Additive manufacturing machine and related additive manufacturing method

Abstract

The present invention relates to a machine capable of additively manufacturing parts using high-viscosity resins, comprising: a structure (1); a transport module (2) having a movable support (3) and a displacement mechanism (5) for housing and vertically moving a printing surface; a light source (6); at least one reservoir (11) of material; a material supply module (8) connected to the reservoir (11) of material for applying a layer of printing material onto a conveyor base (9) that conveys the layer of printing material from the material supply module (8) to a printing surface (4) where the layer of printing material is cured; and a fixturing system (10) for fixing and moving the conveyor base.

Description

Detailed Description of the Invention

[0001] [Object of the Invention] The present invention relates to a system for manufacturing parts by additive manufacturing, and in particular to a 3D printer that manufactures parts layer by layer.

[0002] One aspect of the present invention is a machine that can quickly and efficiently manufacture three-dimensional parts layer by layer. Furthermore, the machine according to the present invention makes it possible to use high viscosity resins and filled resins, as well as to obtain multi-material parts.

[0003] Another aspect of the invention is a method for additive manufacturing of three-dimensional parts by additive manufacturing techniques, which method makes use of the machine according to the invention and allows obtaining medium and large sized parts, avoiding the use of large vats of photosensitive printing material.

[0004] BACKGROUND OF THE INVENTION In the 1980s, additive manufacturing technology using stereolithography was invented. This technology works by focusing an ultraviolet beam (laser) from a light source located in the upper part, which solidifies the resin in a resin tank located in the lower part. However, this machine requires high maintenance costs due to the large volume of the resin tank.

[0005] Subsequent improvements to additive manufacturing have been made by EnvisionTec and others, who used a DLP projector as a light source, inverting the elements so that the resin is placed in a reservoir with a transparent or translucent base, and the light source is placed below it. The use of a material reservoir has limitations regarding the use of certain materials and the measurement of the printing volume.

[0006] Most of the solutions found are based on bottom-up manufacturing systems, which limit the printing materials used to low viscosity resins.

[0007] Localized top-down systems involve the use of large vats of printing material, which results in significantly increased costs of use and maintenance.

[0008] Other manufacturing methods have been developed that use transparent substrates. However, these AM systems generally suffer from the same limitations as the systems discussed above due to the use of reservoirs or vats of material, which reduces flexibility in dispensing different types of material or materials, and in dispensing highly viscous materials or materials with added reinforcing materials.

[0009] DESCRIPTION OF THE INVENTION The present invention relates to an additive manufacturing machine that allows the use of high-viscosity printing materials, in particular resins with a viscosity of 2000 cps (mPa*s) or more at 25° C., and materials to which reinforcing materials have been added. Furthermore, the additive manufacturing machine allows the use of different materials for the production of parts, whether they have different mechanical properties or different colors.

[0010] The machine may have different sizes so that it can produce medium and large parts while maintaining the advantage of being able to use high viscosity printing materials with good mechanical properties or high viscosity printing materials with reinforcing materials.

[0011] Additionally, the machine allows for the production of parts that include areas created by consumable support material, reducing the need for modifications to the part to achieve its final geometry.

[0012] Firstly, the machine according to the invention comprises a structure that serves to house all the elements that make up the machine.

[0013] The machine further comprises a transport module, the transport module comprising a movable support and a displacement mechanism connected to the structure.

[0014] The transport module is responsible for making it possible to manufacture a part layer by layer. The transport module is intended to accommodate a printing surface by means of the movable support. The part to be manufactured will be printed on the printing surface. The printing surface can be moved vertically (longitudinal) by the transport module depending on the height of the layer of the part already manufactured. Preferably, the printing surface and the movable support may form a single element.

[0015] The displacement mechanism of the transport module may comprise one or more spindles transmitting a movement guided by a linear displacement guide element connected to the movable support, such that the displacement mechanism generates a vertical movement in the movable support by means of the guide element.

[0016] Furthermore, the transport module may further comprise an auto-leveling mechanism, system or routine having a positioning frame intended to accommodate the printing surface and attached to the movable support so that the positioning of the printing surface can be adjusted relative to the conveyor base. The auto-leveling mechanism, system or routine may be implemented by a mechanism using electronic circuits, sensing elements or programming routines.

[0017] The machine further comprises at least one light source, preferably ultraviolet or visible light, fixed to the structure and preferably located above the work surface, which serves to cure the printing material. The light is preferably configured to generate a light beam having a predetermined shape to cure desired portions of the layer of printing material applied to the part being built.

[0018] The light source may be a projector, screen or laser, precisely calibrated and positioned to provide the appropriate resolution and print area.

[0019] The machine uses a photosensitive printing material that is cured by the light generated by the light source, preferably a high viscosity photosensitive resin or a photosensitive resin filled with a reinforcing material.

