DE112019006819T5 - Piece made from two fiber reinforced thermoplastic sections and method of making the same - Google Patents

Abstract

A piece (10) which has a first section (12) made of fiber-reinforced thermoplastic and a first connecting edge (12A) which is made by alternately arranging first projections (12B) and first recesses (12C), and a second section (14) which is made of fiber-reinforced thermoplastic and has a second connecting edge (14A) which is made by alternately arranging second projections (14B) and second recesses (14C), the first projections (12B) complementary to the second recesses (14C) and received in the second recesses (14C), wherein the second protrusions (14B) are complementary to the first recesses (12C) and are received in the first recesses (12C), and wherein the first protrusions (12B), the first recesses (12C), the second projections (14B) and the second recesses (14C) a form-fitting connection (22) between the first section (12) and d form the second section (14) against at least compressive and shear forces that occur in the connection surface of the form-fitting connection when the first section (12) and the second section (14) are flat, the form-fitting connection with a polymer (16 ) is poured over. A method of making the same.

Description

TECHNICAL AREA

The present invention relates to a piece made from fiber-reinforced thermoplastic and, more particularly, to a piece made from at least two fiber-reinforced thermoplastic sections or parts.

BACKGROUND

When making a piece of fiber reinforced thermoplastic, the piece can be cut from a flat sheet of fiber reinforced thermoplastic. The piece can then be formed into a 3D shape and then poured over with polymer.

Generally, more than one piece will be cut from a single sheet of fiber reinforced thermoplastic.

However, depending on the shape of the piece, a non-negligible portion of the plate may be wasted. For example, as in 1 shown, a plurality of pieces 202 cut from a sheet 200 of fiber reinforced thermoplastic material. It can be seen that a non-negligible portion of the plate 200 is not used and is disposed of as waste.

SUMMARY

It remains presently desirable to provide a piece made from fiber reinforced thermoplastic that makes better use of the fiber reinforced thermoplastic sheet.

Thus, according to embodiments of the present invention, a piece is provided. The piece includes a first portion made of fiber reinforced thermoplastic and includes a first connecting edge made by alternating first protrusions and first recesses, and a second portion made of fiber reinforced thermoplastic and including a second connecting edge made by alternating second projections and second recesses is made, wherein the first projections are complementary to the second recesses and are received in the second recesses and the second projections are complementary to the first recesses and are received in the first recesses, and wherein the first projections, first Recesses, second projections and second recesses form a positive connection between the first section and the second section against at least compressive and shear forces that occur in the connecting surface when the first section and the second section are flat are, wherein the positive connection is poured with a polymer.

By providing such a configuration, it is possible to make better use of the fiber-reinforced thermoplastic resin sheet and to reduce the portion of the sheet that is thrown away as waste material.

It is also possible to obtain a piece made from two fiber-reinforced thermoplastic sections that are assembled together by a form-fitting connection. Therefore, no glue is required to assemble the two sections together. Indeed, assembling two such sections with adhesive can be carried out by preparing the surfaces of the sections to be joined, applying an adhesive to the surfaces to be joined, fixing the sections together, and curing the adhesive. These steps are time consuming and costly.

In addition, thanks to the positive connection that is obtained by the complementary shapes of the respective first projections and the second recesses or the second projections and the first recesses, a good positioning of the two sections to each other with a mechanical positive connection of the first section and the second section can be achieved without additional weight.

If the first section and the second section are flat, i.e. not having a 3D shape, they essentially define a plane which represents the interlocking connection surface. Compressive forces are understood to be forces that press the first section in the direction of the second section in a direction essentially perpendicular to the general form-fitting connection direction, while shear forces are forces that are exerted in the plane in a direction essentially parallel to the general form-fit connection direction.

Since the first connecting edge is made from alternating first projections and first recesses, two successive first projections delimit a first recess. Likewise, two successive first recesses delimit a first projection. Since the second connecting edge is or is produced by alternating second projections and second recesses, two successive second projections delimit a second recess. Likewise, two successive second recesses delimit a second projection.

The polymer can be a thermoplastic or a thermosetting polymer. The polymer can be reinforced with fibers. For shape, the fibers are generally short. Non-limiting examples of the polymer are short glass fiber reinforced polypropylene, polyamide, acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphthalamide (PPA), polyetheretherketone (PEEK), epoxy (EP ), Polyurethane (PU).

The polymer can also be poured over sections of the first and second sections that differ from the form-fitting connection, i.e. That is, the polymer is poured over both on the form-fitting connection and on sections of the first and second section that differ from the form-fit connection.

