Patent Description:
<CIT> relates to a suction mold to produce fiber molded parts with great attention to detail. The invention also relates to a method for producing such a suction mold. According to the invention, this is achieved in that the shape of the fiber molding to be produced is formed by a perforated matrix (suction mold) produced by means of 3D printing or a process associated with rapid prototyping.

<CIT> relates to a molding tool used for molding products of fibrous material manufactured efficiently by employing a lamination molding method. A molding tool having a porous structure used for molding products of fibrous material such as pulp molding is manufactured by a lamination molding method (a method for molding a three-dimensional product by subjecting a material to be laminated to prescribed treatment, the method includes a photosetting resin method). Material lacks are formed on each layer of a laminating material, the layer is laminated one above another, thereby, many suction holes are formed on the molding tool as the material lacks.

Disclosed herein are computer-readable media, methods, and apparatuses that may modify a digital model of a feature that is to be incorporated into a digital model of screen that is to be used to generate a wet part, such as a molded fiber article. The digital model of the feature may be modified to include a plurality of pores at determined locations in the digital model of the feature. The feature may correspond to an embossed detail, such as an embossed graphical element, an embossed logo, an embossed text, a predefined embossed texture, a predefined embossed pattern, a bas relief, a combination thereof, or the like. A processor may process the digital model of a screen separately from the digital model of the feature. That is, for instance, the locations of pores in the digital model of the feature may be determined in the digital model of the screen prior to the addition of the digital model of the feature to the digital model of the screen. The pores may also be added at the determined locations in the digital model of the screen prior to addition of the digital model of the feature to the digital model of the screen.

As discussed herein, the screen may be implemented in a formation of a wet part from a slurry of a liquid and material elements. In addition, the screen may be a forming screen or a transfer screen.

Through implementation of the features of the present disclosure, a processor may determine the locations of the pores in the digital model of the screen prior to the addition of the digital model of the feature to the digital model of the screen. The pores in the digital model of the screen may also be added at the determined locations in the digital model of the screen prior to addition of the digital model of the feature to the digital model of the screen. In one regard, this may make the determination and placement of the pores in the digital model of the screen relatively simpler and less computationally intensive because the digital model of the screen may include relatively flat surfaces whereas the digital model of the feature may include raised, curved, textured, patterned, and/or the like surfaces. That is, the processor may place the pores at normals to the surface of the digital model of the screen, e.g., perpendicularly to the locations at the surface at which the pores are to be placed, which may be simpler and may result in more accurately placed pores in the screen. By placing the pores perpendicularly to the surface at which the pores are placed, the pores may be placed without causing, for instance, some of the pores to intersect each other, the pores having noisy orientations, and the like. Intersecting pores may be undesirable because they may result in violations of minimum pore distance constraints, which may lead to the formation of weak points in the screen.

Reference is first made to <FIG>, <FIG>, and <FIG>. <FIG> shows a block diagram of an example computer-readable medium <NUM> that may have stored thereon computer-readable instructions for modifying a digital model <NUM> of a feature <NUM> to include a plurality of pores <NUM> at determined locations in the digital model <NUM> of the feature <NUM>. <FIG> shows a diagram <NUM>, which includes an example processor <NUM> that may execute the computer-readable instructions stored on the example computer-readable medium <NUM> on the digital model <NUM> of the feature <NUM> to generate a modified digital model <NUM> of the feature <NUM>. <FIG>, respectively, depict, cross-sectional side views of an example forming tool <NUM> and an example transfer tool <NUM> and <FIG> shows a cross-sectional side view of the example forming tool <NUM> and the example transfer tool <NUM> during a removal by the transfer tool <NUM> of the wet part <NUM> from the forming tool <NUM>. It should be understood that the example computer-readable medium <NUM> depicted in <FIG>, the example processor <NUM> depicted in <FIG>, and/or the example forming tool <NUM> and the example transfer tool <NUM> respectively depicted in <FIG> may include additional attributes and that some of the attributes described herein may be removed and/or modified without departing from the scopes of the example computer-readable medium <NUM>, the example processor <NUM>, and/or the example forming tool <NUM> and the example transfer tool <NUM>.

The computer-readable medium <NUM> may have stored thereon computer-readable instructions <NUM>-<NUM> that a processor, such as the processor <NUM> depicted in <FIG>, may execute. The computer-readable medium <NUM> may be an electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. The computer-readable medium <NUM> may be, for example, Random Access memory (RAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a storage device, an optical disc, and the like. Generally speaking, the computer-readable medium <NUM> may be a non-transitory computer-readable medium, in which the term "non-transitory" does not encompass transitory propagating signals.

The processor <NUM> may fetch, decode, and execute the instructions <NUM> to obtain a digital model <NUM> of a screen <NUM> to be fabricated by a three-dimensional (3D) fabrication system <NUM>. The digital model <NUM> of the screen <NUM> may include either a plurality of pores <NUM> or the digital model <NUM> of the screen <NUM> is to be processed to algorithmically add a plurality of pores <NUM> to the digital model <NUM>. As discussed herein, the screen <NUM> is to be implemented in a formation of a wet part <NUM> from a slurry <NUM> of a liquid and material elements. In some examples, the screen <NUM> may be a forming screen <NUM> of a forming tool <NUM> as shown in <FIG>. In other examples, the screen <NUM> may be a transfer screen <NUM> of a transfer tool <NUM>. The forming tool <NUM> and the transfer tool <NUM> are described in greater detail herein.

The processor <NUM> may fetch, decode, and execute the instructions <NUM> to obtain a digital model <NUM> of a feature <NUM> to be added to a portion of the screen <NUM>. As shown in <FIG>, the feature <NUM> may be a structure that may be added to a surface of the screen <NUM> or may include a shape that may be removed from the screen <NUM> to impart a detail <NUM> corresponding to the feature <NUM> onto the wet part <NUM> during formation of the wet part <NUM>. In either case, the feature <NUM> may be an embossed graphical element, an embossed logo, text, a predefined embossed texture, a predefined embossed pattern, a bas relief, a combination thereof, or the like. The feature <NUM> may be embossed as a positive, a negative, or a combination of both, relief.

