Forming cylinder device for laser selective melting and laser selective melting apparatus

Abstract

The application relates to a forming cylinder device for laser selective melting and a laser selective melting equipment, which comprises a forming cylinder body and a base plate mechanism, the forming cylinder body is provided with a cylindrical accommodating cavity; the base plate mechanism comprises a base plate body and a sealing assembly, the base plate body is adapted to the accommodating cavity and can move along the accommodating cavity, a plurality of gas flow channels are arranged in the base plate body; the sealing assembly comprises a first sealing ring, the first sealing ring is arranged on the sidewall of the base plate body and forms a sliding seal between the base plate body and the accommodating cavity; and the first sealing ring is lower than the height of the air outlet hole. According to the application, the airflow is sprayed along the air outlet angle to the accommodating cavity, the cylindrical structure of the accommodating cavity is matched, the sprayed airflow is rotated in the accommodating cavity, and the residual powder in the accommodating cavity is cleaned; due to the rotation of the gas, the powder on the cavity wall and in the gap is separated and blown out of the cavity, so that the problem of poor cleaning effect of the existing cleaning mode is effectively overcome, and the cleaning efficiency is higher.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of laser selective melting equipment, in particular to a forming cylinder device for laser selective melting and a laser selective melting equipment. BACKGROUND

[0002] In recent years, additive manufacturing technology has developed rapidly, and laser selective melting technology is a main technical approach in additive manufacturing technology. Laser selective melting technology uses laser as a heat source, melts metal powder from bottom to top layer by layer, and performs additive manufacturing by the principle of layer-by-layer stacking.

[0003] The laser selective melting equipment includes a forming cylinder and a substrate. The substrate is arranged in the forming cylinder and can be lifted along the height direction of the forming cylinder. Before forming, the substrate is lifted to the top end of the forming cylinder, the metal powder used for forming is laid on the substrate, and then the powder in the specified area is scanned according to the preset three-dimensional model slice by laser, so that the powder is melted and quickly cooled to solid. After completing the forming of this layer, the substrate is lowered and the steps of laying powder and melting powder in the specified area by laser are repeated again. After repeated for many times, the forming is completed.

[0004] Considering that the metal powder used in different forming processes is often not the same, after completing a forming, the forming cylinder needs to be cleaned. If cleaning is not performed or cleaning is not thorough, adverse consequences will occur. For example, the quality of the product of the next forming is reduced due to the use of different components of powder and impurities in the forming process.

[0005] Currently, the cleaning method for the forming cylinder is usually to first lift the substrate to the top end of the forming cylinder, then lower it to the bottom end, and then manually wipe the powder remaining in the inner wall of the forming cylinder with non-woven fabric wetted with alcohol. This process is repeated to clean the powder remaining in the gaps as much as possible. This method is not only inefficient, but also often difficult to completely clean the powder remaining in the corners and gaps. SUMMARY

[0006] Therefore, the technical problem to be solved by the present application is to overcome the low cleaning efficiency and the difficulty in achieving complete cleaning of the existing cleaning method for the powder remaining in the forming cylinder for laser selective melting. The present application provides a forming cylinder device for laser selective melting and a laser selective melting equipment. By cooperation of the substrate body including a gas flow channel and the sealing assembly, the remaining powder is cleaned by rotating airflow, which has good cleaning effect and high cleaning efficiency.

[0007] The application provides a forming cylinder device for selective laser melting, which comprises a forming cylinder body, a substrate mechanism and a sealing assembly.

[0008] In one embodiment of the present application, the substrate body comprises a first region and a second region arranged in sequence along the circumferential direction of the substrate body, the first region and the second region are arranged on the side wall of the substrate body; the sealing assembly further comprises a second sealing ring, the second sealing ring is arranged on the side wall of the substrate body and forms a sliding seal between the substrate body of the first region and the accommodating cavity, the height position of the gas outlet hole is lower than the height position of the second sealing ring; the first sealing ring and the second sealing ring can expand or contract in the radial direction of the substrate body, the first sealing ring and the second sealing ring both comprise an expanded state and a contracted state, when in the expanded state, the corresponding sealing ring expands and forms a sliding seal between the substrate body and the accommodating cavity; when in the contracted state, the corresponding sealing ring contracts and has a gap between the substrate body and the accommodating cavity; when the substrate mechanism is in the first cleaning state or in the second cleaning state, the first sealing ring is in the expanded state and the second sealing ring is in the contracted state; the substrate mechanism further comprises a third cleaning state and a fourth cleaning state; when the substrate mechanism is in the third cleaning state, the second sealing ring is in the expanded state and the first sealing ring is in the contracted state; the substrate body rises to the top end of the accommodating cavity and the gas flow channel sprays gas flow into the accommodating cavity, the gas flow rotates along the cavity wall of the accommodating cavity and blows the powder out of the second region out of the accommodating cavity; when the substrate mechanism is in the fourth cleaning state, the second sealing ring is in the expanded state and the first sealing ring is in the contracted state; the substrate body moves from the top end of the accommodating cavity to the bottom end of the accommodating cavity, while the gas flow channel sprays gas flow into the accommodating cavity, the gas flow rotates along the cavity wall of the accommodating cavity and blows the powder out of the second region out of the accommodating cavity.

