3D printer with negative pressure cavity

Abstract

The utility model relates to the field of 3D printing, and discloses a 3D printer with a negative pressure cavity, which comprises a printing cavity seat (1) and a lifting platform (2), the lifting platform (2) is mounted in the printing cavity seat (1) and moves up and down, the printing cavity seat (1) is a shell with an upper opening, the inner wall of the printing cavity seat (1) is provided with a first air hole (11), the inner end of the first air hole (11) is communicated with an inner cavity of the printing cavity seat (1), and the inner end of the first air hole (11) is provided with a second air hole (12). The outer end of the first air hole (11) is connected with a negative pressure assembly (3), and the negative pressure assembly (3) extracts air in the printing cavity seat (1) and forms negative pressure in the printing cavity seat (1). And a plurality of second air holes (21) are formed in the lifting platform (2). Through the arrangement of the negative pressure assembly, the product density can be effectively improved, waste of printing materials is avoided, and therefore the production efficiency is improved, and the printing device is reasonable in structure and high in practicability.

Description

TECHNICAL FIELD

[0001] The utility model relates to 3D printing field especially relates to a 3D printer with negative pressure cavity. BACKGROUND

[0002] Traditional 3D printer forming machine all use the printing head of inkjet machine to print glue and lay powder on the powder laying mechanism, and the solidified structure is generated through the adhesion of powder, so the 3D printer using this way is also called adhesive jet printer or inkjet powder printer.

[0003] But the products printed by the above-mentioned traditional 3D inkjet printer have the maximum disadvantage of strength after forming. One of the reasons leading to weak product structure strength is that a stainless steel cavity used for 3D inkjet printing has small pressure in the forming process and the gas generated in the forming process is doped in the product, thereby causing low mechanical strength of the 3D printed product, impurities in the product, and reducing the yield and reliability of the product. SUMMARY

[0004] The utility model discloses a 3D printer with negative pressure cavity to solve the technical problem of the prior art.

[0005] In order to solve the above technical problem, the utility model discloses the following technical scheme:

[0006] A D printer with negative pressure assembly, including printing cavity seat and lifting platform, lifting platform installs in printing cavity seat and moves up and down, and the printing cavity seat is a shell with an upper opening, a first air hole is arranged on the inner wall of the printing cavity seat, the inner end of the first air hole is communicated with the inner cavity of the printing cavity seat, the outer end of the first air hole is sealingly connected with the negative pressure assembly, the negative pressure assembly extracts the air in the printing cavity seat and forms negative pressure in it, and multiple second air holes are arranged on the lifting platform.

[0007] The first air hole is evenly distributed on the side wall of the printing cavity seat in a rectangular shape, the aperture of the first air hole is 10-14mm, and the interval between the centers of the adjacent two first air holes is 13-17mm.

[0008] As preferred, the outer side of the printing cavity seat is provided with a side sealing plate, the side sealing plate has two plates, the side sealing plates are arranged left and right and placed outside the first air hole, the upper end and the lower end of the side sealing plate are both provided with a sealing strip in sealing cooperation with the printing cavity seat, the side sealing plate and the outer wall of the printing cavity seat form an outer cavity, and the negative pressure assembly is communicated with the outer cavity. Since the outer cavity has no other communication space except the first air hole, the negative pressure assembly only needs to communicate with the outer cavity to uniformly extract air from the multiple first air holes.

[0009] As preferred, the negative pressure assembly comprises an upper suction fan and a lower vacuum pump, the upper suction fan is communicated with the upper part of the outer cavity, the vacuum pump is communicated with the lower part of the outer cavity, and the lower vacuum pump is further connected with a pressure control table and a vacuum cylinder.

[0010] As preferred, the inner wall of the printing cavity seat is provided with a side micro-hole side plate, which is a wave-shaped mesh plate, and the side micro-hole side plate can be used for air extraction, but the powder will be left in the middle powder area of the printing cavity seat, and the side micro-hole side plate is used for isolation of the powder and the air.

[0011] As preferred, the second air holes are vertically arranged and pass through the lifting platform; the second air holes are uniformly distributed in a rectangular shape on the lifting platform, the diameter of the second air holes is 10-14 mm, and the distance between the centers of adjacent two second air holes is 13-17 mm.

