Method and apparatus for forming steady flow of plasticized solid feed material

Abstract

An apparatus for forming a steady flow of plasticized solid feed material, the apparatus includes an in-cylinder piston ram for compacting fragmented solid feed material to form a solid blank of plasticized solid feed material in a cylinder and extruding at least a portion of the solid blank from an outlet end of the cylinder, a transfer path in communication with the outlet end of the cylinder, and a heater associated with at least a portion of the transfer path to plasticize and heat the plasticized solid feed material to a temperature to form the plasticized solid feed material.

Description

Technical Field

[0001] The present invention generally relates to a method and an apparatus for processing a granular solid material to form a plasticized solid feed material. The present invention also relates to a method and an apparatus for forming a plasticized solid feed material from a food product, in particular a confectionery product, and the products obtained thereby. Background Art

[0002] It is also known to provide 3D printing of food such as confectionery. For example, US2012 / 0251688 provides a 3D printer for 3D printing chocolate, wherein the apparatus comprises a reservoir configured to shear and heat chocolate material to provide flowable chocolate, a pump configured to pump the flowable chocolate material from the reservoir, and a print head configured to receive the pumped flowable chocolate material and extrude a portion of the pumped flowable chocolate material to form a three-dimensional solid object.

[0003] Similarly, US2017 / 0259482 describes an apparatus and process for 3D printing chocolate, which includes a printer barrel having a barrel body for containing chocolate printing material, an extruder having a nozzle, and a pneumatic system for enabling pressurized air to push the printing material from the printer barrel to the extruder.

[0004] Thus, known 3D chocolate and confectionery extruders typically utilize a barrel or container of molten and / or tempered chocolate that is pushed via pressure through an extrusion die head that acts as a print head. In such equipment, it can be difficult to control the pressure within the system or equipment, and the use of a barrel or reservoir means that batch processing is typically performed rather than continuous processing.

[0005] Similarly, European Patent No. EP3902405 discloses a 3D printing device, which includes at least one print head, a supply system for continuously supplying at least one printing material in a flowable state to the or each print head, and at least one pressure regulating device for regulating the back pressure of the or each flowable printing material to the or each print head. The supply system may include at least one supply path, and in this patent application, includes at least one pump containing a screw (or a pump containing a rotor).

[0006] Current 3D processes use liquid tempered chocolate to fill barrels, which are then cooled and stored to crystallize before use in a 3D printer. The present invention eliminates this process step by using a steady stream of room temperature solid (crystallized) chocolate as a direct feed to the 3D printer or to fill the 3D printing barrel.

[0007] It would therefore be advantageous to provide 3D printing apparatus and methods suitable for 3D printing chocolate and other confectionery products, wherein a continuous process is possible, which can be modified in situ, and wherein changes in material flow, volume and consistency can be accommodated without stopping or adversely affecting the 3D printing process.

[0008] It would also be advantageous to provide a 3D printing apparatus, particularly for confectionery and chocolate, wherein extrusion of chocolate can be performed with solid raw materials (such as chocolate flakes or powder), and extrusion of chocolate can be performed continuously regardless of changes in volume, flow rate or consistency of the chocolate material.

[0009] It is therefore an object of embodiments of the present invention to overcome or mitigate at least one of the problems of the prior art. Summary of the invention

[0010] According to a first aspect of the present invention, there is provided an apparatus for forming a steady flow of plasticized solid feed material, the apparatus comprising:

[0011] a. a piston punching portion in a cylinder, the piston punching portion in the cylinder is used to compact the crushed solid feed material to form a solid billet of feed material in the cylinder, and to extrude at least a portion of the solid billet from the outlet end of the cylinder;

[0012] b. a transfer path communicating with the outlet end of the cylinder;

[0013] c. A heater associated with a portion of at least a portion of the transfer path to plasticize and heat the feed material to a temperature to form a feed of plasticized solid feed material.

[0014] According to a second aspect of the present invention, there is provided a method for forming a stable flow of plasticized solid feed material, the method comprising the following steps:

[0015] a. introducing the crushed solid feed material into the piston stamping portion of the cylinder;

[0016] b. compacting the crushed feed material to form a solid billet of feed material in the cylinder;

[0017] c. extruding at least a portion of the solid billet from the outlet end of the cylinder into a transfer path communicating with the outlet end of the cylinder;

[0018] d. Heating the feed material in at least a portion of the transfer path to plasticize the feed material, and heating the feed material to a temperature to form a feed of plasticized solid feed material.

[0019] An apparatus and method for processing a granular solid material to form the plasticized solid feed material is provided, a solid billet is formed in a cylinder, and the solid billet material is then extruded into a conduit heated to a certain temperature to form a direct feed of plasticized solid feed (crystallized) chocolate for use with a 3D printer or loaded into a barrel used by a 3D printer. Crystallized chocolate is formed by tempering so that the cocoa butter in the chocolate is in a stable crystalline form. Properly crystallized chocolate has desirable texture characteristics, such as a good "crisp" feel and mouthfeel, a shiny appearance and resistance to melting. Products formed using under-crystallized chocolate have a grayish chocolate shell, dark spots, and melt on contact. In addition, molded chocolates and hollow shapes formed using under-crystallized chocolate will harden very slowly, be difficult to demould, and have a suboptimal appearance.

