CN113681882A - 3D printing method and 3D printer - Google Patents

Abstract

The invention discloses a 3D printing method and a 3D printer, and relates to the technical field of 3D printing. The 3D printing method includes the following steps: determining current printing data according to a printing model, where the current printing data includes the current printing unit at the current printing position At least one of the thickness and width of the 3D printer; determine the control parameters of the 3D printer according to the current printing data, the control parameters include the target moving speed of the nozzle of the 3D printer, the target printing height of the nozzle and the at least one of the target wire feeding speed of the nozzle; controlling the 3D printer to print the current printing unit according to the control parameter. The invention solves the problem of the step effect in the existing 3D printing method, realizes the real-time adaptive regulation of the cross-sectional shape and size of the fuse wire, reduces the surface roughness of the workpiece, and improves the surface geometric quality of the workpiece.

Description

3D printing method and 3D printer

technical field

The invention relates to the technical field of 3D printing, in particular to a 3D printing method and a 3D printer.

Background technique

At present, 3D printing, also known as the additive manufacturing of material extrusion (ME), is to heat and melt the constant diameter wire passing through the nozzle through a nozzle with a constant diameter to form a fixed cross-sectional shape and size. The fuses are stacked on the surface of the part, accumulated layer by layer, and finally form the three-dimensional shape of the part (as shown in Figure 1). The irregular parts manufactured by this method have obvious step effects on the inclined surface, which seriously affects the dimensional accuracy and Surface roughness. In order to overcome the above shortcomings, relevant researchers at home and abroad have successively proposed the curved layer fused deposition modeling (CLFDM) process method and the conformal surface layering algorithm (as shown in Figure 2), which can effectively avoid the step effect, No supports are required, the number of layers is reduced (increased efficiency), and the mechanical properties of the part are improved.

However, during the fused deposition molding of curved surface slices, a filament with a constant diameter passing through the nozzle is also heated and melted through a nozzle with a constant diameter to form a fuse with a fixed cross-sectional shape and size. For plate and shell parts with uneven thickness, the thickness of the fuse cannot be adaptively adjusted by using the equal-thickness surface slicing layer, and the step effect cannot be avoided (as shown in Figure 3). For parts, the width of the fuse cannot be adaptively adjusted by using the equal-thickness curved surface layer, so the step effect of the part in the width direction cannot be eliminated, and there will still be steps at the edge (as shown in Figure 4).

Therefore, for parts with uneven thickness or width, it is still difficult to give full play to the advantages of surface slicing by using equal-thickness surface slicing, which destroys the surface structure of the part and reduces the static strength and fatigue resistance of the part.

SUMMARY OF THE INVENTION

By providing a method, the present invention solves the problem of step effect in the existing 3D printing method, realizes real-time adaptive regulation of the cross-sectional shape and size of the fuse wire, maintains the complete surface structure of the workpiece, and reduces the cost of the workpiece. Surface roughness, improve the surface geometric quality of the workpiece, and ensure that the workpiece has good mechanical properties.

In order to achieve the above purpose, the present invention provides a 3D printing method, which is applied to a 3D printer, and the 3D printing method includes the following steps:

Determine current print data according to the print model, the current print data including at least one of the thickness and width of the current print unit at the current print position;

A control parameter of the 3D printer is determined according to the current printing data, and the control parameter includes at least a target moving speed of the nozzle of the 3D printer, a target printing height of the nozzle, and a target wire feeding speed of the nozzle. One;

The 3D printer is controlled to print the current printing unit according to the control parameter.

Further, the step of determining the control parameters of the 3D printer according to the current printing data includes:

When the current printing data includes the thickness of the current printing unit, the thickness of the current printing unit is used as the target printing height of the nozzle.

Further, the step of determining the control parameters of the 3D printer according to the current printing data includes:

When the current printing data includes the width of the current printing unit, acquiring the diameter of the printing wire and the preset wire feeding speed;

The target moving speed of the nozzle is determined according to the current printing data, the diameter of the printing filament and the preset filament feeding speed.

Further, after the step of determining the target moving speed of the nozzle according to the current printing data, the diameter of the printing filament and the preset filament feeding speed, the method further includes:

When the target moving speed of the nozzle is greater than or equal to a first moving speed threshold, the first moving speed threshold is used to update the target moving speed of the nozzle;

The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the first moving speed threshold.

Further, after the step of determining the target moving speed of the nozzle according to the current printing data, the diameter of the printing filament and the preset filament feeding speed, the method further includes:

When the target moving speed of the nozzle is less than or equal to a second moving speed threshold, the second moving speed threshold is used to update the target moving speed of the nozzle, wherein the second moving speed threshold is less than the first moving speed speed threshold;

The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the second moving speed threshold.

Further, after the step of determining the target wire feeding speed of the nozzle according to the current printing data, the diameter of the printing wire and the first moving speed threshold, the method further includes:

When the target wire feeding speed of the nozzle is greater than or equal to the wire feeding speed threshold value, the target wire feeding speed of the nozzle is updated by using the wire feeding speed threshold value.

Further, the step of determining the control parameters of the 3D printer according to the current printing data includes:

Determine whether the current print data is consistent with the previous print data;

When the current printing data is inconsistent with the previous printing data, the control parameters of the 3D printer are re-determined according to the current printing data.

