A metal powder spreading device for additive manufacturing of rocket engine thrust chamber

Abstract

The present invention discloses a metal powder spreading device for additive manufacturing of a rocket engine thrust chamber, and relates to the field of additive manufacturing technology. It comprises a body, a mounting seat is provided on the inner wall of the body cavity through a track sliding, and a powder spreading head is connected to the bottom of the mounting seat through a cylinder; it also comprises a powder feeding pipe, the powder feeding pipe is fixed through the top of the powder spreading head, the powder feeding pipe is connected to the powder feeding mechanism, the top area of ​​the powder spreading chamber is connected to a guide mesh plate through a first electric push rod, the bottom of the guide mesh plate is fixed with a sealing plate through a connecting rod, the sealing plate is provided at the bottom opening of the powder spreading chamber, and an auxiliary spreading strip is provided vertically slidingly in the mounting sleeve, a pressure plate is fixed to the bottom of the auxiliary spreading strip, and the pressure plate is located on the sealing plate. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber ensures the uniformity of powder spreading in the longitudinal direction, avoids powder agglomeration, and improves the powder spreading efficiency in conjunction with vibration.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a metal powder spreading device for additive manufacturing of a rocket engine thrust chamber. Background Art

[0002] The development direction of liquid rocket engines is high reliability, low cost, reuse and short development cycle. The thrust chamber operates in harsh environments such as high temperature, high pressure and large heat flux, and must withstand extreme pressure and temperature gradients. The improvement of engine performance will inevitably bring a more severe working environment to the thrust chamber. The mass of the thrust chamber generally accounts for more than 40% of the total mass of the entire engine. It has a complex structure and many parts, and has extremely high requirements in manufacturing precision, consistency, stability and reliability. Traditional large-sized thrust chambers are composed of hundreds or thousands of parts. Its production and manufacturing process involves mechanical processing, welding, inspection, testing and other links. Not only is the production cycle long, but some steps are difficult to detect, affecting product reliability. Advanced thrust chamber technology inevitably has a variety of materials and complex structures, which will bring difficulties to research and development and production.

[0003] Additive manufacturing technology has great advantages in complex structure molding, multi-component integrated design, small-batch customization and rapid production, and cost reduction. The thrust chamber of a liquid rocket engine has the characteristics of a large number of parts, complex assembly and welding, and high production costs for small-batch customization. Fully leveraging the advantages of additive manufacturing technology will help liquid rocket engines achieve the development goals of "high reliability, low cost, and short development cycle". In the additive manufacturing process, laser forming technology is used in conjunction with the layer-by-layer laying of metal powder to finally form the workpiece. However, the existing metal powder laying device has the following problems when used:

[0004] The metal powder spreading device spreads the powder layer by layer through the bottom opening in conjunction with a scraper. However, the existing metal powder spreading device is not convenient for overall uniform spreading. The powder is input into the spreading head through a powder feeding mechanism and a pipeline, and then discharged by the spreading head. In this process, the longitudinal interval of the powder spreading is large. It is difficult to discharge the powder in time within the longitudinal interval by only using the pipeline powder feeding method, and it is easy to form accumulation in the middle, affecting the subsequent flatness. Furthermore, the existing metal powder spreading device is not convenient for breaking up the powder, and some powder has caking and other phenomena. Direct discharge is also one of the factors affecting the uniformity of the powder spreading.

[0005] In response to the above problems, it is urgent to carry out innovative design based on the original one. Summary of the Invention

[0006] The purpose of the present invention is to provide a metal powder spreading device for additive manufacturing of rocket engine thrust chambers, so as to solve the problem that the existing metal powder spreading device proposed in the above background technology is not convenient for overall uniform spreading and is not convenient for breaking up the powder. The technical solution of the present invention addresses the technical problem that the existing technical solution is too single and provides a solution that is significantly different from the existing technology.

