WO2022231601A1

WO2022231601A1 - 3d printing decaking stations

Info

Publication number: WO2022231601A1
Application number: PCT/US2021/029981
Authority: WO
Inventors: Jorge DIOSDADO BORREGO; Marc GARCIA GRAU
Original assignee: Hewlett-Packard Development Company, L.P.
Priority date: 2021-04-29
Filing date: 2021-04-29
Publication date: 2022-11-03

Abstract

A 3D printing decaking station is disclosed herein. The 3D printing decaking station comprises an interface to receive a build bed, the build bed comprising two vertically separated 3D objects and a build bed separator separating the build bed into two vertically independent sub-volumes in which a first 3D object is positioned in a first upper sub-volume and a second 3D object is positioned in a second lower sub-volume. The 3D printing decaking station further comprises a separator conveying mechanism to move the separator and the upper sub-volume to a cleaning module to enable a cleaning process to be performed thereon.

Description

3D PRINTING DECAKING STATIONS

BACKGROUND

[0001] Some additive manufacturing or three-dimensional printing systems generate 3D objects by selectively solidifying portions of successively formed layers of build material on a layer-by-layer basis. After object generation the build material which has not been solidified is separated from the 3D objects.

BRIEF DESCRIPTION OF THE DRAWINGS [0002] The present application may be more fully appreciated in connection with the following detailed description of non-limiting examples taken in conjunction with the accompanying drawings, in which like reference characters refer to like parts throughout and in which:

[0003] Figure 1A is a schematic front-view diagram showing an example of a 3D printing decaking station;

[0004] Figure 1 B is a schematic front-view diagram showing an example of another 3D printing decaking station;

[0005] Figure 2 is a block diagram showing a processor-based system example to control a 3D printing decaking station;

[0006] Figure 3 is a flowchart of an example method of controlling a 3D printing decaking station;

[0007] Figure 4 is a flowchart of another example method of controlling a 3D printing decaking station;

[0008] Figure 5 is a schematic front-view diagram showing an example of a 3D printing cleaning module; and

[0009] Figure 6 is a schematic front-view diagram showing another example of a 3D printing cleaning module.

DETAILED DESCRIPTION

[0010] The following description is directed to various examples of additive manufacturing, or three-dimensional printing, apparatus and processes involved in the generation of 3D objects. Throughout the present disclosure, the terms “a” and “an” are intended to denote at least one of a particular element. In addition, as used herein, the term “includes” means includes but not limited to, the term “including” means including but not limited to. The term “based on” means based at least in part on.

[0011] For simplicity, it is to be understood that in the present disclosure, elements with the same reference numerals in different figures may be structurally the same and may perform the same functionality.

[0012] 3D printers generate 3D objects based on data from a 3D object model of an object or objects to be generated, for example, using a CAD computer program product. 3D printers may generate 3D objects by selectively processing layers of build material. For example, a powder-based 3D printer may selectively treat portions of a layer of build material, e.g., a powder, corresponding to a layer of a 3D object to be generated, thereby leaving the portions of the layer un-treated in the areas where no 3D object is to be generated. The combination of the generated 3D objects and the un-treated build material may also be referred to as a build bed.

[0013] Suitable powder-based build materials for use in additive manufacturing include polymer powder, metal powder or ceramic powder. In some examples, non-powdered build materials may be used such as gels, pastes, and slurries. [0014] 3D printers may selectively treat portions of a layer of build material by, for example, ejecting a printing liquid or print agent in a pattern corresponding to cross-sectional slices of the 3D object. Examples of printing liquids may include fusing agents, detailing agents, binder agents or any printing liquid suitable for the generation of a 3D object. Additionally, the chemical composition of some printing liquids may include, for example, a liquid vehicle and/or solvent to be at least partially evaporated once the printing liquid have been applied to the build material layer. For simplicity, the liquid vehicle and/or solvents may be referred hereinafter as solvents. Other 3D printers however, may selectively treat portions of the layer of build material by controlling a focused energy source (e.g., a laser or an array of lasers) to emit energy to the areas of the build material layer which are intended to be solidified. Such printers may include selective laser sintering (SLS) printers.

[0015] Some three-dimensional printing systems use fusing agents to treat the portions of the layer of build material. The portions in which the fusing agent is applied are further heated so that the fusing agent absorbs such energy to heat up and melt, coalesce and solidify upon cooling the portions of build material on which the fusing agent was ejected thereto. The three-dimensional printing system may heat the build material by applying energy from an energy source to each layer of build material.

