3D printing device and gas circulation purification system thereof

Abstract

The application discloses a 3D printing device and a gas circulation purification system thereof, wherein the air inlet module is configured as a first air inlet assembly including a first air inlet structure, the air inlet amount is increased, and a stronger airflow is formed at the first air inlet; and the air outlet module is configured as a second air inlet assembly including a jet uniform speed structure, so that the distribution of the air speed in the vertical direction is more uniform, the air speed can still be high when the air reaches the air outlet module, and air speed attenuation is avoided.

Description

Technical Field

[0001] This application relates to the field of 3D printing technology, and in particular to a 3D printing device and its gas circulation and purification system. Background Technology

[0002] With the rapid development of industrial technology, various 3D printing technologies using powder materials as raw materials are emerging, such as Selective Laser Melting (SLM), Selective Laser Sintering (SLS), Direct Laser Metal Deposition (DLMD), Electron Beam Melting (EBM), and Selective Heat Sintering (SHS).

[0003] Taking SLM-based 3D printing equipment as an example, a large amount of smoke is generated in the forming chamber when the laser scans the metal powder. This smoke adheres to the protective lenses of the optical system, affecting the forming quality. Especially with the development of metal 3D printing technology, the industry's demand for printing large parts is increasing, requiring larger forming areas and placing higher demands on the design of the airflow. Currently, in large-format equipment, the airflow in the forming chamber generally suffers from wind speed attenuation due to the large distance between the air outlet and return air outlet. Furthermore, the larger the forming area, the more severe the wind speed attenuation. This attenuation makes it difficult to effectively remove the smoke from the forming chamber, which not only affects the cleaning effect of the optical protective lenses but also poses a dust explosion hazard within the forming chamber.

[0004] Therefore, how to design a gas circulation purification system with stable flow rate and effective removal of smoke from the molded indoor environment is a technical problem that urgently needs to be solved by those skilled in the art. Summary of the Invention

[0005] In view of the shortcomings of the above-mentioned related technologies, the purpose of this application is to provide a 3D printing device and its gas circulation and purification system to solve the technical problem that the wind field structure is difficult to effectively clean the smoke in the molding chamber due to wind speed attenuation in the related technologies.

[0006] To achieve the above and other related objectives, a first aspect of this application provides a gas circulation and purification system for a 3D printing device. The 3D printing device has a molding platform, and the gas circulation and purification system includes: a housing disposed on the molding platform to define a molding chamber; an air inlet module disposed on a side wall of one side of the housing for supplying gas to the molding chamber, comprising a first air inlet component disposed vertically and parallel to each other away from the molding platform and a second air inlet component disposed adjacent to the molding platform; wherein the size of the first air inlet of the first air inlet component is larger than the second air inlet of the second air inlet component to increase the air intake, and the second air inlet component includes a jet uniform velocity structure for supplying airflow to the molding platform; and an air outlet module disposed on the other side wall of the housing away from the air inlet module, comprising an air outlet component disposed corresponding to the second air inlet component for outputting airflow to the molding chamber.

[0007] A second aspect of this application provides a 3D printing device, comprising: a forming platform having a forming chamber thereon, the forming platform having a forming hopper, the forming hopper having a component platform and a Z-axis drive mechanism, the component platform being used to attach a 3D component formed layer by layer by irradiation from an optical system, the Z-axis drive mechanism being connected to the component platform and being used to controllably move vertically to adjust the distance between the component platform and the printing reference surface; a powder spreading system for spreading powder in the forming hopper; a gas circulation and purification system as described in any embodiment of the first aspect of this application for forming a circulating air field in the forming chamber; an optical system for emitting a light beam to irradiate the powder in the forming hopper; and a control device connected to the optical system, the Z-axis drive mechanism, and the powder spreading system for controlling the powder spreading system to spread powder in the forming hopper during a printing operation, controlling the optical system to irradiate the powder in the forming hopper, and controlling the Z-axis drive mechanism to move vertically during a printing operation to attach a solidified layer of a stacked pattern on the component platform to obtain a corresponding 3D component.

[0008] In summary, the 3D printing equipment and its gas circulation purification system provided in this application achieve airflow circulation within the molding chamber by setting up an air inlet module and an air outlet module. In particular, by setting up a first air inlet structure in the first air inlet component to increase the air intake volume, a stronger airflow is formed at the first air inlet, enhancing the cleaning effect on smoke. Furthermore, by setting up a jet uniform velocity structure in the second air inlet component, this application makes the air velocity distribution in the vertical direction more uniform, ensuring that the gas still has a high air velocity when it reaches the air outlet module, thereby reducing air velocity attenuation. Attached Figure Description

[0009] The specific features involved in this application are shown in the appended claims. A better understanding of the features and advantages of the invention can be achieved by referring to the exemplary embodiments and accompanying drawings described in detail below. A brief description of the drawings is as follows:

[0010] Figure 1 The diagram shown is a structural schematic of a 3D printing device according to one embodiment of this application.

[0011] Figure 2 The diagram shown is a structural schematic of a gas circulation and purification system in one embodiment of this application.

[0012] Figure 3 This application is displayed. Figure 2 A schematic diagram of gas flow in the gas circulation purification system shown in the embodiment.

[0013] Figure 4 The diagram shown is a structural schematic of the first air intake component in one embodiment of this application.

[0014] Figure 5 The diagram shown is a schematic diagram of the first air inlet structure in one embodiment of this application.

[0015] Figure 6 The diagram shown is a schematic diagram of the second air inlet structure in one embodiment of this application.

[0016] Figure 7 This diagram illustrates the wind speed reduction generated by a gas circulation and purification system in related technologies.

[0017] Figure 8 The diagram shown is a structural schematic of the second air intake component in one embodiment of this application.

[0018] Figure 9 The diagram shown is a schematic of a third air intake structure configured as a honeycomb panel in one embodiment of this application.

[0019] Figure 10 The diagram shown is a schematic diagram of the fourth air intake structure in one embodiment of this application.

[0020] Figure 11 The image shown is a wind field simulation diagram at a distance of 15 mm from the printed reference surface, obtained through flow field simulation analysis.

[0021] Figure 12 The diagram shows a simulated wind field at the vertical section of the second air inlet assembly, generated using flow field simulation analysis.

[0022] Figure 13 The diagram shown is a structural schematic of the air outlet component in one embodiment of this application. Detailed Implementation

[0023] The following specific embodiments illustrate the implementation of this application. Those skilled in the art can easily understand the advantages and technical effects of this application from the content disclosed in this specification. In the following description, some embodiments may be referenced to the accompanying drawings. It should be understood that other embodiments not shown in the drawings may also be used, and changes in specific structures, parts or mechanisms, components, and operations may be made without departing from the spirit and scope of this application. The following detailed description should not be considered limiting, and the scope of the embodiments of this application is limited only by the claims published in this application. The terminology used herein is for describing particular embodiments only and is not intended to limit this application.

