Apparatus and method for additive manufacturing of products

Abstract

The present invention relates to an apparatus and method for manufacturing products by stereolithography in which the product is both printed and washed, and subsequently post-cured, in an environmentally sealable housing.

Description

[Technical Field]

[0001] The present invention relates to an apparatus and method for producing products according to the principles of additive manufacturing. In particular, the present invention relates to a stereolithography method in which a light source is directed specifically at individual regions of a resin-filled vat (resin vat), thereby selectively curing a photopolymer (hereinafter also referred to as "resin") within the vat. The light used for this purpose, generally ultraviolet light, provides the radicals necessary for polymerization, hardening the resin in the irradiated areas. Typically, this illumination is performed by the printing unit through the locally translucently configured bottom surface of the resin vat, for example by means of a correspondingly controlled LCD matrix. Layers are formed in a liquid resin bath, and the hardened product is then attached to a printing plate which is immersed upside down in the resin bath, and when a layer is completed, the printing plate is lifted slightly to allow the next layer to be applied. This process is also called "printing." Once the printing process is complete, the product can be removed upward from the resin vat. [Background technology]

[0002] Products produced in this manner usually need to be cleaned of any adhering uncured resin residue. For this purpose, it is known to immerse the printed product in a bath of a cleaning agent to clean it of such undesirable constituents.

[0003] Such a device is known from US Pat. No. 5,629,999, in which both the actual printing and the cleaning take place in a common housing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] China Utility Model No. 215550999 Summary of the Invention [Problem to be solved by the invention]

[0005] However, to achieve the desired final strength of the fully cured photopolymer, the printed and washed product often requires a post-cure. For this purpose, the product can be irradiated with suitable light from a post-cure unit, which usually allows this final strength to be achieved within a few minutes. However, post-curing often involves significant costs because the product must first be removed from the printing equipment, placed in a post-cure unit, and then removed again after the post-cure has been fully performed. It should also be noted that photopolymers (resins) used in liquid form are generally classified as health hazards, and contact with human skin, eyes, mucous membranes, etc. should be avoided as much as possible. In this regard, the resin is non-toxic in its cured state. Therefore, it is difficult to handle products that are not completely cured and have liquid resin residues attached. Another problem is that resin residue remains in the cleaning tank during the cleaning process, reducing the effectiveness of the cleaning agent over time.

[0006] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an apparatus for producing products based on the photopolymerization principle that overcomes the above-mentioned disadvantages. [Means for solving the problem]

[0007] This object is achieved by an apparatus according to claim 1 and a method according to claim 11. Further advantageous embodiments are evident from the dependent claims.

[0008] The present invention is based on the principle of photopolymerization of the above type and is based on the recognition that products can be manufactured particularly simply and reliably by using a post-cure unit that is configured to automatically irradiate the printed product with appropriate light after removing it from the resin bath or cleaning bath, thereby subjecting the printed product to complete post-cure. Unlike the prior art, the post-cure unit is an integral component of the machine, and in this way the machine is configured to print, wash and post-cure the product fully automatically, eliminating the need to remove the product before post-cure and feed it to a separate post-cure. This ensures that potentially health-hazardous contact with the photopolymer by operators is prevented, and the post-cure process saves time, simplifies logistics and can be carried out without human intervention either directly after the actual printing (product production) or, if required after printing, following a cleaning process.

[0009] The machines are each configured to simultaneously manufacture one or more products in a repeated process. This process involves the actual printing process, which can produce one or more products attached to the printing plate. The production also includes, if necessary, subsequent cleaning steps and, in each case, post-curing of the printed product in a post-cure unit, after which a new production cycle can be continued. The product thus manufactured can be removed or transported from the apparatus after, for example, post-curing is completed.

[0010] The device according to the invention extends in three mutually orthogonal spatial directions: a vertical height direction Z, a longitudinal direction X and a lateral direction Y. The apparatus includes a production zone where products are produced in layers at a production location. Here, the term "production zone" refers to a spatial portion within the apparatus in which a resin tank containing resin is located during product production (printing process) and in which the product is located during its production.

[0011] Also provided is a holder that is movable in the height direction Z for holding the printing plate. The printing plate serves to hold the product in place during its manufacture. The holder can be moved up and down in a targeted height direction Z relative to the resin vat, thereby keeping the product produced in the resin vat attached to the printing plate and lifting the product layer by layer, allowing the next layer below the previously produced layer to harden.

