Wire feeding structure of 3D printer

Abstract

The invention relates to a 3D printer wire feeding structure which comprises a belt body, a base body, a protruding block, a tearing part and a driving part, the belt body is arranged in the length direction of a consumable wire, the belt body is pasted and fixed to the consumable wire through an adhesive layer, the protruding block is formed by protruding forwards from the front side face of the base body, and the tearing part is arranged on the base body. A protruding block is arranged on the base body, a through hole allowing the consumable wire to penetrate downwards is formed in the protruding block, the tearing part and the driving part are both arranged on the base body, and the driving part is used for driving the tearing part to pull a belt body on the portion, located on the lower side of the through hole, of the consumable wire downwards and tearing the belt body from the consumable wire. Due to the adoption of the technical scheme, when the 3D printing wire feeding structure is used, the consumable wire is almost not abraded, and the possibility of slipping and incapability of conveying the consumable wire can be reduced.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of 3D printing technology, and particularly relates to a 3D printer filament feeding structure. BACKGROUND

[0002] 3D printing, also known as additive manufacturing technology, is a technology for manufacturing a solid part by layer-by-layer material accumulation according to three-dimensional CAD data. The existing 3D printer printing head includes two parts, one part is a filament feeding structure (i.e. an extruder), and the other part is a nozzle connected to the filament feeding structure. The filament feeding structure feeds the consumable filament into the inlet of the nozzle through a feeding wheel. The consumable filament entering the nozzle is melted at high temperature and then discharged from the outlet of the nozzle to perform 3D printing.

[0003] The existing filament feeding structure has two feeding wheels, which clamp the consumable filament in the middle. When the feeding wheels rotate, the consumable filament can be fed under the friction between the feeding wheels and the consumable filament. However, during 3D printing, the feeding wheels are prone to causing wear to the consumable filament, which can lead to slippage or even failure to feed the consumable filament. SUMMARY

[0004] Therefore, the present application aims to provide a 3D printer filament feeding structure to solve the problem that the feeding wheels are prone to causing wear to the consumable filament, which can lead to slippage or even failure to feed the consumable filament.

[0005] The present application is achieved by the following technical solutions: A 3D printer filament feeding structure includes a belt body, a seat body, a protruding block, a tearing part, and a driving part. The belt body is arranged along the length direction of the consumable filament and is fixed to the consumable filament by an adhesive layer. The protruding block protrudes forward from the front side of the seat body. A through hole is formed in the protruding block for the consumable filament to pass downward. The tearing part and the driving part are both arranged on the seat body. The driving part is used to drive the tearing part to pull down the belt body on the part of the consumable filament below the through hole and tear the belt body from the consumable filament.

[0006] Further, the belt body is two, and the two belt bodies are respectively fixed to the two opposite sides of the consumable filament. The tearing part is two, and the driving part is used to synchronously drive the two tearing parts to pull down the part of the corresponding belt body below the through hole and tear the corresponding belt body from the consumable filament.

[0007] Further, the tearing part includes a direction-changing wheel and a belt feeding shaft. The direction-changing wheel and the belt feeding shaft are both connected to the seat body through a rotating shaft. The direction-changing wheel is located obliquely below the through hole, and the belt feeding shaft is located on the side of the direction-changing wheel away from the axis of the through hole. The belt on the part of the consumable wire below the through hole sequentially passes the lower side of the corresponding variable direction wheel and the upper side of the tape feeding shaft; The driving part is used for driving the tape feeding shaft to rotate.

[0008] Further, the driving part comprises a first motor, two driving pulleys, two driven pulleys and two transmission belts, the first motor is fixedly arranged on the seat body, the two driving pulleys are fixedly arranged on the rotating shaft of the first motor, the two driven pulleys are fixedly connected to the tape feeding shaft of the tearing part one by one, one transmission belt is arranged around one driving pulley and one driven pulley, and the other transmission belt is arranged around the other driving pulley and the other driven pulley.

