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CN-115734864-B - Additive manufacturing machine and related additive manufacturing method

CN115734864BCN 115734864 BCN115734864 BCN 115734864BCN-115734864-B

Abstract

The invention relates to a machine for the additive manufacturing of components using high-viscosity resins, comprising a structural part (1), a transport module (4) with a movable support (5) and a displacement mechanism (6) for accommodating and moving a printing surface in a vertical direction, a light source (10), at least one material reservoir (11), a material supply module (12) connected to the material reservoir (11) and for applying a layer of printing material on a conveyor substrate (2) which transports the layer of printing material from the material supply module (12) to the printing surface (3), wherein it is cured, and a fastening system (18) for fastening and moving the conveyor substrate.

Inventors

  • O. Raventos Sanchez
  • E. Parliarez Garcia

Assignees

  • 巴塞罗那三维打印机有限公司

Dates

Publication Date
20260508
Application Date
20210315
Priority Date
20200313

Claims (20)

  1. 1.A machine for additive manufacturing, wherein the printing direction is of top-down type, comprising: -a structural member (1); -a transfer module (4) comprising a movable support (5) for housing a printing surface (3) on which components are printed, moving said components in a vertical direction, and a displacement mechanism (6) connected to the structure (1); -at least one light source (10) fixed to the structure (1); -at least one material reservoir (11) located in the structure (1) and intended to comprise a printed material; -a material supply module (12) connected to the material reservoir (11) and for applying a layer of printing material on a conveyor substrate (2) for transporting the printing material from the material supply module (12) to the printing surface (3), and -A fastening system (18); has a U-shaped configuration and includes: -a first (19) and a second (20) fixing element on a linear guide rail (26) for holding a conveyor base plate (2) to the structure (1) and for arranging the conveyor base plate (2) in a U-shape, and wherein the first (19) and second (20) fixing elements comprise a lower block (23) for housing a self-tensioning motor (29, 30) of the conveyor base plate (2) and engaging with the conveyor base plate (2), and an upper block (21) comprising a tilting element (22) for aligning the conveyor base plate (2); a second rotating element (27) and a third rotating element (28) with respect to the structural member (1) as support points for the conveyor belt substrate (2), and rotate themselves to enable smooth movement of the conveyor belt substrate (2); two displacement motors (25) for moving the first (19) and second (20) fixed elements to move the conveyor base plate (2), or Has an O-shaped configuration and includes: -a central and movable fixing element (34) located on a linear guide (37) and adapted to hold the conveyor base plate (2) to the structure (1) at both ends, located at a height above the printing surface and parallel to the printing surface (3), and being alternately movable on the linear guide (37) in both directions to create a movement in the conveyor base plate (2), and wherein the conveyor base plate (2) is adapted to be arranged in an O-shape; A set of four rotating elements with respect to the structure (1) comprises a first rotating element (35), the second rotating element (27), the third rotating element (28) and a fourth rotating element (36) acting as support points for the conveyor base plate (2) and rotating itself to enable a smooth movement of the conveyor base plate (2); One or more displacement motors (25) move the central and movable fixed element (34) to move the conveyor base plate (2).
  2. 2. Machine for additive manufacturing according to claim 1, wherein the light source (10) is a projector, a screen or a laser.
  3. 3. Machine for additive manufacturing according to claim 1, wherein said light source (10) is of the ultraviolet or visible type.
  4. 4. Machine for additive manufacturing according to claim 1, wherein the transfer module (4) comprises an automatic leveling mechanism, system or program (9) with a positioning frame, which initiates the positioning of the printing surface (3) to be adjusted.
  5. 5. Machine for additive manufacturing according to claim 1, wherein the displacement mechanism (6) of the transfer module (4) comprises one or more finger shafts (7) and the guiding element (8) enables movement of the movable support (5) and the printing surface (3).
  6. 6. Machine for additive manufacturing according to claim 1, wherein the printing surface (3) and the movable support (5) form a single element.
  7. 7. Machine for additive manufacturing according to claim 1, wherein the fastening system (18) has an O-shaped configuration, and wherein the conveyor base plate (2) is connected to a central and movable fixing element (34) by two connecting rods (38, 39) fixed to both ends of the conveyor base plate (2) and connected to the central and movable fixing element (34) by two C-shaped fixing elements (40, 41).
