阅读说明：本技术 一种热床偏移的打印头修正打印方法及其应用的3d打印机 (Printing head correction printing method for hot bed offset and 3D printer applying printing head correction printing method ) 是由 梁沅龙 刘荣廷 于 2019-11-16 设计创作，主要内容包括：本发明公开了一种热床偏移的打印头修正打印方法及其应用的3D打印机,包括如下步骤：建立以热床中心点为原点的空间直角坐标系；在热床的打印面设置有呈矩阵排布的多个标记点,其中,每个标记点具有确定的x坐标和y坐标；打印头以同一高度移动至热床中心点以及每个标记点的上方,分别获取每个标记点的实际z坐标；将热床中心点的z坐标作为所有标记点的基准z坐标,建立针对于呈矩阵排布的多个标记点的空间变化矩阵；基于空间变化矩阵修正打印头的打印移动轨迹。本发明能在一定程度上提高打印效率。(The invention discloses a printing head correction printing method for hot bed offset and a 3D printer using the same, which comprises the following steps: establishing a spatial rectangular coordinate system with the central point of the hot bed as the origin; a plurality of mark points arranged in a matrix form are arranged on the printing surface of the hot bed, wherein each mark point has a determined x coordinate and a determined y coordinate; the printing head moves to the center point of the hot bed and above each marking point at the same height, and the actual z coordinate of each marking point is respectively obtained; taking the z coordinate of the central point of the hot bed as a reference z coordinate of all the mark points, and establishing a spatial variation matrix for the mark points which are arranged in a matrix; and correcting the printing movement track of the printing head based on the spatial variation matrix. The invention can improve the printing efficiency to a certain extent.)

1. A printing method for correcting a printing head with offset of a heat bed is characterized by comprising the following steps:

establishing a spatial rectangular coordinate system with the central point of the hot bed (3) as the origin;

a plurality of mark points arranged in a matrix form are arranged on the printing surface of the hot bed (3), wherein each mark point has a determined x coordinate and a determined y coordinate;

the printing head (4) moves to the central point of the hot bed (3) and above each marking point at the same height, and the actual z coordinate of each marking point is respectively obtained;

taking the z coordinate of the central point of the hot bed (3) as the reference z coordinate of all the mark points, and establishing a spatial variation matrix for a plurality of mark points which are arranged in a matrix;

the printing movement locus of the printing head (4) is corrected based on the spatial variation matrix.

2. The method for printing with the modified print head having the offset thermal bed according to claim 1, wherein the number of rows and columns of the matrix of the plurality of marking points is the same and completely covers the printing surface of the thermal bed (3).

3. The method for printing by correcting the printing head with the offset of the heat bed as claimed in claim 1, wherein the z coordinate of the central point of the heat bed (3) is used as the reference z coordinate of all the mark points, and a space variation matrix for a plurality of mark points arranged in a matrix is established, comprising the following steps:

taking the z coordinate of the central point of the hot bed (3) as the reference z coordinate of all the marking points, wherein each marking point is provided with a corresponding x coordinate, y coordinate, actual z coordinate and reference z coordinate;

dividing a plurality of mark points which are arranged in a matrix into at least one matrix partition according to a preset breadth;

calculating according to a formula (I) based on each mark point in the matrix partition to establish a spatial change matrix for each matrix partition, wherein the formula (I) is as follows:

。

4. the method as claimed in claim 3, wherein the predetermined width is the width between adjacent mark points.

5. A method according to claim 3, wherein the printing movement track of the print head (4) is corrected based on a spatial variation matrix, comprising the steps of:

acquiring a printing moving track of a printing head (4) in a space rectangular coordinate system, wherein the printing moving track is a set of a plurality of coordinate points in the space rectangular coordinate system, and each coordinate point has a reference coordinate;

substituting the reference coordinate of each coordinate point into the space change matrix of the corresponding matrix partition, and calculating to obtain the actual offset coordinate corresponding to the coordinate point;

the printing moving track of the printing head (4) is corrected.

