WO2018199967A1

WO2018199967A1 - Supply of fiduciary objects in 3d object formations

Info

Publication number: WO2018199967A1
Application number: PCT/US2017/029963
Authority: WO
Inventors: Sunil KOTHARI; Jun Zeng; Gary J. Dispoto; Wesley R. Schalk
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2017-04-27
Filing date: 2017-04-27
Publication date: 2018-11-01

Abstract

According to an example, an apparatus may include a processor and a memory on which is stored machine readable instructions that are to cause the processor to determine a number of 3D object formation cycles that a batch of build material particles has undergone. The instructions may also cause the processor to identify a feature for a fiduciary object to be supplied among the build material particles, in which the feature is based upon to the determined number of 3D object formation cycles, and control a supply device to supply a fiduciary object having the identified feature among the build material particles.

Description

SUPPLY OF FIDUCIARY OBJECTS IN 3D OBJECT FORMATIONS BACKGROUND

[0001] In three-dimensional (3D) printing, an additive printing process is often used to make three-dimensional solid parts from a digital model. 3D printing is often used in rapid product prototyping, mold generation, mold master generation, and short-run manufacturing. Some 3D printing techniques are considered additive processes because they involve the application of successive layers of material to an existing surface (template or previous layer). This is unlike traditional machining processes, which often rely upon the removal of material to create the final part. 3D printing often requires curing or fusing of the building material, which for some materials may be accomplished using heat-assisted extrusion, melting, or sintering, and for other materials may be performed through curing of polymer-based build materials.

BRIEF DESCRIPTION OF THE DRAWINGS

[0002] Features of the present disclosure are illustrated by way of example and not limited in the following figure(s), in which like numerals indicate like elements, in which:

[0003] FIG. 1 A shows a block diagram of an example apparatus that may be implemented to supply a fiduciary object among build material particles;

[0004] FIG. 1 B shows the example apparatus depicted in FIG. 1 A delivering an agent onto build material particles;

[0005] FIG. 2 shows a block diagram of an example 3D printer;

[0006] FIG. 3 shows a flow diagram of an example method for introducing an item having a feature that indicates an estimated number of 3D object formation cycles to which build material particles have been subject; and

[0007] FIG. 4 shows a flow diagram of an example method for introducing items among build material particles.

DETAILED DESCRIPTION

[0008] Disclosed herein are apparatuses and methods that may be employed to supply a fiduciary object among build material particles. Generally speaking, the fiduciary object may be a visual indicator of the age of the build material particles among which the fiduciary object 130 is supplied. The age may be defined in terms of the number of 3D object formation cycles that the build material particles have undergone or been subjected. As discussed herein, the build material particles that are not used to form 3D objects during formation cycles may be reclaimed for recycling and/or reuse. Recycling of the build material particles may be practical and may result in significant cost savings as fresh build material particles used in 3D printing operations may be relatively expensive. However, there may be limits on the number of times that build material particles may be recycled because the build material particles may become degraded during 3D object formation cycles, such as when heat is applied to the build material particles. Additionally, the states of the build material particles may not be readily discernable based upon a visual inspection of the build material particles.

[0009] According to examples, the fiduciary objects disclosed herein may provide a non-invasive and non-cumbersome manner of indicating the number of times that the build material particles have undergone the 3D object formation cycles. As the fiduciary objects may remain with reclaimed build material particles, e.g., collected with the reclaimed build material particles, the ages of the reclaimed build material particles may be determined from the fiduciary objects even in instances in which the reclaimed build material particles are removed from the 3D printers in which the reclaimed build material particles underwent a 3D object formation cycle.

[0010] According to examples, a mixture containing reclaimed build material particles having different ages may be used to form a 3D object. In these examples, the mixture may include a plurality of fiduciary objects having different features with respect to each other and may thus denote different ages. By way of particular example, the age of the mixture may be determined to be equivalent to the oldest identified age. In other examples, heuristics may be implemented based upon various factors including probabilities of finding fiduciary objects having certain features, densities of the fiduciary objects having certain features, etc., to estimate the age of the mixture.

[0011] Through implementation of the apparatuses and methods disclosed herein, the number or an estimated number of times build material particles or a mixture of build material particles have been subjected to 3D object formation cycles may accurately and relatively easily be determined through an examination of fiduciary objects that are supplied among the build material particles. Using this information, an operator or a processor may determine whether the build material particles have been subjected to too many 3D object formation cycles to be used in a current 3D object formation operation. For instance, a determination may be made that because the build material particles have undergone too many 3D object formation cycles, that the build material particles may not be guaranteed to form a 3D object with a certain level of quality.

[0012] Before continuing, it is noted that as used herein, the terms "includes" and "including" mean, but is not limited to, "includes" or "including" and "includes at least" or "including at least." The term "based on" means "based on" and "based at least in part on."

[0013] Reference is first made to FIGS. 1 A and 1 B. FIG. 1 A shows a block diagram of an example apparatus 100 that may be implemented to supply a fiduciary object among build material particles. FIG. 1 B shows the example apparatus 100 depicted in FIG. 1A delivering an agent onto build material particles. It should be understood that the apparatus 100 depicted in FIGS. 1 A and 1 B may include additional components and that some of the components described herein may be removed and/or modified without departing from a scope of the apparatus 100 disclosed herein.