[0012] Also provided is a printing unit for locally irradiating the resin available in the resin vat with light which acts to locally harden the resin in order to manufacture the product. The apparatus according to the invention further comprises a washing tank for containing a washing agent for washing the product in the resin tank after printing thereof. For this purpose, the printing plate, together with the product adhering to it, can be automatically moved into a washing bath, where a washing agent is applied to the product.

[0013] According to the present invention, compared to the prior art, the device further includes a post-cure unit, which automatically irradiates the product previously removed from the resin tank or cleaning tank with light (post-cure), and this light is suitable for post-curing the structure of the product that is not cured or is incompletely cured. Here, the post-cure unit is provided so that it can direct its light directly onto the product, which is still supported by the printing plate. Most preferably, the post-cure unit is configured to direct light it emits into the production zone to post-cure products located therein. In this case, no additional space is required, since the post-cure is carried out in the production zone according to the invention. The entire device has a compact configuration and can sequentially execute the process steps of "printing," "cleaning," and "post-cure" fully automatically. This solution overturns the widely held preconception in the prior art that post-cure cannot be performed in the same equipment, especially in the production zone, because it is absolutely necessary to avoid unintentionally curing the photopolymer in the resin tank with the light from the post-cure unit. The present invention overcomes this assumption, and if necessary, measures can be taken to prevent this unintended hardening, as will be described below.

[0014] A further embodiment of the present invention relates to a cleaning agent in a cleaning bath. As already mentioned above, after each printing step the printed product has a small amount of uncured resin adhering to it. To wash these away, the printed product is preferably immersed in a cleaning bath filled with a cleaning agent. Isopropanol may be used as the cleaning agent, although those skilled in the art will recognize other suitable cleaning agents. On the other hand, resin residues that build up in cleaning agents reduce their quality and reusability in the long term.

[0015] The inventors of the present invention have now realised that resin residues that accumulate in cleaning baths after the curing process can be particularly easily and effectively removed or filtered out from cleaning agents that are typically liquid. Accordingly, embodiments of the present invention are configured to expose the cleaning agent in the cleaning tank to light that cures resin residue that builds up in the cleaning tank. In particular, for this purpose the light of a post-cure unit is used, which is also used for post-curing the product. This device unit thus performs two functions according to the invention: it post-cures the product and hardens the resin residues in the cleaning agent.

[0016] In a particularly advantageous embodiment of this development, the cleaning bath is arranged in the production zone and thus within the effective range of the post-cure unit, or is at least configured to be automatically movable thereto. Particularly preferably, the washing tank is permanently located within the production zone. During the post-cure treatment of the product by the post-cure unit, its light also reaches the wash tank and cures any resin residue potentially present there, so the post-cure unit and its light perform a dual function and are therefore fully utilized. The irradiation of the product on the one hand and the cleaning bath on the other hand can be carried out either sequentially or overlapping in time, but the above advantages are particularly obtained when the irradiations are carried out simultaneously. The production time can be particularly effectively reduced (including the step of washing off the cleaning agent) since a separate treatment of the cleaning agent for hardening the resin residues adhering to the cleaning agent is no longer necessary.

[0017] The working materials used in the photopolymerization and the cleaning agents used can be hazardous to health. In this regard, in an embodiment of the present invention, the resin tank, together with the cleaning tank and post-cure unit, is arranged in a sealable housing, thereby preventing harmful substances from escaping from the housing into the environment. The housing may be provided with suitable, preferably sealable, openings or connections, for example for removing the finished product (discharge flap) or for supplying working materials such as resins, cleaning agents, etc. In addition, a vent may be provided to exchange the air inside the housing purified by the filter unit with the air surrounding the housing. For maintenance purposes, the housing can be opened, allowing access to the individual components (particularly the resin vat, printing unit, washing vat, and post-cure unit) and the production zone.

[0018] When post-curing a product using the device of the present invention, care must be taken to ensure that the light or scattered light emitted by the post-cure unit does not enter the resin tank containing the resin for printing the product. Otherwise, not only will the post-cure unit post-cure the irradiated product, but the resin in the resin tank will also be partially cured, making it impossible to properly print new products. Therefore, in embodiments of the present invention, a manually or automatically operable protection mechanism is provided to protect the resin vat from incident light that has a curing effect, if desired.

[0019] In the simplest embodiment, the protection mechanism can be configured to cover the resin vat in a light-tight manner, for example by automatically placing a lid on top of the vat. As soon as the lid seals the vessel, the post-cure unit can begin operation. To start a further printing run, the lid must be removed again so that a new printing plate can be moved into the resin bath.

