Patent Description:
The present application relates to a field of 3D printing, more particularly, to a device for 3D printing and a control method thereof.

Fused deposition modeling (fused deposition modeling, FDM) technology is a common 3D printing technology. The FDM technology generally involves heating material to a fused state (or a semi-flow state), and extruding the fused material from a discharge port (or an extrusion port) of a 3D printing head, and the material is deposited layer by layer on a printing platform to form a 3D article.

The conventional 3D printing head has a feeding portion and a nozzle for forming a discharge port. The nozzle is typically mounted at a lower end of the feeding portion, resulting in a less compact structure of a device.

Document <CIT> discloses a nozzle unit of a 3D printer which includes a plurality of nozzles and can greatly increase the fused deposition printing speed.

The present invention is defined by the device of claim <NUM> and carried out by the method of claim <NUM>.

The present application provides a device for 3D printing and a control method thereof, which can make the structure of the device more compact.

In a first aspect, provided is a device for 3D printing, including: a feeding pipe, wherein an opening extending along an axial direction of the feeding pipe is disposed on an outer wall of the feeding pipe; and a sleeve sleeved on the feeding pipe, wherein a discharge port in communication with the opening is disposed on an outer wall of the sleeve, the sleeve is capable of rotating around an axis of the feeding pipe relative to the feeding pipe, so as to make the discharge port and the opening communicate or no longer communicate; a passage of the discharge port is a structure in which a section along material outflow direction gradually shrinks to a required size of the discharge port, the discharge port is a discharge port with a continuously adjustable size, and the discharge port being suitable for performing a continuous printing along a cross-sectional contour line of a target printing region; and the outer wall of the sleeve comprises a first portion and a second portion, the first portion and the second portion are slidable relative to each other along the axial direction to adjust the length of the discharge port.

In a second aspect, provided is a control method of a device for 3D printing, where the device for 3D printing includes: a feeding pipe, wherein an opening extending along an axial direction of the feeding pipe is disposed on an outer wall of the feeding pipe; a sleeve sleeved on the feeding pipe, wherein a discharge port in communication with the opening is disposed on an outer wall of the sleeve, the sleeve is capable of rotating around an axis of the feeding pipe relative to the feeding pipe; a passage of the discharge port is a structure in which a section along material outflow direction gradually shrinks to a required size of the discharge port, the discharge port is a discharge port with a continuously adjustable size, and the discharge port performs a continuous printing along a cross-sectional contour line of a target printing region; the outer wall of the sleeve comprises a first portion and a second portion, the first portion and the second portion are slidable relative to each other along the axial direction to adjust the length of the discharge port; and the control method includes: controlling the sleeve to rotate around the axis of the feeding pipe relative to the feeding pipe, so as to make the discharge port and the opening communicate or no longer communicate.

In a third aspect, provided is a computer readable storage medium having stored thereon instructions for performing the control method of the second aspect.

In a fourth aspect, provided is a computer program product including instructions for performing the control method of the second aspect.

In contrast to the conventional design (a nozzle is disposed at the bottom of a feeding portion), the present application utilizes a sleeve to provide a discharge port, by assembling the sleeve and the feeding pipe together, making the overall structure of a device more compact; in addition, printing suspension is realized by rotating a sleeve around an axis of a feeding pipe relative to the feeding pipe, which can achieve a quick response to the printing suspension.

For ease of understanding, a brief introduction to a conventional 3D printing device is first provided.

As shown in <FIG>, a conventional 3D printing device <NUM> may generally include a feeding apparatus <NUM>, a 3D printing head <NUM>, a printing platform <NUM> and a control apparatus <NUM> (the above structure division manner is merely an example, and in fact, other structural division manners may also be adopted. For example, the control apparatus and/or the feeding apparatus <NUM> may belong to a part of the 3D printing head <NUM>).

The feeding apparatus <NUM> may be connected to a scroll <NUM>. In an actual printing process, the feeding apparatus <NUM> may take a filamentous material from the scroll <NUM>, and convey the filamentous material to the 3D printing head <NUM>. Material used in a 3D printing process is generally a thermoplastic material, such as a high-molecular polymer, a low-melting-point metal, or other materials that can be formulated as flowable pastes (such as paste-like ceramic, high-melting-point metal powder mixtures, cement or the like).

As shown in <FIG>, the 3D printing head <NUM> may generally include a feeding portion <NUM>, a nozzle <NUM> and a temperature control apparatus <NUM>. The temperature control apparatus <NUM> is generally disposed outside the feeding portion <NUM> and configured to heat material conveyed by the feeding apparatus <NUM> to the feeding portion <NUM> to a molten state. The temperature control apparatus <NUM> may be, for example, a heating apparatus. The nozzle <NUM> is mounted at the lower end of the feeding portion <NUM>. The nozzle may provide a discharge port <NUM>, and thus may extrude the material in a molten state conveyed by the feeding portion <NUM> onto the printing platform <NUM>.

The control apparatus <NUM> may be configured to control the 3D printing head <NUM> to print an article layer by layer. During a process of printing each layer, the 3D printing head <NUM> may be controlled to completely print all of a printing region of a layer to be printed (that is, the whole region enclosed by a cross-sectional contour line of the layer to be printed) according to a preset printing path.

An overall process of conventional 3D printing is generally as follows.

Before an article is printed, a 3D model of the article may be created by using modeling software. The modeling software may be, for example, computer aided design (computer aided design, CAD) software. Then, a layer processing is performed on the created 3D model, so as to divide the 3D model into multiple layers to be printed and obtain layer data of each layer to be printed. The layer processing of a 3D model is considered as decomposing a 3D article printing process into many 2D printing processes, and the printing process of each layer to be printed is similar to a planar 2D printing process. After obtaining the layer data of each layer to be printed, the control apparatus <NUM> may control the 3D printing head <NUM> to move along a certain filling path according to the layer data of each layer to be printed, and in a process of movement, the material in a molten state is extruded onto the printing platform <NUM> through the discharge port <NUM> to print or fill a printing region of each layer to be printed. After all layers to be printed of the article are printed, the material is solidified layer by layer to form a 3D article.

For ease of understanding, a printing process of a certain layer to be printed by the conventional 3D printing device will be described in detail below by taking <FIG> as examples.

Referring to <FIG>, a printing region of a layer to be printed is region <NUM>, and a cross-sectional contour line of the region <NUM> is cross-sectional contour line <NUM>.

In order to completely print the region <NUM>, the region <NUM> is generally divided into a plurality of closely arranged passes based on the cross-sectional contour line <NUM>, such as pass A<NUM> to pass A<NUM> shown in <FIG>.

In a process of printing, the control apparatus <NUM> controls a z-coordinate of the 3D printing head <NUM> to be unchanged, and controls the 3D printing head <NUM> to completely print all passes in a certain order, for example, printing the passes A<NUM>- A<NUM> in sequence along a straight path in a parallel reciprocation manner.