[0016] Some three-dimensional printing systems use a thermally curable binder agent which has to be heated to a predetermined temperature to cause components of the liquid binder agent to bind together particles of build material on which it is applied. Such a liquid binder agent may comprise latex particles and curing of the binder may occur, for example, at a temperature above 40 degrees Celsius, above 70 degrees Celsius, above 100 degrees Celsius, or above 120 degrees Celsius, or above 150 degrees Celsius.

[0017] Such binder agents may be applied to successive layers of powdered build material, such as powdered stainless steel (e.g., SS316L) build material, and the curing of the binder agent leads to the generation of so-called “green parts.” Green parts are generally relatively low-density objects formed by a matrix of cured binder and metal build material particles. Green parts are transformed into highly dense final objects by heating them in a sintering furnace to a temperature close to the melting point of the build material used.

[0018] After the completion of the green part generation process, the build volume comprises a set of generally relatively weakly bound green parts surrounded by generally unbound build material. Before green parts are transferred to the sintering oven, the unbound build material has to be separated from the green parts. In some examples, vibration and air-blowing techniques may be used to remove unbound build material. The application of vibration and air blowing techniques cause the green parts to move and/or collide with each other and thereby potentially cause some damage on them.

[0019] To increase efficiency of 3D printers, it is desirable to effectively use as much of the build chamber height as possible. As such, it may be beneficial to generate a plurality of 3D objects stacked vertically on top of each other within the build bed. However, when the 3D objects which are located in the higher layers of objects are separated from the non-treated build material during the decaking process, these 3D objects may collide with 3D objects formed lower in the build bed which may damage the objects. In the examples herein, a 3D object may be a fully fused 3D object or a green part.

[0020] The examples described herein provide a 3D printing decaking station to allow decaking of 3D objects which have been printed on top of each in a way that prevents or significantly avoids the objects being damaged through collision with other objects during a decaking process. Such a system thus helps increase the efficiency of 3D printer by allowing multiple objects to be vertically stacked within a build chamber.

[0021] Figure 1A is a schematic front-view diagram showing an example of a 3D printing decaking station 100A. A 3D printing decaking station is a post processing station within a 3D printing ecosystem in which a build bed is decaked. In the examples herein, decaking should be understood as the process of partially or totally removing the un-treated build material (e.g., build material that is non- coalesced, non-fused, unsolidified, and/or non-bound) from the generated 3D objects within the build bed. In some examples, the 3D printing decaking station 100A may be also referred to as 3D printing depowdering station or 3D printing cleaning station. In some examples, the 3D printing decaking station 100A may be a stand-alone machine. In other examples, the 3D printing decaking station 100A may be implemented in a 3D printer. In yet other examples, the 3D printing decaking station 100A may be implemented in a build material processing station. [0022] The 3D printing decaking station 100A comprises an interface 110, such as an enclosure, in which the 3D printing decaking station 100A is to receive a build bed 130. In some examples, the interface 110 may be a totally enclosed structure with a lid or door to receive the build bed 130. In other example, the interface 110 may be a partially enclosed structure. The build bed 130 may be received within the interface 110 by means of, for example, a portable build unit or a build bed transfer mechanism (not shown). As such, in some examples, the build bed 130 may not be present in the 3D printing decaking station 100A, for example during shipping or when not operating. In other examples, e.g., in use, the build bed 130 may be present in the 3D printing decaking station 100A. [0023] The build bed 130 comprises two vertically separated 3D objects: a first 3D object 145A and a second 3D object 145B. In the examples herein, the term vertically separated objects may be understood as meaning objects that do not coincide in any horizontal plane. The build bed 130 further comprises a substantially horizontal build bed separator 160 within the vertical separation, thereby separating the build bed 130 into two vertically independent sub-volumes, a first upper sub-volume 140A and a second lower sub-volume 140B. A separator 160 should be understood as an element comprising a substantially planar profile spanning substantially the same surface as the platform from the 3D printer that generated the build bed 130. Additionally, in some examples, the build bed 130 may further comprise a base separator (not shown) below the second lower sub volume 140B as the base of the build bed 130.

[0024] The build bed 130 includes the first 3D object 145A in the first upper sub volume 140A and the second 3D object 145B in the lower sub-volume 140B. The build bed 130 has been generated previously by any additive manufacturing means, for example fluid deposition techniques (including the ejection of fusing agent), SLS or the like.

