FR3016549A1 - DEVICE FOR PRINTING IN THREE DIMENSIONS OF A PIECE - Google Patents

Abstract

The three-dimensional printing device (1) for a part to be produced comprises a printing nozzle (2) comprising a first die, an inductive means for heating (3,5) the printing nozzle and a means for feeding device (41) of die printing material, the device being arranged to implement a method of printing the part to be produced by depositing molten filament of printing material, and the printing nozzle having an element of ferromagnetic material (23) arranged to cooperate with the inductive means for heating the printing nozzle.

Description

The invention relates to a device for three-dimensional printing of a workpiece from a given material or set of materials.

Today, most three-dimensional printers use a molten filament deposition process. They are marketed and developed for rapid prototyping of parts or sets of parts. As a result, they use only a very limited range of materials. Finally, they use only simple plastic materials such as PLA (polyacetic acid) and ABS (acrylonitrile butadiene styrene) for example. These materials melt at temperatures between 200 ° C and 400 ° C. In order to melt these plastic materials, it is used heating cartridges. A high performance heating cartridge can heat up to 750 ° C. However, the melting temperature of the metals varies between 700 ° C. and 2300 ° C., see more. For example, it is very difficult to achieve the melting temperature of aluminum, of the order of 700 ° C, using such a system when the energy losses of the device are taken into account. An object of the invention is to provide a three-dimensional printing device which makes it possible to produce a part in any material that can be melted in a simple manner. For this purpose, according to the invention, there is provided a device for printing in three dimensions a part to be produced comprising a printing nozzle comprising a first die, an inductive means for heating the printing nozzle and means for supplying the die with printing material, the device being arranged to implement a method of printing the part to be produced by deposition of molten filament of printing material, and the printing nozzle comprising an element made of ferromagnetic material arranged to cooperate with the inductive means for heating the printing nozzle.

Thus, the use of a printing nozzle comprising an element made of ferromagnetic material makes it possible, by cooperation with an inductive means, to heat all the printing material in a simple and effective manner to the melting point. Advantageously, but optionally, the device according to the invention comprises at least one of the following additional technical characteristics: the element made of ferromagnetic material is in contact with an external peripheral surface of the printing nozzle, the nozzle of printing comprises a chamber arranged in an outer peripheral wall, the chamber comprising the element made of ferromagnetic material, the printing nozzle comprises at least one second die extending parallel to the first die, the device comprising two or more several printing nozzles, the device comprises as many inductive heating means as printing nozzles, each of the printing nozzles being associated with inductive means of dedicated heating, the inductive heating means comprises a coil of induction having a single turn or several turns, - the device comprises a magnetic shield means located between the inductive heating means and a printing end of the printing nozzle; the device further comprises machining means arranged to perform a finishing on the molten filament deposited by the printing nozzle, after cooling said fused filament, the device furthermore comprises means for cooling the inductive heating element and / or the means for supplying printing material; the device comprises a system for supplying fiber or wire so that to produce a part to be made of composite material, - the device comprises means for diffusing an inert gas arranged so as to create a controlled atmosphere around the printing nozzle and the part to be produced, - the device comprises in in addition to means for measuring a temperature at the output of the printing nozzle, the device comprises second means for measuring a temperature of a zone of the part to be produced on which the melted lament will be deposited by the printing nozzle, - the device comprises second heating means of an area of the workpiece to be made on which the molten filament will be deposited by the printing nozzle, - the device comprises a preheating system of a part already made of the part to be produced and comprising in particular a plate heated by an induction system, and - the device comprises a printing chamber defining a volume around the part to be produced, during a operation, whose temperature and / or atmosphere are controlled and controlled. Other features and advantages of the invention will appear in the following description of embodiments. In the accompanying drawings: FIG. 1 is a three-dimensional view of an embodiment of a three-dimensional printing device according to the invention; FIG. 2 is a three-dimensional partial view of the device of FIG. 1 comprising a first embodiment of a printing nozzle; FIG. 3 is a side view of a second embodiment of a printing nozzle that can be used on the device of FIG. 1; FIGS. 4A and 4B are partial three-dimensional views of two embodiments of inductive means that can be used with the device of FIG. 1; FIGS. 5A to 5C are side views illustrating a third embodiment of a printing nozzle for a three-dimensional printing device according to the invention; FIG. 6 is a partial side view of a first variant embodiment of a three-dimensional printing device according to the invention; FIG. 7 is a view from above of FIG. 6; FIG. 8 is a partial three-dimensional view of the device of FIGS. 6 and 7; FIG. 9 is a three-dimensional view of a second variant embodiment of a three-dimensional printing device according to the invention; FIG. 10 is a three-dimensional exploded view of an alternative embodiment of the printing nozzle of FIG. 3; FIG. 11 is a three-dimensional partial view of an alternative embodiment of the three-dimensional printing device according to the invention; FIG. 12 is a three-dimensional partial of another variant embodiment of the three-dimensional printing device according to the invention; FIG. 12A is an example of a part obtained with the device of FIG. 12; FIG. 13 is a schematic three-dimensional view of a heating plate intended to receive a part to be produced for a three-dimensional printing device according to the invention; FIG. 14 is a three-dimensional view of an embodiment of a printing enclosure for a three-dimensional printing device according to the invention; and, - Figure 15 is a three-dimensional partial view of another embodiment of a three-dimensional printing device according to the invention.