Each of the digital models <NUM> and <NUM> may be a 3D computer model of a respective one of the screen <NUM> and the feature <NUM>, such as a computer aided design (CAD) file, or other digital representation of these components. In addition, the processor <NUM> may obtain (or equivalently, access, receive, or the like) the digital models <NUM>, <NUM> from a data store (not shown) or some other suitable source. In some examples, the digital models <NUM>, <NUM> may be generated using a CAD program or another suitable design program.

According to examples, and as discussed in greater detail herein, the forming tool <NUM> and the transfer tool <NUM> may be employed in the fabrication of a wet part <NUM> from a slurry <NUM> of a liquid and material elements. In some examples, the liquid may be water or another type of suitable liquid in which pulp material, e.g., paper, wood, fiber crops, bamboo, or the like, may be mixed into the slurry <NUM>. The material elements may be, for instance, fibers of the pulp material. The wet part <NUM> may thus be formed of molded fiber.

The processor <NUM> may fetch, decode, and execute the instructions <NUM> to incorporate the digital model <NUM> of the feature <NUM> with the digital model <NUM> of the screen <NUM>. In some examples, the processor <NUM> may incorporate the digital model <NUM> of the feature <NUM> by adding the digital model <NUM> of the feature <NUM> onto a surface of the digital model <NUM> of the screen <NUM> to cause the digital model <NUM> of the feature <NUM> to extend above the surface of the digital model <NUM> of the screen <NUM>, in which the feature <NUM> is to be added to the screen <NUM> when the screen <NUM> and the feature <NUM> are fabricated. In other examples, the processor <NUM> may incorporate the digital model <NUM> of the feature <NUM> by adding the digital model <NUM> of the feature <NUM> below a surface of the digital model <NUM> of the screen <NUM> to cause the digital model <NUM> of the feature <NUM> to extend below the surface of the digital model <NUM> of the screen <NUM>, in which the feature <NUM> is to be removed from the screen <NUM> when the screen <NUM> is fabricated. Examples of both types of features <NUM> are depicted in <FIG>. The features <NUM> may be sections (e.g., protrusions) that may be raised above a nominal surface of the screen digital model <NUM>, sections (e.g., indentations) that may be below the nominal surface of the screen digital model <NUM>, and/or a combination thereof.

The processor <NUM> may fetch, decode, and execute the instructions <NUM> to identify locations in the digital model <NUM> of the feature <NUM> that are in line with pores <NUM> in the digital model <NUM> of the screen <NUM>. That is, the processor <NUM> may identify the locations of the pores <NUM> in the digital model <NUM> of the screen <NUM> and the locations in the digital model <NUM> of the feature <NUM> at which the pores <NUM> intersect with the feature <NUM>. The intersecting locations in the digital model <NUM> of the feature <NUM> may be equivalent to the locations that are in line with the pores <NUM> in the digital model <NUM> of the screen <NUM>.

According to examples, the pores <NUM> may have previously been positioned in the digital model <NUM> of the screen <NUM>. In other examples, the processor <NUM> may process the digital model <NUM> of the screen <NUM> to algorithmically add the plurality of pores <NUM> to the digital model <NUM> of the screen <NUM>. For instance, the processor <NUM> may employ packing operations to determine the locations at which the pores <NUM> are to be placed in the screen <NUM>. By way of example, the processor <NUM> may implement a packing algorithm that may cause a maximum number of pores <NUM> to be added to the screen <NUM> while causing the screen <NUM> to have a certain level of mechanical strength, e.g., to prevent weak points. In this example, the algorithm may be a sphere or ellipsoid packing algorithm or other suitable algorithm for determining placements of the pores <NUM>.

In examples in which the screen <NUM> is a transfer screen <NUM>, the processor <NUM> may determine the locations at which the pores <NUM> of the transfer screen <NUM> are to be positioned in the transfer screen <NUM> to allow liquid to be suctioned from the wet part <NUM> when the transfer screen <NUM> is mounted to the transfer mold <NUM> and a vacuum pressure is applied to the transfer mold <NUM>. The processor <NUM> may determine the pore <NUM> locations that may cause, for instance, substantially even application of pressure across the transfer screen <NUM> through testing of previously fabricated transfer screens <NUM> and transfer molds <NUM>, through modeling of transfer screens <NUM> having various properties, and/or the like.

In examples in which the screen <NUM> is a forming screen <NUM>, the processor <NUM> may determine the locations at which the pores <NUM> of the forming screen <NUM> are to be positioned in the forming screen <NUM> to allow liquid to be suctioned from the slurry <NUM> to form the wet part <NUM> on the forming screen <NUM> when the forming screen <NUM> is mounted to the forming mold <NUM> and a vacuum pressure is applied to the forming mold <NUM>. The processor <NUM> may determine the pore <NUM> locations that may cause, for instance, substantially even application of pressure across the forming screen <NUM> through testing of previously fabricated forming screens <NUM> and forming molds <NUM>, through modeling of forming screens <NUM> having various properties, and/or the like.

The processor <NUM> may fetch, decode, and execute the instructions <NUM> to modify the digital model <NUM> of the feature <NUM> to add pores <NUM> at the identified locations in the digital model <NUM> of the feature <NUM> to extend the pores <NUM> in the digital model <NUM> of the screen <NUM> through the digital model <NUM> of the feature <NUM>. As a result, vacuum pressure may be applied through the pores <NUM> in the screen <NUM> and the pores <NUM> in the feature <NUM>. In instances in which the feature <NUM> is to add an indentation into the screen <NUM>, the processor <NUM> may modify the digital model <NUM> of the feature <NUM> by causing the pores <NUM> to extend into the feature <NUM>.

