Temperature control system for 3D printing and printing platform and printing cabin comprising temperature control system

Abstract

The invention relates to a temperature control system for 3D printing. The temperature control system comprises a semiconductor chilling plate, a cooling liquid circulation assembly, a refrigerant circulation assembly, a heat dissipation piece tightly attached to one end of the semiconductor chilling plate, and a temperature control unit electrically connected with the semiconductor chilling plate. A cooling liquid flow channel is arranged in the heat dissipation piece, the cooling liquid circulation assembly is used for supplying cooling liquid to the heat dissipation piece, and the refrigerant circulation assembly is used for cooling the cooling liquid. The temperature control system is of a three-section refrigeration design, heat dissipation of the hot end of the semiconductor chilling plate is accelerated by arranging two sets of circulation systems, so that the refrigeration effect of the cold end of the semiconductor chilling plate is improved, the purposes of faster cooling and lower temperature are achieved, the temperature control range of the 3D printing temperature control system is wider, and the temperature control efficiency is improved. Therefore, the requirements of complex biological material printing and organ chip manufacturing are met.

Description

Technical Field

[0001] This invention relates to the field of biomaterial 3D printing technology, and more specifically, to a temperature control system for 3D printing and a printing platform and printing chamber containing the same. Background Technology

[0002] Bioprinting technology, as a key means to achieve high-precision, high-throughput biomaterial manufacturing, is receiving widespread attention. However, existing bioprinting technologies still have shortcomings in material deposition and performance control under complex environments, especially in the fabrication of organ-on-a-chip systems. Precise control of the printing performance of bio-inks (such as cell suspensions and hydrogels) under various temperature conditions is required to ensure the integrity of the printed structure and cell viability. The printing platform, as the core component carrying the printing material, and the printing chamber, a crucial part of the 3D printer, provide a relatively independent printing environment. Both directly affect the accuracy, stability, and functionality of the printed structure. Therefore, temperature control within the printing platform and printing chamber is particularly important.

[0003] In existing technologies, temperature control is mostly achieved through thermoelectric coolers (SCUs). However, the cooling effect of SCUs is limited by the heat dissipation efficiency of the hot end, resulting in a significant reduction in the temperature difference between the hot and cold ends. For example, for every 10°C increase in the hot end temperature, the cold end temperature may rise by 8–10°C. Currently, heat dissipation methods for the hot end of SCUs are often quite limited, such as using heat sinks, air cooling, or water cooling for auxiliary heat dissipation. However, this single method results in low heat dissipation efficiency at the hot end, leading to limited cooling effect at the cold end and a narrow temperature control range, which cannot meet the printing requirements of certain special materials. Furthermore, in situations requiring rapid temperature switching (such as rapid cooling from high to low temperatures), the system's response speed may not be sufficient. Summary of the Invention

[0004] To overcome the problems in the prior art, this invention provides a temperature control system for 3D printing, as well as a printing platform and printing chamber containing the same. The temperature control system of this invention forms a three-stage cooling design by setting up a semiconductor cooling chip, a coolant circulation assembly, a refrigerant circulation assembly, and a heat sink, which includes two circulation systems. This can accelerate the heat dissipation of the hot end of the semiconductor cooling chip, thereby improving the cooling effect of the semiconductor cooling chip and achieving the purpose of faster cooling and lower temperature. This makes the temperature control range of the 3D printing temperature control system wider and its application range broader.

[0005] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a temperature control system for 3D printing, including a semiconductor cooling chip, a coolant circulation assembly, a refrigerant circulation assembly, a heat sink tightly attached to one end of the semiconductor cooling chip, and a temperature control unit electrically connected to the semiconductor cooling chip; the heat sink is provided with a coolant flow channel, the coolant circulation assembly is used to supply coolant to the heat sink, and the refrigerant circulation assembly is used to cool the coolant in the coolant circulation assembly.

[0006] In the above technical solution, the temperature control unit controls the thermoelectric cooler to cool or heat by supplying a positive or reverse voltage. Specifically, supplying a positive voltage cools one end of the thermoelectric cooler, causing its temperature to drop (the cold end), while the other end heats up (the hot end). The heat from the hot end is transferred to the heat sink in close contact with it and carried away by the coolant flowing through the coolant channels within the heat sink, thus cooling the hot end. After the thermoelectric cooler is powered and stabilized, the temperature difference between the cold and hot ends remains constant. The cooling capacity depends on the temperature of the hot end; therefore, the better the heat dissipation effect of the heat sink, the better the cooling capacity of the thermoelectric cooler. This invention, through a three-stage cooling design, includes two separate circulation systems for the refrigerant and coolant, enabling excellent temperature control for the 3D printer. Specifically, the refrigerant is first cooled by the refrigerant circulation assembly, and then the cooled refrigerant further cools the coolant. The lower-temperature coolant allows the heat sink to quickly remove more heat from the hot end, thus improving the cooling effect of the coolant on the hot end of the thermoelectric cooler. This lowers the temperature of the hot end, allowing the cold end to reach a lower cooling temperature more quickly, achieving a rapid transition from high to low temperature. When heating is needed, both the coolant and refrigerant circulation assemblies are stopped. A reverse voltage is then input to the thermoelectric cooler via the temperature control unit, swapping the hot and cold ends of the thermoelectric cooler. Since no coolant participates in the circulation and heat dissipation, the temperature rises, achieving the purpose of heating.

