Spray head embedded type 3D printing equipment for thermosetting wood-plastic composite material

Abstract

A nozzle embedded type 3D printing device for a thermosetting wood-plastic composite material belongs to the technical field of 3D printing, and comprises a rack, and an extrusion movement mechanism, a powder laying mechanism, a powder bed mechanism, a printing platform movement mechanism and a binder feeding system which are arranged on the rack, and the extrusion movement mechanism is fed through the feeding system. The printing efficiency of existing printing equipment can be improved, the manufacturing and maintenance cost of the existing equipment is reduced, the accuracy and consistency of a printing structure are ensured, and printing of a high-precision complex structure is achieved; the provided equipment combines the advantages of extrusion type printing equipment and a powder bed structure, the requirement of single extrusion printing for the formability of extruded materials is met, controllable printing of large-flow, high-viscosity and large-layer-thickness printing shapes and precision is achieved, the equipment is suitable for various types of binder materials, the variety and size range of powder bed materials is large, and the equipment is suitable for large-flow, high-viscosity and large-layer-thickness printing. And the rapid part forming machining requirements of wide material application range, large forming size and high part strength are met.

Description

Technical Field

[0001] The invention belongs to the technical field of 3D printing, and relates to a 3D printing device for wood-plastic composite materials, and in particular to a nozzle embedded 3D printing device for thermosetting wood-plastic composite materials. Background Art

[0002] Existing 3D printing equipment for wood-plastic composite materials mainly includes three types: fused deposition equipment, selective laser sintering equipment and bonding jet equipment. When the fused deposition equipment is working, it includes processes such as heating the nozzle to melt the material and maintaining the temperature of the printing bed to promote material adhesion, which reduces the printing speed. In addition, the model slice data of this type of equipment contains a lot of filling information and support structure data, which seriously reduces the printing efficiency. The selective laser sintering equipment uses a powder spreading device to spread the powder material on the workbench, and then uses the thermal effect of the laser beam to sinter and melt the powder in the target area, and then adheres and accumulates layer by layer without the need for a support structure, which improves the printing efficiency to a certain extent. However, the precision parts of this equipment lead to high manufacturing and maintenance costs, and wood-plastic composite materials have high requirements for the temperature and laser power control of the equipment. The bonding jet equipment does not require a laser system, which reduces the manufacturing and maintenance costs of the equipment. However, in the process of high-speed and high-throughput printing, the collision of droplets with the powder bed causes powder splashing, which easily leaves gaps inside the powder bed, further increasing the porosity of the printed parts, and causing the liquid to flow irregularly in the gaps of the powder bed, making it difficult to achieve high-precision printing of complex structures.

[0003] Therefore, in order to solve the problems of low printing efficiency, low printing accuracy and high equipment manufacturing and maintenance costs of existing printing equipment, a nozzle embedded 3D printing equipment suitable for wood-plastic composite powder (particles) is designed based on the in-situ impregnation principle to reduce powder splashing, reduce the number of high-cost parts, and achieve large-throughput rapid printing and molding of thermosetting wood-plastic composite materials. It has the ability to realize the whole process from material stacking to molding, and promote the sustainable development and industrial application of wood-plastic composite 3D printing technology. Summary of the invention

[0004] In order to overcome the problems existing in the prior art of 3D printing equipment of wood-plastic composite materials, such as low printing efficiency, low printing accuracy, high manufacturing and maintenance costs of the equipment, etc., the present invention designs a nozzle embedded 3D printing equipment, the nozzle is embedded in a powder bed mechanism containing wood-plastic composite materials, moves according to the designed path and injects a binder, the binder penetrates into the pores inside the printed part in the wood-plastic composite material, so that the wood-plastic composite material is bonded, and the material is initially solidified and formed at room temperature, and the 3D printing of the wood-plastic composite material is completed, and the mechanical properties of the printed part are improved through appropriate post-processing processes.

