Hopper, 3D printing feed device and 3D printing equipment

Abstract

The present disclosure provides a hopper, a 3D printing material supply device and a 3D printing equipment, and belongs to the technical field of 3D printing. The hopper comprises a shell, a base, which separates the inner cavity of the shell into at least: a containing cavity, an airflow cavity. The airflow cavity comprises a first cavity provided with a heating mechanism, a second cavity provided with an airflow driving mechanism, and a third cavity. The airflow driving mechanism, the first cavity, the second cavity and the containing cavity constitute an inner circulation loop; the airflow driving mechanism, the air inlet, the second cavity, the first cavity, the containing cavity, the third cavity and the air outlet constitute an outer circulation loop. The working condition of the hopper includes an inner circulation mode and an outer circulation mode, the airflow path of the inner circulation mode is the inner circulation loop, and the airflow path of the outer circulation mode includes the inner circulation loop and the outer circulation loop. The hopper further comprises an airflow switching mechanism for switching between the inner circulation mode and the outer circulation mode. The present disclosure realizes the separation and precise control of different working modes of the hopper, and completes the deep drying of the consumables.

Description

Technical Field

[0001] This disclosure relates to the field of 3D printing technology, and in particular to a hopper, a 3D printing feeding device, and a 3D printing equipment. Background Technology

[0002] In the 3D printing process, the moisture content of the printing filaments (such as PLA, ABS, and nylon) is a key factor affecting the quality of the final printed product. When the filaments absorb moisture, the internal moisture rapidly vaporizes during the high-temperature melting process at the print head, leading to uneven filament output, air bubbles, rough model surfaces, poor interlayer bonding, and even nozzle clogging. Therefore, effective drying of the filaments before and during printing is crucial.

[0003] In related technologies, the filament is placed in a sealed container, and a heater and fan create a hot air circulation system to heat the filament. Moisture evaporated from the filament accumulates in the sealed container, causing internal air saturation. This significantly slows down subsequent moisture evaporation, prolonging the drying process and limiting the final drying effect. To address this, some technologies have incorporated air inlets and outlets in the filament compartment to introduce some dry outside air while expelling humid air during heating. However, both heating and dehumidification efficiency are low, failing to meet current printing needs, especially for multi-color printing.

[0004] In multicolor printing, several trolleys are typically placed within the same cartridge housing, with different colors of consumables stored in separate compartments using partitions. However, this approach can result in distinct hot or cold zones within each compartment. Localized overheating can lead to thermal degradation of certain materials; localized underheating can cause increased melt viscosity and poor filament extrusion in some materials, ultimately resulting in quality issues such as interlayer delamination and dimensional deviations. Furthermore, each time a color is switched, the system needs to readjust the cavity temperature, resulting in approximately 15–30% additional heat energy waste during the temperature reset process. The repeated heating-cooling cycle within the closed cavity not only significantly increases overall power consumption but also shortens the lifespan of the heating elements due to heat retention. Utility Model Content

[0005] To overcome the problems existing in related technologies, this specification provides a hopper, a 3D printing feeding device, and a 3D printing equipment, which realizes the separation and precise control of different working modes of the hopper and completes the deep drying of consumables.

[0006] According to a first aspect of this disclosure, a hopper is provided for a 3D printing feeding device, comprising:

[0007] The housing has an air inlet and an air outlet that communicate with the outside.

[0008] A base, disposed within the housing, divides the interior cavity of the housing into at least:

[0009] A receiving cavity for accommodating a tray; and

[0010] airflow cavity;

[0011] The airflow cavity includes:

[0012] The first cavity is connected to the receiving cavity and is equipped with a heating mechanism;

[0013] A second cavity, communicating with the accommodating cavity, the air inlet, and the first cavity, and equipped with an airflow driving mechanism, the airflow driving mechanism being disposed near the heating mechanism; and

[0014] The third cavity is connected to the accommodating cavity and the air outlet;

[0015] The airflow driving mechanism, the first cavity, the second cavity, and the accommodating cavity constitute an internal circulation loop. The airflow driving mechanism is used to pump gas from the second cavity through the first cavity to the accommodating cavity and then back to the second cavity.

[0016] The airflow driving mechanism, the air inlet, the second cavity, the first cavity, the accommodating cavity, the third cavity, and the air outlet constitute an external circulation loop. The airflow driving mechanism is at least used to pump gas from the air inlet through the second cavity, the first cavity, and the accommodating cavity to the third cavity and discharge it from the air outlet.

[0017] The silo operates in two modes: an internal circulation mode and an external circulation mode. The airflow path in the internal circulation mode is an internal circulation loop, and the airflow path in the external circulation mode includes both an internal circulation loop and an external circulation loop.

[0018] The hopper also includes an airflow switching mechanism for switching between the internal circulation mode and the external circulation mode.

[0019] The hopper disclosed herein achieves complete separation and precise control of the two working modes of the hopper through a carefully designed cavity structure and airflow switching mechanism, as detailed below:

[0020] In internal circulation mode, the airflow drive mechanism pumps gas from the second chamber through the first chamber after heating to the receiving chamber, and then back to the second chamber, forming an internal circulation loop. This design allows heat to circulate completely within the hopper, effectively preventing heat loss and achieving efficient energy utilization. In this way, the hopper can quickly and energy-efficiently heat itself and the consumables to the target temperature, significantly accelerating the migration of moisture from the consumables to the surface, creating favorable conditions for subsequent dehumidification operations. During this process, due to the efficient accumulation and recycling of heat, the hopper's heating rate is significantly accelerated, and energy consumption is effectively controlled, resulting in a significant improvement in energy efficiency.

[0021] In external circulation mode, the airflow drive mechanism draws gas from the inlet through the second chamber, the first chamber (heated), and the receiving chamber, pumping it to the third chamber before it exits through the outlet, forming an external circulation loop. At this time, dry outside air is continuously introduced into the hopper, where it mixes and displaces the internal humid air, ensuring the thorough removal of the moisture-rich air. This efficient dehumidification method rapidly reduces humidity within the hopper, overcoming the drying bottlenecks of traditional drying methods and achieving deep drying of consumables. The external circulation mode ensures that moisture within the hopper is removed promptly and effectively, thus guaranteeing the quality and performance of the consumables during the drying process.

[0022] Overall, this hopper provides comprehensive and precise drying control through the organic combination of internal and external circulation modes. In internal circulation mode, it achieves efficient heat accumulation and utilization, rapidly raising the temperature while reducing energy consumption. In external circulation mode, it achieves efficient dehumidification, quickly reducing humidity and ensuring deep drying of the consumables. This design balances heating speed, energy efficiency, and dehumidification efficiency, resulting in overall drying performance far superior to existing single-circuit or hybrid-circuit technologies. This provides strong support for the efficient and stable operation of 3D printing feeding devices, significantly improving print quality and success rate.

[0023] In some exemplary embodiments of this disclosure, the first cavity is located on one side of the second cavity along a first direction, and the third cavity is located on one side of the second cavity along a second direction, wherein the first direction and the second direction intersect.

[0024] In this type of embodiment, by arranging the first cavity, the second cavity, and the third cavity in space along two intersecting directions, a clear and physically isolated airflow channel is provided for the inner and outer circulation loops, effectively avoiding airflow interference or "short circuits" between different loops, and ensuring the reliability of switching between the two working modes and the high efficiency of operation.

[0025] The first cavity and the second cavity are adjacent in the first direction, while the third cavity and the second cavity are adjacent in the second direction, and the two directions intersect. This layout makes the airflow path in the airflow cavity a curved path, which increases the airflow coverage area in the cavity and prolongs the airflow time in the cavity, providing a structural basis for improving the uniformity of the temperature gradient in the silo.

[0026] In some exemplary embodiments of this disclosure, the airflow cavity includes two first cavities, two second cavities, and one third cavity;

[0027] Each of the first cavities is equipped with a heating mechanism, and each of the second cavities is equipped with the airflow driving mechanism.

[0028] In this type of embodiment, the airflow chamber is configured with a structure comprising "two first chambers - two second chambers - a single third chamber," with an independent heating mechanism in each first chamber and an airflow drive mechanism in each second chamber. This allows the hopper to form two parallel airflow channels simultaneously. This design doubles the amount of hot air flowing through the accommodating chamber per unit time, significantly enhancing the hopper's heating power and total airflow. This enables the hopper to simultaneously provide uniform and powerful hot air to multiple trays, greatly improving drying efficiency and processing capacity, meeting the needs of multi-tray systems or applications requiring higher drying speeds.

[0029] In some exemplary embodiments of this disclosure, two second cavities are arranged at intervals along the second direction, and the third cavity is located between the two second cavities.

