CN212498969U - Material feeding unit and three-dimensional inkjet printer - Google Patents

Abstract

The utility model discloses a material feeding unit and three-dimensional printer, including the fixed plate, be used for carrying out the conveying mechanism of pay-off and be used for with the consumptive material with the hold-down mechanism that conveying mechanism compresses tightly, conveying mechanism and hold-down mechanism fix on the fixed plate, hold-down mechanism is including being used for the pinch roller that compresses tightly consumptive material and conveying mechanism and being used for providing the pinch roller compresses tightly the elastic component of conveying mechanism trend. The utility model discloses a feeding device, its structural design is reasonable, compresses tightly consumptive material and conveying mechanism through the pinch roller for conveying mechanism can last stable transport consumptive material, and the pay-off is reliable, avoids carrying badly, leads to out the silk not smooth.

Description

Material feeding unit and three-dimensional inkjet printer

Technical Field

The utility model relates to a 3D prints technical field, concretely relates to material feeding unit and three-dimensional printer including this material feeding unit suitable for multiple material.

Background

Additive manufacturing is a technology for manufacturing solid parts by a layer-by-layer accumulation method of printing materials, which is called 3D printing technology for short, and is a forming principle for building three-dimensional solid parts based on a discrete-accumulation principle and accumulating the materials layer by layer according to two-dimensional layer data, and is a rapid manufacturing method from bottom to top.

Fdm (fused Deposition modeling) printing materials commonly used in fused Deposition printers are 1.75mm and 3mm diameter wire, the wire material for printing is wound on a feeding wheel, the feeding device feeds the printing wire material into a heating device for heating during printing, the hot melt material (such as ABS, PLA, nylon, wax, etc.) is heated to a critical state, so that the hot melt material is in a semi-fluid state, and is extruded from a wire outlet to form the printing material to form a printing layer. The printing head or the workbench of the FDM fused deposition printer can move up and down in the vertical direction Z, the filament outlet head moves back and forth on the horizontal surface XY plane, printing materials can be quickly overlapped and accumulated layer by layer, each layer is printed into a certain shape according to a track determined by a CAD graph, and a required three-dimensional object model can be printed finally through layer by layer overlapping. The principle of the superposition is that the temperature of the hot melt material is always slightly higher than the solidification temperature, and the temperature of the forming part is slightly lower than the solidification temperature, so that the hot melt material can be fused with the surface of the previous layer immediately after being extruded out of the nozzle. After one layer deposition is finished, the workbench is lowered by one layer thickness distance according to the preset layer thickness, and then melt-blown deposition is continued until the whole solid modeling is finished.

In the multi-color feeding device in the prior art, different materials enter the printing head at the same time, so that congestion and unsmooth filament discharge are often caused. One reason for this is that the feeding devices of the prior art do not allow stable and continuous feeding of a plurality of materials.

Disclosure of Invention

In view of this, in order to overcome the defects of the prior art, the utility model aims at providing an improved feeding device, which can stably convey materials and solve the problem of unsmooth wire discharge caused by material conveying.

In order to achieve the above purpose, the utility model adopts the following technical scheme:

the utility model provides a feeding device, includes the fixed plate, is used for carrying out the conveying mechanism of pay-off and is used for with the consumptive material with the hold-down mechanism that conveying mechanism compresses tightly, conveying mechanism and hold-down mechanism fix on the fixed plate, hold-down mechanism is including being used for the pinch roller that compresses tightly consumptive material and conveying mechanism and being used for providing the pinch roller compresses tightly the elastic component of conveying mechanism trend.

The consumable is pressed with the conveying mechanism through the pressing wheel, so that the conveying mechanism can continuously and stably convey the consumable, the feeding is reliable, the conveying is avoided being poor, and the wire discharging is not smooth.

Preferably, the conveying mechanism comprises a motor and a conveying wheel positioned at the end part of an output shaft of the motor, the pinch roller is used for compressing the consumable materials with the conveying wheel, the consumable materials are compressed with the conveying wheel through the compression effect of the pinch roller, and the consumable materials are continuously and stably conveyed through the conveying wheel.

Preferably, the compressing mechanism further comprises a movable support rotatably arranged on the fixed plate, and the compressing wheels and the elastic pieces are respectively arranged at two end parts of the movable support, so that the compressing wheels on the vertical parts are pushed by the action of the elastic pieces to compress the consumables on the conveying wheels all the time.