[0007] Furthermore, the coolant circulation assembly includes a heat exchanger for exchanging heat with the coolant, and the refrigerant circulation assembly includes a compressor and a radiator connected to the compressor. The compressor inlet is connected to the refrigerant outlet of the heat exchanger, and the radiator's refrigerant outlet is connected to the refrigerant inlet of the heat exchanger. Under the sequential action of the compressor and radiator, the refrigerant can be rapidly cooled and enters the heat exchanger from the refrigerant inlet to exchange heat with the coolant, thereby cooling the coolant. After heat exchange, the refrigerant re-enters the compressor from the refrigerant outlet of the heat exchanger for further processing. Through the action of the compressor and radiator, a lower-temperature refrigerant is obtained, achieving rapid cooling of the coolant and ultimately improving the heat dissipation effect of the heat sink.

[0008] Furthermore, the radiator includes several heat dissipation units, heat dissipation pipes surrounding the heat dissipation units, and a fan; each heat dissipation unit is formed by multiple heat dissipation fins, and the heat dissipation pipes pass through all the heat dissipation fins and form a multi-layer structure by surrounding the heat dissipation fins radially and axially; there are at least two heat dissipation units arranged radially, with the heat dissipation fins of adjacent heat dissipation units staggered; the inlet and outlet of the heat dissipation pipes are the inlet and outlet of the radiator, respectively. The refrigerant flows through the heat dissipation pipes and the heat dissipation fins, and the heat dissipation fins exchange heat with the outside environment to achieve cooling of the refrigerant, wherein the fan can accelerate the heat exchange speed of the heat dissipation fins.

[0009] Furthermore, the fan includes a first fan blade, a second fan blade, and a motor that drives the first and second fan blades to rotate. The first fan blade is located within the cavity formed by the heat dissipation unit and extends axially. The second fan blade is located at one end of the heat dissipation unit and extends radially. The radial projections of the heat sinks are all within the coverage area of ​​the first fan blade. The axial projections of the heat sinks are all within the coverage area of ​​the second fan blade. The heat dissipation unit, formed by multiple heat sinks, forms an inner cavity at its center. The first fan blade is located within the inner cavity. When the motor drives the first fan blade to rotate, it can draw in heat from around the heat sink, thereby cooling the heat sink. At the same time, the second fan blade discharges the air drawn in by the first fan blade from one end, realizing the circulation of the cooling airflow. Since air enters or exits through each air duct formed between adjacent heat sinks when the first fan blade is working, the heat dissipation function of each heat sink can be fully utilized, improving the heat dissipation effect of the radiator.

[0010] Furthermore, the coolant circulation assembly also includes a coolant tank and a pump body. The outlet of the coolant tank is connected to the pump body, the pump body is connected to the inlet of the heat exchanger, the outlet of the heat exchanger is connected to the inlet of the coolant flow channel, and the inlet of the coolant tank is connected to the outlet of the coolant flow channel. The pump body draws coolant from the coolant tank, allowing the coolant to pass through the heat exchanger for cooling before flowing into the coolant flow channel to cool the heat dissipation components. Then, the coolant flows back to the coolant tank from the outlet of the coolant flow channel, thus achieving coolant circulation and cooling.

[0011] A printing platform includes a platform receiving plate, a heat insulation plate, and the aforementioned temperature control system. A thermoelectric cooler and a heat sink are located between the platform receiving plate and the heat insulation plate. One end of the thermoelectric cooler is in close contact with the bottom surface of the platform receiving plate. During cooling operation, the end of the thermoelectric cooler in contact with the bottom surface of the platform receiving plate is the cold end, allowing direct temperature control of the platform receiving plate to lower its temperature to near that of the cold end. The end of the thermoelectric cooler connected to the heat sink is the hot end. Through the cooling method described above, the cooling capacity of the cold end is enhanced, thus enabling the platform receiving plate to reach a lower temperature more quickly.

[0012] A printing chamber includes a housing and the aforementioned temperature control system; a thermoelectric cooler is installed inside the housing and used to control the temperature inside the housing. One end of the thermoelectric cooler is in close contact with a heat sink, and the other end contacts the air inside the housing, directly cooling or heating the air inside the housing, causing the temperature inside the housing to decrease or increase and reach a target temperature.

[0013] Furthermore, the housing is at least divided into a printing chamber, an airflow chamber, and a circulation chamber. The airflow chamber has a through hole connecting to the printing chamber, and the circulation chamber is connected to both the airflow chamber and the printing chamber via a first connecting port and a second connecting port, respectively. The thermoelectric cooler is installed inside the airflow chamber, and a fan is installed inside the airflow chamber. By dividing the housing into different chambers, the thermoelectric cooler is used to cool or heat the air inside the housing. The airflow generated by the fan can form a fixed flow path, achieving more efficient cooling or heating of the printing chamber. At the same time, the printing chamber and the airflow chamber are separated to prevent the heat generated by the hot end of the thermoelectric cooler from affecting the printing chamber.

