WO2015178659A1

WO2015178659A1 - Ultra low temperature freezer

Info

Publication number: WO2015178659A1
Application number: PCT/KR2015/004994
Authority: WO
Inventors: 윤근진
Original assignee: 주식회사 지엠에스
Priority date: 2014-05-21
Filing date: 2015-05-19
Publication date: 2015-11-26
Also published as: CN106461286A; KR101438155B1

Abstract

Disclosed is an ultra low temperature freezer in which a double pipe is formed so that the volume of the double pipe for performing heat exchange between a refrigerant discharged from a condenser and a refrigerant discharged from an evaporator is 70% to 130% relative to the volume of an evaporation pipe, thereby rapidly lowering the temperature of the refrigerants to the ultra low temperature as the cooling cycle of the refrigerants is repeated. To this end, the present invention provides an ultra low temperature freezer comprising an evaporator having an evaporation pipe, a compressor, an expansion pipe, and a condenser, the freezer further comprising a first refrigerant pipe which is provided between the condenser and the expansion pipe and which is connected between the condenser and the expansion pipe, and a second refrigerant pipe which receives the first refrigerant pipe therein to form a double pipe and which is connected between the evaporator and the compressor, wherein the volume difference between the volume of the second refrigerant pipe and the volume of the first refrigerant pipe may be 70% to 130% relative to the volume of the evaporation pipe.

Description

Cryogenic Freezer

The present invention relates to an ultra-low temperature freezer, and more particularly, does not use a separate refrigerant such as a cryogenic refrigerant, and rapidly freezes to a temperature below minus 80 degrees even in a refrigerator having a conventional structure by adjusting the volume of a double tube. A possible cryogenic freezer is provided.

The refrigerator has a compressor, a condenser, an expander and an evaporator, and is configured to cool the freezer using a cooling cycle of compression-condensation-expansion-evaporation.

The cooling cycle includes a compression cycle for compressing a gaseous refrigerant at high temperature and high pressure through operation of a compressor, a condensation cycle for condensing and liquefying gas compressed at high temperature and pressure, an expansion cycle for lowering the pressure of the condensed gas, and a pressure. It consists of an evaporation cycle that lowers the temperature of the freezer compartment by vaporizing the lowered refrigerant.

In the refrigerator constituted by the above-mentioned cooling cycle, a double pipe is connected between the condenser and the expander, and the cooling efficiency of the refrigerator is improved by cooling the refrigerant discharged from the condenser with a low temperature / low pressure refrigerant discharged from the evaporator. In this case, the double tube may include a first refrigerant tube and a first refrigerant tube directed from the condenser to the expander, and may be configured as a second refrigerant tube connected between the evaporator and the compressor. By using the double tube to sufficiently cool the refrigerant discharged from the condenser, it is possible to improve the cooling effect of the cooling cycle consisting of the compressor-condenser-expander-evaporator.

As an example of a refrigerator using a double tube, Korean Patent No. 10-0836824 has been proposed. Patent No. 10-0836824 uses dry ice (carbon dioxide) as a refrigerant, and in order to minimize volume increase by the accumulator, a first flow passage connected to the outlet side of the gas cooler and a second passage connected to the outlet side of the evaporator are provided. Let the flow paths exchange with each other. At this time, the patent 10-0836824 is to implement the refrigerator main body compactly without mounting an accumulator by allowing the first passage to flow downward of the main body. However, as shown in FIG. 5 of Patent No. 10-0836824, Patent No. 10-0836824 constitutes a double tube in a stacked coil shape, and thus the volume of the double tube itself has a limitation in implementing a refrigerator in a compact manner. It should be used as a refrigerant, and the accumulator was removed by lowering the refrigerant flow in the double tube rather than increasing the cooling efficiency by using the double tube, and technical considerations for rapid freezing were excluded.

It is an object of the present invention to set the refrigerant discharged from the condenser and the refrigerant discharged from the evaporator to 70% to 130% compared to the volume evaporation tube of the double tube performing heat exchange, so that the refrigerant temperature is rapidly set as the cooling cycle of the refrigerant is repeated. It is to provide a cryogenic freezer to be lowered.

In order to achieve the above object, the cryogenic freezer according to the embodiment of the present invention may be configured to include an evaporator, a compressor, an expansion tube, a condenser and a double tube in which the evaporation tube is accommodated. At this time, the double tube is provided between the condenser and the expansion tube, the first refrigerant pipe connected between the condenser and the expansion tube and the first refrigerant pipe is stored therein to form a double tube, the first connection between the evaporator and the compressor The main point of the present invention is to include a second refrigerant pipe, and the difference between the volume of the second refrigerant pipe and the volume of the first refrigerant pipe as the volume of the evaporation pipe is 70% to 130%.

