Device for suspending particles in a fluid polymer and related apparatus and process

Abstract

A device (10) for suspending particles in a fluid polymer (30) for use in a stereolithographic printing system (26) comprises an ultrasound emitter (12) configured to emit ultrasounds towards a tank (28) of the stereolithographic printing system (26) so as to keep the particles in suspension in the fluid polymer (30) and to heat the fluid polymer (30), and further comprises a temperature sensor (14) configured to measure the temperature of the fluid polymer (30) for use in the stereolithographic printing system (26) and to generate a signal representative of such measurement.

Description

[0001] Device for suspending particles in a fluid polymer and related apparatus and process

[0002] Technical Field

[0003] The present invention is in the field of three-dimensional printing. In particular, the invention relates to a device for suspending particles in a fluid polymer, to an apparatus for rapid prototyping comprising and using said device for suspending particles, and to a method for printing fluid polymer material.

[0004] State of the art

[0005] To date, rapid prototyping systems are known, that is, systems that, starting from a mathematical drawing or model of an object, are able to physically realize the object, in a relatively short time, by means of a three-dimensional printing system or additive manufacturing.

[0006] Among the most known and used techniques of rapid prototyping is stereolithography, that is, a technique that, starting from mathematical models, creates physical objects using a three- dimensional printer and material that is photosensitive when exposed to light.

[0007] Typically, the stereolithographic printing process involves preparing a tank of photosensitive material and selectively irradiating the material contained therein with a light source, for example ultraviolet, in such a way as to cause its polymerization, i.e. photopolymerization, and, therefore, curing, i.e. selective solidification according to a predetermined model.

[0008] A plate may be immersed in the photosensitive material, such that a layer of material covers the plate and is irradiated with the light source, polymerizing. The plate is then progressively immersed (or lifted) into the tank to allow an additional layer of photosensitive material to cover the newly polymerized layer. By irradiating the fluid material again, selectively, a second layer of polymerized material is obtained. The method continues until the physical object consistent with the predetermined model is obtained.

[0009] To date, different stereolithography techniques are known. Examples of known stereolithographic techniques are laser stereolithography which uses an ultraviolet laser beam as a light source to irradiate the photosensitive material, DLP (Digital Light Processing) stereolithography which uses a light projector as a light source by irradiating the entire layer of photosensitive material, and LCD stereolithography which uses LCD (Liquid Crystal Display) screens as a light source, selectively backlit by a light source.

[0010] The material used in stereolithographic printing is generally a photosensitive material such as a resin, i.e., a polymer material, which is polymerized or photopolymerized by a light source to obtain hardening or solidification thereof. It is possible to add a second material in the resin, in the form of fibres or powders, for example of carbon, ceramic or glass to vary the mechanical and / or thermal properties thereof, and thus also vary the properties of the physical object made.

[0011] During the printing process, the resin remains in the tank for a rather long time, during which the material added and / or dispersed in the resin tends to deposit, altering the characteristics and uniformity of the resin and, therefore, of the object made by the printer.

[0012] Three-dimensional printing systems capable of holding the particles of added material in suspension in the resin using blowers are known in the art, but leave residues of air in the resin itself.

[0013] The temperature of the resin can also be varied while it is in the tank. An excessive lowering of the temperature leads to the resin hardening early, while excessive heating leads to the resin being altered due to the solvents contained therein. From the point of view of the scientific and patent literature, some proposals are known that address this technical problem without fully solving it and are described in the following documents :

[0014] - Scientific publications HECTOR SANDOVAL J. ET AL: "Functionalizing stereolithography resins: effects of dispersed multi-walled carbon nanotubes on physical properties", RAPID PROTOTYPING JOURNAL, vol. 12, no. 5, 1 October 2006 (2006-10-01) , pages 292-303, XP093081491, GB ISSN: 1355-2546, 001: 10.1108 / 13552540610707059;

[0015] - The patent US 6 283 997 81 (GARG RAJEEV [US] ET AL) 4 September 2001 (2001-09-04) .

[0016] Summary disclosure of the invention

[0017] The present patent intends to overcome the above critical issues by implementing a device for suspending particles in a fluid polymer, a rapid prototyping apparatus that exploits said device and its method of use.

[0018] It is an object of the present invention to provide a device capable of improving the printing process.

[0019] It is a further object of the present invention to provide a device capable of improving the mechanical characteristics of a fluid polymer.

