Extrusion nozzle for 3D printing concrete interlayer interlocking forming

Abstract

The invention relates to the technical field of concrete printing, and discloses an extrusion nozzle for 3D printing concrete interlayer interlocking forming, which comprises a path synchronizing mechanism, a concrete pipeline, a support frame, a building width adjusting mechanism and a width adjusting mechanism. The concrete pipeline is communicated with the first edge spray head, the second edge spray head and the middle swing spray head. The building width adjusting mechanism synchronously adjusts the distance between the nozzles on the two sides through an opposite-pulling lead screw. The path synchronizing mechanism converts printing advancing displacement into rotation input through a land wheel assembly, a balance weight transmission box and a polygonal transmission rod. The width adjusting mechanism drives the middle swing spray head to reciprocate through a screw rod, a second thread driving block, a reciprocating driving assembly, a dynamic meshing block and a spring reversing structure, and drives the middle sliding block to synchronously translate through a sleeve block during width adjustment so as to synchronously form an edge material belt and an interlayer interlocking material belt. The nozzle gives consideration to the interlayer interlocking forming capacity and the mechanical transmission reliability under the working conditions of different wall widths.

Description

Technical Field

[0001] This invention relates to the field of concrete printing technology, specifically to an extrusion nozzle for 3D printing interlocking concrete layers. Background Technology

[0002] With the development of 3D printing technology in construction, the layer-by-layer stacking of concrete materials to form building structures such as walls has become an important method in industrialized construction. Existing concrete 3D printing devices typically use a nozzle to continuously extrude material along a predetermined path to form wall edges or filling structures. However, in existing technologies, it is often difficult to concentrate the straight-line material extrusion at the edges and the oscillating material extrusion at the center within the same nozzle body. This results in the material on both sides of the edges and the interlocking material in the center often not being extruded and formed synchronously in a single printing process, thus requiring additional reinforcement processes or additional forming steps. This not only increases construction complexity but also hinders the consistency of interlayer forming. Therefore, how to provide an extrusion nozzle that can concentrate the straight-line material extrusion at the edges and the oscillating material extrusion at the center within the same nozzle body and simultaneously complete the extrusion forming of the material on both sides of the edges and the interlocking material in the center in a single printing process has become a technical problem urgently needing to be solved by those skilled in the art. Summary of the Invention

[0003] This application provides an extrusion nozzle for 3D printing concrete interlayer interlocking forming. The main purpose is to achieve the convergence of straight material output from the sides and oscillating material output from the center within the same nozzle body through synchronous force taking along the path, synchronous width adjustment of the sides, and adaptive reciprocating cooperation of the oscillating nozzle in the center, and to simultaneously complete the extrusion forming of the material on both sides and the interlocking material in the center during a single printing process.

[0004] To achieve the above objectives, this application provides an extrusion nozzle for interlocking interlayer forming of 3D printed concrete, including a path synchronization mechanism, a concrete pipeline, a support frame, a building width adjustment mechanism, and a reinforcing rib adaptive width adjustment mechanism. The concrete pipeline is connected to the first side nozzle, the second side nozzle, and the middle swing nozzle, respectively. The support frame is movably provided with a first side slider, a middle slider and a second side slider. The first side nozzle, the second side nozzle and the middle swing nozzle are respectively disposed at the bottom end of the corresponding slider. The middle slider is located between the first side slider and the second side slider. The building width adjustment mechanism is located on one side of the support frame and includes a pull rod with reverse threads on both sides. The first side slider and the second side slider are respectively screwed to the reverse threads on both sides of the pull rod through the first thread drive block and the third thread drive block, so that they move closer or further away from each other synchronously when the pull rod rotates, thereby changing the distance between the first side nozzle and the second side nozzle. The path synchronization mechanism includes a ground wheel assembly, a counterweight transmission box, a polygonal transmission rod, and a reciprocating drive assembly, used to convert the printing travel displacement of the extrusion nozzle along the construction path into rotational input; the reinforcing rib adaptive width adjustment mechanism includes a second housing and a screw, the central slider is screwed onto the screw via a second threaded drive block, and the central slider is also provided with a horizontally movable locking block in the building width adjustment mechanism, so that when the building width is adjusted, the central slider moves synchronously with the position changes of the first side slider and the second side slider and remains in the updated central working range; the reciprocating drive assembly is connected to the polygonal transmission rod and drives the screw to rotate forward or backward through an active bevel gear, a first direction bevel gear, a second direction bevel gear, a dynamic meshing block, and a spring reversing structure, so as to drive the central slider to move back and forth, thereby causing the central oscillating nozzle to output interlayer interlocking material strip between the first side nozzle and the second side nozzle.

