CN219188625U - Powder circulation powder paving device and 3D printing equipment - Google Patents

Abstract

The utility model provides a powder circulation powder spreading device and 3D printing equipment, which comprises a gas conveying part for conveying inert gas into at least one gas flow channel; the powder circulation shell is arranged at a position which can at least correspond to a powder overflow area; the powder spreading part is arranged between the powder circulation shell and the powder overflowing area and used for spreading the scattered powder so as to uniformly spread the powder on a forming platform; and the gas spraying part is arranged on one side of the powder circulating shell and/or the powder spreading part, which is close to the powder overflowing area, so as to spray inert gas in the gas flow passage into the wrapping space of the powder circulating shell, wherein the gas flow passage is arranged in the shell layer of the powder circulating shell and/or the powder spreading part. The utility model can make the powder be scattered, namely, change the cluster phenomenon, become looser, and be favorable for better realizing uniform powder spreading on a forming platform.

Description

Powder circulation powder paving device and 3D printing equipment

Technical Field

The utility model relates to the field of 3D printing, in particular to a powder circulation powder paving device and 3D printing equipment.

Background

When 3D printing is performed to construct a part, the part is often planed into a plurality of two-dimensional plane structures, and then the part is finally formed through layer-by-layer printing. Particularly for the powder laying sintering/melting technology, a layer of metal powder/nonmetal powder is laid layer by layer, then the laid layer of metal powder is subjected to zone selection sintering/melting through a heat source (usually laser), so that the structure of the part on the layer is constructed, and the construction of the part is finally completed through the layer-by-layer powder laying and sintering/melting.

In the current powder spreading 3D printing technology field, powder is generally required to have good flowability and proper particle size so as to ensure the integrity and uniformity of powder spreading. Therefore, powder particles of the paving material are generally required to have good sphericity and uniform particle size, and the powder is paved on a forming platform through a powder paving device, but the powder paved can be uneven due to the actions of powder agglomeration and the like, so that the formed parts have defects and the like.

Disclosure of Invention

In order to reduce powder agglomeration so that the laid powder is more uniform, one aspect of the present utility model provides a powder circulation powder laying apparatus for a 3D printing device, comprising: a gas delivery section for delivering the prepared and/or stored inert gas into at least one gas flow passage; the powder circulation shell is arranged at a position which can at least correspond to a powder overflow area, wherein the inert gas is conveyed into a wrapping space of the powder circulation shell through the gas flow channel so as to disturb powder at the powder overflow area corresponding to the powder circulation shell, and the powder is circulated in the wrapping space of the powder circulation shell under the disturbance of the inert gas so as to be dispersed; the powder spreading part is arranged between the powder circulation shell and the powder overflowing area and is used for spreading the scattered powder so as to uniformly spread the powder on a forming platform; the gas spraying part is arranged at one side of the powder circulation shell and/or the powder spreading part, which is close to the powder overflow area, and is used for spraying inert gas in the gas flow channel into the wrapping space of the powder circulation shell; wherein the gas flow passage is arranged in the shell layer of the powder circulation shell and/or the powder paving part.

Preferably, the powder overflow area is formed at a powder outlet of at least one powder bin.

Preferably, the gas delivery part comprises a gas delivery pipeline, wherein the gas delivery pipeline is communicated with the gas flow passage, and the gas delivery part is used for delivering the prepared and/or stored inert gas into the gas flow passage through the gas delivery pipeline.

Preferably, the gas spraying part is a nozzle with adjustable spraying direction.

Preferably, the powder circulation housing is movably disposed above the powder discharge area and the forming table to reciprocate above the powder discharge area and the forming table.

Preferably, the powder spreading part is fixedly arranged at one end of the powder circulation shell facing the powder overflow area and/or the forming platform so as to synchronously move under the drive of the powder circulation shell.

Preferably, the gas flow passage is composed of a first gas flow passage and a second gas flow passage; wherein the first gas flow passage is arranged in a shell layer of the powder circulation shell; the second gas flow passage is arranged in the powder spreading part, wherein the second gas flow passage is communicated with the first gas flow passage, the inert gas is conveyed into the second gas flow passage through the first gas flow passage, and then is sprayed into the wrapping space of the powder circulation shell through the gas spraying part arranged on one side of the powder spreading part, which is close to the powder overflow area.

Preferably, the powder overflow areas are arranged at two positions and are respectively arranged at two sides of the forming platform; wherein the powder circulation shell can reciprocate on two powder overflow areas and corresponding positions of the forming platform to perform bidirectional powder paving.