[0020] Furthermore, the machine comprises at least one reservoir of material, said reservoir of material being located in the structure and intended to contain the printing material, said reservoir of material storing the printing material and preferably being removable so that the printing material can be easily replaced.

[0021] Furthermore, the machine according to the invention comprises at least one material supply module connected to said reservoir of material, said material supply module intended to apply a layer of printing material onto the conveyor substrate.

[0022] At least one of the material supply modules may comprise a cartridge and a material supply roller for applying a layer of printing material onto the conveyor base, where the material supply roller would be arranged tangentially to at least one rotating element of the fastening system.

[0023] To control the thickness of the layer of printing material applied to the conveyor base, the material supply module may further include a thickness control module, which includes a linearly moving runner connected to the cartridge and the material supply roller, and a supply motor driving the movement of the runner. Displacement of the runner driven by the supply motor can change the distance of the material supply roller from the rotating element of the fixation system, thereby changing the thickness of the layer of material supplied to the conveyor base.

[0024] The conveyor base is replaceable and intended to transport the printing material from the material supply module to the printing surface, and is transparent so that light generated by the light source can pass through the conveyor base and reach the printing material to cure it on the part being built.

[0025] The machine according to the present invention further comprises the clamping system, which comprises one or more clamping elements, at least two rotating elements, and one or more displacement motors. Preferably, the clamping system comprises a central and a movable clamping element and four rotating elements, i.e., two upper and two lower rotating elements. Alternatively, the clamping system may comprise two clamping elements and two rotating elements.

[0026] Preferably, the central and movable fixing elements of the fixing system are located on linear guides and are intended to hold the conveyor base at both ends relative to the structure at a height above and parallel to the work surface, the fixing elements moving alternately in two directions on the linear guides and thereby creating a movement in the conveyor base.

[0027] Preferably, in this case, the conveyor base is connected to the central and movable fixed element by two connecting rods, which are fixed to both ends of the conveyor base, for example by loops or clips, and are connected to the fixed element by two C-shaped fixing elements.

[0028] Alternatively, in the case of two fixing elements, the two fixing elements of the fixing system are located on linear guides and are intended to hold the transparent conveyor base relative to the structure, and the two fixing elements can move on the linear guides to create movement in the conveyor base.

[0029] The fastening system utilizes a plurality of the rolling elements relative to the structure, the rolling elements being intended to act as support points for the conveyor base.

[0030] Preferably, the conveyor base is arranged in an O-shape and is held at both ends by the central and movable fixed element and by a plurality of connecting rods. The conveyor base extends horizontally toward a first rotating element and changes direction by abutting against the first rotating element. The conveyor base then extends vertically (longitudinal) with a specific inclination toward a second rotating element and changes direction again by abutting against the second rotating element. The conveyor base then extends horizontally toward a third rotating element, crossing the work surface, and changes direction by abutting against this rotating element. The conveyor base then extends vertically upward with a specific inclination symmetrical to the downward inclination, and abuts against a fourth rotating element. The conveyor base then extends horizontally and is held at its second end by the central and movable fixed element.

[0031] Alternatively, the conveyor base may be arranged in a U-shape and held at a first end by a first fixed element. The conveyor base extends vertically downward and changes direction by abutting against a first rotating element. The conveyor base then extends horizontally toward a second rotating element and changes direction again by abutting against the second rotating element. The conveyor base then extends vertically upward and is held at a second end by a second fixed element.

[0032] In moving the fixed element, the conveyor base moves, resulting in rotation of the rollers. The movement of the fixed element is controlled by one or more displacement motors connected to the fixed element to move the conveyor base. In moving the conveyor base, the fixed element preferably moves horizontally when there is one fixed element, or vertically in opposite directions when there are multiple fixed elements to move the conveyor base.

[0033] Preferably, when there are four rotating elements, tensioning of the conveyor base is performed by a tensioning system connected to two of the upper rotating elements. The tensioning system allows the two upper rotating elements to move toward or away from each other through movement of a central transverse spindle. When positioning the conveyor base, the tensioning system is compressed, i.e., the rotating elements move closer to each other. Once the conveyor base is positioned, the rotating elements move away from each other until a desired tension is reached, preferably until a motor step loss is detected.

[0034] Alternatively, when there are two said fixing elements, the two fixing elements are clamp-like elements and comprise a lower block and an upper block, the lower block comprising an adjustment screw for engaging the conveyor base and a self-tensioning motor allowing automatic tensioning of the conveyor base, and the upper block comprising a tilting element allowing alignment of the conveyor base.

[0035] The machine of the present invention may further include a material collection module. The material collection module includes an excess material collection tray, a material filter, and a recirculation conduit. The recirculation conduit directs the collected material toward the cartridge or toward the reservoir. The uncured material is directed toward the excess material collection tray. The material from the excess material collection tray is collected by the recirculation conduit and sent to the cartridge or the reservoir, but the material has already been filtered.