In order to achieve the above object, the cryogenic freezer according to the embodiment of the present invention may be configured to include an evaporator, a compressor, an expansion tube, a condenser and a double tube in which the evaporation tube is accommodated. At this time, the double tube is provided between the condenser and the expansion tube, the first refrigerant pipe connected between the condenser and the expansion tube and the first refrigerant pipe is stored therein to form a double tube, the first connection between the evaporator and the compressor It includes two refrigerant tubes, the main point is that the length of the second refrigerant tube or the first refrigerant tube relative to the length of the evaporation tube is 70% to 130%.

In order to achieve the above object, the cryogenic freezer according to the embodiment of the present invention may be configured to include an evaporator, a compressor, an expansion tube, a condenser and a double tube in which the evaporation tube is accommodated. At this time, the double pipe is formed inside the first refrigerant pipe to form a double pipe, and includes a second refrigerant pipe connected between the evaporator and the compressor, the refrigerant movement time in the evaporation tube is the first travel time, When the refrigerant movement time in the second refrigerant pipe is the second movement time, the main point of the length of the second refrigerant tube is set so that the second movement time is 70% to 130% of the first movement time. .

According to the present invention, by forming a double tube so that the volume of the double tube in which the refrigerant discharged from the condenser and the refrigerant discharged from the evaporator performs heat exchange becomes 70% to 130 relative to the volume of the evaporation tube, the cooling cycle of the refrigerant is repeated. The temperature can be rapidly lowered to cryogenic temperatures.

1 is a perspective view of a cryogenic freezer according to an embodiment of the present invention.

Figure 2 shows a reference view for explaining the refrigeration cycle of the cryogenic freezer according to an embodiment of the present invention.

3 and 4 show reference views for an example of the double tube shown in FIG. 2.

5 and 6 show reference drawings for a double tube disposed between the body and the body and a structure in which the double tube is molded.

7 shows a reference drawing for a method for obtaining the volume of a double tube according to an embodiment.

8 is a reference view for explaining a refrigeration cycle of the cryogenic freezer according to another embodiment of the present invention.

The evaporator referred to herein is composed of an evaporator tube, and the evaporator and the evaporator tube may be used interchangeably in the present specification.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. In this case, the same components in the accompanying drawings are to be noted with the same reference numerals as possible. In addition, detailed descriptions of well-known functions and configurations that may blur the gist of the present invention will be omitted. For the same reason, in the accompanying drawings, some components are exaggerated, omitted or schematically illustrated.

1 is a perspective view of a cryogenic freezer 100 according to an embodiment of the present invention, Figure 2 shows a reference diagram for explaining the refrigeration cycle of the cryogenic freezer 100 according to an embodiment of the present invention. do.

1 and 2 together, the cryogenic freezer 100 according to the embodiment includes a body 103 and a freezer compartment 101, the freezer compartment 101 can accommodate living tissue, blood, cell tissue have. The freezer compartment 101 may be provided with a transparent window so that it can be seen from the outside. In this case, the transparent window may be composed of a double glass having a vacuum layer in view of the freezer compartment 101 temperature of −80 degrees.

The condenser 120 and the compressor 110 may be stored at the lower end of the cryogenic freezer 100, and the double tube 140 may be stored at the rear surface thereof. Here, the double tube 140 may be configured such that the second refrigerant tube 142 accommodates the first refrigerant tube 141. The first refrigerant tube 141 may be connected to the expansion tube 150 from the filter drier 130, and the second refrigerant tube 142 may be connected between the evaporator 160 and the compressor 110. That is, the first refrigerant pipe 141 is used to cool the refrigerant from the filter drier 130 toward the expansion pipe 150, and the second refrigerant pipe 142 pre-cools the refrigerant of the first refrigerant pipe 141. After cooling, the cooled refrigerant may be discharged to the expansion tube 130.

The filter drier 130 may filter the moisture or the foreign matter from the refrigerant discharged from the condenser 120, and then provide the refrigerant to the first refrigerant pipe 141 of the double pipe 140.

