CN112238610A

CN112238610A - Powder paving equipment, 3D printing device and powder paving method

Info

Publication number: CN112238610A
Application number: CN202011020239.7A
Authority: CN
Inventors: 庞伟; 俞红祥; 董胜男
Original assignee: Hangzhou Dedi Intelligent Technology Co ltd
Current assignee: Hangzhou Dedi Intelligent Technology Co ltd
Priority date: 2020-09-25
Filing date: 2020-09-25
Publication date: 2021-01-19

Abstract

The invention relates to powder paving equipment, a 3D printing device and a powder paving method. Spread powder equipment and include the major structure, spread powder cylinder and roller driving piece, wherein the major structure is used for installing on the motion module, spreads the powder cylinder and rotationally installs on the major structure, and the surface of spreading the powder cylinder is provided with flexible brush structure. The roller driving piece is arranged on the main body structure and is in driving connection with the powder spreading roller. When the powder spreading machine is used, the roller driving piece drives the powder spreading roller to rotate, the powder layer spread on the powder spreading area is swept flat through the flexible sweeping structure, the powder spreading shearing force can be reduced to be small, the interference to a workpiece needing to be processed is small, and the powder spreading is smooth.

Description

Powder paving equipment, 3D printing device and powder paving method

Technical Field

The invention relates to the field of processing equipment, in particular to powder paving equipment, a 3D printing device and a powder paving method.

Background

The 3D printing technology adopts a layer-by-layer accumulation mode to form a three-dimensional object, the used material type and material form range are wide, and the problem of cutter interference of numerical control cutting machining can be effectively avoided, so that the three-dimensional object can play an advantage in the machining fields of complex contours, cavities, lattices and the like, and is increasingly applied to the fields of consumption, industry, aerospace and the like. The powder bed three-dimensional forming is one of the important classifications of 3D printing equipment, which adopts a powder laying mechanism to lay a powder thin layer with uniform thickness on the edge opening of a forming cylinder, adopts a thermal scanning device to selectively heat a specific area of the powder thin layer, leads the powder in the heated area to generate melting or sintering phenomenon, and cools to obtain a sheet-shaped combination. And then through the repeated execution of the steps of descending layer by layer, powder laying and thermal scanning of the forming platform, the flaky cured material obtained by thermal scanning of each layer is vertically welded, so that the three-dimensional formed object is obtained, and the three-dimensional formed object has the characteristics of high forming precision, high part surface quality, low support structure tolerance, simple part post-treatment and the like. Because of the fine granularity of the powder material and the accurate control capability of the selective laser beam heating, compared with other types of 3D printing equipment, the SLM and SLS equipment have the outstanding characteristic of high forming accuracy, and because the powder material has good dynamic fluidity and static support performance at the same time, the SLM and SLS equipment also have the additional advantages of low support structure dependence and simple post-processing when building three-dimensional parts.

In 3D printing apparatus, handle in the data model processing and wait to print the model itself outside, still need add the support, the effect of support has different effects in different technology types, and in the FDM technology, the effect of support is for propping follow-up printing entity, prevents because the action of gravity drops or hangs from above. The support in the SLM process is used for fixing the printed model and conducting heat, the printed model needs to be fixed, powder bed equipment has powder spreading action, and when the powder scraper moves on the printed model in the powder spreading process, shearing force exists, if the printed model is not supported and fixed, the printed model can be displaced under the action of the shearing force, so that the printing dislocation and deformation of the model can be caused. The SLS process has the same shearing force in the powder spreading process, but because the powder around the solidified model can be softened to a certain degree due to the heating effect, the effect of fixing the printing model is achieved, and therefore the SLS process does not need to add support. Whether the printing model is provided with the support or not has the influence, after the support is added to print, the support is difficult to remove and influences the surface quality of the model, the space occupied by the support reduces the placing quantity of parts, the placing angle of the parts is limited, and particularly in an SLM (selective laser melting) process, the support is difficult to remove and limits the printing of a porous structure and a complex structure.

Disclosure of Invention

In view of the above, the invention provides a3 powder paving device, a 3D printing apparatus and a powder paving method, so as to solve the technical problem that the printing quality of a workpiece is easily reduced due to a large shearing force during powder paving in the powder paving device in the prior art.