For example, in a case of a printing process of pass A<NUM>, the control apparatus <NUM> may first move the 3D printing head <NUM> to a position above position point p1 shown in <FIG>, and then control the 3D printing head <NUM> to move from the position above the position point p1 to a position above position point p2. During a movement process, material in a molten state is extruded onto the pass A<NUM> through the discharge port <NUM>, so as to print the pass A<NUM>. A printing manner of other passes is similar, and will not be described redundantly herein. After all the passes are printed, a printing process of the layer to be printed is completed, and the 3D printing head <NUM> or the work platform <NUM> may be controlled to move along the z-axis direction to prepare printing of a next layer.

As previously described, the conventional 3D printing head <NUM> has a feeding portion <NUM> and a nozzle <NUM> for providing a discharge port <NUM>. The nozzle <NUM> is typically mounted at the lower end of the feeding portion <NUM>, resulting in a less compact structure of the 3D printing head <NUM>.

A device for 3D printing provided by an embodiment of the present application will be described in detail below. It should be noted that the device 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>, a device <NUM> for 3D printing may include a feeding pipe <NUM> and a sleeve <NUM>. The sleeve <NUM> may be sleeved on the feeding pipe <NUM> to form a sleeve joint assembly that is compact in structure.

Referring to <FIG>, an opening <NUM> is disposed on an outer wall of the feeding pipe <NUM> (the opening may extend, for example, along an axial direction of the feeding pipe <NUM>).

In some embodiments, the feeding pipe <NUM> may belong to one of the entire feeding portion of the device <NUM>. In addition to the feeding pipe <NUM>, the feeding portion may also include other portions in communication with the feeding pipe <NUM>.

In other embodiments, the feeding pipe <NUM> is a feeding portion of the device <NUM>, and a feed port <NUM> may be disposed on an end surface of the feeding pipe <NUM> or on the outer wall of the feeding pipe <NUM>.

An interior of the feeding pipe <NUM> (hereinafter referred to as a feeding passage) may be of an arc design. For example, referring to <FIG>, the feeding passage may be designed as a cylindrical passage. Moreover, in some embodiments, an arc transition is also adopted between the cylindrical passage and its ends. The feeding passage adopts an arc design, which not only enables a molten material to be smoothly conveyed in the feeding passage, but also facilitates the cleaning of the feeding passage, and avoids material waste due to retention in the interior of the feeding passage as much as possible.

The sleeve <NUM> may be sleeved on the feeding pipe <NUM>, that is, the feeding pipe <NUM> may be seen as an inner pipe of the sleeve <NUM>. A discharge port <NUM> that may be in communication with the opening <NUM> is disposed on the outer wall of the sleeve <NUM>. In some embodiments, similar to the opening <NUM>, the discharge port <NUM> may also extend along the axial direction of the feeding pipe <NUM>, that is, a length direction of the discharge port <NUM> may be the axial direction of the feeding pipe <NUM>. The outer wall of the sleeve <NUM> may be provided with one discharge port <NUM>, or may be provided with a plurality of discharge ports <NUM>. For example, the outer wall of the sleeve <NUM> may be provided with two discharge ports, three discharge ports, four discharge ports, and eight discharge ports. The sleeve <NUM> is movable relative to the feeding pipe <NUM> such that the opening <NUM> is capable of being in communication with different discharge ports <NUM> (that is, realizing a switch between the different discharge ports <NUM>).

The sleeve <NUM> is capable of rotating around an axis of the feeding pipe <NUM> relative to the feeding pipe, so as to make the discharge port <NUM> and the opening <NUM> communicated or no longer communicated.

For example, the sleeve <NUM> is capable of rotating around the axis of the feeding pipe <NUM> relative to the feeding pipe, so as to make the discharge port <NUM> no longer be in communication with the opening <NUM> when printing is required to be suspended to block a material conveying passage, thus realizing printing suspension.

An example will be described in conjunction with <FIG>. Two discharge ports <NUM> are shown schematically in <FIG>. In order to distinguish rather than limit, the two discharge ports are recorded as discharge port <NUM>(<NUM>) and discharge port <NUM>(<NUM>) respectively. Assuming that the discharge port <NUM>(<NUM>) is initially in communication with the opening <NUM>, as shown on the left in <FIG>, the discharge port <NUM>(<NUM>) is in communication with the opening <NUM>, the sleeve <NUM> may rotate an angle around the axis of the feeding pipe <NUM> relative to the feeding pipe (rotating an angle clockwise in the example in <FIG>), so as to make the discharge port <NUM>(<NUM>) no longer be in communication with the opening <NUM>, as shown on the right in <FIG>, to block the material conveying passage, thus realizing printing suspension.

Therefore, the device <NUM> provided by an embodiment of the present application can realize printing suspension by rotating the sleeve around the axis of the feeding pipe relative to the feeding pipe, which can achieve a quick response to the printing suspension.

For example, the sleeve <NUM> may be capable of rotating a relative small angle around the axis of the feeding pipe <NUM> relative to the feeding pipe, so as to make the discharge port <NUM> and the opening <NUM> communicated or no longer communicated. For example, the relative small angle refers to a smallest angle that can make the discharge port <NUM> communicated with the opening <NUM> to no longer communicated.

As an example, when printing is required to be suspended, assuming that a first angle of the sleeve <NUM> minimum rotating around the axis of the feeding pipe <NUM> relative to the feeding pipe can make the discharge port <NUM> no longer be in communication with the opening <NUM>, then the sleeve <NUM> may rotate the first angle around the axis of the feeding pipe <NUM> relative to the feeding pipe to make the discharge port <NUM> no longer be in communication with the opening <NUM>.

In this example, when printing is required to be started later, the sleeve <NUM> may reverse rotate the first angle around the axis of the feeding pipe <NUM> relative to the feeding pipe to make the discharge port <NUM> be in communication with the opening <NUM>, thus resuming printing quickly.

It is often necessary to suspend the printing process during 3D printing. For example, it is necessary to suspend printing process when printing to contour edge of a target printing region, and wait until the printing head is moved to a new printing starting point before continuing the printing process. A 3D printing extrusion material is usually a high viscosity substance, for example, with a viscoelastic property of a polymer material. When a material conveying apparatus stops conveying the printing material, flow of the material will not stop suddenly, then the printing material will continue to accumulate outside the contour edge of the target printing area, which will destroy a shape of the cross-sectional contour line of the target printing area, resulting in reduced geometric accuracy of the printing article.

