3D printing extrusion mechanism based on water-based slurry and 3D printing device

Abstract

The embodiment of the invention discloses a 3D printing extrusion mechanism based on water-based slurry and a 3D printing device. The 3D printing extrusion mechanism comprises an extrusion material barrel, an extrusion lead screw, an extrusion push block, a stirring head, a stirring blade assembly, a telescopic sleeve assembly and a telescopic supporting assembly. The extrusion screw rod penetrates into the extrusion charging barrel from the closed end of the extrusion charging barrel along the axial direction; the extrusion push block is in threaded connection with the extrusion screw rod; the stirring blade assembly is arranged between the stirring head and the extrusion push block and comprises a first stirring blade and a second stirring blade which are arranged in a staggered mode, and the stirring directions of the first stirring blade and the second stirring blade are opposite; the telescopic sleeve assembly comprises an inter-blade sleeve assembly and a blade tail sleeve assembly which are the same in structure, and one inter-blade sleeve assembly is mounted between each first stirring blade and the corresponding second stirring blade which are adjacent; a blade tail sleeve assembly is mounted between the stirring blade close to the extrusion push block and the extrusion push block; the telescopic supporting assembly comprises a head end supporting pad, a middle supporting pad, a tail end supporting pad and a telescopic spring. And telescopic springs are connected between the head end supporting pad and the middle supporting pads, between the adjacent middle supporting pads, and between the middle supporting pads and the tail end supporting pad.

Description

Technical Field

[0001] The present application relates to the field of 3D printing technology, and in particular to a 3D printing extrusion mechanism and a 3D printing device based on water-based slurry. Background Art

[0002] The 3D printing molding process based on water-based slurry has complex shapes of molded parts, high molding density, and a more environmentally friendly manufacturing process. However, during the printing process, the water-based slurry mainly uses water as the medium and has a low content of organic binders. When the pressure is high, relative movement of the solid and liquid phases often occurs, resulting in liquid phase migration. That is, the pressure applied to the liquid phase during the extrusion process causes the liquid to move faster than the solid particles, so that the solid particles are more like a filter, and the liquid flows between the solid particles, resulting in uneven distribution of the solid and liquid phases, which in turn causes changes in the liquid phase content in the extruded water-based slurry, affecting the molding quality.

[0003] In the prior art, the invention patent application with publication number CN116619521A discloses a ceramic 3D printer extrusion system and its use method, which uses an oscillation mechanism to oscillate the soft slurry bag, increases the motor torque, increases the slurry transmission pipe diameter, and other methods to reduce the liquid phase migration of the slurry. In the above technical scheme, appropriate oscillation improves the liquid phase uniformity of the water-based slurry in the material bag during printing, but the overall diameter of the hose connected to the extrusion end of the material bag is small, and the liquid phase migration during the extrusion process is still relatively serious; the water-based slurry with high solid content is printed by increasing the motor torque, and the liquid phase migration of the water-based slurry is reduced to a certain extent at a faster printing speed, but the faster printing speed cannot effectively guarantee its printing accuracy during the printing process; the method of increasing the slurry transmission pipe diameter reduces the liquid phase migration of the water-based slurry during the transmission process, but during printing, the print head and the slurry transmission pipe diameter are quite different, and the existence of the liquid phase dead angle affects the normal liquid phase migration of the water-based slurry to a certain extent, reducing the molding quality during the printing process.

[0004] Therefore, there is an urgent need for a 3D printing device that can effectively solve the liquid phase migration phenomenon during the extrusion of water-based slurry and make the liquid phase of the extruded slurry uniformly distributed. Summary of the invention

[0005] In order to solve at least one of the problems mentioned in the background technology, the embodiments of the present application provide a 3D printing extrusion mechanism and a 3D printing device based on a water-based slurry, which can continuously stir the water-based slurry during the extrusion process, promote uniform distribution of the liquid phase, and effectively solve the liquid phase migration phenomenon during the extrusion process of the water-based slurry.

[0006] In order to achieve the above-mentioned purpose, the first aspect of the embodiment of the present application provides a 3D printing extrusion mechanism based on water-based slurry, including an extrusion barrel, an extrusion screw, an extrusion push block, a stirring head, a stirring blade assembly, a telescopic sleeve assembly and a telescopic support assembly;

[0007] One end of the extrusion barrel is provided with a liquid inlet and outlet, and the other end of the extrusion barrel is closed;

[0008] The extrusion screw rod axially passes through the closed end of the extrusion barrel into the extrusion barrel, one end of the extrusion screw rod extending out of the closed end of the extrusion barrel is connected to the power member, and one end of the extrusion screw rod located in the extrusion barrel is arranged near the liquid inlet and outlet and connected to the stirring head;

[0009] The extrusion push block is threadedly connected to the extrusion screw rod, and the outer wall surface of the extrusion push block is slidably connected to the inner wall surface of the extrusion barrel, and an axial limiting structure is arranged between the extrusion barrel and the extrusion push block;

[0010] The stirring blade assembly is arranged between the stirring head and the extrusion push block, and the stirring blade assembly includes a first stirring blade and a second stirring blade arranged alternately, the stirring directions of the first stirring blade and the second stirring blade are opposite, and the first stirring blade and the second stirring blade are both provided with a central hole with a gap with the extrusion screw rod, and the stirring blade close to one end of the stirring head is rotatably engaged with the outer periphery of the stirring head;

[0011] The telescopic sleeve assembly comprises an inter-blade sleeve assembly and a blade tail sleeve assembly of the same structure, and the inter-blade sleeve assembly comprises an odd number of sleeves, and the odd number of sleeves are mounted outwards layer by layer from both sides with the sleeve located in the middle as the inner layer;

[0012] An inter-blade sleeve assembly is installed between the adjacent first stirring blades and the second stirring blades, the sleeves at both ends of the inter-blade sleeve assembly are respectively slidably connected to the center holes of the adjacent stirring blades, and the ports of the corresponding center holes are provided with anti-slip limit blocks to prevent the inter-blade sleeve assembly from slipping off;

[0013] The blade tail sleeve assembly is installed between the stirring blade close to the extrusion push block and the extrusion push block, the sleeve of the blade tail sleeve assembly close to the stirring blade is slidably connected with the center hole of the corresponding stirring blade, and an anti-slip limit block is arranged at the port of the corresponding center hole to prevent the blade tail sleeve assembly from slipping off, and the sleeve of the blade tail sleeve assembly close to the extrusion push block is used to abut against the extrusion push block;

[0014] The telescopic support assembly comprises a head end support pad, an intermediate support pad, a tail end support pad and a telescopic spring, and the extrusion screw rod is provided with at least two slide grooves extending along the axial direction; one side of the head end support pad is embedded in the preset central blind hole of the stirring head, and the other side of the head end support pad is embedded in the slide groove at the end of the extrusion screw rod; each of the inter-leaf sleeve assemblies is installed in the sleeve away from the stirring head side of the intermediate support pad, the outer periphery of the intermediate support pad is supported by the inner wall surface corresponding to the sleeve, and the center of the intermediate support pad surrounds the extrusion screw rod and is slidably connected to the slide groove; the tail end support pad is installed in the sleeve away from the stirring head side of the blade tail sleeve assembly, the outer periphery of the tail end support pad is supported by the inner wall surface corresponding to the sleeve, and the end face of the tail end support pad away from the stirring head side is used to abut against the extrusion push block, and the center of the tail end support pad surrounds the extrusion screw rod and is slidably connected to the slide groove;

[0015] A telescopic spring is connected between the head end support pad and the middle support pad, between adjacent middle support pads, and between the middle support pad and the tail end support pad.

