CN109365815B

CN109365815B - Selective laser melting forming equipment

Info

Publication number: CN109365815B
Application number: CN201811581712.1A
Authority: CN
Inventors: 刘旭东; 王海涛; 邱生祥; 巩水利; 孙年俊; 谭永生; 黎明; 李初晔; 冯长征; 李中凯
Original assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Current assignee: AVIC Beijing Aeronautical Manufacturing Technology Research Institute
Priority date: 2018-12-24
Filing date: 2018-12-24
Publication date: 2021-06-08
Anticipated expiration: 2038-12-24
Also published as: CN109365815A

Abstract

The invention relates to selective laser melting forming equipment. The apparatus at least comprises: the two-dimensional moving device, the forming working platform, the forming cabin, the auxiliary cabin, the powder spreading device, the powder feeding device, the residual powder recovery device and the laser printer are arranged on two sides of the equipment main body respectively, the two-dimensional moving device is connected with and can drive the forming working platform to move between the forming cabin and the auxiliary cabin, wherein the two-dimensional moving device comprises a longitudinal driving unit for driving the forming workbench to move in the longitudinal direction and a transverse driving unit for driving the forming workbench to move transversely, under the sealed state of the forming cabin, the laser printer melts and forms the metal powder on the forming workbench into a preset part, the residual powder recovery device is used for recovering redundant metal powder, the two-dimensional moving mechanism drives the forming workbench to move from the forming cabin to the auxiliary cabin, and the auxiliary cabin is provided with an object taking window used for taking away the part on the forming workbench.

Description

Selective laser melting forming equipment

Technical Field

The invention relates to the technical field of additive manufacturing equipment, in particular to selective laser melting forming equipment.

Background

At present, the machinable metal parts of domestic SLM equipment are small in specification and light in weight, and can be directly taken out of a forming cabin after forming.

With the development of the selective laser melting technology, how to make larger parts by using the selective laser melting technology needs to be explored, the requirements on the large-scale and precision of equipment are higher and higher, the existing equipment type restricts the development of the specification and precision of the parts to be processed, and a new equipment structure type needs to be developed to meet the requirements of the selective laser melting technology.

Along with the increase of the size specification of the machinable part, the formed part is taken out, how the flatness of the formed working table is guaranteed after the size of the formed working table is increased, how the straightness of the formed working table and the perpendicularity of the formed working table meet the requirements of selective laser melting after the lifting stroke is increased, the existing main structure of the equipment is difficult to meet the requirements, and a new thought and a new main structure form are needed to be constructed to solve the problems.

Accordingly, the inventors provide a selective laser melting and forming apparatus.

Disclosure of Invention

The embodiment of the invention provides selective laser melting forming equipment, which can be used for placing and taking parts in different cabins for operation in a forming process along with the movement of a forming workbench between a forming cabin and an auxiliary cabin, ensuring accurate and reliable movement and meeting the requirement of processing parts with large sizes.

An embodiment of the present invention provides a selective laser melting and forming apparatus, including: the device comprises a two-dimensional moving device, a forming workbench (11), a forming cabin (3), an auxiliary cabin (7), a powder laying device (4), a powder feeding device (5), a residual powder recovery device (6) and a laser printer (20), wherein the laser printer (20) is arranged at the top of the forming cabin (3), the forming cabin (3) and the auxiliary cabin (7) are respectively arranged at two sides of a device main body, the two-dimensional moving device is connected with and can drive the forming workbench (11) to move between the forming cabin (3) and the auxiliary cabin (7), the two-dimensional moving device comprises a longitudinal driving unit (2) for driving the forming workbench (11) to move longitudinally and a transverse driving unit (1) for driving the forming workbench (11) to move transversely, and the powder feeding device (5) is used for conveying metal powder, the powder paving device (4) is used for paving conveyed metal powder on the forming workbench (11), the laser printer (20) is used for melting and forming the metal powder on the forming workbench (11) into a preset part under the sealing state of the forming cabin (3), the residual powder recovery device (6) is used for recovering redundant metal powder, the two-dimensional moving mechanism drives the forming workbench (11) to move from the forming cabin (3) to the auxiliary cabin (7), and the auxiliary cabin (7) is provided with an fetching window for taking away the part on the forming workbench (11).

