CN219052918U

CN219052918U - Frame structure of large-scale metal 3D printing equipment

Info

Publication number: CN219052918U
Application number: CN202223322882.2U
Authority: CN
Inventors: 赵太传; 刘鑫炎; 潘良明
Original assignee: Hunan Farsoon High Tech Co Ltd
Current assignee: Hunan Farsoon High Tech Co Ltd
Priority date: 2022-12-12
Filing date: 2022-12-12
Publication date: 2023-05-23
Anticipated expiration: 2032-12-12

Abstract

The utility model provides a rack structure of large-scale metal 3D printing equipment, which comprises a bearing underframe, wherein a pedal for passing, a powder cleaning support for a powder cleaning cavity and accessory equipment for powder cleaning, a cavity supporting support for printing cavity installation and an auxiliary support are sequentially arranged above the bearing underframe from one end to the other end, and the auxiliary support is used for installation of a laser and an equipment host; a plurality of adjustable feet for supporting and leveling the bearing underframe are arranged below the bearing underframe; the middle of bearing chassis top is installed cylinder body transfer platform and maintenance moving platform from one end to the other end in proper order. The utility model adopts a modularized design to modularly integrate each component on the frame structure, has good universality and module expansibility, can be flexibly adjusted according to the change of the size parameters of equipment, and is convenient to use.

Description

Frame structure of large-scale metal 3D printing equipment

Technical Field

The utility model belongs to the technical field of additive manufacturing, and particularly relates to a frame structure of large-scale metal 3D printing equipment.

Background

The additive manufacturing technology (Additive Manufacturing, abbreviated as AM) is an advanced manufacturing technology with the distinct characteristics of digital manufacturing, high flexibility and adaptability, direct CAD model driving, rapidness, rich and various material types and the like, and has become a support technology in the modern advanced manufacturing technology since the last development of the eighties of the twentieth century. Selective laser melting (Metal Laser Sintering, abbreviated as MLS) is one of the most rapidly developed additive manufacturing technologies in recent years, which uses metal materials as raw materials, adopts laser to scan the cross section of a three-dimensional entity layer by layer to finish prototype manufacturing, is not limited by the complexity of the shape of a part, does not need any tooling die, and has wide application range.

The existing metal 3D printing equipment mainly comprises a frame, a printing cavity, an equipment host, a laser, a powder supply and feeding system, a forming cylinder, a cylinder body transferring mechanism, an electric cabinet, a gas and water cooling pipeline system, an air pipe system, a powder cleaning device, a dust smoke filtering system, a powder overflow recycling system, a control system and the like. How to assemble the components together according to performance requirements, and achieving good effects on rationality, convenience and economy puts forward high requirements on the frame structure of large-scale metal 3D printing equipment, and plays a very critical role in the performance of the equipment. Therefore, the utility model designs the frame structure of the large-scale metal 3D printing equipment, adopts the modularized design, so that all components can be integrated on the frame structure in a modularized manner, and the frame structure has good universality and module expansibility, can be flexibly adjusted according to the change of equipment size parameters, and is convenient to use.

Disclosure of Invention

The utility model aims to provide a frame structure of large-scale metal 3D printing equipment, which adopts a modularized design, so that all components can be integrated on the frame structure in a modularized manner, and the frame structure has good universality and module expansibility, can be flexibly adjusted according to the change of equipment size parameters, and is convenient to use.

In order to achieve the above purpose, the utility model provides a rack structure of large-scale metal 3D printing equipment, which comprises a bearing underframe, wherein a pedal table for passing, a powder cleaning support for installing a powder cleaning cavity and accessory equipment for cleaning, a cavity supporting support for installing a printing cavity and an auxiliary support are sequentially arranged above the bearing underframe from one end to the other end, and the auxiliary support is used for installing a laser and an equipment host; a plurality of adjustable feet used for supporting and leveling the bearing underframe are arranged below the bearing underframe.