Preferably, the powder circulation powder spreading device further comprises a heating device, which is arranged in the wrapping space of the powder circulation shell and used for preheating the powder in the wrapping space of the powder circulation shell.

Preferably, the powder circulation powder spreading device further comprises: and a plasma generating part arranged between the gas conveying part and the gas flow channel and used for emitting plasma into the flow path of the inert gas so as to enable the inert gas to have charged particles.

In order to reduce agglomeration of powder so that the laid powder is more uniform, one aspect of the present utility model provides a 3D printing apparatus including a structure in which the powder circulation powder laying device described above is mounted to the 3D printing apparatus.

According to the utility model, when the inert gas is conveyed into the wrapping space of the powder circulation shell through the gas flow channel, the powder at the powder overflow area corresponding to the powder circulation shell can be disturbed, so that the powder can circularly move in the wrapping space of the powder circulation shell under the disturbance of the inert gas, and further, the powder is scattered, i.e. the phenomenon of clusters is changed, and the powder becomes looser, thereby being beneficial to better realizing uniform powder spreading on a forming platform.

In addition, the inert gas can flow along the longitudinal direction of the powder circulation shell by arranging the gas flow channels in the shell layer and/or the powder spreading part of the powder circulation shell, so that the inert gas in the gas flow channels can be conveniently sprayed to all heights in the wrapping space of the powder circulation shell by the gas spraying part arranged on one side of the powder circulation shell and/or the powder spreading part close to the powder overflow area, and the powder is more fully dispersed.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the following description will briefly explain the drawings used in the embodiments or the description of the prior art, and it is obvious that the drawings in the following description are only embodiments of the present application, and other drawings can be obtained according to the provided drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of a powder circulation powder spreading device in a powder static state according to an embodiment of the present utility model;

FIG. 2 is a schematic view of a powder circulation powder spreading device in a powder circulation state according to an embodiment of the present utility model;

FIG. 3 is a schematic view showing a structure of a powder circulating laying device outside a discard gas conveying unit according to an embodiment of the present utility model;

fig. 4 and 5 are schematic structural views respectively showing a powder circulation powder spreading device according to an embodiment of the present utility model;

FIG. 6 is a schematic view showing a state change of a powder spreading portion according to an embodiment of the present utility model;

FIG. 7 is a schematic view showing a state change of a powder circulation housing and a powder spreading portion according to an embodiment of the present utility model;

FIG. 8 is a schematic diagram of a 3D printing apparatus with a single powder bin according to an embodiment of the present utility model;

FIG. 9 is a schematic diagram of a dual-bin 3D printing apparatus according to one embodiment of the present utility model;

fig. 10 and 11 are schematic diagrams showing distribution of gas channels according to an embodiment of the utility model.

Detailed Description

Embodiments of the present utility model are described in detail below, examples of which are illustrated in the accompanying drawings, wherein like or similar reference numerals refer to like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are illustrative and intended to explain the present utility model and should not be construed as limiting the utility model.

According to one aspect of the present utility model, a powder circulation powder spreading device is provided for a 3D printing apparatus, i.e. it may be configured as part of a 3D printing apparatus, the 3D printing apparatus described herein preferably being of the type of 3D printing using a laser beam/electron beam as an energy source, such as selective laser sintering (Selective laser sintering, SLS), selective laser melting (Selective laser melting, SLM) or the like. Powder bed-based 3D printing techniques all require pre-laying of powder, laser scanning, melting of the material, solidification of loose powder together, layer-by-layer scanning, layer-by-layer laying of powder, and sinking of a retractable platform, and finally obtaining of a powder-wrapped solid.

The 3D printing equipment is composed of at least a mechanical unit, an optical path unit, a computer control system and the like. The powder circulation powder spreading device of the present utility model is preferably used as part of a mechanical unit, but it may be used alone as a part juxtaposed with the mechanical unit, the light path unit and the computer control system. In a specific spatial arrangement form, the optical path unit may be arranged above the mechanical unit, or may be set based on the core utility model point taught in the present application according to an actual structural design. In the control logic, the control of the mechanical unit and the light path unit is realized by a computer control system, i.e. the control of the electrostatic device of the utility model is preferably realized by a computer control system.

The powder circulation powder spreading device of the utility model needs to be in an action relation with other parts of the 3D printing equipment, especially the mechanical unit when in use, and the constitution of the mechanical unit of the 3D printing equipment is described herein.