[0014] Furthermore, the airflow cavity is also equipped with a heat exchanger that is in close contact with the other end of the semiconductor cooling chip; an air duct is provided inside the heat exchanger, and the heat exchanger is located between the fan outlet and the first connecting port; a gap is left between the fan outlet and the heat exchanger and it faces the inlet of the air duct, and the fan inlet is connected to the through hole. Inside the airflow cavity, the airflow blown out by the fan outlet passes through the heat exchanger to form an airflow. The airflow enters the flow cavity from the first connecting port, and then enters the printing cavity from the flow cavity, accelerating the rate at which the temperature inside the chamber decreases or increases, allowing for faster temperature conversion within the chamber. The gap between the fan outlet and the heat exchanger allows the airflow blown by the fan to diffuse before contacting the heat exchanger, enabling the fan airflow to cover a larger area of ​​the heat exchanger and produce more airflow at the same time.

[0015] Furthermore, the airflow cavity is located on one side of the printing cavity, the circulation cavity is located above the printing cavity, and at least one side of the housing is provided with a heat insulation cavity. Since the density of cold air is greater than that of indoor air or warmer air, the cold air will move downwards. By arranging the circulation cavity above the printing cavity, the cold air, in addition to moving downwards under the action of the fan, will also move downwards due to its own density, accelerating its filling of the printing cavity to reduce the temperature of the printing cavity. Furthermore, combined with the suction effect of the fan, the airflow exchange speed in the printing cavity will be faster, resulting in a better cooling effect and a faster cooling rate. The heat insulation cavity can reduce heat exchange between the inside and outside of the housing due to large temperature differences, avoiding unnecessary temperature loss and further improving the cooling or heating rate.

[0016] Furthermore, a filter screen is installed at the second connection port. The filter screen can filter dust and impurities carried by the airflow, preventing the airflow from polluting the working environment of the printing chamber.

[0017] Compared with existing technologies, the beneficial effects are: 1. The temperature control system of this invention comprises a semiconductor cooling chip, a coolant circulation assembly, a refrigerant circulation assembly, and a heat sink, forming a three-stage cooling design. By utilizing two circulation systems, the cooling effect of the semiconductor cooling chip is ultimately improved, resulting in a wider temperature control range and broader applicability of the 3D printing temperature control system, thus meeting the needs of printing complex biomaterials and manufacturing organ-on-a-chip. Specifically, the refrigerant circulation assembly cools the circulating coolant in the coolant circulation assembly, and the cooled coolant then cools the heat sink, accelerating heat dissipation from the hot end of the semiconductor cooling chip, improving its cooling effect, and achieving faster cooling and lower temperatures.

[0018] 2. The temperature control system of this invention, when applied to the printing platform or printing chamber, can effectively and rapidly cool down to achieve even lower temperatures. This allows the printing platform or printing chamber to quickly switch temperatures and has a wider temperature control range, meeting the needs of printing complex biomaterials and manufacturing organ-on-a-chip. Furthermore, when the temperature control system of this invention is applied to the printing platform or printing chamber, the main components, such as the heat exchanger, coolant tank, pump, and refrigerant circulation components, are located outside the printing chamber. This avoids the problems of complex structure, excessive size, and limited cooling effect caused by integrating the temperature control system into the printing platform or printing chamber. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of a temperature control system for 3D printing. Figure 2 This is a schematic diagram of the radiator structure; Figure 3 This is a schematic diagram of the reflux pipe structure; Figure 4 This is a structural diagram of a printing platform; Figure 5 This is a schematic diagram of a printed chamber. Figure 6 yes Figure 5 A front view of the box body of the printed compartment; Figure 7 yes Figure 6 A sectional view of the printed compartment in the AA direction; Figure 8 This is a schematic diagram of the internal structure of the airflow cavity inside the printing chamber; Figure 9 This is a structural schematic diagram of the partition components inside the printed cabin.

[0020] Among them, 100-semiconductor cooling chip; 200-coolant circulation assembly; 210-heat exchanger; 220-coolant tank; 221-return pipe; 222-heat dissipation fins; 230-pump body; 300-heat sink; 310-coolant flow channel; 400-temperature control unit; 500-refrigerant circulation assembly; 510-compressor; 520-radiator; 521-heat dissipation unit; 5211-heat dissipation fins; 522-heat dissipation pipes; 5 23-First fan blade; 524-Second fan blade; 600-Platform receiving plate; 610-Heat insulation plate; 700-Box body; 710-Printing chamber; 720-Airflow chamber; 721-Through hole; 722-Separator; 7221-Melting liquid port; 7222-Hot air outlet; 730-Flow chamber; 731-First connecting port; 732-Second connecting port; 733-Filter screen; 740-Insulation chamber; 800-Heat exchanger; 900-Fan. Detailed Implementation

[0021] The accompanying drawings are for illustrative purposes only and should not be construed as limiting this patent. To better illustrate this embodiment, some components in the drawings may be omitted, enlarged, or reduced, and do not represent the actual dimensions of the product. It is understandable to those skilled in the art that some well-known structures and their descriptions may be omitted in the drawings. The positional relationships described in the drawings are for illustrative purposes only and should not be construed as limiting this patent.