[0005] In order to achieve the purpose of the present invention, the technical solution adopted by the present invention is:

[0006] A nozzle embedded 3D printing device for thermosetting wood-plastic composite materials, the nozzle embedded 3D printing device comprises a frame, an extrusion motion mechanism, a powder spreading mechanism, a powder bed mechanism, a printing platform motion mechanism and a binder feeding system, wherein the frame is provided with an extrusion motion mechanism, a powder spreading mechanism, a powder bed mechanism and a printing platform motion mechanism. Specifically:

[0007] The extrusion motion mechanism includes synchronous belt module guide rail Ⅰ1, synchronous belt module guide rail Ⅱ3, synchronous belt module guide rail Ⅲ6, synchronous belt module guide rail Ⅳ10, slider 2, nozzle 4, servo motor Ⅰ5, servo motor Ⅱ7, servo motor Ⅲ9, transmission shaft Ⅰ8 and motor cage 23. Specifically: the synchronous belt module guide rail Ⅰ1 and synchronous belt module guide rail Ⅳ are installed in parallel on the left and right sides of the top of the frame, the sliders on the two synchronous belt module guide rails Ⅰ1 are directed upward, and the power shafts of the two synchronous belt module guide rails Ⅰ1 are connected by a transmission shaft Ⅰ8. The servo motor Ⅲ9 cooperates with the motor cage 23 to be installed above the right synchronous belt module guide rail Ⅰ1 to provide power for its slider 2 to move in the front and rear direction. A synchronous belt module guide rail Ⅱ3 is installed above the two sliders of the synchronous belt module guide rail Ⅰ1, and the slider of the synchronous belt module guide rail Ⅱ3 is directed forward. The servo motor Ⅱ7 cooperates with the motor cage 23 to be installed on the right side of the synchronous belt module guide rail Ⅱ3 to provide power for its slider to move in the left and right directions. A synchronous belt module guide rail III 6 is vertically installed on the slider of the synchronous belt module guide rail II 3, and a servo motor I 5 is installed on the top of the synchronous belt module guide rail III 6 to provide power for the vertical movement of its slider. The nozzle 4 is installed above the slider of the synchronous belt module guide rail III 6 to cooperate with the printing platform 29 to move up and down, that is, to realize the three-axis movement of the nozzle 4 on the frame and realize the printing process according to the specified path.

[0008] Furthermore, the sliders 2 of the two synchronous belt module guide rails Ⅰ1 are both installed with brackets 22 for installing the synchronous belt module guide rails Ⅱ3.

[0009] The powder spreading mechanism includes a connecting plate 11, a synchronous belt module V12, a powder bin 13, a hopper 37, a synchronous belt module VI14, a scraper 35 and a servo motor V36. The synchronous belt module guide rails V12 and VI14 are installed horizontally on the rear side of the frame, and the slider is facing forward. A connecting plate 11 is installed on the two sliders to synchronize the movement. The connecting plate 11 helps the powder bin 13 to resist the bending moment; the servo motor V36 is installed on the rear side of the connecting plate 11 to provide power for the movement of the slider. The powder bin 13 is installed on the connecting plate 11, and the hopper 37 and the scraper 35 are stacked on it. The scraper 35 is installed below the hopper 37 and is used to scrape the powder filled on the printing plane flat, that is, during the movement of the powder bin 13, a layer of powder is spread on the printing platform 29 and is flattened by the scraper 35.

[0010] The powder bed mechanism includes a positioning pin 16, an aluminum plate 24, a positioning pin frame 27, a powder bed positioning frame 28 and a printing platform 29. The outer wall of the powder bed mechanism is composed of four aluminum plates 24, and the bottom surface of the powder bed mechanism is a movable printing platform 29. Rollers are installed at the bottom of the powder bed mechanism, which are pushed into the working position. The positioning pin frame 27 and the powder bed positioning frame 28 on the rear side of the powder bed mechanism are connected using positioning pins 26 to complete the positioning of the powder bed mechanism. An electromagnet 30 is installed at the bottom of the powder bed mechanism. When the electromagnet 30 and the electromagnet installed on the lifting platform 29 are energized, adsorption is completed, and then the two locks on the front side of the powder bed mechanism are locked to fix the powder bed mechanism.