[0009] In one embodiment of the present application, the sealing assembly further comprises a third sealing ring, the third sealing ring is arranged on the side wall of the substrate body and forms a sliding seal between the substrate body of the second region and the accommodating cavity, the height position of the third sealing ring is flush with the height position of the second sealing ring, the third sealing ring can also expand or contract in the radial direction of the substrate body and comprises the expanded state and the contracted state; when the substrate mechanism is in the first cleaning state, or the second cleaning state, or the third cleaning state, or the fourth cleaning state, the third sealing ring is in the contracted state; when forming, the first sealing ring, the second sealing ring and the third sealing ring are all in the expanded state.

[0010] In one embodiment of the present application, the area of the second region is 1 / 8-1 / 6 of the sum of the area of the first region and the area of the second region.

[0011] In one embodiment of the present application, the sidewall of the substrate body is provided with a receiving groove along the circumferential direction of the substrate body, the receiving groove is adapted to the first sealing ring, the second sealing ring and the third sealing ring, and the first sealing ring, the second sealing ring and the third sealing ring can be shrunk into the receiving groove and flush with the sidewall of the substrate when in the contracted state.

[0012] In one embodiment of the present application, the outflow angle A is set to 30°-60°.

[0013] In one embodiment of the present application, the outflow holes of the plurality of gas flow channels are uniformly distributed along the circumferential direction of the substrate body.

[0014] In one embodiment of the present application, a recovery mechanism is further included, the recovery mechanism comprises a suction assembly and a recovery component, the suction assembly is arranged at the top end of the forming cylinder, and the suction assembly is used to suck the powder blown out of the receiving cavity; the recovery component is detachably connected with the suction assembly, and the recovery component is used to store the powder sucked by the suction assembly.

[0015] In one embodiment of the present application, the recovery component is arranged below the suction assembly.

[0016] The present application also provides a laser selective melting device comprising the forming cylinder device for laser selective melting as described in any one of the above.

[0017] The above technical solutions of the present application have the following advantages compared with the prior art:

[0018] The forming cylinder device for laser selective melting provided by the application, by setting the cylindrical structure accommodating cavity and cooperating with the corresponding substrate mechanism, multiple gas flow channels are set on the substrate body to spray gas flow. The gas flow is sprayed to the accommodating cavity along the gas outlet angle, and cooperates with the cylindrical structure accommodating cavity, so that the sprayed gas flow rotates and sweeps and cleans inside the accommodating cavity at a certain speed, thereby cleaning the residual powder in the accommodating cavity; due to the continuous rotation of the gas, the powder in the cavity wall and the gaps of the accommodating cavity can be separated, and the powder is blown out of the cavity under the action of gas pressure, effectively overcoming the poor cleaning effect of the existing forming cylinder cleaning method, and the cleaning efficiency is also higher. At the same time, the setting of the first sealing ring can prevent the powder from falling into the accommodating cavity below the substrate under the premise of not interfering with the gas flow channel; in the process of moving the substrate body, the powder is scraped off the cavity wall, further ensuring the cleaning effect. After the forming is completed, the accommodating cavity is cleaned in the corresponding cleaning state by the forming cylinder device for laser selective melting provided by the application, effectively ensuring the cleaning effect and cleaning efficiency. BRIEF DESCRIPTION OF DRAWINGS

[0019] In order to make the content of the application more easily understood, the application will be further described in detail below according to specific embodiments of the application and in conjunction with the drawings, in which

[0020] Figure 1 It is a partial cross-sectional structure schematic view of a forming cylinder device for laser selective melting in a preferred embodiment of the application;

[0021] Figure 2 It is a structure schematic view of a substrate body in a preferred embodiment of the application;

[0022] Figure 3 It is a partial cross-sectional structure schematic view of a substrate body in a preferred embodiment of the application;

[0023] Figure 4 It is a structure schematic view of a substrate mechanism when a first sealing ring is in an expanded state in a preferred embodiment of the application;

[0024] Figure 5 It is a structure schematic view of a forming cylinder device for laser selective melting in a first cleaning state in a preferred embodiment of the application;

[0025] Figure 6 It is a structure schematic view of a forming cylinder device for laser selective melting in a second cleaning state in a preferred embodiment of the application;

[0026] Figure 7 It is a relationship schematic view of a first region and a second region in a preferred embodiment of the application;