Further, still include left base (8) and right base (9), horizontal drive unit (1) includes actuating mechanism and left guide rail group and right guide rail group, establish through left guide rail group and right guide rail group shaping workstation (11) the upper portion of left base and right base, actuating mechanism drive left guide rail group and right guide rail group synchronous motion drive shaping workstation (11) are in remove between shaping cabin (3) and auxiliary cabin (7).

Further, the longitudinal driving unit (2) comprises a forming seal box (13), a lifting ram support (14), a motor arranged in the power transmission direction, a speed reducer (17), a first ball screw (16) and a lifting ram (12), the top end of the lifting ram (12) is connected with the forming workbench (11), four linear guide rails (15) are arranged between the lifting ram (12) and the lifting ram support (14) in a rectangular symmetry manner, the forming seal boxes (13) are arranged at the periphery of the four linear guide rails (15), the top of the forming seal box (13) is used for supporting the forming workbench (11), in the power transmission direction, the motor drives the reducer (17) to drive the first ball screw (16), used for driving the lifting ram (12) to move up and down along the vertical direction of the four linear guide rails (15), thereby driving the forming workbench (11) to do lifting motion in the forming seal box (13).

Further, the longitudinal drive unit further comprises an encoder (18) for feeding back the displacement of the forming table (11) in the vertical direction.

Further, the forming cabin (3) is a box structure comprising cabin doors of corresponding side plates and top plates, and the forming workbench (11) moves to the bottom of the forming cabin (3) along with the forming seal box (13) during forming operation, and the forming seal box (13) and the forming cabin (3) form a sealed cabin.

Furthermore, a first observation window (19) of the laser safety protection glass is arranged on a side plate of the forming cabin (3), the processing condition inside the forming cabin (3) is observed in real time, and two sets of laser printers (20) are installed on a top plate of the forming cabin (3).

Further, spread powder device (4) including spreading powder scraper blade (21), drive arrangement (22), detection switch (24) of scraper guide rail (23), drive arrangement (22) are used for driving powder dusting scraper blade (21) are followed scraper guide rail (23) and are moved, spread the powder, detection switch (24) are used for detecting two extreme position of spreading powder scraper blade (21), send the signal that targets in place.

Furthermore, the powder feeding device (5) comprises a powder support plate (25), a linear motion assembly (26), a powder feeding sealed box body (28), a bracket (29), a motor (30) and a second ball screw (27) which are arranged in the power transmission direction, the bracket (29) is arranged at the periphery of the motor (30), the powder feeding sealing box body (28) is arranged at the periphery of the linear motion component (26) at the upper part of the bracket (29), the linear motion assemblies (26) are arranged on two sides of the second ball screw (27), in the power transmission direction, the motor (30) drives the second ball screw (27) and the powder support plate (25) to pass through the linear motion assembly (26), quantitative powder is conveyed to the front of the powder spreading scraper (21), and the powder is spread on a part backing plate of the forming workbench (11) by the powder spreading scraper (21).

Further, surplus powder recovery unit (6) are used for retrieving the surplus powder after the deposit, surplus powder recovery unit (6) include powder collection funnel (31), storage case (32) that from the top down set up.

Furthermore, the auxiliary cabin (7) is of a box structure comprising a cabin door (33) with a corresponding side plate and a corresponding top plate, when the forming workbench (11) moves to the bottom of the auxiliary cabin (7) along with the forming seal box (13), the forming seal box (13) and the auxiliary cabin (7) form a sealed cabin, a second observation window (34) is arranged on the side plate of the auxiliary cabin (7), and an integrated sealing glove (35) is arranged below the second observation window (34) and used for manually operating the cabin under the protection of inert gas.

