Hopper system

Abstract

A hopper system (1) for a binder jetting machine (2), comprising a support frame (3), fastenable to the machine (2); a plurality of hoppers (4), wherein each hopper (4) is adapted to contain binder jetting powders (5); a switching actuator (6), wherein the switching actuator (6) is configured to pick a hopper (4) of the plurality of hoppers (4) positioned in a resting position and transport the picked hopper (4) from the resting position to a dispensing position.

Description

“HOPPER SYSTEM”

[0001] Field of the invention

[0002] The present invention relates to a hopper system, in particular a hopper system installable in a binder jetting machine.

[0003] Background art

[0004] Binder jetting is an additive production technology that uses a bed of powders. It consists in depositing drops of liquid binder for selectively joining the powder particles to create shaped parts, which are then subjected to a sintering process. The process, repeated layer on layer, is used to create three-dimensional items.

[0005] Contrarily to many common additive production technologies using a heat source to melt together raw materials or light to selectively harden a liquid crosslinking, binder jetting glues the solid parts to form the geometry layer by layer so that heat is not required during the manufacturing. Moreover, the unbound powder temporarily supports disconnected portions of the component. This allows the formation of complex structures and internal volumes.

[0006] Moreover, binder jetting technology can be adapted to almost all powders, with high production rates and little raw material waste, which makes it particularly promising for the luxury field, for example, for making jewelry.

[0007] Binder jetting technology is performed by means of binder jetting machines which generally comprise a printing plane on which a powder bed is deposited and distributed by means of a hopper. Binder jetting machines further comprise a printing head for releasing minuscule drops of binder onto the powder bed and a system for moving the printing plane configured to cyclically lower the printing plane in order to repeat the process of depositing the powders and dispensing the liquid binder.

[0008] Although it is promising and advantageous, binder jetting technology still has various drawbacks.

[0009] One drawback of binder jetting technology is due to the complexity or impossibility of printing three-dimensional metal items made with different materials or colors, which are particularly required for making jewelry and various items of the luxury field.

[0010] Therefore, the need is felt to provide an improved binder jetting machine compared to the machines of the prior art.

[0011] Solution

[0012] It is the object of the present invention to provide a binder jetting machine which solves at least some of the drawbacks of the prior art.

[0013] It is a particular object of the present invention to provide a binder jetting machine which allows easily and quickly printing three-dimensional metal items made with different metals or colors.

[0014] This and other objects are achieved by a hopper system for a binder jetting machine, and by a binder jetting machine, according to the independent claims.

[0015] The dependent claims relate to preferred and advantageous embodiments of the present invention.

[0016] Figures

[0017] In order to better understand the invention and appreciate the advantages thereof, some non-limiting exemplary embodiments thereof will be described below with reference to the accompanying drawings, in which:

[0018] - Figure 1 is a diagrammatic perspective view of a hopper system according to an embodiment of the invention;

[0019] - Figure 2 is a diagrammatic perspective view of a binder jetting machine according to an embodiment of the invention.

[0020] Description of some preferred embodiments

[0021] With reference to the figures, a hopper system is generally indicated by reference numeral 1 .

[0022] The hopper system 1 is particularly adapted to be installed in a binder jetting machine 2, i.e., a machine or apparatus configured to perform 3D printing by means of binder jetting technology.

[0023] The hopper system 1 comprises a support frame 3. The support frame 3 is fastenable to machine 2, in particular in a stationary manner.

[0024] The hopper system 1 further comprises a plurality of hoppers 4.

[0025] Each hopper 4 is adapted to contain powders 5, in particular powders 5 adapted to perform binder jetting technology.

[0026] The hopper system 1 further comprises a switching actuator 6.

[0027] The switching actuator 6 is configured to pick a hopper 4 from the plurality of hoppers 4 positioned in a resting position, where hopper 4 is not usable by the hopper system 1 to dispense the powders 5, and transport the picked hopper 4 from the resting position to a dispensing position, where hopper 4 is usable by the hopper system 1 to dispense the powders 5.

