A biological sample freezing rack capable of zoned temperature control and a program temperature control device

Abstract

The present invention provides a biological sample freezing rack and program temperature control equipment with zoned temperature control, characterized in that it includes a heat sink cold plate, a cooling unit and a control module, wherein the upper surface of the heat sink cold plate is connected to a plurality of independent cooling units, the control module is connected to and controls the cooling units, and the lower surface of the heat sink cold plate is connected to a refrigeration source; the cooling unit includes a sample slot, a heating element, a temperature sensor and a heat insulation cover. The beneficial effect of the present invention is that by designing independent cooling units and heat sinks, the equipment can independently operate in batches and multiple channels on samples collected at different times, and the control module receives data from the temperature sensor of the independent cooling unit, adjusts the working power of the heating element, and makes the frozen sample cool at the optimal cooling rate to achieve the best freezing effect.

Description

Technical Field

[0001] The invention relates to the field of biological cryogenic storage, and in particular to a biological sample freezing rack capable of zoned temperature control and a program temperature control device. Background Art

[0002] In the process of preserving cells or biological samples, using appropriate methods to freeze the samples to ultra-low temperatures (below -80 degrees Celsius) and keep them at this temperature for a long period of time is a key step in biological freezing technology. The commonly used preservation method is to suspend the sample in a solution with a cryoprotectant, and cool it to ultra-low temperatures at a certain freezing rate for long-term storage. Among them, the method that can meet the precise control of the cooling rate is to use a program cooling instrument, which uses software to lower the temperature according to a preset curve for specific biological samples.

[0003] The existing mainstream technology is to use a liquid nitrogen refrigeration program cooling instrument, which controls the liquid nitrogen injection flow rate to cool the sample freezing chamber according to a preset cooling curve. This method generally has the disadvantages of large liquid nitrogen consumption, large temperature control error, cumbersome safety operation, potential risk of contaminating biological samples when liquid nitrogen contacts the sample, and bulky instrument structure that cannot be easily transported. More importantly, due to the long time required for a single operation and the large amount of liquid nitrogen consumption, a certain number of biological samples are usually collected for batch operation. In the use environment of a hospital or scientific laboratory, a small amount of precious samples, such as various experimental cell samples, oocytes, patient stem cells, etc., need to be frozen at a controlled rate as soon as possible when collected, so as to obtain higher activity when thawed to ensure the effectiveness of the next experiment / treatment. Therefore, in order to meet the needs of the rapidly developing biomedicine for cryopreservation of biological samples, and to accurately control the cooling process of samples and realize storage and retrieval at any time, the present invention provides a biological sample freezing rack with zoned temperature control and a programmed cooling device. The sample freezing rack has multiple independent cooling areas, and multiple groups of samples can be operated in batches without removing the samples. The sample freezing rack can be connected to various refrigeration equipment to realize the programmed cooling function, and also has the function of short-term low-temperature storage of biological samples. Summary of the invention

[0004] In order to solve the above technical problems, the present invention discloses a biological sample freezing rack with zoned temperature control and a program temperature control device. The technical solution of the present invention is implemented as follows:

[0005] A biological sample freezing rack with zoned temperature control comprises a heat sink, a cooling unit and a control module; wherein the upper surface of the heat sink is connected to a plurality of independent cooling units, the control module is connected to and controls the cooling units, and the cooling unit comprises a sample slot, a heating element, a temperature sensor and a heat insulation cover; the heating element and the temperature sensor are located on the side wall of the sample slot, and the heat insulation cover is located on the upper part of the sample slot.

[0006] Preferably, the heat sink includes a reference hole, a concave-convex structure is arranged on the upper surface of the heat sink, the cooling unit includes a sample holder and a connecting column, the connecting column is located at the bottom of the sample holder, the connecting column is matched and fixed with the reference hole, multiple circuit channels are arranged inside the heat sink, and the upper surface of the heat sink is covered with insulating material.

[0007] Preferably, the aperture size of the sample slot is 1-100 mm, the depth of the sample slot is 1-200 mm, and the number of sample holes in the sample slot is 1 or more.

[0008] Preferably, a thermal connector is further included, and the cooling unit is fixedly connected to the heat sink through the thermal connector.

