阅读说明：本技术 一种多点控温低温大面源黑体 (Multi-point temperature control low-temperature large surface source black body ) 是由 杨文� 刘石神 张腾飞 吕慧峰 陶毅 于 2021-09-15 设计创作，主要内容包括：本发明公开了一种多点控温低温大面源黑体,由黑体模块和温控模块两个分体式模块组成,所述黑体模块包括第一壳体以及依次设于第一壳体内的黑体板、半导体制冷器和散热组件,所述温控模块包括第二壳体,所述第二壳体内固定安装有温控组件和电源模块,所述黑体板内设有多个测温点,每个所述测温点均设有与温控组件电连接的温度传感器,所述温控组件和黑体模块均与电源模块电连接,所述温控组件适于依据PID参数进行计算来调节所述半导体制冷器的功率。本发明提高了低温大面源黑体的温度均匀性和稳定性,缩短稳定时间,进而提高系统安全性。(The invention discloses a multi-point temperature control low-temperature large-area source black body which comprises a black body module and a temperature control module, wherein the black body module comprises a first shell, a black body plate, a semiconductor refrigerator and a heat dissipation assembly, the black body plate, the semiconductor refrigerator and the heat dissipation assembly are sequentially arranged in the first shell, the temperature control module comprises a second shell, the temperature control assembly and a power supply module are fixedly arranged in the second shell, a plurality of temperature measuring points are arranged in the black body plate, each temperature measuring point is provided with a temperature sensor electrically connected with the temperature control assembly, the temperature control assembly and the black body module are electrically connected with the power supply module, and the temperature control assembly is suitable for calculating according to PID parameters to adjust the power of the semiconductor refrigerator. The invention improves the temperature uniformity and stability of the low-temperature large-area source black body, shortens the stabilization time and further improves the system safety.)

1. A multipoint temperature control low-temperature large surface source black body is characterized in that: the temperature control module comprises a black body module and two split modules of the temperature control module, wherein the black body module comprises a first shell (1) and a black body plate (2), a semiconductor refrigerator (3) and a heat dissipation assembly (4) which are sequentially arranged in the first shell (1), the temperature control module comprises a second shell (5), a temperature control assembly (6) and a power module (7) are fixedly arranged in the second shell (5), a plurality of temperature measuring points are arranged in the black body plate (2), each temperature measuring point is provided with a temperature sensor (8) which is electrically connected with the temperature control assembly (6), the temperature control assembly (6) and the black body module are electrically connected with the power module (7), and the temperature control assembly (6) is suitable for calculating according to PID parameters to adjust the power of the semiconductor refrigerator (3).

2. The multi-point temperature control low-temperature large surface source blackbody according to claim 1, wherein: the black plate (2) is divided into four unit areas which are uniformly distributed, namely an upper left unit area, an upper right unit area, a lower left unit area and a lower right unit area, and each unit area is provided with a temperature measuring point.

3. The multi-point temperature control low-temperature large surface source blackbody according to claim 2, wherein: the semiconductor refrigerator (3) is provided with four unit areas which are respectively and correspondingly arranged at the rear ends of the four unit areas of the black plate (2), the temperature control assembly (6) adopts multipoint partition independent temperature control and comprises four temperature controllers (6-1), and each temperature controller (6-1) is respectively and electrically connected with the corresponding semiconductor refrigerator (3) and is independently controlled.

4. The multi-point temperature control low-temperature large surface source blackbody according to claim 3, wherein: the temperature controller (6-1) is a digital display temperature controller and controls the semiconductor refrigerator (3) by adopting a direct current voltage mode.

5. The multi-point temperature control low-temperature large surface source blackbody according to claim 3, wherein: the touch screen (6-2) is fixedly installed on the second shell (5), and the touch screen (6-2) is electrically connected with the temperature controller (6-1) and is suitable for controlling the temperature of the temperature controller (6-1).

6. The multi-point temperature control low-temperature large surface source blackbody according to claim 1, wherein: be equipped with communication serial ports (9) in second casing (5), be equipped with first electric connector (1-1) on first casing (1), be equipped with second electric connector (5-1) of being connected with communication serial ports (9) electricity on second casing (5), the temperature control module realizes being connected with the electricity of black body module through connecting first electric connector (1-1) and second electric connector (5-1).

