CN113492528A

CN113492528A - Apparatus for 3D printing and control method thereof

Info

Publication number: CN113492528A
Application number: CN202010264834.9A
Authority: CN
Inventors: 黄卫东
Original assignee: Suzhou Meimeng Machinery Co ltd
Current assignee: Suzhou Meimeng Machinery Co ltd
Priority date: 2020-04-03
Filing date: 2020-04-03
Publication date: 2021-10-12
Anticipated expiration: 2040-04-03
Also published as: CN113492528B

Abstract

An apparatus for 3D printing and a control method thereof are provided. The apparatus comprises: the inner surface of the shell forms a cylindrical inner cavity, the shell is provided with a plurality of openings extending along the axial direction of the cylindrical inner cavity, and the widths of different openings are different; the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, the area which is not shielded by the shielding part in the opening forms a discharge hole, the rotary shaft can rotate around the axis of the cylindrical inner cavity to continuously change the area of the shielding part for shielding the opening, so that the length of the discharge hole is continuously changed, and the shell can move relative to the rotary shaft to ensure that different openings in the plurality of openings are shielded by the shielding part to form the discharge hole; and the feed inlet is communicated with a feed delivery channel enclosed by the outer end surface of the shielding part and the inner surface of the shell. The discharge port is designed to be the discharge port with the continuously adjustable length, the width of the discharge port can be switched, and the 3D printing efficiency and precision can be considered to be possible.

Description

Apparatus for 3D printing and control method thereof

Technical Field

The present application relates to the field of 3D printing, and more particularly, to an apparatus for 3D printing and a control method thereof.

Background

Fused Deposition Modeling (FDM) is a common 3D printing technique. FDM techniques generally require heating a material to a molten state (or semi-flow state) and extruding the molten material from a discharge port (or extrusion port) of a 3D print head, where the material is deposited layer by layer on a printing platform to form a 3D object.

The discharge port of the conventional 3D print head is generally a nozzle having a fixed shape. When the printing precision requirement of the object is higher, a nozzle with a smaller caliber is usually selected, the material extrusion amount of the nozzle in unit time is less, and the printing efficiency is lower; when the printing efficiency requirement of the object is high, a nozzle with a larger caliber is usually selected, the shape of the object printed by the nozzle is rough, and the printing precision is low. Therefore, the traditional 3D printing head cannot give consideration to both efficiency and precision.

The 3D printing technology is mainly oriented to industrial production in the future, and for industrial products, the efficiency and the precision are equally important.

Disclosure of Invention

The present application provides an apparatus for 3D printing and a control method thereof, which make it possible to compromise efficiency and accuracy of 3D printing.

In a first aspect, there is provided an apparatus for 3D printing, comprising: the inner surface of the shell forms a cylindrical inner cavity, a plurality of openings extending along the axial direction of the cylindrical inner cavity are arranged on the shell, and the width of different openings in the plurality of openings is different; the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, an area which is not shielded by the shielding part in the opening forms a discharge port, the rotary shaft can rotate around the axis of the cylindrical inner cavity to continuously change the area of the shielding part for shielding the opening so as to continuously change the length of the discharge port, and the shell can move relative to the rotary shaft so that different openings in the plurality of openings are shielded by the shielding part to form the discharge port; and the feed inlet is communicated with a feed delivery channel enclosed by the outer end surface of the shielding part and the inner surface of the shell.

In a second aspect, there is provided a method of controlling an apparatus for 3D printing, the apparatus for 3D printing including: the inner surface of the shell forms a cylindrical inner cavity, a plurality of openings extending along the axial direction of the cylindrical inner cavity are arranged on the shell, and the width of different openings in the plurality of openings is different; the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, an area which is not shielded by the shielding part in the opening forms a discharge hole, the rotary shaft can rotate around the axis of the cylindrical inner cavity, and the shell can move relative to the rotary shaft; the feed inlet is communicated with a material conveying channel enclosed by the outer end surface of the shielding part and the inner surface of the shell; the control method comprises the following steps: controlling the shell to move relative to the rotating shaft, so that different openings in the plurality of openings are shielded by the shielding part to form the discharge hole; the rotary shaft is controlled to rotate around the axis of the cylindrical inner cavity so as to continuously change the area of the opening shielded by the shielding part, and thus the length of the discharge hole is continuously changed.

In a third aspect, a computer-readable storage medium is provided, on which instructions for executing the control method according to the second aspect are stored.

In a fourth aspect, a computer program product is provided, comprising instructions for performing the control method according to the second aspect.

The discharge port is designed into the discharge port with continuously adjustable length, the width of the discharge port can be switched, the discharge port enables the efficiency and the precision of 3D printing to be considered, and the discharge port is more suitable for 3D printing.

Drawings

Fig. 1 is a schematic diagram of the overall structure of a conventional 3D printing apparatus.

Fig. 2 is a schematic structural view of a conventional 3D printhead.

Fig. 3a is an exemplary diagram of a print area of a layer to be printed.

FIG. 3b is an exemplary diagram of the arrangement of the passes.

Fig. 4 is a perspective view of an apparatus for 3D printing according to an embodiment of the present application.

Fig. 5 is a schematic view of the internal structure of the apparatus shown in fig. 4.

Fig. 6 is a diagram illustrating an example of a printing process of the apparatus shown in fig. 4.

Fig. 7 is a schematic plan view of the printing process shown in fig. 6.

Fig. 8 is a comparison graph of the printing mode provided by the embodiment of the present application and the printing effect of the conventional printing mode.

Fig. 9 is an exemplary diagram of a pass switching manner in a conventional 3D printing process.

Fig. 10 is a perspective view of an apparatus for 3D printing according to another embodiment of the present application.

Fig. 11 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 12 is a structural view of a housing in the apparatus shown in fig. 11.

Fig. 13 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 14 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 15 is a structural view of a housing in the apparatus shown in fig. 14.

Fig. 16 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 17 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 18 and 19 are structural views of a housing in the apparatus shown in fig. 17.

Fig. 20 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

FIG. 21 is a side view of an open channel in an apparatus for 3D printing provided by yet another embodiment of the present application.

Fig. 22 is a structural view of a housing in the apparatus shown in fig. 23.

Fig. 23 is a perspective view of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 24 is a bottom view of the apparatus shown in fig. 5.

Fig. 25 is a side view of an apparatus for 3D printing provided in another embodiment of the present application.

Fig. 26 is a bottom view of the device shown in fig. 25.

Fig. 27 is a structural view of a spindle provided in one embodiment of the present application.

Fig. 28 is a structural view of a spindle according to another embodiment of the present application.

Fig. 29 is a block diagram of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 30 is a block diagram of an apparatus for 3D printing according to still another embodiment of the present application.

Fig. 31 is an exemplary view of a feeding device provided in an embodiment of the present application.

Fig. 32 is a schematic flowchart of a control method of an apparatus for 3D printing provided in an embodiment of the present application.

Detailed Description

For ease of understanding, a brief description of a conventional 3D printing apparatus will be given.

As shown in fig. 1, the conventional 3D printing apparatus 1 generally includes a feeding device 11, a 3D printing head 12, a printing platform 13, and a control device 14 (the above structural division is only an example, and actually, other structural division may be adopted, for example, the control device and/or the feeding device 11 may be a part of the 3D printing head 12).

The feeding device 11 may be connected to a wire disc 15. During the actual printing process, the feeding device 11 may take filamentary material from the filament tray 15 and deliver the filamentary material to the 3D print head 12. The materials used in the 3D printing process are typically thermoplastic materials such as high molecular weight polymers, low melting point metals, and other materials that can be formulated into a flowable paste (e.g., ceramic paste, high melting point metal powder mixture, cement, etc.).

As shown in fig. 2, the 3D print head 12 generally includes a feeding passage 121, a discharging port 122, and a temperature control device 123. The temperature control device 123 is generally disposed outside the material conveying channel 121, and is used for heating the material conveyed to the material conveying channel 121 by the feeding device 11 to a molten state. The temperature control device 123 may be, for example, a heating device. The discharge port 122 may extrude the material in a molten state onto the printing platform 13, and therefore, the discharge port 122 may also be referred to as an extrusion port.

Control device 14 may be used to control 3D print head 12 to print the article layer by layer. In the process of printing each layer, the 3D print head 12 may be controlled to print all the printing areas of the layer to be printed (i.e. all the areas surrounded by the cross-sectional outline of the layer to be printed) completely according to the preset printing path.

The overall process of conventional 3D printing is roughly as follows:

prior to printing the item, a 3D model of the item may be created using modeling software. The modeling software may be, for example, Computer Aided Design (CAD) software. And then, carrying out layering processing on the created 3D model, dividing the 3D model into a plurality of layers to be printed, and obtaining layering data of each layer to be printed. By layering the 3D model, the printing process of the 3D object is decomposed into a plurality of 2D printing processes, and the printing process of each layer to be printed is similar to the planar 2D printing process. After obtaining the hierarchical data of each layer to be printed, the control device 14 may control the 3D print head 12 to move along a certain printing path according to the hierarchical data of each layer to be printed, and in the moving process, extrude the material in the molten state onto the printing platform 13 through the discharge port 122, and print or fill the printing area of each layer to be printed. And when all the layers to be printed of the object are printed, solidifying the material layer by layer to form the 3D object.

For ease of understanding, the following describes in detail a printing process of a layer to be printed by a conventional 3D printing apparatus, taking fig. 3a and 3b as an example.

Referring to fig. 3a and 3b, the printing area of the layer to be printed is area 31, and the cross-sectional outline of area 31 is cross-sectional outline 32.

To complete the printing of region 31, region 31 is typically divided into a plurality of closely spaced passes (pass) based on cross-sectional profile 32, such as pass A shown in FIG. 3b₁Pass A₂₅。

During the printing process, the control device 14 controls the z coordinate of the 3D printing head 12 to be kept unchanged, and controls the 3D printing head 12 to completely print all passes in a certain sequence, for example, sequentially print pass a in a parallel reciprocating linear path₁-A₂₅。

In pass A₁For example, the control device 14 may move the 3D printing head 12 to above the position point p1 shown in fig. 3a, then control the 3D printing head 12 to move from above the position point p1 to above the position point p2, and extrude the material in the molten state to pass a through the discharge port 122 during the moving process₁Thus, for pass A₁And printing is carried out in a similar way in other passes, and details are not repeated here. After all the passes of printing are finished, the printing process of the layer to be printed is finished, and the 3D printing head 12 or the working platform 13 may be controlled to move along the z-axis direction to prepare for printing the next layer.

The discharge opening 122 of the 3D print head 12 is usually designed as a fixed-shape nozzle, and common nozzle shapes include a round hole, a square hole, or a slightly deformed hole with a constant diameter and a special shape. The orifice diameter of the nozzle is usually about 1mm, and the orifice diameter is usually 0.4 mm. When the printing precision requirement of the object is higher, a nozzle with a smaller caliber is usually selected, the material extrusion amount of the nozzle in unit time is less, and the printing efficiency is lower; when the printing efficiency requirement of the object is high, a nozzle with a larger caliber is usually selected, the shape of the object printed by the nozzle is rough, and the printing precision is low. Therefore, the traditional 3D printing head cannot give consideration to both the efficiency and the precision of 3D printing. The formation process of this design of the discharge opening of the 3D print head is analyzed below.