6. A3D printer applying the printing head correction printing method of the heat bed offset according to any one of claims 1 to 5 is characterized by comprising a rack (1), a heat bed (3) arranged on the rack (1), and a printing head (4) arranged above the heat bed (3), wherein an x-axis moving mechanism (5), a y-axis moving mechanism (6) and a z-axis moving mechanism (7) for controlling the printing head (4) to form a printing moving track above the heat bed (3) are arranged on the rack (1), and a detection switch (8) is arranged on the lower end face of the printing head (4).

7. A3D printer according to claim 6, characterised in that the detection switch (8) is a contact switch or a capacitive proximity switch.

8. The 3D printer according to claim 7, characterized in that the print head (4) comprises an extruder (41) and a print nozzle (42), the print nozzle (42) is arranged on the lower end face of the extruder (41), the detection switch (8) is arranged on the lower end face of the extruder (41), and the bottom end of the detection switch (8) is located at a lower level than the bottom end of the print nozzle (42).

Technical Field

The invention relates to the technical field of correction methods, in particular to a printing head correction printing method for hot bed offset and a 3D printer applying the printing head correction printing method.

Background

The rapid prototyping technology, also called 3D printing, is a high and new manufacturing technology based on a material accumulation method, which can manufacture a real object or a real model by a prototyping device in a material accumulation manner according to three-dimensional model data of a part or an object.

The basic principle of 3D printing is layered processing and superposition molding, i.e. a 3D entity is generated by adding materials layer by layer, when 3D printing is performed, a three-dimensional model of an object to be printed is obtained by a computer through modes of design, scanning, etc., a series of digital slices are completed along a certain direction by a computer aided design technology (e.g. CAD), information of the slices is transmitted to a 3D printer, a machine instruction is generated by the computer according to the slices, a thin layer is printed by the 3D printer according to the machine instruction, and the continuous thin layers are stacked until a solid object is molded to form a three-dimensional solid object, thereby completing 3D printing.

With the continuous development of 3D printing technology, a desktop type 3D printer is a device which heats wires such as ABS, PLA and the like to a molten state, then superposes layer by layer and finally forms. Before the 3D printer works, the hot bed in the 3D printer needs to be leveled, namely, the distance between the printing head and any point of the hot bed is equal, otherwise, the forming precision of parts and samples and even whether forming can be influenced.

At present, the leveling of the heat bed adopts the mode that a probe is arranged on a printing head to detect the height of each corner of the heat bed, then a nut of the heat bed is screwed to adjust the height of the heat bed, the heat bed can be printed after being leveled by repeated operation, and the overall printing efficiency of the 3D printer is lower, so that certain improvement is provided.

Disclosure of Invention

Aiming at the defects in the prior art, the invention aims to provide a printing head correction printing method for hot bed offset, which can improve the printing efficiency to a certain extent.

The technical purpose of the invention is realized by the following technical scheme:

a printing method for correcting a printing head with offset of a heat bed comprises the following steps:

establishing a spatial rectangular coordinate system with the central point of the hot bed as the origin;

a plurality of mark points arranged in a matrix form are arranged on the printing surface of the hot bed, wherein each mark point has a determined x coordinate and a determined y coordinate;

the printing head moves to the center point of the hot bed and above each marking point at the same height, and the actual z coordinate of each marking point is respectively obtained;

taking the z coordinate of the central point of the hot bed as a reference z coordinate of all the mark points, and establishing a spatial variation matrix for the mark points which are arranged in a matrix;

and correcting the printing movement track of the printing head based on the spatial variation matrix.

Preferably, among the plurality of marking points arranged in a matrix, the number of rows and columns of the matrix is the same and completely covers the printing surface of the hot bed.

