Two-way dust scraping and feeding system based on multiple powders

Abstract

This utility model relates to the field of additive manufacturing technology, specifically to a bidirectional powder feeding system based on multiple powders, comprising: a powder spreading bin, the interior of which is configured with a predetermined protective atmosphere to form an environment for laser sintering powder, the bottom of the powder spreading bin having a powder scraping plane; and a scraper component connected to a track on the inner wall of the powder spreading bin. Through real-time linkage between a movable return powder bin and a powder supply bin, the return powder bin can be switched synchronously according to the current powder type. Simultaneously, the scraper component can perform bidirectional powder scraping. When scraping powder bidirectionally, the position of the return powder bin can be dynamically adjusted according to the scraper direction to ensure that the falling powder enters the corresponding return powder bin, with no powder spillage. The powder supply and return efficiency is high, the purity is high, and it can be directly recycled and reused. Furthermore, the scraper component is designed to temporarily store powder, enabling bidirectional powder scraping in a single powder feeding, thus improving processing efficiency.

Description

Technical Field

[0001] This utility model relates to the field of additive manufacturing technology, and more specifically to a bidirectional powder feeding system based on multiple powders. Background Technology

[0002] Selective laser melting (SLM) technology manufactures complex metal parts by layer-by-layer powder deposition and laser melting. However, in various scenarios, such as functional graded materials and composite structure manufacturing, multiple types of powders need to be dynamically switched to achieve additive manufacturing. Therefore, the limitations of single materials are significant, and additive manufacturing technology is developing towards dynamic switching of multiple powders.

[0003] Currently, the processing flow of multi-material SLM typically includes the following steps: Layered design and powder distribution: Based on the 3D model of the part, determine the required powder type for each layer (e.g., layers 1-2 use powder A, layers 2-4 use powder B). Powder supply system switching: Release powder onto the surface of the forming cylinder as needed through multiple powder supply bins (each bin stores one type of powder). Powder spreading and leveling: A scraper evenly spreads the powder, and excess powder is scraped into a recovery bin. Laser melting: A laser selectively melts the powder in the current layer along a preset path to form the cross-section of the part. Powder recovery and recycling: The recovery bin collects excess powder, which is then sieved and reused.

[0004] For example, in the SLM forming equipment with a multi-material powder spreading device proposed in publication number CN116117172A, the powder feeding device is set on one side, the scraper can only scrape powder in one direction, and multiple powders are mixed in the powder recovery bin, which is not conducive to the subsequent powder screening. Therefore, people hope to develop a powder feeding system for multiple powders to improve the processing efficiency of multi-material SLM. Summary of the Invention

[0005] To address the technical problems existing in current laser selective melting equipment, this utility model proposes a bidirectional powder feeding system based on multiple powders, comprising:

[0006] The powder spreading chamber is configured with a predetermined protective atmosphere to create an environment for laser sintering powder, and the bottom of the powder spreading chamber is provided with a powder scraping surface.

[0007] The scraper component is connected to a track on the inner wall of the powder spreading chamber and can be driven to reciprocate along the first direction extending along the track, touching the powder scraping plane.

[0008] A forming cylinder is located below the powder scraping plane of the powder spreading chamber and communicates with the inner cavity of the powder spreading chamber. A forming substrate is provided inside the forming cylinder. The forming substrate is configured to move upward or downward inside the forming cylinder. A first powder return area and a second powder return area are respectively provided on both sides of the forming cylinder. Both the first powder return area and the second powder return area are provided with powder return channels.

[0009] A powder supply component is used to quantitatively supply two or more types of powder to the scraper component, and the powder supply component is located above the first powder return area and / or the second powder return area;

[0010] The powder return component includes two powder return chamber groups, which are located below the first powder return area and the second powder return area, respectively.