The device <NUM> provided by an embodiment of the present application, during 3D printing, when printing reaches the contour edge of the target printing area and is required to be suspended, the sleeve <NUM> may rotate a relative small angle around the axis of the feeding pipe <NUM> relative to the feeding pipe when the material conveying apparatus stops conveying the printing material, so as to make the discharge port <NUM> no longer be in communication with the opening <NUM> to block the material conveying passage, such that the printing material can quickly respond to an instruction of a control system and stop outflowing from the discharge port <NUM>.

Therefore, the device <NUM> provided by an embodiment of the present application can realize a quickly response to printing suspension.

In some embodiments, the sleeve <NUM> may rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe when printing is required to be started, so as to make the discharge port <NUM> be in communication with the opening <NUM> to open the material conveying passage and realize printing starting.

An example will be described in conjunction with <FIG> again. Assuming that the discharge port <NUM>(<NUM>) is not initially in communication with the opening <NUM>, as shown on the right in <FIG>, the sleeve <NUM> may rotate an angle around the axis of the feeding pipe <NUM> relative to the feeding pipe (rotating an angle anticlockwise in the example in <FIG>), so as to make the discharge port <NUM>(<NUM>) be in communication with the opening <NUM>, as shown on the left in <FIG>, to open the material conveying passage, thus realizing printing starting.

The device <NUM> provided by an embodiment of the present application can realize printing starting by rotating the sleeve <NUM> around the axis of the feeding pipe <NUM> relative to the feeding pipe, which can achieve a quick response to the printing starting.

A rotation of the sleeve <NUM> around the axis of the feeding pipe <NUM> relative to the feeding pipe may be achieved by means of a drive apparatus. As shown in <FIG>, the device <NUM> may include a drive apparatus <NUM>.

The drive apparatus <NUM> may be configured to drive the sleeve <NUM> to rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe, so as to make the discharge port <NUM> and the opening <NUM> communicated or no longer communicated.

For example, the drive apparatus <NUM> may be configured to drive the sleeve <NUM> to rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe when printing is required to be suspended, so as to make the discharge port <NUM> no longer be in communication with the opening <NUM>.

For another example, the drive apparatus <NUM> may be configured to drive the sleeve <NUM> to rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe when printing is required to be started, so as to make the discharge port <NUM> be in communication with the opening <NUM>.

The drive apparatus <NUM> may be specifically implemented in a variety of manners, which is not limited in the embodiment of the present application, and may be, for example, a rack and pinion mechanism or a crank slider mechanism.

In some embodiments, the discharge port <NUM> may always be in communication with the opening <NUM>. For example, the discharge port <NUM> may be fixed below the opening <NUM>. The sleeve <NUM> may rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe when printing is required to be suspended, so as to make the discharge port <NUM> no longer be in communication with the opening <NUM>.

In some embodiments, the sleeve <NUM> may be movable relative to the feeding pipe <NUM> such that the discharge port <NUM> may move below the opening <NUM> to be in communication with the opening <NUM>. The sleeve <NUM> may rotate around the axis of the feeding pipe <NUM> relative to the feeding pipe when printing is required to be suspended, so as to make the discharge port <NUM> no longer be in communication with the opening <NUM>.

In some embodiments, the sleeve <NUM> may be a one-piece sleeve, such as an integrally formed sleeve. In other embodiments, the sleeve <NUM> may be a separate sleeve, that is, an outer wall of the sleeve <NUM> may include a plurality of separable portions, or an outer wall of the sleeve <NUM> may be spliced from a plurality of separable portions.

As shown in <FIG>, the outer wall of the sleeve <NUM> may include a first portion <NUM> and a second portion <NUM> that are separable. The first portion <NUM> may be assembled with the feeding pipe <NUM> in the manner shown in <FIG>. The second portion <NUM> may have a complementary structure to the first portion <NUM>, and the two are spliced together in the manner shown in <FIG> to form the outer wall of the sleeve <NUM>.

In some embodiments, the outer wall of the sleeve <NUM> may also be assembled from three or more separable portions. For example, in <FIG>, the outer wall of the sleeve <NUM> includes a first portion <NUM>, a second portion <NUM>, a third portion <NUM> and a fourth portion <NUM> that are separable, edges of which are spliced to each other to form the outer wall of the sleeve <NUM>.

The sleeve <NUM> may be fixed to the feeding pipe <NUM> or movable relative to the feeding pipe <NUM>. For example, the sleeve <NUM> may move along an axial direction of the feeding pipe <NUM>; for another example, the sleeve <NUM> may rotate around an axis of the feeding pipe <NUM>; and for yet another example, the sleeve <NUM> may not only move along an axial direction of the feeding pipe <NUM>, but also rotate around an axis of the feeding pipe <NUM>.

The discharge port <NUM> is a discharge port with an adjustable size. The adjustable size of the discharge port <NUM> may refer that a length of the discharge port <NUM> is continuously adjustable, or a width of the discharge port <NUM> is continuously adjustable, or both length and width of the discharge port <NUM> are continuously adjustable.

The discharge port <NUM> is designed as a discharge port with an adjustable size.

According to an example not covered by the claims, one or more shutters may be provided at the discharge port <NUM> to adjust the size of the discharge port <NUM>.

According to the invention, the sleeve <NUM> includes plurality of separable portions. Abutting faces of the plurality of portions may form a plurality of discharge ports, and the plurality of portions are movable relative to each other ( moveable along the axial direction of the feeding pipe <NUM>) to adjust the size of the discharge port <NUM>.

According to the invention, in <FIG>, the sleeve <NUM> includes a first portion <NUM> and a second portion <NUM>. The first portion <NUM> and the second portion <NUM> are slidable relative to each other along the axial direction of the feeding pipe <NUM> so as to form the discharge port <NUM> with a continuously adjustable length.

Shapes of the first portion <NUM> and the second portion <NUM> and manners in which they form the discharge port <NUM> may be various.

As an example, as shown in <FIG>, the first portion <NUM> may include a first upper stepped surface <NUM>, a first lower stepped surface <NUM> and a first connecting surface <NUM> connecting the first upper stepped surface <NUM> and the first lower stepped surface <NUM>. The second portion <NUM> may include a second upper stepped surface <NUM>, a second lower stepped surface <NUM> and a second connecting surface <NUM> connecting the second upper stepped surface <NUM> and the second lower stepped surface <NUM>. The first upper stepped surface <NUM> is in contact with the second lower stepped surface <NUM>, and the two are slidable relative to each other along the axial direction of the feeding pipe <NUM> (in other words, the first upper stepped surface <NUM> and the second lower stepped surface <NUM> are in slidable connection along the axial direction of the feeding pipe <NUM>). The first lower stepped surface <NUM> is in contact with the second upper stepped surface <NUM>, and the two are slidable relative to each other along the axial direction of the feeding pipe <NUM> (in other words, the first lower stepped surface <NUM> and the second upper stepped surface <NUM> are in slidable connection along the axial direction of the feeding pipe <NUM>). A hollow area formed by the first lower stepped surface <NUM>, the first connecting surface <NUM>, the second lower stepped surface <NUM> and the second connecting surface <NUM> may thus serve as the discharge port <NUM>.

