Composite material light connecting band plate structure and forming method thereof

Abstract

The invention discloses a composite material light connecting band plate structure and a forming method thereof, and relates to the technical field of composite material structure manufacturing. A thermoplastic composite material laminated flat plate is adopted for preparing a linear, L-shaped or Z-shaped preformed body, a through hole is machined in the connecting end, a connecting part matched with a bolt is formed at the outer side end of the through hole while the preformed body is subjected to hot-pressing curing, an internal thread embedded part is adopted, an internal thread connecting ring is attached to the through hole, and an injection molding shell is formed through thermoplastic resin melt. A nut piece is adopted, two injection molding frames are formed on the two sides of a penetrating hole through thermoplastic resin melt to form a nut clamping groove, rectangular positioning wings are arranged on the periphery of the nut piece and clamped in the nut clamping groove, and the nut piece and the preformed body are pressed and positioned through an elastic positioning piece. The preformed body is prepared based on the thermoplastic composite material laminated plate, the connecting part is formed by assembling the internal thread insert or the nut after the connecting end is perforated, the preparation is simple and efficient, and the manufacturing cycle cost is low.

Description

Technical Field

[0001] The invention relates to the technical field of composite material structure manufacturing, in particular to a composite material lightweight connecting strip plate structure and a molding method thereof. Background Art

[0002] The connecting strip plate structure mainly serves as a "bridge" for connecting multiple parts. Its structural efficiency advantage is obvious, especially in the aerospace field. For example, in large aircraft wing panels, leading and trailing edge panels and other structural aerodynamic surfaces have high requirements and need to compensate for the docking step difference of the structure to be connected. The connecting strip plate structure has high structural efficiency here and has been widely used.

[0003] However, the structural efficiency design and manufacturing technology of connecting strip plate structures are relatively complex. Currently, most connecting strip plate structures are metal structures and are processed by metal machinery. There are problems such as complex surface, difficult processing, and heavy structure weight.

[0004] In order to reduce weight, lightweight and high-strength composite material connecting strip plate structures are gradually being used. However, the current connecting strip plate structures generally adopt conventional thermosetting resin matrix composite material prepregs for paving, then undergo autoclave curing and molding, and then combine with machining to obtain them. There are problems such as difficult paving, long curing cycle, long production hours, high manufacturing cost, and low efficiency. Therefore, it is urgent to optimize and improve the connecting strip plate structure and its molding method, so that the preparation of the connecting strip plate structure is simpler and more efficient, so as to solve the problem of manufacturing cycle cost. Summary of the invention

[0005] In order to solve the shortcomings of the background technology, the present invention provides a composite lightweight connecting strip plate structure and a forming method thereof. It is based on a thermoplastic composite laminated flat plate to prepare a type I, L-shaped or Z-shaped preform. After the connecting end is processed and perforated, it is assembled through an internal threaded insert or a nut to form a connecting component that cooperates with the bolt. The preparation is simple and efficient, and the manufacturing cycle cost is low.

[0006] To achieve the above object, the present invention adopts the following technical solutions:

[0007] A composite material lightweight connecting strip plate structure, using a type of connecting strip plate, an L-shaped connecting strip plate or a Z-shaped connecting strip plate, the connecting strip plate structure body uses a thermoplastic composite laminated flat plate as a type of preform or is prepared by a corresponding hot pressing molding tool to obtain an L-shaped or Z-shaped preform, the connecting ends on both sides of the preform are respectively processed and provided with a plurality of perforations along the width direction, and while the preform is hot pressed and cured, a connecting component that cooperates with a bolt is formed at the outer end of each perforation to form a connecting strip plate structure as a whole, the connecting component is an internal threaded embedded part or a nut part, and when the internal threaded embedded part is used, the internal threaded embedded part The internal threaded connecting ring is coaxially attached to the perforation and an injection-molded shell is formed on its outside by thermoplastic resin melt during hot pressing and curing to form an integrated body with the preform. When the nut member is used, two injection-molded frames are integrally formed on both sides of the perforation by thermoplastic resin melt during hot pressing and curing, a nut slot is formed between the two injection-molded frames, and two V-shaped grooves are relatively hollowed out at the middle positions of the inner sides of the two injection-molded frames. The nut member is coaxially attached to the perforation, and a rectangular positioning wing is integrally provided around the nut member and is clamped in the nut slot, and is clamped between the two V-shaped grooves by an elastic positioning member to press and position the nut member and the preform.

