Ventilation method of metal 3D printer and metal 3D printer

Abstract

The invention relates to the field of metal 3D printing, particularly provides an air exchange method of a metal 3D printer and the metal 3D printer, and aims to solve the problems of high air consumption and much time consumption of an existing air exchange method. In order to achieve the purpose, the ventilation method of the metal 3D printer comprises the steps that the density of protective gas and the density of air are compared, and a comparison result is obtained; and according to the comparison result, air exchange is achieved through an upward air exhaust method or a downward air exhaust method. Compared with a conventional method which only consumes a large amount of protective gas for a long time in the prior art, the ventilation method disclosed by the invention has the advantages that air is replaced by using an upward air exhaust method or a downward air exhaust method, and the purposes of quickly ventilating and saving the protective gas are achieved. The metal 3D printer has the same or corresponding technical characteristics as the ventilation method, so that the metal 3D printer can also achieve the purposes of rapid ventilation and protective gas saving.

Description

Technical Field

[0001] This invention relates to the field of metal 3D printing (additive manufacturing), specifically providing a ventilation method for a metal 3D printer and a metal 3D printer. Background Technology

[0002] Metal 3D printing is an advanced manufacturing technology that directly creates complex metal parts by depositing layers of metal material. It breaks through the limitations of traditional processing methods on the structural complexity of parts and is hailed as one of the core technologies of the "Third Industrial Revolution." Metal 3D printing technology can be divided into various processes according to different material forms and energy sources. Among them, SLS technology (Selective Laser Sintering) is one of the commercially mature mainstream technologies.

[0003] The current concept and method of air exchange in metal 3D printers using SLS technology involves adding a large amount of protective gas to the molding chamber, filter, and other chambers of the metal 3D printer while releasing a mixture of air and protective gas. Air exchange is achieved by gradually diluting the air content. This type of air exchange method has the disadvantages of high gas consumption and long time consumption.

[0004] Therefore, there is an urgent need to develop a ventilation method for metal 3D printers that can solve the above problems, as well as a metal 3D printer itself. Summary of the Invention

[0005] The present invention aims to solve the above-mentioned technical problems, namely, to solve the problems of high air consumption and long time consumption in existing ventilation methods.

[0006] In a first aspect, the present invention provides a ventilation method for a metal 3D printer, for discharging air from the molding chamber and / or filtration system of the metal 3D printer by inputting a protective gas, the ventilation method comprising: The density of the protective gas is compared with the density of air, and the comparison result is obtained; Based on the comparison results, ventilation can be achieved by either upward or downward air displacement.

[0007] In the preferred embodiment of the ventilation method for the above-mentioned metal 3D printer, the step of using an upward air displacement method or a downward air displacement method to achieve ventilation based on the comparison results is as follows: when the density of the protective gas is greater than the density of the air, the upward air displacement method is used to achieve ventilation.

[0008] In the preferred embodiment of the above-mentioned ventilation method for a metal 3D printer, the ventilation method of upward air discharge involves introducing the protective gas below the molding chamber and / or the filtration system of the metal 3D printer, and discharging the air above the molding chamber and / or the filtration system of the metal 3D printer.

[0009] In the preferred embodiment of the ventilation method for the above-mentioned metal 3D printer, the step of using the downward air displacement method to achieve ventilation based on the comparison results is: when the density of the protective gas is less than the density of the air, the downward air displacement method is used to achieve ventilation.

[0010] In the preferred embodiment of the above-mentioned ventilation method for a metal 3D printer, the ventilation method of downward air discharge involves introducing the protective gas above the molding chamber and / or the filtration system of the metal 3D printer, and discharging the air below the molding chamber and / or the filtration system of the metal 3D printer.

[0011] In a second aspect, the present invention also provides a metal 3D printer, the metal 3D printer comprising: The forming chamber includes an upper forming chamber and a lower forming chamber; The filtration system includes a cyclone dust collector and multiple filtration chambers, each of which is equipped with a corresponding filter. Three-way reversing valves are installed above and below the upper forming chamber, the lower forming chamber, the cyclone dust collector, and each filter chamber. Each three-way reversing valve has a P port, an A port, and a B port. The P port of the corresponding three-way reversing valve is connected to the corresponding forming chamber, the cyclone dust collector, and each filter chamber. The A ports of the corresponding three-way reversing valves are all connected to the protective air circuit, and the B ports of the corresponding three-way reversing valves are all connected to the exhaust pipe. The controller is configured to control the switching of each three-way directional valve; The upper forming chamber is connected to the cyclone dust collector and the multiple filter chambers through pipelines to form a circulation loop. The controller is configured to control the three-way reversing valve to switch directions based on the comparison between the density of the protective gas and the density of the air, so that the forming chamber and / or the filtration system can be ventilated by upward or downward air exhaust.

