CN203805319U - Additive fabrication device - Google Patents

Abstract

The utility model aims to provide an additive fabrication device which is provided with an effective reversion mechanical device to reverse a foil guide roller. Therefore, on one hand, a foil guiding system comprises the flexible foil guide roller, a support system and a support layout structure, wherein the support system is arranged to support the guide roller, and comprises an end part locking element used for locking the guide roller axially; the support layout structure is used for defining support positions, enables the guide roller to bend during supporting and splicing, and is spliced with the outer surface of the guide roller in such a manner that the guide roller bent between at least two supporting positions in the same rolling direction. The flexible guide roller connected with external support is used for replacing the fixed shaft layout in the prior art, and can be adjusted to a foil moving direction more easily.

Description

Add manufacturing device

technical field

The utility model belongs to the field of mechanical design. In particular, the invention relates to efficient mechanical means to control the movement of foils used in additive manufacturing. The utility model provides an additive manufacturing device, which has an effective reversing mechanism to reverse the direction of the foil guiding roller. the

Background technique

In additive fabrication processes with high imaging resolution (50 microns or higher in some cases) that utilize a removable carrier foil to hold the liquid build material, it is required that the carrier foil not wrinkle or overly stretch. In certain processes, this is particularly challenging because the carrier foil must be fixed at the current imaging location while moving elsewhere in the additive manufacturing process to allow simultaneous imaging and recoating. Any wrinkling or unintended stretching of the foil is undesirable in any foil-based additive manufacturing process. the

Additive manufacturing processes using UV transparent carrier foils are known. For example, US 6,557,452 to Fudim uses a foil to deliver liquid build material to the imaging site. The liquid build material is imaged and becomes solid after reaching the imaging site. The solid adheres to the previously formed layer of the tangible object, and the foil is then moved to deliver additional liquid build material to the imaging site to form the next solid layer. This process is repeated to build solid three-dimensional objects. Similarly, US7,467,939 and US7,731,887 to 3D Systems, Inc. disclose foil based additive manufacturing processes. In each of these processes, the foil remains fixed while the liquid build material is imaged. the

In an additive manufacturing process, a liquid build material can be imaged at one location while the foil is moved at another location. This process (disclosed in WO2010/074566 belonging to TNO) requires the foil to remain stationary and wrinkle-free at the imaging location while the foil moves elsewhere. the

In foil-based additive manufacturing processes, it is important that the foil does not move, wrinkle, or stretch excessively in any direction at the imaging location. This difficulty is compounded when the system is capable of moving in both directions. the

Therefore, there is a need for an additively manufactured mechanism for allowing wrinkle-free movement of foils, especially in systems capable of bi-directional movement. the

Contents of the invention

An efficient mechanical device for controlling the movement of foils used in additive manufacturing has been invented. According to an aspect, an additive manufacturing apparatus comprises a reciprocating foil guiding station (180) comprising: an energy source (90) arranged for at least partially curing a layer of curable material At least part of a cross pattern of said curable material layer disposed on the foil (11) and in contact with a tangible object; and Foil guiding system comprising: a flexible foil guiding roll (4); and a support system (1) capable of changing and and/or reverse the curvature of said flexible foil guiding roll (4) and said support system is arranged in contact with said flexible foil guiding roll (4) for guiding through said foil The movement of the stage (180) along the tangible object (50) guides the foil (11) comprising the layer of liquid resin (30) to or out of said contact surface (181) for contact with said contact surface (181). In contact with a tangible object (50), the foil includes a transport layer and a structural layer, the transport layer includes polyolefin or fluoropolymer, and the structural layer includes a semi-crystalline thermoplastic polymer, wherein the flexible foil Guide rollers are in contact with the conveying layer of the foil or the structural layer of the foil. the

Specific embodiments of the invention are described in the remainder of the specification. These and other aspects of the invention will be elucidated and apparent by reference to the embodiments described hereinafter. the

Description of drawings

Further details, aspects and embodiments of the invention will be described, by way of example only, with reference to the accompanying drawings. the

Fig. 1 schematically shows a cross-sectional side view of an example of an embodiment of the system according to the present invention;

Figure 2 shows the embodiment of Figure 1 in more detail in a foil-guided layout;

Figure 3 schematically shows a perspective side view of another embodiment;

Figure 4 shows a side view of a detail of the embodiment in Figure 3;

Figure 5 shows the details of the roller assembly; and

Figure 6 shows an embodiment of a foil guiding system incorporated in an additive manufacturing device. the

Detailed ways

According to an aspect, by arranging curved rollers, in particular roller shafts, instead of rigid forms in flexible forms in which the curvature of the rollers can be completely reversed, it is possible to properly control the foils used in the reciprocating additive manufacturing process. In one embodiment, the roller may be provided as a one-piece rod. The curvature can be changed with relatively small forces, and in some embodiments the curvature can even be changed (only) with The force provided by the drag force changes. the