Further, when the thickness of the current printing unit is smaller than the thickness of the previous printing unit, the target printing height of the nozzle is smaller than the printing height of the nozzle when printing by the previous printing unit; and/or,

When the width of the current printing unit is smaller than the width of the previous printing unit, the target moving speed of the nozzle is greater than the moving speed of the nozzle when the previous printing unit is printing, or the target feeding of the nozzle is The speed is lower than the feeding speed of the nozzle when the previous printing unit is printing.

Further, before the step of determining the control parameters of the 3D printer according to the current printing data, it also includes:

When the current printing data includes the width of the current printing unit, acquiring the outer diameter of the nozzle of the 3D printer;

When the width of the current printing unit is greater than or equal to the outer diameter of the nozzle, the outer diameter of the nozzle is used as the width of the current printing unit.

In order to achieve the above object, the present invention also provides a 3D printer, the 3D printer includes a memory, a processor and a computer program stored in the memory and running on the processor, the computer program being processed by the processor The steps of the 3D printing method as described above are realized when the device is executed.

In order to achieve the above object, the present invention also provides a storage medium on which a control program of a 3D printer is stored, and when the control program of the 3D printer is executed by a processor, the steps of the 3D printing method described above are implemented.

One or more technical solutions provided in the present invention have at least the following technical effects or advantages:

In the technical solution of the present invention, the control parameters of the 3D printer, including the target moving speed of the nozzle, the target printing height of the nozzle and the target wire feeding speed of the nozzle, are determined according to the printing data, that is, according to the thickness of the printing unit Even if there is a changed layer thickness or a changed path width in the printed model, the control parameters of the 3D printer are matched to it. In this way, when the 3D printer runs according to the control parameters determined by the above method , which can adjust the cross-sectional shape and size (thickness and width) of the fuse in real time during the extrusion process of the fuse, so as to maintain a complete wire structure without steps in the thickness and width directions, so that the printed The shape of the part can well conform to the preset printing model, effectively overcoming the "step effect" on the outer surface of the part due to changing layer thickness or changing path width, so as to maintain the complete surface structure of the part and reduce manufacturing costs. It can improve the surface roughness of the parts, improve the surface geometric quality of the parts, and ensure that the parts have good static strength and fatigue resistance.

Description of drawings

Fig. 1 is the plane slice printing schematic diagram of the prior art;

2 is a schematic diagram of the prior art curved surface slice printing;

3 is a schematic diagram of steps in the height direction during the prior art curved surface slice printing;

4 is a schematic diagram of steps in the width direction during the prior art curved surface slice printing;

FIG. 5 is a schematic diagram of the state when the 3D printer uses the 3D printing method of the present invention to print;

Figure 6 is a schematic cross-sectional view at A-A in Figure 5;

7 is a schematic diagram of a terminal structure of a hardware operating environment involved in an embodiment of the present invention;

FIG. 8 is a schematic flowchart of the first embodiment of the 3D printing method of the present invention;

9 is a schematic flowchart of a second embodiment of the 3D printing method of the present invention;

FIG. 10 is a schematic diagram of the refinement process of step S200 in the third embodiment of the 3D printing method of the present invention;

FIG. 11 is a schematic flowchart of the refinement of step S200 in the fourth embodiment of the 3D printing method of the present invention;

FIG. 12 is a schematic flowchart of the refinement of step S200 in the fifth embodiment of the 3D printing method of the present invention;

13 is a schematic flowchart of the sixth embodiment of the 3D printing method of the present invention;

FIG. 14 is a schematic flowchart of the refinement of step S200 in the seventh embodiment of the 3D printing method of the present invention;

FIG. 15 is a schematic flowchart of the tenth embodiment of the 3D printing method of the present invention.

Detailed ways

For better understanding of the above technical solutions, exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While exemplary embodiments of the present disclosure are shown in the drawings, it should be understood that the present disclosure may be embodied in various forms and should not be limited by the embodiments set forth herein. Rather, these embodiments are provided so that the present disclosure will be more thoroughly understood, and will fully convey the scope of the present disclosure to those skilled in the art.

In order to better understand the above technical solutions, the above technical solutions will be described in detail below with reference to the accompanying drawings and specific embodiments.

As shown in FIG. 7 , FIG. 7 is a schematic diagram of a terminal structure of a hardware operating environment involved in an embodiment of the present invention.

The terminal in the embodiment of the present invention may be a 3D printer, or may be a PC, an industrial computer, or other equipment.

As shown in FIG. 7 , the terminal may include: a processor 1001 , such as a CPU, a network interface 1004 , a user interface 1003 , a memory 1005 , and a communication bus 1002 . Among them, the communication bus 1002 is used to realize the connection and communication between these components. The user interface 1003 may include a display screen (Display), an input unit such as a keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface and a wireless interface. Optionally, the network interface 1004 may include a standard wired interface and a wireless interface (eg, a WI-FI interface). The memory 1005 may be high-speed RAM memory, or may be non-volatile memory, such as disk memory. Optionally, the memory 1005 may also be a storage device independent of the aforementioned processor 1001 .