[0030] In this type of embodiment, two second chambers are arranged at intervals along a second direction, with a third chamber centrally located between them, forming a sandwich layout of "intake-exhaust-intake". In external circulation mode, this structure allows external cold air to enter from the two second chambers on both sides, be heated by their respective first chambers, flow into the receiving cavity, and finally converge and exit through the third chamber. Because intake paths and heating areas are provided on both sides, hot air can be distributed to both the left and right areas of the receiving cavity, resulting in a smaller temperature difference throughout the cavity and significantly suppressing problems such as thermal degradation or under-temperature blockage caused by uneven local temperatures. This layout facilitates uniform airflow distribution across multiple material trays and allows the dehumidification channel to be placed in the center, making the structure more compact and the dehumidification path more rational.

[0031] In some exemplary embodiments of this disclosure, the second direction is perpendicular to the rotation plane of the tray, and the first direction is perpendicular to the second direction and parallel to the rotation plane of the tray.

[0032] In this type of embodiment, by setting the first direction to be perpendicular to the second direction, the first cavity and the third cavity are respectively located in two directions perpendicular to the second cavity. In the internal circulation mode, the receiving cavity is connected to the first cavity and the second cavity. Hot air flows from the first cavity to the receiving cavity and is then drawn back by the second cavity located in the same "first direction". This constitutes a relatively directional circulating flow field along the "first direction". This directional closed loop ensures that the hot air can continuously, stably and directionally "scour" and heat the tray in the receiving cavity. It avoids eddies or dead zones caused by chaotic airflow paths, allowing heat to be efficiently transferred to the consumables, achieving highly controllable and energy-efficient internal circulation heating.

[0033] In external circulation mode, the receiving cavity is connected to the first, second, and third cavities. Hot air enters the receiving cavity from the first cavity, and the humid air, having absorbed moisture, is discharged through the third cavity in the second direction. This layout forcibly establishes a through-flow field within the receiving cavity, extending from the "first direction" to the "second direction" perpendicular to it. The first direction is parallel to the rotation plane of the material tray, while the second direction is perpendicular to it. The airflow is no longer a simple closed loop but forms an open flow channel spanning the entire receiving cavity, from the hot air inlet (where the first cavity connects to the receiving cavity) to the dehumidification outlet (where the receiving cavity connects to the third cavity). Because the dehumidification outlet and the return air outlet (where the receiving cavity connects to the second cavity) are orthogonally separated in direction, the possibility of newly entering hot air entering the receiving cavity entering the dehumidification outlet before fully contacting the consumables is fundamentally eliminated. It forces the airflow to travel a longer distance and cover a wider area before reaching the exhaust port, thereby achieving a complete "replacement" and "purge" of the moisture in the containment cavity.

[0034] This embodiment orthogonally separates the return air path of the internal circulation and the dehumidification path of the external circulation, ensuring that in either mode, the outlet of the other path will not significantly interfere with the current mainstream airflow. This makes the switching between the two circulation modes cleaner and more efficient, further improving their respective operating efficiencies.

[0035] In some exemplary embodiments of this disclosure, the two second cavities are arranged symmetrically about a first plane, which is parallel to the rotation plane of the tray and passes through the central axis of the receiving cavity.

[0036] In this type of embodiment, the axisymmetric layout makes the overall structure of the hopper more stable. The symmetrical cavity design provides better balance and stability. Moreover, the symmetrical structure facilitates manufacturing and assembly, reduces production costs, simplifies mold design and processing, reduces manufacturing errors, and improves product quality and consistency.

[0037] Secondly, the two second cavities are arranged symmetrically about the first plane, and the first plane is parallel to the rotation plane of the material tray and passes through the central axis of the receiving cavity. This symmetrical layout allows the airflow to enter the receiving cavity evenly from both sides, providing a consistent drying environment for multiple material trays side by side. This fundamentally ensures the uniformity of drying of all material trays in the receiving cavity and avoids drying differences caused by different positions.

[0038] In some exemplary embodiments of this disclosure, the orthographic projection area of ​​the first cavity on the bottom wall of the housing is greater than the orthographic projection area of ​​the second cavity on the bottom wall of the housing.

[0039] In this type of embodiment, making the projected area of ​​the first cavity (heating cavity) larger than that of the second cavity (return air cavity) means that, with a fixed total air volume, the air velocity in the more spacious heating cavity will decrease. The lower velocity prolongs the contact time between the air and the heating mechanism, resulting in more thorough heat exchange, thereby improving heating efficiency and making the outlet hot air temperature more stable.

[0040] In some exemplary embodiments of this disclosure, the airflow switching mechanism includes a first airflow switching mechanism disposed at the communication point between the third cavity and the receiving cavity, for controlling the connection or blockage between the third cavity and the receiving cavity; and

[0041] A second airflow switching mechanism is provided at the air inlet to control whether the airflow cavity is connected to or blocked from the outside.

[0042] In this type of embodiment, by setting a first airflow switching mechanism and a second airflow switching mechanism, two independent airflow switching mechanisms control the dehumidification channel and the air inlet respectively, achieving more precise and diversified control of the airflow circuit. In addition to switching between internal circulation mode and external circulation mode, it can also realize a variety of intermediate or special modes such as "internal circulation + micro-air replenishment" and "forced ventilation", greatly enhancing the functional adaptability and control flexibility of the equipment.

[0043] In some exemplary embodiments of this disclosure, a plurality of first through holes are provided on the cavity wall between the receiving cavity and the first cavity, and the receiving cavity communicates with the first cavity through the first through holes;

[0044] The cavity wall between the receiving cavity and the second cavity is provided with a plurality of second through holes, and the receiving cavity communicates with the second cavity through the second through holes;

[0045] The cavity wall between the accommodating cavity and the third cavity is provided with a plurality of third through holes, and the accommodating cavity communicates with the third cavity through the third through holes.

[0046] In this type of embodiment, the communication between cavities is specifically implemented through multiple through holes, which is a simple, low-cost, and easy-to-manufacture method. At the same time, the arrangement of multiple through holes helps to disperse the concentrated airflow into multiple streams, making the airflow distribution entering or leaving the accommodating cavity more uniform and avoiding the problem of excessively strong or weak airflow in local areas.

[0047] In some exemplary embodiments of this disclosure, the first through hole is provided on the cavity wall between the receiving cavity and the first cavity body, away from the second cavity body.

[0048] In this type of embodiment, in the internal circulation mode, the heated gas passes through the first cavity and the first through-hole before entering the receiving cavity, and then through the second through-hole into the second cavity. In this flow path, the first through-hole (hot air inlet) is positioned far from the second cavity (return air outlet), forcibly lengthening the circulation path of the hot air within the receiving cavity. This ensures that the hot air must pass through most of the receiving space before being drawn away, minimizing the possibility of airflow taking shortcuts, thereby significantly improving heat utilization and circulation effectiveness.

[0049] In some exemplary embodiments of this disclosure, the total maximum ventilation volume S1 of the plurality of first through holes, the total maximum ventilation volume S2 of the plurality of second through holes, and the total maximum ventilation volume S3 of the plurality of third through holes satisfy S1≥S2>S3.

[0050] In this type of embodiment, S1≥S2 (total maximum ventilation volume of the first through-hole ≥ total maximum ventilation volume of the second through-hole) ensures that in the internal circulation mode, the airflow drive mechanism pumps the gas from the second cavity to the first cavity (heating zone), and then enters the receiving cavity at high speed through the first through-hole, allowing the hot airflow to fully cover the tray. Since the total maximum ventilation volume of the second through-hole is less than or equal to the total maximum ventilation volume of the first through-hole, the airflow velocity returning to the second cavity is moderate, avoiding a sudden drop in internal pressure due to excessively fast return, thereby maintaining a stable internal circulation airflow and improving the heating uniformity of the tray. S2>S3 (total maximum ventilation volume of the second through-hole > total maximum ventilation volume of the third through-hole) ensures that in the external circulation mode, the airflow drive mechanism mixes the fresh air from the air inlet with part of the circulating air from the second cavity and sends it into the first cavity for heating, and then enters the receiving cavity through the first through-hole. Since the ventilation volume of the third through-hole is the smallest, most of the airflow is forced to remain in the receiving cavity for a sufficient period of time, extending the heat exchange time and preventing the airflow from being quickly discharged without effective heating, thereby improving the thermal energy utilization efficiency.

[0051] That is, the S1≥S2>S3 ratio design ensures that: in internal circulation mode, the airflow preferentially returns to the second cavity through the second through-hole, forming a closed loop; in external circulation mode, the airflow is automatically discharged along a preset path (accommodation cavity → third cavity → air outlet) due to the flow restriction effect of the third through-hole, without the need for additional valve control, simplifying the design of the airflow switching mechanism. S1≥S2 avoids the formation of vortices or local low-pressure areas in the accommodation cavity during internal circulation; S2>S3 ensures that the airflow direction is controllable during external circulation, avoiding mutual interference between the airflow at the air inlet and outlet, and maintaining system pressure balance.

[0052] In some exemplary embodiments of this disclosure, the cavity wall between the receiving cavity and the airflow cavity includes an arcuate wall for supporting the tray, and a connecting wall connecting the arcuate wall and the side wall of the housing;

[0053] The curvature of the arc-shaped wall is consistent with the curvature of the outer periphery of the tray, and the connecting wall is bent.

