High-speed 3D ink-jet printing equipment and printing method

Abstract

The invention discloses high-speed 3D ink-jet printing equipment and a printing method, and belongs to the technical field of sand mold 3D printing, a sand paving unit of the equipment comprises a first sand paving beam and a second sand paving beam, the first sand paving beam and the second sand paving beam are located in front of and behind an ink-jet unit respectively, and a sand outlet of the second sand paving beam is higher than a sand outlet of the first sand paving beam; when the ink jet unit performs forward printing, the first sanding beam and the second sanding beam perform synchronous sanding; when the ink jet unit conducts reverse printing, the first sanding beam and the second sanding beam are not subjected to sanding, idle stroke can be avoided, the ink jet unit can conduct printing at the highest frequency in the reverse printing process, then the influence of sanding on printing is reduced, and the printing efficiency is improved.

Description

Technical Field

[0001] This invention belongs to the field of sand mold 3D printing technology, specifically relating to a high-speed 3D inkjet printing device and printing method. Background Technology

[0002] Sand mold 3D printing technology is one of the more mainstream 3D printing technologies. It uses computer-aided model reconstruction, with adhesive powdered sand as raw material and liquid binder. A sand-laying device lays a layer of sand, and an inkjet device applies a layer of binder. This process is repeated layer by layer to eventually construct a three-dimensional solid.

[0003] Most mainstream sand-mold 3D printing equipment uses a unidirectional sand-laying design, meaning the sand-laying and inkjet printing units have preset standby positions on opposite sides of the work chamber. During operation, the sand-laying unit first moves to the side closest to the inkjet printing unit, then returns to lay sand into the work chamber once before stopping at its initial standby position. The inkjet printing unit then moves towards the sand-laying unit to apply a layer of adhesive, before returning to its initial standby position. Each time a layer of sand is laid, the work chamber descends one layer, and this process is repeated to complete the 3D printing. Throughout the entire sand-laying and inkjet printing process, approximately half of the working stroke of both the sand-laying and inkjet printing units is idle, significantly lengthening the work cycle and reducing the efficiency of 3D printing.

[0004] Addressing the issue of half of the working stroke of sand-laying devices and inkjet printers being idle, some bidirectional sand-laying printing devices have been developed. For example, the utility model patent with authorization announcement number CN215697750U discloses a bidirectional sand-laying 3D sand mold printing device, including a support frame and a sand-laying mechanism mounted on the support frame. The sand-laying mechanism includes two identical sand storage tanks, a first sand storage tank and a second sand storage tank, and an inkjet cartridge positioned between the first and second sand storage tanks. The first and second sand storage tanks and the inkjet cartridge are all fixedly mounted on the support frame. The bottom of the first sand storage tank has a sand outlet hole, and a scraper parallel to the sand outlet hole is located on one side of the outlet hole. The printing device provided by this utility model uses a double-storage tank structure to achieve bidirectional sand-laying, avoiding idle travel.

[0005] Patent application CN115815529A discloses a bidirectional sand-laying 3D sand mold printing device, comprising: a frame, sand-laying guide rails and inkjet guide rails parallel to the frame, a sand-laying device slidably mounted on the sand-laying guide rails, an inkjet device slidably mounted on the inkjet guide rails, and a movable work box located below the sand-laying device and the inkjet device; the inkjet device comprises: a printing beam and an inkjet printhead slidably mounted on the printing beam, the two ends of the printing beam being slidably mounted to the inkjet guide rail on one side via support legs to form a gantry structure; the sand-laying device can pass through the gantry structure without contacting the inkjet printhead, the above structure enables the sand-laying device to lay sand during both forward and reverse strokes, avoiding empty strokes.

[0006] The existing technical solutions described above utilize one or two sand-laying devices to achieve bidirectional printing by simultaneously laying sand and printing during both forward and reverse inkjet printing, thus avoiding empty strokes. However, in sand mold 3D printing, the sand-laying speed is slow while the printing speed is fast. Therefore, although the two existing solutions mentioned above avoid empty strokes, the printing speed of the inkjet device is limited by the sand-laying speed during bidirectional printing. Summary of the Invention

[0007] The purpose of this invention is to provide a high-speed 3D inkjet printing device and printing method to solve the problem that the printing speed of the inkjet device is limited by the sand spreading speed in bidirectional inkjet printing.

[0008] To achieve the above objectives, the technical solution of the present invention is as follows: This invention provides a high-speed 3D inkjet printing device, comprising guide beams, an inkjet unit, a sand-laying unit, and a work box. Two sets of guide beams are arranged parallel and spaced apart. The inkjet unit and the sand-laying unit are located above the work box, and their ends are slidably connected to the two sets of guide beams. The sand-laying unit includes a first sand-laying beam and a second sand-laying beam, located in front of and behind the inkjet unit, respectively. The sand outlet of the second sand-laying beam is higher than that of the first sand-laying beam. When the inkjet unit prints in the forward direction, the first and second sand-laying beams simultaneously lay sand. When the inkjet unit prints in the reverse direction, neither the first nor the second sand-laying beams lay sand.