[0009] Preferably, the thermal connector is made of sapphire and has a thickness of 0.1-20 mm.

[0010] Preferably, the thermal connector comprises a micro-expansion low temperature thermal switch.

[0011] A programmed cooling device comprises a biological sample freezing rack with zoned temperature control, a sample freezing rack shell and a refrigeration unit as described in any embodiment of the present disclosure; the refrigeration unit comprises a refrigeration source, which is located inside the refrigeration unit and contacts the lower surface of the heat sink cold plate.

[0012] Preferably, the cooling source is a refrigerator; the refrigerator comprises a cold head, and the cold head is connected to the lower surface of the heat sink cold plate.

[0013] Preferably, the cooling source is a refrigerant; the cooling unit comprises a Dewar vessel, the refrigerant is loaded in the Dewar vessel, and an opening of the Dewar vessel is coupled to the lower surface of the heat sink cold plate.

[0014] The implementation of the technical solution of the present invention can solve the technical problems in the prior art of large liquid nitrogen consumption, large temperature control error, cumbersome safety operation, potential risk of contaminating biological samples when liquid nitrogen contacts samples, and bulky instrument structure that cannot be easily transported; the implementation of the technical solution of the present invention can achieve batch operation of multiple groups of samples without removing the samples by setting multiple independent cooling areas on the sample freezing rack, and the sample freezing rack can be connected to various refrigeration equipment to realize the programmed cooling function, and also has the technical effect of short-term low-temperature storage function of biological samples. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only one embodiment of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] The same parts are denoted by the same reference numerals. It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the following description refer to directions in the drawings, and the words "bottom" and "top", "inner" and "outer" refer to directions toward or away from the geometric center of a specific component, respectively.

[0017] Figure 1 The schematic diagram is a biological sample freezing rack with zoned temperature control;

[0018] Figure 2 The schematic diagram is a structure of a biological sample freezing rack capable of zoned temperature control;

[0019] Figure 3 It is a structural schematic diagram of Example 2;

[0020] Figure 4 It is a schematic diagram of the connection structure between the thermal connector and the heat sink cold plate;

[0021] Figure 5 This is a schematic diagram of the structure of Example 4.

[0022] In the above drawings, the figure numbers represent:

[0023] 1. Heat sink cold plate

[0024] 1-1, reference hole

[0025] 2. Cooling unit

[0026] 2-1, sample tank

[0027] 2-2, Heating element

[0028] 2-3, Temperature sensor

[0029] 2-4, heat insulation cover

[0030] 2-5, sample holder

[0031] 2-6, connecting column

[0032] 3. Control module

[0033] 4. Thermal connector

[0034] 5. Sample freezing rack shell

[0035] 6. Cooling unit

[0036] 6-1, Cold Head

[0037] 6-2, Dewar's Vessel DETAILED DESCRIPTION

[0038] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0039] Example 1

[0040] In a specific embodiment 1, Figure 1 and Figure 2 As shown, a biological sample freezing rack with zoned temperature control includes a heat sink cold plate 1, a cooling unit 2 and a control module 3; wherein, a plurality of independent cooling units 2 are connected to the upper surface of the heat sink cold plate 1, the control module 3 is connected to and controls the cooling unit 2, and the cooling unit 2 includes a sample slot 2-1, a heating element 2-2, a temperature sensor 2-3 and an insulating cover 2-4; the heating element 2-2 and the temperature sensor 2-3 are located on the side wall of the sample slot 2-1, and the insulating cover 2-4 is located on the upper part of the sample slot 2-1.