The 3D printing technology is a more advanced manufacturing technology developed on the basis of the 2D printing technology. Before 3D printing, layered processing is generally required to be performed on a 3D model of an article to be printed, and after the layered processing, it is equivalent to decompose a printing process of the 3D article into a plurality of 2D printing processes, that is, the printing process of each layer can be regarded as a one-time flat printing process. Therefore, the conventional 3D printing apparatus follows many design concepts of the 2D printing apparatus. Most obviously, the discharge port of the 2D printing head is generally designed as a nozzle with a fixed shape, and the discharge port of the 3D printing head follows the design of the discharge port of the 2D printing head, and is also designed as a nozzle with a fixed shape. As described above, such nozzle design results in a failure of the 3D print head to achieve both efficiency and precision, which is a key obstacle hindering the development of 3D printing technology.

Therefore, there is a need to provide an apparatus more suitable for 3D printing without being bound by the design concept of the 2D printing apparatus.

The following describes in detail an apparatus for 3D printing provided in an embodiment of the present application. It should be noted that the apparatus for 3D printing may refer to a 3D printing head, and may also refer to an entire 3D printer or a 3D printing system.

As shown in fig. 4, the apparatus 4 for 3D printing provided by the embodiment of the present application may include a housing 41 and a rotating shaft 42.

The inner surface of the housing 41 defines a cylindrical cavity 45 (or cylindrical cavity). The housing 41 is provided with a plurality of openings 46 extending in the axial direction of the cylindrical cavity 45. By way of example and not limitation, in fig. 4, 2 openings 46 are shown: openings 46(1) and 46 (2).

The opening 46 may be a slit having a large aspect ratio. For example, the width of the opening 46 may take any value from 0.01mm to 5 mm.

At least some of the plurality of openings 46 have different widths. For example, the width of different openings 46 of the plurality of openings 46 may all be different. For another example, the width of some of the openings 46 is different, and the width of some of the openings 46 is the same. As an example, in fig. 4, the width of the opening 46(1) is smaller than the width of the opening 46 (2). Opening 46(1) may form a spout of smaller width, and opening 46(2) may form a spout of larger width. The manner in which the outlet is formed will be described below and will not be described in detail here.

The length of each opening 46 in the plurality of openings 46 may be the same, different, or not all the same.

In fig. 4, the openings 46(1) and 46(2) may be seamlessly connected, in which case, the openings 46(1) and 46(2) may be collectively referred to as variable-gauge slot openings.

It should be noted that fig. 4 is only an example and not a limitation. For simplicity of illustration, the 2 openings 46(1) and 46(2)) are schematically illustrated in the drawings, but the present application is not limited thereto. For example, a greater number of openings 46 (e.g., openings 46(1), 46(2), …, 46(n)) may be provided in housing 41. As an example, 2, 3, 4 or 6 openings 46 may be provided in the housing 41. Various numbers of openings 46 can be designed according to actual needs (for example, an odd number of openings 46 can be designed, and an even number of openings 46 can also be designed).

The plurality of openings 46 may be disposed at various positions on the housing 41. As shown in fig. 4, 10, 14, 15, or 16, the plurality of openings 46 may be disposed on the housing 41 in such a manner that the plurality of openings 46 are arranged on the housing 41 in the axial direction of the cylindrical inner cavity 45. As also shown in fig. 11, 12, or 19, the plurality of openings 46 may be disposed on the housing 41 in such a manner that the plurality of openings 46 are arranged on the housing 41 in the circumferential direction of the cylindrical inner cavity 45. For another example, the plurality of openings 46 may be disposed on the housing 41 in a manner that the plurality of openings 46 are arranged on the housing 41 in a circumferential direction of the cylindrical cavity 45 and in an axial direction of the cylindrical cavity 45 (not shown).

In some embodiments, the housing 41 may be a unitary housing, i.e., an integrally formed housing, as shown in fig. 4, 10, 11, 12, or 13.

In other embodiments, the housing 41 may be a separate housing, i.e., the outer wall of the housing 41 may include multiple separable parts, or the outer wall of the housing 41 may be formed by splicing multiple separable parts.

As shown in fig. 14, 15, 17, 18 or 19, the outer wall of the housing 41 may include a first portion 411 and a second portion 412 that are separable. The first portion 411 and the second portion 412 have complementary structures.

In some embodiments, the outer wall of the housing 41 may also be combined from three or more separable portions. For example, the outer wall of the housing 41 includes a first portion, a second portion, a third portion and a fourth portion which are separable, and edges of the four portions are spliced with each other to form the outer wall of the housing 41.

The spindle 42 is rotatable about the axis of the cylindrical bore 45. As shown in fig. 5, the rotary shaft 42 has a shielding portion 47 provided at the shaft end thereof, the shielding portion 47 is located in the cylindrical inner cavity 45 to shield an area in the opening 46, an area in the opening 46 not shielded by the shielding portion 47 forms the discharge port 48, and the rotary shaft 42 is rotatable about the axis of the cylindrical inner cavity 45 to continuously change the area in which the shielding portion 47 shields the opening 46, thereby continuously changing the length of the discharge port 48. The manner in which the blocking portion 47 of the rotary shaft 42 and the opening 46 of the housing 41 form the discharge port 48 will be described in detail with reference to specific embodiments, and will not be described in detail here.

The housing 41 is movable relative to the spindle 42 such that different ones 46 of the plurality of openings 46 provided in the housing 41 are blocked by the blocking portion 47 to form the discharge port 48.

Alternatively, the housing 41 is movable relative to the rotary shaft 42 so that different openings 46 of the plurality of openings 46 provided in the housing 41 are moved to the position of the discharge port 48, and are shielded by the shielding portion 47 to form the discharge port 48.

Alternatively, the housing 41 is movable relative to the spindle 42 to communicate different ones 46 of the plurality of openings 46 provided in the housing 41 with the outlet 48 (i.e., to effect switching between the different openings 46).

Movement of the housing 41 relative to the spindle 42 causes one opening 46 of the plurality of openings 46 provided in the housing 41 to move to the location of the spout 48, while the remaining openings 46 are moved to a location other than the spout. That is, the movement of the housing 41 relative to the shaft 42 causes only one opening 46 to be located at the outlet 48 at a time.

The opening moves to the position of the spout, indicating that the opening is in communication with the spout. The opening is moved to a position other than the spout, indicating that the opening is not in communication with the spout.

The opening 46 shown in fig. 5, 6, 7, 25, 26, and 29 indicates one of the plurality of openings 46 provided in the housing 41 that is moved to the position of the discharge port 48.

For the sake of simplicity of drawing, only one opening 46 that is shifted to the position of the discharge port 48 among the plurality of openings 46 provided in the housing 41 is schematically shown in fig. 5, 6, 7, 25, 26, and 29.

In practice, one of the openings 46 that needs to be opened can be moved to the location of the spout. For example, the opening 46 that needs to be opened may be an opening having an opening width that meets the printing accuracy requirements of the 3D object.

Printing of 3D objects has different printing accuracy requirements. The device 4 provided by the present application can move one opening 46, which meets the printing precision requirement, of the plurality of openings 46 provided on the housing 41 to the position of the discharging hole 48 through the movement of the housing 41 relative to the rotating shaft 42 according to the printing precision requirement of the 3D object, so as to be shielded by the shielding portion 47 to form the discharging hole 48.

As an example, assuming that the opening 46 having the width W1 needs to be opened according to the printing accuracy requirement, the housing 41 is moved relative to the rotating shaft 42 so that the opening 46 having the width W1 provided on the housing 41 is moved to the position of the discharge port 48, and is shielded by the shielding portion 47 to form the discharge port 48 (referred to as the discharge port 48 (1)).

As another example, assuming that the opening 46 having the width W2 needs to be opened according to the printing accuracy requirement, the housing 41 is moved relative to the rotating shaft 42 so that the opening 46 having the width W2 provided on the housing 41 is moved to the position of the discharge port 48, and is shielded by the shielding portion 47 to form the discharge port 48 (referred to as the discharge port 48 (2)). The width of the discharging hole 48(2) is different from that of the discharging hole 48(1), that is, the discharging hole 48(2) and the discharging hole 48(1) can satisfy different 3D printing precisions.

In practical applications, the openings 46 with different widths can be switched according to the printing precision requirement.

The housing 41 is movable relative to the spindle 42. For example, the housing 41 may translate axially along the cylindrical cavity 45 with respect to the rotation axis 42; for another example, the housing 41 may rotate about the axis of the cylindrical cavity 45 relative to the spindle 42; for another example, the housing 41 can be either translated relative to the rotating shaft 42 along the axial direction of the cylindrical cavity 45 or rotated relative to the rotating shaft 42 about the axis of the cylindrical cavity 45.

Specifically, the manner in which the housing 41 moves relative to the spindle 42 may be determined based on the manner in which the plurality of openings 46 are provided on the housing 41.

For example, regarding the position arrangement of the plurality of openings 46 as shown in fig. 4, 10, 14, 15 or 16, that is, the plurality of openings 46 are arranged along the axial direction of the cylindrical inner cavity 45, the housing 41 can translate along the axial direction of the cylindrical inner cavity 45, so that the opening 46 needing to be opened in the plurality of openings 46 is moved to the position of the discharge port 48, and is shielded by the shielding portion 47 to form the discharge port 48.

For another example, as shown in fig. 11, 12 or 19, the plurality of openings 46 are arranged in a circumferential direction of the cylindrical cavity 45, and the housing 41 is rotatable around the axis of the cylindrical cavity 45, so that the opening 46 to be opened in the plurality of openings 46 is moved to the position of the discharge hole 48, and is shielded by the shielding portion 47 to form the discharge hole 48.

As an example, assuming that the position of the discharge hole 48 is regarded as the front surface of the rotary shaft 42, the housing 41 is rotated around the axis of the cylindrical inner cavity 45, so that the opening 46 to be opened is moved to the front surface of the rotary shaft 42, and at the same time, the remaining openings 46 are moved to the side surface or the back surface of the rotary shaft 42.

For another example, if the plurality of openings 46 are arranged in a manner that the plurality of openings 46 are arranged on the housing 41 in a circumferential direction of the cylindrical cavity 45 and in an axial direction of the cylindrical cavity 45, the housing 41 may rotate around the axis of the cylindrical cavity 45 or translate in the axial direction of the cylindrical cavity 45, so that the opening 46 to be opened in the plurality of openings 46 is moved to the position of the discharge hole 48, and is shielded by the shielding portion 47 to form the discharge hole 48.

The manner in which the discharge port 48 is formed will be described below.

The spindle 42 is rotatable about the axis of the cylindrical bore 45. The rotating shaft 42 can adopt a double-rotating shaft scheme as shown in fig. 5 or fig. 24, and two rotating shafts (421 and 422 as shown in fig. 5 or fig. 24) are respectively arranged at two ends of the opening 46. Alternatively, the pivot 42 may be a single pivot as shown in fig. 25 or 26, with the pivot being provided at only one end of the opening 46.