Those skilled in the art can understand that the structure of the 3D printer shown in FIG. 7 does not constitute a limitation on the 3D printer, and may include more or less components than the one shown, or combine some components, or arrange different components. For example, the structure of the 3D printer can also include a worktable, a five-axis (or three-axis) drive module, a wire feed motor, a nozzle, an electric heating wire, etc. The five-axis drive module is installed on the worktable, and the nozzle is installed on the five-axis The driving end of the drive module; the nozzle is provided with a wire inlet and a wire outlet that communicate with the inner cavity of the nozzle, and the wire inlet is provided with a wire feeding roller, and the wire feeding motor is connected to the wire feeding roller; the electric heating wire is installed on the nozzle of the inner cavity sidewall. The five-axis drive module, the wire feed motor, and the electric heating wire are respectively electrically connected to the processor 1001. The processor 1001 controls the five-axis drive module, the wire feed motor, and the electric heating wire to work according to the instructions, and controls the five-axis drive according to the instructions. The module drives the nozzle to move in the five-axis coordinate system (three linear coordinates and two rotary coordinates), so that the nozzle moves according to the preset material filling trajectory, or controls the wire feeding motor to drive the wire feeding roller to rotate according to the command to drive the wire. The raw material (thermoplastic material) enters the inner cavity of the nozzle from the wire inlet of the nozzle, or the electric heating wire is energized according to the command to make the electric heating wire heat up, so that the wire entering the inner cavity of the nozzle from the nozzle wire inlet is heated and melted Then, it is extruded from the filament outlet of the nozzle, and the extruded material is bonded with the solidified material and stacked layer by layer to complete the printing of the entire printing model.

As shown in FIG. 7 , the memory 1005 as a storage medium may include an operating system, a network communication module, a user interface module, and a control application program of the 3D printer.

In the terminal shown in FIG. 7 , the network interface 1004 is mainly used to connect to the background server and perform data communication with the background server; the user interface 1003 is mainly used to connect to the client (client) and perform data communication with the client; and the processor 1001 can be used to invoke the control application of the 3D printer stored in memory 1005 and perform the following operations:

Determine current print data according to the print model, the current print data including at least one of the thickness and width of the current print unit at the current print position;

A control parameter of the 3D printer is determined according to the current printing data, and the control parameter includes at least a target moving speed of the nozzle of the 3D printer, a target printing height of the nozzle, and a target wire feeding speed of the nozzle. One;

The 3D printer is controlled to print the current printing unit according to the control parameter.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the current printing data includes the thickness of the current printing unit, the thickness of the current printing unit is used as the target printing height of the nozzle.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the current printing data includes the width of the current printing unit, acquiring the diameter of the printing wire and the preset wire feeding speed;

The target moving speed of the nozzle is determined according to the current printing data, the diameter of the printing filament and the preset filament feeding speed.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the target moving speed of the nozzle is greater than or equal to a first moving speed threshold, the first moving speed threshold is used to update the target moving speed of the nozzle;

The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the first moving speed threshold.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the target moving speed of the nozzle is less than or equal to a second moving speed threshold, the second moving speed threshold is used to update the target moving speed of the nozzle, wherein the second moving speed threshold is less than the first moving speed speed threshold;

The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the second moving speed threshold.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the target wire feeding speed of the nozzle is greater than the wire feeding speed threshold value, the target wire feeding speed of the nozzle is updated by using the wire feeding speed threshold value.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

Determine whether the current print data is consistent with the previous print data;

When the current printing data is inconsistent with the previous printing data, the control parameters of the 3D printer are re-determined according to the current printing data.

Further, when the thickness of the current printing unit is smaller than the thickness of the previous printing unit, the target printing height of the nozzle is smaller than the printing height of the nozzle when printing by the previous printing unit; and/or,

When the width of the current printing unit is greater than the width of the previous printing unit, the target moving speed of the nozzle is lower than the moving speed of the nozzle when the previous printing unit is printing, or the target feeding of the nozzle is The speed is greater than the feeding speed of the nozzle when the previous printing unit is printing.

Further, the processor 1001 can call the control application program of the 3D printer stored in the memory 1005, and also perform the following operations:

When the current printing data includes the width of the current printing unit, acquiring the outer diameter of the nozzle of the 3D printer;

When the width of the current printing unit is greater than or equal to the outer diameter of the nozzle, the outer diameter of the nozzle is used as the width of the current printing unit.

The main solutions of the embodiments of the present invention are: determine current printing data according to a printing model, the current printing data includes at least one of the thickness and width of the current printing unit at the current printing position; determine the current printing data according to the current printing data Control parameters of the 3D printer, the control parameters include at least one of the target moving speed of the nozzle of the 3D printer, the target printing height of the nozzle, and the target wire feeding speed of the nozzle; The control parameter prints the current printing unit.

In the prior art, 3D printing is to use a nozzle with a constant diameter to heat and melt a wire with a constant diameter passing through the nozzle to form a fuse with a fixed cross-sectional shape and size, which is deposited on the surface of the part, accumulated layer by layer, and finally formed. 3D shape of the part. For parts with uneven thickness or width, there is an obvious step effect on the inclined surface, which seriously affects the dimensional accuracy and surface roughness of the part, destroys the surface structure of the part, and reduces the static strength and fatigue resistance of the part.

