CN112060588A

CN112060588A - Forming bin smoke exhaust system and powder bed 3D printing equipment

Info

Publication number: CN112060588A
Application number: CN202010902290.4A
Authority: CN
Inventors: 俞红祥; 庞伟; 刘浪
Original assignee: Hangzhou Dedi Intelligent Technology Co ltd
Current assignee: Hangzhou Dedi Intelligent Technology Co ltd
Priority date: 2020-09-01
Filing date: 2020-09-01
Publication date: 2020-12-11

Abstract

The invention relates to powder bed 3D printing equipment and a forming bin smoke exhaust system. The exhaust airflow includes a main airflow flowing in a first direction and an auxiliary airflow flowing obliquely with respect to the first direction. That is, the main air flow can be blown toward the exhaust assembly in the horizontal direction, and the auxiliary air flows on both sides can be blown toward the exhaust assembly from obliquely below and obliquely above, respectively. Therefore, the auxiliary airflow enables the smoke exhaust airflow to quickly capture smoke and play a good constraint role on the smoke, so that efficient smoke exhaust is realized. Moreover, the auxiliary air flow can respectively restrain the main air flow from below and above, so that the smoke exhaust air flow is prevented from disturbing the powder layer downwards and diffusing upwards to disturb the laser beam. Therefore, the disturbance to the powder layer and the laser beam in the smoke exhaust process of the smoke exhaust system of the molding bin is obviously reduced, so that the consistency of the process is improved.

Description

Forming bin smoke exhaust system and powder bed 3D printing equipment

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to a forming bin smoke exhaust system and powder bed 3D printing equipment.

Background

Powder bed 3D prints because of its advantages such as high accuracy, surface quality are good, is widely used in the forming process of metal, macromolecular material even ceramic part. Moreover, since the laser spot and the powder particles can be as small as tens of microns, SLM (selective laser melting) and SLS (selective laser sintering) have higher precision compared to other processes, and become two most common powder bed 3D printing and forming methods.

Powder bed 3D printing equipment for SLM (selective laser melting) process or SLS (selective laser sintering) process generally comprises a powder supply and powder spreading device, a laser head, a forming bin and a forming cylinder, wherein a powder layer with uniform thickness is laid in an opening area of the forming cylinder, and then a selected area of the powder layer is irradiated by laser scanning to be heated and combined into a sheet. Repeating the above process for multiple times, and vertically accumulating the sheet-shaped object generated by combining each layer of powder and the sheet-shaped object of the previous layer to gradually form a complete three-dimensional formed body.

The powder can produce the flue gas when being heated by laser, and the flue gas that produces needs in time to be discharged. However, the high-speed airflow during the fume extraction may cause disturbance of the powder layer. Further, the energy of the laser beam for irradiating the powder layer is also disturbed by the influence of the smoke. This results in poor consistency of the powder bed 3D printing apparatus.

Disclosure of Invention

In view of the above, it is necessary to provide a forming bin smoke evacuation system and a powder bed 3D printing apparatus capable of improving process consistency.

The utility model provides a shaping storehouse system of discharging fume, is including locating the exhaust subassembly and the subassembly that admits air of the regional relative both sides of shop's powder in the shaping storehouse, admit air the subassembly be used for to exhaust subassembly blows the air current of discharging fume, exhaust subassembly is used for the suction the air current of discharging fume, the air current of discharging fume includes along the main air current that first direction flows and is located the auxiliary air current of main air current second direction upper and lower both sides, the second direction with first direction is perpendicular, both sides the auxiliary air current along for the direction flow direction of first direction slope is to exhaust subassembly, and by admit air the subassembly arrives gradually to in the direction of exhaust subassembly the main air current draws close.

In one embodiment, the exhaust assembly has an exhaust port, the intake assembly has first auxiliary intake ports, second auxiliary intake ports and a main intake port located between the first auxiliary intake ports and the second auxiliary intake ports, the main intake port and the exhaust port are aligned in the first direction and are configured to blow the main airflow, and the first auxiliary intake ports and the second auxiliary intake ports are directed obliquely to the exhaust port with respect to the first direction and are configured to blow the auxiliary airflow.

