3D printing apparatus and method

Abstract

The application provides a 3D printing device and method. The device comprises: a material extrusion part, including a material cavity and an extrusion opening in communication with the material cavity, the material cavity being used for accommodating a molten material, and the extrusion opening being used for extruding the molten material to a current printing layer; and a switch assembly coupled with the extrusion opening, the switch assembly being used for controlling the on-off of the area where the extrusion opening is located, so as to form a plurality of sub-extrusion openings with continuously adjustable width. Through such a configuration, the molten material can fill and print the current printing layer including a plurality of sub-areas through the plurality of sub-extrusion openings at one time, so as to further improve the printing efficiency while ensuring the printing precision.

Description

Technical Field

[0001] This application relates to the field of 3D printing, specifically to a 3D printing apparatus and method. Background Technology

[0002] Material extrusion-based 3D printing technologies, such as fused deposition modeling (FDM), are commonly used 3D printing technologies. They typically require heating the material to a molten (or semi-fluid) state and then extruding the molten material from the extrusion port of the 3D printing device onto the forming stage, so that the material is deposited layer by layer on the forming stage and solidified together to form a 3D printed part.

[0003] In traditional material extrusion-based 3D printing technology, 3D printing devices typically have extrusion nozzles with a fixed diameter. These devices cannot simultaneously achieve both printing accuracy and efficiency. Although related technologies have made some improvements to these devices, enabling them to balance printing efficiency and accuracy, there is still room for further improvement in the printing efficiency of these improved 3D printing devices. Summary of the Invention

[0004] This application provides a 3D printing apparatus and method to further improve printing efficiency while ensuring printing accuracy.

[0005] In a first aspect, a 3D printing apparatus is provided, comprising: a material extrusion section including a material cavity and an extrusion port communicating with the material cavity, the material cavity being used to contain molten material, and the extrusion port being used to extrude the molten material into a current printing layer; and a switching assembly coupled to the extrusion port, the switching assembly being used to control the on / off state of the area where the extrusion port is located to form a plurality of sub-extrusion ports with continuously adjustable widths, the plurality of sub-extrusion ports being used to simultaneously print a plurality of partitions in the current printing layer, and during the printing of the plurality of partitions using the plurality of sub-extrusion ports, the width of each of the plurality of sub-extrusion ports changes with the outline of the partition corresponding to each sub-extrusion port, thereby filling the molten material into the partition corresponding to each sub-extrusion port in one go.

[0006] In a second aspect, a 3D printing apparatus is provided, comprising: a material extrusion section including a material cavity and an extrusion port, the material cavity being used to contain molten material, the extrusion port including a plurality of channels communicating with the material cavity, the plurality of channels being used to extrude the molten material to a current printing layer, and the material extruded from adjacent channels in the plurality of channels fusing together in the current printing layer; and a switching assembly coupled to the plurality of channels, the switching assembly being used to control the on / off state of the plurality of channels to form a plurality of sub-extrusion ports with continuously adjustable widths.

[0007] Thirdly, a 3D printing method is provided, comprising: conveying molten material to an extruder to print a current printing layer; during the printing of the current printing layer, using a switching component to control the on / off state of the area where the extruder is located to form a plurality of sub-extruders with continuously adjustable widths, the plurality of sub-extruders being used to simultaneously print a plurality of partitions in the current printing layer, and during the printing of the plurality of partitions using the plurality of sub-extruders, the width of each of the plurality of sub-extruders changes with the change of the outline of the partition corresponding to each sub-extruder, thereby filling the partition corresponding to each sub-extruder with the molten material in one go.

[0008] Fourthly, a 3D printing method is provided, comprising: conveying molten material to an extrusion port to print a current printing layer using multiple channels in the extrusion port, wherein the material extruded from adjacent channels in the multiple channels is fused together in the current printing layer; during the printing of the current printing layer, using a switching component to control the on / off state of the multiple channels to form multiple sub-extrusion ports with continuously adjustable widths.

[0009] The 3D printing apparatus provided in this application embodiment includes a switching component coupled to the extrusion orifice. This switching component can control the on / off state of the area where the extrusion orifice is located to form multiple sub-extrusion orifices with continuously adjustable widths. This configuration allows molten material to fill and print the current printing layer, which includes multiple partitions, through multiple sub-extrusion orifices in a single operation, thereby improving printing efficiency while ensuring printing accuracy. Attached Figure Description

[0010] Figure 1 This is a schematic diagram of the printing layer structure in an embodiment of this application.

[0011] Figure 2 This is a schematic diagram of the structure of a 3D printing device provided in an embodiment of this application.

[0012] Figure 3 for Figure 2A schematic diagram of the 3D printing device in another printing state.

[0013] Figure 4 This is a schematic diagram of another 3D printing apparatus provided in an embodiment of this application.

[0014] Figure 5 for Figure 4 A schematic diagram of the 3D printing device in another printing state.

[0015] Figure 6 The 3D printing apparatus provided in the embodiments of this application is used for... Figure 1 A schematic diagram of the structure during printing of the printing layer.

[0016] Figure 7 This is a top view of the 3D printing apparatus provided in an embodiment of this application.

[0017] Figure 8 This is a top view of another 3D printing apparatus provided in an embodiment of this application.

[0018] Figure 9 This is a schematic diagram of the structure of a switch assembly in a 3D printing device provided in an embodiment of this application.

[0019] Figure 10 This is a schematic diagram of the structure of a switch assembly in another 3D printing device provided in an embodiment of this application.

[0020] Figure 11 This is a schematic diagram of the structure of a switch assembly in another 3D printing device provided in an embodiment of this application.

[0021] Figure 12 This is a schematic diagram of another 3D printing device provided in an embodiment of this application.

[0022] Figure 13 This is a schematic diagram of the structure of a switch assembly in another 3D printing device provided in an embodiment of this application.

[0023] Figure 14 This is a flowchart illustrating a 3D printing method provided in an embodiment of this application.

[0024] Figure 15 This is a flowchart illustrating another 3D printing method provided in an embodiment of this application. Detailed Implementation

[0025] The technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. It should be understood that the same or similar reference numerals are used in the drawings to represent the same or similar components.