[0011] The powder return chamber group includes two or more powder return chambers and a driving component that drives any one of the powder return chambers to the corresponding position of the powder return channel. The driving component is used to drive the powder return chamber to move so that the powder return channel below the starting and ending positions of the scraper component is the powder return chamber corresponding to the current powder type.

[0012] Preferably, the powder supply component includes a powder supply chamber A, a first powder supply shaft disposed below the powder supply chamber A, a powder supply chamber B, and a second powder supply shaft disposed below the powder supply chamber B. The powder supply chamber A is located on the first side of the forming cylinder, and the powder supply chamber B is located on the second side of the forming cylinder.

[0013] Preferably, the first powder supply shaft and the second powder supply shaft are configured such that when they are rotated to a predetermined angle, the powder supply chamber A or the powder supply chamber B can drop powder downwards.

[0014] Preferably, the powder supply component includes a powder supply chamber A and a powder supply chamber B, which are located on the same side of the forming cylinder. The first powder supply shaft and the second powder supply shaft are configured to allow only powder supply chamber A or powder supply chamber B to be in the powder-feeding state at the same time.

[0015] Preferably, the first powder return chamber group is located below the first powder return area, and the second powder return chamber group is located below the second powder return area. The first powder return area is provided with a first powder drop channel, and the second powder return area is provided with a second powder drop channel.

[0016] Preferably, the two powder return compartments in the powder return compartment group include powder return compartment A and powder return compartment B, and the driving component is used to drive powder return compartment A or powder return compartment B to align with the bottom of the first powder drop channel or the second powder drop channel.

[0017] Preferably, the scraper component includes a scraper mounting frame, two temporary storage funnels disposed on the scraper mounting frame, and a scraper disposed below the scraper mounting frame. A powder discharge pipe is provided below the two temporary storage funnels, and a valve is provided on the powder discharge pipe. When the valve is opened, the powder in the temporary storage funnels can fall along the powder discharge pipe to one side of the scraper. The scraper can move relative to the scraper mounting frame so that it is on the left or right side of each powder discharge pipe.

[0018] Preferably, the amount of powder used to lay one layer of powder is defined as Q, and the capacity of the temporary storage funnel is greater than 2Q.

[0019] Preferably, a movable cover plate is provided above the temporary storage funnel, the cover plate being used to cover one of the temporary storage funnels.

[0020] Compared with the prior art, the advantages of this utility model are:

[0021] Through real-time linkage between the movable powder return bin and the powder supply bin, the powder return bin can be switched synchronously according to the current powder type. At the same time, the scraper component can achieve bidirectional powder scraping. When the scraper component scrapes powder in both directions, the position of the powder return bin can be dynamically adjusted according to the scraper direction to ensure that the powder falling and returning enters the corresponding powder return bin. There is no powder spillage, the powder supply and return efficiency is high, the purity is high, and it can be directly recycled and reused. In addition, the scraper component is designed to have the function of temporarily storing powder, which can realize bidirectional powder scraping in one drop, thereby improving processing efficiency. Attached Figure Description

[0022] The accompanying drawings are not intended to be drawn to scale. In the drawings, each identical or nearly identical component shown in the various figures may be denoted by the same reference numeral. For clarity, not every component is labeled in each figure. Embodiments of various aspects of the present invention will now be described by way of example and with reference to the accompanying drawings, wherein:

[0023] Figure 1 This is a schematic diagram of the structure of the first bidirectional powder feeding system based on multiple powders, as shown in the embodiment of this utility model;

[0024] Figure 2 This is a schematic diagram of the structure of the second bidirectional powder feeding system based on multiple powders, as shown in the embodiment of this utility model;

[0025] Figure 3 This is a schematic diagram of the scraper component shown in an embodiment of the present invention;

[0026] Figure 4 This is a schematic diagram showing the powder supply chamber A supplying powder to the scraper component according to an embodiment of the present invention;

[0027] Figure 5 This is a schematic diagram showing the scraper moving towards the powder discharge tube in an embodiment of the present invention;

