Additive manufacturing in a gel-supported environment

Abstract

Additive manufacturing techniques are provided that can be used to form three-dimensional objects. A method for manufacturing a three-dimensional object is described. A nozzle (150) is placed in a gel (170) within a gel container (160). The nozzle is repositioned within the gel while depositing solidified material from the nozzle. The gel supports the solidified material at the location where it was deposited. The solidified material solidifies to form a solid object (180c).

Description

[Technical field]

[0001] This application claims priority to U.S. Provisional Patent Application No. 62 / 481,358, filed April 4, 2017, which is incorporated herein by reference in its entirety. [Background technology]

[0002] Traditional manufacturing typically involves moldings or other components that have fixed shapes, and these individual components are often assembled into more complex structures. This method is often expensive and can require a lot of manual labor. Additionally, the molds used for molding are expensive to produce and cannot be altered to the dimensions of the resulting molding.

[0003] Additive manufacturing is a general term for technologies that build three-dimensional objects by adding material layer by layer. Stereolithography (SLA) is an additive manufacturing technique that involves selective photopolymerization of polymers by exposing them to UV light.

[0004] Selective laser sintering (SLS), direct metal laser sintering (DMLS), and laser melting (SLM) are additive manufacturing techniques in which a thin layer of powder is distributed onto a substrate. In SLS and DMLS, the powder is selectively sintered by a laser. In SLM, the powder is selectively melted by a laser. Unlike SLA, which is typically used for polymers, SLS, DMLS, and SLS can be used for metals.

[0005] Fused deposition modeling (FDM), sometimes called fused filament fabrication (FFF), builds objects by selectively depositing molten material in predetermined paths, layer by layer.

[0006] One problem with existing technology is that it is too slow. Another problem with existing technology is that manufacturing complex shapes (such as unsupported overhangs) can require the creation of support structures that are removed during post-processing. Creating support structures often increases the design cost of the part and can increase the processing time to create the part. Additionally, the material cost to create the part increases because some or all of the support structures are discarded. Summary of the Invention [Problem to be solved by the invention]

[0007] The methods described herein relate to additive manufacturing techniques that can be used to form three-dimensional objects. [Means for solving the problem]

[0008] Described below is a method for making a three-dimensional object, which may include positioning a nozzle in a gel within a gel container; repositioning the nozzle within the gel while depositing a solidified material from the nozzle, the gel supporting the solidified material at the location where the solidified material was deposited; and solidifying the solidified material to form a solid mass that is the three-dimensional object.

[0009] Depositing the solidified material out of the nozzle may further include varying the rate at which the solidified material is deposited, for example, by varying pressure applied to one or more pistons to extrude the solidified material. Varying the position of the nozzle within the gel may further include varying the position of the nozzle at a varying rate.

[0010] The nozzle may be mounted on a multi-axis machine. Varying the position of the nozzle in the gel may include moving one or more axes of the multi-axis machine to which the nozzle is mounted. Varying the position of the nozzle in the gel may include repositioning the gel container.

[0011] Solidifying the solidifying material may include exposing the solidifying material to light or heat. Solidifying the solidifying material may include cooling the solidifying material. Solidifying the solidifying material may include exposing the solidifying material to light while depositing the solidifying material exiting the nozzle.

[0012] The solidification material may be a polymer, rubber, pulp, foam, metal, concrete, or epoxy resin. The rubber may be a silicone rubber.

[0013] The hardness of the solidified material may range from about Shore 00-10 to about Shore 90D when solidified.

[0014] The solidified material may be foam. The solidified foam may have a density of about 3 lb / ft 3 (pounds / foot cubed) ~ approx. 30 lb / ft 3 may be also possible.

[0015] The gel may be a suspension. The gel may contain carbomer or polyacrylic acid. The viscosity of the gel may be 20,000 cP (centipoise) to about 50,000 cP.

[0016] The nozzle may have a circular, rectangular, square, diamond, V-shaped, U-shaped, or C-shaped tip, and the solidified material exiting the tip may be deposited.

[0017] The solidification material may include two compounds that copolymerize. Solidifying the solidification material may include copolymerizing the two compounds. The nozzle further includes a mixing portion that mixes the two compounds as they exit the nozzle and are deposited.

[0018] Varying the position of the nozzle may include at least temporarily varying the position of the nozzle in the gel in three to eight axes simultaneously. Varying the position of the nozzle may include at least temporarily varying the position of the nozzle in the gel in five to eight axes simultaneously. Varying the position of the nozzle may include at least temporarily varying the position of the nozzle in the gel in three to six axes simultaneously. Varying the position of the nozzle may include at least temporarily varying the position of the nozzle in the gel in six axes simultaneously.

[0019] Varying the position of the nozzle may include varying the position of the nozzle to deposit solidified material on, around, or within other objects in the gel.

[0020] The nozzle may be a first nozzle, the solidification material may be a first solidification material, and the solid may be a first solid. The method may further include disposing a second nozzle in the gel within the gel container, and repositioning the second nozzle in the gel while depositing a second solidification material from the second nozzle, the gel supporting the second solidification material at the deposited position, and depositing the first and second solidification materials such that the first and second materials are in contact as deposited; and solidifying the second solidification material to form a second solid, the first and second solids being joined as the three-dimensional object. The first and second nozzles may have tips with different shapes. The first and second solidification materials may be different materials.

[0021] In the following, an apparatus for manufacturing a three-dimensional object is described, which may comprise a nozzle mounted on a multi-axis machine, a means for extruding a solidified material from said nozzle, and a gel container.

[0022] The apparatus may be configured as described herein to perform the methods described herein.

[0023] The methods described herein offer many advantages. In particular, the methods are fast. Compared to other additive manufacturing methods (such as FDM and SLM), printing in gel suspension in the disclosed embodiments of the additive manufacturing methods and systems described herein can be much faster, in some cases orders of magnitude faster, when printing parts with complex geometries (such as the geometry shown in FIG. 4). In some examples, the methods can be more than 300 times faster than existing methods. Since there is no need to deposit support structures, post-processing of the manufactured object is substantially reduced. For example, post-processing may simply include washing the object in water. There is no need to manually cut or otherwise remove support structures. Large objects can also be manufactured using the methods. The size of the gel container is the only factor limiting the size of the object that can be manufactured.