[0026] In material extrusion-based 3D printing technologies (such as FDM), 3D printing equipment can adapt to a wide variety of printing materials, and the size range of the printed parts can also be very wide, thus it is widely used in the 3D printing field. This type of 3D printing equipment requires extruding molten material through its extrusion port (or discharge port) onto a forming stage, where the molten material is deposited layer by layer and solidified to form the 3D printed part. Therefore, this type of 3D printing equipment typically requires layer-by-layer printing of the 3D printed part.

[0027] Generally, printing each layer using a 3D printer is equivalent to filling the infill area of ​​each layer. Since traditional 3D printers typically have extrusion nozzles with a fixed diameter, when printing one layer out of multiple layers, the infill area of ​​that layer usually needs to be divided into several closely spaced passes (each pass's size matches the nozzle's diameter), and the printer must be controlled to fill these passes sequentially in a certain order. In other words, printing one layer typically requires multiple passes to completely fill the infill area of ​​that layer.

[0028] If the extrusion nozzle of a 3D printer has a small diameter, it extrudes less material per unit time. When printing a single layer, more filling passes are needed, resulting in relatively high printing accuracy but relatively low printing efficiency. Conversely, if the extrusion nozzle has a large diameter, it extrudes more material per unit time, requiring fewer filling passes when printing the same layer. This results in relatively high printing efficiency but relatively low printing accuracy. Therefore, traditional 3D printers cannot simultaneously achieve both printing accuracy and printing efficiency.

[0029] To meet the industrial demand for high-efficiency and high-precision printing, a feasible approach is to modify the extrusion nozzle of the 3D printing device to be a variable-width nozzle. This type of 3D printing device's nozzle has a one-dimensional strip characteristic; that is, the width of the nozzle in one dimension is much greater than its width in another dimension, and the nozzle's width in this one-dimensional direction can change with the contour of the infill area of ​​the current printed layer, thus forming a variable-width nozzle. Specific descriptions of this implementation can be found, for example, in PCT / CN2017 / 083647 and PCT / CN2020 / 120405.

[0030] Because the width of the extrusion nozzle in this improved 3D printing device is variable, when the printed layer is a single connected region, this type of 3D printing device can completely or partially fill the entire printed layer in one go, thus balancing printing accuracy and printing efficiency.

[0031] However, for some complex 3D printed parts (e.g., 3D printed parts with hollow structures), the printing efficiency using the improved 3D printing equipment described above is still relatively low. The following section combines... Figure 1 This will be briefly illustrated by example.

[0032] As mentioned earlier, 3D printed parts can have multiple printing layers. Figure 1 The image shown is one of multiple printing layers. For example... Figure 1 As shown, the printed layer 1 has multiple hollow areas a. When using an improved 3D printing device... Figure 1 When printing the shown printing layers, the 3D printing device needs to follow the direction shown. Figure 1 The printing direction (y) needs to be reciprocated 6 times to ensure that the molten material extruded from the extruder completely fills the filling area of ​​the printed layer.

[0033] Due to the presence of the cutout region 'a', this printed layer becomes a complex-shaped printed layer. Of course, complex-shaped printed layers include more than just... Figure 1 The printed layer shown can also be in other forms. As long as the filled area of ​​the printed layer is discontinuous or has isolation spaces in the filled area, the printed layer can be considered a printed layer with a complex shape.

[0034] For example, the complex-shaped printed layer can be a filling region with multiple connected areas. Alternatively, the filling region of the complex-shaped printed layer can be a region with a multi-channel separation structure, that is, under one movement trajectory of the printing device (e.g., the movement trajectory can be a straight line), the filling region can have multiple partitions (partitions can also be called filling channels), and these multiple partitions can be separated (or isolated) from each other.

[0035] In some embodiments, the number of partitions in the filled area can vary within a single movement trajectory of the printing device. For example, in a portion of the printing trajectory, the partitions may be separate from each other, while in another portion, some or all of the partitions may form a single partition. It should be understood that whether it is a single partition formed by multiple partitions or each partition within multiple partitions, a single partition can refer to a simply connected region, and the width of the outline of a single partition can be along the printing direction (e.g., ...). Figure 1 The printing direction (y) shown is dynamically changing.

[0036] The structurally complex 3D printed parts described in this application embodiment can refer to 3D printed parts that include the aforementioned complex-shaped printed layers. Furthermore, a structurally complex 3D printed part may include one or more complex-shaped printed layers.

[0037] As mentioned earlier, for Figure 1 The illustrated printing layer requires six reciprocating motions in the improved 3D printing apparatus to completely fill the filled area of ​​the printing layer. If the 3D printed part includes multiple complex-shaped printing layers, the printing efficiency of the improved 3D printing apparatus is still low and needs further improvement.

[0038] In view of this, embodiments of this application provide a 3D printing apparatus. The following describes the apparatus in conjunction with... Figure 2 The 3D printing apparatus 2 in the embodiments of this application will be described in detail. It should be understood that the 3D printing apparatus mentioned in the embodiments of this application refers to an apparatus used for 3D printing. The 3D printing apparatus can refer to the entire 3D printing system or a part of the 3D printing system. For example, the 3D printing apparatus can refer to a 3D print head.

[0039] See Figure 2 The 3D printing device 2 may include a material extrusion section 3 and a switching assembly 4.

[0040] The material extrusion section 3 includes a material cavity 31 and an extrusion port 32. A material inlet 33 may be provided in the material cavity 31. The material cavity 31 can receive molten material through the material inlet 33 and is used to contain the molten material. The extrusion port 32 communicates with the material cavity 31 and is used to extrude the molten material in the material cavity 31 to the current printing layer.

[0041] The current printing layer can be located on the forming stage ( Figure 2 (Not shown in the image). In the embodiments of this application, the current printing layer refers to a printing layer that is being printed during the printing of a 3D printed part, such as the complex-shaped printing layer described above.

[0042] See also Figure 2 The switch assembly 4 is coupled to the extrusion port 32 to control the on / off state of the area where the extrusion port 32 is located, so that it forms multiple sub-extrusion ports 34 with continuously adjustable widths.