In some examples, the processor may generate a modified screen digital model <NUM> that may include the modified feature digital model <NUM>. In addition, the processor <NUM> may send the modified screen digital model <NUM> to the 3D fabrication system <NUM>, in which the 3D fabrication system <NUM> is to fabricate the screen <NUM> with the feature <NUM> and the plurality of pores <NUM>, <NUM> at the determined placements. Particularly, the processor <NUM> may send the modified screen digital model <NUM>, which may include the modified feature digital model <NUM>, to a controller or processor of the 3D fabrication system <NUM>, which may process or otherwise use the modified screen digital model <NUM> to fabricate the screen <NUM>. In other examples, the processor <NUM> may be the controller or processor of the 3D fabrication system <NUM>.

The 3D fabrication system <NUM> may be any suitable type of additive manufacturing system. Examples of suitable additive manufacturing systems may include systems that may employ curable binder jetting onto build materials (e.g., thermally or UV curable binders), ink jetting onto build materials, selective laser sintering, stereolithography, fused deposition modeling, etc. In a particular example, the 3D fabrication system <NUM> may form the transfer screen <NUM> by binding and/or fusing build material particles together. In any of these examples, the build material particles may be any suitable type of material that may be employed in 3D fabrication processes, such as, a metal, a plastic, a nylon, a ceramic, an alloy, and/or the like. Generally speaking, higher functionality/performance transfer screens <NUM> may be those with the smallest pore size to block fibers of smaller sizes, and hence some 3D fabrication system technologies may be more suited for generating the transfer screens <NUM> than others.

As discussed herein, the processor <NUM> may process the digital model <NUM> of the screen <NUM> separately from the digital model <NUM> of the feature <NUM>. That is, for instance, the locations of the pores <NUM> may be determined in the digital model <NUM> of the screen <NUM> prior to the addition of the digital model <NUM> of the feature <NUM> to the digital model <NUM> of the screen <NUM>. The pores <NUM> may also be added at the determined locations in the digital model <NUM> of the screen <NUM> prior to addition of the digital model <NUM> of the feature <NUM> to the digital model <NUM> of the screen <NUM>. In one regard, this may make the determination and placement of the pores <NUM> relatively simpler and less computationally intensive because the digital model <NUM> of the screen <NUM> may include relatively flat surfaces whereas the digital model <NUM> of the feature <NUM> may include raised, curved, textured, patterned, and/or the like surfaces. That is, the processor <NUM> may place the pores <NUM> at normals to the surface of the digital model <NUM> of the screen <NUM>, which may be simpler and may result in more accurately placed pores <NUM> in the screen <NUM>, e.g., perpendicularly to the locations at the surface at which the pores are to be placed. By placing the pores <NUM> perpendicularly to the surface at which the pores <NUM> are placed, the pores <NUM> may be placed without causing, for instance, some of the pores <NUM> to intersect each other. Intersecting pores <NUM> may be undesirable because they may result in violations of minimum pore distance constraints.

Additionally, the processor <NUM> may determine the locations of the pores <NUM> in the digital model <NUM> of the feature <NUM> after the pores <NUM> have been added to the digital model <NUM> of the screen <NUM>. In one regard, by determining the locations of the pores <NUM> separately from the determination of the locations of the pores <NUM> in the digital model <NUM> of the screen <NUM>, the processor <NUM> may accurately determine the locations of the pores <NUM> such that air and/or liquid may freely flow through the pores <NUM>, <NUM>.

In particular examples, the digital model <NUM> of the screen <NUM> may include a substantially horizontally extending surface and a substantially vertically extending surface. In these examples, the processor <NUM> may incorporate the digital model <NUM> of the feature <NUM> to the substantially horizontally extending surface, the substantially vertically extending surface, or both the substantially horizontally extending surface and the substantially vertically extending surface.

In some examples, the processor <NUM> may be part of an apparatus <NUM>, which may be a computing system such as a server, a laptop computer, a tablet computer, a desktop computer, or the like. The processor <NUM> may be a semiconductor-based microprocessor, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), and/or other suitable hardware device. The apparatus <NUM> may also include a memory that may have stored thereon computer-readable instructions (which may also be termed computer-readable instructions) that the processor <NUM> may execute. The memory may be an electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. The memory may be, for example, Random Access memory (RAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a storage device, an optical disc, and the like. The memory, which may also be referred to as a computer-readable storage medium, may be a non-transitory computer-readable storage medium, where the term "non-transitory" does not encompass transitory propagating signals.

Reference is now made to <FIG>. <FIG> shows a cross-sectional side view of a forming tool <NUM>, in which a portion of the forming tool <NUM> has been depicted as being placed within a volume of the slurry <NUM>. <FIG> shows a cross-sectional side view of the transfer tool <NUM> that may remove the wet part <NUM> from the forming screen <NUM>. <FIG> shows a cross-sectional side view of the forming tool <NUM> and the transfer tool <NUM> during a removal by the transfer tool <NUM> of the wet part <NUM> from the forming tool <NUM>. The forming tool <NUM> and the transfer tool <NUM> may collectively form a pulp molding tool set.

As shown in <FIG>, the forming tool <NUM> may include a forming mold <NUM> and a forming screen <NUM>, in which the forming screen <NUM> may overlay the forming mold <NUM>. As shown in <FIG>, the transfer tool <NUM> may include a transfer mold <NUM> and a transfer screen <NUM>. As discussed herein, either or both of the forming screen <NUM> and the transfer screen <NUM> may be equivalent to the screen <NUM> depicted in <FIG>. In some examples, the forming screen <NUM> and the transfer screen <NUM> may be fabricated by a 3D fabrication system <NUM>. The forming mold <NUM> and the transfer screen <NUM> may also be fabricated by the 3D fabrication system <NUM>. In some examples, however, the transfer tool <NUM> may not include the transfer screen <NUM>. The fabricated forming screen <NUM> and the fabricated transfer screen may be used to form we parts <NUM>, e.g., molded fiber articles.