[0008] Furthermore, the connecting ends on both sides of the preform are respectively cut by machining to remove excess between each two adjacent perforations to form a toothed structure.

[0009] Furthermore, the outer wall of the internal thread connecting ring adopts a stepped structure.

[0010] Furthermore, the elastic positioning member is a diamond-shaped structure with one end open and formed by bending a metal rod.

[0011] Furthermore, the thermoplastic composite laminate is reinforced with continuous fibers.

[0012] A method for forming a composite material lightweight connecting strip plate structure, comprising the following steps:

[0013] Step 1: Select a thermoplastic composite laminated plate according to the use requirements of a type I connecting strip, an L-shaped connecting strip or a Z-shaped connecting strip. For a type I connecting strip, directly cut the thermoplastic composite laminated plate to obtain a type I preform. For an L-shaped connecting strip or a Z-shaped connecting strip, press the thermoplastic composite laminated plate through a corresponding hot pressing tool to obtain an L-shaped or Z-shaped preform, and a margin is left at the edge of the preform.

[0014] Step 2: According to the design dimensions, the edge of the preform is machined to remove the excess, and then holes are processed at the connecting ends on both sides of the preform;

[0015] Step 3: Place the preform that has been pierced into an integrated injection mold for positioning. If an internal threaded insert is selected as a connecting component, an internal threaded connecting ring must also be installed and placed. The molding surface of the integrated injection mold is designed according to the configuration of the preform, and is provided with an injection channel and a cavity for molding an injection molded shell or two injection molded frames.

[0016] Step 4: feeding a thermoplastic resin melt into a corresponding position inside the injection molding integrated mold through an injection molding channel to prepare and mold the injection molding shell or two injection molding frames, and heating and pressurizing the injection molding integrated mold to achieve integrated preparation of the internal thread insert or the nut slot and the preform;

[0017] Step 5: After cooling, demolding is performed to cut off the residual injection material. If a nut is selected as a connecting component, two V-shaped grooves need to be hollowed out and the nut and the preform are pressed and positioned by elastic positioning parts to obtain a composite material lightweight connecting strip plate structure.

[0018] Furthermore, the integrated injection molding combination mold includes a female mold and a male mold whose molding surfaces match the preform configuration, and positioning pins are fixedly arranged at positions corresponding to the perforations on the inner bottom surface of the female mold for positioning the preform, an injection hole is arranged on the top of the male mold, and an injection channel is arranged inside the male mold and connected to the injection hole, and a cavity is arranged at the end of the injection channel. The cavity is divided into an embedding injection cavity corresponding to the injection molding shell or a nut slot injection cavity corresponding to the two injection molding frames according to the selection of connecting parts.

[0019] Furthermore, the injection channel of the integrated injection mold also extends to the connecting ends on both sides of the preform, so that plate end injection molding edges can be formed at both ends of the preform during the thermoplastic resin melt injection molding process.

[0020] Compared with the prior art, the beneficial effects of the present invention are as follows: the present invention prepares a type I, L-type or Z-type preform based on a thermoplastic composite laminated flat plate, selects the application according to the profile to be connected, and after the connection end is processed and perforated, it is assembled through an internal threaded insert or a nut part to form a connecting component that cooperates with the bolt. The internal threaded insert integrates the internal threaded connecting ring with the preform through a thermoplastic resin melt during hot pressing and curing. The nut part is pressed and positioned in a nut slot formed by the thermoplastic resin melt during hot pressing and curing of the preform through an elastic positioning part. The connecting component is easy to assemble and adopts thermoplastic compression molding. The preparation is simple and efficient, the manufacturing cycle cost is low, it can be flexibly used for components to be connected with different profiles, and it can be widely applied. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a schematic diagram of the assembly of a type of connecting strip plate of the present invention;