Here, in the double tube 140, the first refrigerant tube 141 directs the refrigerant to the expansion tube 150 in the filter drier 130, the second refrigerant tube 142 is the refrigerant in the evaporator 160, the compressor Face (110). That is, the refrigerant flowing in the first refrigerant pipe 141 and the refrigerant flowing in the second refrigerant pipe 142 are moved in opposite directions to each other, and the first refrigerant pipe 141 and the second refrigerant pipe ( Heat exchange of 142 can be effected effectively.

This double tube 140 may be disposed on the back side of the housing 103 and then molded by foamed urethane. Foam urethane is a resin having a myriad of air layers therein, and is applied between the freezing chamber 101 and the main body 103 to insulate the cryogenic freezer 100 according to the embodiment, wherein the main body 103 and the freezing chamber ( The double tube 140 having a planar coil shape may be molded between the 101 parts.

The double tube 140 may be formed in a planar coil type in order to minimize the volume and to make it compact. Double tube 140 may have a coil shape toward the center in the circumferential surface. Accordingly, when the double tube 140 is disposed on the rear surface of the main body 103 and then molded by the foamed urethane, the molding is performed by the urethane foam on the rear side of the main body 103 without significantly increasing the thickness of the main body 103. Can be. This will be described later.

The refrigerant discharged from the filter drier 130 is further cooled by the second refrigerant pipe 142 in the first refrigerant pipe 141 of the double pipe 140 and then provided to the expander 150, wherein the expander ( The refrigerant applied to 150 may be sufficiently overcooled. The supercooled coolant is expanded in the expansion tube 150 to become a low-temperature / low-pressure gaseous coolant, and may be lowered to a sufficiently low temperature when it flows into the freezing compartment 101.

The evaporator 160 absorbs the latent heat of the freezer compartment 101 to allow the refrigerant to be phase-changed into a gas-> liquid state. At this time, the evaporator 160 has a form of an evaporation tube provided in the evaporation chamber 101, the volume of the double tube 140 may have a range of 1: 1 or 70% to 130% of the volume of the evaporation tube. have.

here,

1) The volume of the evaporation tube means the volume calculated based on the inner diameter of the evaporation tube,

2) The volume of the double tube 140 may mean [the volume of the second refrigerant tube 142-the volume of the first refrigerant tube 141]. Hereinafter, [the volume of the second refrigerant pipe 142-the volume of the first refrigerant pipe 141] is defined as "difference volume".

At this time, the volume of the second refrigerant pipe 142 corresponds to the volume based on the inner diameter of the second refrigerant pipe 142,

The volume of the first refrigerant pipe 141 may correspond to a volume based on the outer diameter of the first refrigerant pipe 141.

Here, the volume of the second refrigerant pipe 142 refers to an internal volume through which the refrigerant can flow purely inside the second refrigerant pipe 142.

When the vehicle volume = the evaporation tube volume, the refrigerant discharged from the evaporator tube toward the compressor 110 cools the liquid refrigerant from the filter drier 130 toward the expansion tube 150 and the first refrigerant tube 141. The refrigerant from the filter drier 130 to the expansion tube 150 may be cooled in the condenser 120 and then cooled again to be provided to the expansion tube 150. The refrigerant vaporized in the expansion tube (150) is in a low temperature / low pressure state, and absorbs the latent heat of the freezer compartment (101) in the evaporator (160) and is provided to the second refrigerant tube (142). In the second refrigerant pipe 142, the refrigerant may exchange heat with the first refrigerant pipe 141 to absorb the heat of the refrigerant flowing through the first refrigerant pipe 141 and return it to the compressor 110. Accordingly, the compressor 110 may receive the refrigerant heated by the first refrigerant pipe 141 and rapidly compress the refrigerant in a high temperature / high pressure state to provide the refrigerant to the condenser 120. As such, since the refrigerant returned from the second refrigerant pipe 142 to the compressor 110 is sufficiently heated, the efficiency of converting the refrigerant into a high temperature / high pressure state by compressing the refrigerant in the compressor 110 may be improved. The improvement in efficiency means that the cooling cycle can be completed more quickly and the temperature of the freezer compartment 101 can be lowered.

In this case, the volume of the second refrigerant pipe 142 may be formed to be equal to 1: 1 with the volume of the evaporator tube constituting the evaporator 160, or the volume may be increased or decreased according to the target temperature.