More preferably, the movable support comprises a vertical part and a horizontal part, the joint of the vertical part and the horizontal part is rotatably connected to the fixed plate through a rotating shaft, the pressing wheel is installed at the top end of the vertical part, and the elastic part acts on one end of the horizontal part far away from the rotating shaft. The movable support rotates along the rotating shaft, so that the pinch roller on the vertical part is pushed to compress the consumables on the conveying wheel all the time under the action of the elastic piece.

In some embodiments of the utility model, the horizontal part of the movable support is also provided with a hole for the consumable material to pass through, so that the movement of the consumable material can be further limited.

Further preferably, a fixed support is fixed on the fixed plate, a mounting block is mounted on the fixed support corresponding to the elastic element, one end of the elastic element acts on the mounting block, and the other end of the elastic element acts on the movable support. The installation piece is fixed, and the elastic component of fixing on it supports the horizontal part of fixed bolster for pinch roller on the vertical portion of fixed bolster compresses tightly the consumptive material on the delivery wheel all the time.

Preferably, the mounting block is further provided with a limiting part for limiting the elastic part, and the elastic part is sleeved outside the limiting part. The elastic part is preferably a spring, the limiting part is preferably a screw, the spring is sleeved outside the screw, and the screw limits the stretching or compressing movement of the spring.

Preferably, the feeding device comprises a feeding pipe, a joint is installed on the fixed support, and the feeding pipe is connected to the joint.

More preferably, the fixed support is provided with a conveying hole corresponding to the joint, and the consumable enters the feeding pipe through the conveying hole. The fixed bolster has seted up the delivery port promptly, and the delivery port top is installed and is connected with the conveying pipe, and the conveying pipe extends to printer head always. The consumptive material (printing silk) has the storage wheel to emit, gets into between delivery wheel and the pinch roller through the movable support to drive and carry forward by the delivery wheel, get into the conveying pipe through the delivery port, and then move forward and beat printer head.

Preferably, the conveying wheel is a gear; the pinch roller is provided with a limiting groove used for limiting the movement of consumables, and the limiting groove is formed along the circumferential direction of the pinch roller. Set up the spacing groove and make the motion of consumptive material spacing, follow the slot motion all the time, prevent the off tracking, cause and carry badly.

The utility model also provides a three-dimensional printer of including as above material feeding unit.

Compared with the prior art, the utility model discloses an useful part lies in: the utility model discloses a feeding device, its structural design is reasonable, compresses tightly consumptive material and conveying mechanism through the pinch roller for conveying mechanism can last stable transport consumptive material, and the pay-off is reliable, avoids carrying badly, leads to out the silk not smooth.

Drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings needed to be used in the description of the embodiments will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings without creative efforts.

Fig. 1 is a perspective view of a three-dimensional printer according to a preferred embodiment of the present invention;

FIG. 2 is a front view of a three-dimensional printer according to a preferred embodiment of the present invention;

FIG. 3 is a side view of a three-dimensional printer in accordance with a preferred embodiment of the present invention;

fig. 4 is a perspective view of a feeding device in a preferred embodiment of the present invention;

FIG. 5 is a perspective view of a second perspective of a printhead according to a preferred embodiment of the present invention;

FIG. 6 is a perspective view of a third perspective of a preferred embodiment of the printhead;

FIG. 7 is a top view of a preferred embodiment of the printhead of the present invention;

FIG. 8 is a front view of a printhead according to a preferred embodiment of the present invention;

FIG. 9 is a cross-sectional view taken along line A-A of FIG. 8;

FIG. 10 is a front view of a preferred embodiment of the connector and heater head of the present invention;

FIG. 11 is a cross-sectional view taken along line B-B of FIG. 10;

FIG. 12 is a perspective view of a feeding assembly in accordance with a preferred embodiment of the present invention;

FIG. 13 is a front view of a feeding assembly in accordance with a preferred embodiment of the present invention;

FIG. 14 is a cross-sectional view taken along line C-C of FIG. 13;

fig. 15 is a perspective view of the filament outlet head in the preferred embodiment of the present invention;

