Circulating powder supply system of SLM printing equipment

Abstract

The utility model discloses a circulating powder supply system of SLM printing equipment. A lower connector of a residual powder transfer powder tank is connected with a gas circuit powder conveying pipeline; an outlet of the blower is connected to an inlet of the gas circuit powder conveying pipeline; the cyclone separator is connected with an outlet of the gas circuit powder conveying pipeline; a powder outlet of the cyclone separator is connected with an inlet of the powder drying chamber, the powder drying chamber is connected with an inlet of the ultrasonic screening device, and the ultrasonic screening device is connected with the main powder storage tank. An output port in one side of the air bag is connected with an inlet of the arch breaking pipeline, an outlet of the arch breaking pipeline is internally connected with the main powder storage tank, the material supplementing tank, the top powder storage tank and the transfer powder tank, the top powder storage tank is arranged at the top of the SLM printing equipment, and an outlet of the top powder storage tank is connected to an inlet in the top of the SLM printing equipment; the material supplementing tank is connected to the gas circuit powder conveying pipeline; and the SLM printing unit is arranged on the gas circuit powder conveying pipeline. The problem that in the prior art, the efficiency is low due to the fact that powder is manually added or carried to complete the powder supply link of the printing equipment is solved.

Description

Technical Field

[0001] The present application belongs to the field of additive manufacturing technology, and specifically relates to a circulating powder supply system for SLM printing equipment. Background Art

[0002] Additive manufacturing is an advanced manufacturing technology that is data-driven and uses materials to form solid parts layer by layer. Compared with traditional subtractive manufacturing, this technology can form lightweight, complex and multi-material gradient parts, with a short process flow, less material waste, no need for molds, and supports personalized and customized processing. With the development of modern science, additive manufacturing technology has been applied to many fields, such as repairing cultural relics and industrial manufacturing. However, the high cost of printing materials and equipment operation and maintenance has greatly restricted the development of additive manufacturing technology.

[0003] At present, most of the additive manufacturing printing powder supply devices on the market have relatively simple functions and most of them still complete the powder replenishment of the printing equipment by manually adding or carrying powder. Especially when printing small target parts, only a small part of the materials are involved in the printing. Most of the powder is collected by the residual powder tank through the powder drop port, and then other steps such as manual drying and screening are carried out. The process has a low degree of automation and low efficiency. When changing the printing material, the residual powder in the channel leads to poor molding effect of subsequent prints, and the powder environment will also cause a certain degree of damage to the environment and human body. The target parts are generally in an inert gas environment during the SLM printing process. When a print is completed, the inert gas in the molding room will be discharged to the outside. This operation will cause the printing powder to be discharged into the external environment along with the gas, thereby affecting human health and the environment, and increasing the equipment operation cost. Utility Model Content

[0004] The embodiment of the present application solves the problem of low efficiency in the prior art of completing the powder replenishment process of the printing equipment by manually adding or transporting powder by providing a circulating powder supply system for an SLM printing equipment.

[0005] In order to achieve the above-mentioned purpose, the embodiment of the utility model provides a circulating powder supply system for SLM printing equipment, including a residual powder transfer tank, the upper interface of the residual powder transfer tank is connected to the powder drop port of the internal molding chamber of the SLM printing equipment through a ninth electric butterfly valve and a powder drop pipeline, and the lower interface of the residual powder transfer tank is connected to the gas circuit powder delivery pipeline through a tenth electric butterfly valve;

[0006] The output port in the middle of the argon tank is connected to the SLM printing device through the Hth electric ball valve and the first argon delivery pipe;

[0007] The output port at the bottom of the argon tank is connected to the blower inlet through the second argon delivery pipe, and the blower outlet is connected to the inlet of the gas circuit powder delivery pipeline;

[0008] The air inlet of the cyclone separator is connected to the outlet of the air powder conveying pipeline through the fifth first stop valve; the powder outlet at the bottom of the cyclone separator is connected to the inlet of the powder drying chamber through the second electric butterfly valve and the connecting pipeline, and a photoelectric sensor is arranged in the connecting pipeline; the powder outlet at the bottom of the powder drying chamber is connected to the inlet of the ultrasonic screening device through the third electric butterfly valve, and the powder discharge port at the bottom of the ultrasonic screening device is connected to the main powder storage tank through the fifth ninth electric butterfly valve and the screening powder drop pipe; the waste discharge port at the bottom of the ultrasonic screening device is connected to the waste collection cabin through the fourth third electric butterfly valve and the waste discharge pipeline;

[0009] The output port on one side of the airbag is connected to the inlet of the arch-breaking pipeline through the Cth electric ball valve, and the outlet of the arch-breaking pipeline is respectively connected to the main powder storage tank, the feed tank, the top powder storage tank and the transfer powder tank through multiple branch pipelines, and electric ball valves are provided on the multiple branch pipelines;

[0010] The transfer powder tank is movably installed through a moving mechanism. The transfer powder tank is arranged between the main powder storage tank and the machine top powder storage tank in the vertical direction. A funnel pipe for cooperating with the bottom outlet of the main powder storage tank is arranged on the top of the transfer powder tank. A telescopic butt joint pipe for cooperating with the top inlet of the machine top powder storage tank is arranged at the lower end of the transfer powder tank.