The middle of bearing chassis top is installed cylinder body from one end to the other end in proper order and is transported the platform and overhaul the moving platform, cylinder body is transported the platform and can be followed with overhaul the moving platform bearing chassis axial displacement, step on platform, clear powder support and cavity support bracket cover the cylinder body is transported the platform, cavity support bracket and auxiliary stand cover overhaul the moving platform.

Further, the adjustable ground comprises a heavy-load adjustable ground; the heavy-load adjustable foundation comprises a first foot seat, a first screw rod, a first nut and a nut pad, wherein the first foot seat is in spherical hinge connection with the lower end of the first screw rod, two first nuts are arranged on the first screw rod, and the nut pad is further arranged above the two first nuts by the first screw rod.

The first nut positioned below and the first screw rod are fixed into an integrated structure, and the nut pad and the first nut positioned above can move on the first screw rod in a threaded manner; the upper end of the first screw rod is in threaded connection with the bearing underframe, and the nut pad is connected with the bearing underframe through a fastener.

Further, the adjustable anchor further comprises a common adjustable anchor, the common adjustable anchor comprises a second base, a second screw rod and a second nut, the second base is fixedly connected with the lower end of the second screw rod, two second nuts are installed on the second screw rod, the second nuts located below and the second screw rod are fixed into an integral structure, the second nuts located above can move in a threaded mode relative to the second screw rod, and the upper end of the second screw rod is in threaded connection with the bearing underframe.

Further, the first nut is matched with the first screw rod through ladder-shaped threads, and the nut pad is matched with the first screw rod through ladder-shaped threads.

Further, a spherical groove is formed in the first foot seat, and a ball head matched with the spherical groove is arranged at the lower end of the first screw rod.

Further, the cylinder body transfer platform comprises a transfer platform body and a first movable driving mechanism, and the transfer platform body is movably arranged on the bearing underframe through a guide rail and guide groove structure; the first moving driving mechanism is connected with the transferring platform body and used for driving the transferring platform body to axially move relative to the bearing underframe.

Further, overhaul moving platform includes maintenance frame, maintenance platform body, second remove actuating mechanism and lift actuating mechanism, maintenance frame pass through guide rail guide slot structure remove install in on the bearing chassis, maintenance platform body pass through lift actuating mechanism install in on the maintenance frame, lift actuating mechanism is used for the drive maintenance platform body goes up and down, second remove actuating mechanism with maintenance frame is connected and is used for the drive maintenance frame for bearing chassis axial displacement.

Further, the maintenance mobile platform further comprises a tool rack arranged on the table top of the maintenance platform body.

Further, the lifting driving mechanism adopts a scissor type lifting platform.

Further, the pedal table is of a fixed structure; or the pedal table is in a turnover structure and comprises a pedal table frame, a turning plate and an electric push rod, wherein the pedal table frame is fixedly arranged on the bearing bottom frame, the turning plate is positioned in the middle of the pedal table surface, and the turning plate is rotationally connected with the pedal table frame; the fixed end of the electric push rod is rotationally connected with the bearing underframe, and the telescopic end is rotationally connected with the turning plate.

The utility model has the beneficial effects that: the bearing underframe is used for the integral bearing of equipment, has strong structural rigidity, adopts a plurality of adjustable feet for supporting and leveling, has simple supporting mode and convenient leveling, and has low requirement on the foundation ground during use. The pedal is convenient for operating personnel to pass through the rack structure, especially when clear powder station, pedal has made things convenient for operating personnel to stand work in clear powder chamber periphery, provides safe and reliable's protection and support for operating personnel. The powder cleaning bracket is used for installing a powder cleaning cavity and auxiliary equipment for cleaning powder. The cavity supporting bracket is used for installing a printing cavity, has good structural rigidity, is a core station of the metal 3D printing equipment, and is a place where the equipment prints a workpiece. The auxiliary bracket is used for mounting the laser and the device host, and the main mounting part listed above is the auxiliary bracket, and can be used for integrally mounting other components included in the metal 3D printing device. The cylinder body transfer platform is used for transferring the forming cylinder, so that the forming cylinder can accurately and flexibly move and position at stations of printing, powder cleaning, workpiece taking and the like, and a good expansion space is provided for production line arrangement. The maintenance preparation and the cleaning of equipment before and after printing are facilitated for operators through the overhaul mobile platform, so that the maintenance is simple and convenient, safe and reliable. The utility model adopts a modularized design, so that each component can be integrated on a frame structure in a modularized way, has good universality and module expansibility, can be flexibly adjusted according to the change of equipment size parameters, and is convenient to use. Meanwhile, the frame structure of the utility model is easy to manufacture, simple to assemble and convenient to maintain in the later period.