[0027] Figure 8A schematic view of a substrate mechanism structure when another first seal ring is in an expanded state in a preferred embodiment of the present application;

[0028] Figure 9 A schematic view of a molding cylinder device for laser selective melting in a first cleaning state in a preferred embodiment of the present application;

[0029] Figure 10 A schematic view of a substrate mechanism structure when another second seal ring is in an expanded state in a preferred embodiment of the present application;

[0030] Figure 11 A schematic view of a molding cylinder device for laser selective melting in a third cleaning state in a preferred embodiment of the present application;

[0031] Figure 12 A schematic view of a molding cylinder device for laser selective melting in a fourth cleaning state in a preferred embodiment of the present application;

[0032] Figure 13 A schematic view of a substrate mechanism structure when another first seal ring is in an expanded state in a preferred embodiment of the present application;

[0033] Figure 14 A schematic view of a molding cylinder device for laser selective melting in a first cleaning state in a preferred embodiment of the present application;

[0034] Figure 15 A schematic view of a substrate mechanism structure when another second seal ring is in an expanded state in a preferred embodiment of the present application;

[0035] Figure 16 A schematic view of a molding cylinder device for laser selective melting in a third cleaning state in a preferred embodiment of the present application;

[0036] Figure 17 A schematic view of a substrate mechanism structure when molding is performed in a preferred embodiment of the present application;

[0037] Figure 18 A schematic view of a molding cylinder device for laser selective melting when molding is performed in a preferred embodiment of the present application;

[0038] Figure 19 A schematic view of another substrate body in a preferred embodiment of the present application;

[0039] Figure 20 A schematic view of another molding cylinder device for laser selective melting in a preferred embodiment of the present application;

[0040] Figure 21 A schematic view of a recovery mechanism in a preferred embodiment of the present application.

[0041] Explanation of the drawing marks: 10, forming cylinder body; 11, containing cavity; 20, base plate body; 21, gas flow channel; 211, gas outlet hole; 212, first flow channel part; 221, first area; 222, second area; 23, containing groove; 30, sealing assembly; 31, first sealing ring; 32, second sealing ring; 33, third sealing ring; 41, air suction assembly; 42, recycling component. DETAILED DESCRIPTION

[0042] The application will be further described below in conjunction with the drawings and specific embodiments, so that those skilled in the art can better understand the application and implement it, but the embodiments are not limiting to the application.

[0043] Referring to Figure 1 As shown in the drawings, the application discloses a forming cylinder device for laser selective melting, which comprises a forming cylinder body 10 and a base plate mechanism. The forming cylinder body 10 is provided with a containing cavity 11 along the height direction of the forming cylinder body 10, and the containing cavity 11 is provided in a cylindrical structure. The containing cavity 11 is used to cooperate with the base plate to realize laser selective melting of metal powder layer by layer from top to bottom. By setting the containing cavity 11 in a cylindrical structure, the gas flow of the base plate mechanism can be well adapted, so that the gas flow rotates inside the cylindrical containing cavity 11, sweeps and cleans the powder attached in the cavity, and effectively solves the problem of powder residue in the containing cavity 11.

[0044] Referring to Figure 2 As shown in the drawings, the base plate mechanism comprises a base plate body 20 and a sealing assembly 30, and the base plate body 20 is also provided in a cylindrical structure to adapt to the containing cavity 11 so as to realize the forming function. The radial dimension of the base plate body 20 is smaller than the radial dimension of the containing cavity 11, that is, there is a certain gap between the side wall of the base plate body 20 and the cavity wall of the containing cavity 11. The base plate body 20 can move up and down along the height direction of the containing cavity 11, and different ways of realizing the up and down movement can be selected according to different requirements, such as cylinder, motor combined with screw rod, etc., which will not be described in detail; preferably, the lifting driving component is connected with the lower end surface of the base plate body 20 instead of the upper end surface, so as to avoid interference with the forming. A plurality of gas flow channels 21 are arranged in the base plate body 20, and the gas flow channels 21 are used to spray gas flow to sweep and clean the powder by the gas flow. How to realize the spraying of gas flow will not be described in detail, and preferably, a gas pipe communicating with the gas flow channels 21 is arranged on the lower end surface of the base plate body 20, and the gas pipe is connected with a gas pump; the gas pump can be arranged outside the forming cylinder body 10 or in the containing cavity 11 according to requirements. Figure 3As shown, each gas flow channel 21 includes an outlet hole 211, and a first flow channel part 212 communicating with the outlet hole 211, and the outlet hole 211 is arranged on the side wall of the substrate body 20. Preferably, the remaining structure of each gas flow channel 21 is also the same, and each gas flow channel 21 is in the same horizontal plane to achieve the best space utilization. The outlet hole 211 and the axis of the substrate body 20, the extension direction in which the two are in a straight line, and the extension direction of the first flow channel part 212 form an outlet included angle A, and the outlet included angle A is an acute angle. Through the arrangement of the structure, the gas flow is neither sprayed along the radial direction of the substrate body 20 nor sprayed along the tangential direction of the substrate body 20, but is sprayed at a certain angle along the outlet included angle, cooperates with the cylindrical structure of the containing cavity 11, and can make the sprayed gas flow rotate and blow and clean inside the containing cavity 11 at a certain speed, thereby cleaning the powder remaining in the containing cavity 11; due to the continuous rotation of the gas, the powder in the gaps on the cavity wall of the containing cavity 11 can be separated and blown out of the cavity under the action of gas pressure, effectively overcoming the poor cleaning effect of the existing forming cylinder cleaning method, and the cleaning efficiency is also higher. Preferably, the gas flow channel 21 is arranged in a curved flow channel structure.

