CN112440466B - A rapid prototyping device for ultra-high molecular weight polymer - Google Patents

Abstract

The invention discloses a rapid molding device for an ultrahigh molecular weight polymer, which comprises a storage bin and a spray head arranged at the bottom of the storage bin; the heating module is used for forming a heating area with gradually increasing temperature from the top of the storage bin to one side of the bottom spray head; a feeding chamber which is formed in the storage bin corresponding to the heating area and has a feeding cross section which is changed from the storage bin to one side of the spray head; the feeding cavity comprises a first feeding cavity, a second feeding cavity and a third feeding cavity; the first feeding cavity, the second feeding cavity and the third feeding cavity are gradually reduced along the cross-sectional area of feeding of the storage bin. The invention provides a rapid forming device for an ultrahigh molecular weight polymer, which has the advantages of large adaptive temperature interval span, strong environmental adaptability and flexible and changeable printing and forming structure.

Description

A rapid prototyping device for ultra-high molecular weight polymers

technical field

The invention belongs to the technical field of polymer material molding, and in particular relates to a rapid prototyping device for ultra-high molecular weight polymers.

Background technique

3D printing is a popular concept and a kind of rapid prototyping technology, which was born in the late 1980s. This technology integrates mechanical engineering, material engineering, numerical control technology, laser technology and other technologies, and uses the material accumulation method to manufacture the prototype of parts. The principle is to first model with computer-aided design (CAD) or computer animation modeling software to form a digital model, then decompose the three-dimensional model into two-dimensional cross-sections layer by layer, and accumulate and solidify the printing materials layer by layer through the software and numerical control system. Create physical products. The mainstream methods include Stereo Lithography Apparatus (SLA), Laminated Object Manufacturing (LOM), Selective Laser Sintering (LS), and Fused Deposition Modeling (FDM). Wait. Compared with traditional manufacturing methods, 3D printing technology can ignore the complexity of the shape of product parts; manufacturing is fast, it can realize the synchronization of product design and mold production, improve research and development efficiency, and shorten the design cycle; the utilization rate of raw materials is extremely high, close to 100 %. Based on the above advantages, this technology has been increasingly widely used in industries such as automobiles, home appliances, communications, aviation, industrial modeling, medical treatment, and archaeology.

The materials used in 3D printing range from plastic materials such as photosensitive resin, ABS, ABS-like, wax type, glass fiber, etc., to metal materials such as stainless steel, aluminum alloy, iron-nickel alloy, cobalt-chromium-molybdenum alloy, etc. Compared with the past, the types have changed. It is abundant, but there is still a gap compared with the materials used in traditional manufacturing. As a new generation of engineering plastics, ultra-high molecular weight polymers have high specific strength, good toughness, wear resistance, corrosion resistance, low temperature resistance, stress cracking resistance, and Impact, anti-adhesion and self-lubrication and many other excellent properties, so it is playing an increasingly important role in industrial and agricultural production, medicine and national defense construction. However, this type of material has extremely high molecular weight, and ultra-long, entangled molecular chains, the melt is highly elastic, and the melt index is approximately zero; the molding temperature range is narrow, and it is easy to oxidative degradation; the critical shear rate is low, the friction The coefficient is small, so it is not easy to form and process.

In recent years, due to the advantages of high precision, fast speed, short cycle time, and no need for molds, laser technology has developed rapidly in the field of material processing, especially in the rapid prototyping of polymer materials, but in practical applications and research It was found that the laser rapid prototyping of ultra-high molecular weight polymers has the following problems:

First, the ultra-high molecular weight polymer is in the powder state of discrete accumulation before molding, and there are a lot of gaps between the powder particles. Since air is a poor conductor of heat, it affects the conduction of heat during molding. In addition, the fluidity of the polymer in the molten state is extremely poor, the relative position between the particles changes little, there are a large number of pores inside the molded part, and the density is low, which seriously affects the molding quality.

Second, the processing temperature range of ultra-high molecular weight polymers is narrow, and they are more sensitive to laser energy density and sintering position temperature. When the laser energy density is high, the temperature of the sintering position is too high, causing the polymer to oxidize and decompose, and the chain scission reaction occurs to form double bonds and free radicals. The breakage of molecular bonds will lead to a decrease in the performance of molded parts. At the same time, the molecular chain is also closely related to the crystallinity, and the crystallinity will affect the stiffness, tensile strength, hardness, heat resistance, solvent resistance, air tightness and chemical corrosion resistance of the product, and sometimes even directly lead to the molded parts void.

The Chinese patent application number CN201410181568.8 discloses a method and device for ultraviolet laser 3D printing of polymer materials for precise temperature control. The device includes: a constant temperature box, a laser head, a non-contact temperature monitoring device, a scanning vibrating mirror, a processing platform, a powder spreading device, processing materials, and a computer control system. The laser head adopts a double-core structure, the inner tube and the outer tube are fixed coaxially, and one or more gradient neutral filters are fixed between the two tubes. The laser transmittance of the filter is from the inner tube to the outer diameter. to lower.

The Chinese patent application number CN201510428966.X discloses a device and method for laser rapid prototyping of ultra-high molecular weight polymers. The device includes: a laser emitting end, which is used to irradiate ultra-high molecular weight polymer powder and melt it laser beam; pressure roller, used to compact the ultra-high molecular weight polymer at the laser beam sintering position; infrared thermometer, used to monitor the temperature change of the sintering position; signal processing device, used for feedback according to the temperature signal The process parameter adjustment signal is sent to the main control system; the main control system controls the laser emitting end and the pressure roller according to the process parameter adjustment signal.

Although the above-mentioned prior art has proposed a rapid prototyping method for ultra-high molecular weight polymers, there are still many problems in practical applications. For rapid prototyping, the laser of this method can only provide a temperature difference of 20-30 degrees, and cannot print materials with a large temperature difference. At the same time, the way of powder laying wastes too much material, and in most cases, new and old powders are mixed, which is harmful to molding The quality of the workpiece is affected. In addition, the method of laser sintering powder bed has strict requirements on the ambient temperature. It needs to be printed in a greenhouse or a closed space, and the method of powder laying cannot print closed structures, so the application occasions are limited.