[0014] The apparatus 100 may be a computing apparatus, e.g. , a personal computer, a laptop computer, a tablet computer, a smartphone, or the like. In these examples, the apparatus 100 may be separate from a 3D fabricating device and may communicate instructions to the 3D fabricating device over a direct or a network connection. In other examples, the apparatus 100 may be part of a 3D fabricating device. In these examples, the apparatus 100 may be part of a control system of the 3D fabricating device and may communicate instructions to forming components of the 3D fabricating device, for instance, over a bus. By way of example, the processor 102 may communicate instructions to or otherwise control the forming components, which may be components of the 3D fabricating device, to fabricate a 3D object from layers of build material particles.

[0015] As shown in FIG. 1 A, the apparatus 100 may include a processor 102 that may control operations of the apparatus 100. The processor 102 may be a semiconductor-based microprocessor, a central processing unit (CPU), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a graphics processing unit (GPU), a tensor processing unit (TPU), and/or other hardware device. The apparatus 100 may also include a memory 1 10 that may have stored thereon machine readable instructions 1 12-1 16 (which may also be termed computer readable instructions) that the controller 102 may execute. The memory 1 10 may be an electronic, magnetic, optical, or other physical storage device that contains or stores executable instructions. The memory 1 10 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 1 10, 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.

[0016] The processor 102 may fetch, decode, and execute the instructions 1 12 to determine a number of 3D object formation cycles that a batch 120 of build material particles 122 has undergone. Each 3D object formation cycle may include a cycle in which some or all of the build material particles 122 in the batch 120 are applied onto a build platform and the 3D object is formed from some of the build material particles on the build platform and some or all of the build material particles 122 that are not used to form the 3D object are recycled. The number of 3D object formation cycles may thus be the number of times that the unused build material particles 122 have been recycled. [0017] The build material particles 122 may be formed of any suitable material including, but not limited to, polymers, metals, and ceramics and may be in the form of a powder. Additionally, the build material particles 122 may be formed to have dimensions, e.g., widths, diameters, or the like, that are generally between about 5 μιη and about 100 μιη. In other examples, the build material particles 122 may have dimensions that are generally between about 30 μιη and about 60 μιη. The build material particles 122 may generally have spherical shapes, for instance, as a result of surface energies of the particles 122 and/or processes employed to fabricate the particles 122. The term "generally" may be defined as including that a majority of the particles 122 have the specified sizes and spherical shapes. In other examples, the term "generally" may be defined as a large percentage, e.g., around 80% or more of the particles 122 have the specified sizes and spherical shapes.

[0018] In some examples, the processor 102 may determine the number of 3D object formation cycles that the batch 120 of build material particles 122 has undergone through receipt of the number from an operator. In some examples, the processor 102 may track the number of times that the batch 120 of build material particles 122 has undergone the 3D object formation cycles in a particular 3D fabricating device. The first time that the batch 120 of build material particles 122 is being used, the processor 102 may determine that the batch 120 has not undergone any 3D object formation cycles and the processor 102 may track each additional time that the build material particles 122 in the batch 120 are reused in subsequent 3D object formation cycles.

[0019] The processor 102 may fetch, decode, and execute the instructions 1 14 to identify a feature for a fiduciary object 130 to be supplied among the build material particles. Generally speaking, a fiduciary object 130 may be an object that may be interspersed or otherwise contained with the batch 120 of build material particles 122 and that may indicate a property of the build material particles 122. For instance, a fiduciary object 130 may be a visual indicator of an age of the build material particles 122 in terms of the number of times that the build material particles 122 have undergone 3D object formation cycles. [0020] The age of the build material particles 122 in a batch 120 may be indicated by a feature of the fiduciary object 130, in which the feature may be based upon the number of 3D object formation cycles that the batch 120 of build material particles 122 has undergone and may also include the current 3D object formation cycle. The age of the build material particles 122 may thus be the number of previous 3D object formation cycles plus the current 3D object formation cycle. The feature may be a physical feature or characteristic such as color, texture, shape, pattern, or the like, and different features may represent different ages of build material particles 122. By way of example in which the feature is color, different colors may represent different numbers of 3D object formation cycles. In examples in which the feature is the pattern of the fiduciary object 130, different patterns, such as different geometrical shapes, different numbers, or the like, may represent the different numbers of 3D object formation cycles. In some examples, the feature may be a combination of different physical features, e.g., texture and color, etc.