[0054] In this type of embodiment, the cavity wall between the receiving cavity and the airflow cavity includes an arc-shaped wall and a connecting wall. The curvature of the arc-shaped wall matches the curvature of the outer periphery of the tray, and the connecting wall is bent. This structural design can better support the tray and ensure its stable placement within the receiving cavity. The arc-shaped wall, matching the curvature of the tray's outer periphery, provides better support and stability, reducing tray swaying and displacement during feeding; while the bent connecting wall increases the strength and stability of the cavity wall. More importantly, using an arc-shaped wall adapted to the tray's shape minimizes the ineffective space between the tray and the cavity wall, allowing airflow to flow more closely to the tray surface, reducing dead air angles, and enhancing the direct heat exchange effect on the consumables.

[0055] In some exemplary embodiments of this disclosure, the first through hole is located at the end of the arc-shaped wall away from the connecting wall, and the second through hole and the third through hole are located on the connecting wall.

[0056] In this type of embodiment, in internal circulation mode, the heated gas passes through the first cavity and the first through-hole before entering the receiving cavity, and then through the second through-hole into the second cavity. In external circulation mode, the heated gas passes through the first cavity and the first through-hole before entering the receiving cavity, and then through the second through-hole into the second cavity, while simultaneously being discharged through the third through-hole, the third cavity, and the air outlet. In this flow path, in this embodiment, the first through-hole (hot air inlet) is located on the arc-shaped wall, while the second and third through-holes (return air or dehumidification outlets) are located on the connecting wall, further clarifying and separating the positions of the inlet and outlet airflows structurally. Hot air is blown directly onto the consumables from the lower arc-shaped wall, while the returning air is drawn away from the upper side connecting wall, forming a more rational "bottom-in, top-out" circulation, improving the efficiency of airflow organization.

[0057] In some exemplary embodiments of this disclosure, the shortest distance L1 between the orthographic projection of the plurality of first through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, the shortest distance L2 between the orthographic projection of the plurality of second through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, and the shortest distance L3 between the orthographic projection of the plurality of third through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, satisfies L1 < L2 < L3.

[0058] In this type of embodiment, by specifically designing the shortest distances L1, L2, and L3 between the orthographic projections of multiple first through holes, second through holes, and third through holes on the bottom wall of the housing and the orthographic projection of the material tray rotation axis on the bottom wall of the housing, so that they satisfy the relationship L1 < L2 < L3, the airflow organization in the accommodating cavity can be optimized, thereby significantly improving the uniformity and efficiency of heating and drying 3D printing consumables on the material tray in different working modes.

[0059] In internal circulation mode, the airflow is pumped by the airflow drive mechanism, heated by the heating mechanism in the first chamber, and then mainly enters the receiving chamber through the first through-hole at the shortest distance L1. Since L1 is the smallest, this means that the inlet of the hot airflow is closest to the central axis area of ​​the tray. At the same time, the airflow mainly flows back to the second chamber through the second through-hole at a distance L2. Since L1 < L2, the hot airflow enters from a position close to the center of the tray, then diffuses outward and flows out from a relatively outer position, forming a circulating airflow path from the inside out, covering the entire radial direction of the tray. This "center in, circumferential out" airflow organization method can ensure that heat is evenly delivered to all areas of the tray, effectively avoiding the problems of insufficient or excessive heating in the central or edge areas that may occur in traditional designs, thereby significantly improving the uniformity of drying and preheating of consumables on the entire tray.

[0060] When switching to external circulation mode to expel internal moisture, the airflow path includes discharge from the third chamber through the outlet. The position of the third through-hole is defined by L3, and L3 is the largest (L1 < L2 < L3). This means that the moisture exhaust outlet (third through-hole) is located at the position farthest from the rotating axis of the material tray, i.e., closest to the edge of the receiving cavity. During airflow circulation, the gas carrying moisture from the consumables, after reaching the edge area of ​​the receiving cavity, can be captured and discharged most directly and efficiently through these outermost third through-holes. This design avoids moisture from lingering in the receiving cavity for a long time or forming circulation dead zones, ensuring that the moisture can be smoothly discharged after following the longest possible path, thereby greatly improving the overall moisture exhaust efficiency and deep drying capacity of the hopper.

[0061] By ensuring L1 < L2 < L3, the forced hot air must enter from the bottom or center of the tray, then disperse upwards and outwards before being drawn away from the outer perimeter of the tray. This "center in, perimeter out" airflow pattern ensures that the airflow must pass through or fully contact the consumable rolls on the tray, greatly improving the penetration and uniformity of drying.

[0062] Furthermore, this design ensures effective gas exchange between the second and third chambers and the external environment of the silo. The placement of the second and third through-holes allows for smoother airflow as it enters and exits the silo, reducing airflow resistance.

[0063] In some exemplary embodiments of this disclosure, the distance between the second through hole and the bottom wall of the housing, and the distance between the third through hole and the bottom wall of the housing, are both greater than the distance between the first through hole and the bottom wall of the housing;

[0064] The distance between the second through hole and the bottom wall of the housing, and the distance between the third through hole and the bottom wall of the housing, are both less than or equal to half the height of the housing.

[0065] In this type of embodiment, by setting the height of the second and third through-holes (return air or exhaust vents) significantly higher than the first through-hole (hot air inlet), the physical law of hot air's low density and natural upward movement is cleverly utilized. Hot air enters from a lower position, heats the consumables, and absorbs moisture. The "waste heat air" carrying moisture naturally gathers at the top of the accommodating cavity. At this point, setting the return air or exhaust vent at a higher position greatly improves the efficiency of removing hot and humid air. This allows the entire circulation process to combine the advantages of forced convection and natural convection, further enhancing drying efficiency and energy-saving effects.

[0066] According to a second aspect of this disclosure, a 3D printing feeding device is provided, including a material tray and a hopper as described in the first aspect, the material tray being located in the receiving cavity.

[0067] According to a third aspect of this disclosure, a 3D printing apparatus is provided, including a 3D printer and a 3D printing feed device as described in the second aspect, the 3D printing feed device being used to supply consumables to the 3D printer.

[0068] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this specification. Attached Figure Description

[0069] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this specification and, together with the description, serve to explain the principles of this specification.

[0070] Figure 1This is a schematic cross-sectional view of the side of the silo in an exemplary embodiment of this disclosure.

[0071] Figure 2 This is a bottom view of the silo in an exemplary embodiment of this disclosure.

[0072] Figure 3 This is a bottom view schematic diagram of the location distribution of the airflow chambers in the hopper in an exemplary embodiment of this disclosure.

[0073] Figure 4 This is a schematic diagram of the three-dimensional structure of the silo in an exemplary embodiment of this disclosure.

[0074] Figure 5 This is a top view of the silo in an exemplary embodiment of this disclosure.

[0075] Figure 6 This is a schematic diagram of the air outlet structure of the silo in an exemplary embodiment of this disclosure.

[0076] Figure 7 This is a schematic diagram showing the height distribution of the first and second through holes in the hopper in an exemplary embodiment of this disclosure.

[0077] Figure 8 This is a schematic diagram of gas flow in the internal circulation mode of the silo in an exemplary embodiment of this disclosure.

[0078] Figure 9 This is a schematic diagram of gas flow in the external circulation mode of the silo in an exemplary embodiment of this disclosure.

[0079] Figure 10 This is a schematic diagram showing the positional relationship between the first through hole, the second through hole, and the third through hole in an exemplary embodiment of this disclosure.

[0080] Explanation of reference numerals in the attached figures

[0081] 100 - Shell; 110 - Drying and dehumidification zone; 120 - Non-drying zone; 200 - Base; 201 - Cavity wall between the accommodating cavity and the airflow cavity; 2011 - Arc-shaped wall; 2012 - Connecting wall; 12a - First connecting wall; 12b - Second connecting wall; 300 - Accommodating cavity; 400 - Airflow cavity; 410 - First cavity; 420 - Second cavity; 421 - Air inlet; 430 - Third cavity; 431 - Air outlet; 500 - Airflow drive mechanism; 600 - Heating mechanism; 700 - Airflow switching mechanism; 710 - First reversing valve; 720 - Second reversing valve; 730 - Third reversing valve; 810 - First through hole; 820 - Second through hole; 830 - Third through hole; Y - First direction; X - Second direction; 10 - First plane; 910 - First cavity; 920 - Second cavity. Detailed Implementation

[0082] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0083] Although relative terms such as "up" and "down" are used in this specification to describe the relative relationship of one component of an icon to another, these terms are used only for convenience, such as according to the orientation of the examples shown in the accompanying drawings. It is understood that if the device of the icon is flipped upside down, the component described as "up" will become the component described as "down." When a structure is "up" of another structure, it may mean that the structure is integrally formed on the other structure, or that the structure is "directly" mounted on the other structure, or that the structure is "indirectly" mounted on the other structure through another structure.

[0084] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0085] In this disclosure, terms such as "perpendicular" and "equal" refer to perpendicularity and equality within the range of process error, not absolute perpendicularity and equality. Process error can be within ±10% or ±5%. For example, if the first direction and the second direction are perpendicular, it can be understood that the angle between the first direction and the second direction can be 90° ± 5°.