The flexible roll arrangement associated with the external support of the presently claimed aspect of the utility model replaces the fixed roll arrangement of the prior art. This flexible roller arrangement can be easily adjusted to the direction of foil movement. Furthermore, the foil guiding system allows a complete reversal of the direction of the rolls without wrinkling of the foil. the

A known solution to foil wrinkling in a web winding process is to use curved rolls (see eg GB1019958), where the rolls are flexible and rotate around an inflexible curved axis. The bulge of the curved portion points in the direction of the sheet movement. By friction between the sheet and the roll surface, the sheet is stretched in the transverse direction between the point where it initially contacts the roll and the point where it leaves the roll, and wrinkles are eliminated over the area extending from the roll in the direction of foil motion. Another publication is known from EP0431275, which shows a mechanism for varying the deflection angle to produce the desired extension. However, no reversal of the foil orientation is expected. In US3248031 a bending roll is disclosed which can be bent in multiple directions by means of the disclosed bearing system. However, the prior art has not anticipated multi-roll equipment that allows direction reversal in an additive manufacturing setup. the

Figure 1 schematically shows a cross-sectional side view of an embodiment of a system 1 according to aspects of the present invention. As can be seen from the figure, the outer support bearing portion is provided in the form of a flat surface 2 engageable with the outer surface 3 of the roller 4 . The surface 2 supports the bending roll 4 on its outer surface 3 . The bent state means that the roll has a certain degree of flexible springback, wherein the roll is bent into a curve under a certain stress. The deformation can be elastic, which is advantageous in terms of energy savings, or slightly inelastic. The surface 2 thus enables a rolling movement of the guide roller 4 relative to the surface 2 in a curved state, so that the roller can bend between at least two bearing positions A, B in correspondence with the rolling directions P, Q. In the first foil conveying direction P, the roller is curved upwards at a first bearing position A, and in the opposite foil conveying direction Q, the roller is curved downwards with a curvature B reversed relative to the first bearing position. If a variation of the foil velocity is applied in both directions P, Q, the support position can be adjusted and does not need to be symmetrical. Thus, the bearing arrangement 1 allows the curvature of the roller shaft 4 to vary along the path on the bearing surface 2 . Thus, one or more rollers 4 are provided with a reversible curvature, wherein the curvature is reversed when the foil conveying directions P, Q are reversed. It should be noted that conventional layouts of non-flexible curved rollers may cause wrinkling during reversal of the foil feed, and curves that are raised in the direction of motion may cause wrinkling when the bending is held fixed and the direction of motion is reversed relative to the humping. the

Figure 2 shows the embodiment of Figure 1 in more detail in a foil guided layout. Here, the support structure 5 is arranged to support an additional rigid roll 6 in the vicinity of the bending roll 4 . The support structure 5 also provides a locking structure 7 for axially locking the bending roll 4 . the

The locking structure 7 may be fixed relative to the support structure 5 and may comprise a bearing arranged to be able to twist about its center point as the direction of the axis changes as the roll 4 is bent by it. The bearings may be of the self-aligning ball bearing type, which allows for misalignment between the inner and outer rings. Thus, the flexible roller 4 can be locked between the end locking structures 7 of the axially locked roller 4 . The rigid roll 6 is formed as a foil guiding element which guides a foil (not shown) towards and leads out of a contact area arranged on one side of the bending roll 4 (and explained further below) . In some embodiments, the guide element 6 may be a non-rotatable guide forming the edge of the contact surface. the

Fig. 3 schematically shows a perspective side view of other embodiments of aspects of the present invention. In this embodiment, a plurality of support elements 20 , 21 , 22 define a support contact for the roller 4 . While the embodiment of Figure 2 may be provided with a passive support arrangement 1 where the bending force is derived from the tension of the sheet on the roll (as further clarified in connection with the arrangement of Figure 5), preferably, the force that produces (the change in) the curvature It is actively obtained from an actuator 8 (eg of pneumatic type). The controller 9 is arranged to control the actuator 8 in correspondence with the rolling directions P, Q. The roller 4 is locked axially by the locking structure 7 and has two intermediate bearing contacts 20 , 22 which passively follow the bending movement of the roller when the central bearing is actuated. For a particular desired bending curvature, multiple actuators may be positioned along the flexible roller. the

