Additive manufacturing powder mixing device

Abstract

The utility model provides an additive manufacturing powder mixing device. The additive manufacturing powder mixing device comprises a powder feeding mechanism and a static mixer, the number of the powder feeding mechanisms is at least two, and the powder feeding mechanisms are both installed above the peripheral side of the static mixer. The powder feeding mechanism comprises a transfer bin and spiral conveyors, the bottom end of the transfer bin is communicated with conveying ports of the spiral conveyors, and discharging ports of all the spiral conveyors are communicated and then communicated with the static mixer. The problem of labor consumption in an existing powder circulation mode is solved, and the safety risk that heat is generated due to powder collision and friction is avoided; the powder mixing continuity is ensured, the powder mixing efficiency is improved, safety detection is achieved in the whole process, and the powder mixing device is suitable for inflammable and explosive powder scenes.

Description

Technical Field

[0001] The utility model belongs to the technical field of powder mixing devices, and in particular relates to an additive manufacturing powder mixing device. Background Art

[0002] In the metal additive manufacturing industry, metal powder is the commonly used raw material. In order to ensure the consistency of the overall mechanical properties of printed parts, there are also extremely strict requirements on the content of chemical elements in metal powder, particle size and other physical properties. At present, the price of metal powder on the market is relatively high. Parts printing manufacturers often use the same brand of powder A and powder B from different manufacturers or different batches, and the powder particle size and content of certain chemical elements will be different. The difference in metal powder particle size and element content will lead to differences in the performance of additively manufactured parts. In order to ensure the consistency of the overall performance of printed parts, multiple batches of powder need to be evenly mixed to achieve powder C (A+B=C) as a consistent powder.

[0003] The common powder mixing method is to manually add the A and B powders into a sealed canned container with a stirring shaft, and then the canned container rotates, reverses and stirs with the stirring shaft to complete the mixing of the powders. However, this powder mixing method has the following shortcomings:

[0004] 1) It is necessary to manually add powder (canned) and recover the powder after mixing;

[0005] 2) Powder flipping, stirring, friction and collision will generate a lot of heat, and there is a risk of pressure explosion in sealed containers;

[0006] 3) The single powder mixing volume is small, the cycle is long, and the operation is non-continuous.

[0007] 4) For parts with high powder requirements, the single preparation time is longer.

[0008] 5) When the canned powder is turned over or rotated, it is impossible to monitor the atmosphere inside the sealed cavity in real time, such as the powder flow blocking the detection pipeline;

[0009] Based on this, it is necessary to design an additive manufacturing powder mixing device. Utility Model Content

[0010] The technical problem to be solved by the present invention is to provide an additive manufacturing powder mixing device in view of the deficiencies of the above-mentioned prior art, so as to solve the problems raised in the above-mentioned background technology.

[0011] In order to solve the above technical problems, the technical solution adopted by the utility model is: an additive manufacturing powder mixing device, including a powder feeding mechanism and a static mixer; at least two powder feeding mechanisms are provided, and the powder feeding mechanisms are installed above the circumference of the static mixer; the powder feeding mechanism includes a transfer bin and a screw conveyor, the bottom end of the transfer bin is connected to the feeding port of the screw conveyor, and all the discharge ports of the screw conveyors are connected and then connected to the static mixer respectively.

[0012] As a further illustration of the present invention, the powder feeding mechanism is also connected to a feeding device for adding powder into the transfer bin.

[0013] As a further illustration of the present invention, the bottom end of the static mixer is connected to a powder collecting barrel.

[0014] As a further explanation of the utility model, the feeding device includes a cyclone separator installed at the top of the transfer bin and a feed pipe connected to the cyclone separator, a negative pressure generating device is installed on the cyclone separator, and a filter element is provided at the connection between the cyclone separator and the negative pressure generating device to prevent powder from entering the negative pressure generating device.

