Powder supply device suitable for SLM metal 3D printer

Abstract

The powder supply device suitable for the SLM metal 3D printer comprises a powder leakage prevention blanking device and a first driving unit, the powder leakage prevention blanking device comprises a stirring bin and a powder supply bin located on the lower portion of the stirring bin, the stirring bin is used for stirring metal powder, and a rotatable powder supply shaft is concentrically installed in a cylindrical cavity of the powder supply bin; the first driving unit is connected with the powder supply shaft and used for driving the powder supply shaft to rotate; a plurality of powder feeding grooves in the axial direction of the powder supply shaft are formed in the powder supply shaft in the axial direction of the powder supply shaft; a powder inlet is formed in the upper portion of the powder supply bin, a powder outlet is formed in the lower portion of the powder supply bin, and the powder inlet and the powder outlet are distributed on the two sides of the vertical center line of the powder supply bin. The stirring bin communicates with the powder supply bin through a first flow channel, and the first flow channel communicates with the powder inlet. In the powder supply process, stirring can be completed, powder hardening can be prevented, powder leakage can be effectively prevented, meanwhile, powder can be quantitatively supplied, the structure is compact, and equipment miniaturization is achieved.

Description

Technical Field

[0001] The present invention belongs to the technical field of SLM metal 3D printing equipment, and particularly relates to a powder feeding device suitable for an SLM metal 3D printer. Background Art

[0002] During the printing process of SLM metal 3D printing equipment, it is necessary to quantitatively supply powder to the equipment. However, due to the small particle size of metal powder, loose and uniform powder is required during printing. Also, because the fluidity of metal powder is good, powder leakage is likely to occur on the powder spreading device during the powder feeding process. Therefore, a powder feeding device that can prevent powder caking, prevent powder leakage, and quantitatively supply powder is needed. Summary of the Invention

[0003] Aiming at the above technical problems, the present invention provides a powder feeding device suitable for an SLM metal 3D printer, which can complete stirring to prevent powder caking, effectively prevent powder leakage, and quantitatively supply powder during the powder feeding process, with a compact structure and miniaturized equipment.

[0004] To achieve the above object, the technical solution of the present invention is as follows: A powder feeding device suitable for an SLM metal 3D printer, comprising: a powder leakage prevention hopper and a first driving unit. The powder leakage prevention hopper includes a stirring bin and a powder feeding bin located below the stirring bin. The stirring bin is used for stirring metal powder. A rotatable powder feeding shaft is concentrically installed in the cylindrical cavity of the powder feeding bin. The first driving unit is connected to the powder feeding shaft to drive the powder feeding shaft to rotate. A plurality of powder feeding grooves are provided on the powder feeding shaft along its axial direction. An inlet is provided at the upper part of the powder feeding bin, and an outlet is provided at the lower part of the powder feeding bin. The inlet and the outlet are located on both sides of the vertical center line of the powder feeding bin. The stirring bin and the powder feeding bin are connected through a first flow channel, and the first flow channel is connected to the inlet.

[0005] Preferably, it further includes a distributor. The distributor is installed at the bottom of the powder leakage prevention hopper. A second flow channel connecting the distributor and the powder feeding bin is provided inside the lower part of the powder leakage prevention hopper, and the upper part of the second flow channel is connected to the outlet. A third flow channel and a fourth flow channel are provided inside the distributor. The metal powder flowing out of the second flow channel of the powder feeding bin is quantitatively distributed in the third flow channel and the fourth flow channel.

[0006] Preferably, both the third flow channel and the fourth flow channel include a plurality of blanking pipes. The blanking pipes of the third flow channel and the blanking pipes of the fourth flow channel are evenly spaced along the axial direction of the powder feeding shaft and are connected to the second flow channel.

[0007] Preferably, the second flow channel is tangent to the powder supply bin.

[0008] Preferably, the first flow channel and the second flow channel are vertical flow channels.