[0005] In one feasible implementation, the path synchronization mechanism includes a ground wheel assembly, a counterweight transmission box, a polygonal transmission rod, and a reciprocating drive assembly. The ground wheel assembly has two rotating wheels connected by a power shaft. The power shaft is connected to the counterweight transmission box. The output end of the counterweight transmission box is connected to the polygonal transmission rod, and the polygonal transmission rod is connected to the reciprocating drive assembly.

[0006] In one feasible implementation, a support frame is fitted on the outer wall of the concrete pipe, the polygonal transmission rod rotatably passes through the support frame via a support bearing sleeve, the reciprocating drive assembly is fixedly disposed on the side of the support frame, and the reciprocating drive assembly includes a drive assembly input shaft fitted on the polygonal transmission rod.

[0007] In one feasible implementation, the support frame is provided with a first side slider, a middle slider, and a second side slider. The first side slider and the second side slider are located at opposite ends of the support frame and can move closer to or further away from each other. The middle slider is located between the first side slider and the second side slider. The first side nozzle is located at the bottom end of the first side slider, the second side nozzle is located at the bottom end of the second side slider, and the middle swing nozzle is located at the bottom end of the middle slider.

[0008] In one feasible embodiment, the building width adjustment mechanism includes a first housing, a pull rod, and an adjustment block. The pull rod is disposed within a support frame and has reverse threads on both sides. The adjustment block is disposed at the end of the pull rod. A first threaded drive block is provided on the side of the first side slider, and a third threaded drive block is provided on the side of the second side slider. The first threaded drive block and the third threaded drive block are respectively screwed onto the reverse threads on both sides of the pull rod, so that when the pull rod rotates, it drives the first side slider and the second side slider to move closer or further away from each other synchronously.

[0009] In one feasible implementation, the reinforcing rib adaptive width adjustment mechanism includes a second housing and a screw, the screw being located inside the second housing; a second threaded drive block is provided at the end of the central slider, the second threaded drive block being screwed onto the screw; a sleeve block is provided at the end of the central slider away from the second threaded drive block, the sleeve block being horizontally movable and engaged within the building width adjustment mechanism, and being spaced apart from the pull rod, so that the central slider moves synchronously with the position changes of the first side slider and the second side slider during building width adjustment.

[0010] In one feasible implementation, the reciprocating drive assembly further includes a driving bevel gear, a first directional bevel gear, and a second directional bevel gear. The driving bevel gear is connected to the input shaft of the drive assembly via a reversing transmission mechanism. The first directional bevel gear and the second directional bevel gear are coaxially opposite each other, and the outer walls of both the first directional bevel gear and the second directional bevel gear mesh with the driving bevel gear. The first directional bevel gear and the second directional bevel gear are both provided with channels for the axial movement of the screw. A dynamic meshing block is fixedly sleeved on the outer wall of the screw. The dynamic meshing block can switch to mesh with the first directional bevel gear or the second directional bevel gear as the screw moves axially, so that the screw rotates forward or in reverse.

[0011] In one feasible implementation, a first spring and a second spring are respectively provided on the sidewalls of the first threaded drive block and the third threaded drive block that are close to each other. When the second threaded drive block moves with the middle slider to the end of its stroke near the first side slider or the second side slider, it can contact and compress the first spring or the second spring, so as to push the screw to move axially by the thrust of the spring, thereby driving the dynamic meshing block to switch the meshing position.

[0012] In one feasible embodiment, a positioning component is provided on the outer wall of the second housing. The positioning component includes an elastic sheet and a ball seat disposed on the elastic telescopic end of the elastic sheet. Two adjacent annular grooves are provided on the screw corresponding to the position of the ball seat. The ball seat can be inserted into either annular groove as the screw moves axially to position the axial position of the screw.

