Powder spreading device and additive manufacturing equipment

Abstract

The invention belongs to the technical field of additive manufacturing, and discloses a powder spreading device and additive manufacturing equipment. The powder spreading device comprises a linear rail, a sliding part, a driving mechanism and a telescopic pipe, wherein the linear rail extends in the first direction; the sliding part is provided with a sliding cavity extending in the first direction, an enclosure bulkhead forming the sliding cavity is slidably connected to the linear rail, the sliding part is fixedly connected with a powder laying assembly, the two ends, in the first direction, of the sliding part are each provided with a first sealing part, and the first sealing parts are used for sealing gaps between the enclosure bulkhead and the linear rail; one end of the telescopic pipe is hermetically connected to the first sealing piece, the other end is correspondingly hermetically connected to the linear rail, and the length of the telescopic pipe in the first direction is adjustable; the output end of the driving mechanism is connected with a sliding piece or a powder laying assembly. According to the powder spreading device, high-temperature isolation and dust isolation can be achieved on the sliding part, the lubricating performance of the sliding part is improved, the service life of the powder spreading device is prolonged, the use reliability of the powder spreading device is improved, and the maintenance cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of additive manufacturing, and in particular to a powder spreading device and additive manufacturing equipment. Background Art

[0002] Electron beam powder-spreading additive manufacturing equipment, also known as electron beam 3D printing equipment, is characterized by using electron beams to selectively melt metal powder particles in a specific area on the powder bed, thereby realizing the printing and manufacturing of metal three-dimensional entities. Electron beam powder-spreading additive manufacturing technology has great development prospects due to its advantages such as high output power and scanning speed, and good preheating effect, among which the powder-spreading effect of metal powder plays an important role.

[0003] In the prior art, powder spreading is usually achieved by moving the powder spreading assembly driven by chains and sprockets, and the moving trajectory of the powder spreading and feeding assembly is positioned by a double linear bearing group in conjunction with an optical axis. The powder spreading and scraping structure using this structure is relatively common, but this structure has the following disadvantages:

[0004] 1. The clearance between the optical axis and the bearing is usually small, and it is difficult to achieve a good seal between the optical axis and the bearing. Therefore, powder can easily enter the ball and raceway of the linear bearing from the installation clearance hole and the outer surface of the optical axis, causing the bearing to fail and get stuck. Although high-temperature resistant seals are used as protection in this structure, the ball may still be stuck by powder in actual use.

[0005] 2. Part of the optical axis will be exposed to the molding area of ​​the printing equipment. Local areas of the optical axis will be affected by high temperature, and the bearings usually pass through the molding powder bed area periodically. This causes the fit clearance between the optical axis and the bearing to change. The powder laying quality is difficult to control during the use of the equipment, and the bearings are easily damaged when used in this environment.

[0006] 3. The existing structure usually adopts the heat insulation method of blocking with an external heat insulation board. Although this can block most of the heat, the heat insulation board will store heat for a long time during long-term printing of the equipment, and the heat radiation will have a greater impact on the optical axis and bearings.

[0007] 4. In electron beam 3D printing equipment, dust or powder blowing can easily cause powder to enter the bearing. In order to prevent dust, dust-proof structures need to be made at both ends of the bearing or the main dust-proof structures include lip seals and glass fiber packing protection. Although the overall protection effect of the lip seal is better than that of the packing seal rope, the temperature resistance of the lip seal (≤250℃) is lower than that of the glass fiber packing (≥400℃). Therefore, in the field of 3D printing, glass fiber packing is often used as a dust-proof seal. Because the effect of packing rope protection is related to the material used, the installation method and the tightness of the installation, its actual dust-proof effect is poor during use, the bearing service life is short, and the maintenance frequency is high. And after the dust affects the lubrication of the bearing, the use time of the bearing is significantly reduced.

[0008] In summary, the main problems of the existing powder spreading device are the sliding components that drive the powder spreading components to move. The sliding components need to solve the following three problems:

[0009] 1. Lubrication problem: In electron beam printing equipment, there cannot be oil vapor in the filament use environment. The presence of oil vapor will seriously affect the life and operation status of the electron beam, and the electron gun will have a series of problems such as bias voltage drop, resulting in printing failure.