[0011] The top powder storage tank is arranged on the top of the SLM printing device, and the outlet of the top powder storage tank is connected to the inlet of the top of the SLM printing device;

[0012] The lower part of the feed tank is connected to the gas powder conveying pipeline through the eleventh electric butterfly valve; the SLM printer group is arranged on the gas powder conveying pipeline.

[0013] In one possible implementation, the airbag is disposed in a stainless steel shell, the output port on the other side of the airbag is connected to the air compressor inlet through a third electric ball valve, an air compressor pressure gauge is provided on the air compressor, and the air compressor outlet is connected to the argon tank inlet through a fourth electric ball valve.

[0014] In a possible implementation, the upper end of the funnel pipe is a funnel section, the inner wall of the small mouth end of the funnel section is provided with a sealing ring, and the lower part of the funnel pipe is provided with a seventh electric butterfly valve.

[0015] In one possible implementation, the telescopic butt joint tube includes an upper butt joint tube, a bellows and a lower butt joint tube connected in sequence, the upper butt joint tube and the lower butt joint tube are both provided with abutment rings, a plurality of compression springs are circumferentially arranged on the bellows, and the two ends of the compression springs are respectively connected to the abutment rings of the upper butt joint tube and the abutment rings of the lower butt joint tube.

[0016] In one possible implementation, the moving mechanism includes a supporting truss, a longitudinal feeding mechanism and a transverse feeding mechanism; the supporting truss is fixedly installed, the longitudinal feeding mechanism is fixedly installed on both sides of the supporting truss, the two ends of the transverse feeding mechanism are installed on the sliding end of the longitudinal feeding mechanism, and the transfer powder tank is installed on the sliding end of the transverse feeding mechanism.

[0017] In a possible implementation, a third manual butterfly valve for manual powder addition is provided on the upper portion of the feed tank.

[0018] In a possible implementation, the air outlet of the cyclone separator is connected to the inlet of the baffle dust collector, the outlet of the baffle dust collector is connected to the inlet of the bag dust collector, and the outlet of the bag dust collector is connected to the inlet of the three-way electric exhaust valve;

[0019] The upper part of the airbag is connected to the outlet of the first vertical pipe through the second electric ball valve, and the inlet of the first vertical pipe is connected to the outlet of the three-way electric exhaust valve.

[0020] In a possible implementation, a humidity sensor and a temperature sensor are provided inside the powder drying chamber; and a spiral stirring blade is provided inside the drying cavity of the powder drying chamber.

[0021] In a possible implementation, material level detection sensors are provided inside the main powder storage tank, the replenishing tank, the machine top powder storage tank and the transfer powder tank.

[0022] One or more technical solutions provided in the embodiments of the present utility model have at least the following technical effects or advantages:

[0023] The embodiment of the utility model provides a circulating powder supply system for SLM printing equipment. The utility model solves the problem that the powder supply device in the prior art cannot realize circulating powder supply and multiple devices cannot supply powder simultaneously, and solves the problem of recycling the inert gas source and self-cleaning of the powder pipeline and equipment. The utility model can effectively solve the labor problem, improve the operating reliability of the equipment, and at the same time, the SLM printing equipment and the argon gas in the pipeline can be effectively recycled for secondary utilization; the equipment system can be regulated in real time, effectively improving the control of the equipment and realizing intelligent control; through the adjustment of the pressure gauge equipment, the pressure sensor equipment and the air compressor equipment, the safety hazard caused by the excessive pressure in the argon tank and the air bag is avoided; through intelligent monitoring, the powder drying, screening, gas-solid separation and circulation supply are realized, and the cost is effectively saved; through the chessboard positioning system, the positioning of the transfer powder tank in the working area is effectively and accurately completed; through the Internet of Things system, the interaction between the equipment and the control room is realized, and the operating condition of the equipment can be monitored in real time; through the principle of gas arch breaking, the problem of powder bridging in the powder supply tank is solved, and the utilization efficiency of the powder is effectively improved; the use of argon tanks and blowers can effectively process residual powder, reduce environmental pollution and the harm of powder floating in the air to the human body. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments recorded in the present application, and for ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0025] Figure 1 A schematic diagram of the structure of a circulating powder supply system for an SLM printing device provided in an embodiment of the utility model.