Preferably, the method for establishing the spatial variation matrix for the plurality of mark points arranged in the matrix by taking the z coordinate of the center point of the hot bed as the reference z coordinate of all the mark points comprises the following steps:

taking the z coordinate of the central point of the hot bed as a reference z coordinate of all the mark points, wherein each mark point is provided with a corresponding x coordinate, a corresponding y coordinate, a corresponding actual z coordinate and a corresponding reference z coordinate;

dividing a plurality of mark points which are arranged in a matrix into at least one matrix partition according to a preset breadth;

calculating according to a formula (I) based on each mark point in the matrix partition to establish a spatial change matrix for each matrix partition, wherein the formula (I) is as follows:

。

preferably, the preset breadth is the breadth between the adjacent mark points.

Preferably, the method for correcting the printing movement track of the printing head based on the spatial variation matrix comprises the following steps:

acquiring a printing moving track of a printing head in a space rectangular coordinate system, wherein the printing moving track is a set of a plurality of coordinate points in the space rectangular coordinate system, and each coordinate point has a reference coordinate;

substituting the reference coordinate of each coordinate point into the space change matrix of the corresponding matrix partition, and calculating to obtain the actual offset coordinate corresponding to the coordinate point;

and correcting the printing moving track of the printing head.

Aiming at the defects in the prior art, the invention aims to provide a 3D printer applying a printing head correction printing method of hot bed offset, which can improve the printing efficiency to a certain extent.

The technical purpose of the invention is realized by the following technical scheme:

the 3D printer applying the printing head correction printing method based on the heat bed offset comprises a rack, a heat bed arranged on the rack and a printing head arranged above the heat bed, wherein an x-axis moving mechanism, a y-axis moving mechanism and a z-axis moving mechanism are arranged on the rack and used for controlling the printing head to form a printing moving track above the heat bed, and a detection switch is arranged on the lower end face of the printing head.

Preferably, the detection switch is a contact switch or a capacitive proximity switch.

Preferably, the printing head comprises an extruder and a printing nozzle, the printing nozzle is arranged on the lower end face of the extruder, the detection switch is arranged on the lower end face of the extruder, and the horizontal plane where the bottom end of the detection switch is located is lower than the horizontal plane where the bottom end of the printing nozzle is located.

In summary, compared with the prior art, the beneficial effects of the invention are as follows:

this application is through defining the hotbed central point as the benchmark, all regard the hotbed central point as the reference with each mark point, thereby obtain the produced skew degree of each mark point position in the hotbed, move the orbit through the printing to the printer head and revise, so that the printer head can revise the slope skew of removal in order to adapt to the hotbed at the printing in-process on the z axle direction, thereby the process of adjusting the hotbed by manual screw nut before having removed from printing, the preparation time of adjusting the hotbed gradient in a large number has been practiced thrift, in order to improve printing efficiency to a certain extent.

Drawings

Fig. 1 is a schematic structural diagram of a 3D printer according to a technical solution of the present invention;

FIG. 2 is a front view of a 3D printer according to an embodiment of the present invention;

FIG. 3 is a schematic flow chart of a printing head correction printing method for hot bed offset according to the present invention;

FIG. 4 is a schematic diagram of a process for establishing a spatial variation matrix according to the present invention;

fig. 5 is a schematic diagram of a correction process of a printing movement track of a print head according to an embodiment of the present invention.

Reference numerals: 1. a frame; 2. installing a base; 3. heating the bed; 4. a print head; 41. an extruder; 42. a printing nozzle; 5. an x-axis moving mechanism; 51. mounting a bracket; 52. a mounting seat; 53. an x-axis servo motor; 54. an x-axis synchronous belt body; 6. a y-axis moving mechanism; 61. a y-axis servo motor; 62. a y-axis synchronous belt body; 7. a z-axis moving mechanism; 71. mounting a rail; 72. a z-axis servo motor; 73. driving the screw rod; 8. a detection switch.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. It should be noted that: the relative arrangement of parts and steps set forth in these embodiments does not limit the scope of the present invention unless specifically stated otherwise.

The following description of at least one exemplary embodiment is merely illustrative in nature and is in no way intended to limit the invention, its application, or uses. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention. Techniques, methods, and apparatus known to those of ordinary skill in the relevant art may not be discussed in detail but are intended to be part of the specification where appropriate.

