Apparatus and method for additive manufacturing of three-dimensional objects

Abstract

The invention relates to a device for additive manufacturing of all or part of a three-dimensional object (106) on a manufacturing support (104), comprising at least one additive deposition track (20, 30) intended to be arranged above the manufacturing support (104), extending along a longitudinal axis (X) and comprising a plurality of material deposition nozzles, each of the material deposition nozzles is provided with at least one dispensing orifice, each of the material deposition nozzles comprising a closing device movable between a closed position of the dispensing orifice and a plurality of open positions and an actuator for controlling the movement of the closing device between the closed position and the open position, the closing devices can be controlled independently of one another. The apparatus comprises at least one actuation system configured to produce a relative translation of the material deposition arrangement with respect to the manufacturing support (104) in at least one vertical direction (Z) and / or longitudinal direction (X).

Description

Field of the Invention

[0001] The present invention relates to the field of manufacturing three-dimensional objects. Background Art

[0002] It is known practice to use plastic injection moulds to produce three-dimensional objects from plastic.

[0003] Although this manufacturing method enables the production of a large number of three-dimensional objects, the prefabrication of the injection mould increases the manufacturing time of the three-dimensional objects.

[0004] Methods for depositing materials are also known, in which three-dimensional objects are produced by spraying individual droplets and then subjecting the droplets to photocrosslinking. However, the generation of individual droplets results in three-dimensional objects of unsatisfactory quality due to insufficient mechanical strength of the components. In addition, the printing time is very long.

[0005] In the case of PolyJet material deposition, the problem is particularly related to the choice of materials (which is limited by the requirement that the materials must be suitable for ultraviolet crosslinking).

[0006] Additive manufacturing by extrusion of molten material (which is known as fused deposition modelling or FDM) is also known.

[0007] It is known practice to use an extruder to produce a strip or line of molten material from filaments or granules made of thermoplastic material or composite material.

[0008] However, current methods are particularly slow because, before depositing the material at the nozzle, a support has to be positioned in a given orientation and this operation has to be repeated until the three-dimensional object is completely manufactured. Such a solution can only deposit a few tens of grams per hour, for example 50 g / hr.

[0009] In addition, the slow manufacture of the tread may lead to seepage problems.

[0010] In this regard, reference may be made to FR-B1-3067281, which proposes a system for manufacturing the tread of a tubeless integral wheel. The device includes a construction robot, which includes one or more nozzles for additive deposition. The nozzles are arranged side by side and are capable of lateral movement so that they can cover the entire tread to be constructed.

[0011] In order to reduce the manufacturing time of three-dimensional objects, a large extruder can be provided with a material deposition nozzle of 5 mm to 10 mm. However, in this case, although the material deposition rate is higher, about 900 g / hr, the accuracy is significantly reduced.

[0012] Therefore, none of the proposed solutions is satisfactory because a choice has to be made between the speed of manufacturing the three-dimensional object and the quality of the details or geometry of the said three-dimensional object.

[0013] In order to obtain a high material deposition rate and at the same time maintain a satisfactory quality of the geometry of the three-dimensional object, a large number of extruders can be used, for example, extruders between 100 and 200, each extruder having its own path. However, from the perspective of the occupied space and manufacturing cost, it is not conceivable to arrange about one hundred robotic arms each including an extruder and arranged around the three-dimensional object.

[0014] Therefore, there is a need to improve the device for manufacturing a three-dimensional object. Summary of the Invention

[0015] The object of the present invention is to rapidly manufacture a three-dimensional object and at the same time maintain the quality of the details of the three-dimensional object.

[0016] Therefore, the object is to reduce the manufacturing time of the three-dimensional object, so as to deposit a larger amount, about 10 kg / hr, in a short time.

[0017] The present invention relates to a device for additive manufacturing of all or part of a three-dimensional object on a manufacturing support.

[0018] "Additive manufacturing" means a manufacturing method carried out by the addition of extruded material (which is called fused deposition modeling or FDM).

[0019] The additive manufacturing device includes at least one additive deposition track, which is adapted to be arranged above the manufacturing support and includes a plurality of material deposition nozzles.

[0020] Each of the material deposition nozzles is provided with at least one dispensing hole.

[0021] Each of the material deposition nozzles includes a closing device and an actuator, the closing device being capable of moving between a closed position of the dispensing hole and a plurality of open positions, the actuator being used to control the movement of the closing device between the closed position and the open position, and the closing devices being capable of being controlled independently of each other.

[0022] Therefore, each of the material deposition nozzles is configured to deposit molten material on the manufacturing support, in particular on the receiving surface, in a plurality of material deposition sequences.

[0023] The "open position" of the dispensing hole means the fully open position of the dispensing hole and the intermediate position where the dispensing hole is partially open.

[0024] The opening of the dispensing hole can advantageously depend on the material deposition rate. Controlling the opening of the dispensing hole makes it possible to manage the material deposition rate by changing the position of the closing device (in particular the needle).

[0025] The material deposition nozzles can be identical or different from each other in terms of dimensions (such as the diameter of the dispensing orifice, the height of the material deposition nozzle, or the external dimensions).

[0026] The additive manufacturing device further comprises at least one actuation system configured to produce a relative translation between the material deposition track and the manufacturing support in at least the vertical direction and / or the longitudinal direction.

[0027] When the material deposition track moves, all the material deposition nozzles thus move simultaneously due to the movement of the material deposition track.

[0028] The dispensing orifices of each nozzle can be closed independently of one another and in a responsive manner, so that any detail can be manufactured on the circumferential support surface of the manufacturing support in a short time.

[0029] The three-dimensional object is manufactured by depositing and extruding the material layer by layer. The extruded material melts on the previously deposited material layer and solidifies when the temperature drops.

[0030] The longitudinal direction is parallel to or coincides with the longitudinal axis of the track.

[0031] Advantageously, the additive manufacturing device comprises at least one extruder connected to the material deposition track and supplying a wire of molten material to the track.

[0032] For example, the extruder is associated with all the material deposition nozzles.

[0033] For example, the extruder is located centrally. As a variant, a location other than the central location can be envisaged for the extruder.

[0034] A single central extruder makes it possible to reduce the space occupied around the manufacturing support and to lower the manufacturing cost.

[0035] As a variant, at least one extruder associated with at least one material deposition nozzle can be provided.

[0036] For example, a plurality of extruders can be provided, each extruder being associated with at least two material deposition nozzles.

[0037] For example, the wire of molten material can be obtained from granules.

[0038] The granules of the material are made of, for example, plastic (such as thermoplastic (TP) or thermoplastic elastomer (TPE)). Thus, the granules of the material are thermally extruded.

[0039] As a variant, the wire of molten material can be obtained from one or more filaments, or even strips. The wire of molten material can be segmented or continuous.

[0040] Preferably, the molten material line is continuous rather than in the form of continuous droplets, thereby avoiding any defects in the geometry of the object.

[0041] Advantageously, each material deposition nozzle includes a chamber for receiving molten material from an extruder, the chamber communicating with a dispensing orifice.

[0042] The dispensing orifice has a size, for example, between 0.6 mm and 1.5 mm, preferably between 0.6 mm and 0.8 mm (for producing a 1 mm wide material deposit), and preferably between 1 mm and 1.5 mm (for producing a 2 mm wide material deposit).

[0043] For example, the dispensing orifice of each material deposition nozzle has a rectangular or circular cross-section. A rectangular cross-section makes it possible to improve the level of detail of the geometry of the three-dimensional object and the quality of the interruption achieved by the closing device.

[0044] For example, the additive manufacturing device includes a fixed support and one or more material deposition rails that are translatably mounted relative to the fixed support.

[0045] For example, the additive manufacturing device includes at least two material deposition rails, each material deposition rail being associated with a dedicated actuation system and arranged at two given lateral positions above the manufacturing support.

[0046] The closing frequency of the temporary closing device is, for example, between 10 Hz and 30 Hz, for example equal to 20 Hz.

[0047] According to one embodiment, each of the temporary closing devices includes a needle.

[0048] As a variant, other closing devices can be provided, such as a sliding closing device or any other type of closing device configured to close or open the dispensing orifice.

[0049] The actuator includes, for example, a piezoelectric device for closing or opening the dispensing orifice of the corresponding nozzle.

[0050] It is also conceivable to use a pneumatic cylinder, a magnetic cylinder, an electric cylinder or a hydraulic cylinder to close or open the dispensing orifice of the corresponding nozzle.