[0016] In one feasible embodiment, the extrusion barrel includes a barrel and an end cover, one end of the barrel is connected to the end cover to form a closed end, and the other end of the barrel is configured as a truncated cone structure that closes away from the closed end, and a preset opening at the small end of the truncated cone structure forms the liquid inlet and outlet.

[0017] In an achievable embodiment, the power member includes a motor, the output end of the motor is fixedly connected to the output seat, one end of the extrusion screw extending out of the extrusion barrel is fixedly connected to the screw seat, and a feedback housing is arranged on the periphery of the output seat and the screw seat;

[0018] The end surfaces of the output seat and the screw seat that are close to each other are respectively provided with overhanging edges, the overhanging edges of the output seat and the overhanging edges of the screw seat are arranged in a sleeve arrangement, and a torsion spring is installed between the corresponding overhanging edges;

[0019] An encoder grid is arranged at the periphery of the output seat, an encoder light source is arranged at the periphery of the screw seat, a photosensitive element is arranged on the feedback housing, and an output end of the photosensitive element is electrically connected to a control end of the power part.

[0020] In a feasible embodiment, a retaining spring gasket surrounding the central blind hole is arranged between the stirring head and the head end support pad, the outer periphery of the retaining spring gasket extends out of the outer periphery of the end face of the stirring head, and an annular groove matching the retaining spring gasket is arranged near the central hole of the stirring blade of the stirring head.

[0021] In a feasible embodiment, in the inter-blade sleeve assembly, the sleeves on both sides are symmetrically mounted outwardly layer by layer on the sleeve located in the middle, and adjacent sleeves are limited to each other by circumferentially extending annular limit edges; at least one of the two annular limit edges arranged on the sleeve located in the middle is detachably connected to the corresponding sleeve.

[0022] In a feasible embodiment, an intermediate support limit block is provided at the port of the sleeve of the intermediate support pad corresponding to the inter-blade sleeve assembly to prevent the intermediate support pad from falling out, and a tail end support limit block is provided at the port of the sleeve of the tail end support pad corresponding to the tail end support pad of the blade tail sleeve assembly to prevent the tail end support pad from falling out, and a sliding limit block is provided at the preset position of the slide groove to limit the displacement of the tail end support pad.

[0023] In a feasible embodiment, a slideway is provided on one of the inner wall surface of the extrusion barrel and the outer wall surface of the extrusion push block, and a slide bar is provided on the other of the inner wall surface of the extrusion barrel and the outer wall surface of the extrusion push block, and the slideway slidably cooperates with the slide bar.

[0024] A second aspect of an embodiment of the present application provides a 3D printing device based on water-based slurry, including the above-mentioned 3D printing extrusion mechanism based on water-based slurry.

[0025] In an achievable embodiment, a pressurizing mechanism is further included, wherein the pressurizing mechanism includes a thick tube solenoid valve, a first thick feed tube, a first pressurizing barrel, a second thick feed tube, a second pressurizing barrel, a first thin feed tube, a second thin feed tube, and a thin tube solenoid valve;

[0026] The liquid inlet and outlet of the extrusion barrel of the water-based slurry-based 3D printing extrusion mechanism are connected to the inlet of the thick tube solenoid valve, the first outlet of the thick tube solenoid valve is connected to the first pressurized barrel through the first feed thick tube, and the second outlet of the thick tube solenoid valve is connected to the second pressurized barrel through the second feed thick tube; the outlet of the first pressurized barrel is connected to the first inlet of the capillary solenoid valve through the first feed capillary tube, the outlet of the second pressurized barrel is connected to the second inlet of the capillary solenoid valve through the second feed capillary tube, and the outlet of the capillary solenoid valve is connected to the extrusion head.

[0027] In an achievable embodiment, it further includes an extrusion head motion mechanism, wherein the extrusion head motion mechanism includes a gantry frame, an extrusion head, a Y-axis motion member, an X-axis motion member, and a Z-axis motion member;

[0028] The gantry frame comprises a base, a crossbeam and two vertical beams, the two vertical beams are arranged oppositely on the base, and the crossbeam is connected to the upper parts of the two vertical beams;

[0029] The feed end of the extruder head is connected to the outlet of the capillary solenoid valve through a discharge capillary tube; the extruder head is arranged on a Y-axis sliding member at the crossbeam, the Y-axis sliding member is connected to the Y-axis moving member, and the Y-axis moving member is controlled to drive the extruder head to move along the extension direction of the crossbeam;

[0030] A Z-axis sliding plate is arranged between the two vertical beams, the Z-axis sliding plate extends in a horizontal direction and is connected to a Z-axis moving part, and the Z-axis moving part is controlled to drive the Z-axis sliding plate to move in the extending direction of the vertical beams;

[0031] An X-axis sliding plate is arranged above the Z-axis sliding plate, and the X-axis sliding plate extends in a horizontal direction and is connected to an X-axis moving part, and the X-axis moving part is controlled to drive the X-axis sliding plate to move in an X-axis direction, and the X-axis direction is perpendicular to the extension direction of the horizontal beam and the vertical beam.

[0032] The embodiment of the present application provides a 3D printing extrusion mechanism based on water-based slurry and a 3D printing device. The 3D printing extrusion mechanism based on water-based slurry includes an extrusion barrel, an extrusion screw, an extrusion push block, a stirring head, a stirring blade assembly, a telescopic sleeve assembly and a telescopic support assembly. The 3D printing device of water-based slurry includes the above-mentioned 3D printing extrusion mechanism based on water-based slurry.

[0033] Among them, when filling the extrusion mechanism, it is necessary to reversely load the water-based slurry into the extrusion barrel. Specifically, first, the operating power piece drives the extrusion screw so that the extrusion push block moves in the direction away from the inlet and outlet of the liquid material under the joint action of the extrusion screw and the axial limit structure until it is close to the closed end of the extrusion barrel, and sufficient filling space is reserved in the extrusion barrel. At this time, the telescopic springs between the support pads are in a slightly compressed or freely extended state, the middle support pad is supported in the sleeve of the inter-leaf sleeve assembly near the closed end, and the tail end support pad is supported in the sleeve of the tail sleeve assembly near the closed end. Under the support and drive of the telescopic support assembly, the telescopic sleeve assembly is in an extended state, and the stirring blades are spaced apart with the help of the anti-slip limit block. Secondly, the prepared water-based slurry is loaded into the syringe of the appropriate model of the dispensing machine, and the syringe of the dispensing machine is connected to the air pump so that the discharge port of the syringe of the dispensing machine is aligned with the liquid inlet and outlet of the extrusion barrel. Finally, turn on the air pump and slowly and evenly load the water-based slurry in the syringe of the dispensing machine into the extrusion barrel until the extrusion barrel is filled.

[0034] After the water-based slurry is loaded, extrusion can be carried out. Specifically, the operating power part drives the extrusion screw, so that the extrusion push block moves in the direction close to the liquid inlet and outlet under the joint action of the extrusion screw and the axial limiting structure. In this process, since the stirring blades of the stirring blade assembly are distributed at intervals, slidingly connected with the telescopic sleeve assembly, and rotatingly engaged with the stirring head, and the stirring directions of adjacent stirring blades are opposite, the water-based slurry is subjected to the force of the extrusion push block, driving the stirring blades to rotate freely. The stirring blades stir the water-based slurry to evenly distribute the solid and liquid phases and avoid liquid phase migration. The evenly stirred water-based slurry is extruded from the liquid inlet and outlet under the thrust of the extrusion push block.

