Thermal folding forming method and device for additive manufacturing of three-dimensional lattice structure of fiber-reinforced composite

Abstract

A thermal folding forming method for additive manufacturing of a three-dimensional lattice structure of a fiber-reinforced composite, the method comprising the following specific steps: a first step, printing a fiber-reinforced composite having a repeated two-dimensional planar lattice structure by means of a dual-nozzle continuous fiber-reinforced composite additive manufacturing apparatus; a second step, using a robotic arm gripper (4) to grip the printed fiber-reinforced composite having a two-dimensional planar lattice structure and place same onto a retractable hot roller thermal folding and heating device, and heating same at a fiber connection point, wherein the thermal folding device is arranged in a 10 x 10 columnar lattice and can be fully retracted with a retractable height ranging from 0-50 mm, such that the fiber-reinforced composite having a two-dimensional planar lattice structure is heated and elevated by means of the retractable hot roller, and can be folded into the fiber-reinforced composite having a three-dimensional lattice structure; and a third step, using the robotic arm gripper (4) to grip the fiber-reinforced composite having a three-dimensional lattice structure and place same into a water-cooling box for water cooling and shape setting. The forming method can improve the structural complexity of the fiber-reinforced composite, thereby achieving the three-dimensional structure transformation of the composite.

Description

Additive manufacturing hot folding forming method and device for three-dimensional lattice structure of fiber composite material TECHNICAL FIELD

[0001] The present application relates to the technical field of additive manufacturing, in particular to a method and device for rapidly forming a three-dimensional lattice structure of thermoplastic fiber composite material by additive manufacturing hot folding technology. BACKGROUND

[0002] Traditional grid structure composite materials are manufactured by traditional metal manufacturing methods, which have low shape control precision, low manufacturing efficiency and poor quality consistency, and therefore there is an urgent need to develop automated and digital manufacturing means. Traditional preparation is mainly carried out by subtractive methods such as traditional cutting processing, laser processing, electric spark (wire cutting) processing and electrolytic processing on titanium alloy and other metal plates, which has great difficulty in material processing, and it is difficult to control the shape of the grid cell. Attempts are being made to use fiber composite materials instead, but due to the fine unit structure and complex overall structure, it is difficult to use common automatic production processes such as weaving, winding and laying to prepare the grid structure due to the complex structure of the grid structure with thin walls and multiple openings. The traditional forming process using fiber composite materials such as manual laying is complex, the mold development cycle is long, and the complexity of the parts is limited, which seriously restricts the rapid development and batch production of fiber composite materials.

[0003] Additive manufacturing has the advantages of digitalization, moldless and flexibility, and can realize integrated rapid forming of composite components. By creating a product model on a computer and using layer-by-layer manufacturing and layer-by-layer printing, it can realize the rapid three-dimensional forming of any geometric shape object. Compared with traditional manufacturing, additive manufacturing of composite materials has the advantages of high design freedom, low production cost for small batches and high material efficiency.

[0004] Due to the layer-by-layer forming principle of additive manufacturing, three-dimensional lattice structures lack forming pressure in the Z direction, cannot be printed in midair, and are difficult to form complex three-dimensional structures. Based on the chemical properties of thermoplastic resin-based composite materials that can be deformed above the melting point, the hot folding process can realize the lossless conversion of two-dimensional lattice structures to three-dimensional lattice structures. SUMMARY

[0005] To solve the above problems, the present application discloses a method for rapidly forming a two-dimensional planar lattice structure of fiber composite material using additive manufacturing technology, and a lossless manufacturing of a three-dimensional lattice structure based on the two-dimensional planar lattice structure using additive manufacturing hot folding technology, which realizes the collaborative manufacturing of complex topography and three-dimensional structure of the grid lattice structure.

[0006] An additive manufacturing hot folding forming method for a three-dimensional lattice structure of fiber composite material, comprising the following steps:

[0007] Step one, using a double nozzle continuous fiber composite material additive manufacturing equipment to print fiber composite material with repeated two-dimensional planar dot matrix structure;

[0008] Step two, using a mechanical arm gripper to place the printed continuous fiber thermoplastic composite planar structure on a telescopic hot roller heat folding heating device, and by heating the fiber connection site through the telescopic hot roller heat folding heating device, the telescopic hot roller heat folding heating device has a 10x10 columnar square arrangement, the telescopic height range is 0-50mm, and the two-dimensional planar dot matrix structure fiber composite material is heated and raised by the telescopic hot roller, and is folded into a three-dimensional dot matrix structure fiber composite material;

[0009] Step three, using a mechanical arm gripper to place the three-dimensional dot matrix structure fiber composite material in a water cooling box for water cooling and setting.

