A method of oxygen removal for an additive manufacturing apparatus

Abstract

The application discloses a kind of oxygen removal methods of additive manufacturing equipment, S1, first valve, second valve and exhaust valve are closed, and inlet valve is opened, inert gas is filled into printing cabin, when printing cabin pressure increases to first pressure set threshold, inlet valve is closed and exhaust valve is opened, mixed gas in printing cabin is discharged outward, and exhaust valve is closed when printing cabin pressure reduces to second pressure set threshold;S2, repeat operation step S1 multiple times until the oxygen content in printing cabin reduces to oxygen content set threshold, open first valve and second valve and start fan, close fan, first valve and second valve after fan runs for a period of time, complete the replacement of air in fan, air suction pipe and air blowing pipe and inert gas in printing cabin, repeat operation step S1 multiple times again, complete the oxygen removal work of additive manufacturing equipment.The application can remove oxygen in printing cabin in very short time, and can greatly reduce the oxygen removal time of additive manufacturing equipment in early stage.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of 3D printing, and particularly relates to a deoxygenation method of an additive manufacturing device. BACKGROUND

[0002] 3D printing is a kind of rapid prototyping technology, also known as additive manufacturing, which is a technology for constructing objects through layer-by-layer printing based on digital model files, using powder-like metal or plastic and other bondable materials. 3D printing is usually realized by using a digital technology material printer, and is often used for manufacturing models in the fields of mold manufacturing and industrial design. Gradually, it is used for direct manufacturing of actual products. There are parts printed by using 3D printing technology. 3D printing technology is applied in the fields of jewelry, footwear, industrial design, architecture, engineering and construction, automobiles, aerospace, dental and medical industry, education, geographic information system, civil engineering, guns and other fields. Metal 3D printing technology, as a new type of intelligent manufacturing technology, shows strong development momentum in more fields such as equipment design and manufacturing, equipment support, aerospace and the like.

[0003] Currently, the 3D printing device, i.e. the additive manufacturing device, has the problem that the time for the preliminary preparation work is too long, resulting in too long waiting time for printing. In particular, the deoxygenation work of the additive manufacturing device is particularly obvious in the preliminary preparation work. The inert gas is injected while the exhaust is performed. Specifically, the inert gas inlet valve and the exhaust valve connected with the printing cabin of the additive manufacturing device are opened at the same time to discharge the air in the printing cabin of the additive manufacturing device by means of inert gas replacement. However, the deoxygenation efficiency is low by means of injecting inert gas while exhausting. Moreover, when the fan is started, the fan blows the air in the pipeline into the printing cabin and sucks the mixed gas of the inert gas and the air in the printing cabin into the pipeline, which causes the air in the printing cabin to not be smoothly discharged from the exhaust valve, thereby further reducing the deoxygenation efficiency of the additive manufacturing device. The deoxygenation time needs 30 min to 1 h. For large additive manufacturing devices, the deoxygenation operation needs several hours. SUMMARY

[0004] In view of the defects of the prior art, the present application provides a deoxygenation method of an additive manufacturing device, which can remove the oxygen in the printing cabin in a very short time, greatly reduce the deoxygenation time of the additive manufacturing device in the preliminary stage, and greatly improve the efficiency of the preliminary preparation work of the additive manufacturing device.

[0005] The technical scheme adopted by the present application to solve the technical problems is as follows:

[0006] A kind of oxygen removal method of additive manufacturing equipment, the printing cabin of the additive manufacturing equipment is equipped with air inlet valve and exhaust valve, printing cabin is connected with the air inlet of fan by suction pipe with first valve, and is connected with the air outlet of fan by blowing pipe with second valve, the oxygen removal method includes the following steps:

[0007] S1, the first valve, second valve and exhaust valve are closed and air inlet valve is opened, inert gas in the inert gas bottle connected with the air inlet valve is filled into printing cabin, and the pressure in the printing cabin is detected in real time by pressure sensor, when the pressure in the printing cabin increases to first pressure set threshold, the air inlet valve is closed and exhaust valve is opened, the mixed gas of inert gas and air in the printing cabin is discharged outward, when the pressure in the printing cabin reduces to second pressure set threshold, exhaust valve is closed, and the oxygen content in the printing cabin is detected by oxygen content sensor;

