Powder spreading device for additive manufacturing

Abstract

The powder spreading device comprises a platform, a mounting frame is arranged above the platform and can move in the length direction of the platform, a feeding roller is rotationally arranged in the mounting frame, a feeding hopper is arranged on the upper portion of the right side of the platform, a discharging port is connected to the lower portion of the feeding roller, and first piezoelectric ceramic blocks are arranged on the inner walls of the two sides of the discharging port correspondingly; two first trigger blocks are arranged on the lower portion of the discharging port, a containing cavity is formed in the feeding roller, a feeding port is connected to the upper portion of the containing cavity, the upper end of the feeding port communicates with the outer wall of the feeding roller, and second piezoelectric ceramic blocks are arranged on the inner walls of the two sides of the feeding port correspondingly. Powder can be quantitatively provided, and the situation that the powder laying thickness is too large is effectively avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and more specifically, to a powder spreading device for additive manufacturing. Background Art

[0002] Metal additive manufacturing is a method of direct forming of metal parts and is the latest development of rapid prototyping technology. It is a technology that uses digital model files as the basis, and uses powdered metal or plastic and other bondable materials to construct objects by printing layer by layer. Additive manufacturing requires powder laying. The existing laying method has a large amount of powder when laying powder, and the amount of powder falling on the processing area will also be correspondingly large, resulting in a thicker laying thickness of powder, which will cause the bonding between layers to be not tight enough, thus affecting the strength and stability of the printed part. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the prior art and provide a powder spreading device for additive manufacturing.

[0004] In order to achieve the above object, the present invention adopts the following technical solution: The invention discloses a powder spreading device for additive manufacturing, comprising a platform, a mounting frame is arranged above the platform, the mounting frame can move along the length direction of the platform, a feeding roller is rotatably arranged in the mounting frame, a feeding hopper is arranged on the upper right part of the platform, a discharging port is connected to the lower part of the feeding hopper, a piezoelectric ceramic block is arranged on the inner walls on both sides of the discharging port, two triggering blocks are arranged on the lower part of the discharging port, an accommodating cavity is opened inside the feeding roller, a feeding port is connected to the upper part of the accommodating cavity, the upper end of the feeding port is communicated with the outer wall of the feeding roller, piezoelectric ceramic blocks are arranged on the inner walls on both sides of the feeding port, a trigger is arranged on the feeding roller, the feeding roller is coaxially connected with a driven gear, a rack is arranged on the platform, the rack is arranged along the length direction of the platform, the driven gear can mesh with the rack, a plurality of triggering blocks matched with the trigger are arranged on the platform, a driving motor is arranged on the platform, the driving motor is driven and connected with a driving gear, the driving gear can mesh with the driven gear, and a scraper assembly is arranged at a position on the right side of the feeding roller in the mounting frame.

[0005] Furthermore, a baffle is provided inside the accommodating chamber, partitions are connected to the left and right sides of the upper part of the baffle, a lifting plate is provided between the partition and the side wall of the accommodating chamber, a spring 1 is connected between the lower part of the lifting plate and the upper part of the baffle, a lifting groove is provided on the feeding roller, a connecting hole is connected to the lower part of the lifting groove, the lower end of the connecting hole is communicated with the accommodating chamber, a connecting rod is connected to the upper part of the lifting plate, the upper end of the connecting rod passes through the connecting hole and extends into the lifting groove, a sleeve is connected to the lower part of the trigger, the upper end of the connecting rod is located in the sleeve, a spring 2 is connected between the bottom of the trigger and the lower part of the lifting groove, a retaining ring is connected to the lower end of the inner wall of the sleeve, a linkage ring is connected to the upper end of the outer periphery of the connecting rod, and the outer diameter of the linkage ring is larger than the inner diameter of the retaining ring.