In one embodiment, the first auxiliary air inlet and the second auxiliary air inlet are strip-shaped, and both the first auxiliary air inlet and the second auxiliary air inlet extend along a third direction perpendicular to the first direction and the second direction.

In one embodiment, the circulation assembly comprises a filter, a main circulation pump and an auxiliary circulation pump, wherein the air inlet end of the main circulation pump is communicated with the air outlet through the filter, the air outlet end of the main circulation pump is communicated with the air inlet end of the auxiliary circulation pump and the main air inlet, and the air outlet end of the auxiliary circulation pump is communicated with the first auxiliary air inlet and the second auxiliary air inlet.

In one embodiment, the circulation assembly further includes a main wind speed sensor disposed at an outlet end of the main circulation pump for acquiring a wind speed at the outlet end of the main circulation pump, and an auxiliary wind speed sensor disposed at an outlet end of the auxiliary circulation pump for acquiring a wind speed at the outlet end of the auxiliary circulation pump.

In one embodiment, the exhaust assembly and the intake assembly are driven by the displacement assembly to move along a direction perpendicular to the first direction and the second direction.

In one embodiment, the exhaust component and the intake component move synchronously under the driving of the displacement component.

In one embodiment, the displacement assembly comprises a driving member and linear slide rails which are respectively arranged on two opposite sides of the powder spreading area and are parallel to each other, and the exhaust assembly and the air intake assembly are respectively slidably arranged on the two linear slide rails and are in transmission connection with the driving member.

A powder bed 3D printing apparatus comprising:

the powder spreading device comprises a frame, a forming bin and a forming cylinder, wherein the forming bin and the forming cylinder are arranged on the frame, a powder spreading area is formed at the bottom of the forming bin, the forming cylinder is in butt joint with the bottom of the forming bin, and an opening area of the forming cylinder is arranged corresponding to the powder spreading area; and

the laser is arranged at the top of the molding bin and is used for irradiating the opening region;

a molding silo fume extraction system as described in any of the above preferred embodiments;

wherein the first direction is parallel to the surface of the powder spreading area, the second direction is perpendicular to the surface of the powder spreading area, and the smoke exhaust airflow can flow between the powder spreading area and the laser.

In one embodiment, the molding machine further comprises a controller in communication with the molding bin smoke evacuation system, wherein the controller can adjust the flow rates of the primary air flow and the secondary air flow such that the flow rate of the secondary air flow is greater than the flow rate of the primary air flow.

Above-mentioned powder bed 3D printing apparatus and shaping storehouse system of discharging fume, when the exhaust stream flows through the shop powder region, can blow the produced flue gas of laser irradiation powder to exhaust subassembly. The exhaust airflow includes a main airflow flowing in a first direction and an auxiliary airflow flowing obliquely with respect to the first direction. That is, the main air flow can be blown toward the exhaust assembly in the horizontal direction, and the auxiliary air flows on both sides can be blown toward the exhaust assembly from obliquely below and obliquely above, respectively. Therefore, the auxiliary airflow enables the smoke exhaust airflow to quickly capture smoke and play a good constraint role on the smoke, so that efficient smoke exhaust is realized. Moreover, the auxiliary air flow can respectively restrain the main air flow from below and above, so that the smoke exhaust air flow is prevented from disturbing the powder layer downwards and diffusing upwards to disturb the laser beam. Therefore, the disturbance to the powder layer and the laser beam in the smoke exhaust process of the smoke exhaust system of the molding bin is obviously reduced, so that the consistency of the process is improved.