[0013] This application provides an extrusion nozzle for 3D printing concrete interlayer interlocking forming. It achieves synchronous width adjustment of the two side nozzles through a wire-drawing rod, and utilizes a ground wheel assembly, a counterweight transmission box, and a polygonal transmission rod to achieve mechanical force acquisition related to the printing displacement. Through the coordinated action of a screw, a second threaded drive block, a sleeve block, a dynamic engagement block, and a spring-reversing structure, the central oscillating nozzle reciprocates within the updated central working area. This allows for the simultaneous extrusion forming of the material on both sides and the central interlayer interlocking material during a single printing process, balancing adaptability to different wall widths, interlayer interlocking capability, and mechanical transmission reliability. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the overall structure of an extrusion nozzle for interlocking concrete layer forming in 3D printing according to the present invention. Figure 2 This is a schematic diagram of the path synchronization mechanism in an extrusion nozzle for interlocking molding of concrete layers in 3D printing according to the present invention. Figure 3 This is a schematic diagram of the reciprocating drive assembly in an extrusion nozzle for interlocking molding of concrete layers in 3D printing according to the present invention. Figure 4 This is a schematic diagram of the structure of the first side nozzle in an extrusion nozzle for interlocking molding of concrete layers in 3D printing according to the present invention. Figure 5 This is a schematic diagram of the screw in an extrusion nozzle for interlocking molding of concrete layers in 3D printing according to the present invention. Figure 6 This is a schematic diagram of the central slider in an extrusion nozzle for interlocking concrete layer forming in 3D printing according to the present invention. Figure 7 This is a schematic diagram of the structure of the positioning component and screw in an extrusion nozzle for interlocking interlayer forming of 3D printed concrete according to the present invention. Figure 8 This is a schematic diagram of the dynamic interlocking block in an extrusion nozzle for 3D printing of interlocking concrete layers, according to the present invention.

[0015] In the diagram: 100, base; 200, path synchronization mechanism; 300, concrete pipe; 400, support frame; 500, building width adjustment mechanism; 600, reinforcing rib adaptive width adjustment mechanism; 110, edge strip; 120, reinforcing rib; 210, ground wheel assembly; 220, polygonal transmission rod; 230, support sleeve; 240, reciprocating drive assembly; 211, rotating wheel; 212, counterweight transmission box; 213, transmission box output end; 231, support bearing sleeve; 241, drive assembly input shaft; 242, driving bevel gear; 243, first direction bevel gear; 244, second direction bevel gear. 310. First side nozzle; 320. Second side nozzle; 330. Central oscillating nozzle; 410. First side slider; 411. First threaded drive block; 412. First spring; 420. Central slider; 421. Sleeve block; 422. Second threaded drive block; 430. Second side slider; 431. Third threaded drive block; 432. Second spring; 510. First housing; 520. Pull rod; 530. Adjusting block; 610. Second housing; 620. Positioning assembly; 630. Screw; 640. Dynamic engagement block; 621. Elastic sheet; 622. Ball seat; 623. Annular groove. Detailed Implementation

[0016] To better understand the technical solutions provided in the embodiments of this specification, the technical solutions of the embodiments of this specification will be described in detail below with reference to the accompanying drawings and specific embodiments. It should be understood that the embodiments of this specification and the specific features in the embodiments are detailed descriptions of the technical solutions of the embodiments of this specification, rather than limitations on the technical solutions of this specification. In the absence of conflict, the embodiments of this specification and the technical features in the embodiments can be combined with each other.

[0017] In this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, without necessarily requiring or implying any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element. The term "two or more" includes two or more cases.

[0018] It should be noted that the extrusion nozzle described in this embodiment is a functional component installed on a building 3D printing equipment, and the object of protection is the nozzle body and its internal transmission, adjustment, and feeding structures. The supporting foundation, printing object, printed structure, or other external environment shown in the accompanying drawings are for illustrative purposes only, to understand the working scenario of this embodiment, and are not intended to limit the components of the extrusion nozzle in this embodiment. The structures described below in this embodiment primarily focus on the components that constitute the extrusion nozzle body and directly participate in feeding, width adjustment, transmission, and reciprocating motion, thereby clearly defining the boundaries of the protected object and facilitating an accurate understanding of the substantive content of this technical solution.