[0051] The needle-type closing device makes it possible to cause a clean interruption of the flow of the molten material (without burrs) and an unobstructed resumption of said flow. As a variant, any other closing system associated with each nozzle can be provided, such as a valve.

[0052] The additive manufacturing apparatus may include a volumetric metering device disposed downstream of the extruder and upstream of the material deposition track. For example, the volumetric metering device is a gear pump. The volumetric metering device is configured to deliver a calibrated amount of molten material onto the support surface of the build support. Thus, a material line having a constant width can be obtained.

[0053] The volumetric metering device enables the amount of extruded material deposited to be repeatedly controlled throughout the manufacturing of the object. Controlling the amount of extruded material also enables waste of material that is not necessary for manufacturing the object to be limited.

[0054] According to one embodiment, at least one material deposition nozzle is configured to deposit material across all thicknesses of at least one lateral material line.

[0055] Depositing material in a "material line" means that if the object to be manufactured is a parallelepiped, the material is deposited on the support surface of the build support along an axis perpendicular to the longitudinal axis (e.g., the lateral axis), or if the object to be manufactured is a cylinder, the material is deposited on the support surface of the build support along a circular path.

[0056] "Thickness" means the layer of material deposited on a lateral or circular material line.

[0057] According to one embodiment, the material deposition nozzles are arranged in a single row along the longitudinal direction on the material deposition track.

[0058] In this case, all the material deposition nozzles are configured to deposit material layers in a material deposition sequence, optionally while the receiving support moves in the forward direction, and the material deposition track is configured to perform a relative translation along a vertical axis after each deposition of a material layer.

[0059] If the object to be manufactured is a shape other than a parallelepiped or a cylinder, the "forward direction" means the lateral direction, or if the object to be manufactured is a cylinder, the "forward direction" means rotation about the longitudinal axis.

[0060] Generally, the forward direction of the build support is perpendicular to the extension axis of the track, e.g., the longitudinal axis.

[0061] Thus, each of the material deposition nozzles is configured to deposit molten material in a corresponding material line according to the material deposition sequence, and after each material deposition sequence, i.e., after each material layer is manufactured, the material deposition track is configured to perform a relative translation along the vertical axis relative to the build support, and so on until the desired three-dimensional object is obtained.

[0062] "Material layer" means all the material lines side by side over the entire width of the three-dimensional object to be manufactured. The material layer corresponds to the thickness of the deposited molten material. On the material layer, it is possible to arrange for no material to be deposited on one or more lines in order to produce a specific geometry of the object to be manufactured.

[0063] If the object to be manufactured is a cylinder, the layer corresponds to all the circumferential lines.

[0064] As a variant, if the object to be manufactured is a parallelepiped or generally a non-cylindrical shape, the layer corresponds to all the transverse lines.

[0065] "Row" means an arrangement along the longitudinal axis. The rows are arranged over the width of the object to be manufactured.

[0066] The "width" of the object to be manufactured means the dimension along the longitudinal axis. The width can also be the dimension along the transverse axis. Generally, the width of the object to be manufactured corresponds to the extension dimension of the track.

[0067] The material deposition track can be configured to translate along a vertical axis relative to the manufacturing support. As a variant, the material deposition track can be fixed relative to the support of the manufacturing device, and the manufacturing support is configured to translate along a vertical axis relative to the material deposition track.

[0068] According to one embodiment, the additive manufacturing device includes a member for driving the manufacturing support, the member being capable of driving the manufacturing support in the forward direction.

[0069] According to one embodiment, the material deposition nozzles are arranged in at least two rows offset along a transverse axis perpendicular to the longitudinal direction and perpendicular to the vertical direction on the material deposition track, each row including at least two material deposition nozzles aligned along the longitudinal direction.

[0070] In other words, the rows are parallel to each other.

[0071] In each material deposition sequence, in particular during the relative movement of the material deposition track relative to the manufacturing support in the forward direction, each material deposition nozzle is configured to deposit molten material in a given material line at a certain thickness. All the material deposition nozzles deposit material in the first layer corresponding to the width of the three-dimensional object to be manufactured.

[0072] After each material deposition sequence, i.e., after each material layer is fabricated, the lateral position of the fabrication support is reset and a relative movement of the material deposition track relative to the fabrication support along the vertical axis is generated so that the track moves away from the support in the vertical direction. Then, each of the material deposition nozzles is actuated to deposit molten material in accordance with the same given lateral material lines to form a second layer. These operations are repeated until the desired thickness of the object to be fabricated is obtained. A closing device for certain nozzles can also be set in a closed position to produce a specific geometry. Similarly, it is also conceivable to deposit material on the already deposited material layers in the opposite direction without resetting the position of the fabrication support.

[0073] Similarly, it can be provided that the material deposition track can be translated relative to the fabrication support along the vertical axis, or as a variant, the fabrication support can be translated relative to the material deposition track along the vertical axis.

[0074] Generally, the number of rows depends on the width of the three-dimensional object to be fabricated.

[0075] According to one embodiment, the width of the material deposition track is less than the width of the three-dimensional object to be fabricated.

[0076] In this case, in each material deposition sequence, particularly during the relative movement of the material deposition track relative to the fabrication support in the forward direction, each material deposition nozzle is configured to deposit material in a given thickness along a given material line, and after each thickness is fabricated along a given lateral material line, the material deposition track is configured to axially translate the width of the track relative to the fabrication support along the longitudinal axis, the number of translations being the same as the number of times required to fabricate the first layer including all the material lines. These operations are repeated until all the superimposed layers of the desired thickness for forming the object to be fabricated are obtained.

[0077] According to another variant, it can be provided that the width of the material deposition track is equal to or even greater than the width of the three-dimensional object to be fabricated, but the density of the material deposition nozzles can be reduced to reduce costs. In this case, after each material deposition sequence, i.e., after each nozzle has deposited material along a given line, the material deposition track is configured to axially translate the width offset of the material deposition nozzles relative to the fabrication support along the longitudinal axis, the number of translations being the same as the number of times required to produce the first layer including all the material lines. Similarly, each material deposition nozzle is configured to deposit material on multiple material lines in multiple material deposition sequences.

[0078] According to one embodiment, the material deposition nozzles are arranged in the same plane containing the longitudinal axis, and the nozzles are offset relative to each other in the vertical direction.

[0079] In this case, at least one material deposition nozzle may be configured to deposit material on all circumferential lines of the entire material layer in a plurality of material deposition sequences, and the material deposition track is configured to axially translate the material line only along the longitudinal axis relative to the manufacturing support by a distance after each material deposition sequence.

[0080] At this time, the number of material deposition nozzles depends on the number of layers to be printed.

[0081] In this case, at least one material deposition nozzle of the material deposition track is configured to deposit material on the material line of the first material layer. After each material deposition sequence, the material deposition track is configured to axially translate the material line only along the longitudinal axis relative to the manufacturing support by a distance. These operations are repeated until at least one material deposition nozzle deposits material on the entire first material layer including all material lines.

[0082] Next, adjacent nozzles are configured to deposit material on the material lines of the second material layer superimposed on the first layer. These operations are repeated until the desired thickness of the object to be manufactured is obtained.

[0083] For example, the nozzles are actuated simultaneously to deposit material in accordance with the material lines located on the lower material lines, and then the material deposition track is configured to axially translate the circumferential material line along the longitudinal axis relative to the manufacturing support by a distance after each material deposition sequence, so that the material deposition nozzle creates adjacent lines, and so on until the desired geometry of the three-dimensional object is obtained.

[0084] According to another embodiment, an apparatus for additive manufacturing of an object includes two material deposition tracks respectively associated with dedicated actuation systems, and the tracks are capable of translating in two opposite directions in the longitudinal direction. The two material deposition tracks are configured to co-deposit a single material layer.

[0085] According to one embodiment, the apparatus includes a member for driving the manufacturing support, and the member is capable of driving the manufacturing support in the forward direction.

[0086] According to one embodiment, the actuation system is configured to translate the material deposition track relative to the manufacturing support in the vertical direction and / or the longitudinal direction.

[0087] According to a second aspect, the present invention relates to a method for additive manufacturing of all or part of a three-dimensional object on a manufacturing support using a manufacturing apparatus, the manufacturing apparatus including at least one material deposition track disposed above the manufacturing support, extending along an extension axis (here the longitudinal axis), and including a plurality of additive deposition nozzles, each additive deposition nozzle being provided with at least one dispensing hole, wherein:

[0088] - In a material deposition sequence, each of the material deposition nozzles deposits extruded material onto a build support.