Drawings

In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

FIG. 1 is a schematic diagram of a 3D printing apparatus for powder bed according to a preferred embodiment of the present invention;

FIG. 2 is a front view of the powder bed 3D printing apparatus shown in FIG. 1;

FIG. 3 is a schematic view of the smoke evacuation system of the molding bin in accordance with the preferred embodiment of the present invention;

FIG. 4 is a schematic view of an air intake assembly of the molding bin smoke evacuation system of FIG. 3;

fig. 5 is a schematic view of a powder plane.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

In the description of the present invention, it is to be understood that the terms "central," "longitudinal," "lateral," "length," "width," "thickness," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," "outer," "clockwise," "counterclockwise," "axial," "radial," "circumferential," and the like are used in the orientations and positional relationships indicated in the drawings for convenience in describing the invention and to simplify the description, and are not intended to indicate or imply that the referenced device or element must have a particular orientation, be constructed and operated in a particular orientation, and are not to be considered limiting of the invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one such feature. In the description of the present invention, "a plurality" means at least two, e.g., two, three, etc., unless specifically limited otherwise.

In the present invention, unless otherwise expressly stated or limited, the terms "mounted," "connected," "secured," and the like are to be construed broadly and can, for example, be fixedly connected, detachably connected, or integrally formed; can be mechanically or electrically connected; they may be directly connected or indirectly connected through intervening media, or they may be connected internally or in any other suitable relationship, unless expressly stated otherwise. The specific meanings of the above terms in the present invention can be understood by those skilled in the art according to specific situations.

In the present invention, unless otherwise expressly stated or limited, the first feature "on" or "under" the second feature may be directly contacting the first and second features or indirectly contacting the first and second features through an intermediate. Also, a first feature "on," "over," and "above" a second feature may be directly or diagonally above the second feature, or may simply indicate that the first feature is at a higher level than the second feature. A first feature being "under," "below," and "beneath" a second feature may be directly under or obliquely under the first feature, or may simply mean that the first feature is at a lesser elevation than the second feature.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "upper," "lower," "left," "right," and the like as used herein are for illustrative purposes only and do not denote a unique embodiment.

Referring to fig. 1 and 2, the present invention provides a powder bed 3D printing apparatus 10 and a molding bin smoke evacuation system 500. The powder bed 3D printing apparatus 10 includes a frame 100, a forming chamber 200, a forming cylinder 300, a laser head 400, a forming chamber smoke evacuation system 500, and a controller (not shown).

The frame 110 mainly plays a supporting role, is generally formed by assembling and welding metal rods and plates, and has good rigidity. The molding hopper 200 and the molding cylinder 300 are provided on the frame 110. The molding bin 200 may be a cavity structure formed by splicing a plurality of plates, and is in a closed state during printing. A powder spreading area (not shown) is formed at the bottom of the molding bin 200, and when printing is performed, raw material powder is spread in the powder spreading area to form a powder plane. The forming cylinder 300 is generally a cylindrical structure having an opening. Furthermore, the molding cylinder 300 is abutted with the bottom of the molding bin 200, and the opening area of the molding cylinder 300 is arranged corresponding to the powder spreading area. That is, the open area overlaps the powder spreading area, and the powder plane is located within the open area.

The forming cylinder 300 is provided with a forming platform 310, and the forming platform 310 can move up and down and be positioned in the forming cylinder 300, so that the height of the powder plane can be kept consistent after each powder laying. Wherein the forming platform 310 moves to the top dead center (highest point) and is flush with the bottom surface of the forming chamber 200. The timing of the movement of the forming platform 310 and the step length of each movement can be controlled by the controller.

A laser 400 is provided at the top of the molding cartridge 200 and is used to irradiate the open area. The laser beam from the laser 400 heats the powder plane in the open area until the powder melts or sinters to obtain a sheet. As shown in fig. 5, the powder plane 30 has a plurality of specific regions (e.g., a first specific region 301 and a second specific region 302) according to the shape of the object to be printed. The laser 400 can select a specific area at a time to perform laser scanning under the control of the controller, so as to obtain the required shape of each layer of the sheet-like object.

The structure and function of the frame 100, the forming chamber 200, the forming cylinder 300, the laser head 400 and the controller in the powder bed 3D printing apparatus 10 are similar to those in the conventional powder bed 3D printing apparatus, and therefore, the description thereof is omitted.

Referring also to FIG. 3, the system 500 for exhausting flue gases from a molding bin of the preferred embodiment of the present invention includes an exhaust assembly 510 and an intake assembly 520. Wherein, the exhaust component 510 and the air intake component 520 are respectively disposed at two opposite sides of the powder spreading region in the molding bin 200.

