EP3538297A1

EP3538297A1 - Powder-based additive manufacturing unit comprising a brush cleaning device

Info

Publication number: EP3538297A1
Application number: EP17800917.1A
Authority: EP
Inventors: Christian GEAY; Miguel Torres-Castellano; Olivier Lauwers; Jeremy CHAGNARD; Alexis TREILHES
Original assignee: Compagnie Generale des Etablissements Michelin SCA
Current assignee: Compagnie Generale des Etablissements Michelin SCA
Priority date: 2016-11-14
Filing date: 2017-11-09
Publication date: 2019-09-18
Also published as: WO2018087475A1; CN110072655B; KR102431669B1; FR3058658A1; CN110072655A; JP2019535903A; KR20190085957A; US20200055247A1; JP7066708B2

Abstract

The invention relates to a powder-based additive manufacturing unit (10) comprising a device (14) for layering the powder, which can be moved along a path connecting a start zone (A) and an end zone (B). The layering device (14) comprises powder-smoothing means (35) for depositing the powder in a powder deposition zone (P) located between the start zone (A) and the end zone (B). The unit (10) also comprises a cleaning device (60) located on the path of the layering device (14), said cleaning device (60) comprising a brush device (62) for brushing at least one surface of the powder-smoothing means (35).

Description

Powder-based additive manufacturing facility with brushing cleaning device

The invention relates to the field of additive manufacturing of a powder-based part.

It relates more particularly to an additive manufacturing facility of a powder-based part and a layering device of such an installation.

An additive manufacturing facility for a powder-based part generally comprises a powder layering device movable along a path connecting a starting zone and an arrival zone, provided with means for depositing the powder. suitable for depositing powder on a powder deposition zone situated between the departure zone and the arrival zone. These powder deposition means comprise for example a hopper, a removable trapdoor compartment, or a metering cylinder provided with a cavity accommodating a dose of powder.

After being deposited on the deposition zone, the powder is most often formed into a layer by means of smoothing means that may be part of the layering device, which preferably comprise a smoothing roller. Then, the powder is sintered or fused by an ad hoc device. These operations are repeated as many times as is necessary to constitute the part.

It can be seen that since the powder used in powder-based additive manufacturing facilities is both volatile and sticky, the latter tends to accumulate and then agglomerate at various points in the setting device. layered during powder deposition cycles. In particular, it has been observed that powder accumulates and forms agglomerates on some surfaces of the smoothing means of the powder, such as the surface of a smoothing cylinder.

However, it happens that the passage of the layering device in the deposition area of the powder, the agglomerates thus formed fall into the deposition zone of the powder. This has the effect of modifying the thickness of the layer of powder to be fused with respect to the desired thickness and thus to reduce the quality of the part that one seeks to manufacture.

Depending on the particle size of the powder and the thickness required for each layer deposited, the error introduced by the presence of these agglomerates is more or less tolerable. Thus, when the order of magnitude of the thickness of the layer is of the order of ten micrometers, the error introduced becomes so important that it may be necessary to interrupt the manufacture of the part and to discard it.

Document FR 2 984 191 discloses an additive manufacturing device for powder base. However, this document does not describe any means for preventing agglomerates of powder from being found in the powder deposition zone.

The object of the invention is therefore to limit the formation of powder agglomerates in the layering device of a powder-based additive manufacturing facility, or at least to limit the risks that they may be found in the powder deposit zone.

For this purpose, the invention relates to a powder-based additive manufacturing facility, comprising a device for layering the powder movable along a path connecting a starting zone and an arrival zone,

the layering device comprising means for smoothing the powder in a powder deposition zone located between the departure zone and the arrival zone,

characterized in that it further comprises a cleaning device located on the path of the layering device, the cleaning device comprising a brushing device for brushing at least one surface of the powder smoothing means.

Due to the presence of the cleaning device on the path of the deposition device, a significant portion of the powder can be removed from the areas of the layering device where it tends to accumulate during powder deposition cycles. Indeed, the brushing device makes it possible to brush the surfaces of the smoothing means of the powder and to dislodge the agglomerates, giving the possibility of evacuating them before they reach the deposition zone of the powder.

This significantly reduces the formation of powder agglomerates and thus limits the risk that they are found in the powder deposit zone.