[0035] As the extrusion push block moves toward the direction of the liquid inlet and outlet, the extrusion push block contacts the tail support pad, and the tail support pad compresses the telescopic spring connected to it, and the telescopic spring drives the middle support pad connected to it to move, and so on, each telescopic spring is compressed at the same time, and then moves toward the liquid inlet. At the same time, the extrusion push block also abuts the sleeve supported by the tail support pad in the blade tail sleeve assembly, and the sleeve also moves toward the liquid inlet and outlet under the action of the extrusion push block. Furthermore, when the compression spring is further compressed, the tail support pad and the middle support pad abut against the sleeve of the next level close to the extrusion push block, pushing the corresponding sleeve assembly to gradually retract toward the liquid inlet and outlet. In this process, the packing space in the extrusion barrel gradually decreases, and the adjacent stirring blades gradually approach each other, but the adjacent stirring blades always maintain free rotation in the opposite direction of stirring, the water-based slurry is continuously stirred, and the solid and liquid phases are evenly distributed until the water-based slurry is completely extruded, avoiding the phenomenon of liquid phase migration during the extrusion process.

[0036] The extrusion screw in the embodiment of the present application provides power for the extrusion push block. A stirring blade assembly is installed between the stirring head and the extrusion push block, and adjacent stirring blades are rotatably connected to the telescopic sleeve assembly, which can stir the water-based slurry in different stirring directions, making the liquid phase distribution more uniform and effectively avoiding the liquid phase migration phenomenon. The telescopic support assembly supports the telescopic sleeve assembly, and then provides support for the stirring blade assembly, ensuring that a gap is maintained between the stirring blade assembly and the screw, and that they can rotate freely to prevent interference. The telescopic sleeve assembly can perform telescopic movement during use, so that the stirring blades can adapt to changes in the extrusion barrel packing space and move away from or close to each other to form a stable stirring effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0038] Figure 1 A schematic diagram of the structure of a 3D printing extrusion mechanism based on a water-based slurry provided in an embodiment of the present application;

[0039] Figure 2 for Figure 1 A cross-sectional view of the extrusion barrel portion;

[0040] Figure 3 A schematic structural diagram of a telescopic sleeve assembly in an extrusion barrel in a retracted state provided in an embodiment of the present application;

[0041] Figure 4 for Figure 3 Partial detail diagram;

[0042] Figure 5 for Figure 4 A magnified image of point A;

[0043] Figure 6 A schematic structural diagram of a telescopic sleeve assembly in an extrusion barrel provided in an embodiment of the present application in an extended state;

[0044] Figure 7 for Figure 6 Partial detail diagram;

[0045] Figure 8 A schematic diagram of the internal structure of the extrusion barrel provided in the embodiment of the present application;

[0046] Fig. 9 for Figure 1 A cross-sectional view of the connecting portion of the power part;

[0047] Fig.10 for Fig. 9 A magnified view of point B;

[0048] Fig.11 A schematic diagram of the structure of a 3D printing device based on water-based slurry provided in an embodiment of the present application;

[0049] Fig.12 for Fig.11 Structural diagram of the middle pressurizing mechanism;

[0050] Fig.13 for Fig.11 Schematic diagram of the structure of the extrusion head motion mechanism.

[0051] Description of reference numerals:

[0052] 100-3D printing extrusion mechanism;

[0053] 110-extrusion barrel; 111-barrel body; 1111-liquid inlet and outlet; 112-end cover; 113-barrel sealing ring; 114-extrusion support frame;

[0054] 120-extrusion screw rod; 121-screw rod seat; 1212-slideway; 122-extrusion push block;

[0055] 130-stirring head; 131-circlip gasket;

[0056] 140 - stirring blade assembly; 141 - first stirring blade; 142 - second stirring blade; 143 - center hole; 144 - anti-slip limit block;

[0057] 150- telescopic sleeve assembly; 151- inter-blade sleeve assembly; 152- blade tail sleeve assembly; 153- sleeve; 154- annular limit edge;

[0058] 160- telescopic support assembly; 161- head end support pad; 162- middle support pad; 163- tail end support pad; 164- telescopic spring;

[0059] 170-power part; 171-motor; 172-output seat; 173-torsion spring; 174-encoder light source; 175-encoder grid; 176-feedback housing;

[0060] 200-3D printing device;

[0061] 210-pressurizing mechanism; 211-thick tube solenoid valve; 2111-first thick feeding tube; 2112-second thick feeding tube; 212-first pressurizing barrel; 213-second pressurizing barrel; 214-pressurizing push block; 215-double-axis screw stepper motor; 216-pressurizing screw; 217-thin tube solenoid valve; 2171-first thin feeding tube; 2172-second thin feeding tube; 2173-discharging tube; 218-pressurizing support frame;

[0062] 220-extrusion head movement mechanism; 221-gantry frame; 222-base; 223-crossbeam; 224-vertical beam; 225-extrusion head; 226-Y-axis sliding member; 227-X-axis sliding plate; 228-Z-axis sliding plate. DETAILED DESCRIPTION

[0063] In order to make the purpose, technical solution and advantages of the present application clearer, the technical solution in the embodiment of the present application will be described in more detail below in conjunction with the drawings in the embodiment of the present application. It is worth noting that the embodiments described in the drawings are only part of the embodiments of the present application, not all of the embodiments. That is, the embodiments described by the drawings are exemplary and are intended to be used to explain the present application, and cannot be understood as limiting the present application.

[0064] In the process of 3D printing based on water-based slurry extrusion molding, there is often a phenomenon of liquid phase migration, that is, the pressure applied to the liquid phase during the extrusion process causes the liquid to move faster than the solid particles, making the solid particles more like a filter at this time. The liquid flows through the solid particle network, resulting in uneven distribution of solid and liquid phases, causing changes in the liquid phase content in the extruded water-based slurry. Liquid phase migration makes the initial slurry too thin during printing. As the liquid phase continues to be lost, the water-based slurry gradually loses water and becomes dry, resulting in the inability to extrude, affecting the molding quality.

[0065] The embodiments of the present application provide a 3D printing extrusion mechanism and a 3D printing device based on water-based slurry, which can continuously stir the water-based slurry, promote uniform distribution of the liquid phase, and effectively solve the liquid phase migration phenomenon during the extrusion process of the water-based slurry.

[0066] The following will be combined Figure 1-Figure 10 The 3D printing extrusion mechanism 100 based on water-based slurry provided in an embodiment of the present application is described.

[0067] The embodiment of the present application provides a 3D printing extrusion mechanism 100 based on water-based slurry, including an extrusion barrel 110, an extrusion screw 120, an extrusion push block 122, a stirring head 130, a stirring blade assembly 140, a telescopic sleeve assembly 150 and a telescopic support assembly 160.

[0068] A liquid inlet and outlet 1111 is disposed at one end of the extrusion barrel 110 , and the other end of the extrusion barrel 110 is sealed.

[0069] The extrusion screw rod 120 axially passes through the closed end of the extrusion barrel 110 into the extrusion barrel 110 , and one end of the extrusion screw rod 120 extending out of the closed end of the extrusion barrel 110 is connected to the power part 170 . The end of the extrusion screw rod 120 located in the extrusion barrel 110 is arranged near the liquid inlet and outlet 1111 and connected to the stirring head 130 .