Referring to Figure 1, we will describe an embodiment of a three-dimensional printing device 1 according to the invention. The three-dimensional printing device 1 according to the invention comprises a printing head 4 of generally cylindrical shape, in particular cylindrical of revolution. From an upper end to a lower end, the print head is traversed longitudinally by a material supply duct 41 and optionally by at least one conduit for supplying a gas 42 which is inert with respect to the material used to the impression. Here, the head comprises two conduits for supplying a gas 42. On the other hand, the print head 4 may comprise cooling means comprising an inlet 43 and an outlet 44 of coolant. These cooling means may be in the form of a peripheral chamber partially surrounding the print head 4. According to an alternative embodiment, the print head 4 comprises several material supply ducts 41, for example between two and four supply ducts material 41. This allows to achieve, with a single three-dimensional printing device 1 according to the invention, a piece from several different materials. On the other hand, the three-dimensional printing device 1 according to the invention comprises an inductive means 3, 5 comprising an induction heating head 5 and an indication coil 3 connected to this induction heating head 5. The induction coil 3 comprises a loop 33 and two connectors 31 and 32 located at each end of the loop 33 and connecting the latter to the induction heating head 5. The loop 33 surrounds a printing nozzle 2 which is mounted on the lower end of the print head 4. The printing nozzle 2 comprises a nozzle body 21 which is connected to the lower end of the print head 4, via connection means, at the level of the material feed duct 41. The nozzle further comprises a nozzle head 22. The printing nozzle 2 is further traversed longitudinally by a die which extends when the printing nozzle 2 is mounted. on the lower end of the head 4, the supply duct 41 to one end of the nozzle head 22 at which the die opens. The nozzle body 21 comprises an element of ferromagnetic material 23 which here is located on an outer periphery of the nozzle body 21 and partially surrounds it. Once the printing nozzle is mounted on the print head 4, the ferromagnetic material element extends coaxially with respect to and away from the inside of the loop 33 of the induction coil 3. Here, the magnetic material member 23 is a ring attached to the nozzle body 21 and in contact with a peripheral surface of the nozzle body 21.

On the other hand, the three-dimensional printing device 1 according to the invention comprises a confinement element 7 which is mounted on the lower end of the print head 4. This confinement element delimits a volume around the printing nozzle in which the opening or ducts for supplying a gas 42. This makes it possible to establish a controlled atmosphere volume for the deposition of molten filament material which will constitute the part to be produced. In an alternative embodiment, the confinement element 7 comprises a system for capturing the gases resulting from the melting of the printing material used to produce the part, as well as the gas injected by the gas supply ducts. The capture system cooperates with filtration and recycling means in order to eliminate the gases resulting from the melting of the injected gas for reuse of the latter via the gas supply pipes 42. Thus the quality of the controlled atmosphere is improved within the volume placed under this controlled atmosphere and delimited by the confinement element 7.