[0006] Furthermore, a connecting hole 1 is provided on the part of the baffle plate located outside the two partitions, a guide column 1 is connected to a position below the connecting hole 1 at the bottom of the accommodating chamber, a valve block 1 is slidably arranged on the guide column 1, a limiting groove is provided on the outer periphery of the guide column 1, a limiting block is arranged inside the valve block 1, and the limiting block is located in the limiting groove, and a plurality of connecting holes 2 are provided on the part of the baffle plate located between the two partitions, the connecting hole 2 includes a large diameter section, a variable diameter section and a small diameter section arranged in sequence from top to bottom, a fixing rod is connected to the inner wall of the large diameter section, a guide column 2 is connected to the fixing rod, a valve block 2 is slidably arranged on the guide column 2, and a block is connected to the lower end of the guide column 2.

[0007] Furthermore, the mounting frame includes support block 1 and support block 2, a connecting plate is connected between support block 1 and support block 2, a feed roller is rotatably arranged between support block 1 and support block 2, the feed roller is located on the left side of the connecting plate, a screw rod 1 is rotatably arranged on the platform, a drive motor 1 is arranged on the right side of the platform, the drive motor 1 is connected to the screw rod 1 for driving, support block 1 is installed on screw rod 1 through screw rod slider 1, a slide rod is arranged on the platform, and support block 2 is slidably installed on the slide rod.

[0008] Furthermore, a mounting groove is provided at the lower part of the connecting plate, a lifting mechanism is arranged in the mounting groove, and a scraper assembly is installed at the lower part of the lifting mechanism.

[0009] Furthermore, a screw rod 2 is rotatably arranged on the front and rear side walls of the mounting groove, the other end of the screw rod 2 is connected to a driven bevel gear, a driving motor 3 is installed on the connecting plate, the driving motor 3 drives and is connected to an active bevel gear, the active bevel gear is meshed with the driven bevel gear, a screw rod slider 2 is arranged on the screw rod 2, a lifting mechanism is installed at the lower part of each screw rod slider 2, the scraper assembly includes scraper 1 and scraper 2, and scraper 1 and scraper 2 are respectively installed on two lifting mechanisms.

[0010] Furthermore, a material guide block is provided at one end of scraper one and scraper two that are relatively far away, a sliding groove one is opened on the right side of scraper one, a part of scraper two is located in the sliding groove one, a sliding groove two is opened on the left side of scraper two, a part of scraper one is located in the sliding groove two, and a guiding slope is provided at the end of scraper one close to scraper two.

[0011] Furthermore, a material return gap is opened on the left side of the upper part of the platform, a material return plate is arranged in the material return gap, and material guide plates are arranged at both ends of the opening on the right side of the material return gap.

[0012] The beneficial effect of the present invention is that through the cooperation of the feeding hopper and the feeding roller, a fixed amount of powder is received each time for supply, ensuring that there is not too much powder in the working area of ​​the platform, thereby ensuring that the thickness of the laid powder is not too thick. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1A schematic diagram of the structure of a powder spreading device for additive manufacturing in this embodiment; Figure 2 Schematic diagram of the coordination structure of the feeding roller and the feeding hopper in this embodiment; Figure 3 for Figure 2 The enlarged schematic diagram of point A in the middle; Figure 4 for Figure 3 The enlarged schematic diagram of point A in the middle; Figure 5 for Figure 3 The enlarged schematic diagram of point B in the middle; Figure 6 for Figure 3 The enlarged schematic diagram of the center C; Figure 7 is a cross-sectional view of the connecting plate in this embodiment; Figure 8 It is a structural schematic diagram of the scraper assembly in this embodiment.