In this example, the first portion <NUM> and the second portion <NUM> are abutted together using a staggered complementary stepped structure, and the two are slidable relative to each other along the axial direction of the feeding pipe <NUM> to form the discharge port <NUM> with a continuously adjustable length. The width of the discharge port <NUM> depends on a difference in height between the first upper stepped surface <NUM> and the first lower stepped surface <NUM> (or the second upper stepped surface <NUM> and the second lower stepped surface <NUM>). The implementation manner of such a discharge port can form a discharge port <NUM> having a small width on the premise of ensuring the size and strength of the first portion <NUM> and the second portion <NUM> (the width of the discharge port can affect printing accuracy).

As another example, the first portion <NUM> and the second portion <NUM> may have a concave-convex complementary structure. The relative sliding of the first portion <NUM> and the second portion <NUM> along the axial direction of the feeding pipe <NUM> may change a relative positional relationship between concave-convex portions, and a hollow area between the concave-convex portions may thus form the discharge port <NUM>.

The above indicates that the first portion <NUM> and the second portion <NUM> are slidable relative to each other along the axial direction of the feeding pipe <NUM>. It should be noted that not both the first portion <NUM> and the second portion <NUM> are required to be slidable relative to the feeding pipe <NUM> in the embodiment of the present application.

As one possible implementation manner, both the first portion <NUM> and the second portion <NUM> are slidable relative to the feeding pipe <NUM>.

As another possible implementation manner, as shown in <FIG>, the first portion <NUM> is slidable relative to the feeding pipe <NUM>, and the second portion <NUM> is fixedly connected to the feeding pipe <NUM> or integrally formed with the feeding pipe <NUM>. This implementation manner can simplify the control of the device <NUM>.

As shown in <FIG> or <FIG>, in some embodiments, an end <NUM> of the first portion <NUM> may be designed as a closed ring sleeved on the feeding pipe <NUM>; and/or an end <NUM> of the second portion <NUM> (the end <NUM> and the end <NUM> may define a length of the sleeve <NUM> along the axial direction) may be designed as a closed ring sleeved on the feeding pipe <NUM>. This could enhance the overall rigidity and tightness of the sleeve <NUM>.

In some embodiments, when the first portion <NUM> is a sliding part and the second portion <NUM> is a fixing part, as shown in <FIG>, two ends of the first portion <NUM> may be designed as closed rings. This could enhance the overall rigidity and tightness of the sleeve <NUM>.

The relationship between the size of the discharge port <NUM> and the size of the opening <NUM> is not specifically limited in the embodiment of the present application. The size of the discharge port <NUM> may be the same as or different from the size of the opening <NUM>.

For example, the length of the discharge port <NUM> (when the discharge port <NUM> is a discharge port with an adjustable length, the length of the discharge port <NUM> may refer to the maximum length of the discharge port <NUM>) may be less than the length of the opening <NUM>; for another example, the width of the discharge port <NUM> (when the discharge port <NUM> is a discharge port with an adjustable width, the width of the discharge port <NUM> may refer to the maximum width of the discharge port <NUM>) may be less than the width of the opening <NUM>.

The adjustment of the size of the discharge port <NUM> may be achieved by means of a drive apparatus. For example, in <FIG>, a support <NUM> for fixing the first portion <NUM> and a support <NUM> for fixing the second portion <NUM> may be disposed on the sleeve <NUM>. A drive apparatus <NUM> may provide the support <NUM> and the support <NUM> with power of movement along the axial direction of the feeding pipe <NUM>, so that the first portion <NUM> is driven to move along the axial direction by the support <NUM>, and the second portion <NUM> is driven to move along the axial direction by the support <NUM>.

As described above, the outer wall of the sleeve <NUM> may be provided with one discharge port <NUM>, or may be provided with a plurality of discharge ports <NUM>. For example, the outer wall of the sleeve <NUM> may be provided with two discharge ports, three discharge ports, four discharge ports, and eight discharge ports. The sleeve <NUM> is movable relative to the feeding pipe <NUM> such that the opening <NUM> is capable of being in communication with different discharge ports <NUM> (that is, realizing a switch between the different discharge ports <NUM>).

As an example, the plurality of discharge ports <NUM> may be arranged along the axial direction of the feeding pipe <NUM>. In this case, the sleeve <NUM> may be translated along the axial direction of the feeding pipe <NUM> such that the opening <NUM> is capable of being in communication with different discharge ports <NUM>.

As another example, the plurality of discharge ports <NUM> may be arranged along a circumferential direction of the sleeve <NUM>. In this case, the sleeve <NUM> is rotatable around an axis of the feeding pipe <NUM> such that the opening <NUM> is capable of being in communication with different discharge ports <NUM>. In order to achieve rotation of the sleeve <NUM> around the axis of the feeding pipe <NUM>, the device <NUM> may also be designed with a corresponding drive apparatus. The drive apparatus may be, for example, a gear transmission mechanism.

Of course, a combination of the above two examples is also possible.

Hereinafter, with reference to <FIG>, <FIG>, <FIG> and <FIG>, exemplary description is made to a manner in which a plurality of discharge ports <NUM> are formed on an outer wall of a sleeve <NUM> in detail.

As one possible implementation manner, referring to <FIG>, the sleeve <NUM> may include a first portion <NUM> and a second portion <NUM>. The first portion <NUM> and the second portion <NUM> are similar to the first portion <NUM> and the second portion <NUM> shown in <FIG>, except that in <FIG>, two abutting faces of the first portion <NUM> and the second portion <NUM> are both stepped abutting faces, and specifically, stepped abutting faces 611a, 612a and 613a of the first portion <NUM> and the corresponding faces of the second portion are used to form a discharge port 65a; and stepped abutting face 611b, 612b and 613b of the first portion <NUM> and the corresponding faces of the second portion are used to form a discharge port 65b.

As another possible implementation manner, referring to <FIG>, the sleeve <NUM> is formed by splicing four portions <NUM>, <NUM>, <NUM>, <NUM>, and each two adjacent portions form a discharge port, and a total of four discharge ports 65a, 65b, 65c, 65d are formed. Of course, in some embodiments, abutting faces of two adjacent portions may also be designed as a plane, so that a discharge port will not be formed between the two adjacent portions, and furthermore, any number of discharge ports can be designed according to actual needs (for example, an odd number of discharge ports can be designed, or an even number of discharge ports can be designed).

Sizes of a plurality of discharge ports <NUM> are not specifically limited in the embodiment of the present application. The plurality of discharge ports <NUM> may be discharge ports of the same size (if the discharge ports <NUM> are discharge ports with adjustable sizes, the same size may refer that the maximum sizes of the discharge ports <NUM> are the same), or discharge ports of different sizes.