[0089] - A closing device associated with one of the material deposition nozzles is controlled independently of the others to move between a closed position and a plurality of open positions of the dispensing orifice of each nozzle according to the geometry of the three-dimensional object to be manufactured.

[0090] - After each material deposition sequence, the material deposition track and the build support are translated relative to each other in at least a vertical direction and / or a longitudinal direction.

[0091] According to one embodiment, in each material deposition sequence, the build support is translated along a transverse axis relative to the material deposition track between an initial position and a final position and returns to its initial position at the end of each material deposition sequence. As a variant, it is also conceivable that the build support does not return to the initial position to deposit material on the next layer but starts at the final position of the previous layer and creates the layer in the opposite direction. This makes it possible to save time as there is no time required to return to the initial position.

[0092] In each material deposition sequence, each material deposition nozzle deposits material over at least the thickness of one given material line. All the material deposition nozzles deposit material in a first layer corresponding to the width of the three-dimensional object to be manufactured. And after each material deposition sequence, the material deposition track is translated relative to the build support along a vertical axis and each of the material deposition nozzles deposits material according to the same given material line to form a second layer superimposed on the first layer. These operations are repeated until the desired thickness of the three-dimensional object is obtained.

[0093] Thus, each material deposition sequence produces an entire layer.

[0094] The material deposition track may be translated relative to the build support along a vertical axis. As a variant, the material deposition track may be fixed relative to the support of the manufacturing device and the build support is translated relative to the material deposition track along a vertical axis.

[0095] According to one embodiment, the width of the material deposition track is less than the width of the tread to be manufactured. In each material deposition sequence, each material deposition nozzle deposits material over a given thickness according to a given material line. After each material deposition sequence, the material deposition track is axially translated along the longitudinal axis by the width of the track relative to the tire. These operations are repeated until a first material layer including all the material lines is obtained.

[0096] The material deposition track can be translated along the longitudinal axis relative to the manufacturing support. As a variant, the material deposition track can be fixed relative to the support of the manufacturing device, and the manufacturing support is translated along the longitudinal axis relative to the material deposition track.

[0097] Thus, in a plurality of material deposition sequences, each material deposition nozzle deposits material on a plurality of material lines. Next, the manufacturing support is translated along the transverse axis relative to the material deposition track in its initial position, and the material deposition track is translated relative to the manufacturing support in the vertical direction to create a second layer, and so on until the desired thickness of the three-dimensional object is obtained.

[0098] According to another variant, the width of the material deposition track can be set to be equal to or greater than the width of the three-dimensional object to be manufactured, but the density of the material deposition nozzles can be reduced to reduce costs. In this case, after each material deposition sequence, the material deposition track is axially translated along the longitudinal axis relative to the manufacturing support by the width of the material deposition nozzle, and the number of translations is the same as the number required to produce the first layer including all the material lines. Similarly, in a plurality of material deposition sequences, each material deposition nozzle deposits material on a plurality of material lines.

[0099] According to another embodiment where the width of the material deposition track is equal to the width of the three-dimensional object to be manufactured, in each material deposition sequence, at least one material deposition nozzle deposits material on the circumferential material lines of the entire material layer. After each material deposition sequence, the manufacturing support is translated along the transverse axis relative to the material deposition track in its initial position, and the material deposition track is only axially translated along the longitudinal axis relative to the manufacturing support by the distance of the material line. These operations are repeated until at least one material deposition nozzle deposits material on the entire material layer including all the material lines.

[0100] At this time, the number of material deposition nozzles depends on the number of layers to be printed.

[0101] In this case, in the material deposition sequence, the nozzles are actuated simultaneously to deposit material according to the material lines located on the lower material lines, and then the material deposition track is axially translated along the longitudinal axis relative to the manufacturing support by the distance of the material line after each material deposition sequence, so that the material deposition nozzles deposit material along adjacent material lines, and so on until the desired three-dimensional object is obtained. Description of the Drawings

[0102] Other objects, features and advantages of the present invention will become apparent by reading the description given by way of non-limiting examples with reference to the following accompanying drawings, in which:

[0103] Figure 1Shows very schematically a device for additive manufacturing of a tread according to the invention, configured to manufacture a tread on a tire of a wheel according to a first embodiment;

[0104] Figure 2 Shows another example of a wheel on which the additive manufacturing device of Figure 1 can be used;

[0105] Figure 3 Shows Figure 1 details of the material deposition nozzle of the additive manufacturing device of

[0106] Figure 4 , Figure 5 Schematically shows details of the additive manufacturing device of the tread of Figure 1 according to a first embodiment of the invention;

[0107] Figure 6 , Figure 7 Schematically shows details of the additive manufacturing device of the tread of Figure 1 according to a second embodiment of the invention;

[0108] Figure 8 , Figure 9 Schematically shows details of the additive manufacturing device of the tread of Figure 1 according to a third embodiment of the invention;

[0109] Figure 10 , Figure 11 Schematically shows details of the additive manufacturing device of the tread of Figure 1 according to a fourth embodiment of the invention;

[0110] Figure 12 Schematically shows details of the additive manufacturing device of the tread of Figure 1 according to a fifth embodiment of the invention; and

[0111] Figure 13 Shows another example of a support on which the additive manufacturing device of Figure 1 can be used. DETAILED DESCRIPTION

[0112] The following description refers to an orthogonal coordinate system X, Y, Z defined relative to the additive manufacturing device 10, which consists of the following axes:

[0113] - A longitudinal axis X, which is horizontal in Figure 1 and extends from back to front;

[0114] - A transverse axis Y, which is in Figure 1is horizontal, perpendicular to the longitudinal axis X, and extends from left to right; and

[0115] - a vertical axis Z, which is Figure 1 perpendicular to the longitudinal axis X and the transverse axis Y in

[0116] As Figure 1 shown, the mounting assembly 1 or wheel includes a rim 2 and a tire 4 or pneumatic tire mounted on the rim 2, the rim 2 including a fastening hub 3. The tire 4 includes a tread bearing surface 5, a tread 6, and two sidewalls 7 on both sides of the tread bearing surface 5, Figure 1 only one of the sidewalls can be seen in

[0117] The rim 2 is preferably a final rim intended to be mounted on a motor vehicle.

[0118] The fastening hub 3 forms a fastening interface between the wheel 1 and the vehicle.

[0119] Here, the fastening hub 3 defines a hollow fastening cylinder that can accommodate a wheel axle (not shown).

[0120] Here, the tire 4 withstands the internal pressure through an air chamber (not shown) inflated to a recommended nominal inflation pressure or a lower pressure.

[0121] As a variant form, the mounting assembly 1 can be a tubeless wheel, which includes an insert (not shown) made of multilayer foamed plastic to replace the air chamber.

[0122] The mounting assembly 1 can also be a so-called "non-pneumatic" tire.

[0123] The tread 6 includes two side surfaces (not numbered), an inner surface (not shown) rigidly connected to the tread bearing surface 5, and a tread surface 6a opposite the inner surface and intended to contact the road S when the wheel 1 is in motion.

[0124] The tread 6 includes a plurality of incisions or tread patterns extending on at least one of its side surfaces.

[0125] Here, the rim 2 forms a radial support structure for the tire 4.

[0126] As Figure 1 shown, the device 10 for additive manufacturing of the tread 6 is configured to deposit the extruded material forming the tread 6 on the circumferential bearing surface 5 of the tire 4 of the wheel 1.

[0127] Generally, the device 10 for additive manufacturing of the tread 6 is configured to deposit the extruded material forming the tread 6 on the tire 4. It is possible to manufacture the tread 6 on the tire 4 not mounted on the wheel.

[0128] It is also possible to provide for a new tread 6 to be refilled on a worn tread surface. In this case, the support surface corresponds to the worn tread surface.

[0129] "Tire" means all types of elastic tires with a toroidal shape, with or without internal pressure.

[0130] The "tread" of a tire means a quantity of rubber material delimited by a side surface and two main surfaces, one of the main surfaces being called the tread surface and intended to come into contact with the road when the tire is in motion. The tread includes a plurality of incisions or tread patterns extending on at least one side surface.

[0131] The "sidewall" of a tire means the part of the side surface of the tire that is located between the tread of the tire and the support structure of the wheel. In the case of a tire of a conventional wheel, the sidewall extends from the end of the incision of the tread to the bead of the tire.