In conclusion, the beneficial effects of the invention are as follows:

1. the work of part forming, part pretreatment and workpiece taking out after forming is finished respectively by adopting a forming station and an auxiliary station, so that the problems of adjustment of a base plate before forming of a large metal part and difficulty in taking out of the formed part in a forming chamber are solved;

2. the longitudinal driving unit for driving the forming workbench to move up and down is guided by four linear guide rails which are arranged in a rectangular symmetrical mode, and the center-of-gravity driving mode of the middle first ball screw is driven by the motor, so that the asymmetric deformation generated by load change along with the forming height change of the part in the forming process is greatly reduced, the straightness of the forming workbench moving up and down and the perpendicularity of the forming workbench surface after the lifting stroke is increased are improved, the stability of the flatness of the workbench surface in the forming process is ensured, and the forming precision of metal parts is improved;

3. the redundant powder can be taken out under the relatively closed condition by utilizing the auxiliary cabin at the auxiliary station, so that the convenience and the safety of powder taking are improved;

4. because the auxiliary station is adopted, the volume of the forming cabin is greatly reduced, the air washing speed of the forming cabin is accelerated, and the forming efficiency of workpieces is improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1a, fig. 1b and fig. 1c are schematic side views of the general structure of a selective laser melting and forming apparatus according to an embodiment of the present invention.

Fig. 2 is a schematic view of a lateral drive unit of an embodiment of the present invention.

Fig. 3a and 3b are schematic views of a longitudinal driving unit of an embodiment of the present invention.

FIG. 4 is a schematic view of a shaped cabin of an embodiment of the present invention.

Fig. 5 is a schematic view of a powder laying apparatus according to an embodiment of the present invention.

FIG. 6 is a schematic view of a powder feeding apparatus according to an embodiment of the present invention.

Fig. 7 is a schematic view of a remaining powder recovering apparatus according to an embodiment of the present invention.

Fig. 8 is a schematic view of an auxiliary chamber according to an embodiment of the present invention.

In the figure:

1-a transverse drive unit; 2-a longitudinal drive unit; 3-forming the chamber; 4-a powder spreading device; 5-powder feeding device; 6-residual powder recovery device; 7-an auxiliary compartment; 8-a left base; 9-right base; 10-a transverse moving guide; 11-a forming table; 12-lifting ram; 13-forming a sealed box; 14-lifting ram support; 15-linear guide rail; 16-a first ball screw; 17-a reducer; 18-an encoder; 19-a first viewing window; 20-a laser printer; 21-spreading powder scraper; 22-a drive device; 23-a squeegee guide rail; 24-a detection switch; 25-powder support plate; 26-a linear motion assembly; 27-a second ball screw; 28-powder feeding sealing box body; 29-a scaffold; 30-a motor; 31-powder collecting funnel; 32-a material storage box; 33-a hatch door; 34-a second viewing window; 35-sealed glove.

Detailed Description

The embodiments of the present invention will be described in further detail with reference to the drawings and examples. The following detailed description of the embodiments and the accompanying drawings are provided to illustrate the principles of the invention and are not intended to limit the scope of the invention, i.e., the invention is not limited to the embodiments described, but covers any modifications, alterations, and improvements in the parts, components, and connections without departing from the spirit of the invention.

It should be noted that the embodiments and features of the embodiments in the present application may be combined with each other without conflict. The present application will be described in detail below with reference to the embodiments with reference to the attached drawings.

Along with the increase of the size specification of the machinable part, the formed part is taken out, the flatness of the formed working table is guaranteed after the size of the formed working table is increased, the straightness and the perpendicularity of the formed part and the working table meet the requirements of selective laser melting after the lifting stroke is increased, and the existing main structure of the equipment is difficult to meet the requirements. The inventor therefore provides the following general structure of a selective laser melting and forming apparatus to solve the problems of the prior art.

Fig. 1a, fig. 1b and fig. 1c are schematic side views of the general structure of a selective laser melting and forming apparatus according to an embodiment of the present invention. As shown in FIG. 1, the apparatus comprises at least two-dimensional moving means (comprising a transverse driving unit 1 and a longitudinal driving unit 2), a forming table 11, a forming chamber 3, an auxiliary chamber 7, a powder spreading device 4, a powder feeding device 5, a residual powder recovering device 6 and a laser printer 20, wherein the laser printer 20 is arranged on the top of the forming chamber 3, the forming chamber 3 and the auxiliary chamber 7 are respectively arranged on two sides of the apparatus main body, the two-dimensional moving means is connected with and can drive the forming table 11 to move between the forming chamber 3 and the auxiliary chamber 7, wherein the two-dimensional moving means comprises a longitudinal driving unit 2 for driving the forming table 11 to move in the longitudinal direction and a transverse driving unit 1 for driving the forming table 11 to move transversely, the powder feeding device 5 is used for conveying metal powder, the powder spreading device 4 is used for spreading the conveyed metal powder on the forming workbench 11, the laser printer 20 is used for melting and forming the metal powder on the forming workbench 11 into a preset part in a sealed state of the forming cabin 3, the residual powder recovery device 6 is used for recovering redundant metal powder, the two-dimensional moving mechanism drives the forming workbench 11 to move from the forming cabin 3 to the auxiliary cabin 7, and the auxiliary cabin 7 is provided with a fetching window for fetching the part on the forming workbench 11.