[0021] The processor 102 may fetch, decode, and execute the instructions 1 16 to control a supply device 124 to supply a fiduciary object 130 having the identified feature among the build material particles 122. Particularly, and as shown in FIG. 1 B, the processor 102 may control the supply device 124 to supply the fiduciary object 130 among the build material particles 122 following application of the build material particles 122 into a layer 138 during a 3D object formation operation. That is, the fiduciary object 130 may be supplied into the build material particles 122 during formation of a 3D object from the build material particles 122. Particularly, the fiduciary object 130 may be formed from build material particles 122 positioned at a location away from build material particles 122 that are formed into a section 132 of the 3D object. That is, the fiduciary object 130 may be formed during a processing operation that includes the formation of a section 132 of the 3D object. In any regard, the feature of the fiduciary object 130 may correspond to the age of the build material particles 122, which may be the number of previously applied 3D object formation cycles plus the current 3D object formation cycle. [0022] As shown in FIG. 1 B, during fabrication of the 3D object, the build material particles 122 may be provided on a build platform 134 in multiple layers 136, 138. In layer 136, a section 140 of the 3D object is depicted as having been formed through fusing of the build material particles 122 in that section 140, for instance, through application of heat from a heating mechanism 126. In addition, the build material particles 122 in the section 132 are depicted as undergoing a fusing process to thus fuse the section 132 with the section 140. That is, an agent may have been applied onto the build material particles 122 in the section 132 and the heating mechanism 126 may apply heat onto the layer 138 of build material particles 122 to melt the build material particles 122 in the section 132. This process may be repeated on subsequent layers and sections to form the 3D object. As also shown, the fiduciary object 130 may be formed from build material particles 122 in the layer 138 in similar manners, although it is contemplated that the fiduciary object 130 may also be formed from build material particles 122 in multiple layers 136, 138.

[0023] According to examples, the agent may be a fusing agent that may enhance absorption of heat from the heating mechanism 126 to heat the build material particles 122 to a temperature that is sufficient to cause the build material particles 122 upon which the agent has been deposited to melt. In addition, the heating mechanism 126 may apply heat, e.g., in the form of heat and/or light, at a level that causes the build material particles 122 upon which the agent has been applied to melt without causing the build material particles 122 upon which the agent has not been applied to melt. The agent may also deposited on the build material particles 122 located in the position of the layer 138 at which the fiduciary object 130 is to be formed. Thus, for instance, the fiduciary object 130 may be formed through melting during application of heat from the heating mechanism 126 on the layer 138 and subsequent cooling and hardening.

[0024] The supply device 124 may supply multiple types of agents onto the layers 136, 138 of build material particles 122. The multiple types of agents may include agents having different properties with respect to each other to thus cause the fiduciary object 130 to have different features depending upon the agent or agents that are deposited onto the build material particles 122 forming the fiduciary object 130. In this regard, the processor 102 may control the supply device 124 to supply the agent or a combination of agents that results in the fiduciary object 130 having the identified feature that is based upon the age of the batch 120 of build material particles 122. By way of particular example, the multiple types of agents may be different colored inks and the processor 102 may control the supply device to deposit an agent or a combination of agents onto build material particles 122 to form a fiduciary object 130 having a particular color from those build material particles 122.

[0025] In addition or in other examples, the supply device 124 may contain pre-fabricated fiduciary objects 130 having different properties, e.g., different colors, different textures, different shapes, etc. In these examples, the processor 102 may identify which of the fiduciary objects 130 contained in the supply device 124 is to be interspersed with the build material particles 122. In addition, the processor 102 may control the supply device 124 to deliver a fiduciary object 130 having the identified feature to be interspersed with the build material particles 122.

[0026] In the examples above, the fiduciary object 130 may be supplied, e.g., formed from, deposited onto, or the like, among the build material particles 122 that are located in an area that is outside of the build material particles 122 that are fused together to form the 3D object, e.g. , outside of the sections 132, 140. In one regard, therefore, the fiduciary object 130 may remain with build material particles 122 that are unused to form the 3D object. As also shown in FIG. 1 B, a collection mechanism 142 may be provided to reclaim the unused build material particles 122 following fabrication of the 3D object from the build material particles 122 that have been fused to form the sections 132, 140. The collection mechanism 142 may include a vacuum or other suction device that may remove the unused build material particles 122 from the formed 3D object and to store the removed build material particles 122 in a reclaimed material hopper 144. As discussed herein, the build material particles 122 in the reclaimed material hopper 144 may be re-used and/or stored for future re-use. In addition, although the collection mechanism 142 has been depicted as being located beneath the build platform 134, it should be understood that the collection mechanism 142 may be positioned above the build platform 134 and may also be movable with respect to the build platform 134.

[0027] According to examples, the fiduciary object 130 may be formed to occupy a sufficiently small volume such that the fiduciary object 130 is reclaimed with the unused build material particles 122. That is, in instances in which the collection mechanism 142 includes a screen through which the reclaimed build material particles 122 are filtered, the fiduciary object 130 may be of a sufficiently small volume to pass through openings in the screen such that the fiduciary object 130 may remain interspersed with the build material particles 122 in the reclaimed material hopper 144. In addition, the fiduciary object 130 may be formed to have a sufficiently large volume to be identified and distinguished from the build material particles 122 with the naked eye. Thus, for instance, the age, e.g., the number of 3D object formation cycles that the build material particles 122 in the reclaimed material hopper 144 have undergone, may be determined from a visual inspection of the fiduciary object 130 contained in the reclaimed material hopper 144.

