阅读说明：本技术 一种3d打印机和3d打印方法 (3D printer and 3D printing method ) 是由 虎鑫 彭凡 鲁云 刘轶 周志军 于 2020-06-30 设计创作，主要内容包括：本发明公开了一种3D打印机和3D打印方法,该3D打印方法包括：分别控制铺砂器和打印头向工作台板下砂和喷墨；控制所述铺砂器和所述打印头两者在水平面上沿闭环曲线运动；控制所述铺砂器和所述打印头两者或者所述工作台板在竖直方向上运动,以实现打印。上述3D打印方法不仅可以大大提高打印效率,而且可以解决由于频繁加减速而造成铺砂器和打印头的关键零部件机械寿命下降的问题。(The invention discloses a 3D printer and a 3D printing method, wherein the 3D printing method comprises the following steps: respectively controlling the sand spreader and the printing head to sand and jet ink to the working table plate; controlling both the sander and the print head to move in a closed-loop curve in a horizontal plane; controlling both the sand spreader and the print head or the work platen to move in a vertical direction to effect printing. The 3D printing method can greatly improve the printing efficiency and solve the problem that the mechanical life of key parts of the sand spreader and the printing head is shortened due to frequent acceleration and deceleration.)

1. A3D printing method, comprising:

respectively controlling the sand spreader (40) and the printing head (100) to sand and jet ink to the workbench plate (80);

controlling both the sand spreader (40) and the print head (100) to move in a closed loop curve in a horizontal plane;

controlling movement of both the sand spreader (40) and the printhead (100) or the work platen (80) in a vertical direction to effect printing.

2. The 3D printing method according to claim 1,

synchronously performing the step of controlling both the sand spreader (40) and the print head (100) to move in a closed-loop curve in a horizontal plane and the step of controlling both the sand spreader (40) and the print head (100) or the work platen (80) to move in a vertical direction to achieve helical printing;

and the step of respectively controlling the sand spreader (40) and the printing head (100) to sand and jet ink to the working table plate (80) is specifically as follows:

controlling the sand spreader (40) and the printing head (100) to respectively discharge sand and jet ink at the same preset angle with the working platen (80); and controlling the sand setting amount of the sand setting device (40) to increase along different sand setting portions far away from the center direction of the closed-loop curve, and controlling the ink jetting amount of the printing head (100) to increase along different ink jetting portions far away from the center direction of the closed-loop curve.

3. 3D printing method according to claim 2, characterized in that the step of controlling the movement of both the sand-blaster (40) and the print head (100) or the work-table (80) in the vertical direction is in particular:

controlling both the sand spreader (40) and the print head (100) to ascend in a vertical direction; alternatively, the first and second electrodes may be,

and controlling the workbench plate (80) to descend along the vertical direction.

4. 3D printing method according to claim 2, characterized in that the preset angle is in particular 0 ° -10 °.

5. The 3D printing method according to claim 1,

repeatedly executing the steps of respectively controlling the sand spreader (40) and the printing head (100) to sand and jet ink to the workbench plate (80) to the step of controlling both the sand spreader (40) and the printing head (100) or the workbench plate (80) to move in the vertical direction so as to realize layer-by-layer printing;

between the step of controlling both the sand spreader (40) and the print head (100) to move in a closed-loop curve in a horizontal plane and the step of controlling either the sand spreader (40) and the print head (100) or the work platen (80) to move in a vertical direction, further comprising:

detecting whether the movement of the sand spreader (40) and the printing head (100) along a closed-loop curve on a horizontal plane reaches a circle, if so, executing the next step;

controlling the sand spreader (40) and the printing head (100) to stop sanding and ink jetting to the working platen (80) respectively;

controlling both the sand spreader (40) and the print head (100) to stop moving in a closed loop curve on a horizontal plane;

and the step of controlling the movement of both the sand spreader (40) and the print head (100) or the work platen (80) in the vertical direction is specifically:

controlling both the sand spreader (40) and the print head (100) or the work platen (80) to move a preset distance in a vertical direction.

6. The 3D printing method according to claim 5, wherein the step of controlling the movement of both the sand-blaster (40) and the print head (100) or the work platen (80) in a vertical direction by a preset distance is in particular:

controlling both the sand spreader (40) and the print head (100) to rise a preset distance in a vertical direction; alternatively, the first and second electrodes may be,

and controlling the workbench plate (80) to descend for a preset distance along the vertical direction.

7. A3D printer, comprising: the automatic sand-spraying printing machine comprises a closed-loop track (20), a working table plate (80), a sand spreader (40) and a printing head (100), wherein the axis of the closed-loop track (20) is vertically arranged, the sand spreader (40) and the printing head (100) are connected with the closed-loop track (20), the working table plate (80) is located below the sand spreader (40) and the printing head (100), and sand and ink are respectively sprayed to the working table plate (80) through the movement of the sand spreader (40) and the printing head (100) along the closed-loop track (20) and the movement of the sand spreader (40) and the printing head (100) or the working table plate (80) in the vertical direction, so that printing is achieved.

8. The 3D printer according to claim 7, characterized in that both the sander (40) and the print head (100) are slidably connected to the closed-loop track (20), the closed-loop track (20) being provided with a first drive assembly connected to both the sander (40) and the print head (100), by the drive of which both the sander (40) and the print head (100) are made to slide along the closed-loop track (20).

9. The 3D printer according to claim 8, characterized in that both the lower sand portion of the sand spreader (40) and the ink ejection portion of the print head (100) are at the same preset angle to the work platen (80); and the number of the first and second electrodes,

the sand discharging amount of different sand discharging parts along the direction far away from the center of the closed loop track (20) is increased progressively, and the ink jetting amount of different ink jetting parts along the direction far away from the center of the closed loop track (20) is increased progressively.

