 4 to optimize use of the sheet material. The output of the cutter 2 is thus a sheet 4 with cut-outs for plies 3, which is transported from the cutter 2 on a flat conveyor belt 6 to a pickup plane 7. In the example of Fig. 1 this 1s done by an unloading conveyor 8 connected to a sorting conveyor 9 at the same level. In this case, the unloading conveyor 8 defines a flat pickup plane 7 in which the cut sheet 4 lies. The plies 3 may be picked as cut-outs from the moving sheet on the sorting conveyor 9.

Due to the nesting, the plies 3 are typically not in an order so that subsequent plies 3 can be picked from the sheet 4 to form a set. For example, a ply 3 for a first set may come first, followed by another ply 3 for a second set.

In order to accommodate for this, a ply sorting device 1 is provided.

The ply sorting device 1 comprises a picker 10 and a buffer 11. In this example, the picker 10 is arranged to pick planar plies 3 of cut resin impregnated fiber material and move them to the buffer 11 in substantially planar orientation. The picker 10 is in the example of Fig. 1 embodied as a robotic arm, carrying a gripper head 12. Instead of a robotic arm, another type of moving device for the gripper head 12 may be provided, e.g. a simple rail with a movable carriage for the gripper head. Referring to Fig. 3, the gripper head 12 of the picker 10 may comprise a plurality of gripper organs 13 arranged in a gripper plane 14 of the gripper head 12, e.g. suction cups.

When picking a ply 3, a select group of gripper organs 13 from the plurality of gripper organs 13 arranged in the gripper plane 14 on the picker 10 is actuated by a controller 15 depending on the geometry of the ply 3 to be picked. While picking a ply 3, the occurrence of trailing of material from a picker 10 may be detected. For this, a detection plane may be arranged parallel to the pickup plane 7, e.g. a light screen, to detect any material extending between the pickup plane 7 and the gripper plane 14.

The buffer 11 comprises a plurality of substantially planar supports 16 each arranged to receive plies 3 from the picker 10 and to support the plies 3 in planar orientation in a stack.

Based on the data in the cutting file, the controller 15 arranges that the planar plies 3 of cut fiber material of differing geometries are subsequently picked by the picker 10 and are each moved in substantially planar orientation to a selected one of a plurality of supports 16 of the buffer 11. The controller 15 is in communication with the cutter 2 and the sorting conveyor 9. The controller 15 can use the data of the cutting file to locate the various plies 3, and to select the support where a set 15 collected to which the ply 3 is to be added. At the supports 16, the plies 3 are received in a planar orientation to become part of a stacked set of plies 3. In accordance with the invention, the completion of sets in the supports 16 of the buffer 11 1s used as a boundary condition in the nesting of the plies 3 in the sheet 4.

During nesting, account is taken of the available space at the supports 16 in the buffer 11. For example, if for all supports 16 plies 3 have been cut, and a set at a particular support lacks one ply 3 to be completed, that ply 3 is included next in the nesting of the cutting file with preference over another ply 3 with which a closer nesting may be achieved so that a support may be freed up sooner.

The planar supports 16 are movably arranged relative to each other to receive the plies 3. The supports 16 can be moved from a storage position in which they have a covering arrangement that prevents receiving of plies 3, to a receiving position that allows receiving of plies 3. Such a covering arrangement saves space, and prevents contamination due to sheltering. By spacing the supports 16 perpendicular to their plane, the covering arrangement may be facilitated. In this embodiment, the supports 16 are arranged to be movable perpendicular to their plane. The shelves of the buffer 11 are embodied as trays, so that the plies 3 of the set may be supported in a protected trough. The shelves are placed in a column and are liftably mounted to a frame transversely to the longitudinal direction of the shelves. The shelves are liftably mounted with a variable interspace to accommodate the picker 10 between shelves.

Fig. 4a shows a sheet 20 that is supported on a support surface 21.

The sheet 20 comprises an impregnated fibrous layer 22 and a backing layer 23. The support surface 21 may exert a downward force on the backing layer 23, for instance by means of a perforated surface and a vacuum source (not shown). The fibrous layer 22 has been cut through its thickness with a cutting device 24 along a contour 25 that defines a target product 26. As can be seen in fig. 4b, a closed contour 25 is formed by a shallow cut, indicated by the dashed line, that does not extend through the backing layer 23 and that is situated at a distance from the perimeter 27 of the sheet 20. As can be seen in fig. 4c, the contour 25 of the target product 26 can be formed partly by shallow cut section 28 and partly by the edge 29 of the sheet 20.