[0008] S2, repeat operation step S1 multiple times until the oxygen content in the printing cabin reduces to oxygen content set threshold, the first valve and second valve are opened and fan is started, the fan sucks air in suction pipe into fan and blows into blowing pipe, and blows air in blowing pipe into printing cabin, while inert gas in the printing cabin is sucked into suction pipe and blown into blowing pipe, after the fan operates for a period of time, the fan, first valve and second valve are closed, and operation step S1 is repeated multiple times to complete the oxygen removal work of additive manufacturing equipment.

[0009] Further,

[0010] In step S1: the first pressure set threshold is controlled at 19-21kPa, and the second pressure set threshold is controlled at 2-3kPa;

[0011] In step S2: the oxygen content set threshold is 1000ppm.

[0012] Further, the time required for operating step S1 once is 20s.

[0013] Further, in step S2, the fan is closed after operating for 30s, and the first valve and second valve are closed.

[0014] Further, in step S2, the number of times of repeating operation step S1 required for reducing the oxygen content in the printing cabin to oxygen content set threshold is 2-3 times, and the number of times of repeating operation step S1 after closing the fan, first valve and second valve is 2-3 times.

[0015] Further, the first valve and second valve are both butterfly valves.

[0016] Further, one end of the air suction pipe is connected with one surface of the printing cabin through the air suction port and the other end is connected with the air inlet of the air blower.

[0017] Further, the air inlet valve is arranged on the lower surface of the printing cabin, the air outlet valve, the pressure sensor and the oxygen content sensor are arranged on the upper surface of the printing cabin, the air suction port is arranged on the left side surface of the printing cabin and the air blowing port is arranged on the right side surface of the printing cabin.

[0018] Further, the air inlet valve is an argon gas inlet valve, the inert gas cylinder is an argon gas cylinder and the air outlet valve is a mixed gas outlet valve.

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

[0020] In the oxygen removal method of the additive manufacturing equipment, in step S1, the inert gas is filled into the printing cabin and the pressure in the printing cabin is increased by closing the first valve, the second valve and the air outlet valve and opening the air inlet valve, so that the inert gas and air in the printing cabin can be fully mixed, then the mixed gas of the inert gas and air in the printing cabin is quickly discharged in a burst mode by closing the air inlet valve and opening the air outlet valve, and by repeating the operation of step S1 multiple times, most of the oxygen in the air in the printing cabin can be removed in a very short time. In step S2, the first valve and the second valve are opened and the air blower is started, the air blower sucks the air in the air suction pipe into the air blower and blows it into the air blowing pipe, and blows the air in the air blowing pipe into the printing cabin, at the same time, the inert gas in the printing cabin is sucked into the air suction pipe and blown into the air blowing pipe, after the air blower runs for a period of time, the air blower, the first valve and the second valve are closed, the replacement of the air in the air blower, the air suction pipe and the air blowing pipe with the inert gas in the printing cabin is completed, and by repeating the operation of step S1 multiple times, the oxygen in the air blown into the printing cabin is quickly removed. In the present application, before the air blower is started, the oxygen content in the printing cabin has been reduced to the oxygen content set threshold, so after the air blower is started, only the replacement of the air in the air blower, the air suction pipe and the air blowing pipe with the inert gas in the printing cabin is needed, there is no problem of the mixed gas of the inert gas and air in the printing cabin being sucked into the air suction pipe and the air blowing pipe, and there is no problem of the air in the printing cabin not being able to be smoothly discharged from the air outlet valve.

[0021] In summary, the method of the present application can remove the oxygen in the printing cabin, the air suction pipe, the air blower and the air blowing pipe in a very short time, can greatly reduce the oxygen removal time of the additive manufacturing equipment in the early stage, improve the oxygen removal efficiency, and thus can greatly improve the efficiency of the preparation work of the additive manufacturing equipment, so as to shorten the waiting time of 3D printing. BRIEF DESCRIPTION OF DRAWINGS

[0022] Figure 1 Structure diagram of the connection of the printing cabin, the suction pipe, the fan and the blowing pipe of the additive manufacturing equipment in the application.