The invention provides a powder paving device, which comprises: the main body structure is used for being installed on the motion module; the powder spreading roller is rotatably arranged on the main body structure, and the surface of the powder spreading roller is provided with a flexible sweeping structure; the roller driving piece is arranged on the main body structure, is in driving connection with the powder paving roller and is used for driving the powder paving roller to rotate.

So set up, can effectively promote and spread the powder effect, reduce the shearing force.

Optionally, spread powder equipment still includes the sharp module, and the motion module is the sharp module, and the sharp module drives the major structure and makes conveyer belt subassembly accomplish the plane and spread the powder along linear motion.

So set up, can make motion module simple structure, the motion is reliable.

Optionally, the powder laying apparatus further comprises: the powder storage box is arranged on the main body structure, the lower part of the powder storage box is provided with a powder outlet, and powder in the powder storage box can flow out from the powder outlet under the action of gravity; the conveyer belt subassembly is installed in the below of storing up the powder box, and the powder that the powder mouth flows is accepted to the conveyer belt subassembly, and the conveyer belt subassembly is under the moving state, and the powder that the powder mouth flows is spread on the conveyer belt subassembly, and the conveyer belt subassembly will flow out the powder and transport to treating the powder region of spreading.

So set up, the conveyer belt subassembly is under the operating state, and the powder that goes out the powder mouth outflow can be comparatively even spread on the conveyer belt subassembly, and the motion module drives the major structure and treats the regional motion of spreading the powder, and the conveyer belt subassembly just can transport the powder that flows to treat to spread the powder region, and the powder more even shop that realizes storing up in the powder box is treating to spread the powder region. Therefore, the stress on the workpiece generated during the powder trowelling and spreading can be reduced, and the relatively fixed state can be kept even without a supporting process.

Optionally, the powder laying apparatus further comprises: the powder outlet control piece is movably arranged and used for controlling the size of an opening of the powder outlet.

So set up, can realize controlling out the powder volume as required.

Optionally, the powder outlet is arranged on the side surface of the lower part of the powder storage box, and the powder outlet control piece is movably arranged on the main body structure along the vertical direction.

So set up, can make the position of meal outlet control piece adjust, and adjust in a flexible way.

Optionally, the powder outlet is provided in two, and is arranged on two opposite sides of the powder storage box along the conveying direction of the conveyor belt assembly.

So set up, can satisfy the play powder demand better.

Optionally, the bottom of the powder reservoir is in communication with the headspace of the conveyor assembly.

So set up, can guarantee to go out powder and carry reliably.

Optionally, the conveyor belt assembly comprises: two rollers mounted on the main structure at intervals; a conveyor belt mounted on the two rollers; and the conveyor belt driving part is arranged on the main structure and is in driving connection with at least one of the two rollers.

With the arrangement, a better conveying effect can be ensured.

According to another aspect of the invention, a 3D printing device is provided, which includes a powder spreading apparatus, and the powder spreading apparatus is the above powder spreading apparatus.

So set up for 3D printing device's the success rate of printing is better, can effective reduce cost.

According to another aspect of the present invention, there is provided a dusting method comprising: driving a powder outlet of a powder storage box in powder paving equipment of the 3D printing device to be opened, and enabling powder to flow out of the powder outlet onto a conveyor belt component of the powder paving equipment; driving the conveyor assembly to move to transport the outflowing powder to the area to be dusted

So set up for can make shop's powder process stable, reliable, and the shearing force is little.

Drawings

Fig. 1 shows a first schematic oblique-side construction of an embodiment of a dusting apparatus according to the invention;

FIG. 2 shows a second schematic oblique-side construction of the embodiment of the dusting apparatus of FIG. 1;

FIG. 3 shows a schematic partial structure of the powder laying apparatus of FIG. 1;

FIG. 4 is a schematic view of the powder laying apparatus of FIG. 1 in operation and a partially enlarged view thereof;

fig. 5 shows a schematic structural diagram of burrs on the surface of a workpiece encountered during operation of the powder laying device of fig. 1 and a partially enlarged schematic diagram thereof.

Description of reference numerals:

10. a body structure; 20. storing the powder box; 21. a powder outlet; 30. a conveyor belt assembly; 31. a roller; 32. a conveyor belt; 33. a conveyor drive; 40. a linear module; 50. a powder outlet control member; 51. a lifting moving module; 60. a powder spreading roller; 61. a flexible wiper structure; 70. a roller drive.