In some examples, the forming mold <NUM> and/or the transfer mold <NUM> may be removably mounted onto respective supporting structures (not shown) such that, for instance, the forming mold <NUM> may be moved independently from the transfer mold <NUM>. Moreover, the forming mold <NUM> and the forming screen <NUM> may be fabricated to have shapes to which the wet part <NUM> may be molded when formed on the forming screen <NUM>. Likewise, the transfer mold <NUM> and the transfer screen <NUM> may be fabricated to have shapes that may engage multiple surfaces of the wet part <NUM> formed on the forming screen <NUM>. The transfer screen <NUM> may have a shape that is complementary to the shape of the forming screen <NUM>.

As shown, the forming mold <NUM> may be formed to have a relatively larger thickness than the forming screen <NUM> and the transfer mold <NUM> may be formed to have a relatively larger thickness than the transfer screen <NUM>. In some examples, the transfer screen <NUM> and the forming screen <NUM> may have the same or similar thicknesses and/or the transfer mold <NUM> and the forming mold <NUM> may have the same or similar thicknesses. The larger thicknesses of the forming mold <NUM> and the transfer mold <NUM> may cause the forming mold <NUM> and the transfer mold <NUM> to be substantially more rigid than the forming screen <NUM> and the transfer screen <NUM>. The forming mold <NUM> may provide structural support for the forming screen <NUM> and the transfer mold <NUM> may provide structural support for the transfer screen <NUM>.

In some examples, different versions of the forming screen <NUM> may be mounted to the forming mold <NUM> to form wet parts <NUM> having different details. For instance, a first forming screen <NUM> may include a first feature <NUM> that may be imprinted onto the wet part <NUM> as a first detail <NUM> and a second forming screen <NUM> may include a second feature <NUM> that may be imprinted onto the wet part <NUM> as a second detail <NUM>, in which the first feature <NUM> and the second feature <NUM> may correspond to embossed logos, predefined embossed textures, embossed text, embossed designs, and/or the like. In this regard, different embossed details <NUM> may be added to the wet part <NUM> through the use of different forming screens <NUM>, while using the same forming mold <NUM>, which may simplify the formation of wet parts <NUM> having various details <NUM>.

Likewise, different versions of the transfer screen <NUM> may be mounted to the transfer mold <NUM> to imprint different details <NUM> onto a surface (or multiple surfaces) of the wet parts <NUM>. For instance, a first transfer screen <NUM> may include a first feature <NUM> that may be imprinted onto the wet part <NUM> as a first detail <NUM> and a second forming screen <NUM> may include a second feature <NUM> that may be imprinted onto the wet part <NUM> as a second detail <NUM>. The first detail <NUM> and the second detail <NUM> may also include embossed logos, predefined embossed textures, predefined embossed patterns, embossed text, embossed designs, and/or the like. In this regard, different details may be added to the wet part <NUM> through the use of different transfer screens <NUM>, while using the same transfer mold <NUM>, which may also simplify the formation of wet parts <NUM> having various details <NUM>. In some examples, the features <NUM> on the transfer screen <NUM> may be complementary versions of features <NUM> on the forming screen <NUM> such that, for instance, a common detail <NUM> may be formed on both opposite surfaces on the wet part <NUM>.

The forming mold <NUM> and/or the forming screen <NUM> may include an attachment mechanism (or attachment device) for the forming screen <NUM> to be mounted to the forming mold <NUM>. Likewise, the transfer mold <NUM> and/or the transfer screen <NUM> may include an attachment mechanism (or attachment device) for the transfer screen <NUM> to be mounted to the transfer mold <NUM>. In either case, the mechanism may include mechanical fasteners, detents, and/or the like to enable the forming screen <NUM> to be removably mounted onto the forming mold <NUM> and/or the transfer screen <NUM> to be removably mounted onto the transfer mold <NUM>. The mechanism that mounts the forming screen <NUM> to the forming mold <NUM> and/or that mounts the transfer screen <NUM> to the transfer mold <NUM> may be a quick release mechanism to enable the forming screen <NUM> and/or the transfer screen <NUM> to easily be released from the respective forming mold <NUM> and transfer mold <NUM>. This may facilitate replacement of the forming screen <NUM> and/or the transfer screen <NUM> for maintenance purposes and/or for screens <NUM>, <NUM> having different features to be employed in the formation of wet parts <NUM>.

As also shown in <FIG>, each of the forming mold <NUM>, the forming screen <NUM>, the transfer mold <NUM>, and the transfer screen <NUM> may include respective pores <NUM>, <NUM>, <NUM>, <NUM> that may extend completely through respective top and bottom surfaces of the forming mold <NUM>, the forming screen <NUM>, the transfer mold <NUM>, and the transfer screen <NUM>. The pores <NUM>, <NUM> respectively in the forming screen <NUM> and the transfer screen may be significantly smaller than the pores <NUM>, <NUM> respectively in the forming mold <NUM> and the transfer mold <NUM>. In addition, a plurality of structural features, such as pillars <NUM> (shown in <FIG>) may be provided between the surfaces of the forming mold <NUM> and the forming screen <NUM> and between the transfer mold <NUM> and the transfer screen <NUM> that are respectively adjacent and face each other to enable liquid to flow laterally between the forming mold <NUM> and the forming screen <NUM> and between the transfer mold <NUM> and the transfer screen <NUM>. As some of the pores <NUM> in the forming screen <NUM> may not directly align with the pores <NUM> in the forming mold <NUM> and some of the pores <NUM> in the transfer screen <NUM> does not directly align with the pores <NUM> in the transfer mold <NUM>, the channels <NUM> formed by the structural features may enable liquid to flow through those pores <NUM>, <NUM> in addition to the pores <NUM>, <NUM> that are directly aligned with respective the pores <NUM>, <NUM>.