The present invention provides a solution. In the 3D printing method of the present invention, the control parameters of the 3D printer, including the target moving speed of the nozzle, the target printing height of the nozzle and the target wire feeding speed of the nozzle, are based on the printing The data is determined, that is, it is determined according to the thickness and width of the printing unit. Even if there is a changing layer thickness or changing path width in the printing model, the control parameters of the 3D printer are matched to it. When the printer operates according to the control parameters determined by the above method, it can adjust the cross-sectional shape and size (thickness and width) of the fuse in real time during the extrusion process of the fuse, so as to keep the thickness and width direction free. The complete wire structure of the step makes the shape of the printed part well conform to the preset printing model, and effectively overcomes the "step effect" on the outer surface of the whole part caused by the changing layer thickness or changing path width. Maintain the complete surface structure of the workpiece, reduce the surface roughness of the workpiece, improve the surface geometric quality of the workpiece, and ensure that the workpiece has good static strength and fatigue resistance.

The present invention provides a first embodiment of a 3D printing method, please refer to FIG. 8 , in the first embodiment of the present invention, the 3D printing method includes the following steps:

S100. Determine current print data according to the print model, where the current print data includes at least one of the thickness and width of the current print unit at the current print position;

Specifically, 3D printer printing mainly uses layered processing to print and form. Before printing, the printing model needs to be preprocessed, that is, each printing slice of the printing model and the printing path of each layer are obtained by analyzing and calculating the printing model. Further, the variable-thickness layering algorithm can be used to obtain the unequal-thickness slice results of the printing model, and the variable-width path planning algorithm can be used to obtain the variable-width path of each layer. Among them, compared with plane slice printing, surface slice printing can avoid the step effect to a certain extent, no need for support, reduce the number of layers (improve efficiency), and improve the mechanical properties of the part, so curved slice printing can be preferred. Print.

According to the printing progress per unit time, each printing slice can be divided into multiple printing units connected in sequence along each printing path. If the above unit time is limited to a time point, the state of real-time control can be achieved. The printing unit at the current printing position is the current printing unit, the printing unit at the previous printing position is the previous printing unit, and so on. It is easy to understand that the current printing position and the previous printing position are relative in time, and are continuously advancing. After the printing of the current printing unit is completed, the current printing position becomes the previous printing position, and the next printing position. It becomes the current print position. For the sake of clarity, the following descriptions are made from the perspective of the current printing time point. By printing the current printing unit in real time at the current printing position, after accumulating the total printing time, the entire 3D model can be printed.

The thickness and width of the printing unit refer to the thickness and width of the cross section of the printing unit (equivalent to the fuse) at the same printing position. The thicknesses of the printing units at different printing positions may be the same or different, and similarly, the widths of the printing units at different printing positions may be the same or different, which are not limited in the present invention. It can be understood that determining the current print data according to the print model here refers to determining the changed data in the current print data. If the data does not change, it has been acquired before, and there is no need to repeat the determination, so it includes three cases: if the current print If only the thickness of the unit changes, you need to re-determine the thickness of the current printing unit; if only the width of the current printing unit changes, you need to re-determine the width of the current printing unit; if the thickness and width of the current printing unit change at the same time, you need to re- Determines the thickness and width of the current print unit.

S200. Determine the control parameters of the 3D printer according to the current printing data, where the control parameters include the target moving speed of the nozzle of the 3D printer, the target printing height of the nozzle, and the target wire feeding speed of the nozzle at least one of;

It can be understood that the target moving speed of the nozzle, the target printing height of the nozzle and the target wire feeding speed of the nozzle are all for the current printing position. Wherein, according to the current printing data of the current printing position (including the thickness and/or width of the current printing unit), at least one of the target moving speed of the nozzle, the target printing height of the nozzle, and the target wire feeding speed of the nozzle can be determined. It can be understood that determining the control parameters of the 3D printer according to the current printing data here refers to determining the parameters that change in the control parameters. If the parameters remain unchanged, the operation can be performed according to the previous parameters, and there is no need to repeat the determination, so the control parameters are determined. The method can be to determine any one of the target moving speed of the nozzle, the target printing height of the nozzle, and the target wire feeding speed of the nozzle, a combination of any two, or a combination of any three. After the control parameters of the 3D printer are determined, the 3D printer is controlled to run according to the set control parameters to complete the printing of the planned printing data. It can be understood that when the control parameters determined in the above scheme are operated, that is, when the current position is printed according to the determined target moving speed of the nozzle, the target printing height of the nozzle and the target wire feeding speed of the nozzle, the current position of the fuse formed at the current position is the same. The section shape is consistent with the current print data (thickness and width of the current print unit). Among them, the moving speed of the nozzle and the printing height of the nozzle are controlled by the five-axis drive module, and the feeding speed of the nozzle is controlled by the feeding motor. During the printing process, the five-axis drive module should control the nozzles to be always perpendicular to the printing surface, so as to ensure that there will be no interference between the nozzles and the printing surface during the printing process.

S300. Control the 3D printer to print the current printing unit according to the control parameter.

Since the control parameters of the 3D printer are determined according to the printing data, that is, according to the thickness and width of the printing unit, even if there are changing layer thicknesses or changing path widths in the printing model, the control parameters of the 3D printer are the same as In this way, when the 3D printer operates according to the control parameters determined by the above method, it can adjust the cross-sectional shape and size (thickness and width) of the fuse wire in real time during the fuse extrusion forming process. In this way, the complete wire structure without steps is maintained in both thickness and width directions, so that the shape of the printed part can well conform to the preset printing model, and effectively overcome the overall loss of the part due to changing layer thickness or changing path width. The "step effect" of the outer surface maintains the complete surface structure of the workpiece, reduces the surface roughness of the workpiece, improves the surface geometric quality of the workpiece, and ensures that the workpiece has good static strength and fatigue resistance.

