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WO2020046361A1 - Séparation d'objets imprimés - Google Patents

Séparation d'objets imprimés Download PDF

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Publication number
WO2020046361A1
WO2020046361A1 PCT/US2018/049040 US2018049040W WO2020046361A1 WO 2020046361 A1 WO2020046361 A1 WO 2020046361A1 US 2018049040 W US2018049040 W US 2018049040W WO 2020046361 A1 WO2020046361 A1 WO 2020046361A1
Authority
WO
WIPO (PCT)
Prior art keywords
platform
separator
build
build platform
powder
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/US2018/049040
Other languages
English (en)
Inventor
Pedro Ros Zuazua
Joaquim BRUGUE GARVI
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Hewlett Packard Development Co LP
Original Assignee
Hewlett Packard Development Co LP
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Hewlett Packard Development Co LP filed Critical Hewlett Packard Development Co LP
Priority to PCT/US2018/049040 priority Critical patent/WO2020046361A1/fr
Publication of WO2020046361A1 publication Critical patent/WO2020046361A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

Links

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
    • B22F12/30—Platforms or substrates
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F12/00—Apparatus or devices specially adapted for additive manufacturing; Auxiliary means for additive manufacturing; Combinations of additive manufacturing apparatus or devices with other processing apparatus or devices
    • B22F12/22—Driving means
    • B22F12/222—Driving means for motion along a direction orthogonal to the plane of a layer
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/10—Processes of additive manufacturing
    • B29C64/141—Processes of additive manufacturing using only solid materials
    • B29C64/153—Processes of additive manufacturing using only solid materials using layers of powder being selectively joined, e.g. by selective laser sintering or melting
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/30—Auxiliary operations or equipment
    • B29C64/35—Cleaning
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
    • B29C—SHAPING OR JOINING OF PLASTICS; SHAPING OF MATERIAL IN A PLASTIC STATE, NOT OTHERWISE PROVIDED FOR; AFTER-TREATMENT OF THE SHAPED PRODUCTS, e.g. REPAIRING
    • B29C64/00—Additive manufacturing, i.e. manufacturing of three-dimensional [3D] objects by additive deposition, additive agglomeration or additive layering, e.g. by 3D printing, stereolithography or selective laser sintering
    • B29C64/30—Auxiliary operations or equipment
    • B29C64/379—Handling of additively manufactured objects, e.g. using robots
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y30/00—Apparatus for additive manufacturing; Details thereof or accessories therefor
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B33—ADDITIVE MANUFACTURING TECHNOLOGY
    • B33Y—ADDITIVE MANUFACTURING, i.e. MANUFACTURING OF THREE-DIMENSIONAL [3-D] OBJECTS BY ADDITIVE DEPOSITION, ADDITIVE AGGLOMERATION OR ADDITIVE LAYERING, e.g. BY 3-D PRINTING, STEREOLITHOGRAPHY OR SELECTIVE LASER SINTERING
    • B33Y40/00—Auxiliary operations or equipment, e.g. for material handling
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/20—Direct sintering or melting
    • B22F10/28—Powder bed fusion, e.g. selective laser melting [SLM] or electron beam melting [EBM]
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B22—CASTING; POWDER METALLURGY
    • B22F—WORKING METALLIC POWDER; MANUFACTURE OF ARTICLES FROM METALLIC POWDER; MAKING METALLIC POWDER; APPARATUS OR DEVICES SPECIALLY ADAPTED FOR METALLIC POWDER
    • B22F10/00—Additive manufacturing of workpieces or articles from metallic powder
    • B22F10/70—Recycling
    • B22F10/73—Recycling of powder
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
    • Y02P10/00—Technologies related to metal processing
    • Y02P10/25—Process efficiency