Drawings

In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings that are required in the embodiments or the description of the prior art will be briefly described, it being obvious that the drawings in the following description are only some embodiments of the utility model, and that other drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic diagram of the structure of the present utility model;

FIG. 2 is a perspective view of the assembled load-bearing chassis, cylinder transfer platform and service mobile platform of the present utility model;

FIG. 3 is a perspective view of the pedal of the present utility model;

fig. 4 is a perspective view of the pedal of the present utility model, wherein the turning plate is turned upwards.

FIG. 5 is a perspective view of the service mobile platform of the present utility model;

FIG. 6 is an enlarged view at A in FIG. 5;

FIG. 7 is a perspective view of a heavy duty adjustable anchor of the present utility model;

FIG. 8 is a schematic cross-sectional view of FIG. 7;

FIG. 9 is a perspective view of a conventional adjustable anchor according to the present utility model.

The above reference numerals:

the device comprises a bearing chassis, a pedal platform, a powder cleaning support, a cylinder body transferring platform, a cavity supporting support, a maintenance moving platform, an auxiliary support, an 8-adjustable foot support, an electric cabinet, a guide rail, a cylinder body transferring platform, a 41 first moving driving mechanism, a pedal platform, a 202 turning plate, a 203 electric push rod, a 60 maintenance frame, a 61 maintenance platform body, a 62 second moving driving mechanism, a 620 motor, a 621 speed reducer, a 622 driving gear, a 600 guide groove, a 63 tool frame, an 80-weight-load-adjustable foot support, a 801 first foot support, a 802 first screw, a 803 first nut, a 804 nut pad, a 8010 spherical groove, a 8020 ball head, a 81 common-adjustable foot support, a 810 second foot support, a 811 second screw and a 812 second nut.

Detailed Description

In order that the utility model may be readily understood, a more complete description of the utility model will be rendered by reference to the appended drawings. Preferred embodiments of the present utility model are shown in the drawings. This utility model may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.

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

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

Where the terms "comprising," "having," and "including" are used herein, another component may also be added unless explicitly defined as such, e.g., "consisting of … …," etc. Unless mentioned to the contrary, singular terms may include plural and are not to be construed as being one in number.

It will be further understood that when interpreting an element, although not explicitly described, the element is intended to include the range of errors which should be within the acceptable limits of deviation from the particular values identified by those skilled in the art. For example, "about," "approximately," or "substantially" may mean within one or more standard deviations, and is not limited herein.

Examples

As shown in fig. 1 and 2, the rack structure of a large-scale metal 3D printing apparatus provided in this embodiment includes a bearing chassis 1, a tread table 2 for passing, a powder cleaning support 3 for cleaning a powder cavity and accessory equipment for cleaning powder, a cavity supporting support 5 for mounting a printing cavity, and an auxiliary support 7 are sequentially mounted from one end to the other end above the bearing chassis 1, and the auxiliary support 7 is used for mounting a laser and an apparatus host; a plurality of adjustable feet 8 for supporting and leveling the bearing underframe 1 are arranged below the bearing underframe 1. As shown in fig. 1, the cavity support bracket 5 and the auxiliary bracket 7 are respectively framed with a dashed line frame.