[0012] In the preferred technical solution of the above-mentioned metal 3D printer, when the density of the protective gas is greater than the density of the air, the controller controls the P port and A port of the three-way reversing valve below the upper molding chamber, the lower molding chamber, the cyclone dust collector, and / or each filter chamber to connect to the protective gas. At the same time, the controller controls the P port and B port of the three-way reversing valve above the lower molding chamber, the cyclone dust collector, and / or each filter chamber to achieve the upward air exhaust method.

[0013] In the preferred technical solution of the above-mentioned metal 3D printer, when the density of the protective gas is less than the density of the air, the controller controls the P port and A port of the three-way reversing valve above the upper molding chamber, the lower molding chamber, the cyclone dust collector, and / or each filter chamber to connect to the protective gas. At the same time, the controller controls the P port and B port of the three-way reversing valve below the lower molding chamber, the cyclone dust collector, and / or each filter chamber to achieve the downward air exhaust method.

[0014] In the preferred technical solution of the above-mentioned metal 3D printer, each three-way reversing valve is a pneumatic L-type three-way reversing valve.

[0015] In the preferred embodiment of the metal 3D printer described above, the metal 3D printer further includes valves, which are correspondingly disposed in each of the pipes, and the controller is further configured to control the opening and closing of the valves.

[0016] When employing the above technical solution, the ventilation method of the metal 3D printer of the present invention includes: comparing the density of the protective gas with the density of air, and obtaining a comparison result; based on the comparison result, ventilation is achieved by using an upward air displacement method or a downward air displacement method. Compared with the conventional method of the prior art that relies on long-term and large-scale consumption of protective gas, the ventilation method of the present invention uses an upward air displacement method or a downward air displacement method to replace air, achieving the purpose of rapid ventilation and saving protective gas. The metal 3D printer of the present invention has the same or corresponding technical features as the ventilation method, therefore, the metal 3D printer of the present invention can also achieve the purpose of rapid ventilation and saving protective gas. Attached Figure Description

[0017] The preferred embodiments of the present invention are described below with reference to the accompanying drawings, in which: Figure 1 This is a schematic structural diagram of a metal 3D printer according to an embodiment of the present invention; Figure 2 yes Figure 1 Enlarged schematic diagram of a portion of C; Figure 3 yes Figure 1 A magnified schematic diagram of a portion of D.

[0018] The symbols in the diagram represent the following meanings: 100 Metal 3D Printers 10. Molding silo, 11. Upper molding silo, 12. Lower molding silo. 20 Filtration system, 21 Cyclone dust collector, 22 Filtration chamber, 221 Medium-efficiency filter chamber, 222 High-efficiency filter chamber, 23 Filter, 24 Motor, 25 Piping. 30 Three-way directional valve 40 valves. Detailed Implementation

[0019] Preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Those skilled in the art should understand that these embodiments are merely illustrative of the technical principles of the present invention and are not intended to limit the scope of protection of the present invention. Those skilled in the art can make adjustments as needed to adapt to specific application scenarios.

[0020] It should be noted that in the description of this invention, terms such as "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," indicating directional or positional relationships, are based on the directional or positional relationships shown in the accompanying drawings. These are merely for ease of description and do not indicate or imply that the device or element must have a specific orientation, or be constructed and operated in a specific orientation; therefore, they should not be construed as limitations on this invention. Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0021] Furthermore, it should be noted that, in the description of this invention, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0022] See Figures 1-3 To address the problem that existing ventilation methods in metal 3D printers rely solely on prolonged and excessive consumption of protective gas, resulting in high gas consumption and long processing times, which does not comply with energy conservation and emission reduction policies, this invention provides a ventilation method for metal 3D printers. This method involves introducing protective gas to expel air from the forming chamber and / or filtration system of the metal 3D printer. The ventilation method includes: Step 100: Compare the density of the protective gas with the density of air, and obtain the comparison result; Step 200: Based on the comparison results, ventilation is achieved by either upward air displacement or downward air displacement.

[0023] The protective gas is an inert gas, usually nitrogen or argon, to meet the technical requirements of metal 3D printers printing different metals. Nitrogen and argon have densities that are higher and lower than air, respectively. The above-mentioned gas exchange scheme was designed to take into account the application scenarios of these two gases.