[0024] It should be understood that although the terms first, second, or third, etc., may be used herein to describe various elements or parameters in some embodiments, these elements or parameters should not be limited by these terms. These terms are used only to distinguish one element or parameter from another, and not to define the order, priority, or importance of multiple elements. For example, a first air intake assembly may be referred to as a second air intake assembly, and similarly, a second air intake assembly may be referred to as a first air intake assembly, without departing from the scope of the various described embodiments.

[0025] Furthermore, as used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context indicates otherwise. It should be further understood that the terms “comprising,” “including,” and “including” indicate the presence of the stated features, steps, operations, elements, components, items, kinds, and / or groups, but do not exclude the presence, occurrence, or addition of one or more other features, steps, operations, elements, components, items, kinds, and / or groups. For example, a process, method, system, product, or device that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to these processes, methods, products, or devices. Additionally, the term “and / or,” which may be used hereinafter, describes the relationship between related objects, indicating that three relationships may exist; for example, A and / or B can represent: A alone, A and B simultaneously, and B alone. Furthermore, the character “ / ”, unless otherwise specified, generally indicates that the preceding and following related objects have an “and / or” relationship. Additionally, in the description of embodiments of this application, “multiple” refers to two or more. Furthermore, the terms “or” and “and / or” as used herein are interpreted as inclusive, or mean either one or any combination thereof. Exceptions to this definition only arise when a combination of elements, functions, steps, or operations is inherently mutually exclusive in some way.

[0026] It should also be understood that when an element, such as a layer, region, or substrate, is referred to as being "on" another element or extending "on" another element, the element may be directly on or directly extending onto the other element, or intermediate elements may be present. Conversely, when an element is referred to as being "directly on" another element or "directly extending onto" another element, no intermediate elements are present. It will also be understood that when an element is referred to as being "connected" or "attached" to another element, it may be directly connected or coupled to the other element, or intermediate elements may be present. Conversely, when an element is referred to as being "directly connected" or "directly coupled" to another element, no intermediate elements are present. Furthermore, the term "coupled" generally means physical, mechanical, magnetic, and / or electrical coupling or connection, and in the absence of specific contrasting language, the presence of intermediate elements between coupled or associated items is not excluded.

[0027] Relative terms such as “below,” “above,” “upper,” “lower,” “horizontal,” or “vertical” may be used herein to describe the relationship between one element, layer, or region and another element, layer, or region illustrated in the figures. It will be understood that these terms are intended to cover different device orientations other than those depicted in the figures. In this application, “vertical,” “horizontal,” and “parallel” are defined as including cases within ±10% of the standard definition. For example, vertical typically refers to an angle of 90° relative to a reference line, but in this application, vertical refers to cases including those within 80° to 100°. Unless otherwise expressly stated, comparative quantitative terms (such as “above” and “below”) are intended to cover the concept of equality. As an example, “above” can mean not only “greater than” in a mathematical sense but also “equal to.”

[0028] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application. When used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that, when used herein, the terms “comprising,” “including,” “containing,” and / or “comprising” designate the presence of the stated features, integers, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or combinations thereof.

[0029] In view of the technical problems mentioned in the background art, this application discloses a 3D printing device and its gas circulation and purification system. By setting an air inlet module and an air outlet module, the airflow is circulated in the molding chamber. On the one hand, this application sets a first air inlet structure in the first air inlet component to increase the air intake volume, so as to form a stronger airflow at the first air inlet and enhance the cleaning effect on smoke. On the other hand, this application sets a jet uniform velocity structure in the second air inlet component, so that the wind speed is more evenly distributed in the vertical direction, which can ensure that the gas still has a high wind speed when it reaches the air outlet module, thereby avoiding wind speed attenuation.

[0030] In this application, the 3D printing equipment is a device that uses powder as raw material and constructs 3D components by molding the powder layer by layer. The powder is a powdered material, including nylon powder, metal powder, plastic powder, ceramic powder, and mixed powders. The powder may be, for example, thermoplastic rubber (TPR) or thermoplastic elastomer; wherein the thermoplastic elastomer includes any one of polyurethane elastomer (TPU), nylon elastomer (TPAE), polyester elastomer (TPEE), EVA elastomer, and silicone elastomer, or a mixture of two or more materials.

[0031] The thermoplastic elastomer is a type of elastomer that exhibits the elasticity of rubber at room temperature and the plasticity of molding at high temperatures. It is a physical mixture of copolymers or polymers (usually plastics and rubber) and is composed of materials with thermoplastic and elastomer properties. Thermoplastic plastics are generally relatively easy to manufacture, for example, through injection molding.

[0032] In some embodiments, the powder material may also be polypropylene, acrylonitrile butadiene styrene (ABS), polycarbonate (PC), PC-ABS, PLA, polystyrene, lignin, polyamide, polyamide foam, polyamide with additives such as glass or metal particles, methyl methacrylate-acrylonitrile-butadiene-styrene copolymer, absorbable materials such as polymer-ceramic composites, and other similar materials suitable for SLS printing processes.

[0033] The 3D printing equipment can be an SLM type 3D printing equipment, an SLS type 3D printing equipment, a DLMD type 3D printing equipment, an EBM type 3D printing equipment, or an SHS type 3D printing equipment, etc. In the following embodiments, the 3D printing equipment will be described as an SLM type 3D printing equipment, and correspondingly, the powder material will be described as a metal material.

[0034] Please see Figure 1 The diagram shows a structural schematic of a 3D printing device in one embodiment of this application. Figure 1As shown, the 3D printing equipment includes a forming platform 1, a powder spreading system 2, an optical system 3, and a control device 4. The forming platform 1 has a forming chamber 11. The powder spreading system 2 is used to spread powder within the forming chamber 11. The optical system 3 is used to emit a light beam to irradiate the powder within the forming chamber 11. The control device 4 is connected to the powder spreading system 2 and the optical system 3, and is used to control the powder spreading system 2 to spread powder into the forming chamber 11 and to control the optical system 3 to irradiate the powder within the forming chamber 11 during printing operations.

[0035] In one embodiment, the forming platform 1 can serve as a base for the powder spreading system 2 to perform powder spreading operations, while also providing accommodating space for the forming chamber 11. In some examples, the shape of the forming chamber 11 can be a cube, cuboid, or other shapes, and its shape and size determine the range of 3D components that the 3D printing equipment can manufacture. For example, if the size of the forming chamber 11 is 600mm × 600mm × 400mm, then the maximum range of 3D components that the 3D printing equipment can print is no greater than 600mm × 600mm × 400mm.