Further, based on the first embodiment, a second embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 9 . In the second embodiment of the present invention, the step S200 includes:

S210. When the current printing data includes the thickness of the current printing unit, use the thickness of the current printing unit as the target printing height of the nozzle.

According to the volume of the incoming wire material equal to the volume of the outgoing wire material, the following formula can be obtained:

w×h×v=(πd ² )f/4; where,

w is the instantaneous fuse section width (mm);

h is the instantaneous fuse section height (mm);

v is the moving speed of the instantaneous nozzle (mm/s);

d is the diameter of the printing wire (mm);

f is the instantaneous wire feeding speed (mm/s).

Please refer to Figures 5 to 6. Figures 5 and 6 are schematic diagrams showing the state of the 3D printer when printing using the 3D printing method of the present invention. In Figure 5, the nozzle 10 moves in the horizontal direction a, and in Figure 6, the nozzle 10 moves in the horizontal direction. b moves, and the direction b and the direction a are perpendicular. When the 3D printer is printing, the printing filament 21 enters the nozzle 10 from above, and is heated by the nozzle 10 to form a fuse 22 in the nozzle 10. After cooling, it solidifies to form condensed filaments 23 .

In this embodiment, the layer thickness variation at different printing positions can be realized by means of nozzle extrusion. When printing, the instantaneous printing height between the nozzle and the printing surface (that is, the formed surface of the part) should be equal to the instantaneous layer thickness of the printing unit, that is, equal to the instantaneous height of the section of the extruded part of the fuse, that is, by controlling the nozzle height to control the thickness of the layer, and the height of the nozzle is controlled by a five-axis drive module.

Combining the above formula, it can be understood that the moving speed of the nozzle and the feeding speed of the printing filament should be comprehensively considered to ensure that the instantaneous height of the section of the extruded part of the fuse can reach the instantaneous layer thickness of the printing unit. Specifically, if the thickness of the printing unit increases, the target printing height of the nozzle also increases. At this time, under the condition that the width of the printing unit is fixed, the moving speed of the nozzle can be appropriately reduced and/or the printing filament can be increased. The filament feeding speed of the material ensures that the fuse can fill the gap between the nozzle and the printing surface; on the contrary, if the thickness of the printing unit becomes smaller, the target printing height of the nozzle also becomes smaller, and the width of the printing unit is fixed. In this case, appropriately increase the moving speed of the nozzle and/or decrease the feeding speed of the printing filament. In this way, the cross-sectional height of the fuse can be adaptively adjusted according to the thickness of the printing unit, thereby adapting to different thicknesses of the printing unit.

Therefore, when the 3D printer prints according to the target printing height of the nozzle determined by the thickness of the current printing unit, the section height of the fuse can be controlled in real time, so that the section height of the formed fuse is consistent with the thickness of the printing unit in the printing data. Matching, so as to eliminate the step effect of the workpiece in the height direction, maintain the complete surface structure of the workpiece, reduce the surface roughness of the workpiece, improve the surface geometric quality of the workpiece, and ensure that the workpiece has good mechanical properties.

Further, based on the first or second embodiment, a third embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 10 . In the third embodiment of the present invention, the step S200 includes:

S211, when the current printing data includes the width of the current printing unit, obtain the diameter of the printing wire and the preset wire feeding speed;

S212. Determine a target moving speed of the nozzle according to the current printing data, the diameter of the printing filament, and the preset filament feeding speed.

In this embodiment, as shown in Figures 5 and 6, on the premise that the current printing height of the nozzle is determined, the instantaneous overflow of the fuse during the movement of the nozzle determines the width of the point. When the instantaneous overflow of the fuse When it is greater than zero, the fuse overflows from the inner diameter of the nozzle to the outer diameter of the nozzle, and the width of the fuse can be adjusted by changing the amount of overflow. Among them, by adjusting the moving speed of the nozzle and the feeding speed of the printing filament, the instantaneous overflow of the fuse can be adjusted. Specifically, if the width of the printing unit becomes larger, and the thickness of the printing unit is fixed (that is, the target printing height of the nozzle is fixed), the moving speed of the nozzle should be appropriately reduced and/or the printing filament should be increased. On the contrary, if the width of the printing unit becomes smaller and the thickness of the printing unit is fixed (that is, the target printing height of the nozzle is fixed), the moving speed of the nozzle should be appropriately increased and/or reduced. Filament feed speed for small printing filaments. In this way, by adjusting the overflow amount of the fuse between the inner diameter and the outer diameter of the nozzle, the cross-sectional width of the fuse can be adaptively adjusted according to the width of the printing unit, thereby adapting to different widths of the printing unit. Of course, if the width and height of the printing unit change at the same time, it is necessary to comprehensively consider the above formula to determine the appropriate moving speed of the nozzle and the feeding speed of the printing filament.