[0010] Further, the printer used in step one is a continuous fiber double nozzle printer, which can switch between double nozzle printing, printing pure resin material, short fiber composite material, and continuous fiber composite material.

[0011] Further, the mechanical arm gripper used in step two is two, which can freely move and grab the left and right ends of the two-dimensional planar dot matrix structure fiber composite material, and keep the horizontal stability of the planar structure.

[0012] Further, the telescopic hot roller heat folding heating device in step two is composed of 10x10 telescopic devices at the bottom and 10x10 columnar aluminum alloy square arrays at the top, the columnar aluminum alloy has a size of 10x10x100mm, the telescopic device can realize the up and down telescoping of the columnar aluminum alloy column, and the telescopic size is 0-50mm; the upper end of the columnar aluminum alloy column is a heating roller with a diameter of 2mm, and the heating temperature range is 20℃-400℃.

[0013] Further, the water cooling box in step three is located behind the telescopic hot roller heat folding heating device, which is used for rapid cooling and setting of the three-dimensional structure fiber composite material.

[0014] Further, the process is an automatic assembly line process, and the mechanical arm gripper can freely move between the continuous fiber composite material multi-nozzle printer, the telescopic hot roller heat folding heating device, and the water cooling box.

[0015] The application discloses a kind of three-dimensional lattice structure of fiber composite material of additive manufacturing hot folding forming device, including double nozzle fiber composite material additive manufacturing equipment, mechanical arm, telescopic hot roller hot folding device, water-cooling tank four parts, through the mechanical arm grabbing two-dimensional plane lattice structure fiber composite material of additive manufacturing, through telescopic hot roller heat folding treatment, two-dimensional plane lattice structure can be changed into three-dimensional lattice structure, while water-cooling tank is cooled and shaped;Through telescopic hot roller heat folding treatment, two-dimensional plane lattice structure can be changed into three-dimensional lattice structure, while water-cooling tank is cooled and shaped, can improve the complexity of structure of workpiece, realize additive manufacturing three-dimensional complex structure.

[0016] Further, the mechanical arm includes a mechanical arm gripper, a mechanical arm movement shaft, a mechanical arm rotating mechanism and a mechanical arm fixed base; the top of the mechanical arm fixed base is connected to the mechanical arm rotating mechanism, and the mechanical arm rotating mechanism is connected to the mechanical arm gripper through the mechanical arm movement shaft.

[0017] Further, the telescopic device is placed in the hot folding telescopic container; the bottom of the aluminum alloy column is connected to the telescopic device, and the top is connected to the heating roller; the telescopic hot roller hot folding device includes a plurality of arrayed telescopic devices, aluminum alloy columns, hot folding telescopic containers and heating rollers; the telescopic device is placed in the hot folding telescopic container; the bottom of the aluminum alloy column is connected to the telescopic device, and the top is connected to the heating roller; the hot plastic composite material fixing point can be changed to different heights at different heights, and a three-dimensional structure is formed.

[0018] The application has the following beneficial effects:

[0019] 1. The mechanical arm and the telescopic hot roller hot folding heating device can quickly change the two-dimensional plane lattice structure of the fiber composite material into a three-dimensional lattice structure, and the mechanical arm can grab the plane material to keep the material stable during the hot folding deformation process without position deviation.

[0020] 2. The telescopic hot roller can change the height of the three-dimensional structure by adjusting the telescopic height of the three-dimensional column. The heating temperature of the telescopic hot roller can be adjusted, and different hot folding temperatures can be used for different thermoplastic materials without damaging the materials. The elongation height of the hot folding heating roller is calculated according to the angle of the expected folding of the Z plane according to the Pythagorean theorem. BRIEF DESCRIPTION OF DRAWINGS

[0021] FIG. 1 is a schematic diagram of a three-dimensional lattice structure of fiber composite material of additive manufacturing hot folding forming device.