[0036] In one embodiment, such as Figure 1 As shown, the forming platform 1 has a forming chamber 12, which can be formed, for example, by a housing 13 disposed above the forming platform 1. In some examples, the housing 13 can be detachably mounted to the forming platform 1 by means of screws, clips, etc. In some examples, an inert gas can be introduced into the forming chamber 12 for protection so that the powder is prevented from oxidizing at high temperatures when the entire printing operation of the 3D printing equipment is carried out in the forming chamber. Examples of inert gases are nitrogen or argon.

[0037] In one embodiment, the forming chamber 11 is provided with a component platform and a Z-axis drive mechanism. The component platform is used to attach the 3D component, which is formed layer by layer by an optical system. In one example, the component platform is in close contact with the inner wall of the forming chamber 11 and moves vertically under the drive of the Z-axis drive mechanism during printing. In some examples, the component platform has a heat conduction function to maintain a certain high-temperature environment within the forming chamber 11 to optimize print quality.

[0038] In one embodiment, the Z-axis drive mechanism is connected to the component platform and is used to move in a controlled vertical direction to adjust the distance between the component platform and the printing reference surface. Specifically, the control device 4 controls the Z-axis drive mechanism to adjust the distance between the component platform and the printing reference surface according to the thickness of each printed layer, that is, to adjust the height of the forming area. The forming area is the area formed by the printing reference surface and the upper surface of the component platform or the upper surface of the 3D component during the printing process.

[0039] In one embodiment, the Z-axis drive mechanism includes a drive unit and a Z-axis moving unit. The drive unit drives the Z-axis moving unit so that the Z-axis moving unit moves the component plate along the Z-axis direction. For example, the drive unit is a drive motor. The drive unit is controlled by control commands output by the control device. These control commands include directional commands indicating whether the component plate is rising, falling, or stopping, and may even include parameters such as rotational speed / speed acceleration or torque / torque. This facilitates precise control of the rising distance of the Z-axis moving unit, enabling precise adjustment of the Z-axis. Here, the Z-axis moving unit may include, for example, a fixed rod fixed at one end to the component plate and an engaging moving assembly fixed to the other end of the fixed rod. The engaging moving assembly is driven by the drive unit to move the fixed rod along the Z-axis direction. An example of the engaging moving assembly is a limiting moving assembly with a toothed structure, such as a rack. For example, the Z-axis moving unit includes a lead screw and a positioning and moving structure screwed to the lead screw, wherein both ends of the lead screw are screwed to a drive unit, and the outer end of the positioning and moving structure is fixedly connected to the component plate. The positioning and moving structure may be, for example, a ball screw.

[0040] In one embodiment, the optical system 3 includes a light source and a scanning galvanometer. The light source is used to controllably emit a beam of light with a preset intensity. The light source can be a laser, such as a fiber laser or a YAG laser. The choice of light source is related to different types of printing equipment. For example, in SLM-type 3D printing equipment that requires melting metal, the light source can be a high-power-density laser. The scanning galvanometer can be deflected under the drive of its drive motor. For example, the drive motor of the scanning galvanometer is controlled by control commands output by the control device. By adjusting the deflection angle of the scanning galvanometer, the propagation direction of the beam is adjusted to precisely position the beam at any position on the printing reference surface. The control commands include directional commands indicating whether the scanning galvanometer rotates or stops, and may even include parameters such as rotational speed / rotational acceleration.

[0041] In one specific embodiment, the optical system 3 includes a light source, a beam expander, a scanning galvanometer, an F-θ scanning lens, and a protective lens. The light beam emitted from the light source first passes through the beam expander, which increases the beam diameter, reduces the beam divergence angle, and decreases energy loss. After passing through the beam expander, the light beam reaches the scanning galvanometer, where the scanning galvanometer controls the beam's propagation direction. The F-θ scanning lens is positioned below the scanning galvanometer to converge the deflected light beam, allowing the light to form a focused spot at any position on the printing reference surface. The F-θ scanning lens also helps prevent optical distortion. The protective lens is positioned below the F-θ scanning lens, and the light beam finally passes through the protective lens to reach the printing reference surface. The protective lens prevents dust from affecting the optical components. In some examples, the optical system 3 may consist of one or more components.

[0042] In one embodiment, the control device 4, in addition to being connected to the powder spreading system 2 and the optical system 3, can also be connected to the Z-axis drive mechanism. This control device controls the Z-axis drive mechanism 141 to move vertically during a printing operation, thereby attaching a solidified layer of the deposited pattern to the component platform to obtain a corresponding 3D component. Specifically, the control device is electrically connected to the drive motor of the Z-axis drive mechanism, causing the Z-axis drive mechanism to move vertically to attach a solidified layer of the deposited pattern to the component platform to obtain a corresponding 3D component.

[0043] In one embodiment, the control device 4 is an electronic device containing a processor, such as a computer device, an embedded device, or an integrated circuit with a CPU, such as a control board or main control board.

[0044] For example, the control device includes a processing unit, a storage unit, and multiple interface units. Each interface unit is connected to an independently installed device in the 3D printing equipment, such as the powder spreading system 2, the optical system 3, and the Z-axis drive mechanism, and transmits data through the interface. The control device also includes at least one of the following: a prompting device, a human-computer interaction device, etc. The interface unit determines its interface type according to the connected device, which includes, but is not limited to: a universal serial interface, a video / image interface, and an industrial control interface, etc.

[0045] For example, the interface unit includes: a USB interface, an HDMI interface, and an RS232 interface. Multiple USB and RS232 interfaces are available. The USB interfaces can connect to human-computer interaction devices, etc. The RS232 interfaces connect to the powder spreading system 2 and the Z-axis drive mechanism. The HDMI interfaces connect to the optical system 3. The storage unit is used to store files required for 3D printing. These files include: program files and configuration files required for CPU operation, etc.

[0046] The storage unit includes non-volatile memory and a system bus. Examples of the non-volatile memory include solid-state drives (SSDs) or USB flash drives. The system bus connects the non-volatile memory to the CPU, wherein the CPU may be integrated into the storage unit or packaged separately from the storage unit and connected to the non-volatile memory via the system bus.

[0047] The processing unit includes at least one of the following: a CPU or a chip with an integrated CPU, a programmable logic device (FPGA), and a multi-core processor. The processing unit also includes memory, registers, and other storage devices for temporary data storage.

[0048] The processing unit serves as an industrial control unit that controls the sequential execution of each device. For example, after controlling the Z-axis drive mechanism to move the component platform to a position a distance away from the preset printing reference surface, the processing unit transmits a control signal to the drive motor of the powder spreading system 2 to control the powder spreading system 2 to perform powder spreading operations. After the powder spreading system 2 completes the powder spreading, the control device transmits control signals to the motors of the light source and galvanometer of the optical system 3. After the optical system 3 completes the curing of the powder on the component platform, it controls the Z-axis drive mechanism to adjust and move the component platform to a new position a distance away from the preset printing reference surface, repeating the above printing process until the printing of the entire 3D component is completed.