In the prior art, the leveling of the heat bed 3 adopts the mode that a probe is arranged on a printing head 4 to detect the height of each corner of the heat bed 3, then the height of the heat bed 3 is adjusted by screwing a nut of the heat bed 3, and the heat bed 3 can be printed after being leveled by repeating multiple operations.

Aiming at the defects of the prior art, the plurality of mark points arranged in a matrix mode are arranged on the printing surface of the hot bed 3, wherein the center point of the hot bed 3 is defined as a datum point, and the center point of the hot bed 3 is used as a reference point for each mark point, so that the offset degree generated by the position of each mark point in the hot bed 3 is obtained, and the printing moving track of the printing head 4 is corrected, so that the printing head 4 can be self-adaptive to the inclined offset of the hot bed 3 in the printing process, the process of manually leveling the hot bed 3 by spending a large amount of time is omitted, and the printing efficiency is improved.

Specifically, as shown in fig. 1, the invention provides a 3D printer, which is applied to a printing head correction printing method of heat bed offset, wherein the 3D printer includes a frame 1, a mounting base 2 is slidably arranged on the frame 1, a heat bed 3 is arranged on the mounting base 2, and four corners of the heat bed 3 are connected to the mounting base 2 through screw and nut assemblies, so that the heat bed 3 can swing on the mounting base 2 by screwing the screw and nut assemblies to manually adjust the inclination angle of the heat bed 3.

Wherein, a printing head 4 is arranged above the heating bed 3, and an x-axis moving mechanism 5, a y-axis moving mechanism 6 and a z-axis moving mechanism 7 for controlling the printing head 4 to form a printing moving track above the heating bed 3 are arranged on the frame 1. In this embodiment, the x-axis moving mechanism 5 and the z-axis moving mechanism 7 control the print head 4 to move in the x-axis direction and the z-axis direction, and the y-axis moving mechanism 6 controls the mounting base 2 to move in the y-axis direction, so that a print moving track of the print head 4 is formed.

y axle moving mechanism 6 includes y axle servo motor 61, first y axle synchronous pulley, second y axle synchronous pulley and y axle synchronous belt body 62, first y axle synchronous pulley and second y axle synchronous pulley rotate respectively and install in the both sides of frame 1, y axle synchronous belt body 62 cladding is on first y axle synchronous pulley and second y axle synchronous pulley, installation base 2 is fixed on y axle synchronous belt body 62, the output shaft of y axle servo motor 61 is on first y axle synchronous pulley, y axle moving mechanism 6 drives installation base 2 and slides so that hotbed 3 moves along y axle direction.

The x-axis moving mechanism 5 comprises a mounting bracket 51, a mounting seat 52, an x-axis servo motor 53, a first x-axis synchronous pulley, a second x-axis synchronous pulley and an x-axis synchronous belt 54, the mounting bracket 51 is arranged above the heating bed 3, the mounting seat 52 is slidably mounted on the mounting bracket 51 along the x-axis direction, the first x-axis synchronous pulley and the second x-axis synchronous pulley are respectively rotatably mounted on two sides of the mounting bracket 51, the x-axis synchronous belt 54 is wrapped on the first x-axis synchronous pulley and the second x-axis synchronous pulley, the mounting seat 52 is fixed on the x-axis synchronous belt 54, the printing head 4 is arranged on the mounting bracket 51, and the x-axis moving mechanism 5 drives the mounting seat 52 to slide so as to drive the printing head 4 to move along the x-axis direction.

At least one z-axis moving mechanism 7 is arranged, in this embodiment, the number of the z-axis moving mechanisms 7 is two, the two z-axis moving mechanisms 7 are arranged on two sides of the mounting bracket 51, each z-axis moving mechanism 7 includes a mounting rail 71, a z-axis servo motor 72 and a driving screw rod 73, the mounting bracket 51 is slidably arranged on the mounting rail 71 and can slide along the z-axis direction, the driving screw rod 73 is in threaded connection with the mounting bracket 51, an output shaft of the z-axis servo motor 72 is connected to the driving screw rod 73, and the z-axis moving mechanism 7 drives the mounting bracket 51 to slide so that the printing head 4 moves along the z-axis direction.