Therefore, it is necessary to improve the deficiencies and defects of the prior art, and provide a rapid prototyping device for ultra-high molecular weight polymers, which adopts a high-temperature melting method to heat ultra-high molecular weight polymers to a molten state and extrude them. Adapt to the characteristics of large temperature range, strong adaptability to the environment, material saving, and flexible and changeable printing structure. By setting the silo as three feeding chambers, the solid or powdery ultra-high molecular weight polymerization in the silo is realized. Preheating of the material, shrinkage heating, and small hole shrinkage to accelerate extrusion, etc.; in addition, by setting a gradient heating zone, the problem of expansion and deformation of the ultra-high molecular weight polymer in the molten state and the inability to extrude is avoided.

In view of this, the present invention is proposed.

Contents of the invention

The technical problem to be solved by the present invention is to overcome the deficiencies of the prior art and provide a rapid prototyping device for ultra-high molecular weight polymers that can overcome the above problems or at least partially solve the above problems.

In order to solve the above-mentioned technical problems, the basic idea of the technical solution adopted by the present invention is: a rapid prototyping device for ultra-high molecular weight polymers, including

A silo, and a nozzle arranged at the bottom of the silo;

A heating module, forming a heating zone where the temperature gradually increases from the top of the silo to the side of the nozzle at the bottom;

Corresponding to the heating zone, a feeding chamber with a changing feeding cross-section is formed inside the silo, from the silo to the spray head side.

Wherein, the feeding chamber includes a first feeding chamber, a second feeding chamber and a third feeding chamber;

The feeding cross-sectional area of the first feeding chamber, the second feeding chamber and the third feeding chamber gradually decreases along the feeding bin;

In one embodiment, at least one of said second feed chambers is in communication with said first feed chamber;

At least one of the third feed chambers communicates with the second feed chamber.

At the same time, the first feeding chamber, the second feeding chamber and the third feeding chamber are cylindrical structures;

In one embodiment, the diameter of the first feed chamber is between 20 and 30 mm, and the length is between 100 and 200 mm;

The diameter of the second feeding cavity is between 4 and 10 mm, and the length is between 15 and 45 mm;

The diameter of the third feeding cavity is between 2.5 and 6 mm, and the length is between 50 and 90 mm.

In addition, it also includes a feeding rod, which cooperates with the silo and reciprocates in the hopper along the axial direction of the feeding rod;

In one embodiment, the silo is a hollow structure, and the first feeding cavity, the second feeding cavity and the third feeding cavity are arranged in the hollow structure of the silo;

The feeding rod is a rod-shaped structure that matches the shape of the first feeding chamber of the silo;

The nozzle is arranged at the bottom of the hollow structure;

The heating module is placed outside the silo in a ring.

Further, a limiting device is provided on the feeding rod;

The stroke of the push rod limited by the limit device is not greater than the length of the first feeding chamber;

In one embodiment, the limiting device is detachably connected to the feeding rod, and the installation position can be adjusted along the length direction of the feeding rod;

In one embodiment, the connection between the limiting device and the feeding rod is a threaded connection;

In one embodiment, the feed rod is a plunger-type rod-like structure or a threaded-type rod-like structure.

Moreover, it also includes a feeding rod, which cooperates with the silo, and reciprocates in the hopper along the axial direction of the feeding rod;

In one embodiment, the silo comprises a first annular portion and a second annular portion sleeved outside the first annular portion;

The first feeding chamber, the second feeding chamber and the third feeding chamber are arranged in the gap between the first annular portion and the second annular portion;

In one embodiment, the feeding rod is a rod-shaped structure that matches the shape of the first feeding chamber;

The spray head is connected to the second annular portion;

The heating module is arranged inside the first annular portion of the silo.

Further, a limiting device is provided on the feeding rod;

The stroke of the push rod limited by the limit device is not greater than the length of the first feeding chamber;

In one embodiment, the limiting device is detachably connected to the feeding rod, and the installation position can be adjusted along the length direction of the feeding rod;

In one embodiment, the connection between the limiting device and the feeding rod is a threaded connection;

In one embodiment, the feed rod is a plunger-type rod-like structure or a threaded-type rod-like structure.

In addition, the interior of the spray head is provided with a discharge chamber communicating with the third feeding chamber;

The front end of the discharge chamber is provided with a discharge port for extruding the ultra-high molecular weight polymer in a molten state;

In one embodiment, the diameter of the discharge cavity is 1.5 to 2.5 mm;

The diameter of the discharge port is 0.3 to 1.2mm;

In one embodiment, the spray head is detachably connected to the silo;

In one embodiment, the exterior of the spray head is provided with threads that cooperate with the silo.

Also, the heating zone is sequentially divided into at least a first heating zone, a second heating zone and a third heating zone from the top of the silo to the bottom side;

The heating temperatures of the first heating zone, the second heating zone and the third heating zone are sequentially increased;

In one embodiment, the first heating zone corresponds to the first feed chamber;

The second heating zone corresponds to the second feeding chamber;

The third heating zone corresponds to the third feeding chamber;

In one embodiment, in any of the first heating zone, the second heating zone and the third heating zone, the heating of the ultra-high molecular weight polymer is uniform heating;

In one embodiment, in said third heating zone, the ultra-high molecular weight polymer is in a molten state;

In one embodiment, the heating temperature of the heating module is between 100°C and 450°C;

In one embodiment, the heating module is a heating wire.

Further, it also includes a temperature detection device, which is arranged in the third heating zone of the heating module, and is used to detect the temperature of the heating module;

In one embodiment, the shower head is heated by heat transfer from the heating module or a heating device provided on the shower head.

After adopting the above technical solution, the present invention has the following beneficial effects compared with the prior art: the present invention adopts high-temperature melting to heat the ultra-high molecular weight polymer to a molten state and extrude it, which has a large span of adaptable temperature range and is suitable for Strong environmental adaptability, material saving, flexible and changeable printing structure, etc., by setting the silo as three feeding chambers, the preheating and shrinkage of solid or powdery ultra-high molecular weight polymers in the silo can be realized. and small hole shrinkage to accelerate extrusion, etc.; in addition, by setting a gradient heating zone, the problem of expansion and deformation of the ultra-high molecular weight polymer in the molten state and the inability to extrude is avoided.