[0036] The material collection module further includes a spatula for directing the uncured material toward the material collection tray. The spatula is positioned near the conveyor base and presses against the conveyor base to collect excess material. Preferably, the spatula can be moved toward or removed from the conveyor base. To this end, the material collection module may further include an actuation mechanism for causing vertical displacement of the spatula.

[0037] Furthermore, the machine according to the invention may further comprise a cleaning module intended to clean the top surface of the last manufactured layer of the part being built.

[0038] Preferably, the cleaning module may include two rollers on which a soft material is disposed, a cleaning motor for moving the two rollers, and a cleaning substrate extending annularly over the two rollers, the cleaning substrate being in contact with the two rollers and being driven by the cleaning motor so that it can rotate continuously.

[0039] The cleaning module may include a base, runners, and linear guides for moving the cleaning substrate closer to the part and removing the cleaning substrate when its function has been performed. The runners are connected to the base and move along the linear guides. The base is further connected to the rollers to allow them to move vertically.

[0040] Additionally, the cleaning module may further comprise a waste collection element and a solvent material application element for cleaning the printing surface.

[0041] Additionally, the cleaning module may further comprise one or more radiation sources mounted on the structure, the one or more radiation sources enabling drying of the printing surface.

[0042] The invention further relates to a method for additively manufacturing parts, which allows for the production of additively manufactured parts with high efficiency and precision using the machines described.

[0043] The method according to the invention comprises a first step of providing a conveyor base placed on the fastening system. This step may be performed manually or automatically. Preferably, it is performed manually, where an already used conveyor base is loosened and removed from the structure by disengaging the fastening means(s), and a new conveyor base is placed on the fastening system.

[0044] The conveyor base is then automatically tensioned by the fastening system or the tensioning system. In particular, when the conveyor base is arranged in an O-shape, the tensioning system moves the upper rotating elements to tension the conveyor base. When the conveyor base is arranged in a U-shape, the machine may include a self-tensioning motor responsible for providing accurate tension to the conveyor base.

[0045] Preferably, at this time, the auto-leveling mechanism, system or routine of the transport module is activated to ensure that the printing surface is flush with the conveyor base and remains calibrated for the remainder of the printing process.

[0046] The light source is then activated, which will be used to cure the printed material.

[0047] The material supply module is then positioned at a distance equal to the desired layer thickness of the conveyor base, and if a material supply roller is included, the roller is positioned at a distance equal to the desired layer thickness of the conveyor base.

[0048] Once the material supply modules are positioned, the clamping system is moved to initiate movement of the conveyor base. This is accomplished by alternately moving the clamping element on a horizontal axis parallel to the work surface (left and right) if the conveyor base is configured in an O-shape. If the conveyor base is configured in a U-shape, this is accomplished by simultaneously lowering the first clamping element and raising the second clamping element.

[0049] During the movement of the conveyor base, printing material is supplied to the underside of the conveyor base along a predetermined working length. If material has been supplied along the working length and the movement of the stationary element(s) has not yet ended, this material supply is preferably stopped by the material supply module and the movement of the stationary system is continued until the stationary element(s) reaches a bottom end position, i.e., until the stationary element(s) reaches a position where they cannot move any further without colliding with one of the rotating elements. This material supply is performed by the material supply module located below the first stationary element.

[0050] When the movement of the conveyor base is complete, the transport module moves to raise the work surface to a distance from the conveyor base equal to the thickness of the new layer placed on the conveyor base plus the thickness of the previously produced layer.

[0051] The uncured printing material is then irradiated by the light source, thereby creating a predetermined shape and curing the layer of the conveyor substrate according to the shape, the exposure time in each case being determined by the light source, the type of printing material and the layer thickness.

[0052] Once the layer of the conveyor base is cured, the transport module is lowered and the cured layer is peeled off the conveyor base, leaving behind any uncured excess printing material. The steps of moving the fixture system, supplying printing material, raising the work surface, irradiating the printing material, and lowering the transport module are then repeated to produce successive layers of a part.

[0053] The method may further comprise the additional step of activating the material collection module to remove uncured material, which is recycled by reintroducing it back into the material supply module.

[0054] In a preferred embodiment of the method according to the present invention, a machine is used that includes a first material supply module having a first cartridge containing a first printing material and at least one second material supply module having a second cartridge containing a second printing material. This configuration allows for alternate supply of printing material during each movement of the conveyor base. In this configuration, a first printing module located on one of the sides of the structure contains the first printing material in its cartridge. The first printing material is supplied to the conveyor base when the fixed element(s) move in one direction. Meanwhile, the second material supply module is the material supply module that supplies the second printing material to the conveyor base when the fixed element(s) move in the opposite direction. As a result, one printing material is alternately supplied with another printing material during each movement of the conveyor base. This configuration may include more material supply modules that allow two or more different materials to be used simultaneously.