Detailed Description

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is apparent that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.

It will be understood that when an element is referred to as being "mounted on" another element, it can be directly mounted on the other element or intervening elements may also be present. When a component is referred to as being "disposed on" another component, it can be directly on the other component or intervening components may also be present. When an element is referred to as being "secured to" another element, it can be directly secured to the other element or intervening elements may also be present.

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

In order to enable a workpiece in 3D printing equipment to be kept in a relatively fixed state even if no supporting process is available, the technical scheme provided by the invention is to provide a technical scheme capable of reducing the powder spreading shearing force, so that the interference on the workpiece needing to be processed is reduced, and the powder spreading smoothness and good adaptability to model warping can be ensured. The technical scheme is particularly suitable for powder paving processes of powder bed equipment such as SLM and SLS.

Specifically, as shown in fig. 1, fig. 2, fig. 3 and fig. 4, the powder spreading device of the present invention comprises a main body structure 10, a powder spreading roller 60 and a roller driving member 70, wherein the main body structure 10 is used for being mounted on a moving module, the powder spreading roller 60 is rotatably mounted on the main body structure 10, and the surface of the powder spreading roller 60 is provided with a flexible sweeping structure 61. The roller driving member 70 is mounted on the main body structure 10 and is in driving connection with the powder laying roller 60. When the powder spreading machine is used, the roller driving piece 70 drives the powder spreading roller 60 to rotate, the powder layer spread on the powder spreading area is swept flat through the flexible sweeping structure 61, the powder spreading shearing force can be reduced, the interference to a workpiece to be processed is small, and the powder spreading is smooth.

Optionally, in the technical solution of the present embodiment, the flexible sweeping brush structure 61 is an elastic soft hair, and as another optional embodiment, the flexible sweeping brush structure 61 may also be a fine rubber column. In the technical scheme of the embodiment, the elastic soft hair is distributed on the powder paving roller 60 according to a certain rule, the elastic soft hair is high-temperature resistant and has certain toughness, the elastic soft hair is distributed on the same high line of the powder paving roller 60 according to a certain interval, the elastic soft hair on the adjacent high line is not adjacent, the powder paving roller 60 moves horizontally during powder paving, the powder paving roller 60 rotates simultaneously, and all the elastic soft hair is equivalently paved side by side during the powder paving process according to the ratio of the horizontal movement speed to the edge rotation linear speed of the roller. If the height of the powder spreading roller 60 is h, the radius is r, and the diameter of the elastic soft bristles is d, the number of the elastic soft bristles which can be arranged on a circle with any height is n 1-2 r pi/d, the number is rounded, the arrangement distance of the elastic soft bristles on a high line of the powder spreading roller 60 is x, the number of the elastic soft bristles which can be arranged on the high line is n 2-h/x, the number of the elastic soft bristles which can be arranged on the whole powder spreading roller 60 is n 1-n 2 under the condition that the elastic soft bristles on the high line are arranged at equal intervals and the elastic soft bristles on the adjacent high line are not adjacent, and the number of the elastic soft bristles is uniformly distributed on the surface of the powder spreading roller 60. The number of the elastic soft wool densely paved at a single high line is h/d, and when the ratio of the linear speed of the powder paving roller 60 to the horizontal moving speed of the powder paving roller is n1 n2/h/d in the powder paving process, the method is equivalent to the traditional linear powder paving process.

It should be noted that, in the conventional 3D printing apparatus, the warping of the printed workpiece may damage the powder spreading and leveling device, which may result in uneven powder spreading and failed printing on the entire workpiece. In the technical scheme of the invention, the flexible sweeping and brushing structure 61 arranged on the surface of the powder spreading roller 60 can sweep the warping part of the workpiece without being damaged or exerting excessive shearing force on the workpiece. This powder technical scheme is spread to low shearing force, when the powder process is small to printing work piece interference, corresponding, the warpage condition that has printed the work piece probably produced is also little to the interference of spreading the powder ware, when the warpage appears in printing the work piece, traditional line powder spreading method does not dodge the mechanism and exists, leads to warping work piece will spread the powder adhesive tape and scrape brokenly, and then can not be with the powder smooth laying on the powder bed again, leads to printing the failure.