[0011] Furthermore, in the powder bed mechanism: two adjacent aluminum plates 24 in the outer wall of the powder bed mechanism are fixed by inner corner aluminum 25 and outer corner aluminum 15; felt is installed between the printing platform 29 and the outer wall of the powder bed mechanism to prevent powder leakage; multiple pulleys 21 are installed on the aluminum profiles on both sides of the powder bed mechanism to facilitate the installation and disassembly of the powder bed mechanism before and after printing; a lock 20 is installed between the front aluminum plate 24 of the powder bed mechanism and the gap of the aluminum profile for fixing the powder bed mechanism.

[0012] The printing platform motion mechanism includes a servo motor IV 32, a ball screw 18, a transmission shaft II 19, a conveyor belt, a lifting platform 34, an electromagnet 30, and an electromagnet mounting platform 28. The servo motor IV 32 rotates, and transmits power to the pulleys 17 on both sides through the conveyor belt. The pulleys provide power for the ball screw 18, thereby driving the printing platform 29 to move vertically on the ball screw, and realizing the layer-by-layer stacking of the printed model through the lifting platform 34. The four ball screws 18 shown are vertically installed on four aluminum profiles, and the lifting platform 34 is horizontally installed on the top. Four electromagnets 30 are installed around the lifting platform 34. When the electromagnets are energized, the printing platform 29 is fixed on the lifting platform 34. The servo motor IV 32 is installed on the aluminum profile between the two ball screws 18.

[0013] Furthermore, in the printing platform motion mechanism, the tension of the conveyor belt is adjusted by the tensioning wheel 33 to prevent failure of the belt transmission.

[0014] The adhesive feeding system includes a dispensing pressure tank A, a dispensing pressure tank B, a cleaning tank, a gear pump A, a gear pump B, a three-way ball valve, a DC motor and a dynamic mixing tube. The gas source outlet is connected to the gas inlets of the dispensing pressure tanks A and B through a pipeline, and the gas is added to the dispensing pressure tank A and the dispensing pressure tank B to maintain the pressure of the A glue in the dispensing pressure tank A and the B glue in the dispensing pressure tank B, which can improve the rheological properties of the glue and improve its adhesion and bonding strength. The gas source outlet is connected to the gas inlet of the cleaning tank through a pipeline, and the gas is added to the cleaning tank to squeeze out the cleaning agent. The liquid outlet of the dispensing pressure tank A is connected to the inlet of the gear pump A through a pipeline, and the liquid outlet of the dispensing pressure tank B is connected to the inlet of the gear pump B. The amount and ratio of the A glue and the B glue can be accurately controlled by the control of the gear pump by the servo motor. Use a three-way ball valve to connect the pipeline with controllable flow direction. The outlets of gear pump A and gear pump B are connected to one valve port of two three-way ball valves respectively. Two three-way ball valves are installed on the diverter with one valve port respectively. Two three-way ball valves are connected to the dynamic mixing tube with one valve port respectively. The liquid outlet of the cleaning tank is connected to a tee, and the other two outlets of the tee are connected to the diverter with a pipeline to pressurize the cleaning agent and deliver it to the pipeline. The two pipelines can increase the flow rate of the cleaning agent. A DC motor is installed at the top of the diverter and connected to the auger in the dynamic mixing tube through a coupling. The inlet of the dynamic mixing tube is installed at the lower end of the diverter to fully mix glue A and glue B into a binder. When the valves of glue A and glue B are opened and the valve of the cleaning tank is closed, glue A and glue B enter the dynamic mixing tube. The outlet of the dynamic mixing tube is connected to the nozzle, and the DC motor drives the auger to rotate to improve the uniformity of the adhesive mixing. When the valves of glue A and glue B are closed and the valve of the cleaning tank is opened, the cleaning agent is sprayed out along the pipeline to achieve the effect of cleaning the pipeline and the dynamic mixing tube. The DC motor is turned on during cleaning to improve the cleaning effect. The outlet of the dynamic mixing tube is connected to the inlet of the nozzle 4 through a pipeline, which is used to transport the adhesive to the nozzle 4, and the nozzle 4 extrude the adhesive to achieve printing.

