WO2022081134A1

WO2022081134A1 - Build cake transporter

Info

Publication number: WO2022081134A1
Application number: PCT/US2020/055314
Authority: WO
Inventors: Jorge DIOSDADO BORREGO; David CHANCLON FERNANDEZ; Pablo Antonio MURCIEGO RODRIGUEZ
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2020-10-13
Filing date: 2020-10-13
Publication date: 2022-04-21

Abstract

A method of transporting a build cake created in an additive manufacturing system. The method comprises arranging a shuttle a build cake. The build cake is supported on a build support tray carried by a build platform. The build platform is raised to raise the build cake into an opening through the shuttle and the build support tray is secured to the shuttle. The build platform is lowered to allow non-solidified build material of the build cake to pass through openings in the build support tray and to fall onto the build platform.

Description

BUILD CAKE TRANSPORTER

[0001] Additive manufacturing systems can be used to manufacture three- dimensional (3D) objects. This can be achieved, for example, by forming successive layers of a build material on a build platform and selectively solidifying portions of those layers to build up a 3D object within a build cake. Objects such as product components can be built up in layers within the build cake in an additive manufacturing system in accordance with object descriptions as part of a build instruction that are interpreted and applied by a print controller.

[0002] Examples of the present disclosure will now be described with reference to the accompanying Figures, in which:

[0003] Figure 1 shows an example of apparatus that may be used in a method of transporting a build cake;

[0004] Figure 2 shows an different example of apparatus that may be used in a method of transporting a build cake;

[0005] Figure 3 shows an example method of transporting a build cake;

[0006] Figure 4 shows another example of a method of transporting a build cake;

[0007] Figures 5a to 5i show different example stages during the transport of a build cake; [0008] Figures 6a and 6b show close up views of portions of an example of a latch in operation;

[0009] Figure 7 shows a further example of apparatus that may be used in a method of transporting a build cake;

[0010] Figure 8 shows the details of an example arrangement of components of an apparatus that may be used in a method of transporting a build cake; and

[0011] Figure 9 shows a schematic diagram of controller.

[0012] Figure 1 shows an example of apparatus that may be used in a method of transporting a build cake. The build cake is created in an additive manufacturing process. In some examples, the additive manufacturing process used to create the build cake uses build material which is spread over a build platform to form a build layer in a build chamber. Selected portions of the build layer may be solidified, for example by fusing, sintering, melting, binding or otherwise joining the build material using, for example, heat energy applied from an energy source and a fusing agent. The build platform is then lowered by a predetermined amount and a new build layer formed on the previously formed layer and the process repeated. In this way the built object is created within a build cake which is made up of the built object and non-solidified build material.

[0013]The build material may comprise any suitable form of build material, for example fibres, granules or powders. The build material can include, for example, thermoplastic materials, ceramic material and metallic materials. A store of build material may be provided in a supply vessel and build material may be distributed from the supply vessel to form an intermediate volume of build material from which build material may be spread over a build platform, either directly such as using a roller to spread the intermediate volume, or indirectly by moving some or all of the intermediate volume to another location prior to spreading.

[0014] In some additive manufacturing processes, for example in some processes using metallic build materials, the built object within the build cake may be referred to as a green object as it may not be structurally robust until a further processing operation has been carried out, for example a sintering process.

[0015] As mentioned above, the apparatus of Figure 1 is an example of apparatus that can be used in a method of transporting a build cake, or built object. After a build cake is created in an additive manufacturing process a built object within the build cake may be transported to a post processing locations, or a plurality of post processing stations where post-processing operations can be performed. Automating such transport processed may reduce manual intervention which may increase the economic viability of large scale additive manufacturing in industry.

[0016] Figure 1 shows an example of apparatus 16 that may be used in a method of transporting a build cake 18 and / or a built object 20. Figure 3 shows a build cake 18 comprising built objects 20 and non-solidified build material 22. The build cake 18 of this example is a cuboid shape. The build cake 18 is arranged on a build support tray 24. The build support tray 24 comprises a support surface 26 which is secured on a frame 28. The frame 28 of the build support tray 24 is supported on a build platform 30 within a build chamber 32. The build platform 30 can be raised and lowered within the build chamber 32 to raise and lower the build support tray 24 and build cake 18 thereon.

