CN110976871A

CN110976871A - Powder recycling circulation system of selective laser sintering equipment and control method thereof

Info

Publication number: CN110976871A
Application number: CN201911380873.9A
Authority: CN
Inventors: 杨琢; 周智阳; 陈亮
Original assignee: Hunan Farsoon High Tech Co Ltd
Current assignee: Hunan Farsoon High Tech Co Ltd
Priority date: 2019-12-27
Filing date: 2019-12-27
Publication date: 2020-04-10

Abstract

The invention relates to a powder recycling circulation system of selective laser sintering equipment and a control method thereof. The powder recycling circulating system of the selective laser sintering equipment comprises a power device, a separating tank, a storage tank, a conveying tank and a first recycling tank, wherein the discharge end of the separating tank is communicated with the feed end of the storage tank; the discharge end of the material storage tank is communicated with the feed end of the conveying tank, and the exhaust end of the conveying tank is communicated with the feed end of the separation tank; the discharge end of the first recovery tank is communicated with the feed end of the separation tank; the exhaust port of the power device is communicated with the discharge end of the storage tank and the discharge end of the first recovery tank, and the exhaust port is communicated with the exhaust end of the separation tank. The powder recycling circulation system of the selective laser sintering equipment and the control method thereof provided by the invention have the advantages that under the action of the power device, the powder circularly moves among the storage tank, the conveying tank and the separating tank and circularly moves among the first recycling tank and the separating tank, so that the powder recycling operation is simple, the labor intensity is low and the safety is good.

Description

Powder recycling circulation system of selective laser sintering equipment and control method thereof

Technical Field

The invention relates to the technical field of additive manufacturing, in particular to a powder recycling and circulating system of selective laser sintering equipment and a control method thereof.

Background

Additive Manufacturing (AM) is an advanced Manufacturing technology with the advantages of digital Manufacturing, high flexibility and adaptability, direct CAD model driving, rapidness, rich and diverse material types, and the like. Among them, Selective Laser Melting (SLM) is one of the additive manufacturing technologies that have been rapidly developed in recent years, and it uses a powder material as a raw material, and performs layer-by-layer scanning on a cross section of a three-dimensional entity by using Laser to complete prototype manufacturing, and is not limited by the complexity of the shape, does not need any tooling die, and has a wide application range.

The basic processes of the selective laser melting process include powder feeding and powder recovery. At present, the powder supply and the powder recovery generally adopt a manual operation mode, and the tank body for supplying and recovering the powder is manually disassembled and replaced by an operator in the sintering process.

However, the manual operation mode of the operator is complex in operation, the operator needs to pay attention to the use state of the powder in real time, the emptied supply tank and the full recovery tank are replaced in time, and meanwhile, great potential safety hazards exist, such as powder loss and personal safety in the process that the operator lifts the tank body.

Disclosure of Invention

Therefore, it is necessary to provide a powder recycling circulation system of a selective laser sintering device and a control method thereof, which are simple to operate, low in labor intensity and safe, aiming at the problems of complicated operation, high labor intensity and high potential safety hazard caused by the fact that the powder supply and the powder recycling in the existing selective laser melting process are both manually operated.

A powder recovery circulation system of selective laser sintering equipment comprises a power device, a separation tank, a storage tank, a conveying tank of the selective laser sintering equipment and a first recovery tank communicated with a working cavity of the selective laser sintering equipment;

the discharge end of the knockout drum is in operable communication with the feed end of the storage tank;

the discharge end of the storage tank is in operable communication with the feed end of the transfer tank, and the discharge end of the transfer tank is in operable communication with the feed end of the separation tank;

the discharge end of the first recovery tank is in operable communication with the feed end of the separation tank;

the power device comprises an air suction opening and an air exhaust opening, the air exhaust opening is communicated with the discharge end of the storage tank and the discharge end of the first recovery tank in an operable mode, and the air suction opening is communicated with the exhaust end of the separation tank.