According to the powder spreading method, when the printed workpiece is warped, the elastic soft hair has a certain height, and is elastic and tough at the same time, so that the elastic soft hair can avoid the warped position in the powder spreading moving process, and the elastic soft hair is uniformly distributed on the powder spreading roller 60 and has a certain distance, so that the warped position and the non-warped position have a natural selection function in the powder spreading principle, the stability of powder spreading by the method is further enhanced, and the application range of the method is expanded.

Specifically, spread powder cylinder 60 in the work of floating, as figure 3, evenly distributed elasticity fluff on spreading powder cylinder 60, when spreading powder cylinder 60 and rotating, elasticity fluff and powder contact to promote the powder to spread powder direction, spread powder direction both sides and remove, because elasticity fluff evenly distributed, the motion of powder toward spreading powder direction both sides can be offset, and the displacement along spreading powder direction then can add up. Printed workpiece b is present in powder a 1; when the powder is laid on the printed workpiece b, only the elastic fluff is contacted with the powder at the same time, and the shearing force does not have any influence on the printed workpiece; with the rotation of the powder spreading roller 60 and the movement of the powder spreading device, the powder spreading roller 60 spreads the pre-spread transferred powder a2 falling on the powder spreading surface to form a flat powder surface a 3. As shown in fig. 5, when a warped part b1 of the printed workpiece b is encountered, the warped part is higher than the powder spreading surface, the powder a2 transferred by pre-spread powder exists on the powder spreading surface, when the powder spreading roller 60 moves to a warped part b1, the elastic soft hair bends when contacting the warped part b1, the elastic soft hair passes over the warped part b1 along with the rotation of the powder spreading roller 60 and returns to the original shape, and other elastic soft hairs contacting the same undergo the same process; when the powder-spreading roller 60 passes over the warped portion b1, a flat powder-spreading surface a3 is formed on the powder-spreading plane except for the warped portion b 1.

As shown in fig. 1 and fig. 2, in the technical solution of this embodiment, the powder spreading apparatus further includes a powder storage box 20 and a conveyor belt assembly 30, the powder storage box 20 is installed on the main structure 10, a powder outlet 21 is opened at a lower portion of the powder storage box 20, and the powder in the powder storage box 20 can flow out from the powder outlet 21 under the action of gravity. Conveyer belt assembly 30 is installed in the below of powder storage box 20, and conveyer belt assembly 30 accepts the powder that powder outlet 21 flows out, and conveyer belt assembly 30 is under the operating condition, and the powder that powder outlet 21 flows out is spread on conveyer belt assembly 30, and conveyer belt assembly 30 transports the powder that flows out to waiting to spread the powder region.

By applying the technical scheme of the invention, when the conveyor belt assembly 30 is in a running state, the powder flowing out of the powder outlet 21 can be uniformly spread on the conveyor belt assembly 30, the movement module drives the main body structure 10 to move on the area to be spread, and the conveyor belt assembly 30 can transport the flowing-out powder to the area to be spread, so that the powder in the powder storage box 20 can be uniformly spread on the area to be spread. Therefore, the stress on the workpiece generated during the powder trowelling and spreading can be reduced, and the relatively fixed state can be kept even without a supporting process.

As an optional implementation manner, in the technical solution of this implementation manner, as shown in fig. 1 and fig. 2, the powder spreading apparatus further includes a linear module 40, the moving module is the linear module 40, and the linear module 40 drives the main body structure 10 to move along a straight line so that the conveyor belt assembly 30 completes plane powder spreading and also enables the powder spreading roller 60 to complete leveling. Wherein the linear module 40 is arranged along the powder spreading direction. In the technical solution of the present embodiment, the linear module 40 is a part of the powder laying apparatus. As another alternative, the powder laying apparatus may not include the linear module 40, and the main body structure 10 may be mounted on a motion module associated with the 3d printing apparatus during use.

Preferably, in the technical solution of the present embodiment, as shown in fig. 2 and 3, the powder spreading apparatus further includes: the powder outlet control element 50 is movably arranged, and the powder outlet control element 50 is used for controlling the opening size of the powder outlet 21. The powder outlet control member 50 controls the size of the opening of the powder outlet 21 and can control the powder thickness on the conveyor belt assembly 30, thereby realizing control of the powder spreading thickness of the powder spreading area to be spread in one aspect so as to adapt to different printing layer thicknesses. On the other hand, the control of the powder spreading thickness of the powder spreading area can also be realized by controlling the moving speed of the moving die set or the linear die set 40.