Note that the lateral direction in the lateral drive unit 1 in the present embodiment is the horizontal moving direction with respect to the apparatus main body, and the longitudinal direction in the longitudinal drive unit 2 is the vertical lifting moving direction with respect to the apparatus main body.

From the above, the main structure of the apparatus is provided with two compartments, one being the shaping compartment 3 and one being the auxiliary compartment 7. The forming table 11 has two positions, and the forming table 11 can be moved to the forming chamber 3 by the transverse driving unit 1 and the longitudinal driving unit 2 to form a workpiece, or can be moved to the auxiliary chamber 7 to perform pretreatment and forming of a part and then take out the workpiece.

The transverse driving unit 1 is shown in fig. 2, and in addition, the apparatus of the present invention further includes a left base 8 and a right base 9, specifically, the transverse driving unit 1 includes a driving mechanism and a left guide rail set and a right guide rail set (including a transverse moving guide rail 10) corresponding to the left base 8 and the right base 9, the forming table 11 is erected on the upper portions of the left base 8 and the right base 9 through the left guide rail set and the right guide rail set, and the driving mechanism drives the left guide rail set and the right guide rail set to move synchronously, so as to drive the forming table 11 to move between the forming cabin 3 and the auxiliary cabin 7.

Longitudinal drive unit 2 referring to fig. 3a and 3b, the longitudinal drive unit 2 includes a forming seal box 13, a lift ram support 14, and a motor, a speed reducer 17, a first ball screw 16, and a lift ram 12 provided in a power transmission direction, the top end of the lifting ram 12 is connected with the forming workbench 11, four linear guide rails 15 are symmetrically arranged between the lifting ram 12 and the lifting ram support 14 in a rectangular shape (see figure 3b), the forming seal box 13 is arranged at the periphery of the four linear guide rails 15, the top of the forming seal box 13 is used for supporting the forming workbench 11, in the power transmission direction, the motor drives the reducer 17 to drive the first ball screw 16 for driving the lifting ram 12 to move up and down along the vertical direction of the four linear guide rails 15, so as to drive the forming workbench 11 to move up and down in the forming seal box 13. The longitudinal drive unit further comprises an encoder 18 for feeding back the displacement of the forming table 11 in the vertical direction.

Because the stroke of the lifting motion is long, the load is large, the heating is needed, a gravity center driving mode is adopted, the four linear guide rails 15 are arranged in a rectangular symmetrical mode, the ball screw 16 acts on the symmetrical center (gravity center), and when the lifting motion is carried out in the forming process, the load is uniform, and the asymmetric deformation of the guide rails is eliminated to the maximum extent. The forming worktable 11 is driven by the forming seal box 13 to accurately and reliably move up and down.

The forming chamber 3, which is shown with reference to fig. 4, effects the forming of the workpiece. The forming chamber 3 is a box structure comprising side and top panels, and during the forming operation, the forming workbench 11 moves to the bottom of the forming chamber 3 along with the forming seal box 13, and the forming seal box 13 and the forming chamber 3 form a sealed chamber. In addition, the side plate of the forming cabin 3 is provided with a first observation window 19 of laser safety protection glass, the processing condition in the forming cabin 3 can be observed in real time through the first observation window, and two sets of the laser printers 20 are installed on the top plate of the forming cabin 3. In particular, the box frame of the shaping chamber 3 can be made with a combined or welded mechanism, the shaping chamber 3 operating under inert gas protection. Two sets of laser printers 20 may employ two sets of laser polarizers located outside the ceiling of the forming chamber 3.

