阅读说明：本技术 一种激光选区熔化3d打印生产线系统及控制方法 (Selective laser melting 3D printing production line system and control method ) 是由 谢林 代拴师 史梁 樊明洲 张鹏翔 张文韬 于 2020-12-02 设计创作，主要内容包括：一种激光选区熔化3D打印生产线系统及控制方法,涉及增材制造领域,包括供粉装置、上粉筒、收粉筒以及多个3D打印机；所述上粉筒依次设在每个3D打印机上部,所述收粉筒依次设在每个3D打印机下部,所述供粉装置分别与每个所述上粉筒和每个所述收粉筒连接。本发明提出了一种激光选区熔化3D打印生产线系统及控制方法,能够集中供粉,稳定运行,并达到节省粉末的效果。(A3D printing production line system for selective laser melting and a control method relate to the field of additive manufacturing and comprise a powder supply device, a powder feeding cylinder, a powder receiving cylinder and a plurality of 3D printers; go up the powder section of thick bamboo and establish in proper order on every 3D printer upper portion, receive the powder section of thick bamboo and establish in proper order in every 3D printer lower part, the powder supply device respectively with every go up the powder section of thick bamboo and every receive the powder section of thick bamboo and connect. The invention provides a selective laser melting 3D printing production line system and a control method, which can supply powder in a centralized manner, run stably and achieve the effect of saving powder.)

1. A selective laser melting 3D printing production line system is characterized by comprising a powder supply device, a powder feeding cylinder, a powder receiving cylinder and a plurality of 3D printers;

the powder feeding cylinder is sequentially arranged at the upper part of each 3D printer;

the powder collecting cylinders are sequentially arranged at the lower part of each 3D printer;

the powder supply device is respectively connected with each powder feeding cylinder and each powder collecting cylinder;

a powder section of thick bamboo and receive same confession powder device of powder section of thick bamboo sharing on a plurality of 3D printers can be with the unified effective cyclic utilization that concentrates of unnecessary powder that produces among the printing process, effectively reduces new powder addition in the course of working.

2. The selective laser melting 3D printing production line system according to claim 1, wherein the powder supply device comprises a filter sieve, a powder storage cylinder and a fan which are sequentially connected from top to bottom, a first communication valve is arranged between the filter sieve and the powder storage cylinder, and a second communication valve is arranged between the powder storage cylinder and the fan;

the upper side of the filter screen is also communicated with the lower side of the second communicating valve.

3. The selective laser melting 3D printing line system of claim 2, wherein the fan comprises a first circulating fan and a second circulating fan;

the first circulating fan is used for blowing powder from the powder receiving cylinder into the powder supply device;

the second circulating fan is used for blowing powder from the powder supply device into the upper powder barrel.

4. The selective laser melting 3D printing production line system according to claim 3, wherein the first circulating fan is connected with one side of the powder collecting cylinder, the other side of the powder collecting cylinder is connected with the filter sieve, and a powder return valve is arranged between the powder collecting cylinder and the filter sieve.

5. The selective laser melting 3D printing production line system according to claim 3, wherein the second circulating fan is connected with the lower side of the powder feeding cylinder, the upper side of the powder feeding cylinder is connected with the filter screen, and a powder supply valve is arranged between the powder feeding cylinder and the filter screen.

6. The selective laser melting 3D printing production line system according to claim 1, wherein a material level sensor and an oxygen content sensor are arranged in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the material level sensor can detect the powder content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the oxygen content sensor can detect the oxygen content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder.

7. The selective laser melting 3D printing line system as claimed in claim 6, wherein the level sensor comprises an upper sensor and a lower sensor;

when the upper sensor is triggered, the upper sensor indicates that the powder is full, and the powder supply is stopped;

when the lower sensor is triggered, the powder is lack, and the powder pumping is stopped.

8. A control method for a selective laser melting 3D printing production line is characterized in that the method is applied to the system according to any one of claims 1-7, and comprises the following steps:

s1: starting a production line, determining the number and serial number of printers, and setting safety parameters;

s2: when a lower sensor of the powder supply device is not triggered and meets the safety parameters set in the S1, starting printing;

s3: when an upper sensor of the powder collecting barrel is triggered, powder in the powder collecting barrel is pumped to a powder supply device;

s4: when a lower sensor of the powder feeding cylinder is triggered, powder in the powder supply device is blown to the powder feeding cylinder;

s5: the judgment steps of S2-S4 are repeated until all print jobs are completed.