[0009] Preferably, a stirring shaft is installed in the stirring bin, the stirring shaft is connected to the second driving unit, and the second driving unit is used to drive the stirring shaft to rotate.

[0010] Preferably, a stirring shaft is installed in the stirring bin, and the first driving unit drives the stirring shaft to rotate.

[0011] Preferably, the first driving unit includes a driving motor, a reducer, a universal coupling, a first synchronous pulley, a second synchronous pulley and a synchronous belt. The output shaft of the driving motor is connected to the input end of the reducer, and the output end of the reducer is connected to one end of the stirring shaft through the universal coupling. The first synchronous pulley is sleeved on the other end of the stirring shaft, the second synchronous pulley is sleeved on one end of the powder supply shaft, and the first synchronous pulley is connected to the second synchronous pulley through the synchronous belt.

[0012] Preferably, a plurality of stirring rods are arranged on the stirring shaft, a toothed strip is arranged on the inner upper part of the stirring bin, and the stirring rods are located in the gaps between the adjacent toothed strips to form a stirring pair.

[0013] Preferably, a powder storage bin is further included. The powder storage bin is installed above the powder leakage prevention and blanking device, and the powder storage bin is communicated with the stirring bin.

[0014] Preferably, the lateral cross-section of the lower part of the powder storage bin is trapezoidal, and the powder converges to the bottom of the powder storage bin and falls into the stirring bin.

[0015] Due to the adoption of the above technical solutions, the present invention has the following advantages and positive effects compared with the prior art: The powder supply device provided by the present invention divides the powder leakage prevention hopper into two independent chambers, namely a stirring chamber and a powder supply chamber. The stirring chamber and the powder supply chamber are connected through a first flow channel. The metal powder is stirred in the stirring chamber to prevent the metal powder from caking and sticking. The interior of the powder supply chamber is a cylindrical chamber, and a powder supply shaft is fitted and installed in the cylindrical chamber. Powder grooves are provided on the powder supply shaft along its axial direction, and a fixed amount of metal powder can be loaded into each powder groove. The first driving unit drives the powder supply shaft to rotate. When each powder groove meets the powder outlet, the same amount of metal powder can flow out from the powder supply chamber. Then, the powder supply shaft rotates a fixed number of turns according to the powder supply amount to complete the powder supply drive. Since the powder inlet and the powder outlet of the powder supply chamber are distributed on both sides of the vertical center of the powder supply chamber, that is, the powder inlet is not the highest point of the powder supply chamber, and the powder outlet is not the lowest point of the powder supply chamber, it can prevent the powder in the powder supply chamber from leaking onto the powder spreading device during the powder supply process. Therefore, the powder supply device of the present invention can provide loose, uniform and quantitative powder for the printing device, and can prevent powder leakage during the powder supply process. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 FIG. is an overall external view of the powder supply device applicable to an SLM metal 3D printer according to an embodiment of the present invention; Figure 2 FIG. is a side view of the powder supply device applicable to an SLM metal 3D printer according to an embodiment of the present invention; Figure 3 FIG. is a sectional view of the front view of the powder supply device applicable to an SLM metal 3D printer according to an embodiment of the present invention; Figure 4 FIG. is a side sectional view of the powder supply device applicable to an SLM metal 3D printer according to an embodiment of the present invention.

[0017] DESCRIPTION OF THE REFERENCE NUMERALS: 1, powder storage bin; 2, stirring shaft; 21, stirring rod; 3, toothed bar; 4, powder supply shaft; 41, powder groove; 5, first driving unit; 51, servo motor; 52, speed reducer; 53, universal coupling; 54, second synchronous pulley; 55, first synchronous pulley; 56, synchronous belt; 57, bearing; 6, powder leakage prevention hopper; 61, stirring chamber; 62, powder supply chamber; 7, distributor; 8, first flow channel; 9, second flow channel; 10, third flow channel; 11 - fourth flow channel. DETAILED DESCRIPTION OF THE INVENTION

[0018] The following further describes in detail a powder supply device applicable to an SLM metal 3D printer proposed by the present invention with reference to the accompanying drawings and specific embodiments. According to the following description, the advantages and features of the present invention will be clearer.