FIG. 16 is a cross-sectional view of the filament outlet in the preferred embodiment of the present invention;

wherein: three-dimensional printer-1, upper shield-11, side shield-12, lower shield-13, linear guide rail-14, wire storage wheel-15, control device-16, upright post-17, feeding device-2, conveying wheel-21, pinch roller-22, movable support-23, elastic part-24, mounting block-25, limiting part-26, feeding pipe-27, fixed support-28, rotating shaft-29, printing head-3, connecting body-31, accommodating hole-311, top hole-312, top wire-313, heat dissipation cavity-314, heat dissipation hole-315, heat dissipation groove-316, feeding part-32, inner lining-321, outer lining-322, heat dissipation pattern-323, tapered hole-324 and screw thread-325, heating head-33, threaded hole-331, mounting hole-332, filament outlet head-34, mixing groove-341, mixing protrusion-342, discharge nozzle-343, external thread-344, support body-35, heater-36, cooling fan-4, connector-5, consumable-6 and mounting flange-7.

Detailed Description

In order to make the technical solution of the present invention better understood, the technical solution of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall belong to the protection scope of the present invention.

As shown in fig. 1 to 3, the three-dimensional printer 1 of the present embodiment includes a frame, and an upper protection cover 11, a lower protection cover 13, and a side protection cover 12, which partially cover the frame. The frame is the main part of this printer, comprises three aluminium alloy stand columns 17 and three upper and lower aluminium alloy plates, forms a triangular prism type frame, and intensity high stability is good, shock resistance is strong, weight is light in the transport. Three aluminum profile upright posts 17 of the rack are uniformly stressed according to regular triangles, a linear guide rail 14 is respectively arranged in each upright post 17, a synchronous belt pulley is respectively arranged at the top of each upright post 17 and corresponds to the synchronous belt pulley on the shaft of three driving motors at the lower part of each upright post 17, the three driving motors are arranged on an aluminum alloy plate below each upright post 17, three synchronous belts are respectively bridged on three groups of synchronous belt pulleys, and three sliding blocks on the linear guide rail 14 are driven by the three synchronous belts to move up and down along the upright posts 17. The three sliders are connected with the three groups of connecting rods in a hinge mode, the connecting rods are also connected with the mounting flange 7 on the printing head 3 in a hinge mode, and the sliders move to drive the printing head 3 to do plane motion and up-and-down motion, so that the printing work of the printing head 3 is realized.

Except for fixing the position of the upright post 17, the aluminum alloy plate on the uppermost surface of the rack forms an upper protective cover 11 through flanging, so that the belt wheel on the upper part of the upright post 17 is protected; the aluminum alloy plate in the middle of the rack not only has the function of a supporting upright post 17 and forms an electrical installation chamber with the aluminum alloy plate at the bottom, but also has the function of a workbench, and a product is printed on the aluminum alloy plate; the aluminum alloy plate at the bottom of the rack is a mounting plate of the upright post 17, and a support bottom plate of the rack is a support plate of the whole printer and supports the printer to stably work, besides the upright post 17, the driving motor and the electric components are mounted. A control device 16 is also installed between the lowest aluminum alloy plate and the working table.

The outer side of the upright post 17 of the printer is provided with a protective cover, so that the printer can prevent the printer from being scalded and mistakenly entering a printing area, and the printed product is prevented from being damaged. The protective cover occupies a large space of the printer, three sets of feeding devices 2 and three storage wheels 15 are arranged on the protective cover, the using condition of a printing material can be visually known in the printing process, and the three sets of feeding devices 2 are arranged outside the protective cover and are easy to replace the printing material, as shown in figures 1-3.

As shown in fig. 4, the feeding device 2 of the printer includes a feeding mechanism for feeding materials and a pressing mechanism for pressing the consumable 6 against the feeding mechanism, which are mounted on the side shield 12. Wherein, the conveying mechanism comprises a servo drive motor and a conveying wheel 21 arranged on the end part of a motor shaft; the pressing mechanism comprises a pressing wheel 22 for pressing the consumables 6 and the conveying wheel 21, an elastic piece 24 for providing the tendency of the pressing wheel 22 to press the conveying wheel 21, and a movable support 23 rotatably arranged on the fixed plate through a rotating shaft 29. The pinch roller 22 is used for compressing the consumables 6 and the conveying wheel 21, compressing the consumables 6 and the conveying wheel 21 through the compressing effect of the pinch roller 22, and continuously and stably conveying the consumables 6 through the conveying wheel 21.