[0010] 2. Dust prevention problem: Powder-spreading additive equipment cannot avoid dust, and the dust will enter the matching gap between the bearing and the shaft. The presence of grease will adhere the dust to the bearing balls, bearing grooves and optical axis, causing the balls in the bearings to be unable to rotate. In severe cases, it will cause damage to the bearings, thereby affecting the movement stability of the powder-spreading components.

[0011] 3. High temperature problem: During the reciprocating motion of the powder spreading mechanism, the linear bearing needs to pass through the high-temperature powder bed area periodically. The long-term accumulation of heat causes the bearing temperature to rise. The high temperature factor is also one of the important factors that cause the bearing to jam.

[0012] Therefore, there is an urgent need to provide a new type of powder spreading device and additive manufacturing equipment to solve the above-mentioned technical problems in the prior art. Summary of the invention

[0013] One object of the present invention is to provide a powder spreading device that can achieve high temperature isolation and dust isolation for sliding parts, improve the lubrication performance of the sliding parts, thereby increasing the service life and reliability of the powder spreading device and reducing maintenance costs.

[0014] To achieve this object, the present invention adopts the following technical solutions:

[0015] The powder spreading device includes a linear track, a sliding member, a driving mechanism and a telescopic tube, wherein the linear track is extended along a first direction; the sliding member has a sliding cavity extending along the first direction, the surrounding wall forming the sliding cavity is slidably connected to the linear track, the sliding member is fixed with a powder spreading assembly, both ends of the sliding member along the first direction are provided with a first sealing member, the first sealing member is used to seal the gap between the surrounding wall and the linear track; both ends of the sliding member along the first direction are provided with the telescopic tube, one end of the telescopic tube is sealedly connected to the first sealing member, and the other end is correspondingly sealedly connected to the linear track, and the length of the telescopic tube along the first direction is adjustable; the output end of the driving mechanism is connected to the sliding member or the powder spreading assembly.

[0016] Optionally, the powder spreading device further includes a vacuum box, and both ends of the linear track along the first direction are fixedly connected to the inner wall of the vacuum box, and both ends of the linear track along the first direction are provided with a second seal, one end of the second seal is fixed to the inner wall of the vacuum box, and the other end is sealedly connected to the telescopic tube.

[0017] Optionally, there is a hollow inner cavity between the circumferential outer wall of the above-mentioned linear track and the circumferential inner wall of the above-mentioned telescopic tube, and the two above-mentioned hollow inner cavities are correspondingly connected to two air circuit connecting pipes arranged on the outer wall of the above-mentioned vacuum box, and the above-mentioned driving mechanism includes an air compression device, and the above-mentioned air circuit connecting pipe is selectively connected to the above-mentioned air compression device.

[0018] Optionally, the sliding member is provided with a connecting bracket, and the powder spreading assembly is fixedly connected to the connecting bracket.

[0019] Optionally, the driving mechanism includes a driving member fixedly mounted on the inner wall of the vacuum box, a driving chain is provided at the output end of the driving member, and the driving chain is also wound around a sprocket provided on the inner wall of the vacuum box, so that at least part of the driving chain extends along the first direction and forms a horizontal part, and the connecting bracket is fixedly connected to the horizontal part.

[0020] Optionally, the linear rails are arranged in plurality along the second direction at intervals, each of the linear rails is correspondingly provided with the sliding member, the plurality of sliding members are fixedly connected to the connecting bracket, and the second direction is perpendicular to the first direction.

[0021] Optionally, a screw portion is formed on the outer wall of at least one of the linear rails, the screw portion is connected with a screw nut, the connecting bracket is fixed with the screw nut, and a driving member is provided on the outer wall of the vacuum box for driving the screw portion to rotate.

[0022] Optionally, the linear track includes an optical axis, and the sliding member is a linear bearing; or, the linear track is a slide rail, and the sliding member is a slider.