[0012] As preferred, the lifting assembly is further provided, the lifting assembly is connected with the lifting platform and drives the lifting platform to move up and down; the lifting assembly has two and is respectively located at the left and right sides of the lifting platform.

[0013] As preferred, the lifting assembly comprises a lifting motor, a screw rod, a sliding block and a sliding rail; the screw rod is vertically arranged, the lifting motor is connected with the screw rod and drives the screw rod to rotate, the sliding block is internally provided with a thread and is sleeved on the screw rod, the sliding block is matched with the vertically arranged sliding rail and moves up and down along the sliding rail, and the sliding block is connected with the lifting platform and drives the lifting platform to move up and down.

[0014] As preferred, the lifting belt is further provided, the sliding block is fixedly connected with the lifting belt, and the lifting belt is fixedly connected with the lifting platform. Through the transmission of the lifting belt, the movement of the lifting platform is more stable and reliable.

[0015] As preferred, the lower end of the lifting platform is fixedly provided with a plurality of vertically arranged positioning columns, and the printing cavity seat is internally provided with a positioning groove matched with the positioning columns. Through the arrangement of the positioning columns, the stable lifting of the lifting platform is ensured, and the printing success rate is improved.

[0016] The application has the following technical effects: the negative pressure assembly is arranged, the product density is effectively improved, the waste of printing materials is avoided, and the production efficiency is improved, and the application has reasonable structure and high practicability. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 is a structural schematic view of the application.

[0018] Figure 2 is a sectional view B-B of the application.

[0019] Figure 3 is a plan view of the utility model.

[0020] Figure 4 is a sectional view A-A of the utility model.

[0021] Figure 5 is a schematic diagram of the utility model.

[0022] The names of the parts referred to by the respective numeral designations in the drawings are as follows: 1-printing cavity seat, 2-lifting platform, 3-negative pressure assembly, 4-side sealing plate, 5-side micro-hole edge plate, 6-side middle-hole edge plate, 7-lifting assembly, 11-first air hole, 21-second air hole, 22-positioning column, 31-upper air extractor, 32-lower vacuum pump, 33-pressure control table, -vacuum cylinder, -sealing strip, 71-lifting motor, 72-screw rod, 73-sliding block, 74-sliding rail, 75-lifting belt. DETAILED DESCRIPTION

[0023] The utility model will be described in further detail below in combination with the drawings and examples. Example 1

[0024] A 3D printer with a negative pressure cavity, as shown in the figure, comprising a printing cavity seat 1 and a lifting platform 2, the lifting platform 2 is installed in the printing cavity seat 1 and moves up and down, the printing cavity seat 1 is an open shell at the top, the inner wall of the printing cavity seat 1 is provided with a first air hole 11, the inner end of the first air hole 11 is communicated with the inner cavity of the printing cavity seat 1, the outer end of the first air hole 11 is sealingly connected with a negative pressure assembly 3, the negative pressure assembly 3 extracts the air in the printing cavity seat 1 and forms a negative pressure in it; The lifting platform 2 is provided with a plurality of second air holes 21.

[0025] The first air hole 11 is evenly distributed in a rectangular shape on the side wall of the printing cavity seat 1, the aperture of the first air hole 11 is 12mm, and the interval between the centers of the adjacent two first air holes 11 is 15mm.

[0026] First, use the air extractor assembly to manufacture a fixed air flow direction around the product forming reaction zone, and the volatile gas generated in the product forming process is generally lighter than air at the same height position, which is the gas upward, so the generated air flow can attract and discharge the volatile gas generated in the product forming, and guide it to the exhaust pipe of the air extractor, so as to optimize the material purity of the product and increase the material purity and reliability.

[0027] Secondly, the product forming cavity between the powder under atmospheric pressure and the negative pressure cavity generates a pressure difference P, that is, the pressure difference (P) of the product forming cavity = atmospheric pressure (Apa) - negative pressure cavity pressure (Bpa), and a pressure difference is designed to complete the molding work in the molding powder. There is a compacting force in the relative powder of the formed pressure difference P, and the size of the compacting force is determined by the size of the pressure difference, so that the compacting force in the molded product has an absolute increase effect on the density of the product. The relationship between pressure difference and pressure is a slope curve, and the slope coefficient of the slope is 0.98. When an atmospheric pressure is equal to 101 KPA pressure value, if the intermediate negative pressure cavity is set to half (0.5 times) of the atmospheric pressure value, that is, the calculation formula of the pressure difference value of the powder is 1000kpa=10kg / ㎝², then 1kpa=0.01kg / cm², and thus 50.5kpa*0.01kg / cm²=0.5kg / cm², that is, the powder will have a pressure difference value of 50.5KPA, and the compacting force of the powder is 50.5KPA*0.01KG / CM=0.5GK / CM² pressure exists, and this compacting force can make the product forming process have stronger density and structural rigidity than the product formed under normal pressure.

