An ultra-high precision constant temperature tank

Abstract

The application relates to an ultrahigh-precision constant-temperature tank, which comprises a box body, a tank body, a control system and a refrigeration system, the tank body is installed on one side of the inside of the box body, a stirring device is installed on one side of the inside of the tank body, and a heating plate is installed on the outside of the tank body; the refrigeration system is installed on the other side of the inside of the box body, the control system is installed on the top of the refrigeration system and controls the start-stop operation of components in the refrigeration system, an evaporator is arranged in the refrigeration system, and the evaporator is installed on the outside of the heating plate. The ultrahigh-precision constant-temperature tank provided by the application realizes high-precision temperature control by adopting a precision-controlled hot gas bypass loop and a condenser and an evaporator for precise heat transfer, and precisely controlling the evaporation amount.

Description

Technical Field

[0001] This invention relates to the field of refrigeration technology, and in particular to an ultra-high precision constant temperature bath. Background Technology

[0002] Thermostatic baths are particularly suitable for chemical, biological, and physical laboratories that require maintaining low or normal temperature conditions, and are an essential piece of equipment in laboratories. Thermostatic baths can be combined with rotary evaporators, vacuum freeze dryers, circulating water vacuum pumps, magnetic stirrers, and other instruments to perform multifunctional chemical reactions and drug storage.

[0003] Thermostatic baths require precise temperature control of the liquid inside, with current achievable accuracy being 0.1℃ or even 0.01℃. However, achieving even higher precision temperature control is currently difficult, hindering scientific research. To further refine this precision, an ultra-high-precision thermostatic bath is proposed. Summary of the Invention

[0004] The purpose of this invention is to provide an ultra-high precision constant temperature bath to solve the problems encountered in the background art.

[0005] To achieve the above objectives, the technical solution of the present invention is as follows:

[0006] An ultra-high precision constant temperature bath includes a box, a tank, a control system, and a refrigeration system. The tank is installed inside one side of the box, and a stirring device is installed inside the tank. A heating plate is installed outside the tank. The refrigeration system is installed inside the other side of the box. The control system is installed on top of the refrigeration system and controls the start and stop operation of the components in the refrigeration system. The refrigeration system is equipped with an evaporator, which is installed outside the heating plate.

[0007] In the above scheme, the refrigeration system includes a compressor, an expansion valve, an evaporator, a dryer flask, a condenser, a regenerator, a needle valve, a first cooling capacity adjustment knob, and a second cooling capacity adjustment knob. The compressor is installed at the bottom of the inner cavity of the housing and is connected to the regenerator. The top of the dryer flask is connected to the expansion valve. One side of the liquid outlet of the expansion valve is connected to the evaporator through a pressure gauge, and the other side is connected to the first cooling capacity adjustment knob through the first needle valve. The hot end of the regenerator is directly connected to the condenser, and the control end of the regenerator is connected to the second cooling capacity adjustment knob through the second needle valve. The cold end in the middle of the regenerator is directly connected to the evaporator.

[0008] In the above scheme, a pressure gauge is also connected to the outside of the expansion valve. The pressure gauge, the first cooling capacity adjustment knob, and the second cooling capacity adjustment knob are installed side by side on the outside of the housing. The expansion valve has a pipeline connected in parallel with it, and the loop formed by this pipeline is the first hot gas bypass loop. The front end of the pipeline is connected to the drying bottle, and the end is connected to the expansion valve outlet pipeline. A first solenoid valve and a first needle valve are provided in the middle of the pipeline. The first needle valve is connected to the outside of the first cooling capacity adjustment knob.

[0009] In another preferred embodiment, the second needle valve and the second solenoid valve form a second hot gas bypass circuit. The inlet of the second hot gas bypass circuit is connected to the cold end of the middle of the regenerator, and the outlet is connected to the air inlet of the compressor. The second needle valve and the second solenoid valve are connected in parallel in the middle of the pipeline, and a second cooling capacity adjustment knob is connected to the outside of the second needle valve.

[0010] In the above scheme, a fan is installed inside the condenser, and both the condenser and the fan are installed at the bottom of the inner cavity of the housing.