The volume of the evaporator tube is proportional to the cooling capacity of lowering the temperature of the freezer compartment 101, and forms the volume of the second refrigerant tube 142 in accordance with the cooling capacity of the evaporator tube, and the velocity of the refrigerant from node A to node D. Assuming that is constant, it can be seen that the refrigerant flowing through the evaporation tube is heated in the second refrigerant tube 142 of the same volume. Accordingly, the refrigerant from the evaporator tube toward the compressor 110 is sufficiently preheated in the second refrigerant tube 142 and applied to the compressor 110, and the compressor 110 compresses the preheated refrigerant and provides the condenser 120. can do. This preheating cycle is performed by the preheating of the refrigerant every time the cooling cycle for the compressor 110-condenser 120-filter drier 130, double pipe 140-expander 150-evaporator 160 is repeated. It can accumulate and improve the efficiency of a cooling cycle.

That is, the freezing compartment 101 can be cooled to ultra low temperature quickly within a short time. For example, when the diameter of the evaporator tube constituting the evaporator 160 is 7mm, the first refrigerant tube 141 constituting the double tube 140 has an outer diameter of 4mm, the inner diameter of the second refrigerant tube 142 is 8mm. Assuming that (the outer diameter is 9 mm), the volume of the evaporation tube can be calculated as (radius) ² x π xh (length), and can be calculated as "12.25 π xh".

At this time, the volume of the first refrigerant pipe 141 is "4Π xh", the volume of the second refrigerant pipe 142 is calculated as "16Π xh", the car volume is "16Π xh"-"4Π xh" = It can be calculated as "12? Xh". If it is assumed that the length of the evaporation tube and the length of the second refrigerant tube 142 is the same, the volume ratio of the second refrigerant tube 142 (or the first refrigerant tube 141) to the volume of the evaporation tube,

12 / 12.5 = 96%.

On the other hand, when the evaporation tube and the second refrigerant tube 142 (or the first refrigerant tube 141) according to the volume ratio described above have a similar volume,

The temperature of the refrigerant flowing into the expansion tube 150 is increased by the first refrigerant tube 141 and the temperature of the refrigerant from the evaporation tube to the compressor 110 decreases through the second refrigerant tube 142, thereby expanding. The expansion temperature difference ΔT defined by the temperature difference between the temperature of the refrigerant expanded in the pipe 150 and the external air temperature of the refrigerating chamber 101 decreases.

Reduction of the expansion temperature difference ΔT may be such that the temperature of the refrigerant flowing through the evaporation tube is not lowered below -100 ° C., and the temperature of the refrigerant is −70 ° C. to −80 ° C. That is, the cryogenic freezer according to the embodiment can quickly reach a certain temperature range (-70 ℃ to -80 ℃), and does not simply lower or raise the temperature continuously, but a predetermined temperature range (-70 ℃ to -80 Can be reached quickly). The medical freezer according to the embodiment allows cells, DNA, blood and other materials to be stored in a rapid and constant temperature range to be tested or preserved.

3 and 4 illustrate a reference diagram of an example of the double tube 140 shown in FIG. 2. 3 and 4 will be referred to together with FIG. 1.

Referring to FIG. 3, the double pipe 140 according to the embodiment has one surface of the second refrigerant pipe 142 having the shape of inserting the first refrigerant pipe 141 toward the center from the circumferential surface thereof. It can be seen that it has a flat coil shape. This structure is such that when the double tube 140 according to the embodiment is disposed on the rear surface of the main body 103, it is attached to the rear surface of the main body 103 in a planar coil shape, so as not to increase the thickness of the main body 103. Can be. That is, the ultra-low temperature freezer according to the embodiment may be more compact and slim. One side of the double tube 140 illustrated in FIG. 3 may be connected to the filter drier 130, and the other side thereof may protrude in the direction D4 from the center thereof and may be connected to the expansion tube 150.

In FIG. 4, the double tube 140 may be in close contact with the rear surface of the body 103-1 to expose the planar concentric circle structure externally. In this state, when the main body 103 is covered with the body 103-1 and a foamed urethane resin is applied between the main body 103 and the body 103-1, it may be molded. This will be described with reference to FIGS. 5 and 6 together.

First, FIG. 5 illustrates an example in which the double tube 140 is disposed on the body 103-1, and the double tube 140 is disposed in parallel with the exposed surface of the body 103-1 so that the body 103 is disposed. -1) can be arranged without increasing the thickness. FIG. 6 is a reference diagram illustrating an arrangement relationship between a body 103-1 and a body 103 on which the double tube 140 is disposed, and as shown in FIG. 6, the double tube 140 has a body 103. After the arrangement is made in -1), the region S1 between the body 103-1 and the body 103 may be filled with a heat insulating material such as urethane foam. In this embodiment, the foamed urethane is referred to as a heat insulating material filling the area (S1), but in addition to the heat insulating material of styrofoam, foam rubber and various other materials may be filled in the area (S1).

