3D Printing Assisted Extrusion Method and Device for Carbon Fiber Reinforced Plastic Filament

Abstract

The present invention discloses a 3D printing assisted extrusion method and a printing device for carbon fiber reinforced plastic filaments, relating to the technical field of 3D printing. The assisted extrusion method includes the following steps: S110, a compensation channel communicating with the feeding channel is arranged on one side of the feeding channel, and a pressure compensation device is arranged in the compensation channel; S120, start the 3D printer and the pressure compensation device, so that the carbon fiber reinforced plastic enters the hot melting mechanism of the 3D printer, and the carbon fiber reinforced plastic is melted into filaments in the hot melting mechanism; S130, the driving and driven wheels of the 3D printer push the filaments to sink towards the nozzle; S140, the pressure compensation device provides pressure compensation for the filaments in the feeding channel according to the state of the driving and driven wheels. When the main extrusion pressure of the 3D printer is insufficient, the pressure compensation device can compensate the extrusion pressure for the filaments, so that the filaments can continue to be extruded tightly and continuously from the nozzle, thereby effectively solving the problems of smooth wire feeding and easy wire breakage during printing.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing, and in particular to a 3D printing assisted extrusion method and a printing device for carbon fiber reinforced plastic filaments. Background Art

[0002] In related technologies, when an FDM type 3D printer uses carbon fiber reinforced plastic to print works, the following problems often occur:

[0003] (1) After the printer is used for a long time, the driven wheel will wear, causing the gap between the main and driven wheels to expand, resulting in wire feeding slippage or the wire swaying between the wheels, leading to insufficient extrusion pressure supply, unstable feeding amount at the nozzle, reducing the surface accuracy of the printed model, and even causing wire breakage in severe cases.

[0004] (2) The heating temperature of the hot melting mechanism affects the viscosity of the wire during the extrusion process. If the temperature is too low, the extrusion speed will slow down, resulting in an increase in the extrusion pressure at the nozzle and even nozzle blockage; if the temperature is too high, the wire is too soft, which is not conducive to extrusion, and even causes the wire to carbonize, still easily causing nozzle blockage.

[0005] (3) It is difficult to debug various parameters of the printer. When the work printing is completed, due to the influence of the inertial force and gravity of the moving wheel, the wire is extruded excessively, resulting in wire drawing.

[0006] (4) Using carbon fiber reinforced plastic for 3D printing often causes nozzle blockage. Even for nozzles suitable for a standard of 0.4 mm or larger, short-cut carbon fiber filaments or particles are still likely to cause nozzle blockage. And due to the discontinuity of carbon fibers, it is easy to cause uneven extrusion, resulting in wire breakage or wire drawing problems. Summary of the Invention

[0007] The present invention aims to at least solve one of the technical problems existing in the prior art. For this purpose, the present invention provides a 3D printing assisted extrusion method for carbon fiber reinforced plastic filaments, which can effectively solve the problems of uneven wire feeding and extrusion and easy wire breakage during the fused deposition 3D printing of carbon fiber reinforced plastic.

[0008] The present invention also provides a printing device.

[0009] An embodiment of a method for assisting the extrusion of carbon fiber reinforced plastic filaments in 3D printing according to an aspect of the present invention includes the following steps: S110, a compensation channel communicating with the feeding channel is arranged on one side of the feeding channel, and a pressure compensation device is arranged in the compensation channel; S120, start the 3D printer and the pressure compensation device, so that the carbon fiber reinforced plastic enters the melting mechanism of the 3D printer, and the carbon fiber reinforced plastic is melted into filaments in the melting mechanism; S130, the driving and driven wheels of the 3D printer push the filaments downward toward the nozzle; S140, the pressure compensation device provides pressure compensation for the filaments in the feeding channel according to the state of the driving and driven wheels; wherein, the extrusion force of the driving and driven wheels on the filaments is F1, the extrusion force of the filaments on the pressure compensation device is F2, and the extrusion force of the pressure compensation device on the filaments is F3.

[0010] Further, in step S140, the states of the driving and driven wheels include the driving and driven wheels slipping, the rotational speed of the driving and driven wheels slowing down or the driving and driven wheels stopping rotating.

