阅读说明：本技术 3d打印机 (3D printer ) 是由 梅丽莎·斯诺弗伯顿 马丁·卡奇普尔 于 2021-03-24 设计创作，主要内容包括：一种用于生产消耗品的3D打印机,所述3D打印机包括用于分配材料的设备,该设备包括：第一注射器,第一注射器具有用于容纳材料的主体、用于从主体分配材料的喷嘴和用于控制主体中的压力的柱塞；柱塞机构,该柱塞机构联接到柱塞；主体机构,该主体机构联接到主体；以及致动器,该致动器被布置成使柱塞机构相对于主体机构在第一方向上移动,以增大第一注射器主体中的压力来分配材料,且使柱塞机构相对于主体机构在第二方向上移动,以减小注射器主体中的压力,来阻止材料的分配。(A 3D printer for producing a consumable, the 3D printer comprising an apparatus for dispensing material, the apparatus comprising: a first syringe having a body for containing a material, a nozzle for dispensing the material from the body, and a plunger for controlling pressure in the body; a plunger mechanism coupled to the plunger; a body mechanism coupled to the body; and an actuator arranged to move the plunger mechanism relative to the body mechanism in a first direction to increase pressure in the first syringe body to dispense material and to move the plunger mechanism relative to the body mechanism in a second direction to decrease pressure in the syringe body to prevent dispensing of material.)

1. A 3D printer for producing a consumable, the 3D printer comprising an apparatus for dispensing material, the apparatus comprising:

a first syringe having a body for containing a material, a nozzle for dispensing the material from the body, a plunger for controlling pressure in the body, and a syringe handle coupled to the plunger and arranged to move the plunger;

a plunger mechanism releasably coupled to the plunger,

and

an actuator arranged to move the plunger relative to the body in a first direction to increase pressure in the body to dispense the material and to move the plunger relative to the body in a second direction to decrease the pressure in the body to prevent dispensing of the material,

wherein the plunger mechanism comprises: a plate arranged to exert a force on the syringe handle in the first direction; and a first retention plate having a slot for receiving and retaining the syringe handle and exerting a force on the syringe handle in the second direction.

2. The 3D printer of claim 1, further comprising a plunger coupling actuator arranged to move the plunger mechanism to couple the plunger mechanism to the plunger.

3. The 3D printer of claim 1, the 3D printer further comprising a body mechanism releasably coupled to the body.

4. The 3D printer of claim 3, wherein the body mechanism comprises an electromagnet.

5. The 3D printer of claim 1, wherein the plunger mechanism comprises a snap-fit coupling.

6. The 3D printer of claim 1, wherein the plunger mechanism comprises a lead screw.

7. The 3D printer of claim 1, the 3D printer further comprising a second syringe having a body for containing a second material, a nozzle for dispensing the second material, and a plunger for controlling pressure in the second syringe body exerted on the second material,

wherein the plunger mechanism is coupled to a plunger of the second syringe and the body mechanism is coupled to the second syringe body such that pressure in the second syringe body varies with pressure in the first syringe body.

8. The 3D printer of claim 7, wherein each of the first syringe and the second syringe comprises a handle, and

wherein the plunger mechanism includes at least two retaining plates, each retaining plate having a slot for receiving and retaining one of the syringe handles.

9. The 3D printer of claim 7, wherein the first and second syringes are arranged to dispense material onto first and second print positions, respectively.

10. The 3D printer of claim 1, further comprising a third syringe having a body for containing a third material, a nozzle for dispensing the third material, and a plunger for controlling pressure in the body exerted on the third material,

wherein the plunger mechanism is coupled to the plunger of the third syringe to move the plunger of the third syringe with the plunger of the first syringe.

11. The 3D printer of claim 10, wherein each of the first syringe, the second syringe, and the third syringe comprises a handle, and

wherein the plunger mechanism comprises at least two retention plates including a first retention plate having two slots, each slot for receiving and retaining each of the syringe handles.

12. The 3D printer of claim 1, further comprising a plate containing a first printing position for receiving and supporting material dispensed from the first injector, wherein the plate is rotatable relative to the first injector.

13. The 3D printer of claim 12, wherein the plate is rotatable to enable the first injector to be aligned with a second printing position at a point in time and the second syringe to be aligned with the first printing position at a point in time.