As an example, lengths (or maximum lengths) of the plurality of discharge ports <NUM> are different.

As another example, widths of the plurality of discharge ports <NUM> are different. The widths of the discharge ports <NUM> affect a width of an extruded material, which in turn affects accuracy of 3D printing. The plurality of discharge ports <NUM> with different widths are designed so that the device <NUM> can select the discharge ports with different levels of accuracy for printing according to actual needs.

For example, assuming that a layer to be printed includes a first printing region in which a cross-sectional contour line changes sharply in a vertical direction and a second printing region in which a cross-sectional contour line changes gently in the vertical direction, when the device <NUM> is used to print the first printing region, it can be switched to a discharge port with a smaller width, thereby improving printing accuracy; and when the device <NUM> is used to print the second printing region, it can be switched to a discharge port with a larger width, thereby improving printing efficiency on the premise of printing accuracy.

Of course, the combination of the above cases is also possible, that is, widths and lengths (or the maximum lengths) of the plurality of discharge ports <NUM> are all different.

As indicated above, the discharge port <NUM> provided by the embodiment of the present application may be a discharge port <NUM> with a continuously adjustable length. Compared with design of a discharge port of a conventional 3D printing head, the discharge port <NUM> is designed as a discharge port with the continuously adjustable length, which overcomes the limitation of the conventional discharge port design concept, and has obvious advantages and broad application prospects. The following is an analysis of this.

A discharge port of a conventional 3D printing head is generally designed as a nozzle in a fixed shape. A common shape of the nozzle includes a round hole, a square hole, or a slightly deformed irregular shaped hole with equal diameter. A diameter of the nozzle is generally about <NUM>, and a common diameter is <NUM>. When an article is required to be high in printing accuracy, a nozzle with a small diameter is generally selected. Such type of nozzle has less the amount of the material extrusion per unit time and is lower in printing efficiency. When an article is required to be high in printing efficiency, a nozzle with a large diameter is generally selected. Such type of nozzle prints an article in a rough shape and is lower in printing accuracy. Thus it can be seen that the conventional 3D printing head cannot take both printing efficiency and printing accuracy of 3D printing into account. A formation process of such design manner of a conventional discharge port is analyzed below.

A 3D printing technology is a more advanced manufacturing technology developed on the basis of a 2D printing technology. Generally, before 3D printing, it usually needs to perform layer processing on a 3D model of an article to be printed. The layer processing is equivalent to decomposing a 3D article printing process into many 2D printing processes, that is, a printing process of each layer may be considered as a planar printing process. Therefore, a conventional 3D printing device follows many design concepts of a 2D printing device. Most obviously, a discharge port of a 2D printing head generally adopts a nozzle in a fixed shape. A discharge port of a 3D printing head, following the design manner of the discharge port of the 2D printing head, is also designed as a nozzle in a fixed shape. As mentioned above, the design of such type of nozzle results in that 3D printing head cannot take both printing efficiency and printing accuracy into account, and becomes a key obstacle to the development of the 3D printing technology.

A discharge port <NUM> in an embodiment of the present application is designed as a discharge port with a continuously adjustable length within a certain range. This is a design based on a full consideration of characteristics of a 3D printing object. Compared with the conventional 3D printing device, a 3D printing device provided by an embodiment of the present application makes it possible to take both efficiency and accuracy of 3D printing into account, and is more suitable for 3D printing. Specific illustration is as follows.

A 2D printing object is generally small in size, and the printing object is mainly a text or an image. The text or image may be freely arranged in a two dimensional plane and there is no rule to follow. Therefore, it is common to design a discharge port of a 2D printing device as a nozzle in a fixed shape, and such design is reasonable in the field of 2D printing. Different from the 2D printing object, a 3D printing object is generally a 3D article for practical usage. Since the 3D article has a certain physical contour, an intercept line of the 3D article along one section is generally one or more closed and continuously changing curves. Making full use of such characteristic of the 3D printing object, the embodiment of the present application designs a discharge port <NUM> as a discharge port with a continuously adjustable length. The continuous adjustment of the length of the discharge port <NUM> coincides with the characteristic that a cross-sectional contour line of the 3D printing object is closed and continuously changing. Such discharge port <NUM> is more suitable for 3D printing, making it possible to greatly increase the printing efficiency.

According to the invention, with a discharge port provided by the embodiment of the present application, continuous printing is performed along a cross-sectional contour line. During printing, the discharge port <NUM> is controlled to change according to changes of the cross-sectional contour line. It should be understood that compared to a manner of conventional printing on a pass-by-pass basis, printing along the cross-sectional contour line has ultrahigh printing efficiency.

Further, a width of the discharge port <NUM> may be set as a fixed small value, enabling printing accuracy of a 3D article to maintain unchanged and at a higher accuracy. The printing accuracy is maintained unchanged during continuous change of the discharge port <NUM>, which is difficult to be realized by a conventional 3D printing head. Therefore, a discharge port with a continuously adjustable length provided by an embodiment of the present application makes it possible to take both printing efficiency and printing accuracy of 3D printing into account, and is more suitable for the 3D printing.

Hereinafter, with reference to specific embodiments, exemplary description is made to a changing manner of the length of the discharge port <NUM> in detail.

Optionally, the length of the discharge port <NUM> may be controlled to continuously change according to a shape of a target printing region (or the length of the discharge port <NUM> may be controlled to change with a change of the shape of the target printing region), and the target printing region may be part of a printing region of a layer to be printed or all of the printing region of the layer to be printed.

For example, in some embodiments, the size of the discharge port <NUM> may be adjusted such that the length of the discharge port <NUM> matches lengths of intercept line segments of a cross-sectional contour line of a target printing region of a layer to be printed.

For another example, in some embodiments, the size of the discharge port <NUM> may be adjusted such that two ends of the discharge port <NUM> are aligned with the cross-sectional contour line of the target printing region in a vertical direction.

When the two ends of the discharge port <NUM> are aligned with the cross-sectional contour line of the target printing region in the vertical direction, projection of the two ends of the discharge port <NUM> in the vertical direction will fall on the intercept line segments of the cross-sectional contour line of the target printing region. For convenience of description, this printing method will hereinafter be referred to as tracking printing of the cross-sectional contour line of the target printing region.

The tracking printing will be described in more detail below with reference to <FIG>.

Referring to <FIG>, reference sign <NUM> denotes a target printing region of a layer to be printed, and a length of the discharge port <NUM> extends along an x direction. During printing of the target printing region <NUM>, the device <NUM> may be controlled to move generally towards a y direction. During the movement of the device <NUM>, the length and/or position of the discharge port <NUM> are changed in real time such that two ends of the discharge port <NUM> are always aligned with a cross-sectional contour line of the target printing region <NUM> in a vertical direction z (perpendicular to an x-y plane), that is, projection of the two ends of the discharge port <NUM> in the vertical direction z always falls on the cross-sectional contour line of the target printing region <NUM>.