[0070] The extrusion push block 122 is threadedly connected to the extrusion screw rod 120 , and the outer wall surface of the extrusion push block 122 is slidably connected to the inner wall surface of the extrusion barrel 110 , and an axial limiting structure is provided between the extrusion barrel 110 and the extrusion push block 122 .

[0071] The stirring blade assembly 140 is arranged between the stirring head 130 and the extrusion push block 122. The stirring blade assembly 140 includes a first stirring blade 141 and a second stirring blade 142 that are staggered. The stirring directions of the first stirring blade 141 and the second stirring blade 142 are opposite, and the first stirring blade 141 and the second stirring blade 142 are both arranged in a center hole 143 with a gap with the extrusion screw 120. The stirring blade close to one end of the stirring head 130 is rotatably clamped on the outer periphery of the stirring head 130.

[0072] The telescopic sleeve assembly 150 includes an inter-blade sleeve assembly 151 and a blade tail sleeve assembly 152 of the same structure. The inter-blade sleeve assembly 151 includes an odd number of sleeves 153. The odd number of sleeves 153 are mounted outwards layer by layer from both sides with the sleeve 153 located in the middle as the inner layer.

[0073] An inter-blade sleeve assembly 151 is installed between the adjacent first stirring blades 141 and the second stirring blades 142. The sleeves 153 located at both ends of the inter-blade sleeve assembly 151 are respectively slidably connected to the center holes 143 of the adjacent stirring blades, and anti-slip limit blocks 144 are provided at the ports of the corresponding center holes 143 to prevent the inter-blade sleeve assembly 151 from slipping.

[0074] A blade tail sleeve assembly 152 is installed between the stirring blade near the extrusion push block 122 and the extrusion push block 122. The sleeve 153 of the blade tail sleeve assembly 152 near the stirring blade is slidably connected to the center hole 143 of the corresponding stirring blade, and an anti-slip limit block 144 is provided at the port of the corresponding center hole 143 to prevent the blade tail sleeve assembly 152 from slipping. The sleeve 153 of the blade tail sleeve assembly 152 near the extrusion push block 122 is used to abut the extrusion push block 122.

[0075] The telescopic support assembly 160 includes a head end support pad 161, an intermediate support pad 162, a tail end support pad 163 and a telescopic spring 164. The extrusion screw 120 is provided with at least two slide grooves 1212 extending in the axial direction. One side of the head end support pad 161 is embedded in the preset central blind hole of the stirring head 130, and the other side of the head end support pad 161 is embedded in the slide groove 1212 at the end of the extrusion screw 120. An intermediate support pad 162 is installed in the sleeve 153 on the side away from the stirring head 130 of each interleaf sleeve assembly 151. The outer periphery of the intermediate support pad 162 is supported on the inner wall surface of the corresponding sleeve 153, and the center of the intermediate support pad 162 surrounds the extrusion screw 120 and is slidably connected to the slide groove 1212. A tail end support pad 163 is installed in the sleeve 153 on the side of the blade tail sleeve assembly 152 away from the stirring head 130, and the outer periphery of the tail end support pad 163 is supported on the inner wall surface of the corresponding sleeve 153. The end surface of the tail end support pad 163 away from the stirring head 130 is used to abut the extrusion push block 122, and the center of the tail end support pad 163 surrounds the extrusion screw 120 and is slidably connected to the slide groove 1212.

[0076] A telescopic spring 164 is connected between the head end support pad 161 and the middle support pad 162 , between adjacent middle support pads 162 , and between the middle support pad 162 and the tail end support pad 163 .

[0077] In the embodiment of the present application, the end close to the stirring head 130 is set as the front end, and the end close to the extrusion push block 122 is set as the rear end. The stirring head 130 is located at the liquid inlet and outlet 1111 of the extrusion barrel 110, and is a cylindrical structure extending along the axial direction of the extrusion barrel 110. Its front end can be conical to facilitate the water-based slurry to flow in and out along the conical surface. Its rear end is embedded with the head end support pad 161 through a preset central blind hole, and the head end support pad 161 is clamped with the extrusion screw 120.

[0078] The extrusion push block 122 is threadedly connected to the extrusion screw 120. When the extrusion screw 120 is rotated by the power member 170, the extrusion push block 122 is restricted by the axial limiting structure and moves forward and backward along the axial direction of the extrusion barrel 110 toward or away from the liquid inlet and outlet 1111.

[0079] In the embodiment of the present application, it is assumed that five groups of stirring blades are provided, the stirring blade at the front end clamped on the outer periphery of the stirring head 130 is the first stirring blade 141, the first stirring blade 141 and the second stirring blade 142 are arranged alternately, and the stirring blade at the rear end close to one end of the extrusion push block 122 is also the first stirring blade 141.

[0080] The frontmost first stirring blade 141 is rotatably connected to the outer periphery of the stirring head 130, the center hole 143 between adjacent stirring blades supports the inter-blade sleeve assembly 151, and the center hole 143 of the rearmost first stirring blade 141 supports the blade tail sleeve assembly 152. Thus, the frontmost first stirring blade 141 can rotate freely around the stirring head 130, and the stirring blades of the stirring blade assembly 140 can all rotate freely around the telescopic sleeve assembly 150.

[0081] The first stirring blade 141 and the second stirring blade 142 may both be formed by a plurality of sub-blades having a certain spiral angle, and the sub-blades of the first stirring blade 141 and the second stirring blade 142 may each form a different spiral direction. In this way, when the water-based slurry flows through the stirring blades under thrust, the stirring blades are rotated by force to form a stirring effect with a certain spiral direction, and adjacent stirring blades form different stirring spiral directions, thereby forming a uniform stirring effect on the water-based slurry.

[0082] The inter-blade sleeve assembly 151 and the blade tail sleeve assembly 152 are both formed by sleeves 153 being set layer by layer, and can telescopically move along the axial length. The inter-blade sleeve assembly 151 at the front end is supported by the head end support pad 161 and the middle support pad 162, the inter-blade sleeve assembly 151 in the middle is supported by the middle support pad 162, and the blade tail sleeve assembly 152 is supported by the tail end support pad 163. Therefore, the inter-blade sleeve assembly 151 and the blade tail sleeve assembly 152 can both maintain a circumferential gap with the screw rod.

[0083] A telescopic spring 164 is arranged between the head end support pad 161, the middle support pad 162, and the tail end support pad 163, and the two ends of the telescopic spring 164 are fixedly connected to the corresponding support pads. When the extrusion push block 122 moves forward and backward to approach or move away from the liquid inlet and outlet 1111, it drives the tail end support pad 163 to compress or relax the telescopic spring 164, thereby driving the middle support pad 162 to move forward and backward accordingly. In this process, due to the elastic force setting of the telescopic spring 164 and the structural limitation of the telescopic sleeve assembly 150, the middle support pad 162 and the tail end support pad 163 always support the telescopic sleeve assembly 150, thereby supporting the stirring blade assembly 140, and maintaining the stability of the entire mechanism.