[0019] Refer to Figure 1, A powder feeding device applicable to an SLM metal 3D printer, comprising: a powder leakage prevention and blanking device 6 and a first driving unit 5. The powder leakage prevention and blanking device 6 includes a stirring bin 61 and a powder feeding bin 62 located below the stirring bin 61. The stirring bin 61 is used for stirring metal powder. A rotatable powder feeding shaft 4 is concentrically installed in the cylindrical cavity of the powder feeding bin 62. The first driving unit 5 is connected to the powder feeding shaft 4 and is used to drive the powder feeding shaft 4 to rotate. A plurality of powder feeding grooves 41 are axially formed on the powder feeding shaft 4. An inlet powder port is arranged at the upper part of the powder feeding bin 62, and an outlet powder port is arranged at the lower part of the powder feeding bin 62. The inlet powder port and the outlet powder port are located on both sides of the vertical center line of the powder feeding bin 62. The stirring bin 61 and the powder feeding bin 62 are communicated through a first flow channel 8, and the first flow channel 8 is communicated with the inlet powder port.

[0020] In the powder feeding device of this embodiment, the powder leakage prevention and blanking device 6 is divided into two independent chambers, namely a stirring bin 61 and a powder feeding bin 62. The stirring bin 61 and the powder feeding bin 62 are communicated through a first flow channel 8. The metal powder is stirred in the stirring bin 61 to prevent the metal powder from caking and sticking. The interior of the powder feeding bin 62 is a cylindrical chamber, and the powder feeding shaft 4 is fitted and installed in the cylindrical chamber. Powder grooves 41 are axially formed on the powder feeding shaft 4. Each powder groove 41 can be filled with a fixed amount of metal powder. The first driving unit 5 drives the powder feeding shaft 4 to rotate. When each powder groove 41 meets the outlet powder port, the same amount of metal powder can flow out from the powder feeding bin 62, and then the powder feeding shaft 4 rotates a fixed number of turns according to the powder feeding amount to complete the powder feeding drive.

[0021] Since the powder feeding shaft 4 needs to rotate in the powder feeding bin 62, it is impossible for the powder feeding shaft 4 to be in close contact with the wall of the powder feeding bin 62. If the inlet powder port and the outlet powder port are on the vertical center line of the powder feeding bin 62, and because the particle size of the metal powder is small and the density is large, and during the printing process, the inside of the powder feeding bin 62 is under positive pressure, even when the powder groove 41 of the powder feeding shaft 4 does not coincide with the outlet powder port, the metal powder is very likely to pass through the gap between the powder feeding shaft 4 and the powder feeding bin 62 from the inlet powder port and leak from the outlet powder port. In this embodiment, the inlet powder port and the outlet powder port are arranged on both sides of the vertical center line of the powder feeding bin 62, that is, the inlet powder port is not the highest point of the powder feeding bin 62, and the outlet powder port is not the lowest point of the powder feeding bin 62. Therefore, the metal powder can enter the powder groove 41 of the powder feeding shaft 4 through the first channel. In this embodiment, since the outlet powder port is not the lowest point of the powder feeding bin 62 and the outlet powder port is obliquely above the lowest point, even if the metal powder has a large density or there is a certain air pressure in the powder feeding bin 62, the metal powder will not leak.

[0022] Further, during the powder feeding process, there is also a need for two-way powder spreading, so it is necessary to quantitatively divide the powder. Therefore, in some preferred embodiments, the powder feeding device further includes a distributor 7. The distributor 7 is installed at the bottom of the powder leakage prevention hopper 6. A second flow channel 9 connecting the distributor 7 and the powder feeding bin 62 is provided inside the lower part of the powder leakage prevention hopper 6. The upper part of the second flow channel 9 is connected to the powder outlet. A third flow channel 10 and a fourth flow channel 11 are provided inside the distributor 7. The metal powder flowing out of the second flow channel 9 of the powder feeding bin 62 is quantitatively distributed between the third flow channel 10 and the fourth flow channel 11.