Fig. 5 shows the cut-out product 30 that is formed by a cut-out part of the impregnated fibrous layer 22, being lifted in an upward direction by an actuator 31, so that the cut-out product 30 is released from the backing layer 23. The actuator 31 may move in a direction parallel to the plane of the sheet 20 in order to enhance the peeling force on the target product 26 when it 1s released from the backing layer 23.

Fig. 6 shows an embodiment in which a top backing layer 33 is placed on the fibrous layer 22. The cutting device 24 cuts through the top backing layer 33 and through the fibrous layer 22, along the contour 25, forming a shallow cut that does not extend through the backing layer 23. As can be seen in fig. 7, the cut-out product 30 that is lifted by the actuator 31 away from the backing layer 23 includes a top backing layer part 33’, which prevents the actuator 31 from coming into contact with the impregnated fibers, and a fibrous layer part 22’.

Fig. 8 shows a top backing layer 33 that in a first step is provided with a cut along a contour 25, and that is removed from the fibrous layer 22 as shown in fig. 9. In a next step, the fibrous layer 22 in fig. 9 can be cut and peeled from the bottom backing layer 23 by the actuator 31 in the manner that has been shown in fig. 5.

Fig.10a shows an embodiment in which the contour 25 has a deep cut section 35 extending through the fibrous layer 22 and through the underlying backing layer 23, and a shallow cut section 36, indicated by the dashed line, extending through the fibrous layer 22 only. In the embodiment of fig. 10b, the shallow cut section 36 extends along a short side of the contour 25. In the embodiment of fig. 10c, the shallow cut section 36 extends near a corner of the contour 25, improving the peeling action, upon vertically lifting the fibrous layer 22 away from the backing surface 21, as shown in fig. 11.

In fig. 11 it is shown that upon upward movement of the actuator 31, a peeling action is initiated in which the fibrous layer 22’ is released from the backing layer 23 in the region of the shallow cut section 36.

In the embodiment of fig. 12a, the contour 25 comprises a deep cut section 35 and a shallow cut section 36. The deep cut section forms a sideways protruding tab 41 having a tab section 40 that extends between points 38 and 39 of the deep cut section 35. The shallow cut section 35 through the fibrous layer 22 together with the deep cut section 35 defines the target product 26.

Upon lifting the target product 26, as shown in fig. 13, the fibrous layer 42 overlying he tab 41 is lifted together with the fibrous layer 22 forming the cut-out product 30. For removal of the backing layer 23’ from the fibrous layer 22°, the tab 41 may be gripped and the backing layer and fibrous layer 42 can be peeled away from the fibrous layer 22’.

Fig. 13a shows a plan view of a cut-out product 45 having a tab 49 showing the layers of fibrous material 46 and 47 that are separated by shallow cut 48. Fig. 13b shows the backing layer 50 after peeling away the fibrous layer 46. At the tab 49, a small part of fibrous layer 47 remains attached to the backing layer 50.

Fig. 14 shows a machine 60 for the automatic placement of cut-outs 61 from a pre-impregnated sheet of fibers. The sheet comprises a pre- impregnated fibrous layer that is placed between a top backing layer and a bottom backing layer and that is unwound from a roll 62. Before the bottom backing layer is placed on the transport conveyor 64, the top backing layer is removed and is stored on a roll 63.

A cutter 65 cuts through the impregnated fibrous layer and may cut through the bottom backing layer, to form cut-outs 61, that are picked up by a robot 66 and end effector 67. For cut-outs 61 that are formed by the cutter 65 with a tab as shown in figures 10-13, the end effector 67 having grippers 73, transports the cut-outs 61 to a table 72 near a gripper 68 that grips the protruding tab of the cut-out to remove the backing layer from the fibrous layer. Thereafter, the robot 66 can place the fibrous layer on a laminating table 69 to be combined with other fibrous layers into a stack.

Alternatively, the cut-outs 61 can be placed in a buffer 70 prior to removal of the backing layer and be retrieved from the buffer to be combined at the laminating table 72 at a later stage.