[0020] In an advantageous alternative, instead of using a lid, the resin vat is configured to be moved by a protection mechanism relative to the production zone to a protection zone where it is protected from the incidence of light from the post-cure unit. For example, the apparatus may include a translucent partition wall having an opening therein, which separates the production zone from the protection zone. Here, the protection mechanism is configured to move the resin vat through this opening to one side or the other of the partition wall as desired. To this end, the protection mechanism may include suitable (eg, electromechanical) members, such as one or more drives, spindles, gears, levers, joints, and the like. The partition wall also serves to protect against incident light, and can therefore be considered as part of the protection mechanism. The transfer of the resin bath between the production zone and the protection zone can be set using suitable end positions. Using sensors and associated control devices, reaching the end positions can be evaluated and therefore taken into account in the control process.

[0021] If the resin vat is located in the production zone, the printing process can take place there. After printing is completed (and, if necessary, after cleaning the product by immersing it in a cleaning bath) and before post-cure begins, the protection mechanism can move the resin bath through the opening into the protection zone. Preferably, one side of the resin vat seals the opening in the partition wall (this can also be done in combination with a printing unit, see below). In this case, the resin tank is located in the protective zone and is protected from incident light from the post-cure unit, so that the post-cure unit can operate in the production zone and irradiate light onto the product (and preferably also onto the cleaning tank at the same time).

[0022] The protection mechanism may, for example, comprise a linear drive having a spindle and guide means for moving the resin vat in a straight line. Alternatively, it is conceivable that the resin vat could be moved back and forth between the manufacturing zone and the protection zone by another movement that meets the spatial requirements of the apparatus. This can include one or more pivotal movements, translational movements, or a superposition of these (since protection of the resin vat is achieved by temporarily moving the resin vat away from the effective range of the post-cure unit, movement relative to the production zone theoretically also includes movement of the production zone relative to the stationary resin vat).

[0023] While the focus here is on protecting the resin vat from light in the post-cure unit, advantageous embodiments of the present invention are configured to move the resin vat between the production zone and the protection zone together with the printing unit. There are several reasons for this, one of which is that these two components can only function effectively if they are located in close proximity to each other, and they are dependent on each other in the printing process anyway.

[0024] Further reasons lie in the development of the invention based on further embodiments. Here, the cleaning tank has an upper opening through which the printed product can be lowered into the cleaning tank, thereby washing away excess resin residue. Cleaning agents often contain volatile components that slowly leak out of unsealed cleaning tanks. In addition to the loss of these working materials, there is the possibility of the release of gases or vapors which are harmful to health or flammable, the generation of which must be prevented as far as possible.

[0025] Therefore, in the interaction between the printing unit and the cleaning tank according to the present invention, in an embodiment of the present invention, when the printing unit is placed in the production zone, the printing unit is configured to be used to cover the opening of the cleaning tank to prevent the cleaning agent from leaking out. In particular, it is conceivable that the printing unit (preferably together with the resin bath located directly above it) is placed in the production zone in preparation for the printing process, and at the same time the printing unit uses its bottom surface to seal the cleaning bath located below it. Here, the printing unit forms a generally temporary lid over the open-topped wash tub. This arrangement takes advantage of the situation where the wash tank is not used anyway during the printing process. On the other hand, after the printing process is completed, when the printed product is immersed in the cleaning bath, the resin bath together with the printing unit is no longer needed in the production zone. With regard to the post-cure required after cleaning, as already mentioned above, it is preferable to move the printing unit (especially together with the resin tank) away from the effective area of ​​the post-cure unit in order to prevent undesired hardening of the resin in the resin tank.

[0026] In this manner, embodiments of the present invention are configured such that the resin vat is movable from the manufacturing zone to the protection zone and vice versa, thereby optionally providing its contents for protection from a post-cure unit or for manufacturing products. Furthermore, the printing unit in the production zone can simultaneously perform two tasks: on the one hand, producing products by irradiating the resin in the resin vat with targeted light from below, and on the other hand, covering the wash vat. The resin tank is connected to the printing unit to form a common movable unit (the resin tank is on top and the printing unit is below it in the vertical direction), and by moving this common movable unit back and forth between the manufacturing zone and the protection zone, the above functions can be realized synergistically.