[0041] In this embodiment, the heat sink cold plate 1 is made of metal materials with high thermal conductivity, such as aluminum, copper, alloy, etc., and the upper end of the heat sink cold plate 1 is a plurality of independent cooling units 2, and a single cooling unit 2 includes a sample slot 2-1, a heating element 2-2, a temperature sensor 2-3 and a heat insulation cover 2-4. The single sample slot 2-1 is made of metal materials with high thermal conductivity, such as aluminum, copper, alloy, etc., and can be used to load sample tubes. The heat insulation cover 2-4 on the upper part of the sample slot 2-1 can cover the exposed part of the sample tube to isolate the sample tube from the influence of the change of the surrounding thermal energy. The side wall of the single sample slot 2-1 is fixed with a heating element 2-2 and a temperature sensor 2-3. The temperature sensor 2-3 collects the temperature of the sample slot 2-1 (i.e., represents the current sample temperature) and feeds it back to the control module 3. The control module 3 controls the power of the heating element 2-2 according to the feedback temperature. The control module 3 can be a single-chip microcomputer, POC, PC system, etc. containing a processor. The temperature sensor 2-3 can be various types of thermocouple thermometers and thermal resistance thermometers, and the heating element 2-2 can be various types of heaters, such as ceramic heaters, semiconductor heaters, film heaters, etc. The power of the heating element 2-2 can be 1W to 200W. When in use, the lower surface of the heat sink cold plate 1 can directly contact the cooling source, and the cooling source can be liquid nitrogen, liquid helium, liquid hydrogen, liquid fluorine, liquid oxygen, liquid methane, and various types of Stirling refrigerators, GM refrigerators, JT refrigerators, pulse tube refrigerators, etc. Since the cooling capacity provided by the cooling source is sufficient, the temperature of the heat sink cold plate 1 is not affected by the change in the thermal energy of the upper cooling unit 2, and the heating elements 2-2 and temperature sensors 2-3 of multiple cooling units 2 are independent of each other, so that a single cooling unit 2 can be independently subjected to program cooling, cryopreservation, rapid rewarming and other operations, so that multiple cooling units 2 can be cooled, stored, and rewarmed in time and in different zones, and different characteristics of biological samples can be cooled at different optimal rates at the same time to achieve the best cryopreservation effect.

[0042] Taking the treatment of two samples A and B to be frozen as an example, in actual use, when the heat sink cold plate 1 is connected to a cooling source such as a refrigerant or a refrigerator, the temperature of the heat sink cold plate 1 will drop rapidly to an ultra-low temperature, and at the same time, the heat sink cold plate 1 will continue to be in a low temperature state, and the temperature of the cooling units 2A and 2B without starting the heating elements 2-2A and 2-2B will also drop to an ultra-low temperature. Since the initial temperature of the samples A and B to be frozen is generally close to room temperature or refrigeration temperature, before the samples are placed in the sample slots 2-1A and 2-1B for controlled cooling, the heating elements 2-2A and 2-2B need to be started to maintain the initial temperature of the sample slots 2-1A and 2-1B at 4°C to 20°C. After the temperature of the sample slots 2-1A and 2-1B reaches the initial set value, sample A can be placed first, and the cooling rate vA (v, t) of the sample slot 2-1A is preset through the control module 3, and the program cooling process is started. Sample B can be placed at any time, and the cooling rate vB(v,t) of the sample slot 2-1B is preset by the control module 3 to start the program cooling process. During the program cooling process, the temperature sensors 2-3A and B read the current temperature of the sample slots 2-1A and B respectively and feed back to the control module 3. The control module 3 adjusts the power of the heating elements 2-2A and 2-2B according to the temperature, so that the temperature of the sample slots 2-1A and 2-1B changes according to the preset cooling curve, thereby achieving the purpose of accurate cooling. When the temperature of the sample slots 2-1A and 2-1B drops to the set value, the control module 3 will maintain the heating elements 2-2A and 2-2B working at the current power value, and continuously monitor the temperature of the sample slots 2-1A and 2-1B to keep it stable. If necessary, the control module 3 can also control the heating elements 2-2A and 2-2B to heat the sample slots 2-1A and 2-1B in the low temperature state, so that the frozen samples can be quickly reheated.

[0043] This embodiment has multiple independent cooling areas, and multiple groups of samples can be operated in batches without removing the samples, so as to achieve storage and retrieval at any time, shorten the waiting time from sample collection to freezing, improve the sample recovery effect, and also can simultaneously cool multiple samples at different optimal cooling rates to achieve the best cryopreservation effect. The program cooling equipment using a refrigerator as a cooling source has a compact structure and is equipped with a mobile power supply. It can be used in scenarios such as long-distance transportation of biological samples and collection of biological samples in the field and at multiple locations. The program cooling equipment using a refrigerant as a cooling source has low refrigerant consumption and high cooling efficiency, and can realize batch operation of a large number of samples. It is suitable for large-scale GMP cell production centers and biological sample banks that need to store a large number of biological samples.