Referring to fig. 8, in some embodiments, after omitting the powder circulation powder spreading device of the present utility model, the mechanical unit of the 3D printing apparatus is composed of at least the forming hopper 24, the powder hopper 21, the forming elevating device 25, the powder supplying elevating device 26, and the like. Wherein the forming bin 24 is used for forming the work piece 28, i.e. the forming work piece 28 completes the final construction in the forming bin 24; the distance that the forming bin 24 descends each time is the layer thickness; after the forming work 28 is built, the forming bin 24 is raised to facilitate removal of the built forming work 28 and preparation for the next build. The lifting of the forming bin 24 is driven by a forming lifting device 25. The powder bin 21 is provided at one side of the forming bin 24 for supplying powder material to the forming bin 24. The powder hopper 21 is driven to rise and fall by a powder supply lifting device 26. The powder described herein refers to a material to be processed, which is used in a powder state. For example, the powder may consist essentially of a material made of metal or polymer. During construction, the powder is laid layer by layer over the forming bin 24, i.e. over the forming table 23, thereby forming a powder bed 29 over the forming table 23 in the forming bin 24.

Referring to fig. 9, in some embodiments, the mechanical unit of the 3D printing apparatus further has a powder hopper 22 and a powder supply lifting device 27 in addition to the above disclosed structure. Wherein the powder bin 22 is disposed on the other side of the forming bin 24 and also serves to provide powder material to the forming bin 24. The elevation of the powder hopper 22 is driven by a powder supply elevation device 27. It should be understood that the mechanical unit of the 3D printing apparatus may have only a single powder bin structure as shown in fig. 8, or may have a double powder bin structure as shown in fig. 9; when using the single-bin configuration shown in fig. 8, the bin 21 may be disposed either to the left of the forming bin 24 or to the right of the forming bin; when the double-bin structure shown in fig. 9 is used, the bins 21 and 22 may also be alternately interchanged as a bin for temporary powder supply or collection of excess material.

Referring to fig. 1 and 2, in some embodiments, the powder circulation powder spreading device of the present utility model is composed of at least a gas conveying part 10, a powder circulation casing 11, powder spreading parts 12 and 13, and gas jetting parts 14-a and 14-b.

Wherein the gas delivery section 10 is configured to deliver the inert gas prepared and/or stored into the gas flow channel.

In some embodiments, as shown in fig. 10, the gas flow passage is designated as a first gas flow passage 112, which is provided only within the shell layer 111 of the powder circulation housing 11.

In some embodiments, as shown in fig. 11, the gas flow channels are designated as second gas flow channels 121,131, which are provided only in the powder spreading portions 12, 13.

In some embodiments, as shown in fig. 1-2, the gas flow channels are formed by a first gas flow channel 112 and a second gas flow channel 121, 131; wherein the first gas flow passage 112 is provided in the shell layer 111 of the powder circulation housing 11; the second gas flow channels 121,131 are provided in the powder spreading parts 12, 13.

In one embodiment, the gas delivery section 10 is provided as a gas tank as shown in fig. 1,2, capable of controlling the delivery on and off of the gas based on the opening and closing of the valve, and restricting the amount of gas delivery based on the opening of the valve; the valve may be controlled by a computer control system of the 3D printing apparatus. In another embodiment, the gas delivery part 10 may also be provided with a device capable of preparing an inert gas to generate the inert gas to be used in real time as needed. In a specific spatial arrangement, the gas delivery section 10 may be located remotely from the 3D printing apparatus, for example in a designated area with safety precautions to effect a remote delivery of inert gas into the first gas flow channel 112. In other embodiments, the gas delivery unit 10 has a gas delivery pipe 101, and one end of the gas delivery pipe 101 is connected to the gas delivery unit 10, and the other end is connected to the first gas flow channel 112; the gas delivery section 10 delivers the prepared and/or stored inert gas into the first gas flow passage 112 through the gas line 101.

In some preferred embodiments, the inert gas is provided as argon (Ar). It is understood that in practice the present utility model encompasses more inert gas forms other than argon, such as helium (He), neon (Ne), krypton (Kr), and the like, and are within the scope of the present utility model.