[0009] Preferably, the first and second sand-laying beams have the same sand thickness, and the height difference between the sand outlet of the second sand-laying beam and the sand outlet of the first sand-laying beam is equal to the sand thickness of the first sand-laying beam, so as to ensure that the sand layer laid by the second sand-laying beam meets the design thickness.

[0010] The present invention also relates to a printing method based on the above-mentioned high-speed 3D inkjet printing equipment, which includes the following steps: S1. Forward printing: The first sand-laying beam, the inkjet unit, and the second sand-laying beam move synchronously. Both the first and second sand-laying beams lay sand. The printing speed of the inkjet unit is adjusted according to the sand-laying speed of the first and second sand-laying beams. The inkjet unit adheres to the powder sprayed from the first sand-laying beam. S2. Lower the height of the bottom plate of the work box; S3. Reverse printing: The first sand-laying beam, the inkjet unit and the second sand-laying beam move synchronously. Neither the first sand-laying beam nor the second sand-laying beam lays sand. The inkjet unit binds the powder sprayed from the second sand-laying beam at the highest frequency. S4. Return to S1 until the printing task is completed.

[0011] Preferably, in S2, the height of the work box bottom plate that is lowered is the sum of the sand thickness of the first sand-laying beam and the second sand-laying beam. When the inkjet unit runs back and forth for one stroke, the work box bottom plate only needs to be lowered once, and this can prevent the inkjet unit from contacting the sand layer when running in the forward and reverse directions.

[0012] Preferably, in S1 and S3, the moving speeds of the first sand-laying beam, the inkjet unit, and the second sand-laying beam are all the same.

[0013] Compared with the prior art, the technical solution provided by this invention has the following advantages: The sand-laying unit of the high-speed 3D inkjet printing equipment involved in this invention includes a first sand-laying beam and a second sand-laying beam. The first sand-laying beam and the second sand-laying beam are located in front of and behind the inkjet unit, respectively. The sand outlet of the second sand-laying beam is higher than the sand outlet of the first sand-laying beam. When the inkjet unit prints in the forward direction, the first sand-laying beam and the second sand-laying beam lay sand synchronously. When the inkjet unit prints in the reverse direction, neither the first sand-laying beam nor the second sand-laying beam lays sand, so that printing is carried out at the highest frequency during reverse printing, thereby reducing the impact of sand laying on printing and improving printing efficiency. Attached Figure Description

[0014] Figure 1 This is a schematic diagram of the high-speed 3D inkjet printing equipment involved in the present invention. Figure 2 This is a schematic diagram of a high-speed 3D inkjet printer printing in the forward direction. Figure 3 This is a schematic diagram of reverse printing using a high-speed 3D inkjet printing device.

[0015] Attached reference numerals: 1-First sand-laying beam, 2-Inkjet unit, 3-Second sand-laying beam, 4-Work box bottom plate, 5-Work box, 6-Guide beam. Detailed Implementation

[0016] To further understand the content of this invention, the invention will be described in detail with reference to the embodiments. The following embodiments are used to illustrate the invention, but are not intended to limit the scope of the invention.

[0017] See attached document Figure 1 As shown, this invention provides a high-speed 3D inkjet printing device, which includes a guide beam 6, an inkjet unit 2, a sand-laying unit, and a work box 5. Two sets of guide beams 6 are arranged in parallel and spaced apart. The inkjet unit 2 and the sand-laying unit are located above the work box, and their ends are slidably connected to the two sets of guide beams. The driving mechanism for the inkjet unit 2 and the sand-laying unit is conventional technology in the art and will not be described in detail in this embodiment. The sand-laying unit includes a first sand-laying beam 1 and a second sand-laying beam 3. The first sand-laying beam 1 and the second sand-laying beam 3 are located in front of and behind the inkjet unit 1, respectively (with the forward printing direction of the inkjet unit 1 considered as the front, and the reverse printing direction considered as the rear). Generally, the first sand-laying beam 1, the inkjet unit 2, and the second sand-laying beam 3 move at the same speed, and their specifications are also the same. Therefore, the thickness of the sand laid by the first sand-laying beam 1 and the second sand-laying beam 3 is the same each time. The sand outlet of the second sand-laying beam 3 is higher than the sand outlet of the first sand-laying beam 1, and the height difference is equal to the sand-laying thickness of the first sand-laying beam 1, ensuring that the sand layer laid by the second sand-laying beam 3 meets the design thickness. The specific structures of the first sand-laying beam 1, the inkjet unit 2, and the second sand-laying beam 3 are all conventional technologies in the art and are not the subject of this invention.

[0018] When the inkjet unit 2 prints in the forward direction, the first sand-laying beam 1 and the second sand-laying beam 3 simultaneously lay sand, as shown below. Figure 2 As shown; when the inkjet unit 2 prints in reverse, neither the first sand-laying beam 1 nor the second sand-laying beam 3 lays sand, as... Figure 3 As shown, therefore, during reverse printing, the printing speed of inkjet unit 2 no longer needs to take into account the sand spreading speed, and inkjet unit 2 can print at the highest frequency to improve the printing speed.