[0022] Figure 2 It is a schematic diagram of assembling the L-shaped connecting strip plate of the present invention;

[0023] Figure 3 The Z-type connecting strip of the present invention is shown in FIG. Figure 1 ;

[0024] Figure 4 The Z-type connecting strip of the present invention is shown in FIG. Figure 2 ;

[0025] Figure 5 is a schematic diagram of hot pressing of a preform of the present invention;

[0026] Figure 6 It is a schematic diagram of the toothed structure of the connecting strip plate of the present invention;

[0027] Figure 7 It is a structural schematic diagram of the internal thread embedding piece of the present invention;

[0028] Figure 8 It is a structural schematic diagram of the nut clamping slot of the present invention;

[0029] Fig. 9 It is a structural schematic diagram of the injection molding integrated combined mold of the present invention;

[0030] Fig.10 It is a schematic diagram of the disassembly of the connecting strip plate and the nut member of the present invention;

[0031] Fig.11 It is a schematic diagram of assembling the connecting strip plate and the nut member of the present invention.

[0032] In the figure: 01-bolt, 02-plate 1 to be connected, 03-plate 2 to be connected, 04-perforation, 05-shim, 06-tooth structure, 07-nut, 10-type connecting strip, 20-L-type connecting strip, 30-Z-type connecting strip, 50-internal thread embedding, 51-injection molding shell, 52-internal thread connecting ring, 60-nut slot, 61-injection molding frame, 62-elastic positioning piece, 70-thermoplastic composite laminated plate, 71-hot pressing molding tool, 72-preform, 80-female mold, 81-male mold, 82-embedded mold injection cavity, 83-locating pin, 84-molding surface, 85-injection molding hole, 86-injection molding channel, 87-plate end injection molding edge sealing. DETAILED DESCRIPTION

[0033] The technical solution of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0034] like Figures 1 to 11 As shown, a composite material lightweight connecting strip plate structure adopts a type I connecting strip plate 10, an L-shaped connecting strip plate 20 or a Z-shaped connecting strip plate 30.

[0035] Combination Figure 5 As shown, the connecting strip structure body uses a thermoplastic composite laminated flat plate 70 as a preform 72 of a type or prepares an L-shaped or Z-shaped preform 72 through a corresponding hot press forming tool 71. The thermoplastic composite laminated flat plate 70 is a preform, and continuous fibers are preferably used for reinforcement during the preparation process. The thickness of the layer can be determined according to the strength or other engineering design requirements. This figure only shows the configuration of the hot press forming tool 71 and the preform 72 corresponding to the Z-shaped connecting strip 30. The L-shaped connecting strip 20 can be prepared by simply adjusting the configuration of the pressing surface of the hot press forming tool 71.

[0036] Combination Figure 6 to Figure 8 , Figure 10-11 As shown, the connection ends on both sides of the preform 72 are respectively processed and provided with a plurality of through holes 04 along the width direction, and a connection component cooperating with a bolt 01 is formed at the outer end of each through hole 04 while the preform 72 is hot pressed and solidified, thereby forming a connection strip plate structure as a whole, and the connection component is an internal threaded insert 50 or a nut 07. In addition, in order to reduce the counterweight, the connection ends on both sides of the preform 72 can be respectively machined and cut to remove the excess between each two adjacent through holes 04 to form a toothed structure 06.

[0037] Combination Figure 7 As shown, when the internal thread insert 50 is used, the internal thread insert 50 is coaxially attached to the through hole 04 by the internal thread connecting ring 52 and is integrally formed with the preform 72 by forming an injection molded shell 51 on its exterior through a thermoplastic resin melt during hot pressing and curing. The outer wall of the internal thread connecting ring 52 preferably adopts a stepped structure, which helps to improve the stability of the internal thread connecting ring 52 and the preform 72 after the injection molded shell 51 is formed.