[0015] As a further description of the present invention, the negative pressure generating device is a vacuum generator or a fan.

[0016] As a further illustration of the present invention, the feeding end of the feeding pipe is connected to a powder placement barrel.

[0017] As a further illustration of the present invention, a level meter is also installed in the cyclone separator.

[0018] As a further illustration of the present invention, a first pneumatic butterfly valve is installed between the cyclone separator and the transfer bin, and a second pneumatic butterfly valve is installed between the static mixer and the powder collection barrel.

[0019] As a further illustration of the present invention, each of the screw conveyors is driven by an independently controlled drive motor.

[0020] As a further illustration of the present invention, the screw conveyor is arranged horizontally, and the screw conveyors corresponding to the powder feeding mechanism are evenly distributed above the static mixer.

[0021] Compared with the prior art, the utility model has the following advantages:

[0022] 1. The utility model solves the manpower consumption in the existing powder circulation mode and saves manpower.

[0023] 2. The utility model avoids the safety risk of heat generation due to powder collision and friction.

[0024] 3. The utility model ensures the continuity of powder mixing, improves the powder mixing efficiency and increases the production capacity.

[0025] 4. This utility model has a full-process safety detection and is suitable for flammable and explosive powder scenarios. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the overall structure of the utility model.

[0027] Description of reference numerals:

[0028] 1-powder feeding mechanism; 11-powder placing barrel; 12-feeding pipe; 13-cyclone separator; 14-negative pressure generating device; 15-filter element; 16-transfer bin; 17-first pneumatic butterfly valve; 18-screw conveyor; 2-static mixer; 3-powder collecting barrel; 4-second pneumatic butterfly valve. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0030] like Figure 1 As shown, the utility model provides a technical solution: an additive manufacturing powder mixing device, comprising a powder feeding mechanism 1 and a static mixer 2;

[0031] At least two powder feeding mechanisms 1 are provided, and both powder feeding mechanisms 1 are installed above the peripheral side of the static mixer 2;

[0032] The powder feeding mechanism 1 includes a transfer bin 16 and a screw conveyor 18. The bottom end of the transfer bin 16 is connected to the feeding port of the screw conveyor 18. The powder feeding mechanism 1 is also connected to a feeding device for adding powder into the transfer bin 16. The feeding device includes a cyclone separator 13 installed at the top of the transfer bin 16 and a feeding pipe 12 connected to the cyclone separator 13. The cyclone separator 13 is installed with a negative pressure generating device 14.

[0033] The negative pressure generating device 14 is a vacuum generator or a fan, and a filter element 15 is provided at the connection between the cyclone separator 13 and the negative pressure generating device 14 to prevent powder from entering the vacuum generator;

[0034] A level meter is also installed in the cyclone separator 13;

[0035] The feeding end of the feeding pipe 12 is connected to a powder placement barrel 11, and the discharge ports of all the screw conveyors 18 are connected and respectively connected to the static mixer 2. The screw conveyors 18 are horizontally arranged, and each of the screw conveyors 18 is driven by an independently controlled drive motor. The screw conveyors 18 corresponding to the powder feeding mechanism 1 are evenly distributed above the static mixer 2.

[0036] In this embodiment, the bottom end of the static mixer 2 is connected to a powder collecting barrel 3. A first pneumatic butterfly valve 17 is installed between the cyclone separator 13 and the transfer bin 16, and a second pneumatic butterfly valve 4 is installed between the static mixer 2 and the powder collecting barrel 3.

[0037] During specific use, two powder feeding mechanisms 1 are provided, symmetrically arranged above both sides of the static mixer 2 , the discharge ports of the two screw conveyors 18 are connected, and the port connected to the static mixer 2 is located directly above the static mixer 2 .