  8. 8. Machine for additive manufacturing according to claim 1, wherein the fastening system (18) has an O-shaped configuration and further comprises a tensioning system (42) connected to the first rotating element (35) and the fourth rotating element (36) and for bringing the first rotating element (35) and the fourth rotating element (36) towards or away from each other by movement of a central transverse finger shaft (43).
  9. 9. Machine for additive manufacturing according to claim 1, wherein at least one material supply module (12) comprises a drum (13) and a material supply roller (14), located tangential to at least one of the second rotating element (27) and the third rotating element (28) of the fastening system (18).
  10. 10. The machine for additive manufacturing according to claim 9, wherein the material supply module (12) further comprises a thickness control module (15) comprising a runner (16) connected to the cartridge (13) and the material supply roller (14) and moving linearly, and a supply motor (17) driving the runner to move.
  11. 11. Machine for additive manufacturing according to claim 9, comprising, in addition to a surplus material collection tray (32), a material collection module (31), a material filter and a recirculation duct, directing the collected material to the cartridge (13) or to the reservoir (11).
  12. 12. Machine for additive manufacturing according to claim 11, wherein the material collection module (31) comprises a spatula (33) placed near the conveyor base plate (2) so that it presses the base plate to recover the excess material.
  13. 13. Machine for additive manufacturing according to claim 12, wherein the material collection module (31) further comprises an activation mechanism connected to the spatula (33) enabling the spatula to be brought close to or removed from the conveyor base plate (2).
  14. 14. The machine for additive manufacturing according to claim 1, wherein the material used is a photosensitive resin, and the viscosity at 25 ℃ is greater than or equal to 2000 mPa s.
  15. 15. The machine for additive manufacturing according to claim 14, wherein the material used is a photosensitive resin filled with a reinforcing material.
  16. 16. Machine for additive manufacturing according to claim 1, wherein the light source (10) is located above the printing surface (3).
  17. 17. The machine for additive manufacturing according to claim 1, further comprising a cleaning module including two rollers having a soft material provided thereon, a cleaning motor for moving the rollers, and a cleaning substrate extending in a circle onto the two rollers so as to be continuously rotatable.
  18. 18. A method of manufacturing an additive using the machine for additive manufacturing according to any one of claims 1 to 17, wherein the printing direction is of a top-down type, comprising the steps of: a) Providing a conveyor belt substrate (2) placed in a fastening system (18); b) -tensioning the conveyor belt substrate (2) by means of the fastening system (18); c) Activating the light source (10); d) -placing a supply module (12) at a distance equal to the required layer thickness of the conveyor substrate (2); e) -moving the fastening system (18), lowering the first fixing element (19) and lifting the second fixing element (20) when the fastening system (18) has a U-shaped configuration, or linearly moving the central and movable fixing element (34) on a linear guide (37) when the fastening system (18) has an O-shaped configuration; f) -supplying printing material on the conveyor base plate (2) along a working length from a material supply module (12) located under the first stationary element (19) when the fastening system (18) has a U-shaped configuration, or-supplying printing material on the conveyor base plate (2) along a working length from a material supply module (12) located under the second rotating element (27) and/or the third rotating element (28) when the fastening system (18) has an O-shaped configuration; g) Lifting the printing surface (3) to a distance from the conveyor belt substrate (2) equal to the thickness of the layer produced plus the thickness of the new layer; h) Irradiating the uncured printed material by means of said light source (10) to produce a predetermined shape, a cured layer; i) Lowering the transfer module (4) to peel off the cured layer from the transfer belt substrate (2), and J) Repeating steps e) to i).
  19. 19. The method according to claim 18, further comprising a step prior to activating the light source (10) of ensuring coplanarity of the conveyor module (4) with the conveyor base plate (2) by means of an automatic leveling mechanism, system or program (9).
  20. 20. Method according to claim 18, wherein in the step of supplying material on the conveyor substrate (2), the movement of the fastening system (18) continues as soon as printing material is supplied at the working area of the conveyor substrate (2) without supplying more printing material.