10. The 3D printer according to claim 8, characterized in that the closed loop track (20) is provided with a detection portion for detecting the movement position of the sand spreader (40) and the printing head (100) along the closed loop track (20) on the horizontal plane, and the detection portion is connected with a control portion for controlling the sand spreading device (40) to sand, the printing head (100) to jet ink and the first driving component to start and stop according to the position signal transmitted by the detection portion.

11. The 3D printer according to one of the claims 7 to 10, characterized in that a guide rail is connected to the closed loop track (20), which guide rail extends in a radial direction of the closed loop track (20) and away from a center direction of the closed loop track (20), which guide rail is used for moving the sand blaster (40) and/or the print head (100) out of a printing area.

12. The 3D printer according to any of the claims from 7 to 10, characterized in that the centre of the closed loop track (20) is provided with a first feed device and a second feed device, both arranged coaxially, the first feed device interfacing with the feed opening of the sand spreader (40) to achieve the sanding, and the second feed device interfacing with the feed opening of the print head (100) to achieve the inking.

13. The 3D printer according to any of claims 7 to 10, characterized in that the sand-blaster (40) and the print head (100) are a one-piece assembly.

14. The 3D printer according to any one of claims 7 to 10, characterized in that the number of the sand-spreaders (40) and the print heads (100) is plural, and all the sand-spreaders (40) and all the print heads (100) are arranged along the circumference of the closed-loop track (20).

Technical Field

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

Background

Along with the 3D printing technology is mature day by day, the sand mould 3D printer that the casting field used has obtained the wide application, and the work box of conventional sand mould 3D printer generally is the rectangle, and printable work piece size has been decided to the work box size of rectangle.

In the prior art, the 3D printer includes a sand spreader, a print head, and a work table, the work table is disposed inside the work box and can move along an axial direction of the work box, the sand spreader and the print head are both disposed above the work table through a sliding mechanism, and the sand spreader and the print head are both distributed on both sides of a printing area; during printing, firstly, a layer of sand material is paved on the working table plate by the sand paving device, then the printing head with the ink jet function sprays liquid material to the sand material on the working table plate once, after printing of the layer is completed, the working table plate descends by one layer thickness, and the steps are repeated, so that the liquid material mixed in the sand material and the liquid material sprayed out of each layer of the printing head are subjected to chemical reaction to generate solidification, and then a product is printed. However, in the printing process, the sand spreader and the printing head cannot work simultaneously, that is, after the sand spreader spreads a layer of sand, the printing head can perform ink jet, which determines that the printing efficiency is not very high, and in the printing process of the rectangular work box, the sand spreader and the printing head both move in a reciprocating manner, and are not suitable for performing printing in the acceleration and deceleration process, which wastes time and greatly affects the printing efficiency, and it often takes several hours or even dozens of hours to print each box of product, thereby becoming the bottleneck of the 3D printer in the development of the casting field.

Therefore, how to avoid the low printing efficiency of the conventional 3D printer is a technical problem that needs to be solved by those skilled in the art.

Disclosure of Invention

The invention aims to provide a 3D printing method, which can enable a sand spreader and a printing head to work in a closed-loop track simultaneously and continuously, thereby greatly improving the printing efficiency; meanwhile, the reduction of the mechanical life of key parts of the 3D printer caused by frequent acceleration and deceleration can be avoided. Another object of the present invention is to provide a 3D printer.

In order to achieve the above object, the present invention provides a 3D printing method, comprising:

respectively controlling the sand spreader and the printing head to sand and jet ink to the working table plate;

controlling both the sander and the print head to move in a closed-loop curve in a horizontal plane;

controlling both the sand spreader and the print head or the work platen to move in a vertical direction to effect printing.

Optionally, the step of controlling both the sand spreader and the print head to move along a closed-loop curve in a horizontal plane and the step of controlling both the sand spreader and the print head or the work platen to move in a vertical direction are performed synchronously to achieve helical printing;

and the step of respectively controlling the sand spreader and the printing head to sand and jet ink to the working table plate comprises the following steps:

controlling the sand spreader and the printing head to respectively discharge sand and jet ink at the same preset angle with the working table plate; and controlling the sand-laying device to increase the sand-laying amount of different sand-laying parts along the direction far away from the center of the closed-loop curve, and controlling the printing head to increase the ink-jetting amount of different ink-jetting parts along the direction far away from the center of the closed-loop curve.

Optionally, the step of controlling the movement of both the sand spreader and the print head or the work table in the vertical direction specifically includes:

controlling both the sand spreader and the print head to ascend in a vertical direction; alternatively, the first and second electrodes may be,

and controlling the workbench plate to descend along the vertical direction.

Optionally, the preset angle is specifically 0 ° to 10 °.

Optionally, the step of respectively controlling the sanding device and the printing head to sand and jet ink to the workbench plate to the step of controlling both the sanding device and the printing head or the workbench plate to move in the vertical direction is repeatedly executed to realize layer-by-layer printing;

between the step of controlling both the sander and the print head to move in a closed-loop curve in a horizontal plane and the step of controlling either the sander and the print head or the work platen to move in a vertical direction, further comprising:

detecting whether the movement of the sand spreader and the printing head on the horizontal plane along a closed-loop curve reaches a circle, if so, executing the next step;

respectively controlling the sand spreader and the printing head to stop sanding and ink jetting to the working table plate;

controlling both the sander and the print head to stop moving along a closed-loop curve on a horizontal plane;

and the step of controlling movement of both the sand spreader and the print head or the work table in the vertical direction is specifically:

and controlling the sand spreader and the printing head or the working table plate to move for a preset distance in the vertical direction.

Optionally, the step of controlling both the sand spreader and the print head or the work platen to move in the vertical direction by a preset distance specifically includes:

controlling the sand spreader and the printing head to ascend in the vertical direction for a preset distance; alternatively, the first and second electrodes may be,

and controlling the workbench plate to descend for a preset distance along the vertical direction.