9. The control method of the selective laser melting 3D printing production line according to claim 8, wherein the step S3 specifically comprises: when an upper sensor of the powder collecting barrel is triggered, the powder supply device is matched with a 3D printer number corresponding to the powder collecting barrel, a powder return valve corresponding to the number is opened, the first communication valve and the first circulating fan are opened, wind power is formed by the fans to pump out powder, the filter sieve is used for filtering coarse particles, fine powder is recycled into the powder storage barrel until a lower sensor of the powder collecting barrel is triggered, the fact that the powder collecting barrel is free of powder is indicated, and the powder supply device stops powder pumping.

10. The control method of the selective laser melting 3D printing production line according to claim 8, wherein the step S4 specifically comprises: when the lower sensor of last powder section of thick bamboo triggers, supply the powder device to match the 3D printer number that the powder section of thick bamboo corresponds, open the powder valve that supplies that the number corresponds, open second intercommunication valve and second circulating fan, utilize the fan to form wind-force and circulate the powder that supplies in the powder device stores up the powder section of thick bamboo and send to the powder section of thick bamboo in, the upper sensor that until the powder section of thick bamboo triggers, show to be full of the powder in the last powder section of thick bamboo this moment, supply the powder device to stop supplying the powder.

Technical Field

The invention relates to the field of additive manufacturing, in particular to a selective laser melting 3D printing production line system and a control method.

Background

And (3) selective laser melting 3D printing, wherein laser is used as an energy source, scanning is carried out on a metal powder bed layer by layer according to a pre-processed model slice file, and the metal powder is melted and solidified and then stacked layer by layer to form the required metal part. The technology has the advantages of high forming speed, excellent comprehensive mechanical property, capability of realizing forming of any complex structure and the like, and achieves good application effect in the fields of aerospace, medical treatment, automobiles and the like.

The popularization and application of the 3D printing technology for the melts in the laser selection areas can not avoid the production tasks of small quantities of metal parts in the actual production process, a 3D printer for supplying powder by a single feeding cylinder is adopted for production, and the problems of shutdown powder adding, great reduction of efficiency, product quality and the like due to insufficient powder in the production process exist. At present, mainstream 3D printer manufacturers at home and abroad adopt an automatic powder supply mode, and a set of automatic powder supply device is equipped to solve the problem of insufficient powder amount in the production process, but the working mode of a single 3D printer is still adopted, so that the actual production efficiency is still limited; in addition, be equipped with automatic feed equipment for each 3D printer, improved equipment cost by a wide margin, reduced the production benefit.

In order to solve the problems, the invention provides a centralized powder supply mode, a set of automatic powder supply device is used for supplying powder to a plurality of 3D printers to form a 3D printing production line, and the invention provides a corresponding control method for ensuring the reliable and stable operation of the production line.

Disclosure of Invention

In view of the above, the invention provides a selective laser melting 3D printing production line system and a control method thereof, which are composed of a set of powder supply device and a plurality of 3D printers, wherein the powder supply device and the 3D printers are controlled by using a PLC (programmable logic controller), so that the powder can be supplied in a centralized manner, the stable operation is realized, and the effect of saving powder is achieved.

According to a first aspect of the invention, a selective laser melting 3D printing production line system is provided, which comprises a powder supply device, a powder feeding cylinder, a powder receiving cylinder and a plurality of 3D printers;

go up the powder section of thick bamboo and establish in proper order on every 3D printer upper portion, receive the powder section of thick bamboo and establish in proper order in every 3D printer lower part, the powder supply device respectively with every go up the powder section of thick bamboo and every receive the powder section of thick bamboo and connect.

Further, the powder supply device comprises a filter sieve, a powder storage cylinder and a fan which are sequentially connected from top to bottom, a first communicating valve is arranged between the filter sieve and the powder storage cylinder, and a second communicating valve is arranged between the powder storage cylinder and the fan;

the upper side of the filter screen is also communicated with the lower side of the second communicating valve.