[0024] The speed and size can be increased when compared to known techniques, and the objects produced are of high quality. The solidification materials that can be used in the methods described herein include industrial grade materials. For example, the methods described herein can be used to make objects using silicone rubber, while other methods may require the use of elastomers that are not silicone. The methods can also be used to make materials from foam. Furthermore, the methods can be used to make materials from hard polymers, while other methods may require sintering of powders, and the resulting objects may have inferior mechanical properties. Since the methods described herein do not require layer-by-layer deposition, the objects formed do not have layering that can be mechanically inferior to products formed with a homogeneous cross section. [Brief description of the drawings]

[0025] The foregoing will become apparent from the following more particular description of illustrative embodiments that are illustrated in the accompanying drawings, in which like parts are designated with like reference numerals and in which the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the embodiments. [Figure 1] FIG. 1 is a diagram of a three-axis gantry machine with a two-component mixed deposition system for printing three-dimensional parts in a gel suspension. [Diagram 2] FIG. 1 is a diagram of a six-axis robotic arm with a two-component mixing deposition system for printing three-dimensional parts in a gel suspension. [Diagram 3] FIG. 1 is a diagram of a deposition system using a two-component solidification material where the solidification material flows from a mixing tip in a pneumatically controlled manner so that it is thoroughly mixed and forced out of the nozzle. [Figure 4] A comparison of different printing methods used on the same diagonally-shaped part. [Diagram 5] FIG. 1 illustrates various nozzle shapes, sizes and the resulting print paths. [Figure 6]A diagram of a large vat of gel suspending medium that prints a life-size chair suspended in 3D space. [Figure 7] FIG. 13 shows the printed portion of the chair on and / or around a metal frame inserted into a large tank. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0026] In the following, exemplary embodiments are described.

[0027] As used herein, the term "gel" refers to a colloid of particles dispersed in a liquid medium. Typically, the dispersed particles are crosslinked particles. The gel may be thixotropic. Most gels are predominantly liquid in weight but exhibit solid-like material properties due to a three-dimensional crosslinked network within the liquid.

[0028] The methods described herein relate to additive manufacturing in a gel suspension environment. Typically, a gel is placed in a container. A solidifying material, which can be in a molten or liquid state, is deposited through a nozzle and tool path.

[0029] In some embodiments, a multi-axis machine is used to control the path of the nozzle moving through the gel. Examples of multi-axis machines include gantry-type systems and industrial robotic arms. In general, various types of multi-axis machines and robotic arms are available. Gantry-style machines usually provide three axes of motion (axes of movement, i.e., x, y, and z). Robotic arms are often described according to the number of axes of rotation they have. For example, a 5-axis robotic arm can rotate in 5 separate axes of rotation, and a 6-axis robotic arm can rotate in 6 separate axes of rotation. In addition to axes of rotation, robotic arms can also be mounted on linear rails or gantry machines to provide linear axes of motion. As an example, a 6-axis robotic arm mounted on a linear rail can operate in 7 axes. As another example, a 6-axis robotic arm mounted on a gantry machine can operate in 7, 8, or 9 axes, depending on the particular operation of the gantry machine.

[0030] In addition to the axes of motion provided by a multi-axis machine, the container containing the gel can also be moved. For example, the gel container can be placed on a multi-axis gantry machine that can move the gel container in three separate axes that are different from the axes of motion of the multi-axis machine to which the nozzle is attached. The gel container can also be moved about an axis of rotation.

[0031] In some embodiments, the gel container moves in one axis and the nozzle moves in two axes. In some embodiments, the nozzle is stationary and the tank moves in two or three axes. In some embodiments, the tank is controlled by a gantry machine.

[0032] In some embodiments, the nozzle is controlled by a winch robot, also called a cable robot, in these embodiments, multiple cables control the movement of the nozzle in the x, y and z directions.

[0033] The combination of these components allows for extremely fast printing with a variety of materials. For example, a polymer in a molten state can exit the nozzle, be deposited, and solidify. For example, curing can include polymerization, which can be photopolymerization. In other embodiments, the polymer can be heated to accelerate the polymerization reaction rate. Chemically cured, photocured, or air / water cured plastics, rubbers, foams, and other liquids can be printed at large-scales, limited only by the size of the vessel or robotic device. With a variety of nozzles, flow rate, size, direction, and cross-sectional shape can be controlled. Similarly, complex three-dimensional tool paths can be created and printed in any orientation and direction in 3D space.

[0034] Existing additive manufacturing methods have limited industrial applications due to speed and size issues compared to other industrial manufacturing methods. The method described herein can increase printing speed by using a gel suspension that does not require a support material and does not slow down printing speed to wait for the material to solidify, unlike other three-dimensional printing methods. Also, unlike other additive manufacturing methods that take too long to print large structures (e.g., FDM, inkjet printing with liquid binders and powders (e.g., as achieved by 3D systems sold by ZCorp), SLA, SLS, and polyjet printing (e.g., CONNEX printers sold by Stratasys Ltd), manufacturing speed is also increased because the object is not built layer by layer. Instead, parts can be printed in three-dimensional space.

[0035] FIG. 4 is a comparison of different additive manufacturing printing methods used on the same braced part. In FDM printing, the part is cut into horizontal slices and horizontally sliced ​​support areas are printed to support the overhanging parts. In SLA printing, the part is sliced ​​horizontally and small top and bottom supports are printed to support the overhanging parts. In powder-based systems (e.g., SLS or ZCorp), the part is sliced ​​horizontally and the surrounding powder supports the overhanging parts. In the gel-supported environment method described herein, the part is printed immediately in the component orientation without being sliced ​​horizontally, effectively increasing the printing speed and structural continuity of the part, with the surrounding gel acting as a support material.

[0036] Post-processing time is also significantly reduced because no support structures are required. Previously, these support structures were manually removed or dissolved. With the present method, printing time is limited only by the speed of the machine and the curing time of the deposited solidified material (seconds to hours depending on the composition).

[0037] The printing scale is variable. By using a smaller nozzle tip, very small structures with fine features can be created. By using a larger nozzle, larger structures with larger features can be created.