Figure 4 shows the active support arrangement 10 in more detail. The bearing 21 provides bearing contact via rollers 210, 211 along part of the circumference of the rollers. In this way, the roller 4 is embedded in the support 21 and is held in a fixed support position by the pressing force of the foil 11 defined by the support contacts 210, 211 which are in contact with the outer surface of the roller 4. The roller 4 is engaged and partially embedded between the support rollers 210 , 211 . Since the roller 4 is embedded in the support structure 21 , the active bearing actuation means 9 define the range of bending movement and the outer stops of the roller 4 . Schematically, the roller 4' is indicated at position B together with the moving foil 11' to illustrate the bending movement of the roller between positions A and B, forcibly provided by the movable support 21. the

Thus, the actuator 8 is arranged for moving the support element 21 to provide a forced bending movement of the roller 4 between (at least) two support positions A, B. the

Although in theory actuation may be provided by any linear or other actuation arrangement, in a preferred embodiment the actuator 8 comprises a rotatable arm 80 which enables at least one support element 21 to move between at least two support positions A , B to rotate between. A linear pneumatic actuator 81 is coupled to a rotatable arm 80 carrying the support 21 partially embedding the flexible roller 4 . By pneumatic actuation, the arm 80 is rotated between the two support positions A, B, and by the embedding arrangement the flexible roller 4 is forced to bend between the two support positions A, B, while the support 21 allows the roller 4 to flex. rolling motion. In an embodiment, the bearing 21 may be provided by a ball, a cylinder or a suitable lubricated structure of a fixed surface. The rigid roller structure 6 is supported in a support structure with external bearings to allow rolling motion. The rotatable arm 80 bends the curvature of the flexible roller 4 from an upper position A when the foil movement is upward in the P direction to a lower position B when the foil movement is downward in the opposite Q direction. The lower position B is schematically indicated by dashed lines. the

In an embodiment, the tension and/or displacement in the foil (11) can be determined, for example, by measuring the reaction force 2100 of any of the backup rolls (210, 211) and/or the difference in force between the backup rolls 210, 211 Measurement. The tension and/or displacement of the foil (11) may be controlled by the controller 801 in response to measurements of tension and/or displacement in the foil, for example by increasing or decreasing the curvature via control via the actuator 81 or by a rotatable arm (80 ) is adjusted by appropriate outward or inward movement 800 in the direction of the arm. the

The passive roller assemblies 22, 20 as disclosed in the embodiment of FIG. the

FIG. 5 shows an alternative driven roller assembly 20 . Passive means that the assembly follows the bending motion of the roll when the central support is actuated and/or when the roll is bent by the drag force of the foil. On the contrary, an active bearing arrangement means supplying an actively provided force (over and above the drag force) to force the bending movement of the actuating roller 4 . the

While a properly lubricated surface 2 provides frictional support, bearing contact can also be provided by rolling elements 212 arranged on locking structures 213 that engage the guide rollers 4, wherein the locking structures 213 limit the curvature of the roll 4 bends. scope. For example, end locking structures 213 are provided at one or both ends of the desired range of bending, thereby providing locking member 213 that is fixed relative to support system 20 . the

The rollers 4 can be provided as metal rods, eg steel rods. In an embodiment, the rod is hollow. In another embodiment, the rod is solid. The stiffness of the rollers is small enough to allow bending without too much force, yet large enough to define a large enough bend radius for the foil to get a gently bent shape with only a few supports. The surface 40 of the roller 4 must be hard enough to be suitable as a bearing surface for flexible support. When only a few flexible bearings are used, eg ball bearings 210, 211 each having an axial length of a few millimeters, the roller surface 40 will be very little wear-resistant. When using friction bearings 2, where the rod can be supported over considerable lengths, the surface must still be wear resistant, but now the load conditions are different: low load, but on a larger surface, and the contact is not rolling but mobile. the

The roll surface 40 may be provided with a treatment or a layer or a texture (roughness) to provide a sufficiently high coefficient of friction between the roll 4 and the foil material 11 and/or to make the roll surface more wear resistant. the

Reference is now made to Fig. 6, which shows an additive manufacturing system 100 incorporating aspects of the flexible guidance system 1 disclosed in detail in the previous figures. The system 100 comprises an energy source 90 for curing a predetermined area 51 of the liquid layer 30 adjoining the foil 11 to obtain a solid layer 52 of the tangible object 50, the solid layer thus having a predetermined shape. On the foil 11 the liquid layer 30 is formed with a limited height to be in contact with the tangible object 50 . the