[0011] Further, in step S140, when the driving and driven wheels slip, F3 > F2.

[0012] Further, in step S140, when the driving and driven wheels resume normal rotation, F3 = F2.

[0013] Further, the compensation channel is in a closed state. In step S140, when the rotational speed of the driving and driven wheels slows down or stops rotating, the pressure compensation device creates a negative pressure environment in the compensation channel.

[0014] Further, the pressure compensation device includes a permanent magnet, a spring, an electromagnet and a sealing ring arranged in the compensation channel. The permanent magnet is located between the feeding channel and the electromagnet, the spring is located between the permanent magnet and the electromagnet, the sealing ring is sleeved on the outer periphery of the permanent magnet, and the sealing ring is slidably connected with the compensation channel. The magnitude and direction of the acting force of the permanent magnet on the filaments are controlled by changing the current of the electromagnet.

[0015] Further, the compensation channel is smaller than the feeding channel to prevent the permanent magnet from entering the feeding channel.

[0016] A printing device according to another embodiment of the present invention includes: a printing assembly, including a hot melting mechanism, an extrusion mechanism, and a nozzle. The hot melting mechanism is communicated with the nozzle through a feeding channel. The extrusion mechanism is configured to push the wire material in the feeding channel towards the nozzle; a pressure compensation device is disposed in a compensation channel communicated with the feeding channel. The pressure compensation device includes an extrusion member and a driving member. The extrusion member is movably installed in the compensation channel. The driving member is configured to drive the extrusion member to move in the compensation channel to change the extrusion force of the driving member on the wire material in the feeding channel.

[0017] Further, the extrusion member includes a permanent magnet, the driving member includes an electromagnet, and the pressure compensation device further includes a spring. The spring is disposed between the permanent magnet and the electromagnet.

[0018] Further, the pressure compensation device includes a sealing ring. The sealing ring is sleeved on the outer periphery of the permanent magnet. The sealing ring is slidably connected to the compensation channel.

[0019] The foregoing 3D printing auxiliary extrusion method for carbon fiber reinforced plastic wire materials has at least the following beneficial effects: By arranging a pressure compensation device in the compensation channel on one side of the feeding channel, when the main extrusion force of the 3D printer is insufficient, the pressure compensation device can compensate the extrusion force for the wire material, so that the wire material can continue to be extruded tightly and continuously from the nozzle, thereby effectively solving the problems of unsmooth wire feeding and easy wire breakage during the fused deposition 3D printing of carbon fiber reinforced plastics, and facilitating the improvement of the current situation of easy blockage of the nozzle wire material. In addition, when the 3D printing device stops printing, the pressure compensation device can create a negative pressure environment in the compensation channel, and can suck back the excessive wire material extruded from the nozzle, thereby effectively avoiding the situation of wire drawing.

[0020] The additional aspects and advantages of the present invention will be given in part in the following description, will become apparent in part from the following description, or will be understood through the practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The following further describes the present invention with reference to the drawings and embodiments, wherein:

[0022] Figure 1 is a schematic structural diagram of the printing device according to an embodiment of the present invention;

[0023] Figure 2 is a right view schematic diagram of the printing device according to an embodiment of the present invention;

[0024] Figure 3 is Figure 2 a cross-sectional view taken along line A-A in

[0025] Figure 4 is Figure 1Top view schematic diagram;

[0026] Figure 5 is Figure 4 Cross-sectional schematic diagram of B-B in

[0027] Reference numerals:

[0028] 110, feeding channel; 120, compensation channel; 130, nozzle;

[0029] 200, pressure compensation device; 210, permanent magnet; 220, electromagnet; 230, spring; 240, sealing ring; 250, end cover. Detailed implementation manners

[0030] Embodiments of the present invention will be described in detail below. Examples of the embodiments are shown in the drawings, where the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below by referring to the drawings are exemplary and are only used to explain the present invention, and should not be construed as a limitation of the present invention.

[0031] In the description of the present invention, it should be understood that for the orientation description, such as up, down, front, back, left, right, etc., the orientation or positional relationship indicated is based on the orientation or positional relationship shown in the drawings. It is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the present invention.