In one embodiment, the powder recycling system further comprises a powder post-processing platform and a second recycling tank;

the powder post-processing platform still has the bin outlet, the bin outlet with the second retrieves the feed end intercommunication of jar, the bin outlet of jar is retrieved to the second operatively with the feed end intercommunication of knockout drum, power device the gas vent operatively with the bin outlet intercommunication of jar is retrieved to the second.

In one embodiment, the powder aftertreatment platform has an air inlet and a powder suction port separate from the discharge port, the powder suction port being in operable communication with the feed end of the knockout drum, and the exhaust port of the power plant being in operable communication with the air inlet.

In one embodiment, the powder recycling system is a closed powder recycling system, and the powder recycling system is filled with an inert gas.

In one embodiment, the powder recovery circulation system further comprises an aerobic detection sensor for detecting the oxygen content within the powder recovery circulation system.

In one embodiment, the discharge end of the storage tank and the discharge end of the first recovery tank are both provided with pulse type stop valves, and the pulse type stop valves are used for adjusting the discharge amount and the discharge speed of the discharge end of the storage tank and the discharge end of the first recovery tank.

In one embodiment, the powder recycling system further comprises a vibrating screen disposed between the separation tank and the storage tank, wherein the vibrating screen is used for screening and discharging the powder discharged from the discharge end of the separation tank to the storage tank.

In one embodiment, the selective laser sintering apparatus comprises a plurality of selective laser sintering apparatuses, wherein the feed end of the conveying tank of each selective laser sintering apparatus is operatively communicated with the discharge end of the storage tank, the exhaust end of the conveying tank is operatively communicated with the feed end of the separation tank, and the discharge end of the first recovery tank is operatively communicated with the feed end of the separation tank.

A control method of the powder recycling circulation system of the selective laser sintering equipment comprises the following steps:

detecting the residual amount of powder in the conveying tank, and controlling the power device to start, the discharge end of the material storage tank to open and the exhaust end of the conveying tank to open when the residual amount of powder in the conveying tank is lower than a first preset residual amount;

detecting the powder allowance in the storage tank, and controlling the power device to stop, the discharge end of the storage tank to be closed and the exhaust end of the conveying tank to be closed when the powder allowance in the storage tank is lower than a second preset allowance;

detecting the residual amount of powder in the first recovery tank, controlling the power device to be started and the discharge end of the first recovery tank to be opened when the residual amount of the powder in the first recovery tank is higher than a third preset residual amount, and controlling the power device to be stopped and the discharge end of the first recovery tank to be closed when the residual amount of the powder in the first recovery tank is lower than a fourth preset residual amount;

detect powder surplus in the knockout drum, work as when powder surplus in the knockout drum is higher than the fifth allowance of predetermineeing, control the discharge end of knockout drum is opened and is reached the feed end of storage tank is opened, works as powder surplus in the knockout drum is less than the sixth allowance of predetermineeing or when powder surplus in the storage tank is higher than the seventh allowance of predetermineeing, control the discharge end of knockout drum is closed and the feed end of storage tank is closed.

In one embodiment, the powder recycling system is a closed powder recycling system, inert gas is filled in the powder recycling system, and the powder recycling system further comprises an oxygen detection sensor for detecting the oxygen content in the powder recycling system;

the control method of the powder recovery circulation system further comprises the steps of:

controlling the aerobic detection sensor to detect the oxygen content in the powder recovery circulation system;

when the oxygen content detected by the aerobic detection sensor is higher than a preset oxygen content value, adjusting the content of inert gas in the powder recovery circulation system so as to enable the oxygen content in the powder recovery circulation system to be lower than the preset oxygen content value.

According to the powder recycling and circulating system of the selective laser sintering equipment and the control method thereof, under the action of the power device, the powder circularly moves among the storage tank, the conveying tank and the separating tank and circularly moves among the first recycling tank and the separating tank, so that the powder can be recycled, and the powder recycling and circulating system is simple to operate, low in labor intensity and good in safety.