14. A method of depositing a material using a 3D printer, the method comprising:

releasably coupling a syringe to the 3D printer, the syringe having a body for containing a material, a nozzle for dispensing the material, and a plunger for controlling pressure in the body,

depositing the material from the injector nozzle onto a first print position by moving a plunger of the injector in a first direction with a plunger mechanism to increase pressure in the injector body,

moving a plunger of the syringe in a second direction opposite the first direction with the plunger mechanism to reduce pressure in the syringe body to prevent deposition of the material;

wherein the syringe further comprises a handle coupled to the plunger, and the method further comprises mounting the syringe in a retaining mechanism by sequentially performing the steps of:

applying a force to the syringe handle using a first plate of a retaining mechanism, the first plate of the retaining mechanism located on a first side of the syringe handle; and

mounting a second plate of the retention mechanism on a second side of the syringe handle, the second side being opposite the first side.

15. The method of claim 14, wherein the syringe is a first syringe, and

the method further comprises the following steps:

providing a second syringe having a body for containing a second material, a nozzle for dispensing a fluid, and a plunger for controlling pressure in the body,

depositing material from the second syringe nozzle onto a second printing location by moving a plunger of the second syringe in the first direction with the retaining mechanism to increase pressure in the second syringe body while the first syringe handle is moved,

moving a plunger of the second syringe in a direction opposite the first direction to reduce pressure in the second syringe body to prevent deposition of the material.

16. The method of claim 14, further comprising: depositing material from the first injector nozzle onto the second printing location by moving a plunger of the first injector in the first direction to create a positive pressure in the first injector body.

17. The method of claim 14, further comprising moving the first print position and/or the second print position by rotating a plate containing the first print position.

Technical Field

The application generally belongs to the technical field of 3D printing and forming, and particularly relates to a 3D printer.

Background

Machines exist for dispensing pharmaceutical products. However, existing machines produce large quantities of the same product and rely on dispensers, such as pharmacists, to schedule the medication for individual consumers. Therefore, a device for alleviating the burden on the distributor is required.

Disclosure of Invention

According to a first aspect of the present invention, there is provided a 3D printer for producing a consumable, the 3D printer comprising apparatus for dispensing material, the apparatus comprising: a first syringe having a body for containing a material, a nozzle for dispensing the material from the body, and a plunger for controlling pressure in the body; a plunger mechanism coupled to the plunger; a body mechanism coupled to the body; and an actuator arranged to move the plunger mechanism relative to the body mechanism in a first direction to increase pressure in the syringe body to dispense the material and to move the plunger mechanism relative to the body mechanism in a second direction to decrease the pressure in the syringe body to prevent dispensing of the material.

Thus, the 3D printer according to the first aspect of the invention is arranged to print consumable items such as pharmaceuticals or healthcare supplements. Reducing the pressure in the syringe body, for example creating a negative pressure (which may only be temporary), may reduce unnecessary material dispensing of the syringe nozzle between printing operations and thereby may enable more accurate printing while reducing waste.

Thus, a 3D printer according to embodiments of the present invention is able to dispense fast curing materials in a controlled manner, thereby controlling the shape of the consumable items produced, while being able to produce multiple layers of consumable items quickly and consistently. In contrast to machines that simply dispense doses of flowable material in the form of pellets, 3D printers according to embodiments of the present invention may arrange the same volume of material into a shape having a larger surface area than the pellets, thereby enabling the flowable material to solidify more quickly in preparation for the next layer to be dispensed thereon. The increased surface area may also help the applied layer adhere to the underlying layer.

The 3D printer may further include a plate containing a first printing position for receiving and supporting material dispensed from the first injector, the plate being rotatable relative to the first injector. This may cause material to be deposited by the first injector and then the printing position may be moved to cause material to be deposited via the second injector.

The plunger mechanism may be releasably coupled to the plunger, and/or the body may be releasably coupled to the body mechanism. This may allow the 3D printer to be more efficiently reused to deposit different materials from different syringes.

The body mechanism may include an electromagnet that can be switched on and off to allow the body to be uncoupled from the body mechanism. The body may comprise a flange arranged to be received in the body means.

The syringe may comprise a handle coupled to the plunger, and the plunger mechanism may comprise a plate arranged to exert a force on the syringe handle in a direction towards the syringe body. This may provide an arrangement for applying force evenly on the syringe handles, and if there are multiple syringes, the plate may move all of the syringe handles evenly to distribute material evenly.

The plunger mechanism may include a retention plate having a slot for receiving and retaining the syringe handle. This may allow the syringe to be easily mounted in and securely held by the holding mechanism.