[0023] The figure mark explanation: 1, printing cabin, 2, air inlet valve, 3, air outlet valve, 4, first valve, 5, suction pipe, 6, fan, 7, second valve, 8, blowing pipe, 9, inert gas cylinder, 10, pressure sensor, 11, oxygen content sensor, 12, suction port, 13, blowing port. DETAILED DESCRIPTION

[0024] The specific embodiments of the application will be further described in detail below with reference to the accompanying drawings. These embodiments are only used to illustrate the application, and are not limiting to the application.

[0025] In the description of the application, it should be noted that the terms "center", "longitudinal", "transverse", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, and are only for the convenience of describing the application and simplifying the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore cannot be understood as limiting to the application. In addition, the terms "first", "second" are only for the purpose of description, and cannot be understood as indicating or implying relative importance.

[0026] In the description of the application, it should be noted that unless otherwise explicitly specified and limited, the terms "mounting", "connecting", "connecting" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or integrally connected; it can be mechanically connected, or it can be electrically connected; it can be directly connected, or it can be indirectly connected through an intermediate medium; it can be the communication inside two elements. For those skilled in the art, the specific meaning of the above terms in the application can be understood according to the specific circumstances.

[0027] An oxygen removal method of an additive manufacturing equipment, the printing cabin 1 of the additive manufacturing equipment is provided with an air inlet valve 2 and an air outlet valve 3, the printing cabin 1 is connected with the air inlet of the fan 6 through the suction pipe 5 with the first valve 4, and is connected with the air outlet of the fan 6 through the blowing pipe 8 with the second valve 7, see Figure 1 The oxygen removal method comprises the following steps:

[0028] S1, close the first valve 4, the second valve 7 and the exhaust valve 3 and open the inlet valve 2, the inert gas in the inert gas cylinder 9 connected with the inlet valve 2 is filled into the printing cabin 1, and the pressure in the printing cabin 1 is detected in real time through the pressure sensor 10, when the pressure in the printing cabin 1 increases to the first pressure setting threshold, the inlet valve 2 is closed and the exhaust valve 3 is opened, the mixed gas of inert gas and air in the printing cabin 1 is discharged outward, when the pressure in the printing cabin 1 decreases to the second pressure setting threshold, the exhaust valve 3 is closed, and the oxygen content in the printing cabin 1 is detected through the oxygen content sensor 11;

[0029] S2, repeat the operation step S1 multiple times until the oxygen content in the printing cabin 1 decreases to the oxygen content setting threshold, open the first valve 4 and the second valve 7 and start the fan 6, the fan 6 sucks the air in the air suction pipe 5 into the fan 6 and blows it into the air blowing pipe 8, and blows the air in the air blowing pipe 8 into the printing cabin 1, at the same time, the inert gas in the printing cabin 1 is sucked into the air suction pipe 5 and blown into the air blowing pipe 8, after the fan 6 runs for a period of time, the fan 6, the first valve 4 and the second valve 7 are closed, and the operation step S1 is repeated multiple times to complete the oxygen removal work of the additive manufacturing equipment.

[0030] In this way, in step S1, first, the inert gas is filled into the printing cabin 1 by closing the first valve 4, the second valve 7 and the exhaust valve 3 and opening the inlet valve 2, and the pressure in the printing cabin 1 is increased, so that the inert gas and air in the printing cabin 1 can be fully mixed, then the mixed gas of inert gas and air in the printing cabin 1 is quickly discharged by explosion type by closing the inlet valve 2 and opening the exhaust valve 3, and by repeating the operation step S1 multiple times, most of the oxygen in the air in the printing cabin 1 can be removed in a very short time, and in step S2, by opening the first valve 4 and the second valve 7 and starting the fan 6, the fan 6 sucks the air in the air suction pipe 5 into the fan 6 and blows it into the air blowing pipe 8, and blows the air in the air blowing pipe 8 into the printing cabin 1, at the same time, the inert gas in the printing cabin 1 is sucked into the air suction pipe 5 and blown into the air blowing pipe 8, after the fan 6 runs for a period of time, the fan 6, the first valve 4 and the second valve 7 are closed, and the replacement of the air in the fan 6, the air suction pipe 5 and the air blowing pipe 8 with the inert gas in the printing cabin 1 is completed, and by repeating the operation step S1 multiple times, the oxygen in the air blown into the printing cabin 1 is quickly removed, in the present application, before the fan 6 is started, the oxygen content in the printing cabin 1 has been reduced to the oxygen content setting threshold, so after the fan 6 is started, only the replacement of the air in the fan 6, the air suction pipe 5 and the air blowing pipe 8 with the inert gas in the printing cabin 1 needs to be completed, there is no problem of the mixed gas of inert gas and air in the printing cabin 1 being sucked into the air suction pipe 5 and the air blowing pipe 8 as in the background art, and there is no problem that the air in the printing cabin 1 cannot be smoothly discharged from the exhaust valve 3.