[0014] Figure numerals: 1, platform; 2, screw rod 1; 3, drive motor 1; 4, support block 1; 5, support block 2; 6, connecting plate; 7, feed roller; 8, return material gap; 9, return material plate; 10, guide plate; 11, driven gear; 12, rack; 13, trigger block 2; 14, drive motor 2; 15, driving gear; 16, drive motor 3; 17, feed hopper; 18, mounting groove; 19, lifting mechanism; 20, scraper assembly; 21, discharge port; 22, piezoelectric ceramic block 1; 23, baffle; 24, connecting hole; 25, accommodating chamber; 26, feed port; 27, piezoelectric ceramic block 2; 28, baffle; 29, partition; 30, vibration motor; 31, lifting plate; 32, spring 1; 33 , connecting rod; 34, trigger block one; 35, lifting groove; 36, trigger; 37, sleeve; 38, retaining ring; 39, linkage ring; 40, spring two; 41, connecting hole one; 42, guide column one; 43, valve block one; 44, limit block; 45, limit groove; 46, support ring; 47, connecting hole two; 48, large diameter section; 49, variable diameter section; 50, small diameter section; 51, fixing rod; 52, guide column two; 53, valve block two; 54, stopper; 55, screw slider two; 56, scraper one; 57, scraper two; 58, screw two; 59, driven bevel gear; 60, active bevel gear; 61, guide block; 62, sliding groove one; 63, sliding groove two; 64, guiding inclined surface; 65, slide rod. DETAILED DESCRIPTION

[0015] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0016] like Figure 1 , Figure 2 As shown, a powder spreading device for additive manufacturing includes a platform 1, a mounting frame is arranged above the platform 1, the mounting frame includes a support block 14 and a support block 25, a connecting plate 6 is connected between the support block 14 and the support block 25, a feed roller 7 is rotatably arranged between the support block 14 and the support block 25, and the feed roller 7 is located on the left side of the connecting plate 6, a screw rod 12 is rotatably arranged on the platform 1, a drive motor 13 is arranged on the right side of the platform 1, and the drive motor 13 is connected to the screw rod 12 by driving, the support block 14 is installed on the screw rod 12 through a screw slider 1, a slide bar 65 is arranged on the platform 1, and the support block 25 is slidably installed on the slide bar 65. The screw rod 12 and the slide bar 65 are both arranged along the length direction of the platform 1, and the slide bar 65 and the screw rod 12 are respectively located at the front side and the rear side of the upper part of the platform 1. The screw rod 12 is driven to rotate by the drive motor 13 to drive the mounting frame to move along the length direction of the platform 1.

[0017] like Figure 2 , Figure 3 As shown, a feeding hopper 17 is arranged at the upper right side of the platform 1, and a discharge port 21 is connected to the lower part of the feeding hopper 17, and piezoelectric ceramic blocks 22 are arranged on the inner walls on both sides of the discharge port 21, and the two piezoelectric ceramic blocks 22 are connected by a wire, and two trigger blocks 34 are arranged at the lower part of the discharge port 21, and a receiving cavity 25 is opened inside the feeding roller 7, and a feeding port 26 is connected to the upper part of the receiving cavity 25, and the upper end of the feeding port 26 is communicated with the outer wall of the feeding roller 7, and piezoelectric ceramic blocks 27 are arranged on the inner walls on both sides of the feeding port 26, and the feeding roller 7 is provided with a trigger 36, the feed roller 7 is coaxially connected with a driven gear 11, the platform 1 is provided with a rack 12, the rack 12 is arranged along the length direction of the platform 1, the driven gear 11 can mesh with the rack 12, the platform 1 is provided with a plurality of trigger blocks 2 13 matched with the trigger 36, the platform 1 is provided with a drive motor 2 14, the drive motor 2 14 is driven and connected with a driving gear 15, the driving gear 15 can mesh with the driven gear 11, and a scraper assembly 20 is provided at the right side of the feed roller 7 in the mounting frame. A power supply is provided in the feed roller 7, and the two levels of the power supply are respectively connected to two piezoelectric ceramic blocks 27.