The powder circulation shell 11 is a hollow shell with an opening at the bottom surface, and the specific form of the shell is not limited by the utility model, but is preferably a square shell; the powder circulation housing 11 is disposed at a position corresponding to at least the powder overflow area 211; the powder overflow area 211 is formed at the powder outlet of a powder bin 21, and a part of powder overflows from the powder outlet of the powder bin 21 by the ascending and driving of the powder supplying lifting device 26 to form the powder overflow area 211, wherein the powder in the powder overflow area 211 is the powder for being paved on the forming platform 23. More broadly, the powder circulation housing 11 is arranged in a position corresponding to the powder bin 21, the correspondence referred to herein being understood as covering, i.e. at least the powder overflow area 211 is covered within the powder circulation housing 11. In this way, when the inert gas is conveyed into the wrapping space of the powder circulation shell 11 through the first gas flow channel 112, the powder at the powder overflow area 211 corresponding to the powder circulation shell 11 can be disturbed, so that the powder can circularly move in the wrapping space of the powder circulation shell 11 under the disturbance of the inert gas, and further the powder is scattered, i.e. the cluster phenomenon is changed, and becomes looser, thereby being beneficial to better realizing uniform powder spreading on the forming platform 23.

The number of the powder spreading parts 12 and 13 is preferably two, but may be one or more than two in practical application. The specific form of the powder spreading parts 12,13 may be one of a powder spreading brush, a powder spreading roller and a doctor blade, and the doctor blade is preferable in the present utility model. The powder spreading parts 12,13 are provided between the powder circulation housing 11 and the powder overflow area 211, and are configured to spread the powder in a stationary state after the circulation movement, i.e., after the dispersion, to uniformly spread the powder on the forming stage 23. The cyclic motion described herein is a cyclic motion of the powder at the powder overflow area 211 along with the flow of the inert gas in the wrapping space of the powder circulation housing 11. The end of the circulation movement means that the gas delivery portion 10 stops delivering the inert gas into the first gas flow passage 112, and the inert gas in the wrapping space of the powder circulation housing 11 is caused to stop flowing, and the powder in the wrapping space of the powder circulation housing 11 stops the circulation movement. And the powder in the wrapping space of the powder circulation housing 11 falls to be turned into a stationary state after the circulation movement is completed. The powder spreading sections 12,13 spread the powder in a stationary state to uniformly spread it on the forming table 23. The powder is disturbed by the inert gas before being paved and moves circularly in the wrapping space of the powder circulation shell 11 along with the inert flow under the disturbance, so that the powder is loosened; on this basis, the powder after being disturbed by the inert gas is laid on the forming platform 23 (i.e., the uppermost layer of the powder bed 29) by the powder laying sections 12,13, so that a better powder laying effect and more uniform powder laying can be achieved.

In some embodiments, the powder circulation powder spreading device of the present utility model further has a gas spraying portion 14-a,14-b provided at a side of the powder circulation housing 11 and/or the powder spreading portions 12,13 near the powder discharge area 211 for spraying the inert gas in the first gas flow passage 112 into the wrapping space of the powder circulation housing 11. The specific number of the gas spraying parts 14-a,14-b can be adaptively set according to actual use requirements. In a specific spatial arrangement, the gas injection portions 14-a,14-b are provided on the powder circulation housing 11 and/or on the side of the powder spreading portions 12,13 near the powder discharge region 211, and it is also understood that the gas injection portions 14-a are provided on both side inner walls of the powder circulation housing 11 (both side inner walls of the powder circulation housing 11 are on the side near the powder discharge region 211) and/or the gas injection portions 14-b are provided on the side of the powder spreading portions 12 and 13 near the powder discharge region 211. In one embodiment, the gas injection portions 14-a,14-b are provided as nozzles with adjustable injection directions, i.e. the injection angle of the nozzles can be adjusted to change the injection direction of the inert gas.

In one embodiment, as shown in fig. 1 and 2, the first gas flow channel 112 is the inside of the shell layer 111, i.e. the inside of the shell layer 111 of the powder circulation shell 11 is configured to be hollow, so as to form the first gas flow channel 112. It should be understood that the gas pipe 101 communicates with the inside of the shell layer 111 of the powder circulation housing 11, and that the gas delivery portion 10 delivers the inert gas into the shell layer 111 of the powder circulation housing 11 as indicated when the inert gas is delivered into the first gas flow passage 112 through the gas pipe 101. The inert gas is delivered into the shell layer 111 of the powder circulation housing 11, that is, the first gas flow passage 112 via the gas delivery pipe 101, and then the inert gas in the first gas flow passage 112 is injected into the wrapping space of the powder circulation housing 11 by the gas injection parts 14-a, 14-b.