As an alternative embodiment, the powder outlet 21 is opened at a side of a lower portion of the powder storage box 20, and the powder outlet control member 50 is movably installed on the main body structure 10 in a vertical direction. More preferably, a lifting moving module is provided on the main body structure 10, and the powder outlet controller 50 is installed on the lifting moving module. Optionally, the powder outlet control member 50 is annular and is sleeved on the powder storage box 20.

As another alternative, the powder outlet 21 may be formed on the bottom of the lower portion of the powder storage box 20. In this embodiment, the top of the conveyor belt assembly 30 is spaced from the powder outlet 21.

As shown in fig. 3, in the present embodiment, the powder outlet 21 is provided in two and is opened on two opposite sides of the powder storage box 20 along the transport direction of the conveyor belt assembly 30. In this embodiment, the conveyor belt assembly 30 moves according to the arrow in fig. 3, and powder is spread on the conveyor belt assembly 30 mainly through the powder outlet 21 on the right side. In addition, the conveyor belt assembly 30 can also move in the direction opposite to the arrow direction in fig. 3, so that the powder can be spread on the conveyor belt assembly 30 through the powder outlet 21 on the left side, and the two-way powder spreading requirement is realized. Correspondingly, the annular powder outlet control member 50 is sleeved on the powder storage box 20, and can simultaneously control the opening sizes of the two powder outlets 21.

In the solution of the present embodiment, the bottom of the powder storage box 20 is in communication with the headspace of the conveyor belt assembly 30. As shown in fig. 1, the bottom of the powder container 20 is completely clear of the top space of the conveyor assembly 30, which avoids difficulties in discharging powder due to the resistance to flow of the powder in the powder container 20. It should be noted that, the fact that the bottom of the powder storage box 20 is communicated with the top space of the conveyor belt assembly 30 means that the bottom of the powder storage box 20 is attached to the top of the conveyor belt assembly 30, but the bottom of the powder storage box 20 is a structure which is completely or partially hollow.

As an alternative embodiment, a portion of the conveyor assembly 30 may be mounted within the powder container 20 between the two powder outlets 21, and the conveyor assembly 30 may carry powder out of the powder container 20. In this embodiment, the powder container 20 is provided with a bottom, and in use, a portion of the belt 32 of the belt assembly 30 is inserted into the powder container 20, and the belt 32 rotates to directly carry powder out of the powder container 20.

In the solution of the present embodiment, the conveyor belt assembly 30 includes two rollers 31, a conveyor belt 32 and a conveyor belt driving member 33, the two rollers 31 are mounted on the main structure 10 at intervals, the conveyor belt 32 is mounted on the two rollers 31, and the conveyor belt driving member 33 is mounted on the main structure 10 and is in driving connection with one of the two rollers 31. As shown in fig. 2, the right roller 31 is a driving roller, the left roller 31 is a driven roller, and the belt driving member 33 is drivingly connected to the driving roller. Optionally, the belt drive 33 is a motor or a rotary cylinder.

As another alternative, two belt drives 33 may be provided, and two belt drives 33 are drivingly connected to the two rollers 31.

If the powder thickness h1 actually laid is equal to the linear speed v2 of the conveyor belt 32 and the linear speed v1 of the moving module or the linear module 40, the powder laying thickness on the conveyor belt 32 is h2> -h 1, a proportionality coefficient p is taken so that h 2-h 1 p, wherein p > -1, namely the powder laying amount on the conveyor belt 32 is not less than the final powder laying amount, and when v1 is not equal to v2, the powder volume actually required in unit time t is v1 t h1, the powder laying volume on the conveyor belt 32 is v2 t h1 p, and p > -v 1/v 2; when p is equal to 1, the volume of the pre-laid powder is completely equal to the volume of the actually laid powder in an ideal state, the powder falls synchronously in the powder laying process, the powder scraper performs a smoothing action on the powder falling to the powder laying surface at the moment, and the powder cannot be accumulated in the moving process, so that the powder laying process can be performed quickly, but considering that a printed area in the actual printing process may sink to a certain extent, the sinking position needs more powder to be laid smoothly, therefore, p is larger than 1, and the specific number can be adjusted according to the actual printing effect.