7. The multi-point temperature control low-temperature large surface source blackbody according to claim 1, wherein: the heat dissipation assembly (4) comprises a transition plate (4-1), a heat dissipation fin assembly (4-2) and a heat dissipation fin cover plate (4-3) which are fixedly installed at the rear end of the semiconductor refrigerator (3) in sequence, a heat dissipation fan (4-4) is fixedly installed above the heat dissipation fin assembly (4-2), an air outlet (1-2) which is opposite to the heat dissipation fan (4-4) is formed in the top of the first shell (1), and a heat dissipation fan protection cover (4-5) which is fixedly installed on the first shell (1) is arranged at the air outlet (1-2); the rear side of the first shell (1) is provided with a heat dissipation groove (1-3), and the heat dissipation fin assembly (4-2) and the heat dissipation fin cover plate (4-3) extend to the heat dissipation groove (1-3).

8. The multi-point temperature control low-temperature large surface source blackbody according to claim 1, wherein: be equipped with thermal-insulated subassembly (10) between black body board (2) and semiconductor cooler (3) and first casing (1), thermal-insulated subassembly (10) is including parcel heat preservation (10-1) on the outer peripheral face of black body board (2) and semiconductor cooler (3), locates heat insulating board (10-2) between the front end of black body board (2) and first casing (1) to and connect black body board (2) and heat-radiating component (4) heat insulation post (10-3).

9. The multi-point temperature control low-temperature large surface source blackbody according to claim 1, wherein: the front end of blackboard board (2) is equipped with prevents frosting subassembly (11), prevent frosting subassembly (11) including preceding after to in proper order fixed mounting on first casing (1) and be located protection front shroud (11-1) and gas curtain (11-2) of blackboard board (2) front end, movable mounting has window baffle (11-3) on protection front shroud (11-1), be equipped with gas inlet on gas curtain (11-2), outside gas passes through gas inlet gets into gas curtain (11-2) and forms the gas curtain.

10. The multi-point temperature control low-temperature large surface source blackbody according to claim 9, wherein: the air curtain (11-2) comprises a frame (11-2-1) and a cavity which is arranged in the frame (11-2-1) and is connected with the air inlet, and the inner wall of the frame (11-2-1) is provided with a plurality of small holes (11-2-2) communicated with the cavity.

Technical Field

The invention relates to the technical field of optical characteristics, in particular to a multi-point temperature control low-temperature large surface source black body.

Background

A black body is an ideal object with emissivity and absorptivity of 1, i.e. it can absorb all wavelengths of radiation at any temperature and emit radiation to the maximum. In reality there is no ideal black body, but a device black body manufactured on the same principle can be used to approximately replace the black body.

The black body of the equipment has the main function of generating standard radiation at a certain temperature, and is mainly used for calibrating various radiation thermometers in temperature measurement, such as an optical pyrometer, an infrared thermometer, an infrared thermal imager and the like. With the development of scientific technology, the application of the equipment black body is not limited to the application in the aspect of temperature measurement, and in the aspect of optics, the equipment black body is generally adopted as a standard radiation source and a standard background light source. In optical applications, with the development of infrared technology in recent years, the application of a surface source black body is more and more extensive, and the development of the surface source black body is started to the low-temperature field, for example, an infrared focal plane array detector, an infrared imaging system, an infrared radiation temperature measurement system and the like all need various large-area low-temperature black body radiation sources.

At present, the low-temperature large-area source black body generally adopts single-point temperature control, namely a temperature control point, a temperature controller and a power element, the control mode is that heat is transmitted and radiated from the middle to the periphery, which inevitably results in the results of middle heat and periphery cooling, the higher the temperature deviation is, in addition, the higher the temperature is, the higher the surface temperature of the large-area source black body is due to the influence of air hot air flow from bottom to top, therefore, the temperature of the middle-upper position of the large-area source black body is higher than that of the middle-lower position, the temperature gradient causes the uneven distribution of the surface temperature of the existing large-area source black body, meanwhile, the single-point temperature control current is large, the system overshoot is large, the stabilization time is slow, and the system safety is not high.

Disclosure of Invention

The invention aims to provide a multi-point temperature control low-temperature large-area source black body aiming at the defects of the prior art, so that the temperature uniformity and stability of the low-temperature large-area source black body are improved, the stabilization time is shortened, and the system safety is improved.