Furthermore, the reciprocating foil guide table 180 may be provided with a contact surface 181 in contact with the foil 11 and includes a pair of upper and lower foil guides 6, 60 on the introduction side of the contact surface 181 and the pull-out side of the contact surface 181, such that The flexible foil guide roller 4 is arranged between this pair of guides, the lower foil guide 60 defining a foil height position at a distance H0 from the contact face 181 at foil height H. Figure 6-1 illustrates a plan view of the foil 11, wherein the foil 11 is guided through the contact surface 181 while being stretched in the transverse direction by the bending roll 1 of the supporting arrangement 1. In order to keep the foil 11 wrinkle-free, a flexible guide roll is placed as the first guide roll 4 on the lead-in side of the region 181 and a second flexible guide roll 4' is placed on the pull-out side; the foil 11 is placed on the first flexible guide The rollers 4, 4' are drawn on both and the foil 11 is moved in a first direction P such that the foil 11 remains in contact with the flexible guide rollers 4, 4', wherein the first flexible guide roller and the second flexible guide roller have a first Curvature (A). In a direction of movement Q opposite to the first direction (see Fig. 6-2), the flexible guide rollers 4, 4' have a second curvature B opposite to the first curvature A. the

Thus, the foil 11 can be guided to or from the contact surface 181 such that movement along the tangible object 50 by the foil guide table 180 allows the resin on the foil to come into contact with the tangible object 50 while contact between the resin layer and the tangible object 50 is achieved. The foil 11 remains fixed relative to the tangible object 50 during object contact. It should be noted that under this condition the foil moves relative to the stage 180 in opposite directions previously indicated as P and Q. In an embodiment, the movement of the foil (11) is blocked at both ends (A and B). the

In an embodiment, the foil comprises a transport layer comprising a polyolefin or a fluoropolymer and a structural layer comprising a semi-crystalline thermoplastic polymer. the

According to a first aspect of the presently claimed utility model, the flexible multilayer substrate comprises at least a transport layer and a structural layer, and is thus a multilayer substrate. A flexible multilayer substrate must have at least two layers. In some embodiments, the flexible multilayer substrate has two layers, and in other embodiments, the flexible multilayer substrate has three or four layers. There is no practical limit to the number of layers in a flexible multilayer substrate, as long as the substrate does not reduce the effectiveness of the additive manufacturing process. For example, in some cases, the addition of too many layers may reduce the radiation transparency of the flexible multilayer substrate such that sufficient actinic radiation cannot be delivered to the radiation curable resin. Similarly, there is no practical limit to the thickness of flexible multilayer substrates, as long as the thickness does not bring too much negative impact on the construction of three-dimensional objects. In an embodiment, the flexible multilayer substrate has a thickness of at least 20 microns. In an embodiment, the thickness of the flexible multilayer substrate is from about 50 microns to about 350 microns. In an embodiment, the thickness of the flexible multilayer substrate is from about 20 microns to about 250 microns. In an embodiment, the thickness of the flexible multilayer substrate is from about 50 microns to about 250 microns. In another embodiment, the thickness of the flexible multilayer substrate is from about 90 microns to about 160 microns. the

In an embodiment, each layer of the flexible multilayer substrate is at least 10 microns thick. In an embodiment, each layer of the flexible multilayer substrate is at least 20 microns thick. In an embodiment, the transport layer is from 10 to 100 microns thick and the structural layer is 10 to 250 microns thick. In an embodiment, the transport layer is from 10 to 250 microns thick and the structural layer is 30 to 200 microns thick. the

The flexible multilayer substrate includes a transport layer and a structural layer. The transport layer is used to contact the radiation curable resin. Thus, the delivery layer should have the desired properties for contacting the radiation curable resin and have properties that allow the desired separation from the as-cured layer of the radiation curable resin. Structural layers provide structural integrity. For example, the structural layer has certain improved physical properties compared to the physical properties of the transport layer. The transport layer is thus used to contact the radiation curable resin, and the structural layer is used to provide structural integrity, the structural and transport layers being secured to each other. For example, a transport layer can be pinned directly to a structural layer, or it can be pinned to an intermediate item that is pinned to a structural layer. the

The transport and structural layers and other layers (if desired) of the flexible multilayer substrate can be secured using methods known in the art such as coextrusion, lamination, and heat sealing. Any feasible method can be used to fix the layers, as long as the method is compatible with the materials chosen for the various layers of the flexible multilayer substrate and is capable of forming a flexible multilayer substrate that will allow three-dimensional objects to be built via additive manufacturing processes. The fixation method used must result in a flexible multilayer substrate of substantially uniform thickness with little or no wrinkling. The flexible multilayer substrate should have low internal stress to avoid warping of the flexible multilayer substrate, and should be substantially flat to allow precise construction of three-dimensional objects. Lamination requires the use of adhesives or other substances to hold the layers in place. Heat sealing involves heating a layer of the flexible multilayer substrate to an appropriate temperature and then pressing the layer to another layer over the flexible multilayer substrate to secure the layers. the

Coextrusion methods to form flexible multilayer substrates may require the use of tie-layers. The mating layer is the thin material that holds the coextruded layers together. A suitable material for the mating layer is a polyolefin grafted with maleic anhydride, such as from of Or Exxelor( ^TM) . The mating layer should be chosen to ensure sufficient adhesion to prevent delamination of the two layers during the additive manufacturing process, and without any significant impact on the radiation transmission properties of the combined substrate.