[0044] Example 2

[0045] In a preferred embodiment 2, Figure 1 , Figure 2 and Figure 3As shown, the heat sink cold plate 1 includes a reference hole 1-1, and a concave-convex structure is arranged on the upper surface of the heat sink cold plate 1. The cooling unit 2 includes a sample holder 2-5 and a connecting column 2-6. The connecting column 2-6 is located at the bottom of the sample holder 2-5, and the connecting column 2-6 is matched and fixed with the reference hole 1-1. Multiple circuit channels are arranged inside the heat sink cold plate 1, and the upper surface of the heat sink cold plate 1 is covered with insulating material.

[0046] In this embodiment, the upper surface of the heat sink cold plate 1 is designed as a concave-convex structure, and the cooling unit 2 is fixed on the concave-convex structure corresponding to the heat sink cold plate 1 in a plug-in manner through the sample holder 2-5. The sample holder 2-5 can adopt a multi-pin plug-in type sample holder commonly used for low-temperature sample measurement. The bottom of the sample holder 2-5 is provided with a connecting column 2-6, such as 10pin or 12pin, etc., and the convex part of the heat sink cold plate 1 is provided with a reference hole 1-1, and the hole diameter can just accommodate the connecting column 2-6. The cooling unit 2 is fixed on the sample holder 2-5, and the control circuit of the heating element 2-2 and the temperature sensor 2-3 in the cooling unit 2 is connected to the reference hole 1-1 on the heat sink cold plate 1 through the connecting column 2-6 of the sample holder 2-5, and then connected to the control module 3 through the multi-channel circuit inside the heat sink cold plate 1, which can avoid excessive exposure of wires to the outside, and the cooling unit 2 is easy to plug and unplug, repair and replace, and the main body of the sample holder 2-5 can be selected from metal materials with good thermal conductivity. At the same time, the surface of the heat sink cold plate 1 is covered with insulating material, so that the groove gaps and the gaps between multiple cooling units 2 are filled with insulating material. The insulating material and the insulating cover 2-4 are used to prevent the cooling unit 2 from being affected by the surrounding heat radiation, and at the same time, a single independent cooling unit 2 only undergoes contact heat conduction with the heat sink cold plate 1.

[0047] In a preferred embodiment, the aperture size of the sample slot 2-1 is 1-100 mm, the depth of the sample slot 2-1 is 1-200 mm, and the number of sample holes in the sample slot 2-1 is 1 or more.

[0048] Since the sample slot 2-1 is used to load sample tubes, in actual biological cryopreservation, sample tubes have different specifications, such as cryopreservation tubes, wheat straws, vaccines, medicines, blood bags, etc., the internal aperture size and depth of the sample slot 2-1 should also match sample tubes of different specifications. The depth of the sample slot 2-1 should expose part of the tube body and tube cap of the sample tube to facilitate storage and retrieval operations. A single sample slot 2-1 can accommodate at least one frozen sample, and can also be designed to match various multi-well plates and SBS standard multi-well plates to accommodate multiple samples, which is convenient for use in combination with a cell production line. When the sample tube to be processed is a wheat straw, the upper surface of the sample slot 2-1 is designed as a horizontal groove to accommodate a slender wheat straw. When the sample to be processed is a blood bag, the upper surface of the sample slot 2-1 is designed as a plane.

[0049] Example 3

[0050] In a preferred embodiment 3, Figure 1 , Figure 2 and Figure 4 As shown, a thermal connector 4 is also included, and the cooling unit 2 is connected and fixed to the heat sink 1 via the thermal connector 4 .