The technical scheme for realizing the aim of the invention is as follows:

a multi-point temperature control low-temperature large-area source black body comprises a black body module and a temperature control module, wherein the black body module comprises a first shell, a black body plate, a semiconductor refrigerator and a heat dissipation assembly, the black body plate, the semiconductor refrigerator and the heat dissipation assembly are sequentially arranged in the first shell, the temperature control module comprises a second shell, a temperature control assembly and a power supply module are fixedly arranged in the second shell, a plurality of temperature measuring points are arranged in the black body plate, each temperature measuring point is provided with a temperature sensor electrically connected with the temperature control assembly, the temperature control assembly and the black body module are electrically connected with the power supply module, and the temperature control assembly is suitable for calculating according to PID (proportional integral differential) parameters to adjust the power of the semiconductor refrigerator.

Further, the PID parameters include proportional P (proportionality), integral i (integral), and derivative d (derivative), the P parameter can be proportional to the deviation signal of the control system in real time, and once the deviation is generated, the controller immediately generates the control action to reduce the deviation. As the offset value increases, the overshoot of the closed loop system increases, and the response speed of the system increases, but when the offset value increases to a certain extent, the system becomes unstable. The parameter I is mainly used for eliminating the static error and improving the non-difference of the system, and the larger the parameter I is, the smaller the overshoot of the closed-loop system is, and the slower the response speed of the system becomes. The parameter D can reduce overshoot, overcome oscillation, improve the stability of the system, accelerate the dynamic response speed of the system, and reduce the adjustment time, thereby improving the dynamic performance of the system. Proper adjustment P, I, D of the parameters can lead to good performance of the whole control system. PID is operated according to the function relation of proportion P, integral I and differential D according to the input deviation value, the operation result is used for controlling output, and the deviation of the controlled object can be effectively corrected through the combination of P, I, D, so that the controlled object can reach a stable state.

Further, the black plate is divided into four unit areas which are uniformly distributed, namely an upper left unit area, an upper right unit area, a lower left unit area and a lower right unit area, and each unit area is provided with a temperature measuring point.

Furthermore, the black plate is made of aluminum materials and has good heat conducting performance.

Furthermore, the semiconductor refrigerator is provided with four unit areas which are respectively and correspondingly arranged at the rear ends of the four unit areas of the black plate, the temperature control assembly adopts multipoint partition independent temperature control and comprises four temperature controllers, and each temperature controller is respectively and electrically connected with the corresponding semiconductor refrigerator and is independently controlled.

Further, the temperature controller is a digital display temperature controller and controls the semiconductor refrigerator in a direct-current voltage mode;

further, a touch screen is fixedly mounted on the second shell, and the touch screen is electrically connected with the temperature controller and is suitable for controlling the temperature of the temperature controller.

Furthermore, be equipped with the communication serial ports in the second casing, be equipped with first electric connector on the first casing, be equipped with the second electric connector of being connected with the communication serial ports electricity on the second casing, the temperature control module realizes being connected with the electricity of black body module through connecting first electric connector and second electric connector.

Further, the radiator unit includes transition plate, radiator fin subassembly and the radiator fin apron of fixed mounting in proper order at the semiconductor cooler rear end, radiator fin subassembly's top fixed mounting has radiator fan, the top of first casing is equipped with just to radiator fan's air exit, air exit department is equipped with the radiator fan safety cover of fixed mounting on first casing, the rear side of first casing is equipped with the radiating groove, radiator fin subassembly and radiator fin apron extend to the radiating groove.

Further, all be equipped with thermal-insulated subassembly between black body board and semiconductor refrigerator and the first casing, thermal-insulated subassembly is including the heat preservation of parcel on black body board and semiconductor refrigerator's the outer peripheral face, locates the heat insulating board between the front end of black body board and the first casing to and connect black body board and the thermal-insulated post of cab apron.

Furthermore, the heat insulation plate and the heat insulation column are FR-4 epoxy plates, so that the heat insulation plate has good machinability and excellent heat resistance and heat insulation performance; the heat preservation is polyurethane, has excellent heat-proof quality.

Further, the front end of blackboard board is equipped with prevents the subassembly that frosts, prevent that frosting subassembly includes cover and gas curtain before the protection that from the past after to fixed mounting in proper order on first casing and be located blackboard board front end, cover movable mounting before the protection has the window baffle, be equipped with gas inlet on the gas curtain, outside gas passes through gas inlet gets into the gas curtain and forms the gas curtain.

Furthermore, the air curtain comprises a frame and a cavity which is arranged in the frame and is connected with the air inlet, and the inner wall of the frame is provided with a plurality of small holes communicated with the cavity.