Definitions

  • Additive manufacturing technologies such as three-dimensional printers, allow objects or parts to be built by, for example, through selective solidification of portions of layers of powder or powder-like build material (comprised of plastic, ceramic, or metal for example) to form a series of cross-sections.
  • the cross- sections join or fuse together to create the object on a layer-by-layer basis.
  • the object, once printed, is extracted from a surrounding powder matrix to separate the object from the powder.
  • Figure 2 shows a method for separation of a rendered object from bulk powder according to an example.
  • a separator platform having apertures for example a mesh or apertured plate, is arranged upon a build platform onto which an object is to be generated.
  • the separator platform allows powder or build material to pass through it.
  • the separator platform allows bulk powder to pass through it.
  • Resilient elements support the build platform which are attached to ejector rods which in turn support the separator platform independently of the build platform.
  • the resilient elements are compressible.
  • a drive unit may be positioned below the build platform, which is configured by a control unit, to raise or lower the build platform thereby to separate the object on the separator platform from bulk powder.
  • a separator platform is provided upon a build platform onto which a three-dimensional object or objects are generated. Some initial layers of build material in which no material is solidified may be formed onto the separator platform, onto which the object is generated.
  • the build platform and separator platform may be raised to the highest position in the apparatus. The build platform and separator platform can be lowered together during generation of the object to allow each layer of build material to be formed and selectively solidified. After the object is completed, the build platform and separator platform may then be separated. For example, the separator platform may be raised by the ejector rods.
  • the build platform may be lowered whilst the ejector rods maintain the separator platform in the same position.
  • the ejector rods separate the separator platform from the build platform.
  • the separator platform is arranged to hold a rendered object whilst allowing the bulk powder to pass through and thus separating the object from the bulk powder. As the build platform is separated from the separator platform, excess powder surrounding the rendered object falls through the separator platform to separate the object from the powder matrix. The object can then be easily removed.
  • Figures 1 A-E show an apparatus or extraction device 100 for separating a three-dimensional rendered object 101 from bulk powder 102 according to an example.
  • the apparatus comprises a build platform 103 and a separator platform 104.
  • the separator platform 104 is arranged upon the build platform 103 and an object 101 can be generated onto the separator platform.
  • the separator platform may be a sieve or open grid.
  • the separator platform is vertically movable independent of the build platform by means of a support unit, and initially the separator platform is positioned upon the build platform.
  • the support unit is positioned below the build platform.
  • the support unit comprises ejector rods or pins 106 and a support layer 108.
  • the support unit may comprise resilient elements 1 10, such as springs for example.
  • the ejector rods 106 may be guided on the build platform and may extend under the build platform.
  • the ejector rods may contact the support layer 108..
  • the ejector rods 106 can support the separator platform 104 independently of the build platform 103.
  • the resilient elements 110 extend under the build platform 103 and contact the support layer 108.
  • a control unit is configured to drive the drive unit to raise or lower the build platform.
  • the drive unit may comprise, for example, a motor 1 12, nut 1 14 and leadscrew 1 16 or vertical transmission structure.
  • the drive unit may be positioned below the build platform.
  • the build platform can be attached to the drive unit via an attachment portion 103a.
  • the build platform 103 and the separator platform 104 are positioned together, as shown in Figure 1A.
  • Powder layers 102 are deposited on the build platform 103 and are selectively solidified to additively manufacture the object 101 .
  • the build platform 103 is translated or moved, for example vertically downwards, or the separator platform is raised, in order to separate the build platform from the separator platform, until the resilient elements 1 10 are compressed adjacent the support layer 108 ( Figures 1A-C). Due to the selective solidification process, the object will be surrounded, and possibly covered, by non-solidified powder.
  • the separator platform 104 and powder atop the build platform are also lowered. Once the separator platform 104 reaches a level such that the ejector rods 106 contact the support layer 108, as shown in Figure 1 C, the ejector rods support the separator platform and the object 101 thereby holding the separator platform 104. As the build platform 103 is lowered, the separator platform 104 is separated from the build platform 103.
  • the build platform 103 may comprise a flat surface.
  • the space below the build platform is void of powder material and comprises the resilient elements 1 10, support unit 108 and drive unit.
  • the powder is sieved through the separator platform with the aid of gravity.
  • the build platform may be vertically shaken or oscillated as it descends (by way of the drive unit), thereby aiding the sieving of the powder through the separator platform to promote separation of the object from the powder matrix.
  • a shaker unit may be integrated into any of the elements of the apparatus.
  • the control unit is configured to control the drive unit to raise and/or lower the build platform in an oscillatory manner.
  • control unit may be configured to oscillate the build platform at an oscillation frequency selected according to powder properties, such as powder material type (plastic or metal) and/or a particle size or range of particle sizes of the powder.
  • control unit may be configured to cause the drive unit to oscillate the build platform at an oscillation frequency selected according to a humidity level of the environment in which the object is rendered, or a humidity level of the powder, or both. Accordingly, once the build platform has been fully lowered the object may rest on the top of separator platform. The object may then be easily removed from the apparatus. According to an example, the separator platform is removable allowing easier access to the remaining powder. The non-solidified powder may be recycled.
  • an oscillation frequency may be relatively higher for a relatively smaller particle size compared to the frequency selected for a relatively larger particle size.
  • the frequency may be within the range 10-1000Hz for a relatively smaller particle size, such as 1 -60pm.
