Feeding devices and powder layup path planning methods for metal additive manufacturing

Abstract

This invention provides a feeding device and powder layup path planning method for metal additive manufacturing, relating to the field of additive manufacturing technology. It addresses the technical problems of low precision and efficiency in existing technologies that use nozzles of fixed diameters to lay powder line by line according to a planned path. The method includes the following steps: laying one layer using a large-diameter nozzle along a path, wherein each layer has two or more powder-laying areas with different powder materials; reserving areas for powder laying between adjacent powder-laying areas when using the large-diameter nozzle; and then replacing the nozzle with a small-diameter nozzle to lay the reserved areas according to the path. The path planning strategy of this invention is to first divide most of the area using a wider powder path, lay powder using a large-diameter nozzle, and then fill the more detailed areas not covered by the large-diameter nozzle with a narrower powder path, achieving both high efficiency and high precision.

Description

Technical Field

[0001] This invention relates to the field of additive manufacturing technology, and in particular to a feeding device and powder layup path planning method for metal additive manufacturing. Background Technology

[0002] With the development of additive manufacturing, the demand for multi-material printing is becoming increasingly apparent. Currently, multi-material printing is mainly carried out using arc additive metallurgy and laser deposition additive manufacturing technologies. However, the printed components using these technologies have relatively low precision and require secondary processing after completion. Powder-spread selective laser melting (SLM) technology is characterized by high precision and less post-processing requirements, but its development in multi-material additive forming has been slower.

[0003] The applicant has discovered that the prior art has at least the following technical problems:

[0004] Existing multi-material printing using laser selective melting technology often employs multiple nozzles for selective powder spreading and suction. (See...) Figure 1 When laying material A, nozzle A lays the powder area of ​​material A one row at a time along the designed path, and then nozzle B is switched to lay the powder area of ​​material B one row at a time along the designed path, and so on. The problem is that using nozzles of fixed diameter to lay the powder row by row according to the path plan is time-consuming, inefficient, results in too many powder laying areas, and poor overall powder uniformity. Summary of the Invention

[0005] The purpose of this invention is to provide a feeding device and a powder laying path planning method for metal additive manufacturing, so as to solve the technical problems of long time consumption and low efficiency in the prior art, which uses nozzles of fixed diameter to lay powder line by line according to the path planning. 。 The preferred technical solutions among the many technical solutions provided by this invention can produce a variety of technical effects, which are described in detail below.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] The present invention provides a powder laying path planning method, comprising the following: laying a layer according to a path using a large-diameter nozzle, wherein the layer has two or more powder laying areas and the powder material of each powder laying area is different, and reserving a powder-to-lay area between adjacent powder laying areas when laying with a large-diameter nozzle; and laying the reserved powder-to-lay area according to the path using a small-diameter nozzle.

[0008] Furthermore, the reserved area to be padded between two adjacent powder-spreading areas is divided into two reserved partitions. The materials used for the two reserved partitions are different, and the two reserved partitions are located on opposite sides.

[0009] This invention provides a feeding device for metal additive manufacturing that is used in conjunction with the powder layup path planning method described above. The device comprises a material hopper, a nozzle support, nozzles, and a nozzle driving device. Two or more nozzles are mounted on the nozzle support. The driving device is connected to the nozzle support. Nozzle mating positions are formed on the material hopper. At least two nozzles have different orifice sizes. The driving device can drive the nozzle support to switch between different nozzles mating with the nozzle mating positions.

[0010] Furthermore, the nozzle support has a ring-shaped structure, the nozzles are distributed on the lower side of the nozzle support in the circumferential direction, the upper side of the nozzle support has through holes and each nozzle has a corresponding through hole connected to the other, the bottom end of the material barrel has a groove to form the nozzle mating position, and the nozzle support passes through the nozzle mating position.

[0011] Furthermore, the nozzle is annular, and the slot is U-shaped.