The specific implementation manners of the present invention will be further described in detail below in conjunction with the accompanying drawings.

Description of drawings

The accompanying drawings, as a part of the present invention, are used to provide a further understanding of the present invention, and the schematic embodiments of the present invention and their descriptions are used to explain the present invention, but do not constitute improper limitations to the present invention. Apparently, the drawings in the following description are only some embodiments, and those skilled in the art can also obtain other drawings according to these drawings without creative efforts.

In the attached picture:

Fig. 1 is the first assembly schematic diagram of the rapid prototyping device of ultra-high molecular weight polymer of the present invention;

Fig. 2 is the second assembly schematic diagram of the rapid prototyping device of ultra-high molecular weight polymer of the present invention;

Fig. 3 is the third assembly schematic diagram of the rapid prototyping device of ultra-high molecular weight polymer of the present invention;

Fig. 4 is the first schematic diagram of the feed bin of the rapid prototyping device of the present invention;

Fig. 5 is the second schematic view of the feed bin of the rapid prototyping device of the present invention;

Fig. 6 is the first schematic diagram of the combined assembly of the rapid prototyping device of the present invention;

Fig. 7 is a second schematic diagram of the combined assembly of the rapid prototyping device of the present invention.

In the figure: 1, rapid prototyping device; 2, silo; 201, first feeding chamber; 202, second feeding chamber; 203, third feeding chamber; 204, first annular part; 205, second annular part; 3 , nozzle; 301, discharge cavity; 302, discharge port; 4, feed rod; 401, limit device; 5, heating module; 501, first heating zone; 502, second heating zone; 503, third heating 6. Laser emitter; 7. Rolling assembly; 701. Pressure roller; 702. First fixed seat; 703. Second fixed seat; 8. Temperature detection device; 9. Workbench; 10. Transmission system; 11 ,Control System.

It should be noted that these drawings and text descriptions are not intended to limit the concept scope of the present invention in any way, but illustrate the concept of the present invention for those skilled in the art by referring to specific embodiments.

Detailed ways

In order to make the purpose, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions in the embodiments will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. The following embodiments are used to illustrate the present invention , but not to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "upper", "lower", "front", "rear", "left", "right", "vertical", "inner", "outer" etc. The indicated orientation or positional relationship is based on the orientation or positional relationship shown in the drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the referred device or element must have a specific orientation, or in a specific orientation. construction and operation, therefore, should not be construed as limiting the invention.

In the description of the present invention, it should be noted that unless otherwise specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection or a detachable connection. Connected, or integrally connected; it may be mechanically connected or electrically connected; it may be directly connected or indirectly connected through an intermediary. Those of ordinary skill in the art can understand the specific meanings of the above terms in the present invention in specific situations.

1 to 3 are the first, second and third schematic diagrams of the rapid prototyping device 1 of the ultra-high molecular weight polymer of the present invention, as can be seen from the figure, the control system 11, the transmission system 10, the workbench 9 and the rapid prototyping device 1 constitutes a molding device for ultra-high molecular weight polymers, the control system 11 of the present invention includes a computer, and the electrical components and related equipment required to connect to the device through a data line or a wireless network device. , 3D printing and other related controls are relatively mature, so the present invention is not described in detail. Those skilled in the art can understand that the layered cutting of the molded workpiece and the data transmission to the transmission system 10 and the corresponding Control, etc., in the transmission system 10, including power components such as servo motors or stepping motors, and transmission components such as belts, pulleys, and gears, which are also common on 3D printers, so the present invention does not describe in detail. The main function of the transmission system 10 is to realize the movement of the rapid prototyping device 1 and the worktable 9 in three-dimensional space, and then realize the printing and molding of the formed workpiece. The specific transmission scheme does not affect the realization of the functions of the present invention, as long as the molding and printing in the three-dimensional space can be realized.

Further, it can be seen in the figure that the present invention is also provided with a laser emitter 6 and a temperature detection device 8, wherein the laser emitter 6 reheats the ultra-high molecular weight polymer extruded from the nozzle 3, so that it is In the process of printing and forming, it can maintain a temperature that is easy to form, and keep it for a long enough time, avoiding the problems of unstable forming structure caused by excessive heat exchange and weak bonding between ultra-high molecular weight polymers. At the same time, through A temperature detection device 8 is provided outside the rapid prototyping device 1 to accurately measure the extruding temperature of the nozzle 3. In the present invention, a temperature detection device 8 is also provided at a position close to the heating module 5 inside the hopper 2.

Furthermore, due to the physical properties of ultra-high molecular weight polymers, the adhesion of ultra-high molecular weight polymers between different printing layers is poor, so while reheating, an external force must be applied to make different printing layers The ultra-high molecular weight polymer bonding between the printing layers is more firm. As shown in FIG. The seat 703 and the pressure roller 701 are able to roll on the printing layer, thereby realizing the pressing and bonding of the ultra-high molecular weight polymer extruded by the nozzle 3 and the ultra-high molecular weight polymer of the upper layer, so that the printed structure is more stable .