The present invention also provides a 3D printer, comprising: the automatic sand-spraying printing machine comprises a closed-loop track, a working table plate, a sand spreader and a printing head, wherein the axis of the closed-loop track is vertically arranged, the sand spreader and the printing head are connected with the closed-loop track, the working table plate is located below the sand spreader and the printing head, the sand spreader and the printing head move along the closed-loop track and respectively perform sand and ink spraying on the working table plate, and the sand spreader and the printing head or the working table plate moves in the vertical direction, so that printing is realized.

Optionally, both the sander and the print head are slidably connected to the closed loop track, the closed loop track is provided with a first drive assembly connected to both the sander and the print head, and both the sander and the print head are driven by the first drive assembly to slide along the closed loop track.

Optionally, both the lower sanding portion of the sanding device and the ink ejection portion of the print head are at the same preset angle with the work platen; and the number of the first and second electrodes,

the sand discharging amount of different sand discharging parts along the direction far away from the center of the closed loop track is increased progressively, and the ink jetting amount of different ink jetting parts along the direction far away from the center of the closed loop track is increased progressively.

Optionally, the closed-loop track is provided with a detection portion for detecting the movement position of the sand spreader and the printing head on the horizontal plane along the closed-loop track, and the detection portion is connected with a control portion for controlling the sand falling of the sand spreader, the ink jetting of the printing head and the start and stop of the first driving assembly according to a position signal transmitted by the detection portion.

Optionally, the closed loop track is connected with a guide rail, the guide rail extends along the radial direction of the closed loop track and far away from the central direction of the closed loop track, and the guide rail is used for moving the sand spreader and/or the printing head out of the printing area.

Optionally, the center of the closed-loop track is provided with a first feeding device and a second feeding device, the first feeding device and the second feeding device are coaxially arranged, the first feeding device is in butt joint with a feed opening of the sand spreader to realize sand adding, and the second feeding device is in butt joint with a feed opening of the printing head to realize ink adding.

Optionally, the sander and the printhead are a unitary assembly.

Optionally, the number of the sand-laying devices and the number of the printing heads are both multiple, and all the sand-laying devices and all the printing heads are arranged along the circumferential direction of the closed-loop track.

The invention designs a 3D printing method aiming at different requirements of 3D printing, and particularly relates to the 3D printing method which comprises the following steps:

respectively controlling the sand spreader and the printing head to sand and jet ink to the working table plate;

controlling the sand spreader and the printing head to move along a closed-loop curve on a horizontal plane;

both the sanders and the print heads or the work table are controlled to move in the vertical direction to effect printing.

Meanwhile, the invention also provides a 3D printer, the 3D printing method can be applied to the 3D printer, and the 3D printer comprises the following steps: the sand-blasting machine comprises a closed-loop track, a working table plate, a sand-blasting device and a printing head, wherein the axis of the closed-loop track is vertically arranged, the sand-blasting device and the printing head are connected with the closed-loop track, and the working table plate is positioned below the sand-blasting device and the printing head.

The 3D printer can realize spiral printing and layer-by-layer printing by executing the 3D printing method, namely, the sand spreader and the printing head move along a closed-loop track and respectively perform sand discharging and ink jetting towards the working table plate, and the sand spreader and the printing head or the working table plate move in the vertical direction to realize printing.

In this way, the 3D printer can enable the sand spreader and the printing head to continuously work along the closed-loop track by executing the 3D printing method, and in the printing process, the 3D printer can be set such that the sand spreader and the printing head rotate and print while the working table plate descends, or the sand spreader and the printing head rotate and print while the working table plate ascends, thereby realizing spiral printing; the sand spreader and the printing head can rotate to print one layer first and then the working table plate descends one layer thick, or the sand spreader and the printing head rotate to print one layer first and then the sand spreader and the printing head ascend one layer thick, so that the layer-by-layer printing is realized. Compared with the traditional printer in which the sand spreader and the printing head cannot work simultaneously, and the sand spreader and the printing head are not suitable for printing in the acceleration and deceleration process, the setting mode can greatly improve the printing efficiency and solve the problem that the mechanical life of key parts of the sand spreader and the printing head is reduced due to frequent acceleration and deceleration.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

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

fig. 2 is a schematic diagram of a spiral cutting diagram of a 3D printer according to an embodiment of the present invention during spiral printing;

fig. 3 is a schematic diagram of a cutting diagram of a variable pitch (layer thickness) of a 3D printer during spiral printing according to an embodiment of the present invention;

fig. 4(a) is a schematic diagram of a 3D printer provided by an embodiment of the present invention with box printing;

fig. 4(b) is a schematic diagram of boxless printing of a 3D printer provided by an embodiment of the invention;

fig. 5(a) is a schematic diagram of multi-box printing of a 3D printer provided by an embodiment of the present invention;

fig. 5(b) is a schematic diagram of single-box printing of a 3D printer provided by an embodiment of the present invention;

FIG. 6 is a schematic diagram illustrating sand laying amount control of a sand laying device in a 3D printer according to an embodiment of the invention;

fig. 7(a) is a schematic diagram illustrating ink ejection amount control of a spiral printing printhead in a 3D printer according to an embodiment of the present invention;

fig. 7(b) is a schematic diagram illustrating ink ejection amount control of a print head for spiral printing in a 3D printer according to an embodiment of the present invention;

fig. 8 is a schematic view illustrating an assembly structure of a suspended print head in a 3D printer according to an embodiment of the present invention;

fig. 9 is a bottom view of a multi-printhead arrangement in a 3D printer provided by an embodiment of the invention;

FIG. 10 is a flow chart of a spiral printing method according to an embodiment of the present invention;

fig. 11 is a flowchart of a layer-by-layer printing method according to an embodiment of the present invention.