[0015] A method for using a nozzle embedded 3D printing device for thermosetting wood-plastic composite materials comprises the following steps:

[0016] First, the printing plane 29 is adjusted to the zero point, and the powder bed mechanism is pushed into the specified position along the pulley 21. Then, the positioning pin 16 is passed through the holes of the positioning pin frame 27 and the powder bed positioning frame 28, the lock buckle 20 is locked, and the electromagnet 30 is energized to adsorb the printing plane 29 on the lifting plane 34 to complete the positioning of the powder bed mechanism; then, the model made according to the computer-aided design is sliced ​​and imported into the PC control terminal, and the control terminal sends the command to the PLC through the upper computer software; then, the motion controller controls the servo motor I5, servo motor II7, servo motor III9, servo motor IV32, and servo motor V36 to perform three-dimensional spatial motion through the extrusion motion mechanism and the printing platform motion mechanism;

[0017] Secondly, the air source is added to the dispensing pressure tank A and the dispensing pressure tank B to maintain the pressure of glue A and glue B. When the valves of glue A and glue B are opened and the valve of the cleaning tank is closed, the gear pump is used to pump glue A and glue B into the dynamic mixing tube, and the DC motor drives the auger to rotate to improve the uniformity of the adhesive mixing. The outlet of the dynamic mixing tube is connected to the nozzle 4 to extrude the adhesive.

[0018] Again, while the extrusion mechanism drives the nozzle 4 to move, the nozzle 4 extrude the material, while the powder bin 13 moves, the powder flows out from the gap of the powder bin 13 to the printing plane 29, and the powder is flattened under the action of the scraper 35, so that the material is stacked in the process of continuous movement and spraying; then after a long period of printing, the part printing is completed. The electromagnet 30 is powered off, the positioning pin 16 is removed, the lock 20 is opened, the powder bed mechanism is removed, and the printed part is removed for post-processing.

[0019] Finally, close the A glue and B glue valves, open the cleaning tank valve, and spray the cleaning agent along the pipeline to achieve the effect of cleaning the pipeline and the dynamic mixing tube. Turn on the DC motor during cleaning to improve the cleaning effect.

[0020] Compared with the prior art, the beneficial effects of the present invention are:

[0021] (1) The equipment provided by the present invention solves the problems of low printing efficiency of existing wood-plastic composite material printing equipment and high manufacturing and maintenance costs of laser sintering equipment. It has the ability to realize the entire process from material stacking to molding, and reduces powder splashing during the printing process.

[0022] (2) During the 3D printing process of the present invention, the embedded printing nozzle is buried to a certain depth below the plane of the printing powder bed and squeezes out the liquid binder, forming a channel of a certain depth and width on the surface of the powder bed. Simultaneously, a large flow of liquid binder instantly fills the dynamic channel. Thereafter, the liquid binder penetrates, diffuses, and solidifies in a controlled and constrained state to form a printed entity, thereby ensuring the accuracy and consistency of the printed structure and achieving high-precision printing of complex structures.

[0023] (3) The device provided by the present invention combines the advantages of extrusion printing equipment and powder bed structure, solves the requirement of single extrusion printing on the formability of the extruded material, and realizes the controllable printing of the shape and precision of large flow, high viscosity and large layer thickness printing. The device is applicable to a wide variety of binder materials and a wide range of types and sizes of powder bed materials, meeting the needs of rapid prototyping of parts with wide material applicability, large molding size and high part strength. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0025] Figure 2 It is a schematic diagram of the extrusion motion mechanism of the present invention;

[0026] Figure 3 It is a schematic diagram of the powder spreading mechanism of the present invention;

[0027] Figure 4 Schematic diagram of the powder bed mechanism of the present invention Figure Ⅰ ;

[0028] Figure 5 Schematic diagram of the powder bed mechanism of the present invention Figure II ;

[0029] Figure 6 It is a top view of the powder bed mechanism of the present invention;

[0030] Figure 7 It is a schematic diagram of the lifting mechanism of the present invention;

[0031] Figure 8 It is a schematic diagram of the binder feeding system of the present invention;