[0027] The protection zone or the production zone may be provided with a filling mechanism for filling the resin vat with resin. There, for example, a storage vessel can be placed, which is provided with a valve that is operable (preferably automatically) to supply fresh resin to the vessel. This can also be done, for example, during washing or post-cure of the product. The storage container may be located outside the housing of the apparatus, with at least one valve nozzle preferably projecting into the interior of the housing through a sealed opening to supply resin to the resin vat. In this case, the storage container can be easily replaced.

[0028] Embodiments of the present invention provide a carrier that is configured to hold a product during several manufacturing or processing steps of the product and, to this end, move the product within the apparatus as needed. Here, the carrier is configured to carry a holder for holding a printing plate with a product attached thereto. The carrier is provided with a linear drive extending in the height direction Z, by which the holder and, together with the holder, the product can be moved up and down. Also, a production position can be defined in the first height region, within which the holder moves upwards during the actual printing process. Preferably, the cleaning tank is located below the manufacturing position when viewed from the height direction Z. After the printing process is completed, the printed product is first completely removed upward in the height direction Z from the resin tank. The resin vat (preferably together with the printing unit) can then be moved in the lateral direction Y from the production zone to the protection zone. This allows the printing unit to open an opening in the cleaning tank and then lower the holder to lower the product in the height direction Z and immerse it in the cleaning agent in the cleaning tank (at the second height region).

[0029] After the cleaning step is completed, the holder together with the product is moved upward in the height direction Z from the cleaning tank to the third height region, where the product can be irradiated with light from the post-cure unit. For the most compact possible configuration, the first height region can be the same as the third height region. In this case, the post-cure unit directs its light towards the production zone where the product was previously printed. However, this does not exclude that light from the post-cure unit can also reach the cleaning tank (preferably located below it) and intentionally cure and filter out any resin residues present there.

[0030] As can be easily understood, this technique allows both printing and cleaning, and the subsequent post-cure, to be performed at positions within the apparatus that differ only in their height position in the Z direction. Using this process and the correspondingly configured equipment, the product does not need to be moved in the longitudinal direction X or the lateral direction Y between the individual processing steps, and the XY coordinates can remain unchanged. This allows the entire device to have a compact configuration.

[0031] Preferably, the carrier is rotatable about a pivot axis extending in the height direction Z. This allows the holder to reach different pivot positions, and in these different pivot positions, different heights can also be reached due to the vertical mobility of the holder. For example, the carrier can be pivoted into a discharge position in the area of ​​the discharge flap, where the printing plate can be automatically decoupled from the holder and can be ejected or removed from the device together with the product. The carrier can then be pivoted to a receiving position in the storehouse where a new printing plate is coupled to the holder and a new product is printed thereon. For this purpose, for example, an automatically actuable magnetic holder is conceivable. The individual pivot positions (storage bin, production zone, discharge flap) are offset from each other by a pivot angle of 90°. Depending on the configuration of the carrier and / or the structural design of the device, other pivot angles may separate the individual positions from one another.

[0032] In an embodiment of the invention, it is also conceivable that the finished product can be automatically decoupled from the printing plate while still in the device and ejected separately from the printing plate, while the printing plate is immediately available for use again. In this case, it is not necessary to prepare and connect new printing plates for each new product or each new printing run. Instead, the same printing plate can be used for successive printing runs. In this case, a printing plate storage within the device can be omitted, resulting in a more compact design of the device. This also reduces the process time.

[0033] Embodiments of the invention may comprise the following features individually or in one or more combinations: a) The printing unit can be positioned above the washing tank as a common unit in the manufacturing zone, together with the resin tank located above it in the vertical direction, so that the printing unit can seal one or more upper openings of the washing tank using its bottom surface while simultaneously manufacturing products hanging from the holder in the resin tank. b) After the printing process has been carried out, the common unit formed by the printing unit and the resin tank can be moved from the production zone to a protection zone protected from light, thereby opening one or more openings in the cleaning tank. c) The holder together with the product adhering to it can be lowered vertically into a washing bath after the printing process for washing (washing). d) After the cleaning has been carried out, the holder together with the product adhering to said holder can be raised again in height and moved from the cleaning bath into the working area of ​​the post-cure unit. e) After the product has been washed, the post-cure unit simultaneously irradiates both the product and the cleaning agent present in the cleaning tank with light, thereby post-curing the product and curing the resin residue present in the cleaning tank, respectively.