[0011] In the above scheme, the stirring device includes a motor and a stirring paddle. The motor is installed on the top of the box, and the drive end of the motor extends into the box and into the tank to be connected to the stirring paddle for transmission. A filter cover is provided on the outer periphery of the stirring paddle, and a cooling fan is installed on the outside of the motor.

[0012] In addition, heating plates are installed on both sides of the tank and superimposed on one side of the evaporator. Simultaneous heating from both sides ensures the uniformity and stability of the temperature field inside the tank. Both the evaporator and condenser have a two-inlet, one-outlet piping structure, with the condenser also having a two-inlet, one-outlet piping configuration to enhance heat exchange efficiency and ensure system stability. The evaporator also has a two-inlet, one-outlet piping configuration and is installed on both sides of the tank. Simultaneous cooling from both sides ensures the uniformity and stability of the temperature field inside the tank.

[0013] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention provides an ultra-high precision constant temperature bath that achieves high-precision temperature control by employing a precisely controlled hot gas bypass circuit and a condenser and evaporator with precise heat transfer, thereby accurately controlling the evaporation rate. The combined chamber, refrigeration system, heating system, stirring device, and control system constitute the entire high-precision constant temperature bath, enabling it to have both large capacity and high precision. In a large-capacity constant temperature bath exceeding 40L, precise temperature control of ±0.0007℃ is achieved, making it suitable for application as a precision instrument in the semiconductor industry. Attached Figure Description

[0014] The disclosure of this invention is illustrated with reference to the accompanying drawings. It should be understood that the drawings are for illustrative purposes only and are not intended to limit the scope of protection of this invention. In the drawings, the same reference numerals are used to refer to the same parts. Wherein:

[0015] Figure 1 This is a schematic diagram of the external structure of the present invention;

[0016] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0017] Figure 3 This is a schematic diagram of the structure of the present invention after the outer shell of the box has been removed;

[0018] Figure 4 for Figure 3 A structural diagram from another perspective;

[0019] Figure 5 This is a schematic diagram of the structure of the tank and the stirring device in this invention;

[0020] Figure 6 This is a schematic diagram of the installation structure of the refrigeration system in this invention;

[0021] Figure 7 for Figure 6 A structural diagram from another perspective;

[0022] Figure 8 This is a schematic diagram of the working principle of the refrigeration system in this invention;

[0023] Figure 9 This is a graph of temperature data measured during the implementation of the present invention.

[0024] Numbering in the diagram: 1-Box body; 11-Heat dissipation mesh; 2-Tank body; 21-Agitator; 22-Motor; 23-Filter cover; 24-Heat dissipation fan; 25-Agitator paddle; 26-Insulation foam board; 3-Control system; 4-Refrigeration system; 40-Compressor; 401-First solenoid valve; 402-Second solenoid valve; 403-Sight glass; 404-First hot gas bypass circuit; 405-Second hot gas bypass circuit; 41-Expansion valve; 42-Evaporator; 43-Drier bottle; 44-Condenser; 45-Regenerator; 46-Fan; 471-First needle valve; 472-Second needle valve; 48-Pressure gauge; 491-First cooling capacity adjustment knob; 492-Second cooling capacity adjustment knob. Detailed Implementation

[0025] To make the technical means, creative features, objectives, and effects of this invention readily understandable, the invention will now be described in further detail with reference to the accompanying drawings. These drawings are simplified schematic diagrams, illustrating only the basic structure of the invention, and therefore only show the relevant components of the invention.

[0026] According to the technical solution of the present invention, without changing the essential spirit of the present invention, those skilled in the art can propose various interchangeable structural methods and implementations. Therefore, the following detailed embodiments and accompanying drawings are merely exemplary descriptions of the technical solution of the present invention, and should not be regarded as the entirety of the present invention or as a limitation or restriction of the technical solution of the present invention.

[0027] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0028] like Figure 1-8 As shown, an ultra-high precision constant temperature bath includes a housing 1, a bath 2, a control system 3, and a refrigeration system 4. The bath 2 is the constant temperature bath itself, installed inside the housing 1 on one side. A thermal insulation foam board 26 is installed at the bottom of the bath 2, and additional thermal insulation foam boards 26 can be installed on its outer perimeter to improve insulation performance. Insulation is achieved by filling the bottom and sides of the bath 2 with thermal insulation foam material or heat-insulating foam material.