Although not shown, the forming tool <NUM> may be in communication with a plenum to which a vacuum source may be connected such that the vacuum source may apply a vacuum pressure through the pores <NUM>, <NUM> in the forming mold <NUM> and the forming screen <NUM>. When the vacuum pressure is applied through the pores <NUM>, <NUM>, some of the liquid in the slurry <NUM> may be suctioned through the pores <NUM>, <NUM> and may flow into the plenum as denoted by the arrows <NUM>. As the liquid flows through the pores <NUM>, <NUM>, the forming screen <NUM> may prevent the material elements in the slurry <NUM> from flowing through the pores <NUM>. That is, the pores <NUM> may have sufficiently small dimensions, e.g., diameters or widths, that may enable the liquid to flow through the pores <NUM> while blocking the material elements from flowing through the pores <NUM>. In one regard, the diameters or widths of the pores <NUM> may be sized based on sizes of the material elements, e.g., fibers, in the slurry <NUM>. By way of particular example, the pores <NUM> may have diameters of around <NUM>. However, in some instances, the pores <NUM> may have irregular shapes as may occur during 3D fabrication processes.

Over a period of time, which may be a relatively short period of time, e.g., about a few seconds, less than about a minute, less than about five minutes, or the like, the material elements may build up on the forming screen <NUM>. Particularly, the material elements in the slurry <NUM> may be accumulated and compressed onto the forming screen <NUM> into the wet part <NUM>. The wet part <NUM> may take the shape of the forming screen <NUM>. In addition, the thickness and density of the wet part <NUM> may be affected by the types and/or sizes of the material elements in the slurry <NUM>, the length of time that the vacuum pressure is applied while the forming mold <NUM> and the forming screen <NUM> are placed within the volume of the slurry <NUM>, etc. That is, for instance, the longer that the vacuum pressure is applied while the forming mold <NUM> and the forming screen <NUM> are partially immersed in the slurry <NUM>, the wet part <NUM> may be formed to have a greater thickness.

After a predefined period of time, e.g., after the wet part <NUM> having desired properties has been formed on the forming screen <NUM>, the forming mold <NUM> and the forming screen <NUM> may be removed from the volume of slurry <NUM>. For instance, the forming mold <NUM> may be mounted to a movable mechanism that may move away from the volume of slurry <NUM>. In some examples, the movable mechanism may rotate with respect to the volume such that rotation of the movable mechanism may cause the forming mold <NUM> and the forming screen <NUM> to be removed from the volume of slurry <NUM>. In other examples, the movable mechanism may be moved laterally with respect to the volume of slurry <NUM>. As the forming mold <NUM> and the forming screen <NUM> are removed from the volume, some of the excess slurry <NUM> may come off of the wet part <NUM>. However, the wet part <NUM> may have a relatively high concentration of liquid.

Following the formation of the wet part <NUM> on the forming screen <NUM> and movement of the forming screen <NUM> and the wet part <NUM> out of the volume of slurry <NUM>, the transfer tool <NUM> may be moved such that the transfer screen <NUM> may contact the wet part <NUM> on the forming screen <NUM>. That is, for instance, the transfer mold <NUM> may be attached to a movable mechanism (not shown), in which the movable mechanism may cause the transfer mold <NUM> and the transfer screen <NUM> to move toward the forming screen <NUM>. In some examples, the transfer tool <NUM> may be moved to cause the transfer screen <NUM> to be in contact with the wet part <NUM> prior to the wet part <NUM> being de-watered while on the forming screen <NUM>, e.g., within a few seconds of the wet part <NUM> being removed from the volume of slurry <NUM>. In one regard, the transfer tool <NUM> may engage the wet part <NUM> relatively quickly after formation of the wet part <NUM>, which may enable the transfer tool <NUM> to remove the wet part <NUM> relatively quickly and the forming tool <NUM> to be inserted into the volume of slurry <NUM> to form a next wet part <NUM>.

In addition, the transfer tool <NUM> may be in communication with a plenum to which a vacuum source may connected such that the vacuum source may apply a vacuum pressure through the pores <NUM>, <NUM> while the wet part <NUM> is in contact with the transfer screen <NUM>. The vacuum source may be the same or a different vacuum source to which the forming tool <NUM> may be in communication. The vacuum pressure applied through the forming tool <NUM> may be terminated or reversed (e.g., applied in the opposite direction) while the vacuum pressure is applied through the transfer tool <NUM>.

<FIG> shows a state in which the transfer tool <NUM> may be in the process of removing the wet part <NUM> from the forming screen <NUM>. Particularly, in that figure, the transfer screen <NUM> has been moved into contact with the wet part <NUM> and a vacuum pressure has been applied onto the wet part <NUM> through the transfer screen <NUM>. In addition, while the vacuum pressure is applied onto the wet part <NUM>, the transfer tool <NUM> may be moved away from the forming tool <NUM> (or the forming tool <NUM> may be moved away from the transfer tool <NUM>) to pull the wet part <NUM> off of the forming screen <NUM>. To further facilitate removal of the wet part <NUM> from the forming screen <NUM>, air pressure may be applied through the forming tool <NUM> as denoted by the arrows <NUM>. As such, the wet part <NUM> may be biased toward the transfer tool <NUM> as opposed to being biased toward the forming tool <NUM>. While the wet part <NUM> is biased toward the transfer tool <NUM>, the transfer tool <NUM> may be moved away from the forming tool <NUM> such that the transfer tool <NUM> may remove the wet part <NUM> from the forming tool <NUM>. In <FIG>, the forming tool <NUM> and the transfer tool <NUM> have been rotated <NUM>° from their respective positions in <FIG>. It should, however, be understood that the transfer mold <NUM> may remove the wet part <NUM> from the forming screen <NUM> while the forming tool <NUM> and the transfer tool <NUM> are in other orientations.

As shown in <FIG>, the transfer screen <NUM> may include pores <NUM> across multiple surfaces of the transfer screen <NUM>. In some examples, the pores <NUM> may be positioned deterministically in the transfer screen <NUM> to cause pressure to be applied substantially evenly across the transfer screen <NUM> when the vacuum pressure is applied. As a result, pressure may be applied substantially evenly across the surface of the wet part <NUM> that is in contact with the transfer screen <NUM>. This may prevent the application of increased pressure at a particular location on the surface of the wet part <NUM>, which may prevent the wet part <NUM> from being damaged by the application of the pressure onto the wet part <NUM> through the transfer screen <NUM>. Additionally, this may enable the transfer tool <NUM> to remove wet parts <NUM> having a vertically or substantially vertically extending (e.g., zero draft) surface (or surfaces) from the forming screen <NUM> as the pressure may be sufficient to overcome frictional and other forces applied by the forming screen <NUM> onto the wet part <NUM>.