[0026] Figure 2 A schematic structural diagram of a moving mechanism provided in an embodiment of the utility model.

[0027] Figure 3 A schematic diagram of the principle of chessboard positioning provided by an embodiment of the utility model.

[0028] Figure 4 This is a schematic structural diagram of a transfer powder tank provided in an embodiment of the utility model.

[0029] Figure 5 A schematic structural diagram of a telescopic butt joint pipe provided in an embodiment of the utility model.

[0030] Figure numerals: 1-residual powder transfer tank; 2-9th electric butterfly valve; 3-10th electric butterfly valve; 4-air powder conveying pipeline; 5-argon tank; 6-Hth electric ball valve; 7-blower; 8-cyclone separator; 9-51st stop valve; 10-2nd electric butterfly valve; 11-powder drying chamber; 12-3rd electric butterfly valve; 13-ultrasonic screening device; 14-59th electric butterfly valve; 15-total powder storage tank; 16-43rd electric butterfly valve; 17-waste collection cabin; 18-airbag; 19-Cth electric ball valve; 20-arch breaking pipeline; 21-feeding tank; 22-top powder storage tank; 23-transfer powder tank; 24-funnel pipeline; 25-telescopic docking Tube; 26-eleventh electric butterfly valve; 27-SLM printer group; 28-air compressor; 29-fourth electric ball valve; 30-sealing ring; 31-seventh electric butterfly valve; 32-upper butt pipe; 33-bellows; 34-lower butt pipe; 35-butt ring; 36-compression spring; 37-support truss; 38-longitudinal feed mechanism; 39-lateral feed mechanism; 40-baffle dust collector; 41-bag dust collector; 42-three-way electric exhaust valve; 43-first vertical pipe; 44-first electric ball valve; 45-first pressure sensor; 46-Y-type filter; 47-flow rate sensor; 48-second pressure sensor; 49-oxygen content monitor. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments in the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0032] In the description of the embodiments of the present utility model, it should be noted that the orientations or positional relationships indicated by the terms "center", "upper", "lower", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the embodiments of the present utility model and simplifying the description, rather than indicating or implying that the devices or elements referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limitations on the present utility model. The terms "first", "second", and "third" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the embodiments of the present utility model can be understood according to the specific circumstances.

[0033] like Figures 1 to 5 As shown, the SLM printing equipment circulating powder supply system provided by the embodiment of the utility model includes a residual powder transfer tank 1, the upper interface of the residual powder transfer tank 1 is connected to the powder drop port of the internal molding chamber of the SLM printing equipment through the ninth electric butterfly valve 2 and the powder drop pipeline, and the lower interface of the residual powder transfer tank 23 is connected through the tenth electric butterfly valve 3 and the air powder conveying pipeline 4.

[0034] The output port in the middle of the argon tank 5 is connected to the SLM printing device through the Hth electric ball valve 6 and the first argon delivery pipe.

[0035] The output port at the bottom of the argon tank 5 is connected to the inlet of the blower 7 through the second argon delivery pipe, and the outlet of the blower 7 is connected to the inlet of the gas powder conveying pipeline 4.

[0036] The air inlet of the cyclone separator 8 is connected to the outlet of the air powder conveying pipeline 4 through the fifth first stop valve 9. The powder outlet at the bottom of the cyclone separator 8 is connected to the inlet of the powder drying chamber 11 through the second electric butterfly valve 10 and the connecting pipeline, and a photoelectric sensor is arranged in the connecting pipeline. The powder outlet at the bottom of the powder drying chamber 11 is connected to the inlet of the ultrasonic screening device 13 through the third electric butterfly valve 12, and the powder discharge port at the bottom of the ultrasonic screening device 13 is connected to the main powder storage tank 15 through the fifth ninth electric butterfly valve 14 and the screening powder drop pipe. The waste discharge port at the bottom of the ultrasonic screening device 13 is connected to the waste collection cabin 17 through the fourth third electric butterfly valve 16 and the waste discharge pipeline.

[0037] The output port on one side of the airbag 18 is connected to the inlet of the arch breaking pipe 20 through the Cth electric ball valve 19, and the outlet of the arch breaking pipe 20 is respectively connected to the interior of the main powder storage tank 15, the feed tank 21, the top powder storage tank 22 and the transfer powder tank 23 through multiple branch pipes, and electric ball valves are provided on the multiple branch pipes.

[0038] The transfer powder tank 23 is movably installed by a moving mechanism. The transfer powder tank 23 is arranged between the main powder storage tank 15 and the top powder storage tank 22 in the vertical direction. A funnel pipe 24 is arranged on the top of the transfer powder tank 23 for cooperating with the bottom outlet of the main powder storage tank 15, and a telescopic docking pipe 25 is arranged on the lower end of the transfer powder tank 23 for cooperating with the top inlet of the top powder storage tank 22.