[0029] A stirring device 21 is installed on one side of the interior of tank 2. Please refer to [link / reference]. Figure 3 and Figure 5 The stirring device 21 includes a motor 22 and a stirring paddle 25. The motor 22 is mounted on the top of the housing 1, and its drive end extends into the housing 1 and into the tank 2, where it is connected to the stirring paddle 25. The motor 22 drives the stirring paddle 25 to rotate, thereby stirring the liquid in the constant temperature tank. A filter cover 23 with a mesh structure is provided on the outer periphery of the stirring paddle 25. The top of the filter cover 23 is connected to the housing 1 to conduct heat from the liquid to the top of the housing 1. A cooling fan 24 is installed on the outside of the motor 22 to reduce the heat generated during the operation of the motor 22 and to dissipate the heat transferred from the filter cover 23. In addition, during the stirring process, the liquid dissipates heat through stirring, and the mesh filter cover 23 helps to evenly distribute the temperature inside the constant temperature tank, thus maintaining the overall temperature of the constant temperature tank.

[0030] Please see Figure 5 The stirring paddle 25 has a fan blade structure with at least three different angles, which can achieve uniform mixing of the upper and lower layers of fluid in a large-capacity oil tank. In addition, the filter cover 23 has a mesh structure, which also disperses the fluid during the stirring process, making it more uniform.

[0031] Heating plates 5 are installed on both sides of the outside of the tank 2 to maintain a constant temperature. The heating plates 5 control the heating temperature by controlling the heating power. The heating plates 5 will only be turned on when the temperature field needs to be heated or kept constant. The heating plates 5 will not be activated in the simple cooling mode.

[0032] The refrigeration system 4 is installed inside the chamber 1 on the other side. The control system 3 is installed on top of the refrigeration system 4 and controls the start and stop operation of the components in the refrigeration system 4. The refrigeration system 4 has two evaporators 42, each installed on the outside of the heating plate 5 on its respective side, working together to maintain the temperature of the chamber 2. Therefore, in this constant temperature bath equipment, the heating system consists of heating plates 5 arranged side by side with the evaporators 42. The evaporators 42 and the heating plates 5 are stacked together, allowing for a more uniform and stable heat and cold source in the temperature field inside the chamber 2. The overlapping of the two allows for a more balanced heating and cooling, resulting in a more uniform and stable temperature field compared to the traditional separate heating and cooling methods.

[0033] In the above scheme, the refrigeration system 4 includes a compressor 40, an expansion valve 41, an evaporator 42, a dryer 43, a condenser 44, a regenerator 45, a needle valve 47, a first cooling capacity adjustment knob 491, and a second cooling capacity adjustment knob 492. The compressor 40 is installed at the bottom of the inner cavity of the housing 1 and is connected to the regenerator 45. The top of the dryer 43 is connected to the expansion valve 41. One side of the liquid outlet of the expansion valve 41 is connected to the evaporator 42 through a pressure gauge 48, and the other side is connected to the first cooling capacity adjustment knob 491 through the first needle valve 471. The hot end of the side of the regenerator 45 is directly connected to the condenser 44. The control end of the regenerator 45 is connected to the second cooling capacity adjustment knob 492 through the second needle valve 472. The cold end in the middle of the regenerator 45 is directly connected to the evaporator 42.

[0034] Among them, the compressor 40, the regenerator 45, and the expansion valve 41 are all standard components; the condenser 44 is an air-cooled finned tube condenser with a multi-inlet and one-outlet pipe structure, which can more effectively cool the refrigerant flowing through it; the evaporator 42 has a two-inlet and one-outlet pipe structure and is symmetrically distributed on both sides of the shell, which is beneficial to the overall stability and cooling rate.

[0035] A pressure gauge 48 is also connected to the outside of the expansion valve 41. The pressure gauge 48, the first cooling capacity adjustment knob 491, and the second cooling capacity adjustment knob 492 are installed side by side on the outside of the housing 1 for easy viewing or adjustment. The function of the cooling capacity adjustment knob 49 is to adjust the opening of the needle valve 47 to control the refrigerant flow in the hot gas bypass circuit, thereby controlling the refrigerant flow of the entire refrigeration system to achieve precise temperature control.