Advantageously, in order to evacuate the agglomerates before they reach the deposition zone of the powder, the cleaning device comprises a powder suction device for evacuating the powder sucked by this suction device towards a zone of the installation, called the dust collection zone, which is isolated from the powder deposit zone.

According to a preferred embodiment of the invention, the brushing device comprises at least one brush provided with bristles that can bend over the passage of the layering device.

Preferably, the brush is placed at the edge of a suction port of the suction device.

In order to obtain a more efficient cleaning, the bristles of the brush extend in a direction perpendicular to the surface of the smoothing means of the powder with which they come into contact.

Always in order to obtain a more effective cleaning, the brush extending in a substantially longitudinal direction, the layering device moves locally on the path in a direction substantially transverse to the longitudinal direction of the brush.

According to a particular embodiment of the invention, the installation comprises two parallel brushes extending in a longitudinal direction, the layering device moving locally in a direction substantially perpendicular to the longitudinal direction of the brushes.

According to a particular embodiment of the invention, the cleaning device is downstream of the powder deposition zone, considering the path in the direction from the departure zone to the arrival zone.

According to a particular embodiment of the invention, the smoothing means of the powder comprising a smoothing roller, the brushing device brushes the outer surface of the smoothing roller.

According to a particular embodiment of the invention, the layering device further comprising means for depositing the powder, the brushing device brushes at least one surface of the powder deposition means.

Advantageously, the powder deposition means comprising a rotary dosing cylinder, the brushing device brushes the outer surface of the rotary dosing cylinder.

The invention also relates to a powder-based additive manufacturing process by means of a powder-based additive manufacturing facility, comprising a step of cleaning an element of the manufacturing plant, characterized in that

the manufacturing plant is according to the invention and that, during the cleaning step, the washing device is provided with a cleaning path on which the cleaning device is located, the cleaning path being alternative.

Indeed, in order to achieve effective cleaning, it is preferable that the cleaning device cleans several times, for example during an alternating path, the layering device.

To improve the cleaning of the smoothing roller, during the cleaning step, the smoothing roller is rotated.

The invention will be better understood on reading the following description of the appended figures, which are provided by way of examples and are in no way limiting, in which:

- Figure 1 is a perspective view with a section of a powder-based additive manufacturing facility according to a first embodiment of the invention; FIG. 2 is a view of detail II of FIG. 1;

FIG. 3 is a view similar to FIG. 1, in which the layering device is located in a first cleaning zone;

FIG. 4 is a perspective view of detail IV of FIG. 3;

FIG. 5 is a histogram showing the cleaning cycle of the cleaning device of the installation of FIG. 1;

- Figure 6 is a view similar to Figure 1, the layering device being located in a second cleaning zone;

FIG. 7 is a view of detail VII of FIG. 6;

FIG. 8 is a perspective view with a section of a powder-based additive manufacturing facility according to a second, unclaimed embodiment;

FIG. 9 is a view of detail IX of FIG.

FIG. 1 shows a powder-based additive manufacturing facility 10 according to a first embodiment of the invention.

The installation 10 comprises a substantially flat plate 12, above which a layering device 14 is movable along a path connecting a starting zone A of the plate 12 and an arrival zone B of the plate 12 ( for the sake of clarity, the means for moving and guiding the layering device have not been shown in the figures). More particularly, in the embodiments illustrated in the figures, the layering device 14 moves by translating along an axis X.

During its course connecting a departure zone A and an arrival zone B, the layering device passes over a powder deposition zone P of the plateau 12 (also called working zone), located between the arrival zone B and the departure zone A and intended to receive a dose of powder delivered by the layering device 14. This dose of powder is then intended to be fused or sintered by ad hoc means, by example an energy beam such as a laser beam, which have not been shown in the figures.

The deposit area P, of substantially rectangular shape, has four sides

(Only three sides are shown in Figure 1 given the section) surrounded by a recovery tank 16, also called ashtray. The recovery tank 16 can recover any excess powder unused for additive manufacturing, which is pushed by a device provided for this purpose as a squeegee or a roller, for example a smoothing roller as will be seen later.

The layering device 14 comprises, for depositing a dose of powder on the powder deposition zone, powder deposition means 18.