Drawings

Fig. 1 is a schematic structural diagram of a powder recycling system of a selective laser sintering apparatus according to an embodiment of the present invention.

Detailed Description

To facilitate an understanding of the invention, the invention will now be described more fully with reference to the accompanying drawings. Preferred embodiments of the present invention are shown in the drawings. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items.

When an element is referred to as being "on" another element, it can be directly on the other element or intervening elements may also be present, unless otherwise specified. It will also be understood that when an element is referred to as being "between" two elements, it can be the only one between the two elements, or one or more intervening elements may also be present.

Where the terms "comprising," "having," and "including" are used herein, another element may be added unless an explicit limitation is used, such as "only," "consisting of … …," etc. Unless mentioned to the contrary, terms in the singular may include the plural and are not to be construed as being one in number.

It will also be understood that when interpreting elements, although not explicitly described, the elements are to be interpreted as including a range of errors which are within the acceptable range of deviation of the particular values as determined by those skilled in the art. For example, "about," "approximately," or "substantially" may mean within one or more standard deviations, without limitation.

Furthermore, the drawings are not 1: 1, and the relative dimensions of the various elements in the figures are drawn for illustration only and not necessarily to true scale.

Fig. 1 is a schematic structural view showing a powder recycling system of a selective laser sintering apparatus according to an embodiment of the present invention. For the purpose of illustration, the drawings show only the structures associated with embodiments of the invention.

Referring to the drawings, a powder recycling system 100 of a selective laser sintering apparatus according to an embodiment of the present invention includes a power device 10, a separation tank 20, a storage tank 30, a delivery tank 40 of the selective laser sintering apparatus, and a first recycling tank 50 communicated with a working chamber of the selective laser sintering apparatus.

The discharge end of the knockout drum 20 is in operable communication with the feed end of the holding tank 30.

The discharge end of the holding tank 30 is in operable communication with the feed end of the transfer tank 40, and the discharge end of the transfer tank 40 is in operable communication with the feed end of the separation tank 20. When the powder residual amount of the conveying tank 40 is insufficient, the powder in the storage tank 30 is conveyed into the conveying tank 40, so that the powder can be recycled. Specifically, the conveying tank 40 is provided therein with a separating device for separating gas and powder, and more specifically, the separating device is a cyclone separator which can preliminarily filter out large-particle powder, discharge the large-particle powder into the conveying tank 40, and convey the small-particle powder into the separating tank 20 through the exhaust end for filtering.

It should be appreciated that the discharge end of the delivery tank 40 is connected to the powder supply mechanism of the selective laser sintering apparatus to ensure timely delivery of the selective laser sintering apparatus.

The discharge end of the first recovery tank 50 is in operable communication with the feed end of the separation tank 20. The first recovery tank 50 is communicated with the working cavity of the selective laser sintering equipment and is used for recovering residual powder in the working cavity.

The power plant 10 includes a suction port 11 and an exhaust port 12, the exhaust port 12 being in operable communication with the discharge end of the storage tank 30 and the discharge end of the first recovery tank 50, the suction port 11 being in operable communication with the exhaust end of the separation tank 20. Under the action of the power device 10, the powder discharged from the discharge end of the storage tank 30 can be conveyed to the conveying tank 40 under positive pressure and then conveyed to the separation tank 20 through the conveying tank 40, the powder discharged from the discharge end of the first recovery tank 50 can also be conveyed to the separation tank 20 under positive pressure, and the clean gas discharged from the exhaust end of the separation tank 20 is absorbed and reused by the extraction opening 11 of the power device 10. It should be understood that the pressure of the exhaust opening 11 and the pressure of the exhaust opening 12 of the power device 10 are adjustable, and preferably, the power device 10 can generate larger positive pressure pushing capacity at the exhaust opening 12 and smaller negative pressure adsorption capacity at the exhaust opening 11, so that the powder can be conveyed at a higher speed under positive pressure, and the recovery efficiency of the powder recovery circulation system 100 is improved.