Fig. 4 and Fig. 5 are the first and second schematic diagrams of the feed bin 2 of the rapid prototyping device 1 of the present invention, mainly showing the internal structure of the feed bin 2, as can be seen from Fig. 4 and Fig. 5, the feed bin 2 of the present invention There are two types of structures, which are mainly distinguished by the installation position of the heating module 5. In Fig. 4, the heating module 5 is installed outside the silo 2; in Fig. 5, the heating module 5 is installed inside the silo 2; It can be seen that inside the silo 2, corresponding to the heating zone, a first feeding chamber 201, a second feeding chamber 202 and a third feeding chamber 203 are provided;

The cross-sectional area of the first feeding chamber 201, the second feeding chamber 202 and the third feeding chamber 203 gradually decreases along the radial direction of the silo 2; in addition, the first feeding chamber 201, It is arranged inside the silo 2; at least two of the second feeding chambers 202 are arranged inside the silo 2 and communicated with the first feeding chamber 201; the third feeding chamber 203, At least two are arranged inside the silo 2 and communicate with the second feeding chamber 202; meanwhile, the first feeding chamber 201, the second feeding chamber 202 and the third feeding chamber 203 are Cylindrical structure, by setting the silo 2 as three feeding chambers, the preheating, shrinkage heating and pinhole shrinkage of the solid or powder ultra-high molecular weight polymer in the silo 2 are realized; the heating module 5 is in the Three heating zones are formed in the height direction of the silo 2, which are respectively the first heating zone 501, the second heating zone 502 and the third heating zone 503, and the first heating zone 501 corresponds to the first feeding chamber 201; The second heating zone 502 corresponds to the second feeding chamber 202; the third heating zone 503 corresponds to the third feeding chamber 203; the temperature of each heating zone is different, because the ultra-high molecular weight polymer is heated to a molten state. , easy to expand, and the extrusion force is relatively large, conventional extruders cannot realize the extrusion of ultra-high molecular weight polymers in a molten state, but the present invention makes the ultra-high molecular weight polymers After the polymer is added to the silo 2, a preheating process is obtained to avoid the expansion of the ultra-high molecular weight polymer caused by a sudden increase in temperature and the increase in extrusion pressure. At the same time, the ultra-high molecular weight polymer can still be obtained in the silo 2. Very good heating environment, in the third heating zone 503, the ultra-high molecular weight polymer is heated to a molten state, and the ultra-high molecular weight polymer in the second heating zone 502 and the first heating zone 501 will be in the third heating zone The ultra-high molecular weight polymer in the molten state of 503 is extruded from the nozzle 3. The proportion of the ultra-high molecular weight polymer in the molten state in the silo 2 is small, and there is enough preheating space to ensure extrusion while avoiding The problem of expansion of ultra-high molecular weight polymers in the molten state.

Figure 6 and Figure 7 are the first and second schematic diagrams of the combined assembly of the rapid prototyping device 1 of the present invention, mainly showing the combination during the switching process of the rapid prototyping device 1, when one of the rapid prototyping devices 1 The ultra-high molecular weight polymer After consumption, the control system 11 starts other rapid prototyping devices 1 that also contain ultra-high molecular weight polymers. As can be seen from the figure, each rapid prototyping device 1 has at least a height displacement and a horizontal displacement Two modes, the height displacement transmission system 10 is realized, and the horizontal displacement is realized through the internal combination of the rapid prototyping device 1. The horizontal displacement in Fig. 6 is mainly realized by translation, and the horizontal displacement in Fig. 7 is mainly realized by rotation. After the polymer is consumed, the rapid prototyping device 1 performs a height displacement first, and then performs a horizontal displacement to realize the departure from the working position. The rapid prototyping device 1 containing the ultra-high molecular weight polymer firstly Execute horizontal displacement. After reaching the working position, execute height displacement. In Fig. 6 and Fig. 7, only the setting position of the rapid prototyping device 1 is shown. Because the driving device and how to realize the transmission are comparatively comparative in the field of transmission. It is common, and it is not the invention point of the present invention, so too many details are not made.

The invention adopts high-temperature melting method to heat the ultra-high molecular weight polymer to a molten state and then extrude it into shape. The silo 2 is set as three feeding chambers, which realizes the preheating, shrinkage heating and pinhole shrinkage acceleration of the solid or powdery ultra-high molecular weight polymer in the silo 2; in addition, by setting the gradient heating zone, which avoids the expansion and deformation of the ultra-high molecular weight polymer in the molten state, and the problem that it cannot be extruded. The problem of poor quality; and by adding the rolling assembly 7, the ultra-high molecular weight polymer is rolled and compacted, which avoids the problem of poor viscosity of the ultra-high molecular weight polymer and weak adhesion between layers.

Embodiment one

As shown in Figures 1 to 5, a rapid prototyping device 1 for a high molecular weight polymer described in this embodiment includes a silo 2, and a nozzle 3 arranged at the bottom of the silo 2; a heating module 5 formed from The top of the silo 2 faces toward the bottom nozzle 3 side, a heating zone where the temperature gradually increases; the feeding rod 4 cooperates with the silo 2 and is inside the hopper 2 along the axial direction of the feeding rod 4 reciprocating movement; wherein, inside the silo 2, corresponding to the heating zone, a first feeding chamber 201, a second feeding chamber 202 and a third feeding chamber 203 are provided; the first feeding chamber 201, the second feeding chamber The cross-sectional area of the second feeding chamber 202 and the third feeding chamber 203 decreases gradually along the radial direction of the silo 2 .

The invention adopts high-temperature melting method to heat the ultra-high molecular weight polymer to a molten state and then extrude it into shape. The silo 2 is set as three feeding chambers to realize the preheating, shrinkage heating and pinhole shrinkage of the solid or powder ultra-high molecular weight polymer in the silo 2 to accelerate extrusion. It will become swollen and viscous and not easy to extrude. By setting a number of small hole structures in the second feeding chamber 202 and the third feeding chamber 203, the ultra-high molecular weight polymer in the high temperature state can be obtained Higher extrusion pressure, while avoiding the thermal expansion of ultra-high molecular weight polymers caused by excessive unit volume, and the phenomenon that it cannot be extruded.

Embodiment two

As shown in Figures 1 to 5, this embodiment is based on the first embodiment above. The first feeding chamber 201 in this embodiment is arranged inside the silo 2; the second feeding chamber 202 is at least Two are arranged inside the silo 2 and communicate with the first feeding chamber 201; at least two of the third feeding chambers 203 are arranged inside the silo 2 and communicate with the second feeding chamber 203. The feeding cavity 202 is connected.

Embodiment Three

As shown in Figures 1 to 5, this embodiment is based on the first or second embodiment above, the first feeding chamber 201, the second feeding chamber 202 and the third feeding chamber 203 in this embodiment It is a cylindrical structure; the diameter of the first feeding chamber 201 is between 20 and 30 mm, and the length is between 100 and 200 mm; the diameter of the second feeding chamber 202 is between 4 and 10 mm, and the length is between between 15 and 45 mm; the diameter of the third feeding cavity 203 is between 2.5 and 6 mm, and the length is between 50 and 90 mm.