[0022] In the accompanying drawings of the embodiments of the present invention, the same or similar reference numerals correspond to the same or similar components. In the description of the present invention, it should be understood that if terms such as "upper," "lower," "left," "right," "long," and "short" indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings, they are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, the terms used to describe positional relationships in the drawings are only for illustrative purposes and should not be construed as limiting the present patent. For those skilled in the art, the specific meaning of the above terms can be understood according to the specific circumstances.

[0023] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of this invention, "a plurality of" means two or more, unless otherwise explicitly specified.

[0024] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0025] The technical solution of the present invention will be further described in detail below through specific embodiments and in conjunction with the accompanying drawings: Example 1 like Figure 1 The illustration shows an embodiment of a temperature control system for 3D printing, including a thermoelectric cooler 100, a coolant circulation assembly 200, a refrigerant circulation assembly 500, a heat sink 300 attached to one end of the thermoelectric cooler 100, and a temperature control unit 400 electrically connected to the thermoelectric cooler 100. The heat sink 300 has a coolant flow channel 310, and the coolant circulation assembly 200 supplies coolant to the heat sink 300. The coolant circulation assembly 200 includes a heat exchanger 210 for exchanging heat with the coolant, and the refrigerant circulation assembly 500 is connected to the heat exchanger 210 to supply refrigerant to the heat exchanger 210 and cool the coolant flowing through the heat exchanger 210.

[0026] Specifically, the coolant circulation assembly 200 also includes a coolant tank 220 and a pump body 230. The outlet of the coolant tank 220 is connected to the pump body 230, the pump body 230 is connected to the inlet of the heat exchanger 210, the outlet of the heat exchanger 210 is connected to the inlet of the coolant channel 310, and the inlet of the coolant tank 220 is connected to the outlet of the coolant channel 310.

[0027] In this embodiment, the refrigerant circulation assembly 500 supplies liquid refrigerant, specifically including a compressor 510 and a radiator 520 connected to the compressor 510. The inlet of the compressor 510 is connected to the refrigerant outlet of the heat exchanger 210, and the outlet of the radiator 520 is connected to the refrigerant inlet of the heat exchanger 210.

[0028] The working principle or workflow of this embodiment is as follows: The temperature control unit 400 controls the thermoelectric cooler 100 to cool or heat by supplying a positive or reverse voltage. Specifically, supplying a positive voltage cools one end of the thermoelectric cooler 100, causing its temperature to drop (this end is the cold end), while the other end, the hot end, experiences a temperature increase. In this embodiment, the heat from the hot end is transferred to the heat sink 300 and carried away by the coolant flowing through the coolant channel 310 within the heat sink 300, thus achieving cooling of the hot end. After the thermoelectric cooler 100 is powered on and stabilized, the temperature difference between the cold and hot ends remains constant. The cooling capacity depends on the temperature of the hot end; therefore, the better the heat dissipation effect of the heat sink 300, the better the cooling capacity of the thermoelectric cooler 100.

[0029] In this embodiment, the pump 230 draws coolant from the coolant tank 220, cools it through the heat exchanger 210, and then flows into the coolant channel 310 to cool the heat sink 300. The coolant then flows back to the coolant tank 220 from the outlet of the coolant channel 310, achieving coolant circulation and cooling. When the coolant passes through the heat exchanger 210, the liquid refrigerant, after being processed by the compressor 510 and radiator 520, enters the heat exchanger 210 through the refrigerant inlet to exchange heat with the coolant, thereby cooling the coolant. The refrigerant after heat exchange then re-enters the compressor 510 from the refrigerant outlet of the heat exchanger 210 for further processing. Through the action of the compressor 510 and radiator 520, a lower-temperature refrigerant is obtained, achieving rapid cooling of the coolant, thereby improving the heat dissipation effect of the heat sink 300 and ultimately enhancing the cooling effect of the thermoelectric cooler 100.

[0030] When heating is required, the coolant circulation assembly 200 and the refrigerant circulation assembly 500 are stopped. The temperature control unit 400 simply inputs a reverse voltage to the thermoelectric cooler 100, causing the hot and cold ends of the thermoelectric cooler 100 to be switched. Since no coolant participates in the circulation and heat dissipation, the temperature will rise to achieve the purpose of heating.