[0023] Preferably, both the third flow channel 10 and the fourth flow channel 11 include a plurality of uniformly arranged blanking pipes. The blanking pipes of the third flow channel 10 and the blanking pipes of the fourth flow channel 11 are uniformly spaced along the axial direction of the powder feeding shaft 4 and are connected to the second flow channel 9. In this way, the metal powder flowing out of the second flow channel 9 evenly enters each blanking pipe. Furthermore, the metal powder in the third flow channel 10 and the fourth flow channel 11 is quantitatively distributed and then flows out of the distributor 7 along their respective blanking pipes, thus realizing quantitative diversion. If the number of blanking pipes in the third flow channel 10 and the fourth flow channel 11 is the same, an average distribution is achieved. If different amounts of metal powder need to be distributed in the third flow channel 10 and the fourth flow channel 11, the number of blanking pipes in the third flow channel 10 and the fourth flow channel 11 can be changed accordingly.

[0024] In some preferred embodiments, the second flow channel 9 is tangent to the powder feeding bin 62, and the anti-leakage effect is better.

[0025] Further, the first flow channel 8 and the second flow channel 9 are vertical flow channels.

[0026] In some preferred embodiments, stirring of the metal powder in the stirring bin 61 is achieved by installing a stirring shaft 2 in the stirring bin 61. Both ends of the stirring shaft 2 are connected to the stirring bin 61 through bearings 57. The stirring shaft 2 passes through the stirring bin 61 and is connected to a second driving unit outside. The second driving unit is used to drive the stirring shaft 2 to rotate.

[0027] Since the stirring shaft 2 is driven to rotate by the second driving unit and the powder feeding shaft 4 is driven to rotate by the first driving unit 5, preferably, the stirring shaft 2 and the powder feeding shaft 4 can share the same first driving unit 5. The first driving unit 5 includes a driving motor, a reducer, a universal coupling 53, a first synchronous pulley 55, a second synchronous pulley 54, and a synchronous belt 56. The output shaft of the driving motor is connected to the input end of the reducer. The output end of the reducer is connected to one end of the stirring shaft 2 through the universal coupling 53. The first synchronous pulley 55 is sleeved on the other end of the stirring shaft 2. The second synchronous pulley 54 is sleeved on one end of the powder feeding shaft 4. The first synchronous pulley 55 and the second synchronous pulley 54 are connected by the synchronous belt 56.

[0028] With the above-mentioned arrangement of the driving unit 5, the driving motor generates a driving torque which is transmitted through the speed reducer 52 and the universal coupling 53 to the stirring shaft 2 for rotation. At the same time, the first synchronous pulley 55 connected to the other end of the stirring shaft 2 drives the second synchronous pulley 54 to rotate through the synchronous belt 56. The second synchronous pulley 54 is connected to the powder supply shaft 4, and the powder supply shaft 4 rotates a fixed number of turns according to the powder supply amount to complete the powder supply drive.

[0029] To enhance the stirring effect, multiple stirring rods 21 are provided on the stirring shaft 2, and a toothed bar 3 is provided inside the stirring chamber 61. The stirring rods 21 are located in the gaps between adjacent toothed bars 3 to form a stirring pair, increasing the disturbance of the metal powder and strengthening the stirring effect.

[0030] In some embodiments, the powder supply device further includes a powder storage bin 1, which is installed above the powder leakage prevention and blanking device 6, and the powder storage bin 1 is communicated with the stirring chamber 61.

[0031] Preferably, the lateral cross-section of the lower part of the powder storage bin 1 is trapezoidal, and the powder converges to the bottom of the powder storage bin 1 and falls into the stirring chamber 61.