[0043] It should be understood that the coupling of the switching assembly 4 with the extrusion port 32 is for the purpose of controlling the on / off state of the area where the extrusion port 32 is located. This on / off control can be understood as blocking or not blocking the extrusion of molten material from a portion of the area where the extrusion port 32 is located, thereby forming multiple sub-extrusion ports 34 with continuously adjustable widths in the area where the extrusion port 32 is located. The specific location of the blocked portion can be dynamically adjusted by controlling the switching assembly 4.

[0044] In other words, when the switching component 4 does not control the on / off state of the area where the extrusion port 32 is located, that is, when the switching component 4 does not block the molten material from being extruded from the extrusion port 32, the extrusion port 32 can be in the form of a single extrusion port. This extrusion port 32 can be the continuously adjustable width extrusion port described above, and the printing of the current printing layer, which is formed as a single partition, can be completed in one go using this extrusion port 32.

[0045] In some embodiments, the switch assembly 4 can also be understood as a shielding member capable of shielding the area where the extrusion port 32 is located.

[0046] When the switching assembly 4 controls the on / off state of the area where the extrusion port 32 is located, that is, when the switching assembly 4 blocks the molten material from being extruded from a portion of the area where the extrusion port 32 is located, the extrusion port 32 becomes multiple sub-extrusion ports 34, and the width of each sub-extrusion port is continuously adjustable. In view of this, the printing of the current printing layer, which includes multiple partitions, can be completed in one go using multiple sub-extrusion ports.

[0047] It should be noted that, in the embodiments of this application, the one-time completion of printing the current printing layer can mean that when the 3D printing device is filling and printing along the printing direction, it only needs to move once in a single direction to complete the filling of the current printing layer's filling area. For example, controlling the printing device to move once in a straight line can complete the filling and printing of the complex-shaped current printing layer described above in one go.

[0048] This application embodiment provides a switching component coupled to the extrusion port for the 3D printing device, and controls the opening and closing of the extrusion port through the switching component to form multiple sub-extrusion ports with continuously adjustable widths. This allows molten material to fill and print the current printing layer containing multiple partitions at one time through multiple sub-extrusion ports, thereby ensuring printing accuracy while further improving printing efficiency.

[0049] As mentioned above, if the current printed layer is a complex-shaped printed layer, it should include multiple partitions, and the width of the outline of each partition can vary along the printing direction. When printing this current printed layer, the multiple sub-extrusion ports 34 described above can be used to print multiple partitions of the current printed layer simultaneously. During the printing process, the width of each sub-extrusion port 34 can vary with the outline of the partition corresponding to each sub-extrusion port, thereby filling the partition corresponding to each sub-extrusion port with molten material in one go.

[0050] Therefore, when the current printing layer is a complex-shaped printing layer as described above, the 3D printing device of this application embodiment can complete the printing of the current printing layer in one go, and the efficiency improvement effect is particularly obvious.

[0051] In this embodiment of the application, there are no specific limitations on the structure of the extrusion port 32 and the coupling form between the switch assembly 4 and the extrusion port 32, as long as the relevant settings of the switch assembly 4 and the extrusion port 32 can enable the switch assembly 4 to control the on / off state of the area where the extrusion port 32 is located.

[0052] As one implementation method, such as Figure 2 and Figure 3 As shown, the extrusion port 32 can be an extrusion port formed through the gap between two pistons 321. These two pistons 321 can extend along... Figure 2 and Figure 3 The two movable blocks 321 slide relative to each other in the x direction, thereby changing the gap between them to form an extrusion port 32 with variable width.

[0053] Accordingly, the switching component 4 can be coupled to the extrusion port 32 to control a portion of the extrusion port 32 to be blocked while another portion is not blocked, thereby forming a plurality of continuously adjustable sub-extrusion ports 34. The blocked or unblocked portions can be dynamically changed according to the control of the switching component 4.

[0054] For example, such as Figure 2 and Figure 3 As shown, the switch assembly 4 can be configured to include multiple slider switches with variable widths and movable positions (such as...). Figure 2 and Figure 3 (As shown in 41, 42, and 43). The coupling method between the switch assembly 4 and the extrusion port 32 can be such that each slider switch can be controlled by the switch assembly 4 to move to the corresponding position in the area where the extrusion port 32 is located at any time and in any motion manner. For example, each slider switch can be disposed within the material cavity 31 and can move along the material cavity 31 under the control of the switch assembly 4. Figure 2and Figure 3 The relative sliding in the x-direction and / or along Figure 2 and Figure 3 Move in the y-direction.

[0055] exist Figure 2 In this configuration, the switch assembly 4 can control the slider switches 42 and 43 to move to the area where the extrusion port 32 is located, while controlling the slider switch 41 to move away from the area where the extrusion port 32 is located, thereby isolating the extrusion port 32 as... Figure 2 The three sub-extrusion ports 34 are shown. Because slider switches 42 and 43 can also move along... Figure 2 The x-direction of the nozzles can be slid relative to each other, thus allowing the widths of the three sub-extrusion nozzles 34 to be arbitrarily changed. Accordingly, the filling area in the current printed layer in the printing state can include three mutually separate partitions.

[0056] Similarly, in Figure 3 In this configuration, the switch assembly 4 can control the slider switches 41, 42, and 43 to move to the area where the extrusion port 32 is located, thereby isolating the extrusion port 32 as... Figure 3 The four sub-extrusion ports 34 are shown. The filling area in the current printed layer during this printing state can include four mutually separate partitions. Figure 3 and Figure 2 It can be the printing state of the printing device 2 at different printing positions along the printing direction when printing the current printing layer.

[0057] Through the above coupling method, the area where the extrusion port is located can be formed into multiple sub-extrusion ports 34 with continuously adjustable widths. The number and width of the sub-extrusion ports can be flexibly changed by the control of the switch component 4. This allows the molten material to fill and print the complex-shaped current printing layer at one time through these multiple sub-extrusion ports, thereby ensuring printing accuracy while further improving printing efficiency.