The movable bracket 23 includes a vertical portion and a horizontal portion, a joint of the vertical portion and the horizontal portion is rotatably connected to the fixed plate through a rotation shaft 29, the pinch roller 22 is installed at a top end of the vertical portion, and the elastic member 24 acts on an end of the horizontal portion away from the rotation shaft 29. In this embodiment, the horizontal portion of the movable support 23 is also provided with a hole for the consumable substance 6 to pass through, so that the movement of the consumable substance 6 can be further limited.

The pinch roller 22 and the elastic member 24 are respectively installed at both end portions of the movable bracket 23. And a fixed bracket 28 is fixed on the side shield 12, the fixed bracket 28 is provided with a mounting block 25 corresponding to the elastic member 24, the upper end of the elastic member 24 acts on the mounting block 25, and the lower end of the elastic member 24 acts on the movable bracket 23. The mounting block 25 is stationary and the elastic member 24 fixed thereon abuts against the horizontal portion of the fixed bracket 28, so that the pinch roller 22 on the vertical portion of the fixed bracket 28 always pinches the consumable 6 against the feed roller 21.

The mounting block 25 is further provided with a limiting member 26 for limiting the elastic member 24, and the elastic member 24 is sleeved outside the limiting member 26. The elastic member 24 is preferably a spring, the retaining member 26 is preferably a screw, and the spring is sleeved outside the screw to limit the stretching or compressing movement of the spring.

In this embodiment, the fixed bracket 28 is further provided with a feeding pipe 27 through the joint 5, the fixed bracket 28 is provided with a conveying hole corresponding to the joint 5, and the consumable 6 enters the feeding pipe 27 through the conveying hole. Namely, the fixed support 28 is provided with a conveying hole, the joint 5 is arranged above the conveying hole, the joint 5 is connected with a feeding pipe 27, and the feeding pipe 27 extends to the printing head 3. The consumable 6 (printing wire) is discharged from the storage wheel 15, enters between the conveying wheel 21 and the pinch roller 22 through the movable support 23, is driven by the conveying wheel 21 to be conveyed forwards, enters the feeding pipe 27 through the conveying hole, and then moves forwards to the printing head 3.

The conveying wheel 21 in this embodiment is a gear; a limiting groove used for limiting the movement of the consumable 6 is formed in the pinch roller 22, and the limiting groove is formed along the circumferential direction of the pinch roller 22. Set up the spacing groove and make consumptive material 6's motion can be spacing, follow the slot motion all the time, prevent the off tracking, cause and carry badly.

When the printer works, the servo motor rotates proportionally under the control of a program, the conveying wheels 21 on the motor shaft respectively push the consumables 6 (printing wires) with three colors on the storage wheel 15 into the feeding pipe 27 and feed the consumables into the printing head 3, the heaters 36 in the printing head 3 heat the consumables, the consumables are melted and mixed in the wire outlet head 34, and finally, the mixed printing materials are extruded from the wire outlet 343, and the printing head 3 finishes the printing work.

The feeding device 2 is an important part of the printer and directly influences the printing quality of the printer, when the feeding device 2 works, the consumable materials 6 on the material storage wheel 15 pass through the space between the conveying wheel 21 and the pressing wheel 22, the pressing wheel 22 on the movable support 23 presses the printing wires on the conveying wheel 21 through the tension spring, the conveying wheel 21 pushes the printing wire materials into the feeding pipe 27 according to the friction force, and the three feeding pipes 27 feed the printing wire materials into the printing head 3 in proportion to be heated, melted and mixed, and finally the printing wire materials are extruded out from the wire outlet 343.

The structure of the multi-color mixing printhead 3 in the present embodiment will be described in detail below by taking the three-color mixing printhead 3 as an example.

The mixed printer head 3 of three-colour is sent into printer head 3 simultaneously with the printing material of three kinds of colours, mixes in the 34 inner chambers of silk thread head through heating and melting, extrudes mixed printing material by silk thread head after mixing, and the printing material of three primary colours mixes according to different proportions, can generate rich colorful full-colour printing material.