The middle of the upper part of the bearing chassis 1 is provided with a cylinder body transferring platform 4 and an overhaul moving platform 6 from one end to the other end in sequence, the cylinder body transferring platform 4 and the overhaul moving platform 6 can axially move along the bearing chassis 1, the cylinder body transferring platform 4 is covered by the pedal 2, the powder cleaning support 3 and the cavity supporting support 5, and the overhaul moving platform 6 is covered by the cavity supporting support 5 and the auxiliary support 7.

In the embodiment, the bearing underframe 1 is used for the integral bearing of equipment, has strong structural rigidity, adopts a plurality of adjustable feet 8 for supporting and leveling, has simple supporting mode and convenient leveling, and has low requirement on the foundation ground during use. Wherein, the bearing underframe 1 is manufactured by welding profile steel, and the bearing part is a large-size thick-wall rectangular profile steel. As shown in fig. 1, an electric cabinet 9 is installed in the other end of the bearing chassis 1.

The pedal 2 facilitates the operation staff to pass through the frame structure, and particularly when the powder cleaning station is used, the pedal 2 facilitates the operation staff to stand around the powder cleaning cavity, and safe and reliable protection and support are provided for the operation staff.

The powder cleaning bracket 3 is used for installing a powder cleaning cavity and accessory equipment for cleaning powder, and is an independent module convenient to assemble and disassemble.

The cavity supporting bracket 5 is used for installing a printing cavity, has good structural rigidity, is a core station of the metal 3D printing equipment, and is a place where the equipment prints a workpiece.

The auxiliary bracket 7 is used for installing a laser and a device host, the main installation parts listed above for the auxiliary bracket 7 can be used for installing other components included in the metal 3D printing device in an integrated manner, such as installation of a gas and water cooling pipeline system, an air duct system, an optical fiber disc, an instrument panel, a water cooling pipeline control box and the like, which are not listed.

The cylinder body transfer platform 4 is used for transferring the forming cylinders, so that the forming cylinders can accurately and flexibly move and position at stations such as printing, powder cleaning and workpiece taking, and a good expansion space is provided for production line arrangement.

Maintenance preparation and cleaning of equipment before and after printing are facilitated for operators through the overhaul mobile platform 6, so that maintenance is simple and convenient, safe and reliable.

The embodiment adopts a modularized design, so that each component can be modularized and integrated on a rack structure, the processing, the manufacturing and the assembly are greatly facilitated, the compatibility is good, the universality and the module expansibility are good, the flexible adjustment can be realized according to the change of the size parameters of equipment, and the use is convenient. In addition, the frame structure of the embodiment is easy to manufacture, simple to assemble and convenient to maintain in the later period. The frame structure is successfully applied to large-scale metal 3D printing equipment with the size of more than 800mm of the company, and good use effect and economic benefit are obtained.

The metal 3D printing apparatus includes other components, such as a PLC controller, a powder feeding and feeding system, a dust and smoke filtering system, a powder overflow recycling system, and the like, except for the frame structure, the powder cleaning chamber, the auxiliary apparatus for powder cleaning, the printing chamber, the laser, the apparatus host, and the electric cabinet 9 described in this embodiment, and other non-illustrated corresponding integrated components are mounted on the corresponding parts of the frame structure, which are not described in detail.

Referring to fig. 7, the adjustable foot 8 includes a heavy-duty adjustable foot 80; the heavy-load adjustable anchor 80 comprises a first base 801, a first screw rod 802, a first nut 803 and a nut pad 804, wherein the first base 801 is in spherical hinge connection with the lower end of the first screw rod 802, two first nuts 803 are installed on the first screw rod 802, and the nut pad 804 is also installed above the two first nuts 803 on the first screw rod 802. The first nut 803 positioned below is fixed with the first screw 802 in a one-piece structure, and the nut pad 804 and the first nut 803 positioned above can be moved by threads on the first screw 802; the upper end of the first screw 802 is screwed with the load-bearing chassis 1, and the nut pad 804 is connected with the load-bearing chassis 1 through a fastener, which may be a bolt, a nut, a screw, etc.