  • the frequency may be within the range 1-10Hz for a relatively larger particle size, such as 100- 1000pm, for example.
  • the amplitude of oscillation may be modified depending on particle and/or environmental parameters. For example, relatively higher humidity levels may call for an increased amplitude of oscillation and so on.
  • a shaker unit may be attached to the support unit or to the build platform to improve object separation by shaking the support unit or build platform.
  • the shaker unit can be used to provide lateral (direction arrow B) shaking of the separator platform and/or build platform, which can be provided in addition to the vertical oscillation described above. This can aid the flow of powder through the separator platform and from the object itself since any agglomeration of powder is disturbed or broken apart.
  • the build platform may be raised and lowered for a number of cycles to aid separation of the object and/or separator platform from the bulk powder.
  • the separator platform can be raised through the powder bed which raises the object out of the powder bed to enable easy recovery of the object.
  • Figure 1 B shows lowering of the platform once the object has been generated.
  • the platform moves down (in direction of arrow A) and the ejector rods 106 support the separator platform 104 and object 101.
  • the ejector rods hold the separator platform, such that the separator platform is no longer supported by the build platform.
  • the build platform may be shaken (e.g. in direction of B) or oscillated to enhance the sieving action of the powder through the separator platform to separate the object and aid its recovery from the bulk powder.
  • the separator platform is separated from the surface of the build platform.
  • the space between the separator platform and build platform is then to be filled by the powder as it is sieved through the separator platform.
  • the object remains atop the separator platform.
  • the separator platform is maintained in position by the ejector rods until the separator platform and object are above a level of the powder. Since the powder is selectively solidified to render the object the remaining powder is not solidified and remains largely in powder form. As such the remaining powder can flow or pass through the separator platform.
  • the powder goes down the separator platform with the aid of gravity and the alternating movement of the build platform. The oscillating motion helps the powder move more freely since it breaks up any agglomeration or voids within the powder.
  • control unit is configured to move the build platform in cycles of alternating movement up and down.
  • control unit may be configured to make the platform oscillate in small steps of around 0.5 mm, where the separator platform is separated the same amount from the build platform because of this movement.
  • the build platform may be moved in discrete steps using a continuous fixed nut and rotatable screw that are discretely controlled. As the build platform is lowered, excess powder surrounding the object falls through the separator platform to separate the object from the powder.
  • Figure 1 C shows the object 101 separated from the powder 102.
  • the object can then be easily removed.
  • the build platform can remain lowered when the object is removed.
  • the separated object may be removed from the separator platform before raising the build platform for powder recovery.
  • the drive unit may raise the platform in an oscillatory fashion (there may also be shaking of the platform as it rises) to sieve the separator platform above the powder and cause it to rise atop the powder (as the powder is raised on the platform).
  • the separator platform may then be removed and the powder can be recycled.
  • Figure 1 D shows that once the object is removed, the separator platform can be separated from the powder to allow recycling of the powder for subsequent rendering operations.
  • the drive unit and resilient elements can raise the build platform in an oscillatory fashion to sieve the separator platform above the powder. This causes the separator platform to rise atop the powder as the powder is raised on the platform so as to separate the separator platform from the powder.
  • the build platform and the separator platform can be raised together after removing the object.
  • the result of raising and/or lowering the build platform is that the separator platform sits atop the powder. Once the bulk powder is on the platform and under the separator platform, the separator platform may be removed. For example, the separator platform is removable for improved suction of powder from corners of the apparatus. Since the ejector rods are hidden below the build platform, a clear surface is provided on the build platform such that the powder can be removed with no obstacles, for example by suction or any other mechanical method. [0023]According to an example, the build platform may be lowered for a further raising and/or lowering operation to be performed. The build platform may then be raised in the oscillatory manner to sieve out the separator platform onto the powder.
  • Figure 2 shows a method for separating a three-dimensional rendered object from bulk powder.
  • a separator platform is arranged upon a build platform.
  • an object is rendered upon the separator platform.
  • the separator platform is supported independently of the build platform.
  • Ejector rods are provided which extend from the separator platform to a support layer onto which the ejector rods are mounted.
  • the build platform may be supported.
  • resilient elements may be attached to the ejector rods and which extend between the build platform and the support layer.
  • the build platform is raised and/or lowered relative to the separator platform using a drive unit that may be positioned below the build platform.
  • the object is separated from the bulk powder.
  • the tuning of the oscillation frequencies improves the powder removal. Tuning the vibration of the build platform stage according to powder type and/or humidity improves powder removal since cavities formed within the powder layer are collapsed. This then allows for the powder to fall through the separator platform more efficiently.
  • the oscillation frequency of the build platform and/or separator platform via the ejector rods can be tailored to powder properties. The provision of a build platform which is vibrated as it is raised or lowered whilst the separator platform is supported by the ejector rods allows a wider range of oscillation frequencies to be achieved.
  • the vibration frequency can be tuned using the drive unit and can be modified or tuned according to specific properties of the powder at the time of producing the object.
  • the apparatus and method described herein provides object separation from a powder matrix in which it is rendered more efficient. This is especially due to the wide range of oscillation frequencies which is achievable using the apparatus described.