[0049] It should be understood that smoke is generated in the forming chamber during 3D printing using SLM equipment. This smoke refers to dust generated by powder being lifted during powder spreading, or high-melting-point spatter formed when the powder melts under laser pressure during laser scanning. This smoke may adhere to the scanning galvanometer of the optical system, causing severe power attenuation when the laser passes through the lens, preventing the powder in the forming chamber from fully melting and thus affecting the forming quality. Furthermore, the lens with smoke adhering to it will heat up due to absorbing laser energy, and may even crack due to high temperatures. Moreover, the smoke falling onto the forming platform 1 can cause impurities in the printed 3D components, affecting print quality. In addition, to prevent air from entering the forming chamber 12 and thus avoiding smoke explosions, a vacuum environment needs to be maintained inside the forming chamber before and after printing. Therefore, a wind tunnel structure is needed within the forming chamber 12 to promptly remove smoke and exhaust air.

[0050] In view of this, this application provides a gas circulation and purification system in some embodiments. The gas circulation and purification system is used to form a stable circulating air field in the molding chamber 12 and continuously and stably blow inert gases such as nitrogen or argon into the molding chamber. In subsequent embodiments, the gas / airflow includes pure inert gas / airflow initially introduced into the molding chamber 12 before 3D printing and low-oxygen inert gas / airflow after circulation treatment during the printing process.

[0051] Please see Figure 2 The diagram shows a structural schematic of a gas circulation and purification system in one embodiment of this application. Figure 2 As shown, the gas circulation and purification system 5 includes a housing 13, an air inlet module 51, and an air outlet module 52. The housing 13 is disposed on the molding platform 1 to define the molding chamber 12. The housing 13 is configured as the housing 13 included in the 3D printing equipment of the aforementioned embodiment, and the molding chamber 12 is configured as the molding chamber 12 included in the 3D printing equipment of the aforementioned embodiment. The air inlet module 51 is used to supply gas to the molding chamber 12. The air outlet module 52 is used to output gas from the molding chamber 12.

[0052] In one embodiment, such as Figure 2 As shown, the air inlet module 51 is disposed on the side wall of one side of the housing 13 and is used to supply gas to the molding chamber 12. In one embodiment, as... Figure 2 As shown, the air outlet module 52 is located on the side wall of the housing 13 away from the air inlet module 51, and is used to output gas carrying smoke. Specifically, the gas can enter the molding chamber 12 through the air inlet module 51, and then carry the smoke out of the molding chamber 12 through the air outlet module 52.

[0053] In one embodiment, such as Figure 2 As shown, the air intake module 51 includes a first air intake component 511 and a second air intake component 512 that are vertically spaced and arranged parallel to each other. The first air intake component 511 is away from the molding platform 1, and the second air intake component 512 is adjacent to the molding platform 1. It should be noted here that, for the purpose of clarifying the definition of direction and the operation between different structures, the vertical direction in the foregoing and following embodiments of this application refers to the vertical direction or the up-down direction (as shown in the figure). Figure 7 (The direction of arrow Y in the image).

[0054] exist Figure 2 In the illustrated embodiment, the first air inlet assembly 511 is located on the upper side of the molding chamber 12, and the second air inlet assembly 512 is located on the lower side of the molding chamber. Please refer to [link / reference]. Figure 3 This application is displayed as such. Figure 2 A schematic diagram of gas flow in the gas circulation and purification system shown in the embodiment. Figure 3As shown, the first air inlet assembly 511 has a first air inlet 5111 to form a first airflow F1 within the molding chamber 12. The second air inlet assembly 512 has a second air inlet 5121 to form a second airflow F2 within the molding chamber 12, thereby achieving airflow at different height levels within the molding chamber 12. Specifically, the first airflow F1 prevents the swirling of lower-level gas, thus effectively preventing smoke from obscuring the scanning galvanometer of the optical system. The second airflow F2 prevents smoke from depositing in the lower layers, thus avoiding contamination of the 3D components. In some examples, the first air inlet 5111 and the second air inlet 5121 may be configured as openings connecting the first air inlet assembly 511 and the sidewall of the molding chamber 12, and connecting the second air inlet assembly 512 and the sidewall of the molding chamber 12, respectively.

[0055] Of course, in some other embodiments, the air intake module 51 may also be configured to include more than two air intake components, for example, it may be configured as three sets of air intake components arranged evenly in the vertical direction, depending on the actual needs.

[0056] In one embodiment, the size of the first air inlet 5111 of the first air inlet assembly 511 is larger than the size of the second air inlet 5121 of the second air inlet assembly 512 to increase the air intake volume. In this embodiment, the size can be understood as the total cross-sectional area of ​​the openings at the first air inlet 5111 or the second air inlet 5121 that allow air intake. A larger air intake volume at the first air inlet 5111 than at the second air inlet 5121 increases the flow rate and velocity of the first airflow F1, thereby creating a stronger airflow to further prevent smoke from adhering to the scanning galvanometer of the optical system, thus ensuring printing quality. Furthermore, increasing the air intake volume at the first air inlet 5111 also increases the total airflow within the forming chamber 12, allowing the gas to exit the forming chamber 12 more smoothly through the exhaust module 52.

[0057] Please see Figure 4 The image shown is a structural schematic diagram of the first air inlet assembly in one embodiment of this application. Figure 4 As shown, the first air inlet 5111 is equipped with a first air inlet structure 5112. Please refer to [link / reference]. Figure 5 The image shown is a schematic diagram of the first air inlet structure in one embodiment of this application. Figure 5 As shown, the first air inlet structure 5112 has multiple first air inlet holes 51121 with the same aperture. In this example, the identical aperture of the multiple first air inlet holes 51121 allows gas to pass through uniformly, which helps to establish a uniform and stable laminar flow field on the upper side of the forming chamber 12. It should be noted that, in this embodiment, the size of the first air inlet 5111 is the sum of the areas of all the first air inlet holes 51121 on the first air inlet structure 5112.

[0058] In one embodiment, such as Figure 5 As shown, the first air inlet structure 5112 is configured as a perforated plate, and the diameter of the first air inlet hole 51121 is any value between 1 and 5 mm. In some examples, the diameter of the first air inlet 51121 can be approximately 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, or 5mm, etc. In a preferred example, the diameter of the first air inlet 51121 is 3mm.