In the first embodiment of the invention illustrated in FIGS. 1 to 7, the powder deposition means 18 comprise storage means comprising a hopper 20, as well as powder dosing means, comprising a rotary measuring cylinder 22 provided with a powder dosing cavity 24.

Powder stored in the hopper 20 can thus be transferred to the dosing cavity 24 by gravity through an opening 26 of the hopper. Then, once the layering device 14 has moved over the deposition zone P, and after a rotation of the metering roll 22, the dose of powder contained in the metering cavity 24 is deposited by gravity on the P. deposit

In this first embodiment of the invention, the metering roll 22 further comprises a flat 28 which makes it possible, during the rotation of the metering roll 22, to prevent the dose of powder thus delivered from being compacted by the metering roll 22. .

The powder deposition means 18 are located in a volume delimited by a casing 30. For this purpose, the casing 30 comprises first lateral walls 32 separating the hopper 20 from the remainder of the layering device 14 and delimiting a storage volume powder. The casing also comprises second lateral walls 34 delimiting a volume in which the metering cylinder 22 is contained.

The layering device further comprises means for smoothing the dose of powder delivered by the powder deposition means 18. In this first embodiment of the invention, they comprise a smoothing roller 36.

The function of the smoothing roller 36 is, as it passes over the deposition zone P during advancement of the layering device, to distribute and smooth the dose of powder deposited by the powder deposition means 18.

The straightening cylinder 36 may be stationary or rotatable. In this case, the smoothing roller 36 is rotatable, and its rotation takes place in a direction opposite to that of the advance of the smoothing roller 36 due to the displacement of the layering device 14.

Thus, taking into account the orientation of FIG. 1, the layering device 14 moving in the direction of the arrow F (from the starting zone on the right of the figure to the arrival zone on the left of FIG. ), the smoothing roller 36 rotates clockwise.

It can be seen that since the powder used in powder-based additive manufacturing facilities is both volatile and sticky, the latter tends to accumulate and then agglomerate at various points in the setting device. in layer 14 during the powder deposition cycles.

In particular, it has been observed that powder accumulates and forms agglomerates 38 in the interstices between the powder deposition means 18 and the casing 30 of the layering device 14. FIG. 2 shows in particular that agglomerates 38 are formed between the second lateral walls 34 and the metering roll 22.

To remedy this, the installation 10 comprises a first cleaning device 40, located on the path of the layering device 14 upstream of the deposition zone P, considering the path in the direction of departure zone A towards zone d. arrival B.

The first cleaning device 40 comprises a first blowing device 42, visible more particularly in FIGS. 3 and 4, configured to blow a flow of gas on at least one surface of the powder deposition means 18. In this case, the gas blown by the blowing device is the ambient gas of the deposition zone P, here of the dinitrogen, but it could also be argon, hydrogen or another neutral gas.

The first blower device 42 includes orientation means 44 of the gas flow in a predetermined orientation direction. More particularly, the orientation means comprise a blast nozzle 46 provided with a plurality of aligned orifices 48, directed parallel to the predetermined orientation direction.

The predetermined direction of orientation is chosen so that the gas flow reaches a surface of the housing 30 facing the powder deposition means 18 during the course of the layering device 14.

Preferably, the predetermined direction of orientation is also such that the flow of gas reaches, during the course of the layering device 14, a surface of the metering roll 22, and a surface of the smoothing means 35 of the powder as the surface of the smoothing cylinder 36.

Thus, in the first embodiment shown in FIGS. 1 to 7, the predetermined orientation direction is chosen as being normal to the plane of the plate 12 and directed towards the layering device 14. This orientation direction is therefore perpendicular to the translation axis X of the layering device 14 and has a direction opposite to that in which the gravity is exerted.

The choice of such an orientation direction, represented by the arrows O in Figure 4, directs the flow of gas F from the orifices 48 to the surface of the second side walls 34 of the housing 30 located opposite the metering cylinder 22.

The orifices 48 are preferably aligned in a direction perpendicular to the translation axis X of the layering device 14 and to the orientation direction O. In this way, a flow of gas F from the orifices 48 reaches the surface of the metering roll 22 over all, or almost all, the longitudinal direction of the second side walls 34 of the housing 30.

