Cantilever single-scraper bidirectional powder spreading mechanism for selective laser melting forming

Abstract

The cantilever single-scraper two-way powder spreading mechanism comprises a scraper frame assembling assembly and a limiting block assembly, the scraper frame assembling assembly is located above a forming platform in a forming chamber, and the limiting block assembly is located on one side of the forming platform; the scraper frame assembly component comprises a scraper frame body, a powder distributor, a powder containing plate, a scraper and a scraper pressing plate, a one-way powder laying and falling position and a two-way powder laying and falling position are arranged on the scraper frame body, the powder distributor is installed on the scraper frame body, a one-way powder falling channel is arranged in the scraper frame body, and the two-way powder falling channel is communicated with the one-way powder falling channel. The one-way powder falling channel is communicated with the one-way powder laying and falling position and one powder distributing cavity of the powder distributor, and the other powder distributing cavity of the powder distributor is matched with the scraper frame body to form the other powder falling channel. By adjusting the powder receiving position, the one-way and two-way powder spreading state can be easily switched under the conditions that a mechanism is not replaced and a cabin door is not opened, halfway stopping of printing is avoided, the operation time is saved, and the printing efficiency is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of additive manufacturing, and in particular relates to a cantilever single-scraper bidirectional powder spreading mechanism for laser selective melting forming. Background Art

[0002] Additive manufacturing (also known as laser selective melting or metal 3D printing) technology is a new processing method that has emerged in recent years. The raw materials used in this technology are all powders of tens to hundreds of microns. During the forming process, the powder is evenly spread on the forming substrate through a powder supply device and a powder spreading device, and then a laser or other energy source is used to melt the powder in a specific geometric shape area on the surface to produce a metallurgical bond, and finally the parts are grown layer by layer to achieve a three-dimensional forming process.

[0003] During the laser selective melting process, due to the growth angle of the parts, one-way powder printing is required in some cases. Except for such special cases, two-way powder printing can greatly save printing time. The traditional double-scraper two-way powder spreading mechanism has the problem that the two scrapers are difficult to level each other, and one side of the scraper needs to be removed when switching to one-way powder spreading. Removing the scraper requires opening the hatch to change the mechanism, which is inconvenient to operate. In addition, during two-way powder spreading, there are splashing particles in the return powder that affect the printing effect. Summary of the invention

[0004] In order to solve the problems existing in the prior art, the present invention proposes a cantilever single-scraper bidirectional powder spreading mechanism for laser selective melting forming. This mechanism is a single-scraper bidirectional powder spreading mechanism that perfectly solves the above problems. The leveling of a single scraper is simple and only requires one leveling. During the printing process, the powder receiving position can be adjusted at any time according to the angle of the part to achieve switching between single and bidirectional powder spreading. There is no need to change the mechanism or open the cabin door, which avoids stopping the printing midway, saves operation time, and improves printing efficiency. When receiving the powder, the returning powder is blocked by the powder collecting plate and does not pass through the powder bed, and there is no problem of powder contamination.

[0005] The present invention is implemented as follows: a cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming comprises a scraper frame assembly component and a limit block assembly, wherein the scraper frame assembly component is located above a forming platform in a forming chamber, and the limit block assembly is located on one side of the forming platform, and the limit block assembly is on a different side from the powder dropping mechanism;

[0006] The scraper frame assembly assembly comprises a scraper frame body, a powder divider, a powder collecting plate, a scraper, and a scraper pressing plate. The scraper frame body is provided with two powder dropping positions, a one-way powder spreading and dropping position and a two-way powder spreading and dropping position. The powder divider is installed on the scraper frame body. The powder divider is a structure in which powder dropping chambers are cross-arranged on the left and right and stacked in sequence. A one-way powder dropping channel is provided in the scraper frame body. The one-way powder dropping channel is respectively connected with the one-way powder spreading and dropping position and one of the powder dropping chambers of the powder divider. The other powder dropping chamber of the powder divider cooperates with the scraper frame body to form another powder dropping channel. The scraper is installed at the bottom of the scraper frame body and is located between the two powder dropping channels.

[0007] When the powder dropping mechanism outlet is aligned with the one-way powder dropping position, the powder falls into the one-way powder dropping channel to achieve one-way powder spreading and printing; when the powder dropping mechanism outlet is aligned with the two-way powder spreading and printing position, the powder falls into two powder separation chambers respectively, and the amount of powder falling into both sides is the same. The powder in one powder separation chamber falls into the one-way powder dropping channel, and the powder in the other powder separation chamber can be caught by the powder catching plate to achieve two-way powder spreading and printing;

[0008] When the scraper frame assembly moves to the point where the powder collecting plate contacts the limit block assembly, the powder collecting plate can be separated from the outlet of another powder dropping channel to allow the powder to fall. When the powder collecting plate is separated from the limit block assembly, the powder collecting plate can automatically return to its original position.