[0028] Advantageously, a hopper system 1 thus configured allows easily and quickly printing three-dimensional items with different metal materials or colors.

[0029] In fact, the hopper system 1 thus configured allows storing different types of binder jetting powders 5 inside different hoppers 4. Therefore, the hopper system 1 thus configured allows arranging a plurality of hoppers 4 containing different powders 5 and selectively using the different hoppers 4, by picking a respective hopper 4 from the resting position and positioning it in the dispensing position, to dispense the respective powder 5 contained in the respective hopper 4. In order to print three-dimensional items with different metal materials or colors, hopper 4 previously positioned in the dispensing position can be repositioned in the resting position by means of the switching actuator 6, and a different hopper 4 containing a different powder 5 is then pickable from the resting position and positionable in the dispensing position by means of the switching actuator 6, to dispense the different powder 5.

[0030] According to an embodiment, the hopper system 1 comprises a carriage 7.

[0031] Carriage 7 is connected to the support frame 3 so as to be translatable with respect to the support frame 3 along a translation axis 8.

[0032] According to an embodiment, when positioned in the resting position, the hoppers 4 are adjacent to one another along a direction parallel to the translation axis 8.

[0033] According to an embodiment, the plurality of hoppers 4 is connected to carriage 7.

[0034] Advantageously, the hoppers 4 are thus translatable with respect to the support frame 3 along a translation axis 8.

[0035] According to an embodiment, the switching actuator 6 is connected to the support frame 3 so as to be translatable with respect to the support frame 3 along a coupling axis 15. The coupling axis 15 is transverse to the translation axis 8.

[0036] According to an embodiment, the hopper system 1 comprises removable coupling means 9.

[0037] The removable coupling means 9 are positioned on the plurality of hoppers 4 and on the switching actuator 6.

[0038] Moreover, the removable coupling means 9 are configured to allow a coupling or detachment, and vice versa, between the switching actuator 6 and a respective hopper 4 of the plurality of hoppers 4.

[0039] Advantageously, the switching actuator 6 is capable of picking a hopper 4 from the resting position, positioning it in the dispensing position, and then repositioning it and releasing it in the resting position, by means of the removable coupling means 9.

[0040] According to an embodiment, the hopper system 1 comprises an actuation system 10.

[0041] The actuation system 10 is configured to actuate a translation of the plurality of hoppers 4 with respect to the support frame 3.

[0042] Moreover, the actuation system 10 is configured to actuate a translation of the switching actuator 6 with respect to the support frame 3.

[0043] According to an embodiment, the hopper system 1 comprises an electronic processing unit 11 . The electronic processing unit 1 1 is configured to control the actuation system 10.

[0044] According to an embodiment, the actuation system 10 comprises an electric motor 12 and a transmission 13.

[0045] According to an embodiment, transmission 13 is connected to the electric motor 12 and the switching actuator 6. Specifically, transmission 13 is configured to transmit a movement originating from the electric motor 12 to the switching actuator 6. Thereby, a rotation of a drive shaft of the electric motor 12 corresponds to a translation of the switching actuator 6 with respect to the support frame 3.

[0046] According to an embodiment, transmission 13 is connected to the electric motor 12 and to the plurality of hoppers 4, preferably to carriage 7. Specifically, transmission 13 is configured to transmit a movement coming from the electric motor 12 to the plurality of hoppers 4, preferably to carriage 7. Thereby, a rotation of a drive shaft of the electric motor 12 corresponds to a translation of the plurality of hoppers 4, preferably of carriage 7, with respect to the support frame 3.

[0047] According to an embodiment, the support frame 3 comprises at least one threaded bar 14, preferably a plurality of threaded bars 14.

[0048] The threaded bar 14 extends in a direction parallel to the coupling axis 15.