[0058] As another implementation method, such as Figure 4 and Figure 5As shown, the extrusion port 32 may include a plurality of channels 35. These channels 35 communicate with the material cavity 31 and are used to extrude molten material into the current printed layer. The plurality of channels 35 can be closely arranged so that the material extruded from adjacent channels fuses together in the current printed layer. That is, the extrusion port 32 is divided into a plurality of channels 35, for example, into an array of channels having at least one row of channels 35, with the channels separated by channel walls (or partitions). The arrangement of the plurality of channels 35 allows the molten material extruded from each channel to flow under its own weight and form a connected printed layer (or coating) when coated on the forming stage. Of course, in some embodiments, auxiliary means (such as mechanical rolling) can also be used to ensure the fusion effect of the material extruded from the plurality of channels 35.

[0059] This application does not impose specific limitations on the arrangement of the multiple channels 35, as long as the material extruded from adjacent channels 35 can fuse together in the current printing layer. In some embodiments, such as Figure 7 As shown, the plurality of channels 35 can be arranged in a row and closely adjacent to each other. In other embodiments, such as Figure 8 As shown, multiple closely spaced channels 35 can be arranged in an alternating manner and closely close to each other in order to make effective use of the accommodating space.

[0060] Accordingly, the switching assembly 4 can be coupled to multiple channels 35 to control the on / off state of the multiple channels 35, thereby forming multiple sub-extrusion ports 34 with continuously adjustable widths. In other words, the switching assembly 4 can control some of the multiple channels 35 to extrude molten material, and the switching assembly can also control some of the multiple channels 35 to prevent the extrusion of molten material. Channels that can extrude molten material and are adjacent to each other can form a sub-extrusion port 34. Adjacent sub-extrusion ports 34 can be isolated from each other by channels 35 that cannot extrude molten material. Whether each of the multiple channels 35 forming the extrusion port 32 can extrude molten material can be dynamically changed according to the control of the switching assembly 4.

[0061] For example, such as Figure 4 and Figure 5 As shown, the coupling method can be to configure the switch assembly 4 as multiple switches corresponding one-to-one with multiple channels 35 (e.g., ...). Figure 4 and Figure 5 As shown in A, B, C, D, E, and F, each switch can individually control the corresponding channel.

[0062] exist Figure 4 In this configuration, switch assembly 4 can control switches A, D, and F to open (i.e., move away from channel 35), while controlling the other switches to close (i.e., abut against channel 35), thereby enabling multiple channels 35 to form a configuration such as... Figure 4 The three sub-extrusion ports 34 are shown. Accordingly, the filling area in the current printed layer in the current printing state can include three mutually separate partitions.

[0063] exist Figure 5 In the middle, the switch assembly 4 can control switches C, D, and F to open, while controlling the other switches to close, thereby allowing multiple channels 35 to be formed as follows: Figure 5 The two sub-extrusion ports 34 are shown. The filled area in the current printed layer during this printing state can include two separate partitions. Figure 4 and Figure 5 It can be the printing state of the printing device 2 at different printing positions along the printing direction when printing the current printing layer.

[0064] In the above coupling method, the multiple channels 35 formed as extrusion ports 32 can be controlled to extrude molten material from some of the channels 35, thereby forming multiple sub-extrusion ports 34 with continuously adjustable widths. The number and width of the sub-extrusion ports can be varied by controlling the switch assembly 4, so that the molten material can be filled and printed into the complex-shaped current printing layer at one time through the multiple sub-extrusion ports, thereby ensuring printing accuracy and further improving printing efficiency.

[0065] In addition, compared with the solution described above, this solution can avoid the phenomenon of uneven material flow caused by the narrowing of the extrusion position width when the width of the extrusion port 32 and each sub-extrusion port 34 is changed, which compresses the molten material and can effectively improve the printing quality of 3D printed parts.

[0066] As mentioned earlier, the number of partitions within the infill area corresponding to a complex-shaped current print layer can vary. For example, as... Figure 1 As shown, the current printed layer 1 includes multiple partitions, including a first partition 11 and a second partition 12. In the partially filled area (dashed area 10), the first partition 11 and the second partition 12 have mutually isolated regions; in the partially filled area (area 10' below the dashed area 10), the first partition 11 and the second partition 12 have mutually connected regions. The dashed area 10 and area 10' can be closely arranged along the printing direction y. Specifically, in area 10, the first partition 11 and the second partition 12 are mutually isolated, that is, the first partition 11 and the second partition 12 form a total of 2 partitions; in area 10', the first partition 11 and the second partition 12 are merged into one partition 13.

[0067] Corresponding to this, such as Figure 6As shown, the 3D printing apparatus 2 in this embodiment may include a first sub-extrusion port 341 and a second sub-extrusion port 342. When printing region 10 using the 3D printing apparatus 2, the on / off control of the switch assembly 4 causes the first sub-extrusion port 341 and the second sub-extrusion port 342 to be used to print the mutually isolated first partition 11 and second partition 12, respectively. When printing region 10', the on / off control of the switch assembly 4 causes the first sub-extrusion port 341 and the second sub-extrusion port 342 to merge into a single sub-extrusion port 343, and the merged sub-extrusion port 343 can be used to print partition 13, which is the merged partition 11 and the second partition 12.

[0068] By controlling the on / off states of different filling areas of the current printing layer using the switching component 4, the 3D printing device can further achieve the ability to print more complex current printing layers in a single operation (e.g., for...). Figure 1 The current printing layer shown only requires the printing device 2 to move along the printing direction y once to complete the printing, thus effectively improving the printing efficiency of 3D printed parts containing such printing layers.

[0069] As mentioned above, the structure of the switch assembly 4 can be varied, and this application embodiment does not specifically limit it.

[0070] As one implementation method, such as Figures 7-12 As shown, the switching assembly 4 may include a plurality of sheet switches 44. These sheet switches 44 can deform under temperature and / or voltage control, thereby controlling the on / off state of the area where the extrusion port 32 is located (e.g., the channel 35). For example, as... Figure 7-8 As shown, a corresponding sheet switch 44 can be provided for each channel 35 to individually control whether molten material can be extruded from the corresponding channel 35 by the deformation of each sheet switch. The width of the sheet switch 44 can typically be set to be greater than or equal to the diameter of the channel 35 to achieve better blocking effect when the switching assembly 4 blocks each channel 35. The plurality of sheet switches 44 may include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

[0071] The following is combined with Figures 9-11 This section details the arrangement of the switch assembly 4, which includes multiple sheet switches 44. It should be understood that... Figure 9 and Figure 10 This example uses only one sheet switch; the setup for other sheet switches is the same as shown in the diagram.