[0086] In related technologies, a hopper for a 3D printing feeding device is provided. The hopper includes a shell, a base, a fan, and a heating element. The base is housed within the shell and has a base area. A material tray is placed in the base area. An airflow cavity is formed between the base and the bottom wall of the shell. The base has a first air hole and a second air hole, which are spaced apart circumferentially on the material tray. The first and second air holes respectively connect to the base area and the airflow cavity. The fan and heating element are housed within the airflow cavity. The fan is positioned adjacent to the first air hole, and its outlet faces the second air hole. In this design, the drying and dehumidification effect of the hopper is not ideal, resulting in print quality that fails to meet user requirements.

[0087] Based on this, such as Figures 1 to 4 , Figure 6 As shown, this embodiment of the present disclosure provides a hopper for a 3D printing feeding device. The hopper includes a housing 100 and a base 200. The housing 100 has an air inlet 421 and an air outlet 431 communicating with the outside. The base 200 is disposed inside the housing 100, and the base 200 divides the inner cavity of the housing 100 into at least a receiving cavity 300 for accommodating the material tray and an airflow cavity 400. The airflow cavity 400 includes a first cavity 410, a second cavity 420, and a third cavity 430. The first cavity 410 communicates with the receiving cavity 300 and is provided with a heating mechanism 600. The second cavity 420 communicates with the receiving cavity 300, the air inlet 421, and the first cavity 410, and is provided with an airflow driving mechanism 500, which is disposed close to the heating mechanism 600. The third cavity 430 communicates with the receiving cavity 300 and the air outlet 431.

[0088] The airflow drive mechanism 500, the first cavity 410, the second cavity 420 and the accommodating cavity 300 constitute an internal circulation loop. The airflow drive mechanism 500 is used to pump gas from the second cavity 420 through the first cavity 410 to the accommodating cavity 300 and then back to the second cavity 420.

[0089] The airflow drive mechanism 500, the air inlet 421, the second cavity 420, the first cavity 410, the accommodating cavity 300, the third cavity 430 and the air outlet 431 constitute an external circulation loop. The airflow drive mechanism 500 is at least used to pump gas from the air inlet 421 through the second cavity 420, the first cavity 410 and the accommodating cavity 300 to the third cavity 430 and then discharge it from the air outlet 431.

[0090] The hopper operates in two modes: internal circulation and external circulation. In internal circulation mode, the airflow path is an internal circulation loop, while in external circulation mode, the airflow path includes both an internal circulation loop and an external circulation loop. The hopper also includes an airflow switching mechanism 700 for switching between internal and external circulation modes.

[0091] The hopper disclosed herein achieves complete separation and precise control of the two working modes of the hopper through a carefully designed cavity structure and airflow switching mechanism, as detailed below:

[0092] In internal circulation mode, the airflow drive mechanism 500 pumps gas from the second chamber 420 through the first chamber 410 to the receiving chamber 300 and then back to the second chamber 420, forming an internal circulation loop. This design allows heat to circulate completely within the hopper, effectively preventing heat loss and achieving efficient energy utilization. In this way, the hopper can quickly and energy-efficiently heat itself and the consumables to the target temperature, greatly accelerating the migration of moisture from the consumables to the surface, creating favorable conditions for subsequent dehumidification operations. During this process, due to the efficient accumulation and recycling of heat, the hopper's heating rate is significantly accelerated, and energy consumption is effectively controlled, resulting in a significant improvement in energy utilization efficiency.

[0093] In external circulation mode, the airflow drive mechanism 500 pumps gas from the air inlet 421 through the second chamber 420, the first chamber 410, and the accommodating chamber 300 to the third chamber 430 and then discharges it from the air outlet 431, forming an external circulation loop. At this time, dry outside air is continuously introduced into the hopper, where it mixes and displaces the internal humid air, allowing the moisture-rich, hot air to be thoroughly discharged. This efficient dehumidification method can quickly reduce the humidity inside the hopper, breaking through the drying bottleneck present in traditional drying methods and achieving deep drying of consumables. The external circulation mode ensures that moisture inside the hopper can be discharged in a timely and effective manner, thereby guaranteeing the quality and performance of consumables during the drying process.

[0094] Overall, this hopper provides comprehensive and precise drying control through the organic combination of internal and external circulation modes. In internal circulation mode, it achieves efficient heat accumulation and utilization, rapidly raising the temperature while reducing energy consumption. In external circulation mode, it achieves efficient dehumidification, quickly reducing humidity and ensuring deep drying of the consumables. This design balances heating speed, energy efficiency, and dehumidification efficiency, resulting in overall drying performance far superior to existing single-circuit or hybrid-circuit technologies. This provides strong support for the efficient and stable operation of 3D printing feeding devices, significantly improving print quality and success rate.

[0095] The various parts of the hopper provided in the embodiments of this disclosure will now be described in detail with reference to the accompanying drawings:

[0096] like Figure 1 and Figure 4 As shown, the housing 100 has a hollow structure. The internal cavity of the housing 100 can be adaptively divided and shaped according to the shape, size, and assembly relationship of the components to be arranged, or it can be a single, continuous space. This disclosure does not limit this. The housing 100 can be a cuboid, cube, cylinder, or irregular three-dimensional structure, but is not limited thereto. In the exemplary embodiment of this disclosure, the housing 100 is generally a cuboid structure.

[0097] The housing 100 is provided with an air inlet 421 and an air outlet 431 that communicate with the outside. Outside air can enter the hopper through the air inlet 421 and participate in gas circulation. The air inside the hopper can be discharged through the air outlet 431. In some exemplary embodiments of this disclosure, the air inlet 421 is located on the bottom wall of the housing 100, and the air outlet 431 is located on the side wall of the housing 100. Defining the positions of the air inlet 421 and the air outlet 431 can optimize the airflow path. The air outlet 431 of the third cavity 430 is located on the side wall of the housing 100, which is on a different shell wall than the air inlet 421 of the second cavity 420, thus preventing airflow interference between the two.

[0098] A base 200 is disposed within the housing 100. The base 200 divides the interior of the housing 100 into at least a receiving cavity 300 and an airflow cavity 400. The base 200 may generally be a support comprising multiple plate structures. The receiving cavity 300 may be located above the airflow cavity 400 and is used to receive a tray. The shape of the receiving cavity 300 may be set according to the shape of the tray. Multiple trays may be placed within the receiving cavity 300. Optionally, the receiving cavity 300 may include at least one tray unit, each tray unit comprising multiple tray areas, and one tray area may hold one tray. Exemplarily, the receiving cavity 300 includes a tray unit, each tray unit comprising at least two tray areas. The tray areas within a single tray unit are interconnected.

[0099] It should be noted that, in addition to the accommodating cavity 300 and the airflow cavity 400, the inner cavity of the housing 100 may also include other cavities. For example, the accommodating cavity 300 is located above the airflow cavity 400, i.e., on the side away from the bottom wall of the housing 100. The inner cavity of the housing 100 also includes a first cavity 910 located between the airflow cavity 400 and the bottom wall of the housing 100, and may further include a second cavity 920 located between the airflow cavity 400 and the side wall of the housing 100. The first cavity 910 and the second cavity 920 can be used to accommodate structural components, and this disclosure does not limit their use.

[0100] For example, the cavity wall 201 between the receiving cavity 300 and the airflow cavity 400 includes an arc-shaped wall 2011 for supporting the tray, and a connecting wall 2012 connecting the arc-shaped wall 2011 and the side wall of the housing 100. The curvature of the arc-shaped wall 2011 matches the curvature of the outer periphery of the tray, and the connecting wall 2012 is bent. The tray is generally a disc structure, and correspondingly, the portion of the receiving cavity 300 used to support the tray is also configured as an arc-shaped structure, i.e., the arc-shaped wall 2011. This arc-shaped wall 2011 can be approximately an arc-shaped structure smaller than a semicircle.

[0101] Optionally, the connecting wall 2012 may extend substantially to the middle height region of the side wall of the housing 100. The connecting wall 2012 is bent, with its bending direction generally toward the bottom wall of the housing 100, but not limited thereto. Exemplarily, the connecting wall 2012 includes a first connecting wall 12a and a second connecting wall 12b that are interconnected, wherein the first connecting wall 12a may be formed by one end of the arcuate wall 2011 extending toward the top wall and side wall of the housing 100. The first connecting wall 12a may be an arcuate wall with a certain curvature or a planar wall. The second connecting wall 12b connects the first connecting wall 12a and the side wall, and the second connecting wall 12b is generally a planar wall, and the second connecting wall 12b is generally parallel to the bottom wall of the housing 100, but not limited thereto.