[0017]The build platform 30 of this example is substantially rectangular and the support surface 26 of the build support tray 24 may be substantially the same size and shape as the build platform 30. This allows the build support tray 24 to support a build cake 18 across substantially all the area of the build platform 30.

[0018] Above the build chamber 32 there is positioned a laterally movable shuttle 34 which, in this example, is mounted to, and movable along, a rail 36 by a chassis 38. The shuttle 34 comprises an inner wall 40 which extends around a periphery of an opening 42 through the shuttle 34. The opening 42 through the shuttle is sized and shaped so that the build cake 18 can be raised through a bottom 46 of the opening 42 into the shuttle 34. The inner wall 40 of the shuttle 34 may be arranged such that the cross section of the opening 42 is substantially constant. The opening 42 may be substantially the same size and shape as the build platform 30 so that the inner wall 40 can support sides of the build cake 18 as it rises into the shuttle 34 through the bottom 46 of the opening 42.

[0019]The inner wall 40 may be taller than the build cake 18 so that the build cake 18 does not protrude from a top 48 of the opening 42 when the build platform 30 is raised to a level matching that of the bottom 46 of the opening 42. In other examples the build cake 18 may be taller than the inner wall 40 so that an upper portion of the build cake protrudes from a top 48 of the opening 42 when the build platform 30 is raised to level substantially matching that of the bottom 46 of the opening 42.

[0020]The shuttle comprises a latch 44 which can engage with the build support tray 24, in this example with the frame 28 of the build support tray 22, to secure the build support tray 26 to the shuttle 34. The latch 44 may be any suitable latching mechanism that engages, clamps or otherwise secures the build support tray 24 to the shuttle 34. There may be a plurality of latches 44 and they may be arranged in any suitable way to secure the build support tray to the shuttle. By secures the build support tray 24 to the shuttle 34 it is meant that the build support tray 24 does not fall away from the shuttle 34 when the build platform 30 is lowered

[0021] In this example the shuttle comprises a latch 44 on a side of the inner wall 40 and the latch is arranged adjacent a bottom 46 of the opening 42. The latch 40 of this example is an automatic latch controlled by a controller which controls the operation of the build cake transporter and may also control, or receive information from, a controller which controls, the additive manufacturing process which creates the build cake 18. [0022] Figure 2 shows another example of apparatus 116 that may be used in a method of transporting a build cake 18. The 116 is similar to the apparatus 16 shown in Figure 3 and like parts are labelled with the same reference numerals.

[0023] In this example the build platform 30 is located lower within the build chamber 32 so that there is a space between a top of the build cake 18 and a bottom 46 of the opining 42 through the shuttle 134.

[0024]The apparatus 116 includes a container 50. A base 52 of the container 52 is secured to an upper surface 54 of the shuttle 134. In this example the base 52 of the container 52 is secured to an upper surface 54 of the shuttle 134, but in other examples a base of the container 50 may be secured to other parts of the shuttle 134.

[0025]The container 50 extends above the shuttle 134 and over the opening 42 through the shuttle 134. In this way the container 50 and shuttle together form a housing with the bottom 46 of the opening 42 through the shuttle 134 providing access into an interior 76 of the housing. The container 50 of this example is closed at a top so that the housing is substantially closed with the exception of the opening 42 through the shuttle 134. As set out above, this arrangement may reduce the risk of non-solidified build material 22 escaping, for example being ejected or blown, from the build cake 18.

[0026] As shown, the internal wall 40 of the shuttle 134 is coupled to the chassis 138 of the shuttle 134 by resiliently deformable elements 56, in this example springs, so that the inner wall 40 can move relative to the chassis 138. It should be understood that, in other examples, the chassis may be connected to the inner wall by other mechanisms, or the chassis and wall may be integrally formed.

[0027]The shuttle 134 also includes a vibrator 58 coupled to an outside of the inner wall 40 of the shuttle 134 that is able to create vibrations in the wall 40. As the wall 40 is coupled to the chassis 138 by resiliently deformable elements 56 vibrations in the wall 40 are not readily passed to the chassis 138 or rail 36. It should be understood that in other examples where the inner wall 40 and chassis 138 are substantially rigidly connected, or are integrally formed, a vibrator 58 can be mounted to the inner wall 40 or chassis 138. Creating vibrations in the inner wall 40 will create vibrations in a build support tray 24 secured thereto.