In some embodiments, the first section and the second section can be cut from the same sheet of fiber reinforced thermoplastic.

The fiber-reinforced thermoplastic material can be a continuous fiber-reinforced thermoplastic material or a discontinuous fiber-reinforced thermoplastic material. The fibers can be non-woven mats or non-woven mats, woven fabrics, non-crimped woven fabrics or unidirectional layers with any direction. Non-limiting examples of fibers include glass fibers, carbon fibers, aramid fibers, and natural fibers. Non-limiting examples of thermoplastics include polypropylene, polyamide, acrylonitrile-butadiene-styrene (ABS), polycarbonate (PC), polybutylene terephthalate (PBT), polyethylene terephthalate (PET), polyphthalamide (PPA), polyetheretherketone (PEEK), epoxy (EP), and polyurethane (PU).

The plate made of fiber-reinforced thermoplastic material can have a thickness which is equal to or greater than 1 mm (millimeter), preferably equal to or greater than 1.5 mm and equal to or less than 5 mm and preferably equal to or less than 4.5 mm is.

In some embodiments, the first section and the second section can be cut from different sheets of fiber reinforced thermoplastic.

The first plate and the second plate made of fiber-reinforced thermoplastic material can be made of different fiber-reinforced thermoplastic material.

Thus, the first section and the second section are made from different fiber-reinforced thermoplastics.

The first plate and the second plate made of fiber-reinforced thermoplastic can be different plates made of the same fiber-reinforced thermoplastic.

Although made from the same fiber reinforced thermoplastic, the first section and the second section can be cut from different sheets.

The piece can include more than two sections that are assembled together using a positive connection. The piece may include three sections made of fiber reinforced thermoplastic and including a first connecting edge made by alternating first protrusions and first recesses, i.e., a first section, a second section and a third section. The piece can contain more than three sections.

According to some embodiments, the interlocking connection between the first section and the second section is against tensile forces that occur in the interlocking connection surface when the first section and the second section are flat.

Tensile forces are understood to mean forces which pull the first section and the second section apart in a direction essentially perpendicular to the general form-fitting connection direction.

According to some embodiments, the clips are arranged along the form-fitting connection, each clip having a first leg in the first section and a second leg in the second section.

The brackets can be metal brackets or plastic brackets. A bracket has two legs that are connected by a crown or a wreath. Each bracket has a first leg penetrating the first portion and folded over the first portion and a second leg penetrating the second portion and folded over the second portion so that the crown the interlocking connection crosses.

According to some embodiments, a fiberboard is at least partially covered with the thermoplastic material of both the first portion and the also impregnated the second section, the plate covering the form-fitting connection.

The outer surface of the fiberboard is flush with the surface of the first section and the second section. The fiberboard does not add any additional thickness to the first and second sections.

The fiber board can be a fleece mat, a woven fabric or a non-crimped fabric or a crease-free fabric. The fiberboard can include a binder.

The fibers of the fiberboard can be the same as the fibers of the first section and / or the second section.

The fiberboard can have a thickness that is equal to or greater than 0.10 mm (millimeters), preferably equal to or greater than 0.15 mm and equal to or less than 0.50 mm, preferably equal to or less than 0.45 mm.

According to some embodiments, the plate is a first plate and a second fiber plate is at least partially impregnated with the thermoplastic material of both the first section and the second section, the second plate covering the interlocking connection so that both sides of the interlocking connection are covered .

In some embodiments, the fiberboard is a sheet of fiber-reinforced thermoplastic material.

The thermoplastic plastic can be the same as the thermoplastic plastic of the first section and / or of the second section.

According to some embodiments, the first section is sewn to the second section at the form-fitting connection.

According to some embodiments, the first protrusions and the second protrusions have the same shape and dimensions.

Since the first cutouts are complementary to the second projections and the second cutouts are complementary to the first projections, it goes without saying that the first cutouts and the second cutouts have the same shape and the same dimensions.

According to some embodiments, the first protrusions, the first recesses, the second protrusions, and the second recesses have a dovetail shape.

With such a configuration of the projections and the recesses, the positive connection between the first section and the second section is secured against compressive, shear and tensile forces that occur in the connection surface when the first section and the second section are flat.

According to some embodiments, the first protrusions, the first recesses, the second protrusions, and the second recesses have a “T” shape.

With such a configuration of the projections and the recesses, the positive connection between the first section and the second section is secured against compressive, shear and tensile forces that occur in the connection surface when the first section and the second section are flat.