[0007] To achieve the above objectives, the present invention provides the following technical solution: a metal powder spreading device for additive manufacturing of a rocket engine thrust chamber, comprising a body, a mounting seat slidably provided on the inner wall of the body cavity via a track, a powder spreading head connected to the bottom of the mounting seat via a cylinder, and a powder spreading chamber provided in the powder spreading head;

[0008] It also includes a powder feeding pipe, which passes through and is fixed on the top of the powder laying head. The powder feeding pipe is connected to the powder feeding mechanism. The top area of ​​the powder laying chamber is connected to a guide mesh plate through a first electric push rod. A sealing plate is fixed to the bottom of the guide mesh plate through a connecting rod. The sealing plate is arranged at the bottom opening of the powder laying chamber. A central rod is installed longitudinally through the connecting rod. Mounting sleeves are fixed on both sides of the central rod through cross rods. A laying aid strip is vertically slidably arranged in the mounting sleeve. A pressing plate is fixed to the bottom of the laying aid strip, and the pressing plate is located on the sealing plate.

[0009] A pushing mechanism is provided in the central rod and on the inner wall of the machine body cavity, and is used for pushing the auxiliary laying strips to move vertically.

[0010] Preferably, the front and rear sides of the guide screen are arranged to be tilted downward in the powder spreading cavity, and the powder spreading cavities are opened at equal intervals laterally in the powder spreading head.

[0011] Preferably, the left and right sides of the sealing plate are inclined upward and outward, the two sides of the sealing plate are in contact with the inner wall of the bottom of the powder spreading chamber, and the bottom of the sealing plate is designed to be a triangular structure.

[0012] Preferably, a plurality of the paving aid strips are provided in the longitudinal position, and the lengths of the plurality of the paving aid strips are adapted to the guide mesh plate.

[0013] Preferably, the auxiliary laying strips and the pressing plate are arranged obliquely in the positive section, and the pressing plate and the top of the sealing plate are parallel to each other.

[0014] Preferably, the pushing mechanism includes a pushing strip, which is installed longitudinally in the powder laying head, the front end of the pushing strip is elastically slidably arranged in the center rod by a spring, and the rear end of the pushing strip is located outside the powder laying head. The pushing strip slides vertically in contact with the powder laying head, and a seal is provided on the pushing strip to prevent powder from overflowing from the powder laying chamber. A pushing head is provided above the rear end of the pushing strip, and the pushing head is fixed on the inner wall of the machine body cavity. A push plate is fixed on the outside of the pushing strip, and the push plate is located in the center rod. A tooth plate is provided on the movable track of the push plate, and the tooth plate is installed through the cross bar and the mounting sleeve. The outer end of the tooth plate is meshed with a tooth roller, and the tooth roller is embedded and rotated in the mounting sleeve through a torsion spring.

[0015] Preferably, the pushing heads are distributed at equal intervals on the inner wall of the cavity of the machine body, the distribution positions of the pushing heads are adapted to the movable tracks of the mounting seat, and the pushing heads are designed to be a hemispherical structure.

[0016] Preferably, the push plate slides within the center rod in a limited position, and the front end of the center rod is designed as an inclined structure to conflict with the tooth plate.

[0017] Preferably, the tooth roller is engaged with the paving aid strip of the rack structure, and the paving aid strip is staggered with the tooth plate.

[0018] Preferably, a scraper is connected to the bottom edge of the mounting seat via a second electric push rod.

[0019] Compared with the prior art, the present invention has the following beneficial effects:

[0020] 1. The present invention provides a plurality of powder spreading chambers with front and rear inclined guide screens to guide the powder falling in the center, and utilizes the gravity of the powder to ensure that the powder can evenly enter the bottom of the guide screen in the longitudinal interval and be discharged through the bottom space of the powder spreading chamber. In this process, the guide screens and sealing plates in the corresponding powder spreading chambers are opened separately, and the other powder spreading chambers are closed, so that powder spreading operations of different metal materials can be performed. On this basis, the corresponding pushing strips are forced to move upward, and during the movement of the powder spreading head, the pushing strips contact the pushing head, and the auxiliary spreading strips can be driven to move upward by the pushing plate, the tooth plate and the tooth roller to contact the guide screen plate, so that the guide screen plate vibrates, which, on the one hand, helps the guide screen plate to guide the powder, and on the other hand, helps to discharge and evenly disperse the internal powder. In this process, the bottom of the powder spreading chamber where powder needs to be spread is opened, and only one set of pushing heads needs to be provided to achieve internal vibration and powder guiding, with a simple and practical structure and high operability.