It should be appreciated that the separator tank 20 is provided with a filter inside, which filters the powder entering from the feed end of the separator tank 20 to ensure that clean gas is exhausted from the exhaust end of the separator tank 20 to the extraction opening 11 of the power plant 10 for reuse.

It should also be understood that those skilled in the art will know that the communication between the communicating parts should be performed using pipes.

Thus, the powder recycling system 100 of the selective laser sintering apparatus of the present invention can circulate the powder among the storage tank 30, the transportation tank 40 and the separation tank 20 and between the first recycling tank 50 and the separation tank 20 under the action of the power device 10, so that the powder can be recycled, and thus, the powder recycling operation is simple, the labor intensity is low, and the safety is good. In addition, the powder recycling system 100 of the present invention only uses one power device 10, so that the requirement of conveying and recycling multiple pipelines can be realized, and the cost of powder recycling is greatly saved.

In some embodiments, the powder recovery circulation system 100 includes a plurality of high level gauges 60, a plurality of low level gauges 65, and a plurality of shut-off valves 70. Specifically, a high level gauge 60 and a low level gauge 65 are arranged on the separation tank 20, a stop valve 70 is arranged at the discharge end of the separation tank 20, a high level gauge 60 and a low level gauge 65 are arranged on the storage tank 30, a stop valve 70 is arranged at the discharge end of the storage tank 30, a stop valve 70 is also arranged on a pipeline for communicating the exhaust port 12 of the power device 10 with the discharge end of the storage tank 30, a high level gauge 60 and a low level gauge 65 are arranged on the first recovery tank 50, a stop valve 70 is arranged at the discharge end of the first recovery tank 50, and a stop valve 70 is also arranged on a pipeline for communicating the exhaust port 12 of the power device 10 with the discharge end of the first recovery tank 50. In this way, whether the powder remaining in the tank interior reaches a preset high level or a preset low level can be measured by the high level gauge 60 and the low level gauge 65, and the communication between the respective components can be operatively switched on or off by opening or closing the shut-off valve 70.

Further, the stop valves 70 disposed at the discharge end of the storage tank 30 and the discharge end of the first recovery tank 50 are both pulse stop valves, and the pulse stop valves are used for adjusting the discharge amount and the discharge speed of the discharge end of the storage tank 30 and the discharge end of the first recovery tank 50. Because the discharge end lower extreme of storage tank 30 and the discharge end lower extreme of first recovery tank 50 are located the intersection of three pipelines, so in case powder piles up, then cause powder recovery circulation system 100 trouble easily, damage even, so set up pulsed stop valve and can effectively control the stock discharge and arrange material speed, avoid the trouble to take place.

In an embodiment of the present invention, the powder recycling system 100 may include a controller electrically connected to the plurality of high level gauges 60, the plurality of low level gauges 65, and the plurality of shut-off valves 70, respectively, to control the communication relationship among the components. Therefore, the automatic operation of the powder recycling circulating system 100 can be realized, and the complicated flow of manual operation, personal safety and environmental safety hidden dangers are further avoided.

In some embodiments, the powder recovery circulation system 100 further includes a powder post-processing platform 75 and a second recovery tank 80, the powder post-processing platform 75 having a discharge opening in communication with a feed end of the second recovery tank 80, a discharge end of the second recovery tank 80 in operable communication with a feed end of the separation tank 20, and the vent 12 of the power plant 10 in operable communication with a discharge end of the second recovery tank 80. In this way, the powder of the powder post-processing platform 75 can be recovered by the second recovery tank 80, and the recovery capability of the powder recovery circulation system 100 is further improved.

Further, the powder post-processing platform 75 also has an air inlet 751 and a powder suction port 752 separate from the discharge port, the powder suction port 752 being operatively in communication with the feed end of the separation tank 20, and the exhaust port 12 of the power plant 20 being operatively in communication with the air inlet 751. When the powder post-processing platform 75 is used for powder post-processing, most of the powder can be recovered from the discharge opening to the second recovery tank 80, and a small amount of powder remaining on the surface of the workpiece can be adsorbed into the separation tank 20 by the power device 20 through the powder adsorption opening 752. Thus, the recovery amount of the powder can be increased.