Further, the filter screen is a vibrating screen;

further, the fan comprises a first circulating fan and a second circulating fan;

the first circulating fan is used for blowing metal powder from the powder collecting cylinder into the powder supply device;

the second circulating fan is used for blowing metal powder from the powder supply device into the upper powder cylinder.

Furthermore, the first circulating fan is connected with one side of the powder collecting cylinder, the other side of the powder collecting cylinder is connected with the filter sieve, and a powder return valve is arranged between the powder collecting cylinder and the filter sieve.

Furthermore, the second circulating fan is connected with the lower side of the powder feeding cylinder, the upper side of the powder feeding cylinder is connected with the filter sieve, and a powder supply valve is arranged between the powder feeding cylinder and the filter sieve.

Further, a material level sensor and an oxygen content sensor are arranged in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the material level sensor can detect the powder content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the oxygen content sensor can detect the oxygen content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder.

Further, the level sensor comprises an upper sensor and a lower sensor;

when the upper sensor is triggered, the upper sensor indicates that the powder is full, and the powder supply is stopped;

when the lower sensor is triggered, the powder is lack, and the powder pumping is stopped.

Further, the upper sensors are respectively arranged at the upper parts of the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the lower sensors are respectively arranged at the lower parts of the powder supply device, the powder feeding cylinder and the powder collecting cylinder.

According to a second aspect of the present invention, there is provided a laser selective melting 3D printing production line control method applied to the system as described above, comprising the steps of:

s1: starting a production line, determining the number and serial number of printers, and setting safety parameters;

s2: when a lower sensor of the powder supply device is not triggered and meets the safety parameters set in the S1, starting printing;

s3: when an upper sensor of the powder collecting barrel is triggered, powder in the powder collecting barrel is pumped to a powder supply device;

s4: when a lower sensor of the powder feeding cylinder is triggered, powder in the powder supply device is blown to the powder feeding cylinder;

s5: the judgment steps of S2-S4 are repeated until all print jobs are completed.

Further, the S3 specifically includes: when an upper sensor of the powder collecting barrel is triggered, the powder supply device is matched with a 3D printer number corresponding to the powder collecting barrel, a powder return valve corresponding to the number is opened, the first communication valve and the first circulating fan are opened, wind power is formed by the fans to pump out metal powder, the filter sieve is used for filtering coarse particles, fine powder is recycled into the powder storage barrel until a lower sensor of the powder collecting barrel is triggered, the fact that the powder collecting barrel is free of powder is indicated, and the powder supply device stops powder pumping.

Further, the S4 specifically includes: when the lower sensor of last powder section of thick bamboo triggers, supply the powder device to match the 3D printer number that the powder section of thick bamboo corresponds, open the powder valve that supplies that the number corresponds, open second intercommunication valve and second circulating fan, utilize the fan to form wind-force and circulate the powder that supplies in the powder device stores up the powder section of thick bamboo and send to the powder section of thick bamboo in, the upper sensor that until the powder section of thick bamboo triggers, show to be full of the powder in the last powder section of thick bamboo this moment, supply the powder device to stop supplying the powder.

Compared with the prior art, the selective laser melting 3D printing production line system and the control method have the following advantages:

(1) the automatic powder supply of the 3D printer is realized, on one hand, the time consumed by stopping, adding powder, re-inflating and manually sieving powder is saved, and the production efficiency is greatly improved; on the other hand, the consumption of inert gas is reduced, and the 3D printing production cost is reduced;

(2) the automatic powder supply is used for replacing the original manual shutdown powder adding, so that the non-accidental shutdown of the printer during the working period is effectively avoided, and the quality consistency of 3D printing parts is ensured;

(3) realizes the control of a production line formed by a plurality of 3D printers, the printers are debugged in a unified way and work independently,

the production efficiency of small-batch metal parts is effectively improved;

(4) many 3D printers share one set of powder supply device for the extravagant unnecessary powder of printing in-process is concentrated and is collected same powder supply device cyclic utilization once more, can effectively reduce new powder addition in small batch processing.

Drawings

The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention and not to limit the invention.