[0019] like Figures 1 to 8 As shown, this embodiment provides an extrusion nozzle for 3D printing interlocking concrete layers, including a path synchronization mechanism 200, a concrete pipeline 300, a support frame 400, a building width adjustment mechanism 500, and a reinforcing rib adaptive width adjustment mechanism 600. The lower part of the concrete pipeline 300 is connected to a first side nozzle 310, a second side nozzle 320, and a central oscillating nozzle 330. The first side nozzle 310 and the second side nozzle 320 are used to eject side strips 110 extending along the printing direction. The central oscillating nozzle 330 is used to eject an interlocking material strip formed by reciprocating oscillation between the two side strips 110, preferably forming a periodic waveform trajectory. By concentrating the straight edge ejection and the central oscillating ejection within the same nozzle body, the extrusion forming of the two side materials and the central interlocking material above the base 100 can be completed simultaneously in a single printing process, thereby reducing subsequent reinforcement processes and improving the consistency of interlocking formation.

[0020] like Figure 1 , Figure 2 , Figure 4 and Figure 5 As shown, the support frame 400 constitutes the main mounting skeleton of the entire extrusion nozzle. The first side slider 410, the middle slider 420, and the second side slider 430 are movably disposed within the support frame 400. The first side slider 410 and the second side slider 430 are located at opposite ends of the support frame 400, with the middle slider 420 positioned between them. The first side nozzle 310 is fixed to the bottom end of the first side slider 410, the second side nozzle 320 is fixed to the bottom end of the second side slider 430, and the middle swing nozzle 330 is fixed to the bottom end of the middle slider 420. Thus, the three nozzles obtain a unified guiding reference within the same support frame 400. The two side nozzles primarily serve to define the width boundaries, while the middle nozzle primarily serves to form interlayer interlocking trajectories, thereby ensuring the stability of their relative positions and improving the repeatability of the printing trajectory.

[0021] like Figure 1 , Figure 2 and Figure 3 As shown, the concrete pipe 300 is used to supply material to the first side nozzle 310, the second side nozzle 320, and the central oscillating nozzle 330. A valve-plate flow equalization structure can be installed inside the concrete pipe 300 to distribute the incoming concrete flow to the three outlet branches, ensuring a basically balanced supply to the three nozzles during printing. A support sleeve 230 is fitted onto the outer wall of the concrete pipe 300, and a polygonal transmission rod 220 rotatably passes through the support sleeve 230 via a support bearing sleeve 231. That is, the concrete pipe 300 not only performs the material conveying function but also provides a central support interface for the polygonal transmission rod 220, allowing the supply channel and power transmission channel to form a compact spatial arrangement, thereby reducing the overall lateral dimension of the nozzles while improving transmission stability.

[0022] like Figure 2 and Figure 3 As shown, the path synchronization mechanism 200 is used to acquire mechanical power during the movement of the printing equipment and transmit this power to the reciprocating drive chain of the intermediate oscillating nozzle 330. The path synchronization mechanism 200 includes two rotating wheels 211 connected by a power shaft. The power shaft is connected to a counterweight transmission box 212. The upper part of the counterweight transmission box 212 forms a transmission box output end 213, which is connected to a longitudinally arranged polygonal transmission rod 220. When the nozzle moves along the construction path with the printing equipment, the ground wheel assembly 210 forms rolling contact with the travel path, thereby converting the travel displacement into ground wheel rotation input. The counterweight transmission box 212 maintains a stable pressing state between the ground wheel assembly 210 and the contact surface through the counterweight, making it less prone to slippage during the rolling force acquisition process. This allows the polygonal transmission rod 220 to obtain rotational input corresponding to the printing travel process, thereby enabling the subsequent intermediate nozzle oscillation rhythm to establish a stable correlation with the printing displacement.