[0021] 2. In the present invention, a pressure plate is set on the top of the sealing plate, which also utilizes the contact between the pushing strip and the pushing head. The up and down movement of the auxiliary spreading strip drives the pressure plate to move up and down, and cooperates with the inclined structure on the top of the sealing plate. On the one hand, the falling powder is guided, and on the other hand, the powder is intermittently squeezed by the pressure plate, which helps to break up the powder and avoid powder agglomeration. In this process, it cooperates with the vibration of the guide mesh plate to perform vibration and breaking up operations internally, so that the auxiliary spreading strip has multiple effects. On the basis of realizing efficient internal powder spreading, the structure is simplified and it is suitable for diversified powder spreading operations of different metal powders. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic diagram of the front structure of the present invention;

[0023] Figure 2 This is a schematic diagram of the side cross-section structure of the powder spreading head of the present invention;

[0024] Figure 3 This is a schematic diagram of the front cross-section structure of the powder spreading head of the present invention;

[0025] Figure 4 For the present invention Figure 3 A in the middle is an enlarged structural diagram;

[0026] Figure 5 For the present invention Figure 4 The enlarged structural diagram at B in the middle;

[0027] Figure 6 This is a schematic diagram of the push plate structure from a top view according to the present invention;

[0028] Figure 7 For the present invention Figure 4 Enlarged structural diagram at point C in the middle.

[0029] In the figure: 1. Machine body; 2. Mounting seat; 3. Powder spreading head; 4. Powder spreading chamber; 5. Powder feeding pipe; 6. First electric push rod; 7. Guide screen; 8. Connecting rod; 9. Closing plate; 10. Center rod; 11. Cross bar; 12. Mounting sleeve; 13. Auxiliary spreading strip; 14. Pressing plate; 151. Pushing strip; 152. Pushing head; 153. Pushing plate; 154. Tooth plate; 155. Tooth roller; 16. Second electric push rod; 17. Scraper. DETAILED DESCRIPTION

[0030] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0031] See also Figure 1-Figure 7 The present invention provides a technical solution: a metal powder spreading device for additive manufacturing of a rocket engine thrust chamber, wherein a mounting seat 2 is provided on the inner wall of a cavity of a body 1 through a track sliding, a powder spreading head 3 is connected to the bottom of the mounting seat 2 through a cylinder, and a powder spreading cavity 4 is provided in the powder spreading head 3;

[0032] As an embodiment of the present invention, the powder feeding pipe 5 is fixed through the top of the powder laying head 3, the powder feeding pipe 5 is connected to the powder feeding mechanism, the top area of ​​the powder laying chamber 4 is connected to the guide mesh plate 7 through the first electric push rod 6, the bottom of the guide mesh plate 7 is fixed with a sealing plate 9 through a connecting rod 8, the sealing plate 9 is arranged at the bottom opening of the powder laying chamber 4, and a center rod 10 is installed longitudinally through the connecting rod 8. The two sides of the center rod 10 are fixed with mounting sleeves 12 through cross bars 11. A vertical sliding auxiliary laying strip 13 is provided in the mounting sleeve 12, and a pressure plate 14 is fixed to the bottom of the auxiliary laying strip 13. The pressure plate 14 is located on the sealing plate 9;