[0028] Figure 6 This is a schematic diagram of the scraper component moving to the right to complete the scraping of the first powder A, as shown in this embodiment of the utility model;

[0029] Figure 7 This is a schematic diagram of powder falling on the right side of the scraper as shown in an embodiment of this utility model;

[0030] Figure 8This is a schematic diagram of the scraper component moving to the left to complete the scraping of the first powder A, as shown in this embodiment of the utility model;

[0031] Figure 9 This is a schematic diagram of powder falling from the left side of the scraper in an embodiment of this utility model;

[0032] Figure 10 This is a schematic diagram showing the powder supply chamber B supplying powder to the scraper component according to an embodiment of the present invention;

[0033] Figure 11 This is a schematic diagram of the second powder falling from the left side of the scraper in an embodiment of this utility model. Detailed Implementation

[0034] To better understand the technical content of this utility model, specific embodiments are provided below in conjunction with the accompanying drawings.

[0035] Combination Figure 1 and Figure 2 As shown, this utility model proposes a bidirectional powder feeding system based on multiple powders, including a powder spreading bin 100, a scraper component 10, a forming cylinder 20, a powder feeding component 30, a powder return component 40, and a controller.

[0036] The powder spreading chamber 100 is set with a predetermined protective atmosphere to form an environment for laser sintering powder, and the bottom of the powder spreading chamber 100 is provided with a powder scraping surface 101.

[0037] It should be understood that the powder-spreading chamber 100 is filled with an inert gas at a suitable pressure to prevent the powder from being oxidized during laser sintering.

[0038] The scraper component 10 is connected to a track on the inner wall of the powder spreading chamber 100 and can be driven to reciprocate along the first direction extending along the track against the powder spreading plane 101.

[0039] Optionally, the track not only provides guidance for the movement of the scraper component 10, but also drives the scraper component 10 to move to different positions on the surface of the track, especially to both sides of the forming cylinder 20, to wait for the powder to fall from the powder supply component 30, to complete the scraping, and to scrape the remaining powder to the powder return component 40.

[0040] The forming cylinder 20 is located below the powder scraping plane 101 of the powder spreading chamber 100 and communicates with the inner cavity of the powder spreading chamber 100. The forming cylinder 20 is provided with a forming substrate 21, which is configured to move upward or downward within the forming cylinder 20. The forming cylinder 20 is provided with a first powder return area 103 and a second powder return area 102 on both sides. Both the first powder return area 103 and the second powder return area 102 are provided with powder return channels.

[0041] Furthermore, the powder supply component 30 is used to quantitatively supply two or more types of powder to the scraper component 10, and the powder supply component 30 is located above the first powder return area 103 and / or the second powder return area 102.

[0042] Thus, when the powder supply component 30 delivers powder to the predetermined area (first powder return area 103 and / or second powder return area 102), the scraper component 10 receives the powder and scrapes it along the scraping plane 101, completing the layer-by-layer powder spreading through the layer-by-layer descent of the forming substrate 21 in the forming cylinder.

[0043] It should be understood that when each layer of powder is laid, there is excess powder that needs to be recycled after the current powder scraping is completed. Since the powder laying involves more than one type of powder, it is not conducive to the reuse of powder if the same recycling bin is used for recycling. Therefore, the powder recycling component 40 includes two powder recycling bin groups, which are located below the first powder recycling area 103 and the second powder recycling area 102, respectively. The powder recycling bin group includes two or more powder recycling bins and a drive component 43 that drives any one of the powder recycling bins to the corresponding position of the powder recycling channel.

[0044] Thus, when a certain type of powder is scraped, a corresponding powder return bin is used below the powder return channel to receive excess powder, making the powder in the powder return bin a single type, which is beneficial for later reuse. For example, the current powder return bin is connected to the powder supply component 30, and the powder after return can be directly used for powder supply.

[0045] In an optional embodiment, the drive component 43 is a linear track that can control any one of the multiple toner return compartments to be below the toner return channel.