In the existing powder post-treatment, a large amount of powder left after sintering is treated by an external negative pressure adsorption device, although the powder transfer can be conveniently completed by a negative pressure adsorption mode, the working principle of the negative pressure adsorption mode has inherent defects, for example, the negative pressure adsorption mode can only be suitable for an open-loop or semi-open-loop working environment, in the 3D printing industry, a lot of important materials, such as titanium alloy, pure titanium, aluminum alloy and the like, need an extremely low oxygen content environment to ensure the safety of equipment and personnel in the conveying process, and the negative pressure adsorption mode can not ensure that the oxygen content in the conveying system reaches the use requirements of the high-activity metal materials. In addition, the small negative pressure source can only adapt to powder conveying at a single place, and powder conveying at a plurality of places needs a plurality of negative pressure sources to be connected in parallel, so that the cost is obviously increased.

In the embodiment of the present invention, the powder recycling system 100 is a closed powder recycling system, and the powder recycling system 100 is filled with an inert gas. Since the power device 20 realizes the recycling of the gas, the powder recycling system 100 can be closed, and thus, the inert gas filled in the powder recycling system 100 can be more suitable for the recycling requirement of various kinds of powder including various active metals.

Further, the powder recovery circulation system 100 includes an exhaust valve provided on the exhaust end side of the separation tank 20 and a pressure sensor 85 for detecting the pressure in the powder recovery circulation system 100. Specifically, the pressure sensor 85 may be provided on the separation tank 20, and the exhaust valve is provided at the exhaust end of the separation tank 20 to exclude interference of the powder. The pressure sensor 85 and the exhaust valve are used to monitor and exhaust the excessive pressure inside the powder recycling system 100, so as to ensure the normal operation of the powder recycling system 100 and prevent the powder recycling system 100 from being damaged due to overpressure.

In some embodiments, the powder recovery cycle system 100 further comprises an aerobic detection sensor 90, the aerobic detection sensor 90 being configured to detect the oxygen content within the powder recovery cycle system 100. Thus, it is ensured that the oxygen content in the powder recycling system 100 exceeds a predetermined value, which affects the chemical properties of the powder. An oxygen detection sensor 90 is provided at the discharge end of the separation tank 20 to exclude interference of the powder.

In some embodiments, the powder recycling system 100 further comprises an inert gas supplementing device for supplementing an inert gas into the powder recycling system 100. When the oxygen detection sensor 90 detects that the oxygen content in the powder recycling system 100 exceeds a preset value, the inert gas can be supplemented using an inert gas supplementing device. In addition, due to the positive pressure characteristic of the power device 10, when the exhaust valve works, the fluctuation of oxygen content caused by the fact that external air enters the powder recovery circulation system 100 can be prevented, so that the powder recovery circulation system 100 can reach any required oxygen content only by maintaining a small amount of inert gas supplement, and compared with a traditional negative pressure adsorption conveying system, the consumption of the inert gas is greatly saved.

In some embodiments, the powder recovery circulation system 100 further comprises a vibrating screen 95, the vibrating screen 95 being disposed between the separation tank 20 and the storage tank 30, the vibrating screen 95 being used to screen and discharge the powder discharged from the discharge end of the separation tank 20 to the storage tank 30. Currently, the materials that can be successfully processed by selective laser sintering include paraffin, polymer, metal, ceramic powder and their composite materials, especially metal materials, in which after each sintering, the remaining metal powder particle ash generates metal spheroidization products, splash oxidation products, and residues. At this time, the residual powder after sintering must be cleaned of large-particle waste by the vibrating screen 95 so that the residual powder can be recycled.