The compaction effect of the powder spreading layer is realized by vertical downward kinetic energy carried by powder falling onto a powder spreading plane through a free falling body, the module of the conveyor belt 32 has a certain height from the powder spreading platform, the impact and compaction effects exist due to the contact speed when the powder falls onto the powder spreading surface after passing through the free falling body with the height, the mass of the powder particles is set as m, the speed when the powder particles contact the powder spreading surface is v, the time required by the speed after the powder particles contact the powder spreading surface is reduced to 0 is t, the impact force f is m v/t, when the powder falls and impacts the powder spreading surface, the powder is not carried out one by one, but a large amount of powder is carried out simultaneously in a short time, so the mass of the calculated powder is calculated according to the total mass of the falling powder in a certain time, and the impact force is the resultant force of all the powder particles in the time period.

In the technical scheme of the low-shearing-force powder spreading, the powder is pre-spread by the conveyor belt 32 and then transferred, so that the thickness and distribution of the powder falling on a powder spreading plane are very close to the actual spreading thickness, and powder accumulation does not exist in the spreading process, therefore, the powder spreading roller 60 mainly completes the function of leveling the powder, and in order to achieve the purpose of enabling the powder spreading process to be free of interference on a printed workpiece, the contact area of the powder spreading roller 60 and the powder surface at the same time needs to be reduced, and further the contact area of the powder spreading roller 60 and the printed workpiece at the same time is reduced, so that the purpose that the powder can be pushed at each moment in the powder spreading process but the printed workpiece cannot be pushed is achieved, and the purpose that the powder can be prepared to be pushed in the whole powder spreading process, but the printed workpiece cannot move all the time is.

In the powder spreading process, the actual effective part of the powder spreading action is in the linear region of the contact position of the powder spreading roller 60, so that the pre-spreading powder area on the conveyor belt assembly 30 is not required to be the same as the actual spreading area, and only a small-area rectangular powder spreading surface needs to be constructed and can be continuously supplied.

In the technical solution of the present embodiment, the powder spreading roller 60 is located below the conveyor belt assembly 30, that is, after the conveyor belt assembly 30 conveys the powder to the area to be spread, the powder spreading roller 60 sweeps the spread powder.

The technical scheme of the low-shearing-force powder paving process provided by the invention decomposes the traditional line powder paving process, so that only single points push the powder at the same time, and the pushing points have certain intervals, thereby achieving the purpose of asynchronously paving a large amount of single points on the powder without pushing the printed workpiece. The technical scheme of the low-shear-force powder spreading has small interference on the force of the printed unsupported workpiece, and has good avoidance and good adaptation effects on the warped workpiece in the printing process; according to the technical scheme of the low-shear-force powder spreading, the horizontal thrust of the powder spreading process on the printed workpiece is extremely small, the printed workpiece cannot be moved sufficiently, and meanwhile, the powder spreading process has good adaptability to the warping condition of the printed workpiece, so that the unsupported printing of the workpiece can be realized in 3D printing equipment of an SLM (selective laser melting) process; the low-shear-force powder paving technical scheme is reasonable, small in interference on printed workpieces, good in adaptability to powder paving scenes of warped workpieces, simple in structure, easy to implement and easy to popularize and apply in various powder paving equipment scenes.

The invention also provides a 3D printing device, and the 3D printing device comprises the powder paving equipment. By adopting the powder paving equipment, the printing precision and reliability of the 3D printing device can be improved.

Optionally, each part of the powder paving equipment can be controlled to work by an independent control system, each part of the powder paving equipment can also be connected into the 3D printing device, and each part of the powder paving equipment is controlled to work by the control system of the 3D printing device.

According to another aspect of the present invention, there is provided a powder laying method of a 3D printing apparatus, the method including: driving a powder outlet of a powder storage box in powder paving equipment of the 3D printing device to be opened, and enabling powder to flow out of the powder outlet onto a conveyor belt component of the powder paving equipment; the conveyor belt assembly is driven to move to transport the outflowing powder to the area to be dusted.

Through this kind of mode conveyer belt assembly 30 will go out the powder that powder mouth 21 flowed out and evenly lay in waiting to spread the powder region for can realize the multiple spot and evenly spread the powder, and control the shop's powder volume of a certain position as required, make and spread the powder effect better.