Furthermore, the rear side of the second shell is also provided with a USB interface, a fuse and a power supply interface, and one side of the touch screen is provided with a start-stop switch. The power supply interface supplies power to the start-stop switch, the start-stop switch supplies power to the power supply module, the whole system is controlled to start and stop, and the power supply system is simple in design and safe to use.

By adopting the technical scheme, the invention has the following beneficial effects:

(1) the temperature control module and the blackbody module are two independent modules, and the integrated equipment is divided into the two independent modules, so that the volume of the equipment can be reduced, the equipment is convenient to move and use, the manufacturing cost and the later maintenance cost are reduced, and when one module breaks down, the module can be independently maintained or replaced; the blackbody plate is provided with a plurality of temperature measuring points and is respectively provided with corresponding temperature sensors, so that multi-point temperature measurement is realized, the temperature uniformity and stability of the low-temperature large-area source blackbody are improved, the stabilization time is shortened, and the system safety is improved; the temperature control assembly calculates according to the PID parameters to adjust the power of the semiconductor cooler, improve the temperature stability and prolong the service life of the semiconductor cooler.

(2) The blackbody plate is divided into four unit areas which are uniformly distributed, namely an upper left unit area, an upper right unit area, a lower left unit area and a lower right unit area, heat is transferred and radiated from the middle of the blackbody plate to the periphery, so that the result that the periphery is hot in the middle is inevitably caused, and the temperature measuring uniformity and stability are further improved by arranging the four unit areas which are uniformly distributed and arranging temperature measuring points in each area.

(3) The four semiconductor refrigerators are respectively and correspondingly arranged at the rear ends of the four unit areas of the black body plate, the temperature control assembly adopts multipoint partition independent temperature control, and the four temperature controllers respectively and independently control the four semiconductor refrigerators, so that the overshoot of a system is reduced, the stabilization time is prolonged, the temperature distribution gradient on the surface of the black body plate is effectively improved, and the adverse effect caused by uneven temperature distribution is effectively reduced; temperature correction is carried out by utilizing multiple temperature points, so that the accuracy of the temperature is ensured; meanwhile, the temperature controller can adjust the voltage of the semiconductor refrigerator and change the relative voltage on the positive lead and the negative lead of the semiconductor refrigerator, so that the voltage direction is changed, the relative voltage value between the positive lead and the negative lead of the temperature controller can be positive or negative, the wiring direction does not need to be changed when the environmental temperature is changed by a user, and the semiconductor refrigerator is automatically controlled to realize refrigeration/heating.

(4) The temperature controller adopts a digital display temperature controller, so that parameters such as voltage, temperature and the like of the temperature controller can be observed more conveniently; the temperature controller adopts a direct-current voltage mode, firstly calculates an output voltage, then converts the power supply voltage into the required output voltage by a voltage conversion device of the temperature controller, has small temperature control power fluctuation by adopting the mode, can realize the resolution of 0.01 ℃ and the stability of +/-0.01 ℃, simultaneously has an automatic setting function, can automatically calculate an optimized PID coefficient, simplifies the setting difficulty of the PID coefficient, and obtains the temperature control performance of high speed, small overshoot and less oscillation, thereby prolonging the service life of the semiconductor refrigerator.

(5) The touch screen is fixedly arranged on the second shell, and the temperature controller is controlled by the touch screen, so that the operation is convenient.

(6) According to the invention, the temperature control module is electrically connected with the black body module by arranging the communication serial port, the first electric connector and the second electric connector, so that the two modules share one power supply module, the structural design is simple, and the manufacturing cost is saved.

(7) According to the semiconductor refrigerator, the heat dissipation assembly is arranged, external air flows through the heat dissipation fin assembly from the heat dissipation groove on the rear side of the first shell under the action of the heat dissipation fan and is exhausted through the air outlet in the upper end of the first shell, the heat dissipation fin assembly and the heat dissipation fin cover plate extend to the heat dissipation groove on the rear side, heat is exhausted from the air outlet as far as possible while the heat dissipation area of the heat dissipation fin assembly is increased, diffusion is avoided, the air outlet is arranged at the upper end due to the fact that the heat is upwards dissipated in a natural state, the heat dissipation performance is further improved, the refrigerating and heating performance of the semiconductor refrigerator is good, the temperature rising and lowering speed is high, and the equipment use performance is improved.

(8) The heat insulation assembly is further arranged, so that convection of the black plate and the semiconductor refrigerator with the outside air and heat transfer among the black plate, the shell and the heat dissipation fin assembly are effectively isolated, and the measurement accuracy of the device when the device is used for infrared calibration is ensured.