[0025] In other examples, however, the build bed 130 may comprise additional 3D objects positioned within the first and second sub-volumes (145A, 145B). Additionally, or alternatively, the build bed 130 may comprise additional horizontal separators 160 thereby generating corresponding additional sub-volumes within which a plurality of 3D objects may have been generated.

[0026] The 3D printing decaking station 100A also comprises a separator conveying mechanism 120. The separator conveying mechanism 120 is a mechanism suitable for moving the separator 160 and the sub-volume 140A located directly thereon, to a cleaning module 170 to thereby enable a cleaning process to be performed thereon. The cleaning process involves the partial or complete separation of the un-treated build material from the generated 3D objects (e.g., first 3D object 145A). Some examples of cleaning modules 170 are disclosed herein with reference to Figures 5 and 6. The separator conveying mechanism 120 is further controllable to move any other separator or the base separator, if present, along with the respective sub-volume located thereon to the cleaning module 170. In some examples, the cleaning module 170 is part of the 3D printing decaking station 100A. However, in other examples, the cleaning module 170 is external but interacts with the 3D printing decaking station 100A. [0027] Figure 1 B is a schematic front-view diagram showing an example of another 3D printing decaking station 100B. The 3D printing decaking station 100B may be similar to the 3D printing decaking station 100A and thus may involve some of the same elements referred to with the same reference numerals. As such, the 3D printing decaking station 100B includes the interface 110 and the separator conveying mechanism 120. The 3D printing decaking station 100B interacts with the build bed 130 and the cleaning module 170.

[0028] The 3D printing decaking station 100B further comprises a build bed lifting mechanism 180 to vertically raise the build bed 130 once present in the interface 110. The build bed lifting mechanism may be implemented in a number of different ways, for example through a controllable pneumatic piston or any other suitable actuator. In some examples, the build bed lifting mechanism 180 may comprise a platform thereon (not shown) comprising a horizontal surface to hold the build bed 180. In other examples, such as in the examples in which the base separator is present in the build bed, the build bed lifting mechanism 180 may not comprise the platform thereon and the base separator (along with the build bed 130 thereon) may be placed directly on the build bed lifting mechanism 180.

[0029] The 3D printing decaking station 100B further comprises a controller 150. The controller comprises a processor 155 and a memory 157 with specific control instructions stored therein to be executed by the processor 155. The controller 150 is coupled to the separator conveying mechanism 120 and the build bed lifting mechanism 180. The controller 150 controls at least some of the operations of the elements that it is coupled to. The functionality of the controller 150 is described further below with reference to Figures 2, 3 and 4.

[0030] For simplicity, in the foregoing examples, reference to a 3D printing decaking station 100 is made including the 3D printing decaking station 100A and/or the 3D printing decaking station 100B. [0031] Figure 2 is a block diagram showing a processor-based system 200 example to control a 3D printing decaking station, for example the 3D printing decaking station 100 of Figure 1A-1 B. In some examples, the system 200 may be included in the controller 150 of Figure 1 B. In the examples herein, the instructions of system 200 may involve previously disclosed elements from Figures 1 A-1 B referred to with the same reference numerals. In some examples, the system 200 may be implemented in the 3D printing decaking station 100A of Figures 1A or the 3D printing decaking station 100B of Figures 1 B.

[0032] In some implementations, the system 200 is a processor-based system and includes a processor 210 coupled to a machine-readable medium 220. The machine-readable medium comprises instructions 221-225 that, when executed by the processor 210 causes the system 100A and/or 100B to operate in accordance with the methods outlined in the flow diagrams of Figures 3 and 4. [0033] Figure 3 is a flowchart of a method 300 of controlling the 3D printing decaking station 100. The method 300 may involve previously disclosed elements from Figures 1A and 1 B referred to with the same reference numerals. In some examples, parts of method 300 may be executed by a controller, such as controller 150 from Figure 1 B.

[0034] In some examples, the method 300 may start by receiving the build bed 130 as disclosed in the examples above in the interface 110 of the 3D printing decaking station 100. In other examples, the method 200 starts after the build bed 130 is received within the interface 110.