[0038] FIG. 1 is a diagram of a three-axis gantry machine 100 used with two-component materials. The arm 110 is mounted on the gantry system 100 so that it can move in the x-axis, y-axis, and z-axis as shown. In this particular embodiment, pneumatic deposition can be performed via a pneumatic control system, which includes a chamber 120 for applying force to pistons 126a and 126b (see FIG. 3). Two chambers 130a and 130b are provided to contain two different materials. The materials are mixed in a mixing tip 140 and deposited out of a nozzle 150. A container or tank 160 contains a gel 170. As the arm 110 moves, the nozzle 150 moves in the gel and the two materials are extruded from the chambers 130a and 130b into the gel to form a three-dimensional object (printed part) 180a. FIG. 2 is a diagram of a six-axis robotic arm 200 using two-component materials. The rest is substantially the same as FIG. 1.

[0039] 3 is a diagram of a two-component material deposition system that is pneumatically controlled to flow through a mixing tip. Air enters through tube 124 and flows through pressure regulator 122 into chamber 120. This causes the air to exert a downward force on pistons 126a and 126b, pushing material out of chambers 130a and 130b, respectively. Solidified material (e.g., liquid) 180b is forced out of nozzle tip 150.

[0040] A motorized screw deposition system can also be used instead of the pneumatic deposition shown in Figure 3. For example, a motor can be used to apply a downward force to pistons 126a and 126b.

[0041] FIG. 6 illustrates the use of the invention described herein in forming a chair 180c.

[0042] 1. Deposition of solidified material 1.1.Materials The methods described herein use a deposition system to deposit solidification materials of various amounts and viscosities. The methods allow for easy liquid material flow / deposition, faster printing speeds, and the use of industrial grade materials, which are distinct advantages over other additive manufacturing methods. In some embodiments, the solidification material is one type of compound. In other embodiments, the solidification material is two different types of compounds that are copolymerized.

[0043] A variety of plastics, foams and rubbers have been tested so far, either one-part or two-part, air-cured or chemically cured materials. Most other methods rely on powdered materials with adhesive binders, selective sintering of powders, UV-curable polymers or hot-end filament extrusion, which inherently limits the materials available and the final material properties of the printed structure. The method described herein can be used to print with industrial grade materials such as polyurethane (PU) rubber, foams and plastics, resins, silicones, biomaterials, liquid wood pulp, concrete, liquid metal or any other solidifying material, greatly expanding the possibilities for industrial printing applications.

[0044] Examples of foams include urethane and foamed silicone. As used herein, foam refers to a material that has pockets of gas trapped in a liquid or solid. Foams are usually deposited in liquid form and then solidify.

[0045] Examples of plastics include chemically cured plastics such as urethanes, acrylics, and polymethylmethacrylates, radiation cured plastics, and moisture cured plastics.

[0046] Examples of resins include epoxy resins, phenol-formaldehyde resins, anaerobic resins, and cyanoacrylates.

[0047] Examples of silicones include addition and condensation cured silicone rubbers having hardness ranging from Shore 00-10 to Shore 60A upon solidification.

[0048] Examples of urethane rubbers include materials with hardness ranging from Shore 10A to Shore 90D.

[0049] Examples of biomaterials include bacteria, antibodies, lignin, growth media, yeast, cellular matrices, eukaryotic cells, non-eukaryotic cells, fungal medium, and seed / plant growth.

[0050] Examples of liquid wood pulps include cellulose, lignin, and other paper fiber mixes that contain both natural and synthetic fibers.

[0051] Examples of concrete include Portland cement or other hydraulic cements that harden by chemical reaction with water.

[0052] Examples of liquid metals include metals and alloys that have a melting point below about 100° C., such as field's metal, wood's metal, and rose's metal.

[0053] The method does not require layer-by-layer deposition. Instead, the nozzle can move and extrude in any orientation in three-dimensional space. As a result, the final printed product can have a stronger and more uniform material consistency and surface finish compared to products resulting from layer-based printing methods.

[0054] 1.2. Deposition The methods described herein can use syringe-type nozzles with openings of various shapes and sizes. The methods can also use two-component liquid extruders that can extrude input materials in 1:1, 2:1, 1:2, or other ratios. The nozzle sizes and shapes can accommodate different viscosities and different extrusion shapes or feature sizes. For example, more viscous materials require larger nozzles and higher pressures, while less viscous materials can use smaller nozzles and lower pressures. The extrusion pressure can be generated by pneumatic or mechanical actuation. Either actuation technique can be controlled to deposit the exact amount of liquid desired, stopped to prevent remaining liquid from being extruded, or, in some cases, physically removed material. The nozzle size can also allow for larger feature sizes and improved resolution of the printed part, or the amount and speed of material can be increased to reduce resolution. The deposition rate, nozzle size, and pressure in the cylinder are interrelated process variables. For example, to print faster, either the nozzle size or the pressure can be increased; otherwise, the volume of material extruded per unit distance traveled by the nozzle decreases as the nozzle speed increases. In other words, by changing the nozzle size or the applied pressure, the rate at which the solidified material is extruded from the nozzle can be affected, which in turn affects the rate at which the solidified material is deposited. The shape of the nozzle opening can also be changed to produce different effects on the printed part, similar to three-dimensional calligraphy techniques. Nozzles having circular, square, diamond, V-, U-, C-shapes, or nozzles of virtually any other shape can be used to create a variety of feature profiles. Examples of nozzle shapes are shown in FIG. 5. Any of the components can be used interchangeably or simultaneously in the system. For example, multiple nozzles can be used simultaneously to deposit two different materials at the same time.Alternatively, a tool changer may be used to interchange different nozzles, allowing a single complex design to be created having a variety of feature sizes, materials and / or profiles.

[0055] The mixing tip 140 can also be used to thoroughly mix two-part solidifying materials for chemical hardening. Liquid materials can have a variety of hardening times, from seconds to minutes or hours. The liquid materials can also have a variety of final hardening properties, including rigid (e.g., acrylonitrile butadiene styrene (ABS) plastic); elastic (e.g., rubber); expandable, flexible, or rigid foam; soluble (liquid); brittle; high temperature resistant, or theoretically any other property. The liquids can also be made virtually any color and viscosity with fillers and colorants. Any of these properties can be changed by using separate cartridges, continuous fill mechanisms to change properties during operation, multiple nozzles for multi-material printing or tool replacement to allow different materials to be used at different locations.