(9) The anti-frosting component is arranged, so that when a system to be tested needs to be calibrated, the window partition plate is drawn out, external air enters the air curtain and forms the air curtain, the air and the black body plate can be effectively prevented from carrying out convective heat exchange, the black body plate is effectively protected, and the surface frosting is avoided; when the measured system is calibrated, the window clapboard is inserted into the protective front cover immediately, so that the temperature error caused by introducing an optical window is avoided, the accuracy of the measurement result is ensured, the low-temperature surface source black body is effectively protected, and the influence of surface frosting on the temperature calibration of the instrument is avoided.

(10) The air curtain of the anti-frosting component comprises the cavity with the small holes, nitrogen is filled into the air curtain through the air inlet and is sprayed out of the small holes, so that the air curtain formed on the surface of the non-point source black body is more uniform, the convective heat exchange between air and the surface of the black body plate can be effectively prevented, the anti-frosting effect is further improved, and the defects of obvious surface temperature change and low temperature accuracy caused by directly blowing dry air to the surface of the black body plate are avoided.

Drawings

In order that the present disclosure may be more readily and clearly understood, reference is now made to the following detailed description of the present disclosure taken in conjunction with the accompanying drawings, in which:

FIG. 1 is a control schematic of the present invention;

FIG. 2 is a schematic view of the internal structure of the blackbody module in the top view direction according to the present invention;

FIG. 3 is a sectional view showing the internal structure of the blackbody module according to the present invention;

FIG. 4 is a rear view of the blackbody module of the present invention;

FIG. 5 is a schematic diagram of the internal structure of a temperature control module according to the present invention;

FIG. 6 is a rear view of the temperature control module of the present invention;

FIG. 7 is a schematic view of an air curtain structure of the anti-frosting assembly of the present invention.

The reference numbers in the drawings are:

the air conditioner comprises a first shell 1, a first electric connector 1-1, an air outlet 1-2 and a heat dissipation groove 1-3;

a black body plate 2;

a semiconductor refrigerator 3;

the heat dissipation device comprises a heat dissipation component 4, a transition plate 4-1, a heat dissipation fin component 4-2, a heat dissipation fin cover plate 4-3, a heat dissipation fan 4-4 and a heat dissipation fan protective cover 4-5;

the USB interface circuit comprises a second shell 5, a second electric connector 5-1, a USB interface 5-2, a fuse 5-3, a power supply interface 5-4 and a start-stop switch 5-5;

the temperature control component 6, the temperature controller 6-1 and the touch screen 6-2;

a power supply module 7;

a temperature sensor 8;

a communication serial port 9;

the heat insulation component 10, the heat insulation layer 10-1, the heat insulation plate 10-2 and the heat insulation column 10-3;

the anti-frosting module 11, the protective front cover 11-1, the air curtain 11-2, the frame 11-2-1, the small hole 11-2-2, the window partition plate 11-3 and the air connector 11-4.

Detailed Description

In order to better understand the technical solution, the technical solution will be described in detail with reference to the drawings and the specific embodiments.

(example 1)

The multi-point temperature control low-temperature large-area source blackbody shown in the figures 1 to 7 consists of two split type modules, namely a blackbody module and a temperature control module, and integrated equipment is divided into two independent modules, so that the size of the equipment can be reduced, the equipment is convenient to move and use, the manufacturing cost and the later maintenance cost are reduced, and when one module breaks down, the integrated equipment can be independently maintained or replaced. The blackbody module comprises a first shell 1, and a blackbody plate 2, a semiconductor refrigerator 3 and a heat dissipation assembly 4 which are sequentially arranged in the first shell 1. The temperature control module comprises a second housing 5, and a temperature control assembly 6 and a power module 7 fixedly mounted in the second housing 5. Be equipped with a plurality of temperature measurement points in the black body board 2, every temperature measurement point all is equipped with the temperature sensor 8 of being connected with temperature control assembly 6 electricity, realizes the multiple spot temperature measurement, improves the temperature homogeneity and the stability of low temperature large area source black body, shortens the stabilization time, improves system security nature. Wherein temperature control assembly 6 and blackbody module all are connected with power module 7 electricity, gather the temperature feedback through temperature sensor 8 and give temperature control assembly 6, and temperature control assembly 6 calculates the power of adjusting semiconductor cooler 3 according to the PID parameter again to improve temperature stability, prolong semiconductor cooler 3's life.