[0039] The top powder storage tank 22 is arranged on the top of the SLM printing device, and the outlet of the top powder storage tank 22 is connected to the inlet of the top of the SLM printing device.

[0040] The lower part of the feed tank 21 is connected to the gas-powder conveying pipeline 4 through the eleventh electric butterfly valve 26. The SLM printer group 27 is arranged on the gas-powder conveying pipeline 4.

[0041] It should be noted that there are two residual powder transfer tanks 1, which are symmetrically arranged on the SLM printing device. Inert gas argon is used as a protective gas. After one printing is completed, the argon in the molding chamber will not be discharged to the outside. The recovery through the airbag 18 can prevent the printing powder from being discharged into the external environment along with the gas, thereby affecting the environment and human health.

[0042] A pressure gauge and a liquid level gauge are arranged in the argon tank 5. A mica heating sheet is arranged inside the powder drying chamber 11.

[0043] In this embodiment, the airbag 18 is arranged in a stainless steel shell, the output port on the other side of the airbag 18 is connected to the inlet of the air compressor 28 through the third electric ball valve, the air compressor 28 is provided with an air compressor pressure gauge, and the outlet of the air compressor 28 is connected to the inlet of the argon tank 5 through the fourth electric ball valve 29. The airbag 18 is a common airbag 18 of a pneumatic element, and a pressure gauge is arranged inside it.

[0044] In this embodiment, the upper end of the funnel pipe 24 is a funnel section, a sealing ring 30 is provided on the inner wall of the small mouth end of the funnel section, and a seventh electric butterfly valve 31 is provided at the lower part of the funnel pipe 24 .

[0045] It should be noted that the funnel section is convenient for receiving powder, and the sealing ring 30 is used to improve the sealing performance.

[0046] In this embodiment, the telescopic docking tube 25 includes an upper docking tube 32, a bellows 33 and a lower docking tube 34 which are connected in sequence. The upper docking tube 32 and the lower docking tube 34 are both provided with abutment rings 35. The bellows 33 is circumferentially provided with a plurality of compression springs 36. The two ends of the compression spring 36 are respectively connected to the abutment ring 35 of the upper docking tube 32 and the abutment ring 35 of the lower docking tube 34.

[0047] It should be noted that after the telescopic butt tube 25 and the top inlet of the top powder storage tank 22 are matched, the bellows 33 and the compression spring 36 are both contracted, so that a certain pressure exists between the telescopic butt tube 25 and the top inlet of the top powder storage tank 22, thereby improving the sealing performance.

[0048] In this embodiment, the moving mechanism includes a support truss 37, a longitudinal feeding mechanism 38 and a transverse feeding mechanism 39. The support truss 37 is fixedly installed, the longitudinal feeding mechanism 38 is fixedly installed on both sides of the support truss 37, the two ends of the transverse feeding mechanism 39 are installed on the sliding end of the longitudinal feeding mechanism 38, and the transfer powder tank 23 is installed on the sliding end of the transverse feeding mechanism 39.

[0049] It should be noted that both the longitudinal feeding mechanism 38 and the transverse feeding mechanism 39 adopt a nut-screw driving mechanism to achieve the adjustment of the transfer powder tank 23 at any position of the X-axis and the Y-axis. This connection method not only allows the circulating powder supply system to meet the powder supply needs of multiple machines, but also reduces the docking vibration generated by the printing equipment when supplying powder, thereby ensuring the quality of the printed parts. The transfer powder tank 23 adopts a more effective chessboard positioning method for positioning the total powder tank and the transfer powder tank 23, which can quickly and accurately locate the position of the top powder storage tank 22 and reduce the amount of calculation of the controller. The chessboard positioning principle of this embodiment is as follows: the working plane is calibrated with the initial position of the total material tank as the origin, and the working plane is divided into X and Y directions according to the chessboard format. The horizontal feeding mechanism 39 corresponds to the X direction, and similarly the longitudinal feeding mechanism 38 corresponds to the Y direction. Through the control of the motor, the feeding speed of the feeding mechanism in X and Y is 5 cm / s each time. When the feeding mechanism is close to the SLM printing device or the total material tank as shown in the figure, the feeding speed is adjusted to 1 mm / s through the stepper motor, that is, when the feeding mechanism approaches the target point in the X or Y direction, the approach distance is set to 1 cm, and its feeding speed is slowed down to align the top powder storage tank 22 or the total material tank for feeding or replenishing.