[0056] 2. Gel-type printing media 2.1. Composition A gel is used as a medium in which the solidified material is deposited, and as the solidified material is deposited, the gel supports the solidified material such that the solidified material is suspended within the gel.

[0057] A variety of gels are suitable. One specific example of a gel that has been used is a neutralized polyacrylic acid (Carbomer 940) gel. Carbomer 940 in the range of 0.25-1% by weight is thoroughly mixed in water so that no lumps remain. The mixture then has a low viscosity and low pH. Aqueous sodium hydroxide (NaOH) solution is slowly added to the Carbomer mixture until the pH is neutralized, and gently stirred to avoid air bubbles. At this point, the mixture becomes a high viscosity gel.

[0058] As discussed below, the viscosity of the gel may be adjusted by adjusting the pH, allowing the gel to receive and support objects of various densities.

[0059] Adjusting the viscosity of the gel also affects how the nozzle moves through the gel and the shape of the printed structures. For example, if both the gel and the solidifying material are low viscosity, the solidifying material may not stay precisely where it is deposited. Increasing the viscosity of the gel can ensure that the deposited solidifying material stays in the path it is deposited in, rather than flowing through the gel. Alternatively, in some embodiments, the viscosity of the solidifying material can be increased if the viscosity of the gel is too low.

[0060] 2.2. Controlling the buoyancy of an object The amount of Carbomer 940 used in the gel affects the subsequent support (floating) of foreign bodies, liquids or solids.

[0061] Higher percentages of carbomer result in gels with higher viscosity and shear stress. In this state, the gel can suspend materials with densities much lower or higher than the density of the gel itself. At 1% by weight of carbomer, the gel can suspend a 1 / 4 inch lead sphere.

[0062] Lower percentages of carbomer result in gels with lower viscosity and shear stress. In this state, the gel cannot suspend materials with densities much lower or higher than the density of the gel itself. At 0.25% by weight of carbomer, the gel cannot suspend 1 / 4 inch aluminum spheres.

[0063] The gel composition can be modified to suit the formation of a desired object. Typically, the viscosity of the gel may range from 20,000 cP to about 50,000 cP.

[0064] 2.3. Self-healing Gels are capable of self-healing after the nozzle has moved through the gel by reforming the gel to close gaps in void areas passed by the nozzle. As a result, air pockets in the gel are minimized. Lower shear stress (slower nozzle speed) allows the gel to self-heal quickly as the nozzle passes. As a result, the morphology of the deposition nozzle orifice is better maintained by depositing solidified material into a less viscous gel. High viscosity gels take longer to self-heal. As a result, liquid material may flow into cavities left by the tool before the gel can self-heal. This effectively stretches the circular deposit into droplets. The shape of the liquid material therefore varies depending on the relative viscosity of the gel and the speed at which the nozzle passes.

[0065] 3. Manufacturing equipment 3.1. Gantry System The process of liquid extrusion within the gel suspension can be precisely controlled using at least 3-axis CNC machines. A 3-axis gantry machine can be used to print 3-dimensional structures within the gel by mounting the cartridge and nozzle on the Z-axis. The nozzle is free to move in all three linear dimensions (x, y, and z), but the nozzle cannot rotate around the z-axis (when used on a 3-axis machine). Typically, printed parts are limited to 3-dimensional shapes with the nozzle oriented vertically.

[0066] A 5-axis gantry machine can also be used, in which the nozzle can move in all three linear directions (x, y, and z directions) and can rotate about the A and B axes. Because the nozzle can rotate, the solidified material does not necessarily have to be deposited from a vertical direction.

[0067] 3.2. Industrial Robot Arm In another embodiment, a six-axis industrial robot can be used to move the nozzle in the gel. Typically, a six-axis industrial robot can rotate in six different axes. As a result, the nozzle can be oriented in different directions, allowing printing laterally or rotating the nozzle as it moves in space. Similarly, more freedom can be allowed in the orientation of the robot and its relationship to the printing axes.

[0068] 3.3.Other Machines Other deposition machines are available, such as "delta" robots, cable bots, and even distributed printing processes using autonomous robots. This method does not require highly specialized machinery, but rather can accommodate almost any computer numerically controlled (CNC) machine capable of operating in three dimensions with multiple axes of control.

[0069] 3.4.Scale Both of these methods are scalable to large (several cubic meters) or small (several cubic millimeters) print volumes with high precision and / or high speed depending on the application. If small parts with high precision are required, then for gantry machines, small gel volumes can be used with very precise syringe tips. Conversely, if very large structures are required, then large gantry machines (tens of meters) or large industrial robots (5 meters or more) can be used. Theoretically, there is no limit to the size of the machine, but large gel baths are required and the larger the scale, the larger the amount of gel and the size of the container required. For industrial products on the order of a few millimeters to a few meters, this method is very promising and can provide a very fast and precise printing method with industrial grade materials.

[0070] 3.5. Speed ​​and Multiple Machines The manufacturing equipment outlined can operate at slow or fast speeds depending on the application, time constraints, or part features being printed. Typically, the robot arm controlling the nozzle needs to move slower for smaller parts and smaller features on the part. For larger parts and larger features on the part, the robot arm controlling the nozzle can move faster. Alternatively, a multi-robot printing method can be used where larger features are formed using one arm and smaller features are formed simultaneously using the other arm. This allows for different materials or interlocking parts, or other features not feasible with a single machine.

[0071] 4.Speed 4.1. Supporting material The present invention is much faster than existing printing methods for several reasons. The first factor that significantly increases speed is that excess design material for support is eliminated. Printed support material, which is required for FDM, SLA, or many other methods, is not required because various gels can support the deposited material. This significantly reduces the amount of material that needs to be printed, the time it takes to print, and the time it takes to remove excess material from the print. For example, a braced part with overhanging features can be printed by itself immediately in three-dimensional space without the need for supporting walls or columns.

[0072] By removing this limitation, it is also possible to print extremely complex structures that cannot be printed using other printing methods that require supports. For example, structures that are hollow but have complex shapes within the hollow cavities are difficult to create using other methods because they require support material to fill the cavities of the printed parts and extend from one printed part to the other. This excess material may not be removable, which can limit the complexity of possible shapes. With SLA or powder-based printing methods, the support material may also be trapped within the cavities, greatly increasing the amount of material required by the part.