[0032] In the figure: 1 synchronous belt module guide rail Ⅰ; 2 slider; 3 synchronous belt module guide rail Ⅱ; 4 nozzle; 5 servo motor Ⅰ; 6 synchronous belt module guide rail Ⅲ; 7 servo motor Ⅱ; 8 transmission shaft Ⅰ; 9 servo motor Ⅲ; 10 synchronous belt module guide rail Ⅳ; 11 connecting plate; 12 synchronous belt module guide rail Ⅴ; 13 powder bin; 14 synchronous belt module Ⅵ; 15 outer angle aluminum; 16 positioning pin; 17 pulley; 18 ball screw; 19 transmission shaft Ⅱ; 20 lock; 21 pulley; 22 bracket; 23 motor cage; 24 aluminum plate; 25 inner angle aluminum; 26 felt; 27 positioning pin rack; 28 powder bed positioning rack; 29 printing platform; 30 electromagnet; 31 pulley; 32 servo motor Ⅳ; 33 tensioning wheel; 34 lifting platform; 35 scraper; 36 servo motor Ⅴ; 37 hopper. DETAILED DESCRIPTION

[0033] The present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0034] The nozzle embedded 3D printing device for wood plastic composite materials, see Figures 1 to 8 , characterized in that the equipment includes a frame, an extrusion motion mechanism, a powder spreading mechanism, a powder bed mechanism, a printing platform motion mechanism and a binder feeding system.

[0035] The frames are all made of aluminum profiles connected by bolts.

[0036] The frame is provided with an extrusion motion mechanism, a powder spreading mechanism, a powder bed mechanism and a printing platform motion mechanism.

[0037] The extrusion motion mechanism includes a synchronous belt module guide rail Ⅰ1, a slider 2, a synchronous belt module guide rail Ⅱ3, a nozzle 4, a servo motor Ⅰ5, a synchronous belt module guide rail Ⅲ6, a servo motor Ⅱ7, a transmission shaft Ⅰ8, a servo motor Ⅲ9, a bracket 22 and a motor cage 23.

[0038] Install the synchronous belt module guide rail Ⅰ1 on the aluminum profile of the frame, with the slider 2 facing upwards, and install another synchronous belt module guide rail on the aluminum profile of the frame in parallel on the right side of the equipment. The power shafts of the two synchronous belt module guide rails are connected by a transmission shaft 8, so that the two sliders 2 move synchronously on the synchronous belt module guide rails; the motor cage 23 is installed on the rear end shaft of the right synchronous belt module guide rail, and the servo motor is installed above the right synchronous belt module guide rail and is connected to the motor cage by bolts to provide power for the slider to move forward and backward.

[0039] Bolt bracket 22 to install on slider 2. Install the same bracket above the slider of the right synchronous belt module to install synchronous belt module rail Ⅱ3. The slider is facing forward. The motor cage is installed on the right end shaft of synchronous belt module rail Ⅱ3. The servo motor is installed under the right synchronous belt module rail and connected to the motor cage by bolts to provide power for the slider to move left and right.

[0040] The synchronous belt module guide rail III 6 is vertically installed on the slider of the synchronous belt module guide rail II 3 , and the servo motor I 5 is installed on the upper end of the synchronous belt module guide rail III 6 to provide power for the slider to move up and down.

[0041] The nozzle 4 is installed on the slider of the synchronous belt module guide rail III 6, so that it can move up and down in coordination with the printing platform 29 to realize layer-by-layer stacking and molding of the printed model.

[0042] The powder bed mechanism includes an outer angle aluminum 15, a positioning pin 16, a lock 20, a pulley 21, an aluminum plate 24, an inner angle aluminum 25, a felt 26, a positioning pin frame 27, a powder bed positioning frame 28 and a printing platform 29.

[0043] Four aluminum plates 24 are fixed by outer angle aluminum 15 and installed as the outer wall of the powder bed mechanism; the printing platform 29 that can move up and down serves as the bottom surface of the powder bed mechanism; a felt 24 is installed between the printing platform 29 and the outer wall of the powder bed mechanism to prevent the powder from leaking from the gap; four inner angle aluminum 25 are installed on the inner side of the powder bed mechanism to prevent the felt from having poor sealing at the corners and causing the powder to leak at the corners. The powder bed mechanism installs multiple pulleys 21 on the aluminum profiles on both sides of the powder bed mechanism to facilitate the installation and disassembly of the powder bed mechanism before and after printing; two powder bed positioning frames 28 are installed on the rear side of the powder bed mechanism, and two positioning pin frames 27 are installed on the corresponding positions of the rear aluminum profiles. When the powder bed mechanism is installed to the specified position, the positioning pins 16 are passed through the holes of the positioning pin frames 27 and the powder bed positioning frames 28 to position the powder bed mechanism in the left and right directions; two lock buckles 20 are installed between the gaps between the aluminum plates and aluminum profiles on the front side of the powder bed mechanism to fix the powder bed mechanism.