[0035] At block 320, the controller 150 determines the vertical position of the separator 160 within the build bed 160. In one example, the determination may be made based on data received by the controller 150 that indicates a vertical position at which the separator was placed by a 3D printer. In some examples, the build unit or the build bed transfer means may include a data repository (e.g., memory, RFID, bar code, QR code, etc.) in which the data has been previously encoded. A suitable device may then read the data and send it to the controller 150. In other examples, the controller 150 may access the data in a wireless manner (e.g., Cloud, Local Network). In another example, the determination may be made by a sensor, a vision system, or in any other suitable manner. [0036] At block 340, the controller 150 controls, based on the data, the build bed lifting mechanism 180 to raise the build bed 130 such that the separator 160 is in a position at which the separator conveying mechanism 120 can move it to the cleaning station 170.

[0037] At block 360, the controller 150 controls the separator conveying mechanism 120 to move the separator 160 and the upper sub-volume 140A including the first 3D object 145A to the cleaning module 170. In some examples, the controller 150 directly controls the separator conveying mechanism 120, for example the controller 150 controls a pneumatic piston to actuate the separator 160 and slide it horizontally to the cleaning module 170 with the aid of a set of rails or conveying rollers. In some examples, before the movement of the separator! 60, the controller 150 may further control a latching mechanism or a grabbing element to latch the separator 160 within the build unit 130 to the set of rails or conveying rollers. Additionally, in other examples, the controller 150 controls an intermediate element, such as an actuator, that in turn causes the separator conveying mechanism 120 to move the separator 160 and the upper sub-volume 140A to the cleaning module 170.

[0038] Figure 4 is a flowchart of an example method 400 of controlling the 3D printing decaking station 100 in which the interface 110 is to receive the build bed 130 with a plurality of build bed separators 160 separating the build bed 130 into a respective plurality of object-containing sub-volumes. In some examples, the build bed 130 comprises a further base separator positioned under the second lower sub-volume 140B. The method 400 may involve previously disclosed elements from Figures 1 A and 1 B referred to with the same reference numerals. In some examples, parts of method 400 may be executed by a controller, such as controller 150 from Figure 1 B.

[0039] At block 420, the controller 150 determines data corresponding to the vertical positions of each of the separators 160 within the build bed 130. In some examples, the build unit or the build bed transfer means may include a data repository (e.g., memory, RFID, bar code, QR code, etc.) in which the data has been previously encoded. A suitable sensor or device may then read the data and send it to the controller. In other examples, the controller 150 may access to the data through a look-up table or memory repository in a wireless manner (e.g., Cloud, Local Network).

[0040] At block 440, the controller 150 controls the build bed lifting mechanism 180 to successively position each separator 160 at a position at which the separator conveying mechanism 120 can move them, one after the other, to the cleaning module 170.

[0041] At block 460, the controller 150 controls the separator conveying mechanism 120 to successively move each separator and the corresponding sub volume located thereon to the cleaning module 170.

[0042] At decision block 480, the controller 150 determines whether an additional separator or the base separator is still present in the build unit. If so (i.e. , decision YES), the controller 150 executes block 440 again. In some example, the controller 150 may execute the subsequent block 440 after a predetermined time delay. The time delay may be based on a pre-configured time delay between the execution of block 460 and block 440 which, in some examples, has been encoded by a user. In other examples, the time delay may be based on a feedback signal indicative that the decaking operation of the sub volume corresponding to the previously moved separator to the cleaning module 170 has been completed. If, at decision block 480, the controller 150 determines that there are no additional separators or the base separator in the build unit (i.e., decision NO), the controller 150 determines that the decaking of the build bed 130 has been completed and a subsequent build bed to be decaked can be introduced to the interface 110.

[0043] Figure 5 is a schematic front-view diagram showing an example of a 3D printing decaking station 500 including a cleaning module 570. The cleaning module 570 is an implementation of the cleaning module 170 from Figures 1A and 1 B. The 3D printing decaking station 500 may involve previously disclosed elements from Figures 1 A and 1 B referred to with the same reference numerals. The 3D printing decaking station 500 includes the interface 110, the separator conveying mechanism 120 and the controller 150. The 3D printing decaking station 500 interacts with the build bed. [0044] The cleaning module 570 includes a hopper 580 to receive non-solidified build material from a build bed 130 sub-volume when positioned over the hopper 580. The hopper 580 may have any shape suitable for receiving the build material, for example, pyramidal, conical, cubical, spherical or the like. In an example, the hopper 580 has an internal volume corresponding to a sub-volume of the print bed 130, for example the larger of the first and/or second sub-volumes (140A, 140B). In another example, the hopper 580 has an internal volume corresponding to the volume of the entire build bed 130.

