Working cavity with wind shield structure

Abstract

The utility model discloses a working cavity with a wind shield structure, relates to the technical field of additive manufacturing, and aims to solve the problems that the performance quality of a printed workpiece is affected, and the workpiece is unqualified and scrapped, The working cavity comprises a working cavity front door and a working cavity frame which are connected with each other, a powder laying guide rail is arranged in the working cavity frame, a powder laying scraper is arranged below the powder laying guide rail, an upper air blowing opening and a lower air blowing opening are formed in the interior and the bottom of the working cavity frame respectively, and a front transparent wind shield and a rear wind shield are arranged on the two sides of the upper air blowing opening and the two sides of the lower air blowing opening respectively.

Description

Technical Field

[0001] The utility model relates to the technical field of additive manufacturing, and in particular to a working cavity with a windshield structure. Background Art

[0002] Additive manufacturing technology is an advanced manufacturing technology with distinctive characteristics such as digital manufacturing, high flexibility and adaptability, direct CAD model drive, fast, and rich and diverse material types. Since it is not limited by the complexity of the part shape and does not require any tooling and molds, it has a very wide range of applications. Selective Laser Melting (SLM) is one of the additive manufacturing technologies that has developed rapidly in recent years. It uses powder materials as raw materials and uses lasers to scan the cross-section of three-dimensional entities layer by layer to complete prototype manufacturing. Its basic working process is: the powder feeding device delivers a certain amount of powder to the working platform surface, the powder spreading device spreads a layer of powder material on the bottom plate of the forming cylinder or the upper surface of the formed part, and the laser galvanometer system controls the laser to scan the solid part powder layer according to the cross-sectional profile of the layer with an approximately constant spot size and beam energy, so that the powder melts and bonds with the formed part below; when a layer of cross section is sintered, the working platform drops a layer of thickness, and the powder spreading device spreads a layer of uniform and dense powder on it, and scans and sinters a new layer of cross section, and after several layers of scanning and superposition, the entire prototype manufacturing is completed.

[0003] During the sintering process of the above-mentioned selective laser melting equipment, waste slag splashes will inevitably be generated at the upper end of the powder in the molding area. These splashes will have a great impact on the performance of the molded workpiece. The existing design is to arrange air blowing and air suction ports on both sides of the molding area, so as to form a flowing protective airflow above the molding area, and the splashes are taken away by the airflow. Due to the structural characteristics of the working chamber itself, such as the scraper needs to move back and forth to spread powder and the front side needs to reserve a maintenance operation observation area, the traditional design of the molding chamber does not have windshields on the front and back sides or the windshield design does not completely close the environment, resulting in the wind field in the front and rear edge areas of the molding format easily diffusing outward, which will relatively lead to the wind field fluidity is not stable enough, and the waste slag splashes at the front and rear edge positions cannot be completely taken away, thereby affecting the performance quality of the printed workpiece in this area, and in severe cases, even causing the workpiece to be unqualified and scrapped. Utility Model Content

[0004] In view of the above-mentioned deficiencies in the prior art, the purpose of the present application is to provide a working chamber with a windshield structure for additive manufacturing, which includes a working chamber front door and a working chamber frame that are connected to each other, a powder laying guide rail is provided inside the working chamber frame, a powder laying scraper is provided below the powder laying guide rail, an upper air outlet and a lower air outlet are provided inside and at the bottom of the working chamber frame, and a front transparent windshield and a rear windshield are provided on both sides of the upper air outlet and the lower air outlet, respectively.

[0005] Preferably, the upper end of the front transparent windshield plate is higher than the upper end of the upper air outlet, and the lower ends of the front transparent windshield plate and the rear windshield plate are both lower than the lower end of the lower air outlet.

[0006] Preferably, the front transparent windshield plate and the rear windshield plate are connected to the working cavity frame by bolts.

[0007] Preferably, it also includes a movable wind shield, which is installed on the rear wind shield through a butterfly hinge, the lower end height of the movable wind shield is lower than the lower end height of the lower air outlet, and the movable wind shield can rotate with the butterfly hinge as the center of the circle.

[0008] Preferably, a movable windshield is further included, and a cylinder is installed on one side of the front transparent windshield and the rear windshield, and the movable windshield is connected to the cylinder.

[0009] Preferably, it also includes a movable windshield plate, which has a bent structure and is installed in front of and behind the powder spreading scraper.

[0010] Preferably, there are multiple options for the structural shape of the movable windshield.