[0046] In other embodiments, the drive component 43 may also be a circular track, such as a circular track surrounding the outside of the molding cylinder 20, which can control any one of the multiple powder return chambers on the track to be below a suitable powder return channel.

[0047] Furthermore, the controller is electrically connected to the scraper component 10, the drive component 43, and the powder supply component 30. The controller is configured to control the drive component 43 to operate according to the powder type of the current powder layer and the position of the scraper component 10, so that the powder return channel corresponding to the start and end positions of the scraper component 10 is located below the powder return hopper corresponding to the current powder type.

[0048] In this way, by controlling the movement of the powder return hopper, a powder return hopper matching the powder type can be used below the corresponding powder return channel to receive the powder according to the powder position and powder type when it falls, and a powder return hopper matching the powder type can be used below the corresponding powder return channel to receive the powder according to the powder type and the position of the end of the scraping process, thereby ensuring the consistency of powder supply and powder recovery.

[0049] Understandably, the powder supply component 30 is designed to provide different types and amounts of powder to the scraper component 10 at the appropriate location.

[0050] Combination Figure 1 As shown, in an optional embodiment, taking the powder supply component 30 providing two kinds of powder as an example, the powder supply component 30 includes a powder supply chamber A31 and a first powder supply shaft 33, a powder supply chamber B32 and a second powder supply shaft 34 disposed below the powder supply chamber A31. The powder supply chamber A31 is located on the first side of the forming cylinder 20 and the powder supply chamber B32 is located on the second side of the forming cylinder 20.

[0051] Among them, powder supply bin A31 is used to hold the first type of powder, and powder supply bin B32 is used to hold the second type of powder.

[0052] Furthermore, the first powder supply shaft 33 and the second powder supply shaft 34 are electrically connected to the controller. The controller is used to control the rotation state of the first powder supply shaft 33 and the second powder supply shaft 34. When the first powder supply shaft 33 or the second powder supply shaft 34 rotates to a predetermined angle, the powder supply chamber A31 or the powder supply chamber B32 can drop powder downwards.

[0053] Thus, when the scraper component 10 moves below the powder supply chamber A31, the first type of powder can be supplied to the scraper component 10 through the powder supply chamber A31, and when the scraper component 10 moves below the powder supply chamber B32, the second type of powder can be supplied to the scraper component 10 through the powder supply chamber B32.

[0054] Combination Figure 2 As shown, in other embodiments, taking the powder supply component 30 providing two types of powder as an example, the powder supply component 30 includes a powder supply chamber A31 and a powder supply chamber B32, which are located on the same side of the forming cylinder 20. The first powder supply shaft 33 and the second powder supply shaft 34 are configured to allow only the powder supply chamber A31 or the powder supply chamber B32 to be in the powder falling state at the same time.

[0055] Thus, the powder supply component 30 needs to provide two powder feeding amounts to the scraper component 10 at a time to meet the powder requirements of the bidirectional powder spreading of the scraper component 10. When the powder type for one round trip is one, the powder supply component 30 provides the scraper component 10 with twice the amount of powder. When the powder type for one round trip is two, the powder supply component 30 continuously provides the scraper component 10 with two types of powder, and the amount of each type of powder meets the requirements of one layer of powder spreading.

[0056] It should be understood that the toner supply component 30 includes, but is not limited to, two types of toner supply bins. The number of toner supply bins is set according to the requirements. For example, toner supply bin A and toner supply bin B are set on one side, and toner supply bin C and toner supply bin D are set on the other side. At the same time, the type of toner return bin is matched with the type of toner supply bin, and preferably twice the number of toner supply bins.

[0057] In the above embodiments, combined with Figure 1 and Figure 2 As shown, the first powder return chamber group is located below the first powder return area 103, and the second powder return chamber group is located below the second powder return area 102. The first powder return area 103 is provided with a first powder drop channel 401, and the second powder return area 102 is provided with a second powder drop channel 402.