The air intake assembly 520 is used to blow the flue gas stream 20 toward the exhaust assembly 510, and the exhaust assembly 510 is used to draw the flue gas stream 20. Further, the smoke exhaust flow 20 includes a main flow 201 and an auxiliary flow 202 located in the main flow 201. The main airflow 201 flows in a first direction, and the auxiliary airflow 202 is located on both sides of the main airflow 201 in a second direction perpendicular to the first direction. Wherein the first direction is parallel to the surface of the powder coated area (i.e., parallel to the powder plane 30) and the second direction is perpendicular to the surface of the powder coated area (i.e., perpendicular to the powder plane 30), the smoke exhaust stream 20 can flow between the powder coated area and the laser 400.

Moreover, the auxiliary airflow 202 on both sides flows toward the exhaust assembly 510 in a direction inclined with respect to the first direction, and gradually converges toward the main airflow 201 in a direction from the intake assembly 520 to the exhaust assembly 510.

As shown in fig. 1 and 2, when the powder bed 3D printing apparatus 10 is operated, the first direction is a horizontal direction, and the second direction is a vertical direction. The smoke exhaust 20 blows from right to left to the exhaust assembly 510, the main airflow 201 blows towards the exhaust assembly 510 along the horizontal direction, the auxiliary airflow 202 is located at the upper and lower sides of the main airflow 201, and the auxiliary airflow 202 at the two sides respectively blows towards the exhaust assembly 510 along the obliquely upper and obliquely lower directions.

Referring to fig. 4, in the present embodiment, the exhaust assembly 510 has an exhaust port 511, and the intake assembly 520 has a first auxiliary intake port 521, a second auxiliary intake port 522 and a main intake port 523 located between the first auxiliary intake port 521 and the second auxiliary intake port 522, which are spaced apart from each other in the second direction. Wherein the primary air inlet 523 is aligned with the air outlet 511 in the first direction and is used to blow the primary air flow 201. The first auxiliary intake 521 and the second auxiliary intake 522 are directed obliquely to the exhaust 511 with respect to the first direction, and are used to blow the auxiliary airflow 202.

For the sake of convenience, the auxiliary airflow 202 blown out by the first auxiliary air inlet 521 and the second auxiliary air inlet 522 is referred to as a first auxiliary airflow and a second auxiliary airflow, respectively. Since the air inlet 523 is aligned with the air outlet 511 in the first direction, the main air flow 201 blown through the main air inlet 523 will be blown horizontally toward the air outlet 511 in the first direction. As shown in fig. 3 and 4, the first auxiliary air inlet 521 is located below the main air inlet 523, and the second auxiliary air inlet 522 is located above the main air inlet 523, so that the first auxiliary air flow and the second auxiliary air flow are respectively blown toward the air outlet 511 in the obliquely upward and obliquely downward directions.

As the flue gas stream 20 flows through the dusting area, flue gas generated by the laser irradiation of the powder planes 30 may be blown toward the exhaust assembly 510. Moreover, the first auxiliary airflow blowing obliquely upwards can blow the flue gas to the main airflow 201 quickly, so that the flue gas can be captured quickly. The smoke exhaust 20 can be blown towards the exhaust assembly 510 in a horizontal direction, and the auxiliary air flows 202 on both sides can be blown towards the exhaust assembly 510 from an obliquely lower direction and an obliquely upper direction, respectively. Therefore, the smoke exhaust airflow 20 can play a good constraint role on smoke, and efficient smoke exhaust is realized.

Further, the auxiliary airflow 202 on both sides of the main airflow 201 can restrict the main airflow 201 from below and above, respectively. The first auxiliary air flow is blown obliquely upwards, so that the Coanda effect (wall attachment effect) can be inhibited, and the form change and particle attachment of the powder plane 30 caused by the direct interference of the smoke exhaust air flow 20 on the powder plane 30 can be avoided; the first auxiliary airflow is blown obliquely downwards, so that the smoke of the boundary turbulent layer of the main airflow 201 can be suppressed to be diffused upwards freely, the upper space of the forming bin 200 is kept clean, and the smoke is prevented from interfering the laser 400. Therefore, the disturbance to the powder plane 30 and the laser beam in the smoke discharging process is obviously reduced, and the consistency can be improved.