[0031] The beneficial effects of this embodiment are as follows: By setting up a semiconductor cooling chip 100, a heat sink 300, a coolant circulation assembly 200, and a refrigerant circulation assembly 500, a three-stage cooling design is formed, which includes two sets of circulation systems. This can accelerate the heat dissipation of the hot end of the semiconductor cooling chip. By changing the energizing sequence of the semiconductor cooling chip 100, its cold and hot ends can be interchanged to achieve cooling or heating. During the cooling process, the refrigerant circulates in the compressor 510, the radiator 520, and the heat exchanger 210; the coolant circulates in the coolant tank 220, the pump body 230, the heat exchanger 210, and the heat sink 300. After the refrigerant is cooled by the compressor 510 and radiator 520 in the refrigerant circulation assembly 500, it is then cooled by heat exchange in the heat exchanger 210, which accelerates the cooling speed of the coolant. The cooled coolant then cools the heat sink 300, which can accelerate the heat dissipation of the hot end of the thermoelectric cooler 100 and improve the cooling effect of the cold end of the thermoelectric cooler 100, achieving the purpose of faster cooling and lower temperature. It can quickly realize the transition from high temperature to low temperature, and has a wider temperature control range and a wider range of applications.

[0032] In this embodiment, the heat sink 300 is a liquid-cooled copper block. The heat exchanger 210 is a tubular heat exchanger.

[0033] Example 2 A second embodiment of a temperature control system for 3D printing, based on embodiment 1, differs from embodiment 1 in that the radiator 520 and the coolant circulation assembly 200 are further defined.

[0034] The radiator 520 includes a plurality of heat dissipation units 521, heat dissipation pipes 522 surrounding the heat dissipation units 521, and a fan. Each heat dissipation unit 521 is formed by a plurality of heat dissipation fins 5211, and the heat dissipation pipes 522 pass through all the heat dissipation fins 5211 and form a multi-layer structure by surrounding the heat dissipation fins 5211 in the radial and axial directions; there are at least two heat dissipation units 521 arranged in the radial direction, and the heat dissipation fins 5211 of two adjacent heat dissipation units 521 are arranged alternately; the inlet and outlet of the heat dissipation pipes 522 are the inlet and outlet of the radiator 520, respectively. The fan includes a first blade 523, a second blade 524, and a motor that drives the first blade 523 and the second blade 524 to rotate. The first blade 523 is located in the inner cavity formed by the heat dissipation unit 521 and extends in the axial direction. The second blade 524 is located at one end of the heat dissipation unit 521 and extends in the radial direction. The radial projections of the heat sinks 5211 are all within the coverage area of ​​the first blade 523. The axial projections of the heat sinks 5211 are all within the coverage area of ​​the second blade 524. The heat dissipation unit 521, formed by multiple heat sinks 5211, forms an inner cavity at the center. The first blade 523 is located inside the inner cavity. When the motor drives the first blade 523 to rotate, it can draw in heat from the area around the heat sink 5211, thereby cooling the heat sink 5211. At the same time, the second blade 524 discharges the air drawn in by the first blade 523 from one end, realizing the circulation of the cooling airflow. When the first fan blade 523 is working, air enters or exits through each air duct formed between adjacent heat sinks 5211, thus fully utilizing the heat dissipation function of each heat sink 5211 and improving the heat dissipation effect of the radiator 520. In this embodiment, the axial direction refers to the axial direction of the annulus formed by the heat dissipation unit 521, and the radial direction refers to the radial direction of the annulus formed by the heat dissipation unit 521.

[0035] The inlet of the coolant tank 220 and the outlet of the coolant flow channel 310 are connected by a return pipe 221. The return pipe 221 is made of metal, specifically copper or a copper alloy in this embodiment. The return pipe 221 has at least one straight section, on which heat dissipation fins 222 are arranged circumferentially along the circumference of the return pipe 221. Part of the heat dissipation fins 222 are located inside the circumferential tube, and part is located outside. When the coolant flows through this straight section, the heat dissipation fins 222 divide the coolant, allowing the coolant to exchange heat with the outside environment through the fins 222 with a large heat exchange area. This results in a lower temperature of the coolant returning to the coolant tank 220, which is more conducive to subsequent cooling and ultimately improves the heat dissipation effect on the heat sink 300.

[0036] Example 3 like Figure 4The illustration shows an embodiment of a printing platform, including a platform receiving plate 600, a heat insulation plate 610, and a temperature control system as described in Embodiment 1 or 2. A thermoelectric cooler 100 and a heat sink 300 are located between the platform receiving plate 600 and the heat insulation plate 610, with the other end of the thermoelectric cooler 100 in close contact with the bottom surface of the platform receiving plate 600. The heat exchanger 210, coolant tank 220, pump 230, compressor 510, and heat sink 520 are all located outside the printing chamber, avoiding the problems of complex structure, excessive size, and limited cooling effect caused by integrating the temperature control system into the printing platform or printing chamber.

[0037] The beneficial effects of this embodiment are as follows: When cooling the platform receiving plate 600, the end of the thermoelectric cooler 100 that is in close contact with the bottom surface of the platform receiving plate 600 is the cold end. The thermoelectric cooler 100 directly controls the temperature of the platform receiving plate 600, which can reduce the temperature of the platform receiving plate 600 to near the temperature of the cold end. The end of the thermoelectric cooler 100 that is connected to the first heat sink 300 is the hot end, and the cooling capacity of the cold end is improved by the cooling method described in Embodiment 1 or 2. Therefore, the platform receiving plate 600 can achieve a lower temperature more quickly. Using the temperature control system of Embodiment 1 or 2, the minimum temperature of the platform receiving plate surface can be reduced to -25°C, and the maximum temperature can be increased to 180°C. Therefore, the temperature control range of the printing platform in this embodiment is from -25°C to 180°C, which can meet the needs of printing complex biomaterials and manufacturing organ-on-a-chip.