Wherein:

10-bracket, 11-workpiece, 12-sanding printing integrated piece, 13-rotation center line, 14-printing area, 20-closed loop track, 201-fixed block, 202-stator, 203-slide rail, 204-slide block, 205-rotor, 206-mounting plate, 207-connecting plate, 30-work box, 40-sanding device, 50-first guide rail, 60-conveying roller way, 70-fixed bottom plate, 80-work table plate, 90-second guide rail, 100-printing head, 110-rotation shaft, 120-spiral cutting track, 130-spiral cutting workpiece and 140-variable pitch spiral cutting track.

Detailed Description

The core of the invention is to provide a 3D printing method, which can lead a sand spreader and a printing head to work in a closed loop track simultaneously and continuously, thereby greatly improving the printing efficiency; meanwhile, the reduction of the mechanical life of key parts of the 3D printer caused by frequent acceleration and deceleration can be avoided. Another core of the invention is to provide a 3D printer.

It should be noted that the following directional terms such as "upper end, lower end, left side, right side" and the like are defined based on the drawings of the specification.

The 3D printing method provided by the embodiment of the invention comprises the following steps:

the sand spreader 40 and the print head 100 are respectively controlled to sand and jet ink to the work table plate 80;

controlling both the sanders 40 and the print heads 100 to move in a closed-loop curve in a horizontal plane;

both the sanders 40 and the print heads 100 or the work platen 80 are controlled to move in the vertical direction to effect printing.

The 3D printing method can enable the sand spreader 40 and the printing head 100 to continuously work along a closed-loop curve on a horizontal plane, and in the printing process, the 3D printing method can realize spiral printing: both the sander 40 and the print head 100 rotate to print, the platen descends, or both the sander 40 and the print head 100 rotate to print and ascend.

Layer-by-layer printing can of course also be achieved: both the sanders 40 and the print heads 100 rotate to print one layer first and then the work table is lowered one layer thick, or both the sanders 40 and the print heads 100 rotate to print one layer first and then both the sanders 40 and the print heads 100 are raised one layer thick.

Compared with the traditional printer in which the sand spreader 40 and the printing head 100 cannot work simultaneously, and the sand spreader 40 and the printing head 100 are not suitable for printing in the acceleration and deceleration process, the setting mode not only can greatly improve the printing efficiency, but also can solve the problem that the mechanical life of key parts of the sand spreader 40 and the printing head 100 is reduced due to frequent acceleration and deceleration.

Specifically, as shown in fig. 10, the spiral printing method may be configured as follows:

s1: controlling the sand spreader 40 and the printing head 100 to respectively discharge sand and jet ink at the same preset angle with the workbench plate 80; the sanding amount of different sanding parts of the sanding device 40 along the direction far away from the center of the closed-loop curve is controlled to increase progressively, and the ink jet amount of different ink jet parts of the printing head 100 along the direction far away from the center of the closed-loop curve is controlled to increase progressively;

s2: the step of controlling both the sander 40 and the print head 100 to move in a closed-loop curve in the horizontal plane and the step of controlling both the sander 40 and the print head 100 or the work platen 80 to move in the vertical direction are performed simultaneously to achieve helical printing.

During spiral printing, the cutting software adopts a spiral cutting method, namely, the cutting software is distributed along the rotation direction in a spiral surface mode, so that the spiral cutting work piece can be printed along the spiral cutting track. The sand spreader 40 and the printing head 100 are at the same preset angle with the work table plate 80 to respectively discharge sand and jet ink, that is, in the spiral printing process, the printing plane is not horizontal, the sand spreader 40 and the printing head 100 are not horizontally arranged, but are arranged in parallel with the sand surface on the work table plate 80, and the included angle between the sand spreader 40 and the printing head 100 and the horizontal plane is the rising angle of the spiral surface.

It should be noted that theoretically, the rising angle of the spiral surface is larger than 0 degree and smaller than 90 degrees. In practice, however, the rise angle of the helicoid is no greater than 10 degrees or less, and in an embodiment of the invention, the preset angle of both the sander 40 and the printhead 100 to the platen 80 is specifically 0-10 °.

Meanwhile, in the spiral printing process, the sand spreader 40 and the printing head 100 do not move linearly, and in the inner side and the outer side of the rotating motion, because the speeds of the sand spreader 40 and the printing head 100 relative to the sand surface are different, the sand dropping amount and the ink jetting amount are different, at this time, the sand spreader 40 and the printing head 100 need to be in a certain functional relationship in the radial direction of the sand surface instead of being kept unchanged all the time, for example, the sand spreader 40 can be set to gradually increase the sand dropping amount of different sand dropping portions in the direction away from the center of the closed-loop curve, and the printing head 100 can be set to gradually increase the ink jetting amount of different ink jetting portions in the direction away from the center of the closed-loop curve. Of course, the sand dropping amount of the sand spreader 40 and the ink jetting amount of the print head 100 may be automatically adjusted according to the movement trajectory, or may be adjusted according to parameters such as the printing layer thickness and the sand granularity, which will not be described herein again.

On the basis of the above, the step of controlling the movement of both the sander 40 and the print head 100 or the work deck 80 in the vertical direction is specifically: controlling both the sand blaster 40 and the print head 100 to ascend in a vertical direction; alternatively, the table plate 80 is controlled to descend in the vertical direction.

That is, the spiral printing may be: the control of both the sander 40 and the print head 100 to move along the closed-loop curve in the horizontal plane and the control of both the sander 40 and the print head 100 to ascend in the vertical direction are performed in synchronization, or the control of both the sander 40 and the print head 100 to move along the closed-loop curve in the horizontal plane and the control of the work platen 80 to descend in the vertical direction are performed in synchronization.