According to some embodiments, the first protrusions, the first recesses, the second protrusions and the second recesses have a crenellated or notched shape.

With such a configuration of the projections and the recesses, the positive connection between the first section and the second section is secured against compressive and shear forces that occur in the connection surface when the first section and the second section are flat.

According to some embodiments, the first protrusions and the second protrusions have different shapes and dimensions.

All of the first protrusions may have the same shape and dimensions, and all of the second protrusions may have the same shape and dimensions, while the shape and dimensions of the first protrusions may be different from the shape and dimensions of the second protrusions. Thus, all of the first recesses have the same shape and the same dimensions, and all the second recesses have the same shape and the same dimensions, the first recesses being complementary to the second projections and the second recesses being complementary to the first projections .

The first projections can have the shape of a mushroom, while the second projections have the complementary shape of the first recesses, which are delimited by the first projections.

With such a configuration of the projections and the recesses, the form-fit Connection between the first section and the second section secured against compressive, shear and tensile forces that occur in the connecting surface when the first section and the second section are flat.

The first protrusions can have different shapes and dimensions, with at least one first protrusion having a different shape and dimensions relative to the other first protrusions, and the second protrusions having different shapes and dimensions, with at least one second protrusion having a different shape and different Has dimensions relative to the other second projections.

With such a configuration of the projections and the recesses, the form-fitting connection between the first section and the second section is secured against compressive and shear forces which occur in the connection surface when the first section and the second section are flat.

• - Schneiden des ersten Abschnitts in eine erste Platte aus faserverstärktem Thermoplast, wobei der erste Abschnitt eine erste Verbindungskante aufweist, die aus abwechselnden ersten Vorsprüngen und ersten Aussparungen gefertigt ist, und Schneiden des zweiten Abschnitts in der ersten Platte oder in einer zweiten Platte aus faserverstärktem Thermoplast, wobei der zweite Abschnitt eine zweite Verbindungskante aufweist, die aus abwechselnden zweiten Vorsprüngen und zweiten Aussparungen gefertigt ist, wobei die ersten Vorsprünge komplementär zu den zweiten Aussparungen sind und die zweiten Vorsprünge komplementär zu den ersten Aussparungen sind;
• - Montieren des ersten Abschnitts an den zweiten Abschnitt durch formschlüssiges Verbinden der ersten Verbindungskante und der zweiten Verbindungskante durch Aufnehmen der ersten Vorsprünge in den zweiten Aussparungen und der zweiten Vorsprünge in den ersten Aussparungen, um eine formschlüssige Verbindung zwischen dem ersten Abschnitt und dem zweiten Abschnitt gegen mindestens Druck- und Scherkräfte zu bilden, die in der formschlüssigen Verbindungsfläche auftreten, wenn der erste Abschnitt und der zweite Abschnitt flach sind, und wenn ein Zusammenbau des ersten und des zweiten Abschnitts erfolgt;
• - Erwärmen des Zusammenbaus, um einen erweichten Zusammenbau zu erhalten;
• - Formen des erweichten Zusammenbaus in einer formgebenden Form, um einen gebildeten Zusammenbau zu erhalten;
• - Übergießen mindestens der formschlüssigen Verbindung des gebildeten Zusammenbaus mit einem Polymer, um das Stück zu erhalten.

According to embodiments of the present invention, a method of manufacturing a piece by assembling a first portion of fiber reinforced thermoplastic and a second portion of fiber reinforced thermoplastic is provided. The procedure includes:

• - Cutting the first section in a first plate made of fiber-reinforced thermoplastic, wherein the first section has a first connecting edge which is made of alternating first projections and first recesses, and cutting the second section in the first plate or in a second plate made of fiber-reinforced thermoplastic wherein the second portion has a second connecting edge made of alternating second protrusions and second recesses, the first protrusions being complementary to the second recesses and the second protrusions being complementary to the first recesses;
• - Assembling the first section to the second section by positively connecting the first connecting edge and the second connecting edge by receiving the first projections in the second recesses and the second projections in the first recesses in order to provide a form-locking connection between the first section and the second section to form at least compressive and shear forces which occur in the interlocking connection surface when the first section and the second section are flat and when the first and second sections are assembled;
• Heating the assembly to obtain a softened assembly;
• Molding the softened assembly in a forming mold to obtain a formed assembly;
• - Overmolding of at least the interlocking connection of the assembly formed with a polymer in order to obtain the piece.

It goes without saying that the overmolding can include a cooling step.

The heating step can be carried out in an infrared oven.

The heating temperature is between the glass transition temperature and the melting temperature of the thermoplastic material.