[0011] The beneficial technical effects of the utility model are:

[0012] It can effectively ensure the stability of the wind flow at the upper end of the molding area without affecting the normal powder spreading movement of the powder spreading scraper and observing the printing condition, so that waste slag splashes will not affect the printed workpiece, and ultimately improve the performance quality of the printed workpiece. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 The utility model is a schematic cross-sectional side view of the interior of the movable windshield of the flip structure.

[0014] Figure 2 for Figure 1 A partial enlarged schematic diagram in the middle.

[0015] Figure 3 The utility model is a schematic cross-sectional side view of the interior of the movable windshield plate of the utility model which is a vertically movable structure.

[0016] Figure 4 for Figure 1 A partial enlarged schematic diagram of point B in the middle.

[0017] Figure 5 The utility model is a schematic cross-sectional side view of the interior of a movable windshield plate that moves forward and backward.

[0018] Figure numerals: 1. front door of working chamber, 2. frame of working chamber, 3. upper air outlet, 4. powder spreading scraper, 5. powder spreading guide rail, 6. lower air outlet, 7. butterfly nut, 8. front transparent wind shield, 9. rear wind shield, 10 butterfly hinge, 11. movable wind shield. DETAILED DESCRIPTION

[0019] In order to facilitate the understanding of the present application, the present application will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present application are given in the drawings. However, the present application can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the disclosure of the present application more thoroughly and comprehensively understood.

[0020] like Figure 1-Figure 2 As shown, a working chamber with a windshield structure comprises a working chamber front door 1 and a working chamber frame 2 which are connected to each other. A powder spreading guide rail 5 is provided inside the working chamber frame 2, a powder spreading scraper 4 is provided below the powder spreading guide rail 5, and an upper air outlet 3 and a lower air outlet 6 are provided inside and at the bottom of the working chamber frame 2, respectively. In order to improve the flow performance of the wind field and improve the performance quality of the printed workpiece, a front transparent windshield 8, a rear windshield 9, and a movable windshield 11 are added on both sides of the upper air outlet 3 and the lower air outlet 6, respectively.

[0021] The front transparent windshield 8 and the rear windshield 9 need to wrap the entire upper air outlet 3 and the lower air outlet 6. The lower end height of the movable windshield 11 should be lower than the lower end height of the lower air outlet 6, and the height difference h is preferably about 10 mm. The height h1 of the movable windshield needs to be greater than the scraper height h2 to ensure that the scraper can pass smoothly, and the value of (h2-h1) is preferably 10 mm to 20 mm, which can be adjusted according to actual conditions.

[0022] The front transparent windshield 8 is made of a transparent plastic plate, such as an acrylic plate, a PET plate, etc., and needs to have a certain high temperature resistance to prevent deformation caused by excessive temperature in the working chamber, and facilitate observation from the front door 1 of the working chamber during the sintering process. Since components such as the top galvanometer window mirror in the working chamber require frequent maintenance, the front transparent windshield 8 needs to be removed frequently. In order to facilitate disassembly and assembly, studs are directly installed on both sides of the working chamber, and a connecting bent sheet metal (not shown in the figure) is installed above the working chamber frame 2. The corresponding openings in the front transparent windshield 8 are inserted into the corresponding studs, and finally the butterfly nuts 7 are screwed on the studs to tighten them. The butterfly nuts 7 are convenient for tightening, and no additional tools such as wrenches are required.

[0023] The molding area is the area surrounded by the suction port, the upper air outlet 3, the lower air outlet 6, the front transparent windshield 8, and the rear windshield 9 inside the working chamber. The lower end of the molding area is located above the powder scraper 4 at the lower end of the working chamber, and the movable windshield 11 is installed on the rear windshield 9 through a butterfly hinge 10 because the powder scraper 4 will continue to spread powder back and forth. When the powder scraper 4 passes through this area, it will directly contact the movable windshield 11 and flip the movable windshield 11 up to ensure that it does not affect the movement of the powder scraper 4. When the powder scraper 4 leaves, the movable windshield 11 will return to the vertical position by itself due to its own weight, keeping the entire wind field area in a closed state, making the fluidity of the entire wind field more uniform and stable, ensuring that all the splashes of sintering waste slag can be effectively taken away from the suction port, ensuring that this set of windshield design will not have any impact on the entire printing equipment, and at the same time, it can effectively improve the flow performance of the wind field, so that the performance and quality of the printed workpiece are better.