[0009] Further, the tearing part further comprises a supporting rod, a tape feeding wheel and a counterweight, the first end of the supporting rod is fixedly connected to the seat body, the second end of the supporting rod extends out of the range of the 3D printer, and the tape feeding wheel is connected to the second end of the supporting rod through a rotating shaft; The belt on the part of the consumable wire below the through hole sequentially passes the lower side of the corresponding variable direction wheel, the upper side of the corresponding tape feeding shaft and the upper side of the corresponding tape feeding wheel, and then extends downward and is fixedly connected to the counterweight, and the top of the tape feeding shaft is higher than the top of the variable direction wheel and the top of the tape feeding wheel.

[0010] Further, the tearing part further comprises a winding shaft, a winding wheel, a rubber column and a second motor, the winding shaft is connected to the seat body through a rotating shaft, the middle part of the winding wheel is provided with a shaft hole, the shaft hole is sleeved on the winding shaft, the rubber column is arranged on the winding wheel, the rubber column abuts against the outer circumferential surface of the winding shaft, and the second motor is used for driving the winding shaft to rotate; The belt on the part of the consumable wire below the through hole sequentially passes the lower side of the corresponding variable direction wheel, the upper side of the corresponding tape feeding shaft and the upper side of the corresponding tape feeding wheel, and then extends downward and is fixedly connected to the counterweight, and the top of the tape feeding shaft is higher than the top of the variable direction wheel and the top of the tape feeding wheel.

[0011] Further, a screw hole is formed in the winding wheel, the screw hole is arranged along the radial direction of the winding wheel, one end of the screw hole is communicated with the shaft hole, the other end of the screw hole is communicated with the outer circumferential surface of the winding wheel, the rubber column is located in the screw hole, a bolt is screwed in the screw hole, and the screwing end of the bolt holds the rubber column towards the winding shaft.

[0012] Furthermore, the base is also fixed with an upward-facing powder storage box. The bottom wall of the powder storage box has a hole that matches the consumable wire. The hole is directly opposite the through hole. The powder storage box stores powder, and the material of the powder is the same as that of the consumable wire.

[0013] Furthermore, the width of the tape is less than half the circumference of the cross-section of the consumable filament.

[0014] Furthermore, the lower end of the wall of the through hole transitions to the lower side of the protrusion at a rounded corner.

[0015] The beneficial effects of this invention are as follows: When using the 3D printing filament feeding structure described in this invention, there is almost no wear on the filament, which reduces the possibility of slippage and failure to feed the filament.

[0016] Other advantages, objectives, and features of the invention will be set forth in part in the description which follows, and in part will be apparent to those skilled in the art from the following examination, or may be learned from practice of the invention. The objectives and other advantages of the invention can be realized and obtained through the following description. Attached Figure Description

[0017] Figure 1 and Figure 3 This is a schematic diagram of a preferred embodiment of the filament feeding structure of the 3D printer of the present invention; Figure 2 for Figure 1 Enlarged view of 'a' in the middle; Figure 4 for Figure 3 Enlarged view of b in the middle; Figure 5 for Figure 3 Enlarged view of C in the middle; Figure 6 This is a top view of the protrusion in a preferred embodiment of the filament feeding structure of the 3D printer of the present invention; Figure 7 for Figure 6 AA section view; Figure 8 and Figure 10 This is a schematic diagram of another preferred embodiment of the filament feeding structure of the 3D printer of the present invention; Figure 9 for Figure 8 Enlarged view of d in the middle; Figure 11 for Figure 10 Enlarged view of 'e' in the middle; Figure 12 for Figure 10 Enlarged view of f in the middle; Figure 13 A top view of the protrusion in another preferred embodiment of the filament feeding structure of the 3D printer of the present invention; Figure 14 for Figure 13 BB section view; Figure 15 A schematic diagram of the combined structure of the take-up shaft, take-up wheel, rubber column and bolts in another preferred embodiment of the filament feeding structure of the 3D printer of the present invention. Figure 16 A top view of a combined structure of a take-up shaft, a take-up wheel, a rubber column, and bolts in another preferred embodiment of the filament feeding structure of the 3D printer of the present invention. Figure 17 for Figure 16 CC section view.