[0028]The shuttle 134 of this example includes a plurality of latches 144 arranged on opposing sides of the opening 42. As above, the latches are arranged adjacent a bottom 46 of the opening 42. Four latches are provided, two on one side of the opening 42 and two on an opposing side of the opening 42. The latches 44 are arranged adjacent a bottom 46 of the opening 42.

[0029] Figure 3 shows an example method of transporting a build cake 18. The method 1 comprises arranging 2 a shuttle 34,134 above a build chamber 32 within which a build cake 1 Sis supported on a build support tray 24 that is itself by a build platform 30. Arranging the shuttle 34.134 above a build chamber 32 can facilitate the loading of a build cake 18 into the shuttle 34,134.

[0030]The build platform 30 is raised 4 to raise the build cake 18 into an opening 42 through the shuttle 34,134. The build support tray 30 is then secured 6 to the shuttle 34,134 and the build platform 30 is lowered 8 to leave the build support tray 24 supported by the shuttle 34,134. As the build platform 30 is lowered away from the build support tray 24 non-solidified build material 22 is allowed 10 to pass through openings in the build support tray 34,134. The non-solidified build material 22 that passes through openings in the build support tray 24 falls onto the build platform 30.

[0031]This method results in a build cake 18 being conveniently moved into a shuttle 34,134 and secured therein by securing the build support tray 24 to the shuttle 34,134. Lowering the build platform 30 and allowing non-solidified build material 22 to pass through openings in the build support tray 24 and fall to the build platform 30 removes at least a portion of the non-solidified build material 22 from the build cake thereby reducing the amount of non-solidified build material 22 that could leak during movement of the shuttle 34,134 and build support tray 24. It should be understood that the build cake is used herein to refer to a complete build cake 18 made during an additive manufacturing process and to a partial build cake comprising built objects 20 and unsolidified build material 22 carried on the build support tray 24 after at least some of the non-solidified build material 22 has passed through openings in the build support tray 24 and fall to the build platform 30.

[0032] With the build cake 18 secured to the shuttle 34,134 movement of the shuttle34,134 moves the build support tray 24 away from the build platform 30, for example to a further processing location.

[0033] As set out above, the build cake 18 may comprise a built object 20 and non-solidified build material 22 and further processing operations may include decaking operations, for example a coarse decaking operation in which nonsolidified build material is moved away from the built object, for example under gravity, and a fine decaking operation in which non-solidified build material remaining after a coarse decaking operation is removed from the built object, for example using air jets, for example high velocity air jets. Further processing operations may also include operations such a quality assessment of the built object, for example by carrying out measurements of the built object. Further processing operations may also include storage, cleaning, polishing, sintering or the like.

[0034] Figure 4 shows another example of a method 101 of transporting a build cake 18. As with method 1 , the method 101 comprises arranging 102 a shuttle 34,134 above a build cake 18 which is supported on a build support tray 24 carried by a build platform 30.

[0035]The build platform is raised 104 to raise the build cake 18 into an opening 42 through the shuttle 34,134. The build support tray 24 is then secured 106 to the shuttle 34,134.

[0036] With the build support tray 24 secured to the shuttle 34,134, the build platform 30 is lowered 108. This leaves the build cake 18 supported on the build support tray 24 above the build platform 30. [0037] N on-solidified build material 22 is then allowed 110 to pass through openings in the build support tray 24. The non-solidified build material 22 may be allowed to pass through the openings in the build support tray 24 under gravity alone, or energy may be applied to the build cake 18 to encourage the non-solidified build material to pass through the openings. The energy may be applied to the build cake 18 by vibrating the shuttle and I or build support tray.

[0038]At least some of the non-solidified build material 22 falls onto the lowered build platform thus removing it from the build cake. As noted above, this may reduce the risk of non-solidified build material leaking or falling from the container during subsequent movement of the container. Such leaking or falling of non-solidified build material could create a contamination risk, or hinder recycling or reuse of non-solidified powder.

[0039]With at least some of the non-solidified powder 22 removed from the build cake by passing through the openings in the build support tray 34 the shuttle is moved 14 away from the build platform 30 and therefore moves build support tray 24 secured thereto away from the build platform 30 to a further location.