Referring to fig. 8, the first stand 801 is provided with a spherical groove 8010, and a ball head 8020 matched with the spherical groove 8010 is provided at the lower end of the first screw 802.

In this embodiment, the heavy-load adjustable anchor 80 is supported on the ground through the first foot stand 801, and the first foot stand 801 and the first nut 803 are hinged in a spherical manner, so as to be applicable to a concave-convex ground, and have low requirements on the foundation ground. The leveling of the bearing underframe 1 is realized through a plurality of heavy-load adjustable feet 80, and the leveling is convenient. The first nut 803 positioned below is fixed with the first screw 802 into an integral structure, so that tools such as a wrench can conveniently adjust the first screw 802 by screwing the first nut 803, and the operation is convenient. The fixed locking is realized through the nut pad 804 and the first nut 803 positioned above, so that the locking is stable and reliable. The first nut 803 and the first screw 802, and the nut pad 804 and the first screw 802 are engaged with each other by a stepped thread, so that the stepped thread has strong bearing property. The single heavy load adjustable foot 80 of this embodiment can bear more than 6 tons.

Referring to fig. 9, the adjustable anchor 8 further includes a common adjustable anchor 81, where the common adjustable anchor 81 includes a second base 810, a second screw 811, and a second nut 812, where the second base 810 is fixedly connected with a lower end of the second screw 811, two second nuts 812 are installed on the second screw 812, the second nut 812 located below is fixed with the second screw 811 into an integral structure, the second nut 812 located above can move with respect to the second screw 811 by threads, and an upper end of the second screw 811 is in threaded connection with the load-bearing chassis 1.

In this embodiment, the plurality of adjustable feet 8 includes a plurality of heavy load adjustable feet 80 and a plurality of common adjustable feet 81, wherein the specific number of the heavy load adjustable feet 80 and the common adjustable feet 81 is selected according to the specific requirements of the device, which is not limited specifically.

In this embodiment, the common adjustable anchor 81 is supported on the ground by the second anchor 810, and has a simple structure and convenient leveling. Wherein the second nut 812 positioned below is fixed with the second screw 811 in an integrated structure, so that tools such as a wrench can conveniently adjust the second screw 811 by screwing the second nut 812, and the operation is convenient. The fixed locking is achieved by a second nut 812 located above.

Referring to fig. 2, the cylinder transferring platform 4 includes a transferring platform body 40 and a first moving driving mechanism 41, where the transferring platform body 40 is movably mounted on the bearing chassis 1 through a guide rail and guide groove structure; the first movement driving mechanism 41 is connected to the transfer platform body 40 and is used for driving the transfer platform body 40 to move axially relative to the bearing underframe 1.

Referring to fig. 2 and 5, the maintenance moving platform 6 includes a maintenance frame 60, a maintenance platform body 61, a second moving driving mechanism 62 and a lifting driving mechanism (not shown in the drawing), the maintenance frame 60 is movably mounted on the bearing chassis 1 through a guide rail guide groove structure, the maintenance platform body 61 is mounted on the maintenance frame 60 through the lifting driving mechanism, the lifting driving mechanism is used for driving the maintenance platform body 61 to lift up and down, and the second moving driving mechanism 62 is connected with the maintenance frame 60 and is used for driving the maintenance frame 60 to axially move relative to the bearing chassis 1. Preferably, the lifting driving mechanism adopts a scissor type lifting platform, and the scissor type lifting platform is a mature product used by the existing engineering equipment such as a crane and the like, so that the specific description is omitted.