The rotary shaft 42 has a shielding portion 47 provided at the shaft end of the rotary shaft 42. As shown in fig. 5 or 25, the curtain portion 47 is located in the cylindrical cavity 45 and generally above the opening 46. The rotation of the rotary shaft 42 can change the area of the shielding portion 47 shielding the opening 46. As shown in fig. 5, 6, or 7, the discharge hole 48 may be formed in the area of the opening 46 that is not blocked by the blocking portion 47. Thus, rotation of the shaft 42 continuously changes the length of the discharge port 48.

The rotational axis of the shielding portion 47 can change the shielding relationship between the opening 46 and the shielding portion 47. The specific manner of changing the occlusion relationship can be various.

As an example, the shielding portion 47 and the cylindrical inner cavity 45 may be provided with a clearance fit, and the outer end face of the shielding portion 47 may be provided with a slope, and the shielding relationship between the shielding portion 47 and the opening 46 may be changed by a characteristic that the slope continuously changes.

As another example, the shielding portion 47 may be screwed with the cylindrical inner cavity 45, and the shielding relationship between the shielding portion 47 and the opening 46 may be changed by means of screw feeding. The manner of changing the shielding relationship between the shielding portion 47 and the opening 46 will be described in detail with reference to specific embodiments, and will not be described in detail here.

Spout 48 has a first end and a second end defining its length. When the swivel 42 employs a dual swivel arrangement as shown in fig. 5 and 24, a first swivel 421 can be used to adjust the position of the first end in the opening 46 and a second swivel 422 can be used to adjust the position of the second end in the opening 46. When the shaft 42 is a single-shaft solution as shown in fig. 25 and 26, the single-shaft 42 can be used to adjust the position of the first end in the opening 46, and the second end overlaps with one end of the opening 46 (i.e., the second end of the discharge hole 48 is the same end as one end of the opening 46).

The width of the spout 48 may affect the width of the molten material extruded by the spout 48, which in turn affects the accuracy of the 3D printing.

The width of spout 48 may be the same as the width of opening 46 moved to the spout position, i.e., the width of spout 48 is dependent on the width of opening 46. A plurality of openings 46 with different widths are provided on the housing 41, and the housing 41 can move relative to the rotating shaft 42 to move the openings 46 with different widths to the discharge hole position, so that the openings are shielded by the shielding part 47 to form the discharge hole 48. Because the opening 46 to the spout is switchable, the width of the spout 48 is made switchable. For example, the width of the plurality of openings 46 may range from 0.01mm to 5mm, and the width of the discharge hole 48 may be switched from 0.01mm to 5 mm.

In the device 4 for 3D printing provided by the present application, the housing 41 is provided with a plurality of openings 46 with different widths, and the housing 41 can move relative to the rotating shaft 42 so that the openings 46 with different widths are shielded by the shielding portion 47 to form the discharge port 48, so that the width of the discharge port 48 can be switched, and thus the printing precision can be adjusted in real time and rapidly according to the requirement of 3D printing precision, and the flexibility of 3D printing is improved.

Alternatively, spout 48 may be configured as a spout having an adjustable width. For example, a shutter (not shown) may be further provided at the opening 46. The shutter is slidable in the width direction of the opening 46 so as to shutter the opening 46 in the width direction to change the width of the discharge port 48. The shielding plate may be located on a side wall of the opening 46, or may be located at an outer end of the opening 46, which is not limited in the embodiment of the present application. The discharge port 48 is set to be a discharge port with adjustable width, so that the printing precision can be better adjusted according to actual needs.

Optionally, in some embodiments, the apparatus 4 may further comprise a feed inlet 43, as shown in fig. 5, 6, 24, 25, 26, or 29. The feed port 43 may communicate with a feed passage 49 (the feed passage 49 is shown in fig. 5 or 25) surrounded by an outer end surface of the shielding portion 47 and an inner surface of the housing 41. During actual printing, materials can enter the material conveying channel from the feeding hole and are extruded out from the discharging hole with continuously adjustable length. The location and arrangement of the feed opening 43 can be varied. For example, the feed opening 43 may be provided on the housing 41, as shown in fig. 5, 6, 24, 25, or 26; the feed port 43 may also be disposed on the rotary shaft 42, as shown in fig. 29, which will be described in detail later in connection with specific embodiments, and will not be described in detail here.

Optionally, in some embodiments, as shown in fig. 4 and 25, the apparatus 4 may further comprise a driving device 44.

The drive device 44 is used to drive the housing 41 to move relative to the spindle 42.

For example, the driving device 41 may be connected to the housing 41 for driving the housing 41 to move relative to the rotating shaft 42. In the case where the plurality of openings 46 are arranged along the axial direction of the cylindrical inner cavity 45, the driving device 44 is used for driving the housing 41 to translate along the axial direction of the cylindrical inner cavity 45 relative to the rotating shaft 42. The driving device 44 is for driving the housing 41 to rotate about the axis of the cylindrical cavity 45 with respect to the spindle 42, with the plurality of openings 46 arranged in the circumferential direction of the cylindrical cavity 45.

Alternatively, the driving device 44 may be connected to the rotating shaft 42, and the movement of the driving housing 41 relative to the rotating shaft 42 may be equivalently realized by driving the rotating shaft 42 to move.

The driving device 44 is also used for driving the rotary shaft 42 to rotate around the axis of the cylindrical inner cavity 45 so as to continuously change the area of the shielding part 47 shielding the opening 46 and further continuously change the length of the discharge hole 48.

For example, a drive device 44 may be coupled to the spindle 42 for driving the spindle 42 to rotate about the axis of the cylindrical bore 45.

The specific implementation of the driving device 44 can be various, and the embodiment of the present application is not limited thereto, for example, the driving device 44 can include a servo motor, and for example, the driving device 44 can be a rack and pinion mechanism, and can also be a crank slider mechanism.

As an example, in the driving device 44, a member for driving the housing 41 to move relative to the rotating shaft 42 may be referred to as a first driving unit, and a member for driving the rotating shaft 42 to rotate about the axis of the cylindrical inner cavity 45 may be referred to as a second driving unit. The first drive unit and the second drive unit may be drive components that the drive device 44 enables upon receiving two different control commands. For example, when receiving the first control instruction, the driving device 44 enables the first driving unit to drive the housing 41 to move relative to the rotating shaft 42, so that the opening 46 to be opened in the plurality of openings 46 is shielded by the shielding portion 47 to form the discharge hole 48; the driving device 44 enables the second driving unit to drive the rotating shaft 42 to rotate around the axis of the cylindrical inner cavity 45 under the second control instruction, so as to continuously change the area of the shielding part 47 shielding the opening 46, and thus continuously change the length of the discharge hole 48.

It is noted that the discharge port 48 provided in the embodiments of the present application may be a discharge port with a continuously adjustable length. Compare with the design of traditional 3D printer head's discharge gate, design into length continuously adjustable's discharge gate 48, overcome the constraint of traditional discharge gate design theory, this kind of neotype discharge gate has obvious advantage and wide application prospect. This is analyzed as follows.

The discharge gate of traditional 3D printing apparatus follows the design theory of 2D printing apparatus's discharge gate, designs the fixed nozzle of shape with the discharge gate. The discharge hole 48 is designed to be a discharge hole with a length continuously adjustable within a certain range in the embodiment of the application. The device is designed on the basis of fully considering the characteristics of a 3D printing object, compared with the traditional 3D printing device, the device provided by the embodiment of the application enables the balance between the efficiency and the precision of 3D printing to be possible, and is more suitable for 3D printing. The specific discussion is as follows.

The size of the 2D printing object is generally small, and the printing object is mainly text or images. The characters or images can be freely arranged on a two-dimensional plane without regularity. Therefore, the discharge port of the 2D printing device is designed to be a nozzle with a fixed shape, so that the design is reasonable in the field of 2D printing. Unlike the 2D printed object, the 3D printed object is generally a 3D article that needs to be actually used. A 3D object has a certain physical profile, and therefore, a sectional line of the 3D object along a certain section is usually one or more closed and continuously varying curves. The embodiment of the application makes full use of the characteristic of a 3D printing object, the opening 46 is arranged on the shell 41, and the blocking portion 47 of the rotating shaft 42 is used for blocking the opening 46, so that the length of the discharge port 48 is continuously adjustable. The continuous adjustable length of the discharge port 48 is matched with the characteristic that the section contour line of the 3D printing object is closed and continuously changed, and the discharge port 48 is more suitable for 3D printing, so that the printing efficiency can be greatly improved.

For example, with the discharging hole provided in the embodiment of the present application, continuous printing can be performed along the cross-sectional contour line, and the discharging hole 48 is controlled to change along with the change of the cross-sectional contour line during the printing process, which can be understood as having ultrahigh printing efficiency compared with the conventional way of printing pass by pass.

Further, by the movement of the housing 41 relative to the rotating shaft 42, one of the plurality of openings 46 with a smaller width can be used as an opening for shielding the shielding portion 47, so that the printing precision of the 3D object can be kept unchanged, and can be kept at a higher precision, and the printing precision can be kept unchanged during the continuous change of the length of the discharge port 48, which is difficult to achieve by the conventional 3D printing head. Therefore, the discharge gate that length continuously adjustable that this application embodiment provided makes efficiency and the precision of taking into account 3D printing possible, is suitable for 3D more and prints.

Further, in the apparatus 4 provided in the embodiment of the present application, the housing 41 is provided with a plurality of openings 46 with different widths, and the housing 41 is movable relative to the rotating shaft 42, so that the openings 46 with different widths in the plurality of openings 41 are shielded by the shielding portion 47 to form the discharge hole 48 (or, the different openings 46 are moved to the position of the discharge hole 48, or, the openings with different widths are communicated with the discharge hole)). The width of opening 46 affects the width of spout 48, and the width of spout 48 affects the width of the extruded material, which in turn affects 3D printing accuracy. The plurality of openings 46 with different widths are designed so that the device 4 can select openings with different accuracies (corresponding to selecting outlets with different accuracies) for printing according to actual needs. Therefore, the opening for forming the discharge port can be switched in real time and rapidly according to the printing precision requirement of the 3D object, so that the real-time and rapid switching of the printing precision can be realized.

For example, assuming that the layer to be printed includes a first print region in which the cross-sectional outline changes sharply in the vertical direction and a second print region in which the cross-sectional outline changes gently in the vertical direction, when the first print region is printed using the apparatus 4, it is possible to switch to an opening having a smaller width to improve the printing accuracy; when the second printing area is printed by using the device 4, the opening with a large width can be switched to, so that the printing efficiency is improved on the premise of ensuring the printing precision.

Further, a rotating shaft type structure is adopted, and the rotating shaft 42 and the shell 41 are tightly sleeved together, so that the rotating shaft type device provided by the embodiment of the application has the advantage of compact structure. The rotation angle of the rotary shaft 42 and the length of the discharge port 48 have a corresponding relationship, and when it is desired to adjust the length of the discharge port 48 to a specific value in actual operation, the rotation angle of the rotary shaft 42 may be adjusted to a rotation angle corresponding to the specific value. Therefore, the rotary shaft type device provided by the embodiment of the application has the advantage of simple control.

As will be appreciated from the foregoing description, the length of spout 48 may be continuously adjusted by rotation of shaft 42, several possible adjustments to the length of spout 48 are provided below.

Alternatively, rotation of the spindle 42 may cause the length of the discharge port 48 to vary as the shape of the target print area varies. The target printing area may be a partial printing area of the layer to be printed, or may be an entire printing area of the layer to be printed.