[0023] like Figure 2 , Figure 3 , Figure 6 and Figure 7As shown, the reciprocating drive assembly 240 is fixedly mounted on the side of the support frame 400 and is connected to the polygonal transmission rod 220. The reciprocating drive assembly 240 includes a drive assembly input shaft 241, a drive bevel gear 242, a first direction bevel gear 243, and a second direction bevel gear 244. The drive assembly input shaft 241 is sleeved on the polygonal transmission rod 220. The drive bevel gear 242 is connected to the drive assembly input shaft 241 via a reversing transmission mechanism. The first direction bevel gear 243 and the second direction bevel gear 244 are coaxially opposite to each other and both mesh with the drive bevel gear 242. The first direction bevel gear 243 and the second direction bevel gear 244 continuously rotate with the drive bevel gear 242, but their rotation directions are opposite to those of the screw 630. Therefore, by selectively establishing a transmission relationship between one of them and the screw 630 at an appropriate time, the forward or reverse movement of the middle slider 420 can be achieved, thereby avoiding frequent reversing using complex electrical control and improving the reliability of mechanical reversing.

[0024] like Figure 4 , Figure 5 and Figure 8 As shown, the building width adjustment mechanism 500 is located on one side of the support frame 400 and is mainly used to synchronously adjust the spacing between the two edge nozzles to adapt to printing requirements of different wall widths or different reinforcing rib spans. The building width adjustment mechanism 500 includes a first housing 510, a pull rod 520, and an adjustment block 530. The pull rod 520 is located inside the support frame 400 and has reverse threads on both sides. A first threaded drive block 411 is provided on the side of the first edge slider 410, and a third threaded drive block 431 is provided on the side of the second edge slider 430. The first threaded drive block 411 and the third threaded drive block 431 are respectively screwed onto the reverse threads on both sides of the pull rod 520. The adjusting block 530 is located at the end of the pull rod 520. When an external tool drives the adjusting block 530 to rotate, the pull rod 520 rotates synchronously. The first thread drive block 411 and the third thread drive block 431, located on opposite threads on both sides, will move towards each other or away from each other, thereby driving the first side slider 410 and the second side slider 430 to adjust their width synchronously. This structure ensures that the adjustment amount of the two side nozzles remains mirror-symmetrical, which helps to keep the central printing area in the middle position between the two side nozzles, thereby improving the printing symmetry after width adjustment.

[0025] like Figure 4 , Figure 6 , Figure 7 and Figure 8As shown, the reinforcing rib adaptive width adjustment mechanism 600 is located on the other side of the support frame 400 and forms a power transmission relationship with the path synchronization mechanism 200. The reinforcing rib adaptive width adjustment mechanism 600 includes a second housing 610, a screw 630, and a dynamic engagement block 640. The screw 630 is located inside the second housing 610, and a second threaded drive block 422 is provided at the end of the middle slider 420. The second threaded drive block 422 is screwed onto the screw 630. When the screw 630 rotates, the second threaded drive block 422 moves linearly along the screw 630 in the axial direction, thereby driving the middle slider 420 and the middle oscillating nozzle 330 to move laterally. Since the displacement of the middle oscillating nozzle 330 is directly converted from the rotational input provided by the path synchronization mechanism 200 to the screw 630 via the reciprocating drive assembly 240, a stable correspondence can be established between the oscillation rhythm of the middle nozzle and the printing travel displacement, thereby facilitating the formation of a layer interlocking trajectory with good repeatability.

[0026] like Figure 4 and Figure 8 As shown, a sleeve block 421 is provided at the end of the central slider 420 away from the second threaded drive block 422. The sleeve block 421 is horizontally moved and engaged within the building width adjustment mechanism 500, and does not contact the pull rod 520. In this embodiment, the sleeve block 421 does not directly participate in the threaded transmission of the pull rod 520, but rather serves as a wide-width following guide structure for the central slider 420. When the first side slider 410 and the second side slider 430 change their spacing under the drive of the building width adjustment mechanism 500, the translational path range of the sleeve block 421 will also change synchronously, so that the central slider 420 is entirely within the updated central working area. Thus, the central oscillating nozzle 330 can still oscillate back and forth around the new central area under different printing widths, thereby improving the adaptability of the extrusion nozzle to different wall width conditions.