The plunger mechanism may further comprise a snap-fit coupling for coupling the plunger of the syringe to the retaining mechanism. This can provide a simple means for mounting the syringe in the retaining mechanism.

The plunger mechanism may comprise a lead screw. This may allow for precise control of the holding mechanism, and thus the syringe handle, for example using a stepper motor, optionally a geared stepper motor.

The 3D printer may further include a second syringe having a body for containing a second material, a nozzle for dispensing the second material, and a plunger for controlling pressure in the body exerted on the second material, wherein the plunger mechanism is coupled to the plunger of the second syringe and the body mechanism is coupled to the body of the second syringe such that pressure in the second syringe body varies with pressure in the first syringe body. This may allow a variety of different materials to be dispensed from the syringe, and the use of a common retaining mechanism may enable a uniform volume of material to be deposited, and also enable simpler control of the syringe.

The first and second syringes may each include a handle, and the retaining mechanism may include at least two retaining plates, each retaining plate having a slot for receiving and retaining a syringe handle. By this arrangement, a simple holding device for resiliently holding a plurality of syringes is provided. Each syringe may be held at the end of a slot.

The first and second injectors may be arranged to dispense different materials onto the first and second print positions respectively. Thus, the flowable material in the first body may be different from the flowable material in the second body. This may allow a range of products to be produced, each of which may include more than one material, in a shorter amount of time.

The plate may be rotatable such that the first injector may be aligned with the second printing position at a point in time and the second injector may be aligned with the first printing position at a point in time. This may lead to a more efficient printing process for producing products with a variety of different materials.

The apparatus may comprise a controller arranged to deposit the flowable material from the injector nozzle onto a first print position by moving the plunger of the injector in a first direction with the plunger mechanism to increase the pressure in the injector body, the plunger of the injector being moved in a second direction, opposite the first direction, with the plunger mechanism so as to reduce the pressure in the injector body and prevent deposition.

The first and second print positions may be located within a print zone, the print zone may include a plate, and a rotation device may be mechanically coupled to the plate to rotate the plate about a Z-axis. Thus, the rotating means may be arranged to rotate a portion of the print bed on which the print head comprising the injector is arranged to print. This may be advantageous because the print zone plate may be significantly lighter than the liquid dispenser and the portion of the printhead carrying them, which means that smaller, less expensive motors or the like may be utilized, thereby improving energy and thermal efficiency. It may also allow the print bed to be rotated and aligned more accurately.

The translation device may be arranged to move the print bed relative to the print head along the Z-axis. This enables the distance between the tip of the dispenser nozzle and the printing position on the print bed to be increased when adding a layer of consumable items, thereby enabling the nozzle to be always close to the top surface of the consumable item when the consumable items accumulate.

Each injector may be arranged to be mounted within or on a printhead arranged to support a plurality of injectors. This enables ubiquitous syringes (e.g., food grade or pharmaceutical grade stainless steel syringes) to be used in the printing process.

The printhead may include: a block having a plurality of block apertures extending through the block; and a syringe support arranged to receive and hold the syringe to define a regular polygon, the syringe support being removably coupled to the block. The block may be part of the body mechanism.

The block may include a heating means operable to heat the material in the syringe. The heating block may be used to heat the material in the dispenser to assist the material being extruded by the actuator device during a dispensing cycle. The thickness of the block in the Z-axis may be at least half the length of the body of the injector to provide a large thermal coupling area. The heating means may comprise a resistive wire or hot water conduit embedded in a metal block.

The syringe support, which may be part of the body mechanism, may comprise: a first backer plate having a plurality of support apertures, each support aperture being arranged to receive a syringe and being dimensioned such that at least some portion of the body of the syringe can pass through the support aperture but the radially enlarged flange of the syringe body cannot pass through the support aperture; a second support plate having a plurality of support apertures, each support aperture being arranged to receive a syringe and being dimensioned such that at least some portion of the syringe body can pass through the support aperture but the radially enlarged flange of the syringe body cannot pass through the support aperture, the support apertures being arranged to define a regular polygon; and a coupling formation arranged to enable coupling of a first support plate to the block by means of a second support plate located between the block and the first support plate. This provides a means by which a plurality of syringes can be quickly and conveniently coupled together in a regular polygonal configuration in preparation for insertion into a print head.