[0028] Although particular reference is made herein to a single fiduciary object 130 being supplied among the build material particles 122, it should be understood that multiple fiduciary objects 130 may be supplied without departing from scopes of the present disclosure. In one regard, multiple fiduciary objects 130 may be supplied among the build material particles 122 in order to enable a fiduciary object 130 to more readily be located. In another regard, the reclaimed build material particles 122 may be separated into multiple bins and thus, having multiple fiduciary objects 130 interspersed among the build material particles 122 may increase the likelihood that a fiduciary object 130 will be interspersed in each of the multiple bins.

[0029] According to examples, the processor 102 may also determine the number of fiduciary objects 130 that are to be supplied during a 3D object formation cycle. The number of fiduciary objects 130 to be introduced may be based upon, for instance, the amount of build material particles 122, the number of layers, or the like, that is to be used to form the 3D object. For instance, the processor 102 may determine that a larger number of fiduciary objects 130 are to be supplied when a greater amount of build material particles 122 are to be used. In any regard, the processor 102 may supply the determined number of fiduciary objects 130 among the build material particles 122 during the 3D object formation cycle.

[0030] With reference now to FIG. 2, there is shown a block diagram of an example 3D printer 200. It should be understood that the 3D printer 200 depicted in FIG. 2 may include additional components and that some of the components described herein may be removed and/or modified without departing from a scope of the 3D printer disclosed herein. The description of FIG. 2 is made with reference to the elements shown in FIGS. 1 A and 1 B.

[0031] The 3D printer 200 may include a build chamber 202 within which a 3D object 204 may be fabricated from build material particles 122 provided in respective layers in a build bucket 206. Particularly, a movable build platform 208 may be provided in the build bucket 206 and may be moved downward as the 3D object 204 is formed in successive layers of the build material particles 122. An upper hopper 212, which may also include a cyclone separator, may supply a spreader 210 with the build material particles 122 and the spreader 210 may move across the build bucket 206 to form the successive layers of build material particles 122. In addition, forming components 214 may be implemented to deliver an agent onto selected locations on the layers of build material particles 122 to form sections of the 3D object 204 in the successive layers. The forming components 214 may include an agent delivery device or multiple agent delivery devices, e.g., the supply device 124. Thus, although the forming components 214 have been depicted as a single element, it should be understood that the forming components 214 may represent multiple elements. A heating mechanism 126 to apply heat onto the layers of build material particles 122 to form the sections of the 3D object 204 may also be provided in the build chamber 202.

[0032] The 3D printer 200 may include the apparatus 100 discussed above with respect to FIGS. 1A and 1 B. The apparatus 100 may include a processor 102 that may control various operations in the 3D printer 200, including the spreader 210, the hopper 212, and the forming components 214. In addition, the processor 102 may control the supply of a fiduciary object 130 among the build material particles 122 in the build bucket 206. The processor 102 may implement the operations discussed above to identify a feature of the fiduciary object 130 based upon the age of the build material particles 122 and to supply the fiduciary object 130 having the identified feature among the build material particles 122. That is, for instance, the processor 102 may control the forming components 214 to form the 3D object 204 and the fiduciary object 130 in a volume of build material particles 122 contained in the build basket 206. In addition, the fiduciary object 130 may be formed in a location that is outside of the 3D object 204 so as to be separate from the 3D object 204.

[0033] The build material particles 122 used to form the 3D object 204 may be composed of build material particles from a fresh supply 220 of build material particles, build material particles from a recycled supply 222 of build material particles, or a mixture thereof. The fresh supply 220 may represent a removable container that contains build material particles that have not undergone any 3D object formation cycles. The recycled supply 222 may represent a removable container that contains build material particles that have undergone at least one 3D object formation cycle and may contain build material particles that have undergone different numbers of 3D object formation cycles with respect to each other. As shown, the build material particles in the fresh supply 220 may be provided into a fresh material hopper 224 and the build material particles in the recycled supply 222 may be provided into a recycled material hopper 226. Additionally, the build material particles in either or both of the fresh material hopper 224 and the recycled material hopper 226 may be supplied to the upper hopper 212. The build material particles may be provided into the hoppers 224, 226 from the respective supplies 220, 222 prior to implementing a print job to ensure that there are sufficient build material particles to complete the print job.

[0034] Generally speaking, the processor 102 may control the mixture or ratio of the fresh build material particles and recycled build material particles that are supplied to the upper hopper 212. The ratio may depend upon the type of 3D object 204 being formed. For instance, a higher fresh build material particle to recycled build material particle ratio, e.g., up to a 100 percent fresh build material particle composition, may be supplied when the 3D object 204 is to have a higher quality, to have thinner sections, have higher tolerance requirements, or the like. Conversely, a lower fresh build material particle to recycled build material particle ratio, e.g., up to a 100 percent recycled build material particle composition, may be supplied when the 3D object 204 is to have a lower quality as may occur when the 3D object 204 is a test piece or a non-production piece, when the 3D object 204 is have lower tolerance requirements, or the like. The ratio may be user-defined, may be based upon a particular print job, may be based upon a print setting of the 3D printer 200, and/or the like.