[0050] In this embodiment, a third manual butterfly valve for manual powder addition is provided on the upper part of the feed tank 21.

[0051] In this embodiment, the air outlet of the cyclone separator 8 is connected to the inlet of the baffle dust collector 40 , the outlet of the baffle dust collector 40 is connected to the inlet of the bag dust collector 41 , and the outlet of the bag dust collector 41 is connected to the inlet of the three-way electric exhaust valve 42 .

[0052] The upper portion of the airbag 18 is connected to the outlet of the first vertical pipe 43 through the second electric ball valve, and the inlet of the first vertical pipe 43 is connected to the outlet of the three-way electric exhaust valve 42 .

[0053] It should be noted that the gas discharged from the cyclone separator 8 is further recovered through the baffle dust collector 40 and the bag dust collector 41, and the separated gas enters the interior of the airbag 18.

[0054] In this embodiment, a humidity sensor and a temperature sensor are provided inside the powder drying chamber 11. A spiral stirring blade is provided inside the drying cavity of the powder drying chamber 11.

[0055] It should be noted that the spiral stirring blades further improve the drying efficiency of the powder drying chamber 11 .

[0056] In this embodiment, the second argon gas delivery pipe is provided with a first electric ball valve 44 and a first pressure sensor 45 in sequence, and the gas-powder conveying pipeline 4 is provided with a Y-type filter 46 and a flow rate sensor 47 in sequence on the pipeline between the lower interface of the residual powder transfer tank 23 and the outlet of the blower 7. The gas-powder conveying pipeline 4 is provided with a second pressure sensor 48 and an oxygen content monitor 49 in sequence on the pipeline on the side of the lower interface of the residual powder transfer tank 23 away from the flow rate sensor 47.

[0057] The SLM printer group 27 is arranged on the pipeline of the air powder conveying pipeline 4 between the lower interface of the residual powder transfer tank 23 and the second pressure sensor 48, and the lower part of the feed tank 21 is connected to the air powder conveying pipeline 4 through the eleventh electric butterfly valve 26 and is located on the side of the oxygen content detector away from the blower 7.

[0058] In this embodiment, material level detection sensors are arranged inside the main powder storage tank 15 , the replenishing tank 21 , the top powder storage tank 22 and the transfer powder tank 23 .

[0059] The SLM printing equipment circulating powder supply system provided by the embodiment of the utility model includes a powder supply working condition, a pressure detection working condition and a pipeline self-cleaning working condition when the SLM printing equipment is working.

[0060] The powder replenishment operation includes the following steps:

[0061] The Hth electric ball valve 6 is opened, and the argon tank 5 is inflated into the internal molding chamber of the SLM printing device through the first argon delivery pipe, and the SLM printing device starts to work.

[0062] When the material level of the top powder storage tank 22 is too low, the transfer powder tank 23 is moved to the top of the top powder storage tank 22 by the moving mechanism. After the telescopic docking pipe 25 at the bottom of the transfer powder tank 23 is docked with the upper inlet of the top powder storage tank 22, the transfer powder tank 23 delivers powder to the top powder storage tank 22.

[0063] When the material level of the transfer powder tank 23 is too low, the transfer powder tank 23 is moved to the bottom of the main powder storage tank 15 by the moving mechanism. After the funnel pipe 24 on the upper part of the transfer powder tank 23 is connected with the lower outlet of the main powder storage tank 15, the main powder storage tank 15 delivers powder to the transfer powder tank 23.

[0064] When the material level of the total powder storage tank 15 is too low, the blower 7 is started to form an airflow of a set pressure inside the air powder conveying pipeline 4. The powder in the residual powder transfer tank 1 enters the air powder conveying pipeline 4 under the action of the airflow and is transported to the cyclone separator 8 for separation of powder. The separated powder is then sent to the powder drying chamber 11 for drying. The dried powder enters the ultrasonic screening device 13 for screening, and the screened powder enters the total powder storage tank 15.

[0065] When the material level in the feed tank 21 is too low, the staff manually adds powder through the third manual butterfly valve.

[0066] When the material level of the residual material transfer powder tank 23 is too low, open the eleventh electric butterfly valve 26 and the first electric ball valve 44, start the blower 7, and the blower 7 sends the powder in the replenishing tank 21 to the main powder storage tank 15, and then enters the transfer powder tank 23, the top powder storage tank 22 and the SLM printing device in turn, and then is sent to the residual material transfer powder tank 23.

[0067] In this embodiment, the airbag 18 is arranged in a stainless steel shell, and the output port on the other side of the airbag 18 is connected to the inlet of the air compressor 28 through the third electric ball valve. The air compressor 28 is provided with an air compressor pressure gauge, and the outlet of the air compressor 28 is connected to the inlet of the argon tank 5 through the fourth electric ball valve 29.