[0072] like Figure 9As shown, the sheet switch 44 can be disposed inside the material cavity 31 and above the area where the extrusion port 32 is located (e.g., the channel 35). Specifically, the sheet switch 44 can be fixed at one end in a cantilever manner, while the other end can be deformed under the control of temperature and / or voltage to abut against or move away from the area where the extrusion port 32 is located.

[0073] For example, when the sheet switch 44 is a piezoelectric bicrystalline wafer, the direction of the electric field of the upper and lower piezoelectric wafers can be controlled, so that when the piezoelectric bicrystalline wafer bends downward, the area where the extrusion port 32 is located (e.g., the channel 35) is closed (e.g., when the piezoelectric bicrystalline wafer bends downward). Figure 9 (a) shows); while under a reverse electric field, when the piezoelectric bicrystalline wafer is bent upwards, the region where the extrusion port 32 is located (e.g., channel 35) opens (e.g. Figure 9 (b) shown).

[0074] Similarly, when the sheet switch 44 is a bimetallic strip, the active layer can be positioned below, and by controlling it to bend the passive layer downwards at a lower temperature and upwards at a higher temperature.

[0075] Alternatively, when the sheet switch 44 is a thermally expanding metal resistor or shape memory alloy, it can also be configured in the above manner. The difference is that this type of sheet switch 44 only requires one layer to achieve on / off control of the area where the extrusion port 32 is located.

[0076] Shape memory alloys, also known as memory alloys, are materials that can be flat at one given temperature and bent downwards at another. Therefore, controlling their given temperature allows the shape memory alloy sheet to drive a transmission component up and down. In the embodiments of this application, the temperature of the shape memory alloy can be controlled in different ways. For example, it can be energized to control the temperature using resistance heating, or it can be controlled using radiant heating.

[0077] A thermally expanding metal resistor can also be called a high thermal expansion coefficient metal resistance element. At room temperature, a thermally expanding metal resistor is in a flat state. However, when an electric current is applied to heat the thermally expanded metal resistor, its thermal expansion increases its length, causing the metal resistor to bend downwards. Therefore, controlling its temperature can cause the thermally expanded metal resistor to drive a transmission component to move up and down.

[0078] In other embodiments, such as Figure 10 and Figure 11As shown, the sheet switch 44 can be disposed outside the material cavity 31, and the sheet switch 44 is connected to the transmission component 45 (it should be understood that multiple sheet switches can be connected to multiple transmission components 45 respectively), and the transmission component 45 controls the on / off state of the area where the extrusion port 32 is located (e.g., multiple channels 35).

[0079] The transmission element 45 can be a blocking block, which can be positioned above the area where the extrusion port 32 is located, and can move up and down according to the deformation of the sheet switch 44. One end of the transmission element 45 is fixedly connected to the sheet switch 44, and the other end can abut against or move away from the area where the extrusion port 32 is located (e.g., the channel 35). This application embodiment does not specifically limit the shape and material of the transmission element 45. For example, the transmission element 45 can be a square or cylindrical blocking block, and its material can be metal, ceramic, or other materials that can withstand high temperatures and have sufficient strength.

[0080] This application does not specifically limit the method of fixing the sheet switch 44 outside the material cavity 31. As one implementation method, such as... Figure 10 As shown, the sheet switch 44 can be cantilevered and fixed to the outside of the material cavity 31. Specifically, one end is fixed, and the other end is connected to the transmission member 45. The other end can deform under the control of temperature and / or voltage to drive the transmission member 45 to move up and down to abut against or away from the area where the extrusion port 32 is located.

[0081] For example, when the sheet switch 44 is a piezoelectric bicrystalline wafer or a bimetallic strip, the electric field direction of the upper and lower piezoelectric wafers or the temperature of the bimetallic strip can be controlled, so that when the piezoelectric bicrystalline wafer or bimetallic strip bends downward, the area where the extrusion port 32 is located (e.g., the channel 35) is closed (e.g., when the piezoelectric bicrystalline wafer or bimetallic strip bends downward). Figure 10 (a) shows); and when the piezoelectric bicrystalline wafer or bimetallic sheet is bent upwards or straightened, the area where the extrusion port 32 is located (e.g., channel 35) is opened (e.g., as shown in (a)). Figure 10 (b) shown).

[0082] Alternatively, the sheet switch 44 can also be made of a thermally expanding metal resistor or a shape memory alloy, and the fixing method is the same as above. The difference is that this type of sheet switch 44 can achieve on / off control of the area where the extrusion port 32 is located with only one sheet, thereby simplifying the structure of the sheet switch 44.

[0083] As another implementation method, such as Figure 11As shown, the sheet switch 44 can be fixed to the outside of the material cavity 31 with both ends fixed. For example, both ends of the sheet switch 44 can be fixed to a bracket 36 outside the material cavity. The transmission member 45 can be located at any position between its two ends. The sheet switch 44 can deform under the control of temperature and / or voltage to drive the transmission member 45 to move up and down to abut or move away from the area where the extrusion port 32 is located.

[0084] For example, when the sheet switch 44 is a piezoelectric bicrystalline wafer or a bimetallic strip, the electric field direction of the upper and lower piezoelectric wafers or the temperature of the bimetallic strip can be controlled, so that when the piezoelectric bicrystalline wafer or bimetallic strip bends downward, the area where the extrusion port 32 is located (e.g., the channel 35) is closed (e.g., when the piezoelectric bicrystalline wafer or bimetallic strip bends downward). Figure 11 (a) shows); and when the piezoelectric bicrystalline wafer or bimetallic sheet is bent upwards or straightened, the area where the extrusion port 32 is located (e.g., channel 35) is opened (e.g., as shown in (a)). Figure 11 (b) shown).

[0085] Alternatively, the sheet switch 44 can also be made of a thermally expanding metal resistor or shape memory alloy, and its fixing method is the same as above. The difference is that this type of sheet switch 44 may only require one piece.

[0086] By placing the sheet switch 44 outside the material cavity 31, the influence of the voltage or temperature when controlling the sheet switch 44 on the molten material in the material cavity 31 can be isolated, thereby enabling more precise control of the temperature of the molten material and the sheet switch.