In another embodiment, as shown in fig. 5, the first gas flow passage 112 is provided as a pipe capable of flowing gas to be disposed in the shell layer 111 of the powder circulation housing 11, i.e., the first gas flow passage 112 is provided in the shell layer 111 of the powder circulation housing 11 in an internally hollow state as only a part of the structure provided in the shell layer 111. In this set state, the gas pipe 101 is not in communication with the inside of the shell layer 111 of the powder circulation housing 11, but is in communication with the first gas flow passage 112 provided inside the shell layer 111 of the powder circulation housing 11.

In the above two arrangements of the first gas flow channels 112, the first gas flow channels 112 are disposed in the shell layer 111 of the powder circulation housing 11, and in this arrangement, the inert gas can flow along the longitudinal direction of the powder circulation housing 11, and the length of the inert gas flowing in the longitudinal direction of the powder circulation housing 11 can be distributed over the height of the powder circulation housing 11, so that the inert gas in the first gas flow channels 112 can be conveniently sprayed to the respective heights in the wrapping space of the powder circulation housing 11 through the gas spraying portions 14-a,14-b disposed on the sides of the powder circulation housing 11 and/or the powder spreading portions 12,13 near the powder overflow area 211, thereby achieving more sufficient scattering of the powder.

The connection position of the gas pipe 101 and the first gas flow channel 112, that is, the setting position of the outlet of the gas pipe 101 relative to the powder circulation casing 11 may be set according to actual needs, for example, it may be set above the powder circulation casing 11 as shown in fig. 1 and 2; it may also be provided sideways of the powder circulation casing 11 as shown in fig. 3. In the arrangement form of fig. 3, there are two gas pipelines 101, wherein the outlet of one gas pipeline 101 is arranged on the left side of the powder circulation housing 11, the outlet of the other gas pipeline 101 is arranged on the right side of the powder circulation housing 11, and the two gas pipelines 101 may share one gas delivery part 10, that is, the gas delivery part 10 delivers inert gas to the two gas pipelines 101, respectively; two gas delivery sections 10 may be provided, one of which 10 communicates with one of the gas delivery pipes 101 to deliver the inert gas thereto, and the other 10 communicates with the other gas delivery pipe 101 to deliver the inert gas thereto.

In some embodiments, a one-way valve 15 is provided in the flow path of the inert gas to prevent backflow of the inert gas; wherein the number of the one-way valves can be set according to actual needs.

In some embodiments, the powder circulation housing 11 remains stationary at all times, i.e. at all times in a position corresponding to at least the powder overflow area 211, and may be considered to be above the powder bin 21/the powder overflow area 211 at all times. In this arrangement, the powder spreading parts 12,13 are in a moving state in the powder spreading direction, i.e. they are movably arranged on a plane formed by the powder bin 21/powder overflow area 211 and the powder bed 29 and between the plane and the powder circulation housing 11. Referring to fig. 6, the initial positions of the powder spreading parts 12,13 are below both ends of the powder circulation housing 11, and when the powder in the powder overflow area 211 is in a stationary state after finishing the circulation movement in the wrapping space of the powder circulation housing 11, the powder spreading parts 12,13 start to spread the powder, and the moving stroke of the powder spreading parts 12,13 is controlled by a separate driving mechanism. I.e. the powder spreading parts 12,13 leave the initial position and move in the powder spreading direction to spread the powder in the wrapping space of the powder circulation housing 11 on the forming table 23, i.e. on the uppermost layer of the powder bed 29.

In this arrangement, that is, in a state in which the powder circulation housing 11 is always kept stationary and the powder spreading portions 12,13 are in a moving state in the powder spreading direction, only the gas injection portion 14-a is provided on the side of the powder circulation housing 11 near the powder discharge region 211, and the gas injection portion 14-b provided on the side of the powder spreading portions 12,13 near the powder discharge region 211 is eliminated. And it is preferable that the injection angle of the gas injection part 14-a located at the lowest side of the powder circulation housing 11 near the powder discharge area 211 is set to 45 deg. obliquely downward so as to better blow up the powder of the powder discharge area 211.

In addition, since the powder spreading parts 12,13 are provided separately from the powder circulation housing 11, it is necessary to fix the powder circulation housing 11 at the position thereof by other fixing structures in a specific spatial arrangement.