[0022] FIG. 2 is a flow chart of a three-dimensional lattice structure of fiber composite material of additive manufacturing hot folding forming device.

[0023] FIG. 3 is a schematic diagram of a hot folding embodiment.

[0024] Figure 4a is a three-dimensional view of a telescopic hot roller.

[0025] Figure 4b is a top view of the telescopic hot roller.

[0026] Figure 5a is a schematic view of a telescopic device for hot folding.

[0027] Figure 5b is a top view of the hot folding telescopic container.

[0028] Figure 1 is a schematic view of a hot folding forming device for additive manufacturing of a three-dimensional lattice structure of a fiber composite material. DETAILED DESCRIPTION

[0029] The present application will be further clarified by the following description and specific embodiments, which should be understood not to limit the scope of the application. It should be noted that the terms "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to the directions in the drawings, and the terms "inner" and "outer" refer to the directions towards or away from the geometric center of a particular component.

[0030] Referring to Figure 1, the present embodiment provides a schematic view of a hot folding forming device for additive manufacturing of a three-dimensional lattice structure of a fiber composite material.

[0031] As shown in Figures 4a, 4b, 5a, and 5b, the hot folding forming device for additive manufacturing of a three-dimensional lattice structure of a fiber composite material of the present embodiment comprises, in sequence, a hot bed 3, a mechanical arm fixing base 7, a hot folding telescopic container 10, a water cooling device 12, and a mechanical arm fixing base 7; the hot bed 3 is provided with two printing nozzles 2 above; the printing filament 1 is printed into a two-dimensional planar lattice structure of a fiber composite material on the hot bed 3 through the printing nozzles 2; each mechanical arm fixing base 7 is connected with a mechanical arm motion shaft 5 through a mechanical arm rotating mechanism 6; the end of the mechanical arm motion shaft 5 is connected with a mechanical arm gripper 4,

[0032] The two-dimensional planar lattice structure of a fiber composite material manufactured by additive manufacturing is grabbed by the mechanical arm gripper 4, and is subjected to hot folding treatment by the telescopic hot roller, so that the two-dimensional planar lattice structure is changed into a three-dimensional lattice structure, and the water cooling device 12 is used for cooling and shaping.

[0033] The telescopic hot roller hot folding device comprises a plurality of arrayed telescopic devices 11, an aluminum alloy column 9, a hot folding telescopic container 10, and a heating hot roller 8. The telescopic device 11 is placed in the hot folding telescopic container 10; the bottom of the aluminum alloy column 9 is connected with the telescopic device 11, and the top is connected with the heating hot roller 8.

[0034] Referring to FIG. 3, the embodiment provides a two-dimensional planar lattice structure which is changed into a three-dimensional lattice structure through heat folding. The precise manufacturing of components which are difficult to be shaped by traditional manufacturing processes is achieved.

[0035] Step one, a double-nozzle continuous fiber composite material additive manufacturing equipment is used to print a thin-walled lattice grid with a two-dimensional planar lattice structure, the grid size is 10*10, a total of 100 grids, the grid cell size is 10*10mm, and the wall thickness is 2mm;

[0036] Step two, a mechanical arm gripper is used to place the printed continuous fiber composite material thin-walled lattice grid structure on a telescopic heat roller heat folding heating device, and the fiber connection points in the 2nd, 4th, 6th, 8th and 10th rows from left to right in the vertical direction are heated. The heat folding device is arranged in 10*10 columnar grids and can be completely telescopic. In the embodiment, the heat folding device is set to be stretched upward by 5mm, and the thin-walled lattice grid structure forms a 30° angle with the Z-direction plane. The thin-walled lattice grid structure is heated and raised by the telescopic heat roller, and the point is raised upward, which can be folded into a three-dimensional pyramid structure; step three, a mechanical arm gripper is used to place the three-dimensional pyramid structure of the fiber composite material in a water cooling box for water cooling and setting.

[0037] The technical means disclosed in the scheme of the application is not limited to the technical means disclosed in the above-mentioned embodiments, and also includes technical solutions composed of any combination of the above technical features.