Description

Additive manufacturing machine and related additive manufacturing method Technical Field The invention pertains to a system for producing components by additive manufacturing. In particular, it relates to 3D printers that produce parts layer by layer. The object of the present invention is a machine capable of producing three-dimensional parts quickly and efficiently layer by layer. In addition, the machine of the invention is capable of using high viscosity resins and filled resins, as well as obtaining multi-material parts. Another object of the present invention is a method for additive manufacturing of three-dimensional parts by additive manufacturing technology, which makes use of the machine of the present invention and enables to obtain large and medium-sized parts, avoiding the use of vat photosensitive printing materials. Background Additive manufacturing techniques using stereolithography were invented in the 80 s of the 20 th century and operated by a light source located at the top which focused an ultraviolet light beam (laser) through which the resin located in the lower resin tank was cured. However, these machines are costly to maintain due to the large volume of the resin tank. Subsequently, additive manufacturing was improved, for example, envisionTec implemented by the company using a DLP projector as the light source and reversing the elements, placing the resin in a reservoir with a transparent or translucent base, with the light source in its lower portion. For the use of certain materials and measurement of print volume, there are limitations to the use of material reservoirs. Many of the solutions found are based on bottom-up manufacturing systems that limit the use of printing materials to low viscosity resins. In the case of localized top-down systems, the systems involve the use of vat printing material, which greatly increases the cost of use and maintenance. Other manufacturing methods using transparent substrates have also been found, however, in general, due to the use of reservoirs or vat materials, the additive manufacturing systems developed suffer from the same limitations as previously discussed systems, which reduces the flexibility of supplying different types of material or materials, even high viscosity materials or materials loaded with reinforcing materials. Summary of The Invention The invention relates to a machine for additive manufacturing, which is capable of using high-viscosity printing materials, in particular resins having a viscosity at 25 ℃ of greater than or equal to 2000 mPa s), and materials loaded with reinforcing materials. Furthermore, it is possible to manufacture the components from different materials, whether they are materials with different mechanical properties or materials of different colours. The machine can be of different dimensions so that large and medium-sized components can be produced, maintaining the advantage of using high-viscosity printing materials with good mechanical properties, even reinforcing materials. Furthermore, the machine is capable of manufacturing components, including areas produced using consumable support materials, thereby reducing the need to modify the components to achieve a final geometry. The machine of the invention comprises firstly a structural member which will be responsible for housing all the elements that make up the machine. The machine further comprises a transfer module which in turn comprises a movable support and a displacement mechanism connected to the structural member. The transfer module will be responsible for enabling the layer-by-layer production of the components, which transfer module is intended to receive the printing surface by means of the movable support, on which the components to be manufactured are to be printed. The transfer module thus enables the printing surface to be moved in the vertical direction, depending on the height of the component layers that have been produced. Preferably, the printing surface and the movable support may form a single element. The displacement mechanism of the transfer module may comprise one or more finger shafts transmitting movements guided by linear displacement guide elements connected to the movable support. Thus, the displacement mechanism generates a vertical movement in the movable support by means of the guide element. The conveyor module may further comprise an auto leveling mechanism, system or routine with a positioning frame for receiving the printing surface and connected to the movable carriage to enable adjustment of the positioning of the printing surface relative to the conveyor substrate. The auto-leveling mechanism, system, or routine may be performed by a mechanism, an electronic device, a sensing element, or a programmed routine. The machine further comprises at least one light source, preferably ultraviolet or visible light, fixed to the structure, preferably above the work surface, responsible for curing the printed mat