[0020] These and other objects are fully achieved according to the present invention by means of a device as defined in the appended Claim 1, an apparatus as defined in the appended Claim 6 and a method as defined in the appended Claim 9. Advantageous embodiments of the invention are specified in the dependent claims, the content of which is to be understood as an integral part of the description.

[0021] In summary, a device for suspending particles in a fluid polymer for use in a stereolithographic printing system comprises an ultrasound emitter configured to emit ultrasounds towards a tank of the stereolithographic printing system adapted to keep the particles in suspension in the fluid polymer and to heat the fluid polymer, and further comprises a temperature sensor configured to measure the temperature of a fluid polymer for use in the stereolithographic printing system and to generate a signal representative of such measurement .

[0022] Also part of the invention is a rapid prototyping apparatus comprising a device according to the first aspect of the invention and a stereolithographic printing system comprising a tank arranged to contain a fluid polymer with particles in suspension, a mobile printing platform, a forkli ft truck arranged to move the printing platform, and a source group arranged to emit light radiation .

[0023] Finally, the invention comprises a method for printing fluid polymeric material using a rapid prototyping apparatus , comprising the steps of : a ) preparing an apparatus according to the second aspect of the invention; b ) adj usting a position of the printing platform with respect to the tank by means of the forkli ft such that one face of the printing platform is at least partially immersed in the fluid polymer ; c ) driving the ultrasound emitter of the device in such a way that it emits ultrasounds towards the tank adapted to keep the particles in suspension in the fluid polymer and to heat the fluid polymer ; d) driving the source group in such a way as to polymeri ze the layer of fluid polymer adj acent to the face of the printing platform obtaining a layer of polymeri zed polymer ; e ) adj usting the position of the printing platform with respect to the tank by means of the forkli ft such that a layer of fluid polymer is arranged on the layer of polymeri zed polymer .

[0024] Brief description of the accompanying drawings

[0025] Further characteristics and advantages of the proposed technical solution will appear more evident in the following description of a preferred but not exclusive embodiment shown by way of example and not limitation in the accompanying three drawing plates , in which :

[0026] - Fig . 1 shows in a side view the device for suspending particles and a stereolithographic printing system;

[0027] - Fig . 2 shows in a side view the device for suspending particles of Fig . 1 coupled to the stereolithographic printing system .

[0028] It should be noted that the figures attached to the present patent application illustrate only one possible embodiment of the system, in order to better understand the advantages and features of the patent described .

[0029] These embodiments are therefore to be understood as purely illustrative and supportive of the present description without limitation of the inventive concept and above all of the scope of protection as defined in the appended claims .

[0030] Optimal method for implementing the invention

[0031] With reference to the attached f igures and with reference to Figure 1 , a device 10 for suspending particles in a fluid polymer 30 ; said fluid being used in a l ithographic printing system 26 . Said device 10 comprising an ultrasound emitter 12 configured to emit ultrasounds towards a tank 28 of said stereolithographic printing system 26 . Such ultrasounds are adapted to keep the particles in suspension in the fluid polymer 30 and thereby to heat the fluid polymer 30 . The device 10 also comprises a temperature sensor 14 configured to measure the temperature of the fluid polymer 30 for use in the stereolithographic printing system 26 and to generate a signal representative of the measurement .

[0032] The ultrasound emitter 12 may comprise one or more ultrasound transducers , i . e . devices capable of converting an electrical pulse into a mechanical pulse , for emitting mechanical vibrations and for transmitting these generated vibrations towards the tank 28 of the stereolithographic printing system 26 , and therefore towards the fluid polymer 30 contained therein and in particular towards the particles in suspension in the fluid polymer 30 .

[0033] Preferably, the temperature sensor 14 may be a non-contact temperature sensor, i . e . a temperature sensor capable of detecting the temperature of the fluid polymer 30 contained in the tank 28 without coming into contact with the polymer itsel f . Even more preferably, the temperature sensor 14 may comprise an infrared thermometer or an infrared thermal imaging camera .

[0034] In an alternative embodiment not illustrated in the figures , the temperature sensor 14 may comprise a contact temperature sensor, i . e . a temperature sensor 14 capable of detecting the temperature of the fluid polymer 30 contained in the tank 28 of the stereolithographic printing system 26 coming into contact with the polymer itsel f . Even more preferably, the contact temperature sensor 14 can comprise a plurality of thermocouples that can be arranged within the tank 28 , in contact with the fluid polymer 30 , in such a way as to measure the temperature in a plurality of points and obtain information on its distribution .