For lamination methods to form flexible multilayer substrates, surface treatments may be required to adequately secure the layers of the flexible multilayer substrate to each other. In order to obtain good adhesion between the layers of the flexible multilayer substrate, surface treatments may be required to introduce reactive groups on the surface of the flexible multilayer substrate so that the layers of the flexible multilayer substrate are sufficiently fixed to each other. the

In an embodiment, corona treatment or other plasma treatment is performed on the layers of the flexible multilayer substrate prior to adhesion. Corona treatment is a surface modification technique that uses low-temperature corona discharge plasma to change the properties of the surface. Corona plasma is generated by applying a high voltage to a sharpened electrode tip that forms a plasma at the end of the sharpened tip. A linear array of electrodes is typically used to form a curtain of corona plasma. In another embodiment, the layer of the substrate is chemically treated before the layer of the substrate is fixed to another layer of the substrate. The surface treatment may be performed on only the first layer of the transport layer, or on the contacting sides of both the transport layer and the structural layer, or other different layers of the flexible multilayer substrate. the

For lamination methods to form flexible multilayer substrates, adhesives must be used to secure the transport and structural layers. The transport and structural layers can be fixed using adhesives that do not have any significant effect on the radiation transmissive properties of the combined flexible multilayer substrate. Suitable adhesives for lamination are usually two component polyurethane adhesives. However, the use of polyurethane is not limited. Examples of other possible adhesives are maleic anhydride modified polyethylene, acrylic resins or two-component epoxies (water or solvent based) among others. the

In general, it is not desirable to form a flexible multilayer substrate by coating a first material on a second material. Coating may result in a surface that is not uniform in size or consistency due to differences in curing or drying of the coating material. In addition, coatings may be less resistant to scratching or scuffing and, compared to flexible multilayer substrates that include polyolefin or fluoropolymer transport layers and structural layers of semi-crystalline thermoplastic polymers, tend to more likely to wear out. the

Furthermore, it has been found that flexible multilayer substrates comprising a delivery layer formed by a coating process have substantially reduced durability compared to multilayer substrates comprising polyolefin or fluoropolymer delivery layers. During testing of coated substrates, it was found that the silicone layer coated on top of the PET structure layer was not durable, as the cured radiation curable resin was observed to be much more flexible after only a few hundred days of construction. Adhesion to the substrate. It has thus been found that coextrusion and lamination methods of securing the transport and structural layers provide more robust flexible multilayer substrates. the

According to a first aspect of the presently claimed invention, the flexible multilayer substrate comprises a polyolefin or fluoropolymer transport layer. The delivery layer has properties that allow for acceptable application of the radiation curable resin and release of the freshly cured layer. The transfer layer must not result in any substantial dewetting of the radiation curable resin before the radiation curable resin applied on the transfer layer is cured. The transfer layer must not adhere to the newly cured layer so that the step of separating the newly cured layer from the substrate does not exhibit cohesive failure. Furthermore, the use of the delivery layer enables the radiation curable resin to be protected from damage by the structural layer, and the structural layer is relied upon to protect the structural layer from damage to the radiation curable resin. Some polymeric construction layers may contain significant amounts of moisture. Moisture in certain polymers that may comprise structural layers, such as polyamides and polyesters, may cause strong acids that are generated upon curing of certain radiation curable resins to promote hydrolysis of the substrate. By using a polyolefin or fluoropolymer transport layer in the substrate, this reaction is eliminated since it is impossible for the acid to reach the structural layer. the

In an embodiment, the transport layer is polyolefin. In other embodiments, the transport layer is branched low density polyethylene (LDPE), linear low density polyethylene (LLPE or LLDPE), high density polyethylene (HDPE), highly branched polyethylene, or a molecular weight typically higher than 1× 10 ⁶ g/mol of ultra-high molecular weight polyethylene (UHMWPE). In other embodiments, the transport layer is a plastic, such as a copolymer of ethylene and octene, polymethylpentene, and the like. In other embodiments, the transport layer is a polymer of ethylene, propylene, butene, hexene, octene, norbornene, styrene, or copolymers and mixtures thereof. In an embodiment, the transport layer is a high ethylene grade vinyl norbornene copolymer, such as TOPAS or the like.