[0018] In the diagram: Belt body-1; base body-2; protrusion-3; consumable wire-4; through hole-5; nozzle-6; reversing wheel-7; feed shaft-8; first motor-9; driving pulley-10; driven pulley-11; transmission belt-12; support rod-13; feed pulley-14; counterweight-15; ring-16; take-up shaft-17; take-up wheel-18; rubber column-19; second motor-20; bolt-21; powder storage box-22. Detailed Implementation

[0019] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0020] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0021] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0022] In the foregoing description of the present application, it should be noted that the terms "one side", "the other side" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, or the orientation or positional relationship in which the product of the present application is usually placed, and are merely for the convenience of describing the present application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first", "second" and the like are only used to distinguish the description and cannot be understood as indicating or implying relative importance.

[0023] In addition, the term "same" and the like do not mean that the components must be absolutely the same, but there can be slight differences. The term "vertical" only means that the positional relationship between the components is more vertical than "parallel", and does not mean that the structure must be completely vertical, but can be slightly inclined.

[0024] Embodiment one Please refer to Figures 1-7 The present application provides a technical solution: a 3D printer filament feeding structure, comprising a belt body 1, a seat body 2, a protruding block 3, a tearing part and a driving part, the belt body 1 is arranged along the length direction of the consumable filament 4, the belt body 1 is fixed on the consumable filament 4 by an adhesive layer (not shown in the figure), the protruding block 3 protrudes forward from the front side of the seat body 2, a through hole 5 is formed on the protruding block 3 for the consumable filament 4 to pass downward, the tearing part and the driving part are both arranged on the seat body 2, the driving part is used to drive the tearing part to pull down the belt body 1 on the part of the consumable filament 4 below the through hole 5, and tear the belt body 1 from the consumable filament 4.

[0025] When using the 3D printing filament feeding structure of the present application, the nozzle 6 of the 3D printer is installed on the seat body 2, and the inlet of the nozzle 6 is opposite to the through hole 5.

[0026] The end of the consumable filament 4 is passed downward through the through hole 5, the belt body 1 on the part of the consumable filament 4 below the through hole 5 is torn from the consumable filament 4, and the lower end of the consumable filament 4 is inserted into the inlet of the nozzle 6. Then the driving part drives the tearing part to pull down the belt body 1 on the part of the consumable filament 4 below the through hole 5, and tears the belt body 1 from the consumable filament 4, the belt body 1 can pull down the consumable filament 4 under the action of the adhesion force, so as to achieve the purpose of conveying the consumable filament 4. When using the 3D printing filament feeding structure of the present application, almost no wear will be caused to the consumable filament 4, and the possibility of occurrence of the situation that the consumable filament 4 cannot be conveyed can be reduced.

[0027] In the embodiment, the two bands 1 are respectively fixedly attached to the two opposite sides of the consumable wire 4; the two tearing parts are driven by the driving part to synchronously pull down the part of the corresponding band 1 located below the through hole 5 and tear the corresponding band 1 from the consumable wire 4.

[0028] Since the two bands 1 are respectively fixedly attached to the two opposite sides of the consumable wire 4, the two tearing parts can synchronously pull down the part of the corresponding band 1 located below the through hole 5 and tear the corresponding band 1 from the consumable wire 4, so that the forces on the two opposite sides of the consumable wire 4 are balanced, the consumable wire 4 is less likely to deviate laterally, and the consumable wire 4 is less likely to press the band 1 on the hole wall of the through hole 5 laterally, thereby reducing the resistance when the consumable wire 4 is pulled down.

[0029] In the embodiment, the tearing part includes a direction-changing wheel 7 and a belt feeding shaft 8, both of which are connected to the seat body 2 through a rotating shaft, the direction-changing wheel 7 is located obliquely below the through hole 5, and the belt feeding shaft 8 is located on the side of the direction-changing wheel 7 away from the axis of the through hole 5. The band 1 on the part of the consumable wire 4 located below the through hole 5 sequentially passes the lower side of the corresponding direction-changing wheel 7 and the upper side of the belt feeding shaft 8. The driving part is used to drive the belt feeding shaft 8 to rotate.