As shown in fig. 1 and 2, the lower end surface of the print head 4 is provided with a detection switch 8. In one embodiment, the detection switch 8 is a contact switch; in another embodiment, the detection switch 8 is a capacitive proximity switch. It should be noted that the print head 4 includes an extruder 41 and a print nozzle 42, the extruder 41 is disposed on the mounting seat 52, the print nozzle 42 is disposed on the lower end surface of the extruder 41, the detection switch 8 is disposed on the lower end surface of the extruder 41, and the bottom end of the detection switch 8 is located at a lower level than the bottom end of the print nozzle 42. In one embodiment, the bottom end of the detection switch 8 is located at a distance of 0.5cm below the level of the bottom end of the print nozzle 42.

Therefore, when 3D printing is performed, a three-dimensional model of a part model to be printed is obtained by a computer through a design, scanning and the like, a series of digital slices are completed in a certain direction by a computer aided design technology (such as CAD), for example, the digital slices are completed in a horizontal direction, and information of the slices is transmitted to a controller of the 3D printer, wherein the slice information includes contour information of the section of each slice in the part model, the slice thickness of each slice in the part model and the like.

When the first layer slice is printed, the controller controls the printing head 4 to move along the profile of the section of the first layer slice (the profile is the printing moving track of the printing head 4) through the x-axis moving mechanism 5, the y-axis moving mechanism 6 and the z-axis moving mechanism 7 according to the profile information of the section of the first layer slice, and the 3D printing material sprayed by the printing head 4 is cooled and solidified on the printing surface of the hot bed 3 so as to form the profile shape of the section of the first layer slice.

In the next layer slicing molding, the controller controls the printing head 4 to move along the profile of the next layer slicing section through the x-axis moving mechanism 5, the y-axis moving mechanism 6 and the z-axis moving mechanism 7 according to the profile information of the next layer slicing section, and the 3D printing material sprayed by the printing head 4 is cooled and solidified on the profile shape of the first layer for superposition. And repeating the actions, stacking the continuous slices until a solid object is molded to form a three-dimensional part model, and finishing the 3D printing.

Therefore, when the heat bed 3 is not leveled before 3D printing, which will cause the print head 4 to print on the first layer, the distance that the print head 4 moves to the print surface of the heat bed 3 is deviated. Therefore, the present application can know the inclination of each position of the thermal bed 3 in advance, and further correct the printing movement locus of the print head 4.

As shown in fig. 3, the method for correcting printing by a print head with offset thermal bed according to the present invention includes the following steps:

step S100, establishing a spatial rectangular coordinate system with the central point of the hot bed 3 as an origin;

step S200, a plurality of mark points arranged in a matrix are arranged on the printing surface of the hot bed 3, wherein each mark point has a certain x coordinate and y coordinate.

According to the technical scheme defined in the steps S100 to S200, specifically, the spatial rectangular coordinate system in the present application uses the center point of the thermal bed 3 as an origin, so that the horizontal plane where the center point of the printing surface of the thermal bed 3 is located is an x-axis and y-axis interactive area surface in the spatial rectangular coordinate system, and the vertical direction of the center point of the thermal bed 3 is a z-axis.

This application is a plurality of mark points that the matrix was arranged through the setting of the face of printing at hot bed 3, and in this application, in being a plurality of mark points that the matrix was arranged, the line number and the column number that the matrix was arranged are the same and cover the face of printing of hot bed 3 completely. In this embodiment, the number of rows and columns in the matrix arrangement is five. Wherein, the establishment of each mark point is established in a virtual way, each mark point has a definite x coordinate and y coordinate, for example, starting from the mark point coordinate at the upper left corner, the mark points can be respectively recorded as (-10, 10, z), (-5, 10, z), (0, 10, z) … …, (0, -10, z), (5, -10, z), (10, -10, z). However, since the thermal bed 3 is tilted, the z-coordinate of each marked point cannot be determined. Therefore, the actual z-coordinate of each marker point needs to be determined.