[0020] Although the invention may be described more specifically with reference to forming plasticised solid feed materials, particularly food materials such as chocolate, in a 3D printing or shaping process, the plasticised solid feed materials may be used in a wider range of shaping processes, depending on the type of material used, such as in extrusion to deposit "reshaped" chocolate or other feed material onto a shaped strip or mould, or to co-extrude it with, for example, a filler.

[0021] The or each feed material may comprise any material which is in a solid state, preferably a particulate solid state, at ambient temperature (eg room temperature) which may be heated to a plasticised but still solid state.

[0022] The or each feed material may comprise a polymeric material, an elastomeric material, a plastic material, a plastic material or a food material. In a preferred embodiment, the feed material is a food material, more preferably a confectionery material. In a particularly preferred embodiment, the confectionery material is chocolate, such as milk chocolate, dark chocolate, white chocolate or compound chocolate.

[0023] The apparatus preferably forms a steady stream of plasticized solid feed material exiting the transfer path.The piston-in-cylinder ram first forms a solid compressed billet in the cylinder and then plasticizes the material while conveying through the transfer path.

[0024] The definition of plasticized solid feed material is important. It is the form of plasticized solid feed material used in another downstream process (in contrast to "feed material", which is fed into the process to form plasticized solid feed material). The feed material entering the process / equipment will preferably be solid, and may be a granular solid. Importantly, the feed material leaving the process / equipment is solid, but softened or plasticized to allow forced flow through the transfer path. Preferably, the plasticized solid feed material will not flow once the driving force applied by the piston stamping portion in the cylinder is removed. The plasticized solid material in the piston stamping portion in the cylinder is not liquid, and preferably does not flow under the influence of gravity. In order to achieve this state of plasticized solid feed material, the temperature of the plasticized solid feed material should be kept below the melting temperature of the feed material. For example, for chocolate feed material (although depending on the composition of the chocolate), the temperature is typically between 23°C and 35°C, preferably about 29°C. It is preferred that the temperature of the feed material at the outlet of the transfer path is about 29°C as this will be preferred for the plasticized solid feed material. It is preferred that during the process the temperature of the plasticized solid feed material is always below 30°C. The chocolate is preferably not melted at any stage but is plasticized or softened or otherwise warmed so that it can be transported throughout the process and used in subsequent processes.

[0025] The apparatus includes a piston-in-cylinder ram for compacting comminuted feed material to form a solid billet of feed material in the cylinder and extruding at least a portion of the solid billet from an outlet end of the cylinder.

[0026] The crushed feed material can be fed into the piston stamping part in the cylinder. The crushed feed material can have a size between 1 mm and 5 mm. In the feed to the piston stamping part in the cylinder, there is usually a size distribution of the crushed feed material.

[0027] The feed material may be flakes, lumps, "buttons," granules, etc. The feed material may be provided in a larger size and broken up or otherwise reduced in size for feeding into the piston ram in the cylinder.

[0028] A cylinder filling hopper or similar device may be provided to collect the shredded feed material and direct the shredded feed material into the upper end of the cylinder piston stamp. In one form, the shredded feed material may be gravity fed into the upper end of the cylinder piston stamp. Agitation may be provided to assist in filling the cylinder piston stamp. The hopper and / or the cylinder piston stamp may be agitated to assist in filling.

[0029] The piston of the piston ram in the cylinder will preferably reciprocate. The piston will preferably move in a substantially vertical direction.

[0030] The piston-in-cylinder punch may be located at the lower end of the cylinder filling hopper. The piston of the piston-in-cylinder punch may extend through the outlet opening of the cylinder filling hopper. This may assist in pressing the shredded feed material into the upper end of the piston-in-cylinder punch.

[0031] The lower end of the piston will preferably clear the upper end of the outlet opening of the cylinder filling hopper at the top of the piston's upstroke. This can allow more comminuted feed material to enter the upper part of the cylinder, preferably assisted by gravity and / or stirring.

[0032] On the downward stroke of the piston, the shredded feed material is initially compacted at the upper portion of the cylinder. This initial compaction will preferably allow most of the air to escape the cylinder from around the piston. Then, further downward movement of the piston in the cylinder will preferably serve to compress the compacted shredded feed material to form a solid billet of feed material at the lower portion of the cylinder. The lower end of the cylinder is preferably converging, leading to an outlet of the cylinder, so as to assist in forming the billet in the lower portion of the cylinder. The billet is preferably a solid mass of compressed material.

[0033] The billet may always be present in the lower portion of the cylinder, that is, the piston never reaches the outlet end of the cylinder, so that a "billet" of material remains in the cylinder. Alternatively, the piston may squeeze out all of the billet before returning to the upstroke to refill. This alternative is less preferred because it may trap air in the cylinder and / or within the billet itself.

[0034] The cylinder is preferably relatively small in diameter to minimize the force required to compress the material into a blank. The preferred inner diameter of the cylinder is between 15 mm and 500 mm. For relatively small-scale embodiments, an inner diameter of about 20 mm is preferred.

[0035] An air gap may be provided between the outer cylindrical surface of the piston and the inner cylindrical surface of the cylinder. The air gap may allow air within the shredded feed material to escape during compaction and / or compression. The air gap may be about 0.1 mm. For example, the inner diameter of the cylinder may be 22.5 mm, and the outer diameter of the piston may be 22.3 mm.