As an embodiment, according to the performance and actual needs of the equipment, a fixed value can be given to the wire feeding speed of the printing wire in advance, that is, the preset wire feeding speed is given. During the printing process, only by adjusting the movement of the nozzle speed to achieve real-time change control of the height and width of the fuse section. Understandably, according to the above formula; w×h×v=(πd ² )f/4, the thickness of the current printing unit is equal to the instantaneous fuse section height, and the current printing unit width is equal to the instantaneous fuse section width, and because The diameter of the printing filament has been determined when the material is selected. Therefore, when the preset filament feeding speed is determined, the target moving speed of the nozzle can be determined according to the above formula. In this way, when the 3D printer prints according to the target printing height of the nozzle, the preset wire feeding speed and the target moving speed of the nozzle determined by the above method, the cross-sectional shape and size of the fuse can be controlled in real time, so that the cross-section of the formed fuse can be controlled in real time. The height and width of the section match the thickness and width of the printing unit in the printing data, so as to eliminate the step effect of the workpiece in the height and width directions, maintain the complete surface structure of the workpiece, reduce the surface roughness of the workpiece, and improve the workpiece. The geometric quality of the surface ensures that the parts have good mechanical properties.

Further, based on the third embodiment, a fourth embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 11 . In the fourth embodiment of the present invention, after the step S212, the method further includes:

S213. When the target moving speed of the nozzle is greater than or equal to a first moving speed threshold, update the target moving speed of the nozzle using the first moving speed threshold;

S214. Determine a target wire feeding speed of the nozzle according to the current printing data, the diameter of the printing wire, and the first moving speed threshold.

In this embodiment, considering the actual situation, the moving speed of the nozzle is limited to a certain extent, because the five-axis drive module (including the motor and some mechanical parts that requires a certain movement) drives the nozzle to move, and has a certain mass (inertia) , the adjustment range of the moving speed of the nozzle is limited, then, when the moving speed of the nozzle is adjusted to the limit value, the wire feeding speed of the nozzle can be adjusted appropriately (adjust the frequency of the wire feeding motor) to make up for the limited adjustment range of the nozzle moving speed. The determination of the target wire feeding speed of the nozzle can also be calculated with reference to the above formula, that is, the limit value of the moving speed of the nozzle is used as the determined value, and the target wire feeding speed of the nozzle is reversely calculated. It is worth noting that, in general, when controlling the printer to print, the wire feeding speed of the nozzle can remain unchanged, that is, it is controlled according to the preset wire feeding speed, and the cross-sectional size of the wire is adjusted by adjusting the moving speed of the nozzle. , which is conducive to maintaining the uniform melting of the wire, so as to improve the forming quality of the product.

Further, based on the fourth embodiment, a fifth embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 12. In the fifth embodiment of the present invention, after the step S212, the method further includes:

S215. When the target moving speed of the nozzle is less than or equal to a second moving speed threshold, use the second moving speed threshold to update the target moving speed of the nozzle, where the second moving speed threshold is smaller than the first moving speed threshold a moving speed threshold;

S216: Determine a target wire feeding speed of the nozzle according to the current printing data, the diameter of the printing wire, and the second moving speed threshold.

In this embodiment, since the adjustment range of the nozzle moving speed is limited, including the upper limit value (ie the first moving speed threshold) and the lower limit (ie the second moving speed threshold), when determining the target moving speed of the nozzle, it is necessary to Compare the calculated moving speed of the nozzle with the first moving speed threshold and the second moving speed threshold. When the calculated moving speed of the nozzle reaches the first moving speed threshold or the second moving speed threshold, use the first moving speed threshold or the second moving speed threshold. The second moving speed threshold is determined as the target moving speed of the nozzle, and then the cross-sectional shape and size of the fuse is compensated and adjusted by adjusting the wire feeding speed of the nozzle. In this way, the adjustable range of the width of the fuse section can be expanded, thereby helping to expand the applicable range of the 3D printer.

Further, based on the fourth embodiment, a sixth embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 13 . In the sixth embodiment of the present invention, after the step S214, the method further includes:

S217. When the target wire feeding speed of the nozzle is greater than or equal to the wire feeding speed threshold, update the target wire feeding speed of the nozzle by using the wire feeding speed threshold.

In this embodiment, considering that the wire feeding speed of the nozzle is also limited to a certain extent, because the wire feeding speed is too fast, the wire material may not be melted (the electric heating wire has a power limit), so the wire feeding speed of the nozzle can only be adjustment within a certain range. Therefore, when determining the target wire feeding speed of the nozzle, when the calculated wire feeding speed of the nozzle reaches the limit value (that is, the wire feeding speed threshold), the wire feeding speed threshold is used to determine the target wire feeding speed of the nozzle to control the 3D printer. Operation to ensure that the wire is fully melted and avoid the instability of the part structure.

Further, based on the first embodiment, a seventh embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 14 . In the seventh embodiment of the present invention, the step S200 includes:

S220, determine whether the current print data is consistent with the previous print data;

S221. When the current printing data is inconsistent with the previous printing data, re-determine the control parameters of the 3D printer according to the current printing data.