The powder laying device 4 is shown in fig. 5, and achieves the laying of powder in the forming process. Spread powder device 4 including spreading powder scraper blade 21, drive arrangement 22, scraper guide 23's detection switch 24, drive arrangement 22 is used for the drive powder dusting scraper blade 21 moves along scraper guide 23, spreads the powder, detection switch 24 is used for detecting two extreme position of spreading powder scraper blade 21, sends the signal that targets in place.

The powder feeding device 5, as shown in fig. 6, achieves the conveyance of the metal powder required for forming. The powder feeding device 5 comprises a powder support plate 25, a linear motion assembly 26, a powder feeding seal box 28, a bracket 29, and a motor 30 and a second ball screw 27 which are arranged in the power transmission direction, wherein the bracket 29 is arranged at the periphery of the motor 30, the powder feeding seal box 28 is arranged at the periphery of the linear motion assembly 26 at the upper part of the bracket 29, the linear motion assembly 26 is arranged at two sides of the second ball screw 27, in the power transmission direction, the motor 30 drives the second ball screw 27 and the powder support plate 25 to pass through the linear motion assembly 26, so that quantitative powder is fed to the front of the powder spreading scraper 21, and the powder spreading scraper 21 spreads the powder on a part backing plate of the forming workbench 11.

The residual powder recovery device 6 is shown in fig. 7, and realizes recovery of residual powder after powder laying. The residual powder recovery device 6 is used for recovering the laid residual powder, and the residual powder recovery device 6 comprises a powder collecting funnel 31 and a storage box 32 which are arranged from top to bottom.

Auxiliary chamber 7 referring to fig. 8, the excess powder is recovered and the work piece is removed after the chamber has been pre-treated and formed. The auxiliary cabin 7 is a box structure including a cabin door 33 with corresponding side plate and top plate, the frame of the box structure can adopt a combined or welded structure, when the forming workbench 11 moves to the bottom of the auxiliary cabin 7 along with the forming seal box 13, the forming seal box 13 and the auxiliary cabin 7 form a sealed cabin, a second observation window 34 is arranged on the side plate of the auxiliary cabin 7, and an integrated sealing glove 35 is arranged below the second observation window 34 and used for carrying out manual operation in the cabin under the protection of inert gas.

It should be clear that the embodiments in this specification are described in a progressive manner, and the same or similar parts in the embodiments are referred to each other, and each embodiment focuses on the differences from the other embodiments. For embodiments of the method, reference is made to the description of the apparatus embodiments in part. The present invention is not limited to the specific steps and structures described above and shown in the drawings. Also, a detailed description of known process techniques is omitted herein for the sake of brevity.

The above description is only an example of the present application and is not limited to the present application. Various modifications and alterations to this application will become apparent to those skilled in the art without departing from the scope of this invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application should be included in the scope of the claims of the present application.

Claims

1. A selective laser melting and forming apparatus, comprising: the device comprises a two-dimensional moving device, a forming workbench (11), a forming cabin (3), an auxiliary cabin (7), a powder laying device (4), a powder feeding device (5), a residual powder recovery device (6) and a laser printer (20), wherein the laser printer (20) is arranged at the top of the forming cabin (3), the forming cabin (3) and the auxiliary cabin (7) are respectively arranged at two sides of a device main body, the two-dimensional moving device is connected with and can drive the forming workbench (11) to move between the forming cabin (3) and the auxiliary cabin (7), the two-dimensional moving device comprises a longitudinal driving unit (2) for driving the forming workbench (11) to move longitudinally and a transverse driving unit (1) for driving the forming workbench (11) to move transversely, and the powder feeding device (5) is used for conveying metal powder, the powder paving device (4) is used for paving conveyed metal powder on the forming workbench (11), the laser printer (20) is used for melting and forming the metal powder on the forming workbench (11) into a preset part under the sealing state of the forming cabin (3), the residual powder recovery device (6) is used for recovering redundant metal powder, the two-dimensional moving device drives the forming workbench (11) to move from the forming cabin (3) to the auxiliary cabin (7), and the auxiliary cabin (7) is provided with an fetching window for taking away the part on the forming workbench (11).