[0030] When the 3D printing wire feeding structure is used, the end of the consumable wire 4 is passed through the through hole 5 downward. Then the band 1 on the part of the consumable wire 4 located below the through hole 5 is torn from the consumable wire 4, so that the torn band 1 sequentially passes the lower side of the corresponding direction-changing wheel 7 and the upper side of the belt feeding shaft 8, and the band 1 is attached to the upper side of the belt feeding shaft 8.

[0031] Then the driving part drives the belt feeding shaft 8 to rotate. During the rotation of the belt feeding shaft 8, the belt feeding shaft 8 can pull the band 1 under the adhesion force between the band 1 and the belt feeding shaft 8. During the pulling of the band 1 by the belt feeding shaft 8, the part of the consumable wire 4 located below the through hole 5 is pulled down under the direction-changing effect of the direction-changing wheel 7, and the band 1 is torn from the consumable wire 4. In this structure, the driving part can drive the tearing part to pull down the part of the consumable wire 4 located below the through hole 5 and tear the band 1 from the consumable wire 4.

[0032] In the embodiment, the driving part comprises a first motor 9, two driving pulleys 10, two driven pulleys 11 and two transmission belts 12. The first motor 9 is fixedly arranged on the seat body 2. The two driving pulleys 10 are fixedly arranged on the rotating shafts of the first motor 9. The two driven pulleys 11 are fixedly connected to the belt feeding shafts 8 of the two tearing parts respectively. One transmission belt 12 is arranged around one driving pulley 10 and one driven pulley 11. The other transmission belt 12 is arranged around the other driving pulley 10 and the other driven pulley 11.

[0033] The first motor 9 is started to drive the two driving pulleys 10 to rotate. The driving pulleys 10 drive the corresponding driven pulleys 11 to rotate through the corresponding transmission belts 12. The driven pulleys 11 drive the corresponding belt feeding shafts 8 to rotate. The driving part can drive the belt feeding shafts 8 to rotate synchronously. In this way, the driving part can synchronously drive the two tearing parts to pull down the parts of the belt bodies 1 located below the through holes 5 and tear the corresponding belt bodies 1 from the consumable filaments 4.

[0034] In the embodiment, the tearing part further comprises a supporting rod 13, a belt feeding pulley 14 and a counterweight 15. The first end of the supporting rod 13 is fixedly connected to the seat body 2. The second end of the supporting rod 13 extends out of the range of the 3D printer. The belt feeding pulley 14 is connected to the second end of the supporting rod 13 through a rotating shaft. The belt body 1 on the part of the consumable filament 4 located below the through hole 5 extends downward after passing around the lower side of the corresponding deflection wheel 7, the upper side of the corresponding belt feeding shaft 8 and the upper side of the corresponding belt feeding pulley 14 in sequence and is fixedly connected to the counterweight 15. The top of the belt feeding shaft 8 is higher than the top of the deflection wheel 7 and the top of the belt feeding pulley 14.

[0035] When the 3D printing filament feeding structure is used, the end of the consumable filament 4 is inserted into the through hole 5. Then, the belt body 1 on the part of the consumable filament 4 located below the through hole 5 is torn from the consumable filament 4. The torn belt body 1 extends downward after passing around the lower side of the corresponding deflection wheel 7, the upper side of the corresponding belt feeding shaft 8 and the upper side of the belt feeding pulley 14 and is fixedly connected to the counterweight 15. At this time, the part of the belt body 1 corresponding to the upper side of the belt feeding shaft 8 is attached to the upper side of the belt feeding shaft 8. The part of the belt body 1 corresponding to the upper side of the belt feeding pulley 14 is attached to the belt feeding pulley 14.

[0036] During the process that the belt feeding shaft 8 pulls the belt body 1, the part of the belt body 1 located on the side of the belt feeding pulley 14 away from the belt feeding shaft 8 can gradually move downward under the action of the gravity of the counterweight 15. The belt feeding pulley 14 rotates.