[0040]A difference between the method 1 and this method 101 is that the method 101 includes securing 12 a base 52 of a container 50 to the shuttle 134. The base 52 of the container 50 is open and the container 50 extends above the shuttle 134 and over the opening 42 through the shuttle 134. The container 50 and shuttle 134 together may create an enclosed housing with the opening 42 through the shuttle 134 providing an opening into an interior 76 of the housing. The container 50 may be closed at a top so that the housing is substantially closed with the exception of the opening 42 through the shuttle 134. This arrangement may reduce the risk of non-solidified build material 22 escaping from a top surface of the shuttle 134, for example being ejected or blown from the build cake.

[0041 ]The container 50 may be secured to the shuttle 134 at any suitable stage during the process. The container 50 may be removed at any suitable stage during the process. In some examples the container 50 is secured to the shuttle 134 before the shuttle 134 is arranged above the build chamber 32 containing a build cake 18, while the shuttle 134 is arranged above the build cake 18, or after the build support tray 24 has been secured to the shuttle 134. The process of securing the build support tray 24 to the shuttle 134 could be an automated process, or, in some examples, the process may be manual. In some examples the container 50 is removed from the shuttle 134 after the build platform 30 has been lowered and non-solidified build material 22 has been allowed to flow through openings in the build support tray 24 onto the build platform 30, or after the shuttle 134 has moved to a further processing location.

[0042]The method may comprise placing a further build support tray on the build platform 30. After the build cake 18 has been removed from the build platform 30 and the build support tray 24 secured to the shuttle 134, the shuttle 134 can move away from the build platform 30, exposing the build platform 30 for further use. In this method, the build cake 18 is supported by a build support tray 24 which is located on the build platform 30. This may be achieved by creating the build cake 18 on the build support tray 24 using an additive manufacturing process.

[0043]The method may comprise removing non-solidified build material from the build platform 30. This may be an automated process, for example using vacuum tubes, scrapers, blowers and I or brushes, or may be a manual process. All of the non-solidified build material that is allowed to fall on to the build platform may be removed from the build platform, or some may be left on the build platform in preparation for future use.

[0044] Figures 5a to 5i show examples of apparatus at different example stages during the transport of a build cake 18.

[0045]These examples use the apparatus 116 of Figure 4. As set out above, above the build chamber 32 there is a shuttle 134 which is mounted to, and movable 60 along, the rail 36. As shown in Figure 5a the bottom 46 of the opening 42 through the shuttle 134 is offset from the build chamber 32 as the shuttle 134 moves towards a collection position.

[0046] Figure 5b shows the container shuttle 134 arranged above the build cake 18 so that the bottom 46 of the opening through the shuttle 134 is aligned with the build chamber 32 in a collection position.

[0047] Figure 5c shows the arrangement after the build platform 30 has raised the build cake 18 through the bottom 46 of the opening 42 and into the shuttle 134. The build platform 30 has been raised to a top of the build chamber 32 so that the build platform is substantially level with bottom 46 of opening 42 and the build support tray 24 is located within the opening 42. The latches 144 have been activated so that the build support tray 24 is secured to the shuttle 134. The latches 144 of this example are automatic latches controlled by a controller 74 which controls the operation of the build cake transporter and also controls the additive manufacturing process which creates the build cake 18. In other examples the controller 74 may not directly control the additive manufacturing process, but may receive information from, and provide instructions to a controller which controls the additive manufacturing process which creates the build cake 18. An example of a latch 144 will be described in more detail with reference to Figures 6a and 6b.

[0048]As the build cake 18 is shorter than the inner wall 40 the build cake does not protrude through the top 44 of the opening through the shuttle 134.

[0049] In Figure 5d the build platform 30 has been lowered to a position within the build chamber 32 leaving the build support tray 24 held above the build platform 30.

[0050]ln Figure 5e non-solidified build material 62 has passed through openings in the support surface 26 of build support tray 24 and has fallen onto the build platform 30 within the build chamber 32. The loss of non-solidified build material 62 from the build cake 18 causes the built objects 20 to drop to, and rest upon, the support surface 26 of the build support tray 24. [0051 ]The non-solidified build material 62 pass through the openings in the build support tray 24 and fall onto the build platform 30 under the action of gravity alone after the build platform 30 is lowered away from the build support tray 24.