[0049] According to an embodiment, the switching actuator 6 comprises at least one threaded nut wall 16.

[0050] The at least one threaded nut wall 16 of the switching actuator 6 extends in a direction parallel to the coupling axis 15.

[0051] According to an embodiment, the at least one threaded nut wall 16 of the switching actuator 6 is coupled to the at least one threaded bar 14 of the support frame 3 by means of a threaded connection.

[0052] According to an embodiment, the switching actuator 6 and the support frame 3 are connected so that a rotation of the threaded bar 14 with respect to an axis parallel to the coupling axis 15 corresponds to a translation of the switching actuator 6, and therefore of the threaded nut wall 16, with respect to the support frame 3 along an axis parallel to the coupling axis 15.

[0053] The threaded bar 14 is rotatable with respect to the support frame 3, around the coupling axis 15, but it is not translatable with respect to the support frame 3 along the coupling axis 15.

[0054] Vice versa, the threaded nut wall 16 of the switching actuator 6 is translatable with respect to the support frame 3 along the coupling axis 15 following a rotation of the threaded bar 14, but it is not rotatable with respect to the support frame 3, around the coupling axis 15.

[0055] Advantageously, such a threaded connection between the support frame 3 and the switching actuator 6 ensures an effective and accurate movement of the switching actuator 6 along the coupling axis 15.

[0056] According to an embodiment, the switching actuator 6 comprises a coupling portion 17. The coupling portion 17 faces the plurality of hoppers 4.

[0057] According to an embodiment, each hopper 4 of the plurality of hoppers 4 comprises an opening edge 18. The opening edge 18 of the respective hoppers 4 faces the switching actuator 6.

[0058] The opening edge 18 defines a containment compartment 31 adapted to contain the powders 5.

[0059] Specifically, the powders 5 are loadable into the containment compartment 31 of hopper 4 through the opening edge 18.

[0060] According to an embodiment, the opening edge 18 extends over a plane transverse to the coupling axis 15.

[0061] According to an embodiment, the coupling portion 17 of the switching actuator 6 faces the opening edge 18 of the respective hoppers 4.

[0062] According to an embodiment, the removable coupling means 9 are positioned on the coupling portion 17 of the switching actuator 6 and on the opening edge 18 of the hoppers 4.

[0063] According to an embodiment, the removable coupling means 9 comprise at least a first magnet 19 and a second magnet 20, which are subject to a mutual force of magnetic attraction.

[0064] According to an embodiment, the first magnet 19 is positioned on the coupling portion 17.

[0065] Moreover, the second magnet 20 is positioned on the opening edge 18 of the hoppers 4.

[0066] Thereby, the first magnet 19 and the second magnet 20 face each other.

[0067] According to a preferred embodiment, the second magnet 20 comprises at least one magnetic band, preferably a plurality of magnetic bands connected to the opening edge 18 of the respective hoppers 4.

[0068] According to an embodiment, the second magnet 20 comprises two parallel magnetic bands, preferably positioned at the short edges of the opening edge 18.

[0069] According to an embodiment, the coupling portion 17 comprises a coupling plate 21. The coupling plate 21 extends over a plane transverse to the coupling axis 15. Preferably, the coupling plate 21 is parallel and faces the opening edges 18 of the hoppers 4.

[0070] According to this embodiment, the at least a first magnet 19 is positioned on the coupling plate 21 , facing the opening edges 18.

[0071] According to an embodiment, the at least a first magnet 19, preferably a plurality of first magnets 19, is positioned so as to correspond to the at least one magnetic band of the respective hoppers 4.

[0072] Advantageously, it is possible, by means of a hopper system 1 thus configured, to pick a hopper 4 from the plurality of hoppers 4 positioned in a resting position by moving the switching actuator 6 along the coupling axis 15, towards the hoppers 4, so as to couple the coupling portion 17 of the switching actuator 6 at the opening edge 18 of hopper 4, preferably by means of the force of magnetic attraction between the first magnet 19 and the second magnet 20.