[0132] The additive manufacturing device 10 includes a fixed support 12 and one or more material deposition tracks 20, 30 that are mounted translatably relative to the fixed support 12.

[0133] By way of non-limiting example, the fixed support 12 includes a base 14 fastened to the ground S and a vertical arm 16 for fastening the material deposition tracks 20, 30.

[0134] The material deposition tracks 20, 30 are arranged above the wheel 1, in particular above the tread of the tire 4.

[0135] The tracks 20, 30 extend along an extension axis (here the longitudinal axis X).

[0136] The additive manufacturing device 10 includes an extruder 18 connected to the material deposition tracks 20, 30, which is configured to produce a line of molten material from, for example, particles of material (preferably plastic, such as a thermoplastic elastomer (TPE)). Thus, thermal extrusion of the particles of material is carried out.

[0137] The line of molten material is continuous.

[0138] Here, the extruder 18 is located centrally and supplies the tracks 20, 30 with a line of molten material from the particles. In other words, the central extruder is associated with all the material deposition nozzles. As a variant, for a single extruder, positions other than the central position can be envisaged.

[0139] As a variant, the central extruder 18 supplies the tracks 20, 30 with a line of molten material from one or more filaments or even strips.

[0140] As a variant, at least one extruder associated with at least one material deposition nozzle can be provided.

[0141] For example, multiple extruders can be provided, each extruder being associated with at least two material deposition nozzles.

[0142] The tread 6 is manufactured by depositing the extruded material layer by layer on the bearing surface 5 of the tire 4. The extruded material melts on the previously deposited material layer and solidifies as the temperature drops.

[0143] For this purpose, the material deposition tracks 20, 30 include multiple nozzles 21, 22, 23, 24 and 31, 32, 33, 34, 35, 36, 37, 38, and these nozzles are described in detail with reference to Figures 3 to 12 Each of the nozzles is configured to deposit the molten material on the bearing surface 5 of the tire 4 that can rotate around the horizontal rotation axis X-X.

[0144] Performing additive manufacturing on a continuously rotating support (here, the bearing surface 5 of the tire 4, or more generally, the tire 4) enables the complete manufacture or reconstruction of the tread 6 over the entire circumference of the tread 6.

[0145] "Continuous rotation" means rotating in a single rotation direction without interruption at a constant speed.

[0146] "Discontinuous rotation" means rotating in a single rotation direction at a variable speed during the deposition of the material.

[0147] For this purpose, the additive manufacturing device 10 includes a member 15 for rotating the tire 4 around the rotation axis X-X.

[0148] As Figure 1 shown, the rotating member 15 is in the form of a rotating drum or cylinder, which cooperates with the wheel hub 3 and is configured to rotate the tire 4 through the wheel hub 3.

[0149] As a variant form, it can be provided that the rotating member includes rollers arranged under the wheel to rotate the wheel by friction when the tire is mounted on the wheel.

[0150] According to another variant form, it can be provided that the rotating member is configured to act directly on the sidewall 7 of the tire 4.

[0151] These variant forms are beneficial in cases where it is necessary to manufacture the tread 2 without removing the wheel 1 from the vehicle.

[0152] The additive manufacturing device 10 further includes an actuation system (not shown), the actuation system being configured to move the material deposition tracks 20, 30 relative to the wheel 1 in the vertical direction Z and / or the longitudinal direction X parallel to the rotation axis X-X across the width of the wheel 1. Thus, all the nozzles move synchronously while the material deposition tracks 20, 30 move.

[0153] The apparatus 10 for additive manufacturing of a tread can also be used for manufacturing or refilling a tread 6' on a support surface 5' of a tire 4' of a one-piece wheel 1' as shown in Figure 2 .

[0154] Here, the one-piece wheel 1' includes a radial support structure 2', around which a solid tire 4' is fastened. The solid tire 4' includes a support 7' located radially outside the support structure 2'. The support 7' extends over the entire circumference of the support structure 2' and bears the tread 6'. Here, the tread 6' is structurally integrated into the support 7' via a tread support surface 5', which forms the outer peripheral contour of the radial support structure 2'.

[0155] The solid tire 4' does not withstand internal pressure.

[0156] As shown in Figure 2 , the radial support structure 2' includes a fastening hub 3' for fastening the wheel 1' to a vehicle.

[0157] Here, the fastening hub 3' defines a hollow fastening cylinder that can accommodate an axle (not shown).

[0158] The radial support structure 2' is made, for example, of glass fiber-reinforced plastic.

[0159] Here, the support structure 2' includes a plurality of spokes or ribs 8' connecting the hub 3' to the support 7'.

[0160] As shown in Figure 2 , the support structure 2' includes five spokes 8'. As a variant, a number of spokes 8' between three and nine can be envisaged.

[0161] An opening or window 9' is defined between two adjacent spokes 8'. Here, the openings 9' are evenly distributed in the circumferential direction.

[0162] Here, the opening 9' has an oval contour. As a variant, other shapes of the contour of the opening 9' can be envisaged.

[0163] Here, the support structure 2' and the support 7' include a three-dimensional beam or grid network or structure.

[0164] As a variant, it can be provided that the radial support structure 2' includes a plurality of vanes arranged radially to support the tire 4' (in particular the support 7').

[0165] As shown in Figure 3As shown, each of the material deposition nozzles or spray heads 21, 22, 23, 24 and 31, 32, 33, 34, 35, 36, 37, 38 includes a chamber 25 for receiving molten material from the central extruder 18 and a distribution hole 26 in communication with the chamber 25.

[0166] The distribution hole 26 has a size between 0.6 mm and 1.5 mm, preferably between 0.6 mm and 0.8 mm (for producing a 1 mm wide material deposit), and preferably between 1 mm and 1.5 mm (for producing a 2 mm wide material deposit).

[0167] The distribution hole 26 of each nozzle has a rectangular or circular cross-section. The rectangular cross-section enables improvement in the level of detail of the tread pattern and the quality of the interruption.

[0168] Each of the material deposition nozzles 21 to 24 and 31 to 38 includes a closing device 28, which includes a closing means 28a and an actuator 28b. The closing means 28a can be moved between a closed position and an open position of the distribution hole 26, and the actuator 28b is used to control the movement of the closing means 28a between the closed position and the open position. The closing means 28a can be controlled independently of each other.

[0169] Thus, each nozzle includes its own closing device 28 configured to interrupt the flow of molten material through the distribution hole 26 of the corresponding nozzle.

[0170] Each of the nozzles can be interrupted independently and responsive to produce any tread pattern or geometry on the wheel 1 in a short time (preferably less than 20 minutes, more preferably less than 15 minutes).

[0171] This filling duration corresponds to a material deposition rate between 10 kg / hr and 20 kg / hr, preferably equal to 12 kg / hr.

[0172] The closing frequency is between 10 Hz and 30 Hz, for example equal to 20 Hz.

[0173] In Figure 3 In the illustrated embodiment, the closing means 28a is in the form of a needle actuated by the actuator 28b.

[0174] The actuator 28b includes, for example, a piezoelectric device (not shown) for closing or opening the distribution hole 26 of the corresponding nozzle.

[0175] The needle-type closing means 28a enables a sharp interruption of the flow of molten material (without burrs) and an unobstructed resumption of the flow.

[0176] As a variant form, any other closing device associated with each nozzle can be provided, such as a valve.

[0177] According to a non - limiting embodiment, the additive manufacturing device 10 may include a volumetric metering device (not shown) disposed downstream of the central extruder and upstream of the material deposition tracks 20, 30.

[0178] For example, the volumetric metering device is a gear pump. The volumetric metering device is configured to deposit a calibrated amount of molten material onto the bearing surfaces 5, 5' of the tires 4, 4'. Thus, a material line of constant width can be obtained, which is different from the way of depositing material in the form of a series of droplets known in the prior art.

[0179] The terms "downstream" and "upstream" are defined with respect to the flow direction of the material.

[0180] Reference Figure 4 and Figure 5 shows an embodiment of the material deposition track 20.

[0181] In this embodiment, the material deposition track 20 is configured to deposit the extruded material in a circumferential material line Li, and the extruded material forms a tread 6, 6' on the tires 4, 4' (especially on their circumferential bearing surfaces 5, 5').

[0182] Depositing the material in a "circumferential material line" Li means depositing the material on the circular path of the tires 4, 4', where i ranges from 1 to x and x is the total number of material lines.