Step S300, the printing head 4 moves to the central point of the heat bed 3 and above each marking point at the same height, and the actual z coordinate of each marking point is respectively obtained.

According to the technical scheme defined in step S300, specifically, the print head 4 first moves to above the central point of the heat bed 3 and rises to a first height, for example, the first height is 10cm, then the x-axis servo motor 53, the y-axis servo motor 61, and the z-axis servo motor 72 in the x-axis moving mechanism 5, the y-axis moving mechanism 6, and the z-axis moving mechanism 7 are reset to zero to maintain a zero point, and the print head 4 is controlled to move downward until the detection switch 8 on the print head 4 touches the printing surface of the heat bed 3, at which time, the print head 4 stops moving downward and records a downward moving height value of the first height. It should be noted that the moving distance of the print head 4 realized by the number of pulses input to the x-axis servo motor 53, the y-axis servo motor 61, and the z-axis servo motor 72 in the x-axis moving mechanism 5, the y-axis moving mechanism 6, and the z-axis moving mechanism 7 may be set according to specific situations, and the embodiment is not particularly limited. As in the present application, the x-axis servomotor 53 inputs a pulse number, the print head 4 moves a distance of 1cm along the x-axis, and the x-coordinate of the print head 4 in the established spatial rectangular coordinate system is changed to 1.

And then, according to the x coordinate and the y coordinate of one of the mark points, moving the mark point to the position above the mark point at the same height of the first height, moving the printing head 4 downwards until the detection switch 8 on the printing head 4 touches the printing surface of the heat bed 3, stopping moving the printing head 4 downwards at the moment, recording the moving height value, and repeating the actions to obtain the moving-down height value of the printing head 4 staying above each mark point at the first height.

The origin of the space rectangular coordinate is arranged on the central point of the heat bed 3, so that the downward moving height value of the central point of the heat bed 3 is used as a reference standard, the downward moving height of each mark point is compared with the downward moving height value of the central point of the heat bed 3, and the obtained difference value is the actual z coordinate of each mark point. If the height value of the center point of the thermal bed 3 moving downward is 10cm, the print head 4 stays at the first mark point (-10, 10, z) at the first height, and the height value of the print head 4 moving downward is 10.1cm, wherein the difference is 0.1cm, therefore, the actual coordinate of the first mark point is (-10, 10, 0.1), and similarly, the actual z coordinate of each mark point can be obtained, and details are not repeated here.

And step S400, taking the z coordinate of the central point of the hot bed 3 as the reference z coordinate of all the mark points, and establishing a spatial variation matrix aiming at a plurality of mark points which are arranged in a matrix.

According to the technical solution defined in step S400, specifically, since the center point of the hot bed 3 is set as the origin, the coordinate of the center point of the hot bed 3 is (0, 0, 0), and therefore, the reference coordinate of the first mark point should be (-10, 10, 0), and the actual coordinate of the first mark point should be (-10, 10, 0.1), it can be seen that the position of the hot bed 3 at the first mark point is offset. Therefore, it is necessary to use the z coordinate of the center point of the thermal bed 3 as the reference z coordinate of all the marked points, and establish a spatial variation matrix for a plurality of marked points arranged in a matrix, as shown in fig. 4, including the following steps:

step S410, taking the z coordinate of the center point of the hot bed 3 as the reference z coordinate of all the mark points, wherein each mark point is provided with a corresponding x coordinate, y coordinate, actual z coordinate and reference z coordinate;

step S420, dividing a plurality of mark points which are arranged in a matrix into at least one matrix partition according to a preset breadth;

step S430, calculating according to a formula (I) based on each mark point in the matrix partition to establish a spatial variation matrix for each matrix partition, wherein the formula (I) is as follows:

。

according to the technical solution defined in steps S410 to S430, in particular, in this embodiment, the breadth between adjacent mark points is used as the preset breadth. Therefore, in the present embodiment, the plurality of marker points of the matrix arrangement of 5 × 5 are divided into 16 matrix partitions, and therefore, each matrix partition will have a corresponding spatial variation matrix.