[0031] wherein Figure 1The arrow at the inlet valve 2 indicates the direction of the inert gas, the arrow at the outlet valve 3 indicates the direction of the mixed gas of the inert gas and the air in the printing cabin 1, the arrow in the suction pipe 5 indicates the direction of the gas flow in the suction pipe 5, the arrow in the blowing pipe 8 indicates the direction of the gas flow in the blowing pipe 8, and the dotted line in the printing cabin 1 indicates the air field formed in the printing cabin 1 after the fan 6 is started.

[0032] In one embodiment,

[0033] In step S1, the first pressure setting threshold is controlled at 19-21 kPa, and the second pressure setting threshold is controlled at 2-3 kPa.

[0034] In step S2, the oxygen content setting threshold is 1000 ppm.

[0035] In one embodiment,

[0036] The time required for operating step S1 once is 20 s.

[0037] In step S2, the oxygen content in the printing cabin 1 is reduced to the oxygen content setting threshold, and the number of times of repeating the operation of step S1 is 2-3 times, the fan 6 is turned off after being operated for 30 s, and the first valve 4 and the second valve 7 are also turned off, and then the operation of step S12 is repeated for 3 times.

[0038] Thus, the total time required for the deoxygenation of the additive manufacturing equipment in the present application is between 110 s and 150 s, which is much shorter than the deoxygenation time of 30 min to 1 h or even several hours in the background art. The method of the present application can quickly remove the oxygen in the printing cabin 1, the suction pipe 5, the fan 6 and the blowing pipe 8.

[0039] In one embodiment,

[0040] The first valve 4 and the second valve 7 are both butterfly valves.

[0041] One end of the suction pipe 5 is connected to one surface of the printing cabin 1 through the suction port 12, and the other end is connected to the air inlet of the fan 6; one end of the blowing pipe 8 is connected to the other surface of the printing cabin 1 through the blowing port 13, and the other end is connected to the air outlet of the fan 6. In this way, the air in the fan 6, the suction pipe 5 and the blowing pipe 8 can be quickly replaced with the inert gas in the printing cabin 1.

[0042] The inlet valve 2 is arranged on the lower surface of the printing cabin 1, the outlet valve 3, the pressure sensor 10 and the oxygen content sensor 11 are arranged on the upper surface of the printing cabin 1, the suction port 12 is arranged on the left side surface of the printing cabin 1, and the blowing port 13 is arranged on the right side surface of the printing cabin 1.

[0043] The gas inlet valve 2 is an argon gas inlet valve 2, the inert gas cylinder 9 is an argon cylinder, and the gas outlet valve 3 is a mixed gas outlet valve 3.

[0044] In conclusion, the method of the present application can remove the oxygen in the printing cabin 1, the air suction pipe 5, the fan 6 and the air blowing pipe 8 in a very short time, can greatly reduce the oxygen removal time of the additive manufacturing equipment in the early stage, improve the oxygen removal efficiency, and further greatly improve the efficiency of the additive manufacturing equipment in the early stage, thereby shortening the waiting time of 3D printing.

[0045] The above only describes the preferred embodiments of the present application, and it should be pointed out that for ordinary skilled persons in the art, several improvements and replacements can be made without departing from the technical principles of the present application, and these improvements and replacements should also be considered as the protection scope of the present application.