In the drawings:

FIG. 1 is a schematic view of a selective laser melting 3D printing line system according to the present invention;

FIG. 2 is a schematic view of the connection between a single 3D printer and a feeding device according to the present invention;

FIG. 3 is a schematic view of the connection of a plurality of 3D printers and a feeding device according to the present invention;

FIG. 4 is a schematic view of the connection between the powder collecting barrel and the powder supplying device according to the present invention;

FIG. 5 is a schematic view of the connection between the upper powder cartridge and the powder feeder according to the present invention;

fig. 6 is a schematic diagram of the control method of the present invention.

Detailed Description

Reference will now be made in detail to the exemplary embodiments, examples of which are illustrated in the accompanying drawings. When the following description refers to the accompanying drawings, like numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Rather, they are merely examples of apparatus and methods consistent with certain aspects of the invention, as detailed in the appended claims.

The terms first, second and the like in the description and in the claims of the present invention are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It is to be understood that the data so used is interchangeable under appropriate circumstances such that the embodiments of the invention described herein are, for example, capable of operation in sequences other than those illustrated or otherwise described herein. Furthermore, the terms "comprises," "comprising," and "having," and any variations thereof, are intended to cover a non-exclusive inclusion, such that a process, method, system, article, or apparatus that comprises a list of steps or elements is not necessarily limited to those steps or elements expressly listed, but may include other steps or elements not expressly listed or inherent to such process, method, article, or apparatus.

A plurality, including two or more.

And/or, it should be understood that, as used herein, the term "and/or" is merely one type of association that describes an associated object, meaning that three types of relationships may exist. For example, a and/or B, may represent: a exists alone, A and B exist simultaneously, and B exists alone.

As shown in fig. 1-3, a laser selective melting 3D printing production line system comprises a set of powder supply device and a plurality of 3D printers, wherein the powder supply device and the 3D printers are controlled by a PLC, a powder inlet cylinder is arranged above each 3D printer, a powder receiving cylinder is arranged below each 3D printer, and the powder supply device is respectively connected with each powder inlet cylinder and each powder receiving cylinder.

The powder supply device comprises a filter sieve, a powder storage cylinder and a fan which are sequentially connected from top to bottom, a first communicating valve is arranged between the filter sieve and the powder storage cylinder, and a second communicating valve is arranged between the powder storage cylinder and the fan;

the upper side of the filter screen is also communicated with the lower side of the second communicating valve.

The fan comprises a first circulating fan and a second circulating fan;

the first circulating fan is used for blowing the metal powder from the powder receiving cylinder into the powder supply device;

the second circulating fan is used for blowing the metal powder from the powder supply device to the powder feeding cylinder.

As shown in fig. 4, the first circulating fan is connected with one side of the powder collecting cylinder, the other side of the powder collecting cylinder is connected with the filter sieve, and a powder return valve is arranged between the powder collecting cylinder and the filter sieve.

As shown in fig. 5, the second circulating fan is connected with the lower side of the upper powder cylinder, the upper side of the upper powder cylinder is connected with the filter sieve, and a powder supply valve is arranged between the upper powder cylinder and the filter sieve.

A material level sensor and an oxygen content sensor are arranged in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the material level sensor can detect the powder content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the oxygen content sensor can detect the oxygen content in the powder supply device, the powder feeding cylinder and the powder collecting cylinder.

Further, the level sensor comprises an upper sensor and a lower sensor;

when the upper sensor is triggered, the powder is filled, and the powder supply is stopped;

when the lower sensor is triggered, the powder is lack, and the powder pumping is stopped.

The upper sensors are respectively arranged at the upper parts of the powder supply device, the powder feeding cylinder and the powder collecting cylinder;

the lower sensors are respectively arranged at the lower parts of the powder supply device, the upper powder cylinder and the powder collection cylinder.

As shown in fig. 6, a control method for a selective laser melting 3D printing production line includes the following steps:

(1) and starting the production line. After the production line is started, determining the number and serial number of printers executing printing tasks, and detecting the following steps: the powder supply device detects the powder content in the material preparation barrel through the material level sensor and detects the oxygen content in the device through the oxygen content sensor; the 3D printer detects the powder content in receiving a powder section of thick bamboo and last powder section of thick bamboo through level sensor, detects the inside oxygen content of printer through oxygen content sensor, detects inert gas admission pressure and the inside atmospheric pressure of printer through pressure sensor, detects the base plate temperature through temperature sensor, detects scraper, forming cylinder and send powder axle motor state, detects light path system's water-cooling machine state, detects laser instrument and shakes the mirror state. And meanwhile, a metal printing oxygen content safety value, an air inlet pressure and printer internal pressure safety value, a substrate heating temperature range, a printer internal pressure safety value and a temperature safety value are set.