[0073] Hopper 4 thus picked is then transportable to a dispensing position. According to an embodiment, the dispensing position is positioned along the lower coupling axis 15 with respect to the resting position. As a result, the movement of hopper 4 from the resting position to the dispensing position occurs by means of a movement of the switching actuator 6 along the coupling axis 15 approaching against hopper 4. Following the coupling between switching actuator 6 and hopper 4, the switching actuator 6 continues the movement along the coupling axis 15, pressing hopper 4 towards the dispensing position and finally releasing hopper 4 in the dispensing position.

[0074] Next, hopper 4 positioned in the dispensing position is again pickable by the switching actuator 6, preferably by means of the force of magnetic attraction between the first magnet 19 and the second magnet 20, and repositionable in the resting position by means of a movement of the switching actuator 6 along the coupling axis 15, but in the opposite direction.

[0075] Optionally, after repositioning hopper 4 in the resting position, the plurality of hoppers 4 is translatable along the translation axis 8 so as to position a different hopper 4below the switching actuator 6, and in particular, the coupling plate 21 of the switching actuator 6, so as to allow a movement of the different hopper 4 into the dispensing position, according to the movement steps described above.

[0076] Advantageously, it is possible, by means of the synergetic movement of the switching actuator 6 along the coupling axis 15 and the plurality of hoppers 4 along the translation axis 8, to replace hopper 4 positioned in the dispensing position with different hoppers 4, containing different powders 5, and thus print three-dimensional items with different metal materials or colors in a controlled, easy and quick manner.

[0077] According to an embodiment, the first magnet 19 is an electromagnet. According to an embodiment, the electromagnet is electrically feedable by means of a respective feeding system.

[0078] Advantageously, by activating the electromagnet 19 positioned on the switching actuator 6, it is possible to pick hopper 4 from the resting position and transport it to the dispensing position. Hopper 4 is then releasable in the dispensing position by deactivating the electromagnet 19. Next, it is possible to pick hopper 4 from the resting position and reposition it in the dispensing position by activating the electromagnet 19. Hopper 4 is then releasable in the resting position by deactivating the electromagnet 19.

[0079] According to an embodiment, the support frame 3 comprises at least one rail 22, preferably a plurality of rails 22.

[0080] Rail 22 extends in a direction parallel to the translation axis 8.

[0081] According to an embodiment, carriage 7 is slidably connected to rail 22. Thereby, carriage 7 is translatable along the translation axis 8 with respect to the support frame 3 and rail 22.

[0082] According to an embodiment, transmission 13 comprises a toothed pulley 23 and an opposite return pulley 24.

[0083] The toothed pulley 23 and the return pulley 24 are positioned along the translation axis 8 opposite to each other with respect to carriage 7.

[0084] Moreover, transmission 13 comprises a toothed belt 25 wound on the toothed pulley 23 and the return pulley 24.

[0085] Moreover, carriage 7 is connected to the toothed belt 25.

[0086] Advantageously, carriage 7, and therefore the plurality of hoppers 4, are movable along the translation axis 8 by means of the toothed belt 25 connected to the toothed pulley 23 and the return pulley 24.

[0087] Thereby, it is possible to position different hoppers 4 at the switching actuator 6 by moving the hoppers 4 along the translation axis 8, and therefore allow a couplingbetween the switching actuator 6 and a different hopper 4 positioned at the switching actuator 6.

[0088] According to a preferred embodiment, the hopper system 4 comprises a total of four hoppers 4, adjacent to one another along the translation axis 8 when in the resting position.

[0089] Advantageously, the hopper system 1 thus configured can contain four different powders 5 inside the respective four hoppers 4, and therefore use up to four different powders 5 for printing a three-dimensional item.