[0183] A "material layer" Cj means all the circumferential or transverse material lines Li arranged side by side over the entire width of the tread 6, 6' to be manufactured, where j ranges from 1 to y and y is the total number of material layers for forming the desired thickness of the tread 6, 6'.

[0184] The material layer C corresponds to the thickness of the deposited molten material.

[0185] A "row" R means an arrangement along a longitudinal axis X parallel to the rotation axis X - X of the tires 4, 4' and perpendicular to the vertical direction Z. The row R is provided over the width of the tires 4, 4' (especially their bearing surfaces 5, 5').

[0186] As Figure 4 and Figure 5 shown, the material deposition track 20 includes a plurality of material deposition nozzles 21, 22, 23, 24, here the number is twenty - four, and each material deposition nozzle is intended to build all the thicknesses or layers of at least one circumferential material line Li.

[0187] "Thickness" means the material layer deposited on the material line.

[0188] As shown in the figure, here, the number of material deposition nozzles is twenty-four, and the number of material lines Li is also equal to twenty-four. Therefore, i ranges from one to twenty-four.

[0189] As a variant form, different numbers of material deposition nozzles can be set.

[0190] As shown in the figure, here, the number of material layers Cj is six. Therefore, j ranges from one to six.

[0191] As a variant form, different numbers of material layers Cj can be set.

[0192] As shown in the figure, the width of the material deposition track 20 is at least equal to the width of the treads 6, 6' to be manufactured.

[0193] When the wheels 4, 4' rotate continuously below the material deposition track 20, each of the material deposition nozzles is actuated to deposit material on a given circumferential material line Li. The first nozzle 24 deposits material on the first line L1, and the second nozzle 23 adjacent to the first nozzle 24 deposits material on the second line L2 adjacent to the first line L1 at the same time, and so on, until the entire layer including all adjacent circumferential lines Li is produced.

[0194] Therefore, the entire layer is produced each time the tire 4, 4' makes a complete rotation. After each complete rotation of the tire, the material deposition track 20 is translated along the vertical axis Z relative to the tire 4, 4', and each of the material deposition nozzles 21, 22, 23, 24 is actuated to deposit molten material according to the same given circumferential material line Li, thereby forming a second layer. These operations are repeated until the desired thickness of the treads 6, 6' is obtained.

[0195] In Figure 4 and Figure 5 the illustrated embodiment, a single material deposition nozzle 21, 22, 23, 24 is configured to build all the thicknesses of a given circumferential material line Li.

[0196] Here, the material deposition nozzles 21, 22, 23, 24 are arranged in rows R1, R2, R3, R4 offset along the transverse axis Y on the material deposition track 20.

[0197] In fact, a distance of 4 mm may need to be set between the respective material deposition nozzles.

[0198] As shown in the figure, the material deposition track includes four rows R1, R2, R3, R4, and each row includes six material deposition nozzles 21, 22, 23, 24. As a variant form, different numbers of rows can be set, for example, greater than or equal to two rows. Different numbers of nozzles can also be set for each row R.

[0199] The number of rows R depends on the width of the treads 6, 6' to be manufactured.

[0200] As a variant form, it is also possible to arrange the material deposition nozzles 21, 22, 23, 24 in a single row R1 along the longitudinal direction X on the material deposition track 20.

[0201] As a variant form, it is possible to set the material deposition track 20 to have a width different from that of the treads 6, 6' to be manufactured.

[0202] For example, it is possible to set the width of the material deposition track 20 to be smaller than the width of the treads 6, 6' to be manufactured. In this case, for each complete rotation of the tire 4, 4', each material deposition nozzle 21 to 24 deposits material at a certain thickness according to a given circumferential material line Li, and after each complete rotation of the tire 4, 4', the material deposition track 20 is axially translated along the longitudinal axis X relative to the tire 4, 4' by the width of the track 20, and the number of translations is the same as the number of times required to manufacture the first layer including all the material lines Li. After manufacturing each layer including all the material lines Li, the material deposition track 20 is translated relative to the tire 4, 4' along the vertical axis Z, and the operation of manufacturing the layer is repeated.

[0203] These operations are repeated until all the superimposed layers with the required thickness for forming the treads 6, 6' are obtained.

[0204] For example, for a support surface 5, 5' with a width of 225 mm and a material deposition track 20 with a width of 80 mm, the tire 4, 4' rotates three complete circles, and for each complete rotation, the material deposition track 20 is offset by 80 mm along the longitudinal axis X.

[0205] Therefore, each material deposition nozzle 21, 22, 23, 24 deposits material on a plurality of given circumferential material lines Li during multiple complete rotations of the tire 4, 4'.

[0206] According to another variant form, it is possible to set the width of the material deposition track 20 to be equal to or greater than the width of the treads 5, 5' to be manufactured, or more generally, equal to or greater than the width of the support surface 5, 5', but reduce the density of the material deposition nozzles to reduce costs. In this case, after each complete rotation of the tire 4, 4', the material deposition track 20 is axially translated along the longitudinal axis X relative to the tire 4, 4' by the width of the material deposition nozzles 21, 22, 23, 24, and the number of translations is the same as the number of times required to produce the first layer C1 including all the material lines Li. After manufacturing each layer including all the material lines Li, the material deposition track 20 is translated relative to the tire 4, 4' along the vertical axis Z, and the operation of manufacturing the layer is repeated.

[0207] Repeat these operations until all the superimposed layers with the desired thickness for forming the treads 6, 6' are obtained.

[0208] Similarly, each material deposition nozzle deposits material on multiple material lines during multiple full rotations of the tires 4, 4'.

[0209] However, this variant form increases the total manufacturing time of the tread.

[0210] As shown in the figure, the additive manufacturing device 10 includes a single material deposition track 20 surrounding the tires 4, 4'.

[0211] As a variant form, it can be arranged that the additive manufacturing device 10 includes at least two material deposition tracks 20, which are respectively associated with dedicated actuation systems and are circumferentially arranged around the tire in two given orientations.

[0212] For example, a first track located in a first given orientation and a second track arranged at 180° to the first track can be provided. As a variant form, it can be arranged that the second track is arranged at an angle between 10° and 350°, preferably between 30° and 320°, relative to the first track.

[0213] As a variant form, different numbers of tracks, such as greater than or equal to three tracks, can be provided, which are respectively associated with dedicated actuation systems and are circumferentially arranged around the tire in three given orientations.

[0214] Reference Figure 6 and Figure 7 shows another embodiment of the material deposition track 30.

[0215] In this embodiment, the material deposition track 30 is configured to deposit the extruded material for forming the treads 6, 6' on the tires 4, 4' (especially on their circumferential support surfaces 5, 5').

[0216] In this embodiment, the widths of the material deposition tracks 30, 30a, 30b are equal to the widths of the treads 6, 6' to be manufactured, and each material deposition nozzle 31 to 38 is configured to build the entire material layer Cj.

[0217] During each full rotation of the tire, one of the material deposition nozzles of the material deposition track 30 deposits material on the circumferential material line Li of the material layer Cj. After each full rotation of the tires 4, 4', the material deposition track 30 only axially translates the material line Li relative to the tires 4, 4' by a distance along the longitudinal axis X. Repeat these operations until each material deposition nozzle 31 to 38 deposits material on the entire material layer Cj including all the material lines Li.

[0218] In other words, when the tires 4, 4' rotate a complete circle, the nozzles 31 to 38 are actuated continuously to create a given circumferential material line Li. The first nozzle 31 deposits material on the first line L8 with a first thickness, then the material deposition track 30 axially moves the width of the material line Li along the longitudinal axis X relative to the tires 4, 4', and the first nozzle 31 deposits material on the second line L7. The second nozzle 32 adjacent to the first nozzle 31 deposits material on the first line L8 with a second thickness of a layer superimposed on the first line formed by the first nozzle, and so on, until each material deposition nozzle creates a given layer Cj until the desired tread pattern of the treads 6, 6' is obtained.

[0219] Therefore, the first material deposition nozzle 31 creates the first layer C1, the second nozzle 32 creates the second layer C2, the third nozzle 33 creates the third layer C3, and so on, until the desired total thickness of the treads 6, 6' is obtained. Thus, each of the material deposition nozzles 31 to 38 is configured to build the entire material layer Cj.

[0220] Therefore, the layer Cj is built lagging one circle behind the previous layer.

[0221] This arrangement can use fewer material deposition nozzles compared to depositing material with nozzles configured to deposit material along the material line Li.

[0222] In this embodiment, the material deposition track 30 does not translate along the vertical axis Z.