[0036] The piston speed is preferably relatively slow on the downstroke. The speed of the downstroke may be lower than the speed of the upstroke. Downstroke speeds between 1 mm / s and 5 mm / s are preferred, with about 1.5 mm / s being particularly preferred.

[0037] The piston may have a flattened or shaped top end. A convex top end may be preferred.

[0038] The compaction and / or compression of the shredded feed material in the cylinder may increase the temperature of the material in the cylinder. As mentioned above, it is important that the temperature of the material remains relatively low. The temperature of the cylinder may be controlled to control the temperature of the material in the cylinder. Cooling may be provided. A cooling mechanism may be provided around the cylinder or a portion thereof, particularly around the lower portion where compression of the shredded feed material preferably occurs. Compression in the lower portion of the cylinder may at least begin to plasticize the feed material in the blank within the lower portion of the cylinder.

[0039] Cooling may be provided immediately after the outlet of the cylinder. Cooling may be provided immediately after the outlet of the cylinder relative to a portion of the transfer path. Preferably, cooling may be provided between the outlet of the cylinder and the heater. Any cooling method may be used, for example, a fan or a cooling jacket. Any cooling may preferably act circumferentially around a portion of the transfer path. In this case, a material temperature of about 15°C and 20°C may be preferred.

[0040] The length of the cylinder may be between 100 mm and 500 mm. For a benchtop example, the length of the cylinder may be between 100 mm and 150 mm, and most preferably about 125 mm. The length should be long enough to allow the shredded feed material to be initially compacted at the upper portion of the cylinder and then compressed into a billet at the lower portion of the cylinder. If the billet is too large in the cylinder, the force required to move it will increase, but it is also important that the billet is formed in the cylinder and a portion of the billet is retained at the lower portion of the cylinder to minimize air in the transfer path that is undesirable for a consistent product.

[0041] A cylinder having a height of about 125 mm allows a compaction height of about 60 mm to 65 mm and a compression height (blanket height) of about 60 mm to 65 mm. When the size of the cylinder is changed, the ratio of compaction height to compression height can remain similar or the same, about 1:1.

[0042] The apparatus also includes a transfer path that communicates with the outlet end of the cylinder. The transfer path may be an elongated conduit. The length of the transfer path is important because it should be long enough to allow heating of the blank (e.g., to allow the chocolate feed material to reach a plasticized state), but not too long because the length of the transfer path will increase friction in the transfer path, which in turn will require a greater force from the piston ram in the cylinder to drive the blank through the transfer path.

[0043] A piston-in-cylinder ram will also preferably be used to drive at least a portion of the blank through the transfer path.

[0044] A slower temperature rise in the blank is preferred over a faster temperature rise. A slower temperature rise in the blank is preferably more controllable. Therefore, the length of the transfer path is preferably optimized to heat the blank to the preferred temperature and then maintain the temperature of the blank at that temperature for the remaining length of the transfer path.

[0045] The transfer path may be a conduit of substantially circular cross-section. The conduit will preferably have a suitably small inner diameter to minimize any interface layer effects. This may allow the billet to be heated as it travels through the conduit and to be fully plasticized throughout the thickness of the billet.

[0046] The length of the conduit and the inner diameter of the conduit will be relevant parameters. For example, a conduit with an inner diameter between 2 mm and 10 mm is preferred, and more preferably an inner diameter of about 4 mm-5 mm. When the inner diameter is about 4 mm-5 mm, the length of the conduit will preferably be between 500 mm-1000 mm, more preferably between 700 mm-900 mm, and most preferably between 800 mm-830 mm. This can provide enough length to heat the blank in the conduit to plasticize the blank while allowing the use of a heater that keeps the material at a sufficiently low temperature so that the blank will not melt. When the conduit is larger, a similar ratio can be used.

[0047] The transfer path conduit can be rigid rather than flexible, as long as the blank can be moved through the conduit under the influence of force, but not liquid.

[0048] The conduit may be shaped. A serpentine or coiled configuration is preferred. This configuration may also produce axial and / or circumferential mixing of the billet in the conduit as the billet travels through the conduit, rather than piston flow. This may be used to mix the billet as it travels through the conduit, expose all portions of the billet to heat, and promote flow under force without melting.

[0049] The apparatus also includes a heater associated with a portion of the transfer path to plasticize and heat the feed material to a temperature to form a feed of plasticized solid feed material.

[0050] The heater may be provided over a majority of the length of the transfer path. Preferably, the heater is provided over at least half and preferably at least three quarters of the length of the transfer path.

[0051] Any type of heater may be used. One or more heaters may be provided. Different heaters may be provided in different parts of the length of the transfer path. Preferably, all sides of the transfer path conduit are heated equally.

[0052] The heater may be or include a sheath heater and / or a bath heater. In one embodiment, a bath heater may be provided over a portion of the length of the transfer path conduit and a sheath heater may be provided over another portion of the length of the transfer path conduit. The bath heater may be provided closer to the outlet end of the piston ram in the cylinder and the sheath heater is provided after the bath heater.