In an embodiment of the present invention, the selective laser sintering apparatus includes a plurality of selective laser sintering apparatuses, a discharge end of the storage tank 30 of each selective laser sintering apparatus is operatively communicated with a feed end of the transfer tank 40, a discharge end of the transfer tank 40 is operatively communicated with a feed end of the separation tank 20, and a discharge end of the first recovery tank 50 is operatively communicated with a feed end of the separation tank 20. Therefore, the powder recycling system 100 can recycle the powder in the selective laser sintering equipment, and the recycling efficiency is improved.

Based on the same inventive concept, the present invention also provides a method for controlling the powder recycling system 100 of the selective laser sintering apparatus, comprising the steps of:

s110: detecting the powder allowance in the conveying tank 40, and controlling the power device 10 to be started, the discharge end of the storage tank 30 to be opened and the exhaust end of the conveying tank 40 to be opened when the powder allowance of the conveying tank 40 is lower than a first preset allowance;

wherein, selective laser sintering equipment's powder recovery circulation system 100 can include the controller, be provided with a low level charge level indicator 65 that is connected with the controller electricity on the transport jar 40, low level charge level indicator 65 setting value is first preset allowance, the discharge end department of storage tank 30 is equipped with a pulsed stop valve, the exhaust end department of transport jar 40 is equipped with a stop valve, so, when low level charge level indicator 65 detected that the powder surplus in transport jar 40 is less than first preset allowance, the controller received this signal, then the pulsed stop valve of the discharge end department of control storage tank 30 is opened, the stop valve of the exhaust end department of transport jar 40 is opened.

Further, the pulse type stop valve can be controlled by the controller to adjust the discharge amount and the discharge speed of the discharge end of the storage tank 30.

S120: and detecting the residual amount of the powder in the storage tank 30, and controlling the power device 20 to stop, the discharge end of the storage tank 30 to be closed and the exhaust end of the conveying tank 40 to be closed when the residual amount of the powder in the storage tank 30 is lower than a second preset residual amount.

Wherein, be provided with a low level charge level indicator 65 that is connected with the controller electricity on the storage tank 30, this low level charge level indicator 65 setting value is the second and predetermines the surplus, so, when low level charge level indicator 65 detected that the powder surplus in the storage tank 30 is less than the second and predetermines the surplus, the controller received this signal, then the pulsed stop valve of the discharge end department of control storage tank 30 is closed, and the stop valve of the exhaust end department of transport tank 40 is closed.

S130: detecting the residual amount of the powder in the first recovery tank 50, controlling the power device 10 to start and the discharge end of the first recovery tank 50 to be opened when the residual amount of the powder in the first recovery tank 50 is higher than a third preset residual amount, and controlling the power device 10 to stop and the discharge end of the first recovery tank 50 to be closed when the residual amount of the powder in the first recovery tank 50 is lower than a fourth preset residual amount;

wherein, be equipped with a high-order charge level indicator 60 and a low level charge level indicator 65 that are connected with the controller electricity on the first recovery jar 50, the setting value of this high-order charge level indicator 60 is the third and predetermines the surplus, and the setting value of low level charge level indicator 65 is the fourth and predetermines the surplus, and the discharge end department of first recovery jar 50 is equipped with a pulsed stop valve that is connected with the controller electricity. Thus, when the high level indicator 60 detects that the remaining amount of powder in the first recovery tank 50 is higher than the third preset remaining amount, the controller receives the signal and controls the pulse type stop valve at the discharge end of the first recovery tank 50 to be opened, and when the low level indicator 65 detects that the remaining amount of powder in the first recovery tank 50 is lower than the fourth preset remaining amount, the controller receives the signal and controls the pulse type stop valve at the discharge end of the first recovery tank 50 to be closed.

And S140, detecting the residual amount of the powder in the separation tank 20, controlling the discharge end of the separation tank 20 to be opened and the feed end of the storage tank 30 to be opened when the residual amount of the powder in the separation tank 20 is higher than a fifth preset residual amount, and controlling the discharge end of the separation tank 20 to be closed and the feed end of the storage tank 30 to be closed when the residual amount of the powder in the separation tank 20 is lower than a sixth preset residual amount or the residual amount of the powder in the storage tank 30 is higher than a seventh preset residual amount.