[0052] In some examples the movement of the non-solidified build material 62 through the openings in the build support tray 24 is initiated, sped up or otherwise encouraged by vibrating a part of the shuttle 134. Vibrating a part of the shuttle 134 could include vibrating a part of the inner wall 40 using the vibrator 58 attached thereto, or could include moving the shuttle 134 rapidly back and forth to produce a vibration.

[0053] With non-solidified build material 62 removed from the shuttle 134 the shuttle 134 moves away from the build chamber 32 as shown in Figure 5f.

[0054] In Figure 5g the shuttle 134 has moved to a second location 64 which is separated from build chamber 32. This allows the build chamber 32 to be emptied of some, or all, of the non-solidified build material 62 allowing the build chamber 32 to be reused for the creation of a further build cake.

[0055] Figures 5h and 5i show different options for what can happen at the further location 64. In Figure 5h the latches 144 have been released and the build support tray 24 has been lowered from the shuttle 134 to allow access to the build objects 18. The shuttle 134 can then be moved to a different location.

[0056] Figure 5i shows a further option which can occur in addition to, or instead of, the removal of the build support tray 24 from the shuttle 134. The container 60 has been released and removed from the shuttle 134. In this example the build support tray 24 is still secured to the shuttle134 by the latches 144. This allows access to the top 44 of the opening 42 through the shuttle 134 so that access to the built objects is provided from above. This may facilitate the measurements of the built objects being taken, or quality control operations being carried out. [0057]Separating the build support tray 22 from the container 36, as in Figure 5h, or the container 36 from the shuttle 32 allows the build support tray 22 or container 36 and associated build support tray 22 to be moved elsewhere, or a processing operation to be carried out. The shuttle 32 could return to the further location 44 to collect the build support tray 22, or container 36 and associated build support tray 22.

[0058] With the shuttle 134 and build support tray 24 located away from the build chamber a second build support tray 24 can been placed on the build support platform 30 so that a further build operation can be carried out in the build chamber 32.

[0059] Figure 6a and 6b show close up views of portions of an example of a latch 144 in operation. The latch 144 includes a bolt 66 which, as shown in Figure 6a, is stored in a retracted position within the latch 144 when not actuated. When actuated the bolt 66 extends from the latch 144 and passes through the inner wall 40 of the shuttle 134 into a frame 28 of the build support tray 24 and thereby secures the build support tray 24 to the shuttle 134 as shown in Figure 6b. The bolt 66 of this example has a substantially cylindrical body extending along a bolt axis to tapered lead end. In this example, as the bolt 66 extends from the latch 144 it rotates about the bolt axis. Rotation of the bolt 66 as it extends from the latch 144 may facilitate passage of the bolt through non-solidified build material of the build cake. In other examples the bolt does not rotate as it extends from the latch. The bolt 66 may include grooves, ridges or other features which may assist in penetration of the bolt 66 through non-solidified build material of the build cake.

[0060]The bolt 66 of the latch 144 is moved into the retracted position as shown in Figure 6a when the latch is not activated and this releases the build support tray 24 from the shuttle 134. The latch 144 may include electromechanical, pneumatic, hydraulic or any other suitable mechanism which can cause actuation of the latch 144. [0061] Figure 7 shows another example of the build cake transporter. In Figure 7 a lid 68 closes a top of the container 150. The lid 68 can be opened to provide access to the top 48 of the opening 42 through the shuttle 134 and so to a build cake 18, or built objects 20 on a build support tray 24 secured to the shuttle 134. In this example the lid 68 is hinged at one side so that the lid 68 can be easily opened and closed. In other examples the lid 68 may be removable from the container 150.

[0062] Figure 8 shows the details of an example arrangement of components of a build cake transporter. These components have been introduced and, where possible will be given the same reference numerals as those used in reference to Figure 4. The main components comprise a shuttle 134, a build support tray 24, a container 250 and rails 36.

[0063]The shuttle 134 comprises an inner wall 40 defining an opening 42 through the shuttle 134. The inner wall 40 is coupled to a chassis 138 by resiliently deformable elements 56. The deformable elements 56 of this example comprise springs and allow the inner wall 40 to move relative to the chassis 138.

[0064]The inner wall 40 carries four latches 144 and a vibrator 58. There are two latches on one side of the inner wall 40 and two opposing latches 144 not visible, but arranged on an opposing side of the inner wall 40. The vibrator 58 can be activated to cause the inner wall 40 to vibrate and the resiliently deformable elements 56 hinder transmission of the vibrations from the inner wall 40 to the chassis 138. The chassis 138 is movably coupled to the rails 36 to allow the shuttle 134 to move along the rails 36.