[0036] As a preferred embodiment, the expansion valve 41 has a parallel pipeline forming a first hot gas bypass circuit 404. The pipeline's front end is connected to a dryer bottle 43, and its end is connected to the outlet pipeline of the expansion valve 41. A first solenoid valve 401 and a first needle valve 471 are located in the middle of the pipeline. A first cooling capacity adjustment knob 491 is connected to the outside of the first needle valve 471. This allows for adjustment of the refrigerant flow rate through the expansion valve 41 pipeline by adjusting the opening degree of the first needle valve 471.

[0037] In addition, the second needle valve 472 and the second solenoid valve 402 form a second hot gas bypass circuit 405. The inlet of the second hot gas bypass circuit 405 is connected to the cold end of the regenerator 45, and the outlet is connected to the air inlet of the compressor 40. The second needle valve 472 and the second solenoid valve 402 are connected in parallel in the middle of the pipeline. The second cooling capacity adjustment knob 492 is connected to the outside of the second needle valve 472. By adjusting the opening of the second needle valve 472, the flow rate of refrigerant entering the compressor 40 can be controlled to achieve precise control of the cooling capacity.

[0038] The hot gas bypass circuit is a circuit in series between the hot gas bypass valve and the solenoid control valve. The first hot gas bypass circuit 404 is the main pipeline circuit, which is connected to the condenser 44 and the evaporator 42 to realize the throttling function of the system. The second hot gas bypass circuit 405 is a parallel circuit to the first hot gas bypass circuit 404, which is used to supplement the first hot gas bypass circuit 404 with refrigerant when the refrigerant flow is insufficient.

[0039] The circuit between condenser 44 and evaporator 42 is: condenser - sight glass - dryer bottle - expansion valve - evaporator. The first hot gas bypass circuit 404 is connected in parallel to the expansion valve 41. Specifically, the inlet of the first hot gas bypass circuit 404 is connected to the dryer bottle 43, and the outlet is at the outlet of the expansion valve 41, with a solenoid valve, needle valve, and knob connected in between. The function of the first hot gas bypass circuit 404 is to replenish or divert refrigerant in the main pipeline when there is an abnormality in the refrigerant flow rate, ensuring that the refrigerant in the main pipeline remains constant, thereby guaranteeing the stability of the cooling capacity within the evaporator.

[0040] A fan 46 is installed inside the condenser 44 to accelerate heat dissipation and conduction. Both the condenser 44 and the fan 46 are installed at the bottom of the inner cavity of the housing 1, opposite the compressor 40.

[0041] A heat dissipation mesh 11 is provided on the side of the housing 1 near the condenser 44 to dissipate the heat in the condenser 44. The drying bottle 43 is connected to the condenser 44 through a sight glass 403. The sight glass 403 can be used to observe whether liquid is generated in the connecting pipe.

[0042] As a preferred embodiment, heating plates 5 are installed on both sides of the tank 2 and superimposed on one side of the evaporator 42. Simultaneous heating from both sides ensures the uniformity and stability of the temperature field inside the tank 2. Both the evaporator 42 and the condenser 44 have a two-inlet, one-outlet piping structure, with the condenser 44 also having a two-inlet, one-outlet piping configuration to enhance heat exchange efficiency and ensure system stability. The evaporator 42 has a two-inlet, one-outlet piping configuration and is installed on both sides of the tank 2. Simultaneous cooling from both sides ensures the uniformity and stability of the temperature field inside the tank 2.

[0043] Please see Figure 9 The X-axis represents the collected data points, and the Y-axis represents the measured temperature range. The data table is generated from approximately 30,000 sets of continuous data points. According to the chart, there are a total of 29,591 continuous data points. During the data acquisition test using this equipment, one data point was collected per second for 8.2 hours, meaning continuous measurement for 8.2 hours. The highest value was 25.00457℃, and the lowest value was 25.00317℃, with a difference of only 0.0014℃. This means the accuracy of this constant temperature bath is ±0.0007℃.

[0044] This invention provides an ultra-high precision thermostatic bath that achieves high-precision temperature control by employing a precisely controlled hot gas bypass circuit and a condenser 44 and evaporator 22 for precise heat transfer, thereby accurately controlling the evaporation rate. The combined chamber 1, refrigeration system 4, heating system, stirring device 21, and control system 3 constitute the entire high-precision thermostatic bath, enabling it to achieve large capacity and high precision. In a large-capacity thermostatic bath exceeding 40L, precise temperature control of ±0.0007℃ is achieved, making it suitable for application as a precision instrument in the semiconductor industry.