For example, in some embodiments, rotation of the swivel 42 may cause the length of the outfeed 48 to match the length of the section line of the cross-sectional outline of the target print area of the layer to be printed. Since the length of the discharge port 48 matches the length of the section line of the cross-sectional contour line, a basis for completing printing of the target printing region at one time can be provided.

Further, in some embodiments, the two ends of the dispensing spout 48 (which refer to the two ends defining the length of the dispensing spout 48) may be aligned with the cross-sectional contour of the target print area in a vertical direction. If the two ends of the dispensing opening 48 are vertically aligned with the cross-sectional contour of the target printing area, the projections of the two ends of the dispensing opening 48 in the vertical direction will be on the section line of the cross-sectional contour of the target printing area. For convenience of description, this printing manner will be hereinafter referred to as tracing printing of the cross-sectional outline of the target printing region.

The following describes the tracing printing in more detail with reference to fig. 6 and 7, taking the double-rotation-axis scheme as an example.

Referring to fig. 6 and 7, reference numeral 50 denotes a deposited portion of an article to be printed, reference numeral 52 denotes a target printing area of a layer to be printed, and the lengthwise direction of the discharge port 48 extends in the x direction.

The housing 41 may be controlled to move in the y direction as a whole during printing of the target printing area 52. During the movement of the housing 41, the length and/or position of the discharging port 48 is changed in real time by the rotating shaft 42, so that both ends of the discharging port 48 are always aligned with the sectional contour line of the target printing area 52 in the vertical direction z, i.e. it is obtained that the projections of both ends of the discharging port 48 in the vertical direction z always fall on the sectional contour line of the target printing area 52.

For example, assuming that the y coordinate of the current position of the discharging hole 48 is y1, and y1 cuts the cross-sectional contour line of the target printing area 52 along the x direction to obtain two points (x1, y1) and (x2, y1), the positions of the two ends of the discharging hole 48 can be changed in such a way that the first end is located right above (x1, y1) and the second end is located right above (x2, y1), so that the cross-sectional contour line of the target printing area 52 can be accurately tracked and printed.

Fig. 7 provides a schematic representation of the printing process shown in fig. 6 in the x-y plane. As more clearly shown in fig. 7, the length of the discharge hole 48 and the position thereof in the x direction may be changed according to the change in the shape of the cross-sectional contour of the target print area 52, and the cross-sectional contour of the target print area 52 is kept accurately trace-printed.

The tracing printing of the cross-sectional contour of the target print area may be implemented in various ways.

Alternatively, as a first implementation, rotation of the rotating shaft 42 may be utilized to vertically align both ends of the discharge hole 48 with the cross-sectional contour of the target printing area.

Alternatively, as a second implementation manner, the rotating shaft 42 may be driven to rotate by the driving device 44, so that the length of the discharge port 48 matches the section line length of the section contour line of the target printing area of the layer to be printed; and drives the relative movement between the housing 41 and the printing table (not shown) by another driving means (not shown) so that both ends of the discharge port 48 are aligned with the sectional outline of the target printing area in the vertical direction.

In the process of printing the target printing area, the device 4 may implement tracking printing by using one of the two implementation manners according to actual needs; alternatively, different tracing print modes may be employed when printing different portions of the target print area.

For example, the target print area may include a portion having a shorter stub length and a portion having a longer stub length. When printing the part with the short stub length, the tracing printing can be performed in the first implementation manner; when printing the part where the stub length is long, the tracing printing can be performed in the second implementation.

Compared with the objects printed by the traditional discharge port, the cross-section contour line of the target printing area is subjected to tracking printing, and the mechanical property and the shape uniformity of the printed objects are also remarkably improved, which is discussed in detail below with reference to fig. 8 and 9.

The conventional 3D printing is generally performed channel by channel according to a certain pass sequence. Because the size of the discharge port of the conventional 3D printing apparatus is small (the caliber is usually in the millimeter level), it takes a long time to print each pass. When the current pass is ready to be printed, the material on the previous pass adjacent to the current pass may already be at or near a solidified state while the material on the current pass is still in a molten state. The material in the molten state on the current pass needs to be fused with the material in the previous pass which is already in or close to the solidification state to form a whole, and the process of material fusion between the adjacent passes is called pass overlapping.

In the process of pass overlapping, if the previous pass of the current pass is solidified or nearly solidified and the current pass is still in a molten state, the phenomenon of poor fusion can occur in the material fusion process between the adjacent passes, so that the mechanical property of the printed article is poor. In addition, because the material states are asynchronous, the shape of an object obtained after materials on adjacent passes are fused with each other is rough. Taking a printing cylinder as an example, as shown in fig. 8, the cylinder 61 is a cylinder printed by using a conventional 3D printing technique and using a pass overlapping manner. The cylindrical body 61 has a rough overall shape and profile, and has a plurality of notches 63 due to poor material fusion during the pass overlapping process.

The device 4 provided by the embodiment of the application performs tracing printing on the section contour line of the target printing area by adjusting the length and the position of the discharge hole 48. Therefore, in the process of printing the target printing area, the device 4 does not need to perform pass-by-pass printing according to the pass, and also does not need to perform pass overlapping, so that the problem of poor fusion cannot be caused. Therefore, the printed article by the device 4 has high mechanical properties. As shown in fig. 8, the cylinder 62 is a cylinder printed by the apparatus 4, and compared with the cylinder 61, the fusion of the filling material of the cylinder 62 is good, and the problem of poor fusion caused by pass overlapping does not exist.

Still taking the printing of a cylinder as an example, referring to fig. 9, in the conventional 3D printing process, the switching between passes uses a polygonal line 72 instead of the true contour curve, i.e., the polygonal line is used to approximate the true contour curve, resulting in a rough contour of the printed cylinder 62. The device 4 provided by the embodiment of the application does not need to print according to the pass, but tracks and prints the section contour line of the target printing area by adjusting the length and the position of the discharge hole 48, so that the contour line of the cylinder 62 printed by the device 4 is smoother and more real.

The target print area may be determined in various ways. For example, whether the printing is performed by dividing the printing area of the layer to be printed into the plurality of target printing areas, or by setting the entire printing area of the layer to be printed as the target printing area, may be determined according to one or more of the factors of the shape of the cross-sectional contour line of the layer to be printed, the length of the longest sectional line, and the size of the discharge opening.

For example, when the length of the longest sectional line of the cross-sectional outline of the layer to be printed is less than or equal to the maximum length of the discharge port 48 (the maximum length of the discharge port 48 may be less than or equal to the length of the opening 46), the entire printing area of the layer to be printed may be determined as the target printing area; when the length of the longest sectional line of the cross-sectional outline of the layer to be printed is greater than the maximum length of the discharge port 48, the entire printing area of the layer to be printed may be divided into a plurality of target printing areas.

For another example, when the cross-sectional contour line of the layer to be printed includes a plurality of closed regions that are not connected, each closed region may be printed as one or more target print regions.

For another example, in some embodiments, the entire printing area of the layer to be printed may be directly used as the target printing area without dividing the entire printing area of the layer to be printed. For example, the apparatus 4 may be designed as a dedicated apparatus dedicated to printing a specific article, and the length of the discharge port of the apparatus 4 may be designed to be able to print all the printing areas of each printing layer of the article at once. In this way, in operation, the device 4 can print each layer of the article in a fixed manner without the need for on-line division of the print zone.

As shown in fig. 4 or 25, the driving device 44 may operate under the control of the control device 40. The control device 40 may be a dedicated numerical control device or a general-purpose processor. The control device 40 may be a distributed control device or a centralized control device.

The control means 40 may control the length and/or position of the discharge orifice 48 by the drive means 44 in accordance with the shape of the cross-sectional profile of the target print zone (which may be part or all of the print zone of the layer to be printed).

The control device 40 can also control the movement of the housing 41 relative to the rotating shaft 42 through the driving device 44 according to the printing precision requirement, so that an opening 46 (i.e. an opening 46 required to be opened) meeting the printing precision requirement in the plurality of openings 46 arranged on the housing 41 is moved to the position of the discharge port, so as to be shielded by the shielding portion 47 to form the discharge port 48 with continuously variable length.

Based on the above description, the discharge gate with the continuously adjustable length provided by the embodiment of the application makes it possible to take into account the efficiency and the precision of 3D printing, and is more suitable for 3D printing.

In addition, the opening of a plurality of different width that this application embodiment provided for can be according to printing the precision demand, real-time, switch over fast and print the precision, can compromise efficiency and precision that 3D printed better.

Alternatively, as shown in fig. 10, in the embodiment in which the plurality of openings 46 are arranged along the axial direction of the cylindrical cavity, the apparatus 4 may further comprise a seal 413 for axially fixing the rotating shaft 42. The axial fixation of the rotary shaft 42 means that the relative displacement between the rotary shaft 42 and the housing 41 in the axial direction is blocked.

For example, in the embodiment shown in fig. 4, 10, 14, 15 or 16, the rotary shaft 42 is axially fixed by the seal 413 after the opening 46 to be opened of the plurality of openings 46 is moved to the position of the discharge port 48 by the axial translation of the housing 41 along the cylindrical inner cavity 45. In this way, in the process of continuously changing the length of the discharge port 48 by the rotation of the rotary shaft 42, the axial relative movement between the housing 41 and the rotary shaft 42 can be avoided, so that the printing precision can be effectively ensured to be kept unchanged in the process of continuously changing the length of the discharge port 48.

As an example, the end cap 413 may be installed to axially fix the rotating shaft 42 after the opening 46 to be opened of the plurality of openings 46 is moved to the position of the discharge hole 48 by the axial translation of the housing 41 along the cylindrical inner cavity 45.

As another example, the end cap 413 may be mounted on the apparatus 4 at all times, and when the axial fixation of the rotating shaft 42 is required, a connecting assembly (e.g., a nut and bolt assembly) for fastening the end cap 413 and the housing 41 is tightened to axially fix the rotating shaft 42.

Alternatively, as shown in fig. 13 or fig. 20, in an embodiment in which the plurality of openings 46 are arranged in the circumferential direction of the cylindrical inner cavity 45, the apparatus 4 may further include an enclosure 414 for closing off the openings 46 that do not need to be opened among the plurality of openings 46 provided on the housing 41.

For example, in the embodiment shown in fig. 11, 12 or 19, after the opening 46, which needs to be opened, of the plurality of openings 46 is moved to the position of the discharge port 48 by rotating the housing 41 along the axis of the cylindrical inner cavity 45, the capsule 414 is installed to close off the opening 46, which does not need to be opened, of the plurality of openings 46 provided on the housing 41, and the schematic diagram after the capsule 414 is installed is shown in fig. 13.

As an example, assuming that the position where the discharge port 48 is located is regarded as the front surface of the rotary shaft 42, the housing 41 is rotated around the axis of the cylindrical cavity 45 so that the opening 46 that needs to be opened is moved to the front surface of the rotary shaft 42, and at the same time, the opening 46 that does not need to be opened is moved to the side surface or the back surface of the rotary shaft 42. In this example, the enclosure 414 is mounted outside the housing 41 so as to cover the openings 46 moved to the side or back of the rotary shaft 42, thereby closing these openings 46.