[0012] Furthermore, the nozzle driving device is supported on one side of the material barrel by a fixing frame, and the rotating shaft of the nozzle driving device is connected to the nozzle bracket through a connecting frame, so that the nozzle driving device can drive the nozzle bracket to rotate.

[0013] Furthermore, an extrusion screw is provided inside the material barrel, and the extrusion screw is connected to a screw motor located at the top of the material barrel. A powder feeding channel is connected to the upper end of the material barrel, and a vacuum suction pipe is provided near the lower end of the material barrel.

[0014] The present invention provides a printing device, including the aforementioned feeding device for metal additive manufacturing.

[0015] The preferred technical solution of the present invention can produce the following technical effects: The path planning strategy provided by the present invention is to first divide most of the area with a wider powder channel, lay powder with a large-diameter nozzle, and then fill the more detailed areas not covered by the large-diameter nozzle with a narrower powder channel, which can achieve the dual effect of high efficiency and high precision. Attached Figure Description

[0016] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0017] Figure 1 This is a schematic diagram of existing traditional path planning methods;

[0018] Figure 2 This is a flowchart of the powder laying path planning method provided by the present invention;

[0019] Figure 3 This is a schematic diagram of the path planning method provided by the present invention;

[0020] Figure 4 This is a schematic diagram of the feeding device for metal additive manufacturing provided by the present invention;

[0021] Figure 5 This is a schematic diagram of the material hopper of the feeding device for metal additive manufacturing provided by the present invention;

[0022] Figure 6 This is a schematic diagram of the nozzle and nozzle holder provided by the present invention;

[0023] Figure 7 This is a schematic diagram of the nozzle and nozzle holder provided by the present invention.

[0024] In the diagram: 1. Material bucket; 2. Nozzle bracket; 3. Nozzle; 4. Nozzle drive device; 5. Nozzle mating position; 6. Fixing frame; 7. Connecting frame; 8. Extrusion screw; 9. Screw motor; 10. Powder feeding channel; 11. Vacuum suction pipe. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be described in detail below. Obviously, the described embodiments are merely some embodiments of this invention, and not all embodiments. Based on the embodiments of this invention, all other implementation methods obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] Existing multi-material printing using laser selective melting technology often employs multiple nozzles for selective powder spreading and suction. (See...) Figure 1 When laying material A, nozzle A lays the powder area of ​​material A one row at a time along the designed path, and then nozzle B is switched to lay the powder area of ​​material B one row at a time along the designed path, and so on. The problem is that using nozzles of fixed diameter to lay the powder row by row according to the path plan is time-consuming, inefficient, results in too many powder laying areas, and poor overall powder uniformity.

[0027] Based on the above questions, see Figures 2-3 This invention provides a powder laying path planning method, including the following:

[0028] A layer is laid along the path using a large-diameter nozzle 3. In this layer, there are two or more powder-laying areas and the powder material for each powder-laying area is different. When laying with a large-diameter nozzle 3, a powder-to-powder area is reserved between adjacent powder-laying areas. When replacing with a small-diameter nozzle 3, the reserved powder-to-powder area is laid along the path.

[0029] The path planning strategy provided by this invention is as follows: First, a wide powder channel is used to divide most of the area, and powder is laid with a large-diameter nozzle. Then, the finer areas not covered by the large-diameter nozzle are filled with a narrower powder channel, which can achieve the dual effect of high efficiency and high precision.

[0030] See Figure 3 The reserved area between two adjacent powder-spreading areas is divided into two reserved zones. The materials used for the reserved zones in the two zones are different, and the two reserved zones are located on the (inner and outer) sides respectively.

[0031] by Figure 3 For example, the powder laying path planning method provided by the present invention is specifically described as follows:

[0032] The area outside the circular dashed line is the powder-spreading area of ​​material A, the area between the circular dashed line and the triangular dashed line is the powder-spreading area of ​​material B, and the area inside the triangular dashed line is the powder-spreading area of ​​material C.