[0032] In the description of the present invention, the meaning of several is more than one, the meaning of multiple is more than two, greater than, less than, exceeding, etc. are understood as not including the present number, and above, below, within, etc. are understood as including the present number. If there is a description of first and second, it is only for the purpose of distinguishing technical features and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence relationship of the indicated technical features.

[0033] In the description of the present invention, unless otherwise clearly defined, words such as setting, installing, connecting, etc. should be understood in a broad sense. Those skilled in the art can reasonably determine the specific meanings of the above words in the present invention in combination with the specific content of the technical solution.

[0034] In the description of the present invention, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic expressions of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0035] An auxiliary extrusion method for 3D printing of carbon fiber reinforced plastic filaments according to an embodiment of one aspect of the present invention includes the following steps:

[0036] S110, a compensation channel 120 communicating with the feeding channel 110 is arranged on one side of the feeding channel 110, and a pressure compensation device 200 is arranged in the compensation channel 120;

[0037] S120, start the 3D printer and the pressure compensation device 200, so that the carbon fiber reinforced plastic enters the hot melting mechanism of the 3D printer, and the carbon fiber reinforced plastic melts into filaments in the hot melting mechanism;

[0038] S130, the driving and driven wheels of the 3D printer push the filaments to sink towards the nozzle 130;

[0039] S140, the pressure compensation device 200 provides pressure compensation for the filaments in the feeding channel 110 according to the state of the driving and driven wheels.

[0040] Among them, the extrusion force of the driving and driven wheels on the filaments is F1, the extrusion force of the filaments on the pressure compensation device is F2, and the extrusion force of the pressure compensation device 200 on the filaments is F3.

[0041] For the aforementioned auxiliary extrusion method for 3D printing of carbon fiber reinforced plastic filaments, by arranging the pressure compensation device 200 in the compensation channel 120 on one side of the feeding channel 110, when the main extrusion force provided by the 3D printer is insufficient, the pressure compensation device 200 can compensate the extrusion force for the filaments, so that the filaments can continue to be extruded tightly and continuously from the nozzle 130, thereby effectively solving the problems of smooth wire feeding and easy wire breakage during the fused deposition 3D printing of carbon fiber reinforced plastics, and facilitating the improvement of the current situation of easy blockage of the wire material at the nozzle 130. In addition, when the 3D printing device stops printing, the pressure compensation device 200 can create a negative pressure environment in the compensation channel 120, and can suck back the excessive filaments extruded from the nozzle 130, thereby effectively avoiding the situation of wire drawing.

[0042] In the aforementioned embodiment, the pressure compensation device 200 includes a permanent magnet 210, a spring 230, an electromagnet 220, a sealing ring 240, and an end cap 250, which are disposed in the compensation channel 120. The permanent magnet 210 is located between the feed channel 110 and the electromagnet 220, the spring 230 is located between the permanent magnet 210 and the electromagnet 220, and the sealing ring 240 is sleeved around the outer periphery of the permanent magnet 210. The sealing ring 240 is slidably connected to the compensation channel 120. The magnitude and direction of the force exerted by the permanent magnet 210 on the wire is controlled by varying the current in the electromagnet 220. The end cap 250 is provided with a control device for controlling the movement of the permanent magnet 210 to achieve pressure compensation.

[0043] Furthermore, the compensation channel 120 is smaller than the feeding channel 110 to prevent the permanent magnet 210 from entering the feeding channel 110 .

[0044] In step S140 , the states of the driving and driven wheels include the driving and driven wheels slipping, the rotation speed of the driving and driven wheels slowing down, or the driving and driven wheels stopping rotating.

[0045] In step S140, when the master and slave wheels slip, F3 > F2. In practice, slippage can lead to insufficient primary extrusion force F1, resulting in a reduction in both F1 and F2. At this point, F3 is greater than F2, and permanent magnet 210 pushes the filament, allowing the filament in feed channel 110 to remain tightly continuous and smoothly extruded from nozzle 130. This improves printing stability and prevents problems such as filament breakage or nozzle blockage caused by uneven filament extrusion.