Embodiment four

As shown in Figures 1 to 5, this embodiment is based on any one of the above-mentioned embodiments 1 to 3, the silo 2 in this embodiment is a hollow structure, the first feeding chamber 201, the The second feeding chamber 202 and the third feeding chamber 203 are arranged in the hollow structure of the silo 2; 201 are matched in shape; the spray head 3 is arranged at the bottom of the hollow structure; the heating module 5 is placed outside the silo 2 .

Alternatively, the silo 2 includes a first annular portion 204 and a second annular portion 205 sleeved outside the first annular portion 204; the first feeding chamber 201, the second feeding chamber 202 and the The third feeding cavity 203 is arranged in the gap between the first annular portion 204 and the second annular portion 205; The cavity 201 is matched in shape; the spray head 3 is connected to the second annular portion 205 ; the heating module 5 is arranged inside the first annular portion 204 of the silo 2 .

Further, a limiting device 401 is provided on the feeding rod 4; the stroke of the pushing rod limited by the limiting device 401 is not greater than the length of the first feeding chamber 201; the limiting device 401 is in contact with the The feeding rod 4 is detachably connected, and the installation position can be adjusted along the length direction of the feeding rod 4; the connection between the limiting device 401 and the feeding rod 4 is a screw connection.

Embodiment five

This embodiment is based on the fourth embodiment above, and the feeding rod 4 in this embodiment is a plunger-type rod-shaped structure or a threaded-type rod-shaped structure.

Embodiment six

As shown in Figures 1 to 5, this embodiment is based on any one of the above-mentioned embodiments 1 to 5, and the inside of the spray head 3 in this embodiment is provided with a nozzle that communicates with the third feeding chamber 203. Discharge cavity 301; the front end of the discharge cavity 301 is provided with a discharge port 302 for extruding the ultra-high molecular weight polymer in molten state; the diameter of the discharge cavity 301 is 1.5 to 2.5 mm; the discharge port The diameter of 302 is 0.3 to 1.2 mm; the nozzle 3 is detachably connected to the bin 2;

Specifically, the discharge port 302 of the nozzle 3 is drilled by numerical control electric spark, and the exterior of the nozzle 3 can be welded with the discharge chamber 301 by argon arc welding, or integrally formed. In use, if the nozzle 3 is blocked or the discharge is not smooth due to some reasons, the continuous discharge can be ensured by replacing the nozzle 3, or part of the discharge port 302 can be cut off by wire cutting, and then through argon arc welding Welded into a new nozzle 3. This setting is due to the fact that the difficulty of processing the millimeter-level discharge port 302 is less than the difficulty of directly replacing the entire nozzle 3 .

Embodiment seven

As shown in Figures 1 to 5, this embodiment is based on any one of the above-mentioned embodiments 1 to 6, the heating zone in this embodiment, from the top of the silo 2 to the bottom side, Sequentially divided into at least the first heating zone 501, the second heating zone 502 and the third heating zone 503; the heating temperatures of the first heating zone 501, the second heating zone 502 and the third heating zone 503 are successively increased ; The first heating zone 501 corresponds to the first feeding cavity 201; the second heating zone 502 corresponds to the second feeding cavity 202; the third heating zone 503 corresponds to the third feeding cavity 203; In any heating zone in the first heating zone 501, the second heating zone 502 and the third heating zone 503, the heating of the ultra-high molecular weight polymer is uniform heating; in the third heating zone 503 , the ultra-high molecular weight polymer is in a molten state; the heating temperature of the heating module 5 is between 100° C. and 450° C.; the heating module 5 is a heating wire.

Wherein, the heating zone is sequentially divided into a first heating zone 501, a second heating zone 502 and a third heating zone 503 from the top of the silo 2 to the bottom side; The ultra-high molecular weight polymer is in the original state when it is put into the silo 2; the ultra-high molecular weight polymer in the second heating zone 502 is in a transitional state from the original state to a molten state; the third heating zone The ultra-high molecular weight polymer in 503 is in a molten state.

Fig. 4 and Fig. 5 are the first and second schematic diagrams of the feed bin 2 of the rapid prototyping device 1 of the present invention, mainly showing the internal structure of the feed bin 2, as can be seen from Fig. 4 and Fig. 5, the feed bin 2 of the present invention There are two types of structures, which are mainly distinguished by the installation position of the heating module 5. In Fig. 4, the heating module 5 is installed outside the silo 2; in Fig. 5, the heating module 5 is installed inside the silo 2; It can be seen that the heating module 5 is formed with three sections of heating zones in the height direction of the silo 2, which are respectively the first heating zone 501, the second heating zone 502 and the third heating zone 503. The temperature of each heating zone is different, due to After the ultra-high molecular weight polymer is heated to the molten state, it is easy to expand, and the extrusion force is relatively large. Conventional extruders cannot realize the extrusion of the ultra-high molecular weight polymer in the molten state. The zone is set to three, so that after the ultra-high molecular weight polymer is added to the silo 2, the preheating process is obtained, so as to avoid the expansion of the ultra-high molecular weight polymer due to a sudden increase in temperature and the increase in extrusion pressure. At the same time, the ultra-high molecular weight polymer The polymer can still obtain a good heating environment in the silo 2. In the third heating zone 503, the ultra-high molecular weight polymer is heated to a molten state. Molecular weight polymer The ultra-high molecular weight polymer in the molten state in the third heating zone 503 is extruded from the nozzle 3, and the proportion of the ultra-high molecular weight polymer in the molten state to the bin 2 is small, and there is enough space for preheating , to ensure extrusion while avoiding the problem of expansion of ultra-high molecular weight polymers in molten state.

Embodiment eight

As shown in Figures 1 to 5, this embodiment is based on any one of the above-mentioned embodiments from Embodiment 1 to Embodiment 7, and this embodiment also includes a temperature detection device 8, which is arranged on the first heating module 5. The three heating zones 503 are used to detect the temperature of the heating module 5 ; the shower head 3 is heated by the heat transfer of the heating module 5 or the heating device installed on the shower head 3 . By setting the temperature detection device 8 outside the rapid prototyping device 1, the extrusion temperature of the nozzle 3 can also be accurately measured. In the present invention, a temperature detection device 8 is also provided at a position close to the heating module 5 inside the silo 2 .