In this embodiment, the first movement driving mechanism 41 adopts a structure of a rack and pinion acceleration/deceleration machine and an electric motor, and the structure is the same as the second movement driving mechanism 62, and the second movement driving mechanism 62 is described in detail as follows: referring to fig. 6, the second moving driving mechanism 62 includes a motor 620 fixedly installed on the service rack 60, a speed reducer 621 fixedly installed on the service rack 60 and connected to an output shaft of the motor 620, a driving gear 622 installed on an output shaft of the speed reducer 621, and a rack (not shown) axially disposed along the load-bearing chassis 1, wherein the driving gear 622 is engaged with the rack. When the second movable driving mechanism 62 works, the motor 620 is started to drive the speed reducer 621 to work, the speed reducer 621 drives the driving gear 622 to rotate, and under the action of the rack, the maintenance frame 60, the motor 620, the speed reducer 621 and the driving gear 622 are driven to move relative to the rack, so that the maintenance frame 60 is axially moved relative to the bearing underframe 1. The structure of the first movement driving mechanism 41 is the same as that of the second movement driving mechanism 62, and thus will not be described.

In this embodiment, the transferring platform body 40 is movably mounted on the bearing chassis 1 through a guide rail guiding structure, and the guide function of the transferring platform body 40 during axial movement relative to the bearing chassis 1 is realized through the guide rail guiding structure. In this embodiment, the maintenance frame 60 is movably mounted on the bearing chassis 1 through a guide rail guiding structure, and the guide function of the maintenance frame 60 when axially moving relative to the bearing chassis 1 is realized through the guide rail guiding structure. Wherein guide rails 101 of the guide rail guide groove structure are arranged on the bearing underframe 1, the number of the guide rails 101 is two, the two guide rails 101 are axially arranged at intervals in parallel, guide grooves 600 are formed in the transfer platform body 40 and the overhaul frame 60, and the guide rails 101 are shared by the transfer platform body 40 and the overhaul frame 60.

In this embodiment, the overhauling mobile platform 6 further includes a tool rack 63 disposed on the table top of the overhauling platform body 61, and tools for maintenance, cleaning and the like are placed through the tool rack 63, so as to facilitate daily maintenance and cleaning work.

Referring to fig. 1 and 3, the tread base 2 is of a stationary construction. Referring to fig. 3 and 4, or the pedal table 2 is in a turnover structure, the pedal table 2 comprises a pedal table 201, a turning plate 202 and an electric push rod 203, the pedal table 201 is fixedly installed on the bearing chassis 1, the turning plate 202 is positioned in the middle of the table top of the pedal table 201, and the turning plate 202 is rotatably connected with the pedal table 201; the fixed end of the electric push rod 203 is rotationally connected with the bearing chassis 1, and the telescopic end is rotationally connected with the turning plate 202, so that the related rotational connection can be performed by adopting the existing pin shaft, and other rotational connection modes can be adopted, which is the existing mature technology, so that excessive description is not made.

The foregoing has shown and described the basic principles, principal features and advantages of the utility model. It will be understood by those skilled in the art that the present utility model is not limited to the embodiments described above, and that the above embodiments and descriptions are merely illustrative of the principles of the present utility model, and various changes and modifications may be made without departing from the spirit and scope of the utility model, which is defined in the appended claims. The scope of the utility model is defined by the appended claims and equivalents thereof.

Claims

1. The frame structure of the large-scale metal 3D printing equipment is characterized by comprising a bearing chassis (1), wherein a pedal table (2) used for passing, a powder cleaning support (3) used for cleaning a powder cavity and accessory equipment used for cleaning powder, a cavity supporting support (5) used for installing a printing cavity and an auxiliary support (7) are sequentially arranged above the bearing chassis (1) from one end to the other end, and the auxiliary support (7) is used for installing a laser and an equipment host; a plurality of adjustable feet (8) for supporting and leveling the bearing underframe (1) are arranged below the bearing underframe (1);

the middle of bearing chassis (1) top is installed cylinder body transfer platform (4) and is overhauld moving platform (6) by one end to the other end in proper order, cylinder body transfer platform (4) and overhaul moving platform (6) can be followed bearing chassis (1) axial displacement, step on platform (2), clear powder support (3) and cavity support (5) cover cylinder body transfer platform (4), cavity support (5) and auxiliary stand (7) cover overhaul moving platform (6).