This choice also makes it possible to reach the surfaces of the metering roll 22 and of the smoothing roller 36 during the course of the layering device 14.

More particularly, the distance that can be reached by the flow of gas F, as well as the speed of this flow F, will be adjusted so as to be able to dislodge the agglomerates 38 of powder located between the second lateral walls 34 and the metering roll 22, as may be possible. see it in figure 4.

The cleaning device 40 may also comprise sealing means 50 sealingly separating the powder from a first cleaning zone N1, where the flow of gas is blown on at least one surface of the powder deposition means 18, relative to at the deposit zone P of the powder.

Preferably, these sealing means 50 comprise at least one brush

52 provided with bristles 54 can bend over the passage of the layering device 14. The brush 52 separates the first cleaning zone N1, in which is located the first blowing device 42, the powder deposit zone P .

More particularly, as can be seen in FIG. 3, the length of the bristles 52 of the brush is chosen so as to provide a seal between the cleaning zone N1 and the zone of deposition of the powder P at the moment of the passage of the device. layer 14 in the first cleaning zone N1. For this purpose, the bristles 54 of the brush 52 extend in a direction perpendicular to the surface of the deposition means 18 of the powder with which they come into contact. Thus, the bristles extend in the same direction as the orientation direction O of the flow.

In addition, the bristles 52 of the brush are long enough to flush with one of the second side walls 34 of the housing 30 when the blowing nozzle 46 is in line with the metering cylinder 22 and thus perform its sealing function.

As a result, there will also be contact between the bristles 54 and the surface of the metering roll 22 and / or the smoothing roll 36 at the passage of the layering device 14 in the first cleaning zone N1. Thus, in addition to exerting a sealing function, the brush 52 can perform a function of brushing the surface of the metering roll 22 and / or the smoothing roll 36 to the passage of the layering device 14. This allows the dislodging the agglomerates of powder that may have accumulated on the surface of these metering cylinders 22 and straightener 36.

In the embodiment shown in FIGS. 1 to 7, the sealing means 50 comprise only one brush 52 located downstream of the cleaning zone N1 and the first blowing device 42. However, in a variant not shown, the sealing means 50 comprise two brushes 52, the cleaning zone being delimited by these two brushes 52 and the blowing device 42 being located between the two brushes 52. The second brush 52 will be in this case preferably identical to the first, and arranged symmetrically with respect to the direction of alignment of the orifices 42 (ie symmetrical with respect to the blowing nozzle 46).

Advantageously, to evacuate the agglomerates 38 dislodged by the first blowing device 42 before they reach the deposition zone of the powder P, the cleaning device 40 further comprises a first suction device 56. suction device 56 discharges the powder sucked by the first suction device 56 to an area of the installation, called first dedusting zone D1, which is isolated from the powder deposition area P.

In the first embodiment shown in FIGS. 1 to 7, the first suction device 56 comprises a first evacuation duct 58 situated under the first cleaning zone N1, which extends in a direction normal to the plane of the apron 12 and which is directed in a direction opposite to that of the layering device 14.

For the sake of clarity, the elements of the first suction device 56 other than the first exhaust duct 58 have not been shown.

Preferably, the first evacuation duct 56 is situated in line with the first blowing device 42, and in particular at the right of the blast nozzle 46, hence below it in FIG. 3. For example, the first exhaust duct 58 has a convergent shape in the opposite direction to the first suction device 56.

FIG. 5 shows a histogram of a cleaning cycle carried out during a manufacturing process according to the invention, comprising a cleaning step.

This manufacturing method comprises a cleaning step in which the layering device 14 performs a cleaning path on which the cleaning device 40 is located, the cleaning path being reciprocating.

For example, as shown in Figure 5 showing a histogram of a cleaning cycle, the layering device 14 performs three round trips in the cleaning path. It will therefore pass six times in the cleaning zone N1. On this occasion, there will be six times contact between the brush 52 and the metering cylinder 22 and the smoothing cylinder 36.

Preferably, the first suction device 56 performs its suction function during the entire duration of the cleaning step. It is preferably the same for the blowing device 42.

Furthermore, again as can be seen in the histogram of FIG. 5, during the cleaning step, the smoothing roller 36 is rotated, which facilitates the detachment of any agglomerates 38 of powder by the flow of gas F sent by the first blowing device 42. This rotation preferably takes place during the entire duration of the cleaning step.