[0037] The weight of the counterweight 15 satisfies the following conditions: the weight of the counterweight is sufficient to keep the portion of the belt 1 located on the side of the feed roller 14 away from the feed shaft 8 and below the axis of the feed roller 14 separated from the outer circumferential surface of the feed roller 14; the weight is also sufficient to tear off the excess portion of the belt 1 that is attached to the feed shaft 8, that is, to prevent the portion of the belt 1 that is attached to the feed shaft 8 from increasing, so that the belt 1 will not be wound up on the feed shaft 8; and the weight is insufficient to pull the belt 1 independently, that is, when the feed shaft 8 is not rotating, the weight is insufficient to pull the belt 1.

[0038] With this configuration, the belt 1 will not be wound up on the feeding shaft 8. During the process of the first motor 9 driving the feeding shaft 8 to rotate at a constant speed, the belt 1 will not be pulled at a higher speed due to being wound up on the feeding shaft 8. This will achieve the effect of pulling the belt 1 at a constant speed, thereby achieving the effect of feeding the yarn at a constant speed.

[0039] The support rod 13 supports the counterweight 15 to the outside of the 3D printer, ensuring that the counterweight 15 will not hit the printed part during its downward movement and will not damage the printed part. It also transports the belt 1 to the ground outside the 3D printer. When the counterweight 15 is almost supported on the ground, it is moved upward a certain distance and re-secured to the upper part of the belt 1 located on the side of the feed roller 14 opposite to the feed shaft 8.

[0040] In this embodiment, a ring 16 is fixed on the counterweight 15. The belt 1 is passed through the ring 16, and then the portions of the belt 1 located on both sides of the ring 16 are tied together, which can fix the counterweight 15 to the belt 1, making it relatively convenient to fix the belt 1 and the counterweight 15.

[0041] In this embodiment, a powder storage box 22 with an upward-facing opening is also fixed on the base 2. A hole that matches the consumable wire 4 is formed on the bottom wall of the powder storage box 22. The hole is directly opposite the through hole 5. Powder is stored in the powder storage box 22. The material of the powder is the same as that of the consumable wire 4.

[0042] After the tape 1 is torn from the consumable filament 4, a small amount of adhesive may remain on the consumable filament 4. As the consumable filament 4 moves downward and enters the inlet of the printhead 6, it passes through the powder storage box 22. The powder in the powder storage box 22 can adhere to the surface of the remaining adhesive, causing the surface of the remaining adhesive to lose its adhesiveness. As the consumable filament 4 enters the inlet of the printhead 6, the adhesive remaining on the surface of the consumable filament 4 is less likely to adhere to the side wall of the inlet of the printhead 6, which can reduce the resistance encountered by the consumable filament 4 when entering the printhead 6.

[0043] Furthermore, the powder adhering to the surface of the residual adhesive is made of the same material as the consumable filament 4, and has little impact on the quality of the printed parts.

[0044] In this embodiment, the width of the tape 1 is less than half the perimeter of the cross-section of the consumable filament 4. This structure reduces the resistance to tearing the tape 1 from the consumable filament 4.

[0045] In this embodiment, the lower end of the wall of the through hole 5 and the lower side surface of the protrusion 3 form a rounded transition. This structure makes the transition between the lower end of the wall of the through hole 5 and the lower side surface of the protrusion 3 smooth, which can reduce the resistance encountered when pulling the tape 1 located on the lower side of the through hole 5 downwards.

[0046] Example 2 The difference between this embodiment and Embodiment 1 is that the structure of the tearing part is different, while the rest are the same as in Embodiment 1.