[0033] As an embodiment of the present invention, the front and rear sides of the guide screen plate 7 are arranged downwardly at an angle in the powder laying chamber 4, and the powder laying chamber 4 is opened at equal intervals in the horizontal direction in the powder laying head 3; the left and right sides of the sealing plate 9 are arranged upwardly at an angle to the outside, and the two sides of the sealing plate 9 are in contact with the inner wall of the bottom of the powder laying chamber 4, and the bottom of the sealing plate 9 is designed to be a triangular structure; a plurality of auxiliary laying strips 13 are arranged in the longitudinal position, and the lengths of the plurality of auxiliary laying strips 13 are adapted to the guide screen plate 7; the auxiliary laying strips 13 and the pressing plate 14 are arranged at an angle in the positive interval, and the pressing plate 14 is parallel to the top of the sealing plate 9; a scraper 17 is connected to the bottom edge of the mounting seat 2 through a second electric push rod 16;

[0034] According to the powder spreading requirements, the corresponding powder spreading chamber 4 is opened, and the first electric push rod 6 drives the guide mesh plate 7 to move upward, so that the guide mesh plate 7 drives the sealing plate 9 to move upward through the connecting rod 8, exposing the opening space at the bottom of the powder spreading chamber 4, and the corresponding metal powder is transported into the powder spreading chamber 4 through the powder feeding mechanism. The powder is guided and dropped by the front and rear inclined guide mesh plate 7, and is discharged through the bottom of the powder spreading chamber 4, so that the powder is evenly spread in the longitudinal position. After the powder spreading is completed, the first electric push rod 6 drives the guide mesh plate 7 to move downward, so that the sealing plate 9 closes the bottom of the powder spreading chamber 4, and the second electric push rod 16 drives the scraper 17 to scrape the powder flat.

[0035] As an embodiment of the present invention, a pushing mechanism is arranged in the center rod 10 and on the inner wall of the cavity of the machine body 1, and the pushing mechanism is used to push the auxiliary laying strip 13 to move vertically; the pushing mechanism includes a pushing strip 151, and the pushing strip 151 is installed longitudinally through the powder laying head 3. The front end of the pushing strip 151 is elastically slidably arranged in the center rod 10 by a spring, and the rear end of the pushing strip 151 is located outside the powder laying head 3. The pushing strip 151 slides vertically in contact with the powder laying head 3. A seal for preventing powder from overflowing from the powder laying cavity 4 is sleeved on the pushing strip 151, and a pushing head 152 is arranged above the rear end of the pushing strip 151. The pushing head 152 is fixed on the inner wall of the cavity of the machine body 1, and a pushing plate 153 is fixed to the outside of the pushing strip 151. The push plate 153 is located inside the center rod 10. A tooth plate 154 is provided on the movable track of the push plate 153. The tooth plate 154 is installed through the cross bar 11 and the mounting sleeve 12. The outer end of the tooth plate 154 is meshed with a tooth roller 155. The tooth roller 155 is embedded and rotated in the mounting sleeve 12 through a torsion spring. The push heads 152 are evenly spaced on the inner wall of the cavity of the body 1. The distribution position of the push heads 152 is adapted to the movable track of the mounting seat 2. The push heads 152 are designed as a hemispherical structure. The push plate 153 slides within the center rod 10. The front end of the center rod 10 is designed as an inclined structure to conflict with the tooth plate 154. The tooth roller 155 meshes with the auxiliary paving strip 13 of the rack structure. The auxiliary paving strip 13 and the tooth plate 154 are staggered.

[0036] The connecting rod 8 drives the pushing strip 151 to move upward through the center rod 10, so that the pushing strip 151 here moves to the position of the pushing head 152. When the powder spreading head 3 moves, the pushing strip 151 moves with it. The pushing strip 151 contacts the pushing head 152, so that the pushing strip 151 is forced to move longitudinally in the center rod 10. The push plate 153 on the pushing strip 151 contacts the tooth plate 154, pushing it to move toward the installation sleeve 12. The tooth plate 154 and the tooth roller 15 5 meshes, driving the toothed roller 155 to rotate, and then the toothed roller 155 meshes with the paving-assisting strip 13, driving the paving-assisting strip 13 to move upward, making it contact with the guide screen 7. The guide screen 7 is forced to vibrate, which helps to guide the powder thereon to fall evenly. At the same time, when the pushing strip 151 separates from the pushing head 152, the pushing strip 151 is reset under the action of the spring, causing the paving-assisting strip 13 to move downward and reset, and the pressing plate 14 contacts the top inclined surface of the sealing plate 9 to squeeze the fallen powder.