[0018] When the support block 14 moves to the bottom of the feeding hopper 17, the driven gear 11 can mesh with the driving gear 15. The driving motor 2 14 drives the driving gear 15 to rotate, which drives the driven gear 11 to rotate, thereby driving the feeding roller 7 coaxial with the driven gear 11 to rotate. When the accommodating chamber 25 in the feeding roller 7 is rotated to the top, the two triggers 36 are respectively in contact with the corresponding trigger blocks 1 34, so that the circuit is connected, and the voltage acts on the piezoelectric ceramic block 1 22 and the piezoelectric ceramic block 2 27 respectively, so that the piezoelectric ceramic block 1 22 and the piezoelectric ceramic block 2 27 shrink, and a channel for powder to pass through is formed between the two piezoelectric ceramic blocks 1 22 and the two piezoelectric ceramic blocks 2 27. At the same time, the driving motor 2 14 stops running, so that the feeding roller 7 stops at this position. The powder in the feeding hopper 17 enters the accommodating chamber 25 through the channel. After a certain period of feeding, the driving motor 2 14 drives the driving gear 15 to rotate, so that the feeding roller 7 rotates a certain angle, the trigger 36 and the trigger block 1 34 are disengaged, and then the feeding roller 7 stops. The circuit is disconnected, the piezoelectric ceramic block 1 22 and the piezoelectric ceramic block 2 27 are powered off and restored to their original state, so that the channel is closed and the feeding stops. The driving motor 1 3 drives the screw rod 1 2 to rotate, so as to drive the mounting frame to move, and the driven gear 11 can mesh with the rack 12. During the movement of the mounting frame on the platform 1, the rack 12 can drive the driven gear 11 to rotate, thereby driving the feeding roller 7 to rotate. During the rotation of the feeding roller 7, the trigger 36 can contact the trigger block 2 13 arranged on the platform 1, so that the circuit of the piezoelectric ceramic block 2 27 is connected, the piezoelectric ceramic block 2 27 is powered on and contracted, and the powder in the accommodating chamber 25 can be discharged through the feed port 26 and fall on the processing area of ​​the platform 1. At the same time, the driving motor 1 3 stops running for a period of time, so that the powder can continue to fall for a period of time. The driving motor 1 3 is operated again to drive the mounting frame to move, and the scraper assembly 20 is driven to move during the movement of the mounting frame, and the powder is scraped to the left by the scraper assembly 20, and the powder is driven to move to the left and spread on the processing area while scraping the powder flat. The mounting frame moves to the next trigger block 2 13, and continues to feed, thereby completing the powder laying on the entire processing area.

[0019] Baffles 23 are provided below the inner walls on both sides of the discharge port 21 to block the powder from falling from the gaps between the piezoelectric ceramic blocks 1 22 to the gaps between the piezoelectric ceramic blocks 27 , thereby preventing the powder from falling from the gaps there.

[0020] like Figure 4As shown, a baffle 28 is provided inside the accommodating chamber 25, and partitions 29 are connected to the left and right sides of the upper part of the baffle 28. The two partitions 29 divide the interior of the accommodating chamber 25. The middle area between the two partitions 29 and the outer area between the partition 29 and the side wall of the accommodating chamber 25 are provided with a lifting plate 31 in the outer area. The two ends of the lifting plate 31 are respectively attached to the outer side of the partition 29 and the side wall of the accommodating chamber 25 to prevent the powder from falling from the outer periphery of the lifting plate 31 to the bottom of the lifting plate 31 as much as possible. A spring 32 is connected between the lower part of the lifting plate 31 and the upper part of the baffle 28, a lifting groove 35 is opened on the feeding roller 7, the lower part of the lifting groove 35 is connected with a connecting hole 24, the lower end of the connecting hole 24 is communicated with the accommodating chamber 25, and a sealing ring is provided at the connection between the connecting hole 24 and the accommodating chamber 25, the upper part of the lifting plate 31 is connected with a connecting rod 33, the upper end of the connecting rod 33 passes through the connecting hole 24 and extends into the lifting groove 35, the lower part of the trigger 36 is connected with a sleeve 37, the upper end of the connecting rod 33 is located in the sleeve 37, a spring 2 40 is connected between the bottom of the trigger 36 and the lower part of the lifting groove 35, the lower end of the inner wall of the sleeve 37 is connected with a retaining ring 38, the upper end of the outer periphery of the connecting rod 33 is connected with a linkage ring 39, and the outer diameter of the linkage ring 39 is greater than the inner diameter of the retaining ring 38.