Fig. 15 schematically shows a clamping device 68 that engages with the tab 49 of a cut-out 45 on the table 72. The grippers 73 of the end effector 67 pull the layer of fibrous material 46 upward so that it is peeled away from the backing layer 50, that remains on the table 72, together with the fibrous material overlying the tab 49.

Claims (17)

Conclusions A method for manufacturing a cut-out product from a sheet comprising a fibrous layer impregnated with a matrix material, comprising: - placing the sheet on a support surface, the sheet comprising a lower support layer releasably carrying the impregnated fibrous layer thereon, - cutting the fibrous layer to form a closed contour defining a target product, - not cutting the support layer along a shallow cut portion of the contour, such that the support layer is not cut along the shallow cut portion, and - lifting the target product away from the support surface to form the cut-out product. The method of claim 1, wherein the target product is engaged via an actuator that lifts the target product. A method according to claim 1 or 2, wherein the shallow cutting portion extends along the entire contour, wherein the support layer remains on the contact surface after lifting the fiber layer and the target product forms the cut-out product after releasing the fiber layer from the support layer. The method of claim 3, wherein a top support layer overlies the fibrous layer, and the method comprises removing the top support layer before cutting the fibrous layer. 5. The method of claim 3, wherein the top support layer lies on the fiber layer and the top support layer remains attached to the fiber layer after lifting by the actuator. 6. The method of claim 1 or 2, wherein the shallow cut portion extends along a first length of the contour, the backing layer is cut along a deep cut portion of the contour extending along a second length, the method comprising lifting the fibrous layer and the backing layer from the support surface to apply a downward tensile force to the backing layer and separate the fibrous layer from the backing layer while retaining the backing layer material along the shallow cut portion, thereby forming the cut product. A method according to claim 1 or 2, wherein a deep cut portion is provided along a first length of the contour, the shallow cut portion extending along a second length of the contour between a starting position and an end position, the backing layer being cut along a lip contour section extending from the starting position to the end position in a transverse direction outward from the first length of the contour to form a lip of the backing layer, the method comprising lifting the fibrous layer and the backing layer from the support surface to form the cut product, conveying the product to a removal means, contacting the lip of the backing layer with the removal means and separating the fibrous layer from the backing layer. 8. The method of claim 7 comprising contacting the fibrous layer with another fibrous layer, followed by pulling away the supporting layer while the other fibrous layer exerts an attractive force on the fibrous layer. 9. Method according to any of the preceding claims, wherein a force is exerted on the support layer by the support surface, which force is directed in the direction of the support surface. A method according to any preceding claim, wherein the fibrous layer and the support layer are reduced in temperature to separate the fibrous layer from the support layer. A method according to any preceding claim, wherein the target product is lifted by the actuator in a direction which forms an angle of less than 90 degrees with the surface of the support layer. A method according to any preceding claim, wherein the cut product is placed on a stack and/or in a mould. 13. A method according to claim 12, wherein the cut-out product is combined into a stack of similar cut-out products prior to placement in the mold. A method of making a cut-out product according to claim 1, comprising forming a first cut-out product according to any one of claims 3, 6 or 7 and a second cut-out product according to another of claims 3, 6 or 7. 15. A cut-out product comprising a fibrous layer impregnated with a matrix material lying on a backing layer, the backing layer and the fibrous layer having a common contour with an outwardly extending lip, the contour extending in a transverse direction from an initial position to an end position, the fibrous layer having a shallow cut portion extending from the initial position to the end position in a direction transversely oriented relative to the lip. 16. Apparatus for placing cut-out products formed from a sheet comprising a fibre layer impregnated with a matrix material and a lower support layer releasably supporting the impregnated fibre layer, the apparatus comprising: - a cutting station adapted to form a cut-out product according to any one of claims 1 to 13, - an end effector having a gripper adapted to pick up the cut product and remove the backing layer from the fibrous layer, and - a laminating surface for receiving cut products, the end effector being adapted to place the fibrous layer on the laminating surface. Apparatus according to claim 16, wherein the cutting station is adapted to form a cut-out product having a lip according to claim 7, the apparatus comprising a lip engaging unit adapted to grip the lip of the cut-out product while the fibrous layer is gripped by the gripper of the end effector, the lip engaging unit and the end effector being movable relative to each other for peeling the fibrous layer from the support layer.