[0019] The present invention also relates to a printing method based on the above-mentioned high-speed 3D inkjet printing equipment, which includes the following steps: S1. Refer to Appendix Figure 2As shown, inkjet unit 2 prints in the forward direction. At this time, the first sand-laying beam 1, inkjet unit 2, and second sand-laying beam 3 move synchronously. The moving speed of the first sand-laying beam 1, inkjet unit 2, and second sand-laying beam 3 is determined according to the designed sand-laying thickness and the aperture of the sand outlet of the first sand-laying beam 1 and the second sand-laying beam 3. Generally, the moving speed of the first sand-laying beam 1, inkjet unit 2, and second sand-laying beam 3 is the same, and the specifications of the first sand-laying beam 1 and the second sand-laying beam 3 are also the same. Therefore, the thickness of the sand laid by the first sand-laying beam 1 and the second sand-laying beam 3 is also the same each time. During the forward printing process, both the first sand-laying beam 1 and the second sand-laying beam 3 lay sand. The printing speed of inkjet unit 2 is adjusted according to the sand-laying speed of the first sand-laying beam 1 and the second sand-laying beam 3. Inkjet unit 2 adheres to the powder sprayed by the first sand-laying beam 1. At the same time, the sand from the second sand-laying beam 3 is laid on top of the sand sprayed by the first sand-laying beam 1 after adhesion, forming another sand layer. S2. Lower the height of the bottom plate 4 of the working box 5 (lowering the bottom plate of the working box after each layer of sand is a conventional technical means in this field). The height of the reduction is the sum of the sand thickness of the first sand-laying beam 1 and the second sand-laying beam 2, so that when the inkjet unit 2 runs back and forth for one stroke, the bottom plate 4 of the working box only needs to be lowered once, and the inkjet unit 2 can avoid contact with the sand layer when running in the forward and reverse directions. S3. See Appendix Figure 3 As shown, the inkjet unit 2 prints in reverse. At this time, the first sand-laying beam 1, the inkjet unit 2, and the second sand-laying beam 3 move synchronously. Neither the first sand-laying beam 1 nor the second sand-laying beam 3 lays sand. The inkjet unit 2 uses the highest frequency to bond the powder sprayed from the second sand-laying beam to reduce the impact of sand on printing. S4. Return to S1 until the printing task is completed.

[0020] The present invention has been described in detail above with reference to the embodiments, but the content described is only a preferred embodiment of the present invention and should not be considered as limiting the scope of the present invention. All equivalent changes and improvements made in accordance with the scope of the present invention should still fall within the patent coverage of the present invention.

Claims

1. A high-speed 3D inkjet printing device, comprising guide beams, an inkjet unit, a sand-laying unit, and a work box, wherein two sets of guide beams are arranged in parallel and spaced apart, the inkjet unit and the sand-laying unit are located above the work box, and the two ends of the inkjet unit and the sand-laying unit are slidably connected to the two sets of guide beams, characterized in that: The sand-laying unit includes a first sand-laying beam and a second sand-laying beam, which are located in front of and behind the inkjet unit, respectively. The sand outlet of the second sand-laying beam is higher than that of the first sand-laying beam. When the inkjet unit prints in the forward direction, the first and second sand-laying beams lay sand simultaneously. When the inkjet unit prints in the reverse direction, neither the first nor the second sand-laying beams lay sand.

2. The high-speed 3D inkjet printing equipment according to claim 1, characterized in that: The first and second sand-laying beams have the same sand-laying thickness, and the height difference between the sand outlet of the second sand-laying beam and the sand outlet of the first sand-laying beam is equal to the sand-laying thickness of the first sand-laying beam.

3. A printing method based on the high-speed 3D inkjet printing equipment according to claim 1, characterized in that, It includes the following steps: S1. Forward printing: The first sand-laying beam, the inkjet unit, and the second sand-laying beam move synchronously. Both the first and second sand-laying beams lay sand. The printing speed of the inkjet unit is adjusted according to the sand-laying speed of the first and second sand-laying beams. The inkjet unit adheres to the powder sprayed from the first sand-laying beam. S2. Lower the height of the bottom plate of the work box; S3. Reverse printing: The first sand-laying beam, the inkjet unit and the second sand-laying beam move synchronously. Neither the first sand-laying beam nor the second sand-laying beam lays sand. The inkjet unit binds the powder sprayed from the second sand-laying beam at the highest frequency. S4. Return to S1 until the printing task is completed.

4. The printing method based on a high-speed 3D inkjet printing device according to claim 3, characterized in that: In S2, the height of the bottom plate of the working box is reduced to the sum of the sand thickness of the first sand-laying beam and the second sand-laying beam.

5. The printing method based on a high-speed 3D inkjet printing device according to claim 3, characterized in that: In S1 and S3, the first sand-laying beam, the inkjet unit, and the second sand-laying beam all move at the same speed.

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