[0035] In an embodiment of the device 10 , the ultrasound emitter 12 may be arranged in the lower part of the device 10 and the temperature sensor 14 may be arranged in the upper part of the device 10 , both facing the tank 28 containing fluid polymer 30 in such a way as to respectively transmit the mechanical vibrations to the fluid polymer 30 and acquire information about the temperature of the fluid polymer 30 contained in the tank; preferably in such a way as to acquire information about the surface temperature of the fluid polymer 30 .

[0036] The device 10 may comprise an electronic control unit configured to control the device 10 and further configured to receive , process and / or store at least one signal representative of the measurement of the temperature sensor 14 . More particularly, the electronic control unit may comprise a user interface for programming the ultrasound emitter 12. Preferably, the user interface may comprise one or more buttons 16 for setting a driving program and / or one or more operating parameters of the ultrasound emitter 12, and may also comprise a display 18 for displaying information relating to the one or more driving programs and / or one or more settable operating parameters .

[0037] The driving programs may comprise at least one manual driving program, i.e., a driving program in which the user may manually set at least one or more emitter operating parameters, and an automatic driving program, i.e., a driving program that takes information relating to at least one or more emitter operating parameters from a storage medium, e.g., a storage medium associated with the device 10 and / or the stereolithographic printing system 26.

[0038] The operating parameters of the emitter may comprise a deposition time, i.e. a time duration within which the particles dispersed in the fluid polymer 30 deposit on the bottom of the tank 28, and a target temperature, i.e. a target temperature of the fluid polymer, i.e. a temperature at which the polymer remains fluid, without hardening, i.e. solidifying .

[0039] The control unit may also comprise a storage medium for storing at least one driving program of the ultrasound emitter 12 and / or at least one signal representative of the measurement of the temperature sensor 14.

[0040] In one embodiment, the storage medium may be external and connectable to the device 10 by a connection means 20 arranged on the device 10. In such an embodiment, the connection means 20 may comprise, for example, a memory card reader (SD card) or a USB connector. The external storage medium may be arranged to store at least one driving program of the ultrasound emitter 12 and / or one or more operating parameters of the ultrasound emitter 12 and / or at least one signal representative of the measurement of the temperature sensor 14 .

[0041] In an alternative embodiment , the storage medium may be integrated into the device 10 , i . e . may be internal to the device 10 , and may store at least one driving program and / or one or more operating parameters of the ultrasound emitter 12 and / or may store at least one signal representative of the measurement of the temperature sensor 14 .

[0042] The device 10 may also comprise a camera 22 for monitoring particles in the fluid polymer 30 .

[0043] Preferably, the camera 22 can be configured to monitor the presence of the particles in the fluid polymer 30 and their distribution in such a way as to provide such information to the electronic control unit for a control of the device 10 . The camera 22 can be disposed in an upper part of the device 10 and can be facing the tank 28 of the stereolithographic printing system 26 such that it can monitor the fluid polymer 30 and the dispersed particles .

[0044] The device 10 may comprise a plurality of ultrasound emitters 12 connected together and each configured to emit ultrasound towards the tank 28 of the stereolithographic printing system 26 . Preferably the emitters of the plurality of ultrasound emitters 12 may be electrically connected to each other and each ultrasound emitter 12 may be configured to be controlled by the electronic control unit .

[0045] The plurality of ultrasound emitters 12 may be electrically connected by electrical connection means 48 .

[0046] Advantageously, the use of multiple ultrasound emitters 12 may make it possible to emit and transmit the generated mechanical vibrations towards a larger volume of fluid polymer 30 contained in the tank 28 of the stereolithographic printing system 26 , thus making it possible to obtain a more homogeneous and uni form distribution of the particles within the entire volume of fluid polymer 30 . With reference to the accompanying drawings and in particular to Fig. 2, the second aspect claimed in the present invention is illustrated, namely an apparatus 24 for rapid prototyping, comprising the device 10 according to any of the embodiments described above and a stereolithographic printing system 26. The system for stereolithographic printing 26 comprises a tank 28 fixed and arranged to contain a fluid polymer 30 with particles in suspension.

[0047] The fluid polymer 30 used by the stereolithographic printing system 26 may be a photopolymerizable resin, i.e., a resin, e.g., epoxy resin, that polymerizes, i.e., photopolymerizes, and then cures, i.e., solidifies by means of a light, e.g., ultraviolet light, i.e., visible light.