[0087] In some embodiments, such as Figure 12 As shown, the 3D printing apparatus 2 may further include a feeding system 5. The feeding system 5 is connected to the material cavity 31 via the material inlet 33, and is used to heat the molten material and transport the molten material into the material cavity 31. This feeding system 5 can be, for example, a continuously variable flow feeding device; however, this embodiment does not specifically limit the form of the feeding system 5. For example, the feeding system 5 can be a screw-type feeding system, a pneumatic feeding system, or a piston-type feeding system.

[0088] When the feeding system 5 is a pneumatic feeding system, such as Figure 12 As shown, it is usually necessary to set up a pneumatic conveying pipeline 51 and a material storage tank 52 connected to the pneumatic conveying pipeline 51 for the pneumatic feeding system 5.

[0089] In view of this, the material cavity 31 also contains pressure generated by the aforementioned pressurized gas. This pressure may have a certain impact on the movement of the aforementioned transmission member 45. For example, when the sheet switch 44 is located outside the material cavity 31, and the sheet switch 44 drives the transmission member 45 to move downward to close the corresponding extrusion port 32 area (e.g., channel 35), this pressure will give the transmission member 45 upward resistance. This may require the switch assembly 4 to apply a larger force to the transmission member 45 to achieve the shutdown, thus causing some difficulty in the on / off control of the switch assembly 4.

[0090] To solve the above problems, such as Figure 12 As shown, the 3D printing apparatus 2 in this embodiment further includes a control chamber 6. Multiple sheet switches 44 are located within the control chamber 6, and the pneumatic delivery pipeline 51 can be configured to communicate with the gas in the control chamber 6. This configuration allows the pressure of the pressurized gas to also act on the space where the sheet switches 44 and the transmission component 45 are located, thereby achieving pressure balance with the pressure of the extruded molten material. Thus, when the sheet switches 44 drive the transmission component 45 to move up and down to control the on / off state of the switch assembly 4, it is unaffected by the force of the extruded molten material, ensuring control accuracy and reducing power consumption in the on / off control.

[0091] It should be noted that the above description uses the pneumatic feeding system 5 of the 3D printing device 2 as an example, but the embodiments of this application are not limited to this. As long as a pneumatic conveying pipeline 51 can be used to form a pressure balance between the material storage tank 52 and the control chamber 6, it is acceptable. For example, the 3D printing device 2 can still use other feeding methods such as screws. Then, a pneumatic conveying pipeline 51 can be introduced to connect the material storage tank 52 on the feeding route and the control chamber 6 where the switching components are located, thereby forming a pressure balance between the two and reducing the difficulty and power consumption of the on / off control of the switching components in the control chamber 6.

[0092] It is understood that the embodiments of this application are not limited to the structure of the switch assembly 4 necessarily including the sheet switch 44, and it may also be other structural forms. For example, the switch assembly 4 may include one or more of the following switches: motor-controlled switch, pneumatic-controlled switch, and hydraulic-controlled switch.

[0093] The switch controlled by the motor can be the motor shaft or a transmission component driven by the motor shaft. Since the motor shaft can move linearly when the motor is energized, simply controlling the forward and reverse rotation of the motor is sufficient to control whether the motor shaft or the transmission component is in contact with or away from the area where the extrusion port 32 is located. This method is particularly suitable for controlling the on / off state of an extrusion port 32 that includes multiple channels 35, especially when the diameter of the channels 35 is large and the number of channels is small.

[0094] A pneumatic or hydraulically controlled switch can be a pneumatic or hydraulically controlled piston, or a transmission component driven by the piston. For example... Figure 13 The diagram illustrates one possible implementation of the switch assembly 4, which includes a switch controlled by pneumatic or hydraulic pressure. It should be understood that... Figure 13 The example shown only includes a switch assembly that is pneumatically or hydraulically controlled. Other pneumatically or hydraulically controlled switches are configured in the same or similar ways as illustrated.

[0095] See Figure 13 The switching assembly 4 may include a chamber 46 and a piston 47. The chamber 46 is located above the material container 31 and may have a first interface 461 and a second interface 462 for external connection, such as connecting to a pneumatic or hydraulic device. The piston 47 is located in the chamber 46. When the first interface is the inlet and the second interface is the outlet, the piston 47 can move upwards; when the first interface is the outlet and the second interface is the inlet, the piston can move downwards to control the on / off state of the area where the extrusion port 32 is located. It is understood that the inlet pressure is greater than the outlet pressure. In some embodiments, a transmission member 48 may also be provided below the piston 47. When the piston 47 moves up and down, it can drive the transmission member 48 to move up and down together to achieve on / off control. Of course, the transmission member 48 can be part of the piston 47, that is, the transmission member 48 and the piston 47 are integrally formed. This application embodiment does not limit the presence or absence of the transmission member 48, as long as the up and down movement of the piston 47 can achieve the on / off control of the switching assembly 4.

[0096] In some embodiments, the plurality of channels mentioned above and the plurality of switches corresponding to each of the plurality of channels can be replaced by a plurality of printheads, which can be arranged closely together to achieve the functions mentioned above.

[0097] The above text combined Figures 1-13 This document describes in detail embodiments of the 3D printing apparatus of this application. The following is in conjunction with… Figure 14 and Figure 15 This document describes embodiments of the method described in this application. It should be understood that this method can be performed by the 3D printing apparatus mentioned above; therefore, any parts not described in detail can be found above.

[0098] See Figure 14 The 3D printing method provided in this application embodiment may include steps S1410 and S1420.

[0099] In step S1410, the molten material is conveyed to the extrusion port to print the current printing layer.

[0100] In step S1420, during the printing of the current printing layer, the switching component is used to control the on / off state of the area where the extrusion port is located, so as to form multiple sub-extrusion ports with continuously adjustable widths.

[0101] Optionally, multiple sub-extrusion ports are used to print multiple partitions in the current printing layer simultaneously. During the printing process of multiple partitions using multiple sub-extrusion ports, the width of each sub-extrusion port changes with the outline of the partition corresponding to each sub-extrusion port, thereby filling the partition corresponding to each sub-extrusion port with molten material in one go.