[0055] In one embodiment, the first printing material and the second printing material may be supplied in a series of layers, such that a layer of the first printing material is placed on top of the first printing material, followed by a layer of the second printing material.

[0056] Alternatively, once the first layer of printing material has been deposited, the transport module may be moved so that the second layer of printing material is deposited at the same height as the first layer of printing material, such that when depositing the second layer of printing material, the transport module is moved toward the conveyor base a distance equal to the set of thicknesses already printed so that the second layer of printing material is added to the same layer as the first layer of printing material.

[0057] The printer of the present invention may preferably include a displacement mechanism connected to the clamping system. When the downward movement of the conveyor base is completed after depositing the first and second materials, the displacement mechanism moves the transport module horizontally toward a new reference position aligned with a secondary supply module, which is similar to the aforementioned supply module but loaded with two new materials. Once the clamping system is repositioned, the described operating cycle is repeated, curing the portions corresponding to each material.

[0058] Alternatively, the printer of the present invention may include a secondary supply module loaded with two new materials and a displacement mechanism connected to the plurality of supply modules. When the movement of the conveyor base is completed after placing the first and second materials, the plurality of supply modules move horizontally to position the secondary supply module at a reference position aligned with the movement of the conveyor base. The same conveyor base is used for both supply modules, and the cleaning system should thoroughly clean the cleaning base. As a result, the materials in the secondary supply module can contact the cleaning base and remain clean.

[0059] The printer according to the invention may further comprise a second conveyor base connected to the secondary supply module, so that the supply of fresh material contained in the secondary supply module can be performed without the need to use a single conveyor base.

[0060] Once the first layer of printing material is deposited, the cleaning module is preferably activated to clean the freshly fabricated surface of the part being built, thereby avoiding contamination of the second layer of printing material.

[0061] Preferably, the printing direction is top-down, with the part being printed from its lower region towards its upper region, starting with the printing surface in the upper part of the printing volume and moving towards the lower part with multiple layers following one another.

[0062] Additionally, the machine generates less waste and uses less conveyor substrate because it is reused after each layer of printing material solidifies on the part being built. Additionally, the printing material recycling system reduces resin usage.

[0063] DESCRIPTION OF THE DRAWINGS In order to supplement the description provided herein and to make the features of the present invention more readily comprehensible, said description is accompanied by a set of drawings which, by way of illustration and not limitation, constitute an integral part of said description, in accordance with a preferred practical exemplary embodiment of the invention, and which show:

[0064] FIG. 1 shows a schematic diagram of a preferred embodiment of the machine according to the invention.

[0065] FIG. 2 shows a schematic diagram of a preferred embodiment of the transport module.

[0066] FIG. 3 shows a front view of a preferred embodiment of the transport module.

[0067] FIG. 4 shows a schematic diagram of a preferred embodiment of the material supply module.

[0068] FIG. 5 shows a schematic diagram of a preferred embodiment of the fixation system.

[0069] FIG. 6 shows a front view of a preferred embodiment of the fastening system.

[0070] FIG. 7 shows a schematic diagram of a preferred embodiment of the material collection module.

[0071] FIG. 8 is a schematic diagram of a preferred embodiment of the additive manufacturing method according to the present invention.

[0072] FIG. 9 shows a schematic diagram of a second preferred embodiment of the machine according to the invention.

[0073] FIG. 10 shows a schematic diagram of a second preferred embodiment of the fastening system according to the present invention.

[0074] Preferred Embodiments of the Present Invention The present invention relates to a machine that allows for the layer-by-layer additive manufacturing of parts. Due to its configuration, the printer according to the invention allows for a reduced consumption of conveyor base (2) and printing material. This is explained below by means of a preferred exemplary embodiment shown in Figures 1 to 10.

[0075] Figure 1 shows a schematic diagram of the entire machine. The printer has a structure (1) on which the different modules are mounted that allow the production of parts by additive manufacturing.

[0076] Specifically, the machine comprises a transport module (4), an ultraviolet light source (10), two reservoirs of material (11), two material supply modules (12), a fixation system (18), and a material collection module (31).

[0077] Its operation is based on the use of a conveyor base (2) which is responsible for transferring the printing material layer by layer to the part.

[0078] FIG. 2 shows a schematic diagram of the transport module (4) of the machine according to the invention.

[0079] The transport module (4) comprises a movable support (5), a printing surface (3) and a displacement mechanism (6). The part to be built is produced layer by layer on the printing surface (3), which is moved by the displacement mechanism (6).

[0080] The displacement mechanism (6) is connected to the movable support (5) and generates an up and down movement in said movable support (5). Furthermore, the movable support (5) is intended to accommodate the printing surface (3), so that when the movable support (5) is moved by the displacement mechanism (6), the printing surface (3) also moves and is placed in a predetermined position to receive a new layer of printing material on the part being produced on said printing surface (3).