The three-dimensional printing device 1 according to the invention further comprises means for controlling and regulating an ejection temperature 6.8 at an outlet of the nozzle head 22. Here, the means method for controlling and regulating a temperature comprises a laser aiming pyrometer 6, forming a first temperature sensor, mounted on a carrier arm 8 extending centrifugally from the print head 4 of the printing device in three dimensions 1 according to the invention. In a variant, the laser aiming pyrometer is mounted outside a printing zone and is connected to the three-dimensional printing device according to the invention via communication means such as an optical fiber for example. This variant makes it possible to load less masses onto the printing head of the three-dimensional printing device according to the invention.

Such an alternative embodiment is illustrated in FIG. 15, where the laser aiming pyrometer is not shown, the measurement being carried out through an optical fiber 60 of which a free end 61 is oriented towards the nozzle head. A support 45 provided on the print head 4 keeps in place the optical fiber 60.

In an alternative embodiment, the means for controlling and regulating a temperature comprise a thermocouple. In order to regulate the temperature of ejection of molten material intended to produce the part, the means for controlling and regulating a temperature act, on the one hand, on the operation of the induction heating head 5 of the inductive means which pilot a magnetic field emitted by the induction coil 3 and, secondly, the operation of the cooling means of the three-dimensional printing device 1 according to the invention. In another variant embodiment, as illustrated in FIG. 15, the means for controlling and regulating a temperature comprise a second temperature sensor 575, 576, such as a laser aiming pyrometer, a signal of which can be transmitted to the printing device in three dimensions according to the invention by an optical fiber 575. This second temperature sensor is arranged so as to be able to record a temperature of the previous layer of the part to be made at a place which will receive molten material ejected by the nozzle of impression 2 for producing the next layer of the part to be produced. This temperature reading at this point of the previous layer will make it possible to control a delta-T temperature difference between the previous layer already produced and the next layer being produced in order to optimize a weld between these two layers. This makes it possible to adjust the temperature of ejection of molten material by the printing nozzle 2 (thus to adjust a heating temperature of said printing nozzle 2), possibly to adjust an amount of inert gas supply. against the printing material used (via the supply ducts 42) or to vary the amount of molten printing material ejected by the printing nozzle and deposited on the previous layer to obtain a layer-to-layer adhesion that is optimal and identical over the entire piece to be made. In one embodiment, this second temperature sensor is removably mounted on the three-dimensional printing device 1 according to the invention. It is controlled, on the other hand, according to a displacement of the print head 4, therefore according to a displacement of the printing nozzle 2, so as to have a "time" ahead of this, to raise the temperature at a place of the previous layer, just before this place receives a quantity of molten material ejected by the printing nozzle 2. In the embodiment of Figure 15, the second sensor of temperature comprises a remote laser aiming pyrometer and not shown which raises a temperature at a given point of the previous layer already made 511 through an optical fiber 575, mounted on the support 45 of the print head and a free end 576 is oriented towards the zone of the previous layer already carried out 511, a temperature to be recorded. In another embodiment, the three-dimensional printing device according to the invention comprises a second heating system 570 of inductive nature (as illustrated in FIG. 15) or resistive, arranged so as to allow the previous layer to be preheated. already performed 511 at a desired temperature. This second heating system can be positioned in the same way as the second temperature sensor 575, 576 in order to have a "time" ahead of the print head 4, like the second temperature sensor. Here, the second heating system 570 is similar in structure to the preceding inductive means 3, 5. It therefore comprises an induction heating head, not shown but which may be the previous heating head 5, and an indication coil 570 connected to this induction heating head. The induction coil 570 comprises a loop 571 and two connectors 572 and 573 located at each end of the loop 571 and connecting the latter to the induction heating head. The loop 571 extends facing and near an area to be preheated by the previous layer 511. In a further embodiment, illustrated in FIG. 13, the three-dimensional printing device according to the invention comprises a plate 550 on which is performed, during a print, the part to achieve. This plate 550 comprises heating means 551,552 of inductive type to form an induction plate, for example. Thus, this makes it possible to preheat the part already made of the part to be produced, in particular the preceding layers made in order to optimize the welding between the different layers of the part to be produced all along the printing of the part to be produced by the three-dimensional printing device according to the invention. The heating means comprise an induction coil 551 located on the plate 550 and connected to a control box 552.