[0045] Referring to Figure 4 As shown, the sealing assembly 30 includes a first sealing ring 31 arranged on the side wall of the substrate body 20 and forming a sliding seal between the substrate body 20 and the containing cavity 11. Preferably, an o-shaped sealing ring is used, and the containing cavity 11, the sealing ring and the substrate body 20 are in interference fit. For the sliding seal, that is, the sealing ring can still ensure sealing when moving relative to the cavity wall of the containing cavity 11, similar to the relationship between the needle cylinder piston and the needle cylinder wall, which is a prior art, and the first sealing ring 31 can be selected according to actual needs, and will not be described in detail. The height position of the first sealing ring 31 is lower than the height position of the outlet hole 211. For the arrangement of the first sealing ring 31, it can ensure that the normal gas flow of the outlet hole 211 is not affected, and the cleaning effect is guaranteed; secondly, it can prevent powder from falling into the containing cavity 11 below the substrate body 20, and ensure that there is no powder deposition at the bottom end of the containing cavity 11; thirdly, it can realize powder scraping with the cavity wall of the containing cavity 11 during the movement of the substrate body 20, and further guarantee the cleaning effect.

[0046] The forming cylinder device for selective laser melting provided by the application includes a first cleaning state and a second cleaning state. Referring to Figure 5As shown, when the substrate mechanism is in the first cleaning state, the substrate body 20 is lowered to the bottom end of the containing cavity 11, and the gas flow channel 21 sprays a gas flow into the containing cavity 11, which rotates along the cavity wall of the containing cavity 11 to clean the powder in the cavity, and the powder is blown out of the containing cavity 11 under the action of the gas flow. The powder in the containing cavity 11 above the substrate body 20 can be cleaned by the first cleaning state. Referring to Figure 6 As shown, when the substrate mechanism is in the second cleaning state, the substrate body 20 moves from the bottom end of the containing cavity 11 to the top end of the containing cavity 11, and the gas flow channel 21 sprays a gas flow into the containing cavity 11, which rotates along the cavity wall of the containing cavity 11 and blows the powder out of the containing cavity 11. In the second cleaning state, the substrate body 20 moves upward while spraying a gas flow through the gas flow channel 21, so that the strong gas flow can closely contact the cavity wall of the containing cavity 11, and the cleaning effect is better than that of the first cleaning state. Preferably, after molding, the first cleaning state is used for cleaning, and then the second cleaning state is used for further cleaning to ensure the cleaning effect.

[0047] The forming cylinder device for laser selective melting disclosed in the present application is provided with a cylindrical containing cavity 11 and a corresponding substrate mechanism, and a plurality of gas flow channels 21 are opened on the substrate body 20 to spray a gas flow. The gas flow is sprayed into the containing cavity 11 along the gas outlet angle, and the cylindrical containing cavity 11 can make the sprayed gas flow rotate and clean at a certain speed inside the containing cavity 11, so as to clean the powder remaining in the containing cavity 11; due to the continuous rotation of the gas, the powder in the gaps on the cavity wall of the containing cavity 11 can be separated, and the powder can be blown out of the cavity under the action of gas pressure, effectively overcoming the poor cleaning effect of the existing forming cylinder cleaning method, and the cleaning efficiency is also higher. At the same time, the first sealing ring 31 is provided, which can prevent the powder from falling into the containing cavity 11 below the substrate body 20 without interfering with the gas flow channel 21, so as to ensure that there is no powder deposition at the bottom end of the containing cavity 11; during the movement of the substrate body 20, the powder on the cavity wall of the containing cavity 11 is scraped, further ensuring the cleaning effect. After molding is completed, the containing cavity 11 is cleaned by the forming cylinder device for laser selective melting disclosed in the present application in the corresponding cleaning state, effectively ensuring the cleaning effect and cleaning efficiency.