[0038] The working principle of the temperature control system in this embodiment is the same as that in Embodiment 1.

[0039] Example 4 like Figure 5-7 The illustration shows an embodiment of a printing chamber, including a housing 700 and a temperature control system of embodiment 1 or 2; a semiconductor cooling chip 100 is installed inside the housing 700 and is used to control the temperature inside the housing 700.

[0040] like Figure 5 As shown, the heat exchanger 210, coolant tank 220, pump body 230, compressor 510 and radiator 520 are all located outside the housing 700, avoiding the problems of complex structure, excessive size and limited cooling effect caused by integrating the temperature control system into the printing chamber.

[0041] In this embodiment, as Figure 7As shown, the housing 700 is at least divided into a printing chamber 710, an airflow chamber 720, and a flow chamber 730. The airflow chamber 720 is located on one side of the printing chamber 710, and the flow chamber 730 is located above the printing chamber 710. The airflow chamber 720 is provided with a through hole 721 communicating with the printing chamber 710. The through hole 721 is located at the bottom of the printing chamber 710. The flow chamber 730 communicates with the airflow chamber 720 and the printing chamber 710 through a first connecting port 731 and a second connecting port 732, respectively. The semiconductor refrigeration chip 100, the heat exchanger 800, and the fan 900 are all installed in the airflow cavity 720. The heat exchanger 800 is in close contact with the other end of the semiconductor refrigeration chip 100. An air duct is provided inside the heat exchanger 800. The heat exchanger 800 is located between the air outlet of the fan 900 and the first connecting port 731. There is a gap between the air outlet of the fan 900 and the heat exchanger 800 and it faces the entrance of the air duct. The air inlet of the fan 900 is connected to the through hole 721.

[0042] The housing 700 is divided into multiple cavities according to different functions. Under the action of the fan 900, the airflow can form a fixed flow path, which can more efficiently cool or heat up the printing cavity 710. At the same time, the printing cavity 710 and the airflow cavity 720 are separated to prevent the heat generated by the semiconductor cooling chip 100 from affecting the printing cavity 710. The flow cavity 730 is arranged above the printing cavity 710, and the through hole 721 is arranged below the printing cavity 710. The air inlet of the fan 900 can draw in the airflow, so that the airflow can exchange heat with the air in the printing cavity 710 more quickly or fill the printing cavity 710, so as to achieve the purpose of rapid temperature change of the printing cavity 710. Moreover, the airflow drawn in by the fan 900 is the airflow in the printing cavity 710. After being cooled or heated, this part of the airflow is lower or higher than the temperature of the outside air, which can also accelerate the cooling or heating of the airflow by the heat exchanger 800. Using this internal circulation method, the temperature rise and fall of the printing cavity 710 can be more rapid.

[0043] At least one side of the housing 700 is provided with a heat insulation cavity 740. The heat insulation cavity 740 can reduce heat exchange between the flow cavity 730 and the printing cavity 710 and the outside environment, avoid unnecessary temperature loss, and further improve the cooling or heating rate. In this embodiment, the airflow cavity 720 is disposed on the back of the printing cavity 710, and the heat insulation cavity 740 is located at the bottom of the printing cavity 710, on both sides of the printing cavity 710, and above the flow cavity 730. In other embodiments, the heat insulation cavity 740 may also be disposed only above the flow cavity 730. The heat insulation cavity 740 can be formed by adding a partition inside the housing 700 to separate the multiple cavities to form the printing cavity 710, the airflow cavity 720, the flow cavity 730, and multiple heat insulation cavities 740. An outer frame can also be added to the outside of the housing 700, and a heat insulation cavity 740 is formed by the gap between the outer frame and the housing 700. The outer frame can be connected to the outer surface of the housing 700 only partially to form a large area heat insulation cavity 740. In order to avoid affecting the heat dissipation of the hot end of the thermoelectric cooler 100, the outer frame does not cover the surface on the side where the airflow cavity 720 is provided. In addition to being dissipated by the heat sink 300, the hot end of the thermoelectric cooler 100 can also be dissipated by directly exchanging heat with the outside air.