In addition, the first auxiliary airflow can continuously push the smoke obliquely upward, and when the heavier particles in the main airflow 201 are settled, the first auxiliary airflow can apply the obliquely upward pushing force to the smoke again to enable the smoke to ascend again. During the process of the smoke discharging with the smoke exhaust flow 20 towards the exhaust assembly 510, the first auxiliary flow can repeatedly exert an upward thrust on the settling motion of the larger particles, so that the larger particles can move along the wave-shaped path, thereby preventing the larger particles from falling onto the powder plane 30 before entering the exhaust opening 511, and further reducing the disturbance of the powder plane 30.

Referring to fig. 3 again, in the present embodiment, the first auxiliary intake port 521 and the second auxiliary intake port 522 are bar-shaped, and both the first auxiliary intake port 521 and the second auxiliary intake port 522 extend along a third direction perpendicular to the first direction and the second direction.

The third direction is the direction perpendicular to the plane of the drawing sheet as shown in fig. 4. Since the first auxiliary intake port 521 and the second auxiliary intake port 522 have a strip shape, the auxiliary airflow 202 blown out through the first auxiliary intake port 521 and the second auxiliary intake port has a flat shape. On the premise of a certain gas flow, the flow speed of the flat auxiliary gas flow 202 is faster, so that the constraint effect on the flue gas is more obvious. Moreover, the flat auxiliary airflow 202 covers a wider area, and can effectively prevent the side smoke from escaping.

Referring to fig. 1 and fig. 2 again, in the present embodiment, the smoke exhausting system 500 of the forming chamber further includes a circulating component 530. The circulation component 530 includes a filter 531, a main circulation pump 532, and an auxiliary circulation pump 533. The air inlet end of the main circulating pump 532 is communicated with the air outlet 511 through the filter 531, the air outlet end of the main circulating pump 522 is communicated with the air inlet end of the auxiliary circulating pump 533 and the main air inlet 523, and the air outlet end of the auxiliary circulating pump 533 is communicated with the first auxiliary air inlet 521 and the second auxiliary air inlet 522.

The filter 531, the main circulation pump 532, and the auxiliary circulation pump 533 can be connected to the exhaust port 511 and the air inlet port (the first auxiliary air inlet 521, the second auxiliary air inlet 522, and the main air inlet 523, which will be collectively referred to as air inlet ports hereinafter) by hoses. Wherein, the air outlet ends of the main circulating pump 532 and the auxiliary circulating pump 533 are connected with a one-to-two pipe. During 3D printing, the molding chamber 200 needs to be filled with inert gas to prevent the powder material from being oxidized. The circulation assembly 530 may purify the inert gas and recycle the inert gas after circulating between the exhaust assembly 510 and the intake assembly 520, thereby saving costs.

Specifically, the exhaust gas 20 enters the filter 531 through the exhaust port 511, and the exhaust gas and the particulate matters are filtered; next, the main circulation pump 522 blows a part of the purified gas from the main gas inlet 523 to form the main gas flow 201, and the other part of the purified gas is sent to the auxiliary circulation pump 533 and blown by the auxiliary circulation pump 533 through the first auxiliary gas inlet 521 and the second auxiliary gas inlet 522 to form the auxiliary gas flow 202.

The main circulation pump 522 is used for establishing positive pressure between the inlet and the outlet of the filter 531, so as to increase the filtration efficiency and pressurize the filtered clean gas to make the flow velocity reach the wind velocity required by the main air inlet 523; the auxiliary circulating pump 533 is used for secondarily pressurizing the clean gas diverted by the main circulating pump 532, so that the flow velocity of the clean gas reaches the wind velocity required by the first auxiliary air inlet 521 and the second auxiliary air inlet 522. In addition, by providing the main circulation pump 532 and the auxiliary circulation pump 533, the flow rates of the main airflow 201 and the auxiliary airflow 202 can be independently controlled, so as to meet the requirements of different smoke discharge scenes on the flow rate combination of the auxiliary airflow 202 and the main airflow 201.