Specifically, a communication serial port 9 is arranged in the second shell 5, a first electric connector 1-1 is arranged on the first shell 1, a second electric connector 5-1 electrically connected with the communication serial port 9 is arranged on the second shell 5, and the temperature control module is electrically connected with the black body module through the connection of the first electric connector 1-1 and the second electric connector 5-1. The rear side of the second shell 5 is also provided with a USB interface 5-2, a fuse 5-3 and a power supply interface 5-4, and the front side is provided with a start-stop switch 5-5. The power supply interface 5-4 supplies power to the start-stop switch 5-5, the start-stop switch 5-5 supplies power to the power module 7, and the whole equipment system is controlled to start and stop, so that the design is simple, and the use is safe.

In this embodiment, the first casing 1 and the second casing 5 are both made of steel plates with a thickness of 3mm and a material of Q235-a, so that the overall shape strength is good. The black plate 2 is made of aluminum materials, has good heat conducting performance, is uniformly distributed with a plurality of pyramidal bulges on the front surface, and has high effective emissivity reaching 0.99 +/-0.01. In this embodiment, the black plate 2 is divided into four evenly distributed unit areas, namely, an upper left unit area, an upper right unit area, a lower left unit area and a lower right unit area, each unit area is provided with a temperature measuring point, heat is transferred and radiated from the middle of the black plate 2 to the periphery, and therefore the result that the middle is hot and the periphery is cool is inevitably caused.

The temperature sensor 8 uses a 10k 1% B3950 NTC thermistor, and has four temperature measurement points inserted into the black plate 2 to collect the temperatures of the four unit regions of the black plate 2. The semiconductor refrigerator 3 is provided with four semiconductor refrigerators which are respectively and correspondingly arranged at the rear ends of the four unit areas of the black plate 2, the maximum temperature difference is 60 ℃, the maximum current is 18A, the maximum voltage is 18V, the flow direction of heat is changed by changing the current direction, so that the refrigerator can refrigerate and heat, the test requirements of the equipment on different environmental temperatures are met, the refrigerator has a larger overall dimension of 80 x 120mm, and the uniformity of the surface temperature of the black plate 2 is effectively ensured to be less than or equal to 0.15 ℃.

The temperature control component 6 adopts multipoint zone independent temperature control and comprises four independent temperature controllers 6-1, and each temperature controller 6-1 is electrically connected with a corresponding semiconductor refrigerator 3 and independently controlled. The temperature control assembly 6 adopts multipoint zone independent temperature control, and four semiconductor refrigerators 3 are respectively and independently controlled by four temperature controllers 6-1, so that system overshoot is reduced, the stabilization time is prolonged, the temperature distribution gradient on the surface of the black body plate 2 is effectively improved, and adverse effects caused by uneven temperature distribution are effectively reduced; temperature correction is carried out by utilizing multiple temperature points, so that the accuracy of the temperature is ensured; meanwhile, the temperature controller 6-1 can not only adjust the voltage of the semiconductor refrigerator 3, but also change the relative voltage of the positive and negative leads of the semiconductor refrigerator 3, so as to change the voltage direction, therefore, the relative voltage value between the positive and negative leads of the temperature controller 6-1 can be positive or negative, the wiring direction does not need to be changed when the environmental temperature changes by a user, and the semiconductor refrigerator 3 is automatically controlled to realize refrigeration/heating.

The traditional temperature controller of the low-temperature large-area source blackbody adopts a pulse voltage output mode to control the semiconductor refrigerator, and the voltage waveform on the semiconductor refrigerator is square pulse, so that the temperature control power has sudden change, the temperature stability is not high, the general stability is +/-1 ℃, and the service life of the semiconductor refrigerator can be shortened due to the sudden change of the voltage. The temperature controller 6-1 is a digital display temperature controller and controls a semiconductor refrigerator by adopting a direct current voltage mode, the model is TCM1031, and parameters such as voltage and temperature of the temperature controller 6-1 can be observed more conveniently. By adopting a direct-current voltage mode, firstly calculating an output voltage, and then converting the power supply voltage into the required output voltage by a voltage conversion device of the temperature controller 6-1, the temperature control power fluctuation adopting the mode is small, the resolution ratio of 0.01 ℃ and the stability of +/-0.01 ℃ can be realized, meanwhile, the automatic setting function is realized, the optimized PID coefficient can be automatically calculated, the setting difficulty of the PID coefficient is simplified, and the temperature control performance with high speed, small overshoot and less oscillation is obtained, so that the service life of the semiconductor refrigerator 3 is prolonged. The second shell 5 of the embodiment is fixedly provided with the touch screen 6-2 electrically connected with the temperature controller 6-1, the temperature controller 6-1 is controlled by the touch screen 6-2, the operation is convenient, the temperature setting range is 0-80 ℃, and the use requirements of most users are met.