[0046] In step S140, when the master and slave wheels resume normal rotation, F3 = F2. As the wire material accumulates within the feed channel 110, the extrusion force F2 exerted by the wire material on the pressure compensation device 200 gradually increases. The force F2 acts on the permanent magnet 210, moving it toward the electromagnet 220. The repulsive force F3 exerted on the permanent magnet 210 by the electromagnet 220 also increases, until F2 equals F3, achieving equilibrium between the two forces. At this point, the wire material is extruded normally.

[0047] It should be noted that compensation channel 120 is sealed. In step S140, when the speed of the master and slave wheels slows or stops, pressure compensation device 200 creates an underpressure environment within compensation channel 120. Specifically, pressure compensation device 200 reverses the current flowing through electromagnet 220, causing electromagnet 220 and permanent magnet 210 to attract each other. At this point, F3 reverses, and permanent magnet 210 momentarily approaches electromagnet 220, creating an underpressure environment within compensation channel 120. This draws the remaining wire material from nozzle 130 back into the nozzle, effectively preventing wire drawing.

[0048] See also Figures 1 to 5As shown in the figure, another embodiment of the present invention discloses a printing device, which includes a printing component and a pressure compensation device 200.

[0049] As Figures 1 to 3 shown in the figure, the printing component includes a hot melting mechanism, an extrusion mechanism, and a nozzle 130. The hot melting mechanism is communicated with the nozzle 130 through a feeding channel 110. The extrusion mechanism is used to push the wire material in the feeding channel 110 towards the nozzle 130. Specifically, the hot melting mechanism can melt the carbon fiber reinforced plastic fed into the hot melting mechanism into a wire material. Then, under the extrusion of the extrusion mechanism, the wire material is extruded through the feeding channel 110 to the nozzle 130 to complete the printing work. In this embodiment, the carbon fiber reinforced plastic enters the hot melting mechanism under the action of a driving wheel; the extrusion mechanism includes a driving wheel and a driven wheel. The driving wheel and the driven wheel push the wire material downward to make the wire material sink towards the nozzle 130. Among them, the aperture of the feeding channel 110 is quite different from the aperture of the nozzle 130. Therefore, the wire material will deposit after reaching the interface between the feeding channel 110 and the nozzle 130. It should be noted that the extrusion force of the driving wheel and the driven wheel on the wire material is F1.

[0050] As Figures 1 to 3 shown in the figure, the pressure compensation device 200 is arranged in a compensation channel 120 communicated with the feeding channel 110. The pressure compensation device 200 includes an extrusion part and a driving part. The extrusion part is movably installed in the compensation channel 120. The driving part is used to drive the extrusion part to move in the compensation channel 120 to change the extrusion force of the driving part on the wire material in the feeding channel 110.

[0051] Specifically, please refer to Figure 4 and Figure 5 shown in the figure. After the wire material deposited at the interface between the feeding channel 110 and the nozzle 130 accumulates to a certain amount, it will gradually flow into the compensation channel 120. At this time, the wire material acts on the extrusion part with an extrusion force F2, and the extrusion force of the extrusion part on the wire material is F3. When the wire material can be normally extruded from the nozzle 130, the extrusion force F2 of the wire material on the extrusion part is equal to the extrusion force F3 of the extrusion part on the wire material.

[0052] When the driving wheel and the driven wheel slip, the extrusion force F1 of the driving wheel and the driven wheel on the wire material will decrease. If the pressure of the wire material is not compensated, it will cause the wire material to be fed and extruded smoothly or even broken. In this application, when the extrusion force F1 of the driving wheel and the driven wheel on the wire material decreases due to slipping or other reasons, the acting force F2 of the wire material on the extrusion part will also decrease. At this time, the acting force F3 of the extrusion part on the wire material is greater than F2. Therefore, the extrusion part can play a role in compensating the pressure of the wire material, effectively ensuring the continuous extrusion of the wire material and avoiding the situation of smooth wire feeding or even wire breakage.

[0053] When the 3D printer stops, the rotational speeds of the driving and driven wheels gradually decrease until the driving and driven wheels stop. At this time, the driving member drives the extrusion member to move in the reverse direction, that is, drives the extrusion member to move along the direction away from the feeding channel 110, so that an underpressure environment is instantaneously formed in the compensation channel 120, thereby being able to suck back the excess wire of the pressing head, and thus effectively avoiding the occurrence of wire drawing when the 3D printer stops.