For example, assuming that y coordinate of the current position of the discharge port <NUM> is y1, and the cross-sectional contour line of the target printing region <NUM> is transected at y1 along the x direction to obtain two points (x1, y1) and (x2, y1), positions of two ends of the discharge port <NUM> can be changed such that the first end is located directly above (x1, y1) and the second end is located directly above (x2, y1), and further, accurate tracking printing can be performed on the cross-sectional contour line of the target printing region <NUM>.

The tracking printing of the cross-sectional contour line of the target printing region may be implemented in a variety of manners. Optionally, as a first implementation manner, the positions of two ends of the discharge port <NUM> may be adjusted such that the two ends of the discharge port <NUM> are aligned with the cross-sectional contour line of the target printing region in the vertical direction.

Optionally, as a second implementation manner, the size of the discharge port <NUM> may be adjusted such that the length of the discharge port <NUM> matches the lengths of the intercept line segments of the cross-sectional contour line of the target printing region of the layer to be printed; and a relative position between the feeding pipe <NUM> and the sleeve <NUM> as a whole and the printing platform is adjusted by using a drive apparatus such that two ends of the discharge port <NUM> are aligned with the cross-sectional contour line of the target printing region in a vertical direction.

In the process of printing the target printing region, the device <NUM> may implement tracking printing by using one of the above two implementation manners according to actual needs; or, different tracking printing methods may also be used when different parts of the target printing region are printed.

For example, the target printing region may include a portion having a shorter length of the intercept line segment and a portion having a longer length of the intercept line segment. When a portion with a short length of the intercept line segment is printed, the first implementation manner may be used for tracking printing to simplify the control of the device <NUM>; and when a portion with a longer length of the intercept line segment is printed, the second implementation manner may be used for tracking printing.

Compared with an article printed by a conventional discharge port, a cross-sectional contour line of a target printing region is tracked and printed, and the printed article also has a significant improvement in mechanical properties and shape uniformity. Referring to <FIG> and <FIG>, detailed illustration is given thereto.

Conventional 3D printing is generally performed on a pass-by-pass basis according to a certain pass sequence. Since a size of a discharge port of a conventional 3D printing device is small (a diameter is generally of a millimeter level), it takes a long time to print each pass. When a current pass is prepared to be printed, material on a previous pass adjacent to the current pass may have been in or close to a solidification state, and 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 on the previous pass that have been in or close to a solidification state to form an integral part. A process of material fusion between adjacent passes herein is called a pass overlap.

In a process of a pass overlap, if the previous pass of the current pass has already solidified or been close to solidified and the current pass is still in a molten state, a phenomenon of poor fusion may occur in a material fusion process between adjacent passes, which results in a poor mechanical property of a printed article. In addition, since the state of materials is not synchronized, a shape of an object obtained after fusion of materials on adjacent passes is also relatively rough. For example, in a case of printing a cylinder, as shown in <FIG>, a cylinder <NUM> is printed in a pass overlap manner by using a conventional 3D printing technique. The cylinder <NUM> not only has an overall rough shape and contour, but also has a plurality of notches <NUM> due to poor material fusion in a process of pass overlap.

A device <NUM> provided by an embodiment of the present application tracks and prints a cross-sectional contour line of a target printing region by adjusting a length and a position of a discharge port <NUM>. Therefore, in the process of printing the target printing region, the device <NUM> does not need to perform printing on a pass-by-pass basis according to a pass, so that it is not necessary to perform a pass overlap, and no problem of poor fusion occurs. Therefore, an article printed by the device <NUM> has a high mechanical property. As shown in <FIG>, a cylinder <NUM> is printed by a device <NUM>. Compared to the cylinder <NUM>, a filling material of the cylinder <NUM> is in good fusion condition, and there is no problem of poor fusion caused by a pass overlap.

To still take the case of printing a cylinder as an example, referring to <FIG>, in a conventional 3D printing process, a switch between passes is performed according to a fold line <NUM> instead of a real contour curve, that is, a fold line is used to approximate a real contour curve, resulting in that a printed contour line of a cylinder <NUM> is relatively rough. A device <NUM> provided by an embodiment of the present application does not need to perform printing according to a pass, but tracks and prints a cross-sectional contour line of a target printing region by adjusting a length and a position of a discharge port <NUM>. Therefore, a contour line of a cylinder <NUM> printed by the device <NUM> is also smoother and more realistic.

The target printing region may be determined in a variety of manners. For example, whether all of the printing region of a layer to be printed is regarded as a target printing region or divided into a plurality of target printing regions respectively for printing may be determined according to one or more factors of a shape of a cross-sectional contour line of the layer to be printed, a length of the longest intercept line segment, and a size of a discharge port.

For example, when a length of the longest intercept line segment of the cross-sectional contour line of the layer to be printed is less than or equal to the maximum length of the discharge port, all of the printing region of the layer to be printed may be determined as the target printing region; or when a length of the longest intercept line segment of the cross-sectional contour line of the layer to be printed is greater than the maximum length of the discharge port, all of the printing region of the layer to be printed is divided into a plurality of the target printing regions.

As another example, when the cross-sectional contour line of the layer to be printed encompasses a plurality of closed regions that are not in communication, each of the closed regions may be regarded as one or more target printing regions for printing.

As another example, in some embodiments, instead of dividing all of a printing region of the layer to be printed, all of the printing region of the layer to be printed is directly regarded as the target printing region. For example, the device <NUM> may be designed as a special-purpose device that specifically prints a particular article, and the length of the discharge port <NUM> of the device <NUM> is designed to be able to print all of the printing region of each printing layer of the article at once. In this way, in actual operation, the device <NUM> can print each layer of the article in a fixed manner without the need to divide the printing region online.

As shown in <FIG>, the device <NUM> may further include a feeding apparatus <NUM>. The feeding apparatus <NUM> may feed material for the discharge port <NUM> through the feeding pipe <NUM>. The device <NUM> may further include a drive apparatus (not shown in the figure) configured to drive the feeding apparatus <NUM>. Driving of the feeding apparatus by the drive apparatus can enable the amount of the material extrusion of the discharge port <NUM> to match the size of the discharge port.

The feeding apparatus <NUM> may be a screw feeding apparatus as shown in <FIG>, a pneumatic feeding apparatus as shown in <FIG> or a piston feeding apparatus as shown in <FIG>.