[0053] The temperature of the blank in the transfer path is important because an elevated temperature is preferably required to plasticize the blank to allow flow under force, but the temperature is preferably low enough to prevent melting. The temperature of the blank in the conduit will generally depend on a number of parameters, but will preferably be between 23° C. and 35° C., more preferably about 30° C., and most preferably between 28° C. and 32° C. For example, processing the blank at this temperature will preferably plasticize but not melt the chocolate blank.

[0054] The device can be used in combination with a 3D printing device comprising at least one print head.

[0055] The transfer path can provide plasticized solid feed material to at least one supply path for a 3D printing device. In some embodiments, there may be at least 2, 3, 4, 5, 6, 7, 8, 9 or at least 10 supply paths. In a preferred embodiment, a single supply path can be provided.

[0056] The or each printhead may include an additional piston-in-cylinder stamping portion. The provision of an additional piston-in-cylinder stamping portion associated with the or each printhead may assist in the consistent discharge of plasticized solid printing material. The or each printhead may include a nozzle at its distal end. The presence of the nozzle helps to control the thickness of the printing material and / or guide the flow of the printing material as it leaves the printhead.

[0057] In an embodiment, the plasticized solid feed material is continuously supplied to the or each print head and can be extruded from the or each print head at any desired rate by adjusting the feed at the feed end of the device. Therefore, if a separate feed device is provided, the rate of extrusion from each print head can be controlled individually.

[0058] The or each supply path may comprise a single print head, or may comprise at least 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45 or at least 50 print heads and / or no more than 2, 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, 25, 30, 35, 40, 45 or no more than 50 print heads.

[0059] At least one print head of the supply path may be arranged in at least one print module. In some embodiments, the or each supply path includes at least 1, 2, 3, 4, 5, 6, 7, 8, 9 or at least 10 print modules. The or each print module may include at least 1, 2, 3, 4, 5, 6, 7, 8, 9 or at least 10 print heads. In some embodiments, the or each print module includes between 3 and 7 print heads, such as 5 print heads.

[0060] The apparatus may be used to fill a refillable or refillable cartridge. The refillable or refillable cartridge may function in a manner similar to a syringe. The refillable or refillable cartridge may comprise an elongated hollow barrel, a discharge port at one end of the barrel, and a movable plunger within the barrel for moving toward the discharge port to discharge material from the barrel and away from the discharge port to allow filling of the barrel.

[0061] The cartridge may be made of any material, but for cartridges carrying food material it will preferably be made of metal, with food grade stainless steel or similar being preferred. The cartridge may be of any suitable volume, preferably at least 50ml.

[0062] The discharge port of the cartridge may have an attachment structure provided to allow the cartridge to be (releasably) attached to a 3D printer. Threads may be preferred. One or more structures, such as a base or similar structure, may be provided to allow the discharge port to be engaged using a tool.

[0063] The plunger may be made of any material, but for food materials, may be metal, and food grade stainless steel or similar material is preferred, or food grade plastic. One or more wiper seals may be provided between the plunger and the barrel. The outside or portion of the plunger may include one or more base portions, such as a base, to allow the printer to apply a force to the plunger to force the plunger to move, typically toward a discharge port to discharge the material.

[0064] When the cartridge is filled, it can be oriented vertically or horizontally. During filling, the top end of the cartridge can be uppermost or lowermost. During filling, the cartridge can be mounted from the top end. During filling, the cartridge can be attached relative to an indexing mechanism to allow loading of multiple cartridges to be filled. A turntable or linear indexing mechanism can be used.

[0065] One method of filling the cartridge is to fill from the top, forcing the plunger in the opposite direction as the cartridge is filled.

[0066] An additional piston-in-cylinder ram may be used to inject material exiting the transfer path conduit into the barrel.

[0067] The barrel may be heated during the filling process to keep the material in a plasticized form during filling. Although any type of heater may be used, a sheath heater may be preferred. In use, the sheath heater may extend around the barrel of the barrel during filling. The sheath heater may be split or provided in more than one part to allow the parts to be separated for loading and removing the barrel. The parts may be hinged relative to each other.

[0068] Preferably, a coupling will be provided between the outlet of the transfer path and the top end of the cartridge.A mating dry-disconnect coupling is preferred as this can minimise or prevent leakage or loss of material when the cartridge is disconnected.

[0069] During filling, a back pressure or counter pressure may be applied to the plunger of the cartridge to prevent air from accumulating in the cartridge. A back pressure between 1 bar and 5 bar is preferred, with a back pressure of about 2 bar being particularly preferred.

[0070] In one aspect of the invention, there is provided a method for filling a barrel with plasticized solid feed material, the barrel comprising an elongated hollow barrel, a discharge port at one end of the barrel and a hollow movable plunger located within the barrel, the hollow movable plunger being adapted to move toward the discharge port to discharge the material from the barrel and away from the discharge port to allow the barrel to be filled. The method comprises the following steps:

[0071] A plunger coupled to the barrel relative to the piston stamping portion in the cylinder;

[0072] forcing plasticized solid feed material through the top end to at least partially fill the barrel; and

[0073] During filling, back pressure is applied to the plunger of the cartridge to prevent air from accumulating in the cartridge. DETAILED DESCRIPTION

[0074] In order that the present invention may be more clearly understood, one or more embodiments of the present invention will now be described by way of example only with reference to the accompanying drawings, in which:

[0075] Figure 1 is a schematic diagram of an apparatus for feeding one embodiment of a 3D printer including a barrel for plasticizing a solid feed material.