[0048] Particles, which may also be referred to as "fillers", may be added to the fluid polymer material 30. Some examples of particles which may be added are carbon, ceramic or glass, and may be added, for example, in the form of fibres and / or powders. As is apparent to the person skilled in the art, other materials may be used as particles dispersed in the fluid polymer 30.

[0049] The particles may be added to the fluid polymer 30 in a predetermined amount, for example the fluid polymer material may be loaded from 10% to 90% by weight. The percentage of particles added to the fluid polymer 30 depends on the mechanical characteristics, e.g., mechanical strength, resilience, hardness, and / or structural characteristics desired for the object that can be obtained by the stereolithographic printing system.

[0050] The stereolithographic printing system 26 further comprises a movable printing platform 32, a forklift 36 arranged to move the printing platform 32 vertically, i.e. perpendicularly to the printing platform 32, with respect to the tank 28 and a source group 38 arranged to emit light radiation.

[0051] The stereolithographic printing system 26 may be any type of stereolithographic printing system known in the art for selectively polymerizing, i.e., photopolymerizing, the fluid polymer 30. In particular, the stereolithographic printing system 26 may be a laser stereolithography system, i.e. a system using an ultraviolet laser beam as the source group 38, a DLP (Digital Light Processing) stereolithography system using a light projector as the source group 38, or an LCD stereolithography system using LCD (Liquid Crystal Display) screens backlit by a light source as the source group 38.

[0052] In the embodiment illustrated in the figures, the source group 38 comprises a laser emitter 40 arranged to emit a laser beam, for example ultraviolet, and a lens group 42 that is movable and arranged above the tank 28 to direct the laser beam emitted by the laser emitter 40 towards the printing platform 32 and to polymerize, i.e. to selectively photopolymerize the fluid polymer 30.

[0053] Both stereolithographic printing approaches, known as top down and bottom up, may be used by the stereolithographic printing system 26 of the apparatus 24. The top down approach may provide that the system 26 has the source group 38 arranged above the tank 28 and that the printing platform 32 is lowered during printing. Differently, the bottom up approach may provide that the system 26 has a source group 38 arranged below the tank 28 and that the printing platform 32 is lifted during printing .

[0054] In the embodiment illustrated in the figures, the stereolithographic printing system 26 is configured to adopt a top-down printing approach, i.e. it is configured with the source group 38 arranged above the tank 28. Clearly, in an equivalent but not illustrated embodiment, the stereolithographic printing system 26 is configured to adopt a bottom-up printing approach, as just described.

[0055] In the embodiment illustrated in the figures, the device 10 for suspending particles in a fluid polymer 30 may be removably and replaceably coupled to the stereolithographic printing system 26. In such an embodiment , the stereolithographic printing system 26 may comprise an electronic control unit di f ferent from the control unit of the device 10 , and configured to control the source group 38 in such a way as to direct the laser beam emitted by the laser emitter 40 towards the printing platform 32 , at least partially immersed in the fluid polymer 30 .

[0056] In an alternative and non-illustrated embodiment , the device 10 for suspending particles in a fluid polymer 30 may be reali zed as a single body with the stereolithographic printing system 26 . In such an embodiment the device control unit 10 may be configured to also control the source group 38 so as to direct the laser beam towards the printing platform 32 .

[0057] A motor 46 may be comprised in the apparatus 24 for driving the forkli ft 36 such that the printing platform 32 moves vertically, i . e . perpendicularly to the printing platform 32 , with respect to the tank 28 .

[0058] In the preferred embodiment , the motor 46 can be an electric motor, but as is apparent to the person skilled in the art , nothing prevents the motor from being di f ferent , for example , a hydraulic motor .

[0059] A third aspect of the invention relates to a method for printing fluid polymeric material 30 by means of the rapid prototyping apparatus 24 comprising preparing the apparatus 24 according to the second aspect of the present invention .

[0060] The preparation of the apparatus may also comprise the definition of the driving program and / or the operating parameters of the emitter 12 , including the deposition time and the target temperature of the fluid polymer 30 .

[0061] The method further comprises adj usting a position of the printing platform 32 with respect to the tank 28 by means of the forkli ft 36 such that a face 34 of the printing platform 32 is at least partially immersed in the fluid polymer 30 .

[0062] In the embodiment illustrated in the figures , i . e . , stereolithographic printing with a top-down approach, the upper face 34 of the printing platform 32 may be at least partially immersed in the fluid polymer 30.

[0063] In an alternative and not illustrated embodiment, i.e. stereolithographic printing with a bottom up approach, the lower face 34 of the printing platform 32 can be at least partially immersed in the fluid polymer 30.