In order to more specifically dislodge the agglomerates of powder that can accumulate on the surfaces of the smoothing roller 36 and / or the metering roll 22, the installation 10 comprises a second cleaning device 60, located downstream of the deposition zone P. .

This second cleaning device 60 comprises a brushing device 62 for brushing at least one surface of the smoothing means 35 of the powder, here that of the smoothing roller 36.

For this purpose, the brushing device 62 comprises at least one brush provided with bristles that can bend over the passage of the layering device 14.

In the embodiment shown in Figures 1 to 7, the second cleaning device 60 comprises in particular two parallel brushes extending in a substantially longitudinal direction, an upstream brush 64 and a downstream brush 66 (the upstream and downstream terms to be included in relation to the path of the layering device 14 from the departure zone A to the arrival zone B).

In the example shown in FIGS. 1 to 7, and as can be seen in particular in FIG. 6, the upstream brush 64 and the downstream brush 66 are placed in such a way that the layering device 14 moves locally. in a direction substantially perpendicular to the longitudinal direction of the brushes 64, 66.

In this case, the upstream brush 64 and the downstream brush 66 extend along an axis perpendicular to the translation direction X of the layering device 14.

Moreover, the bristles 68 of the upstream brush 64 and the bristles 70 of the downstream brush

66 extend in a direction perpendicular to the surface of the smoothing means 35 of the powder with which they come into contact, here smoothing cylinder 36.

The length of the bristles 68 of the upstream brush 64 and the bristles 70 of the downstream brush 66 are chosen so that the upstream brush 64 and the downstream brush 66 can brush the surface of the smoothing roller 36.

Preferably, the brushing device 62, and therefore the upstream brushes 64 and downstream brush 66, also brushes at least one surface of the powder deposition means 18, here that of the measuring cylinder 22. Furthermore, this brushing is advantageously carried out perpendicular to the surface of the metering roll 22.

In the example shown in FIGS. 1 to 7, the bristles 68 of the upstream brush

64 and the hairs 70 of the downstream brush 66 have the same length. However, in a variant not shown, the bristles of the two upstream brushes 64 and 66 downstream have different lengths to adapt to the dimensions of the metering roll 22 and the smoothing cylinder 36 when their diameters differ from each other, or so as to adapt to the different heights of the metering cylinder 22 and the smoothing roller 36 relative to the deposition zone P.

The second cleaning device 60 being placed downstream of the deposition zone P of the powder, the upstream brush 64 separates a second cleaning zone N2, where the brushing of the powder deposition means 18 takes place, from the deposition zone. P.

Thus, preferably, the length of the bristles 68 of the upstream brush 64 is chosen so as to provide a seal between the second cleaning zone N2 and the deposition zone of the powder P at the time of the passage of the layering device 14. in the cleaning area N2.

In this case, the bristles 68 of the brush are long enough to flush one of the second side walls 34 of the housing 30 when the blowing nozzle 46 is in line with the metering roll 22 and thus perform a sealing function to the powder as in the first cleaning device 40.

As in the first cleaning device 40, the second cleaning device 60 may comprise a powder suction device. This second suction device 72 of powder discharges the powder it aspires to a second dust collection zone D2 isolated from the powder deposition zone P.

For this purpose, the second suction device 72 comprises a suction nozzle 74 comprising a suction orifice 76 in the form of a slot with substantially rectangular edges made in the apron 12.

The suction port 76 constitutes the inlet of a discharge duct 78 connecting the cleaning zone N2 to the second dust collection zone D2.

Preferably, and as can be seen more particularly in FIG. 7, one of the two brushes of the brushing device 62, here the downstream brush 66, is placed at the edge of the suction orifice 76.

To better facilitate the evacuation of the powder sucked by the second suction device 72, the latter comprises means 80 for guiding the powder sucked to guide the powder towards the second exhaust duct 78.

These guide means 80 comprise in particular a ramp 82 located opposite the downstream brush 66, the wall 82P of the ramp being in facing relation to a wall 84P of the body 84 of the downstream brush 66 forming a duct. introduction of the powder to the rest of the exhaust duct 78.