Claims

1. A method of additive manufacturing of a three-dimensional lattice structure of a fiber composite material by hot folding, characterized in that, The method comprises the following steps: Step 1: printing a fiber composite material with a repeated two-dimensional planar dot matrix structure by using a double-nozzle continuous fiber composite material additive manufacturing equipment; Step 2: placing the printed continuous fiber thermoplastic composite planar structure on a telescopic hot roller heat folding heating device by using a mechanical arm gripper, heating the fiber connection site by the telescopic hot roller heat folding heating device, the hot telescopic rod mechanism on the telescopic hot roller heat folding heating device is arranged in a 10x10 columnar square grid, the telescopic height range is 0-50mm, the two-dimensional planar dot matrix structure fiber composite material is heated and raised by the telescopic hot roller, and is folded into a three-dimensional dot matrix structure fiber composite material; Step 3: placing the three-dimensional dot matrix structure fiber composite material in a water-cooled box and cooling and setting by using a mechanical arm gripper.

2. A method of additive manufacturing of a three-dimensional lattice structure of a fibre composite material by hot folding, according to claim 1, characterized in that: The printer used in step 1 is a continuous fiber double-nozzle printer, which can switch between double-nozzle printing, printing pure resin material, short fiber composite material and continuous fiber composite material.

3. A method of additive manufacturing of a three-dimensional lattice structure of a fiber composite material by hot folding according to claim 1, characterized in that The mechanical arm gripper used in step 2 is two, which can freely move and grab the left and right ends of the two-dimensional planar dot matrix structure fiber composite material, and keep the horizontal stability of the planar structure.

4. A method of additive manufacturing of a three-dimensional lattice structure of a fiber composite material by hot folding according to claim 1, characterized in that The telescopic hot roller heat folding heating device in step 2 is composed of 10x10 telescopic devices at the lower part and 10x10 columnar aluminum alloy square arrays at the upper part, the columnar aluminum alloy has a size of 10x10x100mm, the telescopic device can realize the up-down telescopic movement of the columnar aluminum alloy column, and the telescopic size is 0-50mm; the upper end of the columnar aluminum alloy column is a heating roller with a diameter of 2mm, and the heating temperature range is 20-400℃.

5. The method of claim 1, wherein the method is a method of additive manufacturing of a three-dimensional lattice structure of fiber composites by hot folding, characterized in that The water-cooled box in step 3 is located behind the telescopic hot roller heat folding heating device, and is used for rapidly cooling and setting the three-dimensional structure fiber composite material.

6. The method of claim 1, wherein the method is a method of additive manufacturing of a three-dimensional lattice structure of fiber composites by thermal folding, characterized in that: The process is an automatic assembly line process, and the mechanical arm gripper can freely move among the continuous fiber composite material multi-nozzle printer, the telescopic hot roller heat folding heating device and the water-cooled box.

7. An additive manufacturing thermal folding forming apparatus for three-dimensional lattice structures of fiber composites, characterized by: The method comprises a double-nozzle fiber composite material additive manufacturing equipment, a mechanical arm, a telescopic hot roller heat folding device and a water-cooled box, the two-dimensional planar dot matrix structure fiber composite material manufactured by the mechanical arm is heat-folded by the telescopic hot roller, so that the two-dimensional planar dot matrix structure is changed into a three-dimensional dot matrix structure, and the water-cooled box is cooled and set.

8. An additive manufacturing thermal folding forming apparatus for a fibre composite three-dimensional lattice structure according to claim 7, characterised in that: The mechanical arm comprises a mechanical arm gripper, a mechanical arm movement shaft, a mechanical arm rotating mechanism and a mechanical arm fixed base; the top of the mechanical arm fixed base is connected with the mechanical arm rotating mechanism, and the mechanical arm rotating mechanism is connected with the mechanical arm gripper through the mechanical arm movement shaft.

9. An additive manufacturing thermal folding forming apparatus for a three-dimensional lattice structure of a fiber composite material according to claim 7, characterized in that: The telescopic device is placed in the heat folding telescopic container; the bottom of the aluminum alloy column is connected with the telescopic device and the top is connected with the heating roller; the telescopic hot roller heat folding device comprises a plurality of arrayed telescopic devices, aluminum alloy columns, heat folding telescopic containers and heating rollers; the telescopic device is placed in the heat folding telescopic container; the bottom of the aluminum alloy column is connected with the telescopic device and the top is connected with the heating roller.

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