Besides, as shown in fig. 11, the layer-by-layer printing method may be configured as follows:

s101: the sand spreader 40 and the print head 100 are respectively controlled to sand and jet ink to the work table plate 80;

s102: controlling both the sanders 40 and the print heads 100 to move in a closed-loop curve in a horizontal plane;

s103: detecting whether the movement of the sand spreader 40 and the printing head 100 along the closed-loop curve on the horizontal plane reaches a circle, if so, executing the next step;

s104: the sand spreader 40 and the print head 100 are respectively controlled to stop sanding and ink jetting to the work platen 80; controlling both the sanders 40 and the print heads 100 to stop moving in a closed-loop curve on a horizontal plane;

s105: controlling both the sander 40 and the print head 100 or the work platen 80 to move a preset distance in the vertical direction;

s106: the steps of controlling the sanding device 40 and the print head 100 to sand and jet ink toward the work table 80, respectively, to the step of controlling both the sanding device 40 and the print head 100 or the work table 80 to move in the vertical direction by a preset distance are repeatedly performed to achieve layer-by-layer printing.

In other words, the layer-by-layer printing method requires that when both the sander 40 and the print head 100 move in a closed-loop curve in the horizontal plane for one revolution, the sander 40 and the print head 100 are controlled to stop sanding and ejecting ink to the work table 80, and both the sander 40 and the print head 100 are controlled to stop moving in a closed-loop curve in the horizontal plane, and then, the step of controlling both the sander 40 and the print head 100 or the work table 80 to move in the vertical direction is performed.

Further, controlling both the sander 40 and the print head 100 or the work platen 80 to move in the vertical direction by a preset distance is specifically: controlling both the sand blaster 40 and the print head 100 to ascend in a vertical direction by a preset distance; or controls the table plate 80 to be lowered by a predetermined distance in the vertical direction.

According to the 3D printer provided by the embodiment of the present invention, the 3D printing method can be applied to the 3D printer, as shown in fig. 1 to 9 of the specification, the 3D printer includes: the system comprises a closed-loop track 20, a work table plate 80, a sand spreader 40 and a printing head 100, wherein the axis of the closed-loop track 20 is vertically arranged, the sand spreader 40 and the printing head 100 are both connected with the closed-loop track 20, and the work table plate 80 is positioned below the sand spreader 40 and the printing head 100.

The 3D printer described above can realize spiral printing and layer-by-layer printing by performing the 3D printing method described above, that is, printing is realized by moving both the sander 40 and the print head 100 along the closed-loop track 20 and sanding and ejecting ink to the work platen 80 and by moving both the sander 40 and the print head 100 or the work platen 80 in the vertical direction, respectively.

To accomplish the above printing, both the sander 40 and the print head 100 are slidably connected to the closed-loop track 20, and the closed-loop track 20 is provided with a first driving assembly connected to both the sander 40 and the print head 100, and both the sander 40 and the print head 100 are slid along the closed-loop track 20 by the driving of the first driving assembly.

As shown in the attached fig. 1 of the specification, the 3D printer further includes a support 10, and a work box 30, a fixed bottom plate 70 for supporting the work box 30, and a roller conveyor 60 for conveying the work box 30 are disposed inside the support 10; the work table 80 is arranged in the work box 30, the bottom of the work table 80 is provided with a driving device for driving the work table 80 to descend, the sand spreader 40 and the printing head 100 are arranged above the work box 30 and can be suspended at the bottom of the closed-loop track 20, the closed-loop track 20 is fixedly arranged on the bracket 10, so that the sand spreader 40 and the printing head 100 can rotate around a central rotating shaft 110, and simultaneously, the sand spreader 40 and the printing head 100 run along the closed-loop track 20 due to the limitation of the closed-loop track 20.

It should be noted that the closed-loop track 20 referred to herein refers to a circular track having a closed track, and the closed-loop track 20 includes, but is not limited to, a circular track, an elliptical track, a square track, and any other structure that enables the sand-laying device 40 and the print head 100 to synchronously run along the closed track, and the sand-laying device 40 and the print head 100 preferably run in the same track, but may also run in different tracks, for example, two tracks concentrically arranged are provided for the sand-laying device 40 and the print head 100 to run respectively.

Furthermore, the first driving assembly may be specifically configured as a linear motor, the linear motor can control the sand spreader 40 and the printing head 100 to continuously move along the closed track of the closed-loop track 20, and the sand spreader 40 and the printing head 100 can move at a constant speed or a controllable speed until the printing is finished.

Of course, the first driving assembly may also be configured as other mechanisms, such as an electric hydraulic thruster, and the electric hydraulic thruster integrates a motor, a centrifugal pump, and an oil cylinder into a whole, and the driving control process of the electric hydraulic thruster may refer to the prior art.

It should be noted that the sand spreader 40 and the print head 100 may be provided integrally, that is, they are provided as a sand-spreading printing integrated piece 12, and one set or multiple sets may be provided for the sand-spreading printing integrated piece 12; the sand spreader 40 and the print head 100 may also be separately arranged, and when the sand spreader 40 and the print head 100 are separately arranged, the number of the sand spreader 40 and the print head 100 may be adjusted according to actual needs, which is not limited in this document.

When both the sand pavers 40 and the print heads 100 are provided in plural numbers, all the sand pavers 40 are distributed along the circumferential direction of the closed-loop rail 20, and all the print heads 100 are also distributed along the circumferential direction of the closed-loop rail 20.

In the printing process, the sand spreader 40 spreads sand continuously in a single direction, the printing head 100 ejects ink continuously in a single direction, the sand spreader 40 and the printing head 100 can run clockwise or anticlockwise, and the sand spreader 40 and the printing head 100 can be guaranteed to run in the same direction until the printing is finished.

To facilitate maintenance of the sander 40 and/or the print head 100, the closed-loop track 20 is connected to rails that are located radially of the closed-loop track 20 and away from the center of the closed-loop track 20, and the rails can be positioned by the carriage 10 for movement of the sander 40 and/or the print head 100 out of the print zone.

That is, for the structure in which the sand spreader 40 and the print head 100 are separated, the 3D printer may be provided with a first guide rail 50 and a second guide rail 90, and the first guide rail 50 and the second guide rail 90 are used for the sand spreader 40 and the print head 100 to move out of the printing area, respectively, for maintenance, repair, and inspection; for the structure with the sand-laying device 40 and the printing head 100 integrated, the 3D printer can be provided with a separate device for moving the sand-laying printing integrated piece 12 out of the printing area to realize the functions of maintenance, repair and inspection.