Due to the dehumidification properties of some radiation curable resins, especially hybrid curable liquid radiation curable resins, if the additive manufacturing process is too slow, on the surface of the fluoropolymer, the radiation curable resin may be exposed to the radiation curable resin. Dehumidified before curing. In general, polyolefins are less likely to dewet the resin than fluoropolymers and are therefore preferred depending on the additive manufacturing process. the

Fluoropolymers may also form useful transport layers depending on the process speed of the additive manufacturing process. In an embodiment, the transport layer is a fluoropolymer. In certain embodiments, the transport layer is polytetrafluoroethylene (PTFE). In other embodiments, the transport layer is a copolymer of tetrafluoroethylene and ethylene (ETFE, ). In an embodiment, the transport layer is a fluorinated ethylene propylene copolymer ( FEP). In an embodiment, the transport layer is AF, tetrafluoroethylene and bis(trifluoromethyl)-4,5-difluoro-1,3-dioxole (tetrafluoroethylene and2,2-bis-4,5-difluoro-1,3 -dioxole). In other embodiments, the transport layer is polyvinyl fluoride (PVF), and in other embodiments polyvinylidene fluoride (PVDF).

In an embodiment, the flexible multilayer substrate is isotropic. Isotropy can be achieved with non-oriented or biaxially oriented substrates. In an embodiment, the transport layer is non-oriented. In another embodiment, the transport layer is biaxially oriented (in the x-y plane). In other embodiments, the structural layer is non-oriented, and in embodiments, the structural layer is biaxially oriented. In an embodiment, the isotropic structural layer is formed from a plurality of alignment layers. In an embodiment, the radiation curable resin contacting side of the delivery layer is surface polished, eg, by hand etching the delivery layer with steel wool to create a frosted surface. the

According to a first aspect of the presently claimed utility model, the flexible multilayer substrate comprises a semi-crystalline thermoplastic structural layer. The structural layer has improved physical properties relative to the transport layer. For example, structural layers may provide improved tear resistance, temperature resistance, mechanical properties (eg, tensile strength or yield stress), or other properties. If the additive manufacturing process or device is arranged to transmit actinic radiation through the substrate, the structural layers must also be highly radiation transmissive. the

The structural layer includes a semi-crystalline thermoplastic polymer. In an embodiment, the semicrystalline thermoplastic polymer is polyamide. In other embodiments, the structural layer is polyamide-6, polyamide-6,6, polyamide-4,10, polyamide-4,6, polyamide-11, polyamide-12, polyamide-6T, Polyamide-4T, polylactam and its copolymers. In other embodiments, the structural layer is polyester. In other embodiments, the structural layer is polyethylene terephthalate, polybutylene terephthalate, (polypropyleneterephthalate) or a copolymer of glycolide thereof. In other embodiments, the structural layer is polylactic acid, polyglycolic acid, polyhydroxyalkanoate, polylactone, polyethylene naphthalate (PEN), polybutylene naphthalate (PBN) and the like. copolymer. In other embodiments, the structural layer is polyether. In other embodiments, the structural layer is polyoxymethylene, polyalkylene oxide, and copolymers thereof. In an embodiment, the structural layer is biaxially stretched during processing, thereby creating a biaxial orientation. the

In other embodiments, the structural layer is a reinforced semi-crystalline thermoplastic polymer. The polymer can be reinforced by, for example, fibers or particles. In embodiments, the particles are mineral fillers such as mica, fossil, calcium carbonate, barium sulfate, and the like. In another embodiment, the particles are submicron sized particles, such as nanoclay and nanosilica. Submicron sized particles have the advantage that they can be diffused in a manner that does not substantially affect the light transmission of the substrate. When utilizing reinforcing polymers, the UV transmission of the substrate must be closely monitored, and substantially radiation transparent reinforcing agents are the preferred reinforcing. In an embodiment, the structural layer comprises a polyamide nanocomposite. the

Structural layers of semi-crystalline thermoplastic polymers are employed relative to amorphous materials because semi-crystalline thermoplastic polymers are less brittle and have improved crack resistance compared to amorphous materials. In addition, semi-crystalline thermoplastic polymers have improved resistance to cracking compared to amorphous materials. Cracks are exacerbated by exposure to UV light. In order to provide optimum process conditions in some respects, it is desirable to keep the foil 11 as flat as possible on the contact surface 181 . To this end, the contact surface 181 can be specially designed, for example with suction or clamping means to clamp the foil in lengthwise direction; moreover, mechanical structures can be provided to maintain the length of the foil under a predetermined tension. The optimum tension depends on the type and thickness of the foil, but may typically be around 10N per cm foil width (500N for a 50cm foil width). This tension makes it possible to keep the foil 11 flat on the contact area 181 with the contact height H. FIG. The lengthwise tension is sufficient to keep the foil flat over its entire area, including its edges, and no clamps or other tensioning devices are required on its edges. the