[0035] In any regard, the processor 102 may control the ratio of the fresh and the recycled build material particles supplied to the upper hopper 212 through control of respective feeders 228, 230. A first feeder 228 may be positioned along a supply line from the fresh material hopper 224 and a second feeder 230 may be positioned along a supply line from the recycled material hopper 226. The first feeder 228 and the second feeder 230 may be rotary airlocks that may regulate the flow of the build material particles from the respective hoppers 224, 226 along a feed line 232 toward the upper hopper 212. The feed line 232 may also be supplied with air from an input device 234 to assist in the flow of build material particles from the hoppers 224, 226 to the upper hopper 212.

[0036] A third feeder 236, which may also be a rotary airlock, may be positioned along a supply line from the upper hopper 212 to the spreader 210. The upper hopper 212 may include a level sensor (not shown) that may detect the level of build material particles contained in the upper hopper 212. The processor 102 may determine the level of the build material particles contained in the upper hopper 212 from the detected level and may control the feeders 228, 230 to supply additional build material particles in a particular ratio when the processor 102 determines that the build material particle level in the upper hopper 212 is below a threshold level, e.g., to ensure that there is a sufficient amount of build material particles to form a layer of build material particles having a certain thickness during a next spreader 210 pass. [0037] The 3D printer 200 may also include the collection mechanism 142 discussed above with respect to FIG. 1 B. The collection mechanism 142 may include a blow box 240, a filter 242, a sieve 244, and a reclaimed material hopper 246. Airflow through the collection mechanism 142 may be provided by a collection blower 248. The collection mechanism 142 may reclaim unused build material particles 122 from the build bucket 206 as well as from a location adjacent to the build bucket 206 as shown in FIG. 2. Particularly, as discussed above, following formation of the 3D object 204, the build material particles 122 may remain in powder form and the collection mechanism 142 may reclaim the build material particles 122 that were not formed into the 3D object 204. The collection mechanism 142 may also collect the fiduciary object 130 during collection of the unused build material particles 122. That is, the unused build material particles 122 and the fiduciary object 130 may be separated from the 3D object 204 through application of a vacuum force inside the build bucket 206. The collection mechanism 142 may also be vibrated to separate the unused build material particles 122 from the 3D object 204.

[0038] The unused build material particles 122 and the fiduciary object 130 in the build bucket 206 may be sucked into the blow box 240 and through the filter 242 and the sieve 244 before being collected in the reclaimed material hopper 246. The fiduciary object 130 may thus be of a sufficiently small size to pass through the filter 242 and the sieve 244, but may also be of a sufficiently large size to be visible. By way of particular example, the fiduciary object 130 may have dimensions that may range from about 20 μιη to about 30 μιη. Additionally, during spreading of the build material particles 122 to form layers on the build bucket 206, e.g., as the spreader 210 moves across the build bucket 206, excess build material particles 122 may collect around a perimeter of the build bucket 206. As shown, a perimeter vacuum 216 may be provided to collect the excess build material particles 122, such that the collected build material particles 122 may be supplied to the collection mechanism 142. A valve 250, such as an electronically controllable three-way valve, may be provided along a feed line 252 from the build bucket 206 and the perimeter vacuum 216. In examples, the processor 102 may manipulate the valve 250 such that particles flow from the perimeter vacuum 216 during formation of the 3D object 204 and flow from the build bucket 206 following formation of the 3D object 204.

[0039] A fourth feeder 254, which may also be a rotary airlock, may be provided to feed the reclaimed build material particles 256 contained in the reclaimed material hopper 246 to the upper hopper 212 and/or to a lower hopper 258. As shown in FIG. 2, the fourth feeder 254 may feed the reclaimed build material particles 256 through the feed line 232. A valve 260, such as an electronic three-way valve, may be provided along the feed line 232 and may direct the reclaimed build material particles 256 to the upper hopper 212 or may divert the reclaimed build material particles 256 to the lower hopper 258. The processor 102 may also manipulate the valve 260 to control whether the reclaimed build material particles 256 are supplied to the upper hopper 212 or the lower hopper 258. As discussed above, the processor 102 may make this determination based upon the ratio of fresh and recycled build material particles that is to be used to form the 3D object 204.

[0040] A fifth feeder 262, which may also be a rotary airlock, may be provided to feed the reclaimed build material particles 256 contained in the lower hopper 258 to the recycled supply 222 and/or the recycled material hopper 226. The processor 102 may control the fifth feeder 262 to feed the reclaimed build material particles 256 into the recycled supply 222 in instances in which the reclaimed build material particles 256 are not to be used in a current build. In addition, the processor 102 may control the fifth feeder 262 to feed the reclaimed build material particles 256 into the recycled material hopper 226 in instances in which the reclaimed build material particles 256 are to be used in a current build.