[0059] Of course, in some other embodiments, the first air inlet structure 5112 may also be configured as other structures, such as a square perforated plate, a polygonal perforated plate, or a slotted plate, etc., which can be determined according to the design of the wind field, and this application does not impose any restrictions on this.

[0060] In one embodiment, such as Figure 4 As shown, the first air inlet assembly 511 includes a first air inlet 5111 and a first air inlet duct 5113, which connects to the first air inlet 5111. Specifically, gas enters the first air inlet duct 5113 and then enters the first air inlet 5111 to be input into the molding chamber 12. In some examples, the first air inlet duct 5113, as a key channel structure for inputting gas into the molding chamber 12, needs to have high sealing performance to prevent external air from entering. In some examples, to reduce flow resistance, the inner wall of the first air inlet duct 5113 is smooth and the bends are rounded to ensure smooth gas flow. In some examples, the first air inlet duct 5113 is configured as a high-strength structure resistant to high temperatures, such as stainless steel, to prevent the pipe from deforming during gas transportation.

[0061] In one embodiment, such as Figure 4 As shown, a second air inlet structure 5114 for uniform air velocity is provided on the first air inlet duct 5113. In this embodiment, it is presented as follows: Figure 4As indicated by the dashed arrow, the gas enters the first air inlet duct 5113, passes sequentially through the second air inlet structure 5114, the first air inlet structure 5112 at the first air inlet 5111, and then enters the forming chamber 12. When the gas flows through the second air inlet structure 5114, it is optimized to form a uniform airflow, ensuring the stability of the airflow and the uniformity of the wind speed, further reducing eddies or turbulence, and thus improving the stability of the airflow field within the forming chamber 12.

[0062] In one embodiment, such as Figure 4 As shown, the pipe diameter at the second air inlet structure 5114 is smaller than the pipe diameter at the first air inlet structure 5112. In this embodiment, as the gas flows from the second air inlet structure 5114 to the first air inlet pipe 5113, the pipe diameter gradually increases, thereby increasing the air intake volume and reducing the flow velocity. This reduces the airflow impact force and helps to form a more stable and uniform flow field. In addition, the gradually increasing pipe diameter allows for a more uniform pressure distribution when the gas enters the forming chamber 12, avoiding disturbances caused by local high pressure.

[0063] Please see Figure 6 The image shown is a schematic diagram of the second air inlet structure in one embodiment of this application. Figure 6 As shown, the second air inlet structure 5114 is configured as a square hole plate, which has a plurality of square holes 51141 of the same size, and the side length of the square holes 51141 is any value between 1 and 5 mm. In some examples, the side length of the square hole 51141 can be approximately 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, or 5mm, etc. In a preferred example, the side length of the square hole 51141 is 3mm.

[0064] Of course, in some other embodiments, the second air inlet structure 5114 may also be configured as other structures, such as a circular perforated plate, a polygonal perforated plate, or a slotted plate, etc., which can be determined according to the design of the wind field, and this application does not impose any restrictions on this.

[0065] It should be noted that the circulating airflow used for smoke removal in the relevant technologies suffers from reduced wind speed, making it difficult to effectively remove smoke from the forming chamber, resulting in poor cleaning performance. For details, please refer to... Figure 7 This is a schematic diagram illustrating the wind speed reduction in a gas circulation and purification system within a related technology. It should be noted that... Figure 7 The rectangular box in the diagram illustrates the air intake module 51 in the gas circulation and purification system. The arrow indicated by X shows the flow direction of the gas within the forming chamber 12. Multiple arrows arranged parallel to each other along the Y direction represent the gas, with the length of the arrows representing the gas flow velocity. In the foregoing and subsequent embodiments, for example in… Figure 3 and Figure 8 In the diagram, multiple parallel arrows still indicate the gas, and the length of the arrows still represents the gas flow velocity, which will not be repeated in subsequent embodiments.

[0066] like Figure 7 As shown, in related technologies, based on the gas jet principle, after the gas input from the air inlet module 51 enters the forming chamber 12, the gas diffuses along the Y direction because the cross-sectional area of ​​the cavity inside the forming chamber 12 is larger than that of the air inlet module 51 in the Y direction. This causes the gas velocity along its flow direction to gradually decrease, resulting in a reduction in the velocity when flowing towards the air outlet module 52. Furthermore, the gas near the forming platform 1 is more susceptible to the frictional resistance of the laid powder layer, further exacerbating the attenuation of the gas flow towards the air outlet module 52.

[0067] Therefore, please continue reading Figure 2 and Figure 3 ,like Figure 2 and Figure 3 As shown, the second air inlet assembly 512 includes a jet velocity uniform structure 513 for conveying airflow to the forming platform 1. The jet velocity uniform structure 513 enables a more uniform distribution of airflow velocity in the vertical direction and ensures that the gas maintains a high airflow velocity upon reaching the air outlet module 52, thereby avoiding the problem of airflow velocity attenuation. Specifically, it is presented as follows... Figure 3 The airflow of the second airflow F2 shown in the figure gradually becomes more uniform and stable as it flows from the second air inlet 5121 to the air outlet module 52.

[0068] Please see Figure 8 and combined Figure 2 ,in, Figure 8 The diagram shown is a structural schematic of the second air inlet assembly in one embodiment of this application. Figure 2 and Figure 8As shown, the jet uniform velocity structure 513 includes a third air inlet structure 5131, which is disposed at the second air inlet 5121 to stabilize the airflow direction. In this embodiment, the third air inlet structure 5131 can provide a longitudinal airflow uniformity effect. The longitudinal airflow uniformity effect means that the third air inlet structure 5131 can constrain the direction and velocity of the passing airflow in the vertical direction, so that the airflow distribution is uniform and the airflow enters the forming chamber 12 in a direction parallel to the forming platform.

[0069] In one embodiment, the third air inlet structure 5131 is configured as a honeycomb panel. See also... Figure 9 The image shows a schematic diagram of a third air inlet structure configured as a honeycomb panel in one embodiment of this application. In this embodiment, the third air inlet structure 5131 has multiple regularly arranged hexagonal through holes, forming a honeycomb shape to allow stable airflow. In some examples, the third air inlet structure 5131 has a certain thickness so that the through holes have a certain depth along the airflow direction, converting the airflow through the honeycomb panel into parallel and uniform laminar flow, thereby enhancing the airflow uniformity and improving the flow stability of the gas. In other examples, the through holes on the third air inlet structure 5131 can also be configured as circular, rectangular, or pentagonal, etc.