[0027] like Figure 6 , Figure 7 and Figure 8As shown, a dynamic engagement block 640 is fixedly sleeved on the outer wall of the screw 630. Both the first-direction bevel gear 243 and the second-direction bevel gear 244 have internal channels for axial movement of the screw 630. The dynamic engagement block 640 switches its engagement relationship with either the first-direction bevel gear 243 or the second-direction bevel gear 244 as the axial position of the screw 630 changes. When the dynamic engagement block 640 engages with the first-direction bevel gear 243, the rotation output by the driving bevel gear 242 is transmitted to the screw 630 via the first-direction bevel gear 243, causing the screw 630 to rotate in the first direction. When the dynamic engagement block 640 switches to engagement with the second-direction bevel gear 244, the screw 630 rotates in the opposite direction. This method of switching engagement positions to achieve forward and reverse rotation allows the middle slider 420 to complete left and right reciprocating motion without changing the drive source, thereby simplifying the drive chain configuration and improving the directness of the transmission switching response.

[0028] like Figure 5 , Figure 6 and Figure 8 As shown, to automatically trigger the screw 630 to reverse direction when the middle slider 420 moves to either end, a first spring 412 and a second spring 432 are respectively provided on the sidewalls of the first threaded drive block 411 and the third threaded drive block 431 that are close to each other. When the middle slider 420 moves towards the first side slider 410 and approaches the end of its stroke, the second threaded drive block 422 gradually contacts and compresses the first spring 412; as the compression increases, the first spring 412 applies an axial thrust to the second threaded drive block 422 and the screw 630 connected thereto, pushing the screw 630 and the dynamic engagement block 640 to move axially, causing the dynamic engagement block 640 to disengage from the first direction bevel gear 243 and engage with the second direction bevel gear 244, and the screw 630 rotates in the opposite direction, and the middle slider 420 begins to move towards the second side slider 430. Similarly, at the other end, the second spring 432 can trigger a reversing action in the opposite direction. Therefore, the direction can be automatically reversed when the middle nozzle reaches the travel boundary, avoiding manual intervention or complex control logic, thus enabling the periodic waveform oscillation trajectory to be formed continuously and stably.

[0029] like Figure 6 and Figure 7As shown, to ensure that the screw 630 can stably maintain its corresponding axial position after reversing, a positioning component 620 is provided on the outer wall of the second housing 610. The positioning component 620 includes an elastic plate 621 and a ball seat 622 disposed on the elastic telescopic end of the elastic plate 621. Two adjacent annular grooves 623 are provided on the screw 630 corresponding to the position of the ball seat 622. When the screw 630 completes axial switching under the action of spring thrust, the ball seat 622 is engaged into one of the annular grooves 623 under the elastic action of the elastic plate 621, thereby positioning and maintaining the current axial position of the screw 630. This positioning method can, on the one hand, suppress axial movement of the screw 630 under working vibration conditions, and on the other hand, ensure that the dynamic meshing block 640 is in a relatively stable relative position when meshing with the first direction bevel gear 243 or the second direction bevel gear 244, thereby improving meshing reliability and transmission smoothness after reversing.

[0030] like Figures 1 to 8 As shown, in the assembled state of this embodiment, the path synchronization mechanism 200, concrete pipe 300, support frame 400, building width adjustment mechanism 500, and reinforcing rib adaptive width adjustment mechanism 600 are integrated into the same extrusion nozzle body. Before printing begins, the adjustment block 530 can be rotated to create a spacing between the first edge nozzle 310 and the second edge nozzle 320 that is adapted to the target wall width. At the same time, with the following guidance of the sleeve block 421, the middle oscillating nozzle 330 is positioned in the new width center area. Subsequently, the concrete pipe 300 feeds material to the three nozzles synchronously. The first edge nozzle 310 and the second edge nozzle 320 output edge material, while the middle oscillating nozzle 330 reciprocates and oscillates to output material under the combined action of the path synchronization mechanism 200 and the reinforcing rib adaptive width adjustment mechanism 600. This makes it easier to form a regular interlocking structure when the layers are stacked, thereby improving the interlayer bonding strength and overall stability of the printed wall.