[0048] The forming cylinder device for selective laser melting, in some embodiments, the substrate body 20 comprises a first area 221 and a second area 222 arranged in sequence along the circumferential direction of itself, and the first area 221 and the second area 222 are arranged on the side surface of the substrate body 20. The definition of the first area 221 and the second area 222 is only for the convenience of understanding the structure of the second sealing ring 32. Preferably, taking the axis of the substrate body 20 as the reference, in the horizontal plane perpendicular to the axis of the substrate body 20, two straight lines intersecting with the axis of the substrate body 20 are taken, the intersection points of the two straight lines with the side surface of the substrate body 20 are connected into two horizontal line segments on the side surface of the substrate body 20; respectively taking the two intersection points as the end points, making two equal-length vertical line segments along the height axis of the substrate body 20, connecting the end points of the vertical line segments with the end points of the other vertical line segments, thereby obtaining the first area 221 and the second area 222 on the side wall of the substrate body 20. Referring to Figure 7 It is shown that the structure of the first area 221 and the second area 222 in the horizontal plane is respectively shown, and it should be noted that the first area 221 and the second area 222 in the figure refer to the side wall of the substrate body 20, not the two dotted areas, and the dotted areas are only used to more intuitively understand the relative relationship between the two areas. The specific area of the first area 221 and the second area 222 can be set according to actual needs; preferably, in the case that the width of the two areas is consistent, that is, the size of the two areas in the height direction of the substrate body 20 is the same, the area of the first area 221 is larger than that of the second area 222.

[0049] Referring to Figure 8As shown, the sealing assembly 30 further comprises a second sealing ring 32, which is arranged on the sidewall of the substrate body 20 and forms a sliding seal between the substrate body 20 and the accommodating cavity 11 in the first region 221, and the height position of the gas outlet hole 211 is lower than that of the second sealing ring 32. Preferably, the second sealing ring 32 has a C-shaped structure, and the rest is the same as the first sealing ring 31 and will not be described in detail. In addition to scraping the powder on the cavity wall, the height position of the second sealing ring 32 can also achieve cleaning of the accommodating cavity 11 below the substrate body 20. Specifically, the first sealing ring 31 and the second sealing ring 32 can both expand or contract in the radial direction of the substrate body 20, and preferably the first sealing ring 31 and the second sealing ring 32 are arranged as inflatable sealing rings. The sealing ring that can expand or contract is prior art, and the principle will not be described. The gas path can also be set according to actual needs. Similarly, the structure of the contact surface between the sealing ring and the cavity wall of the accommodating cavity 11 can also be set differently, such as a groove structure, a pattern structure, etc. The first sealing ring 31 and the second sealing ring 32 both include an expanded state and a contracted state. When in the expanded state, the corresponding sealing ring expands and forms a sliding seal between the substrate body 20 and the accommodating cavity 11. When in the contracted state, the corresponding sealing ring contracts and has a gap between the substrate body 20 and the accommodating cavity 11. By controlling the expansion and contraction of the two sealing rings, the rest of the accommodating cavity 11 can be cleaned.

[0050] Referring to Figure 9 As shown, when the substrate mechanism is in the first cleaning state or in the second cleaning state, the first sealing ring 31 is in the expanded state and the second sealing ring 32 is in the contracted state, so as to avoid the second sealing ring 32 from hindering the upward rotation of the gas flow and ensuring the cleaning effect.

[0051] The substrate mechanism further comprises a third cleaning state and a fourth cleaning state. Referring to Figure 10 and Figure 11 As shown, when the substrate mechanism is in the third cleaning state, the second sealing ring 32 is in the expanded state and the first sealing ring 31 is in the contracted state; the substrate body 20 is lifted to the top end of the accommodating cavity 11 and the gas flow is sprayed into the accommodating cavity 11 by the gas flow channel 21, and the gas flow rotates along the cavity wall of the accommodating cavity 11 and blows the powder out of the accommodating cavity 11. It can be imagined that although in the case of not arranging the second sealing ring 32 and only arranging the first sealing ring 31 as a sealing ring that can expand and contract, the cleaning of the bottom end of the accommodating cavity 11 can also be achieved to a certain extent, but due to the gap between the substrate body 20 and the accommodating cavity 11, the lack of blocking will cause the gas flow to overflow too much, the pressure difference between the upper and lower parts of the substrate body 20 will decrease, and the cleaning ability of the residual powder in the lower accommodating cavity 11 will be affected. Referring to Figure 10 and Figure 12As shown, when the substrate mechanism is in the fourth cleaning state, the second sealing ring 32 is in the expanded state and the first sealing ring 31 is in the contracted state; the substrate body 20 moves from the top end of the containing cavity 11 to the bottom end of the containing cavity 11, and at the same time, the gas flow is sprayed into the containing cavity 11 by the gas flow channel 21, the gas flow rotates along the cavity wall of the containing cavity 11 and blows the powder out of the containing cavity 11 from the second area 222. Through the fourth cleaning state, the substrate body 20 moves downward while spraying the gas flow by the gas flow channel 21, so that the strong gas flow can be in close contact with the cavity wall of the containing cavity 11, and the cleaning effect on the bottom end of the containing cavity 11 is better than that of the third cleaning state. Preferably, the cleaning is first performed by the third cleaning state and then further cleaned by the fourth cleaning state to ensure the cleaning effect. After cleaning through the fourth cleaning state, the first cleaning state and the second cleaning state can also be used for cleaning.