Claims

1. A method for removing oxygen from an additive manufacturing device, the additive manufacturing device having a printing cabin (1) provided with an air inlet valve (2) and an air outlet valve (3), the printing cabin (1) being connected to an air inlet of a fan (6) through a suction pipe (5) provided with a first valve (4) and connected to an air outlet of the fan (6) through a blowing pipe (8) provided with a second valve (7), characterized in that, The oxygen removal method comprises the following steps: S1, close the first valve (4), the second valve (7) and the exhaust valve (3) and open the inlet valve (2), the inert gas in the inert gas cylinder (9) connected with the inlet valve (2) is filled into the printing cabin (1), and the pressure in the printing cabin (1) is detected in real time through the pressure sensor (10), when the pressure in the printing cabin (1) increases to the first pressure setting threshold, the inlet valve (2) is closed and the exhaust valve (3) is opened, the mixed gas of inert gas and air in the printing cabin (1) is discharged outward, when the pressure in the printing cabin (1) decreases to the second pressure setting threshold, the exhaust valve (3) is closed, and the oxygen content in the printing cabin (1) is detected by the oxygen content sensor (11); S2, repeat the operation step S1 multiple times until the oxygen content in the printing cabin (1) decreases to the oxygen content setting threshold, open the first valve (4) and the second valve (7) and start the fan (6), the fan (6) sucks the air in the air suction pipe (5) into the fan (6) and blows it into the air blowing pipe (8), and blows the air in the air blowing pipe (8) into the printing cabin (1), at the same time, the inert gas in the printing cabin (1) is sucked into the air suction pipe (5) and blown into the air blowing pipe (8), after the fan (6) runs for a period of time, the fan (6), the first valve (4) and the second valve (7) are closed, and the operation step S1 is repeated multiple times to complete the oxygen removal of the additive manufacturing equipment.

2. The oxygen removal method of the additive manufacturing equipment according to claim 1, wherein, In step S1, the first pressure setting threshold is controlled at 19-21kPa, and the second pressure setting threshold is controlled at 2-3kPa; In step S2, the oxygen content setting threshold is 1000ppm.

3. A method of oxygen removal from an additive manufacturing apparatus according to claim 1, characterized in that: The time required for operating step S1 once is 20s.

4. The method of oxygen removal of an additive manufacturing apparatus according to claim 1, wherein: In step S2, the fan (6) is closed after running for 30s, and the first valve (4) and the second valve (7) are closed.

5. The method of oxygen removal of an additive manufacturing apparatus according to claim 1, wherein: In step S2, the number of times of repeating operation step S1 required for reducing the oxygen content in the printing cabin (1) to the oxygen content setting threshold is 2-3 times, and after the fan (6), the first valve (4) and the second valve (7) are closed, the number of times of repeating operation step S1 is 2-3 times.

6. The method of oxygen removal of an additive manufacturing apparatus according to claim 1, wherein: The first valve (4) and the second valve (7) are both butterfly valves.

7. The method of oxygen removal of an additive manufacturing apparatus according to claim 1, wherein: One end of the air suction pipe (5) is connected with one surface of the printing cabin (1) through the air suction port (12), and the other end is connected with the air inlet of the fan (6); one end of the air blowing pipe (8) is connected with the other surface of the printing cabin (1) through the air blowing port (13), and the other end is connected with the air outlet of the fan (6).

8. A method of oxygen removal from an additive manufacturing apparatus according to claim 7, wherein: The inlet valve (2) is arranged on the lower surface of the printing cabin (1), the exhaust valve (3), the pressure sensor (10) and the oxygen content sensor (11) are arranged on the upper surface of the printing cabin (1), the air suction port (12) is arranged on the left side surface of the printing cabin (1), and the air blowing port (13) is arranged on the right side surface of the printing cabin (1).

9. The method of oxygen removal of an additive manufacturing apparatus according to claim 1, wherein: The gas inlet valve (2) is an argon gas inlet valve (2), the inert gas cylinder (9) is an argon cylinder, and the gas outlet valve (3) is a mixed gas outlet valve (3).

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