[0090] According to an embodiment, each hopper 4 comprises a dispensing opening 28. Preferably, the dispensing opening 28 is positioned opposite to the opening edge 18.

[0091] According to an embodiment, each hopper 4 comprises a filter wall 27. The filter wall 27 is positioned at the dispensing opening 28.

[0092] The filter wall 27 is configured to prevent a discharge of the powders 4 from the dispensing opening 28 in the absence of shaking hopper 4.

[0093] According to an embodiment, the hoppers 4 described above can be positioned to replace a binder jetting machine hopper by means of the switching actuator 6. As a result, the original binder jetting machine hopper is replaceable with one of the hoppers 4 described above.

[0094] According to a further embodiment, the aforementioned hoppers 4 are insertable into a binder jetting machine hopper by means of the switching actuator 6. As a result, according to this embodiment, the dispensing position of the hoppers 4 is located inside the binder jetting machine hopper.

[0095] Advantageously, the hopper system 1 described above allows retrofitting the binder jetting machines, giving such machines the possibility of selectively dispensing powders 5 of different metal materials or colors and thus making three-dimensional items of different metal materials or colors, by positioning and cyclically replacing the hoppers 4 of the hopper system 1 inside the binder jetting machine hopper.

[0096] According to a further aspect of the invention, a binder jetting machine 2 comprises a hopper system 1 as described above. The hopper system 1 is configured to deposit and distribute powders 5 on a printing plane 29 of machine 2.

[0097] According to an embodiment, machine 2 comprises a main hopper 30. The main hopper 30 is separate from the hoppers 4 of the hopper system 1 .

[0098] According to an embodiment, each of the hoppers 4 is positionable in machine 2 to replace the main hopper 30. Specifically, machine 2 comprises a filter positioned at the dispensing opening of the main hopper 30. According to an embodiment, the filter ofmachine 2 remains positioned fastened to machine 2, while the main hopper 30 is replaced with one of the hoppers 4, which are positionable at the filter of machine 2.

[0099] According to a further embodiment, the hopper system 1 is configured to selectively insert the hoppers 4 into the main hopper 30 so as to dispense powder 5 contained in hopper 4 inserted in the main hopper 30, on the printing plane 29. According to this embodiment, the hoppers 4 are movable from a resting position, outside the main hopper 30, to a dispensing position, inside the main hopper 30.

[0100] According to an embodiment, an ultrasound shaker 26 is positioned at the dispensing position, preferably connected to the main hopper 30 or to the hoppers 4.

[0101] Specifically, machine 2 comprises the ultrasound shaker 26.

[0102] The ultrasound shaker 26 is configured to shake the hoppers 4 by means of an ultrasound vibration.

[0103] Preferably, the ultrasound shaker 26 is positioned at the dispensing position of the hoppers 4 so as to allow powder 5 to be dispensed.

[0104] Advantageously, powder 5 contained in the respective hopper 4 can cross the filter wall 27 and be dispensed through the dispensing opening 28 by means of the ultrasound vibration actuated by the ultrasound shaker 26.

[0105] With added advantage, a hopper system 1 thus configured allows dispensing the powders 5 in a controlled manner. In fact, while the hoppers 4 remain in the resting position and during the movement of the hoppers 4 from the resting position to the dispensing position, the filter wall 27 prevents the powders 5 from crossing the respective dispensing opening 28, preventing an undesired discharging of powder 5. When hopper 4 is in the dispensing position, the action of the ultrasound shaker 26 allows dispensing the powder 5 from hopper 4.