In another additional embodiment, illustrated in FIG. 14, the three-dimensional printing device according to the invention comprises a printing enclosure 560 delimiting a volume 566 in which the part to be produced is printed, during a operation of the three-dimensional printing device according to the invention. This printing enclosure 560 makes it possible to control and control the temperature of said volume in the manner of a rotary heat oven known per se. In addition, the conduits for supplying a gas 42 open into the printing chamber 560 to control and control the atmosphere. Here, the printing enclosure 560 includes one or more heating resistors 561 of the volume 566 as well as means 565 for mixing the atmosphere of the volume 566, such as one or more mixing fans 565. The resistors 561 and the fans 565 are placed in a ventilation and heating box 563 located on one side of the printing chamber 560 and for directing the part of the atmosphere sucked by the fans 565 to and through the resistors 562 before reinjection into the In addition, 562 and 564 outlet temperature control means are provided on the box 563. Referring now to FIG. 3, a second embodiment of a nozzle of FIG. printing of the three-dimensional printing device according to the invention. According to this embodiment, the printing nozzle 200 comprises a nozzle body 210 and a nozzle head 220. The printing nozzle is traversed by a die 214 extending longitudinally from a first end 211 to a second opposite end 221. The nozzle body 210 includes a first portion 212 having connection means with the end of the print head 4 of the three-dimensional printing device 1. These connecting means comprise, here, a thread . This first portion 212 is extended towards the nozzle head 220, here by a second intermediate portion which comprises a conduit 213 oriented radially and opening, on one side, in the die 214 and, on the other side, at the level of a radially outer periphery of the second part. This allows, in the presence of a controlled atmosphere volume around the printing nozzle 200, a supply of inert gas for the printing material used from this volume to the die 214. Then, the second part of the nozzle body 210 extends, always in the direction of the nozzle head 220, by a third portion which comprises a chamber 230 which is arranged so as to surround a portion of the die 214. This chamber 230 is made in a thickness of the third part surrounding the die 214. Here, the chamber 230 is annular and coaxial with the die 214. In addition, the chamber 230 is hermetic, once the printing nozzle 200 is constituted. An element made of ferromagnetic material is positioned in this chamber 230. Such an arrangement makes it possible to no longer be held by the melting temperature of the ferromagnetic material used to produce this element, unlike the embodiment of the printing nozzle illustrated in FIGS. and 2. The element made of ferromagnetic material is confined in the chamber 230 whether it is in the solid state or in the liquid state. It is then possible to use any printing material, especially those with higher melting temperatures than the ferromagnetic material used to make the element. On the third part of the nozzle body 210, is positioned the nozzle head 220 in which the die 214 extends to the second end 221 and where the molten material in the third part is ejected to make a layer in progress of the piece to realize. It should be noted that the printing nozzle 200 which has just been described is adaptable to all the embodiments of the three-dimensional printing device according to the invention which are described in this description text.

An embodiment variant 400 of this printing nozzle 200 is illustrated in FIG. 10. The printing nozzle 400 comprises two parts 410 and 420 connected to one another by connecting means 423, here in the form a thread. The upper part 410 comprises the first end 411 of the printing nozzle 400 as well as the connection means 412 to the print head 4 of the three-dimensional printing device 1 according to the invention. The lower part 420 has the second end 421 at the nozzle head. The portion 420 further comprises a chamber 430 arranged in a thickness of the portion 420 coaxially with the die 414. A radially transverse wall 435 intersects the chamber 430.