[0044] The working principle of this embodiment is as follows: When cooling the inside of the box 700, the temperature control unit sends a positive voltage to cool the cold end of the semiconductor cooling chip 100. The low temperature is transferred to the heat exchanger 800. The end of the semiconductor cooling chip 100 connected to the first heat sink 300 is the hot end and is cooled by the method described in embodiment 1 or 2, so that the cooling capacity of the cold end is improved. There is a gap between the air outlet of the fan 900 and the heat exchanger 800. The airflow blown out of the air outlet of the fan 900 is diffused and covers the heat exchanger 800. The heat exchanger 800 is in close contact with the cold end of the semiconductor cooling chip 100. The airflow flowing through the air duct of the heat exchanger 800 is rapidly cooled to form a cold airflow. The cold airflow enters the flow chamber 730 from the first connecting port 731 and then enters the printing chamber 710 from the second connecting port 732. Since the density of the cold airflow is greater than that of the room air with a higher temperature, the cold airflow will move downward. Under the suction effect generated by the air inlet of the fan 900, it can quickly cover the printing chamber 710 from top to bottom, so that the temperature of the printing chamber 710 is rapidly reduced. When heating the inside of the chamber 700, the coolant circulation assembly 200 and the refrigerant circulation assembly 500 are stopped. Only a reverse voltage needs to be supplied to heat one end of the semiconductor cooling chip 100 that is attached to the heat exchanger 800, while cooling the other end. The airflow flowing through the air duct inside the heat exchanger 800 is rapidly heated to form a hot airflow, which is then driven by the fan 900 to circulate in the printing chamber, thereby achieving rapid heating inside the chamber 700.

[0045] The beneficial effects of this embodiment are as follows: The semiconductor cooling chip 100 is used to cool or heat the air inside the housing 700. Airflow is generated by the fan 900 and forms a fixed flow path within the three cavities, rapidly exchanging heat with the air inside the housing 700 to achieve rapid cooling and heating, allowing for rapid temperature switching within the housing 700. Furthermore, based on the temperature control system of Embodiment 1, during cooling, the coolant temperature, after heat exchange with the refrigerant circulation component 500, can reach a minimum temperature of zero degrees Celsius. The coolant cools the hot end of the semiconductor cooling chip 100, allowing the cold end of the semiconductor cooling chip to reach below zero degrees Celsius. This, in turn, allows the temperature of the heat exchanger 800, which is in close contact with the cold end of the semiconductor cooling chip 100, to reach below zero degrees Celsius. The cold airflow cooled by the heat exchanger 800 can reach or approach zero degrees Celsius. Therefore, after the cold airflow cools the inside of the housing 700 for a period of time, the temperature inside the housing 700 can reach or approach zero degrees Celsius. During heating, one end of the heat exchanger 800 is heated while the other end is cooled. Air at the heated end is circulated by a fan 900. Since no coolant is involved in the circulation for heat dissipation, the overall temperature of the molding chamber can rise to 80°C. Therefore, the temperature control range of the printing chamber in this embodiment is from 0°C to 80°C, which can meet the needs of printing complex biomaterials and manufacturing organ-on-a-chip.

[0046] In some other embodiments, a filter 733 is installed at the second connection port 732. Under the action of the fan 900, the airflow entering the flow chamber 730 enters the printing chamber 710 through the second connection port 732 and is filtered by the filter 733. The filter 733 can filter dust and impurities carried by the airflow to ensure that the environment of the printing chamber 710 is not contaminated.

[0047] In some other implementations, such as Figure 8 As shown, the airflow cavity 720 is provided with a partition 722, which has a fan connection port, a semiconductor mounting port and an airflow outlet. The heat exchanger 800 is installed inside the partition 722, with one end face of the heat exchanger 800 fitting against the partition 722. The semiconductor mounting port is located on one end face of the partition 722. The fan 900 is installed at the fan connection port and the air outlet of the fan 900 faces the interior of the partition 722. The semiconductor cooling chip 100 is installed at the semiconductor mounting port. The airflow outlet is connected to the first communication port 731.

[0048] In other embodiments, such as the printing chamber temperature control range of Embodiment 3, which is between 0°C and 80°C and is difficult to lower than 0°C, this is because below 0°C, the heat exchanger 800 will gradually frost over upon contact with air, affecting the cooling of the air. In view of this situation, such as... Figure 8-9As shown, the heat exchanger 800 is tilted, and the angle between the air duct of the heat exchanger 800 and the horizontal plane is an acute angle. A first opening and closing mechanism for controlling the first connecting port 731 is provided at the first connecting port 731, and a heating mechanism is provided at the air outlet of the fan 900. A melting liquid port 7221 is provided at the lower end of the bottom surface of the partition 722, and a hot air outlet 7222 is provided at the top of the partition 722. A second opening and closing mechanism is provided at the hot air outlet 7222. Since the melting liquid port 7221 is located on the bottom surface of the partition 722 and is opposite to the airflow direction of the fan 900, when the first connecting port 731 is in the open state, the cold air will not be blown out from the melting liquid port. When the heat exchanger 800 frosts over, the first connecting port 731 is closed by the first opening and closing mechanism, and the hot air outlet 7222 is opened by the second opening and closing mechanism, activating the heating mechanism. The heating mechanism can be a heating wire. The air blown by the fan 900 is heated by the heating wire, causing the frost on the surface of the heat exchanger 800 to melt or sublimate into gas. The gas is blown out from the hot air outlet along with the hot air. Due to the inclined arrangement of the heat exchanger 800, the melted water flows towards the lowest point and then flows out from the melt outlet 7221. The airflow cavity 720 is provided with an outlet for connecting to the outside. The outlet can be located at the bottom, and the hot air and melted water flow out from the outlet of the airflow cavity 720. In addition, to reduce the loss of cold airflow in the printing cavity 710, another fan can be set up specifically for defrosting. If two fans are set up, the fans are arranged side by side, and the air inlet of the fan used for defrosting is connected to the airflow cavity 720 or the outside. The first opening and closing mechanism can be a louvered door curtain, an electric door curtain, an automatic roller blind, or an electric sliding door panel; the second opening and closing mechanism can be an electric airtight valve, a louvered damper, or a self-weight damper.