[0076] Figure 2 is a schematic diagram of an apparatus according to an embodiment.

[0077] Figure 3 is an isometric view of one embodiment of an apparatus for forming a barrel and filling the barrel with plasticized solid feed material.

[0078] Figure 4 is a cross-sectional side view of a cartridge according to one embodiment.

[0079] Figure 5 is a schematic cross-sectional view of a plurality of cartridges in a partially filled configuration.

[0080] exist Figures 1 to 3 In the illustrated embodiment, an apparatus 10 for forming a steady flow of plasticized solid feed material is shown. The illustrated apparatus 10 includes a piston-in-cylinder ram 11 for compacting shredded feed material to form a solid billet 12 of feed material in a cylinder 13 and extruding at least a portion of the solid billet 12 from the outlet end of the cylinder 13. An elongated transfer path conduit 14 is provided in communication with the outlet end of the cylinder 13. A hot bath 15 is associated with at least a portion of the transfer path conduit 14 to plasticize and heat the feed material to a certain temperature to form a feed of plasticized solid feed material.

[0081] Figures 1 to 3 The illustrated apparatus forms a steady stream of plasticized solid confectionery material (chocolate, such as milk chocolate, dark chocolate, white chocolate or compound chocolate) as feed material, exiting the transfer path conduit 14. The piston-in-cylinder ram 11 first forms a solid compressed billet 12 in the cylinder 13, and then plasticizes the material while conveying through the transfer path conduit 14.

[0082] For chocolate feed material (although depending on the composition of the chocolate), the processing temperature of the billet in the transfer path conduit 14 is preferably about 29°C. It is preferred that the feed material temperature at the outlet of the transfer path conduit 14 is about 29°C, as this will be preferred for plasticizing the solid feed material. It is preferred that the temperature of the plasticized solid feed material is always below 30°C during the process. The chocolate is then not melted at any stage, but is plasticized or softened or otherwise warmed and thus plasticized.

[0083] The crushed solid feed material is fed into the in-cylinder piston stamping 11. The crushed feed material may have a size between 1 mm and 4 mm. In the feed to the in-cylinder piston stamping 11, there is usually a size distribution of the crushed feed material.

[0084] The feed material may be flakes, lumps, "buttons," granules, etc. The feed material may be provided in a larger size and broken up or otherwise reduced in size for feeding into the piston ram in the cylinder.

[0085] like Figure 1As illustrated, a shredder 18 driven by a motor 21 is provided above a collecting hopper 19, which shreds the feed material and supplies the shredded feed material to a laterally extending guide tray 20 extending above the cylinder filling hopper 17. The guide tray is associated with a mechanical agitator 22 to agitate the shredded feed material so that it moves along the guide tray and over the cylinder filling hopper 17.

[0086] exist Figure 1 and Figure 3 In the illustrated embodiment, the cylinder filling hopper 17 collects the crushed feed material and directs the crushed feed material into the upper end of the cylinder piston ram 11. In the illustrated embodiment, the crushed feed material is gravity fed into the upper end of the cylinder piston ram 11. An agitator 23 is associated with the cylinder filling hopper 17 to assist in the filling of the cylinder piston ram 11. Figure 3 In the embodiment of the present invention, the shredder 18 is fed from a feed hopper 50 .

[0087] The piston 16 of the piston ram 11 in the cylinder will reciprocate in use. The piston 16 of the illustrated embodiment reciprocates in a substantially vertical direction.

[0088] like Figure 1 As shown, the cylinder 13 is located at the lower end of the cylinder filling hopper 17. The piston 16 of the piston ram 11 in the cylinder extends through the lower outlet opening of the cylinder filling hopper 17.

[0089] like Figure 1 As shown, the lower end of the piston 16 clears the upper end of the outlet opening of the cylinder filling hopper 17 at the top of the upward stroke of the piston 16. This can allow the shredded feed material to enter the upper part of the cylinder 13, preferably assisted by gravity and / or agitation.

[0090] like Figure 2 As shown, during the downward stroke of the piston 16, the shredded feed material is initially compacted at the upper portion 23 of the cylinder 13. This initial compaction may allow most of the air to escape the cylinder 13 from around the piston 16. Then, further downward movement of the piston 16 in the cylinder 13 will preferably serve to compress the compacted shredded feed material to form a solid billet 12 of feed material at the lower portion 24 of the cylinder 13. The lower end of the cylinder 13 is preferably converging, leading to an outlet of the cylinder 13, so as to assist in forming the billet 12 in the lower portion of the cylinder 13. At this stage, the billet 12 is preferably a solid mass of compressed feed material.

[0091] The blank 12 may always reside within the lower portion 24 of the cylinder 13 , that is, the piston 16 never inserts far enough into the cylinder 13 to reach the outlet end of the cylinder 13 so that a “bill” of material remains in the cylinder 13 .

[0092] The cylinder 13 is preferably relatively small in diameter to minimize the force required to compress the material into the billet 12. As illustrated, the inner diameter of the cylinder is approximately 20 mm.