When the wet part <NUM> is in contact with the transfer screen <NUM>, the wet part <NUM> may include some of the liquid from the slurry <NUM>. In addition, when the vacuum pressure is applied through the pores <NUM>, <NUM>, some of the liquid in the wet part <NUM> may be suctioned through the pores <NUM>, <NUM> and may flow into the plenum as denoted by the arrows <NUM>. As the liquid flows through the pores <NUM>, <NUM>, the transfer screen <NUM> may prevent the material elements in the wet part <NUM> from flowing through the pores <NUM>. That is, the pores <NUM> may have sufficiently small dimensions, e.g., diameters or widths, that may enable the liquid to flow through the pores <NUM> while blocking the material elements from flowing through the pores <NUM>. In one regard, the diameters or widths of the pores <NUM> may be sized based on sizes of the material elements, e.g., fibers, in the slurry <NUM>. By way of particular example, the pores <NUM> may have diameters of around <NUM> or smaller. However, in some instances, the pores <NUM> may have irregular shapes as may occur during 3D fabrication processes.

In one regard, the application of the vacuum pressure through the pores <NUM>, <NUM> may de-water the wet part <NUM> by removing some of the liquid from the wet part <NUM>. As a result, when the wet part <NUM> undergoes drying, for instance, in an oven, the amount of energy and/or the amount of time to dry the wet part <NUM> may significantly be reduced.

In another regard, the application of vacuum pressure through the pores <NUM>, <NUM> may cause the material elements at the surface of the wet part <NUM> that is contact with the transfer screen <NUM> to have a greater density than the material elements closer to the center of the wet part <NUM>. As a result, the wet part <NUM> may resist warpage during drying of the wet part <NUM>, for instance, in an oven, due to a greater level of symmetrical shrinkage afforded by the denser surface matching the similarly dense surface on the forming screen <NUM> side of the wet part <NUM>. Additionally, the surface may be relatively smoother than when the wet part <NUM> is allowed to de-water without the application of pressure onto the surface of the wet part <NUM>.

As the liquid flows through the pores <NUM>, <NUM>, the material elements in the wet part <NUM> may be prevented from flowing through the pores <NUM> in the transfer screen <NUM>. That is, the pores <NUM> may have sufficiently small dimensions, e.g., diameters or widths, that may enable the liquid to flow through the pores <NUM> while blocking the material elements from flowing through the pores <NUM>. In one regard, the diameters or widths of the pores <NUM> may be sized based on sizes of the material elements, e.g., fibers, in the slurry <NUM>.

According to examples, the pores <NUM>, <NUM> may respectively be positioned in the forming mold <NUM> and the forming screen <NUM> and may have properties, e.g., sizes and/or shapes, such that the wet part <NUM> may be formed with predefined characteristics. For instance, the pores <NUM>, <NUM> may be positioned and may have certain properties to cause the wet part <NUM> to be formed to have an intended thickness (or thicknesses) throughout the wet part <NUM>. By way of particular example, the pores <NUM>, <NUM> may be positioned and may have certain properties to cause thicknesses of the wet part <NUM> to be consistent throughout the wet part <NUM>. As another example, the pores <NUM>, <NUM> may be positioned and may have certain properties to cause the wet part <NUM> to be formed without an area having a thickness that is below a certain threshold thickness, e.g., a thickness at which a weak point may be formed in the wet part <NUM>.

In some examples, the positions and/or properties of the pores <NUM>, <NUM>, <NUM>, and/or <NUM> may be determined through implementation of an algorithm that the processor <NUM> may execute. For instance, the algorithm may be a packing algorithm that may cause a maximum number of pores <NUM>, <NUM>, <NUM>, and/or <NUM> to respectively be added while causing the forming mold <NUM>, the forming screen <NUM>, the transfer mold <NUM>, and/or the transfer screen <NUM> to have certain levels of mechanical strength, e.g., to prevent weak points. In this example, the algorithm may be a sphere or ellipsoid packing algorithm or other suitable algorithm for determining placements of the pores <NUM>, <NUM>, <NUM>, and/or <NUM>.

As another example, the algorithm may be a packing algorithm that may position similarly sized pores <NUM> evenly across the forming mold <NUM> and/or similarly sized pores <NUM> evenly across the forming screen <NUM>. In this example, the processor <NUM> may execute the algorithm to place an array of pores <NUM> across a flattened version of the forming mold <NUM> or an array of pores <NUM> across a flattened version of the forming screen <NUM>. Similarly, the packing algorithm may position similarly sized pores <NUM> across the transfer mold <NUM> and/or similarly sized pores <NUM> across the transfer screen <NUM>. In this example, the processor <NUM> may execute the algorithm to place an array of pores <NUM> across a flattened version of the transfer mold <NUM> or an array of pores <NUM> across a flattened version of the forming screen <NUM>.

By placing the pores <NUM>, <NUM>, <NUM>, and/or <NUM> across the flattened versions, the processing resources and/or time consumed to arrange the pores <NUM>, <NUM>, <NUM>, and/or <NUM> may be reduced as compared with the processing resources and/or time consumed to implement other types of packing algorithms as the other types of packing algorithms may be more computationally intensive than the algorithm of this example. In any regard, following placement of the pores <NUM>, <NUM>, <NUM>, and/or <NUM>, the processor <NUM> may cause the digital models <NUM>, <NUM>-<NUM> of the forming mold <NUM>, the forming screen <NUM>, the transfer mold <NUM>, and/or the transfer screen <NUM> to include a curved section or multiple curved sections.