According to some embodiments, the interlocking connection between the first section and the second section is against tensile forces that occur in the interlocking connection surface when the first section and the second section are flat.

According to some embodiments, the method includes a step of strengthening the form-fitting connection.

Reinforcing the interlocking connection can help stabilize the interlocking connection during handling during assembly and can prevent misalignment of the two sections in the forming mold, since the sections are softer and more malleable than at room temperature.

According to some embodiments, the step of reinforcing the form-fitting connection is carried out between the step of assembling and the step of heating.

According to some embodiments, the step of reinforcing the interlocking connection includes tacking the interlocking connection with hot clips, each clip having a first leg in the first section and a second leg in the second section.

The use of hot staples enables the reinforcing step to be performed without heating the first and second sections. The hot clips namely soften the thermoplastic material during the penetration of the legs of the clips into the thermoplastic material. The brackets can be made of metallic alloys, such as. B. steel, manufactured be. The brackets can be made of polymer, such as. B. polyamide, be made.

According to some embodiments, the step of reinforcing the interlocking connection includes hot pressing a plate made of fibers onto the interlocking connection.

The fiberboard can improve the guidance of the injected thermoplastic resin during the overmolding step.

According to some embodiments, the step of reinforcing the interlocking connection includes hot pressing a sheet of fibers on each side of the interlocking connection.

According to some embodiments, the step of reinforcing the form-fitting connection is carried out during the step of heating.

According to some embodiments, the step of reinforcing the interlocking connection includes the stapling of the interlocking connection with clips, each clip having a first leg in the first section and a second leg in the second section.

During the heating step, the thermoplastic plastic of the first section and the second section is softened, and the legs of the clamps can penetrate the thermoplastic plastic. The brackets can be made of metallic alloys, such as. B. steel, or made of polymers such. B. polyamide, be made.

According to some embodiments, the step of reinforcing the interlocking connection includes sewing the first section to the second section on the interlocking connection.

The material for sewing can be a thread, e.g. B. a polyester yarn, a polyamide yarn, etc.

It is intended that combinations of the elements mentioned above and those mentioned in the specification can be made, unless there are contradictions.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not limiting of the invention as claimed.

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles thereof.

Figure list

• 1 shows an illustration of a plate made of fiber-reinforced thermoplastic material with a known section;
• 2 Figure 12 is an illustration of an exemplary piece in accordance with embodiments of the present invention;
• 3 Figure 12 is an illustration of an exemplary fiber reinforced thermoplastic resin sheet showing cutting in accordance with embodiments of the present invention;
• 4th FIG. 11 is an illustration of an exemplary first section and a second section in accordance with embodiments of the present invention; FIG.
• 5 FIG. 11 is an illustration of an exemplary assembly in accordance with embodiments of the present invention; FIG.
• 6th FIG. 11 shows an illustration of an exemplary assembly according to embodiments of the present invention; FIG.
• 7th shows a schematic representation of an enlargement of 4th ;
• 8th shows the sections of 7th during assembly;
• 9 shows the sections of 7th after assembly;
• 10 shows the sections of 7th after pouring over;
• 11th until 14th show enlargements of other exemplary assemblies in accordance with embodiments of the present invention;
• 15th Figure 12 shows the step of overmolding in accordance with embodiments of the present invention;
• 16A until 16C show the covering of the form-fitting connection with two fiber boards according to embodiments of the present invention;
• 17th shows a representation of an exemplary assembly with reinforced positive connection according to embodiments of the present invention;
• 18th and 19th show further exemplary assemblies with reinforced form-fitting connection according to embodiments of the present invention; and
• 20th shows a flow diagram of the method according to embodiments of the present invention.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used in the drawings to refer to the same or like parts.

2 Figure 12 shows a representation of an exemplary piece 10 in accordance with embodiments of the present invention. The piece 10 includes a first section 12th and a second section 14th , each made of fiber-reinforced thermoplastic, the first section 12th and the second section 14th with a polymer 16 are poured over.

20th shows a flow diagram of a method 100 to make the piece 10 in accordance with embodiments of the present invention.

As in 3 As shown, the method includes one step 102 cutting the first section 12th and the second section 14th in a plate 18th made of fiber-reinforced thermoplastic material.

As from comparing the 1 and 3 it can be seen it is possible to cut the section of the plate 18th made of fiber-reinforced thermoplastic, which is thrown away as waste material, since it is possible to reduce in 3 a bit more from the record 18th than to cut it in 1 was possible.