[0023] Optionally, the maximum elongation of the telescopic tube is not less than 20%, and the maximum compression rate of the telescopic tube is not less than 55%.

[0024] Another object of the present invention is to provide an additive manufacturing device, which includes a powder spreading device as described in any of the above schemes. The additive manufacturing device can improve the lubrication performance of the sliding parts, reduce the occurrence of jamming, improve the printing performance of the additive manufacturing device, and increase the service life and reliability of the powder spreading device, thereby reducing the maintenance cost of the additive manufacturing device.

[0025] Beneficial effects:

[0026] The powder spreading device in the present invention realizes the guiding and sliding limiting function of the sliding part through the linear track, ensures the smooth movement of the sliding part, thereby driving the powder spreading component to move along the first direction to complete the powder spreading operation. In this process, the two ends of the sliding cavity of the sliding part are sealed by the first sealing part to prevent dust from entering the gap between the sliding cavity and the linear track. At the same time, the linear track is covered with a telescopic tube, which will be telescopic with the movement of the sliding part, and further seals and protects the first sealing part and the linear track to prevent dust from falling on the surface of the linear track, thereby preventing the sliding part from being stuck by the dust on the linear track, ensuring the sliding performance of the sliding part on the linear track, improving the lubrication performance, and preventing the high temperature environment from causing damage to the first sealing part, thereby improving the high temperature resistance of the powder spreading device; finally, it can also prevent the evaporation of lubricating oil caused by high temperature, and prevent the lubricating oil vapor from affecting the forming effect of the electron beam. The powder spreading device can achieve high temperature isolation and dust isolation for the sliding part, improve the lubrication performance of the sliding part, thereby improving the service life and reliability of the powder spreading device, and reducing the maintenance cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic front view of the powder spreading device in Example 1 provided in a specific embodiment of the present invention;

[0028] Figure 2 It is an axonometric schematic diagram of a powder spreading device in Example 2 provided in a specific embodiment of the present invention;

[0029] Figure 3 It is a schematic front view of a powder spreading device in Example 2 provided in a specific embodiment of the present invention;

[0030] Figure 4 It is a schematic front view of the powder spreading device in Example 3 provided in the specific implementation mode of the present invention.

[0031] In the figure:

[0032] 100, linear rail; 110, screw part; 200, sliding part; 300, telescopic tube; 310, first sealing part; 320, second sealing part; 400, powder spreading assembly; 410, connecting bracket; 500, vacuum box; 510, air path connecting pipe; 610, driving part; 620, reducer; 630, coupling; 640, sprocket; 650, driving chain; 651, horizontal part. DETAILED DESCRIPTION

[0033] The present invention will be further described in detail below in conjunction with the accompanying drawings and embodiments. It is to be understood that the specific embodiments described herein are only used to explain the present invention, rather than to limit the present invention. It should also be noted that, for ease of description, only parts related to the present invention, rather than all structures, are shown in the accompanying drawings.

[0034] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connected", "connected", and "fixed" 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 an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] In the present invention, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0036] In the description of this embodiment, the terms "upper", "lower", "right", etc., directions or positional relationships are based on the directions or positional relationships shown in the drawings, and are only for the convenience of description and simplification of operation, 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 limiting the present invention. In addition, the terms "first" and "second" are only used to distinguish in the description and have no special meaning.

[0037] In the prior art, during the powder spreading process, metal powder needs to be scraped off by a powder spreading structure. The scraping structure often uses a linear bearing in conjunction with a linear guide rail to achieve horizontal translation. The sliding component constrains the movement trajectory of the powder spreading module through the cooperation of the guide rail and the bearing or slider. The cooperation between the moving component and the guide rail requires high precision, smooth sliding and low resistance. However, in actual use, because the cooperation between the ball and the guide rail of the sliding component is greatly affected by high temperature and dust, there will be jamming between the ball and the guide rail, and the sliding resistance will increase, which will lead to abnormal scraping of the powder. In addition, it is also necessary to solve the lubrication, dust prevention and high temperature resistance problems of linear bearings in a vacuum environment.