[0021] The falling powder will first fall into the area between the two partitions 29. Due to the obstruction of the partition 29, the powder will be stacked in the middle area. When the height of the stacked powder is higher than the top of the partition 29, the powder in the middle area will fall into the outer area. The powder entering the outer area falls on the lifting plate 31. As the powder entering the outer area increases, the amount of powder on the lifting plate 31 increases, thereby pressing the lifting plate 31 to descend. The lifting plate 31 drives the connecting rod 33 to descend, so that the upper end of the connecting rod 33 descends in the sleeve 37. When the powder on the lifting plate 31 reaches a certain amount, the linkage ring 39 contacts the retaining ring 38 to drive the sleeve 37 to descend, thereby driving the trigger 36 to descend, and the trigger 36 is separated from the trigger block 1 34, so that the circuit is disconnected and the supply of powder is stopped. Through the cooperation of the retaining ring 38 on the sleeve 37 and the linkage ring 39 on the connecting rod 33, it can be avoided that the connecting rod 33 just descends and drives the trigger 36 to move downward, ensuring that a sufficient amount of powder is stored in the accommodating chamber 25.

[0022] Two partitions 29 are provided to block the falling powder, so as to prevent some of the powder on the baffle 28 from falling on the lifting plate 31 when there is less powder, thereby preventing the lifting plate 31 from driving the trigger 36 to descend when not enough powder is collected in the accommodating chamber 25.

[0023] like Figure 5 , Figure 6As shown, the side of the baffle 28 away from the partition 29 is a structure with a low middle and high sides, and a slope structure for feeding toward the middle at both ends of the lower part of the baffle 28. A connecting hole 41 is provided on the part of the baffle 28 located outside the two partitions 29, and a guide column 42 is connected to the position below the connecting hole 41 at the bottom of the accommodating chamber 25. The guide column 42 is vertically arranged, and a valve block 43 is slidably arranged on the guide column 42. A limiting groove 45 is provided on the outer periphery of the guide column 42, and a limiting block 44 is arranged inside the valve block 43. The limiting block 44 is located in the limiting groove 45. A support ring 46 is connected to the outer periphery of the guide column 42 below the valve block 43. When the feed roller 7 rotates so that the accommodating chamber 25 is located at the upper side, the valve block 43 can be separated from the connecting hole 41. When the feed roller 7 rotates so that the accommodating chamber 25 is located at the lower side, the valve block 43 is at least partially located in the connecting hole 41 to block the connecting hole 41. The baffle plate 28 is provided with a plurality of second communication holes 47 in the portion between the two partition plates 29. The second communication hole 47 includes a large diameter section 48, a reduced diameter section 49 and a small diameter section 50 arranged in sequence from top to bottom. The diameter of the large diameter section 48 is larger than the diameter of the small diameter section 50. The diameter of the reduced diameter section 49 decreases uniformly from top to bottom. A fixing rod 51 is connected to the inner wall of the large diameter section 48. A guide column 52 is connected to the fixing rod 51. A guide column 52 is slidably provided on the guide column 52. The valve block 2 53 and the lower end of the guide column 2 52 are connected with a stopper 54. When the feed roller 7 rotates so that the accommodating chamber 25 is located at the top, the valve block 2 53 abuts against the stopper 54 under the action of gravity, and at the same time, the outer periphery of the valve block 2 53 fits with the outer periphery of the reducing section 49. When the feed roller 7 rotates so that the accommodating chamber 25 is located at the bottom, the valve block 2 53 abuts against the fixed rod 51 under the action of gravity, and a gap is left between the outer periphery of the valve block 2 53 and the inner wall of the reducing section 49.