[0102] In this type of embodiment, the cavity wall 201 between the receiving cavity 300 and the airflow cavity 400 includes an arc-shaped wall 2011 and a connecting wall 2012. The curvature of the arc-shaped wall 2011 matches the curvature of the outer periphery of the tray, and the connecting wall 2012 is bent. This structural design can better support the tray and ensure its stable placement within the receiving cavity 300. The arc-shaped wall 2011, matching the curvature of the outer periphery of the tray, provides better support and stability, reducing the tray's shaking and displacement during feeding; while the bent connecting wall 2012 increases the strength and stability of the cavity wall 201.

[0103] like Figure 1 and Figure 3 As shown, the airflow cavity 400 is located below the receiving cavity 300. The airflow cavity 400 includes a first cavity 410, a second cavity 420, and a third cavity 430. The first cavity 410 communicates with the receiving cavity 300 and is equipped with a heating mechanism 600. The second cavity 420 communicates with the receiving cavity 300, the air inlet 421, and the first cavity 410, and is equipped with an airflow driving mechanism 500, which is located close to the heating mechanism 600. The third cavity 430 communicates with the receiving cavity 300 and the air outlet 431.

[0104] Gas flow between the first cavity 410 and the second cavity 420 is achieved through the airflow drive mechanism 500. The second cavity 420 and the third cavity 430 are independent of each other and are not connected. The airflow drive mechanism 500, the first cavity 410, the second cavity 420, and the accommodating cavity 300 constitute an internal circulation loop, wherein the airflow drive mechanism 500 is used to pump gas from the second cavity 420 through the first cavity 410 to the accommodating cavity 300 and then back to the second cavity 420. The airflow drive mechanism 500, the air inlet 421, the second cavity 420, the first cavity 410, the accommodating cavity 300, the third cavity 430, and the air outlet 431 constitute an external circulation loop, wherein the airflow drive mechanism 500 is at least used to pump gas from the air inlet 421 through the second cavity 420, the first cavity 410, and the accommodating cavity 300 to the third cavity 430 and then discharge it from the air outlet 431.

[0105] The hopper operates in two modes: internal circulation and external circulation. In internal circulation mode, the airflow path is an internal circulation loop, while in external circulation mode, the airflow path includes both an internal circulation loop and an external circulation loop. The hopper also includes an airflow switching mechanism 700 for switching between internal and external circulation modes.

[0106] Optionally, the first cavity 410 is located on one side of the second cavity 420 along the first direction Y, and the third cavity 430 is located on one side of the second cavity 420 along the second direction X, wherein the first direction Y and the second direction X intersect. The included angle between the first direction Y and the second direction X can be from 60° to 120°, such as 60°, 70°, 80°, 90°, 100°, 110° or 120°, but is not limited thereto. Preferably, the first direction Y and the second direction X are perpendicular.

[0107] By spatially arranging the first cavity 410, the second cavity 420, and the third cavity 430 along two intersecting directions (the first direction Y and the second direction X), the hopper of this disclosure provides a clearly structured and physically isolated airflow channel for the internal and external circulation loops. This layout effectively avoids airflow interference or "short circuit" phenomena between different loops, ensuring the reliability of switching between the two operating modes and the high efficiency of operation.

[0108] The airflow driving mechanism 500 is used to drive gas flow, specifically to drive external gas into the second cavity 420, and to drive gas flow between the second cavity 420 and the first cavity 410, such as driving gas in the second cavity 420 to flow into the first cavity 410. The heating mechanism 600 can be disposed at the air outlet of the airflow driving mechanism 500.

[0109] The heating mechanism 600 can be a ceramic heating rod, which uses the heat generated when energized to uniformly heat the gas; or it can be a PTC (Positive Temperature Coefficient) heating element, which has automatic temperature control characteristics and can automatically adjust the heating power according to changes in ambient temperature to ensure the stability and consistency of the gas temperature. The airflow driving mechanism 500 can be a vortex fan or a small air pump, etc. Taking a vortex fan as an example, it generates a powerful airflow through high-speed rotation, which can quickly push the gas to the first cavity 410, the receiving cavity 300, or other designated areas.

[0110] Optionally, such as Figure 3 As shown in the figure, the walls of the first cavity 410 and the second cavity 420 are not directly visible. Therefore, the distribution of the first cavity 410 and the second cavity 420 is roughly indicated by dashed boxes. The airflow cavity 400 includes two first cavities 410, two second cavities 420, and one third cavity 430. Each first cavity 410 is equipped with a heating mechanism 600, and each second cavity 420 is equipped with an airflow driving mechanism 500.

[0111] In this type of embodiment, the airflow chamber 400 is configured with a structure comprising "two first chambers 410, two second chambers 420, and a single third chamber 430," with a heating mechanism 600 independently configured in each first chamber 410 and an airflow drive mechanism 500 configured in each second chamber 420. Thus, the hopper can form two parallel airflow channels simultaneously. This design doubles the amount of hot air flowing through the receiving chamber 300 per unit time, significantly enhancing the heating power and total airflow of the hopper. This allows the hopper to simultaneously provide uniform and powerful hot air to multiple trays, greatly improving drying efficiency and processing capacity, meeting the needs of multi-tray systems or applications requiring higher drying speeds.

[0112] Furthermore, the two second cavities 420 are arranged at intervals along the second direction X, and the third cavity 430 is located between the two second cavities 420.

[0113] In this type of embodiment, two second cavities 420 are arranged at intervals along the second direction X, and a third cavity 430 is centrally placed between them, forming a sandwich layout of "intake-exhaust-intake". In the external circulation mode, external cold air (the temperature of which can be room temperature or below room temperature relative to the hot air generated by heating inside the hopper) enters from the two second cavities 420, is heated by their respective first cavities 410, flows into the receiving cavity 300, and finally converges and is discharged through the third cavity 430. Since air intake paths and heating areas are provided on both sides, hot air can be distributed in both left and right areas of the receiving cavity 300, thereby reducing the temperature difference within the entire cavity and significantly suppressing problems such as thermal degradation or under-temperature blockage caused by uneven local temperature.

[0114] Optionally, the second direction X is perpendicular to the rotation plane of the tray, and the first direction Y is perpendicular to the second direction X and parallel to the rotation plane of the tray.

[0115] By setting the first direction Y to be perpendicular to the second direction X, the first cavity 410 and the third cavity 430 are respectively located in two directions perpendicular to the second cavity 420. In the internal circulation mode, the accommodating cavity 300 is connected to the first cavity 410 and the second cavity 420. Hot air flows from the first cavity 410 to the accommodating cavity 300 and is then drawn back by the second cavity 420, which is located in the same "first direction Y". This constitutes a relatively directional circulating flow field along the "first direction Y". This directional closed loop ensures that the hot air can continuously, stably and directionally "scour" and heat the tray in the accommodating cavity 300. It avoids eddies or dead zones caused by chaotic airflow paths, allowing heat to be efficiently transferred to consumables, achieving highly controllable and energy-efficient internal circulation heating.

[0116] In external circulation mode, the receiving cavity 300 is connected to the first cavity 410, the second cavity 420, and the third cavity 430. Hot air enters the receiving cavity 300 from the first cavity 410, and the humid air, having absorbed moisture, is discharged through the third cavity 430 in the second direction X. This layout forcibly establishes a through-flow field within the receiving cavity 300, extending from the "first direction Y" to the "second direction X," which is perpendicular to the "first direction Y." The first direction Y is parallel to the rotation plane of the material tray, and the second direction X is perpendicular to the rotation plane of the material tray. The airflow is no longer a simple closed loop but forms an open flow channel spanning the entire receiving cavity 300, from the hot air inlet (where the first cavity 410 connects to the receiving cavity 300) to the dehumidification outlet (where the receiving cavity 300 connects to the third cavity 430). Because the exhaust vent and return air vent (where the accommodating cavity 300 connects to the second cavity 420) are orthogonally separated in direction, the possibility of newly entering hot air from the accommodating cavity 300 entering the exhaust vent before fully contacting the consumables is fundamentally eliminated. This forces the airflow to travel a longer distance and cover a wider area before reaching the exhaust vent, thus achieving a complete "replacement" and "purge" of moisture within the accommodating cavity 300.

[0117] This embodiment orthogonally separates the return air path of the internal circulation and the dehumidification path of the external circulation, ensuring that in either mode, the outlet of the other path will not significantly interfere with the current mainstream airflow. This makes the switching between the two circulation modes cleaner and more efficient, further improving their respective operating efficiencies.

[0118] Preferably, such as Figure 4As shown, the two second cavities 420 are arranged symmetrically about the first plane 10, which is parallel to the rotation plane of the tray and passes through the central axis of the receiving cavity 300.

[0119] In this type of embodiment, the axisymmetric layout makes the overall structure of the hopper more stable. The symmetrical cavity design provides better balance and stability. Moreover, the symmetrical structure facilitates manufacturing and assembly, reduces production costs, simplifies mold design and processing, reduces manufacturing errors, and improves product quality and consistency.

[0120] Secondly, the two second cavities 420 are arranged symmetrically about the first plane 10, and the first plane 10 is parallel to the rotation plane of the tray and passes through the central axis of the receiving cavity 300. This symmetrical layout allows the airflow to enter the receiving cavity 300 evenly from both sides, providing a consistent drying environment for multiple trays arranged side by side. This fundamentally ensures the uniformity of drying of all trays in the receiving cavity 300 and avoids drying differences caused by different positions.