[0038] The following is combined with Figure 1 To Attachment Figure 4 , as well as Examples 1 to 3, describe in detail the powder spreading device in this specific embodiment, and how the powder spreading device in this specific embodiment can achieve high temperature isolation and dust isolation for the sliding part 200, thereby improving the lubrication performance of the sliding part 200.

[0039] The first direction described in this specific implementation manner is Figure 1 , Figure 3 and Figure 4 The X direction shown is the horizontal direction, and the second direction is Figure 3 and Figure 4 The Y direction shown in , that is, the vertical direction, and the X direction is perpendicular to the Y direction.

[0040] Embodiment 1

[0041] Please refer to Figure 1 The powder spreading device in this embodiment includes a linear track 100, a sliding member 200, a driving mechanism and a telescopic tube 300. The linear track 100 is extended along a first direction; the sliding member 200 has a sliding cavity extending along the first direction, and the surrounding wall forming the sliding cavity is slidably connected to the linear track 100. The sliding member 200 is fixedly connected with a powder spreading assembly 400. Both ends of the sliding member 200 along the first direction are provided with a first sealing member 310, and the first sealing member 310 is used to seal the gap between the surrounding wall and the linear track 100; both ends of the sliding member 200 along the first direction are provided with the telescopic tube 300, one end of the telescopic tube 300 is sealedly connected to the first sealing member 310, and the other end is correspondingly sealedly connected to the linear track 100, and the length of the telescopic tube 300 along the first direction is adjustable; the output end of the driving mechanism is connected with the sliding member 200 or the powder spreading assembly 400.

[0042] The powder spreading device in this embodiment realizes the guiding and sliding limiting effect on the sliding member 200 through the linear track 100, ensuring the smooth movement of the sliding member 200, thereby driving the powder spreading assembly 400 to move along the first direction to complete the powder spreading operation. During this process, both ends of the sliding cavity of the sliding member 200 are sealed by the first sealing member 310 to prevent dust from entering the gap between the sliding cavity and the linear track 100. At the same time, the linear track 100 is covered with a telescopic tube 300, which will be retracted and expanded with the movement of the sliding member 200, and further seals and protects the first sealing member 310 and the linear track 100 to prevent dust from falling on the surface of the linear track 100, thereby preventing the sliding member 200 from being stuck by the dust on the linear track 100, ensuring the sliding performance of the sliding member 200 on the linear track 100, improving the lubrication performance, and preventing the high temperature environment from damaging the first sealing member 310, thereby improving the high temperature resistance of the powder spreading device; finally, it can also prevent the evaporation of lubricating oil caused by high temperature, and prevent the lubricating oil vapor from affecting the forming effect of the electron beam. The powder spreading device can achieve high temperature isolation and dust isolation for the sliding part 200, and improve the lubrication performance of the sliding part 200, thereby increasing the service life and reliability of the powder spreading device and reducing maintenance costs.

[0043] In this embodiment, two telescopic tubes 300 are provided, and the two telescopic tubes 300 are correspondingly provided at both ends of the above-mentioned sliding member 200. Each telescopic tube 300 can be integrally formed, or can be formed by welding, bonding, hot-melt connection, flange connection, etc., connecting and fixing multiple sections of telescopic tubes 300 end to end, which will not be described in detail here.

[0044] Optionally, the linear track 100 includes an optical axis, and the sliding member 200 is a linear bearing; or, the linear track 100 is a slide rail, and the sliding member 200 is a slider. As long as the linear track 100 can limit and guide the sliding member 200 in the first direction, the specific structures of the linear track 100 and the sliding member 200 are not specifically limited in this embodiment.

[0045] Specifically, the linear rail 100 in this embodiment is a cylindrical optical axis, and the sliding member 200 is a linear bearing. The linear bearing is a linear motion system with high precision, low cost and low friction resistance. The linear bearing is used in combination with a guide shaft, and utilizes the rolling motion of a ball to achieve an infinite linear motion direct motion system.