[0045] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. These undisclosed elements are all prior art known to those skilled in the art.

[0046] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A high-precision constant temperature bath, characterized in that: The system includes a housing (1), a tank (2), a control system (3), and a refrigeration system (4). The tank (2) is installed on one side inside the housing (1), and a stirring device (21) is installed on one side inside the tank (2). A heating plate (5) is installed on the outside of the tank (2). The refrigeration system (4) is installed on the other side inside the housing (1). The control system (3) is installed on the top of the refrigeration system (4) and controls the start and stop of the components in the refrigeration system (4). An evaporator (42) is provided in the refrigeration system (4), and the evaporator (42) is installed on the outside of the heating plate (5). The refrigeration system (4) includes a compressor (40), an expansion valve (41), an evaporator (42), a dryer flask (43), a condenser (44), a regenerator (45), a needle valve (47), a first cooling capacity adjustment knob (491), and a second cooling capacity adjustment knob (492). The compressor (40) is installed at the bottom of the inner cavity of the housing (1). The compressor (40) is connected to the regenerator (45). The top of the dryer flask (43) is connected to the expansion valve (41). One side of the outlet end of the valve (41) is connected to the pressure gauge (48) through a capillary tube, the other side is connected to the evaporator (42), and the third side is connected to the first cooling capacity adjustment knob (491) through the first needle valve (471); the hot end of the side of the regenerator (45) is directly connected to the condenser (44), the control end of the regenerator (45) is connected to the second cooling capacity adjustment knob (492) through the second needle valve (472), and the cold end in the middle of the regenerator (45) is directly connected to the evaporator (42); The expansion valve (41) has a pipeline connected in parallel with it, and the loop formed by the pipeline is the first hot gas bypass loop (404); the front end of the pipeline is connected to the drying bottle (43), and the end end is connected to the outlet pipeline of the expansion valve (41). The pipeline is equipped with a first solenoid valve (401) and a first needle valve (471) in the middle. The first needle valve (471) is connected to the first cooling capacity adjustment knob (491) on the outside. The second needle valve (472) and the second solenoid valve (402) form a second hot gas bypass circuit (405). The inlet of the second hot gas bypass circuit (405) is connected to the middle cold end of the regenerator (45), and the outlet is connected to the air inlet of the compressor (40). The second needle valve (472) and the second solenoid valve (402) are connected in parallel in the middle of the pipeline. The second cold capacity adjustment knob (492) is connected to the outside of the second needle valve (472). The bottom of the tank (2) is equipped with a heat-insulating foam board (26); the heating plate (5) is installed on two sides of the tank (2) and superimposed on one side of the evaporator (42).

2. The ultra-high precision constant temperature bath according to claim 1, characterized in that: The pressure gauge (48) is connected to the outside of the expansion valve (41), and the pressure gauge (48) is installed side by side with the first cooling capacity adjustment knob (491) and the second cooling capacity adjustment knob (492) on the outside of the housing (1).

3. The ultra-high precision constant temperature bath according to claim 1, characterized in that: A fan (46) is installed inside the condenser (44), and both the condenser (44) and the fan (46) are installed at the bottom of the inner cavity of the housing (1).

4. The ultra-high precision constant temperature bath according to claim 1, characterized in that: The housing (1) is provided with a heat dissipation mesh (11) on the side near the condenser (44), and the bottom of the drying bottle (43) is connected to the outlet of the condenser (44) through a sight glass (403).

5. The ultra-high precision constant temperature bath according to claim 1, characterized in that: The stirring device (21) includes a motor (22) and a stirring paddle (25). The motor (22) is installed on the top of the box (1). The driving end of the motor (22) extends into the box (1) and into the tank (2) to be connected to the stirring paddle (25) in a transmission. A filter cover (23) is provided on the outer periphery of the stirring paddle (25). A cooling fan (24) is installed on the outside of the motor (22).

6. The ultra-high precision constant temperature bath according to claim 1, characterized in that: Both the evaporator (42) and the condenser (44) have a two-inlet-one-outlet piping structure.

Images