[0068] The pressure test procedure includes the following steps:

[0069] When the pressure inside the airbag 18 reaches the set value, the third electric ball valve is opened and the air compressor 28 is started. The air compressor 28 compresses the argon gas in the airbag 18. When the pressure inside the air compressor 28 reaches the set pressure, the fourth electric ball valve 29 is opened to input the compressed argon gas into the argon tank 5.

[0070] The staff manually adds liquid argon through the liquid inlet of the argon tank 5.

[0071] In this embodiment, when the material level of the total powder storage tank 15 is too low, the first electric ball valve 44 is opened, the ninth electric butterfly valve 2 and the second electric butterfly valve 10 are closed, and the blower 7 is started to form an airflow of a set pressure inside the air powder conveying pipeline 4, and the three-way electric exhaust valve 42 is opened. The flow velocity in the air powder conveying pipeline 4 is detected by the flow velocity sensor 47, and the air pressure in the air powder conveying pipeline 4 is detected by the first pressure sensor 45 and the second pressure sensor 48. When the flow velocity is greater than the set value and the pressure difference of the air pressure is within the set threshold, the oxygen content monitor 49 detects the oxygen content in the air powder conveying pipeline 4. When the oxygen content reaches the standard, the three-way electric exhaust valve 42 is closed and the tenth electric butterfly valve 3 is opened.

[0072] When the flow rate is less than the set value and the pressure difference of the air pressure is greater than the set threshold, check whether the Y-type filter 46 is blocked. If the Y-type filter 46 is not blocked, check whether the pipeline is blocked.

[0073] The powder in the residual powder transfer tank 1 enters the air powder conveying pipeline 4 under the action of the airflow and is transported to the cyclone separator 8 for powder separation. The photoelectric sensor detects the accumulation of powder in the connecting pipeline. When powder accumulates, the second electric butterfly valve 10 is opened and the third electric butterfly valve 12 is closed. The separated powder is then sent to the powder drying chamber 11 for drying. The humidity sensor and the temperature sensor detect the humidity and temperature in the powder drying chamber 11. When the humidity and temperature meet the requirements, the third electric butterfly valve 12 is opened and the powder drying chamber 11 is closed. The dried powder enters the ultrasonic screening device 13 for screening, and the screened powder enters the total powder storage tank 15.

[0074] In this embodiment, the pipeline self-cleaning condition includes the following steps:

[0075] Close the fourth third electric butterfly valve 16, connect the telescopic butt joint 25 at the bottom of the transfer powder tank 23 to the waste collection cabin 17 through a pipeline, open the first electric ball valve 44, start the blower 7, and then blow the residual powder in the air powder conveying pipeline 4, the cyclone separator 8, the powder drying chamber 11, the ultrasonic screening device 13, the main powder storage tank 15, and the transfer powder tank 23 into the waste collection cabin 17.

[0076] When the material levels of the main powder storage tank 15, the top powder storage tank 22 and the transfer powder tank 23 are obviously stagnant, open the Cth electric ball valve 19 and the electric ball valves on the branch pipelines of the main powder storage tank 15, the top powder storage tank 22 and the transfer powder tank 23 to perform a gas arch breaking.

[0077] It should be noted that the argon gas in the expansion airbag 18 is sent into the powder tank. When the powder supply mode is running, the powder bridges in each powder tank are broken, which effectively solves the problem of powder bridging and improves the efficiency of equipment supply and powder circulation.

[0078] Pressure sensors are provided in the argon tank 5 and the air bag 18. The signals measured by the pressure sensors are transmitted to the control room through the DTU module. When the pressure is too high, the display screen in the control room will show the pressure information and the alarm will sound to remind the staff to discharge the gas in the argon tank 5 or the system to compress the excess argon into the argon tank 5 through the air compressor 28, which further improves the utilization rate of the argon gas and effectively solves the safety hazard caused by excessive pressure in the tank.

[0079] A Y-type filter 46 for gas-solid separation is provided on the air powder conveying pipeline 4. At the same time, a pipeline bending process is performed at the pipeline position where the Y-type filter 46 is installed, making it more difficult for powder to enter the blower 7 position, thereby preventing the blower 7 from being damaged due to powder blockage.

[0080] When the flow rate in the pipeline is lower than the set threshold or the difference between the pressure sensors at both ends is higher than the specified difference, the alarm in the control room will sound to remind the staff to check whether the filter element or other parts of the pipeline are blocked.

[0081] A liquid level gauge is provided in the argon tank 5, and the liquid level gauge outputs a signal to the control room through the PLC controller. When the liquid level is low, the controller receives a signal, and the display screen in the control room shows that the liquid level is insufficient. At the same time, an alarm sounds to remind the driver to add liquid argon.