[0032] The powder supply device of this embodiment vertically installs the powder storage bin, the stirring chamber, the powder supply bin and the distributor together, which can not only realize the function of stirring metal powder and prevent powder leakage, but also realize the function of bidirectional quantitative powder supply. The design is compact, making the device applicable to 3D printing equipment.

[0033] The above has described in detail the embodiments of the present invention in conjunction with the accompanying drawings. However, the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, provided that these changes fall within the scope of the claims of the present invention and their equivalent technologies, they still fall within the protection scope of the present invention.

Claims

1. A powder supply device suitable for an SLM metal 3D printer, characterized in that: include: The anti-leakage powder feeder and the first driving unit, the anti-leakage powder feeder comprises a mixing bin and a powder supply bin located below the mixing bin, The stirring bin is used to stir metal powder. A rotatable powder supply shaft is coaxially installed in the cylindrical cavity of the powder supply bin. The first driving unit is connected to the powder supply shaft and is used to drive the powder supply shaft to rotate. A plurality of powder supply grooves are provided on the powder supply shaft along the axial direction of the powder supply shaft. A powder inlet is arranged at the upper part of the powder supply bin, and a powder outlet is arranged at the lower part of the powder supply bin, and the powder inlet and the powder outlet are located on both sides of the vertical center line of the powder supply bin; The stirring bin and the powder supply bin are communicated with each other through a first flow channel, and the first flow channel is communicated with the powder inlet.

2. The powder supply device suitable for SLM metal 3D printer according to claim 1, characterized in that: It also includes a distributor, which is installed at the bottom of the anti-leakage powder dropper, and a second flow channel connecting the distributor and the powder supply bin is arranged in the lower part of the anti-leakage powder dropper; A third flow channel and a fourth flow channel are arranged inside the distributor, and the metal powder flowing out of the second flow channel of the powder supply bin is quantitatively distributed in the third flow channel and the fourth flow channel.

3. The powder supply device suitable for SLM metal 3D printer according to claim 2, characterized in that: The third flow channel and the fourth flow channel each include a plurality of drop tubes. The drop tubes of the third flow channel and the drop tubes of the fourth flow channel are evenly spaced along the axial direction of the powder supply shaft and are communicated with the second flow channel.

4. The powder supply device for SLM metal 3D printer according to claim 2, characterized in that: The second flow channel is tangent to the powder supply bin.

5. The powder supply device for SLM metal 3D printer according to claim 4, characterized in that: The first flow channel and the second flow channel are vertical flow channels.

6. The powder supply device for SLM metal 3D printer according to claim 1, characterized in that: A stirring shaft is installed in the stirring chamber, and the stirring shaft is connected to a second driving unit, and the second driving unit is used to drive the stirring shaft to rotate.

7. The powder supply device for SLM metal 3D printer according to claim 1, characterized in that: A stirring shaft is installed in the stirring chamber, and the first driving unit drives the stirring shaft to rotate.

8. The powder supply device for SLM metal 3D printer according to claim 7, characterized in that: The first driving unit includes a driving motor, a reducer, a universal coupling, a first synchronous wheel, a second synchronous wheel and a synchronous belt. The output shaft of the driving motor is connected to the input end of the reducer, and the output end of the reducer is connected to one end of the stirring shaft through the universal coupling. The first synchronous wheel is sleeved on the other end of the stirring shaft, and the second synchronous wheel is sleeved on one end of the powder supply shaft. The first synchronous wheel and the second synchronous wheel are connected by a synchronous belt.

9. The powder supply device for SLM metal 3D printer according to claim 6 or 7, characterized in that: A plurality of stirring rods are arranged on the stirring shaft, and toothed bars are arranged inside the stirring chamber. The stirring rods are located in the gaps between adjacent toothed bars to form a stirring pair.

10. The powder supply device for SLM metal 3D printer according to claim 1, characterized in that: It also includes a powder storage bin, which is installed on the upper part of the anti-leakage powder dropper, and the powder storage bin is communicated with the stirring bin.

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