[0033] First, use a wide powder channel, i.e., a large-aperture nozzle, to lay the powder: first, use the large-aperture nozzle to lay the powder in the area where material A is laid, then switch to material B and use the large-aperture nozzle to lay the powder in the area where material B is laid. Leave a reserved area between the areas where material A is laid and the areas where material B is laid. Figure 3 The white areas on either side of the central circular dotted line are reserved areas for powder application. Then, replace with material C and apply the powder to the material C application area using a large-diameter nozzle. Reserve a reserved area for powder application between the material B application areas. Figure 3 The white areas on either side of the dashed triangle in the middle are reserved areas for applying powder.

[0034] Replace with a smaller orifice nozzle and fill the reserved powder-spreading area with a narrower powder channel. See also Figure 3 Outside the circular dashed line, straight lines with arrows are shown, indicating the movement path of the small-diameter nozzle. Replace with material A, and lay material A according to the arrows indicated outside the circular dashed line. Then replace with material B, and lay material B according to the arrows indicated inside the circular dashed line. Outside the triangular dashed line, straight lines with arrows are shown; this area is also covered with material B, i.e., laid according to the arrows indicated outside the triangular dashed line. Then replace with material C, and lay material C according to the arrows indicated inside the triangular dashed line.

[0035] See Figures 4-7The present invention provides a feeding device for metal additive manufacturing that is used in conjunction with a powder layup path planning method. The structure is as follows: it includes a material bucket 1, a nozzle support 2, a nozzle 3, and a nozzle driving device 4. The nozzle support 2 is provided with two or more nozzles 3. The driving device is connected to the nozzle support 2. A nozzle mating position 5 is formed on the material bucket 1. At least two nozzles 3 have different orifice sizes. The driving device can drive the nozzle support 2 to switch between different nozzles 3 and nozzle mating positions 5.

[0036] See Figure 4 This diagram illustrates a feeding device used in metal additive manufacturing. When a larger orifice nozzle needs to be replaced, the control drive mechanism moves the nozzle support 2, causing the larger orifice nozzle 3 to move to the nozzle mating position 5. When powder in the material container 1 is fed downwards, the powder in the material container 1 can be ejected through the larger orifice nozzle 3. When a smaller orifice nozzle needs to be replaced, the control drive mechanism moves the nozzle support 2, causing the smaller orifice nozzle 3 to move to the nozzle mating position 5. When powder in the material container 1 is fed downwards, the powder in the material container 1 can be ejected through the smaller orifice nozzle 3.

[0037] The feeding device for metal additive manufacturing provided by this invention allows for the replacement of nozzles with different orifice diameters as needed, and nozzles with different orifice diameters can lay powder channels of different widths.

[0038] Regarding nozzle holder 2, see Figure 4 , Figures 6-7 The nozzle support 2 has a ring structure. The nozzles 3 are distributed on the lower side of the nozzle support 2 in the circumferential direction. The upper side of the nozzle support 2 has through holes and each nozzle 3 has a corresponding through hole connected to each other. The bottom end of the material barrel 1 has a groove to form a nozzle mating position 5. The nozzle support 2 passes through the nozzle mating position 5.

[0039] Nozzle 3 is annular, and the slot is U-shaped. See also Figure 5 The diagram illustrates the nozzle mating position 5 of the U-shaped groove. The nozzle mating position 5 is provided with an opening that communicates with the inside of the material barrel 1. Figure 4 The diagram illustrates that the nozzle support 2 passes through the nozzle mating position 5. When the nozzle support 2 rotates, different nozzles 3 can be switched to connect to the opening on the nozzle mating position 5.

[0040] The nozzle drive device 4 is supported on one side of the material barrel 1 by the fixing frame 6. The rotating shaft of the nozzle drive device 4 is connected to the nozzle support 2 through the connecting frame 7. The nozzle drive device 4 can drive the nozzle support 2 to rotate. The nozzle drive device 4 is a drive motor. The nozzle drive device 4 can drive the nozzle support 2 to rotate horizontally to switch different nozzles 3 to connect the openings on the nozzle mating position 5.