[0121] like Figure 1 and Figure 3 As shown, the projected area of ​​the first cavity 410 on the bottom wall of the housing 100 is greater than the projected area of ​​the second cavity 420 on the bottom wall of the housing 100.

[0122] In this type of embodiment, making the projected area of ​​the first cavity (heating cavity) larger than that of the second cavity (return air cavity) means that, with a fixed total air volume, the air velocity in the more spacious heating cavity will decrease. The lower velocity prolongs the contact time between the air and the heating mechanism, resulting in more thorough heat exchange, thereby improving heating efficiency and making the outlet hot air temperature more stable.

[0123] Optionally, such as Figure 1 , Figure 4 and Figure 5As shown, each cavity of the airflow cavity 400 can communicate with the receiving cavity 300 through through holes. Exemplarily, a plurality of first through holes 810 are provided on the cavity wall between the receiving cavity 300 and the first cavity 410, and the receiving cavity 300 communicates with the first cavity 410 through the first through holes 810. The plurality of first through holes 810 are arranged in an array, and adjacent rows or columns of first through holes 810 are staggered. A plurality of second through holes 820 are provided on the cavity wall between the receiving cavity 300 and the second cavity 420, and the receiving cavity 300 communicates with the second cavity 420 through the second through holes 820. The plurality of second through holes 820 are arranged in an array, and adjacent rows or columns of second through holes 820 are staggered. A plurality of third through holes 830 are provided on the cavity wall between the receiving cavity 300 and the third cavity 430, and the receiving cavity 300 communicates with the third cavity 430 through the third through holes 830. Multiple third through holes 830 are arranged in an array, with adjacent rows or columns of third through holes 830 staggered. The first through hole 810, the second through hole 820, and the third through hole 830 can be circular holes, square holes, or other regular polygonal holes, but are not limited thereto. For example, the first through hole 810, the second through hole 820, and the third through hole 830 are circular holes.

[0124] In this type of embodiment, the communication between cavities is specifically implemented through multiple through holes, which is a simple, low-cost, and easy-to-manufacture method. At the same time, the arrangement of multiple through holes helps to disperse the concentrated airflow into multiple streams, making the airflow distribution entering or leaving the accommodating cavity more uniform and avoiding the problem of excessively strong or weak airflow in local areas.

[0125] Optionally, the total maximum ventilation volume S1 of the plurality of first through holes 810, the total maximum ventilation volume S2 of the plurality of second through holes 820, and the total maximum ventilation volume S3 of the plurality of third through holes 830 satisfy S1≥S2>S3. For example, when the through hole sizes of the first through holes 810, the second through holes 820, and the third through holes 830 are approximately equal, the number of first through holes 810 is greater than the number of second through holes 820, and the number of second through holes 820 is greater than the number of third through holes 830.

[0126] In this type of embodiment, S1≥S2 (the total maximum ventilation volume of the first through hole 810 ≥ the total maximum ventilation volume of the second through hole 820) ensures that in the internal circulation mode, the airflow drive mechanism 500 pumps the gas from the second cavity 420 to the first cavity 410 (heating zone), and then enters the receiving cavity 300 at high speed through the first through hole 810, so that the hot airflow fully covers the material tray. Since the total maximum ventilation volume of the second through hole 820 is less than or equal to the total maximum ventilation volume of the first through hole 810, the airflow speed returning to the second cavity 420 is moderate, avoiding a sudden drop in internal pressure in the receiving cavity 300 due to excessively fast return, thereby maintaining a stable internal circulation airflow and improving the heating uniformity of the material tray.

[0127] S2 > S3 (the total maximum ventilation volume of the second through-hole 820 > the total maximum ventilation volume of the third through-hole 830) ensures that in the external circulation mode, the airflow drive mechanism 500 mixes the fresh air from the air inlet 421 with part of the circulating air from the second cavity 420 and sends it into the first cavity 410 for heating, and then enters the accommodating cavity 300 through the first through-hole 810. Since the ventilation volume of the third through-hole 830 is the smallest, most of the airflow is forced to stay in the accommodating cavity 300 for a sufficient period of time, prolonging the heat exchange time and preventing the airflow from being quickly discharged without effective heating, thereby improving the thermal energy utilization efficiency.

[0128] That is, the design ratio of S1≥S2>S3 ensures that: in the internal circulation mode, the airflow preferentially returns to the second cavity 420 through the second through hole 820, forming a closed loop; in the external circulation mode, the airflow is automatically discharged along the preset path (accommodation cavity 300→third cavity 430→outlet 431) due to the flow restriction effect of the third through hole 830, without the need for additional valve regulation, simplifying the design of the airflow switching mechanism 700. S1≥S2 avoids the formation of vortices or local low-pressure areas in the accommodation cavity 300 during internal circulation; S2>S3 ensures that the airflow direction is controllable during external circulation, avoiding mutual interference between the airflow at the inlet 421 and the outlet 431, and maintaining the system pressure balance.

[0129] For example, S1:S2:S3≈(10-12):10:(1-3). For instance, S1:S2:S3≈10:10:1; S1:S2:S3≈11:10:1; S1:S2:S3≈12:10:3, but not limited to these. Preferably, S1:S2:S3≈11:10:2 can be set, a ratio that clearly reflects the design concept of "smooth air intake, primarily internal circulation, and controllable dehumidification." Specifically, a larger S1 ensures that sufficient hot airflow can smoothly pass through the first through-hole 810 into the receiving cavity 300, providing ample heat to the material tray; a moderate S2 ensures that the second through-hole 820 can support efficient internal circulation, maintaining effective heat utilization; while a smaller S3 ensures that the third through-hole 830 is controllable during dehumidification, avoiding heat loss caused by excessively rapid moisture discharge, while ensuring smooth moisture discharge and maintaining a dry environment within the silo.

[0130] The location of each through-hole can be optimized according to the airflow path. For example, the first through-hole 810 is located on the cavity wall between the receiving cavity 300 and the first cavity 410, away from the second cavity 420. In internal circulation mode, after heating, the gas passes through the first cavity 410 and the first through-hole 810 before entering the receiving cavity 300, and then enters the second cavity 420 through the second through-hole 820. With this flow path, placing the first through-hole 810 (hot air inlet) away from the second cavity 420 (return air outlet) forcibly lengthens the circulation path of the hot air within the receiving cavity. This ensures that the hot air must pass through most of the receiving space before being drawn away, minimizing the risk of airflow "taking shortcuts," thereby significantly improving heat utilization and circulation effectiveness.

[0131] Specifically, the first through-hole 810 is located at the end of the arc-shaped wall 2011 away from the connecting wall 2012, and the second through-hole 820 and the third through-hole 830 are located on the connecting wall 2012. In the internal circulation mode, after heating, the gas passes through the first cavity 410 and the first through-hole 810 into the receiving cavity 300, and then enters the second cavity 420 through the second through-hole 820. In the external circulation mode, after heating, the gas passes through the first cavity 410 and the first through-hole 810 into the receiving cavity 300, and then enters the second cavity 420 through the second through-hole 820, while simultaneously being discharged through the third through-hole 830 and the third cavity 430. In this flow path, the first through-hole 810 (hot air inlet) is located on the arc-shaped wall, while the second through-hole 820 or the third through-hole 830 (return air or exhaust vent) is located on the connecting wall 2012, further clarifying and separating the positions of the inlet and outlet airflows structurally. Hot air is blown directly onto the consumables from the lower curved wall 2011, while the returning air is drawn away from the upper side connecting wall 2012, forming a more reasonable "bottom in, top out" circulation, which improves the efficiency of airflow organization.

[0132] Specifically, among the plurality of second through holes 820, some of the second through holes 820 are provided on the first connecting wall 12a, and some of the second through holes 820 are provided on the second connecting wall 12b. A plurality of third through holes 830 are provided on the second connecting wall 12b.

[0133] Optionally, the shortest distance L1 between the orthographic projections of the plurality of first through holes 810 on the bottom wall of the housing 100 and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing 100, the shortest distance L2 between the orthographic projections of the plurality of second through holes 820 on the bottom wall of the housing 100 and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing 100, and the shortest distance L3 between the orthographic projections of the plurality of third through holes 830 on the bottom wall of the housing 100 and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing 100 satisfy L1 < L2 < L3. The rotation axis of the material tray is parallel to the second direction X.

[0134] In this type of embodiment, by specifically designing the shortest distances L1, L2, and L3 between the orthographic projections of the multiple first through holes 810, second through holes 820, and third through holes 830 on the bottom wall of the housing 100 and the orthographic projection of the material tray rotation axis on the bottom wall of the housing 100, so that they satisfy the relationship L1 < L2 < L3, the airflow organization within the accommodating cavity 300 can be optimized, thereby significantly improving the uniformity and efficiency of heating and drying the 3D printing consumables on the material tray under different working modes.