For example, the first section 12th and the second section 14th from the same plate 18th be cut from fiber-reinforced thermoplastic material. The first paragraph 12th and the second section 14th can also be made from two different panels 18th get cut.

The sheet of fiber reinforced thermoplastic material can be a continuous glass fiber reinforced polypropylene that has a thickness 20A of 2 mm (see 15th ). For example, glass fiber reinforced polypropylene, such as Lanxess Tepex® Dynalite 104-RG600 (2) -RGUDm317 (4) / 48% black type S. ) can be used with a (0/90 / - 45 / + 45) s lamination or with a (0/90 / - 45 / + 45) s layup.

As in 3 shown includes the first section 12th a first connecting edge 12A , and the second section 14th includes a second connecting edge 14A .

As in the 4th and 5 shown will be the first section 12th and the second section 14th along the first and second connecting edges 12A , 14A assembled together. Assembling the first and second connecting edges 12A , 14A forms a form-fitting connection 22nd between the first section 12th and the second section 14th . Once the step of assembling 104 is carried out, an assembly is obtained 20th of the first section 12th and the second section 14th .

The assembly 20th is flat and has the thickness of the plate 18th on to which the first section 12th and the second section 14th were cut.

As in 5 shown, the positive connection is effective 22nd while holding the first section together 12th and the second section 14th against at least compressive forces C. and shear forces S. that can occur in the connection surface of the form-fitting connection when the first section 12th and the second section 14th are flat, i.e. as in 5 shown.

In step 106 is assembling 20th heated to obtain a softened assembly, that is, an assembly in which the thermoplastic resin is softened and can be deformed without breaking. The step of warming 106 can be carried out in an infrared oven between the glass transition temperature and the melting temperature of the thermoplastic material.

In step 108 the softened assembly is then transformed into a shaping shape 120 (please refer 15th ) to give the softened assembly the desired shape, thereby creating a molded assembly 24 is obtained as in 6th shown. The molded assembly 24 is shaped by the softened assembly against a lower section 120B the shaping form 120 is pressed. Form 120 then closes and an upper section 120A the shaping form 120 can touch the softened assembly and shape it.

Once the molded assembly 24 is obtained can overmolding the molded assembly 24 during the overmolding step 110 take place. During the step 110 , as in 6th Shown is the molded assembly 24 on the lower section 120B the shaping form 120 on, and the polymer 16 gets into the cavities 120C the shaping form 120 injected between the molded assembly 24 and the top section 120A the shaping form 120 exist so that the polymer 16 finally the molded assembly 24 against the lower section 120B expresses what gives the final shape.

Once the cavity 120C with the polymer 16 is filled, the injection of the polymer is stopped and the polymer is treated so that it becomes hard. So you get at the end of step 110 the piece 10 .

When the polymer 16 is a thermoplastic polymer, the polymer is cured by lowering the temperature of the polymer. When the polymer 16 is a thermosetting polymer, the polymer is cured.

As in the 7th until 10 shown can the procedure 100 on first and second sections 12th , 14th the first and second connecting edges are applied 12A , 14A which are made of alternating projections and recesses that have the same shape and dimensions.

As in 7th shown, one cuts when cutting the first section 12th the first connection edge 12A that consist of alternating first protrusions 12B and first cutouts 12C is made. In the non-limiting example of 7th have the first protrusions 12B and the first notches 12C a dovetail shape. Likewise, cut when cutting the second section 14th the second connection edge 14A that consist of alternating second protrusions 14B and second recesses 14C is made. In the non-limiting example of 7th have the second protrusions 14B and the second recesses 14C a dovetail shape. The first protrusions 12B have a complementary shape to the shape of the second recesses 14C on, and the second protrusions 14B have a complementary shape to the shape of the first recesses 12C on.

As in 9 shown is the assembly of the first section 12th on the second section 14th by form-fitting connection of the first connection edge 12A and the second connecting edge 14A by picking up the first protrusions 12B in the second recesses 14C and the second protrusions 14B in the first notches 14B manufactured to the form-fitting connection 22nd between the first section 12th and the second section 14th to build. Thus, the first form protrusions 12B , the first notches 12C , the second protrusions 14B and the second recesses 14C the positive connection 22nd between the first section 12th and the second section 14th .

With such a configuration of the first and second protrusions 12B , 14B and the first and second recesses 12C , 14C is the form-fitting connection 22nd between the first section 12th and the second section 14th against pressure forces C. , Shear forces S. and tensile forces T that occur in the interlocking connection surface when the first section 12th and the second section 14th are flat, secured.