[0082] The cyclone separator 8, the powder drying chamber 11, the ultrasonic screening device 13 and the total powder storage tank 15 are vertically integrated on the truss in space through connecting pipes, and each interface has valves of different specifications, which not only facilitates the maintenance of the equipment, but also reduces the use of space. A spiral stirring blade is set in the powder drying chamber 11, which allows the powder to circulate on the blade rail to a certain extent, so that the powder is heated evenly, reducing the drying time and improving the efficiency of drying the powder. The photoelectric sensor is used to detect whether there is powder accumulation in the connecting pipe.

[0083] When it is necessary to replace other printing metal powders, the original pipeline needs to be cleaned to prevent the new printing material from being contaminated. Therefore, at the beginning of the system operation, the control interface will remind the staff whether to end the working condition. When the staff chooses to end the working condition, the control interface will remind the staff whether self-cleaning pipelines are needed. When the staff confirms the self-cleaning pipeline, because the molding time of powder bridging is random and uncertain, for the arch breaking operation, when the material level detection shows obvious stagnation, open the electric ball valve on the branch pipeline of the main powder storage tank 15, the top powder storage tank 22, and the transfer powder tank 23 to perform a gas arch breaking.

[0084] In this embodiment, when the blower 7 is started, the first electric ball valve 44 is opened to allow the argon gas in the argon tank 5 to enter the blower 7 and then enter the gas powder conveying pipeline 4 .

[0085] The utility model solves the problem that the powder supply device in the prior art cannot realize the cyclic powder supply and the simultaneous powder supply of multiple devices, and solves the problem of recycling the inert gas source and the self-cleaning of the powder pipeline and equipment. The utility model can effectively solve the labor problem, improve the operating reliability of the equipment, and at the same time, the SLM printing equipment and the argon gas in the pipeline can be effectively recycled for a second time. The equipment system can be regulated in real time, effectively improving the control of the equipment and realizing intelligent control. Through the adjustment of the pressure gauge equipment, the pressure sensor equipment and the air compressor 28 equipment, the safety hazard caused by the excessive pressure in the argon tank 5 and the air bag 18 is avoided. Through intelligent monitoring, powder drying, screening, gas-solid separation and cyclic supply are realized, effectively saving costs. Through the chessboard positioning system, the positioning of the transfer powder tank 23 in the working area is effectively and accurately completed. The interaction between the equipment and the control room is realized through the Internet of Things system, and the operating conditions of the equipment can be monitored in real time. Through the principle of gas arch breaking, the problem of powder bridging in the powder supply tank is solved, and the utilization efficiency of the powder is effectively improved. The residual powder can be effectively processed by using the argon tank 5 and the blower 7, thereby reducing the pollution of the environment and the harm of the powder floating in the air to the human body.

[0086] The control methods involved in this embodiment, such as the DTU module, the PLC controller, and the chessboard positioning method, are all existing technologies, and this embodiment does not further elaborate on the specific control principles.

[0087] In this embodiment, it is obvious to those skilled in the art that the present invention is not limited to the details of the above exemplary embodiment, and that the present invention can be implemented in other specific forms without departing from the spirit or basic features of the present invention. Therefore, no matter from which point of view, the embodiment should be regarded as exemplary and non-restrictive, and the scope of the present invention is defined by the appended claims rather than the above description, and therefore it is intended that all changes falling within the meaning and scope of the equivalent elements of the claims are included in the present invention.