[0106] Obviously, those skilled in the art will be able to make changes or adaptations to the present invention, without however departing from the scope of the following claims.REFERENCE NUMERALS1 . Hopper system2. Machine3. Support frame4. Hoppers5. Powders6. Switching actuator7. Carriage8. Translation axis9. Removable coupling means10. Actuation system11 . Electronic processing unit12. Electric motor13. Transmission14. Threaded bar15. Coupling axis16. Threaded nut wall17. Coupling portion18. Opening edge19. First magnet20. Second magnet21 . Coupling plate22. Rail23. Toothed pulley24. Return pulley25. Toothed belt26. Ultrasound shaker27. Filter wall28. Dispensing opening29. Printing plane30. Main hopper31 . Containment compartment

Claims

CLAIMS1. A hopper system (1 ) for a binder jetting machine (2), comprising:- a support frame (3), fastenable to the machine (2);- a plurality of hoppers (4), wherein each hopper (4) is adapted to contain binder jetting powders (5);- a switching actuator (6), wherein the switching actuator (6) is configured to pick a hopper (4) of the plurality of hoppers (4) positioned in a resting position and transport the picked hopper (4) from the resting position to a dispensing position.

2. A hopper system (1 ) according to claim 1 , comprising a carriage (7) connected to the support frame (3) so as to be translatable with respect to the support frame (3) along a translation axis (8), wherein, when positioned in the resting position, the hoppers (4) are adjacent to one another along a direction parallel to the translation axis (8), wherein the plurality of hoppers (4) is connected to the carriage (7) so as to be translatable with respect to the support frame (3) along the translation axis (8), wherein the switching actuator (6) is connected to the support frame (3) so as to be translatable with respect to the support frame (3) along a coupling axis (15), wherein the coupling axis (15) is transverse to the translation axis (8).

3. A hopper system (1 ) according to claim 1 or 2, comprising removable coupling means (9) positioned on the plurality of hoppers (4) and on the switching actuator (6), wherein the removable coupling means (9) are configured to allow a coupling or detachment, and vice versa, between the switching actuator (6) and a respective hopper (4) of the plurality of hoppers (4).

4. A hopper system (1 ) according to one of the preceding claims, comprising an actuation system (10) configured to actuate a translation of the plurality of hoppers (4) with respect to the support frame (3) and configured to actuate a translation of the switching actuator (6) with respect to the support frame (3), wherein the hopper system (1 ) comprises an electronic processing unit (1 1 ) configured to control the actuation system (10), wherein the actuation system (10) comprises an electric motor (12) and a transmission (13), wherein the transmission (13) is connected to the electric motor (12) and to theswitching actuator (6) to transmit a movement originating from the electric motor (12) to the switching actuator (6), and wherein the transmission (13) is connected to the electric motor (12) and to the plurality of hoppers (4), preferably to the carriage (7), to transmit a movement originating from the electric motor (12) to the plurality of hoppers (4), preferably to the carriage (7).

5. A hopper system (1) according to claim 2, wherein the support frame (3) comprises at least one threaded bar (14), preferably a plurality of threaded bars (14), wherein the threaded bar (14) extends in a direction parallel to the coupling axis (15), wherein the switching actuator (6) comprises at least one threaded nut wall (16), wherein the at least one threaded nut wall (16) of the switching actuator (6) extends in a direction parallel to the coupling axis (15), wherein the at least one threaded nut wall (16) of the switching actuator (6) is coupled to the at least one threaded bar (14) of the support frame (3) by means of a threaded connection, and wherein the switching actuator (6) and the support frame (3) are connected so that a rotation of the threaded bar (14) with respect to an axis parallel to the coupling axis(15) corresponds to a translation of the switching actuator (6) and the threaded nut wall(16) with respect to the support frame (3) along an axis parallel to the coupling axis (15).