[0024] When the powder enters the area between the partition 29 and the side wall of the accommodating chamber 25, some of the powder may fall into the area between the lifting plate 31 and the baffle 28. A connecting hole 41 is provided. Since the valve block 43 is located below the connecting hole 41 under the action of gravity when the accommodating chamber 25 is at the top, this part of the powder can enter the area below the baffle 28 through the connecting hole 41. After the feeding roller 7 rotates, when the accommodating chamber 25 reaches the bottom and starts to supply powder to the top of the platform 1, the valve block 43 enters the connecting hole 41 under the action of gravity to close the connecting hole 41. The powder located between the baffle 28 and the bottom of the accommodating chamber 25 falls toward the middle along the inclined baffle 28. At this time, the valve block 2 53 moves toward the large diameter section 48 under the action of gravity, so that there is a gap between the outer periphery of the valve block 2 53 and the inner wall of the variable diameter section 49. The powder falling along the baffle 28 can enter the connecting hole 2 47, and then return to the accommodating chamber 25, ensuring that the powder will not be left behind.

[0025] A vibration motor 30 is installed on the baffle 28, and the vibration motor 30 drives the baffle 28 to vibrate, so as to shake off the powder adhering to the baffle 28, thereby avoiding the residual powder in the accommodating chamber 25, so as to ensure that all the powder is supplied each time.

[0026] like Figure 1 As shown, a feed-returning notch 8 is provided on the left side of the upper part of the platform 1, the width of the right side of the feed-returning notch 8 is greater than the width of the left side, a feed-returning plate 9 is provided in the feed-returning notch 8, the right end of the feed-returning plate 9 is flush with the upper surface of the platform 1, the height of the left end of the feed-returning plate 9 is lower than the height of the right end, and guide plates 10 are provided at both ends of the right opening of the feed-returning notch 8. Excess powder on the platform 1 can be scraped into the feed-returning notch 8 by the scraper assembly 20, and the powder falls along the feed-returning plate 9 and is collected.

[0027] like Figure 7 , Figure 8 As shown, a mounting groove 18 is provided at the lower portion of the connecting plate 6, and screw rod 2 58 is rotatably provided on the front and rear side walls of the mounting groove 18, and the other end of screw rod 2 58 is connected to a driven bevel gear 59, a driving motor 3 16 is installed on the connecting plate 6, and the driving motor 3 16 is driven and connected to an active bevel gear 60, and the active bevel gear 60 is located in the mounting groove 18 and meshes with the driven bevel gears 59 on both sides, a screw rod slider 2 55 is provided on the screw rod 2 58, and a lifting mechanism 19 is installed at the lower portion of each screw rod slider 2 55, and the scraper assembly 20 includes a scraper 1 56 and a scraper 2 57, and the scraper 1 56 and the scraper 2 57 are respectively installed on two lifting mechanisms 19. A sliding groove 1 62 is provided on the right side of the scraper 1 56, and the end of the scraper 2 57 close to the scraper 1 56 is located in the sliding groove 1 62. A sliding groove 2 63 is provided on the left side of the scraper 2 57, and the end of the scraper 1 56 close to the scraper 2 57 is located in the sliding groove 2 63. A guiding slope 64 is provided on the end of the scraper 1 56 close to the scraper 2 57. The lifting mechanism 19 is a cylinder or a hydraulic cylinder. The lifting mechanism 19 controls the lifting and lowering of the scraper assembly 20, thereby adjusting the height of the scraper assembly 20 to control the thickness of the powder. A guide block 61 is provided at the end of the scraper 1 56 and the scraper 2 57 that is relatively far away. The guide block 61 is located on the side close to the feeding roller 7. The powder on both sides can be gathered inward through the guide block 61 to prevent the powder from escaping from both sides of the scraper 1 56 and the scraper 2 57, ensuring that the powder remains in the working area.