[0058] Furthermore, the two toner return compartments in the toner return compartment group include toner return compartment A41 and toner return compartment B42, and the drive unit 43 is used to drive toner return compartment A41 or toner return compartment B42 to align below the first toner drop channel 401 or the second toner drop channel 402.

[0059] In this way, regardless of whether the scraper part 10 scrapes powder from left to right or from right to left, the excess powder will be received by the corresponding powder return chamber.

[0060] Specifically, in combination Figure 1 As shown, taking the first layer of powder to be applied as first powder A and the second layer as second powder B as an example, the scraper component 10 is initially in the left position (first powder return area 103). The powder supply chamber A31 in the powder supply component 30 provides the first powder A to the scraper component 10. At this time, the first powder drop channel 401 is below the powder return chamber A41, and the second powder drop channel 402 is also below the powder return chamber A41. The scraper component 10 scrapes the powder on the first layer, so that the first powder A covers the first layer of the molding substrate 21. The excess powder enters the powder return chamber A4 from the second powder drop channel 402. Then, the area below the first powder drop channel 401 and the second powder drop channel 402 is switched to the powder return chamber B42. The powder supply component 30 provides the second powder B to the scraper component 10. The scraper component 10 scrapes the powder on the second layer, so that the second powder B covers the second layer of the molding substrate 21. The excess powder falls from the first powder drop channel 401 into the powder return chamber B42.

[0061] In the above embodiments, the scraper component 10 includes a scraper mounting bracket 15, two temporary storage funnels 11 disposed on the scraper mounting bracket 15, and a scraper 16 disposed below the scraper mounting bracket 15.

[0062] Preferably, the amount of powder used to lay one layer of powder is defined as Q, and the capacity of the temporary storage funnel 11 is greater than 2Q.

[0063] Thus, the powder storage needs can be met by using two temporary storage funnels 11, and powder can be dropped in one go, completing bidirectional powder scraping.

[0064] For example, if the two layers of powder to be spread are either first powder A or second powder B, then the powder supply component 30 provides a single powder (first powder A or second powder B) to one of the temporary storage funnels 11, and the movement of the scraper mounting bracket 15 drives the scraper 16 to complete bidirectional powder scraping; if the first layer of the two layers of powder to be spread is first powder A and the second layer is second powder B, then the powder supply component 30 places first powder A into one of the temporary storage funnels 11 and second powder B into the other temporary storage funnel 11.

[0065] Furthermore, a powder discharge pipe 13 is provided below the two temporary storage funnels 11, and a valve 12 is provided on the powder discharge pipe 13. When the valve 12 is opened, the powder in the temporary storage funnel 11 can fall along the powder discharge pipe 13 to one side of the scraper 16. The scraper 16 can move relative to the scraper mounting bracket 15 so that it is on the left or right side of each powder discharge pipe 13.

[0066] Thus, by controlling the state of valve 12, the amount of powder falling from temporary storage funnel 11 to powder falling tube 13 can be controlled. Before powder falling, the position of scraper 16 is controlled according to the current position of scraper component 10 to ensure that the powder is on the side that scraper 16 will move.

[0067] Furthermore, a movable cover plate 14 is provided above the temporary storage funnel 11, which is used to cover one of the temporary storage funnels 11.

[0068] Thus, the temporary storage funnel 11 can be covered by the cover plate 14 to prevent another type of powder from entering the current temporary storage funnel 11 when it is being discharged.

[0069] In a specific embodiment, taking the case where both future layers are coated with the first powder A as an example.

[0070] Combination Figure 4 As shown, at this time, the powder spreading of the current layer is about to be completed. The powder type is the first powder A. The scraper component 10 is located on the left side. The first powder A is supplied to the scraper component 10 by the powder supply bin A31 on the left side. At this time, the powder return bin A41 moves to the bottom of the powder drop channel to collect the excess first powder A during the powder drop.