[0046] As a preferred embodiment, the maximum elongation of the telescopic tube 300 is not less than 20%, and the maximum compression of the telescopic tube 300 is not less than 55%. That is, the total length of the telescopic tube 300 after elongation is 1.2 times or more of the original length, and the total length of the telescopic tube 300 after compression is 0.45 times or less of the original length. The greater the maximum elongation of the telescopic tube 300, the better, and the greater the maximum compression, the better, so that the original length of the telescopic tube 300 can be made smaller, so that the elongation and compression of the telescopic tube 300 can be achieved at a lower cost, thereby reducing the production cost.

[0047] The material of the telescopic tube 300 can be a high temperature resistant synthetic material, such as ceramic, etc., or a metal material such as stainless steel, aluminum profile, or a high temperature resistant resin or rubber, which will not be described in detail here. In this embodiment, the telescopic tube 300 is a stainless steel bellows, which can not only withstand high temperatures, but also has a low manufacturing cost.

[0048] Please continue to refer to Figure 1 Optionally, the powder spreading device further comprises a vacuum box 500, both ends of the linear track 100 along the first direction are fixed to the inner wall of the vacuum box 500, and both ends of the linear track 100 along the first direction are provided with a second sealing member 320, one end of the second sealing member 320 is fixed to the inner wall of the vacuum box 500, and the other end is sealedly connected to the telescopic tube 300. The second sealing member 320 is used to seal the section where the telescopic tube 300 is connected to the inner wall of the vacuum box 500, so as to ensure the sealing performance between the telescopic tube 300 and the linear track 100, prevent dust from entering the surface of the linear track 100 from the end of the telescopic tube 300, and further improve the dust isolation effect of the powder spreading device.

[0049] In this embodiment, both the first sealing member 310 and the second sealing member 320 can be selected as sealing flanges. When the second sealing member 320 is connected to the telescopic tube 300, welding can be used for sealing to ensure sealing performance, which will not be described in detail here.

[0050] The driving mechanism in the first embodiment is described in detail below. In this embodiment, a hollow inner cavity is provided between the circumferential outer wall of the linear track 100 and the circumferential inner wall of the telescopic tube 300. The two hollow inner cavities are correspondingly connected to the two air path connecting pipes 510 provided on the outer wall of the vacuum box 500. The driving mechanism includes an air compression device, and the air path connecting pipes 510 are selectively connected to the air compression device (not shown in the figure). Since a hollow cavity is formed between the telescopic tube 300, the first seal 310, the second seal 320 and the linear track 100, the hollow cavity is closed. By injecting compressed gas into one of the hollow cavities through an air compression device, the pressure of the hollow cavity can be increased and greater than that of the other hollow cavity. While achieving a pressure difference, the sliding member 200 and the powder spreading assembly 400 are driven to move. The driving mechanism is driven by compressed gas, and has a simple control structure and low cost. The alternating drive of compressed air can take away part of the heat on the sliding member 200 and the linear track 100, and the lubrication properties of the sliding member 200 can be completely retained. Compared with the original structure, the service life of the sliding member 200 can be increased, but the control accuracy is relatively poor.

[0051] In this embodiment, when compressed gas is injected into one of the hollow cavities, the other hollow cavity can be sucked under negative pressure, or the other hollow cavity can be directly connected to the atmosphere to ensure that the sliding member 200 can move smoothly when compressed gas is injected. When the linear track 100 and the sliding member 200 are provided with multiple corresponding ones, the gas path connecting pipe 510 can be provided with multiple branch pipes to connect the corresponding hollow cavities, which will not be repeated here.

[0052] Preferably, the sliding member 200 is provided with a connecting bracket 410, and the powder spreading assembly 400 is fixedly connected to the connecting bracket 410. The setting of the connecting bracket 410 can realize the connection between the sliding member 200 and the powder spreading assembly 400, thereby realizing the synchronous movement of the sliding member 200 and the powder spreading assembly 400. In this embodiment, the sliding member 200 is sandwiched between the connecting bracket 410 and the linear track 100, and the sliding member 200 includes a plurality of linear bearings, specifically 2, 3, 4, 5 or 6, so as to further improve the sliding stability of the powder spreading assembly 400 on the linear track 100, which will not be repeated here.