The enclosure 414 may be the housing of the device 4. For example, the enclosure 414 is the housing of the printhead.

Sealing the openings 46 that do not need to be opened with the capsule 414 prevents material from escaping through the openings 46 that do not need to be opened.

In some embodiments, the size of the opening 46 may be fixed. For example, the size of each opening 46 provided in the housing 41 is fixed. The dimensions of the opening 46 include length and width.

In other embodiments, the size of the opening 46 is adjustable, i.e., the opening 46 is an adjustable-size opening.

For example, the opening 46 is a continuously adjustable length opening.

Alternatively, the size of the opening 46 is adjusted such that the length of the opening 46 is the same as the length of the area of the opening 46 that is not blocked by the blocking portion 47.

The housing 41 has a thickness that is a distance from the inner cavity surface to the outer wall of the housing 41, i.e., the material will pass through a section of the extrusion channel in the opening 46 before exiting the outlet 48. If the length of opening 46 is greater than the length of the area of opening 46 not covered by shield 47, it may cause material to spread within the extrusion path of opening 46 before exiting outlet 48. Ideally, the length of the outlet 48 should be consistent with the length of the area of the opening 46 not covered by the covering portion 47, but if the material extends in the extrusion channel of the opening 46 before exiting the outlet 48, the length of the outlet 48 may not be consistent with the length of the area of the opening 46 not covered by the covering portion 47, which may affect the accuracy of controlling the length of the outlet 48.

In an embodiment, the opening 46 is a size-adjustable opening, and the size of the opening 46 is adjusted such that the length of the opening 46 is the same as the length of the area of the opening 46 not shielded by the shielding portion 47, which can prevent the material from extending in the extrusion channel of the opening 46 before the material is separated from the discharge hole 48, so that the accuracy of controlling the length of the discharge hole 48 can be improved, and the printing efficiency and the printing accuracy can be better considered.

The manner in which the opening 46 is implemented as a length-adjustable opening may vary.

For example, the housing 41 may include separable portions. The abutting surfaces of the plurality of portions may define a plurality of openings 46 and the plurality of portions may be movable relative to one another (e.g., axially along the cylindrical bore 45) to adjust the size of the plurality of openings 46.

For example, the plurality of portions are relatively slidable in the axial direction of the cylindrical inner cavity 45, thereby adjusting the length of the plurality of openings 46.

As shown in fig. 14, 15, 17, 18, or 19, the housing 41 includes a first portion 411 and a second portion 412. The first portion 411 and the second portion 412 are relatively slidable in the axial direction of the cylindrical cavity 45, so that a plurality of openings 46 with adjustable length (or continuously adjustable) can be formed.

The shape of the first and

second portions

411, 412 and the manner in which they form the plurality of openings 46 can be varied.

As an example, as shown in fig. 14 and 15, the first portion 411 and the second portion 412 have a first mating surface and a second mating surface therebetween. The first butt joint surface is a step-shaped butt joint surface, and the second butt joint surface is a plane-shaped butt joint surface.

The first abutting surface on the first portion 411 includes a first upper step surface 4111, a first lower step surface 4112, a second upper step surface 4113, a first connecting surface 4114 connecting the first upper step surface 4111 and the first lower step surface 4112, and a second connecting surface 4115 connecting the first lower step surface 4112 and the second upper step surface 4113, and a height difference between the first upper step surface 4111 and the first lower step surface 4112 is different from a height difference between the first lower step surface 4112 and the second upper step surface 4113. The first abutment surface on the second portion 412 includes a second lower step surface 4121, a third upper step surface 4122, a third lower step surface 4123, a third connection surface 4124 connecting the second lower step surface 4121 and the third upper step surface 4122, and a fourth connection surface 4125 connecting the third upper step surface 4122 and the third lower step surface 4123. First upper step surface 4111, first lower step surface 4112, and second upper step surface 4113 are in contact with second lower step surface 4121, third upper step surface 4122, and third lower step surface 4123, respectively, and are relatively slidable in the axial direction. The hollow areas formed by the first upper step surface 4111, the first connecting surface 4114, the third upper step surface 4122 and the third connecting surface 4124 are one opening (denoted as opening 46(1)), and the hollow areas formed by the second upper step surface 4113, the fourth connecting surface 4125, the third upper step surface 4122 and the second connecting surface 4115 are the other opening (denoted as opening 46 (2)). Since the difference in height between first upper step surface 4111 and first lower step surface 4112 is different from the difference in height between first lower step surface 4112 and second upper step surface 4113, opening 46(1) is different in width from opening 46 (2).

The first portion 411 and the second portion 412 are relatively slidable in the axial direction of the cylindrical cavity 45 to adjust the lengths of the opening 46(1) and the opening 46 (2).

For example, in the example of fig. 14 or 15, the relative sliding of the first portion 411 and the second portion 412 in the axial direction of the cylindrical cavity 45, with a tendency to progressively move them away from each other, may increase the length of the opening 46(1), while at the same time decreasing the length of the opening 46 (2); the first portion 411 and the second portion 412 slide relatively in the axial direction of the cylindrical cavity 45 in a tendency to gradually approach each other, so that the length of the opening 46(2) can be increased, and at the same time, the length of the opening 46(1) can be decreased.

In the example of fig. 14 or 15, the openings 46(1) and 46(2) formed by splicing the first portion 411 and the second portion 412 are arranged along the axial direction of the cylindrical inner cavity 45, and then the housing 41 (i.e., the whole of the first portion 411 and the second portion 412) can be translated along the axial direction of the cylindrical inner cavity 45, so that different openings 46 in the plurality of openings 46 are shielded by the shielding part 47 to form the discharge port.

As an example, in the example of fig. 14 or fig. 15, in the case of the opening 46(1) as the opening to be opened, after the opening 46(1) is moved to the discharge port position by the axial translation of the housing 41 along the cylindrical inner cavity 45, the first portion 411 and the second portion 412 relatively slide along the axial direction of the cylindrical inner cavity 45, and the length of the opening 46(1) is adjusted so that the length of the opening 46(1) is the same as the length of the area of the opening 46(1) which is not covered by the covering portion 47.

Referring to fig. 10, in the embodiment shown in fig. 14 or 15, the apparatus 4 may also include a seal 413 (not shown in fig. 14 or 15) for axially securing the swivel 42. The axial fixation of the rotary shaft 42 means that the relative displacement between the rotary shaft 42 and the housing 41 in the axial direction is blocked.

After the opening 46 to be opened in the plurality of openings 46 is moved to the position of the discharge port 48 by the axial translation of the housing 41 along the cylindrical inner cavity 45, the rotary shaft 42 is axially fixed by the seal 413. In this way, in the process of continuously changing the length of the discharge port 48 by the rotation of the rotary shaft 42, the axial relative movement between the housing 41 and the rotary shaft 42 can be avoided, so that the printing precision can be effectively ensured to be kept unchanged in the process of continuously changing the length of the discharge port 48.

It should be noted that fig. 14 and 15 are only examples and are not limited. For example, the first mating surface between the first portion 411 and the second portion 412 may have more step surfaces, so that various numbers of openings 46 may be designed according to actual needs (for example, an odd number of openings 46 may be designed, and an even number of openings 46 may also be designed).

As another example, as shown in fig. 17, 18 and 19, the first portion 411 and the second portion 412 have a first mating surface and a second mating surface therebetween. The first and second mating surfaces each include a step surface.

The first abutting surface on the first portion 411 includes a first upper step surface 4111a, a first lower step surface 4112a, and a first connecting surface 4113a connecting the first upper step surface 4111a and the first lower step surface 4112 a. The first abutting surface of the second portion 412 includes a second upper stepped surface 4121a, a second lower stepped surface 4122a, and a second connecting surface 4123a connecting the second upper stepped surface 4121a and the second lower stepped surface 4122 a. The second abutting surface on the first portion 411 includes a third upper step surface 4111b, a third lower step surface 4112b, and a third connecting surface 4113b connecting the third upper step surface 4111b and the third lower step surface 4112 b. The second abutment surface on the second portion 412 includes a fourth upper step surface 4121b, a fourth lower step surface 4122b, and a fourth connection surface 4123b connecting the fourth upper step surface 4121b and the fourth lower step surface 4122 b. The first upper step surface 4111a and the first lower step surface 4112a are respectively in contact with the second lower step surface 4122a and the second upper step surface 4121a, and can relatively slide in the axial direction, and the hollow area formed by the first lower step surface 4112a, the first connecting surface 4113a, the second lower step surface 4122a and the second connecting surface 4123a is an opening (denoted as an opening 46(1)) (the opening 46(1) is shown in fig. 17 and 19). Third upper step surface 4111b and third lower step surface 4112b are in contact with fourth lower step surface 4122b and fourth upper step surface 4121b, respectively, and are relatively slidable in the axial direction, and a hollow area formed by third lower step surface 4112b, third connection surface 4113b, fourth lower step surface 4122b and fourth connection surface 4123b is another opening (denoted as opening 46(2)) (opening 46(2)) is shown in fig. 19.

A height difference between the first upper step surface 4111a and the first lower step surface 4112a is different from a height difference between the third upper step surface 4111b and the third lower step surface 4112b (corresponding to a height difference between the second upper step surface 4121a and the second lower step surface 4122a being different from a height difference between the fourth upper step surface 4121b and the fourth lower step surface 4122 b). Therefore, the width of the opening 46(1) is different from that of the opening 46 (2).

In this example, the first part 411 and the second part 412 are butted together in a staggered and complementary stepped structure, and the relative sliding of the two parts along the axial direction of the cylindrical inner cavity 45 can form a plurality of openings 46 with continuously adjustable lengths: opening 46(1) and opening 46 (2).

For example, in the present example, the first portion 411 and the second portion 412 slide relatively in the axial direction of the cylindrical cavity 45 with a tendency to move away from each other, and the lengths of the opening 46(1) and the opening 46(2) may be increased; the first portion 411 and the second portion 412 slide relatively in the axial direction of the cylindrical cavity 45 in a tendency to gradually approach each other, and the lengths of the opening 46(1) and the opening 46(2) can be reduced.

In this example, the openings 46(1) and 46(2) formed by splicing the first portion 411 and the second portion 412 are arranged along the circumferential direction of the cylindrical inner cavity 45, and the housing 41 (i.e. the whole of the first portion 411 and the second portion 412) can rotate along the axis of the cylindrical inner cavity 45, so that different openings 46 in the plurality of openings 46 are shielded by the shielding portion 47 to form the discharge port.

In this example, in the case of the opening 46(1) as the opening to be opened, after the opening 46(1) is moved to the discharge port position by rotating the housing 41 along the axis of the cylindrical cavity 45, the first portion 411 and the second portion 412 relatively slide in the axial direction of the cylindrical cavity 45, and the length of the opening 46(1) is adjusted so that the length of the opening 46(1) is the same as the length of the area of the opening 46(1) which is not blocked by the blocking portion 47.

Referring to fig. 13, in the embodiment shown in fig. 17, 18 or 19, the apparatus 4 may also include an enclosure 414 for closing off openings 46 of the plurality of openings 46 provided in the housing 41 that need not be open.

As an example, as shown in fig. 20, taking the opening 46(1) as an opening to be opened as an example, the enclosure 414 is used to close off the remaining openings 46 except the opening 46(1) in the plurality of openings 46 provided in the housing 41.