[0034] The device according to the invention comprises a control device which is arranged to control the individual components in order to achieve fully automatic control of the manufacturing process. For this purpose, the control device may comprise a processor unit and may further comprise elements for storing data and elements for data exchange (preferably bidirectional) with sensors, output units and further devices for data processing. The control device can be connected to or equipped with an operator terminal, whereby a user can enter or read out programs or respective data, in particular process parameters. Also, optical or acoustic indicator means may be provided and controlled by the control device to indicate normal or error operation of the device. In particular, the exceeding of safety-relevant thresholds can be signalled.

[0035] Since resins have different properties depending on their temperature, for example they are generally easier to process at higher temperatures, in an advantageous embodiment of the invention the resin bath is provided with heating or cooling means so that the resin temperature can be automatically changed as required or maintained at a predetermined level.

[0036] An embodiment of the present invention is equipped with a load cell that allows the weight of the printed product to be recorded and checked (preferably already in process). Preferably, a load cell is positioned between the holder and the printing plate and is connected to a suitable control device so that the current weight of the product can be recorded already during printing and compared with a reference value. In this way, the exact printing progress can be continuously checked for validity, and the printing process can be terminated and / or restarted, for example, prematurely, if a predetermined weight tolerance is exceeded or falls below at a particular printing point.

[0037] Hereinafter, an embodiment of the device according to the present invention will be described in more detail with reference to the drawings. [Brief explanation of the drawings]

[0038] [Figure 1] 1 shows in a schematic perspective view the interior of the device according to the invention immediately after the printing process has been completed; [Figure 2] 2 shows the apparatus of FIG. 1 in preparation for product washing. [Figure 3] 2 shows the apparatus of FIG. 1 during product washing. [Figure 4] 2 shows the apparatus of FIG. 1 during operation of the post-cure unit. [Figure 5] 2 shows the apparatus of FIG. 1 during removal of the finished product. [Figure 6] 2 is a partial view of the apparatus of FIG. 1 with the carrier pivoted; DETAILED DESCRIPTION OF THE INVENTION

[0039] FIG. 1 shows a device V according to the invention in a perspective, partially cutaway view. The housing G, which is substantially rectangular parallelepiped in shape, extends in three mutually orthogonal directions (a longitudinal direction X, a lateral direction Y, and a height direction Z). A cleaning tank A having an upper opening O is disposed approximately in the center of the lower region of the housing G (see, for example, FIG. 2).

[0040] In the manufacturing zone E, a printing unit U is placed above the cleaning tank A, and a resin tank B is placed directly above that. The printing unit U and the resin tank B form a common unit UB, which can automatically move back and forth between a protection zone F and a production zone E in the longitudinal direction X using a protection mechanism M. This protection mechanism M comprises a motor-driven spindle which cooperates with a common unit UB and a guide rod, designated "M" in FIG. 1, which represents further members which the protection mechanism M may be provided with. The manufacturing zone E is separated from the protection zone F by a partition wall W, which includes an opening through which the common unit UB can move using a protection mechanism M.

[0041] In FIG. 1, the common unit UB of the manufacturing zone E is located at a manufacturing position K for manufacturing the product P. A carrier T is arranged adjacent to the common unit UB and the cleaning tank A laterally in the longitudinal direction X, and this carrier T extends in the height direction Z and can automatically rotate around a rotation axis D extending in the height direction Z. The carrier T includes a linear drive, not shown in detail, by means of which an arm protruding laterally from the carrier T and on which the holder H is arranged can be automatically moved up and down in the height direction Z along the carrier T. The holder H serves to hold the printing plate L. On the other hand, the printing plate L serves to receive the product P that is produced in the resin bath B according to the principle of stereolithography.

[0042] For this purpose, the printing plate L can be lowered in a height direction Z by means of a holder H and a carrier T into a resin bath B filled with a photopolymer (resin N). The printing unit U uses light L to locally harden the resin N in the resin tank B. U is configured to irradiate the resin vat B with a target. For this purpose, the bottom of the resin tank B is made translucent in a manner known to those skilled in the art, for example by means of a controllable LCD screen.

[0043] Light L of printing unit U in resin tank B U The resin N hardened by the adhesive adheres to the bottom surface of the printing plate L or to a layer of hardened resin already formed there before. By locally curing the layers and slightly lifting the printing plate after each layer, a multi-layered product P is formed that "hangs" down onto the bottom surface of the printing plate L.

[0044] On the other hand, the printing unit U covers the opening O of the cleaning tank A with its bottom surface, thereby preventing, in particular, volatile components of the detergent S from leaking out of the cleaning tank A.