[0070] In one embodiment, such as Figure 8 As shown, the second air inlet assembly 512 further includes a second air inlet duct 5122, which connects to the second air inlet 5121. Specifically, gas enters the second air inlet duct 5122, then enters the second air inlet 5121, and finally enters the forming chamber 12 through the jet uniform velocity structure 513. In some examples, the second air inlet duct 5122 has high sealing performance to prevent external air from entering. In some examples, the inner wall of the second air inlet duct 5122 is smooth and the bends are rounded to ensure smooth gas flow. In some examples, the second air inlet duct 5122 is configured as a high-strength structure resistant to high temperatures, such as stainless steel, to prevent pipe deformation during gas transport.

[0071] In one embodiment, such as Figure 8 As shown, the jet uniform velocity structure 513 further includes a fourth air inlet structure 5132, which is disposed in the second air inlet duct 5122 and located upstream of the third air inlet structure 5131 for adjusting the vertical air velocity. In this embodiment, it is presented as follows: Figure 8As indicated by the arrows, the gas enters the second air inlet duct 5122, passes through the fourth air inlet structure 5132 and the third air inlet structure 5131 at the second air inlet 5121, and then enters the forming chamber 12. When the gas flows through the fourth air inlet structure 5132, a vertical velocity gradient gradually decreases from top to bottom, thus forming a stable jet. This jet with a vertical velocity gradient reduces the sudden dispersion of kinetic energy when the gas directly enters the forming chamber 12, allowing the airflow to maintain a high speed. Furthermore, the airflow velocity gradually transitions to a stable state in its flow direction, suppressing airflow turbulence, so that the airflow remains high and stable when it reaches the outlet module 52, thereby enhancing the airflow's ability to carry smoke away from the forming chamber.

[0072] Please see Figure 10 The diagram shown is a schematic representation of the fourth air inlet structure in one embodiment of this application. Figure 10 As shown, the fourth air inlet structure 5132 is configured as a vertically variable diameter orifice plate with the orifice diameter gradually decreasing from top to bottom. In some examples, the vertically variable diameter orifice plate has multiple sets of orifice structures, each set of orifice structures can occupy multiple layers on the vertically variable diameter orifice plate, presenting an overall state of gradually decreasing orifice diameter from top to bottom. Figure 10 In the examples shown, the hole structures on the vertical variable diameter orifice plate are all configured as square holes. In some other examples, the hole structures may also be configured as through holes of other shapes such as circular holes or polygonal holes.

[0073] In one embodiment, such as Figure 10 As shown, the vertically variable diameter orifice plate has a first orifice group 51321, a second orifice group 51322, and a third orifice group 51323 arranged sequentially from top to bottom. In some other embodiments, more orifice groups may be provided on the vertically variable diameter orifice plate, such as four, five, or more groups, as long as a vertical wind speed gradient can be formed. This application does not impose any restrictions on this.

[0074] In one embodiment, the size of the third hole group 51323 is any value between 1 and 5 mm, the size of the second hole group 51322 is 1.5 times that of the third hole group 51323, and the size of the first hole group 51321 is twice that of the third hole group 51323. In an example where the first hole group 51321, the second hole group 51322, and the third hole group 51323 are all configured as square holes, the size is the side length of the first hole group 51321, the second hole group 51322, and the third hole group 51323. For example, in some examples, the dimensions of the third hole group 51323 can be approximately 1mm, 1.1mm, 1.2mm, 1.3mm, 1.4mm, 1.5mm, 1.6mm, 1.7mm, 1.8mm, 1.9mm, 2mm, 2.1mm, 2.2mm, 2.3mm, 2.4mm, 2.5mm, 2.6mm, 2.7mm, 2.8mm, 2.9mm, 3mm, 3.1mm, 3.2mm, 3.3mm, 3.4mm, 3.5mm, 3.6mm, 3.7mm, 3.8mm, 3.9mm, 4mm, 4.1mm, 4.2mm, 4.3mm, 4.4mm, 4.5mm, 4.6mm, 4.7mm, 4.8mm, 4.9mm, or 5mm, etc. In a preferred example, the dimension of the third hole group 51323 is 3mm.

[0075] In the above example, the dimensions of the second hole group 51322 are respectively 1.5mm, 1.65mm, 1.8mm, 1.95mm, 2.1mm, 2.25mm, 2.4mm, 2.55mm, 2.7mm, 2.85mm, 3mm, 3.15mm, 3.3mm, 3.45mm, 3.6mm, 3.75mm, 3.9mm, 4.05mm, 4.2mm, 4.35mm, 4.5mm, 4.65mm, 4.8mm, 4.95mm, 5.1mm, 5.25mm, 5.4mm, 5.55mm, 5.7mm, 5.85mm, 6mm, 6.15mm, 6.3mm, 6.45mm, 6.6mm, 6.75mm, 6.9mm, 7.05mm, 7.2mm, 7.35mm, or 7.5mm, etc. In a preferred example where the size of the third hole group 51323 is 3 mm, the size of the second hole group 51322 is 4.5 mm.

[0076] The dimensions of the first hole group 51321 are respectively 2mm, 2.2mm, 2.4mm, 2.6mm, 2.8mm, 3mm, 3.2mm, 3.4mm, 3.6mm, 3.8mm, 4mm, 4.2mm, 4.4mm, 4.6mm, 4.8mm, 5mm, 5.2mm, 5.4mm, 5.6mm, 5.8mm, 6mm, 6.2mm, 6.4mm, 6.6mm, 6.8mm, 7mm, 7.2mm, 7.4mm, 7.6mm, 7.8mm, 8mm, 8.2mm, 8.4mm, 8.6mm, 8.8mm, 9mm, 9.2mm, 9.4mm, 9.6mm, 9.8mm, or 10mm, etc. In the preferred example where the dimension of the third hole group 51323 is 3mm, the dimension of the first hole group 51321 is 6mm.

[0077] In one embodiment, such as Figure 2 and Figure 8 As shown, the jet velocity uniform structure 513 includes a third air inlet structure 5131, a fourth air inlet structure 5132, and a fifth air inlet structure 5133. The fifth air inlet structure 5133 is disposed in the second air inlet duct 5122 and located upstream of the fourth air inlet structure 5132 to uniformize the air velocity. In this embodiment, the gas passes sequentially from the fifth air inlet structure 5133 through the fourth air inlet structure 5132 and the third air inlet structure 5131 to form a stable high-speed airflow at the second air inlet 5121.

[0078] In one embodiment, the fifth air inlet structure 5133 is configured as a perforated plate with a plurality of square holes of the same size, the side length of which is any value between 1 and 5 mm. For example, it can be approximately 1 mm, 1.1 mm, 1.2 mm, 1.3 mm, 1.4 mm, 1.5 mm, 1.6 mm, 1.7 mm, 1.8 mm, 1.9 mm, 2 mm, 2.1 mm, 2.2 mm, 2.3 mm, 2.4 mm, 2.5 mm, 2.6 mm, 2.7 mm, 2.8 mm, 2.9 mm, 3 mm, 3.1 mm, 3.2 mm, 3.3 mm, 3.4 mm, 3.5 mm, 3.6 mm, 3.7 mm, 3.8 mm, 3.9 mm, 4 mm, 4.1 mm, 4.2 mm, 4.3 mm, 4.4 mm, 4.5 mm, 4.6 mm, 4.7 mm, 4.8 mm, 4.9 mm, or 5 mm, etc. In a preferred example, the side length of the square hole is 3 mm.