Wherein, be equipped with a high-order charge level indicator 60 and a low level charge level indicator 65 that are connected with the controller electricity on knockout drum 20, the setting value of this high-order charge level indicator 60 is the fifth preset allowance, the setting value of low level charge level indicator 65 is the sixth preset allowance, still be equipped with a high-order charge level indicator 60 that is connected with the controller electricity on the storage tank 30, the setting value of this high-order charge level indicator 60 is the seventh preset allowance, the discharge end department of knockout drum 20 or the feed end department of storage tank 30 are equipped with a stop valve 70 that is connected with the controller electricity. Thus, when the high level gauge 60 of the separation tank 20 detects that the powder residual amount in the separation tank 20 is higher than the fifth preset residual amount, the controller receives the signal to control the stop valve 70 at the discharge end of the separation tank 20 to be opened, and when the low level gauge 65 of the separation tank 20 detects that the powder residual amount in the separation tank 20 is lower than the sixth preset residual amount or when the high level gauge 60 of the storage tank 30 detects that the powder residual amount in the storage tank 30 is higher than the seventh preset residual amount, the controller receives the signal to control the stop valve 70 at the discharge end of the separation tank 20 or the feed end of the storage tank 30 to be closed.

It should be understood that the powder from the knockout drum 20 can be discharged into the holding tank 30 by gravity, so that transportation is achieved without the use of positive pressure from the power plant 10.

Further, when the remaining amount of the powder in the separation tank 20 is higher than the fifth predetermined remaining amount, the vibrating screen 95 may be controlled to be activated while the discharge end of the separation tank 20 is controlled to be opened and the feed end of the storage tank 30 is controlled to be opened, so as to sieve the powder. When the powder residual in the separating tank 20 is lower than the sixth preset residual or the powder residual in the storage tank 30 is higher than the seventh preset residual, the vibrating screen 95 is controlled to stop while the discharge end of the separating tank 20 and the feed end of the storage tank 30 are controlled to be closed.

In some embodiments, the method for controlling the powder recycling system 100 of the selective laser sintering apparatus further includes the steps of:

s150: detecting the residual amount of the powder in the second recovery tank 80, controlling the power device 10 to start and the discharge end of the second recovery tank 80 to open when the residual amount of the powder in the second recovery tank 80 is higher than the eighth preset residual amount, and controlling the power device 10 to stop and the discharge end of the second recovery tank 80 to close when the residual amount of the powder in the second recovery tank 80 is lower than the ninth preset residual amount.

Wherein, be equipped with a high-order charge level indicator 60 and a low level charge level indicator 65 that are connected with the controller electricity on the second recovery jar 80, this high-order charge level indicator 60's setting value is the eighth allowance of predetermineeing, and the setting value of low level charge level indicator 65 is the ninth allowance of predetermineeing, and the discharge end department of second recovery jar 80 is equipped with a pulsed stop valve that is connected with the controller electricity. So, when high-order charge level indicator 60 detects that the surplus of powder in second recovery tank 80 is higher than the eighth preset margin, the controller receives this signal, then the pulsed stop valve of the discharge end department of control second recovery tank 80 opens, when low-order charge level indicator 65 detects that the surplus of powder in second recovery tank 80 is less than the ninth preset margin, the controller receives this signal, then the pulsed stop valve of the discharge end department of control second recovery tank 80 closes.

s160: the control power device 20 is started, the air inlet 751 of the powder post-processing platform 75 is opened, and the powder suction port 752 is opened.

Wherein, a stop valve 70 electrically connected with the controller can be arranged at the air inlet 751 and the powder suction port 752 of the powder post-processing platform 75, so that when the powder suction function is started, the stop valves 70 at the air inlet 751 and the powder suction port 752 of the powder post-processing platform 75 can be opened to finish the powder suction.

s170: the oxygen content in the powder recycling circulating system 100 is detected by controlling the oxygen detection sensor 90, and when the oxygen content detected by the oxygen detection sensor 90 is higher than a preset oxygen content value, the content of the inert gas in the powder recycling circulating system 100 is adjusted so that the oxygen content in the powder recycling circulating system 100 is lower than the preset oxygen content value.