[0052] Although the first cleaning state and the second cleaning state can clean the containing cavity 11 above the substrate body 20, there will still be some residual powder in the containing cavity 11 below the substrate body 20, especially in the bottom end of the containing cavity 11, in the case of long-term use. If the powder is not cleaned, the powder will be deposited in the bottom end of the containing cavity 11, which will hinder the movement of the substrate body 20, etc. Therefore, by providing the first sealing ring 31 and the second sealing ring 32 which can expand and contract, the substrate mechanism can clean the residual powder in the bottom end of the containing cavity 11 through the third cleaning state and the fourth cleaning state, further ensuring the cleaning effect.

[0053] Referring to Figure 13 and Figure 15 As shown, in some embodiments, the forming cylinder device for laser selective melting provided by the present application further comprises a third sealing ring 33, which is arranged on the side wall of the substrate body 20 and forms a sliding seal between the substrate body 20 and the containing cavity 11 of the second area 222. The height position of the third sealing ring 33 is flush with the height position of the second sealing ring 32, and the third sealing ring 33 can also expand or contract along the radial direction of the substrate body 20 and comprises the expanded state and the contracted state. The structure of the third sealing ring 33 is similar to that of the second sealing ring 32, but the third sealing ring 33 is arranged as an arc-shaped sealing ring instead of a c-shaped sealing ring like the second sealing ring 32, so as to adapt to the second area 222. Referring to Figure 14 and Figure 16 As shown, when the substrate mechanism is in the first cleaning state, or the second cleaning state, or the third cleaning state, or the fourth cleaning state, the third sealing ring 33 is in the contracted state, so as to avoid hindering the gas flow from blowing the powder out of the containing cavity 11. Referring to Figure 17 andFigure 18 As shown, when forming, the first sealing ring 31, the second sealing ring 32 and the third sealing ring 33 are all in the expanded state to avoid powder entering the gas flow channel 21 or the bottom end of the containing cavity 11. Considering that in the case that both the first sealing ring 31 and the second sealing ring 32 can expand, when cleaning, since the second area 222 needs to be kept in communication with the outside of the containing cavity 11 to blow out the powder in the containing cavity 11 to achieve cleaning, at the same time, the keeping of the second area 222 will cause the powder to contact the gas flow channel 21 during forming, resulting in unnecessary waste and pollution. Therefore, by setting the third sealing ring 33 to close the second area 222 during forming, the powder entering the gas flow channel 21 is effectively avoided.

[0054] In some embodiments of the forming cylinder device for laser selective melting according to the present application, the area of the second area 222 accounts for 1 / 8-1 / 6 of the sum of the area of the first area 221 and the area of the second area 222. Under the preferred conditions of the first area 221 and the second area 222 described above, it can also be understood that the arc length corresponding to the second area 222 accounts for 1 / 8-1 / 6 of the circumference of the circle where the arc length is located. When greater than 1 / 6, the resistance of the second sealing ring 32 to the airflow becomes smaller, the overflow of the airflow becomes more, the air pressure difference between the top and bottom of the substrate body 20 becomes smaller, which will cause the cleaning ability of the airflow to the residual powder in the corners of the containing cavity 11 to become worse. When less than 1 / 8, the resistance of the second sealing ring 32 to the airflow becomes larger, the air pressure difference between the top and bottom of the substrate body 20 becomes larger, the gas flow rate becomes larger, which will cause the airflow carrying powder to wash the inner wall of the forming cylinder to cause severe wear, reducing the service life of the forming cylinder. Preferably, it is 1 / 7, taking into account the cleaning ability and service life.

[0055] Referring to Figure 19 As shown, in some embodiments of the forming cylinder device for laser selective melting according to the present application, the sidewall of the substrate body 20 is provided with a containing groove 23 along the circumferential direction of itself, the containing groove 23 is adapted to the first sealing ring 31, the second sealing ring 32 and the third sealing ring 33, and when in the contracted state, the first sealing ring 31, the second sealing ring 32 and the third sealing ring 33 can all be contracted into the containing groove 23 and flush with the sidewall of the substrate. By providing the containing groove 23, when in the contracted state, each sealing ring can be contracted into the containing groove 23, further ensuring the gap size between the substrate body 20 and the cavity wall of the containing cavity 11, avoiding the obstruction of the airflow by the sealing ring, and ensuring the cleaning effect and cleaning efficiency.