[0024] It should be noted that: "expelling air from the molding chamber and / or filtration system of a metal 3D printer" specifically refers to: expelling air from each component chamber in the molding chamber and filtration system of the metal 3D printer, or expelling air from the molding chamber of the metal 3D printer, or expelling air from a specific component chamber in the filtration system, or expelling air from several component chambers in the filtration system, depending on the specific operating conditions.

[0025] Compared to conventional methods that rely on long-term and large-scale consumption of protective gas, the ventilation method of this invention replaces air by using upward or downward air displacement based on the comparison between the density of the protective gas and the density of air, achieving rapid ventilation and saving protective gas, thus meeting the policy requirements of energy conservation and emission reduction.

[0026] Furthermore, the ventilation method of the present invention utilizes either upward or downward air displacement to replace air, thus accommodating both nitrogen and argon gases in various application scenarios.

[0027] As one possible implementation method, based on the comparison results, the steps of achieving air exchange by upward air displacement or downward air displacement are as follows: when the density of the protective gas is greater than the density of air, for example, when the protective gas is argon, the density of argon is greater than the density of air, the upward air displacement method is used to achieve air exchange.

[0028] As one possible implementation, the upward air exhaust method for ventilation involves introducing protective gas below the molding chamber and / or filtration system of the metal 3D printer and exhausting air above the molding chamber and / or filtration system of the metal 3D printer.

[0029] In one possible implementation, the forming chamber of a metal 3D printer includes an upper forming chamber and a lower forming chamber. The filtration system includes a cyclone dust collector, two filter chambers, and a motor. A medium-efficiency filter and a high-efficiency filter are installed in the two filter chambers respectively. Three-way reversing valves are installed above and below the upper forming chamber, lower forming chamber, cyclone dust collector, and the two filter chambers. Each three-way reversing valve has a P port, an A port, and a B port. The P port of each three-way reversing valve is connected to the corresponding forming chamber, cyclone dust collector, and each filter chamber. The A ports of each three-way reversing valve are connected to the protective air circuit, and the B ports of each three-way reversing valve are connected to the exhaust pipe. When the protective gas is argon, which has a density greater than that of air, the three-way reversing valves below the upper molding chamber, lower molding chamber, cyclone dust collector, and two filter chambers are driven by the control gas to connect port P to port A and introduce argon. At the same time, the three-way reversing valves above the upper molding chamber, lower molding chamber, cyclone dust collector, and two filter chambers are driven by the control gas to connect port P to port B. According to the air exchange command of the metal 3D printer, the air in the corresponding chamber is forced upward by the argon to the exhaust pipe.

[0030] As one possible implementation method, based on the comparison results, the steps of achieving ventilation by downward air displacement are as follows: when the density of the protective gas is less than the density of air, for example, when the protective gas is nitrogen, the density of nitrogen is less than the density of air, ventilation is achieved by downward air displacement.

[0031] As one possible implementation, the downward air exhaust method for ventilation involves introducing protective gas above the molding chamber and / or filtration system of the metal 3D printer and exhausting air below the molding chamber and / or filtration system of the metal 3D printer.

[0032] In one possible implementation, the forming chamber of a metal 3D printer includes an upper forming chamber and a lower forming chamber. The filtration system includes a cyclone dust collector, two filter chambers, and a motor. A medium-efficiency filter and a high-efficiency filter are installed in the two filter chambers respectively. Three-way reversing valves are installed above and below the upper forming chamber, lower forming chamber, cyclone dust collector, and the two filter chambers. Each three-way reversing valve has a P port, an A port, and a B port. The P port of each three-way reversing valve is connected to the corresponding forming chamber, cyclone dust collector, and each filter chamber. The A ports of each three-way reversing valve are connected to the protective air circuit, and the B ports of each three-way reversing valve are connected to the exhaust pipe. When the protective gas is nitrogen, which has a density less than that of air, the three-way reversing valves above the upper molding chamber, lower molding chamber, cyclone dust collector, and two filter chambers are driven by the control gas to connect port P to port A and introduce nitrogen. At the same time, the three-way reversing valves below the upper molding chamber, lower molding chamber, cyclone dust collector, and two filter chambers are driven by the control gas to connect port P to port B. According to the air exchange command of the metal 3D printer, the air in the corresponding chamber is forced downward by nitrogen to the exhaust pipe.