[0071] Combination Figure 5 As shown, the temporary storage funnel 11 on the right is covered by the cover plate 14 at this time, and the temporary storage funnel 11 on the left is below the powder supply chamber A31 and receives the first powder A falling from the powder supply chamber A31. Since the scraper component 10 needs to move to the right to spread powder, the scraper 16 moves to the left so that the powder falling pipe 13 is located on the right side of the scraper 16, and by controlling the opening and closing of the valve 12, the amount of powder falling is half the capacity of the temporary storage funnel 11.

[0072] Combination Figure 6 and Figure 7As shown, the scraper component 10 moves to the right. At the end of the scraper component 10, below the powder drop channel is the powder return chamber A41. When the scraper component 10 scrapes powder to the right, excess powder falls into the powder return chamber A41.

[0073] Combination Figure 8 and Figure 9 As shown, the scraper 16 moves to the right side of the powder drop tube 13, and then controls the remaining powder to fall by opening and closing the valve 12. The scraper component 10 moves from the right side to the left side to complete bidirectional powder scraping.

[0074] In other embodiments, the example is that the two future layers are alternately coated with first powder A and second powder B.

[0075] Combination Figure 4 As shown, at this time, the powder spreading of the current layer is about to be completed. The powder type is the first powder A. The scraper component 10 is located on the left side. The first powder A is supplied to the scraper component 10 by the powder supply bin A31 on the left side. At this time, the powder return bin A41 moves to the bottom of the powder drop channel to collect the excess first powder A during the powder drop.

[0076] Combination Figure 6 As shown, the scraper component 10 moves to the right. At the end of the scraper component 10, below the powder drop channel is the powder return chamber A41. When the scraper component 10 scrapes powder to the right, excess powder falls into the powder return chamber A41.

[0077] Combination Figure 10 As shown, the second powder B is supplied to the scraper component 10 through the powder supply bin B32 on the right. At this time, the powder return bin B42 moves to the bottom of the powder drop channel and recovers the excess second powder B during the powder drop through the powder return bin B42 on the right. Furthermore, when the scraper component 10 completes the spreading of the second powder B in the current powder layer, the excess second powder B is recovered through the powder return bin B42 on the left.

[0078] A powder feeding method based on the above-described bidirectional powder feeding system for multiple powders includes the following steps:

[0079] Step 1: Obtain the current position of the scraper component 10;

[0080] Step 2: The scraper component 10 completes the powder spreading in a bidirectional scraping manner. According to the type of powder required for the printing layer to be printed, the powder supply component 30 is controlled to supply the required powder to the scraper component 10 during the bidirectional scraping process.

[0081] The powder supplied by the powder supply component 30 to the doctor blade component 10 includes the powder of the current printing layer and / or the powder type and amount of the next printing layer;

[0082] During the powder supply process for the previous or next printing layer, at the powder drop point, the drive unit 43 drives the return powder hopper corresponding to the type of powder dropped to below the first powder drop channel 401 or the second powder drop channel 402. At the powder return point, the drive unit 43 drives the return powder hopper corresponding to the type of powder laid to below the first powder drop channel 401 or the second powder drop channel 402.

[0083] In an optional embodiment, in step 2, the printing layer to be printed can be the current printing layer or the current printing layer and the next printing layer. That is, the powder supply component 30 provides one or two layers of powder to the doctor blade component 10. In other words, the current layer can be printed by applying powder at one time, or two layers can be printed by applying powder at one time.

[0084] When powder is dispensed from the powder supply component 30, the return powder hopper below the powder dispensing channel at the current location of the powder supply component 30 needs to be matched with the type of powder being dispensed. When the scraper component 10 scrapes the powder,

[0085] Furthermore, in step 2, the amount of powder falling off the scraper component 10 before scraping the powder off the current printed layer is greater than the amount of powder in the current printed layer.