In some embodiments, the powder circulation housing 11 is movably disposed above the powder discharge region 211 and the forming table 23 to reciprocate above the powder discharge region 211 and the forming table 23. In one embodiment, the initial position of the powder circulation shell 11 is located at a position at least corresponding to the powder overflow area 211, when the powder in the powder overflow area 211 is in circulation motion in the powder circulation shell 11, the powder circulation shell 11 can start to move along the powder spreading direction, so that the powder in the powder circulation shell 11 in circulation motion state in the wrapping space is driven to synchronously move along the powder spreading direction, when the powder circulation shell 11 moves from the position corresponding to the powder overflow area 211 (i.e. the initial position) to the position corresponding to the forming platform 23, the gas conveying part 10 stops conveying inert gas into the first gas flow channel 112, the inert gas stops flowing in the powder circulation shell 11, and the powder in the powder circulation shell 11 is converted from the circulation motion state to the static state on the forming platform 23/the powder bed 29.

Referring to fig. 8, when the powder circulation housing 11 is in a moving state of movement in the powder laying direction, the powder laying portions 12,13 are synchronized with the moving state of the powder circulation housing 11. Specifically, the powder spreading parts 12,13 are fixedly arranged at one end of the powder circulation shell 11 facing the powder overflow area 211 and/or the forming platform 23 so as to synchronously move under the driving of the powder circulation shell 11. That is, the powder spreading parts 12,13 are connected with the powder circulation housing 11, and the concrete connection mode can be integrated molding or be designed as detachable connection. In this arrangement, the powder spreading portions 12,13 are always fixed below both ends of the powder circulation casing 11. When the powder circulation shell 11 moves to a position corresponding to the forming platform 23 and the powder in the wrapping space of the powder circulation shell 11 is changed from a circulation motion state to a static state on the forming platform 23/the powder bed 29, the powder circulation shell 11 is driven to move along the powder spreading direction by a separately arranged driving mechanism, so that the powder spreading parts 12 and 13 are driven to spread the powder, namely the powder spreading parts 12 and 13 are driven to move along the powder spreading direction to spread the powder in the wrapping space of the powder circulation shell 11 on the forming platform 23, namely the powder falling on the forming platform 23 is further spread. Wherein when the powder circulation housing 11 is moved in the powder laying direction to one end of the forming table 23, it is also moved in a direction opposite to the powder laying direction to drive the powder laying sections 12,13 to further lay the powder.

In some embodiments, the gas delivery part 10 stops delivering the inert gas into the first gas flow channel 112 only when the powder circulation housing 11 is moved from the position corresponding to the powder overflow area 211 (i.e., the initial position) to the position corresponding to the forming stage 23, and the position corresponding to the forming stage 23 described herein refers to the position corresponding to the forming workpiece 28 on the forming stage 23, that is, when the powder circulation housing 11 is not moved to the position corresponding to the forming workpiece 28 on the forming stage 23, the gas delivery part 10 still delivers the inert gas into the first gas flow channel 112. As shown in fig. 8, the powder circulation casing 11 does not stop feeding the inert gas when it is within the a section in the powder laying direction, and stops feeding the inert gas only when the powder circulation casing 11 moves to the B section (target position). This can disturb the powder residue remaining at one end (the area between the initial position and the target position) of the forming stage 23 during the movement of the powder circulation housing 11.

In this arrangement, that is, in a state in which the powder circulation housing 11 is in a moving state in the powder laying direction, the powder laying sections 12,13 are synchronized with the moving state of the powder circulation housing 11, the gas ejection section 14-a is provided on the side of the powder circulation housing 11 near the powder discharge region 211, and at the same time, the gas ejection section 14-b is provided on the side of the powder laying sections 12,13 near the powder discharge region 211. And it is preferable that the injection angle of the gas injection part 14-b located at the lowest side of the powder spreading parts 12,13 near the powder discharge area 211 is set to 45 deg. obliquely downward so as to better blow up the powder of the powder discharge area 211.