[0056] Referring to Figure 3As shown, in some embodiments of the forming cylinder device for laser selective melting according to the present application, the gas outlet angle A is set to 30°-60°. Orthogonal decomposition analysis of the airflow as a vector shows that when the angle is less than 30°, the radial velocity component becomes larger, the tangential velocity component becomes smaller, and the airflow rotation effect becomes poor, which is not conducive to the effect of blowing powder by the airflow. When the angle is greater than 60°, the tangential velocity component becomes larger, the radial velocity component becomes smaller, and the airflow sweeping effect on the side wall of the forming cylinder becomes poor, which is not conducive to the effect of cleaning the residual powder in the corners of the forming cylinder. The optimal solution for the angle is 45°, which takes into account the tangential velocity and the radial velocity, and can improve the effect of blowing powder and clean the residual powder in the corners of the forming cylinder.

[0057] In some embodiments of the forming cylinder device for laser selective melting according to the present application, the gas outlet holes 211 of the plurality of gas flow channels 21 are uniformly distributed along the circumferential direction of the substrate body 20. Through uniform distribution, the cleaning effect is optimal, and the cleaning efficiency is improved.

[0058] Referring to Figure 20 and Figure 21 As shown, in some embodiments of the forming cylinder device for laser selective melting according to the present application, the forming cylinder device further comprises a recycling mechanism, which comprises an air suction assembly 41 and a recycling component 42. The air suction assembly 41 is arranged at the top end of the forming cylinder and is used to suck the powder blown out of the containing cavity 11. The recycling component 42 is detachably connected with the air suction assembly 41 and is used to store the powder sucked by the air suction assembly 41. Considering that the powder blown out of the containing cavity 11 will be unnecessarily wasted and polluted, the powder is sucked by the air suction assembly 41. The air suction assembly 41 is a prior art and will not be described in detail. At the same time, the recycling component 42 is arranged to collect and store the sucked powder, so as to be recycled again and reduce the forming cost. According to actual needs, a recycling bottle or a recycling bag can be selected, and the detachable connection facilitates replacement after collection.

[0059] Referring to Figure 21 As shown, in some embodiments of the forming cylinder device for laser selective melting according to the present application, the recycling component 42 is arranged below the air suction assembly 41. Through the limitation of this structure, the powder sucked by the air suction assembly 41 can fall into the recycling component 42 by gravity, which is energy-saving and environmentally friendly.

[0060] The present application discloses a laser selective melting equipment comprising the forming cylinder device for laser selective melting according to any one of the above embodiments. The laser selective melting equipment according to the present application has the advantages of the forming cylinder device for laser selective melting according to the above embodiments, and therefore all the advantages of the laser selective melting equipment are also possessed, which will not be described again.

[0061] Working principle:

[0062] After the molding is completed, the powder in the containing cavity 11 is cleaned by different cleaning states. Taking a cleaning process as an example, after the molding is completed, the substrate body 20 is usually at the middle position of the containing cavity 11, so the bottom end of the containing cavity 11 below the substrate body 20 is cleaned by the fourth cleaning state first. After the substrate body 20 is lowered to the bottom end of the containing cavity 11, the containing cavity 11 above the substrate body 20 is cleaned by the first cleaning state. Subsequently, the containing cavity 11 above the substrate body 20 is cleaned again by the second cleaning state. Finally, the containing cavity 11 below the substrate body 20 is cleaned by the fourth cleaning state.

[0063] In different cleaning states, the gas flow channel 21 sprays gas flow to the containing cavity 11, and the gas flow rotates along the cylindrical structure of the containing cavity 11 to separate the powder; under the action of gas pressure, the gas flow blows the powder out of the containing cavity 11 upwards. At this time, the powder is absorbed by the air suction assembly 41 to avoid pollution, and falls into the recycling component 42 for subsequent secondary use.

[0064] Obviously, the above embodiments are only examples for the purpose of clarity, and are not limiting of the embodiments. For those skilled in the art, other different forms of changes or variations can be made on the basis of the above description. Here, it is not necessary and impossible to exhaust all the embodiments. The obvious changes or variations derived therefrom are still within the protection scope of the present application.