[0045] At block 360 from Figure 3, the controller 150 controls the separator conveying mechanism 120 is to move the separator 160 and the upper sub volume 140A including the first 3D object 145A over the hopper 580. In these examples, the separator 160 comprises apertures which are large enough such that the non-treated build material particles (e.g., particles of the first sub-volume 140A) may flow therethrough (see, e.g., arrow 585) towards the hopper 580 and small enough such that the 3D generated objects (e.g., first 3D object 145A) or small geometrical features from the 3D generated objects do not flow through or clog the apertures. In this manner, the non-treated build material particles are separated from the generated 3D objects.

[0046] Additionally, in some examples, the cleaning module 570 may further comprise a controllable vibrating mechanism 590 (e.g., vibration plate, eccentric motor) coupled to the controller 150 that causes the vibration mechanism to vibrate the separator 160 when located over the hopper 580. The vibration causes the at least a portion of the non-treated build material to flow through the apertures into the hopper 580. In some examples, the non-treated build material is may be reused in generating further 3D objects.

[0047] In some examples, a controller 150 may control the vibrating mechanism 590 to vibrate at very high frequencies (e.g., ultrasounds) for example at 20kHz, and at low amplitudes, for example of 20 microns. Vibrating at high frequencies and low amplitudes enables gentle removal of build material from 3D objects. However, the controller 150 may control the vibrating mechanism 590 to vibrate at lower frequencies, for example 35 Hz, and higher amplitudes, for example 1 mm. Additionally or alternatively, the controller 150 controls the vibrating mechanism 590 based on data corresponding to the sub-volume located over the hopper 580 and/or the geometry of the 3D objects within that sub-volume (e.g., first 3D object 145A within the first upper sub-volume 140A).

[0048] Figure 6 is a schematic front-view diagram showing an example of a 3D printing decaking station 600 including a cleaning module 670. The cleaning module 670 is an implementation of the cleaning module 170 from Figures 1A and 1 B. The 3D printing decaking station 600 may involve previously disclosed elements from Figures 1 A and 1 B referred to with the same reference numerals. The 3D printing decaking station 600 includes the interface 110, the separator conveying mechanism 120 and the controller 150. The 3D printing decaking station 600 interacts with the build bed 130.

[0049] At block 360 from Figure 3, the controller 150 controls the separator conveying mechanism 120 moves the separator 160 and the upper sub-volume 140A including the first 3D object 145A into the cleaning module 670. In some examples, the cleaning module when in use is a closed and air-tight volume. [0050] The cleaning module 670 comprises a blowing device 680 located at a position above the separator 160 once in the separator 160 is in cleaning module 670. The blowing device 680 is to blow a gas towards the sub-volume (e.g., upper sub-volume 140A). The blowing device 680 is connectable to a gas flow source (not shown). In some examples, the gas flow source may be part of the 3D printing decaking station 600. In other examples, however, the gas flow source may be external from the 3D printing decaking station 600 and connectable to blowing device 680.

[0051] The blowing device 680 is controlled by the controller 150 and comprises a channel which is to blow a gas flow to remove non-treated build material from the sub-volume. The removed build material is exhausted (e.g., arrow 685) through an exhaust port or vent (not shown). The exhaust port of vent may be subject to vacuum conditions to enhance the build material removal.

[0052] The blowing device comprises an output port (not shown). Some examples of the output port may include a static blowing nozzle, a directional blowing nozzle, an airknife or a combination thereof. In the present disclosure, an airknife may be implemented as a pressurized air plenum containing a series of holes (e.g., nozzles) or continuous slots through which pressurized air exits in a laminar flow. In some examples, the gas flow is an air flow. In other examples, the gas from the gas flow may be another gas, such as nitrogen.

[0053] The drawings in the examples of the present disclosure are some examples. It should be noted that some units and functions of the procedure may be combined into one unit or further divided into multiple sub-units. 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. Many variations are possible within the scope of the disclosure, which is intended to be defined by the following claims and their equivalents.