[0041] Furthermore, an extrusion screw 8 is installed inside the material barrel 1. The extrusion screw 8 is connected to a screw motor 9 located at the top of the material barrel 1. The screw motor 9 can drive the extrusion screw 8 to rotate. A powder feeding channel 10 is connected to the upper end of the material barrel 1, and a vacuum suction pipe 11 is installed near the lower end of the material barrel 1. The extrusion screw 8, the powder feeding channel 10, and the vacuum suction pipe 11 are all existing technologies and will not be described in detail here.

[0042] This invention provides a 3D printing device, including the aforementioned feeding device for metal additive manufacturing. The specific structure of the feeding device for metal additive manufacturing has been described above and will not be repeated here.

[0043] In the description of this invention, it should be noted that, unless otherwise stated, "a plurality of" means two or more; the terms "upper," "lower," "left," "right," "inner," "outer," "front end," "rear end," "head," "tail," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," "third," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0044] In the description of this invention, it should also be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0045] In the description of this specification, the references to terms such as "one embodiment," "some embodiments," "example," "specific example," or "a particular example," etc., indicate that a specific feature, structure, material, or characteristic described in connection with that embodiment or example is included in at least one embodiment or example of this application. In this specification, the illustrative expressions of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the specific features, structures, materials, or characteristics described may be combined in any suitable manner in one or more embodiments or examples.

[0046] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A powder laying path planning method, characterized in that, Includes the following: A layer is laid along the path using a large-aperture nozzle (3). In this layer, there are two or more powder-laying areas and the powder material for each powder-laying area is different. When laying the powder using a large-aperture nozzle (3), a powder-laying area is reserved between adjacent powder-laying areas. Replace the small-diameter nozzle (3) and lay the reserved powder-to-powder area according to the path; The reserved area between two adjacent powder-spreading areas is divided into two reserved zones. The materials used for the two reserved zones are different, and the two reserved zones are located on opposite sides. The feeding device for metal additive manufacturing, used in conjunction with the powder layup path planning method, includes a hopper (1), a nozzle holder (2), a nozzle (3), and a nozzle drive device (4), wherein, Two or more nozzles (3) are provided on the nozzle support (2), the driving device is connected to the nozzle support (2), a nozzle mating position (5) is formed on the material barrel (1), at least two of the nozzles (3) have different orifice sizes, and the driving device can drive the nozzle support (2) to switch different nozzles (3) to mat with the nozzle mating position (5).

2. The powder laying path planning method according to claim 1, characterized in that, The nozzle support (2) has a ring structure. The nozzles (3) are distributed on the lower side of the nozzle support (2) in the circumferential direction. The upper side of the nozzle support (2) has a through hole and each nozzle (3) is connected to the corresponding through hole. The bottom end of the material bucket (1) has a groove to form the nozzle mating position (5). The nozzle support (2) passes through the nozzle mating position (5).

3. The powder laying path planning method according to claim 2, characterized in that, The nozzle (3) is annular, and the slot is a U-shaped slot.

4. The powder laying path planning method according to claim 2, characterized in that, The nozzle drive device (4) is supported on one side of the material bucket (1) by a fixing frame (6). The rotating shaft of the nozzle drive device (4) is connected to the nozzle support (2) through a connecting frame (7). The nozzle drive device (4) can drive the nozzle support (2) to rotate.

5. The powder laying path planning method according to claim 1, characterized in that, The material barrel (1) is provided with an extrusion screw (8), which is connected to a screw motor (9) located at the top of the material barrel (1). The upper end of the material barrel (1) is connected to a powder feeding channel (10), and a vacuum suction pipe (11) is provided near the lower end of the material barrel (1).

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