[0135] In internal circulation mode, the airflow is pumped by the airflow drive mechanism 500, heated by the heating mechanism 600 in the first cavity 410, and then mainly enters the receiving cavity 300 through the first through hole 810 at the shortest distance L1. Since L1 is the smallest, this means that the inlet of the hot airflow is closest to the central axis area of ​​the tray. At the same time, the airflow mainly flows back to the second cavity 420 through the second through hole 820 at a distance L2. Since L1 < L2, the hot airflow enters from a position close to the center of the tray, then diffuses outward and flows out from a relatively outer position, forming a circulating airflow path from the inside out, covering the entire radial direction of the tray. This "center in, circumferential out" airflow organization method can ensure that heat is evenly delivered to all areas of the tray, effectively avoiding the problems of insufficient or excessive heating in the central or edge areas that may occur in traditional designs, thereby significantly improving the uniformity of drying and preheating of consumables on the entire tray.

[0136] When switching to external circulation mode to expel internal moisture, the airflow path includes discharge from the third chamber 430 through the outlet 431. The position of the third through-hole 830 is defined by L3, and L3 is the largest (L1 < L2 < L3). This means that the moisture exhaust outlet (third through-hole 830) is located at the position farthest from the rotating axis of the material tray, i.e., closest to the edge of the receiving cavity 300. During airflow circulation, the gas carrying the moisture of the consumables, after reaching the edge area of ​​the receiving cavity 300, can be captured and discharged most directly and efficiently through these outermost third through-holes 830. This design avoids moisture from lingering in the receiving cavity 300 for a long time or forming circulation dead zones, ensuring that the moisture can be smoothly discharged after following the longest effective path, thereby greatly improving the overall moisture exhaust efficiency and deep drying capacity of the hopper.

[0137] By ensuring L1 < L2 < L3, the forced hot air must enter from the bottom or center of the tray, then disperse upwards and outwards before being drawn away from the outer perimeter of the tray. This "center in, perimeter out" airflow pattern ensures that the airflow must pass through or fully contact the consumable rolls on the tray, greatly improving the penetration and uniformity of drying.

[0138] For example, L1 (hot air inlet) satisfies 0.1R ≤ L1 ≤ 0.3R, such as L1 being 0.1R, 0.2R, or 0.3R. R is the radius of the filament tray, and the mainstream 3D printing filament trays on the market (approximately 200mm in diameter, radius R = 100mm). Within this value range, L1 ensures that the airflow can effectively act on the innermost filament and form an ideal initial airflow field that diffuses from the inside out. Specifically, the shortest distance L1 of the first through-hole 810 satisfies 0.1R ≤ L1 ≤ 0.3R, allowing the hot airflow to directly reach the central area of ​​the filament tray, providing sufficient heat to the inner filament.

[0139] L2 (internal circulation return port) satisfies 0.4R ≤ L2 ≤ 0.7R. For example, L2 can be 0.4R, 0.5R, 0.6R, or 0.7R. If L2 is too close to L1, it will cause an airflow "short circuit," with most of the heat being drawn back before it reaches the outer consumable layer. If it is too close to L3, the distinction between it and the external circulation exhaust port will be minimal. This range ensures that the return port is located precisely within the consumable body area, enabling the most effective driving of uniform heat exchange throughout the entire accommodating cavity 300. Specifically, the shortest distance L2 of the second through-hole 820 satisfies 0.4R ≤ L2 ≤ 0.7R, ensuring that the airflow can properly return after passing through the inner consumable layer, maintaining a stable internal circulation.

[0140] L3 (external circulation exhaust port) satisfies 0.8R ≤ L3 ≤ 1.0R. For example, L3 can be 0.8R, 0.9R, or 1.0R. Setting L3 at the outermost edge ensures that the airflow has the longest "journey" within the receiving cavity 300 before being exhausted, maximizing its interaction time with the consumables and thus removing the most moisture. This range ensures that the exhaust port is located at or very close to the outer edge of the tray, achieving the most efficient moisture removal and preventing moisture that has detached from the consumables from recirculating within the cavity. Specifically, the shortest distance L3 of the third through-hole 830 satisfies 0.8R ≤ L3 ≤ 1.0R, allowing the exhaust port to effectively expel moisture from the hopper.

[0141] Optionally, such as Figure 4 , Figure 7 As shown, the distance H2 between the second through hole 820 and the bottom wall of the housing 100, and the distance between the third through hole 830 and the bottom wall of the housing 100 are both greater than the distance H1 between the first through hole 810 and the bottom wall of the housing 100. The distance H2 between the second through hole 820 and the bottom wall of the housing 100, and the distance between the third through hole 830 and the bottom wall of the housing 100 are both less than or equal to half the height of the housing 100.

[0142] In this type of embodiment, by setting the height of the second through-hole 820 or the third through-hole 830 (return air or exhaust vent) significantly higher than the first through-hole 810 (hot air inlet), the physical law of hot air having low density and naturally rising is cleverly utilized. Hot air enters from a lower position, heats the consumables, and absorbs moisture. The "waste heat air" carrying moisture naturally gathers at the top of the accommodating cavity 300. At this point, setting the return air or exhaust vent at a higher position can greatly improve the efficiency of removing hot and humid air. This allows the entire circulation process to combine the advantages of forced convection and natural convection, further improving drying efficiency and energy saving.

[0143] like Figure 1 and Figure 2 As shown, the airflow switching mechanism 700 includes a first airflow switching mechanism located at the connection between the third cavity 430 and the accommodating cavity 300 for controlling the connection or blockage between the third cavity 430 and the accommodating cavity 300; and a second airflow switching mechanism located at the air inlet 421 for controlling the connection or blockage between the airflow cavity 400 and the outside.

[0144] When it is necessary to introduce external air, the second airflow switching mechanism controls the air passage between the airflow chamber 400 and the outside, allowing external air to smoothly enter the second chamber 420; when it is necessary to prevent external air from entering, the second airflow switching mechanism will block this air passage.

[0145] When it is necessary to discharge the gas in the accommodating cavity 300, the first airflow switching mechanism will control the connection of the air passage between the third cavity 430 and the accommodating cavity 300, so that the gas can flow from the accommodating cavity 300 to the third cavity 430 and finally be discharged; when there is no need to discharge, the first airflow switching mechanism will close this air passage.

[0146] The airflow switching mechanism 700 can be a solenoid valve, using electromagnetic force to control the opening and closing of the valve, thereby controlling the flow of air. It can also be a pneumatic valve, using air pressure difference to drive the valve's movement and control airflow. The airflow switching mechanism 700 can also be an electrically controlled butterfly valve, using a motor to drive the rotation of the butterfly plate to control the flow of air; or it can be a manually operated ball valve, using a rotating handle to change the on / off state of the ball, thus controlling the airflow. The airflow switching mechanism 700 can also be a single-way or multi-way directional valve, allowing multiple single-way directional valves to control the flow of different air paths separately, or a single multi-way directional valve to control the flow of multiple air paths.

[0147] For example, there are two second cavities 420, and correspondingly, there are also two air inlets 421. Therefore, the second airflow switching mechanism designed in this disclosure may include two reversing valves, namely a first reversing valve 710 and a second reversing valve 720, respectively, located at different air inlets 421. Further, there is one third cavity 430, and a first airflow switching mechanism, namely a third reversing valve 730, is configured at the connection between the accommodating cavity 300 and the third cavity 430.

[0148] The drying and dehumidification circulation principle of the silo disclosed herein is as follows:

[0149] like Figure 8 As shown, in the internal circulation mode, the second airflow switching mechanism closes the air inlet 421, blocking the airflow path between the airflow chamber 400 and the outside, and the first airflow switching mechanism blocks the airflow path between the receiving chamber 300 and the third chamber 430. The airflow driving mechanism 500 and the heating mechanism 600 are activated, and the gas begins to flow. The heated airflow undergoes heat buffering in the first chamber 410, and then enters the receiving chamber 300 through the first through hole 810 between the first chamber 410 and the receiving chamber 300 to heat and dry the material tray. Subsequently, the airflow enters the second chamber 420 through the second through hole 820 between the receiving chamber 300 and the second chamber 420, and then the gas in the second chamber 420 returns to the first chamber 410. This cycle forms an internal circulation loop until the temperature in the receiving chamber 300 reaches the set threshold.

[0150] like Figure 9 As shown, the system then enters external circulation mode. The second airflow switching mechanism opens the air inlet 421, connecting the airflow chamber 400 with the outside environment, and the first airflow switching mechanism connects the airflow chamber 300 with the third chamber 430. Outside cold air enters the second chamber 420 through the air inlet 421. After being heated by the heating mechanism 600 and driven by the airflow driving mechanism 500, the heated airflow undergoes heat buffering in the first chamber 410. It then enters the chamber 300 through the first through-hole 810 between the first chamber 410 and the chamber 300, heating and drying the material tray. Afterward, the gas in the chamber 300 carries away the moisture from the material tray, enters the third chamber 430 through the third through-hole 830, and finally exits the hopper through the air outlet 431, forming an external circulation loop and completing the dehumidification process. Meanwhile, the gas in the accommodating cavity 300 can also enter the second cavity 420 through the second through hole 820, and then enter the first cavity 410 from the second cavity 420 to continue circulating, forming an internal circulation loop, until the internal temperature and dryness of the accommodating cavity 300 meet the standards, the air inlet 421 is closed, blocking the air passage between the airflow cavity 400 and the outside, as well as blocking the air passage between the accommodating cavity 300 and the third cavity 430, and the heating mechanism 600 is turned off, and the circulation ends.