Finally, the chamber 430 is open at an upper end of the portion 420. This arrangement of the chamber 430 allows to introduce, when mounting the printing nozzle 400, a ferromagnetic material member 431 in the form of a ring split longitudinally by a slot 433. The closure of the chamber 430 is then effected by a sealing ring 432 which is semi-slotted longitudinally by a slot 434 which extends along a generatrix on a part of a wall The slots 433 of the element made of ferromagnetic material and 434 of the sealing ring are arranged to receive the transverse wall 435 during an assembly of the printing nozzle 400. Again, it should be noted that the printing nozzle 400 which has just been described is adaptable to all the embodiments of the three-dimensional printing device according to the invention which are described in this text of FIG. description. With reference to FIGS. 5A to 5C, we will describe a third embodiment of a printing nozzle of a three-dimensional printing device according to the invention. According to this embodiment, the printing nozzle 250 is in two parts: a nozzle head 270 and a nozzle body 260. The particularity of this printing nozzle 250 is the presence of two dies 264 and 265 extending longitudinally through the nozzle. minus the nozzle body 260. This printing nozzle 250 is for a print head 4 having two feed conduits 41 of printing material. The nozzle body 260 comprises connecting means 262 on the print head 4 of the three-dimensional printing device according to the invention, here in the form of a thread. At a low end, the nozzle body 260 comprises a cavity 261 having an internal thread and into which the dies 264 and 265 open. On an outer wall 263 surrounding at least this cavity 261, the nozzle body 260 can receive an element of ferromagnetic material similar to the printing nozzle 2 of Figures 1 and 2. In alternative embodiments, a chamber similar to the chamber 230 or the chamber 430 is arranged in the thickness of the wall of the body of nozzle nozzle 260 surrounding the cavity 261. The nozzle head 240 comprises, at an upper end, an external thread 273 intended to cooperate with the thread of the cavity 261 of the nozzle body 260 and an internal volume 272, here of frustoconical shape, donations a bottom is extended by a single die 274 opening at an end 271 of ejection of molten material. Once the nozzle head 270 is mounted on the nozzle body 260, the cavity 261 and the internal volume 272 define a melting chamber in which the dies 264 and 265 open, on the one hand, and the second, the die 274. The melting chamber is then surrounded by the element made of ferromagnetic material. Such an arrangement makes it possible to print a part to be produced using two different printing materials, and one and the same printing nozzle 250, or to prepare in the melting chamber a composite material composed of the two materials introduced via the 264 and 265 dies to achieve a composite material part. It should be noted that the printing nozzle 250 which has just been described is adaptable to all the embodiments of the three-dimensional printing device according to the invention which are described in this description text. The set of parts, apart from the element made of ferromagnetic material, forming the various printing nozzles 3, 200, 250, 400 that have just been described is made of non-ferromagnetic material, possibly of refractory type. For example, it may be silicon nitride, boron carbide, molybdenum or tungsten, etc. The printing material may be in the form of wire or powder. . With reference to FIG. 4A and FIG. 4B, we will now describe an embodiment of an induction coil 3, and an embodiment variant 300, of a three-dimensional printing device according to FIG. 'invention. In the embodiment of FIG. 4B, also visible in FIGS. 1 and 2, the induction coil 3 comprises a single-turn loop 33 connected to input connector 31 and output 32 elements of the loop 33 at the Induction heating head 5. As an alternative embodiment illustrated in Figure 4A, the induction coil 300 comprises a loop 330 multi turns (here numbering 2.5) connected to the input connector elements 310 and output 320 of the loop 330 to the induction heating head 5. In both cases, the loop 33, respectively 330, and the connector elements 31,32, respectively 310,320, are made using hollow tubes of any section in which a circulation R of cooling fluid of the induction coil 3, respectively 300, is carried out if necessary. Here, the section of the hollow tubes is circular. The shape of the turns is here circular. In variants, the shape of the turns is rectangular, or oval, or polygonal, if any. It should be noted that the induction coil 3,300 which has just been described is adaptable to all the embodiments of the three-dimensional printing device according to the invention which are described in this description text. In order to protect the inductive field generated by the loop of the induction coil from the already deposited layers of the part to be produced by the printing nozzle of the three-dimensional printing device according to the invention, the latter comprises magnetic shield means positioned between the loop of the induction coil and the previous layers of the part to be made already deposited. An exemplary embodiment of these magnetic shield means is illustrated in FIG. 11. They are here in the form of a circular disk 9 made of ferromagnetic material mounted on the printing nozzle 2, downstream of the nozzle head 22. A plane of the disk 9 is perpendicular to a longitudinal axis of the printing nozzle 2. In addition, it has a diameter which is greater than or equal to a diameter of a circle in which the loop 33 of the coil is inscribed. In operation of the three-dimensional printing device according to the invention, the inductive magnetic field generated by the induction coil does not affect the previous layers, and in particular the last previous layer, already made. However, the disk 9 makes it possible to heat the last previous layer already produced by thermal radiation without the inductive magnetic field generated by the induction coil disturbing the assembly of the layer being deposited by the printing nozzle and from the last previous layer already performed. Now, with reference to FIGS. 6 to 8, we will describe an alternative embodiment of the three-dimensional printing device according to the invention. In this variant embodiment, the three-dimensional printing device according to the invention comprises an induction coil 3 as previously described and a series 280 of printing nozzles 2 positioned on a support 281 made of ferromagnetic material. The series 280 of nozzles 2, here four in number, is positioned regularly or randomly on the support 281 which then serves as an element of ferromagnetic material. Each of the printing nozzles 2 of the 280 series has its own die 24. They are mounted on the lower end of the print head 4 of the three-dimensional printing device according to the invention, which then comprises as many supply ducts 41 than print nozzles of the 280 series, here four. Each of the supply ducts 41 is connected to a die 24 of a printing nozzle 2 of the 280 series. Such an arrangement makes it possible to produce three-dimensional impressions of parts to be produced by deposition of melt using simultaneously or alternatively several different materials, as well as printing nozzles 2 in the 280 series.