In another embodiment of the invention, there are other types of foils that generally have a lower modulus of elasticity, where the longitudinal tension may not be sufficient to keep the foil flat across the relevant area 181 . At certain edges of the foil 11 there will be a tendency to move up or down or to wrinkle from the desired plane. To this end, the flexible roll arrangement 1 is arranged such that the bending roll 4 bends according to the direction of movement of the foil relative to the carrier table 180 , which significantly reduces any wrinkling at least over the short area defined by the contact surface 181 . the

In this embodiment, the system 100 may include a liquid resin applicator 200 filled with a resin liquid 30 in the example shown. Alternatively, the resin layer may be provided as a prefabricated sheet. In an embodiment, applicator 200 is in the form of one or more knurled rolls. the

Energy source 90 may be arranged to project a pattern through foil 11 when liquid layer 30 is in contact with tangible object 50 at region 51 . In particular, the energy source 90 may be arranged for at least partial curing in at least a part of the cross pattern in the liquid layer. In order to enable light or other radiation from the energy source 90 to cure the liquid layer 30, the foil 11 is preferably substantially transparent to the radiation. the

In the example embodiment shown, energy source 90 is placed on movable foil guiding table 18 between foil guiding elements 19 to expose the layer of uncured material through foil 11 . Alternatively, the energy source is movable relative to the reciprocating foil guide table 180 . the

The movable z-stage 140 is movable in the z-direction before a new layer of curable material is provided to the tangible object 50. Each time a new layer is cured and separated, the carrier plate (z-stage) 150 moves upward together with the tangible object 50 with the cured layer 52 attached thereon. the

The z-direction means the direction outwards from the planar direction of the curable material layer 51 arranged on the foil 11 . The z stage 140 can be raised while the foil guide stage 180 is not moving. In this embodiment, rolling elements 170 enable movement of z-stage 140 . The tangible object 50 is connected to the z-stage 140 and in each method cycle a new layer is laminated from below. Layers of curable material are shown with exaggerated thickness for clarity. the

The foil 11 and the foil guide table 180 are movable independently of each other. In one mode of operation, the foil 11 is moved to place a layer of curable material underneath the tangible object 50 in a first step. At this point, the curable material is not yet in contact with the tangible object 50 . In a second step, foil guide table 180 is moved along tangible object 50 to apply curable material layer 51 to tangible object 50, expose curable material 51 and remove uncured material. In the second step, the foil 11 is substantially not moved relative to the tangible object 50 in the direction perpendicular to z. In order to shorten the length direction of the stage 180, the exposure unit 90 is usually limited to only ² ×2mm elements (‘pixels’, each pixel has LED+microlens) for a working area of about 50 cm along the moving direction of the carrier stage. 6 cm in length and still provide a high resolution of about 15 pixels per mm of working area width. Details of this arrangement are disclosed in PCT/NL2009/050783, which application is hereby incorporated by reference in its entirety.

As used herein, the term "curable material" includes materials that are curable by, for example, UV light, lasers, ionizing radiation (including but not limited to electron beams, gamma rays, or x-rays), or combinations of any of the foregoing, etc. (i.e., curable polymerized and/or crosslinked) any material. The term "curable material" should also be understood to include composite materials of curable and non-curable materials, such as resins mixed with fibers and/or fillers, and the like. the

Partial curing includes curing to the extent that the crossing pattern remains stable upon removal of uncured material from layers other than the crossing pattern. The curable material is not fully cured, but only cured to the extent that the material is sufficiently stable that it is not removed along with the uncured material during the step of removing the uncured material outside the cross pattern. the

A certain exposure time is required to fully cure the cross pattern. Partially curing the cross pattern means curing the pattern to a lesser extent. When the energy source is operated at the same power as that used to complete a full cure, the exposure can be shorter and the speed of the RM and RP processes increased. the

The support arrangement described in the previous embodiments may comprise a single flexible roller. Furthermore, the support arrangement may comprise a plurality of flexible foil guide rollers and a plurality of support systems, in particular: a first flexible foil guide roller and a first support system placed on a first side of the centerline, and a first flexible foil guide roller and a first support system placed on the centerline. Second flexible foil guide rollers on both sides and a second support system. the

The detailed drawings, specific examples, and specific concepts have been presented for purposes of illustration only. While the specific embodiment of the device 100 described and illustrated herein relates to building the model 50 from the top down, the teachings of the present invention can also be applied to devices that build the model upright or at an angle. In the foregoing specification, the invention has been described with reference to specific examples of embodiments of the invention. It will, however, be evident that various modifications and changes can be made without departing from the broader spirit and scope of the invention as set forth in the appended claims. Additionally, objects may be of any suitable size and shape. Furthermore, a device may be physically distributed across multiple devices, yet functionally operate as a single device. Also, devices that functionally form separate devices may be integrated on a single physical device. However, other modifications, variations and substitutions are also possible. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense. Although certain embodiments detail certain optional features as further aspects of the present invention, this description is meant to encompass and specifically disclose all combinations of these features unless otherwise specified or physically impossible. the