[0047] For details, please refer to Figures 8-17 The tearing part also includes a take-up shaft 17, a take-up wheel 18, a rubber column 19, and a second motor 20. The take-up shaft 17 is connected to the base 2 via a rotating shaft. The take-up wheel 18 has a shaft hole in the middle, and the shaft hole is sleeved on the take-up shaft 17. The rubber column 19 is provided on the take-up wheel 18 and abuts against the outer peripheral surface of the take-up shaft 17. The second motor 20 is used to drive the take-up shaft 17 to rotate. The tape 1 of the consumable filament 4 located on the lower side of the through hole 5 passes through the lower side of the corresponding deflector 7 and the upper side of the corresponding feed shaft 8 in sequence, and is then pasted and fixed to the upper side of the corresponding take-up shaft 18. The top of the feed shaft 8 is higher than the top of the deflector 7 and the top of the take-up shaft 18.

[0048] When using the 3D printing filament feeding structure described in this invention, the end of the filament 4 is passed downward through the through hole 5. Then, the tape 1 on the portion of the filament 4 located below the through hole 5 is torn off the filament 4, so that the torn tape 1 passes sequentially around the lower side of the corresponding deflector 7 and the upper side of the corresponding feed shaft 8, and is then pasted and fixed to the upper side of the take-up wheel 18. At this time, the portion of the tape 1 corresponding to the upper side of the feed shaft 8 is pasted on the upper side of the feed shaft 8.

[0049] Then, the drive unit drives the feed shaft 8 to rotate, while the second motor 20 drives the take-up shaft 17 to rotate, so that the product of the rotational speed of the take-up shaft 17 and the circumference of the cross-section of the take-up wheel 18 is greater than the product of the rotational speed of the feed shaft 8 and the circumference of the cross-section of the feed shaft 8. At this time, the feed shaft 8 can pull the belt 1 at a uniform speed under the action of the adhesive force between the belt 1 and the feed shaft 8. The take-up shaft 17 drives the take-up wheel 18 to rotate through the friction between the take-up shaft 17 and the rubber column 19, so as to wind up the belt 1, so that the belt 1 can be wound on the take-up wheel 18 without scattering.

[0050] The friction between the take-up shaft 17 and the rubber post 19 satisfies the following conditions: during the process of the take-up shaft 17 driving the take-up wheel 18 to rotate through the friction between the take-up shaft 17 and the rubber post 19, the friction is sufficient to cause the take-up wheel 18 to tear off the excess portion of the belt 1 that is stuck to the feed shaft 8, that is, to prevent the portion of the belt 1 that is stuck to the feed shaft 8 from increasing, so that the belt 1 will not be wound up on the feed shaft 8, and the friction is insufficient to cause the take-up wheel 18 to pull the belt 1 independently, that is, when the feed shaft 8 is not rotating, the friction is insufficient to cause the take-up wheel 18 to pull the belt 1.

[0051] This configuration causes slippage between the take-up shaft 17 and the rubber column 19 during rotation, resulting in the average speed at which the take-up wheel 18 takes up the belt 1 being almost equal to the feeding speed of the feed shaft 8. This ensures that the take-up wheel 18 can take up the belt 1 without affecting the uniform pulling speed of the belt 1.

[0052] In this embodiment, a screw hole is formed on the take-up reel 18. The screw hole is arranged radially along the take-up reel 18. One end of the screw hole is connected to the shaft hole, and the other end is connected to the outer peripheral surface of the take-up reel 18. The rubber column 19 is located in the screw hole. A bolt 21 is screwed into the screw hole. The screw-in end of the bolt 21 presses the rubber column 19 towards the take-up shaft 17.

[0053] The bolt 21 can be rotated within the screw hole, moving it toward or away from the take-up shaft 17 to change the compression of the rubber post 19. This allows adjustment of the pressure of the rubber post 19 on the surface of the take-up shaft 17, and consequently, the friction between the rubber post 19 and the take-up shaft 17. The bolt 21 can be rotated multiple times within the screw hole to adjust the friction between the rubber post 19 and the take-up shaft 17 to a suitable level.

[0054] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A filament feeding structure for a 3D printer, characterized in that: The device includes a tape body, a base, a protrusion, a tearing part, and a driving part. The tape body is arranged along the length of the consumable filament and is fixed to the consumable filament by an adhesive layer. The protrusion extends forward from the front side of the base and has a through hole for the consumable filament to pass through downward. The tearing part and the driving part are both provided on the base. The driving part is used to drive the tearing part to pull the tape body on the part of the consumable filament located below the through hole downward and tear the tape body from the consumable filament.