During printing, rotary printing of the sander 40 and the print head 100 can be achieved by continuously operating along the closed loop track 20, which can include various forms such as spiral printing and layer-by-layer printing. It should be noted that the rotary printing is premised on the requirement that the print head 100, the sand spreader 40 and the sand surface be kept at a fixed distance.

In addition, when printing layer by layer, the 3D printer still needs to be equipped with detection portion and control portion, this detection portion can set up in the orbital preset position of closed loop (for example the initial position of sanding device 40 and the initial position of beating the motion of printer head 100), detection portion is used for detecting both sanding device 40 and printer head 100 along closed loop track 20 position of motion on the horizontal plane, detection portion specifically can set up to position sensor or distance sensor, detection portion is connected with the control portion, the control portion is used for controlling sanding device 40 according to the position signal control that detection portion transmitted and puts down sand, printer head 100 inkjet and first drive assembly start-stop.

In this way, when both the sander 40 and the print head 100 move in the closed-loop curve on the horizontal plane for one revolution, the detection section may transmit the signal to the control section, so that the control section controls the sander 40 and the print head 100 to stop sanding and ejecting ink to the work platen 80 and controls both the sander 40 and the print head 100 to stop moving in the closed-loop curve on the horizontal plane, and then, performs the step of controlling both the sander 40 and the print head 100 or the work platen 80 to move in the vertical direction.

As shown in fig. 2, in the spiral printing, the cutting software adopts a spiral cutting method, i.e. the cutting software is distributed along the rotation direction in a spiral surface manner, so as to print the spiral cutting workpiece 130 along the spiral cutting path 120. In the running process of the sand spreader 40 and the printing head 100, the working table plate 80 also moves downwards, in the running process, the sand spreader 40, the printing head 100 and the working table plate 80 are in motion correlation, the printing head 100 and the sand spreader 40 can do uniform motion and can also do acceleration and deceleration motion, the motion characteristic of the corresponding bottom plate is also changed, but the distance from the sand spreader 40 to the sand surface is ensured to be one layer thickness, and the distance from the printing head 100 to the sand surface is kept constant. According to the configuration of the computer, the image cutting software can cut the product in the whole work box 30 into one picture or a plurality of pictures, and if the product is cut into the plurality of pictures, the splicing treatment is carried out in the printing process. In the spiral printing process, the sand spreader 40, the printing head 100 and the working table plate 80 do continuous relative movement, so that the problem of descending precision of the working table plate 80 in the traditional printing mode is solved.

Depending on the number of sanders 40 and print heads 100, the pattern may be cut into a single spiral or multiple spirals. One spiral corresponds to one set of sanding printing device and multiple spiral corresponds to multiple sets of sanding printing device, wherein one set of sanding printing device can comprise a sanding device and a printing head.

Furthermore, since the printing plane is not horizontal due to the spiral cut pattern, both the lower sanding portion of the sanders 40 and the ink ejection portion of the print head 100 are at the same preset angle to the platen 80. Specifically, the lower sand portion of the sand layer 40 is not horizontally arranged, but is parallel to the sand surface, and the included angle between the lower sand portion of the sand layer 40 and the horizontal plane is also the rising angle of the helicoid. The same principle exists in the print head 100, and in order to ensure that the ink ejection part of the print head 100 is at the same distance from the sand surface, the ink ejection part of the print head 100 needs to be parallel to the sand surface, which requires that the ink ejection part of the print head 100 has an included angle with the horizontal plane, and the included angle is the rising angle of the spiral surface. Theoretically, the rising angle of the spiral surface is larger than 0 degree and smaller than 90 degrees. In practice, however, the rise angle of the helicoid is not greater than 10 degrees or less.

Of course, in the above-described spiral printing, one layer thickness corresponds to one pitch. According to the printing needs, to the more printing product of surface special type curved surface, can reduce the bed thickness when printing the curved surface, make and print the layer line littleer, can use variable bed thickness (variable pitch) cutting method, the concrete expression is: the pitch of the spiral cut pattern is changed, i.e., the product is printed along the variable pitch spiral cut pattern track 140, as shown in fig. 3.

Specifically, when the sand applicator 40 and the print head 100 are arranged to sand-coat the integrated body 12, the distance of the sand surface with respect to the sand-coat printing integrated body 12 is dynamic for the printing method of the helicoid cut in the revolution printing, and the sand-coat printing integrated body 12 is revolved with respect to the rotation center line 13, and the work platen 80 is slowly lowered to print the corresponding work piece 11 in the tank, as shown in fig. 4(a) of the specification.

Of course, a boxless printing method can be adopted, when the boxless printing is carried out, the printing head 100 and the sand spreader 40 or the sand-spreading printing integrated piece 12 rotate and move, the side rises, no boundary exists around the printing area 14, and the boundary is printed in the printing process, and the method is also suitable for the occasions of the multiple printing heads 100 and the multiple sand spreaders 40, as shown in the specification and the attached figure 4(b), as long as the distance between the printing head 100 and the sand spreader 40 and the sand surface is within a fixed distance.

The printing area where the above described sand applicator 40 and the printing head 100 make a revolving motion around a point or a curve may be a revolving area composed of one or more work tanks 30, that is, a circular or ring-shaped work tank 30 may be provided singly or by means of a plurality of splices, depending on the size of the work tank 30; fig. 5(a) is a schematic diagram illustrating multi-box printing of a 3D printer according to an embodiment of the present invention, and fig. 5(b) is a schematic diagram illustrating single-box printing of a 3D printer according to an embodiment of the present invention.