[0079] Specifically, the gas simultaneously enters the first air intake assembly 511 and the second air intake assembly 512 through the first air intake duct 5113 and the second air intake duct 5122, respectively. In the first air intake duct 5113, the gas first passes through the square holes on the second air intake structure 5114, where it is optimized to form a uniform airflow. Then, it passes through the evenly distributed round holes on the first air intake structure 5112, resulting in a first airflow F1 with a large intake volume and uniform velocity being output from the first air intake port 5111 into the forming chamber 12. In the second air intake duct 5122, the gas first passes through the square holes on the fifth air intake structure 5133, forming a uniform airflow. Then, it passes through the first hole group 51321, the second hole group 51322, and the third hole group 51323 on the fourth air intake structure 5132, forming an airflow with a gradually decreasing velocity from top to bottom. Then, through the honeycomb holes of the third air inlet structure 5131, a second airflow F2 with a vertical velocity gradient is output into the forming chamber 12 from the second air inlet 5121. The velocity of the second airflow F2 can gradually transition to a stable state while maintaining a high velocity. Then, the first airflow F1 and the second airflow F2 merge at the air outlet module 52 to carry the smoke away from the forming chamber 12.

[0080] In the embodiments of the gas circulation purification system 5 described above in this application, a jet velocity uniform structure 513, including a third air inlet structure 5131, a fourth air inlet structure 5132, and a fifth air inlet structure 5133, is provided in the second air inlet component 512. The fourth air inlet structure 5132 is configured as a vertically variable diameter orifice plate capable of forming a vertical wind speed gradient. Simultaneously, the uniform wind speed of the third air inlet structure 5131 and the fifth air inlet structure 5133 is utilized to output a uniform and high-speed airflow to the air outlet module 52, thus mitigating the attenuation of wind speed. To illustrate the effect of the above-described airflow entry structure design, experimental data from a test example are provided here.

[0081] In the flow field simulation test example, the second air inlet component 512 is configured as described above.

[0082] Please see Figure 11 and Figure 12 , Figure 11 The image displayed is a wind field simulation diagram taken at a distance of 15 mm from the printed reference surface, obtained through flow field simulation analysis. Figure 12 The diagram shows a simulated wind field at the vertical section of the second air inlet assembly, generated using flow field simulation analysis. (Example) Figure 11 and 12As shown, the airflow is directed from the second air inlet 5121 into the air outlet module 52 within the forming chamber 12. The vertically variable diameter air inlet design ensures that the protective air field generated by the second air inlet component 512 does not attenuate the wind speed at the dust accumulation section 15mm above the forming surface, and even increases it. This ensures that the wind speed at the return air outlet achieves the dust removal effect. The airflow in the air field gradually stabilizes the wind speed using the gas jet principle, forming a uniform and high-speed air field.

[0083] In one embodiment, such as Figure 2 As shown, the air outlet module 52 of the gas circulation purification system 5 includes an air outlet component 521, which is configured to output airflow to the forming chamber 12, corresponding to the second air inlet component 512. In this embodiment, the air outlet module 52 is configured with only one air outlet component. In some other embodiments, the air outlet module 52 may be configured with multiple air outlet components, such as two air outlet components, which are respectively configured to correspond to the first air inlet component 511 and the second air inlet component 512.

[0084] Please see Figure 13 The image shown is a structural schematic diagram of the air outlet component in one embodiment of this application. Figure 13 As shown, the air outlet assembly 521 includes an inner air outlet 5211, an outer air outlet 5212, and an air outlet duct 5213 connecting the inner air outlet 5211 and the outer air outlet 5212. The gas from the first air inlet assembly 511 and the second air inlet assembly 512 merges at the inner air outlet 5211 and is then output to the air outlet duct 5213 through the outer air outlet 5212.

[0085] In one embodiment, such as Figure 13 As shown, the inner air outlet 5211 is configured as a trumpet-shaped structure to increase the airflow velocity. It should be understood that when the first airflow F1 and the second airflow F2 converge at the inner air outlet 5211, the gas flow rate is large and the kinetic energy is strong. At this time, the trumpet-shaped structure provides a gradually expanding flow channel, allowing the gas to smoothly enter the inner air outlet 5211, reducing flow resistance and avoiding turbulence. The larger opening in the trumpet-shaped structure can expand the suction range of the forming chamber 12 and improve the smoke absorption rate; the smaller opening can increase the airflow velocity and accelerate the smoke discharge speed.

[0086] The horn-shaped air vent structure gradually decreases in size from a large opening to a small opening, and then increases back to a normal opening. The air velocity is highest at the small opening, which is beneficial for the absorption of smoke and dust; the large opening expands the air intake range within the shaped chamber, increasing the smoke extraction rate. The function of the uniform air intake is to distribute the air intake pressure and improve the uniformity of the air intake capacity.

[0087] In one embodiment, such as Figure 13As shown, the outlet vent 5212 is configured as a converging structure for dispersing air pressure. In one example, the converging structure is progressively narrowing to provide a gradually decreasing flow channel cross-section along the gas flow direction, thereby reducing the difference in airflow velocity between the airflow center and the edge positions, making the suction pressure more evenly distributed, and thus improving the uniformity of suction capacity.

[0088] Specifically, the aforementioned first airflow F1 and second airflow F2 converge at the inner air outlet 5211, flow through the inner air outlet 5211 of the trumpet-shaped structure, and are then output to the air outlet duct 5213 through the closing structure of the outer air outlet 5212.

[0089] In one embodiment, the gas circulation and purification system 5 may further include a circulation pipeline connecting the air inlet module 51 and the air outlet module 52 to form a circulating air field within the forming chamber 12. Specifically, gas can enter the forming chamber 12 via the first air inlet assembly 511 and the second air inlet assembly 512 to form a gas carrying smoke that is output to the air outlet assembly 521. The output gas can be purified and reintroduced into the first air inlet assembly 511 and the second air inlet assembly 512 for the next cleaning operation.

[0090] In one embodiment, a gas purification device is provided on the circulation pipeline to filter and collect smoke from the gas blown out from the air outlet assembly 521, so that the purified gas re-enters the molding chamber 12 through the first air inlet assembly 511 and the second air inlet assembly 512, ensuring that the molding atmosphere in the molding chamber 12 is in an optimal state. In one example, the gas purification device is configured as a cyclone separator.