[0009] In the above technical solution, preferably, the powder collecting plate is rotatably installed at the outlet of another powder falling channel. When the powder collecting plate is not subjected to force, it relies on gravity to maintain a natural state and blocks the outlet of the powder falling channel. When it moves to the powder spreading stop position, the powder collecting plate of the limit block assembly rotates to open the outlet of the powder falling channel, and the powder falls.

[0010] In the above technical solution, it is further preferred that the powder collecting plate is hung on the rotating shafts on the front and rear sides of the scraper frame body through a connecting plate.

[0011] In the above technical solution, it is further preferred that a stop plate is provided on the side of the powder collecting plate away from the limiting block assembly, so that the powder collecting plate can be quickly and stably restored to its original position.

[0012] In the above technical solution, preferably, the limit block assembly includes at least one limit block, and the limit block is installed at the powder spreading stop position of the forming platform.

[0013] In the above technical solution, preferably, the scraper is installed at the bottom of the scraper frame through a scraper pressing plate.

[0014] The advantages and positive effects of the present invention are:

[0015] 1. The cantilever single scraper bidirectional powder spreading mechanism of the present invention has a single scraper that is easy to level and only needs to be leveled once. The powder receiving position can be adjusted at any time according to the angle of the part during printing. By adjusting the powder receiving position, the single and bidirectional powder spreading states can be easily switched without changing the mechanism or opening the cabin door, thus avoiding stopping midway in printing, saving operation time, and improving printing efficiency.

[0016] 2. The cantilever single scraper bidirectional powder spreading mechanism of the present invention uses the powder-catching plate to catch the powder on the other side of the return trip. At the stop position, the limit block pushes the powder-catching plate away to let the powder fall, and the powder is spread in the reverse direction. The powder does not pass through the powder bed and there is no problem of powder contamination.

[0017] 3. The cantilever single-scraper bidirectional powder spreading mechanism of the present invention can automatically swing back due to the gravity of the powder collecting plate, thereby realizing switching of the powder collecting plate state without being subjected to impact force, thereby avoiding the problem that the terminal end of the cantilever scraper cannot be subjected to impact force for a long time due to the fact that the terminal end is not fixed; the mechanism runs without resistance and collision, and is therefore suitable for the use scenarios of the cantilever scraper. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a structural schematic diagram of a cantilever single scraper bidirectional powder spreading mechanism installed in a forming chamber provided by an embodiment of the present invention;

[0019] Figure 2 is a three-dimensional diagram of a scraper holder assembly component provided by an embodiment of the present invention;

[0020] Figure 3 is a side view of a scraper holder assembly provided by an embodiment of the present invention;

[0021] Figure 4 yes Figure 3 AA section view;

[0022] Figure 5 It is a cross-sectional view of another part of the scraper frame assembly component provided by an embodiment of the present invention.

[0023] In the figure: 1. scraper frame assembly; 2. limit block assembly; 3. scraper frame; 31. one-way powder spreading and powder dropping position; 32. two-way powder spreading and powder dropping position; 33. one-way powder dropping channel; 4. powder divider; 41. powder dividing chamber; 5. powder collecting plate; 51. stop plate; 6. rotating shaft; 7. connecting plate; 8. scraper; 9. scraper pressure plate; 10. forming platform; 11. powder dropping mechanism. DETAILED DESCRIPTION

[0024] In order to further understand the content, features and effects of the present invention, the following embodiments are given as examples and described in detail with reference to the accompanying drawings:

[0025] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by the terms "upper", "lower", "front", "back", "left", "right", "inside", "outside", etc. are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore cannot be understood as a limitation on the present invention.

[0026] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0027] See also Figure 1 to Figure 5 An embodiment of the present invention provides a cantilever single-scraper bidirectional powder spreading mechanism for laser selective melting forming, comprising a scraper frame assembly component and a limit block assembly, wherein the scraper frame assembly component is located above a forming platform in a forming chamber, and the limit block assembly is located on one side of the forming platform, on a different side from the powder dropping mechanism.

[0028] The scraper frame assembly component includes a scraper frame body, a powder separator, a powder collecting plate, a scraper, and a scraper pressure plate. The scraper frame body is provided with two powder dropping positions, a one-way powder spreading and dropping position and a two-way powder spreading and dropping position. The powder separator is installed on the scraper frame body. The powder separator is a structure with powder dropping chambers crosswise arranged on the left and right and stacked in sequence. A one-way powder dropping channel is provided in the scraper frame body. The one-way powder dropping channel is respectively connected with the one-way powder spreading and dropping position and one of the powder dropping chambers of the powder separator. The other powder dropping chamber of the powder separator cooperates with the scraper frame body to form another powder dropping channel. The scraper is installed at the bottom of the scraper frame body and is located between the two powder dropping channels.

[0029] When the powder dropping mechanism outlet is aligned with the one-way powder spreading and dropping position, the powder falls into the one-way powder dropping channel to realize one-way powder spreading and printing; when the powder dropping mechanism outlet is aligned with the two-way powder spreading and dropping position, the powder falls into two powder dividing chambers respectively, and the amount of powder falling on both sides is the same. The powder in one powder dividing chamber falls into the one-way powder dropping channel, and the powder in the other powder dividing chamber can be caught by the powder catching plate and will not fall, thereby realizing two-way powder spreading and printing.