[0031] In some embodiments, the polygonal transmission rod 220 may be a hexagonal rod, a square rod, or other non-circular cross-section rod capable of sleeve transmission; the adjusting block 530 may be a handwheel, a hexagonal head, or other adjusting end structure that facilitates manual force application; the sleeve block 421 may be a ring-shaped snap-fit ​​structure, a groove-shaped limiting structure, or other guiding structure that only allows it to move in a predetermined direction; the meshing interface between the dynamic meshing block 640 and the corresponding bevel gear may be spline-shaped, key-tooth-shaped, or other meshing structures capable of torque transmission. The above changes are all conventional substitutions made to the specific implementation form without altering the basic concept of this embodiment. They can maintain the reciprocating drive of the central nozzle and the adaptive adjustment of the width range while meeting different processing conditions or assembly requirements, thereby improving the engineering applicability of this embodiment.

[0032] In other embodiments, the flow equalization structure inside the concrete pipe 300, the nozzle sizes of the first side nozzle 310, the second side nozzle 320, and the central oscillating nozzle 330 can be adjusted according to the particle size distribution of the printing material, the target layer thickness, and the width of the reinforcing ribs. Linear guide pairs, wear-resistant sliding pairs, or rolling guide pairs can be provided between the support frame 400 and each slider to reduce running resistance. A dustproof sealing structure can be provided between the second outer shell 610 and the screw 630 to reduce the possibility of slurry particles or construction dust entering the transmission cavity. Through further optimization of the feeding, guiding, and protective interfaces, the extrusion nozzle can maintain good continuous working capability and structural reliability in the 3D printing construction environment, thereby improving the overall service life and forming stability.

[0033] In summary, the extrusion nozzle for interlocking concrete layer forming in this embodiment achieves mechanical force acquisition related to printing displacement through the path synchronization mechanism 200, synchronous width adjustment of the two edge nozzles through the building width adjustment mechanism 500, adaptive reciprocating motion of the middle swing nozzle 330 within the updated working range through the synergistic action of the screw 630, the second thread drive block 422, the sleeve block 421, the dynamic engagement block 640, and the spring reversing structure, and stable positioning of the screw 630 after reversing through the positioning component 620. Thus, edge forming, width adjustment, and middle interlocking layer forming are completed within an integrated nozzle body, thereby giving the printed structure good width adaptability, interlocking capability, and mechanical transmission reliability.