Here, taking the first matrix partition in the upper left corner as an example for explanation, it can be obtained that:

the reference coordinate of the first marking point is (-10, 10, 0), and the actual coordinate of the first marking point is (-10, 10, 0.1);

the reference coordinate of the second marking point is (-10, 10, 0), and the actual coordinate of the first marking point is (-5, 10, 0.2);

the reference coordinate of the sixth marking point is (-10, 5, 0), and the actual coordinate of the sixth marking point is (-10, 5, -0.1);

the reference coordinate of the seventh marking point is (-5, 5, 0), and the actual coordinate of the seventh marking point is (-5, 5, -0.2);

and respectively substituting the reference coordinate and the actual coordinate of the first mark point, the reference coordinate and the actual coordinate of the second mark point, the reference coordinate and the actual coordinate of the sixth mark point and the reference coordinate and the actual coordinate of the seventh mark point into a formula I to obtain a spatial variation matrix of the first matrix partition. In the same way, the spatial variation matrix of each matrix partition can be obtained, and the description is not repeated here.

In step S500, the printing movement locus of the print head 4 is corrected based on the spatial variation matrix.

According to the technical solution defined in step S500, specifically, as shown in fig. 5, the method includes the following steps:

step S510, obtaining a printing moving track of the printing head 4 in a space rectangular coordinate system, wherein the printing moving track is a set of a plurality of coordinate points in the space rectangular coordinate system, and each coordinate point has a reference coordinate;

step S520, substituting the reference coordinate of each coordinate point into the space change matrix of the corresponding matrix partition, and calculating and obtaining the actual offset coordinate corresponding to the coordinate point;

in step S530, the printing movement locus of the print head 4 is corrected.

According to the technical scheme defined in the steps S510 to S530, specifically, when the printing head 4 needs to print the first-layer slice, the contour information of the cross section of the first-layer slice is acquired to form a printing moving track of the printing head 4 in the spatial rectangular coordinate system, where the printing moving track is a set of a plurality of coordinate points in the spatial rectangular coordinate system, and each coordinate point has a reference coordinate. If the thermal bed 3 is offset, the printing is performed according to the printing movement trajectory, which causes a distance deviation between the drop point of the print head 4 and the printing surface of the thermal bed 3.

Therefore, when the printing movement track of the print head 4 is corrected, first, the matrix partition where each coordinate point is located in the printing movement track is determined, and then the reference coordinate of each coordinate point is substituted into the spatial variation matrix corresponding to the matrix partition, so that the actual offset coordinate of each coordinate point is calculated and obtained, and then the printing movement track of the print head 4 is corrected according to the actual offset coordinate, the print head 4 performs first-layer printing according to the corrected printing movement track, and the print head 4 can perform correction movement in the z-axis direction at the position where the deviation occurs in the thermal bed 3.

In the next layer of slice forming, the controller forms a printing moving track of the printing head 4 in a space rectangular coordinate system according to the profile information of the next layer of slice section, the profile information of each layer of slice section is suitable for due to the arrangement of the space change matrix of each corresponding matrix partition, the actual offset coordinate of each coordinate point position in the printing moving track is calculated through the method, the printing moving track is corrected, and the printing of the printing head 4 on the next layer of slice section can be completed.

And repeating the actions, stacking the continuous slices until a solid object is molded to form a three-dimensional part model, and finishing the 3D printing.

Therefore, the center point of the heat bed 3 is defined as the reference point, and each mark point takes the center point of the heat bed 3 as the reference point, so that the offset degree generated by the position of each mark point in the heat bed 3 is obtained, and the printing moving track of the printing head 4 is corrected, so that the printing head 4 can be corrected and moved in the z-axis direction in the printing process to adapt to the inclined offset of the heat bed 3, and the printing efficiency is improved to a certain extent.

The above description is intended to be illustrative of the present invention and not to limit the scope of the invention, which is defined by the claims appended hereto.