[0086] In this way, the amount of powder in the current printing layer is not insufficient, the powder spreading quality is ensured by the excess powder, and the difficulty of controlling the amount of powder falling during two printing processes with one powder falling is also reduced. Excess powder is collected through the corresponding powder return hopper.

[0087] In a specific embodiment, taking the case where both future layers are coated with the first powder A as an example.

[0088] Combination Figure 4 As shown, at this time, the powder spreading of the current layer is about to be completed. The powder type is the first powder A. The scraper component 10 is located on the left side. The first powder A is supplied to the scraper component 10 by the powder supply bin A31 on the left side. At this time, the powder return bin A41 moves to the bottom of the powder drop channel to collect the excess first powder A during the powder drop.

[0089] Combination Figure 5 As shown, the temporary storage funnel 11 on the right is covered by the cover plate 14 at this time, and the temporary storage funnel 11 on the left is below the powder supply chamber A31 and receives the first powder A falling from the powder supply chamber A31. Since the scraper component 10 needs to move to the right to spread powder, the scraper 16 moves to the left so that the powder falling pipe 13 is located on the right side of the scraper 16, and by controlling the opening and closing of the valve 12, the amount of powder falling is half the capacity of the temporary storage funnel 11.

[0090] Combination Figure 6 and Figure 7As shown, the scraper component 10 moves to the right. At the end of the scraper component 10, below the powder drop channel is the powder return chamber A41. When the scraper component 10 scrapes powder to the right, excess powder falls into the powder return chamber A41.

[0091] Combination Figure 8 and Figure 9 As shown, the scraper 16 moves to the right side of the powder drop tube 13, and then controls the remaining powder to fall by opening and closing the valve 12. The scraper component 10 moves from the right side to the left side to complete bidirectional powder scraping.

[0092] In other embodiments, the example is that the two future layers are alternately coated with first powder A and second powder B.

[0093] Combination Figure 4 As shown, at this time, the powder spreading of the current layer is about to be completed. The powder type is the first powder A. The scraper component 10 is located on the left side. The first powder A is supplied to the scraper component 10 by the powder supply bin A31 on the left side. At this time, the powder return bin A41 moves to the bottom of the powder drop channel to collect the excess first powder A during the powder drop.

[0094] Combination Figure 6 As shown, the scraper component 10 moves to the right. At the end of the scraper component 10, below the powder drop channel is the powder return chamber A41. When the scraper component 10 scrapes powder to the right, excess powder falls into the powder return chamber A41.

[0095] Combination Figure 10 and Figure 11 As shown, the second powder B is supplied to the scraper component 10 through the powder supply bin B32 on the right. At this time, the powder return bin B42 moves to the bottom of the powder drop channel and recovers the excess second powder B during the powder drop through the powder return bin B42 on the right. Furthermore, when the scraper component 10 completes the spreading of the second powder B in the current powder layer, the excess second powder B is recovered through the powder return bin B42 on the left.

[0096] Although the present invention has been disclosed above with reference to preferred embodiments, it is not intended to limit the present invention. Those skilled in the art to which this invention pertains can make various modifications and refinements without departing from the spirit and scope of the present invention. Therefore, the scope of protection of this invention shall be determined by the claims.