[0084] When the 3D printing extrusion mechanism 100 based on water-based slurry in the embodiment of the present application is used, it is necessary to reversely load the water-based slurry into the extrusion barrel 110. Specifically, first, the operating power member 170 drives the extrusion screw 120, so that the extrusion push block 122 moves in a direction away from the liquid inlet and outlet 1111 under the joint action of the extrusion screw 120 and the axial limiting structure, until it is close to the closed end of the extrusion barrel 110, and sufficient packing space is reserved in the extrusion barrel 110. At this time, the telescopic springs 164 between the support pads are in a slightly compressed or freely extended state, the middle support pad 162 is supported in the sleeve 153 of the inter-leaf sleeve assembly 151 near the closed end, and the tail end support pad 163 is supported in the sleeve 153 of the blade tail sleeve assembly 152 near the closed end. Under the support and driving action of the telescopic support assembly 160, the telescopic sleeve assembly 150 is in an extended state, and the anti-slip limit block 144 is used to make the stirring blades spaced apart. Secondly, the prepared water-based slurry is loaded into a syringe of a suitable type of glue dispenser, and the syringe of the glue dispenser is connected to the air pump so that the discharge port of the syringe of the glue dispenser is aligned with the liquid inlet and outlet 1111 of the extrusion barrel 110. Finally, the air pump is turned on to slowly and evenly load the water-based slurry in the syringe of the glue dispenser into the extrusion barrel 110 until the extrusion barrel 110 is filled.

[0085] After the water-based slurry is loaded, the extrusion work can be carried out. Specifically, the operating power member 170 drives the extrusion screw 120, so that the extrusion push block 122 moves in the direction close to the liquid inlet and outlet 1111 under the joint action of the extrusion screw 120 and the axial limiting structure. In this process, since the stirring blades of the stirring blade assembly 140 are distributed at intervals, and are slidably connected to the telescopic sleeve assembly 150, and are rotatably engaged with the stirring head 130, and the stirring directions of adjacent stirring blades are opposite, the water-based slurry is subjected to the force of the extrusion push block 122, driving the stirring blades to rotate freely. The stirring blades stir the water-based slurry to evenly distribute the solid and liquid phases and avoid liquid phase migration. The evenly stirred water-based slurry is extruded from the liquid inlet and outlet 1111 under the thrust of the extrusion push block 122.

[0086] As the extrusion push block 122 moves toward the direction of the liquid inlet and outlet 1111, the extrusion push block 122 contacts the tail end support pad 163, and the tail end support pad 163 compresses the telescopic spring 164 connected thereto, and the telescopic spring 164 drives the middle support pad 162 connected thereto to move, and so on, each telescopic spring 164 is compressed at the same time, and then moves toward the liquid inlet. At the same time, the extrusion push block 122 also abuts against the sleeve 153 supported by the tail end support pad 163 in the blade tail sleeve assembly 152, and the sleeve 153 also moves toward the liquid inlet and outlet 1111 under the action of the extrusion push block 122. Further, when the compression spring is further compressed, the tail end support pad 163 and the middle support pad 162 abut against the sleeve 153 of the next level close to the extrusion push block 122, pushing the corresponding sleeve assembly to gradually retract toward the liquid inlet and outlet 1111. During this process, the filling space in the extrusion barrel 110 gradually decreases, and adjacent stirring blades gradually approach each other, but the adjacent stirring blades always maintain free rotation in the opposite direction of stirring, and the water-based slurry is continuously stirred, and the solid and liquid phases are evenly distributed until the water-based slurry is completely extruded, thereby avoiding liquid phase migration during the extrusion process.

[0087] The extrusion screw 120 in the embodiment of the present application provides power for the extrusion push block 122. A stirring blade assembly 140 is installed between the stirring head 130 and the extrusion push block 122, and adjacent stirring blades are rotatably connected to the telescopic sleeve assembly 150, which can stir the water-based slurry in different stirring directions, so that the liquid phase distribution is more uniform, and the liquid phase migration phenomenon is effectively avoided. The telescopic support assembly 160 supports the telescopic sleeve assembly 150, and then provides support for the stirring blade assembly 140, ensuring that a gap is retained between the stirring blade assembly 140 and the screw, and free rotation is prevented from interference. The telescopic sleeve assembly 150 can perform telescopic movement during use, so that the stirring blades can adapt to the changes in the filling space of the extrusion barrel 110 and move away from or close to each other to form a stable stirring effect.

[0088] In one feasible embodiment, the extrusion barrel 110 includes a barrel 111 and an end cover 112, one end of the barrel 111 is connected to the end cover 112 to form a closed end, and the other end of the barrel 111 is configured as a truncated cone structure that closes away from the closed end, and a preset opening at the small end of the truncated cone structure forms a liquid inlet and outlet 1111.

[0089] In order to facilitate the connection of the liquid inlet and outlet 1111 to the pipeline or the syringe of the dispensing machine, the small end opening of the truncated cone structure of the extrusion barrel 110 is extended outward to set a section of equal diameter extension tube, and the port of the extension tube can be provided with a quick connector.

[0090] It can be understood that when the stirring head 130 is arranged near the small end of the truncated cone-shaped structure, in order to facilitate the stirring blade assembly 140 to be able to be folded close to the stirring head 130 in the contracted state, the outer diameter of the stirring blades in the stirring blade assembly 140 gradually increases from the front end to the rear end, thereby preventing the stirring blade assembly 140 from interfering with the inner wall surface of the extrusion barrel 110.

[0091] In a feasible embodiment, the power component 170 includes a motor 171, the output end of the motor 171 is fixedly connected to the output seat 172, one end of the extrusion screw 120 extending out of the extrusion barrel 110 is fixedly connected to the screw seat 121, and a feedback housing 176 is arranged on the periphery of the output seat 172 and the screw seat 121.

[0092] The output seat 172 and the screw seat 121 have their end faces close to each other respectively provided with extended edges, the extended edges of the output seat 172 and the screw seat 121 are arranged in a sleeve arrangement, and a torsion spring 173 is installed between the extended edges of the output seat 172 and the screw seat 121.

[0093] An encoder grid is arranged on the periphery of the output seat 172 , an encoder light source 174 is arranged on the periphery of the screw seat 121 , a photosensitive element is arranged on the feedback housing 176 , and an output end of the photosensitive element is electrically connected to a control end of the power member 170 .

[0094] The motor 171 may be a stepper motor. The feedback housing 176 may surround the outer periphery of the output seat 172 and the screw seat 121 and be arranged in a structure connected by buckled bolts, so as to protect the components at the connection between the two and provide an installation position for the photosensitive element.

[0095] The outwardly extending edge of the output seat 172 is located on the inner side of the outwardly extending edge of the screw seat 121, and an annular space is formed between the two outwardly extending edges. The torsion spring 173 is sleeved in the annular space, and one end of the torsion spring 173 is connected to the inner side wall of the outwardly extending edge of the output seat 172, and the other end of the torsion spring 173 is connected to the outer side wall of the outwardly extending edge of the screw seat 121.

[0096] The encoder light source 174, the encoder grid 175 and the photosensitive element constitute a photoelectric encoder. The encoder grid 175 is installed on the outer wall of the extended edge of the output seat 172, the encoder light source 174 is installed on the outer periphery of the screw seat 121, and the photosensitive element is installed on the feedback housing 176 on the side of the encoder grid 175 away from the encoder light source 174.

[0097] During operation, the motor 171 is started, and the output seat 172 rotates along with the output shaft of the motor 171 . However, due to the existence of the torsion spring 173 , the screw seat 121 does not rotate immediately until the maximum resistance torque brought by the water-based slurry in the extrusion barrel 110 is reached, and the screw seat 121 then drives the screw to rotate.

[0098] Since water-based slurries in different states have different viscosities and extrudability, the angles that the torsion spring 173 needs to rotate under different states of the water-based slurry are also different. The output seat 172 has an integrated encoder grid, and the screw seat 121 is equipped with an encoder light source 174. In this way, the encoder light source 174 continuously detects the angular displacement of the encoder grid as the torsion spring 173 rotates, and the current state of the water-based slurry can be fed back by the photosensitive element and transmitted to the control end of the motor 171 in real time, thereby adjusting the rotation speed of the motor 171 to control the extrusion speed to adapt to the current state of the water-based slurry.