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  • Engineering & Computer Science (AREA)
  • Chemical & Material Sciences (AREA)
  • Materials Engineering (AREA)
  • Manufacturing & Machinery (AREA)
  • Mechanical Engineering (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Robotics (AREA)

Abstract

Cette invention concerne un appareil et un procédé de séparation d'un objet construit tridimensionnel à partir d'une poudre en vrac. Une plateforme de séparation est disposée sur une plate-forme de construction sur laquelle un objet est construit. Des tiges d'éjection supportent la plate-forme de séparation indépendamment de la plate-forme de construction. Une unité d'entraînement est configurée pour séparer la plate-forme de construction de la plate-forme de séparation, de sorte à séparer l'objet sur la plate-forme de séparation de la poudre en vrac.
PCT/US2018/049040 2018-08-31 2018-08-31 Séparation d'objets imprimés Ceased WO2020046361A1 (fr)

Priority Applications (1)

Application Number Priority Date Filing Date Title
PCT/US2018/049040 WO2020046361A1 (fr) 2018-08-31 2018-08-31 Séparation d'objets imprimés

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
PCT/US2018/049040 WO2020046361A1 (fr) 2018-08-31 2018-08-31 Séparation d'objets imprimés

Publications (1)

Publication Number Publication Date
WO2020046361A1 true WO2020046361A1 (fr) 2020-03-05

Family

ID=69644582

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/US2018/049040 Ceased WO2020046361A1 (fr) 2018-08-31 2018-08-31 Séparation d'objets imprimés

Country Status (1)

Country Link
WO (1) WO2020046361A1 (fr)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3967429A1 (fr) * 2020-09-11 2022-03-16 Siemens Aktiengesellschaft Dispositif de séparation, machine de fabrication additive pourvue de dispositif de séparation, procédé de séparation et procédé de fabrication additive avec le procédé de séparation
FR3118430A1 (fr) * 2020-12-28 2022-07-01 Centre Technique des Industries Mécaniques Méthode et installation de fabrication additive

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010045678A1 (en) * 2000-05-25 2001-11-29 Minolta Co., Ltd. Three-dimensional modeling apparatus
EP1926585A1 (fr) * 2005-09-20 2008-06-04 PTS Software BV Appareil destiné à la fabrication d un article tridimensionnel et procédé de fabrication de cet article
US20170036399A1 (en) * 2015-08-06 2017-02-09 Well Smart Electronics Limited 3D printer

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20010045678A1 (en) * 2000-05-25 2001-11-29 Minolta Co., Ltd. Three-dimensional modeling apparatus
EP1926585A1 (fr) * 2005-09-20 2008-06-04 PTS Software BV Appareil destiné à la fabrication d un article tridimensionnel et procédé de fabrication de cet article
US20170036399A1 (en) * 2015-08-06 2017-02-09 Well Smart Electronics Limited 3D printer

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP3967429A1 (fr) * 2020-09-11 2022-03-16 Siemens Aktiengesellschaft Dispositif de séparation, machine de fabrication additive pourvue de dispositif de séparation, procédé de séparation et procédé de fabrication additive avec le procédé de séparation
WO2022053311A1 (fr) * 2020-09-11 2022-03-17 Siemens Aktiengesellschaft Dispositif de détachement, machine d'impression 3d pourvue du dispositif de détachement, procédé de détachement et procédé d'impression 3d accompagné du procédé de détachement
FR3118430A1 (fr) * 2020-12-28 2022-07-01 Centre Technique des Industries Mécaniques Méthode et installation de fabrication additive

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