[0045] After the printing process is completed, the holder H is moved sufficiently upward in the height direction Z using the carrier T, so that the product P hanging down from the printing plate L can be completely removed from the resin tank B. At this stage, the product P is mostly complete, but may have uncured resin residue attached, and at this point, full curing of the product P is usually not yet achieved.

[0046] Therefore, in the next step, preparations are made to wash off the excess resin N adhering to the product P. Figure 2 shows that the common unit UB, which is composed of a resin tank B and a printing unit U, has been moved in the longitudinal direction X from the manufacturing zone E to the protection zone F using the protection mechanism M, and in this state, the resin tank B is protected from incident light from the manufacturing zone E or incident light from the post-cure unit R. Furthermore, the movement of the printing unit U reveals that the opening O of the cleaning tank A is open, and since the opening O opens upward and is accessible, the product P placed on the holder H can be cleaned in the cleaning tank A.

[0047] For this purpose, as shown in Figure 3, the holder H is lowered in the height direction Z from the manufacturing position K by the carrier T until the product P is completely immersed in the cleaning tank A or the cleaning agent S contained therein (lowered state). The cleaning process itself, which removes excess resin N from the product P, can take several seconds or minutes. Optionally, an agitator located within the washing tank can create a current to assist in washing. It is preferable that the holder H or the printing plate L is configured to cover the opening O of the cleaning tank A when in the lowered state in order to prevent the volatile components of the cleaning agent S from leaking out of the cleaning tank A even during cleaning. Ideally, after washing, there is no undesirable resin residue on the product.

[0048] The product P thus cleaned usually still needs to be post-cured to ensure that the resin N and possibly the structure that is not yet fully cured is retained throughout the product. In this regard, as shown in FIG. 4, the holder H together with the printing plate L and the cleaned product P adhering thereto rises again in the height direction Z from the cleaning tank A until the product P enters the effective range of the post-cure unit R. It is preferable to select the coverage area so that the product P is located, for example, at the production location K before which the product P was printed. This allows the entire device to have a compact configuration, and simplifies the positioning control of the holder H using the carrier T.

[0049] The post-cure unit R is configured to irradiate the resin N with light LR suitable for curing the resin N. In particular, the light may be the same type as the light emitted from the printing unit U, and a person skilled in the art will select light having an appropriate wavelength and intensity depending on the type of resin used. Since the product P in the printed state has already reached its final desired shape and no longer requires targeted local irradiation of individual product areas for post-cure, it is sufficient to irradiate the product P more or less diffusely by the post-cure unit R.

[0050] Thus, Figure 4 shows a number of similar LED strips extending in a height direction Z, which together form a post-cure unit R and are configured to irradiate curing light from multiple sides towards the product P. On the other hand, the post-cure unit R is also configured to irradiate the light through the opening O of the cleaning tank A onto the detergent S contained below the product P. As a result, by utilizing the synergistic effect of the present invention, both the product P and the cleaning agent S are irradiated with the curing light of the post-cure unit R, as shown by the dashed line emanating from the post-cure unit R in Figure 4. This not only provides the desired post-cure to the product P, but also (in the illustrated configuration, at the same time) irradiates the curing light onto the resin residues in the cleaning agent S, allowing these residues to be cured (and then removed from the cleaning agent by a filter). This effect is based on the realization that the same light from the post-cure unit R can be used for two functions. For this purpose, it is preferable to arrange the cleaning tank A as close to the post-cure unit R as possible. It is particularly advantageous to choose the cleaning tank A to be arranged below the production position K or production zone E in the height direction Z, as shown. This allows the movement of the product P between the "printing," "cleaning," and "post-cure" processes to be limited to purely vertical movement in the height direction Z, allowing light from the post-cure unit R to reach the cleaning tank A easily and directly. The post-cure step preferably takes only a few minutes.

[0051] When the post-cure by the post-cure unit R is completed, the product P is completed and can be removed from the housing G. For this purpose, as shown in FIG. 5, the holder H can be moved into the area of ​​the ejection flap by automatically pivoting the carrier T and, if necessary, moving it vertically in the height direction Z. In the area of ​​this ejection flap, the printing plate L can be automatically released from the holder by a mechanism not shown in detail, so that it falls together with the product P adhering to it onto an inclined guide plate, where the product can be transported from the inside to the outside of the housing G through a (preferably sealable) opening not shown in detail. To receive a new printing plate L, the holder H of the carrier T can be moved or pivoted about its pivot axis D into a storage area within the housing G, as shown in FIG. In this storage area one or more stacks of further printing plates are placed, the topmost of which can be docked automatically with a holder H. Thereafter, the holder H with the printing plate L can be moved again to the production position K. The common unit UB is also moved from the protection zone F to the production zone E, after which new products can be printed.