From the above description, it can be seen that the low-shear-force powder laying technical scheme of the invention realizes time-sharing asynchronous laying of each point and multipoint uniform distribution to realize equivalent integral uniform laying. The powder is transferred after being pre-laid, so that the powder can be accurately and quantitatively supplied to each position of the printing platform, the powder is not accumulated in the powder laying process, the elasticity required by the elastic fluff in the invention is reduced, and the elastic setting can further distinguish the powder from the printed workpiece. The shearing force to the laid powder and the printed workpiece is extremely small, the printed workpiece cannot be displaced in the powder laying process, and the powder bed type 3D printing device, particularly the SLM (selective laser melting) process can be used for completely unsupported printing. In addition, the low-shear-force powder spreading technical scheme has better adaptability to powder spreading scenes with warped printed workpieces or uneven powder surfaces.

Therefore, the technical scheme of the low-shear-force powder paving is reasonable in scheme, simple in structure and easy to implement, unsupported printing is easy to implement, the powder paving scene with warped workpieces has good adaptability, the performance of 3D printing equipment is further improved, the stability of the equipment and the success rate of printing the workpieces are improved, and the use cost of the equipment is reduced.

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

It should be understood by those skilled in the art that the above embodiments are only for illustrating the present invention and are not to be used as a limitation of the present invention, and that suitable changes and modifications of the above embodiments are within the scope of the claimed invention as long as they are within the spirit and scope of the present invention.

Claims

1. A powder paving apparatus, comprising:

a body structure (10), said body structure (10) being for mounting on a motion module;

the powder spreading roller (60) is rotatably arranged on the main body structure (10), and a flexible sweeping structure (61) is arranged on the surface of the powder spreading roller (60);

the roller driving part (70) is installed on the main body structure (10), is in driving connection with the powder paving roller (60) and is used for driving the powder paving roller (60) to rotate.

2. A powder laying apparatus as claimed in claim 1, further comprising:

the powder storage box (20) is mounted on the main body structure (10), a powder outlet (21) is formed in the lower portion of the powder storage box (20), and powder in the powder storage box (20) can flow out of the powder outlet (21) under the action of gravity;

the powder storage box comprises a conveyor belt assembly (30) installed below the powder storage box (20), the conveyor belt assembly (30) receives powder flowing out of the powder outlet (21), the conveyor belt assembly (30) is in a running state, the powder flowing out of the powder outlet (21) is paved on the conveyor belt assembly (30), and the conveyor belt assembly (30) transports the flowing powder to a powder paving area.

3. Powder spreading apparatus according to claim 2, further comprising a linear module (40), wherein the motion module is the linear module (40), and wherein the linear module (40) moves the main structure (10) along a straight line so that the conveyor belt assembly (30) completes a planar powder spreading.

4. A powder laying apparatus as claimed in claim 3, further comprising: the powder outlet control piece (50) is movably arranged, and the powder outlet control piece (50) is used for controlling the size of an opening of the powder outlet (21).

5. Powder spreading equipment according to claim 4, wherein the powder outlet (21) is opened at a side of a lower portion of the powder storage box (20), and the powder outlet control member (50) is movably mounted on the main body structure (10) in a vertical direction.

6. Powder spreading equipment according to claim 3, wherein the powder outlet (21) is two, opening on two opposite sides of the powder storage box (20) in the transport direction of the conveyor belt assembly (30).

7. Powder spreading equipment according to claim 5, wherein the bottom of the powder storage box (20) is in communication with the headspace of the conveyor belt assembly (30).

8. A dusting apparatus according to claim 3, characterized in that said conveyor belt assembly (30) comprises:

two rollers (31) mounted on the main structure (10) at intervals;

a conveyor belt (32) mounted on the two rollers (31);

a belt drive (33) mounted on said body structure (10) in driving connection with at least one of said two rollers (31).

9. A 3D printing apparatus comprising a powder laying device, characterized in that the powder laying device is the powder laying device of any one of claims 1 to 8.

10. A powder laying method of a 3D printing device is characterized by comprising the following steps:

driving a powder outlet (21) of a powder storage box (20) in a powder paving device of the 3D printing device to be opened, and enabling powder to flow out of the powder outlet (21) onto a conveyor belt assembly (30) of the powder paving device;

driving the conveyor belt assembly (30) to move to transport the outflowing powder to an area to be dusted.