As shown in fig. 5 to 16, the mixing printhead 3 in this embodiment includes a connecting body 31 and a heating head 33 which are matched with each other, a feeding member 32 connected to the connecting body 31 and the heating head 33, and a filament outlet 34 mounted on the heating head 33, wherein a mixing tank 341 communicating with the feeding member 32 and a filament outlet 343 located below the mixing tank 341 are formed in the filament outlet 34, the mixing tank 341 is spirally distributed on an inner wall of the filament outlet 34, and the inner wall has a mixing protrusion 342 protruding toward the mixing tank 341. The mixing grooves 341, which are spirally distributed, and the mixing protrusions 342, which are formed, can further enhance the mixing effect.

The connector 31 is provided with a heat dissipation structure, the heat dissipation structure comprises a heat dissipation hollow 314 arranged in the connector 31, a heat dissipation hole 315 arranged on the connector 31 and a heat dissipation cavity 316, the heat dissipation hole 315 is communicated with the heat dissipation hollow 314 and an external space, and the heat dissipation cavity 316 is arranged on the outer surface of the connector 31. The heat dissipation structure formed by the heat dissipation hollow 314, the heat dissipation hole 315 and the heat dissipation cavity 316 enables the heat on the connection body 31 to be dissipated quickly.

The feeding member 32 includes an inner liner 321 inside and an outer liner 322 covering the inner liner 321, and the inner liner 321 is made of a material having a thermal conductivity smaller than that of the outer liner 322. By providing the feeding member 32 as a composite structure of the inner liner 321 and the outer liner 322, heat transfer from the heating tip 33 to the connecting body 31 is further reduced, and energy loss of the heating tip 33 is reduced.

The bottom end of the outer bushing 322 is provided with a thread 325 for connecting with the tap 34, the heating tip 33 is correspondingly provided with a threaded hole 331, the connecting body 31 is provided with a receiving hole 311 for mounting the outer bushing 322, the receiving hole 311 coincides with the axial lead of the corresponding threaded hole 331, the heating tip 33 is further provided with a mounting hole 332 for mounting the tap 34, and the intersection point of the axial leads of the plurality of threaded holes 331 is located on the axial lead of the mounting hole 332, as shown in fig. 9 and 11, wherein the included angle between the axial leads of the receiving hole 311 and the threaded hole 331 and the vertical direction is 17 °. The angles of the three feeding parts 32 are consistent, the same feeding resistance is guaranteed, the yarn discharging ratio is guaranteed, the mixing is uniform, the yarn discharging is smooth, and a good printing effect is achieved.

The outer wall of the outer bushing 322 is provided with a heat dissipation groove 323 along the circumferential direction of the outer bushing 322, so that heat on the outer bushing 322 and the connecting body 31 can be dissipated more quickly. The end of the outer bushing 322 remote from the thread 325 is provided with a tapered bore 324, the angle formed by the tapered bore 324 being 60 °. The tapered bore 324 has a tapered surface facing away from the inner liner 321, and a step is formed between the tapered surface and the outer liner 322 for abutting against the inner liner 321. The tapered hole 324 is used to allow the consumable 6 to enter the inner liner 321 more smoothly, and the step is used to abut against the inner liner 321 to fix the position of the inner liner 321 in the outer liner 322.

A top hole 312 is opened in the connecting body 31 corresponding to the receiving hole 311, and a top thread 313 for fixing the outer bushing 322 to the connecting body 31 is provided in the top hole 312. The feeding member is fixed to the connecting body 31 by the engagement of the top hole 312 and the top thread 313.

The connecting body 31 and the heating tip 33 in this embodiment are formed integrally and then separated. With this arrangement, the angle of the receiving hole 311 in the connecting body 31 is made to coincide with the angle of the screw hole 331 in the heating tip 33, and the intersection of the axial lines of the receiving hole 311 and the screw hole 331 is made to be located on the axial line of the mounting hole 332.

In this embodiment, a support 35 is further mounted above the connecting body 31, and the cooling fan 4 is mounted on the support 35. The funnel-shaped support body 35 is connected to the connecting body 31 of the print head 3 by means of a screw 325, the cooling fan 4 is installed at the upper end of the funnel-shaped support body 35, and cold air is blown into the connecting body 31 of the print head 3 to cool the connecting body 31 of the print head 3, thereby cooling the feeding member 32.