[0051] When the cooling capacity provided by the refrigerant and the refrigerator is very large and the temperature of the heat sink 1 is extremely low (e.g., less than -120°C), if the sample slot 2-1 is in direct contact with the heat sink 1, the power of the heating element 2-2 may not be sufficient to maintain the initial temperature of the sample slot stable within the temperature range of 4°C to 20°C. Therefore, a thermal connector 4 is used. When the heating element 2-2 is started to increase the temperature of the sample slot 2-1, the thermal connector 4 is affected by the temperature change of the sample slot 2-1. The temperature of the thermal connector 4 increases while the thermal conductivity decreases, which reduces the heat transfer from the sample slot 2-1 to the heat sink 1 and promotes the further increase of the temperature of the sample slot 2-1. The heating element 2-2 can work at a lower power to maintain the initial temperature of the sample slot stable within the temperature range of 4°C to 20°C. After the cooling program is started, the thermal conductivity of the thermal connector 4 increases as the temperature of the sample slot 2-1 decreases, which promotes the heat transfer from the sample slot 2-1 to the heat sink 1. The adjustable cooling rate range is larger and can meet the freezing requirements of more types of biological samples.

[0052] In a preferred embodiment, the thermal connector 4 is made of sapphire, and the thickness of the thermal connector 4 is 0.1-20 mm.

[0053] Because the thermal conductivity of sapphire increases with decreasing temperature and decreases with increasing temperature within a temperature range above 30K, it can exhibit weak thermal conductivity at high temperatures and good thermal conductivity at low temperatures. This can effectively meet the need to control the temperature increase and decrease of the sample tank 2-1 using the heating element 2-2.

[0054] In a preferred embodiment, the thermal connector 4 comprises a micro-expansion low-temperature thermal switch.

[0055] In this embodiment, the thermal connector 4 directly adopts a micro-expansion low-temperature thermal switch, which utilizes the different expansion and contraction rates of two different materials to achieve the effect of thermal conductivity of the thermal connector 4 being disconnected at high temperature and closed at low temperature. It can also meet the needs of controlling the heating and cooling of the sample slot 2-1 using the heating element 2-2.

[0056] Example 4

[0057] In a specific embodiment 4, a programmed cooling device, such as Figure 1 , Figure 2 and Figure 5As shown, it includes a biological sample freezing rack with zoned temperature control, a sample freezing rack shell 5 and a refrigeration unit 6 as in any embodiment of the present disclosure; the refrigeration unit 6 includes a refrigeration source, which is located inside the refrigeration unit 6 and contacts the lower surface of the heat sink cold plate 1.

[0058] In this embodiment, a programmed cooling device for a biological sample freezing rack with zoned temperature control as in any embodiment of the present disclosure is disclosed. In order to isolate the influence of external environmental heat, the sample freezing rack shell 5 can be designed as a double-layer vacuum Dewar flask, or as a vacuum insulation panel and a polyurethane foam composite material and other insulating devices. The cooling source of the refrigeration unit 6 can adopt various types of refrigeration equipment or refrigerants, such as liquid nitrogen, liquid helium, liquid hydrogen, liquid fluorine, liquid oxygen, liquid methane, and various types of Stirling refrigerators, GM refrigerators, JT refrigerators, pulse tube refrigerators, etc.

[0059] In a preferred embodiment, the cooling source is a refrigerator; the refrigerator includes a cold head 6 - 1 , and the cold head 6 - 1 is connected to the lower surface of the heat sink cold plate 1 .

[0060] When a refrigerator is used as the cooling source, the cold head 6-1 of the refrigerator is in direct contact with the lower surface of the heat sink cold plate 1, and the heat of the sample freezing rack is removed by contact heat conduction. There is a shock-absorbing device between the refrigerator and the sample freezing rack to reduce the potential damage to the biological sample caused by vibration. The program cooling device using a single refrigerator has a compact structure and is equipped with a mobile power supply. It can be used in long-distance transportation of biological samples, field, multi-location biological sample collection, and on-the-go storage and retrieval scenarios.

[0061] In a preferred embodiment, the cooling source is a refrigerant; the cooling unit 6 includes a Dewar vessel 6 - 2 , the refrigerant is loaded in the Dewar vessel 6 - 2 , and the opening of the Dewar vessel 6 - 2 is coupled to the lower surface of the heat sink cold plate 1 .

[0062] When the cooling source of the refrigeration unit 6 adopts various types of refrigerants, the refrigerant can be loaded into the Dewar vessel 6-2. The opening of the Dewar vessel 6-2 is coupled with the heat sink cold plate 1 to remove the heat of the sample freezing rack by contact heat conduction. Compared with the traditional liquid nitrogen injection program cooling instrument, the direct contact refrigeration efficiency of liquid nitrogen in this device is high. Except for the volatile loss of liquid nitrogen itself, the consumption is small, and it does not come into direct contact with the biological sample, eliminating the possibility of contamination.