Further, in this embodiment, the circulation assembly 530 further includes a main wind speed sensor (not shown) disposed at an outlet end of the main circulation pump 532 for acquiring a wind speed at the outlet end of the main circulation pump 532, and an auxiliary wind speed sensor (not shown) disposed at an outlet end of the auxiliary circulation pump 533 for acquiring a wind speed at the outlet end of the auxiliary circulation pump 533.

Through setting up main air velocity transducer and supplementary air velocity transducer, can acquire the velocity of flow of supplementary air current 202 and main air current 201 in real time to be convenient for in time adjust the wind speed of main circulating pump 532 and supplementary circulating pump 533 as required.

Further, a controller is communicatively coupled to the molding bin purge system 500, and the controller can adjust the flow rates of the primary and secondary air flows 201, 202 such that the flow rate of the secondary air flow 202 is greater than the flow rate of the primary air flow 201.

Specifically, the controller is in communication connection with the main circulation pump 532, the auxiliary circulation pump 533, the main wind speed sensor, and the auxiliary wind speed sensor, respectively. The main wind speed sensor and the auxiliary wind speed sensor upload the collected wind speed information to the controller, and the controller can adjust the power of the main circulating pump 532 and the auxiliary circulating pump 533 according to the current wind speed information, so that the flow rates of the auxiliary airflow 202 and the main airflow 201 meet the requirements.

In this embodiment, the molding chamber smoke evacuation system 500 further includes a displacement assembly 540, and the displacement assembly 540 can drive the exhaust assembly 510 and the intake assembly 520 to move along a direction perpendicular to the first direction and the second direction.

Specifically, the laser 400 needs to continuously adjust the scanning area irradiated on the powder plane 30 according to different shape requirements during the process of heating the powder. The direction perpendicular to the first direction and the second direction is the third direction, and the air inlet component 520 can make the smoke discharging airflow 20 cover the whole powder plane in sequence by moving along the third direction. In this way, the exhaust module 510 and the air intake module 520 can move along with the laser irradiation point, so the widths of the exhaust port 511 and the air intake port do not need to exceed the width of the powder plane 30, and only the width of the blown smoke discharging airflow 20 can cover the range of smoke in the moving process of the displacement module 540. Therefore, the width of the air outlet 511 and the air inlet can be reduced significantly, so that the air flow distribution of the air outlet 511 and the air inlet is more uniform and the flow rate is more stable.

As shown in fig. 5, the powder plane 30 has two specific regions, i.e., a first specific region 301 and a second specific region 302, which need to be scanned by the laser. After the first specific area 301 is heated by the laser beam, the laser irradiation point moves downward to the second specific area 302. At this time, the displacement assembly 540 drives the exhaust assembly 510 and the gas inlet assembly 520 to move downward along with the laser irradiation point.

Further, in the present embodiment, the exhaust assembly 510 and the intake assembly 520 are driven by the displacement assembly 450 to move synchronously. Because the two move synchronously, the relative position can be kept unchanged all the time. Therefore, the relative positions of the laser irradiation point and the laser beam are calibrated and debugged only in the initial state, and multiple times of calibration and debugging are not needed in the subsequent process of moving along with the laser irradiation point, so that the efficiency is improved.

Furthermore, in the present embodiment, the displacement assembly 540 includes a driving member (not shown) and linear sliding rails (not shown) respectively disposed on two opposite sides of the powder spreading area and parallel to each other, and the exhaust assembly 510 and the air intake assembly 520 are respectively slidably disposed on the two linear sliding rails and are in transmission connection with the driving member.

Specifically, the exhaust assembly 510 and the intake assembly 520 may be engaged with a linear slide rail through a slider, so that the exhaust assembly 510 and the intake assembly 520 may be kept stable and the relative positions may be kept stable during the movement process.