[0102] Optionally, the multiple partitions include a first partition and a second partition, and the multiple sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. Figure 14 The method also includes: printing a first sub-extrusion port and a second sub-extrusion port respectively, wherein the first sub-extrusion port and the second sub-extrusion port have mutually isolated areas and mutually connected areas, and when printing the mutually connected areas, the on / off control causes the first sub-extrusion port and the second sub-extrusion port to merge into a single sub-extrusion port.

[0103] Optionally, the switching assembly includes multiple sheet switches. Figure 14 The method also includes: using multiple sheet switches to deform under the control of temperature and / or voltage to control the on / off state of the area where the extrusion port is located.

[0104] Optionally, multiple sheet switches are disposed inside the material cavity and above the area where the extrusion port is located.

[0105] Optionally, multiple sheet switches are disposed outside the material cavity, and the multiple sheet switches are respectively connected to multiple transmission components, and the multiple transmission components control the on / off state of the area where the extrusion port is located.

[0106] Optionally, Figure 14 The method further includes: using a pneumatic conveying pipeline to deliver pressurized gas to the control chamber and the material storage tank, wherein the plurality of plate switches are located in the control chamber, and the material storage tank is connected to the material cavity of the material extrusion section.

[0107] Optionally, the multiple chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

[0108] Optionally, the switching assembly includes one or more of the following switches: motor-controlled switch, pneumatically controlled switch, and hydraulically controlled switch.

[0109] See Figure 15 Another 3D printing method provided in this application embodiment may include steps S1510 and S1520.

[0110] In step S1510, the molten material is conveyed to the extrusion port to print the current printing layer using multiple channels in the extrusion port, wherein the material extruded from adjacent channels in the multiple channels is fused together in the current printing layer.

[0111] In step S1520, during the printing of the current printing layer, the switching assembly is used to control the opening and closing of multiple channels to form multiple sub-extrusion ports with continuously adjustable widths.

[0112] Optionally, during the printing of the current printing layer, multiple sub-extrusions are used to print multiple partitions in the current printing layer simultaneously. The width of each sub-extrusion varies with the outline of the partition corresponding to each sub-extrusion, thereby filling the partition corresponding to each sub-extrusion with molten material in one go.

[0113] Optionally, the multiple partitions include a first partition and a second partition, and the multiple sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. Figure 15 The method also includes: printing a first sub-extrusion port and a second sub-extrusion port respectively, wherein the first sub-extrusion port and the second sub-extrusion port have mutually isolated areas and mutually connected areas, and when printing the mutually connected areas, the on / off control of the switch assembly causes the first sub-extrusion port and the second sub-extrusion port to merge into a single sub-extrusion port.

[0114] Optionally, the switching assembly includes multiple sheet switches corresponding one-to-one with multiple channels. Figure 15 The method also includes: using multiple sheet switches to deform under the control of temperature and / or voltage to control the on / off state of multiple channels.

[0115] Optionally, multiple sheet switches are disposed inside the material cavity and above multiple channels.

[0116] Optionally, multiple sheet switches are disposed outside the material cavity, and the multiple sheet switches are respectively connected to multiple transmission components, and the multiple transmission components control the opening and closing of multiple channels.

[0117] Optionally, Figure 15 The method further includes: using a pneumatic conveying pipeline to deliver pressurized gas to the control chamber and the material storage tank, wherein the plurality of plate switches are located in the control chamber, and the material storage tank is connected to the material cavity of the material extrusion section.

[0118] Optionally, multiple channels are arranged in an alternating pattern.

[0119] Optionally, the multiple chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

[0120] Optionally, the switching assembly includes one or more of the following switches: motor-controlled switch, pneumatically controlled switch, and hydraulically controlled switch.

[0121] Those skilled in the art will recognize that the units and algorithm steps of the various examples described in conjunction with the embodiments disclosed herein can be implemented in electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are implemented in hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of this application.

[0122] In the embodiments provided in this application, it should be understood that the disclosed system can be implemented in other ways. For example, the device embodiments described above are merely illustrative. For instance, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. For example, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection shown or discussed may be through some interfaces, or indirect coupling or communication connection between devices or units, and may be electrical, mechanical, or other forms.

[0123] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0124] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0125] The above description is merely a specific embodiment of this application, but the scope of protection of this application is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in this application should be included within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A 3D printing device, characterized in that, The device includes: The material extrusion section includes a material cavity and an extrusion port communicating with the material cavity. The material cavity is used to contain molten material, and the extrusion port is used to extrude the molten material to the current printing layer. A switching assembly, coupled to the extrusion port, is used to control the on / off state of the area where the extrusion port is located, so as to form multiple sub-extrusion ports with continuously adjustable widths. The multiple sub-extrusion ports are used to print multiple partitions in the current printing layer at the same time. During the printing of the multiple partitions using the multiple sub-extrusion ports, the width of each of the multiple sub-extrusion ports changes with the outline of the partition corresponding to each sub-extrusion port, thereby filling the molten material into the partition corresponding to each sub-extrusion port in one go. The plurality of partitions include a first partition and a second partition, and the plurality of sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. The first sub-extrusion port and the second sub-extrusion port are respectively used to print the first partition and the second partition. The first partition and the second partition have mutually isolated areas and mutually connected areas. When printing the mutually connected areas, the on / off control of the switch assembly causes the first sub-extrusion port and the second sub-extrusion port to merge into one sub-extrusion port. The switching assembly includes multiple sheet switches, which deform under the control of temperature and / or voltage to control the on / off state of the area where the extrusion port is located.

2. The apparatus according to claim 1, characterized in that, The plurality of sheet switches are disposed inside the material cavity and above the area where the extrusion port is located.

3. The apparatus according to claim 1, characterized in that, The plurality of sheet switches are disposed outside the material cavity. The plurality of sheet switches are respectively connected to a plurality of transmission components, and the plurality of transmission components control the on / off state of the area where the extrusion port is located.

4. The apparatus according to claim 3, characterized in that, The device further includes: A control chamber, in which the plurality of sheet switches are located; A material storage tank, connected to the material cavity of the material extrusion section; and The pneumatic conveying pipeline is connected to both the material storage tank and the control chamber.