[0038] In the primary powder processing stage, the feed pipe 12 is connected to the butterfly valve port at the bottom of the powder placing barrel 11, and the powder collecting barrel 3 is connected to the bottom of the static mixer 2 to ensure that the system pipeline connection is complete;

[0039] Then close the first pneumatic butterfly valve 17, the vacuum generator starts to work, and the powders in the two powder placing barrels 11 enter the cyclone separator 13 through the corresponding feeding pipes 12 under the action of vacuum. The powders are blocked by the filter element 15 and fall into the bottom of the cyclone separator 13, and the gas is discharged from the top;

[0040] When the level meter detects that the cyclone separator 13 is full of powder, the powder feeding work stops, the first pneumatic butterfly valve 17 is opened and the second pneumatic butterfly valve 4 is closed, and the powder falls into the transfer bin 16 by its own weight. The two driving motors respectively control the two screw conveyors 18 to start working at the same or different speeds. The ratio of different powders in the mixed powder is adjusted by adjusting the speed, and the different (batches) of powders in the two transfer bins 16 are horizontally transmitted at a constant speed. The different (batches) of powders are evenly collected at the connecting port in the middle position and fall into the static mixer 2. The powders in the two transfer bins 16 are cross-mixed by the static mixer 2 to achieve a uniform mixing state. The mixed powder opens the second pneumatic butterfly valve 4 and is collected in the powder collection barrel 3 to complete the powder mixing operation.

[0041] At the same time, three or four different (batches) of powders can also be mixed. The mixing process of the above two different (batches) of powders is only for explaining the mixing process, and does not limit the present application to mixing only two different (batches) of powders.

[0042] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0043] Although the embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. An additive manufacturing powder mixing device, characterized in that: It comprises a powder feeding mechanism (1) and a static mixer (2); At least two powder feeding mechanisms (1) are provided, and both powder feeding mechanisms (1) are installed above the peripheral side of the static mixer (2); The powder feeding mechanism (1) comprises a transfer bin (16) and a screw conveyor (18), the bottom end of the transfer bin (16) is connected to the feeding port of the screw conveyor (18), and all the discharge ports of the screw conveyors (18) are connected and then respectively connected to the static mixer (2).

2. The additive manufacturing powder mixing device according to claim 1, characterized in that: The powder feeding mechanism (1) is also connected to a feeding device for adding powder into the transfer bin (16).

3. An additive manufacturing powder mixing device according to claim 1 or 2, characterized in that: The bottom end of the static mixer (2) is connected to a powder collecting barrel (3).

4. The additive manufacturing powder mixing device according to claim 2, characterized in that: The feeding device comprises a cyclone separator (13) installed at the top of a transfer bin (16) and a feeding pipe (12) connected to the cyclone separator (13); a negative pressure generating device (14) is installed on the cyclone separator (13); and a filter element (15) is provided at the connection between the cyclone separator (13) and the negative pressure generating device (14) to prevent powder from entering the negative pressure generating device (14).

5. The additive manufacturing powder mixing device according to claim 4, characterized in that: The negative pressure generating device (14) is a vacuum generator or a fan.

6. The additive manufacturing powder mixing device according to claim 4, characterized in that: The feeding end of the feeding pipe (12) is connected to a powder placement barrel (11).

7. The additive manufacturing powder mixing device according to claim 4, characterized in that: A level meter is also installed in the cyclone separator (13).

8. The additive manufacturing powder mixing device according to claim 4, characterized in that: A first pneumatic butterfly valve (17) is installed between the cyclone separator (13) and the transfer bin (16), and a second pneumatic butterfly valve (4) is installed between the static mixer (2) and the powder collection barrel (3).

9. The additive manufacturing powder mixing device according to claim 1, characterized in that: Each of the screw conveyors (18) is driven by an independently controlled drive motor.

10. The additive manufacturing powder mixing device according to claim 1, characterized in that: The screw conveyor (18) is arranged horizontally, and the screw conveyors (18) corresponding to the powder feeding mechanism (1) are evenly distributed above the static mixer (2).

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