2. The selective laser melting and forming equipment according to claim 1, further comprising a left base (8) and a right base (9), wherein the transverse driving unit (1) comprises a driving mechanism and a left guide rail set and a right guide rail set, the forming workbench (11) is erected on the upper portions of the left base and the right base through the left guide rail set and the right guide rail set, and the driving mechanism drives the left guide rail set and the right guide rail set to move synchronously to drive the forming workbench (11) to move between the forming cabin (3) and the auxiliary cabin (7).

3. The selective laser melting and forming device according to claim 1, wherein the longitudinal driving unit (2) comprises a forming seal box (13), a lifting ram support (14), and a motor, a reducer (17), a first ball screw (16) and a lifting ram (12) which are arranged in a power transmission direction, the top end of the lifting ram (12) is connected with the forming workbench (11), four linear guide rails (15) are arranged between the lifting ram (12) and the lifting ram support (14) in a rectangular symmetry manner, the forming seal box (13) is arranged at the periphery of the four linear guide rails (15), the top of the forming seal box (13) is used for supporting the forming workbench (11), in the power transmission direction, the motor drives the reducer (17) to drive the first ball screw (16) for driving the lifting ram (12) to move vertically along the four linear guide rails (15), thereby driving the forming workbench (11) to do lifting motion in the forming seal box (13).

4. The selective laser melting forming apparatus according to claim 3, wherein the longitudinal driving unit further comprises an encoder (18) for feeding back a displacement of the forming table (11) in a vertical direction.

5. A selective laser melting and forming apparatus according to claim 3, characterized in that the forming chamber (3) is a box structure comprising side, ceiling doors, the forming table (11) moving with the forming seal box (13) to the bottom of the forming chamber (3) during the forming operation, the forming seal box (13) forming a sealed chamber with the forming chamber (3).

6. The selective laser melting and forming equipment according to claim 5, wherein a first observation window (19) of laser safety glass is arranged on a side plate of the forming chamber (3) to observe the processing condition inside the forming chamber (3) in real time, and two sets of the laser printers (20) are arranged on the top plate of the forming chamber (3).

7. The selective laser melting and forming equipment according to claim 3, wherein the powder spreading device (4) comprises a powder spreading scraper (21), a driving device (22) and a detection switch (24) of a scraper guide rail (23), the driving device (22) is used for driving the powder spreading scraper (21) to move along the scraper guide rail (23) for spreading powder, and the detection switch (24) is used for detecting two limit positions of the powder spreading scraper (21) and sending a position signal.

8. The selective laser melting and forming apparatus according to claim 7, wherein the powder feeder (5) comprises a powder support plate (25), a linear motion assembly (26), a powder feeding seal box (28), a bracket (29), and a motor (30) and a second ball screw (27) arranged in a power transmission direction, the bracket (29) is arranged at the periphery of the motor (30), the powder feeding seal box (28) is arranged at the periphery of the linear motion assembly (26) at the upper part of the bracket (29), the linear motion assembly (26) is arranged at both sides of the second ball screw (27), the motor (30) drives the second ball screw (27) together with the powder support plate (25) to feed a fixed amount of powder to the front of the powder spreading scraper (21) via the linear motion assembly (26) in the power transmission direction, the powder is spread on a part backing plate of a forming workbench (11) by a powder spreading scraper (21).

9. The selective laser melting and forming equipment according to claim 8, wherein the residual powder recovery device (6) is used for recovering the laid excessive powder, and the residual powder recovery device (6) comprises a powder collecting hopper (31) and a storage box (32) which are arranged from top to bottom.

10. The selective laser melting and forming equipment according to any one of claims 3 to 9, wherein the auxiliary chamber (7) is a box structure comprising a side-plate and top-plate chamber door (33), the forming seal box (13) and the auxiliary chamber (7) form a sealed chamber when the forming workbench (11) moves to the bottom of the auxiliary chamber (7) along with the forming seal box (13), a second observation window (34) is arranged on the side plate of the auxiliary chamber (7), and an integrated sealing glove (35) is arranged below the second observation window (34) and used for manual operation in the chamber under the protection of inert gas.