[0093] An air gap is provided between the outer cylindrical surface of the piston 16 and the inner cylindrical surface of the cylinder 13. The air gap allows air within the shredded feed material to escape during compaction and / or compression. The air gap may be about 0.1 mm. In the illustrated embodiment, the inner diameter of the cylinder is 22.5 mm, and the outer diameter of the piston is 22.3 mm.

[0094] The piston speed is preferably relatively slow on the downstroke. The speed of the downstroke may be lower than the speed of the upstroke. A downstroke speed of about 1.5 mm / s is particularly preferred.

[0095] The compaction and / or compression of the shredded feed material in the cylinder may increase the temperature of the material in the cylinder 13. As discussed above, it is important that the temperature of the material remain relatively low.

[0096] In the illustrated embodiment, cooling 25 is provided immediately after the outlet of the cylinder 13. Any cooling method may be used, for example, Figure 1 The fan 25 shown blowing air or Figure 3 A cooling jacket 26 is shown. Any cooling may preferably act circumferentially around a portion of the transfer path. Here, a material temperature of about 15°C to 20°C may be preferred.

[0097] The length of the cylinder 13 of the illustrated embodiment is about 125 mm. The length is long enough to allow the shredded feed material to be initially compacted at the upper portion 23 of the cylinder 13 and then compressed into the billet 12 at the lower portion 24 of the cylinder 13. If the billet 12 is too large in the cylinder 13, the force required to move it will increase, but it is also important that the billet 12 is formed in the cylinder 13 and a portion of the billet 12 is retained at the lower portion 24 of the cylinder 13 to minimize air in the transfer path conduit 14 that is undesirable for a consistent product.

[0098] Figure 2 The height of the cylinder 13 shown is about 125 mm, allowing a compaction height of about 60 mm to 65 mm and a compression height (blank height) of about 60 mm to 65 mm.

[0099] As shown, the transfer path is an elongated conduit 14. The length of the transfer path conduit 14 is important because it should be long enough to allow heating of the blank 12 (e.g., to allow the chocolate feed material chocolate to plasticize without de-tempering / de-crystallizing the material), but not too long because the length of the transfer path conduit 14 will increase the friction in the transfer path conduit 14, which in turn will require a greater force from the piston ram 11 in the cylinder to drive at least a portion of the blank 12 through the transfer path conduit 14.

[0100] The piston-in-cylinder ram 11 will be used to compress the feed material and also drive the blank 12 through the transfer path conduit 14 .

[0101] The blank 12 is heated in the transfer path conduit 14. A slower temperature rise in the blank 12 is preferred over a faster temperature rise. A slower temperature rise in the blank 12 is preferably more controllable. Therefore, the length of the transfer path conduit 14 is preferably optimized to heat the blank 12 to the preferred temperature and then maintain the temperature of the blank 12 at that temperature for the remaining length of the transfer path conduit 14.

[0102] The cross-section of the transfer path conduit 14 of the illustrated embodiment is substantially circular. The conduit 14 will preferably have a suitably small inner diameter to minimize any interface layer effects. This can allow the blank 12 to be heated and fully plasticized throughout the thickness of the blank 12 as it travels through the conduit.

[0103] The length of the conduit 14 and the inner diameter of the conduit 14 will be relevant parameters. The inner diameter of the exemplary conduit 14 is about 4mm-5mm. When the inner diameter is about 4mm-5mm, the length of the conduit 14 is preferably between 800mm-830mm. This can provide sufficient length to heat the billet 12 in the conduit to plasticize the billet 12, while allowing the use of a heater that keeps the material at a sufficiently low temperature so as not to melt the billet 12.

[0104] The illustrated transfer pathway catheter 14 is rigid.

[0105] like Figure 2 As shown, the conduit 14 has a serpentine or coiled configuration. This can be used to mix the billet 12 as it travels through the conduit 14, exposing all portions of the billet 12 to heat and promoting flow under force without melting.

[0106] like Figures 1 to 3 As shown in the embodiment of each figure, a heater is provided for at least half and preferably at least three quarters of the length of the transfer path. Preferably, all sides of the transfer path conduit 14 are heated equally.

[0107] Figure 1 The heater in is a sheath heater 25. Figure 2 and Figure 3 In the embodiment, a bath heater 15 is provided over a portion of the length of the transfer path conduit 14. Figure 3 In the embodiment shown, a sheath heater 28 is provided after the bath heater 15 over another portion of the length of the transfer path conduit 14 .

[0108] The temperature of the blank 12 in the transfer path conduit 14 is important because an elevated temperature is required to plasticize the blank 12 to allow flow under force, but the temperature should preferably remain low enough to prevent melting, de-tempering or over-softening. The temperature of the blank 12 in the conduit will typically depend on a number of parameters, but will preferably be between 29° C. and 30° C. For example, processing the blank 12 at this temperature will preferably plasticize but not melt the chocolate blank 12.

[0109] like Figure 1 As shown, the device 10 can be used in conjunction with a 3D printing device including at least one print head.

[0110] like Figure 1 As illustrated, a pair of cartridges 29 are provided relative to the printing platform. Each cartridge is associated with a supply path at a lower end that is connected to a cartridge discharge port leading to two print nozzles 30. Each print nozzle 30 has a print cylinder 31 associated therewith to help ensure consistent feeding of printing material from the cartridge to the print nozzle 30.