The heat dissipation assembly 4 comprises a transition plate 4-1, a heat dissipation fin assembly 4-2 and a heat dissipation fin cover plate 4-3 which are fixedly arranged at the rear end of the semiconductor refrigerator 3 in sequence, a heat dissipation fan 4-4 is fixedly arranged above the heat dissipation fin assembly 4-2, an air outlet 1-2 which is opposite to the heat dissipation fan 4-4 is formed in the top of the first shell 1, and a heat dissipation fan protective cover 4-5 which is fixedly arranged on the first shell 1 is arranged at the air outlet 1-2. The rear side of the first shell 1 is provided with a heat radiating groove 1-3, the heat radiating fin assembly 4-2 and the heat radiating fin cover plate 4-3 extend to the heat radiating groove 1-3, so that the heat radiating area of the heat radiating fin assembly 4-2 is increased, and meanwhile, heat is exhausted from an air outlet as far as possible, and diffusion is avoided. External air flows through the radiating fin component 4-2 from the radiating groove 1-3 at the rear side of the first shell 1 under the action of the radiating fan 4-4 and is exhausted through the air outlet 1-2 at the upper end of the first shell 1, and the air outlet 1-2 is arranged at the upper end of the first shell 1 because heat is radiated upwards in a natural state, so that the radiating performance is further improved, the refrigerating and heating performance of the semiconductor refrigerator 3 is excellent, the temperature rising and lowering speed is high, and the equipment use performance is improved.

In order to isolate the convection of the black plate 2 and the semiconductor refrigerator 3 from the outside and the heat transfer between the black plate 2 and the first casing 1 and the heat dissipation fin assembly 4-2, heat insulation assemblies 10 are respectively arranged between the black plate 2 and the semiconductor refrigerator 3 and the first casing 1, and comprise an insulating layer 10-1, a heat insulation plate 10-2 and a heat insulation column 10-3. The cold end of the semiconductor refrigerator 3 is coated with heat-conducting silicone grease and is connected with the black body plate 2, and the hot end is coated with heat-conducting silicone grease and is connected with the transition plate 4-1. The heat insulation layer 10-1 is wrapped on the outer peripheral surfaces of the black body plate 2 and the semiconductor refrigerator 3, the heat insulation plate 10-2 is arranged between the front end of the black body plate 2 and the first shell 1, and the heat insulation column 10-3 is connected with the black body plate 2 and the transition plate 4-1, so that the measurement accuracy of the device used for infrared calibration is guaranteed. Wherein the heat-insulating layer 10-1 is made of polyurethane and has excellent heat-insulating property, the heat-insulating plate 10-2 and the heat-insulating column 10-3 are made of FR-4 epoxy boards and have good machinability and excellent heat-resisting and heat-insulating properties.

Because the follow-up temperature transmission of the temperature accuracy direct influence of low temperature face source blackbody, in order to prevent that low temperature during operation air and face source blackbody surface from carrying out heat convection, produce the condition of frosting, and influence the check-up of instrument temperature, the front end of the blackbody board 2 of this embodiment still is equipped with prevents frosting subassembly 11. The existing common frost prevention schemes are divided into three types: the first method is to directly blow dry gas to the surface of the surface source black body, and the scheme has the advantages that the anti-frosting effect is obvious, but the surface temperature change of the surface source black body is obvious and the temperature accuracy is not high due to the difference between the nitrogen temperature and the surface source black body temperature; the second is to encapsulate the surface of the surface source black body in a box filled with dry nitrogen and seal the surface source black body by an optical window, and the scheme has the advantages that the design is simple, but because the transmittance of the optical window cannot be 1, the temperature error of the window is introduced, the measurement result needs to be corrected when being calculated, and on the other hand, the processing cost is high because the transmittance of the optical window is more than 0.99; the third is to place the surface source black body and the measured system in the cover filled with nitrogen, the scheme has the advantages that no other device introduces temperature error between the measured system and the surface source black body, but various measured systems with various volumes can appear due to various types of the measured systems, and the distance between the measured system and the surface source black body is far and near, the scheme can need to install various covers aiming at various measured systems, and the cost is high due to various types and large volume. The present embodiment can effectively solve the problems occurring in the above three schemes by adding the anti-frosting component 11.