[0024] When in use, the rear windshield 9 is fixed, and the two connecting pieces of the butterfly hinge 10 can be rotated almost 360° along the rotation axis (similar to the hinge for a door). After the movable windshield 11 is installed through the butterfly hinge 10, the movable windshield 11 can rotate along the rotation axis of the butterfly hinge 10. When the movable windshield 11 is not subjected to external force, it is in a vertical downward position, that is, it can just completely close the front and back of the molding area. When the powder spreading scraper 4 moves over, the scraper will collide with the movable windshield 11. At this time, the movable windshield 11 will be flipped along the rotation axis of the butterfly hinge 10 under the external force, until the powder spreading scraper 4 completely leaves this area, that is, when the powder spreading scraper 4 is no longer in contact with the movable windshield 11, the movable windshield 11 will return to the vertical downward state due to its own gravity, closing the molding area, and so on.

[0025] There are many options for the structure of the movable wind deflector 11.

[0026] like Figure 3-Figure 4As shown, the cylinder 12 is connected to the movable windshield 11. When the powder scraper 4 moves, the cylinder 12 will drive the movable windshield 11 to move upward to ensure that the lower end gap can smoothly allow the powder scraper 4 to pass through. When the powder scraper 4 moves into place for sintering printing, the cylinder 12 will drive the movable windshield 11 to move downward to ensure a closed environment;

[0027] like Figure 5 As shown, movable windshields 11 are installed in front and behind the powder spreading scraper 4, and the movable windshield 11 is in a bent shape that fits the powder spreading scraper 4. And the upper end of the movable windshield 11 is close to the height of the lower end notches of the front transparent windshield 8 and the rear windshield 9. When the powder spreading scraper 4 moves to the front and rear extreme positions, the movable windshield 11 is just flush with the front transparent windshield 8 and the rear windshield 9, which also ensures a closed environment during sintering.

[0028] Regardless of which of the above solutions, including solutions not mentioned in this patent, their purposes and functions are the same, and the specific installation method can be selected according to actual conditions.

[0029] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced with equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

[0030] In the description of the present invention, the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inner", "outer" and the like indicating directions or positional relationships are based on the directions or positional relationships shown in the drawings, which are only for the convenience of description, and do not indicate or imply that the device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. In addition, the terms "first", "second", and "third" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance.

[0031] In addition, it should be noted that in the description of the present invention, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" 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 those skilled in the art, the specific meanings of the above terms in the present invention can be understood according to the specific circumstances.

[0032] The term "comprise" or any other similar term is intended to cover a non-exclusive inclusion, such that a process, article, or apparatus / device that includes a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, article, or apparatus / device.

[0033] So far, the technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it is easy for those skilled in the art to understand that the protection scope of the present invention is obviously not limited to these specific embodiments. Without departing from the principle of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will fall within the protection scope of the present invention.

Claims

1. A working chamber with a windshield structure, comprising a working chamber front door (1) and a working chamber frame (2) connected to each other, a powder spreading guide rail (5) being provided inside the working chamber frame (2), a powder spreading scraper (4) being provided below the powder spreading guide rail (5), an upper blowing port (3) and a lower blowing port (6) being provided inside and at the bottom of the working chamber frame (2), characterized in that: A front transparent windshield (8) and a rear transparent windshield (9) are respectively provided on both sides of the upper air outlet (3) and the lower air outlet (6).

2. The working chamber with a windshield structure according to claim 1, characterized in that: The upper end of the front transparent windshield (8) is higher than the upper end of the upper air outlet (3), and the lower ends of the front transparent windshield (8) and the rear windshield (9) are both lower than the lower end of the lower air outlet (6).

3. The working chamber with a windshield structure according to claim 1, characterized in that: The front transparent windshield (8) and the rear windshield (9) are connected to the working chamber frame (2) via bolts.

4. The working chamber with a windshield structure according to claim 1, characterized in that: It also comprises a movable wind shield (11), wherein the movable wind shield (11) is mounted on the rear wind shield (9) via a butterfly hinge (10), the lower end height of the movable wind shield (11) is lower than the lower end height of the lower air outlet (6), and the movable wind shield (11) is rotatable with the butterfly hinge (10) as the center of the circle.

5. The working chamber with a windshield structure according to claim 1, characterized in that: It also comprises a movable windshield (11), a cylinder (12) being installed on one side of the front transparent windshield (8) and the rear windshield (9), and the movable windshield (11) is connected to the cylinder (12).

6. The working chamber with a windshield structure according to claim 1, characterized in that: It also comprises a movable windshield (11), the movable windshield (11) having a bent structure and being installed in front of and behind the powder spreading scraper (4).

7. The working chamber with a windshield structure according to claim 4, 5 or 6, characterized in that: There are multiple options for the structural shape of the movable wind deflector (11).

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