As in 10 shown is the polymer 16 after the pouring step 110 at least over the form-fitting connection 22nd Poured over, ie the polymer is over the form-fitting connection 22nd poured over, and other sections of the formed assembly 24 can also with the overmolded polymer 16 be covered.

the 11-14 are similar to that 9 . 11-14 are illustrations of other exemplary assemblies according to embodiments of the present invention.

The assembly 20th the 11th differs from the assembly 20th the 9 in that the first protrusions 12B , the first notches 12C , the second protrusions 12C and the second recesses 12C have a "T" shape. The first and second sections 12th , 14th showing the first and second connecting edges 12A , 14A are made of alternating projections and recesses that have the same shape and dimensions.

With such a configuration of the first and second protrusions 12B , 14B and the first and second recesses 12C , 14C is the form-fitting connection 22nd between the first section 12th and the second section 14th against pressure forces C. , Shear forces S. and tensile forces T that occur in the interlocking connection surface when the first section 12th and the second section 14th are flat, secured.

The assembly 20th the 12th differs from the assembly 20th the 9 in that the first protrusions 12B have a mushroom shape, ie, each first protrusion 12B has a shaft 12BA and a head 12BB on. The second protrusions 14B have a complementary shape to the shape of the first recesses 12C on that of two consecutive protrusions 12B be limited. Thus, all of the first have projections 12B the same shape and dimensions on all other protrusions 14B have the same shape and dimensions, and the first protrusions 12B and the second protrusions 14B have different shapes and dimensions.

With such a configuration of the first and second protrusions 12B , 14B and the first and second recesses 12C , 14C is the form-fitting connection 22nd between the first section 12th and the second section 12th against pressure forces C. , Shear forces S. and tensile forces T that occur in the interlocking connection surface when the first section 12th and the second section 14th are flat, secured.

The assembly 20th the 13th differs from the assembly 20th the 9 in that the first connecting edge 12A and the second connecting edge 12B have a crenellated or notched shape, ie, the first protrusions 12B , the first notches 12C , the second protrusions 12C and the second recesses 12C have a crenellated or notched shape. The first protrusions 12B , the first notches 12C , the second protrusions 14B and the second recesses 14C have the same shape and dimensions.

With such a configuration of the first and second protrusions 12B , 14B and the first and second recesses 12C , 14C is the form-fitting connection 22nd between the first section 12th and the second section 14th against pressure forces C. and shear forces S. that occur in the interlocking connection surface when the first section 12th and the second section 14th are flat, secured.

The assembly 20th the 14th differs from the assembly 20th the 9 in that the first protrusions 12BA have a different shape and dimensions than the first protrusions 12BB . The second protrusions 14B have a complementary shape to the shape of the first recesses 12C on that of two consecutive protrusions 12B be limited. The first projections thus have 12B a different shape and dimensions, and the second protrusions 14B have a different shape and dimensions, and the first protrusions 12B and the second protrusions 14B have a different shape and dimensions.

With such a configuration of the first and second protrusions 12B , 14B and the first and second recesses 12C , 14C is the form-fitting connection 22nd between the first section 12th and the second section 12th against pressure D and shear forces S. that occur in the interlocking connection surface when the first section 12th and the second section 14th are flat, secured.

In the 17th until 19th are exemplary, reinforced form-fitting connections 22nd shown.

As in 17th shown is the form-fitting connection 22nd with a fiber board 26th covered with the thermoplastic material of both the first section 12th as well as the second section 14th is impregnated. For the plate 26th an endless glass fiber reinforced polypropylene UD tape material (Sabic UDmax GPP 45-70 ) be used.

In the non-limiting example of 17th is the outer surface of the fiberboard 26th flush with the surface of the first section 12th and the second section 14th . The fiberboard 26th does not add to the thickness of the first and second sections 12th , 14th at. Glass, carbon, aramid or natural fibers can be used. Nonwovens (e.g. glass fiber nonwovens with a surface weight of 34 g / m ² and a thickness of non-woven only 0.29 mm) or glass fiber UD tapes with a thickness of 0.25 mm, a fiber content of 45 vol. % and a polypropylene matrix can be used.

As in 17th shown is the fiberboard 26th on one side of the positive connection 22nd appropriate.

Another non-limiting example is fiberboard 26th both sides of the positive connection 22nd cover.

As in the 16A until 16C and 20th shown can the step 112 of strengthening the positive connection 22nd between the step of assembling 104 and the step of heating 106 occur.

The fiberboard (s) 26th can / can before heating on the assembly 20th be hot-pressed.