[0064] The method also comprises driving the ultrasound emitter 12 of the device 10 in such a way that it emits ultrasounds towards the tank 28, to keep the particles in suspension in the fluid polymer 30 and to heat the fluid polymer 30.

[0065] In one embodiment, the apparatus 24 may be configured such that the particles in the fluid polymer 30, contained within the tank 28, are suspended with a uniform distribution, i.e. with a homogeneous distribution within the tank 28.

[0066] Driving the ultrasound emitter 12 in such a way that it emits ultrasounds towards the tank 28, having set the deposition time and the target temperature of the fluid polymer, advantageously makes it possible to keep the particles present in the fluid polymer 30 in suspension, preventing deposition, and also makes it possible to heat the fluid polymer 30 to a target temperature to keep it liquid, preventing it from solidifying or hardening.

[0067] Keeping the particles in suspension in the fluid polymer 30, preventing deposition, and keeping the fluid polymer at the target temperature, preventing it from hardening, advantageously makes it possible to improve the mechanical characteristics of the fluid polymer and, therefore, the mechanical characteristics of the object obtained from the printing .

[0068] The method involves driving the source group 38 in such a way as to polymerize, i.e., photopolymerize, the layer of fluid polymer adjacent to the face 34 of the printing platform 32 obtaining a layer of polymerized polymer 44, i.e., photopolymerized, and then make it harden, i.e., solidify. Preferably, the layer of fluid polymer adjacent to the face 34 of the printing platform 32 may be selectively polymerized, i.e. at least some of the fluid polymer 30 adjacent to the face 34 is polymerized or photopolymerized.

[0069] In one embodiment, the source group 38 polymerizes, i.e., photopolymerizes, the fluid polymer on the upper surface 34 of the printing platform 38 such that it hardens or solidifies. The method therefore provides for adjusting the position of the printing platform 32 with respect to the tank 28 by means of the forklift 36 such that a layer of fluid polymer 30 is arranged on the layer of polymerized polymer 44, i.e. photopolymerized .

[0070] In the embodiment illustrated in the figures, i.e., printing with top down approach, the forklift 36 may be lowered such that a layer of fluid polymer 30 is disposed above the polymerized polymer layer 44.

[0071] Preferably, the steps of driving the ultrasound emitter 12, driving the source group 38, and adjusting the position of the printing platform 32 with respect to the tank 28 may be repeated sequentially one or more times.

[0072] Advantageously, the repetition of the driving of the ultrasound emitter 12 makes it possible to keep in suspension the particles present in the fluid polymer 30 preventing them from depositing on the bottom of the tank and also makes it possible to heat the fluid polymer 30 to a target temperature, improving the printing process overall.

[0073] Industrial applicability

[0074] The present invention can be advantageously used in the field of three-dimensional printing. While specific embodiments of the invention have been described, it is to be understood that this disclosure has been provided by way of illustration only and that the invention is in no way to be limited thereby. Various changes will be apparent to those skilled in the art in light of the foregoing examples . The scope of the invention is limited only by the appended claims .

Claims

Apparatus (24) for rapid prototyping comprising : a stereolithographic printing system (26) comprising: a fixed tank (28) adapted to contain a fluid polymer (30) with particles in suspension, a forklift (36) and a movable printing platform (32) , wherein the forklift (36) is arranged to move the printing platform (32) vertically with respect to the tank (28) , a source group (38) arranged to emit light radiation; characterized in that it further comprises: a device (10) for suspending particles, comprising: an ultrasound emitter (12) adapted to emit ultrasound towards the tank (28) of the stereolithographic printing system (26) to keep the particles in suspension in the fluid polymer (30) and heat the fluid polymer (30) , and a temperature sensor (14) adapted to measure the temperature of the fluid polymer (30) and to generate a signal representative of such measurement.

2. Apparatus (24) according to claim 1, wherein the device(10) comprises an electronic control unit for controlling the device (10) and configured to receive, process and / or store at least one signal representative of the measurement of the temperature sensor (14) .

3. Apparatus (24) according to claim 2, wherein the electronic control unit comprises a user interface for programming theultrasound emitter (12) , and a storage medium for storing at least one driving program of the ultrasound emitter (12) and / or at least one signal representative of the measurement of the temperature sensor (14) .

4. Apparatus (24) according to any one of the preceding claims, comprising at least one video camera (22) adapted to monitor particles in the fluid polymer (30) .