The coupling configuration may include a region of ferromagnetic material and the block includes a plurality of electromagnets positioned in alignment with the coupling region when the syringe support is positioned on the block and operable to magnetically couple the syringe support to the block. The coupling formation may comprise a disc extending from the lower surface of the first plate a distance that aligns a free axial face of the disc with the lower surface of the second plate when the plurality of plates are pressed together with the syringe flange therebetween.

The flat plate may have: a drive face having a plurality of syringe handle locations arranged in said regular polygon and a pair of parallel support tracks defining a channel therebetween and having a flange portion spaced from said first plate and extending toward each other, said plurality of syringe handle locations being defined between support tracks; a first retention plate and a second retention plate, each retention plate including a plurality of slots extending into the retention plate from a first edge and having an arcuate end face that overlaps the syringe plunger to grasp the syringe plunger when the first retention plate and the second retention plate are inserted into opposite ends of the channel and the syringe plunger is in the syringe plunger position. One or more linear actuators may be coupled between the plate and the block to move the plate linearly toward the block to dispense liquid from the syringe. This provides a means by which a plurality of syringes located in a syringe support can be quickly and conveniently coupled to a print head.

The print bed may include a plurality of print zones. Thus, once a first set of consumable items has been printed on the first print zone, the print bed can be moved along the X-axis using the translation device, such that the process can be repeated to print another set or sets of consumable items at one or more other print zones on the print bed. This may enable a greater number of consumable items to be printed in a rapid manner without increasing the size, weight, and/or complexity of the printhead.

The print head may be arranged to position the nozzles to define a seven-sided polygon, and each print zone to position a print position to define a seven-sided polygon. The print bed may be comprised of four print zones arranged linearly along the print bed, wherein the axis of each print zone intersects the longitudinal axis of the print bed. This may provide an arrangement that is particularly suitable for printing pharmaceuticals or healthcare supplements.

The controller may be further configured to cause the 3D printer to perform the steps of: operating the actuator means to dispense liquid from each nozzle onto a respective print position with the first Z axis aligned with the second Z axis: operating a rotation device to cause relative rotation between the print zone and the print head to place each print position in registration with a different one of the nozzles; and operating the actuator means to dispense liquid from each nozzle onto a respective print position. This process may be repeated a number of times, preferably the same number of times as the number of dispensers, so that multiple layers of consumable items having the composition provided by each dispenser may be printed.

The controller may be further configured to cause the 3D printer to perform the steps of: after each step of operating the actuator means to dispense liquid from each liquid dispenser to a respective print position, the print bed is moved in the Z direction away from the print head by an amount corresponding to the thickness of the liquid dispensed at the print position in the Z axis.

The controller may be further configured to operate the actuator device to dispense liquid from each liquid dispenser to a respective print position while moving the print bed in the X and Y directions to form a closed loop shape.

The flowable material dispenser may be filled with any of the compositions disclosed in WO 2016113318 a1, WO 201121822 a1 or WO 2017/032689 a 1. The dispenser may be filled with a fast curing composition (optionally a fast curing gel). This may increase manufacturing speed. The material may be a liquid.

In an alternative embodiment, the apparatus may be a dispenser for manufacturing consumables, not necessarily a 3D printer.

According to a second aspect of the present invention, there is provided a method of depositing a material using a 3D printer, the method comprising: coupling a syringe to the 3D printer, the syringe having a body for containing a material, a nozzle for dispensing the material, and a plunger for controlling pressure in the body; depositing the material from the injector nozzle to a first print position by moving the plunger of the injector in a first direction with a plunger mechanism to increase pressure in the injector body; moving the plunger of the syringe in a second direction opposite the first direction with the plunger mechanism so as to reduce the pressure in the syringe body to prevent deposition of the material.

Using this method, unwanted material deposition from the injector nozzle may be reduced. In particular, material leakage or deposition during movement of the printing position may be reduced. Thus, more accurate printing can be achieved, resulting in higher quality products and less material waste.

The method may further comprise mounting the syringe in a retaining mechanism by sequentially performing the steps of: applying a force to a syringe handle using a first plate of a retention mechanism on a first side of the syringe handle; mounting a second plate of the retention mechanism on a second side of the syringe handle opposite the first side. This may allow the use of a retaining mechanism with very low tolerances and thus improve the control accuracy of the syringe handle, thereby reducing lost motion.