According to examples, the pores <NUM> in the transfer screen <NUM> may have properties, e.g., sizes and/or shapes, such that pressure may be applied onto the wet part <NUM> as described herein when a vacuum pressure is applied through the pores <NUM>. For instance, the pores <NUM> may be positioned and may have certain properties to cause pressure to be evenly applied across multiple surfaces of the wet part <NUM>. As other examples, the pores <NUM> may be positioned and may have certain properties to enable sufficient pressure to be applied across the multiple surfaces of the wet part <NUM> to suction liquid from the wet part <NUM> without, for instance, damaging the wet part <NUM>. In one regard, through application of substantially even pressure across multiple surfaces of the wet part <NUM>, the transfer screen <NUM> may be employed to remove a wet part <NUM> having a substantially vertical surface. In this regard, at least one of the multiple surfaces of the transfer screen <NUM> may extend substantially vertically (e.g., have a substantially zero draft) when removing the wet part <NUM> from the forming screen <NUM>.

The processor <NUM> may determine the locations at which the pores <NUM> are to be positioned in the transfer screen <NUM> to allow liquid to be suctioned from the wet part <NUM> when the transfer screen <NUM> is mounted to the transfer mold <NUM> and a vacuum pressure is applied to the transfer mold <NUM>. The processor <NUM> may determine the pore <NUM> locations that may cause, for instance, the even application across the transfer screen <NUM> through testing of previously fabricated transfer screens <NUM> and transfer molds <NUM>, through modeling of transfer screens <NUM> having various properties, and/or the like. In addition, the processor <NUM> may employ packing operations to determine the locations at which the pores <NUM> are to be placed in the transfer screen <NUM>. By way of example, the processor <NUM> may implement a packing algorithm that may cause a maximum number of pores <NUM> to be added to the transfer screen <NUM> while causing the transfer screen <NUM> to have a certain level of mechanical strength, e.g., to prevent weak points. In this example, the algorithm may be a sphere or ellipsoid packing algorithm or other suitable algorithm for determining placements of the pores <NUM>.

According to examples, the processor <NUM> may determine the locations of the pores <NUM> based on the properties (e.g., shapes and/or sizes) and/or locations of pores <NUM> in the forming mold <NUM>. In these examples, the processor <NUM> may obtain a digital model <NUM> of the transfer mold <NUM>, in which the transfer mold digital model <NUM> may include a plurality of pores <NUM> or a plurality of pores <NUM> are to be added algorithmically to the transfer mold digital model <NUM>. In addition, the processor <NUM> may determine the placements of the plurality of pores <NUM> in the transfer screen <NUM> with respect to liquid flow characteristics predicted to occur through the plurality of pores <NUM> in the transfer mold <NUM>. That is, based on how liquid is predicted or modeled to flow through the pores <NUM> in the transfer mold <NUM>, the pores <NUM> may be deterministically placed to cause the flow through the pores <NUM> to be substantially even across the transfer screen <NUM>. This may include, for instance, placing some pores <NUM> at higher density levels at some locations of the transfer screen <NUM> while some locations of the transfer screen <NUM> may include no pores <NUM>.

In addition, and as shown in <FIG>, a plurality of structural features, such as pillars <NUM>, may be provided between the surfaces of the transfer mold <NUM> and the transfer screen <NUM> that are respectively adjacent and face each other to enable liquid to flow laterally between the transfer mold <NUM> and the transfer screen <NUM>. As some of the pores <NUM> in the transfer screen <NUM> do not directly align with the pores <NUM> in the transfer mold <NUM>, the channels <NUM> formed by the structural features <NUM> may enable liquid to flow through those pores <NUM> in addition to the pores <NUM> that are directly aligned with respective pores <NUM> in the transfer mold <NUM>. The channels <NUM> may thus enable pressure to be applied through a larger number of the pores <NUM> and thus cause liquid to flow through the larger number of the pores <NUM>. The structural features <NUM> may be formed on the transfer screen <NUM> and/or the transfer mold <NUM>.

In examples in which the structural features <NUM> are provided between the transfer screen <NUM> and the transfer mold <NUM> to form the channels <NUM>, the processor <NUM> may determine the locations of the pores <NUM> also based on the predicted flow of liquid in the channels <NUM>.

Turning now to <FIG>, there is shown a flow diagram of an example method <NUM> for modifying a digital model <NUM> of a feature <NUM> to include a plurality of pores <NUM> at determined locations in the digital model <NUM> of the feature <NUM>. It should be understood that the method <NUM> depicted in <FIG> may include additional operations and that some of the operations described therein may be removed and/or modified without departing from the scope of the method <NUM>. The description of the method <NUM> is also made with reference to the features depicted in <FIG> for purposes of illustration. Particularly, the processor <NUM> depicted in <FIG> may execute some or all of the operations included in the method <NUM> using the elements depicted in <FIG>.

At block <NUM>, the processor <NUM> may obtain a digital model <NUM> of a screen <NUM>. At block <NUM>, the processor <NUM> may add a plurality of pores <NUM> to the digital model <NUM> of the screen <NUM>, in which the screen <NUM> may be implemented in a formation of a wet part <NUM> from a slurry <NUM> of a liquid and material elements. The processor <NUM> may add the pores <NUM> in any of the manners discussed herein.

At block <NUM>, the processor <NUM> may obtain a digital model <NUM> of a feature <NUM> to be added to the screen <NUM>, in which the feature <NUM> is to impart a detail <NUM> onto the wet part <NUM> during formation of the wet part <NUM>. At block <NUM>, the processor <NUM> may incorporate the digital model <NUM> of the feature <NUM> with the digital model <NUM> of the screen <NUM>. In addition, at block <NUM>, the processor <NUM> may identify locations in the digital model <NUM> of the feature <NUM> that are in line with pores <NUM> in the digital model <NUM> of the screen <NUM>. At block <NUM>, the processor <NUM> may modify the digital model <NUM> of the feature <NUM> to add pores <NUM> at the identified locations in the digital model <NUM> of the feature <NUM> to extend the pores <NUM> in the digital model <NUM> of the screen <NUM> through the digital model <NUM> of the feature <NUM>.