[0044] The printing platform motion mechanism includes a ball screw 18 , a transmission shaft II 19 , an electromagnet mounting platform 28 , an electromagnet 30 , a pulley 31 , a servo motor IV 32 , a tensioning wheel 33 and a lifting platform 34 .

[0045] Four ball screws 18 are vertically mounted on four aluminum profiles, a lifting platform 34 is horizontally mounted on the top, and four electromagnets 30 are mounted around the lifting platform 34. When the electromagnets are powered, the printing platform 29 is fixed on the lifting platform 34. A servo motor IV 32 is mounted on the aluminum profile between two screws to provide power for the four ball screws. The power is transmitted through a belt drive and a transmission shaft 19 to enable the lifting platform to move up and down.

[0046] The powder spreading mechanism includes a connecting plate 11 , a synchronous belt module V12 , a powder bin 13 , a synchronous belt module VI14 , a scraper 35 and a servo motor V36 .

[0047] The synchronous belt module V12 and synchronous belt module VI14 are installed at the rear side of the frame, and the sliders are facing forward. The connecting plate 11 is installed above the two sliders for synchronous movement and resisting bending moment; the servo motor V36 is installed at the rear side of the connecting plate, and the servo shaft is connected to the right end shaft of the synchronous belt module V12 to provide power for the powder bin 13. The scraper 35 is installed below the hopper 37 to scrape the powder filled on the printing plane.

[0048] The use process of a nozzle embedded 3D printing device for thermosetting wood-plastic composite materials is as follows:

[0049] First, lift the printing plane 29 until it contacts the nozzle 4 outlet, use the outer angle aluminum 15 to fix the aluminum plate 24 as the outer wall of the powder bed, use the inner angle aluminum 25 and the felt 26 to seal the outer wall of the powder bed and the printing plane 29, push the powder bed mechanism into the specified position along the pulley 21, then pass the positioning pin 16 through the holes of the positioning pin frame 27 and the powder bed positioning frame 28, lock the lock 20, energize the electromagnet 30, adsorb the printing plane 29 on the lifting plane 34, and complete the positioning of the powder bed mechanism; then slice the model made according to the computer-aided design into the PC control terminal, The command is sent to the PLC by the control terminal through the upper computer software; then the motion controller controls the servo motor Ⅰ5, servo motor Ⅱ7, servo motor Ⅲ9, servo motor Ⅴ36 to use the motor cage 23 to drive the synchronous belt module guide rail Ⅰ1, the synchronous belt module guide rail Ⅳ10 connected to the synchronous belt module 1 using the transmission shaft Ⅰ8, the synchronous belt guide rail Ⅱ3 installed on the slider 2, and the synchronous belt guide rail Ⅲ6. The servo motor Ⅳ32 drives the printing plane to move along the direction of the ball screw 18 through the transmission shaft Ⅱ19, the pulley 17 and the pulley 31, so as to realize the three-dimensional spatial movement of the nozzle 4;

[0050] The air source is added to the dispensing pressure tank A and the dispensing pressure tank B to maintain the pressure of glue A and glue B. When the valves of glue A and glue B are opened and the valve of the cleaning tank is closed, the gear pump is used to pump glue A and glue B into the dynamic mixing tube, and the DC motor drives the auger to rotate to improve the uniformity of the adhesive mixing. The outlet of the dynamic mixing tube is connected to the nozzle 4 to extrude the adhesive.