In this embodiment, when the control parameters of the 3D printer are determined according to the current printing data, it is possible to compare whether the current printing data is the same as the previous printing data: when the current printing data is consistent with the previous printing data, it indicates that the cross section of the fuse The height and width do not change, so the control parameters determined according to the previous print data can be directly used without adjusting the control parameters, which can reduce the amount of calculation and improve the calculation efficiency; and when the current print data is inconsistent with the previous print data, then It is necessary to re-determine the control parameters of the 3D printer according to the current printing data to control the cross-sectional height and width of the fuse in real time, eliminate the step effect in the height and width directions of the part, and maintain the complete surface structure of the part.

Further, based on the seventh embodiment, an eighth embodiment of the 3D printing method of the present invention is provided. In the eighth embodiment of the present invention, when the thickness of the current printing unit is smaller than the thickness of the previous printing unit, the nozzle The target printing height of is smaller than the printing height of the nozzle when the previous printing unit is printing.

In this embodiment, the layer thickness variation at different printing positions can be realized by means of nozzle extrusion. When printing, the instantaneous printing height between the nozzle and the printing surface (that is, the formed surface of the part) should be equal to the instantaneous layer thickness of the printing unit, that is, equal to the instantaneous height of the section of the extruded part of the fuse, that is, by controlling the nozzle height to control the layer thickness. Specifically, when the thickness of the current printing unit is equal to the thickness of the previous printing unit, the printing height of the nozzles determined by the previous printing unit is directly used without adjustment; when the thickness of the current printing unit is smaller than the thickness of the previous printing unit, it is necessary to Adjust the printing height of the nozzle to increase; when the thickness of the current printing unit is greater than the thickness of the previous printing unit, the printing height of the nozzle needs to be adjusted to decrease. In this way, the cross-sectional height of the formed fuse can be matched with the thickness of the printing unit in the printing data, thereby eliminating the step effect of the part in the height direction, maintaining the complete surface structure of the part, and reducing the surface roughness of the part. Improve the surface geometric quality of the parts and ensure that the parts have good mechanical properties.

Further, based on the seventh embodiment, a ninth embodiment of the 3D printing method of the present invention is provided. In the ninth embodiment of the present invention, when the width of the current printing unit is smaller than the width of the previous printing unit, the The target moving speed of the nozzle is greater than the moving speed of the nozzle when the previous printing unit is printing, or the target feeding speed of the nozzle is lower than the feeding speed of the nozzle when the previous printing unit is printing.

In this embodiment, the width of the fuse section can be adjusted by adjusting the target moving speed of the nozzle or the target wire feeding speed of the nozzle. Specifically, on the premise that the printing height of the nozzle is determined, when the width of the current printing unit is equal to the width of the previous printing unit, the moving speed of the nozzle determined by the previous printing unit is directly used without adjustment; When the width of the current printing unit is greater than the width of the previous printing unit, the moving speed of the nozzle needs to be adjusted to decrease; when the width of the current printing unit is smaller than the width of the previous printing unit, the moving speed of the nozzle needs to be adjusted to increase. Alternatively, when the width of the current printing unit is equal to the width of the previous printing unit, the wire feeding speed of the nozzle determined by the previous printing unit is directly used without adjustment; when the width of the current printing unit is greater than the width of the previous printing unit When the width of the nozzle needs to be adjusted to increase, the feeding speed of the nozzle needs to be adjusted to decrease when the width of the current printing unit is smaller than the width of the previous printing unit.

Further, based on the first to ninth embodiments, a tenth embodiment of the 3D printing method of the present invention is provided. Please refer to FIG. 15 . In the tenth embodiment of the present invention, before step S200, the method further includes: :

S400, when the current printing data includes the width of the current printing unit, obtain the outer diameter of the nozzle of the 3D printer;

S410. When the width of the current printing unit is greater than or equal to the outer diameter of the nozzle, use the outer diameter of the nozzle as the width of the current printing unit.

In this embodiment, since it is difficult to control when the width of the fuse is larger than the outer diameter of the nozzle, the maximum width of the printing unit should be limited to be smaller than or equal to the outer diameter of the nozzle. Therefore, in the planned current printing data, when the width of the current printing unit is greater than the outer diameter of the nozzle, the width of the current printing unit needs to be adjusted, that is, the outer diameter of the nozzle is taken as the width of the current printing unit, and the The moving speed or the feeding speed of the nozzle can ensure the effective control of the fuse process and the surface quality of the product.

In order to achieve the above object, the present invention also provides a 3D printer, the 3D printer includes a memory, a processor and a computer program stored in the memory and running on the processor, the computer program being processed by the processor The steps of the 3D printing method as described above are realized when the device is executed.

In order to achieve the above object, the present invention also provides a storage medium on which a control program of a 3D printer is stored, and when the control program of the 3D printer is executed by a processor, the steps of the 3D printing method described above are implemented.

Since the system introduced in the embodiments of the present invention is the system used to implement the methods in the embodiments of the present invention, those skilled in the art can understand the specific structure and deformation of the system based on the methods introduced in the embodiments of the present invention. This will not be repeated here. All systems used in the methods of the embodiments of the present invention belong to the scope of protection of the present invention.

As will be appreciated by one skilled in the art, embodiments of the present invention may be provided as a method, system, or computer program product. Accordingly, the present invention may take the form of an entirely hardware embodiment, an entirely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, the present invention may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, etc.) having computer-usable program code embodied therein.