In the case that the feeding apparatus <NUM> is a screw feeding apparatus, an amount of material extruded from a discharge port <NUM> may be controlled in such a way that a drive apparatus adjusts a rotation speed of a screw, in the case that the feeding apparatus <NUM> is a pneumatic feeding apparatus, the amount of material extruded from the discharge port <NUM> may be controlled by adjusting a pressure acting on a liquid surface of the material; and in the case that the feeding apparatus <NUM> is a piston feeding apparatus, the amount of material extruded from the discharge port <NUM> may be controlled in such a way that a drive apparatus adjusts a moving speed of a piston in a piston cylinder-shaped feed port.

That the amount of the material extrusion of the discharge port <NUM> matches the length of the discharge port <NUM> means that the amount of the material extrusion of the discharge port <NUM> changes in proportion to the length of the discharge port <NUM>.

During actual printing, the amount of the material extrusion may be determined according to the length of the discharge port <NUM>. Then, the amount of material feeding of the feeding apparatus <NUM> may be controlled so that the material feeding amount is equal to the amount of the material extrusion.

As shown in <FIG>, the device <NUM> may also include a control apparatus <NUM> for controlling the various drive apparatuses mentioned above. The control apparatus <NUM> may be a special-purpose numerical control device or a general-purpose processor. Furthermore, the control apparatus <NUM> may be a distributed control apparatus or a centralized control apparatus.

Hereinafter, description is made to a method embodiment of the present application. Since the method embodiment may be performed by the device <NUM> described above (specifically by the control apparatus <NUM> in the device <NUM>), parts not described in detail may refer to the above text.

A device for 3D printing is also provided by an embodiment of the present application, which has a discharge port with adjustable length, and an extrusion passage of the discharge port is a structure with variable section along material flow direction.

For example, the extrusion passage of the discharge port is a structure in which a section along material flow direction gradually shrinks to a required size of the discharge port. Size of the discharge port may include width and length.

For example, the extrusion passage of the discharge port is a structure in which the section along material flow direction gradually shrinks to a required width of the discharge port. In other words, width of the section of the extrusion passage of the discharge port along material flow direction gradually shrinks to a required width of the discharge port.

According to the invention, the extrusion passage of the discharge port is a structure in which the section along material flow direction gradually shrinks to a required length of the discharge port.

In order to realize that the extrusion passage of the discharge port is a structure in which the section along material flow direction gradually shrinks to a required size of the discharge port, the discharge port may be designed in a variety of ways.

As an example, as shown in <FIG>, the section of the extrusion passage of the discharge port in a length direction may be a stepped flow passage section.

As another example, as shown in <FIG>, the section of the extrusion passage of the discharge port in a length direction may be a streamlined flow passage section.

Optionally, the section of the extrusion passage of the discharge port in a length direction may be designed as other feasible shapes or patterns, as long as it can make the extrusion passage of the discharge port to be a structure in which the section along material flow direction gradually shrinks to a required size of the discharge port.

As yet another example, the section of the extrusion passage of the discharge port in a width direction may also be a stepped flow passage section or a streamlined flow passage section (not shown in the figure).

A 3D printing extrusion material is usually a high viscosity substance, and a resistance produced by the extrusion material is proportional to a passage length of the discharge port. When a width of the discharge port is very small (a relative small width of the discharge port will be required when the printing accuracy is high), the discharge port is equivalent to a slit passage as shown in <FIG>, and the resistance of the extrusion material will be very large, which will reduce the printing efficiency. In this case, a very large extrusion pressure is required to be provided to squeeze the material out of the slit passage at a high speed in order to achieve high precision 3D printing with high efficiency, and the material conveying system is required to provide a very large conveying power, which will significantly raise cost of printing, making the printing process uneconomic.

In the device provided by an embodiment of the present application, the extrusion passage of the discharge port is a structure in which the section along material flow direction gradually shrinks to a required size of the discharge port, which can effectively reduce a resistance of material extrusion, so as to improve the efficiency of printing molding. In addition, since the resistance of material extrusion can be reduced, a requirement on conveying power of the material conveying system can be reduced, so as to reduce printing cost.

An application scenario of this embodiment includes, but is not limited to, the device <NUM> provided in the above embodiments.

For example, the device for 3D printing provided by an embodiment of the present application is the device <NUM> provided in the above embodiments, and the discharge port provided by an embodiment of the present application is the discharge port <NUM> in the device <NUM>.

When the sleeve <NUM> is an integrally formed sleeve, a mold of the sleeve <NUM> may be used to form the discharge port <NUM> in which the section along material flow direction of the extrusion passage gradually shrinks to a required size of the discharge port.

When the sleeve <NUM> includes a plurality of separable portions, a stepped structure may be disposed on abutting faces of adjacent two portions to form the discharge port <NUM> in which the section along material flow direction of the extrusion passage gradually shrinks to a required size of the discharge port.

For example, in the above embodiments shown in <FIG> and <FIG>, the abutting faces between the first portion <NUM> and the second portion <NUM> may have a stepped structure along material outflow direction to make a passage of the discharge port <NUM> be a structure in which a section along material outflow direction gradually shrinks to a required size of the discharge port <NUM>.

For example, in the above embodiments shown in <FIG> and <FIG>, abutting faces between two portions spliced from the first portion <NUM>, the second portion <NUM>, the third portion <NUM> and the fourth portion <NUM> may have a stepped structure along material outflow direction to make a passage of the discharge port <NUM> be a structure in which a section along material outflow direction gradually shrinks to a required size of the discharge port <NUM>.

Taking an embodiment shown in <FIG> as an example, the abutting face <NUM> of the first portion <NUM> may include a stepped structure along material outflow direction as shown in <FIG>, and the abutting face <NUM> may include an upper stepped surface <NUM> and a lower stepped surface <NUM>. The abutting face <NUM> of the second portion <NUM> may also include a stepped structure along material outflow direction (similar to the stepped structure of the abutting face <NUM>, not shown in the figure). In this way, the extrusion passage of the discharge port <NUM> formed by abutting between the first portion <NUM> and the second portion <NUM> is a structure in which the section along material flow direction gradually shrinks to a required size of the discharge port, as shown in <FIG>. In this example, the section of the extrusion passage of the discharge port <NUM> in a length direction is a stepped flow passage section as shown in <FIG>.

The first portion <NUM> and the second portion <NUM> shown in <FIG> are assembled together with the feeding pipe <NUM>, to form the device <NUM> with the discharge port <NUM>, whose extrusion passage has a structure in which the section along material flow direction gradually shrinks to a required width of the discharge port, as shown in <FIG>. In the example shown in <FIG>, cross sections of the feeding pipe <NUM> and the sleeve <NUM> in a direction through the extrusion passage of discharge port <NUM> are shown in <FIG>, and the discharge port <NUM>(<NUM>) shown in <FIG> indicates a discharge port whose extrusion passage is a structure in which the section along material flow direction gradually shrinks to a required size of the discharge port.