[0033] like Figure 1-3 As shown, to address the problem that existing metal 3D printers rely solely on long-term, large-volume consumption of protective gas for ventilation, resulting in high gas consumption and excessive time consumption, which does not meet energy conservation and emission reduction policy requirements, this invention provides a metal 3D printer 100. The metal 3D printer 100 includes: a forming chamber 10, a filtration system 20, and a controller. The forming chamber 10 includes an upper forming chamber 11 and a lower forming chamber 12. The filtration system 20 includes a cyclone dust collector 21, a motor 24, and multiple filter chambers 22. Each filter chamber 22 is equipped with a corresponding filter 23. For example, Figure 1 There are two filter chambers 22: one is a medium-efficiency filter chamber 221, which houses a medium-efficiency filter, and the other is a high-efficiency filter chamber 222, which houses a high-efficiency filter. Three-way reversing valves 30 are installed above and below the upper forming chamber 11, the lower forming chamber 12, the cyclone dust collector 21, and each filter chamber 22. Each three-way reversing valve 30 has a P port, an A port, and a B port. The P port of each three-way reversing valve 30 is connected to the corresponding forming chamber 10, the cyclone dust collector 21, and each filter chamber 22. The A ports of each three-way reversing valve 30 are connected to the protective air circuit, and the B ports of each three-way reversing valve 30 are connected to the exhaust pipe. The controller is configured to control the reversing of each three-way reversing valve 30. The upper forming chamber 11 is connected to the cyclone dust collector 21 and multiple filter chambers 22 through the pipeline 25 to form a circulation loop. The controller is configured to control the three-way reversing valve 30 to switch according to the density of the protective gas and the density of the air, so as to realize that the forming chamber 10 and / or the filter system 20 can be ventilated by the upward air exhaust method or the downward air exhaust method.

[0034] It should be noted that the air exchange in the forming chamber 10 and / or filtration system 20 of the metal 3D printer 100 specifically refers to: venting the air from each component chamber in the forming chamber 10 and filtration system 20 of the metal 3D printer 100; or venting the air from the upper forming chamber 11 and / or lower forming chamber 12 of the metal 3D printer 100; or venting the air from a specific component chamber in the cyclone dust collector 21, medium-efficiency filter, and high-efficiency filter in the filtration system 20; or venting the air from several component chambers in the cyclone dust collector 21, medium-efficiency filter, and high-efficiency filter in the filtration system 20, depending on the operating conditions. For example, after the upper forming chamber 11 has finished printing a part, only the upper forming chamber 11 can be ventilated. After replacing the medium-efficiency filter, only the medium-efficiency filter chamber 221 can be ventilated.

[0035] When adopting the above technical solution, the controller of the metal 3D printer 100 of the present invention is configured to control the three-way reversing valve 30 to switch directions based on a comparison of the density of the protective gas and the density of air, so as to realize that the molding chamber 10 and / or the filtration system 20 can be ventilated by either upward or downward air exhaust. Compared with the conventional method of the prior art that relies on long-term and large-scale consumption of protective gas, the metal 3D printer 100 of the present invention achieves the purpose of rapid ventilation and saving protective gas by using upward or downward air exhaust methods.

[0036] Furthermore, the metal 3D printer 100 of the present invention utilizes either upward or downward air displacement for ventilation, taking into account both nitrogen and argon gases, which can effectively reduce costs.

[0037] As one possible implementation method, such as Figure 1 As shown, each three-way directional valve 30 is a pneumatic L-type three-way directional valve 30.

[0038] As one possible implementation method, such as Figure 1 As shown, the metal 3D printer 100 also includes a valve 40, which is correspondingly installed in each pipe. The controller is also configured to control the opening and closing of the valve 40 to cooperate with the three-way reversing valve 30 to achieve air exchange.

[0039] As one possible implementation method, such as Figure 1 As shown, when the density of the protective gas is greater than the density of air, for example, if the protective gas is argon, ... Figure 3 As shown, the controller connects the P port and A port of the three-way reversing valve 30 below the upper molding chamber 11, lower molding chamber 12, cyclone dust collector 21, and / or each filter chamber 22 to introduce protective gas, i.e., argon. Figure 1As shown, the controller simultaneously controls the P port and B port of the three-way reversing valve 30 above the molding chamber 12, the cyclone dust collector 21 and / or each filter chamber 22 to connect, so as to realize the upward air exhaust method, that is, according to the air exchange command of the metal 3D printer 100, the air in the corresponding chamber is squeezed upward by argon gas to the exhaust pipe.