[0223] At this time, the number of the material deposition nozzles 31 to 38 depends on the number of material layers to be built.

[0224] Here, the material deposition nozzles 31 to 38 are arranged in rows R1, R2, R3, R4 offset along the vertical axis Z.

[0225] In fact, a distance of 4 mm may need to be set between the respective material deposition nozzles.

[0226] As shown in the figure, the material deposition track includes eight material deposition nozzles 31 to 38. As a variant, a different number of material deposition nozzles can be set, for example, greater than or equal to six.

[0227] As shown in the figure, the number of the material lines Li is equal to eight. As a variant, a different number of material lines Li can be set. The number of the material lines depends on the width of the treads 6, 6' to be manufactured.

[0228] As shown in the figure, the number of the material layers Cj is equal to eight. As a variant, a different number of material layers Cj can be set. The number of the material layers Cj depends on the total thickness of the treads 6, 6' to be manufactured.

[0229] For example, if the thickness of layer Cj is 0.8 mm and the total thickness of the tread to be manufactured is 8 mm, ten material deposition nozzles can be used.

[0230] However, the rotational speed of the tires 4, 4' and the closing frequency of the nozzles are higher than those of the nozzles for depositing material along the material line Li as described in detail in the reference Figure 3 and Figure 4 configuration.

[0231] In Figure 6 and Figure 7 the illustrated embodiment, the material deposition nozzles 31 to 38 deposit material on the same material line Li with an offset along the longitudinal axis X.

[0232] As shown, the nozzles 31 to 38 are also offset along the vertical axis Z, so that it is no longer necessary to move the material deposition track in the vertical direction relative to the tires 4, 4'.

[0233] Figure 8 and Figure 9 (wherein the same elements have the same reference numerals) the illustrated embodiment differs from the Figure 6 and Figure 7 illustrated embodiment only in that layer Cj is constructed two turns behind the previous layer.

[0234] As Figure 8 and Figure 9 shown, the material deposition track 30 includes eight material deposition nozzles 31 to 38. As a variant, a different number of material deposition nozzles can be provided, for example, greater than or equal to six.

[0235] As shown, the number of material lines Li is equal to fifteen. As a variant, a different number of material lines Li can be provided. The number of material lines depends on the width of the treads 6, 6' to be manufactured.

[0236] As shown, the number of material layers Cj is equal to eight. As a variant, a different number of material layers Cj can be provided. The number of material layers Cj depends on the total thickness of the treads 6, 6' to be manufactured.

[0237] Figure 10 and Figure 11 (wherein the same elements have the same reference numerals) the illustrated embodiment differs from the Figure 8 and Figure 9 illustrated embodiment only in that two material deposition nozzles 31a, 31b to 38a, 38b are configured to construct an entire material layer including all adjacent circumferential lines Li in terms of thickness. Layer Cj is constructed two turns behind the previous layer.

[0238] As Figure 10 andFigure 11 As shown, the material deposition track 30 includes sixteen material deposition nozzles 31a, 31b to 38a, 38b. As a variant, a different number of material deposition nozzles can be provided, for example, greater than or equal to eight.

[0239] As shown, the number of material lines is equal to twenty-three. As a variant, a different number of material lines can be provided. The number of material lines depends on the width of the treads 6, 6' to be manufactured.

[0240] As shown, the number of material layers Cj is equal to eight. As a variant, a different number of material layers Cj can be provided. The number of material layers Cj depends on the total thickness of the treads 6, 6' to be manufactured.

[0241] Figure 12 (wherein the same elements have the same reference numerals) the embodiment shown is different from Figure 8 and Figure 9 the embodiment shown only in that the additive manufacturing device 10 includes two material deposition tracks 30a, 30b.

[0242] The additive manufacturing device 10 includes a first actuation system (not shown) configured to translate the first material deposition track 30a relative to the tire 4, 4' in a first direction along the longitudinal direction X parallel to the rotational axis X-X across the width of the tire 4, 4'.

[0243] The additive manufacturing device 10 includes a second actuation system (not shown) configured to translate the second material deposition track 30b relative to the wheel 1, 1' in a second direction along the longitudinal direction X across the width of the tire 4, 4'.

[0244] The first direction is opposite to the second direction.

[0245] Thus, the two material deposition tracks 30a, 30b are configured to move in opposite directions relative to the tire 4, 4' along the longitudinal axis X starting from the middle of the tire 4, 4'. The two material deposition tracks 30a, 30b are configured to deposit material together on a single layer Cj.

[0246] Each track 30a, 30b corresponds to one of the tracks described with reference to Figures 6 to 11 description.

[0247] As Figure 12 shown, each material deposition track 30a, 30b includes eight material deposition nozzles (un-numbered marks). As a variant, a different number of material deposition nozzles can be provided, for example, greater than or equal to six.

[0248] As shown in the figure, the number of material lines Li is equal to sixteen. As a variant form, a different number of material lines can be set. The number of material lines depends on the width of the treads 6, 6' to be manufactured.

[0249] As shown in the figure, the number of material layers Cj is equal to four. As a variant form, a different number of material layers Cj can be set. The number of material layers Cj depends on the total thickness of the treads 6, 6' to be manufactured.

[0250] In Figures 1 to 12 the embodiment shown, the additive manufacturing device 10 has been described for manufacturing the treads 6, 6' of the tires 4, 4'.

[0251] However, the present invention is not limited to manufacturing the treads of tires. The additive manufacturing device 10 is actually configured to manufacture any type of three-dimensional object having a cylindrical or non-cylindrical shape (such as a parallelepiped).

[0252] Reference can be made in this regard to Figure 13 which shows a manufacturing support 104 for a three-dimensional object 106 (here a cuboid).

[0253] Here, the manufacturing support 104 is in the form of a platform extending in a plane XY including a longitudinal axis X and a transverse axis Y. The platform 104 includes an outer support surface (not numbered) for receiving successive extruded material layers Cj, said successive extruded material layers Cj coming from the tracks 20, 30 of the additive manufacturing device 10 and forming the manufactured three-dimensional object 106.

[0254] As a variant form, a flat shape other than a parallelepiped can be envisaged for the platform 104.

[0255] The object 106 to be manufactured can be manufactured using one or more material deposition tracks 20 as described in detail with reference to Figure 4 and Figure 5 or using one or more material deposition tracks 30, 30a, 30b as described in detail with reference to Figures 6 to 11 .

[0256] Generally, the manufacturing support 104 of the additive manufacturing device 10 and one or more tracks 20, 30, 30a, 30b are moved relative to each other at least in the longitudinal direction X and / or the vertical direction Z.

[0257] The additive manufacturing device 10 includes a member 15 for driving the manufacturing support 104 at least translationally, said member 15 being capable of translating the manufacturing support 104 at least in the forward direction (here along the transverse axis Y).

[0258] Typically, the advancing direction of manufacturing the support member 104 is perpendicular to the extension axis of the tracks 20, 30, which is the longitudinal axis X here.

[0259] Similar to the Figures 4 to 11 illustrated embodiment, the additive manufacturing apparatus 10 further includes an actuation system (not shown), which is configured to generate relative translation of the material deposition tracks 20, 30 relative to the manufacturing support member 104 in the vertical direction Z and / or the longitudinal direction X. Thus, when the material deposition tracks 20, 30 move, all the material deposition nozzles move simultaneously while the material deposition tracks 20, 30 move.

[0260] Here, the longitudinal direction is parallel to the longitudinal axis X of the tracks 20, 30, or may coincide with the longitudinal axis X.

[0261] The "width" of the object 106 to be manufactured means the dimension along the longitudinal axis X. The width may also be the dimension along the transverse axis Y. Typically, the width of the object 106 to be manufactured corresponds to the extension (which is the longitudinal axis X here) dimension of the tracks 20, 30. If the object 106 is manufactured by a plurality of material deposition nozzles 21, 22, 23, 24 of the material deposition track 20 Figure 4 and Figure 5 described in detail, each of the nozzles 21 to 24 is intended to build all the thicknesses or layers of at least one given transverse material line Li.

[0262] According to one embodiment, the width of the material deposition track 20 is equal to the width of the object 106 to be manufactured.

[0263] Each of the material deposition nozzles is actuated to deposit material on a given transverse material line Li. The first nozzle 24 deposits material on the first line L1, and the second nozzle 23 adjacent to the first nozzle 24 deposits material on the second line L2 adjacent to the first line L1 at the same time, and so on, until the entire layer including all adjacent transverse lines Li is produced.