(2) And starting the work of the 3D printer. On the basis of the detection result in the step 1, the following conditions are judged: the powder supply device has sufficient powder in the material preparation cylinder and the internal oxygen content is lower than the safety value of the oxygen content of metal printing; the oxygen content in the 3D printing is lower than the safety value of the oxygen content in the metal printing, the gas inlet pressure of the inert gas and the internal pressure of the printer are lower than the safety value, the temperature of the substrate is within a set range, the scraper, the forming cylinder and the powder feeding shaft motor are all normal, the water cooling machine is in a starting state, and the laser and the vibrating mirror are in a starting state. And in the case that all the conditions are met, loading the slice file of the metal part by the 3D printer and executing the 3D printing work.

(3) Powder is pumped by the powder supply device. In the printing process, the redundant powder that 3D printer produced is receiving the powder section of thick bamboo gradually and is increasing. The 3D printer detects through the upper portion sensor of receiving a powder section of thick bamboo and is being full of the powder in receiving a powder section of thick bamboo, sends and takes out powder instruction to supplying whitewashed device. The powder supply device is matched with the number of the 3D printer corresponding to the powder receiving barrel, the powder return valve corresponding to the number is opened, the first communication valve and the first circulating fan are opened, wind power generated by the fan is utilized to pump out metal powder, the filter screen is utilized to filter coarse particles, fine powder is recycled to the powder storage barrel until the lower sensor of the powder receiving barrel is triggered, the fact that the powder receiving barrel does not contain powder is shown, and the powder supply device stops powder pumping.

(4) The powder supply device supplies powder. In the printing process, metal powder in the powder feeding cylinder of the 3D printer is gradually consumed in printed parts. The 3D printer detects through the lower part sensor of last powder section of thick bamboo and is about to lack the powder in last powder section of thick bamboo, send and supply the powder instruction to supplying the powder device, the lower part sensor that works as last powder section of thick bamboo triggers, supply the powder device to match the 3D printer serial number that last powder section of thick bamboo corresponds, open the confession powder valve that the serial number corresponds, open second intercommunication valve and second circulating fan, utilize the fan to form wind-force and will supply the powder circulation that the powder device stored up in the powder section of thick bamboo to send to last powder section of thick bamboo in, the upper portion sensor that until last powder section of thick bamboo triggers, it is full of the powder to show that last powder section of thick bamboo is.

(5) The printing is completed. And (4) circularly executing the step 2, the step 3 and the step 4 by the 3D printing production line until the 3D printer completes the printing task. 3D prints and detects that internal pressure is less than and gets a pressure safety value to the base plate temperature is less than the safety value, returns the state to supplying whitewashed device, and carries out and takes out the part.

Examples

A production line consisting of 5 3D printing devices and 1 set of powder supply device is taken as an example, and the 3D printing production line with selective laser melting and the control method are concretely explained.

(1) And starting the production line. This task needs to use the printers No. 1, No. 2 and No. 3 to carry out the task, and No. 4 and No. 5 are in a space state. The following tests were performed: the powder supply device detects the powder content in the material preparation barrel through the material level sensor and detects the oxygen content in the device through the oxygen content sensor; no. 1, No. 2, No. 3D printer pass through level sensor and detect the powder content in receiving a powder section of thick bamboo and last powder section of thick bamboo, detect the inside oxygen content of printer through oxygen content sensor, detect inert gas admission pressure and the inside atmospheric pressure of printer through pressure sensor, detect the base plate temperature through temperature sensor, detect scraper, forming cylinder and powder feeding axle motor state, detect light path system's water-cooling machine state, detect laser instrument and galvanometer state.