Claims

1. A forming cylinder device for laser selective melting, characterized in that, include: A forming cylinder body, wherein the forming cylinder body is provided with a receiving cavity along its own height direction, and the receiving cavity is configured as a cylindrical structure; A substrate mechanism includes a substrate body and a sealing assembly. The substrate body is configured as a cylindrical structure and adapted to the receiving cavity. The substrate body is movable along the height direction of the receiving cavity. Multiple gas channels are provided within the substrate body for ejecting gas flow. Each gas channel includes an outlet and a first channel portion communicating with the outlet. The outlet is located on the side wall of the substrate body. The extension direction of the straight line connecting the outlet and the axis of the substrate body forms an outlet angle A with the extension direction of the first channel portion. The outlet angle A is an acute angle. The sealing assembly includes a first sealing ring located on the side wall of the substrate body and forming a sliding seal between the substrate body and the receiving cavity. The height of the first sealing ring is lower than the height of the outlet. The substrate mechanism includes a first cleaning state and a second cleaning state. When the substrate mechanism is in the first cleaning state, the substrate body descends to the bottom of the receiving cavity and airflow is ejected into the receiving cavity through the gas flow channel. The airflow rotates along the cavity wall and blows the powder out of the receiving cavity. When the substrate mechanism is in the second cleaning state, the substrate body moves from the bottom of the receiving cavity to the top of the receiving cavity, and airflow is ejected into the receiving cavity through the gas flow channel. The airflow rotates along the cavity wall and blows the powder out of the receiving cavity.

2. The forming cylinder device for laser selective melting according to claim 1, characterized in that: The substrate body includes a first region and a second region arranged sequentially along its own circumference, and the first region and the second region are disposed on the side surface of the substrate body. The sealing assembly further includes a second sealing ring, which is disposed on the side wall of the substrate body and forms a sliding seal between the substrate body and the receiving cavity in the first region. The height of the vent hole is lower than the height of the second sealing ring. Both the first sealing ring and the second sealing ring are capable of expanding or contracting radially along the substrate body. Both the first sealing ring and the second sealing ring include an expanded state and a contracted state. When in the expanded state, the corresponding sealing ring expands and forms a sliding seal between the substrate body and the receiving cavity. When in the contracted state, the corresponding sealing ring contracts and creates a gap between the substrate body and the receiving cavity. When the substrate mechanism is in the first cleaning state or the second cleaning state, the first sealing ring is in the expanded state and the second sealing ring is in the contracted state; The substrate mechanism also includes a third cleaning state and a fourth cleaning state; When the substrate mechanism is in the third cleaning state, the second sealing ring is in the expanded state and the first sealing ring is in the contracted state; the substrate body rises to the top of the receiving cavity and airflow is ejected into the receiving cavity through the gas flow channel. The airflow rotates along the cavity wall of the receiving cavity and blows the powder out of the receiving cavity from the second region. When the substrate mechanism is in the fourth cleaning state, the second sealing ring is in the expanded state and the first sealing ring is in the contracted state; the substrate body moves from the top of the receiving cavity to the bottom of the receiving cavity, and at the same time, airflow is ejected into the receiving cavity from the gas flow channel. The airflow rotates along the cavity wall of the receiving cavity and blows the powder out of the receiving cavity from the second region.

3. The forming cylinder device for laser selective melting according to claim 2, characterized in that: The sealing assembly further includes a third sealing ring, which is disposed on the side wall of the substrate body and forms a sliding seal between the substrate body and the receiving cavity in the second region. The height of the third sealing ring is flush with the height of the second sealing ring. The third sealing ring can also expand or contract radially along the substrate body, and includes the expanded state and the contracted state. When the substrate mechanism is in the first cleaning state, or the second cleaning state, or the third cleaning state, or the fourth cleaning state, the third sealing ring is in the contracted state. During the molding process, the first sealing ring, the second sealing ring, and the third sealing ring are all in the expanded state.

4. The forming cylinder device for laser selective melting according to claim 2 or 3, characterized in that: The area of ​​the second region is 1 / 8 to 1 / 6 of the sum of the areas of the first region and the second region.

5. The forming cylinder device for laser selective melting according to claim 3, characterized in that: A receiving groove is provided on the side wall of the substrate body along its own circumferential direction. The receiving groove is adapted to the first sealing ring, the second sealing ring and the third sealing ring. When in the contracted state, the first sealing ring, the second sealing ring and the third sealing ring can all be contracted into the receiving groove and are flush with the side wall of the substrate.

6. The forming cylinder device for laser selective melting according to claim 1, characterized in that: The exhaust angle A is set to 30°-60°.

7. The forming cylinder device for laser selective melting according to claim 1, characterized in that: The gas outlet holes of the plurality of gas channels are evenly distributed along the circumferential direction of the substrate body.

8. The forming cylinder device for laser selective melting according to claim 1, characterized in that, It also includes a recycling mechanism, which includes an air intake assembly and a recycling component. The air intake assembly is disposed at the top of the forming cylinder and is used to suck up powder blown out of the receiving cavity. The recycling component is detachably connected to the air intake assembly and is used to store the powder sucked up by the air intake assembly.

9. The forming cylinder device for laser selective melting according to claim 8, characterized in that: The recovery component is located below the air intake assembly.

10. A laser selective melting device, characterized in that, Includes the forming cylinder device for laser selective melting as described in any one of claims 1-9.

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