[0052] FIG. 1 further shows a resin storage vessel C which serves to (preferably automatically) fill resin vessel B when resin vessel B is located in protection zone F. An air filter JL is also provided to filter the air inside the housing G before it reaches the outside of the container. This filter may serve, for example, to capture harmful or flammable substances released into the housing from the resin N or cleaning agent S. Also provided is a filter JS for the cleaning agent S, which is able to filter out, in particular, hardened resin components or other components from the cleaning agent. For this purpose, the cleaning agent S is preferably guided automatically in circulation through the filter JS. [Explanation of symbols]

[0053] A...Cleaning tank B...Resin tank C···Resin storage container D... Rotation axis E Manufacturing Zone F Protection Zone G···Housing H···Holder K...Manufacturing location J L Air filter J S ···Filter for cleaning agent S L...Print version L U ...printing unit light L R Postcure Unit R light M...protection mechanism N··· resin O Cleaning tank opening P...Product R···Post cure unit S... cleaning agent T... Carrier U Printing unit V...device W···Partition wall UB: A common unit consisting of resin tank B and printing unit U X: Vertical direction Y: Horizontal direction Z: Height direction

Claims

1. An apparatus (V) for additively manufacturing a product (P), a) a production zone (E) in which a product (P) is produced in layers by locally curing a fluid resin (N) that hardens under light irradiation at a production position (K) (printing process); b) a resin tank (B) for containing the resin (N) during the printing process; c) a holder (H) movable in a height direction (Z) for holding a printing plate (L), the height direction (Z), the longitudinal direction (X) and the lateral direction (Y) extending perpendicular to each other, the holder (H) being movable up and down in the height direction (Z) relative to the resin tank (B) with a target set so as to maintain the product (P) produced in the resin tank (B) attached to the printing plate (L); d) applying light (L) to the resin (N) available in the resin tank (B) to locally harden the resin (N) in order to produce the product (P); Ｕ a printing unit (U) for locally irradiating the e) a cleaning tank (A) for containing a cleaning agent (S), in which the printing plate (L) together with the product (P) adhering to the printing plate (L) can be automatically moved into the cleaning tank (A) for applying the cleaning agent (S) to the product (P); f) The device (V) is provided with a post-cure unit (R), and the post-cure unit (R) emits light (L) to post-cure the resin (N). Ｒ ) of the post-cure unit (R) is configured to irradiate the light (L Ｒ ) onto a product (P) attached to the printing plate (L) and previously removed from the resin tank (B), g) Apparatus (V) for additive manufacturing, characterized in that the apparatus (V) is configured to automatically keep the opening (O) of the cleaning tank (A) closed during the printing process by sealing the opening (O) of the cleaning tank (A) with the printing unit (U) to prevent the cleaning agent or its vapor from escaping from the cleaning tank (A).

2. The cleaning tank (A) is disposed in the production zone (E), and thus the light (L) irradiated by the post-cure unit (R) onto the resin component present in the cleaning tank (A) is Ｒ 2. The apparatus for additive manufacturing (V) according to claim 1, characterized in that the cleaning tank (A) is arranged within the effective range of the post-cure unit (R) or is automatically movable into said effective range in order to cure the additive manufacturing by means of a post-cure unit (R).

3. The additive manufacturing apparatus (V) according to claim 1 or claim 2, characterized in that the apparatus (V) is configured to use the post-cure unit (R) to post-cure the product (P) according to claim 1 and harden the resin component in the cleaning tank (A) according to claim 2 sequentially, overlapping in time, or simultaneously.

4. The additive manufacturing apparatus (V) according to any one of claims 1 to 3, characterized in that the resin tank (B), the cleaning tank (A), and the post-cure unit (R) are arranged in a common sealable housing (G), thereby preventing the outflow of harmful substances from the housing (G) into the environment.

5. A protection mechanism (M) that can be operated manually or automatically is provided, and the protection mechanism (M) protects the resin tank (B) from light (L Ｒ 5. The additive manufacturing device (V) according to claim 1, wherein the resin (N) present in the resin tank (B) is protected from irradiation by ultraviolet light (UV) to prevent hardening of the resin (N).