The safety value of the oxygen content of metal printing of the equipment is 500ppm, the safety value of the air inlet pressure is 15kPa, the safety value of the internal pressure of the printer is 10kPa, the heating range of the substrate is 200-220 ℃, the safety value of the workpiece taking pressure is 200Pa, and the safety value of the temperature is 30 ℃.

(2) And starting the work of the 3D printer. On the basis of the detection result in the step 1, the following conditions are judged: the powder content in the powder storage cylinder of the powder supply device is sufficient, and the internal oxygen content is 452ppm and is lower than the printing oxygen content safety value;

the oxygen content of the No. 1 printer is 460ppm lower than the safety value of the oxygen content of metal printing, the inert gas inlet pressure is 11872Pa, the internal pressure is 7221Pa, the substrate temperature is 209 ℃, the scraper, the forming cylinder and the powder feeding shaft motor are normal, the water cooling machine is started, and the laser and the vibrating mirror are in a starting state. And when all the conditions are met, the No. 1 3D printer loads the slice file of the metal part and executes 3D printing work.

The oxygen content of No. 2 printer is 408ppm lower than the safety value of the oxygen content of metal printing, the inert gas inlet pressure of 12074Pa, the internal pressure of 8511Pa, the substrate temperature of 203 ℃, the scraper, the forming cylinder and the powder feeding shaft motor are normal, the water cooling machine is started, and the laser and the vibrating mirror are in the starting state. And if the condition is met, loading the slice file of the metal part by the No. 2 3D printer, and executing 3D printing work.

The oxygen content of the No. 3 printer is 487ppm which is lower than the safety value of the oxygen content of metal printing, the inlet pressure of inert gas is 11620Pa, the internal pressure is 7034Pa, the temperature of a substrate is 210 ℃, a scraper, a forming cylinder and a powder feeding shaft motor are normal, a water cooling machine is started, and a laser and a vibrating mirror are in a starting state. And if the condition is met, loading the slice file of the metal part by the 3D printer and executing the 3D printing work.

(3) Powder is pumped and recovered by the powder supply device. In the printing process, the redundant powder that 3D printer produced is receiving the powder section of thick bamboo gradually and is increasing. When an upper sensor of the powder collecting barrel is triggered, the powder supply device is matched with a 3D printer number corresponding to the powder collecting barrel, a powder return valve corresponding to the number is opened, the first communication valve and the first circulating fan are opened, wind power is formed by the fans to pump out metal powder, the filter sieve is used for filtering coarse particles, fine powder is recycled into the powder storage barrel until a lower sensor of the powder collecting barrel is triggered, the fact that the powder collecting barrel is free of powder is indicated, and the powder supply device stops powder pumping.

(4) The powder supply device supplies powder. In the printing process, metal powder in the powder feeding cylinder of the 3D printer is gradually consumed in printed parts. When the lower sensor of last powder section of thick bamboo triggers, supply the powder device to match the 3D printer number that the powder section of thick bamboo corresponds, open the powder valve that supplies that the number corresponds, open second intercommunication valve and second circulating fan, utilize the fan to form wind-force and circulate the metal powder that supplies in the powder device stores up the powder section of thick bamboo and send to the powder section of thick bamboo in, the upper sensor that reaches the powder section of thick bamboo triggers until, shows to be full of the powder in the last powder section of thick bamboo this moment, supplies the powder device to stop supplying powder.

(5) The printing is completed. And (4) circularly executing the step 2, the step 3 and the step 4 by the 3D printing production line until the 3D printer completes the printing task. After printing is completed, the state of 3 printers is realized after pressure relief and cooling:

the internal pressure of the No. 1 printer is 21Pa, the substrate temperature is 22 ℃, the part taking condition is met, and the part is successfully taken out;

the internal pressure of the No. 2 printer is 33Pa, the substrate temperature is 22 ℃, the part taking condition is met, and the part is successfully taken out;

the internal pressure of the No. 3 printer is 20Pa, the substrate temperature is 22 ℃, the workpiece taking condition is met, and the part is successfully taken out.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other like elements in a process, method, article, or apparatus that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

While the present invention has been described with reference to the embodiments shown in the drawings, the present invention is not limited to the embodiments, which are illustrative and not restrictive, and it will be apparent to those skilled in the art that various changes and modifications can be made therein without departing from the spirit and scope of the invention as defined in the appended claims.