Embodiment nine

As shown in Figures 1 to 5, this embodiment is based on any one of the above-mentioned embodiments from Embodiment 1 to Embodiment 8. A rapid prototyping device 1 for ultra-high molecular weight polymers described in this embodiment also includes The rolling assembly 7 is used to compact the ultra-high molecular weight polymer extruded by the nozzle 3; the rolling assembly 7 includes a first fixing seat 702, and the silo 2, and/or, the The nozzle 3 is connected; the second fixed seat 703 is connected with the first fixed seat 702; the pressure roller 701 is arranged inside the second fixed seat 703;

Preferably, the pressing roller 701 realizes compaction of the ultra-high molecular weight polymer by rolling on the surface of the ultra-high molecular weight polymer extruded from the nozzle 3 .

Further, the first fixing seat 702 is a fixed structure that is connected to the silo 2 and/or the spray head 3 and is arranged in a plane, and the fixed structure that is arranged in a plane described in this implementation It can be understood as a circular or square planar structure arranged on a plane. The purpose of setting it as a plane is to provide more installation space for the second fixing seat 703, and reserve enough space to deal with the different sizes of the The replacement of the pressure roller 701; the second fixed seat 703 is at least one cylindrical hollow structure arranged on the first fixed seat 702; the pressure roller 701 is capable of being placed in the second fixed seat 703 rolling balls;

Preferably, the number of the second fixing seat 703 on the first fixing seat 702 is 8 to 20;

More preferably, the connection between the second fixing base 703 and the first fixing base 702 is a detachable connection.

Specifically, those skilled in the art realize the adjustment of different numbers of pressing rollers 701 by disassembling the first fixing seat 702 and the second fixing seat 703, and can also adjust pressing rollers 701 of different diameters to meet the needs of different rapid prototyping workpieces. Compression is required, and the disassembly between the first fixing seat 702 and the second fixing seat 703 can be realized by interference or clearance fit, or by technical means such as clip joint and screw connection.

Figures 1 to 3 are the first, second and third schematic diagrams of the rapid prototyping device 1 for ultra-high molecular weight polymers of the present invention. The adhesion of ultra-high molecular weight polymers between different printing layers is poor, so an external force must be applied to it during the second heating to make the ultra-high molecular weight polymers between different printing layers more firmly bonded, as shown in Figure 3 As shown, a rolling assembly 7 is provided near the nozzle 3. The rolling assembly 7 includes a pressure roller 701, a first fixed seat 702 and a second fixed seat 703. The pressure roller 701 is capable of rolling on the printing layer, thereby realizing extrusion of the nozzle 3. The pressed and bonded ultra-high molecular weight polymer and the ultra-high molecular weight polymer of the previous layer make the printed structure more stable.

Embodiment ten

This embodiment is based on any of the embodiments described in the above-mentioned Embodiment 1 to Embodiment 9. A rapid prototyping method for ultra-high molecular weight polymers described in this embodiment includes:

Workbench 9, used to hold the ultra-high molecular weight polymer extruded by the rapid prototyping device 1;

The transmission system 10 drives the rapid prototyping device 1 and the worktable 9 to move in three-dimensional space;

The control system 11 is respectively connected with the rapid prototyping device 1, the workbench 9 and the transmission system 10, and stores the three-dimensional shape information of the formed workpiece;

Also includes

Step 101, after filling the ultra-high molecular weight polymer into the bin 2 of the rapid prototyping device 1, place the rapid prototyping device 1 at a working position and connect it to the transmission system 10;

Step 102, select the required molding workpiece in the control system 11, and set the printing parameters;

Step 103, through the control system 11, slice the three-dimensional shape of the required molded workpiece into slices, convert it into two-dimensional layered cross-sectional information, and obtain the motion track scanned layer by layer along the height direction;

Step 104, start the heating module 5 of the rapid prototyping device 1, the temperature detection device 8 detects the temperature of the heating module 5 in real time, and transmits the data to the control system 11;

Step 105, when the temperature of the heating module 5 reaches the preset temperature, the control system 11 transmits the motion trajectory of the two-dimensional layered cross-section of the molded workpiece to the transmission system 10, and the transmission system 10 transmits the The rapid prototyping device 1 moves to the initial position;

Step 106, the feeding rod 4 moves from the top of the silo 2 to the bottom, pushing the ultra-high molecular weight polymer in the silo 2, and the ultra-high molecular weight polymer in a molten state is extruded from the nozzle 3;

Step 1061, the control system 11 activates the laser emitter 6, and the laser emitter 6 reheats the ultra-high molecular weight polymer extruded by the nozzle 3;

Step 107, the transmission system 10 completes the printing of the current layer according to the trajectory of the two-dimensional layered cross-section of the molded workpiece;

Step 1071, the rolling assembly 7 compacts the ultra-high molecular weight polymer extruded from the nozzle 3 as the rapid prototyping device 1 moves;

Step 108, after the current layer is printed, the transmission system 10 moves the rapid prototyping device 1 to the initial position, and moves the rapid prototyping device 1 or the workbench 9 to the next layer along the height direction;

Step 109, repeating steps 106 to 108 until the overall printing of the formed workpiece is completed;

Step 110: Take out the workpiece to obtain the final shaped workpiece.

Embodiment Eleven

This embodiment is based on the above-mentioned embodiment ten. In step 104 of this embodiment, the heating module 5 corresponds to the magazine 2 of the rapid prototyping device 1 and forms a heating zone; the heating zone is formed from the The side of the top of the silo 2 towards the bottom is at least divided into a first heating zone 501, a second heating zone 502 and a third heating zone 503; the ultra-high molecular weight polymer in the first heating zone 501 is placed The original state when entering the silo 2; the ultra-high molecular weight polymer in the second heating zone 502 is in the transition state from the original state to the molten state; the ultra-high molecular weight polymer in the third heating zone 503 , in a molten state.