In some embodiments, as shown in fig. 11, since the second gas flow passages 121,131 are integrated only inside the powder spreading parts 12,13, this arrangement can further reduce the complicated structure of the powder circulation housing 11, simplifying the apparatus. For example, in the present embodiment, the powder spreading portions 12,13 may be doctor blades that uniformly spread the powder from the powder hopper 21 onto the forming table 23. Further, a second gas flow passage 121,131 is arranged in the scraper, the second gas flow passage 121,131 is communicated with the gas pipeline 101, meanwhile, the input inert gas can be sprayed out through the scraper along a gas spraying part 14-b arranged on one side of the scraper close to the powder overflow area 211, and the sprayed gas can disturb powder, so that superfine powder can be subjected to dispersion treatment, and the influence of powder agglomeration on powder paving is prevented. As a simple implementation, a nozzle round hole may be provided on the doctor blade near the powder overflow area 211, which is provided on the doctor blade wall and communicates with the second gas flow channels 121,131 inside the powder spreading parts 12, 13. In some embodiments, as shown in fig. 1-2, a second gas flow channel 121 is provided within the powder spreading portion 12 and a second gas flow channel 131 is provided within the powder spreading portion 13. The second gas flow channels 121,131 are communicated with the first gas flow channel 112, and inert gas is conveyed into the second gas flow channels 121,131 through the first gas flow channel 112 and then is sprayed into the wrapping space of the powder circulation shell 11 through the gas spraying part 14-b arranged on one side of the powder spreading parts 12,13 close to the powder overflow area 211. It should be understood that the second gas flow paths 121,131 are also provided in at least two ways, one of which is to provide the second gas flow paths 121,131 with a space existing inside the powder spreading portion 12,13, that is, to provide at least a part of the inside of the powder spreading portion 12,13 with a hollow shape, so as to form the second gas flow paths 121,131. The other is to provide the second gas flow passages 121,131 as pipes capable of flowing gas to be arranged in the powder paving portions 12,13, i.e., the second gas flow passages 121,131 are only as a part of structures provided in the powder paving portions 12, 13.

Referring to fig. 9, in some embodiments, the powder overflow area is two, and is respectively disposed at two sides of the forming platform, namely, the powder overflow areas 211,221; wherein the powder circulation housing 11 can reciprocate at the positions corresponding to the powder overflow areas 211,221 and the forming table 23 for bi-directional powder laying. It has been described that the powder overflow area 211 is formed at the powder outlet of the powder bin 21, and the powder overflow area 221 is formed at the powder outlet of the powder bin 22, i.e. the double powder bin structure described above. Specifically, after the foregoing powder spreading for the forming stage 23 is completed, the powder circulation housing 11 may continue to move from the position corresponding to the forming stage 23 to the position corresponding to the powder overflow area 221 to disturb the powder formed at the powder overflow area 221 and return to the forming stage 23 for powder spreading, and finally return to the initial position, i.e. the position corresponding to the powder overflow area 211, and repeatedly perform a cycle.

In some embodiments, referring to fig. 1-2,4-5, the powder circulation powder spreading device of the present utility model further has a heating device 16 disposed in the wrapping space of the powder circulation housing 11, and the heating device 16 is configured to preheat the powder in the wrapping space of the powder circulation housing 11. The arrangement of the heating device 16 shown in fig. 1-2,4-5 is only one exemplary arrangement, and in practice the heating device 16 may be arranged at other locations within the enclosure of the powder circulation housing 11 to achieve optimal preheating conditions.

In some embodiments, referring to fig. 4, the powder circulation powder spreading device of the present utility model further has a plasma generating part 17 disposed between the gas transporting part 10 and the first gas flow passage 112 for emitting plasma into the flow path of the inert gas to make the inert gas have charged particles.

The plasma generating section 17 is also controllable by a computer control system of the 3D printing apparatus. Specifically, the plasma generating part 17 may be provided as a plasma generator disposed along the circumference of the plasma channel 171. The plasma generator is capable of generating plasma and releasing the generated plasma into the plasma channel 171; the plasma entering the plasma channel 171 is mixed with the inert gas entering the plasma channel 171 to have charged particles. Wherein, both ends of the plasma channel 171 are respectively communicated with the first gas flow channel 112. When the inert gas having charged particles disturbs the powder in the wrapping space of the powder circulation housing 11, the powder can be made to become more loose, and the powder can be circulated in the wrapping space of the powder circulation housing 11 along with the flow of the inert gas having charged particles, thereby eliminating static electricity of the powder itself.

In one aspect, the utility model further provides a 3D printing device, which has the structure of the powder circulation powder spreading device described above, so as to be mounted on the 3D printing device. In addition to this, a part of the own structure of the 3D printing apparatus has been described in the foregoing and shown in fig. 8, 9.

After the powder spreading process of the utility model is completed, the next stage of work is performed, for example, a light path unit of the 3D printing equipment is started to act on the powder on the forming platform so as to perform forming and manufacturing of the workpiece.

In the description of the present specification, a description referring to terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present utility model. In this specification, schematic representations of the above terms are not necessarily directed to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, the different embodiments or examples described in this specification and the features of the different embodiments or examples may be combined and combined by those skilled in the art without contradiction.