[0037] Working principle: According to the powder laying demand, the corresponding powder laying chamber 4 is opened, and the first electric push rod 6 drives the guide screen 7 to move upward, so that the guide screen 7 drives the sealing plate 9 to move upward through the connecting rod 8, exposing the opening space at the bottom of the powder laying chamber 4, and the corresponding metal powder is transported into the powder laying chamber 4 through the powder feeding mechanism. The powder is guided and dropped by the guide screen 7 tilted forward and backward, and is discharged through the bottom of the powder laying chamber 4, so that the powder is evenly laid in the longitudinal position. At the same time, the connecting rod 8 drives the pushing strip 1 through the center rod 10 51 moves upward, so that the pushing bar 151 here moves upward to the position of the pushing head 152, and the pushing bar 151 moves upward in the space through the rear end of the powder spreading head 3, and the connection between the space through the rear end of the powder spreading head 3 and the powder spreading chamber 4 is sealed by the sealing strip on the pushing bar 151 to prevent powder from overflowing. At the same time, the mounting seat 2 and the powder spreading head 3 are driven to move horizontally by the track, and the powder spreading head 3 is driven upward by the cylinder on the mounting seat 2 to separate its bottom from the internal powder layer, and the powder spreading head 3 performs the powder spreading operation during the movement;

[0038] During this process, the pushing strip 151 follows the movement, and the pushing strip 151 contacts the pushing head 152, so that the pushing strip 151 is forced to move longitudinally in the center rod 10, and the push plate 153 on the pushing strip 151 contacts the tooth plate 154, pushing it to move toward the installation sleeve 12, and the tooth plate 154 engages with the tooth roller 155, driving the tooth roller 155 to rotate, and then the tooth roller 155 engages with the auxiliary paving strip 13, driving the auxiliary paving strip 13 to move upward, so that it contacts the guide mesh plate 7, and the guide mesh plate 7 is affected. The force generates vibration, which helps to guide the powder on it to fall evenly. At the same time, when the pushing strip 151 is separated from the pushing head 152, the pushing strip 151 is reset under the action of the spring, so that the auxiliary laying strip 13 moves down and resets, and the pressing plate 14 contacts the top inclined surface of the sealing plate 9 to squeeze the fallen powder to avoid agglomeration. After the powder is spread, the first electric push rod 6 drives the guide screen plate 7 to move downward, so that the sealing plate 9 closes the bottom of the powder spreading chamber 4, and the second electric push rod 16 drives the scraper 17 to scrape the powder flat.

[0039] Any content not described in detail in this specification is prior art known to those skilled in the art. In the description of the present invention, unless otherwise specified, "plurality" means two or more. Terms such as "upper," "lower," "left," "right," "inner," "outer," "front," "rear," "head," and "tail" indicate positions or relationships based on those shown in the accompanying drawings and are intended solely for ease of description and simplification. They do not indicate or imply that the devices or components referred to must have, be constructed, or operate in a specific orientation and are therefore not to be construed as limiting the present invention. Furthermore, terms such as "first," "second," and "third" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. In the description of the present invention, unless otherwise specified or limited, the terms "connected" and "connected" are to be understood broadly, meaning, for example, fixedly connected, detachably connected, or integrally connected; mechanically connected, electrically connected; directly connected, or indirectly connected through an intermediary. Those skilled in the art will understand the specific meanings of these terms in the present invention on a case-by-case basis.