The print head 3 has three connectors 5 arranged uniformly on the connector 31, which is connected to three feeding pipes 27 extending from the feeding device 2, and three feeding components 32 corresponding to the connectors 31 are arranged inside the connector 31. The feeding unit 32 is a core unit of the print head 3, and affects whether the yarn is smoothly discharged from the yarn discharge head 34, whether the yarn is easily threaded during the feeding, and the like.

The thermal sensor is provided in the heating head 33, and can directly detect the temperature of the printing head 3. The heating head 33 is connected with the connector 31 through three feeding components 32, and due to the special structure and material of the heating components in the embodiment, the heat of the heating head 33 is transmitted to the connector 31 as little as possible, so that the heat loss is avoided, and the consumable printing material 6 is melted on the filament outlet head 34 to the maximum extent. Below the heating head 33 is a filament outlet 34, the filament outlet 34 being connected to the heating head 33 by means of an external thread 344, the filament outlet 34 being a critical component of the print head 3, the melting and mixing of the material taking place inside the filament outlet 34, which directly affects the print quality.

The connecting body 31 is a basic component of the print head 3, and each functional component of the print head 3 is mounted on the component, as shown in fig. 5-11, the component is made of an aluminum alloy material, the weight is light, the heat transfer is fast, the interior of the component is designed into a heat dissipation hollow 314 with a hollow structure, a heat dissipation hole 315 is formed in the heat dissipation hollow 314, a heat dissipation cavity 316 is further arranged on the periphery of the component, heat of the connecting body 31 can be taken away by cold air, and the temperature of a feeding pipe in the connecting body 31 can be reduced. The connecting body 31 is light in weight, so that the movement inertia of the printing head 3 is reduced, the reversing impact vibration is reduced, the noise is reduced, the printing speed is increased, and the printing quality is improved.

The connecting body 31 of the printing head 3 has a complex structure and high processing precision, the feeding pipe 27 and the feeding connector 5 are arranged on the upper part of the connecting body 31, the feeding part 32 is arranged in the connecting body, and the fan is arranged to cool the connecting body 31 so as to keep the connecting body 31 in a low-temperature state. The lower part of the connecting body 31 is a heating part, which needs to be kept in a high temperature state to melt the printing material inside the filament head 34, and the connecting body 31 and the heating head 33 are integrally formed and then cut to form an upper part and a lower part of the connecting body 31 and the heating head 33, so that the heat transfer between the high temperature part and the low temperature part is not carried out. Three containing holes 311 for installing the feeding components 32 are uniformly distributed in the connector 31, if an integrated processing technology is not adopted, the angles of the three feeding pipes are possibly inconsistent, the resistance of feeding materials with inconsistent angles is also inconsistent, the proportion of mixed materials is inaccurate, and the quality of printing colors is influenced. The 3M 6 screw holes 331 of the heating tip 33 correspond to the receiving holes 311 of the connecting body 31, and if the positions, angles, and receiving holes 311 of the upper connecting body 31 of the screw holes 331 of the heating tip 33 do not coincide, the printhead 3 cannot be assembled. And the mounting hole 332 of the filament outlet head 34 on the heating head 33 influences the filament outlet ratio and the printing quality no matter the side is deviated at the intersection of the axial lines of the three threaded holes 331. In this embodiment, the receiving holes 311 of the three feeding units of the connecting body 31 are at an angle of 17 ° with the axial line of the print head 3, and the 3M 6 threaded holes 331 on the heating head 33 are at an angle of 17 ° with the axial line of the print head 3. The degree is too small, the structural arrangement is difficult, the degree is too large, the resistance is large, and the yarn is not smooth and easy to discharge.

The print head 3 is a separate component and for ease of assembly and maintenance, the print head 3 is mounted to the mounting flange 7 of the frame and is attached by 3M 3 screws.

In the prior art, before the printing material enters the heating head 33, heat conducted out by the heating head 33 can be transmitted into the feeding part, so that the temperature of the feeding part rises to cause the printing material to soften, the softened printing material is influenced by resistance of the wire outlet 343, the diameter of the printing material can become large, resistance of the printing material with the increased diameter in the feeding pipe becomes large, the resistance becomes larger and larger, the diameter of the printing material becomes larger and larger, the printing material can be clamped in the feeding pipe, unsmooth wire discharging is caused, and then the part has a blockage fault.