The syringe may be a first syringe, and the method may further comprise: providing a second syringe having a body for containing a second material, a nozzle for dispensing a fluid, and a plunger for controlling pressure in the body; depositing material from the second syringe by moving a plunger of the second syringe in the first direction with the retaining mechanism to increase pressure in the syringe body while moving with a first syringe handle; moving a plunger of the second syringe in a direction opposite the first direction so as to reduce pressure in the second syringe body to prevent deposition of the material. This may allow multiple materials to be dispensed from the syringe simultaneously and thereby provide a simple and efficient method of producing consumables.

The method may further comprise depositing material from the first injector nozzle onto a second printing location by moving a handle of the first injector in the first direction to generate positive pressure in the first injector body. This may allow for the production of consumables having more than one material.

The movement of the first print position may be due to rotation of a plate containing the first print position. This may enable higher 3D printing accuracy since rotation may be performed more accurately than linear movement. Rotation may also enable better utilization of the syringe.

Drawings

Certain embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings, in which:

FIGS. 1a and 1b are perspective and side views of a 3D printer according to an embodiment of the present invention;

FIGS. 2a, 2b and 2c are perspective, top and side views, respectively, of a movable portion of a print bed of the 3D printer of FIG. 1;

FIG. 3 is a side view showing internal components of a print head of the 3D printer of FIG. 1;

figures 4a and 4b are perspective and side views respectively of a syringe held in a syringe support of the 3D printer of figure 1;

FIG. 5 is a schematic diagram showing a syringe of the 3D printer of FIG. 1 loaded into a syringe support;

FIG. 6 is a schematic diagram showing the syringe support of the 3D printer of FIG. 1 mounted on a block of a printhead;

FIG. 7 is a perspective view of the underside of the retaining mechanism of the actuator device of the 3D printer of FIG. 1;

FIG. 8 is a lower view of a portion of the drive plate showing the position of the plunger;

fig. 9 is a side view showing the insertion of the holding plate;

10a and 10b are perspective views of a snap-fit coupling for use with the 3D printer of the present invention;

11a and 11b are schematic diagrams showing how a syringe and snap-fit coupling may be installed within a 3D printer of the present invention;

FIG. 12 is a flow chart illustrating a method according to an embodiment of the invention;

FIG. 13 is a side view showing internal components of a printhead of an alternative 3D printer; and

fig. 14a and 14b are side and front views of a single injector mounted in a printhead.

Detailed Description

Fig. 1a and 1b generally illustrate a 3D printer for printing consumable items according to an embodiment of the present invention, the 3D printer being indicated by reference numeral 10. A 3D printer is a device arranged to dispense fast curing material in a controlled manner to control the shape of the product produced.

The 3D printer 10 has a printhead 12 arranged to position the nozzles of a plurality of flowable material dispensers to define a regular polygon about a first Z axis Z1. In this embodiment, the fluid dispenser is an injector arranged to be positioned in a face down manner on the block 14 within the printhead 12.

The 3D printer 10 has an actuator device 16, located in the print head 12 in this embodiment, operable to dispense a portion of material from each material dispenser located in the block 14.

The 3D printer 10 has a print bed comprising four print zones PZ, each print zone PZ comprising a plurality of print positions PL arranged to define a regular polygon about a respective second Z axis Z2.

3D printer 10 has translation means operable to move print bed 18 relative to print head 12 along the X and Y axes. In this embodiment, print bed 18 is slidably mounted on base 20 so as to be movable along the X-axis.

As can be seen from fig. 1a and 1b, the first Z-axis Z1 and the second Z-axis Z2 are vertical and can be offset, and the X-axis and the Y-axis are horizontal and can be perpendicular to each other.

The 3D printer 10 has rotation means operable to cause relative rotation between the print zone PZ and the printhead 12 such that with the first Z axis Z1 aligned with the second Z axis Z2, the actuator means 16 is operable to dispense material from each material dispenser onto a respective print position PL, and thereafter the rotation means is operable to cause relative rotation between the print zone PZ and the printhead 12 to align each print position PL with a different nozzle.

Fig. 2a, 2b and 2c are perspective, top and side views, respectively, of a movable part of a print bed 18 of the 3D printer of fig. 1.

Print bed 18 is supported on a base 20 having an X-motor (not shown) for moving print bed 18 in the X-direction by interacting with X-bearings 30. Print bed has a Z motor 26 for moving print bed 18 in a vertical direction (i.e., along second Z axis Z2) and a Y motor 28 for moving print bed 18 along the Y axis.

Print bed 18 includes a plate 22, with plate 22 forming a print zone PZ. In the disclosed embodiment, four plates 22 form four respective print zones PZ, however, other numbers of plates 22 and print zones PZ may be used. Print zones PZ may be positioned along the top surface of print bed 18 and distributed along the X-axis.