Specifically, the anti-frosting assembly 11 comprises a protective front cover 11-1 and an air curtain 11-2 which are fixedly mounted on the first shell 1 from front to back in sequence and located at the front end of the black body plate 2, a window partition plate 11-3 capable of being drawn up and down is mounted on the protective front cover 11-1, and an external air source is preferably nitrogen in the embodiment. The gas curtain 11-2 is provided with three gas inlets, each gas inlet is provided with a gas joint 11-4, external gas enters the gas curtain 11-2 through the gas inlets and forms a gas curtain, the uniformity of the gas curtain in front of the black plate 2 is ensured, and the phenomenon that only one part of the gas curtain is exposed out of nitrogen to cause condensation on other surfaces which are not blown with nitrogen is avoided. The gas joint 11-4 is a copper nickel plating MPL6-M6 right-angle pneumatic quick connector which can be quickly connected with a PU pipe and a nylon pipe and is convenient to use. The protective front cover 11-1 is a POM (polyoxymethylene) piece, the air curtain 11-2 is a white photosensitive resin 3D printing piece, and the window partition plate 11-3 is a transparent organic glass cover, so that the protective front cover is high in transparency, good in processability and low in cost, and the surface state of the surface source black body can be observed conveniently.

The upper end surface of the protective front cover 11-1 is provided with a through groove, the inner wall of the bottom is provided with a groove, and the window clapboard 11-3 passes through the through groove and is inserted into the groove to realize drawing and fixing. The air curtain 11-2 comprises a frame 11-2-1 and a cavity which is arranged in the frame 11-2-1 and is connected with the air inlet 11-4, and the inner wall of the frame 11-2-1 is provided with a plurality of small holes 11-2-2 communicated with the cavity. When a system to be measured needs to be calibrated, the window partition plate 11-3 is drawn out, the gas connector 11-4 and an external gas source are connected through a gas pipe, nitrogen enters the gas curtain 11-2 through the gas inlet, and is sprayed out of each small hole 11-2-2, so that a uniform gas curtain is formed on the surface of the surface source black body, the air and the surface source black body surface can be effectively prevented from carrying out convective heat exchange, and the defects that the surface temperature change of the surface source black body is obvious and the temperature accuracy is low due to the fact that gas is directly blown and dried to the surface of the surface source black body are avoided, and the measurement accuracy of the surface source black body of the device is guaranteed.

The embodiment improves the temperature uniformity, stability and accuracy of the low-temperature large-area source black body, and shortens the stabilization time. Temperature control module and blackbody module are two independent type modules, divide into two independent modules with integral type equipment, can reduce the volume of equipment, are convenient for remove and use, reduce simultaneously and make and later stage cost of maintenance, but when one of them module breaks down maintenance alone or change.

The temperature controller 6-1 is operated and controlled through the touch screen 6-2 to control the semiconductor refrigerator 3 to work, the power of the semiconductor refrigerator 3 is adjusted through calculation according to PID parameters, and the temperature stability is improved; the black body plate 3 is provided with a plurality of temperature measuring points and corresponding temperature sensors 8 respectively, so that multipoint temperature measurement is realized, and the temperature uniformity and stability of the low-temperature large-area source black body are improved. The temperature control component 6 adopts multipoint partition independent temperature control, and the four temperature controllers 6-1 respectively and independently control the four semiconductor refrigerators 3, thereby reducing system overshoot, improving the stabilization time, effectively improving the temperature distribution gradient on the surface of the black body plate 2, effectively reducing the adverse effect caused by uneven temperature distribution, and realizing the refrigeration/heating of the automatically controlled semiconductor refrigerators 3.

In addition, set up through the front end at black body board 2 and prevent frosting subassembly 11, effectively protect low temperature face source black body, avoid the surface to frost, can improve the temperature accuracy of low temperature face source black body to convenient to use.

The above-mentioned embodiments are intended to illustrate the objects, technical solutions and advantages of the present invention in further detail, and it should be understood that the above-mentioned embodiments are only exemplary embodiments of the present invention, and are not intended to limit the present invention, and any modifications, equivalents, improvements and the like made within the spirit and principle of the present invention should be included in the protection scope of the present invention.