In the example shown in Figures 1 to 7, the second exhaust duct 78 comprises a first portion 87 extending under the deck 12, in a direction parallel to the translation axis X of the layering device 14 .

Then, the second exhaust duct 78 comprises a second portion consisting of a discharge tube 88 extending in a direction normal to the plane of the apron 12. The first end of this tube 88 is connected to the first part 87 and the second end of this tube 88 is connected to the second dust removal zone D2, in which the aspirated powder falls under the effect of the suction and / or gravity.

In the same way as with the first cleaning device 40, an additive manufacturing process involving the second cleaning device 60 comprises a cleaning step in which the layering device 14 performs a cleaning path on which finds the second cleaning device 60, the cleaning path being alternative. Preferably, during this cleaning step, the smoothing roller 36 is rotated to better dislodge any agglomerates of powder using the upstream brushes 64 and downstream 66.

Note that in the first embodiment according to the invention shown in Figures 1 and 7, the installation 10 comprises a first 40 and a second device 60 cleaning, but it can quite understand only one both.

There is shown in Figures 8 and 9 a second unclaimed embodiment of the installation 10, the elements common to the previous embodiment are designated by similar references.

Like the installation of the first embodiment according to the invention, the installation 10 of the second embodiment not claimed includes a layering device 14 of the movable powder along a path connecting a starting zone A and a finish area B.

This layering device 14 comprises means 18 for depositing the powder for depositing powder in a deposition zone P of the powder located between the starting zone A and the arrival zone B.

In contrast, in this second embodiment not claimed, the powder deposition means 18 comprise, instead of a metering roll, a sliding drawer. These depositing means have not been shown in the figures.

Like the first and second cleaning devices, the third cleaning device 90 is situated on the path of the powder deposition device 14 and is provided with means for smoothing the dose of powder delivered by the powder deposition means. including a smoothing roller 36.

The installation of the second, unclaimed embodiment also includes a cleaning device, or third cleaning device 90, upstream of the powder deposit area P.

The third cleaning device 90 comprises scraper means 92 provided with a plurality of longitudinal scraping teeth 94, parallel to each other, scraping the surface of the smoothing roller 36 tangentially to this surface. In particular, the layering device 14 moves locally on the path in a direction substantially parallel to the longitudinal direction of the scraping teeth 94 of scraping means 92. In the example shown in FIGS. 8 and 9, the teeth scraping means 94 scraping means 92 thus extend along the axis X.

Preferably, the doctoring means 92 comprise at least one comb comprising the plurality of scraping teeth 94. The scraping teeth 94 of the comb are substantially all of the same length.

In this second embodiment not claimed, the scraping means 94 comprise a first comb 96 forming a first row of teeth 94 and a second comb 98 forming a second row of teeth 94, the first and second rows of teeth 94 being parallel.

In order to obtain a more effective scraping of the surface of the smoothing roller 36, the free ends of the teeth 94 of the first comb 96 are offset longitudinally with respect to the free ends of the teeth 94 of the second comb 98.

In this case, the first comb 96 and the second comb 98 share the same body 100. More particularly, the teeth 94 of the first comb 96 and the second comb 98 extend from the same plane, here the same surface 102 of the body 100.

On the other hand, the length of the teeth 94 of the first comb 96 is greater than the length of the teeth of the second comb 98.

In order to be durable, the teeth 94 of the doctoring means 92 are preferably made of metallic material.

More particularly, the teeth of scraping means 92 are made of demagnetized stainless steel, so as, on the one hand, to avoid the creation of oxides and the pollution of the powder by these oxides, and on the other hand to may be used in a metal powder additive manufacturing facility. An example of such a steel is, for example, demagnetized stainless steel 301.

In this second embodiment not claimed, as in the first embodiment, the cleaning device comprises a blowing device 42 configured to blow a flow of gas on at least one surface of the smoothing roller 36.

This blowing device 42 is very similar to that of the installation of the first embodiment, it will not be described in more detail here.

It will be specified only that in a similar manner to the first embodiment, this blowing device 42 comprises a blast nozzle 46 provided with a plurality of aligned orifices 48 directed towards the surface of the smoothing roller 36, and that the layering device 14 moves locally on the path in a direction substantially perpendicular to the direction of alignment of the orifices 48 of the blast nozzle 46.