In the present utility model, unless expressly stated or limited otherwise, a first feature "up" or "down" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature being "above," "over" and "on" a second feature may be a first feature being directly above or obliquely above the second feature, or simply indicating that the first feature is level higher than the second feature. The first feature being "under", "below" and "beneath" the second feature may be the first feature being directly under or obliquely below the second feature, or simply indicating that the first feature is less level than the second feature.

While embodiments of the present utility model have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the utility model, and that variations, modifications, alternatives and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the utility model.

Reference numerals illustrate:

gas delivery section 10

Gas pipeline 101

Powder circulation casing 11

Shell layer 111

First gas flow passage 112

Powder spreading parts 12,13

Second gas flow channels 121,131

Gas injection portions 14-a,14-b

Check valve 15

Heating device 16

Plasma generating portion 17

Plasma channel 171

Powder bins 21,22

Powder overflow areas 211,221

Forming table 23

Shaping magazine 24

Shaping lifting device 25

Powder supply lifting devices 26, 27

Forming work piece 28

Powder bed 29

Claims (11)

1. A powder circulation shop's powder device for 3D printing apparatus, characterized in that includes:

a gas delivery section for delivering the prepared and/or stored inert gas into at least one gas flow passage;

the powder circulation shell is arranged at a position which can at least correspond to a powder overflow area, wherein the inert gas is conveyed into a wrapping space of the powder circulation shell through the gas flow channel so as to disturb powder at the powder overflow area corresponding to the powder circulation shell, and the powder is circulated in the wrapping space of the powder circulation shell under the disturbance of the inert gas so as to be dispersed;

the powder spreading part is arranged between the powder circulation shell and the powder overflowing area and is used for spreading the scattered powder so as to uniformly spread the powder on a forming platform; and

the gas spraying part is arranged at one side of the powder circulating shell and/or the powder spreading part, which is close to the powder overflowing area, and is used for spraying inert gas in the gas flow channel into the wrapping space of the powder circulating shell;

wherein the gas flow passage is arranged in the shell layer of the powder circulation shell and/or the powder paving part.

2. A powder circulation spreading device according to claim 1, wherein the powder overflow area is formed at a powder outlet of at least one powder bin.

3. The powder circulation powder spreading device according to claim 1, wherein the gas delivery section comprises a gas delivery pipe, wherein the gas delivery pipe is in communication with the gas flow passage, and wherein the gas delivery section is configured to deliver the prepared and/or stored inert gas into the gas flow passage through the gas delivery pipe.

4. The powder circulation spreading device according to claim 1, wherein the gas spraying portion is a nozzle with an adjustable spraying direction.

5. A powder circulation spreading device according to claim 1, wherein the powder circulation housing is movably arranged above the powder overflow area and the forming table to reciprocate above the powder overflow area and the forming table.

6. A powder circulation powder spreading device according to claim 5, wherein the powder spreading portion is fixedly arranged at one end of the powder circulation housing facing the powder overflow area and/or the forming platform so as to be synchronously moved under the drive of the powder circulation housing.

7. The powder circulation powder spreading device according to claim 6, wherein the gas flow passage is constituted by a first gas flow passage and a second gas flow passage; wherein the first gas flow passage is arranged in a shell layer of the powder circulation shell; the second gas flow passage is arranged in the powder spreading part, wherein the second gas flow passage is communicated with the first gas flow passage, the inert gas is conveyed into the second gas flow passage through the first gas flow passage, and then is sprayed into the wrapping space of the powder circulation shell through the gas spraying part arranged on one side of the powder spreading part, which is close to the powder overflow area.

8. The powder circulating powder spreading device according to claim 5, wherein the powder overflow areas are arranged at two positions and are respectively arranged at two sides of the forming platform; wherein the powder circulation shell can reciprocate on two powder overflow areas and corresponding positions of the forming platform to perform bidirectional powder paving.

9. The powder circulation spreading device according to claim 1, further comprising:

and the heating device is arranged in the wrapping space of the powder circulation shell and is used for preheating the powder in the wrapping space of the powder circulation shell.

10. The powder circulation spreading device according to claim 1, further comprising:

and a plasma generating part arranged between the gas conveying part and the gas flow channel and used for emitting plasma into the flow path of the inert gas so as to enable the inert gas to have charged particles.

11. A 3D printing apparatus, characterized in that the 3D printing apparatus comprises a structure in which the powder circulation powder spreading device according to any one of claims 1 to 10 is mounted to the 3D printing apparatus.

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