[0051] While the extrusion motion mechanism drives the nozzle 4 to move, the nozzle 4 extrude materials. While the powder bin 13 moves along the synchronous belt module guide rail V12 and the synchronous belt module VI14 connected by the connecting plate 11, powder is manually added to the powder bin 13. The powder flows out from the gap of the hopper 37 installed in the powder bin 13 to the printing plane 29. The powder is flattened under the action of the scraper 35, thereby achieving material stacking in the process of continuous movement and spraying; then after a long period of printing, the part printing is completed. The electromagnet 30 is powered off, the positioning pin 16 is removed, the lock 20 is opened, the powder bed mechanism is removed, and the printed part is removed for post-processing.

[0052] Close the A glue and B glue valves, open the cleaning tank valve, and spray the cleaning agent along the pipeline to achieve the effect of cleaning the pipeline and the dynamic mixing tube. Turn on the DC motor during cleaning to improve the cleaning effect.

[0053] The above-described embodiments merely express the implementation methods of the present invention, but they should not be understood as limiting the scope of the present invention. It should be pointed out that for those skilled in the art, several modifications and improvements can be made without departing from the concept of the present invention, which all belong to the protection scope of the present invention.

Claims

1. A nozzle embedded 3D printing device for thermosetting wood-plastic composite materials, characterized in that: The embedded nozzle 3D printing device includes a frame and an extrusion motion mechanism, a powder spreading mechanism, a powder bed mechanism, a printing platform motion mechanism and a feeding system provided on the frame, and the extrusion motion mechanism is fed with materials through the feeding system; the details are as follows: The extrusion motion mechanism comprises a synchronous belt module guide rail I (1), a synchronous belt module guide rail II (3), a synchronous belt module guide rail III (6), a synchronous belt module guide rail IV (10), a nozzle (4), a servo motor I (5), a servo motor II (7), and a servo motor III (9); specifically, the synchronous belt module guide rail I (1) and the synchronous belt module guide rail IV are parallelly mounted on the left and right sides of the top of the frame, the sliders on the two synchronous belt module guide rails I (1) are directed upward, connected by a transmission shaft I (8), and connected by a servo motor III (9). Provide power; install the synchronous belt module guide rail II (3) on the two sliders of the synchronous belt module guide rail I (1), the slider of the synchronous belt module guide rail II (3) is facing forward, and the power is provided by the servo motor II (7); vertically install the synchronous belt module guide rail III (6) on the slider of the synchronous belt module guide rail II (3), and the power is provided by the servo motor I (5); the nozzle (4) is connected to the feeding system and installed above the slider of the synchronous belt module guide rail III (6), so that it cooperates with the movement of the printing platform (29) to realize the printing process according to the specified path; The powder spreading mechanism comprises a connecting plate (11), a synchronous belt module V (12), a powder bin (13), a hopper (37), a synchronous belt module VI (14), a scraper (35) and a servo motor V (36); the synchronous belt module guide rails V (12) and VI (14) are horizontally installed on the rear side of the frame, and the two are connected through the connecting plate (11); the servo motor V (36) is installed on the rear side of the connecting plate (11) to provide power for the movement of the sliders of the synchronous belt module guide rails V (12) and VI (14); the powder bin (13) is installed on the connecting plate (11), and the hopper (37) and the scraper (35) are stacked thereon; The powder bed mechanism comprises a printing platform (29), the bottom surface of the powder bed mechanism is a movable printing platform (29), and a roller is installed at the bottom of the powder bed mechanism to push it into a working position; The printing platform movement mechanism comprises a servo motor IV (32), a ball screw (18), a transmission shaft II (19), a lifting platform (34), an electromagnet (30), and an electromagnet mounting platform (28), and is used to control the movement of the printing platform (29); an electromagnet (30) is mounted at the bottom of the powder bed mechanism, and when the electromagnet (30) and the electromagnet mounted on the printing platform (29) are energized, adsorption is completed, and then the powder bed mechanism is fixed.

2. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: In the printing platform motion mechanism, the servo motor IV (32) provides power to the ball screw (18) through the pulley (17), thereby driving the printing platform (29) to move vertically on the ball screw (18), and realizing layer-by-layer stacking and forming of the printed model through the lifting platform (34); the four ball screws (18) shown are vertically installed on four aluminum profiles, and the lifting platform (34) is horizontally installed on the top, and four electromagnets (30) are installed around the lifting platform (34). When the electromagnets are energized, the printing platform (29) is fixed on the lifting platform (34).

3. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: The feeding system includes a dispensing pressure barrel A, a dispensing pressure barrel B, a cleaning tank, a gear pump A, a gear pump B, a three-way ball valve, a DC motor and a dynamic mixing tube, and a pipeline with controllable flow direction is connected through the three-way ball valve; specifically: The gas source outlet is connected to the gas inlets of the dispensing pressure tanks A and B through pipelines to maintain the pressure of the A glue in the dispensing pressure tank A and the B glue in the dispensing pressure tank B; the gas source outlet is connected to the gas inlet of the cleaning tank through a pipeline to squeeze out the cleaning agent; the liquid outlet of the dispensing pressure tank A is connected to the inlet of the gear pump A, and the liquid outlet of the dispensing pressure tank B is connected to the inlet of the gear pump B. The amount and ratio of the A glue and the B glue are accurately controlled by controlling the gear pump with a servo motor; the outlets of the gear pump A and the gear pump B are respectively connected to the first valve ports of the two three-way ball valves, the second valve ports of the two three-way ball valves are connected to the diverter, and the third valve ports of the two three-way ball valves are connected to the dynamic mixing tube; The liquid outlet of the cleaning tank is connected to a tee, and the other two outlets of the tee are connected to the diverter; A DC motor is installed on the top of the flow divider; the inlet of the dynamic mixing tube is installed at the lower end of the flow divider, and is used to fully mix glue A and glue B into a binder; the outlet of the dynamic mixing tube is connected to the inlet of the nozzle (4), and is used to transport the binder to the nozzle (4), and the nozzle (4) extrude the binder to achieve printing.

4. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 3, characterized in that: When the A-glue and B-glue valves are opened and the cleaning tank valve is closed, the A-glue and B-glue enter the dynamic mixing tube, the outlet of the dynamic mixing tube is connected to the nozzle (4), and the DC motor drives the auger to rotate to improve the uniformity of adhesive mixing; when the A-glue and B-glue valves are closed and the cleaning tank valve is opened, the cleaning agent is sprayed out along the pipeline to achieve the effect of cleaning the pipeline and the dynamic mixing tube; the DC motor is turned on during cleaning.

5. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: In the extrusion motion mechanism, the servo motor III (9) cooperates with the motor cage (23) to be installed above the synchronous belt module guide rail I (1), the servo motor II (7) cooperates with the motor cage (23) to be installed on the right side of the synchronous belt module guide rail II (3), and the servo motor I (5) is installed at the top of the synchronous belt module guide rail III (6) to provide power for the slider.

6. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: In the extrusion motion mechanism, the sliders (2) of the two synchronous belt module guide rails Ⅰ (1) are both equipped with brackets (22) for installing the synchronous belt module guide rails Ⅱ (3).

7. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: The outer wall of the powder bed mechanism is composed of four aluminum plates (24): two adjacent aluminum plates (24) in the outer wall of the powder bed mechanism are fixed by inner angle aluminum (25) and outer angle aluminum (15); multiple pulleys (21) are installed on the aluminum profiles on both sides of the powder bed mechanism; a lock (20) is installed between the gap between the aluminum plate (24) on the front side of the powder bed mechanism and the aluminum profile to fix the powder bed mechanism, and the positioning pin frame 27 on the rear side of the powder bed mechanism and the powder bed positioning frame (28) are connected using positioning pins (26) to complete the positioning of the powder bed mechanism.

8. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: A felt is installed between the printing platform (29) and the outer wall of the powder bed mechanism.

9. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: In the powder spreading mechanism, a scraper (35) is installed below the hopper (37) to scrape the powder filled on the printing plane. During the movement of the powder bin (13), a layer of powder is spread on the printing platform (29) and is flattened by the scraper (35).

10. The nozzle embedded 3D printing device for thermosetting wood-plastic composite materials according to claim 1, characterized in that: In the printing platform movement mechanism, the tightness of the conveyor belt is adjusted by a tensioning wheel (33).

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