[0053] Embodiment 2

[0054] In this embodiment, the difference from the above-mentioned embodiment 1 is only the difference in the driving mechanism. The driving mechanism in this embodiment 2 includes a driving member 610 fixedly mounted on the inner wall of the vacuum box 500. The output end of the driving member 610 is provided with a driving chain 650. The driving chain 650 is also wound around a sprocket 640 provided on the inner wall of the vacuum box 500, so that at least part of the driving chain 650 is extended along the first direction and formed into a horizontal portion 651. The connecting bracket 410 is fixedly connected to the horizontal portion 651. Through the combination of the sprocket 640, the driving member 610 and the driving chain 650, the driving chain 650 can be driven to perform a cyclic reciprocating motion, thereby driving the horizontal portion 651 to perform a linear reciprocating motion in the X direction, and the horizontal portion 651 can drive the connecting bracket 410 and the powder spreading assembly 400 to perform a linear reciprocating motion.

[0055] This driving mechanism is the most commonly used driving mechanism for the powder spreading device, and its control accuracy is higher than that of the driving mechanism in the first embodiment, and it will not be described here. Of course, the driving mechanism can also be replaced with other commonly used driving mechanisms such as a pneumatic piston driving structure or an electric push rod driving structure, and it is only necessary to directly or indirectly act on the connecting bracket 410 through the output end of the driving member 610.

[0056] Specifically, the driving member 610 is a servo motor, and the output end of the driving member 610 is connected in sequence to a reducer 620, a coupling 630 and a moving sprocket 640. The reducer 620 realizes the deceleration and torque increase of the driving member 610, and the coupling 630 realizes the smooth transition and torque transmission between the reducer 620 and the sprocket 640. The moving sprocket 640 cooperates with the sprocket 640 fixed on the inner wall of the vacuum box 500 to drive the drive chain 650 to move, thereby realizing the movement of the powder spreading assembly 400.

[0057] Specifically, a magnetic fluid sealing device is arranged between the output end of the coupling 630 and the moving sprocket 640. Under the action of a uniform and stable magnetic field, the magnetic fluid fills the set space and establishes a multi-stage "O-ring", thereby achieving a sealing effect, preventing dust from invading the gap of the coupling 630, and improving the operating stability of the equipment.

[0058] Optionally, the linear rails 100 are arranged in plurality along the second direction, each of the linear rails 100 is provided with the sliding member 200, and the plurality of sliding members 200 are fixedly connected to the connecting bracket 410, and the second direction is perpendicular to the first direction. The arrangement of the plurality of linear rails 100 and the corresponding sliding members 200 can further guide and limit the connecting bracket 410 and the powder spreading assembly 400, and can also prevent the powder spreading assembly 400 from rotating around a certain linear rail 100, thereby playing an anti-twisting role and improving the movement stability and powder spreading effect of the powder spreading assembly 400.

[0059] Embodiment 3

[0060] The difference between the third embodiment and the second embodiment is only the difference in the driving mechanism. Specifically, the driving mechanism in the second embodiment includes a driving member 610 arranged on the outer wall of the vacuum box 500, and the outer wall of at least one of the linear rails 100 is formed with a lead screw portion 110, and the lead screw portion 110 is connected with a lead screw nut (not shown in the figure), and the connecting bracket 410 is fixed with the lead screw nut, and the driving member 610 is used to drive the lead screw portion 110 to rotate. Specifically, the driving member 610 is a servo motor, and the output end of the servo motor is connected to a reducer 620 to achieve the deceleration and torque increase of the driving member 610. The structure of this driving mechanism is the most complex, and it is necessary to modify the existing powder spreading component 400 to a large extent, but the control accuracy is higher, and the powder spreading of the powder spreading component 400 can be accurately achieved, thereby improving the powder spreading effect.

[0061] Finally, this specific embodiment also provides an additive manufacturing device, which includes a powder spreading device as described in any of the above schemes. The additive manufacturing device can improve the lubrication performance of the sliding member 200, reduce the occurrence of jamming, and can also avoid the evaporation of lubricating oil caused by high temperature, and avoid the lubricating oil vapor from affecting the forming effect of the electron beam, thereby improving the printing performance of the additive manufacturing device, and increasing the service life and reliability of the powder spreading device, and reducing the maintenance cost of the additive manufacturing device.