It should be noted that fig. 17, 18, or 19 are only examples and are not limited. For example, the housing 41 may further include a first portion, a second portion, a third portion and a fourth portion, wherein two abutting surfaces of any two abutting portions include a step surface, the four portions may form 4 openings 46 arranged along the circumferential direction, and the four portions relatively slide along the axial direction of the cylindrical inner cavity 45, and the length of the 4 openings 46 may be adjusted. Thus, various numbers of openings 46 can be designed according to actual needs (for example, an odd number of openings 46 can be designed, and an even number of openings 46 can also be designed).

As yet another example, the first portion 411 and the second portion 412 may have a concavo-convex complementary structure. The relative sliding of the first and

second portions

411, 412 along the axial direction of the cylindrical cavity 45 may modify the relative positional relationship between the concave and convex portions, i.e., the hollow areas between the concave and convex portions may form a plurality of openings 46 with continuously adjustable lengths.

As still another example, the first portion 411 and the second portion 412 have a first abutting surface and a second abutting surface therebetween, wherein the first abutting surface and the second abutting surface each include a step surface, and the first abutting surface and/or the second abutting surface have a structure similar to the first abutting surface in the embodiment shown in fig. 14, and the first portion 411 and the second portion 412 are relatively slidable along the axial direction of the cylindrical inner cavity 45 to adjust the length of the opening 46.

In this example, the first portion 411 and the second portion 412 may form a plurality of openings 46 having different widths, and some of the openings 46 of the plurality of openings 46 are arranged in the circumferential direction of the cylindrical inner cavity 45, and some of the openings 46 are arranged in the axial direction of the cylindrical inner cavity 45. In the present example, the housing 41 is rotatable about the axis of the cylindrical inner cavity 45 and also translatable in the axial direction of the cylindrical inner cavity 45, so that different openings 46 of the plurality of openings 46 are shielded by the shielding portion 47 to form the discharge port.

For example, the housing 41 may further include a first portion, a second portion, a third portion and a fourth portion, wherein the abutting surface of two adjacent portions may be designed to be a plane surface, so that the two adjacent portions do not form an opening, and the abutting surface of two adjacent portions is designed to be a step surface, so that the two adjacent portions form an opening, so that various numbers of openings can be designed according to actual needs (for example, an odd number of openings may be designed, and an even number of openings may be designed).

The first part 411 and the second part 412 are indicated to slide relatively in the axial direction of the cylindrical cavity 45. It should be noted that the first portion 411 and the second portion 412 are not required to be slidable in the embodiments of the present application.

In one implementation, the first portion 411 and the second portion 412 are not fixed, and both can slide relative to the rotating shaft 42 along the axial direction of the cylindrical inner cavity 45.

As another way of realization, the first portion 411 can slide along the axial direction of the cylindrical inner cavity 45 relative to the rotating shaft 42, and the second portion 412 is fixedly connected with the rotating shaft 42 or is integrally formed with the rotating shaft 42. This implementation can simplify the control of the device 4.

In some embodiments, the end of the first portion 411 may be designed as a closed ring that fits over the swivel 42; and/or, the ends of the second portion 412 (the ends of the first portion 411 and the ends of the second portion 412 may define the axial length of the housing 41) may be configured as a closed circular ring that fits over the swivel shaft 42. This may enhance the overall rigidity and sealing of the housing 42.

In some embodiments, when the first portion 411 is a sliding member and the second portion 412 is a fixed member, both ends of the first portion 411 may be designed as a closed circular ring. This can enhance the overall rigidity and sealing property of the housing 41.

The foregoing describes an implementation that enables the length of the opening 46 to be continuously adjustable.

Also for example, the width of the opening 46 may be continuously adjustable.

Adjustment of the size of the opening 46 may be achieved by a drive means.

The drive means 44 also serve to adjust the size of the opening 46 such that the length of the opening 46 is the same as the length of the area of the opening 46 not obscured by the obscuration 47.

For example, in the embodiment shown in fig. 14, 15, 17, 18 or 19, the driving device 44 is further configured to drive the first portion 411 and the second portion 412 to be relatively slidable along the axial direction of the cylindrical inner cavity 45 to adjust the length of the opening 46, for example, so that the length of the opening 46 is the same as the length of the area of the opening 46 which is not blocked by the blocking portion 47.

Taking fig. 15 as an example, a bracket 91 for fixing the first part 411 and a bracket 92 for fixing the second part 412 may be provided in the housing 41, as shown in fig. 16. The driving device 44 can provide the bracket 91 and the bracket 92 with power for moving along the axial direction of the cylindrical inner cavity 45, so that the bracket 91 drives the first part 411 to move along the axial direction, and the bracket 92 drives the second part 412 to move along the axial direction.

For example, in the driving device 44, a member for adjusting the length of the opening 46 (e.g., driving the first portion 411 and the second portion 412 to be relatively slidable in the axial direction of the cylindrical inner cavity 45) may be referred to as a third driving unit. For example, in the case where the driving device 44 receives a third control command, the third driving unit is enabled for driving the first part 411 and the second part 412 to be relatively slidable in the axial direction of the cylindrical inner cavity 45, so that the length of the opening 46 is the same as the length of the area of the opening 46 which is not blocked by the blocking portion 47.

In the apparatus 4 provided in the embodiment of the present application, the opening 46 is a size-adjustable opening, and the size of the opening 46 is adjusted such that the length of the opening 46 is the same as the length of an area of the opening 46 that is not blocked by the blocking portion 47, which can prevent the material from extending in the extrusion channel of the opening 46 before the material is separated from the discharge hole 48, so as to improve the accuracy of controlling the length of the discharge hole 48, and further better achieve the compatibility between the printing efficiency and the printing accuracy.

In the above embodiments, the device 4 may further include a bracket disposed outside the housing 41 to fix the device 4.

For example, in the example of fig. 15, brackets are designed for the first part 411 and the second part 412, respectively, as shown in fig. 16.

The embodiment of the application also provides equipment for 3D printing, and the equipment has a discharge gate with adjustable length, and the extrusion channel of the discharge gate is a structure with a variable cross section along the material flow direction.

For example, the extrusion channel of the discharge port is a structure with a section gradually shrinking to the size required by the discharge port along the material flow direction. The size of the discharge port comprises width and length.

For example, the extrusion channel of the discharge port is a structure with a section gradually shrinking to the width required by the discharge port along the material flow direction. In other words, the width of the extrusion channel of the discharge port in the cross section along the material flow direction gradually shrinks to the width required by the discharge port.

For another example, the extrusion channel of the discharge port is a structure with a section gradually shrinking to a length required by the discharge port along the material flowing direction.

In order to realize that the extrusion channel of the discharge port is a structure with the section gradually contracted to the required size of the discharge port along the material flowing direction, the discharge port can be designed in various ways.

As one example, as shown in (b) of fig. 21, the cross section of the extrusion passage of the discharge port in the length direction is a stepped flow passage cross section.

As another example, as shown in (c) of fig. 21, the cross section of the extrusion channel of the discharge port in the length direction is a streamlined flow passage cross section.

Alternatively, the cross section of the extrusion channel of the discharge port in the length direction may also be designed into other feasible shapes or patterns as long as the extrusion channel of the discharge port is in a structure that the cross section gradually shrinks to the size required by the discharge port along the material flow direction.

As still another example, the cross section of the extrusion channel of the discharge port in the width direction may also be a stepped flow channel cross section or a streamlined flow channel cross section (not shown in the drawings).

The 3D printing extrusion material is generally a high-viscosity substance, the resistance generated by the extrusion material is proportional to the channel length of the discharge port, and when the width of the discharge port is small (when the printing precision is high, the width of the discharge port is required to be small), the discharge port is equivalent to a slit channel, as shown in (a) of fig. 21, the resistance of the extrusion material is very large, which may reduce the printing efficiency. In such a case, extruding the material out of the slit passage at a high speed to efficiently achieve high-precision 3D printing requires a very large extrusion pressure, which requires a very large conveying power of the material conveying system, and thus, the printing cost would be significantly increased, making the printing process uneconomical.

In the equipment that this application embodiment provided, the passageway of extruding of discharge gate is for following the structure that material flow direction cross-section shrinks gradually to the required size of this discharge gate, and this can effectively reduce the resistance that the material was extruded to be favorable to improving the efficiency that prints the shaping. In addition, because the resistance to material extrusion can be reduced, the requirement for the conveying power of the material conveying system can be reduced, and the printing cost can be reduced.

The application scenario of the present embodiment includes, but is not limited to, the device 4 provided in the above embodiment.

The following will explain the application of the present embodiment to the apparatus 4 provided in the above embodiment.

In the device 4 provided in the above embodiment, the housing 41 may have a certain thickness, and therefore, the opening 46 also has a certain thickness, or the opening 46 has a passage along the material flowing-out direction.

As described above, the area of the opening 46 that is not blocked by the blocking portion forms the discharge port 48, and the passage of the opening 46 is an extrusion passage of the material. That is, the passage of the opening 46 serves as an extrusion passage of the discharge port 48. The path of the opening 46 represents the path enclosed by the opening 46 through which the material flows.

In some embodiments, the passage of the opening 46 may be a structure having an equal cross section in the material flow direction, as shown in fig. 21 (a).

In other embodiments, the passage of the opening 46 may be of a variable cross-section configuration in the direction of material flow.

For example, the passage of the opening 46 is a structure that gradually narrows in cross-section in the material flow direction to a size required for the opening 46. The dimensions of the opening 46 include length and width.

For example, the passage of the opening 46 is a structure in which the cross section gradually narrows to a desired width of the opening 46 in the material flow direction. In other words, the width of the passage of the opening 46 in cross section in the material flow direction gradually narrows to a width required for the opening 46.

For example, the passage of the opening 46 is a structure in which the cross section gradually narrows to a desired length of the opening 46 in the material flow direction.

As an example, the cross section of the passage of the opening 46 in the length direction is a stepped flow passage cross section as shown in (b) in fig. 21.

As another example, the passage of the opening 46 has a cross section in the length direction of a streamlined flow passage section as shown in (c) of fig. 21.

Alternatively, the cross section of the channel of the opening 46 in the length direction can be designed into other feasible shapes or patterns, as long as the channel of the opening 46 is in a structure with the cross section gradually shrinking to the required size of the opening 46 along the material flow direction.

As still another example, the passage of the opening 46 has a cross section in the width direction of a stepped flow passage section or a streamlined flow passage section (not shown in the drawings).

In the case where the housing 41 is integrally formed, for example, in the case shown in fig. 4, 10, 11, 12 or 13, the opening 46 of which the passage is a structure that gradually shrinks in cross section to a size required for the opening 46 in the material flow direction may be formed by a housing mold.

In the case where the housing 41 includes a plurality of separable parts, for example, as in the case shown in fig. 14, 15, 17, 18, or 19, the opening 46 of the passage in a structure in which the cross section gradually shrinks to a size required for the opening 46 in the material flow direction may be formed by providing a stepped structure on the abutting surface of the adjacent two parts.

For example, in the above embodiments as shown in fig. 14, 15, 17, 18 or 19, the interface between the first portion 411 and the second portion 412 may have a stepped structure in the material outflow direction, so that the passage of the opening 46 is a structure that gradually narrows in cross section to a desired size of the opening 46 in the material outflow direction.