As shown in fig. 9 and 12-14, the feeding member 32 is a composite structure composed of two parts, including an inner liner 321 inside and an outer liner 322 outside, wherein the inner liner 321 is made of a ceramic material or a glass material, and a teflon material is also used when printing the low-temperature consumable 6, so that the inner hole of the inner liner 321 needs to be smooth, the sliding friction coefficient is low, and the feeding resistance is low. An inner liner 321 with a bore diameter of 2mm prints 1.75mm in diameter. The outer bushing 322 is made of stainless steel material, so as to meet the requirements of high temperature resistance, fast heat dissipation and high strength.

The feeding member 32 is installed between the heating head 33 and the feeding pipe 27, one end of the feeding member 32 is a male screw 344 of M6 and is connected with the heating head 33 of the printing head 3, the other end is embedded in the accommodating hole 311 of the connecting body 31, and the periphery of the stainless steel outer bushing 322 is provided with a heat dissipation groove 323, so that heat conduction is reduced to the maximum extent, and heat dissipation is accelerated. The inner portion of the outer liner 322 has a step for blocking the inner liner 321 from moving, and the inner tapered surface of the outer liner 322 can guide the printing material to smoothly enter the inner liner 321, which is beneficial to replacing the printing material.

The heating head 33 of the three-color mixing head 3 is provided with the filament discharging head 34 through the mounting hole 332, the printing material enters the feeding part from the feeding pipe and then enters the filament discharging head 34 to be heated, the hot-melted material is mixed and advanced in the mixing groove 341 of the filament discharging head 34, and the mixed material is directly extruded from the filament outlet 343 of the filament discharging head 34, as shown in fig. 15 to 16.

In the prior art, three color printing materials enter the filament outlet head 34 to be heated, and the three materials which are heated and melted are mixed in the filament outlet head 34. Therefore, the filament outlet head 34 is redesigned, the filament outlet head 34 with better mixing function is manufactured, the mixing contact distance is increased, and the mixing is strengthened through overturning.

The diameter of the inner cavity of the filament outlet head 34 in the embodiment is relatively reduced compared with the existing filament outlet head 34, and the spiral mixing groove 341 is added, so that the melted materials are mixed and advance along the mixing groove 341, the contact length of the three materials after being melted is increased, the mixing protrusion 342 is added, and the mixing effect is enhanced.

In this embodiment, the diameter of the printing consumable 6 is 1.75mm, the lead of the mixing tank 341 is 4.5mm, the rotation is 1.5 turns, and the filament outlet diameter of the filament outlet 343 is 0.3 mm. The ratio of the consumable material 6 to the filament outlet 343 is about 6:1, the discharging is 6 times faster than the feeding, the mixing effect is also increased by 6 times, and the filament outlet head 34 of the embodiment has better color mixing effect, smooth filament outlet and other effects.

The mixing tank 341 has a small lead, a large tapping resistance, a poor tapping smoothness, and a delayed color mixing. The mixing tank 341 with too large lead does not perform the mixing function, and the lead of the mixing tank 341 should give consideration to both the uniformity of color mixing and the smoothness of yarn discharge, and also the hysteresis of color mixing. The lead of the mixing tank 341 is set to 4.5mm in the present embodiment, and the above-described problem can be solved. In addition, the tap 34 in this embodiment is made of titanium alloy material, so that the tap 34 has fast heat transfer, high wear resistance, high corrosion resistance and high strength, and is mounted with the heating head 33 by a thread 325.