[0038] Combination Figure 10-11As shown, when the nut member 07 is used, two injection molding frames 61 are integrally formed on both sides of the perforation 04 by the thermoplastic resin melt during hot pressing and curing, a nut clamping groove 60 is formed between the two injection molding frames 61, and two V-shaped grooves are relatively hollowed out at the middle positions of the inner sides of the two injection molding frames 61, the nut member 07 is coaxially abutted against the perforation 04, and a rectangular positioning wing is integrally provided around the nut member 07 to cooperate with and clamp in the nut clamping groove 60, and is clamped between the two V-shaped grooves by an elastic positioning member 62 to press and position the nut member 07 and the preform 72, wherein the elastic positioning member 62 can adopt a rhombus structure with one end open made by bending a metal rod, and adopt other replaceable forms that can be clamped between two V-shaped grooves.

[0039] The prepared type I connecting strip plate 10, L-shaped connecting strip plate 20, and Z-shaped connecting strip plate 30 can be selected and applied as needed. Figure 1 As shown, it is mainly used for connecting profiles with no step difference requirements or large curvature radius (exceeding R200), such as large curvature radius or plane docking area of ​​the front and rear edges of the wing. In this case, the plate 1 02 to be connected and the plate 2 03 to be connected are arranged in the same plane, and a type of connecting strip 10 is placed against the connecting position of the plate 1 02 to be connected and the plate 2 03 to be connected. The corresponding positions of the plate 1 02 to be connected and the plate 2 03 to be connected are processed with perforations 04, and then fastened with the connecting components by bolts 01, so that the plate 1 02 to be connected and the plate 2 03 to be connected are connected and fixed by the type of connecting strip 10; the application of the L-type connecting strip 20 and the Z-type connecting strip 30 is the same as the same type of connecting strip 10, the difference is: combined with Figure 2 As shown, the L-shaped connecting strip 20 is mainly used to connect the profiles arranged at an angle. Figure 3 As shown, the Z-shaped connecting strip 30 is mainly used for profiles with step difference requirements, and when the Z-shaped connecting strip 30 connects the connecting plate 1 02 and the plate 2 03 to be connected, fine-tuning can be performed by adding pads 05 of different thicknesses.

[0040] like Figure 5 to Figure 11 As shown, a molding method of a composite material lightweight connecting strip plate structure comprises the following steps:

[0041] Step 1: Select a thermoplastic composite laminated plate 70 according to the use requirements of the type I connecting strip 10, the L-shaped connecting strip 20 or the Z-shaped connecting strip 30. For the type I connecting strip 10, the thermoplastic composite laminated plate 70 is directly cut and blanked to obtain a type I preform 72. For the L-shaped connecting strip 20 or the Z-shaped connecting strip 30, the thermoplastic composite laminated plate 70 is pressed and formed by the corresponding hot pressing tool 71 to obtain an L-shaped or Z-shaped preform 72, and a margin of 5mm-10mm is left on the edge of the preform 72;

[0042] Step 2: According to the design dimensions, the edge of the preform 72 is machined to remove the excess, and then perforations 04 are processed at the connecting ends on both sides of the preform 72;

[0043] Step 3: Place the preform 72 after the perforation 04 is processed into an integrated injection mold for positioning. If the internal threaded insert 50 is selected as the connecting component, the internal threaded connecting ring 52 must be installed and placed at the same time. The molding surface 84 of the integrated injection mold is designed according to the configuration of the preform 72, and is provided with an injection channel 86 and a cavity for molding the injection shell 51 or the two injection frames 61;

[0044] Step 4: Feeding thermoplastic resin melt into the corresponding position inside the integrated injection mold through the injection channel 86 to prepare and mold the injection shell 51 or the two injection frames 61, and heating and pressurizing the integrated injection mold to achieve the integrated preparation of the internal threaded insert 50 or the nut slot 60 and the preform 72;

[0045] Step 5: After cooling, demolding is performed and the residual injection material is cut off. If the nut part 07 is selected as the connecting part, two V-shaped grooves need to be hollowed out and the nut part 07 and the preform 72 are pressed and positioned by the elastic positioning part 62 to obtain a composite material lightweight connecting strip plate structure.