Taking the embodiment shown in fig. 18, 18 or 19 as an example, the abutting surface 4112a of the first portion 411 has a stepped structure along the material outflow direction, as shown in fig. 22, the abutting surface 4112a includes an upper stepped surface 41121a and a lower stepped surface 41122 a; the abutting surface 4122a of the second part 412 has a stepped structure along the material outflow direction, and as shown in fig. 22, the abutting surface 4122a includes an upper stepped surface 41221a and a lower stepped surface 41222 a. Thus, the passage of the opening 46(1) formed by the abutting of the first part 411 and the second part 412 is a structure with a gradually reduced cross section along the material flow direction to the required width of the opening 46, as shown in fig. 23. In this example, the passage of the opening 46(1) has a polygonal cross section in the longitudinal direction as shown in fig. 21 (b).

As described above, the 3D printing extrusion material is generally a high viscosity material, and the length of the extrusion channel of the discharge port 48 causes a great resistance to the extrusion of the material, which reduces the printing efficiency and increases the printing cost, making the printing process uneconomical.

In apparatus 4, the length of the channel of opening 46 determines the length of the extrusion channel of spout 48, and the channel of opening 46 typically has a certain length. Thus, the length of the passageway of the opening 46 provides a significant resistance to material extrusion, especially when the width of the opening 46 is small.

In an embodiment, the channel of the opening 46 is a structure whose cross section gradually shrinks to the width required by the opening 46 along the material flowing direction, so that the channel of the discharging port is a structure whose cross section gradually shrinks to the width required by the discharging port along the material flowing direction, which can effectively reduce the resistance of material extrusion, thereby being beneficial to improving the efficiency of printing and forming. In addition, because the resistance to material extrusion can be reduced, the requirement for the conveying power of the material conveying system can be reduced, and the printing cost can be reduced.

The manner of changing the shielding relationship between the shielding portion 47 and the opening 46 is described in detail below.

As an example, the fitting relationship of the shielding portion 47 (or the sidewall of the shielding portion 47) and the cylindrical inner cavity 45 may be set as a clearance fit, and the outer end face 471 of the shielding portion 47 is set as a slope (the slope may be implemented as shown in fig. 27). Since the outer end face 471 of the shielding portion 47 is set to be a slope, the axial length of the side wall of the shielding portion 47 along the rotating shaft 42 is not equal (or continuously varies).

The shape and structure of the shielding portion 47 can be arranged in a manner that the shielding portion 47 can rotate freely in situ, and the shielding portion 47 can still change the size of the area of the shielding opening 46 during the in situ rotation process. The advantage of this implementation is that the total volume of the delivery channel 49 remains constant, which is more conducive to controlling the amount of material extruded from the outlet 48.

The gap between the shield 47 and the cylindrical interior 45 should be set as small as possible, so that no or little printing material is squeezed into this gap.

With the rotation of the rotary shaft 42, different portions of the shielding portion 47 are located above the opening 46. Since the length of the shielding portion 47 in the axial direction is different at different portions, when the shielding portion 47 is shielded above the opening 46, the shielded area in the opening 46 is changed, so that the area shielded by the shielding portion 47 in the opening 46 can be changed.

For convenience of description, a portion where the shielding portion 47 is shortest in the axial direction (e.g., a portion corresponding to a position a in fig. 27) may be referred to as a lowest shielding portion of the shielding portion 47, and a portion where the shielding portion 47 is longest in the axial direction (e.g., a portion corresponding to a position b in fig. 27) may be referred to as a highest shielding portion of the shielding portion 47. Assuming that the rotating shaft 42 adopts a double-rotating-shaft scheme as shown in fig. 5, the outer end face 471 of the shielding portion 47 can be designed such that when the lowest shielding portion of the shielding portion 47 rotates to above the opening 46, the opening 46 is not shielded and is in a fully opened state; when the highest shielding portion of the shielding portion 47 is rotated to above the opening 46, half of the opening 46 is shielded. Thus, when the highest shielding portions of the shielding portions 47 of the

rotating shafts

421 and 422 are rotated to be above the opening 46, the opening 46 is substantially completely shielded, so that the length of the discharge hole 48 can be continuously changed from 0 to the length of the opening 46.

For another example, if the rotating shaft 42 adopts a single-rotating-shaft scheme as shown in fig. 25, the outer end face 471 of the shielding portion 47 can be designed such that when the lowest shielding portion of the shielding portion 47 rotates to above the opening 46, the opening 46 is not shielded and is in a fully opened state; when the highest shielding portion of the shielding portion 47 is rotated to above the opening 46, the opening 46 is substantially completely shielded, so that the length of the discharge hole 48 can be continuously changed between 0 and the length of the opening 46.

The spiral slope shown in fig. 27 is only one possible implementation of the slope, and the embodiment of the present application is not limited thereto, and the outer end face 471 of the shielding portion 47 may also be another type of slope, such as a slope plane or a slope curved surface with some curvature.

In order to ensure that the outlet 48 is tightly closed, see fig. 28, a flat surface 472 perpendicular to the axis of the cylindrical bore 45 may be provided at the top of the slope 471.

When the rotary shaft 42 adopts the double-rotary-shaft scheme as shown in fig. 5, because the tops of the slope surfaces 471 of the two

rotary shafts

421 and 422 are provided with the flat surfaces 472, the tops of the two

rotary shafts

421 and 422 can be tightly attached together, so as to realize effective closing and reliable sealing of the discharge hole 48. When the spindle 42 is a single-spindle solution as shown in fig. 25, the flat surface 472 at the top of the slope 471 can be tightly fitted with the end of the cylindrical cavity 45 to achieve effective closure and reliable sealing of the discharge port 48.

Alternatively, as shown in fig. 27, the shielding portion 47 may have a hollow area 474 surrounded by a cylindrical side wall 473. This design of the shield 47 on the one hand saves material and on the other hand minimizes any disturbance of the flow of material from the outer end of the shield 47, so that the throughput of material at the outlet 48 is easier to control.

As another example, the curtain portion 47 may be threaded with the cylindrical bore 45. When the rotating shaft 42 rotates, the shielding portion 47 can move along the axial direction of the rotating shaft 42 based on the screw thread, so as to continuously shield the opening 46, thereby achieving the purpose of continuously adjusting the length of the discharge hole 48.

As yet another example, the curtain portion 47 may be a clearance fit with the cylindrical bore 45. The spindle 42 has a threaded connection outside the cylindrical cavity 45, which can be screwed together with the transmission means, so as to push the shutter 47 axially and achieve a continuous adjustment of the discharge orifice 48.

The position or arrangement mode of the feed inlet 43 is not particularly limited in the embodiment of the present application, and the feed inlet can be communicated with the feed delivery passage 49. Several possible arrangements of the feed openings 43 are given below.

As an example, as shown in fig. 5, 24-26, the feed opening 43 may be provided on the housing 41. For example, may be provided on top of the housing 41.

As another example, as shown in fig. 29, it is possible to provide the screw shaft 42 as a hollow screw shaft and provide the hollow passage of the screw shaft 42 as the feed port 43. It should be understood that fig. 29 illustrates a dual-spindle arrangement, and a similar design can be used for a single-spindle arrangement, i.e., the single-spindle 42 is configured as a hollow spindle, and the hollow channel of the single-spindle 42 is configured as the feed port 43.

Alternatively, the inner portion and/or the end surface of the feed opening 43 and/or the feed passage 49 may be rounded. In fact, any turn on the material flow path between the feed inlet 43 and the feed passage 49 may be rounded. Therefore, the materials can flow to the discharge port 48 as smoothly as possible, the materials are prevented from being accumulated in the equipment 4, and the equipment is convenient to clean. For example, if a swivel hollow passageway is used as the feed port 43, referring to FIG. 30, a radiused transition may be used at the interior (e.g., at an interior turn 475) and/or at the end of the hollow passageway of the swivel 42.

As shown in fig. 31, the apparatus 4 may further include a feeding device 410. The feeding device 410 may be connected to the feeding port 43. The drive device 44 may also be used to drive the feeding device 410 so that the material throughput of the discharge opening 48 matches the length of the discharge opening.

The feeding device 410 may be a screw type feeding device as shown in fig. 31 (a), a pneumatic type feeding device as shown in fig. 31 (b), or a piston type feeding device as shown in fig. 31 (c).

In the case that the feeding device 410 is a screw type feeding device, the rotation speed of the screw can be adjusted by the driving device 44, so as to control the material extrusion amount of the discharge port 48; in the case where the feeding device 410 is a pneumatic feeding device, the amount of material extruded from the discharge port 48 can be controlled by adjusting the pressure acting on the material liquid surface; in the case of the feeding device 410 being a piston-type feeding device, the driving device 44 can adjust the moving speed of the piston in the cylindrical feeding hole of the piston, thereby controlling the material extrusion amount of the discharging hole 48.

The material extrusion amount of the discharge port 48 is matched with the length of the discharge port 48, which means that the material extrusion amount of the discharge port 48 is changed in proportion to the length of the discharge port 48.

During actual printing, the amount of material extruded can be determined according to the length of the discharge port 48. Then, the material feeding amount of the feeding device 410 may be controlled so that the material feeding amount is equal to the material extrusion amount.

Fig. 32 is a schematic flowchart of a control method of an apparatus for 3D printing provided in an embodiment of the present application. The apparatus for 3D printing may be the apparatus 4 mentioned above. The control method may be performed by the above-mentioned control device. Therefore, parts not described in detail can be referred to above.

Specifically, the apparatus for 3D printing may include: the inner surface of the shell forms a cylindrical inner cavity, the shell is provided with a plurality of openings extending along the axial direction of the cylindrical inner cavity, and the widths of different openings in the plurality of openings are different; the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, the area which is not shielded by the shielding part in the opening forms a discharge hole, the rotary shaft can rotate around the axis of the cylindrical inner cavity, and the shell can move relative to the rotary shaft; and the feed inlet is communicated with a feed delivery channel enclosed by the outer end surface of the shielding part and the inner surface of the shell.

The control method of fig. 32 may include steps S3210 and S3220.

In step S3210, the housing is controlled to move relative to the rotating shaft, so that different openings of the plurality of openings are covered by the covering portion to form a discharge port.

Step S3220: the rotary shaft is controlled to rotate around the axis of the cylindrical inner cavity so as to continuously change the area of the shielding part for shielding the opening, thereby continuously changing the length of the discharge hole.

Optionally, the opening is a size-adjustable opening; the method further includes step S3230.

Step S3230, adjust the size of the opening so that the length of the opening is the same as the length of the area of the opening that is not blocked by the blocking portion.

Optionally, the housing comprises a first part and a second part, the first part and the second part being relatively slidable in the axial direction; step S3230 may include: the first part and the second part are controlled to relatively slide along the axial direction, so that the length of the opening is the same as the length of an area which is not shielded by the shielding part in the opening.

Optionally, the plurality of openings are arranged along the axial direction of the cylindrical inner cavity; step S3210 may include: the control housing translates axially along the cylindrical bore.

For example, the plurality of openings may be arranged as shown in fig. 4, 10, 14, 15, or 16.

Optionally, the plurality of openings are arranged along the circumferential direction of the cylindrical inner cavity; step S3210 may include: the control housing rotates about the axis of the cylindrical cavity.