The three-dimensional printer 1 in this embodiment has the following advantages over the prior art:

1. the connecting body 31 and the heating head 33 are integrally molded: the integral structure is processed, after the processing is finished, the connecting body and the heating head are formed by cutting, so that the angles and the positions of the three accommodating holes 311 are consistent, and the intersection point of the axial lines is positioned on the axial line of the screw hole of the screw head 34; only by the integrated structure of the connecting body 31 and the heating head 33, the feeding structure with multiple inclined feeding components can be manufactured, the feeding resistance is minimum, and the feeding proportion is accurate;

2. the feed tube 27 forms an angle with the axis of the print head 3 for mixing the three colors of the print head 3: the multi-color mixing printing head 3 has a plurality of feeding parts, the feeding resistance is large when the printing head is vertically arranged, the yarn is not smooth, and the printing quality is influenced; the feeding part and the axis of the printing head 3 form a certain included angle (17 degrees), a plurality of feeding pipes 27 are symmetrically distributed, the feeding is not turned, the structural resistance is minimum, the wire outlet is smooth, and the structure is compact;

3. the inner cavity of the filament outlet head 34 is designed into a spiral structure: a spiral mixing tank 341 is formed inside the filament outlet head 34, the contact length of the three materials after melting is lengthened, the mixing protrusion 342 of the mixing tank 341 increases the material mixing, and the mixing effect is good;

4. composite structure of the feeding member 32: one end of the feeding component 32 is connected with the heating head 33, the other end of the feeding component is connected with the feeding pipe 27, the heat of the heating head 33 is transmitted into the feeding component 32, so that the printing material in the feeding component 32 is softened and is influenced by the resistance of the wire outlet 343, the diameter of the printing material is increased, the larger the feeding resistance is, the thicker the diameter is, and the printing material can be clamped in the feeding pipe and can not be discharged; the above problem is solved by the composite structure of the inner liner 321 and the outer liner 322 in the present embodiment;

5. the feeding device 2: the consumable 6 is tightly pressed with the conveying mechanism through the pressing wheel 22, so that the conveying mechanism can continuously and stably convey the consumable 6, the feeding is reliable, the conveying is avoided being poor, and the wire discharging is not smooth.

The above embodiments are only for illustrating the technical concept and features of the present invention, and the purpose thereof is to enable those skilled in the art to understand the contents of the present invention and to implement the present invention, so as not to limit the protection scope of the present invention, and all equivalent changes or modifications made according to the spirit of the present invention should be covered by the protection scope of the present invention.

Claims (10)

1. The utility model provides a feeding device, its characterized in that, including the fixed plate, be used for carrying out the conveying mechanism of pay-off and be used for with the consumptive material with the hold-down mechanism that conveying mechanism compresses tightly, conveying mechanism and hold-down mechanism are fixed on the fixed plate, hold-down mechanism is including being used for compressing tightly the pinch roller that consumptive material and conveying mechanism compressed tightly and being used for providing the pinch roller compresses tightly the elastic component of conveying mechanism trend.

2. The feeding device as claimed in claim 1, wherein the conveying mechanism comprises a motor and a conveying wheel at the end of the output shaft of the motor, and the compressing wheel is used for compressing the consumable with the conveying wheel.

3. The feeding device as claimed in claim 1, wherein the pressing mechanism further includes a movable bracket rotatably disposed on the fixed plate, and the pressing wheel and the elastic member are respectively mounted at two end portions of the movable bracket.

4. The feeding device as claimed in claim 3, wherein the movable bracket comprises a vertical part and a horizontal part, the joint of the vertical part and the horizontal part is rotatably connected to the fixed plate through a rotating shaft, the pressing wheel is mounted at the top end of the vertical part, and the elastic member acts on one end of the horizontal part far away from the rotating shaft.

5. The feeding device as claimed in claim 4, wherein a fixed bracket is fixed on the fixed plate, a mounting block is mounted on the fixed bracket corresponding to the elastic member, one end of the elastic member acts on the mounting block, and the other end of the elastic member acts on the movable bracket.

6. The feeding device as claimed in claim 5, wherein the mounting block is further provided with a limiting member for limiting the elastic member, and the elastic member is sleeved outside the limiting member.

7. The feeding device as set forth in claim 5, wherein the feeding device comprises a feeding pipe, a joint is mounted on the fixed support, and the feeding pipe is connected to the joint.

8. The feeding device as claimed in claim 7, wherein the fixing bracket is provided with a delivery hole corresponding to the joint, and the consumable enters the feeding pipe through the delivery hole.

9. The feeding device as set forth in claim 2, wherein the conveying wheel is a gear; the pinch roller is provided with a limiting groove used for limiting the movement of consumables, and the limiting groove is formed along the circumferential direction of the pinch roller.

10. A three-dimensional printer comprising the feeding device according to any one of claims 1 to 9.

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