[0065]The build support tray 24 comprises a support surface 26 and a frame 28. The support surface 26 includes openings 70 through which non-solidified build material can pass. The frame 28 includes openings 72 into which a bolt of the latches 144 can extend to secure the build support tray 24 to the shuttle 134. [0066] In one example the container 250 may be formed of a substantially transparent plastics material. The container 250 is releasably secured to the shuttle 134. In this case the container is secured to a top portion of the inner wall 40 adjacent the top 46 of the opening 42. In other examples the container 250 can be releasably secured to the chassis 138.

[0067] Figure 9 shows a schematic diagram of an apparatus 82 comprising a controller 84. The controller 84 may be suitable for use in the controller 74 in an additive manufacturing system. In this example the controller 82 comprises instructions to control an additive manufacturing apparatus to perform a method. The instructions 8comprising:

[0068] Instructions 86 to arrange a shuttle above a build cake, the build cake supported on a build support tray carried by a build platform.

[0069] Instructions 88 to raise the build platform so that the build cake enters an opening through the shuttle.

[0070] Instructions 90 secure the build support tray to the shuttle.

[0071] Instructions 92 to lower the build platform.

[0072] Instructions 94 to cause non-solidified build material of the build cake to pass through openings in the build support tray to fall onto the build platform.

Claims

1. A method of transporting a build cake created in an additive manufacturing system, the method comprising: arranging a shuttle above a build chamber housing a build cake, the build cake supported on a build support tray carried by a build platform; raising the build platform to raise the build cake into an opening through the shuttle; securing the build support tray to the shuttle; and lowering the build platform to allow non-solidified build material of the build cake to pass through openings in the build support tray and to fall onto the build platform.

2. A method as claimed in claim 1 , in which the method includes moving the build support tray away from build platform by moving the shuttle

3. A method as claimed in claim 2, in which the method comprises placing a further build support tray on the build platform.

4. A method as claimed in claim 1 , in which the method comprises removing non-solidified build material from the build platform.

5. A method as claimed in claim 1 , in which the method includes securing a base of a container to the shuttle, the container extending above the shuttle over the opening through the shuttle.

6. A build cake transporter comprising a shuttle and a container having an open base, a base of the container being releasably secured to a the shuttle, the shuttle being movable between a first location and a further location, the shuttle having an opening therethrough to receive a build cake from a build platform in the build location, the base of the shuttle being releasably securable to a build support tray so that movement of the shuttle causes movement of the build support tray, the container extending above the shuttle over the opening through the shuttle.

7. A build cake transporter as claimed in claim 6, in which the shuttle includes a vibrator to create vibrations in the shuttle or in a build support tray secured to the container.

8. A build cake transporter as claimed in claim 6, in which the shuttle comprises a latch for releasably securing a build support tray to the shuttle.

9. A build cake transporter as claimed in claim 8, in which the latch is an automatic latch which can be actuated by a controller.

10. A build cake transporter as claimed in claim 8, in which the latch includes a bolt extendable from the latch to releasably secure a build support tray to the shuttle, and the bolt of the latch rotates while extending.

11. An apparatus, the apparatus comprising a controller, the controller including instructions to control an additive manufacturing apparatus to perform a method, the method comprising: arranging a shuttle above a build cake, the build cake supported on a build support tray carried by a build platform; raising to build platform so that the build cake enters an opening through the shuttle; securing the build support tray to the shuttle; lowering the build platform; causing non-solidified build material of the build cake to pass through openings in the build support tray to fall onto the build platform.

12. Apparatus as claimed in claim 11 , in which the non-solidified build material is caused to pass through openings in the build support tray to fall onto the build platform by vibrating at least a part of the shuttle.

13. Apparatus as claimed in claim 12, in which the build cake contains a built object and non-solidified build material is allowed to pass through openings in the build support tray until the built object is resting on the build support tray.

14. Apparatus as claimed in claim 11 , in which the method includes using the transport shuttle to move the build support tray away from the build platform to a further processing station.

15. Apparatus as claimed in claim 11 , in which securing the build support tray to the shuttle comprises actuating a latch on the shuttle to engage the build support tray.

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