The respective printing zones PZ defined by each plate 22 have a plurality of printing positions PL. Each plate 22 may be rotationally symmetric about their respective second Z-axis Z2, whereby the plates 22 may be rotated and the print position may be changed in position such that when the plates 22 are rotated a predetermined number of degrees, the first print position PL may reach the position of the second print position PL. The plate 22 may be rotated by a rotation motor 24 so as to move the printing position PL. The rotation motor 24 is preferably a stepper motor, more preferably a geared stepper motor, which can provide high rotational accuracy.

Additionally, there may be one or more pins in the base 20 that engage corresponding holes or ramps in the plate 22 when the correct angle of rotation is reached. The pins may lock the plate 22 in place to prevent unwanted rotation of the plate 22 during deposition.

Although fig. 2a and 2b show seven print positions PL per print zone PZ, other numbers of print positions PL are possible on each print zone. The number of print positions PL in each print zone PZ should preferably be the same as the number of injectors supported within printhead 12.

Figure 3 shows an extrusion system for operating a syringe. The extrusion system includes an extrusion plate 34 for pressing on the plunger of the syringe and a retention plate 36 for securing the handle of the syringe. The extrusion plate 34 and the holding plate 36 are movable in the vertical direction along the rail 33, the rail 33 forming a passage therebetween. These components thus form a plunger mechanism for moving the plunger of the syringe. Extrusion motors 32a and 32b are arranged to drive extrusion plate 34 and holding plate 36 vertically to exert a downward force on the plunger of the syringe to dispense material from the syringe.

The system may also include a heating block 14, which heating block 14 may contain a wire or fluid circulation system and be arranged to heat the material within the syringe in order to reduce the viscosity of the material and/or melt the material so that the material may be more easily dispensed from the syringe and a greater range of materials may be dispensed by use of the heating block 14.

Fig. 4a and 4b show the arrangement of the syringe 42 in the body mechanism, but the embodiment extends to apparatus comprising a single syringe. Each syringe has: a syringe body 44, the syringe body 44 being fillable with an edible material to be dispensed; a nozzle 48 for controlling the dispensing of material; and a plunger 46, the plunger 46 being depressible towards the syringe body 44 to extrude material from the nozzle 48. Each syringe may also have a lug 50 extending from the syringe body 44. The lugs 50 may be placed between the two support plates 38, 40. The first support plate 38 may be located above the lugs and the second support plate 40 may be located below the lugs. The first support plate 38 may have coupling formations 38a, the coupling formations 38a being used to hold the first support plate 38 to a block (e.g. a heater block 14 or a non-heater block of the printhead 12).

The arrangement of the first and second support plates 38, 40 and the injectors 42 provides for the injectors 42 to be stably held outside the print head 12 so that these injectors 42 can be quickly and easily inserted into the print head 12 simultaneously.

As shown in FIG. 5, the first backer plate 38 may have support apertures 38b, the support apertures 38b being sized larger than the syringe body 44 and smaller than the lugs 50, and the second backer plate 40 may have second support apertures 40b, the second support apertures 40b also being sized larger than the syringe body 44 and smaller than the lugs 50. This allows the syringe 42 to be inserted through the support apertures 38b, 40b and held in place by the lugs 50 and the support plates 38, 40.

Fig. 6 shows printhead 12 with injector 42 installed. The injector 42 is mounted within the heating block 14 and is held in place by a first support plate 38 and a second support plate (not visible in fig. 6). It can be seen that the coupling formations 38a couple to corresponding coupling formations 52 on the heating block 14. The coupling formations 38a on the first support plate 38 may be ferromagnetic material and the corresponding coupling formations 52 on the heating block 14 may be magnets, preferably electromagnets. The plunger end of injector 42 (not visible in FIG. 6) is positioned below extrusion plate 34 such that extrusion plate 34 may be moved vertically downward to extrude material from injector 42.

Fig. 7 shows a view of the holding plate 36 connected to the flat plate 34 from below (the flat plate 34 may also be referred to as an extrusion plate or a drive plate). It can be seen that the retaining plate 36 can be formed in two parts which can be slid into place along the slide rails 35. The retention plate 36 may include a slot 36a, the slot 36a being slidable into position to retain a plunger 46 of the syringe 42.