Claims (17)

1. An additive manufacturing apparatus comprising a reciprocating foil guiding station (180), said reciprocating foil guiding station comprising: an energy source (90) arranged for at least partially curing at least a portion of the intersecting pattern in a layer of curable material arranged on the foil (11) and in contact with a tangible object; and A foil guiding system on the lead-in side of the contact surface (181) and on the pull-out side of said contact surface (181), said foil guiding system comprising: flexible foil guide rolls (4); and A support system (1) capable of changing and/or reversing the curvature of said flexible foil guiding roll (4) according to the rolling direction (P, Q) of said flexible foil guiding roll (4), and said supporting The system is arranged in contact with said flexible foil guide roller (4), The foil guiding system is used to guide the foil (11) comprising the layer of liquid resin (30) to the contact surface (181) or guide out of the contact surface (181) to contact the tangible object (50), the foil comprising a transport layer and a structural layer, the transport layer comprising polyolefin or fluoropolymer, and the structural layer comprising a semi-crystalline thermoplastic polymers, Wherein the flexible foil guide roller is in contact with the conveying layer of the foil or the structural layer of the foil. the 2. Additive manufacturing apparatus according to claim 1, wherein said foil guiding station comprises a pair of upper and lower foil guiding elements (6, 60), said lower foil guiding element defining a foil height away from said contact surface position (H0), the flexible foil guiding roller (4) is arranged between the pair of upper and lower foil guiding elements to guide the foil to the contact surface (181) or out of the contact Face (181). the 3. Additive manufacturing apparatus according to claim 2, wherein said foil guiding station (180) further comprises an overcoating system (200) for applying said liquid resin layer (30). the 4. Additive manufacturing device according to claim 3, wherein said energy source (90) is placed adjacent to said contact surface (181) to expose a layer of uncured material through said foil (11). the 5. Additive manufacturing apparatus according to claim 4, wherein said energy source (90) comprises a plurality of independently operable LEDs. the 6. The additive manufacturing device according to claim 5, wherein the support system (1) comprises: an end locking element (7) which axially locks said roller (4); a support arrangement (2, 20, 21, 22) defining a support position such that said roller (4) bends at the support joint; and The bearing arrangement (2, 20, 21, 22) is connected to the outer surface (40) of the roller (4) such that the roller (4) is curved between at least two bearing positions (A, B) Way to engage. the 7. The additive manufacturing device according to claim 6, wherein the support system further comprises a locking structure (8, 213) that limits the bending range of the roll bending. the 8. The additive manufacturing device according to claim 7, wherein the locking structure comprises a locking element (213) fixed relative to the support system. the 9. Additive manufacturing device according to claim 8, wherein said support arrangement comprises one or more support elements (20, 21, 22); and said locking structure comprises a connection to at least one of said support elements ( 21) an actuator (8); said actuator (8) is arranged for moving said support element (21) to provide said roller (4) in said two support positions (A, B) Forced bending movement between; said actuator (8) can be controlled in unison with said rolling direction (P, Q). the 10. Additive manufacturing device according to claim 9, wherein said actuator (8) comprises a rotatable arm (80) which moves said at least one said support element (21 ) in said Rotation between two bearing positions (A, B). the 11. Additive manufacturing device according to claim 6, wherein the support arrangement comprises a fixed support surface (2) in bearing contact with the foil guiding roller (4). the 12. The additive manufacturing device according to claim 6, wherein the support arrangement comprises rolling elements (210, 211 ) engaging the guide rollers (4). the 13. Additive manufacturing device according to claim 6, wherein the bearing arrangement defines a bearing contact (21) along a part of the circumference of the roller (4). the 14. The additive manufacturing device of claim 6, wherein the roller surface (40) is adjusted to define a foil drag force defining a roller bending curvature. the 15. The additive manufacturing device of claim 6, wherein the end locking element comprises a roller bearing. the 16. The additive manufacturing device of claim 15, further comprising: measuring means in contact with said foil (11), said measuring means for measuring tension and/or displacement in said foil (11); and a controller in communication with the support system (1) and the measuring device, the controller being capable of adjusting the support system (1) to change the flexible foil guide rollers in response to measurements from the measuring device (4) Curvature. the 17. Additive manufacturing device according to claim 16, wherein the movement of the foil (11) at both ends (A, B) is prevented. the