5. The apparatus according to claim 1, characterized in that, The plurality of chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

6. A 3D printing apparatus, characterized in that, include: The material extrusion section includes a material cavity and an extrusion port. The material cavity is used to contain molten material, and the extrusion port includes a plurality of channels communicating with the material cavity. The plurality of channels are used to extrude the molten material to the current printing layer, and the materials extruded from adjacent channels in the plurality of channels are fused together in the current printing layer. A switching assembly, coupled to the plurality of channels, is used to control the opening and closing of the plurality of channels to form a plurality of sub-extrusion ports with continuously adjustable widths; The plurality of sub-extrusion ports are used to print multiple partitions in the current printing layer simultaneously. During the printing process of the multiple partitions using the plurality of sub-extrusion ports, the width of each sub-extrusion port changes with the outline of the partition corresponding to each sub-extrusion port, thereby filling the molten material into the partition corresponding to each sub-extrusion port in one go. The plurality of partitions include a first partition and a second partition, and the plurality of sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. The first sub-extrusion port and the second sub-extrusion port are respectively used to print the first partition and the second partition. The first partition and the second partition have mutually isolated areas and mutually connected areas. When printing the mutually connected areas, the on / off control of the switch assembly causes the first sub-extrusion port and the second sub-extrusion port to merge into one sub-extrusion port. The switching assembly includes multiple sheet switches that correspond one-to-one with the plurality of channels. The multiple sheet switches deform under the control of temperature and / or voltage, thereby controlling the opening and closing of the plurality of channels.

7. The apparatus according to claim 6, characterized in that, The plurality of sheet switches are disposed inside the material cavity and above the plurality of channels.

8. The apparatus according to claim 6, characterized in that, The plurality of sheet switches are disposed outside the material cavity, and are respectively connected to a plurality of transmission components, which control the opening and closing of the plurality of channels.

9. The apparatus according to claim 8, characterized in that, The device further includes: A control chamber, in which the plurality of sheet switches are located; A material storage tank, connected to the material cavity of the material extrusion section; and The pneumatic conveying pipeline is connected to both the material storage tank and the control chamber.

10. The apparatus according to claim 6, characterized in that, The multiple channels are arranged in an alternating pattern.

11. The apparatus according to claim 6, characterized in that, The plurality of chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

12. A 3D printing method, characterized in that, The method includes: The molten material is fed to the extrusion port to print the current layer; During the printing of the current printing layer, a switching component is used to control the on / off state of the area where the extrusion port is located, so as to form multiple sub-extrusion ports with continuously adjustable widths. The multiple sub-extrusion ports are used to print multiple partitions in the current printing layer at the same time. During the printing of the multiple partitions using the multiple sub-extrusion ports, the width of each sub-extrusion port changes with the outline of the partition corresponding to each sub-extrusion port, thereby filling the molten material into the partition corresponding to each sub-extrusion port in one go. The plurality of partitions include a first partition and a second partition, and the plurality of sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. The first partition and the second partition are printed using the first sub-extrusion port and the second sub-extrusion port, respectively. The first partition and the second partition have mutually isolated areas and mutually connected areas. When printing the mutually connected areas, the on / off control causes the first sub-extrusion port and the second sub-extrusion port to merge into a single sub-extrusion port. The switching assembly includes multiple sheet switches, which deform under the control of temperature and / or voltage to control the on / off state of the area where the extrusion port is located.

13. The method according to claim 12, characterized in that, The plurality of sheet switches are disposed inside the material cavity and above the area where the extrusion port is located.

14. The method according to claim 12, characterized in that, The plurality of sheet switches are disposed outside the material cavity. The plurality of sheet switches are respectively connected to a plurality of transmission components, and the plurality of transmission components control the on / off state of the area where the extrusion port is located.

15. The method according to claim 14, characterized in that, The method further includes: Pressurized gas is delivered to the control chamber and the material storage tank via a pneumatic delivery pipeline. The plurality of plate switches are located in the control chamber, and the material storage tank is connected to the material cavity of the material extrusion section.

16. The method according to claim 12, characterized in that, The plurality of chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

17. A 3D printing method, characterized in that, include: Molten material is conveyed to an extrusion port to print the current printing layer using multiple channels in the extrusion port, wherein the material extruded from adjacent channels in the multiple channels is fused together in the current printing layer. During the printing of the current printing layer, the multiple channels are controlled by a switching component to form multiple sub-extrusion ports with continuously adjustable widths. The multiple sub-extrusion ports are used to print multiple partitions in the current printing layer simultaneously. The width of each sub-extrusion port varies with the outline of the partition corresponding to each sub-extrusion port, thereby filling the partition corresponding to each sub-extrusion port with the molten material in one go. The plurality of partitions include a first partition and a second partition, and the plurality of sub-extrusion ports include a first sub-extrusion port and a second sub-extrusion port. The first partition and the second partition are printed using the first sub-extrusion port and the second sub-extrusion port, respectively. The first partition and the second partition have mutually isolated areas and mutually connected areas. When printing the mutually connected areas, the on / off control of the switch assembly causes the first sub-extrusion port and the second sub-extrusion port to merge into a single sub-extrusion port. The switching assembly includes multiple sheet switches that correspond one-to-one with the plurality of channels. The plurality of sheet switches are deformed under the control of temperature and / or voltage to control the opening and closing of the plurality of channels.

18. The method according to claim 17, characterized in that, The plurality of sheet switches are disposed inside the material cavity and above the plurality of channels.

19. The method according to claim 17, characterized in that, The plurality of sheet switches are disposed outside the material cavity. The plurality of sheet switches are respectively connected to a plurality of transmission components, and the plurality of transmission components control the opening and closing of the plurality of channels.

20. The method according to claim 19, characterized in that, The method further includes: Pressurized gas is delivered to the control chamber and the material storage tank via a pneumatic delivery pipeline. The plurality of plate switches are located in the control chamber, and the material storage tank is connected to the material cavity of the material extrusion section.

21. The method according to claim 17, characterized in that, The multiple channels are arranged in an alternating pattern.

22. The method according to claim 17, characterized in that, The plurality of chip switches include one or more of the following: piezoelectric bicrystalline wafers, bimetallic strips, thermally expanding metal resistors, and shape memory alloys.

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