[0099] In a feasible embodiment, a retaining spring gasket 131 surrounding the central blind hole is arranged between the stirring head 130 and the head end support pad 161, and the outer periphery of the retaining spring gasket 131 extends out of the outer periphery of the end face of the stirring head 130, and an annular retaining groove matching the retaining spring gasket 131 is arranged near the central hole 143 of the stirring blade of the stirring head 130.

[0100] The outer periphery of the spring washer 131 is rotatably connected to the annular groove. In this way, the spring washer 131 is not only rotatably connected to the first stirring blade 141 at the front end, but also can limit the axial position of the head end support pad 161, thereby limiting the axial displacement of the extrusion screw 120.

[0101] In an achievable embodiment, in the inter-blade sleeve assembly 151, the sleeves 153 on both sides are symmetrically sleeved outwardly layer by layer on the sleeve 153 in the middle, and adjacent sleeves 153 are mutually limited by circumferentially extending annular limiting edges 154. At least one of the two annular limiting edges 154 provided on the sleeve 153 in the middle is detachably connected to the corresponding sleeve 153.

[0102] Taking five sleeves 153 connected from the front end to the rear end as an example, the third sleeve 153 in the middle is located in the innermost layer, the second and fourth sleeves 153 are located in the middle layer, and the first and fifth sleeves 153 are located in the outermost layer.

[0103] The third sleeve 153 has an annular limiting edge 154 protruding outward at both ends, and the annular limiting edge 154 at at least one end can be connected to the outer wall surface of the sleeve 153 by means of a threaded connection.

[0104] The fourth sleeve 153 is provided with an inwardly protruding annular limiting edge 154 at one end close to the third sleeve 153, which cooperates with the annular limiting edge 154 of the third sleeve 153. The fourth sleeve 153 is provided with an outwardly protruding annular limiting edge 154 at one end away from the third sleeve 153.

[0105] An end of the fifth sleeve 153 close to the fourth sleeve 153 is provided with an inwardly protruding annular limiting edge 154, which cooperates with the annular limiting edge 154 of the fourth sleeve 153. An end of the fifth sleeve 153 away from the fourth sleeve 153 is provided with an outwardly protruding annular limiting edge 154, which is used to cooperate with the anti-dropping limiting block 144 of the center hole 143.

[0106] The second and first sleeves 153 are symmetrically arranged with respect to the fourth and fifth sleeves 153 , respectively.

[0107] The anti-dropout limit block 144 near the rear end of the center hole 143 can be integrally arranged with the center hole 143 , and the anti-dropout limit block 144 near the front end of the center hole 143 can be connected in the center hole 143 by threads.

[0108] When installing the inter-blade sleeve assembly 151 and the blade tail sleeve assembly 152, the second and first sleeves 153 can be installed layer by layer on the third sleeve 153, and then the fourth and fifth sleeves 153 can be installed layer by layer, and finally the detachable annular limit edge 154 on the third sleeve 153 near the fourth sleeve 153 can be installed.

[0109] The sleeve assembly is inserted into the front end of the center hole 143 of the previous stirring blade and is restricted by the anti-slip limit block 144 at the rear end. After the rear end of the sleeve assembly is inserted into the stirring blade of the next stage, the anti-slip limit block 144 in the center hole 143 is threadedly installed.

[0110] Considering the length of the extrusion screw 120, when the extrusion barrel 110 is installed as a whole, it can be installed from right to left in sequence until the stirring head 130 is installed, and then the whole is installed in the barrel 111 of the extrusion barrel 110, and then the end cover 112 is installed. Specifically, the stirring blade at the rear end can be installed in the order of the extrusion push block 122, the rear end support pad 163, the telescopic spring 164 at the rear end, the stirring blade at the rear end, and the blade tail sleeve assembly 152. Then, the middle stirring blades are installed in the order of the adjacent middle support pad 162, the adjacent telescopic spring 164, the adjacent stirring blade, the inter-leaf sleeve assembly 151, and the detachable anti-slip limit block 144 on the front side of the center hole 143 of the rear end stirring blade. Finally, install the front end stirring blade in the order of the front end middle support pad 162, the front end telescopic spring 164, the front end stirring blade, the front end inter-blade sleeve assembly 151, the front side detachable anti-slip limit block 144 of the second-stage stirring blade center hole 143, the head end support pad 161, the following retaining ring gasket 131, and the stirring head 130.

[0111] In a feasible embodiment, an intermediate support limit block is provided at the port of the sleeve 153 of the inter-blade sleeve assembly 151 corresponding to the intermediate support pad 162 to prevent the intermediate support pad 162 from falling out, a tail end support limit block is provided at the port of the sleeve 153 of the tail end support pad 163 of the blade tail sleeve assembly 152 corresponding to the tail end support pad 163 to prevent the tail end support pad 163 from falling out, and a sliding limit block for limiting the displacement of the tail end support pad 163 is provided at the preset position of the slide groove 1212.

[0112] The middle support stopper and the tail support stopper can be fixed at the port inside the sleeve 153 by threaded connection. The sliding stopper can be integrally arranged with the extrusion screw 120.

[0113] In this way, the support stopper can prevent the support pad from escaping from the telescopic sleeve assembly 150. The sliding stopper can limit the telescopic length of the telescopic spring 164 to prevent the support pads from being displaced excessively.

[0114] In a feasible embodiment, a slideway is provided on one of the inner wall surface of the extrusion barrel 110 and the outer wall surface of the extrusion push block 122, and a slide bar is provided on the other of the inner wall surface of the extrusion barrel 110 and the outer wall surface of the extrusion push block 122, and the slideway and the slide bar are slidably matched.

[0115] The slideway and the slide bar both extend axially along the extrusion barrel 110 , limiting the extrusion push block 122 to move forward and backward along the axial direction on the extrusion screw rod 120 .

[0116] The following will be combined Figure 11-13 The 3D printing device 200 based on water-based slurry provided in an embodiment of the present application is described.

[0117] The embodiment of the present application provides a water-based slurry-based 3D printing device 200 , including the above-mentioned water-based slurry-based 3D printing extrusion mechanism 100 .

[0118] In this way, the 3D printing device 200 based on water-based slurry has the same beneficial effects as the above-mentioned 3D printing extrusion mechanism 100 based on water-based slurry, and can continuously stir the water-based slurry during the extrusion process, promote uniform distribution of the liquid phase, and effectively solve the liquid phase migration phenomenon during the extrusion process of the water-based slurry.

[0119] In one feasible embodiment, the water-based slurry-based 3D printing device 200 also includes a pressurizing mechanism 210, which includes a thick tube solenoid valve 211, a first feed thick tube 2111, a first pressurizing barrel 212, a second feed thick tube 2112, a second pressurizing barrel 213, a first feed thin tube 2171, a second feed thin tube 2172 and a thin tube solenoid valve 217.

[0120] The liquid inlet and outlet 1111 of the extrusion barrel 110 of the 3D printing extrusion mechanism 100 based on water-based slurry is connected to the inlet of the thick tube solenoid valve 211, the first outlet of the thick tube solenoid valve 211 is connected to the first pressurizing barrel 212 through the first feed thick tube 2111, and the second outlet of the thick tube solenoid valve 211 is connected to the second pressurizing barrel 213 through the second feed thick tube 2112. The outlet of the first pressurizing barrel 212 is connected to the first inlet of the thin tube solenoid valve 217 through the first feed thin tube 2171, the outlet of the second pressurizing barrel 213 is connected to the second inlet of the thin tube solenoid valve 217 through the second feed thin tube 2172, and the outlet of the thin tube solenoid valve 217 is connected to the extruder head 225.