[0046] Combination Fig. 9 As shown, the injection molding integrated combined mold includes a female mold 80 and a male mold 81 whose molding surface 84 matches the configuration of the preform 72. A positioning pin 83 is fixedly arranged at a position corresponding to the perforation 04 on the inner bottom surface of the female mold 80 for positioning the preform 72. An injection hole 85 is arranged on the top of the male mold 81. An injection channel 86 is arranged inside the male mold 81 and is connected to the injection hole 85. A cavity is arranged at the end of the injection channel 86. The cavity is divided into an embedded component injection cavity 82 corresponding to the injection molding shell 51 or a nut slot injection cavity corresponding to the two injection molding frames 61 according to the selection of the connecting parts. In addition, the injection channel 86 of the injection molding integrated combined mold also extends to the connecting ends on both sides of the preform 72, and can form a plate end injection molding edge 87 at both ends of the preform 72 during the thermoplastic resin melt injection molding process.

[0047] Among them, the height of the positioning pin 83 is preferably 5mm-10mm greater than the depth of the perforation 04. The thermoplastic resin material can be polypropylene PP, polycarbonate PC, polyetherimide PEI, nylon PA66, polyphenylene sulfide PPS, polyaryletherketone polymer PAEK, etc., and the injection molding operation is performed by an injection molding machine. The thermoplastic resin pellets (which can be further mixed with short-term fibers for reinforcement) can be heated and mixed by the injection molding machine to make the material reach above the melting temperature, and then transported to the injection hole 85 through the nozzle.

[0048] It will be apparent to those skilled in the art that the invention is not limited to the details of the exemplary embodiments described above and that the invention can be implemented in other forms of assembly without departing from the spirit or essential features of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive, and the scope of the invention is defined by the appended claims rather than the foregoing description, and it is intended that all variations within the meaning and range of equivalents of the claims be included in the invention. Any reference numeral in a claim should not be considered as limiting the claim to which it relates.

[0049] In addition, it should be understood that although the present specification is described according to implementation modes, not every implementation mode contains only one independent technical solution. This description of the specification is only for the sake of clarity. Those skilled in the art should regard the specification as a whole. The technical solutions in each embodiment may also be appropriately combined to form other implementation modes that can be understood by those skilled in the art.

Claims

1. A composite material lightweight connecting strip plate structure, using a type I connecting strip plate (10), an L-shaped connecting strip plate (20) or a Z-shaped connecting strip plate (30), characterized in that: The connecting strip plate structure body adopts a thermoplastic composite laminated flat plate (70) as a preform (72) of a type or is prepared by a corresponding hot pressing molding tool (71) to obtain an L-shaped or Z-shaped preform (72). The connecting ends on both sides of the preform (72) are respectively processed and provided with a plurality of perforations (04) along the width direction. While the preform (72) is hot pressed and solidified, a connecting component that cooperates with a bolt (01) is formed at the outer end of each perforation (04) to form a connecting strip plate structure as a whole. The connecting component is an internal threaded embedded part (50) or a nut part (07). When the internal threaded embedded part (50) is used, the internal threaded embedded part (50) is coaxially attached to the perforation (04) by an internal threaded connecting ring (52) and is hot pressed. During solidification, a thermoplastic resin melt is used to form an injection molded shell (51) on the outside of the nut (07) and the preform (72) as a whole. When the nut (07) is used, two injection molded frames (61) are formed integrally on both sides of the through hole (04) by the thermoplastic resin melt during hot pressing solidification. A nut clamping groove (60) is formed between the two injection molded frames (61), and two V-shaped grooves are hollowed out relatively at the middle positions of the inner sides of the two injection molded frames (61). The nut (07) is coaxially attached to the through hole (04). A rectangular positioning wing is integrally provided around the nut (07) and is clamped in the nut clamping groove (60). The elastic positioning member (62) is clamped between the two V-shaped grooves to press and position the nut (07) and the preform (72).