When the foamed urethane is filled in the area S1, the double tube 140 disposed on the body 103-1 may be molded together with the body 103 by the foamed urethane. Accordingly, the double tube 140 may be heat exchanged between the first refrigerant tube 141 and the second refrigerant tube 142 without being affected by the external temperature.

7 shows a reference view for a method of obtaining the volume of a double tube 140 according to an embodiment.

Referring to FIG. 7, the double tube 140 according to the embodiment calculates the volume of the first refrigerant tube 141 based on the outer diameter D2 of the first refrigerant tube 141, and the second refrigerant tube 142. ), The volume of the second refrigerant pipe 142 is calculated based on the inner diameter D2, and the volume difference, which is the difference between the volume of the first refrigerant pipe 141 and the volume of the second refrigerant pipe 142, is calculated by the second. It is possible to calculate the volume of the refrigerant flowing through the refrigerant pipe 142.

The volume of the circular pipe shape may be calculated as shown in Equation 1 below, and based on this, the volume of the first refrigerant pipe 141 and the volume and volume difference of the second refrigerant pipe 142 are calculated.

Where v is the volume of the cylinder, π represents the circumference, r is the radius of the cylinder, and h represents the length of the cylinder.

The volume of the first refrigerant pipe 141 is calculated with reference to Equation 1 as shown in Equation 2 below.

Here, v1 is the volume of the first refrigerant pipe 141, π represents the circumference, D1 is the radius of the first refrigerant pipe 141, H represents the length of the first refrigerant pipe 141.

Next, referring to Equation 1, the volume of the second refrigerant pipe 142 is calculated as shown in Equation 3 below.

Here, v2 is the volume of the second refrigerant tube 142, π represents the circumference, D2 represents the radius of the second refrigerant tube, H represents the length of the second refrigerant tube 142. At this time, D2 may mean the inner diameter radius of the second refrigerant pipe 142, which is calculated by calculating the volume difference between the internal volume of the second refrigerant pipe 142 and the external volume of the first refrigerant pipe 141, 2 is used to calculate the pure volume of the refrigerant pipe 142.

The difference volume can be calculated as V2-V1. The length may be adjusted so that the vehicle volume calculated according to Equation 1 to Equation 3 is 70% to 130% of the volume of the evaporation tube. When vehicle volume = evaporation tube volume, the refrigerant flowing through the evaporation tube can be sufficiently preheated, and if the vehicle volume is more than 100% of the volume of the evaporation tube, it can be further preheated. If the refrigeration temperature of the cryogenic freezer according to the embodiment does not need to be lowered to -80 degrees or less, the vehicle volume may be 70% to 100% relative to the evaporation tube volume, and on the contrary, the cryogenic freezer according to the embodiment When cooling to a temperature of 80 degrees or less may be 101% to 130%. That is, the ratio of the volume of the car to the volume of the evaporation tube may be determined according to how much the cryogenic freezer according to the embodiment lowers the temperature of the freezing compartment 101.

If the length of the evaporation tube and the length of the second refrigerant tube 142 are the same, this may mean that the volume of the evaporation tube and the difference volume of the second refrigerant tube 142 and the first refrigerant tube 141 are the same. Can be. In this case, in the cryogenic freezer 100 according to the embodiment, the length of the second refrigerant tube 142 may be 130% compared to 70% of the length of the evaporation tube.

Referring to FIG. 8, the refrigerating cycle of the cryogenic freezer according to the embodiment has a refrigerating cycle of compression-condensation-expansion-evaporation as described with reference to FIG. 2, and is partially omitted in the drawing, but similarly to FIG. 2. Corresponding to the cryogenic freezer having a compressor 110, a condenser 120, a filter drier 130, a double tube 140, an expansion tube 150, and an evaporator 160.

Accordingly, descriptions and illustrations of the compressor 110, the condenser 120, the filter drier 130, and the expansion tube 150, which are duplicated with those of FIG. 2, will be omitted. Make sure to apply mutatis mutandis

The characteristic of the present embodiment is that the second refrigerant tube by using the ratio of the movement time of the refrigerant to move the evaporation tube, and the time to move the second refrigerant tube 142, not the volume of the evaporation tube constituting the evaporator 160. After the refrigerant to move sufficiently absorbs heat, it is characterized in that it is provided to the compressor (100). As such, the refrigerant is heated to be returned to the compressor 100 so that when the refrigerant is compressed in the compressor 100, the refrigerant is switched to a high temperature / high pressure state in a short time to be provided to the condenser 120, and the refrigerant is condenser. As it moves through the expansion pipe 150 through the 120, the refrigerant is cooled in the first refrigerant pipe 141 so that the refrigerant is heated in the second refrigerant pipe 142, and overcooling is performed in the first refrigerant pipe 141. You can do that. When the heating and overcooling of the refrigerant is repeated, the cryogenic freezer according to the embodiment may drop the temperature of the freezing compartment 101 to -80 degrees or less within a short time. Here, the matters regarding the heating and overcooling of the refrigerant are not limited to FIG. 8 and may be applied to the whole embodiment.