For example, the plurality of openings may be arranged as shown in fig. 11, 12, 13, 17, 18, 19, or 20.

Alternatively, step S3220 may include: and controlling the rotary shaft to rotate around the axis of the cylindrical cavity, so that the length of the discharge port is matched with the section line length of the section contour line of a target printing area of the layer to be printed, wherein the target printing area is part or all of the printing area of the layer to be printed.

Alternatively, step S3220 may include: the rotary shaft is controlled to rotate around the axis of the cylindrical inner cavity, so that two ends for limiting the length of the discharge port are aligned with the section contour line of the target printing area in the vertical direction.

Optionally, the method of fig. 32 may further include: relative movement between the housing and the printing platform is controlled such that the two ends defining the length of the discharge orifice are vertically aligned with the cross-sectional contour of the target print zone.

Optionally, the method of fig. 32 may further include: when the length of the longest sectional line of the cross-section contour line of the layer to be printed is less than or equal to the maximum length of the discharge port, determining all printing areas of the layer to be printed as target printing areas; when the length of the longest sectional line of the cross-sectional contour line of the layer to be printed is greater than the maximum length of the discharge port, the entire printing area of the layer to be printed is divided into a plurality of target printing areas.

Optionally, the method of fig. 32 may further include: and controlling the material extrusion amount of the discharge port to ensure that the material extrusion amount of the discharge port is matched with the length of the discharge port.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware or any other combination. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When loaded and executed on a computer, cause the processes or functions described in accordance with the embodiments of the application to occur, in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions may be stored on a computer readable storage medium or transmitted from one computer readable storage medium to another, for example, from one website, computer, server, or data center to another website, computer, server, or data center via wire (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.). The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that incorporates one or more of the available media. The usable medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a magnetic tape), an optical medium (e.g., a Digital Video Disk (DVD)), or a semiconductor medium (e.g., a Solid State Disk (SSD)), among others.

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the implementation. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. An apparatus for 3D printing, comprising:

the inner surface of the shell forms a cylindrical inner cavity, a plurality of openings extending along the axial direction of the cylindrical inner cavity are arranged on the shell, and the width of different openings in the plurality of openings is different;

the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, an area which is not shielded by the shielding part in the opening forms a discharge port, the rotary shaft can rotate around the axis of the cylindrical inner cavity to continuously change the area of the shielding part for shielding the opening so as to continuously change the length of the discharge port, and the shell can move relative to the rotary shaft so that different openings in the plurality of openings are shielded by the shielding part to form the discharge port;

and the feed inlet is communicated with a feed delivery channel enclosed by the outer end surface of the shielding part and the inner surface of the shell.

2. The apparatus of claim 1, wherein the opening is a size-adjustable opening.

3. The apparatus of claim 2, wherein the opening is a continuously adjustable length opening.

4. The apparatus of claim 3, wherein the housing comprises a first portion and a second portion that are relatively slidable in the axial direction to adjust the length of the opening.

5. The apparatus of any one of claims 1-4, wherein the plurality of openings are arranged along an axial direction of the cylindrical inner cavity, and the housing is translatable along the axial direction of the cylindrical inner cavity such that different ones of the plurality of openings are blocked by the blocking portion to form the spout.

6. The apparatus of any one of claims 1-4, wherein the plurality of openings are arranged in a circumferential direction of the cylindrical cavity, and the housing is rotatable about an axis of the cylindrical cavity such that different ones of the plurality of openings are blocked by the blocking portion to form the spout.

7. The apparatus of claim 4, wherein the first portion and the second portion have a first mating surface and a second mating surface therebetween,

the first abutting surface on the first portion includes a first upper step surface, a first lower step surface, a second upper step surface, a first connecting surface connecting the first upper step surface and the first lower step surface, and a second connecting surface connecting the first lower step surface and the second upper step surface, a height difference between the first upper step surface and the first lower step surface is different from a height difference between the first lower step surface and the second upper step surface,

the first mating face on the second portion includes a second lower step face, a third upper step face, a third lower step face, a third connection face connecting the second lower step face and the third upper step face, and a fourth connection face connecting the third upper step face and the third lower step face,

the first upper step surface, the first lower step surface and the second upper step surface are respectively contacted with the second lower step surface, the third upper step surface and the third lower step surface and can relatively slide along the axial direction,

a hollow area formed by the first upper step surface, the first connection surface, the third upper step surface, and the third connection surface is one of the openings, a hollow area formed by the second upper step surface, the fourth connection surface, the third upper step surface, and the second connection surface is another one of the openings,

the second butt-joint surface is a plane surface,

the shell can translate along the axial direction of the cylindrical inner cavity, so that different openings in the plurality of openings are shielded by the shielding part to form the discharge port.

8. The apparatus of claim 4, wherein the first portion and the second portion have a first mating surface and a second mating surface therebetween,

the first abutment surface on the first portion includes a first upper step surface, a first lower step surface, and a first connection surface connecting the first upper step surface and the first lower step surface,

the first abutting surface on the second portion includes a second upper stepped surface, a second lower stepped surface, and a second connecting surface connecting the second upper stepped surface and the second lower stepped surface,

the second abutting surface on the first portion includes a third upper stepped surface, a third lower stepped surface, and a third connecting surface connecting the third upper stepped surface and the third lower stepped surface,

the second abutment surface on the second portion includes a fourth upper step face, a fourth lower step face, and a fourth connection face connecting the fourth upper step face and the fourth lower step face,

the first upper step surface and the first lower step surface are respectively in contact with the second lower step surface and the second upper step surface and can relatively slide along the axial direction, a hollow area formed by the first lower step surface, the first connecting surface, the second lower step surface and the second connecting surface is one opening,

the third upper step surface and the third lower step surface are respectively contacted with the fourth lower step surface and the fourth upper step surface and can relatively slide along the axial direction, a hollow area formed by the third lower step surface, the third connecting surface, the fourth lower step surface and the fourth connecting surface is another opening,

a height difference between the first upper step surface and the first lower step surface is different from a height difference between the third upper step surface and the third lower step surface,

the shell can rotate around the axis of the cylindrical inner cavity, so that different openings in the plurality of openings are shielded by the shielding part to form the discharge port.

9. The apparatus of any one of claims 4, 7 or 8, wherein the first portion is slidable in the axial direction relative to the swivel, and the second portion is fixedly connected to or integrally formed with the swivel.

10. The apparatus of claim 9, wherein the first portion includes two ends defining a length of the first portion in the axial direction, one or both of the two ends of the first portion being a closed circular ring that fits over the swivel.

11. The apparatus of any one of claims 4, 7 or 8, wherein the first portion and the second portion are each slidable relative to the swivel.

12. The apparatus of claim 11, wherein the first portion includes two ends defining a length of the first portion in the axial direction, one of the two ends of the first portion being a closed circular ring fitted over the swivel shaft; and/or the second part comprises two ends limiting the length of the second part along the axial direction, and one end of the two ends of the second part is a closed circular ring sleeved on the rotating shaft.

13. The apparatus of any one of claims 1-12, wherein the housing is moved relative to the swivel such that an opening of the plurality of openings that is to be opened is blocked by the blocking portion to form the spout.

14. The apparatus of claim 13, further comprising:

the first driving device is used for driving the shell to move relative to the rotating shaft, so that the opening needing to be opened in the plurality of openings is shielded by the shielding part to form the discharge hole.

15. The apparatus according to any one of claims 3, 4, 7 or 8, wherein the size of the opening is adjusted such that the length of the opening is the same as the length of the area of the opening not obscured by the obscuration.

16. The apparatus of claim 15, further comprising:

and the second driving device is used for adjusting the size of the opening so that the length of the opening is the same as that of an area which is not shielded by the shielding part in the opening.

17. The apparatus of claim 5 or 7, further comprising:

and the third driving device is used for driving the shell to translate along the axial direction of the cylindrical inner cavity, so that the opening needing to be opened in the plurality of openings is shielded by the shielding part to form the discharge hole.

18. The apparatus of claim 6 or 8, further comprising:

and the fourth driving device is used for driving the shell to rotate around the axis of the cylindrical inner cavity, so that the opening needing to be opened in the plurality of openings is shielded by the shielding part to form the discharge hole.

19. The apparatus of claim 5 or 7, further comprising:

and the seal head is used for axially fixing the rotating shaft.

20. The apparatus of claim 6 or 8, further comprising:

an enclosure for closing off those of the plurality of openings that do not need to be open.

21. The apparatus of claim 5, wherein the housing is an outer shell of the apparatus.

22. The apparatus as claimed in any one of claims 1 to 21, wherein the passage of the opening is of a configuration which gradually narrows in cross-section in the outflow direction of the material to a dimension required for the opening.

23. The apparatus of claim 22, wherein the channel of the opening has a structure that gradually reduces in cross section to a desired width of the opening in the material outflow direction.

24. The apparatus of claim 23, wherein the open channel has a cross-section in a length direction that is a stepped flow passage cross-section or a streamlined flow passage cross-section.

25. The apparatus according to claim 7 or 8, characterized in that the interface between the first part and the second part has a step-like structure in the material outflow direction, so that the passage of the opening is a structure that gradually narrows in cross-section to the desired size of the opening in the material outflow direction.

26. The apparatus of any of claims 14, 16, 17, or 18, further comprising:

control means for controlling the drive means in the apparatus.

27. A control method of an apparatus for 3D printing, characterized in that the apparatus for 3D printing comprises:

the rotary shaft is provided with a shielding part arranged at the shaft end of the rotary shaft, the shielding part is positioned in the cylindrical inner cavity to shield an area in the opening, an area which is not shielded by the shielding part in the opening forms a discharge hole, the rotary shaft can rotate around the axis of the cylindrical inner cavity, and the shell can move relative to the rotary shaft;

the feed inlet is communicated with a material conveying channel enclosed by the outer end surface of the shielding part and the inner surface of the shell;

the control method comprises the following steps:

controlling the shell to move relative to the rotating shaft, so that different openings in the plurality of openings are shielded by the shielding part to form the discharge hole;

the rotary shaft is controlled to rotate around the axis of the cylindrical inner cavity so as to continuously change the area of the opening shielded by the shielding part, and thus the length of the discharge hole is continuously changed.

28. The control method of claim 27, wherein the opening is a size-adjustable opening;

the method further comprises the following steps:

adjusting the size of the opening so that the length of the opening is the same as the length of the area of the opening that is not blocked by the blocking portion.

29. The control method according to claim 28, wherein the housing includes a first portion and a second portion that are relatively slidable in the axial direction,

the adjusting the size of the opening comprises:

controlling the first part and the second part to relatively slide along the axial direction, so that the length of the opening is the same as the length of an area which is not shielded by the shielding part in the opening.

30. The control method of any one of claims 27-29, wherein the plurality of openings are arranged along an axial direction of the cylindrical lumen;

the controlling the shell to move relative to the rotating shaft comprises:

controlling axial translation of the housing along the cylindrical lumen.

31. The control method of any one of claims 27-29, wherein the plurality of openings are arranged in a circumferential direction of the cylindrical lumen;

the controlling the shell to move relative to the rotating shaft comprises:

controlling the housing to rotate about the axis of the cylindrical cavity.