According to the powder bed 3D printing device 10, when the smoke exhaust airflow 20 flows through the powder spreading area, smoke generated by laser irradiation of powder can be blown to the exhaust assembly 510. Further, the exhaust flow 20 includes a main flow 201 flowing in a first direction and an auxiliary flow 202 flowing obliquely to the first direction on both sides. That is, the main airflow 201 may be blown toward the exhaust assembly 510 in a horizontal direction, and the auxiliary airflows 202 on both sides may be blown toward the exhaust assembly 510 from an obliquely lower direction and an obliquely upper direction, respectively. Therefore, the auxiliary airflow 202 enables the smoke exhaust airflow 20 to capture smoke quickly and play a good constraint role on the smoke, thereby realizing efficient smoke exhaust. Moreover, the secondary air flow 202 is able to constrain the primary air flow 201 from below and above, respectively, so as to avoid the fume exhaust flow 20 from disturbing the powder bed downwards, and from diffusing upwards to disturb the laser beam. Therefore, the disturbance of the powder bed 3D printing device 10 and the forming bin smoke evacuation system 500 to the powder bed and the laser beam during smoke evacuation is significantly reduced, so that the consistency of the process is improved.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. The utility model provides a shaping storehouse system of discharging fume, its characterized in that, is including locating the exhaust subassembly and the subassembly that admits air of the regional relative both sides of shop's powder in the shaping storehouse, the subassembly that admits air is used for to exhaust subassembly blows the air current of discharging fume, the air current of discharging fume is used for the suction the air current of discharging fume, the air current of discharging fume includes along the main air current that first direction flows and is located the auxiliary air current of both sides in the main air current second direction, the second direction with first direction is perpendicular, both sides the auxiliary air current along for the direction flow direction of first direction slope is to exhaust subassembly, and by admit air the subassembly arrive gradually in the direction of exhaust subassembly main air current draws close.

2. The contour bin smoke evacuation system of claim 1, wherein the exhaust assembly has an exhaust outlet, the intake assembly has first and second auxiliary intake ports spaced apart in the second direction and a primary intake port between the first and second auxiliary intake ports, the primary intake port and the exhaust outlet aligned in the first direction and configured to blow the primary airflow, the first and second auxiliary intake ports being obliquely directed toward the exhaust outlet relative to the first direction and configured to blow the secondary airflow.

3. The system of claim 2, wherein the first and second auxiliary air inlets are strip-shaped and extend in a third direction perpendicular to the first and second directions.

4. The smoke exhaust system for a forming bin according to claim 2, further comprising a circulation assembly, wherein the circulation assembly comprises a filter, a main circulation pump and an auxiliary circulation pump, an air inlet end of the main circulation pump is communicated with the exhaust port through the filter, an air outlet end of the main circulation pump is communicated with an air inlet end of the auxiliary circulation pump and the main air inlet, and an air outlet end of the auxiliary circulation pump is communicated with the first auxiliary air inlet and the second auxiliary air inlet.

5. The smoke evacuation system for a molding bin of claim 4, wherein the circulation assembly further comprises a main wind speed sensor disposed at an outlet end of the main circulation pump for acquiring a wind speed at the outlet end of the main circulation pump and an auxiliary wind speed sensor disposed at an outlet end of the auxiliary circulation pump for acquiring a wind speed at the outlet end of the auxiliary circulation pump.

6. The system of claim 1, further comprising a displacement assembly configured to move the exhaust assembly and the intake assembly in a direction perpendicular to the first direction and the second direction.

7. The system of claim 6, wherein the exhaust assembly and the intake assembly move synchronously under the driving of the shift assembly.

8. The smoke evacuation system for a molding bin of claim 6, wherein the displacement assembly comprises a driving member and linear slide rails respectively disposed on two opposite sides of the powder spreading area and parallel to each other, and the exhaust assembly and the air intake assembly are respectively slidably disposed on the two linear slide rails and are in transmission connection with the driving member.

9. A powder bed 3D printing apparatus, comprising:

a moulding chamber smoke evacuation system as claimed in any one of claims 1 to 8;

10. The powder bed 3D printing apparatus of claim 9, further comprising a controller in communication with the form bin fume extraction system, the controller being configured to adjust the flow rates of the primary and secondary air flows such that the flow rate of the secondary air flow is greater than the flow rate of the primary air flow.