[0034] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. An extrusion nozzle for 3D printing interlocking concrete layers, characterized in that, It includes a path synchronization mechanism (200), concrete pipes (300), a support frame (400), a building width adjustment mechanism (500), and a reinforcing rib adaptive width adjustment mechanism (600); The concrete pipe (300) is connected to the first side nozzle (310), the second side nozzle (320) and the middle swing nozzle (330) respectively; The support frame (400) is movably provided with a first side slider (410), a middle slider (420) and a second side slider (430). The first side nozzle (310), the middle swing nozzle (330) and the second side nozzle (320) are respectively disposed at the bottom ends of the first side slider (410), the middle slider (420) and the second side slider (430). The middle slider (420) is located between the first side slider (410) and the second side slider (430). The building width adjustment mechanism (500) is disposed on one side of the support frame (400). The building width adjustment mechanism (500) includes a pull rod (520) disposed in the support frame (400) and having reverse threads on both sides. The first side slider (410) and the second side slider (430) are respectively screwed onto the reverse threads on both sides of the pull rod (520) through the first threaded drive block (411) and the third threaded drive block (431), so that when the pull rod (520) rotates, it drives the first side slider (410) and the second side slider (430) to move closer or further away from each other synchronously, thereby synchronously adjusting the distance between the first side nozzle (310) and the second side nozzle (320). The path synchronization mechanism (200) includes a ground wheel assembly (210), a counterweight transmission box (212), a polygonal transmission rod (220), and a reciprocating drive assembly (240). The ground wheel assembly (210) is used to obtain a rotational input corresponding to the printing displacement when the extrusion nozzle moves along the construction path with the printing equipment, and outputs it to the polygonal transmission rod (220) through the counterweight transmission box (212). The reciprocating drive assembly (240) is connected to the polygonal transmission rod (220) in a transmission connection. The reinforcing rib adaptive width adjustment mechanism (600) includes a second housing (610) and a screw (630) disposed in the second housing (610). The end of the middle slider (420) is provided with a second threaded drive block (422), which is screwed onto the screw (630). The end of the middle slider (420) away from the second threaded drive block (422) is provided with a sleeve block (421). The sleeve block (421) is horizontally moved and engaged in the building width adjustment mechanism (500) without contacting the tie rod (520), so that when the building width is adjusted, the middle slider (420) moves synchronously with the position changes of the first side slider (410) and the second side slider (430) and remains in the updated middle working range. The reciprocating drive assembly (240) includes a drive assembly input shaft (241), a drive bevel gear (242), a first direction bevel gear (243), and a second direction bevel gear (244). The drive assembly input shaft (241) is sleeved on the polygonal transmission rod (220). The drive bevel gear (242) is connected to the drive assembly input shaft (241) via a reversing transmission mechanism. The first direction bevel gear (243) and the second direction bevel gear (244) are coaxially opposite to each other and both are connected to the drive assembly input shaft (241). The active bevel gear (242) meshes, and the first directional bevel gear (243) and the second directional bevel gear (244) are both provided with channels for the axial movement of the screw (630). The outer wall of the screw (630) is fixedly sleeved with a dynamic meshing block (640). The dynamic meshing block (640) can switch to meshing with the first directional bevel gear (243) or the second directional bevel gear (244) as the screw (630) moves axially, so that the screw (630) can rotate forward or in reverse. A first spring (412) and a second spring (432) are respectively provided on the sidewalls of the first threaded drive block (411) and the third threaded drive block (431) that are close to each other. When the second threaded drive block (422) moves to the corresponding end of the stroke along with the middle slider (420), it can contact and compress the first spring (412) or the second spring (432) so as to push the screw (630) to move axially through the spring thrust and drive the dynamic meshing block (640) to switch the meshing position. The first edge nozzle (310) and the second edge nozzle (320) are used to output edge strips extending along the printing direction, and the middle oscillating nozzle (330) is used to output interlocking strips formed by reciprocating oscillation between the two.

2. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The ground wheel assembly (210) is provided with two rotating wheels (211), which are connected by a power shaft. The power shaft is connected to the counterweight transmission box (212), and the transmission box output end (213) of the counterweight transmission box (212) is connected to the polygonal transmission rod (220).

3. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The outer wall of the concrete pipe (300) is fitted with a support sleeve (230), the polygonal transmission rod (220) is rotatably passed through the support sleeve (230) via a support bearing sleeve (231), and the reciprocating drive assembly (240) is fixedly disposed on the side of the support frame (400).

4. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The first directional bevel gear (243) and the second directional bevel gear (244) continuously rotate with the driving bevel gear (242), and respectively output rotational driving forces in opposite directions to the screw (630).

5. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The building width adjustment mechanism (500) also includes a first housing (510) and an adjustment block (530) disposed at the end of the pull rod (520). When the external tool drives the adjustment block (530) to rotate, the first side slider (410) and the second side slider (430) perform mirror synchronous width adjustment movements.

6. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The outer wall of the second housing (610) is provided with a positioning component (620). The positioning component (620) includes an elastic sheet (621) and a ball seat (622) disposed on the elastic telescopic end of the elastic sheet (621). The screw (630) is provided with two adjacent annular slots (623) corresponding to the position of the ball seat (622). The ball seat (622) can be inserted into either of the annular slots (623) as the screw (630) moves axially, so as to position and maintain its axial position after the screw (630) completes the axial switching.

7. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The meshing interface between the dynamic meshing block (640) and the first directional bevel gear (243) and the second directional bevel gear (244) is a spline meshing interface or a key tooth meshing interface.

8. The extrusion nozzle for interlocking concrete layer forming in 3D printing according to claim 1, characterized in that, The concrete pipeline (300) is equipped with a flow equalization structure to distribute the incoming concrete flow to the first side nozzle (310), the second side nozzle (320), and the central oscillating nozzle (330).

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