Claims

CLAIMS WHAT IT IS CLAIMED IS:

1. A 3D printing decaking station comprising: an interface to receive a build bed, the build bed comprising two vertically separated 3D objects and a build bed separator separating the build bed into two vertically independent sub-volumes in which a first 3D object is positioned in a first upper sub-volume and a second 3D object is positioned in a second lower sub-volume; a separator conveying mechanism to move the separator and the upper sub-volume to a cleaning module to enable a cleaning process to be performed thereon.

2. The 3D printing decaking station of claim 1 , comprising the build bed.

3. The 3D printing decaking station of claim 1 , further comprising the cleaning module.

4. The 3D printing decaking station of claim 3, wherein the cleaning module comprises a hopper; wherein the separator conveying mechanism is to move the separator and the upper sub-volume over the hopper; and wherein the separator comprises apertures in which non-treated build material of the first sub-volume may flow towards the hopper.

5. The 3D printing decaking station of claim 4, wherein the cleaning module comprises: a vibrating mechanism to vibrate the separator when located over the hopper; and the controller to control the vibrating mechanism to vibrate and cause non- treated build material to flow through the apertures to the hopper.

6. The 3D printing decaking station of claim 5, wherein the controller is to control the vibrating mechanism based on data corresponding to the sub-volume located over the hopper and/or the geometry of the 3D objects within the sub volume.

7. The 3D printing decaking station of claim 3, wherein the cleaning module comprises: a blowing device located at a position above the separator once in the cleaning module, to blow a gas towards the sub-volume; and the controller to control the blowing device to blow the gas to remove non- treated build material from the sub-volume.

8. The 3D printing decaking station of claim 7, wherein the blowing device comprises an output port in the form of a nozzle and/or an airknife.

9. The 3D printing decaking station of claim 1 , further comprising: a build bed lifting mechanism to vertically raise the build bed; a controller to: determine data corresponding to the vertical position of the separator within the build bed; control the build bed lifting mechanism to raise the build bed such that the separator is in a position at which the separator conveying mechanism can move it to the cleaning module; and control the separator conveying mechanism to move the separator and the upper sub-volume to the cleaning module.

10. The 3D printing decaking station of claim 9, wherein the build bed further comprises a base separator below the second lower sub-volume, the controller further to: control the build bed lifting mechanism to raise the build bed such that the base separator is in a position at which the separator conveying mechanism can move it to the cleaning module; and control the separator conveying mechanism to move the base separator and the second lower sub-volume to the cleaning module.

11. The 3D printing decaking station of claim 9, wherein the interface is to receive the build bed with a plurality of build bed separators separating the build bed into a respective plurality of object-containing sub-volumes; the controller further to: determine data corresponding to the vertical positions of each of the separators within the build bed; control the build bed lifting mechanism to successively position that each separator at a position at which the separator conveying mechanism can move them to the cleaning module; control the separator conveying mechanism to successively move each separator and the corresponding sub-volume located thereon to the cleaning module.

12. The 3D printing decaking station of claim 1 , implemented in a 3D printer or a build material processing station.

13. A method comprising: receiving a build bed in an interface of a 3D printing decaking station, the build bed comprising two vertically separated 3D objects and a build bed separator separating the build bed into two vertically independent sub-volumes in which a first 3D object is positioned in a first upper sub-volume and a second 3D object is positioned in a second lower sub-volume; raising the build bed such that a separator is in a position at which the separator conveying mechanism can move it to a cleaning module; and moving, through the separator conveying mechanism, the separator and the upper sub-volume to the cleaning module.

14. A non-transitory machine-readable medium storing instructions executable by a processor, the non-transitory machine-readable medium comprising: instructions to receive a build bed in an interface of a 3D printing decaking station, the build bed comprising two vertically separated 3D objects and a build bed separator separating the build bed into two vertically independent sub-volumes in which a first 3D object is positioned in a first upper sub-volume and a second 3D object is positioned in a second lower sub-volume, wherein the build bed further comprises base separator under the second lower sub-volume; instructions to raise the build bed such that a separator conveying mechanism is in a position at which the separator conveying mechanism can move the separator to the cleaning module; instructions to control the separator conveying mechanism to move the separator and the upper sub-volume to the cleaning module; instructions to raise the build bed for a distance such that the separator conveying mechanism is in a position at which the separator conveying mechanism can move the base separator to the cleaning module; and instructions to control the separator conveying mechanism to move the base separator and the second lower sub-volume to the cleaning module.

15. The non-transitory machine-readable medium of claim 14, implemented in the 3D printing decaking station of claim 1.