[0151] Optionally, such as Figure 1 As shown, the hopper is divided into a drying and dehumidification zone 110 and a non-drying zone 120. Specifically, the housing 100 can be divided into the drying and dehumidification zone 110 and the non-drying zone 120, with the base 200 located in the drying and dehumidification zone 110. In actual use, different consumables have different temperature and humidity requirements. Some consumables do not require drying and dehumidification and can be placed in the non-drying zone 120, while others require drying and dehumidification and can be placed in the drying and dehumidification zone 110. This arrangement can meet the usage requirements of different consumables, allowing the hopper to accommodate multiple consumables simultaneously and improving its compatibility.

[0152] This disclosure also provides a 3D printing feeding device, including a material tray and a hopper. The hopper includes a housing 100 and a base 200. The housing 100 has an air inlet 421 and an air outlet 431 communicating with the outside. The base 200 is disposed inside the housing 100, and the base 200 divides the inner cavity of the housing 100 into at least a receiving cavity 300 for receiving the material tray and an airflow cavity 400. The airflow cavity 400 includes a first cavity 410, a second cavity 420, and a third cavity 430. The first cavity 410 communicates with the receiving cavity 300 and is provided with a heating mechanism 600. The second cavity 420 communicates with the receiving cavity 300, the air inlet 421, and the first cavity 410, and is provided with an airflow driving mechanism 500, which is disposed close to the heating mechanism 600. The third cavity 430 communicates with the receiving cavity 300 and the air outlet 431.

[0153] The airflow drive mechanism 500, the first cavity 410, the second cavity 420 and the accommodating cavity 300 constitute an internal circulation loop. The airflow drive mechanism 500 is used to pump gas from the second cavity 420 through the first cavity 410 to the accommodating cavity 300 and then back to the second cavity 420.

[0154] The airflow drive mechanism 500, the air inlet 421, the second cavity 420, the first cavity 410, the accommodating cavity 300, the third cavity 430 and the air outlet 431 constitute an external circulation loop. The airflow drive mechanism 500 is at least used to pump gas from the air inlet 421 through the second cavity 420, the first cavity 410 and the accommodating cavity 300 to the third cavity 430 and then discharge it from the air outlet 431.

[0155] The hopper operates in two modes: internal circulation and external circulation. In internal circulation mode, the airflow path is an internal circulation loop, while in external circulation mode, the airflow path includes both an internal circulation loop and an external circulation loop. The hopper also includes an airflow switching mechanism 700 for switching between internal and external circulation modes.

[0156] The receiving cavity 300 may be located above the airflow cavity 400 and is used to receive a tray. The shape of the receiving cavity 300 may be set according to the shape of the tray. Multiple trays may be placed within the receiving cavity 300. Optionally, the receiving cavity 300 may include at least one tray unit, each tray unit including multiple tray areas, and one tray area can hold one tray. Exemplarily, the receiving cavity 300 includes one tray unit, and each tray unit includes at least two tray areas. The tray areas within a single tray unit are interconnected.

[0157] The material trays are located in the receiving cavity 300. Specifically, there are multiple material trays, each placed in a corresponding material tray area. The feeding device also includes a material feeding mechanism, with one material feeding mechanism corresponding to each material tray, used to complete the loading or unloading of materials.

[0158] The detailed structure of each component of the silo can be found in the above embodiments, and will not be described in detail here.

[0159] This disclosure also provides a 3D printing apparatus, including a 3D printer and a 3D printing feed device as described in any of the above embodiments, the 3D printing feed device being used to supply consumables to the 3D printer.

[0160] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A hopper for a 3D printing feeding device, characterized in that, Includes: a housing, wherein the housing is provided with an air inlet and an air outlet that communicate with the outside; A base, disposed within the housing, divides the interior cavity of the housing into at least: A receiving cavity for accommodating a tray; and airflow cavity; The airflow cavity includes: The first cavity is connected to the receiving cavity and is equipped with a heating mechanism; A second cavity, communicating with the accommodating cavity, the air inlet, and the first cavity, and equipped with an airflow driving mechanism, the airflow driving mechanism being disposed near the heating mechanism; and The third cavity is connected to the accommodating cavity and the air outlet; The airflow driving mechanism, the first cavity, the second cavity, and the accommodating cavity constitute an internal circulation loop. The airflow driving mechanism is used to pump gas from the second cavity through the first cavity to the accommodating cavity and then back to the second cavity. The airflow driving mechanism, the air inlet, the second cavity, the first cavity, the accommodating cavity, the third cavity, and the air outlet constitute an external circulation loop. The airflow driving mechanism is at least used to pump gas from the air inlet through the second cavity, the first cavity, and the accommodating cavity to the third cavity and discharge it from the air outlet. The silo operates in two modes: an internal circulation mode and an external circulation mode. The airflow path in the internal circulation mode is an internal circulation loop, and the airflow path in the external circulation mode includes both an internal circulation loop and an external circulation loop. The hopper also includes an airflow switching mechanism for switching between the internal circulation mode and the external circulation mode.

2. The silo according to claim 1, characterized in that, The first cavity is located on one side of the second cavity along the first direction, and the third cavity is located on one side of the second cavity along the second direction, wherein the first direction and the second direction intersect.

3. The silo according to claim 2, characterized in that, The airflow cavity includes two first cavities, two second cavities, and one third cavity; Each of the first cavities is equipped with the heating mechanism, and each of the second cavities is equipped with the airflow driving mechanism.

4. The silo according to claim 3, characterized in that, The two second cavities are arranged at intervals along the second direction, and the third cavity is located between the two second cavities.

5. The silo according to claim 2, characterized in that, The second direction is perpendicular to the rotation plane of the tray, and the first direction is perpendicular to the second direction and parallel to the rotation plane of the tray.

6. The silo according to claim 4, characterized in that, The two second cavities are arranged symmetrically about a first plane, which is parallel to the rotation plane of the tray and passes through the central axis of the receiving cavity.

7. The silo according to any one of claims 1-6, characterized in that, The projected area of ​​the first cavity on the bottom wall of the housing is greater than the projected area of ​​the second cavity on the bottom wall of the housing.

8. The silo according to any one of claims 1-6, characterized in that, The airflow switching mechanism includes a first airflow switching mechanism disposed at the communication point between the third cavity and the receiving cavity, used to control the connection or blockage between the third cavity and the receiving cavity; and A second airflow switching mechanism is provided at the air inlet to control whether the airflow cavity is connected to or blocked from the outside.

9. The silo according to any one of claims 1-6, characterized in that, The cavity wall between the accommodating cavity and the first cavity is provided with a plurality of first through holes, and the accommodating cavity communicates with the first cavity through the first through holes; The cavity wall between the receiving cavity and the second cavity is provided with a plurality of second through holes, and the receiving cavity communicates with the second cavity through the second through holes; The cavity wall between the accommodating cavity and the third cavity is provided with a plurality of third through holes, and the accommodating cavity communicates with the third cavity through the third through holes.

10. The silo according to claim 9, characterized in that, The total maximum ventilation volume S1 of the plurality of first through holes, the total maximum ventilation volume S2 of the plurality of second through holes, and the total maximum ventilation volume S3 of the plurality of third through holes satisfy S1 ≥ S2 > S3.

11. The silo according to claim 9, characterized in that, The first through hole is located on the cavity wall between the accommodating cavity and the first cavity body, away from the second cavity body.

12. The silo according to claim 9, characterized in that, The shortest distance L1 between the orthographic projection of the plurality of first through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, the shortest distance L2 between the orthographic projection of the plurality of second through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, and the shortest distance L3 between the orthographic projection of the plurality of third through holes on the bottom wall of the housing and the orthographic projection of the rotation axis of the material tray on the bottom wall of the housing, satisfy L1 < L2 < L3.

13. The silo according to claim 11, characterized in that, The distance between the second through hole and the bottom wall of the housing, and the distance between the third through hole and the bottom wall of the housing, are both greater than the distance between the first through hole and the bottom wall of the housing; The distance between the second through hole and the bottom wall of the housing, and the distance between the third through hole and the bottom wall of the housing, are both less than or equal to half the height of the housing.

14. A 3D printing feeding device, characterized in that, It includes a material tray and a hopper as described in any one of claims 1 to 13, wherein the material tray is located in the receiving cavity.

15. A 3D printing device, characterized in that, Includes a 3D printer and a 3D printing feed device as described in claim 14, the 3D printing feed device being used to supply consumables to the 3D printer.

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