Embodiment 12

This embodiment is based on the above-mentioned tenth or eleventh embodiment, step 104 in this embodiment also includes step 1041, heating the workbench 9 until the set temperature; The set temperature is from 20°C to 100°C.

Embodiment Thirteen

This embodiment is based on any one of the above-mentioned embodiments ten to twelve, and the preset temperature range in step 105 in this embodiment is between 100°C and 450°C; ultra-high molecular weight polymerization The material is one or a combination of silk, powder and pellets.

Embodiment Fourteen

This embodiment is based on any one of the tenth to thirteenth embodiments described above. In step 1061 of this embodiment, the laser emitted by the laser emitter 6 is an annular hollow beam; the laser emitter 6. The emitted annular hollow beam can be emitted to the position of the ultra-high molecular weight polymer extruded by the nozzle 3; the hollow part of the annular hollow beam is not smaller than the corresponding ultra-high molecular weight polymer extruded by the nozzle 3 diameter.

Embodiment 15

This embodiment is based on any of the embodiments described in the above tenth to fourteenth embodiments. In step 1071 of this embodiment, the rolling assembly 7 includes a first fixing seat 702, which is connected to the silo 2 , and/or, the spray head 3 is connected; the second fixed seat 703 is connected with the first fixed seat 702; the pressure roller 701 is arranged inside the second fixed seat 703;

Preferably, the pressing roller 701 realizes compaction of the ultra-high molecular weight polymer by rolling on the surface of the ultra-high molecular weight polymer extruded from the nozzle 3 .

Further, the first fixing seat 702 is a fixed structure that is connected to the silo 2 and/or the spray head 3 and is arranged in a plane, and the fixed structure that is arranged in a plane described in this implementation It can be understood as a circular or square planar structure arranged on a plane. The purpose of setting it as a plane is to provide more installation space for the second fixing seat 703;

And reserve enough space to deal with the replacement of the pressure rollers 701 of different sizes; the second fixed seat 703 is at least one cylindrical hollow structure arranged on the first fixed seat 702; the pressure roller 701 is a ball capable of rolling in the second fixing seat 703;

Preferably, the number of the second fixing seat 703 on the first fixing seat 702 is 8 to 20;

More preferably, the connection between the second fixing base 703 and the first fixing base 702 is a detachable connection.

Specifically, those skilled in the art realize the adjustment of different numbers of pressing rollers 701 by disassembling the first fixing seat 702 and the second fixing seat 703, and can also adjust pressing rollers 701 of different diameters to meet the needs of different rapid prototyping workpieces. Compression is required, and the disassembly between the first fixing seat 702 and the second fixing seat 703 can be realized by interference or clearance fit, or by technical means such as clamping connection and screw connection.

Embodiment sixteen

This embodiment is based on any of the embodiments described in the tenth to fifteenth embodiments above. Step 108 in this embodiment also includes step 1081, the rapid prototyping device 1 for containing ultra-high molecular weight polymers at least two; when the ultra-high molecular weight polymer in one of the rapid prototyping devices 1 is consumed, the control system 11 starts other rapid prototyping devices 1 that also contain ultra-high molecular weight polymers, and Jump back to step 104 to start execution.

Embodiment 17

This embodiment is based on the above sixteenth embodiment. In this embodiment, during the switching process of the rapid prototyping device 1 in step 1081, each rapid prototyping device 1 has at least two modes of height displacement and horizontal displacement; After the ultra-high molecular weight polymer is consumed, the rapid prototyping device 1 performs a height displacement first, and then performs a horizontal displacement, thereby realizing the departure from the working position; the rapid prototyping device containing the ultra-high molecular weight polymer 1. Perform horizontal displacement first, and then perform height displacement after reaching the working position.

Figure 6 and Figure 7 are the first and second schematic diagrams of the combined assembly of the rapid prototyping device 1 of the present invention, mainly showing the combination during the switching process of the rapid prototyping device 1, when one of the rapid prototyping devices 1 The ultra-high molecular weight polymer After consumption, the control system 11 starts other rapid prototyping devices 1 that also contain ultra-high molecular weight polymers. As can be seen from the figure, each rapid prototyping device 1 has at least a height displacement and a horizontal displacement Two modes, the height displacement transmission system 10 is realized, and the horizontal displacement is realized through the internal combination of the rapid prototyping device 1;

The horizontal displacement in Figure 6 is mainly realized by translation, and the horizontal displacement in Figure 7 is mainly realized by rotation. After the ultra-high molecular weight polymer is consumed, the rapid prototyping device 1 first performs height displacement, and then performs horizontal displacement, thereby realizing Leaving from the working position, the rapid prototyping device 1 containing the ultra-high molecular weight polymer first performs a horizontal displacement, and after reaching the working position, performs a height displacement;

In Fig. 6 and Fig. 7, only the setting position of the rapid prototyping device 1 is shown, because the driving device and how to realize the transmission are relatively common in the field of transmission, and are not the invention point of the present invention, so no further details have been made. Too much to repeat.

In the description provided herein, numerous specific details are set forth. However, it is understood that embodiments of the invention may be practiced without these specific details. In some instances, well-known methods, structures and techniques have not been shown in detail in order not to obscure the understanding of this description.

In addition, those skilled in the art will understand that although some embodiments described herein include some features contained in other embodiments but not others, the combination of features of different embodiments also means that they are within the scope of the present invention. within the scope of protection and form different embodiments. For example, in the above embodiments, those skilled in the art can use them in combination according to the known technical solutions and the technical problems to be solved in this application.

The above description is only a preferred embodiment of the present invention, and does not limit the present invention in any form. Although the present invention has been disclosed as above with preferred embodiments, it is not intended to limit the present invention. Anyone familiar with the technology of this patent Without departing from the scope of the technical solution of the present invention, personnel can use the technical content of the above prompts to make some changes or modify them into equivalent embodiments with equivalent changes. In essence, any simple modifications, equivalent changes and modifications made to the above embodiments still fall within the scope of the solutions of the present invention.