[0081] The transport module (4) therefore generates a vertical movement of the printing surface (3) so that the part can be produced layer by layer and that said printing surface (3) can be removed during the material supply process in order to do so safely.

[0082] The displacement mechanism (6) has four spindles (7) through which move four guide elements (8) that hold the movable support (5) of the transport module (4). The guide elements (8) of the displacement mechanism (6) allow the movement of the movable support (5) and the printing surface (3).

[0083] Figure 3 shows a front view of the transport module (4) further equipped with an auto-leveling mechanism (9), which is intended to allow fine adjustment in the positioning of the printing surface (3) relative to the conveyor base (2).

[0084] The UV light source (10), in this case a DLP projector, is intended to generate a light beam having a predetermined shape for curing a printing material on the part to be built, which in this case is a high-viscosity photosensitive resin with a viscosity greater than 2000 cps (mPa*s) at 25°C and curable by UV light.

[0085] The projector is attached to the structure (1) by supports that allow it to be moved in three directions in space in order to precisely calibrate the focus of the light beam it generates, thus achieving a high degree of precision in the production of each layer of the part to be built.

[0086] The machine shown in Figure 1 further comprises two reservoirs of material (11), each intended to contain a printing material, which may be the same or, preferably, different. The two reservoirs of material (11) are fixed to the structure (1) and are refillable.

[0087] Figure 4 shows a front view of the material supply modules (12). Each material supply module (12) of the machine is responsible for supplying printing material, i.e. photopolymer, towards the conveyor base (2). The material supply module (12) in this case comprises a cartridge (13) and a supply roller (14).

[0088] Each material supply module (12) is connected to one of the two reservoirs (11), so that the printing material contained in the reservoirs (11) is supplied to the cartridges (13) of the material supply modules (12).

[0089] Once the printing material is in the cartridge, it is deposited onto the conveyor base 2 using the feed rollers 14 of the material feed module 12. As the feed rollers 14 rotate, they feed layers of printing material onto the conveyor base 2 in a continuous and controlled manner.

[0090] Figure 5 shows the fastening system (18) of the machine according to the invention in a preferred embodiment. The fastening system (18) is intended to hold the conveyor base (2) in place.

[0091] For this purpose, the fastening system (18) comprises two fastening elements (19, 20), two rotating elements, in this case fastening rollers (27, 28), and two displacement motors (25). In this case, the fastening elements (19, 20) comprise an upper block (21) and a lower block (23).

[0092] Figure 6 shows a front view of the fastening system (18), in particular the upper block (21) and the lower block (23) of the fastening elements (19, 20). The upper block (21) of each fastening element (19, 20) is of the clamp type, which makes it possible to hold the conveyor base (2) by means of an adjustable screw (24).

[0093] Each of the fastening elements (19, 20) houses one of the self-tensioning motors (29, 30) of the fastening system (18) in its lower block (23). The self-tensioning motors (29, 30) allow movement of the fastening elements (19, 20) and, therefore, of the conveyor base (2). In addition, the lower block (23) also houses the self-tensioning motors (29, 30). The self-tensioning motors (29, 30) allow the necessary tension to be automatically applied to the conveyor base (2). Furthermore, tilting elements (22) are further arranged in the lower block (23) for aligning the conveyor base (2).

[0094] The fixed elements (19, 20) are intended to move each of the ends of the conveyor base (2), thereby creating a movement in the conveyor base (2). When one of the two fixed elements (19, 20) moves up, the other one moves down the same distance, and vice versa. The movement of the fixed elements (19, 20) is performed along two linear guides (26).

[0095] Furthermore, the fixed rollers (27, 28) of the fixing system (18) function as support points in the path of the conveyor base (2). For this purpose, they are fixed to the structure (1), so that their only degree of freedom of movement is rotation. Furthermore, the conveyor base (2) abuts against both fixed rollers (27, 28), so that when the fixed element (19) located on the left side is lowered and therefore the fixed element (20) located on the right side is raised, the fixed rollers (27, 28) rotate counterclockwise on their axes, allowing the conveyor base (2) to move smoothly. This maintains the U-shape of the conveyor base (2) relative to the structure (1).

[0096] 1 also illustrates the relative positioning of the material supply module 12 with respect to the fixed rollers 27, 28 of the clamping system 18. The supply rollers 14 of the material supply module 12 are positioned tangentially to the fixed rollers 27, 28 of the clamping system 18, and the supply rollers 14 are moved relative to the fixed rollers 27, 28 a distance equal to the desired layer thickness to be deposited by the material supply module 12 onto the conveyor base 2. In this manner, as the supply rollers 14 rotate, they supply a layer of material of controlled thickness onto the conveyor base 2.

[0097] To vary the thickness of the layer of material being fed to the conveyor base 2, the material feed module 12 further comprises a thickness control module 15. The thickness control module 15 comprises a runner 16 and a feed motor 17. The runner 16 is connected to the feed roller 14 and is moved horizontally and linearly by the feed motor 17, thereby varying the thickness of the layer of material being fed.