As in 16A shown is the thickness 26A the fiberboard 26th small compared to the thickness 20A of assembly 20th . As a non-limiting example, the thickness 26A be equal to 0.2 mm.

The assembly 20th and the fiberboard (s) 26th are in the cavity of a hot press 140 between a top plate 140A and a lower plate 140B arranged, the fiberboard (s) 26th on the top plate 140A and / or the lower plate 140B are arranged so that they form the positive connection 22nd cover when the reinforcing step 112 is or will be ended. The fiberboard (s) 26th can with the help of vacuum holders on the top plate 140A and / or the lower plate 140B be attached. The top and bottom plate 140A , 140B are heated and brought closer together in order to make the fiberboard (s) 26th in the assembly 20th to press. The thermoplastic of the assembly melts under the action of the heat 20th partially and penetrates the fibreboard (s) 26th a, the thermoplastic between the fibers of the fiberboard (s) 26th is available. The plate (s) is / are thus at least partially with the thermoplastic material of the assembly 20th impregnated.

The top plate 140A and the lower plate 140B can be brought closer together, and the fibreboard (s) 26th will continue towards and into the assembly 20th pushed so that they form a surface that is flush with the surface of the assembly 20th is flush.

As in 18th shown, the form-fitting connection 22nd with brackets 28 be reinforced along the form-fitting connection 22nd are arranged, each bracket 28 a first leg 28A and a second leg 28B includes, by a crown or a wreath 28C are connected to each other. Every bracket 28 has the first leg 28A who made the first section 12th penetrates and over the first section 12th is folded, and the second leg 28B who made the second section 14th penetrates and over the second section 14th is folded up, so that the crown 28C the positive connection 22nd crosses or crosses.

As in 20th Shown can be the reinforcing step 112 either between the step of assembling 104 and the step of heating 106 or during the heating step 106 be performed.

When performing between the step of assembling 104 and the step of heating 106 it is preferred that the brackets 28 be heated. The use of hot brackets 28 allows the reinforcing step 112 without warming up the first and second sections 12th , 14th perform. In fact, the hot brackets are softening 28 the thermoplastic material during the penetration of the legs 28A , 28B of the brackets 28 in the thermoplastic plastic. The clips can be made of metallic alloys, such as steel, or of polymers, such as polyamide.

When performed during the heating step 106 , need the brackets 28 not be heated. During the heating step 106 becomes the thermoplastic of the first section 12th and the second section 14th softened, and the thighs 28A , 28B of the brackets 28 can penetrate the thermoplastic material. The clips can be made of metallic alloys or of polymer.

As in 19th shown, the form-fitting connection 22nd by sewing the first section 12th with the second section 14th on the form-fitting connection 22nd be reinforced.

During the heating step 106 becomes the thermoplastic of the first section 12th and the second section 14th softened, and the first section 12th can with the second section 14th on the form-fitting connection 22nd be sewn.

Throughout the entire description, including the claims, the term “comprising a” is to be understood as synonymous with “at least one”, unless stated otherwise. In addition, each range indicated in the description, including the claims, should be understood to include its final value or values, unless otherwise stated. Specific values for elements described should be understood to be within acceptable manufacturing or industrial tolerances known to one skilled in the art, and any use of the terms “substantially” and / or “approximately” and / or “generally” should be so understood to be within such accepted tolerances.

While the present invention has been described with reference to particular embodiments, it is to be understood that these embodiments are merely illustrative of the principles and applications of the present invention.

It is intended that the specification and examples be considered as exemplary only, with a true scope of the invention being indicated by the following claims.

Claims (20)