[0264] After each material layer Cj (corresponding to the material deposition sequence) is manufactured, the material deposition track 20 is translated relative to the manufacturing support member 104 along the vertical axis Z, and each of the material deposition nozzles 21, 22, 23, 24 is actuated to deposit molten material according to the same given transverse material line Li, thereby forming the second layer. These operations are repeated until the required thickness of the object 106 to be manufactured is obtained.

[0265] The material deposition track 20 is capable of translating along the vertical axis Z relative to the manufacturing support 104. As a variant, the material deposition track 20 can be fixed relative to the support 12 of the manufacturing apparatus 10, and the manufacturing support 140 is capable of translating along the vertical axis Z relative to the material deposition track 120.

[0266] Advantageously, the manufacturing support 104 and the track 20 of the additive manufacturing apparatus 10 are moved relative to each other at least in the forward direction (here the lateral direction Y).

[0267] Similarly, it can be provided that the material deposition track 20 is capable of translating along the lateral axis Y relative to the manufacturing support 104, or as a variant, the manufacturing support 104 is capable of translating along the lateral axis Y relative to the material deposition track 20.

[0268] During the relative movement of the material deposition track 20 relative to the manufacturing support 104 in the lateral direction Y, each of the material deposition nozzles is actuated to deposit material on a given lateral material line Li. The first nozzle 24 deposits material on the first line L1, and the second nozzle 23 adjacent to the first nozzle 24 simultaneously deposits material on the second line L2 adjacent to the first line L1, and so on, until an entire layer including all adjacent lateral lines Li is produced.

[0269] After each material layer Cj (corresponding to the material deposition sequence) is manufactured, the lateral position of the manufacturing support 104 is reset, and a relative movement of the material deposition track 20 relative to the manufacturing support 104 along the vertical axis Z is generated so that the track 20 moves away from the support 104 in the vertical direction. Then, each of the material deposition nozzles 21, 22, 23, 24 is actuated to deposit molten material in accordance with the same given lateral material line Li, thereby forming a second layer. These operations are repeated until the desired thickness of the object 106 to be manufactured is obtained.

[0270] Similarly, it can be provided that the material deposition track 20 is capable of translating along the vertical axis Z relative to the manufacturing support 104, or as a variant, the manufacturing support 104 is capable of translating along the vertical axis Z relative to the material deposition track 20.

[0271] In other words, in each material deposition sequence, the manufacturing support translates along the lateral axis between an initial position and a final position relative to the material deposition track, and returns to its initial position at the end of each material deposition sequence.

[0272] Similarly, it is also conceivable not to reset the position of the manufacturing support, but to deposit material on the already deposited material layer in the opposite direction.

[0273] In fact, it is conceivable to manufacture the support member without returning to the initial position to deposit material on the next layer, but starting from the final position of the previous layer and creating the layer in the opposite direction. This can save time as there is no time required to return to the initial position.

[0274] According to another embodiment, the width of the material deposition track 20 is less than the width of the object 106 to be manufactured.

[0275] In this case, during the relative movement of the material deposition track 20 relative to the manufacturing support 104 in the transverse direction Y, each material deposition nozzle 21 to 24 deposits material in a given transverse material line Li with a certain thickness, and after each time a layer of a given transverse material line Li is manufactured (corresponding to the material deposition sequence), the material deposition track 20 is axially translated along the longitudinal axis X by the width of the track 20 relative to the manufacturing support 104, the number of translations being the same as the number of times required to manufacture the first layer including all the material lines Li. These operations are repeated until all the superimposed layers of the required thickness for forming the object 106 to be manufactured are obtained.

[0276] Thus, an entire layer is produced in each material deposition sequence.

[0277] After each material layer Cj (corresponding to the material deposition sequence) is manufactured, the transverse position of the manufacturing support 104 is reset, and a relative movement of the material deposition track 20 relative to the manufacturing support 104 along the vertical axis Z is generated so that the track 20 moves away from the support 104 in the vertical direction, and the layer manufacturing operation is repeated.

[0278] The "initial transverse position" of the manufacturing support 104 means the first transverse position of the manufacturing support 104 relative to the material deposition tracks 20, 30 at which material is first deposited on the manufacturing support 104.

[0279] If the object 106 is manufactured by a plurality of material deposition nozzles 31 to 38 of the material deposition track 30 described in detail with reference to Figure 6 and Figure 7 the widths of the material deposition tracks 30, 30a, 30b are equal to the width of the object 106 to be manufactured, and each material deposition nozzle 31 to 38 is configured to build the entire material layer Cj.

[0280] During relative movement of the material deposition track 30 relative to the manufacturing support 104 in the forward direction (here the lateral direction Y), one of the material deposition nozzles of the material deposition track 30 deposits material on the lateral material line Li of the material layer Cj, and after each material deposition sequence, the material deposition track 30 translates the material line Li axially along the longitudinal axis X relative to the manufacturing support 104, and the manufacturing support 104 is moved to its initial lateral position. These operations are repeated until each material deposition nozzle 31 to 38 deposits material on the entire material layer Cj including all the lateral material lines Li.

[0281] It can be arranged that the material deposition track 30 is capable of translating relative to the manufacturing support 104 along the forward axis (here the lateral axis Y), or as a variant, the manufacturing support 104 is capable of translating relative to the material deposition track 30 along the forward axis (here the lateral axis Y).

[0282] It can be arranged that the material deposition track 30 is capable of translating relative to the manufacturing support 104 along the longitudinal axis X, or as a variant, the manufacturing support 104 is capable of translating relative to the material deposition track 30 along the longitudinal axis X.

[0283] In other words, during relative movement of the material deposition track 30 relative to the manufacturing support 104 in the forward direction (here the lateral direction Y), the material deposition nozzles 31 to 38 are continuously actuated to fabricate a given lateral material line Li. The first nozzle 31 deposits material on the first line L8 according to a first thickness (corresponding to the first material deposition sequence), then the material deposition track 30 axially moves the width of the material line Li along the longitudinal axis X relative to the manufacturing support 104, the first nozzle 31 deposits material on the second line L7, and the second nozzle 32 adjacent to the first nozzle 31 deposits material on the first line L8 according to a second thickness of the layer superimposed on the first line formed by the first nozzle (corresponding to the second material deposition sequence), and so on until each material deposition nozzle fabricates a given layer Cj until the desired geometry of the object 106 to be manufactured is obtained.

[0284] Thus, the first material deposition nozzle 31 produces the first layer C1, the second nozzle 32 produces the second layer C2, the third nozzle 33 produces the third layer C3, and so on until the desired total thickness of the object 106 to be manufactured is obtained. Thus, each of the material deposition nozzles 31 to 38 is configured to build the entire material layer Cj.

[0285] After each material deposition sequence, the manufacturing support is translated along the lateral axis to its initial position relative to the material deposition track.

[0286] This arrangement can use fewer material deposition nozzles compared to depositing material with a nozzle configured to deposit material along a material line Li.

[0287] At this time, the number of material deposition nozzles 31 to 38 depends on the number of material layers to be built.

[0288] Here, the material deposition nozzles 31 to 38 are arranged in rows R1, R2, R3, R4 offset along the vertical axis Z, such that it is no longer necessary to move the material deposition track 30 in the vertical direction relative to the manufacturing support 104.

[0289] In Figure 6 and Figure 7 the illustrated embodiment, the material deposition nozzles 31 to 38 deposit material on the same material line Li with an offset along the longitudinal axis X.

[0290] If the object 106 is manufactured by a plurality of material deposition nozzles 31 to 38 of the material deposition track 30 described in detail with reference to Figure 8 and Figure 9 then the layer Cj is built two laps behind the previous layer.

[0291] If the object 106 is manufactured by a plurality of material deposition nozzles 31 to 38 of the material deposition track 30 described in detail with reference to Figure 10 and Figure 11 then two material deposition nozzles 31a, 31b to 38a, 38b are configured to build an entire material layer including all adjacent lateral lines Li in one thickness. The material layer Cj is built two laps behind the previous layer.

[0292] If the object 106 is manufactured by the material deposition tracks 30a, 30b described in detail with reference to Figure 12 then the additive manufacturing device 10 includes a first actuation system (not shown), the first actuation system being configured to translate the first material deposition track 30a relative to the manufacturing support 104 in the longitudinal direction X parallel to the rotational axis X-X in a first direction across the width of the manufacturing support 104.