[0111] A single motor 32 is shown to move the plungers of both cartridges 29. A motor 33 is also provided to drive the two print cylinders of each platform.

[0112] An actuation valve 34 is provided for filling and priming the supply path between the cartridge discharge and the print nozzle 30. An actuation valve 35 is also provided at the print nozzle 30.

[0113] exist Figure 1 In the example, there is an XY plate adjuster 36 for each nozzle group's printing platform, and there is a Z plate adjuster 37 for each nozzle group's printing platform.

[0114] The apparatus may also be used to fill a refillable or refillable cartridge 29, an example of which is shown in Figure 4 The fillable or refillable cartridge 29 may function in a manner similar to a syringe. Figure 4 The illustrated fillable or refillable cartridge includes an elongated hollow barrel 38, a discharge port 39 at one end of the barrel 38, and a movable plunger 40 within the barrel 38 for moving toward the discharge port 39 to discharge material from the barrel 38 and away from the discharge port 39 to allow the barrel 38 to be filled.

[0115] The cartridge 38 may be made of any material, but for food materials, food grade stainless steel or similar material is preferred. The cartridge has a material volume 41 of approximately 300 ml.

[0116] The discharge port 39 of the cartridge may have an attachment structure, such as a threaded portion (not shown), provided to allow the cartridge 29 to be (releasably) attached to a 3D printer (an example of which is shown in FIG. Figure 1 example in).

[0117] One or more configurations may be provided, such as Figure 4 The base 42 shown in FIG. 1 is provided to allow the use of a tool (not shown) to engage the discharge port 39 for attachment and detachment from the loading system and the 3D printer.

[0118] The plunger 40 may be made of any material, but for food materials, food grade stainless steel or similar materials are preferred. One or more wiper seals 43 may be provided between the plunger 40 and the barrel 38. The plunger 40 may also include one or more base substrates 44 to allow a printer (such as Figure 1 The printer shown in FIG. 1 applies force to the plunger 40 to force the plunger 40 to move toward the discharge port 39 , thereby discharging the material from the barrel 29 .

[0119] like Figure 4 and Figure 5 As shown, the plunger 40 may be hollow with an opening at its front end. The cartridge 29 may be filled with material through the hollow plunger 40 .

[0120] like Figure 3 or Figure 5 As shown, when the cartridge 26 is filled, it can be oriented vertically. During filling, the top end of the cartridge 26 can be at the uppermost portion.

[0121] like Figure 3 As shown, during filling, the cartridge 26 can be suspended from the top. During filling, the cartridge 26 can be attached relative to the indexing mechanism to allow loading of multiple cartridges to be filled. Figure 3 The rotary indexing disc shown or Figure 5 The linear indexing mechanism shown uses a servo motor 47 to drive the turntable through indexing rotation.

[0122] like Figure 3 As shown, an additional piston-in-cylinder ram may be used to inject material exiting the transfer path conduit into the barrel 26. Figure 3 In the figure, the additional piston-in-cylinder ram is located within the sheath heater 28 and reciprocates as indicated by the large arrow.

[0123] like Figure 3As shown, the barrel 26 may be heated during the filling process to keep the material in a plasticized form during filling. Although any type of heater may be used, a sheath heater 45 may be preferred. Figure 3 As shown, in use, during filling, the sheath heater 45 may extend around the barrel 38 of the cartridge 26. The illustrated sheath heater 45 is split or provided in more than one part to allow the parts to be separated for loading and removing the cartridge 26. The parts may be hinged relative to each other.

[0124] Preferably, a mating dry-disconnect coupling 48 will be provided between the outlet of the transfer path conduit 14 and (the plunger 40 of) the cartridge 26 as this will minimize or prevent leakage or loss of material when the cartridge 26 is disconnected.

[0125] During filling, a back pressure or counter pressure 46 may be applied to the plunger 40 of the cartridge 26 to prevent air from accumulating in the cartridge 26, such as Figure 2 In the illustrated embodiment, a back pressure of about 2 bar is particularly preferred.

[0126] like Figure 3 As shown, a plunger driver 49 with a load cell is used to apply back pressure to the plunger during filling.

[0127] One or more embodiments have been described above by way of example only. Many modifications may be made without departing from the scope of protection defined in the appended claims.

Claims

1. An apparatus for forming a stable flow of plasticized solid feed material, the apparatus comprising: a. a piston punching portion in a cylinder, the piston punching portion in the cylinder being used to compact the crushed solid feed material to form a solid billet of feed material in the cylinder, and to extrude at least a portion of the solid billet from the outlet end of the cylinder; b. a transfer path, wherein the transfer path is connected to the outlet end of the cylinder; c. A heater associated with at least a portion of the transfer path to plasticize and heat the solid feed material to a temperature to form a feed of plasticized solid feed material.

2. Apparatus according to claim 1, wherein the feed material is a food material, optionally a confectionery material selected from the group comprising chocolate, milk chocolate, dark chocolate, white chocolate or compound chocolate.

3. The apparatus according to claim 1 or claim 2, further comprising a cylinder filling hopper provided to collect crushed solid feed material and direct the crushed solid feed material into the upper end of the piston ram in the cylinder.