[0030] When the scraper frame assembly moves to the point where the powder collecting plate contacts the limit block assembly, the powder collecting plate can be separated from the outlet of another powder dropping channel to allow the powder to fall. When the powder collecting plate is separated from the limit block assembly, the powder collecting plate can automatically return to its original position.

[0031] Specifically, Figure 2 As shown, the powder collecting plate is hung on the rotating shafts on the front and rear sides of the scraper frame body through the connecting plate. The powder collecting plate is rotatably installed at the outlet of another powder dropping channel. When the powder collecting plate is not subjected to force, it relies on gravity to maintain a natural state and blocks the outlet of the powder dropping channel. When it moves to the powder spreading stop position, the powder collecting plate is blocked by the limit block assembly to rotate and open the outlet of the powder dropping channel, and the powder falls. When the scraper frame assembly assembly returns, the collecting plate automatically falls back.

[0032] A stop plate is arranged on one side of the powder collecting plate away from the limiting block assembly, so that the powder collecting plate can be quickly and stably restored to its original position.

[0033] The limit block assembly includes at least one limit block, which is installed at the powder spreading stop position of the forming platform. When the powder collecting plate moves to the powder spreading stop position, the powder collecting plate contacts the limit block, so that the powder collecting plate rotates to drop the powder, and after the powder collecting plate separates from the limit block, the powder collecting plate automatically swings back to the original position by gravity.

[0034] The scraper is installed at the bottom of the scraper frame body through a scraper pressing plate, and the installation and fixing are convenient.

[0035] The present invention can easily switch between single- and double-way powder spreading states without changing the mechanism or opening the cabin door by adjusting the powder receiving position; the mechanism holds the powder on the other side through the powder holding plate, and at the stop position, the limit block pushes the powder holding plate open to let the powder fall, and the powder is spread by reverse movement; the mechanism runs without resistance and collision, so it is suitable for the use of a cantilever scraper.

[0036] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. Any simple modification, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are within the scope of the technical solution of the present invention.

Claims

1. A cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming, characterized in that: It includes a scraper frame assembly component and a limit block component, wherein the scraper frame assembly component is located above the forming platform in the forming chamber, and the limit block component is located on one side of the forming platform, and the limit block component is on a different side from the powder dropping mechanism; The scraper frame assembly assembly comprises a scraper frame body, a powder divider, a powder collecting plate, a scraper, and a scraper pressing plate. The scraper frame body is provided with two powder dropping positions, a one-way powder spreading and dropping position and a two-way powder spreading and dropping position. The powder divider is installed on the scraper frame body. The powder divider is a structure in which powder dropping chambers are cross-arranged on the left and right and stacked in sequence. A one-way powder dropping channel is provided in the scraper frame body. The one-way powder dropping channel is respectively connected with the one-way powder spreading and dropping position and one of the powder dropping chambers of the powder divider. The other powder dropping chamber of the powder divider cooperates with the scraper frame body to form another powder dropping channel. The scraper is installed at the bottom of the scraper frame body and is located between the two powder dropping channels. When the powder dropping mechanism outlet is aligned with the one-way powder dropping position, the powder falls into the one-way powder dropping channel to achieve one-way powder spreading and printing; when the powder dropping mechanism outlet is aligned with the two-way powder spreading and printing position, the powder falls into two powder separation chambers respectively, and the amount of powder falling into both sides is the same. The powder in one powder separation chamber falls into the one-way powder dropping channel, and the powder in the other powder separation chamber can be caught by the powder catching plate to achieve two-way powder spreading and printing; When the scraper frame assembly moves to the point where the powder collecting plate contacts the limit block assembly, the powder collecting plate can be separated from the outlet of another powder dropping channel to allow the powder to fall. When the powder collecting plate is separated from the limit block assembly, the powder collecting plate can automatically return to its original position.

2. The cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming according to claim 1 is also characterized in that: The powder collecting plate is rotatably installed at the outlet of another powder falling channel. When the powder collecting plate is not subjected to force, it relies on gravity to maintain a natural state and blocks the outlet of the powder falling channel. When it moves to the powder spreading stop position, the blocking powder collecting plate of the limit block assembly rotates to open the outlet of the powder falling channel, and powder falls.

3. The cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming according to claim 2 is also characterized in that: The powder collecting plate is hung on the rotating shafts at the front and rear sides of the scraper frame body through a connecting plate.

4. The cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming according to claim 2 is also characterized in that: A stop plate is arranged on one side of the powder collecting plate away from the limiting block assembly, so that the powder collecting plate can be quickly and stably restored to its original position.

5. The cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming according to claim 1 is also characterized in that: The limit block assembly includes at least one limit block, and the limit block is installed at the powder spreading stop position of the forming platform.

6. The cantilever single scraper bidirectional powder spreading mechanism for laser selective melting forming according to claim 1 is also characterized in that: The scraper is installed at the bottom of the scraper frame body through a scraper pressing plate.

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