[0098] FIG. 7 shows a front view of the material collection module (31) coupled to the material supply module (12). The material collection module (31) includes a material collection tray (32), a spatula (33), a recirculation conduit, and a filter. The spatula (33) of the material collection module (31) approaches the surface of the conveyor base (2) when one layer of the part being built has completed curing. The movement of the conveyor base (2) then forces the uncured printing material into contact with the spatula (33). The spatula (33) removes the uncured printing material from the conveyor base (2) and allows it to fall onto the material collection tray (32). Once excess material enters the material collection tray (32), it is directed toward the recirculation conduit and filtered by the filter. The recirculation conduit carries the excess material to a cartridge (13) or reservoir (11) for later reuse.

[0099] FIG. 8 shows a diagram of a preferred embodiment of the additive manufacturing method according to the present invention.

[0100] Figure 8 shows the conveyor base (2) placed on the fixed rollers (27, 28) of the fixing system (18) and tensioned (tensioned) to move with the movement of the fixing elements (19, 20).

[0101] The ultraviolet light source (10) is activated to allow curing of the printed material.

[0102] Next, the position of the material supply module (12) is calibrated to set the thickness of the layer to be supplied, and the outer surface of the supply roller (14) of the material supply module (12) is moved closer to or farther away from the fixed roller (27, 28) of the corresponding fixing system (18).

[0103] Next, the conveyor base (2) starts moving, with the left fixing element (19) lowering and the right fixing element (20) rising. At the same time, the supply roller (14) is activated and begins to rotate, thereby supplying a layer of printing material of controlled thickness onto the conveyor base (2).

[0104] Once a layer of printing material has been fed onto the conveyor base (2) along a predetermined working length, the printing surface (3) is moved upwards by the transport module (4) to a distance from the conveyor base (2) equal to the thickness of the already produced set of thicknesses in the part plus the thickness of the new layer fed onto the conveyor base (2).

[0105] When the printing surface (3) is in that position, the printing material from the conveyor base (2) is irradiated to harden it in a specific way, and then the printing surface (3) is separated by moving it downwards with the transport module (4).

[0106] The movement of the conveyor base (2) resumes in the same direction as in the case of material supply, and at the same time the material collection module (31) is activated, which allows the uncured material to be removed from the conveyor base (2) by means of a spatula (33), which directs the uncured material towards the material collection tray (32) and finally returns it to the reservoir (11).

[0107] Figure 9 shows a schematic diagram of a second preferred embodiment of the machine according to the invention, in which the conveyor base (2) is arranged in an O-shape. The fixing system (18) comprises a central and a movable fixing element (34) and four rotating elements (27, 28, 35, 36), namely two upper rotating elements (35, 36) and two lower rotating elements (27, 28).

[0108] The central and movable fixing elements (34) of the fixing system (18) are positioned on a plurality of linear guides (37), and the central and movable fixing elements (34) hold the conveyor base (2) at both ends relative to the structure (1) at a height higher than the work surface (3) and parallel to the work surface (3). The fixing elements (34) move alternately in two directions, left and right, on the plurality of linear guides (37), thereby generating movement in the conveyor base (2).

[0109] In this case, the base body (2) is connected to the central and movable fixed element (34) by two connecting rods (38, 39), which are fixed to both ends of the base body (2) by clips, and which are connected to the fixed element (34) by two C-shaped fixing elements (40, 41).

[0110] The conveyor base (2) extends horizontally from the central and movable fixed element (34) toward the first rotating element (35), where it changes direction upon contact with the first rotating element (35). The conveyor base (2) then extends vertically downward at a specific inclination toward the second rotating element (27), where it changes direction again upon contact with the second rotating element (27). The conveyor base (2) then extends horizontally across the work surface (3) toward the third rotating element (28), where it changes direction upon contact with the third rotating element (28). The conveyor base (2) then extends vertically upward at a specific inclination opposite to the downward inclination, where it abuts against the fourth rotating element (36). The conveyor base (2) then extends horizontally and is held by its second end against a central and movable fixed element (34).