4. Apparatus according to any one of the preceding claims, wherein the piston of the piston ram in the cylinder reciprocates and the lower end of the piston clears the upper end of the outlet opening of the cylinder at the top of the piston's upstroke.

5. Apparatus according to any one of the preceding claims, wherein an air gap is provided between an outer cylindrical surface of the piston and an inner cylindrical surface of the cylinder.

6. Apparatus according to any one of the preceding claims, further comprising cooling mechanism provided immediately after the outlet of the cylinder with respect to a portion of the transfer path immediately after the outlet of the cylinder.

7. The apparatus of any preceding claim, wherein the transfer pathway conduit is flexible.

8. Apparatus according to any one of the preceding claims, wherein the transfer pathway conduit has a serpentine or coiled configuration.

9. Apparatus according to any of the preceding claims, wherein the heater is provided with respect to at least half and preferably at least three quarters of the length of the transfer path.

10. Apparatus according to any preceding claim, wherein a first heater is provided over a portion of the length of the transfer path conduit.

11. Apparatus according to any one of claims 10, wherein a second heater is provided after the first heater over another part of the length of the transfer path conduit.

12. Apparatus according to any one of the preceding claims, further comprising a filling station having at least one fillable or refillable cartridge relative to the outlet end of the transfer path conduit.

13. Apparatus according to any one of claims 12, wherein the fillable or refillable cartridge comprises an elongated hollow barrel, a discharge port at one end of the barrel and a movable plunger within the barrel for moving towards the discharge port to discharge material from the barrel and away from the discharge port to allow the barrel to be filled with the plasticised solid feed material.

14. Apparatus according to claim 13, wherein the discharge port of the fillable or refillable cartridge has an attachment structure provided to allow the fillable or refillable cartridge to be releasably attached to a downstream process.

15. Apparatus according to any one of claims 12 or 13, wherein a plunger is hollow with an opening at its front end such that the fillable or refillable cartridge is filled with the plasticised solid feed material through the plunger.

16. Apparatus according to any one of claims 12 to 15, wherein the plasticised solid feed material exiting the transfer path conduit is injected into the fillable or refillable cartridge using an additional piston-in-cylinder ram.

17. Apparatus according to any one of claims 12 to 16, further comprising a heater for heating the fillable or refillable cartridge during filling.

18. Apparatus according to claim 17, wherein the heater is provided in more than one section to allow the more than one section to be separated for loading and removing the cartridge.

19. The apparatus of any one of claims 12 to 17, further comprising a mating dry disconnect coupling provided with respect to the fillable or refillable cartridge.

20. A 3D printing device, comprising a device for forming a stable flow of plasticized solid printing material according to any one of the preceding claims and at least one print head, wherein the plasticized solid printing material is provided to at least one supply path of the 3D printing device.

21. A method for forming a steady flow of plasticized solid feed material, the method comprising the steps of: a. introducing the crushed solid feed material into the piston stamping portion of the cylinder; b. compacting the crushed solid feed material to form a solid billet of feed material in the cylinder; c. extruding at least a portion of the solid billet from the outlet end of the cylinder into a transfer path communicating with the outlet end of the cylinder; d. Heating the feed material in at least a portion of the transfer path to plasticize the feed material, and heating the feed material to a temperature to form a feed of plasticized solid feed material.

22. The method of claim 21, wherein the extruding step forces the plasticized solid feed material to flow through the transfer path.

23. A method according to claim 21 or claim 22, wherein the temperature of the plasticised solid feed material is maintained below the melting temperature of the feed material.

24. The method of claim 23, wherein for chocolate feed material, the temperature of the plasticised solid feed material is heated to between 23°C and 35°C by a heater.

25. A method according to any one of claims 21 to 24, further comprising the step of reducing the solid feed material to a size between 1 mm and 5 mm prior to introduction into the in-cylinder piston stamping.

26. A method according to any one of claims 21 to 25, wherein on a downward stroke of the piston the reduced solid feed material is initially compacted at an upper part of the cylinder.

27. The method of claim 26, wherein further downward movement of the piston in the cylinder compresses the compacted, shredded solid material to form a solid billet of feed material at a lower portion of the cylinder.

28. A method according to any one of claims 21 to 27, wherein the blank is always present in the lower part of the cylinder.

29. The method of any one of claims 21 to 28, wherein the billet of plasticized solid feed material undergoes axial and / or circumferential mixing in the transfer path conduit as the billet of plasticized solid feed material travels through the transfer path conduit.

30. The method of any one of claims 21 to 29, wherein the billet in the transfer path conduit is maintained between 23°C and 35°C.

31. A method according to any one of claims 21 to 30, comprising the further step of filling at least one fillable or refillable cartridge, the at least one fillable or refillable cartridge comprising an elongated hollow cylinder, a discharge port at one end of the cylinder and a movable plunger located within the cylinder, the movable plunger being adapted to move towards the discharge port to discharge material from the cylinder and away from the discharge port to fill the cylinder with the plasticized solid feed material.

32. A method according to claim 31 , wherein the plunger is hollow and the method comprises the step of filling at least one fillable or refillable cartridge through the hollow plunger.

33. A method according to any one of claims 31 or 32, comprising the further step of applying back pressure to the plunger during filling to prevent accumulation of air in the cartridge.

Images