[0073] 4.2.Post-printing process By printing in a viscous gel with a solidifying material that is chemically or air cured, the methods described herein reduce or eliminate complex and time-consuming post-processing. SLA printing methods typically require a support removal step that may require manual destruction of the support structure. There are also cleaning processes in alcohol baths to remove uncured polymer. These steps can be toxic, expensive, and extremely time-consuming. FDM and polyjet printing typically have a support dissolution step where the part is placed in a solution bath to remove the support material. This can also be toxic and extremely time-consuming. After printing the part for an extended period of time, the part must be placed in a solution bath for minutes or hours while the support is removed. Powder-based printing methods have an extremely cumbersome and time-consuming excavation process where the user must dig the part out of the powder bath. Using the methods described herein, when a part is printed, it can be cured immediately (or after a delayed time depending on the material selection) and then immediately removed from the gel by simply reaching in and pulling the part out. The part is then finished and ready to use with a simple water squirt to remove excess gel. This simple post-printing process can greatly expand the use of 3D printing in industrial applications, reducing hazards, making printing accessible to more people, and increasing the speed of post-processing.

[0074] 4.3.Layered Printing vs. Spatial Printing By performing spatial liquid deposition in a viscous gel medium, arbitrarily complex structures can be printed by themselves in three-dimensional space at once, without the need for software file preparation steps for slicing and layer-based printing.

[0075] In contrast, layer-by-layer processes require extremely complex software and generate large file sizes. Also, the slicing process often results in high failure rates or surface roughness of the printed parts. Complex 3D models must be algorithmically reconstructed in 2D paths, which can result in missing features, inaccurate paths, or reduced part resolution due to layer-by-layer material texture. Similarly, this layer-by-layer process significantly reduces the strength of the printed parts due to inhomogeneity. The method described herein does not include a layer-by-layer printing process and can produce perfectly homogeneous cross-sections within a print path of any orientation in three dimensions.

[0076] Similarly, the methods described herein can print parts extremely quickly when compared to layer-by-layer processes. When using layer-by-layer printing, the printing time can be calculated by multiplying the linear length of each two-dimensional path by the number of slices in the z-height. This significantly increases the time required to print each layer. With the methods described herein, the nozzle can print in any direction and with any feature size without the need to print layer-by-layer, significantly increasing the speed and feature possibilities of the printed part or object.

[0077] 5.Use 5.1. Printing in three-dimensional space The methods described herein allow small or large objects to be printed in three-dimensional space as if they were 2D drawings or sketches. In some embodiments, the nozzle can be moved manually in the gel without a multi-axis machine. In some embodiments, the robotic arm or gantry machine can be moved manually in the gel. The manual movements of the robotic arm or gantry machine can be recorded by software as the robotic arm or gantry machine is moved, forming a record of movements that can be reproduced for subsequent automated production. In other embodiments, the gantry machine or robotic arm can be controlled by a controller.

[0078] In some of the methods described herein, the structure to be created can be sent to the robot arm as a curve in 3D space. As an example, the three-dimensional curve can be generated in modeling software. This curve can be exported as a series of points in 3D space that the machine follows during the printing process. The output of the modeling software is typically machine code (e.g., G-code, Shopbot code, UR code, or various other formats of code files associated with the particular CNC machine being used). This process typically eliminates the need to use STL files (or mesh shape files) that are exported from the modeling software and then imported into slicing software to slice the STL / mesh shape into layers that form the tool path that the machine follows layer by layer. The slicing software generates the machine code for a regular printer. In the methods described herein that use multi-axis machines, a slicing step is not necessary and the machine code is generated from a series of three-dimensional points in space based on the original 3D curve. The machine code may include other parameters and values. For example, the machine code may include parameters to increase or decrease air pressure (e.g., turn air pressure on and off); parameters to adjust the speed of the machine (e.g., adjust the speed of the nozzle as it moves through the gel); and parameters to adjust the orientation of the nozzle as the machine moves it through the gel.

[0079] When connected to design software, modeling tools, or VR headsets, the methods described herein allow designers to sketch or design in the air and simultaneously print in the gel at the same speed and scale. This 1:1 design for production speed and length scale has not been possible before due to the time constraints inherent in physical manufacturing. Most fabrication methods are significantly slower (even for a quick sketch model) and cannot be as fast as sketching. This technology allows printed parts to be formed at the same speed as a robot or human moving an arm in the air.

[0080] 5.2. Printing on other items When a manufacturing machine (gantry or robot) picks up an object and places it in the gel, the machine can perform liquid printing on, around or inside the object. This capability allows for the continuous printing of materials with different properties in one build. Taking the creation of a chair as an example, a structure (in this case a metal structure) produced by another manufacturing method can be placed in the gel. The back of the chair, usually made of a soft rubber material, can be printed around the placed metal structure. The robot can then switch to print a foam material as the seat cushion of the chair, connected directly to the metal structure. This method allows the incorporation of fastening details such as screws, bolts or other connectors, allowing for a hybrid manufacturing method. Many objects (flexible or rigid) with different materials can be placed or placed in the gel, which becomes the substrate for further building processes. Even fabric can be placed in the gel and printed on it.

[0081] 7 is an illustration of the creation of a chair using the methods described herein. A metal frame 190 can be placed in a tank 160 of gel 170. A chair cover and frame 180d can be printed on and / or around the metal frame 190 to form a taut surface on the chair. This method allows for hybrid printing incorporating other parts (e.g., industrially produced parts) in the gel suspension.

[0082] 5.3.Curing time Printed solidifying materials can be configured to cure very quickly or slowly depending on the application: faster cure times can reduce overall production time, slower cure times allow for more complete bonding when printing intersecting paths, and slower cure times allow for bonding of liquid printed structures to objects placed in the gel.

[0083] 5.4. Complex Tool Paths Another possible advantage of this technique is that fully interlocking three-dimensional parts can be formed without support material or cavity filling. For example, printing of woven or knit structures can now be done using multiple robots depositing liquids simultaneously, or with complex tool paths that would not be possible otherwise. Using 6-axis industrial robots, complex tool paths with different nozzle extrusion directions can be used, almost like calligraphy. It is also possible to print under, next to or over other prints / objects in the gel.