In the same way as with the first cleaning device 40 or the second cleaning device 60, an additive manufacturing process involving the third cleaning device 90 comprises a cleaning step in which the layering device 14 performs a cleaning path on which the third cleaning device 90 is located, the cleaning path being reciprocating.

Preferably, during this cleaning step, the smoothing roller 36 is rotated to better dislodge any agglomerates of powder using the combs 96, 98 in a direction opposite to that of the advance of the smoothing cylinder 36 because of the displacement of the layering device 14. For example, the teeth 94 of scraping means 92 extending from upstream to downstream (from the right to the left in FIGS. 8 and 9), the setting device layer 14 moves downstream upstream and the smoothing cylinder 36 rotates counterclockwise during cleaning.

Note that in the second embodiment not claimed in Figures 8 and 9, the installation 10 includes a single cleaning device 90, but it can quite understand several, including one and / or the other of the first 40 and second 60 cleaning devices.

In general, the invention is not limited to the embodiments shown and other embodiments will become apparent to those skilled in the art.

For example, any combination of elements of the different cleaning devices described above may be considered.

Claims

A powder-based additive manufacturing plant (10) comprising a device (14) for laying the movable powder along a path connecting a starting zone (A) and an arrival zone (B). )

the layering device (14) comprising means for smoothing (35) the powder in a deposition zone (P) of the powder located between the starting zone (A) and the arrival zone (B),

characterized in that it further comprises a cleaning device (60) located on the path of the layering device (14), the cleaning device (60) comprising a brushing device (62) for brushing at least one surface of the smoothing means (35) of the powder.

2. Manufacturing plant (10) according to claim 1, wherein the cleaning device (60) comprises a suction device (72) powder for discharging the powder sucked by the suction device (72) to a zone of the installation, called the dedusting zone (D2), which is isolated from the powder deposit zone.

3. Manufacturing plant (10) according to any one of the preceding claims, wherein the brushing device (62) comprises at least one brush (64, 66) provided with bristles (68, 70) which can bend over the passage of the layering device (14).

4. Manufacturing plant (10) according to claims 2 and 3 taken together, wherein the brush (64,66) is placed at the edge of a suction port (76) of the suction device (72).

Manufacturing plant (10) according to claim 3 or 4, wherein the bristles (68,70) of the brush (64,66) extend in a direction perpendicular to the surface of the smoothing means (35) of the powder with which they come into contact.

The manufacturing apparatus (10) according to any one of claims 3 to 5, wherein, the brush (64,66) extending in a substantially longitudinal direction, the layerer (14) moves locally. on the path in a direction substantially transverse to the longitudinal direction of the brush (64,66).

A manufacturing plant according to any one of claims 3 to 6, wherein the cleaning device (60) comprises two parallel brushes (64, 66) extending in a longitudinal direction, the setting device layer (14) moving locally in a direction substantially perpendicular to the longitudinal direction of the brushes (64,66).

8. Manufacturing plant (10) according to any one of the preceding claims, wherein the cleaning device (60) is downstream of the deposit zone (P) of the powder, considering the course in the direction of the zone. from departure to arrival area.

A manufacturing plant (10) according to any one of the preceding claims, wherein, the powder smoothing means (35) comprising a smoothing roll (36), the brushing device (62) brushes the outer surface of the straightening cylinder (36).

10. Manufacturing plant (10) according to any one of the preceding claims, wherein the layering device further comprising means for depositing (18) the powder, the brushing device (62) brushes at least one surface of the depositing means (18) of the powder.

1 1. A manufacturing facility (10) according to claim 10, wherein, the powder deposition means (18) comprising a rotary metering roll (22), the brushing device (60) brushes the outer surface of the rotary metering roll (22). ).

12. A powder-based additive manufacturing process using a powder-based additive manufacturing facility (10), comprising a step of cleaning an element of the manufacturing facility (10),

characterized in that

the manufacturing plant (10) is according to any one of claims 1 to 11, and in that during the cleaning step the cleaning device (14) is provided with a cleaning path on which the cleaning device (90) is located, the cleaning path being reciprocating.

13. The manufacturing method according to claim 12 by means of a manufacturing facility (10) according to claim 9, wherein, during the cleaning step, the smoothing roller (36) is rotated.