2. A composite material lightweight connecting strip plate structure according to claim 1, characterized in that: The connecting ends on both sides of the preform (72) are respectively cut between each two adjacent through holes (04) to remove excess to form a toothed structure (06).

3. A composite material lightweight connecting strip plate structure according to claim 1, characterized in that: The outer wall of the internal thread connection ring (52) adopts a stepped structure.

4. A composite material lightweight connecting strip plate structure according to claim 1, characterized in that: The elastic positioning member (62) is a diamond-shaped structure with one end open and made by bending a metal rod.

5. The composite light-weight connecting strip plate structure according to claim 1, characterized in that: The thermoplastic composite laminated plate (70) is reinforced with continuous fibers.

6. A method for forming a composite light-weight connecting strip plate structure, characterized in that: According to claim 1, the composite material lightweight connecting strip plate structure, the molding method thereof comprises the following steps: Step 1: Select a thermoplastic composite laminated plate (70) according to the use requirements of a type I connecting strip (10), an L-shaped connecting strip (20) or a Z-shaped connecting strip (30); for the type I connecting strip (10), directly cut the thermoplastic composite laminated plate (70) to obtain a type I preform (72); for the L-shaped connecting strip (20) or the Z-shaped connecting strip (30), press the thermoplastic composite laminated plate (70) with a corresponding hot pressing tool (71) to obtain an L-shaped or Z-shaped preform (72), with margins left at the edges of the preform (72); Step 2: machining the edge of the preform (72) to remove excess excess according to the design dimensions, and then processing through holes (04) at the connecting ends on both sides of the preform (72); Step 3: Place the preform (72) that has been punched (04) into an integrated injection mold for positioning. If an internal threaded insert (50) is selected as a connecting component, an internal threaded connecting ring (52) must also be installed and placed at the same time. The molding surface (84) of the integrated injection mold is designed according to the configuration of the preform (72), and is provided with an injection channel (86) and a cavity for molding an injection molded shell (51) or two injection molded frames (61); Step 4: feeding a thermoplastic resin melt into a corresponding position inside the integrated injection mold through the injection channel (86) to prepare and mold the injection shell (51) or the two injection frames (61), and heating and pressurizing the integrated injection mold to achieve integrated preparation of the internal thread insert (50) or the nut slot (60) and the preform (72); Step 5: After cooling, demoulding is performed and the residual injection material is cut off. If the nut part (07) is selected as the connecting part, two V-shaped grooves need to be hollowed out and the nut part (07) and the preform (72) are pressed and positioned by the elastic positioning part (62), so as to obtain a composite material lightweight connecting strip plate structure.

7. The method for forming a composite material lightweight connecting strip plate structure according to claim 6, characterized in that: The injection molding integrated combined mold comprises a female mold (80) and a male mold (81) whose molding surface (84) matches the configuration of the preform (72); a positioning pin (83) is fixedly arranged at a position corresponding to the perforation (04) on the inner bottom surface of the female mold (80) for positioning the preform (72); an injection hole (85) is arranged on the top of the male mold (81); an injection channel (86) is arranged inside the male mold (81) and is connected to the injection hole (85); a cavity is arranged at the end of the injection channel (86); and the cavity is divided into an embedded component injection cavity (82) corresponding to the injection molding shell (51) or a nut slot injection cavity corresponding to the two injection molding frames (61) according to the selection of the connecting component.

8. The method for forming a composite material lightweight connecting strip plate structure according to claim 7, characterized in that: The injection channel (86) of the integrated injection mold also extends to the connecting ends on both sides of the preform (72), and can form plate end injection molding edges (87) at both ends of the preform (72) during the thermoplastic resin melt injection molding process.

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