[0028] The driving motor three 16 drives the active bevel gear 60 to rotate, and the active bevel gear 60 drives the driven bevel gears 59 on both sides to rotate, and the driven bevel gear 59 drives the screw rod 2 58 to rotate to drive the lifting mechanism 19 to move, so that the scraper 1 56 and the scraper 2 57 move relative to each other, and the overall length is reduced, so that when approaching the return material gap 8, the powder can be gathered into the opening range of the return material gap 8, so that all the powder can enter the return material gap 8 and be collected.

[0029] When the scraper 1 56 and the scraper 2 57 move relative to each other, the guiding slope 64 can squeeze out the powder located at the sliding groove 2 63 to prevent the powder from being stuck between the scraper 1 56 and the scraper 2 57 .

[0030] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A powder spreading device for additive manufacturing, characterized in that: The invention comprises a platform (1), a mounting frame is arranged above the platform (1), the mounting frame can move along the length direction of the platform (1), a feeding roller (7) is rotatably arranged inside the mounting frame, a feeding hopper (17) is arranged at the upper right part of the platform (1), the lower part of the feeding hopper (17) is connected to a discharge port (21), the inner walls on both sides of the discharge port (21) are provided with piezoelectric ceramic blocks (22), the lower part of the discharge port (21) is provided with two trigger blocks (34), a accommodating cavity (25) is provided inside the feeding roller (7), the upper part of the accommodating cavity (25) is connected to a feeding port (26), the upper end of the feeding port (26) is connected to the outer wall of the feeding roller (7), and the inner walls on both sides of the feeding port (26) are provided with piezoelectric ceramic blocks (22). The invention relates to an electric ceramic block 2 (27), a trigger (36) is arranged on the feed roller (7), the feed roller (7) is coaxially connected with a driven gear (11), a rack (12) is arranged on the platform (1), the rack (12) is arranged along the length direction of the platform (1), the driven gear (11) can mesh with the rack (12), a plurality of trigger blocks 2 (13) matched with the trigger (36) are arranged on the platform (1), a drive motor 2 (14) is arranged on the platform (1), the drive motor 2 (14) is drivingly connected with a driving gear (15), the driving gear (15) can mesh with the driven gear (11), and a scraper assembly (20) is arranged at a position on the right side of the feed roller (7) in the mounting frame.

2. The powder spreading device for additive manufacturing according to claim 1, characterized in that: A baffle (28) is provided inside the accommodating chamber (25), and partitions (29) are connected to the left and right sides of the upper part of the baffle (28), and a lifting plate (31) is provided between the partition (29) and the side wall of the accommodating chamber (25), and a spring (32) is connected between the lower part of the lifting plate (31) and the upper part of the baffle (28), and a lifting groove (35) is provided on the feeding roller (7), and the lower part of the lifting groove (35) is connected to a connecting hole (24), and the lower end of the connecting hole (24) is connected to the accommodating chamber (25), and the upper part of the lifting plate (31) is connected to the connecting hole (24). A connecting rod (33) is provided, the upper end of the connecting rod (33) passes through a connecting hole (24) and extends into a lifting groove (35), the lower part of the trigger (36) is connected to a sleeve (37), the upper end of the connecting rod (33) is located in the sleeve (37), a spring (40) is connected between the bottom of the trigger (36) and the lower part of the lifting groove (35), the lower end of the inner wall of the sleeve (37) is connected to a retaining ring (38), the upper end of the outer periphery of the connecting rod (33) is connected to a linkage ring (39), and the outer diameter of the linkage ring (39) is greater than the inner diameter of the retaining ring (38).