6. The protection mechanism (M) a) configured to cover the resin tank (B) light-tightly, or b) The resin tank (B) is exposed to the light (L) from the post-cure unit (R) with respect to the production zone (E). Ｒ 6. The device (V) for additive manufacturing according to claim 1, wherein the device (V) is configured to move the object to a protected zone (F) protected from the incidence of radiation.

7. The printing unit (U) is movable together with the resin tank (B) from the production zone (E) to the protection zone (F) and then back to the production zone (E), a) The resin tank (B) is configured to prevent light (L) from the post-cure unit (R) in the protection zone (F). Ｒ ) radiation, and / or b) The additive manufacturing apparatus (V) according to any one of claims 1 to 6, characterized in that the printing unit (U) located in the manufacturing zone (E) is configured to cover an opening (O) of the cleaning tank (A) to prevent the outflow of cleaning agent.

8. The apparatus is provided with a carrier (T) for carrying the holder (H), and the carrier (T) a) configured to automatically move the holder (H) in a height direction (Z) through space (X, Y, Z) during the manufacture of the product (P) or for cleaning or post-curing; and / or b) The holder (H) is configured to be rotated between different rotation positions around a rotation axis (D) extending parallel to the height direction (Z), so that depending on the rotation position, i) conveying the printing plate (L) together with the product (P) adhering to said printing plate (L) to an ejection position where said printing plate (L) and / or said product (P) can be ejected from said device (V), or ii) a new printing plate (L) can be received from a printing plate storehouse and a further product (P) can be produced attached to said new printing plate (L), or iii) An apparatus (V) for additive manufacturing according to any one of claims 1 to 7, for producing a new product (P).

9. a) the printing unit (U) can be positioned above the cleaning tank (A) as a common unit (UB) in the production zone (E) together with the resin tank (B) arranged above it in the height direction (Z) so that the printing unit (U) can seal the upper opening (O) of the cleaning tank (A) with its bottom surface while simultaneously producing products (P) hanging from the holder (H) in the resin tank (B); and / or b) After the printing step is completed, the common unit (UB) formed by the printing unit (U) and the resin tank (B) receives light (L Ｒ ) into a protected zone (F) protected from the elements, thereby opening the opening (O) of the cleaning tank (A), and / or c) the holder (H) together with the product (P) attached to the holder (H) can be lowered in the vertical direction (Z) into the washing tank (A) after the printing process for washing (washing); and / or d) the holder (H) together with the product (P) adhering to the holder (H) can be moved upward again in the height direction (Z) after the cleaning is performed from the cleaning tank (A) to the effective area of ​​the post-cure unit (R), and / or e) After the product (P) is washed, the post-cure unit (R) applies light (L) to both the product (P) and the cleaning agent present in the cleaning tank (A). Ｒ 9. The additive manufacturing apparatus (V) according to claim 1, wherein the additive manufacturing apparatus (V) is configured to simultaneously irradiate the first and second light beams from the first and second light beams to the second and third light beams from the first and second ...

10. While the resin tank (B) is located at the production position (K) in the production zone (E), the light (L Ｕ ) to locally harden the resin (N) to produce a product (P) held by the printing plate (L) in the resin tank (B); - Then, the resin tank (B) is automatically covered with a protection mechanism (M) or the resin tank (B) is protected from the light (L) that the post-cure unit (R) irradiates to the production zone (E). Ｒ ) from the post-cure unit (R) to the protective zone (F) which is separated from the manufacturing zone (E) so that the light (L) from the post-cure unit (R) cannot enter the protective zone (F). Ｒ 10. A method for manufacturing a product (P) using the apparatus (V) according to any one of claims 1 to 9, comprising a step of protecting the resin (N) present in the resin tank (B) from any irradiation of radiation.

11. - an automatic cleaning step of the products (P), which comprises moving the printing plates (L) together with the products (P) adhering to the printing plates (L) into a cleaning bath (A), the cleaning bath (A) being arranged in the production zone (E), preferably below the production position (K) in the height direction (Z), and / or - Light (L) from the post-cure unit (R) Ｒ ) and / or a step of automatically post-curing said product (P) by irradiation with - Light (L) from the post-cure unit (R) Ｒ 11. The method for manufacturing according to claim 10, further comprising a step of automatically curing the resin (N) accumulated in the cleaning tank (A) by irradiation with light, preferably simultaneously with or overlapping in time with the post-cure of the product (P) by the post-cure unit (R).

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