[0028] The present application combines the above two ways, which can improve the purity and rigidity of the 3D printed product. Example 2

[0029] The same as example 1, except that the outer side of the printing cavity seat 1 is provided with a side sealing plate 4, the side sealing plate 4 is arranged left and right and placed outside the first air hole 11, the upper end and the lower end of the side sealing plate 4 are provided with sealing strips in sealing cooperation with the printing cavity seat 1, the side sealing plate 4 and the outer wall of the printing cavity seat 1 form an outer cavity, and the negative pressure assembly 3 communicates with the outer cavity. Since the outer cavity has no other communication space except the first air hole 11, the negative pressure assembly 3 only needs to communicate with the outer cavity to uniformly exhaust from the plurality of first air holes 11. Example 3

[0030] The same as example 1, except that the negative pressure assembly 3 includes an upper suction fan 31 and a lower vacuum pump 32, the upper suction fan 31 communicates with the upper part of the outer cavity, the vacuum pump 32 communicates with the lower part of the outer cavity, and the lower vacuum pump 32 is further connected with a pressure control table 33 and a vacuum cylinder. The function of the vacuum cylinder is to stabilize the pulsation of the lower vacuum pump 32, and the purpose is to stabilize the negative pressure of the intermediate space. The suction of the upper suction fan 31 refers to the exchange of air flow, and the designed negative pressure value is between 950pa and 850pa, mainly to exhaust the chemical reaction gas in the molding process, and the lower vacuum pump 32 is to increase the compacting force of the molding powder, so that it has a higher compacting quality in the molding process, so the negative pressure value is less than 800pa. The negative pressure value is related to the material characteristics of the molding powder.

[0031] The inner wall of the printing cavity seat 1 is provided with a side micro-hole side plate 5, which is a 400-500 mesh screen plate, and the purpose is to further distribute the pressure, and the middle negative pressure cavity is provided with a hollow plate mechanism of two layers of air exhaust (negative pressure) to ensure that the negative pressure value of the negative pressure cavity is balanced to the average negative pressure of the molding powder, and the effect is that the air can be extracted, but the powder will be left in the middle powder area of the printing cavity seat 1, which is the isolation of the powder and the air; the inner wall of the printing cavity seat 1 is provided with a side micro-hole side plate 6. Example 4

[0032] The same as example 1, except that the second air hole 21 is vertically arranged and penetrates through the lifting platform 2; the second air hole 21 is uniformly distributed in a rectangular shape on the lifting platform 2, and the diameter of the second air hole 1 is 12mm, and the distance between the centers of two adjacent second air holes 21 is 15mm. Example 5

[0033] The same as example 1, except that it further comprises a lifting assembly 7, which is connected with the lifting platform 2 and drives the lifting platform 2 to move up and down; the lifting assembly 7 has two and is respectively located on the left and right sides of the lifting platform 2.

[0034] The lifting assembly 7 comprises a lifting motor 71, a screw rod 72, a sliding block 73 and a sliding rail 74; the screw rod 72 is vertically arranged, the lifting motor 71 is connected with the screw rod 72 and drives the screw rod 72 to rotate, the sliding block 73 is internally provided with a screw thread and is sleeved on the screw rod 72, the sliding block 73 is matched with the vertically arranged sliding rail 74 and moves up and down along the sliding rail 74, and the sliding block 73 is connected with the lifting platform 2 and drives the lifting platform 2 to move up and down. The lifting motor 71 drives the screw rod 72 to rotate, and the sliding block 73 is driven by the screw rod 72 to move up and down in the sliding rail 74, so as to drive the lifting platform 2 to move up and down.

[0035] Further comprising a lifting belt 75, the sliding block 73 is fixedly connected with the lifting belt 75, and the lifting belt 75 is fixedly connected with the lifting platform 2. Through the transmission of the lifting belt 75, the movement of the lifting platform 2 is more stable and reliable.