[0293] The additive manufacturing device 10 includes a second actuation system (not shown), the second actuation system being configured to translate the second material deposition track 30b relative to the manufacturing support 104 in the longitudinal direction X in a second direction.

[0294] The first direction is opposite to the second direction.

[0295] Thus, the two material deposition tracks 30a, 30b are configured to move in opposite directions relative to the build support 104 along the longitudinal axis X starting from the lateral intermediate plane of the build support 104. The two material deposition tracks 30a, 30b are configured to deposit material together on a single layer Cj.

[0296] Each track 30a, 30b corresponds to one of the tracks described in the reference Figures 6 to 11 description.

[0297] Generally, the build support 104 of the additive manufacturing apparatus 10 and one or more tracks 20, 30, 30a, 30b move relative to each other at least in the longitudinal direction X and / or the vertical direction Z.

[0298] Preferably, the build support 104 is capable of translating along the feed axis (here the lateral axis Y).

[0299] Generally, it can be provided that the build support 104 is capable of moving relative to the tracks 20, 30 of the additive manufacturing apparatus 10 along one to three movement axes (i.e., the vertical axis Z, the longitudinal axis X, and the lateral axis Y).

[0300] As a variant, it can be provided that the build support 104 is fixed relative to the support 12 of the manufacturing apparatus 10.

[0301] If the build support 104 is capable of moving at least along the vertical axis Z and / or along the longitudinal axis X, the tracks 20, 30 of the additive manufacturing apparatus 10 can be fixed relative to the fixed support 12 of the apparatus 10.

[0302] In all embodiments, it can also be provided that the build platform 104 is capable of moving relative to the tracks 20, 30, 30a, 30b about one to three rotational axes A, B, C (defined about the axes X, Y, and Z respectively).

[0303] In all embodiments, it can be provided that the closing devices of certain nozzles are in the closed position to produce a specific geometry of the object to be manufactured.

[0304] The multi-nozzle material deposition tracks enable the deposition of material at selected positions, thereby producing a high-quality geometry of a three-dimensional object (i.e., a tread, a cylindrical object, or any other object (e.g., an object having a parallelepiped shape)).

Claims

1. An apparatus (10) for additive manufacturing of all or part of a three-dimensional object (106, 6, 6') on a manufacturing support (104, 4, 4'), characterized in that, The device (10) comprises: - at least one additive deposition track (20, 30, 30a, 30b) intended to be arranged above the manufacturing support (104, 4, 4'), extending along a longitudinal axis (X) and including a plurality of material deposition nozzles (21 to 24; 31 to 38), each material deposition nozzle being provided with at least one dispensing hole (26), - each of the material deposition nozzles (21 to 24; 31 to 38) includes a closing device (28a) and an actuator (28b), the closing device (28a) being able to move between a closed position of the dispensing hole (26) and a plurality of open positions, the actuator (28b) being for controlling the movement of the closing device (28a) between the closed position and the open positions, - the closing devices (28a) can be controlled independently of one another, - the device (10) further comprises at least: - an actuation system configured to produce a relative translation of the material deposition track (20, 30, 30a, 30b) relative to the manufacturing support (104, 4, 4') in at least a vertical direction (Z) and / or a longitudinal direction (X), and - a drive member (15) of the manufacturing support, which is able to drive the manufacturing support (104, 4, 4') in a forward direction (Y) perpendicular to the longitudinal direction (X), characterized in that the material deposition nozzles (31 to 38) of the material deposition track (30, 30a, 30b) are arranged in the same plane containing the longitudinal axis (X), the longitudinal axis (X) being perpendicular to the forward direction (Y), and the nozzles (31 to 38) being offset relative to one another in the vertical direction.

2. The device (10) according to claim 1, comprising at least one extruder (18), the extruder (18) being connected to the material deposition track (20, 30, 30a, 30b) and supplying a line of molten material to the track (20, 30, 30a, 30b).

3. The device (10) according to claim 2, wherein, The extruder (18) is located centrally and is associated with all the material deposition nozzles.

4. The device (10) according to claim 2, comprising a plurality of extruders, each extruder being associated with at least two material deposition nozzles.

5. The device (10) according to any one of claims 2 to 4, wherein, Each material deposition nozzle (21 to 24; 31 to 38) includes a chamber (25) for receiving molten material from the extruder (18), the chamber (25) being in communication with the dispensing hole (26).

6. The apparatus (10) according to any one of the preceding claims, wherein, The dispensing hole (26) of each of the material deposition nozzles (21 to 24; 31 to 38) has a rectangular or circular cross-section.

7. The device (10) according to any one of the preceding claims, wherein, Each of the closing devices (28a) includes a needle.

8. The apparatus (10) according to any one of the preceding claims, wherein, The material deposition nozzles (21, 22, 23, 24) are arranged in a single row (R1, R2, R3, R4) along the longitudinal direction (X) on the material deposition track (20).

9. The device (10) according to any one of claims 1 to 7, wherein The material deposition nozzles (21, 22, 23, 24) are arranged on a material deposition track (20) in at least two parallel rows (R1, R2, R3, R4) offset along a transverse axis (Y), the transverse axis (Y) being perpendicular to the longitudinal direction (X) and perpendicular to the vertical direction (Z), and each row (R1, R2, R3, R4) comprising at least two material deposition nozzles aligned in the longitudinal direction (X).

10. The device (10) according to any one of the preceding claims, comprising two material deposition tracks (30a, 30b) respectively associated with dedicated actuation systems, the tracks being able to translate in two opposite directions in the longitudinal direction (X).

11. The device (10) according to any one of the preceding claims, wherein, The actuation system is configured to translate the material deposition tracks (20, 30, 30a, 30b) relative to the manufacturing support (104, 4, 4') in the vertical direction (Z) and / or in the longitudinal direction (X).

12. A method for additive manufacturing of all or part of a three-dimensional object (106, 6, 6') on a manufacturing support (104, 4, 4') using a manufacturing device, the manufacturing device comprising at least one material deposition track (20, 30, 30a, 30b) arranged above the manufacturing support (104, 4, 4'), extending along a longitudinal axis (X), and comprising a plurality of additive deposition nozzles (21 to 24; 31 to 38), each additive deposition nozzle being provided with at least one dispensing orifice (26), the material deposition nozzles (31 to 38) of the material deposition tracks (30, 30a, 30b) being arranged in the same plane containing the longitudinal axis (X), the longitudinal axis (X) being perpendicular to the advancing direction (Y), the nozzles (31 to 38) being offset relative to one another in the vertical direction, wherein: - in a material deposition sequence, each of the material deposition nozzles (21 to 24; 31 to 38) deposits extruded material on the manufacturing support (104, 4, 4'), - the closing devices (28a) associated with each of the material deposition nozzles (21 to 24; 31 to 38) are controlled independently of one another to move between a closed position and a plurality of open positions of the dispensing orifice (26) of each nozzle according to the geometry of the three-dimensional object (106, 6, 6') to be manufactured, and in each material deposition sequence, the manufacturing support (104) is translated along the transverse axis (Y) between an initial position and a final position relative to the material deposition tracks (20, 30, 30a, 30b). - After each material deposition sequence, the material deposition tracks (20, 30, 30a, 30b) and the manufacturing support are relatively translated with respect to each other in at least the vertical direction (Z) and / or the longitudinal direction (X), characterized in that the width of the material deposition track (20) is smaller than the width of the three-dimensional object (106, 6, 6') to be manufactured, and in each material deposition sequence, each material deposition nozzle (21 to 24) deposits material in a given material line at a specific thickness, wherein, after each material deposition sequence, the material deposition track (20) is axially translated along the longitudinal axis (X) by the width of the track (20) with respect to the manufacturing support (104, 4, 4'), and these operations are repeated until a first material layer (Cj) including all the material lines (Li) is obtained.

13. The method according to claim 12, wherein: - In each material deposition sequence, each material deposition nozzle (21 to 24) deposits material at the thickness of at least one given material line (Li), and all the material deposition nozzles (21 to 24) deposit material in the first layer corresponding to the width of the three-dimensional object to be manufactured, - After each material deposition sequence, the material deposition track (20) is translated along the vertical axis (Z) with respect to the manufacturing support (104, 4, 4'), and each of the material deposition nozzles (21 to 24) deposits material according to the same given material line (Li), thereby forming a second layer superimposed on the first layer, and these operations are repeated until the desired thickness of the three-dimensional object (106, 6, 6') is obtained.

Images