[0062] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, various obvious changes, readjustments and substitutions can be made without departing from the protection scope of the present invention. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A powder spreading device, characterized in that: include: A linear track (100), wherein the linear track (100) is arranged to extend along a first direction; A sliding member (200), the sliding member (200) having a sliding cavity extending along a first direction, a surrounding wall forming the sliding cavity being slidably connected to the linear track (100), the sliding member (200) being fixedly connected to a powder spreading assembly (400), and first sealing members (310) being provided at both ends of the sliding member (200) along the first direction, the first sealing members (310) being used to seal a gap between the surrounding wall and the linear track (100); a telescopic tube (300), wherein the two ends of the sliding member (200) along the first direction are both provided with the telescopic tube (300), one end of the telescopic tube (300) is sealedly connected to the first sealing member (310), and the other end is correspondingly sealedly connected to the linear track (100), and the length of the telescopic tube (300) along the first direction is adjustable; A driving mechanism, wherein an output end of the driving mechanism is connected to the sliding member (200) or the powder spreading assembly (400).

2. The powder spreading device according to claim 1, characterized in that: The powder spreading device further comprises a vacuum box (500), both ends of the linear track (100) along the first direction are fixedly connected to the inner wall of the vacuum box (500), both ends of the linear track (100) along the first direction are provided with a second sealing member (320), one end of the second sealing member (320) is fixed to the inner wall of the vacuum box (500), and the other end is sealedly connected to the telescopic tube (300).

3. The powder spreading device according to claim 2, characterized in that: A hollow inner cavity is provided between the circumferential outer wall of the linear track (100) and the circumferential inner wall of the telescopic tube (300); the two hollow inner cavities are correspondingly connected to two air circuit connecting pipes (510) provided on the outer wall of the vacuum box (500); the driving mechanism comprises an air compression device, and the air circuit connecting pipes (510) are selectively connected to the air compression device.

4. The powder spreading device according to claim 2, characterized in that: The sliding member (200) is provided with a connecting bracket (410), and the powder spreading assembly (400) is fixedly connected to the connecting bracket (410).

5. The powder spreading device according to claim 4, characterized in that: The driving mechanism comprises a driving member (610) fixedly mounted on the inner wall of the vacuum box (500); a driving chain (650) is arranged at the output end of the driving member (610); the driving chain (650) is also wound around a sprocket (640) arranged on the inner wall of the vacuum box (500), so that at least a portion of the driving chain (650) is extended along the first direction and forms a horizontal portion (651); and the connecting bracket (410) is fixedly connected to the horizontal portion (651).

6. The powder spreading device according to claim 4, characterized in that: A plurality of the linear rails (100) are arranged at intervals along a second direction, each of the linear rails (100) is correspondingly provided with a sliding member (200), and a plurality of the sliding members (200) are fixedly connected to the connecting bracket (410), and the second direction is perpendicular to the first direction.

7. The powder spreading device according to claim 6, characterized in that: A lead screw portion (110) is formed on the outer wall of at least one of the linear rails (100), the lead screw portion (110) is cooperatively connected with a lead screw nut, the connecting bracket (410) is fixedly connected with the lead screw nut, and a driving member (610) is provided on the outer wall of the vacuum box (500), the driving member (610) being used to drive the lead screw portion (110) to rotate.

8. The powder spreading device according to any one of claims 1 to 7, characterized in that: The linear track (100) comprises an optical axis, and the sliding member (200) is a linear bearing; or, the linear track (100) is a slide rail, and the sliding member (200) is a slider.

9. The powder spreading device according to any one of claims 1 to 7, characterized in that: The maximum elongation of the telescopic tube (300) is not less than 20%, and the maximum compression of the telescopic tube (300) is not less than 55%.

10. Additive manufacturing equipment, characterized in that It comprises a powder spreading device as described in any one of claims 1-9.

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