[0040] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A metal powder spreading device for additive manufacturing of a rocket engine thrust chamber, comprising a body (1), a mounting seat (2) being provided on the inner wall of a cavity of the body (1) via a track for sliding, a powder spreading head (3) being connected to the bottom of the mounting seat (2) via a cylinder, and a powder spreading cavity (4) being provided in the powder spreading head (3); Its characteristics are: It also includes a powder feeding pipe (5), the powder feeding pipe (5) is fixed on the top of the powder laying head (3), the powder feeding pipe (5) is connected to the powder feeding mechanism, the top area of ​​the powder laying chamber (4) is connected to a guide screen (7) through a first electric push rod (6), the bottom of the guide screen (7) is fixed with a sealing plate (9) through a connecting rod (8), the sealing plate (9) is arranged at the bottom opening of the powder laying chamber (4), a center rod (10) is longitudinally installed in the connecting rod (8), and mounting sleeves (12) are fixed on both sides of the center rod (10) through cross rods (11), and a vertically sliding auxiliary laying strip (13) is arranged in the mounting sleeve (12), and a pressure plate (14) is fixed to the bottom of the auxiliary laying strip (13), and the pressure plate (14) is located on the sealing plate (9); A pushing mechanism is provided in the center rod (10) and on the inner wall of the cavity of the machine body (1), and is used to push the auxiliary laying strip (13) to move vertically. The pushing mechanism includes a pushing strip (151), and the pushing strip (151) is installed longitudinally through the powder laying head (3). The front end of the pushing strip (151) is elastically slidably provided in the center rod (10) through a spring, and the rear end of the pushing strip (151) is located outside the powder laying head (3). The pushing strip (151) vertically fits and slides at the powder laying head (3). A seal for preventing powder from overflowing from the powder laying cavity (4) is provided on the pushing strip (151), and a pushing head (152) is provided above the rear end of the pushing strip (151). The pushing head (152) The push strip (151) is fixed on the inner wall of the cavity of the machine body (1). A push plate (153) is fixed on the outer side of the push strip (151). The push plate (153) is located in the center rod (10). A tooth plate (154) is provided on the movable track of the push plate (153). The tooth plate (154) is installed through the cross bar (11) and the mounting sleeve (12). The outer end of the tooth plate (154) is engaged with a tooth roller (155). The tooth roller (155) is arranged in the mounting sleeve (12) through the embedded rotation of the torsion spring. A plurality of the auxiliary paving strips (13) are provided in the longitudinal position. The lengths of the plurality of auxiliary paving strips (13) are adapted to the guide mesh plate (7). The auxiliary paving strips (13) move upward to contact the guide mesh plate (7), and the guide mesh plate (7) is subjected to force to generate vibration.

2. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 1, characterized in that: The front and rear sides of the guide screen plate (7) are arranged to tilt downward in the powder spreading cavity (4), and the powder spreading cavity (4) is opened at equal intervals in the horizontal direction in the powder spreading head (3).

3. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 2, characterized in that: The left and right sides of the sealing plate (9) are tilted upwards and outwards, the two sides of the sealing plate (9) are in contact with the inner wall of the bottom of the powder spreading chamber (4), and the bottom of the sealing plate (9) is designed to be a triangular structure.

4. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 3, characterized in that: The auxiliary laying strip (13) and the pressing plate (14) are arranged obliquely in the positive interval, and the pressing plate (14) and the top of the sealing plate (9) are parallel to each other.

5. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 1, characterized in that: The push heads (152) are distributed at equal intervals on the inner wall of the cavity of the body (1); the distribution positions of the push heads (152) are adapted to the movement trajectory of the mounting seat (2); and the push heads (152) are designed as a hemispherical structure.

6. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 5, characterized in that: The push plate (153) slides within the center rod (10) in a limited manner, and the front end of the center rod (10) is designed as an inclined structure to conflict with the tooth plate (154).

7. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 6, characterized in that: The tooth roller (155) is meshed with the auxiliary paving strip (13) of the rack structure, and the auxiliary paving strip (13) and the tooth plate (154) are staggered.

8. The metal powder spreading device for additive manufacturing of a rocket engine thrust chamber according to claim 7, characterized in that: A scraper (17) is connected to the bottom edge of the mounting seat (2) via a second electric push rod (16).

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