Some or all of the operations set forth in the method <NUM> may be contained as utilities, programs, or subprograms, in any desired computer accessible medium. In addition, the method <NUM> may be embodied by computer programs, which may exist in a variety of forms. For example, the method <NUM> may exist as computer-readable instructions, including source code, object code, executable code or other formats. Any of the above may be embodied on a non-transitory computer readable storage medium.

Examples of non-transitory computer readable storage media include computer system RAM, ROM, EPROM, EEPROM, and magnetic or optical disks or tapes. It is therefore to be understood that any electronic device capable of executing the above-described functions may perform those functions enumerated above.

Reference is now made to <FIG>, which shows a block diagram of an example apparatus <NUM> that may modify a digital model <NUM> of a feature <NUM> to include a plurality of pores <NUM> at determined locations in the digital model <NUM> of the feature <NUM>. It should be understood that the example apparatus <NUM> depicted in <FIG> may include additional features and that some of the features described herein may be removed and/or modified without departing from the scopes of the apparatus <NUM>. The description of the apparatus <NUM> is made with reference to <FIG> for purposes of illustration.

The apparatus <NUM> may be a computing system such as a laptop computer, a tablet computer, a desktop computer, a smartphone, or the like. As shown, the apparatus <NUM> may include the processor <NUM>. The apparatus <NUM> may also include a memory <NUM> that may have stored thereon machine-readable instructions (which may equivalently be termed computer-readable instructions) that the processor <NUM> may execute. The memory <NUM> may be an electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. The memory <NUM> may be, for example, Random-Access memory (RAM), an Electrically Erasable Programmable Read-Only Memory (EEPROM), a storage device, an optical disc, and the like. The memory <NUM>, which may also be referred to as a computer-readable storage medium, may be a non-transitory machine-readable storage medium, where the term "non-transitory" does not encompass transitory propagating signals.

As shown in <FIG>, the memory <NUM> may have stored thereon machine-readable instructions <NUM>-<NUM> that the processor <NUM> may execute. Although the instructions <NUM>-<NUM> are described herein as being stored on the memory <NUM> and may thus include a set of machine-readable instructions, the apparatus <NUM> may include hardware logic blocks that may perform functions similar to the instructions <NUM>-<NUM>. For instance, the processor <NUM> may include hardware components that may execute the instructions <NUM>-<NUM>. In other examples, the apparatus <NUM> may include a combination of instructions and hardware logic blocks to implement or execute functions corresponding to the instructions <NUM>-<NUM>. In any of these examples, the processor <NUM> may implement the hardware logic blocks and/or execute the instructions <NUM>-<NUM>. As discussed herein, the apparatus <NUM> may also include additional instructions and/or hardware logic blocks such that the processor <NUM> may execute operations in addition to or in place of those discussed above with respect to <FIG>.

The processor <NUM> may execute the instructions <NUM> to obtain a digital model <NUM> of a screen <NUM>, the digital model <NUM> including either a plurality of pores <NUM> or the digital model <NUM> may be processed to algorithmically add a plurality of pores <NUM> to the digital model <NUM> of the screen <NUM>. The screen <NUM> may be one of a forming screen <NUM> to be removably mounted on a forming mold <NUM> or a transfer screen <NUM> to be removably mounted on a transfer mold <NUM>.

The processor <NUM> may execute the instructions <NUM> to obtain a digital model <NUM> of a feature <NUM> to be added to the screen <NUM>, in which the feature <NUM> is to impart a detail <NUM> onto a wet part <NUM> during formation of the wet part <NUM> from a slurry <NUM> of a liquid and material elements. The processor <NUM> may execute the instructions <NUM> to incorporate the digital model <NUM> of the feature <NUM> with the digital model <NUM> of the screen <NUM>. As discussed herein, the processor <NUM> may add the digital model <NUM> of the feature <NUM> onto a surface of the digital model <NUM> of the screen <NUM> to cause the digital model <NUM> of the feature <NUM> to extend above the surface of the digital model <NUM> of the screen <NUM>, in which the feature <NUM> is to be added to the screen <NUM> when the screen <NUM> and the feature <NUM> are fabricated. Or, the processor <NUM> may add the digital model <NUM> of the feature <NUM> below a surface of the digital model <NUM> of the screen <NUM> to cause the digital model <NUM> of the feature <NUM> to extend below the surface of the digital model <NUM> of the screen <NUM>, in which the feature <NUM> is to be removed from the screen <NUM> when the screen <NUM> is fabricated.

The processor <NUM> may execute the instructions <NUM> to identify locations in the digital model <NUM> of the feature <NUM> that are in line with pores <NUM> in the digital model <NUM> of the screen <NUM>. In addition, the processor <NUM> may modify the digital model <NUM> of the feature <NUM> to add pores <NUM> at the identified locations in the digital model <NUM> of the feature <NUM> to extend the pores <NUM> in the digital model <NUM> of the screen <NUM> through the digital model <NUM> of the feature <NUM>.

Claim 1:
A non-transitory computer-readable medium (<NUM>) on which is stored machine-readable instructions that when executed by a processor, cause the processor to:
obtain (<NUM>) a digital model of a screen (<NUM>) to be fabricated by a three-dimensional (3D) fabrication system (<NUM>), the digital model of the screen including either a plurality of pores (<NUM>) or the digital model of the screen to be processed to algorithmically add a plurality of pores (<NUM>) to the digital model, wherein the screen is to be implemented in a formation of a wet part from a slurry of a liquid and material elements;
obtain (<NUM>) a digital model of a feature (<NUM>) to be added to a portion of the screen, wherein the feature is to impart a detail onto the wet part during formation of the wet part;
incorporate (<NUM>) the digital model of the feature with the digital model of the screen;
identify (<NUM>) locations in the digital model of the feature that are in line with pores in the digital model of the screen; and
modify (<NUM>) the digital model of the feature to add pores at the identified locations in the digital model of the feature to extend the pores in the digital model of the screen through the digital model of the feature.