[0091] In one embodiment, a condenser assembly is provided on the circulation pipeline to cool the gas. It should be understood that the surface of the component platform provides a high-temperature environment for the printing operation, and the gas is also heated as it flows over the component surface. To prevent the gas temperature from continuously rising during circulation and affecting the normal operation of the components within the forming chamber 12, cooling treatment is required before the gas enters the forming chamber 12 each time. In some examples, the condenser assembly can be configured as a vortex tube cooler, a fluidized bed, or an air conditioner, etc., and the cooling capacity of the condenser assembly can be determined according to actual production needs.

[0092] In summary, the 3D printing equipment and its gas circulation purification system disclosed in this application realize the circulation of airflow in the molding chamber by setting an air inlet module and an air outlet module. On the one hand, this application sets a first air inlet structure in the first air inlet component to increase the air intake volume, thereby forming a stronger airflow at the first air inlet and enhancing the cleaning effect on smoke. On the other hand, by setting a jet uniform velocity structure in the second air inlet component, the wind speed is more evenly distributed in the vertical direction, which can ensure that the gas still has a high wind speed when it reaches the air outlet module, thereby reducing the wind speed attenuation to a certain extent.

[0093] The above embodiments are merely illustrative of the inventive essence and beneficial effects of this application, and are not intended to limit this application. Any person skilled in the art can modify or alter the above embodiments without departing from the principles and scope of this application. Therefore, all equivalent modifications or alterations achieved by those skilled in the art without departing from the spirit and technical concept disclosed in this application should still be covered by the claims of this application.

Claims

1. A gas circulation and purification system for a 3D printing device, the 3D printing device having a molding platform, characterized in that, The gas circulation and purification system includes: A housing is disposed on the molding platform to define a molding chamber with the molding platform; An air inlet module, disposed on a side wall of one side of the housing, is used to supply gas to the molding chamber. It includes a first air inlet component that is vertically spaced and parallel to each other and is located away from the molding platform, and a second air inlet component that is adjacent to the molding platform. The first air inlet of the first air inlet component is larger than the second air inlet of the second air inlet component to increase the air intake. The second air inlet component includes a jet uniform velocity structure for supplying airflow to the molding platform. An air outlet module is disposed on the side wall of the housing away from the air inlet module, and includes an air outlet component disposed corresponding to the second air inlet component for outputting airflow to the molding chamber.

2. The gas circulation and purification system for 3D printing equipment according to claim 1, characterized in that, The first air inlet is provided with a first air inlet structure having multiple first air inlet holes of the same diameter.

3. The gas circulation and purification system for 3D printing equipment according to claim 2, characterized in that, The first air inlet structure is configured as a perforated plate, and the diameter of the first air inlet hole is any value between 1 and 5 mm.

4. The gas circulation and purification system for 3D printing equipment according to claim 3, characterized in that, The first air intake assembly further includes a first air intake duct connected to the first air intake port. The first air intake duct is provided with a second air intake structure for uniform air velocity. The diameter of the second air intake structure is smaller than the diameter of the first air intake structure.

5. The gas circulation and purification system for 3D printing equipment according to claim 4, characterized in that, The second air inlet structure is configured as a square hole plate with multiple square holes of the same size, wherein the side length of the square holes is any value between 1 and 5 mm.

6. The gas circulation and purification system for 3D printing equipment according to claim 1, characterized in that, The jet uniform velocity structure includes a third air inlet structure disposed at the second air inlet for stabilizing the airflow direction, the third air inlet structure being configured as a honeycomb panel.

7. The gas circulation and purification system for 3D printing equipment according to claim 6, characterized in that, The second air intake assembly further includes a second air intake duct connected to the second air intake port, and the jet uniform velocity structure further includes a fourth air intake structure disposed in the second air intake duct and located upstream of the third air intake structure for adjusting the vertical wind speed.

8. The gas circulation and purification system for 3D printing equipment according to claim 7, characterized in that, The fourth air inlet structure is configured as a vertically variable diameter orifice plate with the orifice diameter gradually decreasing from top to bottom.

9. The gas circulation and purification system for 3D printing equipment according to claim 8, characterized in that, The vertical variable diameter orifice plate has a first group of holes, a second group of holes, and a third group of holes arranged from top to bottom; the size of the third group of holes is any value between 1 and 5 mm, the size of the second group of holes is 1.5 times that of the third group of holes, and the size of the first group of holes is twice that of the third group of holes.

10. The gas circulation and purification system for 3D printing equipment according to claim 7, characterized in that, The jet velocity uniform structure further includes a fifth air inlet structure disposed in the second air inlet duct and located upstream of the fourth air inlet structure for uniform air velocity; the gas passes through the fifth air inlet structure in sequence through the fourth air inlet structure and the third air inlet structure to form a high-speed airflow with stable flow velocity at the second air inlet.

11. The gas circulation and purification system for 3D printing equipment according to claim 10, characterized in that, The fifth air inlet structure is configured as a square hole plate with multiple square holes of the same size, wherein the side length of the square holes is any value between 1 and 5 mm.

12. The gas circulation and purification system for 3D printing equipment according to claim 1, characterized in that, The air outlet assembly includes an inner air outlet, an outer air outlet, and an air outlet duct connecting the inner air outlet and the outer air outlet. The gases from the first air inlet assembly and the second air inlet assembly converge at the inner air outlet and are then output through the outer air outlet into the air outlet duct.

13. The gas circulation and purification system for 3D printing equipment according to claim 12, characterized in that, The inner air outlet is configured as a trumpet-shaped structure to increase wind speed, and the outer air outlet is configured as a constricting structure to disperse air pressure.

14. A 3D printing device, characterized in that, include: A molding platform is provided with a molding chamber. The molding platform has a molding compartment, and a component platform and a Z-axis drive mechanism are provided inside the molding compartment. The component platform is used to attach 3D components that are formed layer by layer by irradiation by an optical system. The Z-axis drive mechanism is connected to the component platform and is used to move in a controlled manner along the vertical direction to adjust the distance between the component platform and the printing reference surface. A powder spreading system is used to spread powder within the forming chamber; The gas circulation purification system as described in any one of claims 1-13 is used to form a circulating air field in the molding chamber; An optical system is used to emit a light beam to illuminate the powder inside the molding chamber; A control device, connected to the optical system, Z-axis drive mechanism, and powder spreading system, is used to control the powder spreading system to spread powder into the forming chamber during printing operations, control the optical system to irradiate the powder in the forming chamber, and control the Z-axis drive mechanism to move vertically during printing operations to attach a solidified layer of the deposited pattern on the component platform to obtain the corresponding 3D component.

Images