The present invention is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It will be understood that each flow and/or block in the flowcharts and/or block diagrams, and combinations of flows and/or blocks in the flowcharts and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a general purpose computer, special purpose computer, embedded processor or controller of other programmable data processing device to produce a machine such that the instructions executed by the controller of the computer or other programmable data processing device produce Means for implementing the functions specified in one or more of the flowcharts and/or one or more blocks of the block diagrams.

These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory result in an article of manufacture comprising instruction means, the instructions An apparatus implements the functions specified in a flow or flows of the flowcharts and/or a block or blocks of the block diagrams.

These computer program instructions can also be loaded on a computer or other programmable data processing device to cause a series of operational steps to be performed on the computer or other programmable device to produce a computer-implemented process such that The instructions provide steps for implementing the functions specified in one or more of the flowcharts and/or one or more blocks of the block diagrams.

It should be noted that, in the claims, any reference signs placed between parentheses shall not be construed as limiting the claim. The word "comprising" does not exclude the presence of elements or steps not listed in a claim. The word "a" or "an" preceding an element does not preclude the presence of a plurality of such elements. The invention can be implemented by means of hardware comprising several different components and by means of a suitably programmed computer. In a unit claim enumerating several means, several of these means may be embodied by one and the same item of hardware. The use of the words first, second, and third, etc. do not denote any order. These words can be interpreted as names.

Although preferred embodiments of the present invention have been described, additional changes and modifications to these embodiments may occur to those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be construed to include the preferred embodiment and all changes and modifications that fall within the scope of the present invention.

Obviously, those skilled in the art can make various changes and modifications to the present invention without departing from the present invention

clear spirit and scope. Thus, provided that these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims (10)

1. a 3D printing method, is characterized in that, is applied to 3D printer, and described 3D printing method comprises the following steps: Determine current print data according to the print model, the current print data including at least one of the thickness and width of the current print unit at the current print position; A control parameter of the 3D printer is determined according to the current printing data, and the control parameter includes at least a target moving speed of the nozzle of the 3D printer, a target printing height of the nozzle, and a target wire feeding speed of the nozzle. One; The 3D printer is controlled to print the current printing unit according to the control parameter. 2. The 3D printing method according to claim 1, wherein the step of determining the control parameters of the 3D printer according to the current printing data comprises: When the current printing data includes the thickness of the current printing unit, the thickness of the current printing unit is used as the target printing height of the nozzle. 3. The 3D printing method according to claim 1 or 2, wherein the step of determining the control parameters of the 3D printer according to the current printing data comprises: When the current printing data includes the width of the current printing unit, acquiring the diameter of the printing wire and the preset wire feeding speed; The target moving speed of the nozzle is determined according to the current printing data, the diameter of the printing filament and the preset filament feeding speed. 4 . The 3D printing method according to claim 3 , wherein the target moving speed of the nozzle is determined according to the current printing data, the diameter of the printing filament and the preset filament feeding speed. 5 . After the steps, also include: When the target moving speed of the nozzle is greater than or equal to a first moving speed threshold, the first moving speed threshold is used to update the target moving speed of the nozzle; The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the first moving speed threshold. 5 . The 3D printing method according to claim 4 , wherein the target moving speed of the nozzle is determined according to the current printing data, the diameter of the printing filament and the preset filament feeding speed. 6 . After the steps, also include: When the target moving speed of the nozzle is less than or equal to a second moving speed threshold, the second moving speed threshold is used to update the target moving speed of the nozzle, wherein the second moving speed threshold is less than the first moving speed speed threshold; The target wire feeding speed of the nozzle is determined according to the current printing data, the diameter of the printing wire and the second moving speed threshold. 6 . The 3D printing method according to claim 4 , wherein the target filament feeding of the nozzle is determined according to the current printing data, the diameter of the printing filament and the first moving speed threshold. 7 . After the steps of speed, also include: When the target wire feeding speed of the nozzle is greater than or equal to the wire feeding speed threshold value, the target wire feeding speed of the nozzle is updated by using the wire feeding speed threshold value. 7. The 3D printing method according to claim 1, wherein the step of determining the control parameters of the 3D printer according to the current printing data comprises: Determine whether the current print data is consistent with the previous print data; When the current printing data is inconsistent with the previous printing data, the control parameters of the 3D printer are re-determined according to the current printing data. 8 . The 3D printing method according to claim 7 , wherein when the thickness of the current printing unit is smaller than the thickness of the previous printing unit, the target printing height of the nozzle is smaller than that when the previous printing unit is printing. 9 . the print height of the nozzle; and/or, When the width of the current printing unit is smaller than the width of the previous printing unit, the target moving speed of the nozzle is greater than the moving speed of the nozzle when the previous printing unit is printing, or the target feeding of the nozzle is The speed is lower than the feeding speed of the nozzle when the previous printing unit is printing. 9. The 3D printing method according to claim 1, wherein before the step of determining the control parameters of the 3D printer according to the current printing data, the method further comprises: When the current printing data includes the width of the current printing unit, acquiring the outer diameter of the nozzle of the 3D printer; When the width of the current printing unit is greater than or equal to the outer diameter of the nozzle, the outer diameter of the nozzle is used as the width of the current printing unit. 10. A 3D printer, characterized in that the 3D printer comprises a memory, a processor and a computer program stored on the memory and running on the processor, when the computer program is executed by the processor Steps for implementing a 3D printing method as claimed in any one of claims 1 to 9.

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