Claims

1. A circulating powder supply system for SLM printing equipment, characterized in that: It comprises a residual powder transfer tank (1), the upper interface of the residual powder transfer tank (1) is connected to the powder drop port of the internal molding chamber of the SLM printing device through a ninth electric butterfly valve (2) and a powder drop pipeline, and the lower interface of the residual powder transfer tank (23) is connected to the air powder delivery pipeline (4) through a tenth electric butterfly valve (3); The output port in the middle of the argon tank (5) is connected to the SLM printing device via the Hth electric ball valve (6) and the first argon delivery pipe; The output port at the bottom of the argon tank (5) is connected to the inlet of the blower (7) through a second argon delivery pipe, and the outlet of the blower (7) is connected to the inlet of the gas powder delivery pipeline (4); The air inlet of the cyclone separator (8) is connected to the outlet of the air powder conveying pipeline (4) through a fifth first stop valve (9); the powder outlet at the bottom of the cyclone separator (8) is connected to the inlet of the powder drying chamber (11) through a second electric butterfly valve (10) and a connecting pipeline, and a photoelectric sensor is arranged in the connecting pipeline; the powder outlet at the bottom of the powder drying chamber (11) is connected to the inlet of the ultrasonic screening device (13) through a third electric butterfly valve (12), and the powder discharge port at the bottom of the ultrasonic screening device (13) is connected to the main powder storage tank (15) through a fifth ninth electric butterfly valve (14) and a screening powder drop pipe; the waste discharge port at the bottom of the ultrasonic screening device (13) is connected to the waste collection cabin (17) through a fourth third electric butterfly valve (16) and a waste discharge pipeline; The output port on one side of the airbag (18) is connected to the inlet of the arch-breaking pipeline (20) through the Cth electric ball valve (19), and the outlet of the arch-breaking pipeline (20) is respectively connected to the interior of the main powder storage tank (15), the feed tank (21), the machine top powder storage tank (22) and the transfer powder tank (23) through a plurality of branch pipelines, and electric ball valves are arranged on the plurality of branch pipelines; The transfer powder tank (23) is movably installed by a moving mechanism. The transfer powder tank (23) is arranged between the main powder storage tank (15) and the machine top powder storage tank (22) in the vertical direction. A funnel pipe (24) is arranged on the top of the transfer powder tank (23) for cooperating with the bottom outlet of the main powder storage tank (15). A telescopic butt joint pipe (25) is arranged on the lower end of the transfer powder tank (23) for cooperating with the top inlet of the machine top powder storage tank (22). The top powder storage tank (22) is arranged on the top of the SLM printing device, and the outlet of the top powder storage tank (22) is connected to the inlet of the top of the SLM printing device; The lower part of the feed tank (21) is connected to the gas-powder conveying pipeline (4) through the eleventh electric butterfly valve (26); the SLM printer group (27) is arranged on the gas-powder conveying pipeline (4).

2. The SLM printing equipment circulating powder supply system according to claim 1, characterized in that: The air bag (18) is arranged in a stainless steel shell, and the output port on the other side of the air bag (18) is connected to the inlet of an air compressor (28) through a third electric ball valve. The air compressor (28) is provided with an air compressor pressure gauge, and the outlet of the air compressor (28) is connected to the inlet of an argon gas tank (5) through a fourth electric ball valve (29).

3. The SLM printing equipment circulating powder supply system according to claim 2, characterized in that: The upper end of the funnel pipe (24) is a funnel section, the inner wall of the small opening end of the funnel section is provided with a sealing ring (30), and the lower part of the funnel pipe (24) is provided with a seventh electric butterfly valve (31).

4. The SLM printing equipment circulating powder supply system according to claim 3, characterized in that: The telescopic butt joint pipe (25) comprises an upper butt joint pipe (32), a bellows (33) and a lower butt joint pipe (34) which are connected in sequence. The upper butt joint pipe (32) and the lower butt joint pipe (34) are both provided with abutment rings (35). A plurality of compression springs (36) are arranged in the circumferential direction of the bellows (33). Two ends of the compression springs (36) are respectively connected to the abutment ring (35) of the upper butt joint pipe (32) and the abutment ring (35) of the lower butt joint pipe (34).

5. The SLM printing equipment circulating powder supply system according to claim 4, characterized in that: The moving mechanism comprises a supporting truss (37), a longitudinal feeding mechanism (38) and a transverse feeding mechanism (39); the supporting truss (37) is fixedly installed, the longitudinal feeding mechanism (38) is fixedly installed on both sides of the supporting truss (37), the two ends of the transverse feeding mechanism (39) are installed on the sliding end of the longitudinal feeding mechanism (38), and the transfer powder tank (23) is installed on the sliding end of the transverse feeding mechanism (39).

6. The powder supply circulation system for SLM printing equipment according to claim 5, characterized in that: A third manual butterfly valve for manually adding powder is arranged on the upper part of the feeding tank (21).

7. The SLM printing equipment circulating powder supply system according to claim 6, characterized in that: The air outlet of the cyclone separator (8) is connected to the inlet of the baffle dust collector (40), the outlet of the baffle dust collector (40) is connected to the inlet of the bag dust collector (41), and the outlet of the bag dust collector (41) is connected to the inlet of the three-way electric exhaust valve (42); The upper part of the air bag (18) is connected to the outlet of the first vertical pipe (43) through the second electric ball valve, and the inlet of the first vertical pipe (43) is connected to the outlet of the three-way electric exhaust valve (42).

8. The SLM printing equipment circulating powder supply system according to claim 7, characterized in that: A humidity sensor and a temperature sensor are arranged inside the powder drying chamber (11); and a spiral stirring blade is arranged inside the drying cavity of the powder drying chamber (11).

9. The SLM printing equipment circulating powder supply system according to claim 8, characterized in that: Material level detection sensors are arranged inside the main powder storage tank (15), the supplementary material tank (21), the machine top powder storage tank (22) and the transfer powder tank (23).

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