[0063] In the present invention:

[0064] The sample freezing rack can cool samples collected at different times in batches and independently through multiple channels, shortening the waiting time from sample collection to freezing and improving the sample recovery effect. It can also cool multiple samples at different optimal cooling rates at the same time to achieve the best freezing preservation effect.

[0065] The sample freezing rack is coupled with a refrigerant cooling source to realize a programmed cooling process with lower refrigerant consumption.

[0066] The sample freezing rack coupled with the refrigeration mechanism cooling source can achieve liquid nitrogen-free refrigeration, avoiding liquid nitrogen contamination of biological samples, and the operation is safe and requires no consumables.

[0067] The cooling units 2 of the sample freezing rack are independent of each other. The samples that have completed cooling do not need to be taken out in a short period of time and are not affected by the cooling operations of other samples. The sample freezing rack can have a short-term low-temperature storage function.

[0068] The independent cooling unit 2 can be designed with corresponding aperture sizes for different specifications of cryopreservation tubes and can be disassembled and replaced. The independent cooling unit 2 can be designed to match various multi-well plates and SBS standard multi-well plates, which is convenient for use in combination with intelligent robot technology and high-throughput screening.

[0069] Each cooling unit 2 is temperature-regulated by a heating element 2-2 and a temperature sensor 2-3, which can control the rapid reheating of the sample in addition to controlling the temperature drop.

[0070] The temperature can be controlled accurately to ±0.1 degrees Celsius.

[0071] It should be pointed out that the above is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A biological sample freezing rack with zoned temperature control, characterized in that: It includes a heat sink cold plate, a cooling unit and a control module; wherein the heat sink cold plate is used to connect to a cooling source and a plurality of independent cooling units are connected to the upper surface of the heat sink cold plate, the control module connects and controls the cooling unit, and the cooling unit includes a sample slot, a heating element, a temperature sensor and an insulating cover; the heating element and the temperature sensor are located on the side wall of the sample slot, and the insulating cover is located on the upper part of the sample slot.

2. A biological sample freezing rack with zoned temperature control according to claim 1, characterized in that: The heat sink cold plate includes a reference hole, and a concave-convex structure is arranged on the upper surface of the heat sink cold plate. The cooling unit includes a sample holder and a connecting column, and the connecting column is located at the bottom of the sample holder, and the connecting column is matched and fixed with the reference hole. Multiple circuit channels are arranged inside the heat sink cold plate, and the upper surface of the heat sink cold plate is covered with insulating material.

3. The biological sample freezing rack with zoned temperature control according to claim 1, characterized in that: The aperture size of the sample slot is 1-100 mm, the depth of the sample slot is 1-200 mm, and the number of sample holes in the sample slot is 1 or more.

4. The biological sample freezing rack with zoned temperature control according to claim 1, characterized in that: It also includes a thermal connector, and the cooling unit is connected and fixed to the heat sink through the thermal connector.

5. A biological sample freezing rack with zoned temperature control according to claim 4, characterized in that: The thermal connector is made of sapphire and has a thickness of 0.1-20 mm.

6. The biological sample freezing rack with zoned temperature control according to claim 4, characterized in that: The thermal connector includes a micro-expansion low-temperature thermal switch.

7. A programmed cooling device, characterized in that: It comprises a biological sample freezing rack with zoned temperature control, a sample freezing rack shell and a refrigeration unit as described in any one of claims 1 to 6; the refrigeration unit comprises a refrigeration source, and the refrigeration source is located in the refrigeration unit.

8. A programmed cooling device according to claim 7, characterized in that: The cooling source is a refrigerator; the refrigerator comprises a cold head connected to the lower surface of the heat sink cold plate.

9. A programmed cooling device according to claim 7, characterized in that: The cooling source is a refrigerant; the cooling unit comprises a Dewar vessel, the refrigerant is loaded in the Dewar vessel, and the opening of the Dewar vessel is coupled to the lower surface of the heat sink cold plate.

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