Thus, it is possible to make a composite part or a piece composed of different materials and colors. In Figure 9 is illustrated another embodiment of a three-dimensional printing device according to the invention. The three-dimensional printing device 100 comprises a support plate 101 on which are mounted an induction heating head 102, on the one hand, and, on the other hand, a series of printing heads 4, here in number four. Each print head 4 has at its lower end a printing nozzle 2 associated with an induction coil 3. Each assembly consisting of a print head 4, its printing nozzle 2 and its coil of Associated induction 3 is similar to the three-dimensional printing device 1 previously described in FIGS. 1 and 2. The induction coils 3 are connected to the induction heating head 102 which has a function similar to the heating head by induction 5 previously described. The number of printing heads 4 may vary as well as their arrangement on the support plate 101. As for the embodiment of FIGS. 6 to 8, the embodiment of FIG. 9 makes it possible to produce three-dimensional prints of parts. to be made by depositing melt using simultaneously or alternatively several different materials, as well as printing nozzles 2 in the 280 series. Thus, it is possible to produce a composite part or a piece composed of different materials and colors .

With reference to FIG. 12, according to one variant, the three-dimensional printing device according to the invention comprises a system for supplying thread or fibers 500. Equipped with such a system, the printing device in three dimensions according to the invention makes it possible to manufacture and to produce composite materials such as that illustrated in FIG. 12A. The yarn or fibers 510 supplied by the delivery system 500 is deposited on the previous layer 511 of printing material and then covered by the current layer 512 made by ejection of molten printing material by the printing nozzle 2 The deposition of the wire or fibers 510 can be done in all directions by superimposing or not (rectilinear deposit, crossed, twisted, etc ...). The delivery system 500 comprises a housing 501 comprising drive means 505 of the wire or fibers 510 through the housing 501. The drive means 505 are here in the form of drive rollers. The delivery system 500 comprises at the output of wire or fibers 510 cutting means, here in the form of a cutting blade 502, wire or fibers length. Finally, the delivery system 500 comprises means for guiding and depositing the wire or fibers 510 on the previous layer 511. These guiding and depositing means here comprise a roller 504 which can guide the wire or the fibers 510 mounted on the end of an arm 503. The roller 504 is positioned facing the printing nozzle 2. The delivery system 500 can be multiplied on the same three-dimensional printing device according to the invention to allow the production of parts with several types of wire or different fibers 510 at the same time, if necessary. The use of a three-dimensional printing device according to the invention which has just been described to the possibility of manufacturing batteries or super capacitors from graphene or with suitable composite materials for this type of embodiment. According to another embodiment, the three-dimensional printing device according to the invention which has just been described comprises machining means for the layer which has just been produced before the deposition of the next layer begins. . These machining means may comprise a milling machine. This makes it possible to obtain a better finish and a better accuracy of the part to be made. For this purpose, the production of the part alternates the deposition of a layer of molten printing material and the machining of this layer. In a variant, machining is performed on the finished part. The three-dimensional printing device according to the invention which has just been described can be used with the various existing three-axis printers: either a printer displacing the printing nozzle (s) on the x and y axes, and the plate support of the part to be made on the z axis (said vertical); a printer moving the printing nozzle or nozzles on the z axis (said vertical), and the support plate of the part to be made on the x and y axes; either the support plate of the part to be produced is fixed, and the printing nozzle or nozzles move on the three axes (x, y and z); either or the printing nozzles are fixed, and the support plate of the workpiece to move on the three axes (x, y and z). The three-dimensional printing device which has just been described can also be used on as many working axes as possible from the moment the start of the workpiece has a fixed point. It can be mounted on the end of a multi-axis robot arm. On the other hand, the part to be produced can be prepared by the three-dimensional printing device according to the invention by using a support material made of silica which serves as a support for the constrained parts of the part to be produced. The brittle nature of the silica allows easy removal of the support once the printing of the part to be completed. On the other hand, the part to be produced can be made from a polymer material loaded with fine particles or fibers made of ferromagnetic element (iron nickel and cobalt, for example). As a result, the second heating system of the preceding layer already produced makes it possible to preheat this previous layer to a desired temperature in order to obtain the best possible adhesion between this previous layer and the layer being deposited by the printing device. in three dimensions according to the invention.