[0040] As one possible implementation, when the density of the protective gas is less than that of air, for example, when the protective gas is helium, see [reference needed]. Figure 3 The controller connects the P port and A port of the three-way reversing valve 30 above the upper molding chamber 11, lower molding chamber 12, cyclone dust collector 21, and / or each filter chamber 22 to introduce protective gas, i.e., helium. See [link / reference]. Figure 1 The controller simultaneously controls the P port and B port of the three-way reversing valve 30 below the molding chamber 12, the cyclone dust collector 21 and / or each filter chamber 22 to connect, so as to realize the downward air exhaust method, that is, according to the air exchange command of the metal 3D printer 100, the air in the corresponding chamber is squeezed downward by nitrogen to the exhaust pipe.

[0041] The technical solution of the present invention has been described in conjunction with the preferred embodiments shown in the accompanying drawings. However, it will be readily understood by those skilled in the art that the scope of protection of the present invention is obviously not limited to these specific embodiments. Without departing from the principles of the present invention, those skilled in the art can make equivalent changes or substitutions to the relevant technical features, and the technical solutions after these changes or substitutions will all fall within the scope of protection of the present invention.

Claims

1. A ventilation method for a metal 3D printer, characterized in that... The ventilation method is used to expel air from the molding chamber and / or filtration system of the metal 3D printer by inputting protective gas, and includes: The density of the protective gas is compared with the density of air, and the comparison result is obtained; Based on the comparison results, ventilation can be achieved by either upward or downward air displacement.

2. The ventilation method for a metal 3D printer according to claim 1, characterized in that... The step of using upward air displacement or downward air displacement to achieve ventilation based on the comparison results is as follows: when the density of the protective gas is greater than the density of the air, upward air displacement is used to achieve ventilation.

3. The ventilation method for a metal 3D printer according to claim 2, characterized in that... The method of using upward air exhaust for ventilation involves introducing the protective gas below the molding chamber and / or the filtration system of the metal 3D printer, and exhausting the air above the molding chamber and / or the filtration system of the metal 3D printer.

4. The ventilation method for a metal 3D printer according to claim 1, characterized in that... The step of using the downward air displacement method to achieve ventilation based on the comparison results is as follows: when the density of the protective gas is less than the density of the air, the downward air displacement method is used to achieve ventilation.

5. The ventilation method for a metal 3D printer according to claim 4, characterized in that... The method of using downward air exhaust for ventilation involves introducing the protective gas above the molding chamber and / or the filtration system of the metal 3D printer, and exhausting the air below the molding chamber and / or the filtration system of the metal 3D printer.

6. A metal 3D printer, characterized in that... The metal 3D printer includes: The forming chamber includes an upper forming chamber and a lower forming chamber. The filtration system includes a cyclone dust collector and multiple filtration chambers, each of which is equipped with a corresponding filter. Three-way reversing valves are installed above and below the upper forming chamber, the lower forming chamber, the cyclone dust collector, and each filter chamber. Each three-way reversing valve has a P port, an A port, and a B port. The P port of the corresponding three-way reversing valve is connected to the corresponding forming chamber, the cyclone dust collector, and each filter chamber. The A ports of the corresponding three-way reversing valves are all connected to the protective air circuit, and the B ports of the corresponding three-way reversing valves are all connected to the exhaust pipe. The controller is configured to control the switching of each three-way directional valve; The upper forming chamber is connected to the cyclone dust collector and the multiple filter chambers through pipelines to form a circulation loop. The controller is configured to control the three-way reversing valve to switch according to the density of the protective gas and the density of the air, so as to realize that the forming chamber and / or the filtration system can be ventilated by upward air exhaust or downward air exhaust.

7. The metal 3D printer according to claim 6, characterized in that... When the density of the protective gas is greater than the density of the air, the controller controls the P port and A port of the three-way reversing valve below the upper molding chamber, the lower molding chamber, the cyclone dust collector, and / or each filter chamber to connect to the protective gas. At the same time, the controller controls the P port and B port of the three-way reversing valve above the lower molding chamber, the cyclone dust collector, and / or each filter chamber to achieve the upward air exhaust method.

8. The metal 3D printer according to claim 6, characterized in that... When the density of the protective gas is less than the density of the air, the controller controls the P port and A port of the three-way reversing valve above the upper forming chamber, the lower forming chamber, the cyclone dust collector, and / or each filter chamber to connect to the protective gas. At the same time, the controller controls the P port and B port of the three-way reversing valve below the lower forming chamber, the cyclone dust collector, and / or each filter chamber to achieve the downward air discharge method.

9. The metal 3D printer according to claim 6, characterized in that... Each of the three-way directional valves is a pneumatic L-type three-way directional valve.

10. The metal 3D printer according to any one of claims 6-9, characterized in that... The metal 3D printer also includes valves, which are correspondingly disposed in each of the pipes, and the controller is further configured to control the opening and closing of the valves.

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