[0084] 5.5.Post-processing Various forms of post-curing (such as UV or temperature settings to change the material's properties) can be implemented. After removal from the gel bath, the part can be easily washed with water to remove excess gel, or coated with some material to strengthen the part, colored, further cured, or any number of post-treatment steps. For example, if a ceramic material is printed in the gel or in a wood or metal slurry, the printed part can be cured in the gel, removed, and placed in an oven for post-treatment. This allows the strength of the part to be greatly improved, such as through a post-printing firing or sintering process as used in ceramic or metal manufacturing, or by the performance of many other interesting materials.

[0085] 5.5. Use of Materials The elimination of printed support materials and the truly three-dimensional nature of this printing method allows for much less material to be used in the printed part. This method does not require a bath or bed full of powder or liquid resin. Similarly, layer-based methods and additive printed support materials result in a significant waste in the total amount of material used compared to the material required for the final part. The method described herein eliminates the waste of material.

[0086] 6. Advantages and Improvements over Existing Methods This technology offers a significant improvement over existing three-dimensional printing methods, including SLA, SLA, FDM, polyjet, and powder-based printing. Thus far, three-dimensional printing has not made a significant impact on industrial manufacturing due to: 1) long printing times compared to injection molding or other manufacturing methods; 2) relatively small build volumes, limiting practical applications; and 3) only low-quality printable plastics and other materials are available, and the properties of these materials are inferior to industrial materials. The method described herein significantly improves on these issues.

[0087] The method described herein does not require a support material to build overhangs or complex three-dimensional structures, making the structures significantly faster to form. FDM, polyjet and SLA techniques require a support that significantly increases the time required for printing and the post-printing time due to the need to remove the support manually or by dissolving. The method described herein can print the same complex three-dimensional shapes without a support, while reducing the need for unnecessary additional materials, unnecessary printing time and unnecessary post-printing processes. Once the structure is printed and the solidified material has solidified (e.g., cured), the structure is removed from the gel and simply washed with water to complete. The method uses the structure of the gel material to suspend the print in three-dimensional space, allowing for non-layer-based printing where the nozzle is free to move in three axes at any time.

[0088] This technique also significantly increases printing speed by eliminating the requirement to print in successive layers. Almost all currently available printing methods require each layer to be printed one after the other. This significantly increases the time it takes to print tall or complex three-dimensional shapes and requires sophisticated digital "slicing" techniques that generate large file sizes. For example, if a wireframe structure is printed using FDM, SLA, SLS, powder-based printing or polyjet, the structure would need to be sliced ​​into multiple layers and then printed in straight line paths at each layer. The ends of the wireframe structure would also need to have support material printed underneath due to cantilevered and unsupported features. The method described herein allows for the elimination of support material and slicing by simply drawing these lines in three-dimensional space. Another feature that increases printing speed compared to other freeform or aerial three-dimensional printing methods is the speed of extrusion. Other methods require the material to cure or solidify before the machine can move to the next layer or continue to move the nozzle. This significantly reduces the speed at which the robot or printer can move. In the methods described herein, because the material is suspended in a gel in three-dimensional space, the nozzle can continue to move rapidly and continue to extrude material that becomes suspended and solidifies (e.g., chemically hardened) behind the nozzle path. Due to these factors, it is believed that printing speeds can be increased by orders of magnitude compared to conventional printing methods.

[0089] Compared to conventional three-dimensional printing methods, the methods described herein can be scaled from very small and high resolution to large. The methods are significantly faster than any other methods, allowing for much larger structures to be built in less time. For example, a 6 cubic inch material can take 24-48 hours to print with an SLA machine, but can be printed in minutes with the methods described herein. The methods can also be scaled by using larger gel tanks and larger industrial robots or gantry machines, allowing for very large structures to be produced very quickly. The speed and scale of printing can then be comparable to other industrial methods such as injection molding or machining. Especially considering the assembly time of conventional products, the methods described herein can be a game changer in manufacturing, as the entire product can be printed simultaneously, potentially eliminating the need for assembly.

[0090] One of the most notable advances over traditional three-dimensional printing methods is the improvement in material properties. The method prints solidifying materials in a liquid or molten state and chemically hardens the materials, allowing the use of realistic, industrially produced materials. Some examples of materials that can be used include polyurethane (PU) rubber, foam, plastic, or any other liquid or molten material. FDM printing produces a filament that then needs to be heated and extruded in liquid form, and then cooled and solidified into a three-dimensional structure. This method limits the types of materials that can be used, and the layered nature of the FDM printing method significantly reduces the structural integrity of the printed parts compared to injection molding. Materials are even more limited in SLS printing, as it requires the material to be powdered and then sintered, limiting the range of materials available. The methods described herein use the same materials currently available in many industrial manufacturing methods, and these materials are cured chemically or by other methods (e.g., photopolymerization) without the need for heating, sintering, or hot extrusion. Also, because the method does not rely on continuous layering, the parts can be as strong as parts made by traditional manufacturing methods. Additionally, the methods described herein can also be used to print liquid slurry wood, biomaterials, low temperature liquid metals, cement, or other types of materials that can be extruded onto a gel support.

[0091] 7.Applications The methods described herein can be used to make a variety of products, including apparel and sporting goods; fabrication and manufacturing; aeronautical and automotive applications; furniture and interior products; architecture, engineering and construction; toys and consumer goods, etc. Below are some examples of products that fall into these categories:

[0092] Apparel and Sporting Goods: 1:1 printing of sporting goods (bikes, boards, boots, shoes, helmets, pads, etc.); printed fabrics; marketing / commercial / PR applications using innovative new methods for in-store or high-tech appeal; large or small parts made of industrial quality materials (foam, rubber, plastic) that are highly customized and can exceed the speed of existing manufacturing methods; new design methods using physical 3D 1:1 size / speed sketching.

[0093] Fabrication and manufacturing: large-scale tooling, prototyping and fixturing; large or small parts made of industrial quality materials (foam, rubber, plastic) that can exceed the speed of existing manufacturing methods and are highly customized; hybrid approaches using multiple manufacturing methods (i.e., a welded or cast metal part is inserted into a gel and receives a liquid printed part in / around / on the surface of this metal part).

[0094] Aerospace and Automotive Applications: Large printed parts for interior applications (panels, seats, shades, dashboards, ceilings, floors); medium printed parts (seat cushions / structures, engine parts, brackets, connectors); large printed parts for exterior panels; tooling, prototyping and fixture manufacturing; large or small parts made of industrial quality materials (foam, rubber, plastic) that can exceed the speed of existing manufacturing methods and are highly customized; new design methods with physical 3D 1:1 size / speed sketching.