The powder recycling system 100 further includes an inert gas supply device and a stop valve 70 located at an exhaust port of the inert gas supply device and electrically connected to the controller, and the oxygen detection sensor 90 is electrically connected to the controller, so that when the oxygen content detected by the oxygen detection sensor 90 is higher than a predetermined oxygen content value, the stop valve 70 of the inert gas supply device is controlled to be opened, and when the oxygen content detected by the oxygen detection sensor 90 is lower than the predetermined oxygen content value, the stop valve 70 of the inert gas supply device is controlled to be closed.

It should be understood that when the powder recovery circulation system 100 of the selective laser sintering apparatus is in standby, all the shut-off valves 70 are in a closed state, the power unit 20 is stopped, and the powder state is monitored by the level gauges on the respective tanks to determine whether to start the transportation or recovery function.

It should also be understood that the present invention is not limited to the sequential order of the above steps.

The powder recycling circulation system 100 of the selective laser sintering equipment and the control method thereof provided by the embodiment of the invention have the following beneficial effects:

under the action of the power device 10, the powder is circularly moved among the storage tank 30, the conveying tank 40 and the separating tank 20 and between the first recovery tank 50 and the separating tank 20, so that the powder can be recovered, and the powder recovery and circulation system 100 has the advantages of simple operation, low labor intensity and good safety.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.

Claims

1. A powder recovery circulation system of selective laser sintering equipment is characterized by comprising a power device, a separation tank, a storage tank, a conveying tank of the selective laser sintering equipment and a first recovery tank communicated with a working cavity of the selective laser sintering equipment;

2. The powder recycling system of the selective laser sintering apparatus of claim 1, further comprising a powder post-processing platform and a second recycling tank;

3. The powder recycling system of a selective laser sintering apparatus of claim 2, wherein the powder post-processing platform has a gas inlet and a powder suction port separate from the discharge port, the powder suction port being in operable communication with the feed end of the knockout drum, the gas outlet of the power plant being in operable communication with the gas inlet.

4. The powder recycling system of selective laser sintering equipment of claim 1, wherein the powder recycling system is a closed powder recycling system, and the powder recycling system is filled with inert gas.

5. The powder recycling system of a selective laser sintering apparatus of claim 4, further comprising an aerobic detection sensor for detecting oxygen content within the powder recycling system.

6. The powder recycling system of a selective laser sintering apparatus of claim 1, wherein the discharge end of the storage tank and the discharge end of the first recycling tank are provided with pulse type stop valves for adjusting the discharge amount and the discharge speed of the discharge end of the storage tank and the discharge end of the first recycling tank.

7. The powder recycling system of a selective laser sintering apparatus of claim 1, further comprising a vibrating screen disposed between the separation tank and the storage tank, the vibrating screen being configured to screen and discharge the powder discharged from the discharge end of the separation tank to the storage tank.

8. The powder recycling system of a selective laser sintering apparatus of claim 1, wherein the selective laser sintering apparatus comprises a plurality of selective laser sintering apparatuses, each selective laser sintering apparatus having a feed end of the transport tank in operable communication with a discharge end of the storage tank, a discharge end of the transport tank in operable communication with a feed end of the knockout tank, and a discharge end of the first recovery tank in operable communication with a feed end of the knockout tank.

9. A method for controlling a powder recycling system of a selective laser sintering apparatus according to any one of claims 1 to 8, comprising the steps of:

10. The method for controlling a powder recycling system of a selective laser sintering apparatus according to claim 9, wherein the powder recycling system is a closed powder recycling system, the powder recycling system is filled with an inert gas, and the powder recycling system further includes an oxygen detection sensor for detecting an oxygen content in the powder recycling system;