[0036] The lower end of the lifting platform 2 is fixedly provided with a plurality of vertically arranged positioning columns 22, and the printing cavity seat 1 is provided with a positioning groove matched with the positioning column 22. Through the arrangement of the positioning column 22, the stable lifting of the lifting platform 2 can be ensured, and the printing success rate is improved.

[0037] In summary, the above only describes the preferred embodiments of the present application, and any changes and modifications made within the scope of the application should be included in the scope of the application.

Claims

1. A 3D printer with a negative pressure chamber, characterized by: It includes printing cavity seat (1) and lifting platform (2), lifting platform (2) is installed in printing cavity seat (1) and moves up and down, printing cavity seat (1) is an open top shell, the inner wall of printing cavity seat (1) is provided with first air hole (11), the inner end of first air hole (11) is communicated with the inner cavity of printing cavity seat (1), the outer end of first air hole (11) is connected with negative pressure assembly (3), negative pressure assembly (3) extracts the air in printing cavity seat (1) and forms negative pressure in it;Lifting platform (2) is provided with a plurality of second air holes (21).

2. The 3D printer with negative pressure cavity according to claim 1, characterized in that: First air hole (11) is evenly distributed on the side wall of printing cavity seat (1) in rectangular, the aperture of first air hole (11) is 10-14mm, the interval between the centers of adjacent two first air holes (11) is 13-17mm.

3. The 3D printer with negative pressure cavity according to claim 1 or 2, characterized in that: The outer side of printing cavity seat (1) is provided with side sealing plate (4), side sealing plate (4) is arranged left and right and placed outside first air hole (11), the upper end and the lower end of side sealing plate (4) are provided with sealing strip which is sealed with printing cavity seat (1), side sealing plate (4) and the outer wall of printing cavity seat (1) form outer cavity, negative pressure assembly (3) is communicated with outer cavity.

4. The 3D printer with negative pressure cavity according to claim 3, characterized in that: Negative pressure assembly (3) includes upper suction fan (31) and lower vacuum pump (32), upper suction fan (31) is communicated with the upper part of outer cavity, vacuum pump (32) is communicated with the lower part of outer cavity, lower vacuum pump (32) is further connected with pressure control table (33) and vacuum cylinder.

5. The 3D printer with negative pressure cavity according to claim 1, characterized in that: Second air hole (21) is vertically arranged and penetrates lifting platform (2);Second air hole (21) is evenly distributed on lifting platform (2) in rectangular, the aperture of second air hole (21) is 10-14mm, the interval between the centers of adjacent two second air holes (21) is 13-17mm.

6. The 3D printer with negative pressure cavity according to claim 1, characterized in that: It also includes lifting assembly (7), lifting assembly (7) is connected with lifting platform (2) and drives lifting platform (2) to move up and down;Lifting assembly (7) has two and is respectively located at the left and right sides of lifting platform (2).

7. The 3D printer with negative pressure cavity according to claim 6, characterized in that: Lifting assembly (7) includes lifting motor (71), screw rod (72), sliding block (73) and slide rail (74);Screw rod (72) is vertically arranged, lifting motor (71) is connected with screw rod (72) and drives screw rod (72) to rotate, sliding block (73) is provided with screw thread and is sleeved on screw rod (72), sliding block (73) is matched with vertically arranged slide rail (74) and moves up and down along slide rail (74), sliding block (73) is connected with lifting platform (2) and drives lifting platform (2) to move up and down.

8. The 3D printer with negative pressure cavity according to claim 7, characterized in that: It also includes lifting belt (75), sliding block (73) is fixedly connected with lifting belt (75), lifting belt (75) is fixedly connected with lifting platform (2).

9. The 3D printer with negative pressure cavity according to claim 1, characterized in that: The lower end of lifting platform (2) is fixedly provided with a plurality of positioning columns (22), and the inner wall of printing cavity seat (1) is provided with a positioning groove matched with the positioning columns (22).

10. The 3D printer with negative pressure cavity according to claim 1, characterized in that: The inner wall of printing cavity seat (1) is provided with side edge microporous edge plate (5), the number of holes of side edge microporous edge plate (5) is 400-500, and the inner wall of printing cavity seat (1) is provided with side edge microporous edge plate (6).

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