Piece (10) which has a first section (12) made of fiber-reinforced thermoplastic and a first connecting edge (12A) which is made by alternately arranging first projections (12B) and first recesses (12C), and a second Has section (14) which is made of fiber-reinforced thermoplastic and has a second connecting edge (14A) which is made by alternately arranging second projections (14B) and second recesses (14C), the first projections (12B) being complementary to the are second recesses (14C) and are received in the second recesses (14C), wherein the second projections (14B) are complementary to the first recesses (12C) and are received in the first recesses (12C), and wherein the first projections (12B), the first recesses (12C), the second projections (14B) and the second recesses (14C) form a positive connection (22) between the first section (12) and the second section (14) Form at least compressive and shear forces that occur in the connection surface of the form-fitting connection when the first section (12) and the second section (14) are flat, the form-fitting connection being overmolded with a polymer (16). Piece (10) after Claim 1 , wherein the form-fitting connection (22) between the first section (12) and the second section (14) is against tensile forces that occur in the form-fitting connection surface when the first section (12) and the second section (14) are flat. Piece (10) after Claim 1 or 2 wherein clips are arranged along the form-fitting connection (22), each clip having a first leg (28A) in the first section (12) and a second leg (28B) in the second section (14). Piece (10) after one of the Claims 1 until 3 wherein a fiberboard (26) is at least partially impregnated with the thermoplastic material of both the first section (12) and the second section (14), and wherein the fiberboard (26) covers the interlocking connection (22). Piece (10) after Claim 4 , wherein the fiberboard (26) is a first fiberboard (26), and a second fiberboard is at least partially impregnated with the thermoplastic material of both the first section (12) and the second section (14), and wherein the second plate is the form-fitting Connection (22) covers so that both sides of the positive connection (22) are covered. Piece (10) after Claim 4 or 5 wherein the fiber board (26) is a board made of fiber-reinforced thermoplastic material. Piece (10) after Claim 1 or 2 , wherein the first section (12) is sewn to the second section (14) on the form-fitting connection (22). Piece (10) after one of the Claims 1 until 7th wherein the first protrusions (12B) and the second protrusions (14B) have the same shape and dimensions. Piece (10) after Claim 8 wherein the first protrusions (12B), the first recesses (12C), the second protrusions (14B) and the second recesses (14C) have a dovetail shape. Piece (10) after one of the Claims 1 until 7th wherein the first protrusions (12B) and the second protrusions (14B) have different shapes and dimensions. Method (100) for manufacturing a piece (10) by assembling a first section (12) made of fiber-reinforced thermoplastic and a second section (14) made of fiber-reinforced thermoplastic, comprising: - Cutting (102) the first section (12) into a first plate (18) made of fiber-reinforced thermoplastic, the first section (12) having a first connecting edge (12A), which is created by alternately arranging first projections (12B) and first recesses (12C) is made, and cutting the second section (14) in the first plate (18) or in a second plate made of fiber-reinforced thermoplastic, the second section (14) having a second connecting edge (14A), which is formed by alternately arranging second projections (14B) and second recesses (14C) is made, wherein the first projections (12B) are complementary to the second recesses (14C) and the second projections (14B) are complementary to the first recesses (12C); - Mounting (104) the first section (12) on the second section (14) by positively connecting the first connecting edge (12A) and the second connecting edge (14A) by receiving the first projections (12B) in the second recesses (14C) and the second projections (14B) in the first recesses (14B) to form a form-fitting connection (22) between the first section (12) and the second section (14) against at least compressive and shear forces that occur in the form-fitting connection surface when the first section (12) and the second section (14) are flat and when there is an assembly (20) of the first and second sections (12, 14); - heating (106) the assembly (20) to obtain a softened assembly; - molding (108) the softened assembly in a forming mold (120) to obtain a molded assembly (24); - Overmolding (110) at least the positive connection (22) of the molded assembly (24) with a polymer in order to obtain the piece (10). Method (100) according to Claim 11 , wherein the form-fitting connection between the first section (12) and the second section (14) is against tensile forces that occur in the form-fitting connection surface when the first section (12) and the second section (14) are flat. Method (100) according to Claim 11 or 12th , comprising a step of reinforcing (112) the form-fitting connection (22). Method (100) according to Claim 13 , wherein in the step of reinforcing (112) the form-fitting connection (22) is carried out between the step of assembling (104) and the step of heating (106). Method (100) according to Claim 14 wherein the step of reinforcing (112) the interlocking connection (22) comprises tacking the interlocking connection (22) with hot clips, each clip having a first leg in the first section and a second leg in the second section. Method (100) according to Claim 14 or 15th wherein the step of reinforcing (112) the interlocking connection (22) comprises hot pressing a fiber board (26) onto the interlocking connection (22). Method (100) according to Claim 14 or 15th wherein the step of reinforcing (112) the interlocking connection (22) comprises hot pressing a fiber board (26) onto each side of the interlocking connection (22). Method (100) according to Claim 13 wherein the step of reinforcing (112) the form-fitting connection (22) is carried out during the step of heating (106). Method (100) according to Claim 18 , wherein the step of reinforcing (112) the form-fitting connection (22) comprises tacking the form-fitting connection (22) with clips (28), each clip (28) having a first leg (28A) in the first section (12) and has a second leg (28B) in the second section (14). Method (100) according to Claim 18 or 19th wherein the step of reinforcing (112) the interlocking connection (22) comprises sewing the first section (12) to the second section (14) on the interlocking connection (22).

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