<FIG> is a schematic flowchart of a control method provided by an embodiment of the present application. The control method of <FIG> may control a device for 3D printing. The device may for example be the device <NUM> described above, and the control method may for example be performed by the control apparatus <NUM> in the device <NUM>.

The device may include a feeding pipe and a sleeve. An opening extending along an axial direction of the feeding pipe is disposed on an outer wall of the feeding pipe. A sleeve may be sleeved on the feeding pipe, and a discharge port in communication with the opening is disposed on an outer wall of the sleeve. The sleeve may rotate around an axis of the feeding pipe relative to the feeding pipe.

The method of <FIG> may include step S2710 of controlling the sleeve to rotate around the axis of the feeding pipe relative to the feeding pipe, so as to make the discharge port and the opening communicate or no longer communicate.

Optionally, the step S2710 includes: controlling the sleeve to rotate around an axis of the feeding pipe relative to the feeding pipe when printing is required to be suspended, so as to make the discharge port no longer be in communication with the opening to block a material conveying passage.

Optionally, the step S2710 includes: controlling the sleeve to rotate around the axis of the feeding pipe relative to the feeding pipe when printing is required to be started, so as to make the discharge port be in communication with the opening to open a material conveying passage.

According to the invention, the method of <FIG> includes step S2720 of adjusting a size of the discharge port.

According to the invention, the outer wall of the sleeve includes a first portion and a second portion, and the first portion and the second portion are slidable relative to each other along the axial direction. Step S2720 includes:
controlling the relative sliding between the first portion and the second portion for adjusting the size of the discharge port.

Optionally, the first portion includes a first upper stepped surface, a first lower stepped surface and a first connecting surface connecting the first upper stepped surface and the first lower stepped surface, 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 first upper stepped surface and the first lower stepped surface are in contact with the second lower stepped surface and the second upper stepped surface, respectively, and are slidable relative to the second lower stepped surface and the second upper stepped surface along the axial direction, and a hollow area formed by the first lower stepped surface, the first connecting surface, the second lower stepped surface and the second connecting surface is the discharge port.

Optionally, step S2720 may include: adjusting the size of the discharge port such that the length of the discharge port matches lengths of intercept line segments of a cross-sectional contour line of a target printing region of a layer to be printed, where the target printing region is part or all of a printing region of the layer to be printed.

Optionally, step S2720 may include: adjusting the size of the discharge port such that two ends for defining a length of the discharge port are aligned with the cross-sectional contour line of the target printing region in a vertical direction.

Optionally, the method of <FIG> may further include: adjusting a relative position between the feeding pipe and the sleeve as a whole and a printing platform, such that two ends for defining the length of the discharge port are aligned with the cross-sectional contour line of the target printing region in a vertical direction.

Optionally, the method of <FIG> may further include: determining all of the printing region of the layer to be printed as the target printing region when a length of the longest intercept line segment of the cross-sectional contour line of the layer to be printed is less than or equal to the maximum length of the discharge port; or dividing all of the printing region of the layer to be printed into a plurality of the target printing regions when a length of the longest intercept line segment of the cross-sectional contour line of the layer to be printed is greater than the maximum length of the discharge port.

Optionally, the method of <FIG> may further include: controlling a feeding apparatus to feed material for the discharge port such that the amount of the material extrusion of the discharge port matches the size of the discharge port.

Optionally, a plurality of discharge ports are disposed on the outer wall of the sleeve. The method of <FIG> may further include: controlling the sleeve to move relative to the feeding pipe such that the opening is capable of being in communication with different discharge ports.

Optionally, the plurality of the discharge ports are arranged along a circumferential direction of the sleeve, and the controlling the sleeve to move relative to the feeding pipe such that the opening is capable of being in communication with different discharge ports may include: controlling the sleeve to be rotatable around an axis of the feeding pipe such that the opening is capable of being in communication with different discharge ports.

Optionally, the widths of different discharge ports are different.

The above embodiments may completely or partly be implemented in software, hardware, firmware or a random combination thereof. When implemented by software, they may completely or partly be implemented in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the processes or functions described according to the embodiments of the present application are completely or partly generated. The computer may be a general-purpose computer, a special-purpose computer, a computer network or other programmable apparatus. The computer instructions may be stored in a computer-readable storage medium or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions may be transmitted from a web site, a computer, a server or a data center to another web site, computer, server or data center in a wired mode (for example, a coaxial cable, an optical fiber, a digital subscriber line (DSL)) or a wireless mode (for example, infrared, radio, microwave or the like). The computer-readable storage medium may be any available medium capable of being accessed by a computer or a data storage device including a server, a data center or the like integrated by one or more available media. The available medium may be a magnetic medium (for example, a soft disk, a hard disk, a magnetic tape), an optical medium (for example, a digital video disc (DVD)), or a semiconductor medium (for example, a solid state disk (SSD)) or the like.

Those of ordinary skill in the art may be aware that, units and algorithm steps of the examples described in the embodiments disclosed in the text can be implemented by electronic hardware, or a combination of computer software and electronic hardware. Whether these functions are performed by hardware or software depends on particular applications and designed constraint conditions of the technical solutions. Persons skilled in the art may use different methods to implement the described functions for every particular application, but it should not be considered that such implementation goes beyond 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 manners. The indirect couplings or communication connections between the apparatuses or units may be implemented in electrical, mechanical, or other forms.

The units described as separate components may or may not be physically separate, and components displayed as units may or may not be physical units, may be located in one position, or may be distributed on multiple network units.

The foregoing descriptions are merely specific embodiments of the present application, but the protection scope of the present application is not limited thereto.

Claim 1:
A device for 3D printing, comprising:
a feeding pipe (<NUM>), wherein an opening (<NUM>) extending along an axial direction of the feeding pipe (<NUM>) is disposed on an outer wall of the feeding pipe (<NUM>); and
a sleeve (<NUM>) sleeved on the feeding pipe (<NUM>), wherein a discharge port (<NUM>) in communication with the opening (<NUM>) is disposed on an outer wall of the sleeve (<NUM>), the sleeve (<NUM>) is capable of rotating around an axis of the feeding pipe (<NUM>) relative to the feeding pipe (<NUM>), so as to make the discharge port (<NUM>) and the opening (<NUM>) communicate or no longer communicate;
a passage of the discharge port (<NUM>) is a structure in which a section along material outflow direction gradually shrinks to a required size of the discharge port (<NUM>), the discharge port (<NUM>) is a discharge port with a continuously adjustable size, and the discharge port (<NUM>) being suitable for performing a continuous printing along a cross-sectional contour line of a target printing region; and
the outer wall of the sleeve (<NUM>) comprises a first portion (<NUM>) and a second portion (<NUM>), the first portion (<NUM>) and the second portion (<NUM>) are slidable relative to each other along the axial direction to adjust the length of the discharge port (<NUM>).