Because the syringe handle 46 (also referred to as a syringe plunger) has a portion with a width greater than the width of the slot 36a, the retention plate 36 can exert a force on the syringe handle 46 in a direction away from the syringe body 44.

Figures 8 and 9 show how the two parts of the retaining plate 36 can be slid into place.

The machine may be operated such that extrusion plate 34 is operated to push injector 42 downward such that all plungers contact extrusion plate 34, and retaining plate 36 may be slid into place to clamp onto plungers 46 while plungers 46 are all in contact with extrusion plate 34. This prevents the plunger 46 from being removed from the extrusion plate 34, thereby ensuring stability of the plunger 46. This may also allow a force to be exerted on the plunger 46 in a direction away from the piston body 44 in order to create a negative pressure within the syringe body 44 and thereby prevent extrusion of material.

The 3D printer may be operated such that the print zone PZ is positioned below the injector 42 while the first Z axis Z1 is collinear with the second Z axis Z2 and the print zone PZ is below the nozzle 48. A quantity of material may be extruded from a nozzle 48 of the injector 42 onto a plurality of print positions PL below the injector 42. After the material is extruded, the extrusion may be stopped and the print position may be changed by rotating the plate 22 about the Z axis Z2. Rotation may occur such that after rotation, each print position PL is below a different syringe 42. Subsequently, a second extrusion step may be performed in which further material is extruded from each injector 42 onto the respective printing position PL such that each printing position PL has deposited thereon a different material from a different injector 42, which is deposited on the printing position between each rotation step. This process may be repeated until all necessary material is deposited at each print position PL, for example after full rotation of the print zone PZ. Subsequently, print bed 18 may be moved in the X direction such that a new print zone PZ is positioned below injector 42.

It should also be noted that some of the syringes 42 of the arrangement may not be present or may be empty if the number of different materials that need to be deposited does not exactly match the number of print positions PL. Alternatively, more than one syringe 42 may contain the same material, and it is not necessary that each syringe 42 have a different material.

The syringe 42 may be a sterile syringe suitable for use in food or pharmaceutical manufacturing, and may be filled with a pharmaceutical or food composition for use in manufacturing a food or pharmaceutical supplement (including vitamins and mineral supplements). The flowable material in the syringe may be a solid or may be a gel at room temperature and may become a liquid or less viscous gel when heated by the heating block 14.

During the extrusion step, it is also possible to move the printing bed 18, and therefore the printing zone PZ and the printing position PL, in the X-direction and in the Y-direction, in order to control the deposition pattern and the positional accuracy of the material on each printing position. This may allow for the production of consumables having a particular shape or pattern.

Between each extrusion step, print bed 18 may be moved in the Z-direction, for example, to prevent deposited material from touching injector nozzle 48.

Figure 10a shows a snap-fit connection 80 for connecting the syringe to the retaining mechanism. The snap-fit connection 80 has two portions 82a, 82 b. The first portion 82a has one or more connectors 86, which may be snap-fit connectors, and the second portion 82b may have connectors corresponding to the snap-fit connectors or recesses for receiving the snap-fit connectors. Alternatively, each of the two portions 82a, 82b may have a snap-fit connector, and each portion 82a, 82b may have a recess corresponding to the snap-fit connector on the other portion.

Both portions 82a, 82b contain a groove 84 for receiving the syringe handle 46, the groove 84 being shaped to grip the syringe handle. The snap-fit connector 80 also has a hole on the bottom side for allowing the plunger of the syringe to extend from the snap-fit connector 80 towards the syringe body 44.

The snap-fit connection 80 has at least one protrusion 88 on a top surface, which is opposite the side with the hole. The protrusions are preferably flexible such that the protrusions can be connected into the retaining mechanism by insertion into corresponding holes (not shown) of the retaining mechanism and resiliently retained within the retaining mechanism.

Fig. 10b shows the snap-fit connection 80 formed by the engagement of two portions 82a, 82 b.

Fig. 11a and 11b show how the snap-fit connection 80, when mounted on the handle 46 of the syringe, can be mounted in the retaining mechanism 34 by inserting the protrusions 88 into corresponding holes (not shown) in the retaining mechanism 34.

Through using the snap-fit device, do not need any instrument to install the syringe on the 3D printer, and the retaining mechanism only needs the single board. This may allow for quicker replacement of the syringe.

In any embodiment, a sensor (not shown) may be provided to determine whether a component of the 3D printer has successfully transitioned between the expected stages.