[0041] As discussed above, a fiduciary object 130 may be included among the reclaimed build material particles 256. In this regard, the fiduciary object 130 may be supplied to the lower hopper 258 and then to the recycled supply 222 or the recycled material hopper 226. The fiduciary object 130 may thus remain with the reclaimed build material particles 256 in the recycled supply 222 or the recycled material hopper 226. For instance, the fiduciary object 130 may remain in the recycled supply 222 in instances in which the recycled supply 222 is removed from the 3D printer 200, for instance, for storage and/or use in another 3D printer. The fiduciary object 130 may therefore identify the age of the build material particles contained in the recycled supply 222.

[0042] The fiduciary object 130 may be removed from the reclaimed build material particles 256 prior to the reclaimed build material particles 256 being supplied to the upper hopper 212. That is, a filter 264 may be provided along the feed line 232 upstream of the upper hopper 212, in which the filter 264 has openings that may enable the build material particles 256 to pass through but may be too small for the fiduciary object 130 to pass through. The fiduciary object 130 may be removed from the filter 264 and the filtered build material particles 256 may be supplied into the upper hopper 212.

[0043] According to examples, the 3D printer 200 may include a detector 266 that may detect a feature of the fiduciary object 130 and may communicate the detected feature information to the processor 102. By way of example, the detector 266 may be a photodetector and may capture an image of the fiduciary object 130, which the detector 266 may communicate to the processor 102. The processor 102 may determine the number of 3D object forming cycles that the build material particles 122 have been subjected from which the fiduciary object 130 was removed based upon the detected feature. That is, for instance, the processor 102 may determine from a look-up table, a chart, a database, or the like, a correspondence between the detected feature and the number of 3D object forming cycles. In other examples, an operator may visually examine the fiduciary object 130 to determine the feature of the fiduciary object 130 and may determine the age of the build material particles 122 from the visual inspection. The processor 102 may identify a next feature corresponding to the next 3D object forming cycle and may supply a fiduciary object 130 having the next feature during the next 3D object forming cycle.

[0044] The 3D printer 200 may also include a filter blower 270 that may create suction to enhance airflow through the lines in the 3D printer 200. The airflow may flow through a filter box 272 and a filter 274 that may remove particulates from the airflow from the upper hopper 212 and the lower hopper 258 prior to the airflow being exhausted from the 3D printer 200. In other words, the filter blower 270, filter box 272, and filter 274 may represent parts of the outlets of the cyclone powder traps of the upper and lower hoppers 212 and 258 and may collect particulates from the airflow in the upper and lower hoppers 212 and 258.

[0045] Although not shown in FIG. 2, the apparatus 100 may also include an interface through which the processor 102 may communicate instructions to a plurality of components contained in the 3D printer 200. The interface may be any suitable hardware and/or software through which the processor 102 may communicate the instructions. In any regard, the processor 102 may communicate with the components of the 3D printer 200 as discussed above.

[0046] Various manners in which the apparatus 100 and the 3D printer 200 may be implemented are discussed in greater detail with respect to the method 300 depicted in FIG. 3. Particularly, FIG. 3 depicts an example method 300 for introducing an item having a feature that indicates an estimated number of 3D object formation cycles to which build material particles have been subjected. It should be apparent to those of ordinary skill in the art that the method 300 may represent a generalized illustration and that other operations may be added or existing operations may be removed, modified, or rearranged without departing from a scope of the method 300.

[0047] The description of the method 300 is made with reference to the apparatus 100 and the 3D printer 200 illustrated in FIGS. 1A, 1 B, and 2 for purposes of illustration. It should be understood that apparatuses and 3D printers having other configurations may be implemented to perform the method 300 without departing from a scope of the method 300.

[0048] At block 302, the processor 102 may execute the instructions 1 12 to compute an estimated number of 3D object formation cycles to which build material particles 122 have been subjected. Each 3D object formation cycle may include a cycle in which some or all of the build material particles 122 are applied onto a build platform 208 and a 3D object 204 is formed from some of the build material particles 122 on the build platform 208 and some or all of the build material particles 122 that are not used to form the 3D object 204 are recycled. The number of 3D object formation cycles may thus be the number of times that the unused build material particles 122 have been recycled.

[0049] The number of 3D object formation cycles may be an estimated number as the build material particles 122 used to form a 3D object 204 may include build material particles 122 that have undergone different numbers of 3D object formation cycles with respect to each other. For instance, not all of the build material particles 122 may be used in each build process. In addition, the recycled build material particles 122 in the recycled supply 222 may be reclaimed from different build processes an may thus have undergone or been subjected to different numbers of 3D object formation cycles with respect to each other.

[0050] In any regard, a fiduciary object 130 may have been supplied among each of the reclaimed build material particles 122, in which each of the fiduciary objects 130 may include a respective feature corresponding to the number of 3D object formation cycles that the reclaimed build material particles 122 have been subjected. The ages, e.g., the numbers of times the reclaimed build material particles 122 have been subjected, may be determined from the features of the fiduciary object 130. In instances in which the recycled supply 222 contains multiple fiduciary objects 130 denoting different ages, the processor 102 may determine the estimated age of the build material particles 122 to be equivalent to the age of the oldest build material particles 122.