Claims (23)

1. A rapid prototyping device for ultra-high molecular weight polymers, characterized in that: comprising A silo (2), and a nozzle (3) arranged at the bottom of the silo (2); The heating module (5) forms a heating zone where the temperature gradually increases from the top of the silo (2) to the side of the nozzle (3) at the bottom; Corresponding to the heating zone, a feeding chamber with a changing feeding cross section is formed inside the silo (2) from the silo (2) to the nozzle (3) side; The feeding chamber includes a first feeding chamber (201), a second feeding chamber (202) and a third feeding chamber (203); The feeding cross-sectional area of the first feeding chamber (201), the second feeding chamber (202) and the third feeding chamber (203) gradually decreases along the feeding bin (2); It also includes a feed rod (4), which cooperates with the feed bin (2) and reciprocates in the feed bin (2) along the axial direction of the feed rod (4); A limiting device (401) is arranged on the feeding rod (4), and the stroke of the feeding rod (4) limited by the limiting device (401) is not greater than the length of the first feeding chamber (201); The limiting device (401) is detachably connected to the feeding rod (4), and the installation position can be adjusted along the length direction of the feeding rod (4). 2. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 1, is characterized in that: At least one of the second feeding chambers (202) communicates with the first feeding chamber (201); At least one of the third feeding chambers (203) communicates with the second feeding chamber (202). 3. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 2, is characterized in that: described first feed chamber (201), described second feed chamber (202) and described 3rd feed chamber The cavity (203) is a cylindrical structure. 4. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 3, is characterized in that: The diameter of the first feeding cavity (201) is between 20 and 30 mm, and the length is between 100 and 200 mm; The diameter of the second feeding cavity (202) is between 4 and 10m, and the length is between 15 and 45mm; The diameter of the third feeding cavity (203) is between 2.5 and 6 mm, and the length is between 50 and 90 mm. 5. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to any one of claims 1-4, characterized in that: The silo (2) is a hollow structure, the first feeding cavity (201), the second feeding cavity (202) and the third feeding cavity (203) are arranged in the silo (2) inside a hollow structure; The feeding rod (4) is a rod-shaped structure that matches the shape of the first feeding chamber (201) of the silo (2); The nozzle (3) is arranged at the bottom of the hollow structure; The heating module (5) is placed outside the storage bin (2). 6. A rapid prototyping device for ultra-high molecular weight polymers according to claim 5, characterized in that: the connection between the limiting device (401) and the feeding rod (4) is a threaded connection. 7. A rapid prototyping device for ultra-high molecular weight polymers according to claim 6, characterized in that: the feeding rod (4) is a plunger-type rod-shaped structure or a threaded-type rod-shaped structure. 8. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to any one of claims 1-4, characterized in that: The silo (2) includes a first annular portion (204) and a second annular portion (205) sleeved outside the first annular portion (204); The first feeding chamber (201), the second feeding chamber (202) and the third feeding chamber (203) are arranged on the first annular portion (204) and the second annular portion (205) ) between the gaps. 9. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 8, characterized in that: the feeding rod (4) is a rod-shaped structure, which is similar to the shape of the first feeding cavity (201). Cooperate; The spray head (3) is connected with the second annular portion (205); The heating module (5) is arranged inside the first annular portion (204) of the silo (2). 10. A rapid prototyping device for ultra-high molecular weight polymers according to claim 9, characterized in that: the connection between the limiting device (401) and the feeding rod (4) is a screw connection. 11. A rapid prototyping device for ultra-high molecular weight polymers according to claim 10, characterized in that: the feeding rod (4) is a plunger-type rod-shaped structure or a threaded-type rod-shaped structure. 12. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 1, is characterized in that: The interior of the spray head (3) is provided with a discharge chamber (301) communicating with the third feed chamber (203); The front end of the discharge cavity (301) is provided with a discharge port (302) for extruding the ultra-high molecular weight polymer in molten state. 13. A rapid prototyping device for ultra-high molecular weight polymers according to claim 12, characterized in that: the diameter of the discharge cavity (301) is 1.5 to 2.5 mm; The diameter of the outlet (302) is 0.3 to 1.2 mm. 14. A rapid prototyping device for ultra-high molecular weight polymers according to claim 13, characterized in that: the spray head (3) is detachably connected to the feed bin (2). 15. A rapid prototyping device for ultra-high molecular weight polymers according to claim 14, characterized in that: the outside of the spray head (3) is provided with threads that cooperate with the silo (2). 16. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 1, characterized in that: The heating zone is at least divided into a first heating zone (501), a second heating zone (502) and a third heating zone (503) sequentially from the top of the silo (2) to the bottom side; The heating temperatures of the first heating zone (501), the second heating zone (502) and the third heating zone (503) are sequentially increased. 17. A rapid prototyping device for ultra-high molecular weight polymers according to claim 16, characterized in that: the first heating zone (501) corresponds to the first feeding chamber (201); The second heating zone (502) corresponds to the second feeding cavity (202); The third heating zone (503) corresponds to the third feeding cavity (203). 18. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 17, characterized in that: in the first heating zone (501), the second heating zone (502) and the third heating zone In any heating zone in the heating zone (503), the heating of the ultra-high molecular weight polymer is uniform heating. 19. A rapid prototyping device for ultra-high molecular weight polymers according to claim 18, characterized in that: in the third heating zone (503), the ultra-high molecular weight polymers are in a molten state. 20. A rapid prototyping device for ultra-high molecular weight polymers according to claim 19, characterized in that: the heating temperature of the heating module (5) is between 100°C and 450°C. 21. A rapid prototyping device for ultra-high molecular weight polymers according to claim 20, characterized in that: the heating module (5) is a heating wire. 22. The rapid prototyping device of a kind of ultra-high molecular weight polymer according to claim 16, characterized in that: it also includes a temperature detection device (8), which is arranged on the third heating module of the heating module (5). In the zone (503), it is used to detect the temperature of the heating module (5). 23. A rapid prototyping device for ultra-high molecular weight polymers according to claim 22, characterized in that: the spray head (3) passes through the heat transfer of the heating module (5) or is arranged on the spray head (3) ) The heating device realizes the heating of the shower head (3).

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