[0111] FIG. 10 shows a schematic diagram of a second preferred embodiment of the fastening system (18) of the present invention. This diagram shows a machine-provided tensioning system (42) connected to two upper rotating elements (35, 36). The tensioning system (42), in this case, is a scissor-type mechanism (44). The scissor-type mechanism (44) allows the upper rotating elements (35, 36) to move toward or away from each other through the movement of the central transverse spindle (43). When positioning the conveyor base (2), the tensioning system (18) is compressed, i.e., the rotating elements (35, 36) move closer to each other. Once the base (2) is positioned, the rotating elements (35, 36) move away from each other until the desired tension is reached, preferably until a motor step loss is detected. [Brief explanation of the drawings]

[0112] [Figure 1] 1 shows a schematic diagram of a preferred embodiment of a machine according to the present invention; [Figure 2] 1 shows a schematic diagram of a preferred embodiment of a transport module. [Figure 3] 1 shows a front view of a preferred embodiment of a transport module. [Figure 4] 1 shows a schematic diagram of a preferred embodiment of a material supply module. [Figure 5] 1 shows a schematic diagram of a preferred embodiment of a fixation system. [Figure 6] 1 shows a front view of a preferred embodiment of a fastening system. [Figure 7] 1 shows a schematic diagram of a preferred embodiment of a material collection module. [Figure 8] 1 is a schematic diagram of a preferred embodiment of an additive manufacturing method according to the present invention; [Figure 9] 1 shows a schematic diagram of a second preferred embodiment of the machine according to the invention; [Figure 10] 1 shows a schematic diagram of a second preferred embodiment of a fastening system according to the present invention;

Claims

1. 1. An additive manufacturing machine with a top-down printing direction, Structure (1), a transport module (4) comprising a movable support (5) intended to accommodate a printing surface (3) on which components are printed, the movable support (5) moving the printing surface (3) in a vertical direction, and a displacement mechanism (6) connected to said structure (1); At least one light source (10) fixed to the structure (1); at least one reservoir (11) of material located in said structure (1) and intended to contain printing material; a material supply module (12) connected to said reservoir of material (11) and intended to apply a layer of printing material onto a conveyor base (2), said conveyor base (2) intended to convey said printing material from said material supply module (12) to said printing surface (3); a fastening system (18), The fastening system (18) has a U-shaped configuration; two fixed elements (19, 20) located on a plurality of linear guides (26) and intended to hold the conveyor base (2) relative to the structure (1), the conveyor base (2) being intended to be arranged in a U-shape, the two fixed elements (19, 20) comprising: a lower block (23) housing a self-tensioning motor (29, 30) of the conveyor base (2) and engaging with the conveyor base (2); and an upper block (21) comprising a tilting element (22) connected to the lower block (23), the tilting element (22) configured to tilt the lower block (23) relative to the upper block (21) and thereby rotate the lower block (23) to align the conveyor base (2); two rolling elements (27, 28) relative to the structure (1) intended to act as support points for the conveyor base (2), rotating about their own axes to allow the conveyor base (2) to move; one or more displacement motors (25) for moving the two fixed elements (19, 20) to move the conveyor base (2); Equipped with or The fixation system (18) has an O-shaped configuration; a fixing element (34) located on a plurality of linear guides (37) and intended to hold the conveyor base (2) at both ends relative to the structure (1) at a height higher than the printing surface (3) and parallel to the printing surface (3), and intended to move alternately in two directions on the plurality of linear guides (37) to generate a movement in the conveyor base (2), the conveyor base (2) being intended to be arranged in an O-shape; four rolling elements (27, 28, 35, 36) relative to the structure (1) intended to act as support points for the conveyor base (2), including two upper rolling elements (35, 36) and two lower rolling elements (27, 28), which rotate about their own axes to allow the conveyor base (2) to move; one or more displacement motors (25) for moving the fixed elements (34) to move the conveyor base (2); An additive manufacturing machine comprising:

2. 2. The additive manufacturing machine of claim 1, wherein the light source (10) is a projector, a screen or a laser.

3. 2. The additive manufacturing machine of claim 1, wherein the light source (10) is of the ultraviolet or visible light type.

4. 4. The additive manufacturing machine according to claim 1, wherein the transport module (4) comprises an auto-leveling mechanism (9), an auto-leveling system (9) or an auto-leveling routine (9) having a positioning frame that allows adjustment of the positioning of the printing surface (3).

5. 5. The additive manufacturing machine according to claim 1, wherein the displacement mechanism (6) of the transport module (4) comprises one or more spindles (7) transmitting a movement guided by linear guide elements (8) connected to the movable support (5).

6. Machine for additive manufacturing according to any one of the preceding claims, wherein the printing surface (3) and the movable support (5) form a single part.

7. The fixation system (18) has an O-shaped configuration; The conveyor base (2) is connected to the central and movable fixed element (34) by two connecting rods (38, 39), 2. The additive manufacturing machine according to claim 1, wherein the two connecting rods (38, 39) are fixed to both ends of the conveyor base (2) and are connected to the fixing element (34) by two C-shaped fixing elements (40, 41).

8. the fastening system (18) has an O-shaped configuration and further comprises a tensioning system (42); 8. The additive manufacturing machine according to claim 1 or 7, wherein the tensioning system (42) is connected to the two upper rotating elements (35, 36) and is intended to move the two upper rotating elements (35, 36) towards or away from each other through a movement of a central transverse spindle (43).