[0051] In some examples, the processor 102 may compute the estimated age of the build material particles 122 based upon probabilities of finding the fiduciary objects 130 having certain features in the recycled build material particles and a density at which the fiduciary objects 130 are packed in the recycled build material particles. For instance, the processor 102 may implement heuristics to computing the estimated age from the multiple fiduciary objects 130 having different features with respect to each other.

[0052] At block 304, the processor 102 may execute the instructions 1 14 to identify a feature for an item 130 that is based upon the estimated number of 3D object formation cycles to which the build material particles 122 have been subjected. The item 130 may be equivalent to the fiduciary object 130 discussed herein and may thus be a visual indicator of the estimated age of the build material particles 122. The age of the build material particles 122 may be the number of previous 3D object formation cycles that the build material particles 122 are estimated to have been subjected plus the current 3D object formation cycle. In addition, the feature may be a physical feature or characteristic such as color, texture, shape, pattern, or the like.

[0053] At block 306, the processor 102 may execute the instructions 1 16 to introduce an item 130 having the identified feature among the build material particles 122. Particularly, the item 130 may be introduced among the build material particles 122 after the build material particles 122 have been formed into a layer on a build platform 134, 208. In addition, the item 130 may be introduced among the build material particles 122 in a location outside of the build material particles 122 used to form a 3D object 204 any of the manners discussed above. As also discussed above, following formation of the 3D object 204, the build material particles 256 that are not used to form the 3D object 204 and the item 130 may be reclaimed, for instance, by the collection mechanism 142. In addition, the reclaimed build material particles 256 and the item 130 may be supplied from the collection mechanism 142 to the recycled supply 222 for possible storage and/or reuse.

[0054] Turning now to FIG. 4, there is shown a flow diagram of an example method 400 for introducing items 130 among build material particles 122. The description of the method 400 is made with reference to the 3D printer 200 depicted in FIG. 2.

[0055] At block 402, the processor 102 may determine a ratio of fresh build material particles and recycled build material particles that is supplied to the upper hopper 212. The ratio may be user-defined, may be based upon a particular print job, may be based upon a print setting of the 3D printer 200, and/or the like. At block 404, the fresh and/or the recycled build material particles may be supplied and mixed through a feed line 232 directed toward the upper hopper 212. At block 406, prior to reaching the upper hopper 212, a plurality of items 130 may be removed from the recycled build material particles, e.g. , by the filter 264. That is, the recycled build material particles from the recycled supply 222 may include reclaimed build material particles 256 that have undergone different numbers of 3D object formation cycles with respect to each other and may include respective items 130 that correspond to the different ages.

[0056] At block 408, the processor 102 may compute an estimated number of 3D object formation cycles to which the mixed build material particles have been subjected based upon probabilities of finding the items 130 having certain features in the recycled build material particles and a density at which the items 130 are packed in the recycled build material particles. For instance, the processor 102 may implement heuristics to compute the estimated number of 3D object formation cycles to which the mixed build material particles have been subjected from the multiple fiduciary objects 130 having different features with respect to each other. In a particular example, the processor 102 may identify the item 130 that corresponds to the oldest, e.g., the most 3D object formation cycles, and may compute the estimated number of 3D object formation cycles to be equivalent to the number corresponding to that item 130.

[0057] At block 410, the processor 102 may identify a current feature for a current item 130. The current feature may be the feature that corresponds to the next number of 3D object formation cycles. At block 412, the processor 102 may determine a number of current items 130 that are to be introduced during the current build cycle. The processor 102 may determine the number of fiduciary objects 130 to be introduced based upon, for instance, the amount of build material particles 122, the number of layers, or the like, that is to be used to form the 3D object. At block 414, the processor 102 may introduce the determined number of current items 130 having the identified current feature among the build material particles, e.g., during formation of a 3D object 204.

[0058] Some or all of the operations set forth in the methods 300 and 400 may be contained as utilities, programs, or subprograms, in any desired computer accessible medium. In addition, some or all of the operations set forth in the methods 300 and 400 may be embodied by computer programs, which may exist in a variety of forms both active and inactive. For example, they may exist as machine 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.

[0059] Although described specifically throughout the entirety of the instant disclosure, representative examples of the present disclosure have utility over a wide range of applications, and the above discussion is not intended and should not be construed to be limiting, but is offered as an illustrative discussion of aspects of the disclosure.

[0060] What has been described and illustrated herein is an example of the disclosure along with some of its variations. The terms, descriptions and figures used herein are set forth by way of illustration only and are not meant as limitations. Many variations are possible within the spirit and scope of the disclosure, which is intended to be defined by the following claims - and their equivalents - in which all terms are meant in their broadest reasonable sense unless otherwise indicated.

Claims

What is claimed is:

1 . An apparatus comprising:

a processor;

a memory on which is stored machine readable instructions that are to cause the processor to:

determine a number of 3D object formation cycles that a batch of build material particles has undergone;

identify a feature for a fiduciary object to be supplied among the build material particles, wherein the feature is based upon to the determined number of 3D object formation cycles; and

control a supply device to supply a fiduciary object having the identified feature among the build material particles.