Of course, it is possible to bring to the invention many modifications without departing from the scope thereof.

Claims (17)

REVENDICATIONS1. Three-dimensional printing device (1; 100) of a workpiece comprising a printing nozzle (2; 200; 250; 400) comprising a first die (24; 264,265,174; 414), inductive heating means (3,5; 102; 300) of the printing nozzle and a supply means (41) of printing material of the die, the device being arranged to implement a method of printing the workpiece. by depositing molten filament of printing material, characterized in that the printing nozzle comprises an element made of ferromagnetic material (23; 230; 281; 433) arranged so as to cooperate with the inductive means for heating the nozzle; 'impression. 2. Device according to claim 1, characterized in that the element of ferromagnetic material (23; 281) is in contact with an outer peripheral surface (263) of the printing nozzle. 3. Device according to claim 1 or 2, characterized in that the printing nozzle (200; 400) comprises a chamber (230; 430) arranged in an outer peripheral wall, the chamber comprising the element made of ferromagnetic material. 4. Device according to one of claims 1 to 3, characterized in that the printing nozzle (250) comprises at least a second die (264,265) extending parallel to the first die. 5. Device according to one of claims 1 to 4, characterized in that it comprises two or more printing nozzles (2; 280). 6. Device according to claim 5, characterized in that it comprises as many inductive heating means (3) as printing nozzles (2), each of the printing nozzles being associated with inductive means of dedicated heating. 7. Device according to one of claims 1 to 6, characterized in that the inductive heating means comprises an induction coil (3; 300) having a single turn (33) or several turns (330). 8. Device according to one of claims 1 to 7, characterized in that it comprises a magnetic shield means (9) between the inductive heating means and a printing end of the printing nozzle. 9. Device according to one of claims 1 to 8, characterized in that it further comprises machining means arranged so as to achieve a finish on the molten filament deposited by the printing nozzle, after cooling said filament. molten. 10. Device according to one of claims 1 to 9, characterized in that it further comprises cooling means (43,44, R) of the inductive heating element and / or the material supply means printing. 11. Device according to one of claims 1 to 10, characterized in that it comprises a fiber supply system or wire (500) so as to produce a part to be made of composite material. 12. Device according to one of claims 1 to 11, characterized in that it comprises means for diffusing an inert gas (7,42) arranged to create a controlled atmosphere around the printing nozzle and of the piece to realize. 13. Device according to one of claims 1 to 12, characterized in that it further comprises means for measuring a temperature (6; 60,61) at the output of the printing nozzle. 14. Device according to claim 13, characterized in that it comprises second means for measuring a temperature (575.576) of a zone of the part to be produced on which the molten filament will be deposited by the printing nozzle . 15. Device according to one of claims 1 to 14, characterized in that it comprises second heating means (570) of a zone of the part to be produced on which the molten filament will be deposited by the nozzle of impression. 16. Device according to one of claims 1 to 15, characterized in that it comprises a preheating system (550) of a part already made of the part to be produced and comprising in particular a plate heated by an induction system. 17. Device according to one of claims 1 to 16, characterized in that it comprises a printing chamber (560) defining a volume (566) around the workpiece, during operation, whose temperature and / or the atmosphere are controlled and mastered.