Preferably, the small-sized work box 30 uses an integral single work box 30, and when the radius of gyration is too large, a manner of splicing a plurality of work boxes 30 is used. In the splicing mode, each work box 30 can be spliced into a large work box 30 for printing by using independent small units or removing side plates according to the size of a printing workpiece.

In the embodiment of the present invention, the sand discharge amount of the different sand discharge portions in the direction away from the center of the closed-loop track 20 is increased progressively; and the amount of ink ejected by the different inkjets in a direction away from the center of the closed loop track 20 increases.

Specifically, because the sand layer 40 moves non-linearly, i.e., the velocities of the sand layer 40 relative to the sand surface are different between the inner side and the outer side of the sand layer 40, the sand amount requirement is different, which requires that the sand discharge amount is not constant along the length of the sand layer 40, but rather is a function of the length of the sand layer, as shown in fig. 6 of the specification.

In the description and the attached fig. 6, the sand layer 40 is arranged along the radial direction of the closed-loop track 20, and the sand dropping amount of the sand layer 40 in different sand dropping portions away from the direction of the rotation center increases progressively, wherein the abscissa is the distance between the different sand dropping portions of the sand layer 40 and the rotation center, and the ordinate is the sand dropping amount corresponding to the different sand dropping portions. That is, the sand setting amount of the sand paver 40 which makes a circular revolution is larger as it is farther from the rotation center. The sand discharge gap of the sand spreader 40 can be automatically adjusted according to different tracks, and the sand discharge amount can also be automatically adjusted according to different setting formulas of parameters such as the layer thickness of the spread sand, the granularity of the sand and the like.

Correspondingly, because the motion of the print head 100 also has the problem that the linear velocity of one side is fast relative to the sand surface and the linear velocity of the other side is slow, the ink jet amount of the print head 100 is different, and the specific solution method is represented by two aspects:

first, by selecting nozzles with different ink jetting amounts (the ink jetting portion may be specifically configured as a nozzle provided with a plurality of nozzle holes), the nozzle with a large ink jetting amount is selected from the nozzles located outside the rotation radius, and the nozzle with a small ink jetting amount is selected from the nozzles located inside the rotation radius, as shown in fig. 7(a) of the specification, the print head 100 in fig. 7(a) is arranged along the radial direction of the closed-loop track 20, and the ink jetting amounts of the different nozzles (the nozzle holes in any nozzle have the same ink jetting amount) in the direction away from the rotation center of the print head 100 are increased, where the abscissa is the distance between the different nozzles in the print head 100 and the rotation center, and the ordinate is the ink jetting amount corresponding to the different.

Secondly, by adjusting the waveform file of each nozzle, the ink ejection amount of each row of nozzle holes of different nozzles is controlled to be different, as shown in fig. 7(b) of the specification, in fig. 7(b), the print head 100 is arranged along the radial direction of the closed-loop track 20, the ink ejection amount of different nozzles (different ink ejection amounts of nozzle holes in any nozzle) of the print head 100 along the direction away from the rotation center increases, wherein the abscissa is the distance between the different nozzles in the print head 100 and the rotation center, and the ordinate is the ink ejection amount corresponding to the different nozzles. This shows that the ink ejection amount increases linearly with the radius, for example, the ink ejection amount is distributed as a linear function with the radius. Of course, the ink jet amount can be set according to other curve rules according to actual printing requirements.

The printing process of the suspended connection is specifically described below by taking a linear motor as an example.

In order to facilitate the movement of the sand spreader 40 and the print head 100 along the closed-loop track 20, the closed-loop track 20 may be provided with a slide rail 203, the slide rail 203 may be provided with an i-shaped slide rail 203 or a dovetail groove-shaped slide rail 203, and accordingly, the slide rail 203 is provided with a slider 204 which is engaged with the slide rail 203 and can slide relative to the slide rail 203, and the slider 204 is connected with the sand spreader 40 and the print head 100, so that the sand spreader 40 and the print head 100 can move along the closed-loop track 20 by the sliding of the slider 204 relative to the slide rail 203.

Specifically, the closed-loop track 20 may be a track with a C-shaped cross section, that is, the closed-loop track 20 includes a track body and two arms disposed at two ends of the track body, and the sliding rail 203 and the sliding block 204 are disposed in a preset space formed by the two arms.

Preferably, as shown in fig. 8 in the specification, the C-shaped track is fixed on the support 10 at the upper part of the C-shaped track by fixing blocks 201 at both sides of the C-shaped track, a stator 202 is arranged at the middle position of the bottom of the C-shaped track, and the stator 202 should have the same structure as the closed-loop track 20, for example, a circular structure; two slide rails 203 are arranged in the C-shaped track, the two slide rails 203 are respectively arranged on two sides of the stator 202, slide blocks 204 are connected on the slide rails 203 on any side, the mover 205 is arranged right below the stator 202, the mover 205 is connected with the slide blocks 204 on the two sides through a mounting plate 206 positioned below the mover 205, and the lower end of the mounting plate 206 is connected with the printing head 100 (or can be arranged into a sanding printing integrated piece 12 or a sanding device 40 according to needs) through a connecting plate 207. Thus, when an ac power supply is applied, the stator 202 and the mover 205 have good electromagnetic field coupling, and the mover 205 can drive the sanding printing integrated member 12 or the print head 100 or the sanding device 40 to move along the closed-loop track 20 under the action of the electromagnetic thrust.

Of course, the driving devices of the sand spreader 40 and the print head 100 can be separated according to actual needs, that is, two sets of concentric closed-loop tracks 20 are used for respectively realizing the movement of the sand spreader 40 and the print head 100, and if the sand spreader and the print head operate in different tracks, two sets of stators 202 and movers 205 of linear motors are required to be arranged. For example, multiple stators 202 may be arranged within the closed loop track 20 as space permits, i.e., by suspending multiple sets of sanders 40 and printheads 100 to increase efficiency, with the printheads 100 and sanders 40 spaced apart, and so printing cyclically.