5. Apparatus (24) according to any one of the preceding claims, comprising a plurality of ultrasound emitters (12) connected to each other and each adapted to emit ultrasounds towards the tank (28) , preferably electrically connected to each other and configured to be controlled by the electronic control unit.

6. Apparatus (24) according to any one of the preceding claims, wherein the device (10) for suspending particles in the fluid polymer (30) is removably couplable and replaceable with the stereolithographic printing system (26) .

7. Apparatus (24) according to any one of the preceding claims, comprising a motor (46) , preferably electric, arranged for driving the forklift (36) such that the printing platform (32) moves vertically with respect to the tank (28) .

8. Method for printing fluid polymeric material (30) using a rapid prototyping apparatus (24) according to any of claims 1 to 7, comprising the steps of: a) preparing an apparatus (24) according to any of claims 1 to 7; b) adjusting a position ofthe printing platform (32) with respect to the tank (28) by means of the forklift (36) such that one face (34) of the printing platform (32) is at least partially immersed in the fluid polymer (30) ; c) driving the ultrasound emitter (12) of the device (10) in such a way that it emits ultrasounds towards the tank (28) , to keep the particles in suspension in the fluid polymer (30) and to heat the fluid polymer ( 30 ) ; d) driving the source group (38) in such a way as to polymerize a layer of fluid polymer (30) adjacent to the face (34) of the printing platform (32) obtaining a layer of polymerized polymer (44) ; e) adjusting the position of the printing platform (32) with respect to the tank (28) by means of the forklift (36) such that a layer of fluid polymer (30) is arranged on the polymerized polymer layer (44) .

9. Method for printing fluid polymeric material (30) by means of an apparatus (24) for rapid prototyping according to claim8, wherein steps c) , d) , e) are repeated in sequence one or more times.[0001][0002]STATEMENT UNDER ARTICLE 19 (1 )[0003]EXPLANATION OF AMENDMENTS AND THEIR IMPACT[0004]The amendments submitted herewith restructure the claims to focus on the inventive concept of an integrated apparatus for stereolithographic printing with real-time particle suspension capability.[0005]SUMMARY OF CHANGES[0006]The original independent claim 1 , which defined a standalone device for suspending particles, has been cancelled. The new independent claim 1 now defines a complete apparatus for rapid prototyping that integrates both the stereolithographic printing system and the particle suspension device as a unified system. This restructuring addresses clarity concerns while maintaining comprehensive protection for the inventive concept.[0007]The dependent claims 2-7 preserve all the advantageous features originally described in claims 2-5 and 7-8, now properly structured as dependent features of the integrated apparatus. The method claims 8-9 have been correspondingly updated to reflect the use of the integrated apparatus.[0008]TECHNICAL SIGNIFICANCE[0009]The amended claims define an apparatus that solves the technical problem of particle sedimentation during stereolithographic printing through continuous in-situ ultrasonic agitation and temperature control. Unlike prior art approaches that treat the resin before printing, the claimed invention maintains particle suspension throughout the entire printing process by integrating the suspension device directly within the printing apparatus.[0010]The ultrasound emitter operates continuously during printing to prevent particle settling while simultaneously providing controlled heating of the polymer. The temperature sensor enables real- time monitoring and control, ensuring optimal printing conditions. This integrated approach represents a significant advancement over conventional methods that rely on pre-treatment of the resin.[0011]INVENTIVE CONTRIBUTION[0012]The invention addresses the long-standing problem in stereolithographic printing of maintaining homogeneous particle distribution in filled resins during extended printing operations. The integration of ultrasonic suspension technology directly into the printing apparatus, rather than as a separate pre-processing step, provides continuous particle agitation synchronized with the printing process.[0013]The apparatus enables the production of composite objects with uniform particle distribution throughout their structure, which was previously difficult to achieve with conventional stereolithographic systems. The real-time temperature monitoring and control further enhance the printing process by maintaining optimal viscosity and curing conditions.[0014]IMPACT ON DESCRIPTION AND DRAWINGS[0015]The amendments do not require changes to the description or drawings, as all claimed features are fully supported by the original disclosure. The description adequately explains the integrated apparatus concept, the ultrasonic suspension mechanism, and the temperature control system. The drawings clearly illustrate the structural relationship between the printing system components and the suspension device.[0016]The amended claims provide clear and definite protection for the inventive apparatus while addressing the concerns raised during the international search, positioning the application favourably for the national phase proceedings.

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