The second movement time t2 of the refrigerant moving through the second refrigerant tube 142 may be 70% to 130% compared to the first movement time t1 of the refrigerant moving through the evaporation tube, and the performance of the condenser 120 may be reduced. Accordingly, the second movement time t2 relative to the first movement time t1 may be increased in the range of 70% to 130% or more.

On the other hand, the embodiments of the present invention disclosed in the specification and drawings are merely presented specific examples to easily explain the technical contents and help the understanding of the present invention, and are not intended to limit the scope of the present invention. It will be apparent to those skilled in the art that other modifications based on the technical idea of the present invention can be carried out in addition to the embodiments disclosed herein.

The present invention can contribute to the vitalization of the industry for storing, researching and manipulating blood and cell tissues, and for the genetic engineering industry, and, if applied to long-term storage of non-biological tissues such as articles or materials, to activate the freezing and storage business. Can also contribute.

Claims

In the cryogenic freezer having an evaporator, a compressor, an expansion tube and a condenser having an evaporation tube,

A first refrigerant pipe provided between the condenser and the expansion tube and connected between the condenser and the expansion tube; And

A second refrigerant pipe connected between the evaporator and the compressor to form a double pipe by accommodating the first refrigerant pipe therein;

Cryogenic cryogenic freezer, characterized in that the difference between the volume of the second refrigerant pipe and the volume of the first refrigerant pipe compared to the volume of the evaporation tube is 70% to 130%.
The method of claim 1,

The car volume is

A first volume calculated according to the outer diameter of the first refrigerant pipe,

Ultra-low temperature freezer, characterized in that the volume difference with respect to the second volume calculated according to the inner diameter of the second refrigerant pipe.
The method of claim 1,

The first refrigerant pipe and the second refrigerant pipe,

Ultra-low temperature freezer, characterized in that the direction of movement of the refrigerant is opposite to each other.
The method of claim 1,

It is provided between the first refrigerant pipe and the condenser,

Ultra-low temperature freezer, characterized in that it further comprises; Filter Dryer (Filter Dryer) for removing the moisture and foreign matter of the refrigerant discharged from the condenser.
The method of claim 1,

The second refrigerant tube,

Cryogenic freezer, characterized in that formed in the form of a coil in a planar face toward the center from the circumferential surface is protruded and connected to the expansion tube.
The method of claim 1,

The second refrigerant tube,

The cryogenic freezer having the same length as the evaporation tube, wherein the vehicle volume coincides with the internal diameter volume of the evaporation tube.
The method of claim 1,

The second refrigerant tube,

Cryogenic freezer, characterized in that molded by foamed urethane.
In the cryogenic freezer having an evaporator, a compressor, an expansion tube and a condenser having an evaporation tube,

A first refrigerant pipe provided between the condenser and the expansion tube and connected between the condenser and the expansion tube; And

A second refrigerant pipe connected between the evaporator and the compressor to form a double pipe by accommodating the first refrigerant pipe therein;

When the refrigerant movement time in the evaporation tube is a first movement time, and when the refrigerant movement time in the second refrigerant tube is a second movement time, the length of the second refrigerant tube is the second movement time. Ultra-low temperature freezer, characterized in that it is set to 70% to 130% compared to 1 travel time.
The method of claim 8,

The first refrigerant pipe and the second refrigerant pipe,

Ultra-low temperature freezer, characterized in that the direction of movement of the refrigerant is opposite to each other.
The method of claim 8,

It is provided between the first refrigerant pipe and the condenser,

Ultra-low temperature freezer, characterized in that it further comprises; Filter Dryer (Filter Dryer) for removing the moisture and foreign matter of the refrigerant discharged from the condenser.
The method of claim 8,

The second refrigerant tube,

Cryogenic freezer, characterized in that formed in the form of a coil in a planar face toward the center from the circumferential surface is protruded and connected to the expansion tube.