2. The apparatus according to claim 1 , further comprising:

forming components; and

wherein to introduce the fiduciary object, the instructions are further to cause the processor to control the forming components to form the fiduciary object from some of the plurality of build material particles.

3. The apparatus according to claim 2, wherein the instructions are further to cause the processor to control the forming components to form a three-dimensional (3D) object in a volume of the build material particles and to form the fiduciary object in an area outside of a build area of the 3D object in the volume of the build material particles.

4. The apparatus according to claim 3, further comprising:

a collection mechanism to reclaim build material particles from the volume of build material particles that are outside of the build area of the 3D object and to reclaim the fiduciary object and to feed the reclaimed build material particles and the fiduciary object into a reclaimed material hopper.

5. The apparatus according to claim 4, further comprising:

a heating mechanism to heat the build material particles during formation of the 3D object;

a filter mechanism to filter the reclaimed build material particles to remove the fiduciary object from the reclaimed build material particles; and

wherein the instructions are further to cause the processor to re-use the reclaimed build material particles in a subsequent 3D object build process after the fiduciary object has been filtered from the reclaimed build material particles.

6. The apparatus according to claim 2, wherein the instructions are further to cause the processor to:

receive an instruction to form a 3D object;

determine an amount of fresh build material particles and an amount of recycled build material particles to be used to form the 3D object, wherein the recycled build material particles include the fiduciary object;

supply and mix the determined amount of fresh build material particles and the determined amount of recycled build material particles through a feed line; filter the fiduciary object from the recycled build material particles;

form the 3D object using the mixed build material particles; and introduce another fiduciary object having another feature that corresponds to a next number of 3D object formation cycles.

7. The apparatus according to claim 1 , wherein the instructions are further to cause the processor to:

receive an instruction to form a 3D object;

determine an amount of fresh build material particles and an amount of recycled build material particles to be used to form the 3D object, wherein the recycled build material particles include a plurality of fiduciary objects having different features with respect to each other;

supply and mix the determined amount of fresh build material particles and the determined amount of recycled build material particles;

remove the plurality of fiduciary objects from the recycled build material particles; and

compute an estimated number of 3D object formation cycles that the mixed build material particles have undergone based upon probabilities of finding the fiduciary objects having certain features in the mixed build material particles and a density at which the fiduciary objects are packed in the recycled build material particles.

8. The apparatus according to claim 7, wherein the instructions are further to cause the processor to:

identify a current feature for a current fiduciary object to be introduced during formation of the 3D object, wherein the current feature is based upon the estimated number of 3D object formation cycles that the mixed build material particles have undergone;

determine a number of current fiduciary objects to be supplied during formation of the 3D object; and

supply the determined number of current fiduciary objects having the identified current characteristic.

9. The apparatus according to claim 1 , further comprising:

a supply device containing a plurality of fiduciary objects having different features with respect to each other; and

wherein to introduce the fiduciary object, the instructions are further to cause the processor to control the supply device to introduce the fiduciary object having the identified characteristic from the plurality of fiduciary objects among the build material particles.

10. A method comprising:

computing, by a processor, an estimated number of 3D object formation cycles to which build material particles have been subjected;

identifying, by the processor, a feature for an item that is based upon the estimated number of 3D object formation cycles to which the build material particles have been subjected; and introducing, by the processor, an item having the identified feature among the build material particles during a build process of a three-dimensional (3D) object from the build material particles.

1 1 . The method according to claim 10, wherein introducing the item further comprises forming the item in build material particles that are outside of the build material particles used to form the 3D object.

12. The method according to claim 1 1 , further comprising:

reclaiming the build material particles that are not used to form the 3D object and the item; and

storing the reclaimed build material particles and the item in a recycled supply.

13. The method according to claim 10, further comprising

determining an amount of fresh build material particles and an amount of recycled build material particles to be used to form the 3D object, wherein the recycled build material particles include a plurality of items having different features with respect to each other;

supplying and mixing the determined amount of fresh build material particles and the determined amount of recycled build material particles through a feed line;

removing the plurality of items from the mixed build material particles; computing an estimated number of 3D object formation cycles to which the mixed build material particles have been subjected based upon probabilities of finding the items having certain features in the mixed build material particles and a density at which the items are packed in the recycled build material particles; identifying a current feature for a current item to be introduced during formation of the 3D object, wherein the current feature is based upon the estimated number of heating cycles to which the mixed build material particles have been subjected;

determining a number of current items to be introduced during formation of the 3D object; and

introducing the determined number of current items having the identified current feature.

14. A printing system comprising:

a build platform;

forming components; and

a processor to control the forming components to form a three-dimensional (3D) object and a fiduciary object from build material particles placed on the build platform, wherein the fiduciary object includes a feature that is based upon an estimated number of 3D object forming cycles to which the build material particles have been subjected.

15. The printing system according to claim 14, further comprising:

a collection mechanism to reclaim the build material particles outside of the 3D object and the fiduciary object from the 3D object and to store the reclaimed build material particles and the fiduciary object in a hopper.