Specifically, when the sand spreader 40 and the print head 100 are separately arranged, a plurality of sand spreaders 40 and a plurality of print heads 100 can be arranged to work simultaneously within the range of the path scanned by the print head 100 and the sand spreader 40, the number of print heads 100 can be adjusted according to the actual printing requirement, and when one print head 100 is arranged, the print head 100 is required to be wide enough to cover the entire printing area 14; when a plurality of print heads 100 are provided, the projection of the travel paths of the plurality of print heads 100 on the bottom surface of the work box 30 can completely cover the bottom surface of the work box 30, and the print heads 100 can be in a modular design, and the print heads 100 which do not need to be printed can be removed or deactivated according to the actual complement rate. If a particular print head 100 is damaged, it can be quickly replaced.

As shown in fig. 9 in the description, when the number of the print heads 100 is multiple, the number of the movers 205 is also multiple, the multiple movers 205 share one stator 202, and the multiple movers 205 are distributed along the circumferential direction of the stator 202, for example, a first mover for driving the sand blaster 40 to move and a plurality of second movers for driving the print heads 100 may be provided.

When the sand spreader 40 and the printing head 100 are integrally arranged, one set of sand spreading can be arranged in the revolving body to print the integrated piece 12, and a plurality of sets of sand spreading can also be arranged to print the integrated piece 12, if a plurality of sets of sand spreading are arranged to print the integrated piece 12, a plurality of turns of helicoid cutting drawings are required to be used when front cutting drawings are printed, otherwise, one turn of helicoid cutting drawings are used.

Besides the above-mentioned suspended connection, the above-mentioned sand spreader 40 and the printing head 100 may also be supported connection, that is, the sand spreader 40 and the printing head 100 may be disposed above the closed-loop track 20 through a connection component, and in this case, the sand spreader 40 and the printing head 100 need to be driven by a driving mechanism disposed at the center of rotation; for example, the closed-loop track 20 may be disposed outside the work box 30, the closed-loop track 20 may be supported by a bottom supporting device (which may be the bracket 10), the upper end of the print head 100 (or the sand-laying device 40 or the sand-laying printing integrated piece 12) is supported and fixed to the slide block 204 on the closed-loop track 20 by a first connecting assembly, and the upper end of the print head 100 is further provided with a second connecting assembly connected to a driving mechanism at the center of rotation, so that the print head 100 can slide through the slide block 204 above the track to realize the movement along the track under the driving of the driving mechanism.

Further, in order to ensure the continuous movement of the sand spreader 40 and the printing head 100, the 3D printer is further provided with a first feeding device and a second feeding device, wherein the first feeding device and the second feeding device are both arranged at the center of the closed-loop track 20, the first feeding device is in butt joint with the feed opening of the sand spreader 40 to realize sand adding, and the second feeding device is in butt joint with the feed opening of the printing head 100 to realize liquid material supply.

More specifically, for a circular rotary printing mode in which the sanding device 40 and the printing head 100 are in a supporting connection and the center of rotation is constant, the rotating shaft 110 at the center of rotation may serve as a pivot for the sanding device 40 and the printing head 100. Because the linear velocity of rotation center department is zero, consequently can set up sand adding pipe and feed tube at the rotation center, the two coaxial settings of sand adding pipe and feed tube, the feed tube can set up in the inside of sand adding pipe, of course, the liquid material also can be followed the upside supply of printer head 100, sand adding pipe and feed tube can realize the feed through rotary joint and the charge door of sanding ware 40 and the charge door butt joint of printer head 100 respectively, the grit can be followed the downside and used the sand pump to pump in sanding ware 40.

In the embodiment of the present invention, the rotation center may be changed for the rotation motion of various types of closed-loop paths, and at this time, the liquid may be supplied by a follower type supply device, which may be disposed outside the working tank 30.

Specifically, liquid material is supplied from the upper sides of the sand spreader 40 and the printing head 100, the feeding pipeline can move for a distance along with the feeding port of the printing head 100 or the sand spreader 40, the relative positions of the feeding port and the feeding pipeline are kept unchanged during the movement, feeding is finished when the maximum feeding stroke is reached, the feeding device returns to the feeding starting point, the next feeding period is waited for, and the last action is repeated until the sand spreader 40 and the printing head 100 pass through the feeding area next time and need to be fed.

In order to achieve helical printing of the sanders 40 and the print heads 100 with the work platen 80 stationary, the 3D printer is further provided with a second drive assembly connected to the sanders 40 and/or the print heads 100 for driving the axial movement of the sanders 40 and/or the print heads 100 along the closed-loop track 20, thereby achieving an axial translational movement on the basis of the rotational movement of the sanders 40 and/or the print heads 100.

The second driving assembly may specifically include a driving motor and a ball screw, wherein an upper end of a screw of the ball screw is connected to the driving motor, and a screw nut of the ball screw is connected to the printing head 100 (or the sand spreader 40 or the sand-spreading printing integrated unit 12). Thus, the driving motor drives the screw rod to rotate, and the screw rod drives the screw nut and the printing head 100 to ascend. Of course, the arrangement of the ball screw can be referred to the prior art.

In addition, in order to ensure the stability of the ascending of the print head 100 (or the sand spreader 40 or the sand-spreading printing integrated unit 12), a guiding mechanism, such as a combination of a guide rod and a guide sleeve, may be provided between the print head 100 and the connecting plate 207 above the print head 100 on both sides of the ball screw, so that the print head 100 can ascend smoothly under the guiding action of the guide rod and the guide sleeve.

It is noted that, in this specification, relational terms such as first and second, and the like are used solely to distinguish one entity from another entity without necessarily requiring or implying any actual such relationship or order between such entities.

The 3D printer and the 3D printing method provided by the present invention are described in detail above. The principles and embodiments of the present invention are explained herein using specific examples, which are provided only to help understand the concepts of the present invention and the core concepts thereof. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.