[0054] In some embodiments, as Figure 4 and Figure 5 shown, the extrusion member includes a permanent magnet 210, the driving member includes an electromagnet 220, and the pressure compensation device 200 further includes a spring 230. The spring 230 is disposed between the permanent magnet 210 and the electromagnet 220. Further, the pressure compensation device 200 includes a sealing ring 240. The sealing ring 240 is sleeved on the outer periphery of the permanent magnet 210, and the sealing ring 240 is slidably connected to the compensation channel 120. Among them, the presence or absence of the magnetism of the electromagnet 220 can be controlled by turning on and off the current; the magnitude of the magnetism of the electromagnet 220 can be controlled by adjusting the strength of the current, the magnitude of the resistance, or the number of turns of the coil; the magnetic pole direction of the electromagnet 220 can be controlled by changing the direction of the current.

[0055] It should be understood that the judgment of the magnetic field direction: Hold the energized solenoid with the right hand so that the four fingers are bent in the same direction as the current direction, and the end pointed by the thumb is the N pole of the energized solenoid. The calculation of the magnetic field intensity (solenoid): , the magnetic field intensity decreases as the distance between the magnetic field and the coil increases. By adjusting the magnitude of the magnetic field intensity of the electromagnet 220, an adjustable variable magnetic field repulsive (attractive) force can be applied to the permanent magnet 210, thereby providing an extrusion compensation force for the printer.

[0056] The embodiments of the present invention have been described in detail above with reference to the accompanying drawings. However, the present invention is not limited to the above embodiments, and various changes can be made without departing from the gist of the present invention within the scope of knowledge possessed by those of ordinary skill in the art. In addition, the embodiments of the present invention and the features in the embodiments can be combined with each other without conflict.

Claims

1. A 3D printing assisted extrusion method for carbon fiber reinforced plastic filaments, characterized in that, It includes the following steps: S110. A compensation channel communicating with the feeding channel is arranged on one side of the feeding channel, and a pressure compensation device is arranged in the compensation channel; the pressure compensation device includes a permanent magnet, a spring, an electromagnet and a sealing ring arranged in the compensation channel. The permanent magnet is located between the feeding channel and the electromagnet, the spring is located between the permanent magnet and the electromagnet, the sealing ring is sleeved on the outer periphery of the permanent magnet, and the sealing ring is slidably connected with the compensation channel. The magnitude and direction of the force of the permanent magnet on the wire are controlled by changing the current of the electromagnet; S120. Start the 3D printer and the pressure compensation device, so that the carbon fiber reinforced plastic enters the melting mechanism of the 3D printer, and the carbon fiber reinforced plastic is melted into a wire in the melting mechanism; S130. The driving and driven wheels of the 3D printer push the wire downward toward the nozzle; S140. The pressure compensation device provides pressure compensation for the wire in the feeding channel according to the working state of the driving and driven wheels; the states of the driving and driven wheels include the driving and driven wheels slipping, the rotational speed of the driving and driven wheels slowing down or the driving and driven wheels stopping rotating; when the rotational speed of the driving and driven wheels slows down or stops rotating, the pressure compensation device creates an underpressure environment in the compensation channel; Wherein, the extrusion force of the driving and driven wheels on the wire is F1, the extrusion force of the wire on the pressure compensation device is F2, and the extrusion force of the pressure compensation device on the wire is F3.

2. The 3D printing assisted extrusion method of carbon fiber reinforced plastic filaments according to claim 1, characterized in that, In step S140, when the driving and driven wheels slip, F3 > F2.

3. The 3D printing assisted extrusion method of carbon fiber reinforced plastic filaments according to claim 1, characterized in that, In step S140, when the driving and driven wheels resume normal rotation, F3 = F2.

4. The 3D printing assisted extrusion method of carbon fiber reinforced plastic filaments according to claim 1, characterized in that, The compensation channel is smaller than the feeding channel to prevent the permanent magnet from entering the feeding channel.

Images