[0049] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art can make other variations or modifications based on the above description. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A temperature control system for 3D printing, characterized in that, The device includes a thermoelectric cooler (100), a coolant circulation assembly (200), a refrigerant circulation assembly (500), a heat sink (300) attached to one end of the thermoelectric cooler (100), and a temperature control unit (400) electrically connected to the thermoelectric cooler (100). The heat sink (300) has a coolant flow channel (310). The coolant circulation assembly (200) supplies coolant to the heat sink (300), and the refrigerant circulation assembly (500) cools the coolant in the coolant circulation assembly (200).

2. The temperature control system for 3D printing according to claim 1, characterized in that, The coolant circulation assembly (200) includes a heat exchanger (210) for exchanging heat with the coolant, and the refrigerant circulation assembly (500) includes a compressor (510) and a radiator (520) connected to the compressor (510). The inlet of the compressor (510) is connected to the refrigerant outlet of the heat exchanger (210), and the refrigerant outlet of the radiator (520) is connected to the refrigerant inlet of the heat exchanger (210).

3. A temperature control system for 3D printing according to claim 2, characterized in that, The radiator (520) includes several heat dissipation units (521), heat dissipation pipes (522) surrounding the heat dissipation units (521), and a fan; the heat dissipation unit (521) is formed by multiple heat dissipation fins (5211), and the heat dissipation pipes (522) pass through all the heat dissipation fins (5211) and form a multi-layer structure in the radial and axial directions of the heat dissipation fins (5211); the heat dissipation unit (521) has at least two, and the heat dissipation fins (5211) of two adjacent heat dissipation units (521) are arranged alternately; the inlet and outlet of the heat dissipation pipes (522) are the inlet and outlet of the radiator (520), respectively.

4. A temperature control system for 3D printing according to claim 3, characterized in that, The fan includes a first blade (523), a second blade (524), and a motor that drives the first blade (523) and the second blade (524) to rotate; the first blade (523) is located in the inner cavity formed by the heat dissipation unit (521) and extends in the axial direction; the second blade (524) is located at one end of the heat dissipation unit (521) and extends in the radial direction; the radial projection of the heat sink (5211) is located within the coverage area of ​​the first blade (523); the axial projection of the heat sink (5211) is located within the coverage area of ​​the second blade (524).

5. A temperature control system for 3D printing according to claim 2, characterized in that, The coolant circulation assembly (200) further includes a coolant tank (220) and a pump body (230). The outlet of the coolant tank (220) is connected to the pump body (230), the pump body (230) is connected to the inlet of the heat exchanger (210), the outlet of the heat exchanger (210) is connected to the inlet of the coolant channel (310), and the inlet of the coolant tank (220) is connected to the outlet of the coolant channel (310).

6. A printing platform, characterized in that, The device includes a platform receiving plate (600), a heat insulation plate (610), and a temperature control system according to any one of claims 1-5, wherein the semiconductor cooling chip (100) and the heat sink (300) are located between the platform receiving plate (600) and the heat insulation plate (610), and the other end of the semiconductor cooling chip (100) is in close contact with the bottom surface of the platform receiving plate (600).

7. A printing chamber, characterized in that, Includes a housing (700) and a temperature control system as described in any one of claims 1-5; the semiconductor cooling chip (100) is installed inside the housing (700) and is used to control the temperature inside the housing (700).

8. A printing chamber according to claim 7, characterized in that, The housing (700) is at least divided into a printing chamber (710), an airflow chamber (720), and a flow chamber (730). The airflow chamber (720) is connected to the printing chamber (710) through a through hole (721). The flow chamber (730) is connected to the airflow chamber (720) and the printing chamber (710) through a first connecting port (731) and a second connecting port (732), respectively. The semiconductor cooling chip (100) is installed in the airflow chamber (720), and a fan (900) is provided in the airflow chamber (720).

9. A printing chamber according to claim 8, characterized in that, The airflow cavity (720) is also provided with a heat exchanger (800) that is in close contact with the other end of the semiconductor cooling chip (100). The heat exchanger (800) is provided with an air duct. The heat exchanger (800) is located between the air outlet of the fan (900) and the first connecting port (731). There is a gap between the air outlet of the fan (900) and the heat exchanger (800) and it faces the entrance of the air duct. The air inlet of the fan (900) is connected to the through hole (721).

10. A printing chamber according to claim 9, characterized in that, The airflow cavity (720) is located on one side of the printing cavity (710), the flow cavity (730) is located above the printing cavity (710), and at least one side of the housing (700) is provided with a heat insulation cavity (740).

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