3. The powder spreading device for additive manufacturing according to claim 2, characterized in that: A communicating hole (41) is provided on the baffle plate (28) at a portion located outside the two partition plates (29); a guide column (42) is connected to a position located below the communicating hole (41) at the bottom of the accommodating chamber (25); a valve block (43) is slidably provided on the guide column (42); a limiting groove (45) is provided on the outer periphery of the guide column (42); a limiting block (44) is provided inside the valve block (43); the limiting block (44) is located in the limiting groove (45); the baffle plate (28) is provided with a plurality of guide columns (43); and the limiting block (44) is provided in the limiting groove (45). 8) is provided with a plurality of second communicating holes (47) in the portion between the two partitions (29), the second communicating holes (47) comprising a large diameter section (48), a reduced diameter section (49) and a small diameter section (50) arranged in sequence from top to bottom, a fixing rod (51) is connected to the inner wall of the large diameter section (48), the fixing rod (51) is connected to a second guiding column (52), a valve block (53) is slidably arranged on the second guiding column (52), and a stopper (54) is connected to the lower end of the second guiding column (52).

4. The powder spreading device for additive manufacturing according to claim 1, characterized in that: The mounting frame comprises a support block 1 (4) and a support block 2 (5), a connecting plate (6) being connected between the support block 1 (4) and the support block 2 (5), the feeding roller (7) being rotatably arranged between the support block 1 (4) and the support block 2 (5), the feeding roller (7) being located on the left side of the connecting plate (6), a screw rod 1 (2) being rotatably arranged on the platform (1), a driving motor 1 (3) being arranged on the right side of the platform (1), the driving motor 1 (3) being drivingly connected to the screw rod 1 (2), the support block 1 (4) being installed on the screw rod 1 (2) via a screw rod slider 1, a sliding rod (65) being arranged on the platform (1), and the support block 2 (5) being slidably installed on the sliding rod (65).

5. The powder spreading device for additive manufacturing according to claim 4, characterized in that: The lower part of the connecting plate (6) is provided with a mounting groove (18), a lifting mechanism (19) is arranged in the mounting groove (18), and a scraper assembly (20) is installed at the lower part of the lifting mechanism (19).

6. The powder spreading device for additive manufacturing according to claim 5, characterized in that: A screw rod 2 (58) is rotatably arranged on the front and rear side walls of the installation groove (18), and the other end of the screw rod 2 (58) is connected to a driven bevel gear (59). A driving motor 3 (16) is installed on the connecting plate (6), and the driving motor 3 (16) is driven and connected to an active bevel gear (60), and the active bevel gear (60) is meshed with the driven bevel gear (59). A screw rod slider 2 (55) is arranged on the screw rod 2 (58), and a lifting mechanism (19) is installed at the lower part of each screw rod slider 2 (55). The scraper assembly (20) includes a scraper 1 (56) and a scraper 2 (57), and the scraper 1 (56) and the scraper 2 (57) are respectively installed on two lifting mechanisms (19).

7. The powder spreading device for additive manufacturing according to claim 6, characterized in that: A material guide block (61) is provided at one end of the scraper plate 1 (56) and the scraper plate 2 (57) which are relatively far away from each other; a sliding groove 1 (62) is provided on the right side of the scraper plate 1 (56), and a part of the scraper plate 2 (57) is located in the sliding groove 1 (62); a sliding groove 2 (63) is provided on the left side of the scraper plate 2 (57), and a part of the scraper plate 1 (56) is located in the sliding groove 2 (63); and a guiding inclined surface (64) is provided at one end of the scraper plate 1 (56) close to the scraper plate 2 (57).

8. The powder spreading device for additive manufacturing according to claim 1, characterized in that: A material return notch (8) is provided on the left side of the upper part of the platform (1), a material return plate (9) is arranged in the material return notch (8), and material guide plates (10) are arranged at both ends of the right opening of the material return notch (8).

Images