[0121] Among them, the first pressurizing barrel 212 and the second pressurizing barrel 213 can be arranged symmetrically, and a pressurizing push block 214 connected to the pressurizing screw 216 is arranged inside both, and an axial limiting mechanism is arranged between the pressurizing push block 214 and the inner wall surface of the pressurizing barrel to limit the pressurizing push block 214 to move axially along the pressurizing barrel during the rotation of the pressurizing screw 216.

[0122] The pressurizing screw 216 of the first pressurizing barrel 212 and the second pressurizing barrel 213 can share a double-axis screw stepper motor 215. The shared double-axis screw stepper motor 215 drives the pressurizing screw 216 on one side to rotate forward, so that the pressurizing push block 214 vacates the filler space for the feeding operation, and the pressurizing screw 216 on the other side rotates reversely, so that the pressurizing push block 214 extrude the water-based slurry, and then the two pressurizing screws 216 can work alternately.

[0123] When in use, the water-based slurry is transferred from the liquid inlet and outlet 1111 of the extrusion barrel 110 through the thick tube to the thick tube solenoid valve 211. The thick tube solenoid valve 211 opens the passage of the first outlet, and the double-axis screw stepper motor 215 rotates to empty the first pressurizing barrel 212 corresponding to the first outlet. The water-based slurry can then pass through the first feed thick tube 2111 and enter the corresponding first pressurizing barrel 212. When the first pressurizing barrel 212 is filled with the water-based slurry, the thick tube solenoid valve 211 disconnects the passage of the first outlet and opens the passage of the second outlet. At the same time, the double-axis screw stepper motor 215 reverses, and the pressurizing push block 214 in the first pressurizing barrel 212 performs the action of extruding the water-based slurry. At this time, the second pressurizing barrel 213 on the other side repeats the previous feeding filling step to achieve reciprocating non-continuous extrusion. When entering the extruder head 225, the capillary solenoid valve 217 will also be opened and closed according to the different working states of the pressure push blocks 214 on both sides, so as to realize alternating extrusion and minimize the influence of liquid phase migration on printing.

[0124] In an achievable implementation, the water-based slurry-based 3D printing device 200 further includes an extruder head motion mechanism 220, which includes a gantry frame 221, an extruder head 225, a Y-axis motion member, an X-axis motion member, and a Z-axis motion member.

[0125] The gantry frame 221 includes a base 222 , a crossbeam 223 and two vertical beams 224 . The two vertical beams 224 are arranged on the base 222 opposite to each other, and the crossbeam 223 is connected to the upper parts of the two vertical beams 224 .

[0126] The feed end of the extruder head 225 is connected to the outlet of the capillary solenoid valve 217 through the discharge capillary 2173. The extruder head 225 is arranged on the Y-axis sliding member 226 at the crossbeam 223, and the Y-axis sliding member 226 is connected to the Y-axis moving member, and the Y-axis moving member is controlled to drive the extruder head 225 to move along the extension direction of the crossbeam 223.

[0127] A Z-axis sliding plate 228 is disposed between the two vertical beams 224 . The Z-axis sliding plate 228 extends in a horizontal direction and is connected to a Z-axis moving member. The Z-axis moving member is controlled to drive the Z-axis sliding plate 228 to move in the extending direction of the vertical beams 224 .

[0128] An X-axis sliding plate 227 is arranged above the Z-axis sliding plate 228. The X-axis sliding plate 227 extends in the horizontal direction and is connected to the X-axis moving part. The X-axis moving part is controlled to drive the X-axis sliding plate 227 to move in the X-axis direction. The X-axis direction is perpendicular to the extension direction of the horizontal beam 223 and the vertical beam 224.

[0129] The Y-axis sliding member 226 may be a slider slidably connected to the crossbeam 223. The Y-axis moving member may be a cylinder or a linear screw motor, which drives the slider to drive the extrusion head 225 to move along the extension direction of the crossbeam 223.

[0130] The two ends of the Z-axis sliding plate 228 can be slidably connected in the sliding grooves preset in the two vertical beams 224. The Z-axis moving parts are unilaterally or symmetrically arranged at the two vertical beams 224, and can be cylinders or linear screw motors to drive the Z-axis sliding plate 228 to move along the extension direction of the vertical beams 224.

[0131] The bottom of the X-axis sliding plate 227 can be slidably connected in a preset sliding groove on the top of the Z-axis sliding plate 228. The X-axis moving part can be a cylinder or a linear screw motor to drive the X-axis sliding plate 227 to move along the X-axis direction.

[0132] In this way, the extrusion head 225 has only one degree of freedom in the Y-axis direction, and the X-axis and Z-axis degrees of freedom are completed by the X-axis moving part and the Z-axis moving part. The liquid phase migration phenomenon can be reduced by shortening the distance between the extrusion head 225 and the pressurized barrel.

[0133] It should be noted that, unless otherwise clearly specified and limited, in the description of this application, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, or it can be an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.

[0134] The orientations or positional relationships indicated by terms such as “upper”, “lower”, “front”, “back”, “vertical”, “horizontal”, “top”, “bottom”, “inside” and “outside” are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of describing the present application and simplifying the description. They do not indicate or imply 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 understood as a limitation on the present application.

[0135] The term "plurality" means two or more than two, unless expressly specified otherwise.

[0136] The terms "first", "second", "third", "fourth", etc. (if any) are used to distinguish similar objects and are not necessarily used to describe a particular order or precedence. It should be understood that the terms used in this way are interchangeable where appropriate, so that the embodiments of the present application described herein can include sequential implementations other than those illustrated or described herein.

[0137] The terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion. For example, a process, method, system, product, or apparatus that comprises a series of steps or elements is not necessarily limited to those steps or elements explicitly listed but may include other steps or elements not explicitly listed or inherent to such process, method, product, or apparatus.