As shown in fig. 1a, a controller C (e.g., a microcontroller, ASIC, or computing device) may be provided to control the operation of the 3D printer. In this embodiment, the controller C is communicatively coupled to all of the motors, actuators, and sensors of the 3D printer.

The flowchart in fig. 12 illustrates a method 100 of operation of printhead 12.

At step 102, printhead 12 is primed while injector 42 is inserted into heat block 14, and print zone PZ is located below injector 42. This step may include moving the print zone PZ into position along the X-axis, and may include an alignment check to ensure that each print position PL is aligned with the nozzle 44 of a particular injector 42. The support plate 38 may also be installed at this stage.

At step 104, extrusion plate 34 may be moved downward, i.e., a small distance toward injector body 44. This ensures that syringe handle 46 is fully in contact with extrusion plate 34. Where a snap-fit connection 80 is used, the snap-fit connection 80 may interlock with the retention mechanism 34 due to the downward movement.

Without the use of the snap-fit connection 80, the retention plate 36 may be inserted at step 106. By moving the extrusion plate 34 downward prior to installing the retention plate 36, a retention mechanism with lower tolerances may be used.

At step 108, material is deposited from injector 42 onto the corresponding print location PL by the continuous movement of extrusion plate 34.

After each deposition step 108, the syringe handles 46 are each retracted a short distance 110, for example, the syringe handles may be retracted a distance between 5 and 10 mm. The distance of retraction may correspond to the volume of fluid in the nozzle such that no fluid remains in the nozzle after retraction.

At step 112, it is checked whether the desired material is deposited at each print position PL within the print zone PZ below the injector 42. If each print position PL has all of the required material, the method moves to step 116, otherwise the method moves to step 114.

At step 114, the print zone PZ is rotated so that each print position PL is aligned with a different injector 42 so that a different material can be deposited onto each print position PL. Another deposition step 104 may then be performed.

At step 116, it is determined whether each print zone PZ on the print bed has deposited material thereon, or whether there are other print zones PZ that require printing. If all of the printed zones PZ have been printed, the method ends at step 120. Otherwise, the method moves to step 118.

At step 118, the print bed is moved in the X direction so that the new print zone PZ is aligned with the injector 42. This step may also include an alignment check to ensure that each print position PL is below the injector 42. Subsequently, a further deposition of material is performed in step 108.

At step 120, the method ends and the printed consumable item may be removed. At this stage, a large number of customized edible products have been produced.

It should be noted that the above-mentioned embodiments illustrate rather than limit the invention, and that those skilled in the art will be able to design many alternative embodiments without departing from the scope of the appended claims. For example, although in the illustrated embodiment the 3D printer 10 is arranged to print a plurality of consumable items, such as pharmaceuticals or healthcare supplements, in parallel, in other embodiments the 3D printer may be arranged to print only a single consumable item during each dispensing cycle.

In another embodiment, the syringe may not have a handle, and the plunger may be coupled directly to a lead screw or the like, and thus may be driven more directly by the actuator.

As noted above, the body mechanism may be secured using magnets, preferably electromagnets, or reversible mechanical fastening means may be used, such as hinges employing an "off-center" arrangement, to hold the syringe injector body in place, and may also incorporate hydraulic cylinders for actuating the body mechanism.

Figure 13 shows a printhead having such an alternative body mechanism. The body mechanism of fig. 13 includes a hydraulic actuator 152, the hydraulic actuator 152 being arranged to actuate a mechanism to hold the support plate 138 in place. The backer plate 138 may thereby hold the syringe body in place, as explained above with reference to fig. 4a, 4b, 5, and 6.

The mechanism may be moved in the opposite direction by actuation of the hydraulic actuator 152, so that the support plate 138 may be released, and the syringe may then be removed from the print head.

Fig. 14a and 14b show a single syringe 42 in a printhead arranged to accommodate only a single syringe. The syringe 42 has: a body 44 releasably retained within a body mechanism formed as a housing around the syringe body 44; and a nozzle 48 extending from the body 44 and arranged to deposit material outwardly from the injector body 44.

The handle 46 of the syringe 42 is held between the extrusion plate 34, which is arranged to exert a force on the syringe handle 46 towards the syringe body 44, and the retention plate 36, which is arranged to exert a force on the syringe handle 46 away from the syringe body 44. Retaining plate 36 may be slidably coupled to extrusion plate 34 such that the retaining plate may be slid horizontally into place to retain syringe handle 46 and slid out of place in the opposite direction to release syringe handle 46 so that syringe 42 may be removed from the print head.