[0095] Furniture and Interior Products: large printed parts for interior applications (screens, fixtures, etc.); medium printed parts (seat cushions, seat structures, backrests / upholstery, tables, desks, stools, shelves, etc.); tooling, prototyping and fixture manufacturing; marketing / commercial / PR applications using innovative new methods for in-store applications or high-tech appeal; large or small parts made of industrial quality materials (foam, rubber, plastic), highly customized, that can exceed the speed of existing manufacturing methods; new design methods using physical 3D 1:1 size / speed sketching.

[0096] Architecture, Engineering and Construction: Large scale tooling (blades, concrete work, support structures); final structure (walls, surfaces, skins / panels, 1:1 details); on-site fabrication methods for speed / scale construction; new design methods using physical 3D 1:1 size / speed sketching.

[0097] Toys and Consumer Goods: 1:1 consumer goods / toys printing (bikes, boards, boots, shoes, helmets, pads, etc.); large or small parts made of highly customized, industrial quality materials (foam, rubber, plastic) that can exceed the speed of existing manufacturing methods; new design methods with physical 3D 1:1 size / speed sketching. Related Applications

[0098] The teachings of all patents, publications and references cited herein are hereby incorporated by reference in their entirety.

[0099] While exemplary embodiments have been specifically described and illustrated, those skilled in the art will recognize that the present invention may be made in various forms and details without departing from the scope of the embodiments encompassed by the appended claims. The present invention includes the following embodiments. [Aspect 1] a) placing a nozzle into a gel within a gel container; b) repositioning the nozzle within the gel while depositing solidified material exiting the nozzle, the gel supporting the solidified material at the location where the solidified material was deposited; c) solidifying the solidification material to form a three-dimensional solid object; A method for manufacturing a three-dimensional object comprising the steps of: [Aspect 2] The method of claim 1, wherein the nozzle is mounted on a multi-axis machine, and changing the position of the nozzle in the gel comprises operating one or more axes of the multi-axis machine to which the nozzle is mounted. [Aspect 3] 3. The method of claim 1 or 2, wherein depositing the solidified material exiting the nozzle further comprises varying a rate at which the solidified material is deposited. [Aspect 4] 3. The method of claim 1 or 2, wherein varying the position of the nozzle in the gel further comprises varying the position of the nozzle at a varying rate. [Aspect 5] 3. The method of claim 1 or 2, wherein changing the position of the nozzle in the gel comprises changing the position of the gel container. [Aspect 6] 3. The method of claim 1 or 2, wherein solidifying the solidifying material comprises exposing the solidifying material to light or heat. [Aspect 7] 3. The method of claim 1 or 2, wherein solidifying the solidified material comprises cooling the solidified material. [Aspect 8] 3. The method of claim 1 or 2, wherein solidifying the solidified material comprises exposing the solidified material to light while depositing the solidified material exiting the nozzle. [Aspect 9] 3. The method of claim 1 or 2, wherein the solidification material is a polymer, rubber, pulp, foam, metal, concrete, or epoxy resin. [Aspect 10] 10. The method of claim 9, wherein the rubber is a silicone rubber. [Aspect 11] 3. The method of any one of the preceding claims, wherein the hardness of the solidified material upon solidification ranges from about Shore 00-10 to about Shore 90D. [Aspect 12] 3. The method of claim 1 or 2, wherein the solidification material is a foam. [Aspect 13] 13. The method of claim 12, wherein the solidified foam has a density of about 3 lb / ft 3 ~30lb / ft 3 How to be. [Aspect 14] The method according to any one of the preceding claims, wherein the gel is a suspension. [Aspect 15] 15. The method of claim 14, wherein the gel comprises a carbomer or a polyacrylic acid. [Aspect 16] The method according to aspect 1 or 2, wherein the viscosity of the gel is about 20,000 cP to about 50,000 cP. [Aspect 17] The method of any one of claims 1 to 2, wherein the nozzle has a circular, rectangular, square, diamond, V-shaped, U-shaped, or C-shaped tip, and the solidified material exiting the tip is deposited. [Aspect 18] 3. The method of claim 1 or 2, wherein the solidifying material comprises two compounds that copolymerize, and solidifying the solidifying material comprises copolymerizing the two compounds. [Aspect 19] 19. The method of claim 18, wherein the nozzle further comprises a mixing portion that mixes the two compounds as they exit the nozzle and are deposited. [Aspect 20] 3. The method of claim 1 or 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in 3 to 8 axes simultaneously. [Aspect 21] 3. The method of claim 1 or 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in 5 to 8 axes simultaneously. [Aspect 22] 3. The method of claim 1 or 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in 3 to 6 axes simultaneously. [Aspect 23] 3. The method of claim 1 or 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in six axes simultaneously. [Aspect 24] 3. The method of claim 1 or 2, wherein altering the position of the nozzle comprises altering the position of the nozzle to deposit solidified material on, around, or within other objects in the gel. [Aspect 25] 3. The method of claim 1 or 2, wherein the nozzle is a first nozzle, the solidification material is a first solidification material, and the solid is a first solid, the method further comprising: d) placing a second nozzle within the gel container into the gel; e) repositioning the second nozzle in the gel while depositing a second solidification material from the second nozzle, the gel supporting the second solidification material at the deposited position, and depositing the first and second solidification materials such that the first and second materials are in contact in the deposited state; f) solidifying the second solidification material to form a second solid body, wherein the first and second solid bodies are joined as the three-dimensional object. The method includes: [Aspect 26] 26. The method of claim 25, wherein the first and second nozzles have tips with different shapes. [Aspect 27] 26. The method of claim 25, wherein the first and second solidification materials are different materials. [Aspect 28] a) a nozzle mounted on a multi-axis machine; b) means for extruding solidified material from said nozzle; c) a gel container; A three-dimensional object manufacturing apparatus comprising:

Claims

1. a) placing a nozzle into a gel within a gel container; b) pneumatically or electrically controlling the flow of compounds from said nozzle according to pre-programmed software defined functions for designing a three-dimensional object and a method for rendering said three-dimensional object using said nozzle, said flow including parameters for increasing or decreasing the pressure in said nozzle and the speed of movement of said nozzle through the gel; c) repositioning the nozzle within the gel while depositing solidified material that exits the nozzle and becomes part of the three-dimensional object, the gel supporting the solidified material such that the solidified material is suspended within the gel; d) solidifying the solidification material in the gel to form a solid mass that is the three-dimensional object, the nozzle is a first nozzle, the solidification material is a first solidification material, and the solid is a first solid, the method further comprising: e) placing a second nozzle within the gel container; f) pneumatically or electrically controlling the flow of compound from the second nozzle according to pre-programmed software defined functions of the design of the three-dimensional object and the method of rendering the three-dimensional object using the second nozzle, the flow including parameters to increase or decrease the pressure in the second nozzle and the speed of movement of the second nozzle through the gel; g) repositioning the second nozzle within the gel while depositing a second solidification material exiting the second nozzle, the gel supporting the second solidification material, and the simultaneous or near simultaneous deposition of the first and second solidification materials may be performed such that the first and second solidification materials are in contact as deposited; h) solidifying the second solidification material to form a second solid body, wherein the first and second solid bodies are joined as the three-dimensional object; the gel returning to its original location after being moved by the first or second nozzle (except in the areas where the first and second solidification materials were deposited); The method wherein the gel is an aqueous gel.

2. 2. The method of claim 1, wherein the nozzle is mounted to a multi-axis machine, and wherein changing the position of the nozzle in the gel includes operating one or more axes of the multi-axis machine to which the nozzle is mounted.

3. 3. The method of claim 1 or 2, wherein depositing the solidified material exiting the nozzle further comprises varying a rate at which the solidified material is deposited.

4. 3. The method of claim 1 or 2, wherein varying the position of the nozzle in the gel further comprises varying the position of the nozzle at a varying rate.

5. 3. The method of claim 1 or 2, wherein the changing the position of the nozzle in the gel comprises changing the position of the gel container.

6. The method of claim 1 or 2, wherein solidifying the solidifying material comprises exposing the solidifying material to light or heat.

7. The method of claim 1 or 2, wherein solidifying the solidifying material comprises cooling the solidifying material.

8. 3. The method of claim 1 or 2, wherein solidifying the solidifiable material comprises exposing the solidifiable material to light while depositing the solidifiable material exiting the nozzle.

9. 3. The method of claim 1 or 2, wherein the solidification material is a polymer, rubber, pulp, foam, metal, concrete, or epoxy resin.

10. 10. The method of claim 9, wherein the rubber is a silicone rubber.

11. 3. The method of claim 1 or 2, wherein the hardness of the solidified material ranges from about Shore 00-10 to about Shore 90D upon solidification.

12. 3. The method of claim 1 or 2, wherein the solidifying material is a foam.

13. 13. The method of claim 12, wherein the density of the solidified foam is about 3 lb / ft. 3 ~About 30lb / ft 3 How to be.

14. 3. The method of claim 1 or 2, wherein the gel is a suspension.

15. 3. The method of claim 1 or 2, wherein the gel comprises a carbomer.

16. 3. The method of claim 1 or 2, wherein the viscosity of the gel is from about 20,000 cP to about 50,000 cP.

17. 3. The method of claim 1 or 2, wherein the nozzle has a circular, rectangular, square, diamond, V-shaped, U-shaped, or C-shaped tip, and the solidified material exiting the tip is deposited.

18. 3. The method of claim 1 or 2, wherein the solidification material comprises two compounds that copolymerize, and solidifying the solidification material comprises copolymerizing the two compounds.

19. 20. The method of claim 17, wherein the nozzle further comprises a mixing section for mixing the two compounds as they exit the nozzle and are deposited.

20. 3. The method of claim 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in three to eight axes simultaneously.

21. 3. The method of claim 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in five to eight axes simultaneously.

22. 3. The method of claim 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in three to six axes simultaneously.

23. 3. The method of claim 2, wherein varying the position of the nozzle comprises at least temporarily varying the position of the nozzle within the gel in six axes simultaneously.

24. 3. The method of claim 1 or 2, wherein altering the position of the nozzle includes altering the position of the nozzle to deposit solidified material on, around, or within other objects in the gel.

25. 2. The method of claim 1, wherein the first and second nozzles have tips with different shapes.

26. 10. The method of claim 1, wherein the first and second solidification materials are different materials.

27. a) a first nozzle and a second nozzle mounted on a multi-axis machine; b) means for extruding a first solidification material through said first nozzle and a second solidification material through said second nozzle; c) a gel container; and d) a pneumatic or electrical control system configured to control the flow of compounds from the first and second nozzles according to a defined function of pre-programmed software defining a design of the three-dimensional object and a method of rendering the three-dimensional object using the first and second nozzles, the flow including parameters for increasing or decreasing the pressure in the first and second nozzles and the speed of movement of the first and second nozzles through the gel, the multi-axis machine positions the first nozzle in the gel within the gel container; the gel supports the first and second solidification materials such that the first and second solidification materials are suspended within the gel; repositioning the first and second nozzles within the gel while the multi-axis machine deposits solidified material that exits the first and second nozzles and becomes part of the three-dimensional object; The simultaneous or near simultaneous deposition of the first and second solidification materials may be performed such that the first and second solidification materials are in contact in the deposited state; the first and second solid bodies are joined as the three-dimensional object; the gel returning to its original location after being moved by the first or second nozzle (except in the areas where the first and second solidification materials were deposited); The device, wherein the gel is an aqueous gel.

28. A method for manufacturing a gel container comprising: a) disposing a nozzle in a gel within a gel container; b) pneumatically or electrically controlling the flow of compounds from said nozzle according to pre-programmed software defined functions for designing a three-dimensional object and a method for rendering said three-dimensional object using said nozzle, said flow including parameters for increasing or decreasing the pressure in said nozzle and the speed of movement of said nozzle through the gel; c) repositioning the nozzle within the gel while depositing solidified material that exits the nozzle and becomes part of the three-dimensional object, the gel supporting the solidified material such that the solidified material is suspended within the gel; d) solidifying the solidification material in the gel to form a solid mass that is the three-dimensional object, The method, wherein the nozzle is a first nozzle, the solidifying material is a first solidifying material, and the solid is a first solid.

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