[0138] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A 3D printing extrusion mechanism based on water-based slurry, characterized in that: It includes an extrusion barrel, an extrusion screw rod, an extrusion push block, a stirring head, a stirring blade assembly, a telescopic sleeve assembly and a telescopic support assembly; One end of the extrusion barrel is provided with a liquid inlet and outlet, and the other end of the extrusion barrel is closed; The extrusion screw rod axially passes through the closed end of the extrusion barrel into the extrusion barrel, one end of the extrusion screw rod extending out of the closed end of the extrusion barrel is connected to the power member, and one end of the extrusion screw rod located in the extrusion barrel is arranged near the liquid inlet and outlet and connected to the stirring head; The extrusion push block is threadedly connected to the extrusion screw rod, and the outer wall surface of the extrusion push block is slidably connected to the inner wall surface of the extrusion barrel, and an axial limiting structure is arranged between the extrusion barrel and the extrusion push block; The stirring blade assembly is arranged between the stirring head and the extrusion push block, and the stirring blade assembly includes a first stirring blade and a second stirring blade arranged alternately, the stirring directions of the first stirring blade and the second stirring blade are opposite, and the first stirring blade and the second stirring blade are both provided with a central hole with a gap with the extrusion screw rod, and the stirring blade close to one end of the stirring head is rotatably engaged with the outer periphery of the stirring head; The telescopic sleeve assembly comprises an inter-blade sleeve assembly and a blade tail sleeve assembly of the same structure, and the inter-blade sleeve assembly comprises an odd number of sleeves, and the odd number of sleeves are mounted outwards layer by layer from both sides with the sleeve located in the middle as the inner layer; An inter-blade sleeve assembly is installed between the adjacent first stirring blades and the second stirring blades, the sleeves at both ends of the inter-blade sleeve assembly are respectively slidably connected to the center holes of the adjacent stirring blades, and the ports of the corresponding center holes are provided with anti-slip limit blocks to prevent the inter-blade sleeve assembly from slipping off; The blade tail sleeve assembly is installed between the stirring blade close to the extrusion push block and the extrusion push block, the sleeve of the blade tail sleeve assembly close to the stirring blade is slidably connected with the center hole of the corresponding stirring blade, and an anti-slip limit block is arranged at the port of the corresponding center hole to prevent the blade tail sleeve assembly from slipping off, and the sleeve of the blade tail sleeve assembly close to the extrusion push block is used to abut against the extrusion push block; The telescopic support assembly comprises a head end support pad, an intermediate support pad, a tail end support pad and a telescopic spring, and the extrusion screw rod is provided with at least two slide grooves extending along the axial direction; one side of the head end support pad is embedded in the preset central blind hole of the stirring head, and the other side of the head end support pad is embedded in the slide groove at the end of the extrusion screw rod; each of the inter-leaf sleeve assemblies is installed in the sleeve away from the stirring head side of the intermediate support pad, the outer periphery of the intermediate support pad is supported by the inner wall surface corresponding to the sleeve, and the center of the intermediate support pad surrounds the extrusion screw rod and is slidably connected to the slide groove; the tail end support pad is installed in the sleeve away from the stirring head side of the blade tail sleeve assembly, the outer periphery of the tail end support pad is supported by the inner wall surface corresponding to the sleeve, and the end face of the tail end support pad away from the stirring head side is used to abut against the extrusion push block, and the center of the tail end support pad surrounds the extrusion screw rod and is slidably connected to the slide groove; A telescopic spring is connected between the head end support pad and the middle support pad, between adjacent middle support pads, and between the middle support pad and the tail end support pad.

2. The 3D printing extrusion mechanism based on water-based slurry according to claim 1, characterized in that: The extrusion barrel includes a barrel and an end cover, one end of the barrel is connected to the end cover to form a closed end, and the other end of the barrel is configured as a truncated cone structure that closes away from the closed end, and a preset opening at the small end of the truncated cone structure forms the liquid inlet and outlet.

3. The 3D printing extrusion mechanism based on water-based slurry according to claim 1, characterized in that: The power member comprises a motor, the output end of the motor is fixedly connected to the output seat, one end of the extrusion screw extending out of the extrusion barrel is fixedly connected to the screw seat, and a feedback housing is arranged on the periphery of the output seat and the screw seat; The end surfaces of the output seat and the screw seat that are close to each other are respectively provided with overhanging edges, the overhanging edges of the output seat and the overhanging edges of the screw seat are arranged in a sleeve arrangement, and a torsion spring is installed between the corresponding overhanging edges; An encoder grid is arranged at the periphery of the output seat, an encoder light source is arranged at the periphery of the screw seat, a photosensitive element is arranged on the feedback housing, and an output end of the photosensitive element is electrically connected to a control end of the power part.

4. The 3D printing extrusion mechanism based on water-based slurry according to any one of claims 1 to 3, characterized in that: A retaining spring gasket surrounding the central blind hole is arranged between the stirring head and the head end support pad, the outer periphery of the retaining spring gasket extends out of the outer periphery of the end face of the stirring head, and an annular retaining groove matching the retaining spring gasket is arranged near the central hole of the stirring blade of the stirring head.

5. The 3D printing extrusion mechanism based on water-based slurry according to any one of claims 1 to 3, characterized in that: In the inter-blade sleeve assembly, the sleeves on both sides are symmetrically mounted outwardly layer by layer on the sleeve located in the middle, and adjacent sleeves are limited to each other by circumferentially extending annular limit edges; at least one of the two annular limit edges arranged on the sleeve located in the middle is detachably connected to the corresponding sleeve.

6. The 3D printing extrusion mechanism based on water-based slurry according to any one of claims 1 to 3, characterized in that: An intermediate support limit block is provided at the port of the sleeve of the intermediate support pad corresponding to the inter-blade sleeve assembly to prevent the intermediate support pad from falling out; a tail end support limit block is provided at the port of the sleeve of the tail end support pad corresponding to the tail end support pad of the blade tail sleeve assembly to prevent the tail end support pad from falling out; a sliding limit block is provided at the preset position of the slide groove to limit the displacement of the tail end support pad.

7. The 3D printing extrusion mechanism based on water-based slurry according to any one of claims 1 to 3, characterized in that: A slideway is provided on one of the inner wall surface of the extrusion barrel and the outer wall surface of the extrusion push block, and a slide bar is provided on the other of the inner wall surface of the extrusion barrel and the outer wall surface of the extrusion push block, and the slideway is slidably matched with the slide bar.

8. A 3D printing device based on water-based slurry, characterized in that: It comprises a 3D printing extrusion mechanism based on water-based slurry as described in any one of claims 1 to 7.

9. The 3D printing device based on water-based slurry according to claim 8, characterized in that: It also includes a pressurizing mechanism, which includes a thick tube solenoid valve, a first thick feeding tube, a first pressurizing barrel, a second thick feeding tube, a second pressurizing barrel, a first thin feeding tube, a second thin feeding tube and a thin tube solenoid valve; The liquid inlet and outlet of the extrusion barrel of the water-based slurry-based 3D printing extrusion mechanism are connected to the inlet of the thick tube solenoid valve, the first outlet of the thick tube solenoid valve is connected to the first pressurized barrel through the first feed thick tube, and the second outlet of the thick tube solenoid valve is connected to the second pressurized barrel through the second feed thick tube; the outlet of the first pressurized barrel is connected to the first inlet of the capillary solenoid valve through the first feed capillary tube, the outlet of the second pressurized barrel is connected to the second inlet of the capillary solenoid valve through the second feed capillary tube, and the outlet of the capillary solenoid valve is connected to the extrusion head.

10. The 3D printing device based on water-based slurry according to claim 8 or 9, characterized in that: It also includes an extrusion head motion mechanism, which includes a gantry frame, an extrusion head, a Y-axis motion part, an X-axis motion part, and a Z-axis motion part; The gantry frame comprises a base, a crossbeam and two vertical beams, the two vertical beams are arranged oppositely on the base, and the crossbeam is connected to the upper parts of the two vertical beams; The feed end of the extruder head is connected to the outlet of the capillary solenoid valve through a discharge capillary tube; the extruder head is arranged on a Y-axis sliding member at the crossbeam, the Y-axis sliding member is connected to the Y-axis moving member, and the Y-axis moving member is controlled to drive the extruder head to move along the extension direction of the crossbeam; A Z-axis sliding plate is arranged between the two vertical beams, the Z-axis sliding plate extends in a horizontal direction and is connected to a Z-axis moving part, and the Z-axis moving part is controlled to drive the Z-axis sliding plate to move in the extending direction of the vertical beams; An X-axis sliding plate is arranged above the Z-axis sliding plate, and the X-axis sliding plate extends in a horizontal direction and is connected to an X-axis moving part, and the X-axis moving part is controlled to drive the X-axis sliding plate to move in an X-axis direction, and the X-axis direction is perpendicular to the extension direction of the horizontal beam and the vertical beam.

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