6. A hopper system (1 ) according to one of the preceding claims, wherein the switching actuator (6) comprises a coupling portion (17) facing the plurality of hoppers (4), wherein each hopper (4) of the plurality of hoppers (4) comprises an opening edge (18) facing the switching actuator (6), wherein the opening edge (18) defines a containment compartment (31 ) adapted to contain the powders (5), wherein the opening edge (18) extends over a plane transverse to the coupling axis (15), wherein the coupling portion (17) of the switching actuator (6) faces the opening edge (18) of the respective hoppers (4), wherein the removable coupling means (9) are positioned on the coupling portion (17) of the switching actuator (6) and on the opening edge (18) of the hoppers (4), wherein the removable coupling means (9) comprise at least a first magnet (19) and a second magnet (20), which are subject to a mutual force of magnetic attraction, and wherein the first magnet (19) is positioned on the coupling portion (17) and wherein the second magnet (20) is positioned on the opening edge (18) of the hoppers (4).

7. A hopper system (1 ) according to claim 6, wherein the second magnet (20) comprises at least one magnetic band, preferably a plurality of magnetic bands connected to the opening edge (18) of the respective hoppers (4), wherein the coupling portion (17) comprises a coupling plate (21 ) extending over a plane transverse to the coupling axis (15), wherein the at least a first magnet (19) is positioned on the coupling plate (21 ), facing the opening edges (18) so as to correspond to the at least one magnetic band of the respective hoppers (4), and wherein the first magnet (19) is an electromagnet.

8. A hopper system (1) according to claim 2, wherein the support frame (3) comprises at least one rail (22) extending in a direction parallel to the translation axis (8), wherein the carriage (7) is slidably connected to the rail (22) so that the carriage (7) is translatable along the translation axis (8) with respect to the support frame (3) and the rail (22), wherein the hopper system (1 ) comprises a transmission (13) comprising a toothed pulley (23) and an opposite return pulley (24), wherein the toothed pulley (23) and the return pulley (24) are positioned along the translation axis (8) opposite to each other with respect to the carriage (7), and wherein the transmission (13) comprises a toothed belt (25) wound on the toothed pulley (23) and the return pulley (24), and wherein the carriage (7) is connected to the toothed belt (25), and wherein the carriage (7) and the plurality of hoppers (4) are movable along the translation axis (8) by means of the toothed belt (25) connected to the toothed pulley (23) and the return pulley (24).

9. A hopper system (1 ) according to one of the preceding claims, comprising four hoppers (4), adjacent to one another along the translation axis (8) when in resting position, and / or wherein each hopper (4) comprises a dispensing opening (28), preferably positioned opposite to the edge opening (18), wherein each hopper (4) comprises a filter wall (27) positioned at the dispensing opening (28), wherein the filter wall (27) is configured to prevent a discharge of the powders (4) from the dispensing opening (28) in the absence of shaking of the hopper (4),and / or wherein the hoppers (4) are positionable in a machine (2) replacing a binder jetting machine hopper, or wherein the hoppers (4) are insertable, by means of the switching actuator (6), into a binder jetting machine hopper.

10. A binder jetting machine (2), comprising a hopper system (1 ) according to one of the preceding claims, wherein the hopper system (1 ) is configured to deposit and distribute powders (5) on a printing plane (29) of the machine (2).

11. A binder jetting machine (2) according to claim 10, comprising a main hopper (30), separate from the hoppers (4) of the hopper system (1 ), wherein the hopper system (1 ) is configured to selectively position the hoppers (4) in the machine (2) to replace the main hopper (30) so as to dispense the powder (5) contained in the hopper (4) on the printing plane (29), or wherein the hopper system (1 ) is configured to selectively insert the hoppers (4) into the main hopper (30) so as to dispense the powder (5) contained in the hopper (4) inserted into the main hopper (30) on the printing plane (29), wherein the hoppers (4) are movable from a resting position, outside the main hopper (30), to a dispensing position, inside the main hopper (30), and wherein the hoppers (4) are movable from a resting position, outside the main hopper (30), to a dispensing position, inside the main hopper (30), wherein the machine (2) comprises an ultrasound shaker (26) configured to shake the hoppers (4) by means of an ultrasound vibration, wherein, preferably, the ultrasound shaker (26) is positioned at the dispensing position of the hoppers (4).

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