2. The filament feeding structure for a 3D printer according to claim 1, characterized in that: The tape consists of two strips, which are respectively attached and fixed to two opposite sides of the consumable filament; there are two tearing parts, and the driving part is used to synchronously drive the two tearing parts to pull down the corresponding part of the tape located below the through hole, and tear the corresponding tape from the consumable filament.

3. The filament feeding structure for a 3D printer according to claim 2, characterized in that: The tearing part includes a deflector wheel and a feeding shaft. The deflector wheel and the feeding shaft are both connected to the base body via a rotating shaft. The deflector wheel is located obliquely below the through hole, and the feeding shaft is located on the side of the deflector wheel opposite to the axis of the through hole. The tape on the portion of the consumable filament located below the through hole sequentially passes over the lower side of the corresponding reversing wheel and the upper side of the feed shaft. The drive unit is used to drive the belt feed shaft to rotate.

4. The filament feeding structure for a 3D printer according to claim 3, characterized in that: The drive unit includes a first motor, two driving pulleys, two driven pulleys, and two transmission belts. The first motor is fixed on the base. Both driving pulleys are fixed on the shaft of the first motor. The two driven pulleys are fixedly connected to the feed shafts of the two tearing parts in a one-to-one correspondence. One transmission belt is wound around one driving pulley and one driven pulley, and the other transmission belt is wound around another driving pulley and another driven pulley.

5. The filament feeding structure for a 3D printer according to claim 3, characterized in that: The tearing part also includes a support rod, a feed roller and a counterweight. The first end of the support rod is fixedly connected to the base, and the second end extends outside the range of the 3D printer. The feed roller is connected to the second end of the support rod through a rotating shaft. The consumable wire, located on the portion below the through hole, passes sequentially around the lower side of the corresponding deflector, the upper side of the corresponding feed shaft, and the upper side of the corresponding feed wheel before extending downwards and being fixedly connected to the counterweight. The top of the feed shaft is higher than the top of the deflector and the top of the feed wheel.

6. The filament feeding structure for a 3D printer according to claim 3, characterized in that: The tearing part also includes a take-up shaft, a take-up wheel, a rubber column, and a second motor. The take-up shaft is connected to the base body via a rotating shaft. The take-up wheel has a shaft hole in the middle, and the shaft hole is sleeved on the take-up shaft. The rubber column is disposed on the take-up wheel and abuts against the outer circumferential surface of the take-up shaft. The second motor is used to drive the take-up shaft to rotate. The tape on the portion of the consumable filament located below the through hole passes sequentially around the lower side of the corresponding deflector and the upper side of the corresponding feed shaft, and is then pasted and fixed to the upper side of the corresponding take-up shaft. The top of the feed shaft is higher than the top of the deflector and the top of the take-up shaft.

7. The filament feeding structure for a 3D printer according to claim 6, characterized in that: A screw hole is formed on the take-up reel, the screw hole is arranged radially along the take-up reel, one end of the screw hole is connected to the shaft hole, and the other end is connected to the outer peripheral surface of the take-up reel. The rubber column is located in the screw hole, and a bolt is screwed into the screw hole. The screw-in end of the bolt is facing the take-up shaft to press the rubber column.

8. The filament feeding structure for a 3D printer according to claim 1, characterized in that: The base is also fixed with an upward-facing powder storage box. The bottom wall of the powder storage box has a hole that matches the consumable wire. The hole is directly opposite the through hole. The powder storage box stores powder, and the material of the powder is the same as that of the consumable wire.

9. The filament feeding structure for a 3D printer according to claim 1, characterized in that: The width of the strip is less than half the perimeter of the cross-section of the consumable wire.

10. The filament feeding structure for a 3D printer according to claim 1, characterized in that: The lower end of the hole wall of the through hole transitions to the lower side of the protrusion at a rounded corner.

Images