9. At least one of the material supply modules (12) comprises a cartridge (13) and a material supply roller (14); 9. The additive manufacturing machine according to claim 1, wherein the material supply roller (14) is located in a position tangential to at least one of the plurality of rotating elements (27, 28) of the clamping system (18) when the clamping system (18) has a U-shaped configuration, or in a position tangential to at least one of the plurality of lower rotating elements (27, 28) of the clamping system (18) when the clamping system (18) has an O-shaped configuration.

10. The material supply module (12) further comprises a thickness control module (15); 10. The additive manufacturing machine of claim 9, wherein the thickness control module comprises a runner (16) connected to the cartridge (13) and the material supply roller (14) and moving linearly, and a supply motor (17) driving the movement of the runner.

11. further comprising a material collection module (31) in addition to an excess material collection tray (32), a material filter, and a recirculation conduit; 11. The additive manufacturing machine of claim 9 or 10, wherein the recirculation conduit directs the collected material towards the cartridge (13) or towards the reservoir (11).

12. The material collection module (31) comprises a spatula (33); 12. The additive manufacturing machine of claim 11, wherein the spatula (33) is positioned near the conveyor base (2) so as to press against the conveyor base (2) and collect excess material.

13. The material collection module (31) further comprises an actuation mechanism connected to the spatula (33); 13. The additive manufacturing machine of claim 12, wherein the actuation mechanism enables the spatula (33) to be moved towards or removed from the conveyor base (2).

14. 14. The additive manufacturing machine according to claim 1, wherein the printing material used is a photosensitive resin having a viscosity of 2000 cps (mPa*s) or more at 25°C.

15. Machine for additive manufacturing according to any one of claims 1 to 14, wherein the printing material used is a photosensitive resin filled with a reinforcing material.

16. The additive manufacturing machine according to any one of the preceding claims, wherein the light source (10) is located above a work surface.

17. Further comprising a cleaning module; The cleaning module includes two rollers on which a soft material is disposed, a cleaning motor for moving the two rollers, and a cleaning substrate extending annularly over the two rollers; An additive manufacturing machine according to any one of the preceding claims, which is adapted to rotate continuously.

18. An additive manufacturing method in which the printing direction is top-down, the method utilizing the additive manufacturing machine according to any one of claims 1 to 17, a) providing a conveyor base disposed on said fastening system (18); b) tensioning the conveyor base (2) by means of the fastening system (18); c) activating said light source (10); d) positioning said material supply module (12) at a distance equal to the desired layer thickness of said conveyor base (2); e) moving the fastening system (18) by lowering the first fastening element (19) and raising the second fastening element (20) if the fastening system (18) has a U-shaped configuration, or by linearly moving the fastening elements (34) on the linear guides (37) if the fastening system (18) has an O-shaped configuration; f) feeding printing material onto the conveyor base (2) along the working length from a material supply module (12) located below the first fixing element (19) if the fixing system (18) has a U-shaped configuration, or from a material supply module (12) located below the lower rotating element (27) and / or the lower rotating element (28) if the fixing system (18) has an O-shaped configuration; g) raising the printing surface (3) to a distance from the conveyor base (2) equal to the thickness of the layer already produced plus the thickness of the new layer; h) irradiating the uncured printing material with the light source (10) to create a predetermined shape and cure the layer; i) lowering the transport module (4) to peel the hardened layer from the conveyor base (2); j) repeating steps e) to i); An additive manufacturing method comprising:

19. 19. The additive manufacturing method according to claim 18, when using the additive manufacturing machine according to claim 4, further comprising the step of ensuring that the transport module (4) is flush with the conveyor base (2) by the automatic leveling mechanism (9), the automatic leveling system (9) or the automatic leveling routine (9) prior to the step of activating the light source (10).

20. 20. The additive manufacturing method according to claim 18 or 19, wherein in the step of supplying printing material onto the conveyor base (2), when the printing material has been supplied to the working area of ​​the conveyor base (2) completely, the movement of the fixing system (18) continues without supplying any more printing material.

21. 21. The additive manufacturing method according to any one of claims 18 to 20, when using the additive manufacturing machine according to any one of claims 11 to 13, further comprising the step of operating the material collection module (31) and removing uncured printing material for reintroducing the uncured printing material into the material supply module (12).

22. 22. The additive manufacturing method according to any one of claims 18 to 21, wherein a first cartridge (13) contains a first printing material and at least one second cartridge (13) comprises a second printing material, such that printing material is supplied alternately during each movement of the conveyor base (2).

23. 23. The additive manufacturing method of claim 22, wherein the step of moving the transport module (4) towards the conveyor base (2) in supplying the second printing material is performed up to a distance equal to a set of already printed thicknesses so that the second printing material is added in the same layer as the first printing material.

24. 24. The additive manufacturing method according to claim 22 or 23, when utilizing the additive manufacturing machine according to claim 17, further comprising the step of operating the cleaning module so as to avoid contamination of the plurality of printing materials.

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