Claims

1. A bidirectional powder feeding system based on multiple powders, characterized in that, include: The powder spreading chamber (100) is configured with a predetermined protective atmosphere to form an environment for laser sintering powder, and the bottom of the powder spreading chamber (100) is provided with a powder scraping surface (101). The scraper component (10) is connected to the track on the inner wall of the powder spreading chamber (100) and can be driven to reciprocate along the first direction of the track against the powder spreading plane (101) for bidirectional powder spreading; A forming cylinder (20) is disposed below the powder scraping plane (101) of the powder spreading chamber (100) and communicates with the inner cavity of the powder spreading chamber (100). A forming substrate (21) is provided inside the forming cylinder (20). The forming substrate (21) is configured to move upward or downward inside the forming cylinder (20). A first powder return area (103) and a second powder return area (102) are respectively provided on both sides of the forming cylinder (20). Both the first powder return area (103) and the second powder return area (102) are provided with powder return channels. A powder supply component (30) is used to quantitatively supply two or more types of powder to the scraper component (10), the powder supply component (30) being located above the first powder return area (103) and / or the second powder return area (102); The powder return component (40) includes two powder return chamber groups, which are located below the first powder return area (103) and the second powder return area (102), respectively; The powder return chamber group includes two or more powder return chambers and a drive component (43) for driving any one of the powder return chambers to the corresponding position of the powder return channel. The drive component (43) is used to drive the powder return chamber to move so that the powder return channel below the starting position and ending position of the scraper component (10) is the powder return chamber corresponding to the current powder type.

2. The bidirectional powder feeding system based on multiple powders according to claim 1, characterized in that, The powder supply component (30) includes a powder supply chamber A (31), a first powder supply shaft (33) disposed below the powder supply chamber A (31), a powder supply chamber B (32), and a second powder supply shaft (34) disposed below the powder supply chamber B (32). The powder supply chamber A (31) is located on the first side of the forming cylinder (20), and the powder supply chamber B (32) is located on the second side of the forming cylinder (20).

3. The bidirectional powder feeding system based on multiple powders according to claim 2, characterized in that, When the first powder supply shaft (33) and the second powder supply shaft (34) are rotated to a predetermined angle, the powder supply chamber A (31) or the powder supply chamber B (32) can drop powder downwards.

4. The bidirectional powder feeding system based on multiple powders according to claim 2, characterized in that, The powder supply component (30) includes a powder supply chamber A (31) and a powder supply chamber B (32). The powder supply chamber A (31) and the powder supply chamber B (32) are located on the same side of the forming cylinder (20). The first powder supply shaft (33) and the second powder supply shaft (34) are configured to allow only the powder supply chamber A (31) or the powder supply chamber B (32) to be in the powder dropping state at the same time.

5. The bidirectional powder feeding system based on multiple powders according to claim 1, characterized in that, The first powder return chamber group is located below the first powder return area (103), and the second powder return chamber group is located below the second powder return area (102). The first powder return area (103) is provided with a first powder drop channel (401), and the second powder return area (102) is provided with a second powder drop channel (402).

6. The bidirectional powder feeding system based on multiple powders according to claim 5, characterized in that, The two powder return compartments in the powder return compartment group include powder return compartment A (41) and powder return compartment B (42). The driving component (43) is used to drive powder return compartment A (41) or powder return compartment B (42) to be aligned with the first powder drop channel (401) or the second powder drop channel (402).

7. The bidirectional powder feeding system based on multiple powders according to any one of claims 1-5, characterized in that, The scraper component (10) includes a scraper mounting bracket (15), two temporary storage funnels (11) disposed on the scraper mounting bracket (15), and a scraper (16) disposed below the scraper mounting bracket (15). A powder drop tube (13) is provided below the two temporary storage funnels (11), and a valve (12) is provided on the powder drop tube (13). When the valve (12) is opened, the powder in the temporary storage funnels (11) can fall along the powder drop tube (13) to one side of the scraper (16). The scraper (16) can move relative to the scraper mounting bracket (15) so that it is on the left or right side of each powder drop tube (13).

8. The bidirectional powder feeding system based on multiple powders according to claim 7, characterized in that, The amount of powder used to lay a layer of powder is defined as Q, and the capacity of the temporary storage funnel (11) is greater than 2Q.

9. The bidirectional powder feeding system based on multiple powders according to claim 7, characterized in that, A movable cover plate (14) is provided above the temporary storage funnel (11), the cover plate (14) being used to cover one of the temporary storage funnels (11).

10. The bidirectional powder feeding system based on multiple powders according to claim 1, characterized in that, The drive component (43) includes a linear track or a circular track.

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