2. The frame structure of a large metal 3D printing apparatus according to claim 1, characterized in that the adjustable feet (8) comprise heavy duty adjustable feet (80); the heavy-load adjustable foundation (80) comprises a first foot seat (801), a first screw rod (802), first nuts (803) and nut pads (804), wherein the first foot seat (801) is in spherical hinge connection with the lower end of the first screw rod (802), two first nuts (803) are installed on the first screw rod (802), and the nut pads (804) are also installed above the two first nuts (803) on the first screw rod (802);

-said first nut (803) located below is fixed in a unitary structure with said first screw (802), said nut pad (804) and said first nut (803) located above being movable by threads on said first screw (802); the upper end of the first screw rod (802) is in threaded connection with the bearing underframe (1), and the nut pad (804) is connected with the bearing underframe (1) through a fastener.

3. The frame structure of a large-scale metal 3D printing apparatus according to claim 2, wherein the adjustable anchor (8) further comprises a common adjustable anchor (81), the common adjustable anchor (81) comprises a second base (810), a second screw rod (811) and a second nut (812), the second base (810) is fixedly connected with the lower end of the second screw rod (811), two second nuts (812) are installed on the second screw rod (811), the second nut (812) located below is fixed with the second screw rod (811) into an integral structure, the second nut (812) located above is capable of moving in a threaded manner relative to the second screw rod (811), and the upper end of the second screw rod (811) is in threaded connection with the bearing chassis (1).

4. The frame structure of a large metal 3D printing apparatus according to claim 2, wherein the first nut (803) and the first screw (802), and the nut pad (804) and the first screw (802) are in a ladder-type threaded fit.

5. The frame structure of the large-scale metal 3D printing apparatus according to claim 2, wherein the first foot stand (801) is provided with a spherical groove (8010), and the lower end of the first screw (802) is provided with a ball head (8020) matched with the spherical groove (8010).

6. The frame structure of a large-scale metal 3D printing apparatus according to claim 1, wherein the cylinder transfer platform (4) comprises a transfer platform body (40) and a first movement driving mechanism (41), and the transfer platform body (40) is movably mounted on the bearing chassis (1) through a guide rail and guide groove structure; the first movement driving mechanism (41) is connected with the transfer platform body (40) and is used for driving the transfer platform body (40) to axially move relative to the bearing underframe (1).

7. The frame structure of a large-scale metal 3D printing apparatus according to claim 1, wherein the maintenance moving platform (6) comprises a maintenance frame (60), a maintenance platform body (61), a second moving driving mechanism (62) and a lifting driving mechanism, the maintenance frame (60) is movably mounted on the bearing chassis (1) through a guide rail guiding groove structure, the maintenance platform body (61) is mounted on the maintenance frame (60) through the lifting driving mechanism, the lifting driving mechanism drives the maintenance platform body (61) to lift up and down, and the second moving driving mechanism (62) is connected with the maintenance frame (60) and is used for driving the maintenance frame (60) to axially move relative to the bearing chassis (1).

8. The frame structure of a large metal 3D printing apparatus according to claim 7, wherein the inspection moving platform (6) further comprises a tool rack (63) provided on a table top of the inspection platform body (61).

9. The frame structure of a large metal 3D printing apparatus according to claim 7, wherein the elevation driving mechanism employs a scissor type elevation platform.

10. The frame structure of a large metal 3D printing apparatus according to claim 1, characterized in that the tread table (2) is of a fixed structure;

or the pedal table (2) is in a turnover structure, the pedal table (2) comprises a pedal table frame (201), a turning plate (202) and an electric push rod (203), the pedal table frame (201) is fixedly arranged on the bearing bottom frame (1), the turning plate (202) is positioned in the middle of the table top of the pedal table frame (201), and the turning plate (202) is rotationally connected with the pedal table frame (201); the fixed end of the electric push rod (203) is rotationally connected with the bearing chassis (1), and the telescopic end is rotationally connected with the turning plate (202).