KR20230132238A - Cryogenic refrigerator for controlling individually 1st stage and 2nd stage - Google Patents

Abstract

A cryogenic freezer that individually controls the first stage unit and the second stage unit includes a cylinder including a first stage cylinder with the first stage unit installed and a second stage cylinder with the second stage unit installed, and a first stage displacer that reciprocates within the first stage cylinder. and a displacer including a two-stage displacer reciprocating within the two-stage cylinder and a control device for controlling at least one of the first stage displacer or the second stage displacer, the first stage displacer and the second stage displacer. However, the drive shafts of the displacers are different from each other, and the first stage unit and the second stage unit are individually controlled by the different drive shafts.

Description

Cryogenic refrigerator that individually controls the 1st stage and the 2nd stage {CRYOGENIC REFRIGERATOR FOR CONTROLLING INDIVIDUALLY 1ST STAGE AND 2ND STAGE}

The present invention relates to a cryogenic refrigerator that individually controls the first stage unit and the second stage unit.

Cryogenic cooling is widely used in many industrial fields, such as semiconductor manufacturing and testing fields. Here, ultra-low temperature may mean a temperature of -200°C or lower, and the cooling process to obtain ultra-low temperature typically includes a compressor, condenser, expander, and evaporator, and the refrigerant is evaporated in the evaporator to create a cryogenic environment. .

In relation to technology for creating such an ultra-low temperature environment, Korean Patent Publication No. 2020-0079062, a prior art, discloses an ultra-low temperature freezer.

To create an ultra-low temperature environment, a GM (Gifford McMahon) refrigerator, a refrigerator for high vacuum cryopumps, is mainly used. Hereinafter, the configuration of creating a cryogenic environment using a GM refrigerator will be described with reference to FIG. 1.

1 is an exemplary diagram showing a conventional ultra-low temperature refrigerator. Referring to FIG. 1, a conventional cryogenic freezer 1 includes a cylinder 100, a first stage unit 110, a second stage unit 120, and a control device 140.

In the conventional cryogenic freezer 1, the displacer 130 of the first stage unit 110 and the second stage unit 120 reciprocates within the cylinder 100 to expand the helium (He) gas therein. A cryogenic environment is created using the cooling principle.

However, in the conventional cryogenic refrigerator 1, the displacers 130 of the first stage unit 110 and the second stage unit 120 are connected to the same drive unit and drive shaft 150, so that one control device 140 It is controlled at the same number of revolutions per minute.

For this reason, the desired cooling performance may be different for each stage of the conventional cryogenic refrigerator 1, but as the conventional cryogenic refrigerator 1 is configured to have a single drive shaft 150, the control device 140 There was a problem in that it was difficult to control the desired cooling performance for each stage part of each stage because it was controlled with the same up and down reciprocating cycle.

In addition, in the conventional cryogenic refrigerator 1, the first stage unit 110 and the second stage unit 120 are configured with the same drive shaft 150 and are controlled at the same number of revolutions per minute, so that the fluid generated in a cryogenic environment It had the disadvantage of not being able to selectively exhaust.

A display including a first-stage cylinder with a first-stage stage installed and a second-stage cylinder with a second-stage stage installed, a first-stage displacer reciprocating within the first-stage cylinder, and a second-stage displacer reciprocating within the second-stage cylinder. An object is to provide a cryogenic freezer including a control device for controlling at least one of a first-stage displacer and a first-stage displacer.

An object is to provide a cryogenic refrigerator in which the drive shafts of the first-stage displacer and the second-stage displacer are different from each other, and the first stage unit and the second stage unit are individually controlled by the different drive shafts.

However, the technical challenges that this embodiment aims to achieve are not limited to the technical challenges described above, and other technical challenges may exist.

As a means to achieve the above-mentioned technical problem, an embodiment of the present invention includes a cylinder including a first-stage cylinder with a first-stage stage installed and a second-stage cylinder with a second-stage stage installed, and a cylinder that reciprocates within the first-stage cylinder. A displacer including a first-stage displacer and a second-stage displacer reciprocating within the second-stage cylinder, and a control device for controlling at least one of the first-stage displacer or the second-stage displacer, the first-stage display It is possible to provide a cryogenic refrigerator in which the driving shafts of the displacer and the second stage displacer are different from each other, and the first stage unit and the second stage unit are individually controlled by the different drive shafts.

According to one embodiment, the control device selects one of the first stage displacer and the second stage displacer to exhaust fluid generated in the cooling process, and controls the operation of the selected displacer. A cryogenic freezer can be provided.

According to one embodiment, the control device selects the first stage displacer to exhaust moisture generated in the cooling process and selects the second stage displacer to exhaust specific gas generated in the cooling process. A cryogenic freezer can be provided.

According to one embodiment, the temperature of the first stage part may be 80K or less, and the temperature of the second stage part may be 20K or less.

According to one embodiment, the control device controls the speed per minute of the first stage displacer based on whether the first exhaust speed corresponding to the condensation speed of moisture condensed in the baffle connected to the first stage unit is the target exhaust speed. A cryogenic refrigerator whose rotation speed is controlled can be provided.

According to one embodiment, the control device controls the second stage based on whether the second exhaust speed corresponding to the condensation speed of the first specific gas condensed in the array connected to the second stage unit is the target exhaust speed. A cryogenic refrigerator that controls the number of revolutions per minute of the displacer can be provided.

According to one embodiment, the control device determines the target exhaust speed based on whether the third exhaust speed corresponding to the condensation speed of the second specific gas condensed in the charcoal attached to the array of the two-stage stage unit is the target exhaust speed. It is possible to provide a cryogenic freezer that further controls the number of revolutions per minute of the two-stage displacer.

The above-described means for solving the problem are merely illustrative and should not be construed as limiting the present invention. In addition to the exemplary embodiments described above, there may be additional embodiments described in the drawings and detailed description of the invention.

According to any one of the above-described means for solving the problems of the present invention, a first-stage displacer reciprocates within a first-stage cylinder on which a first-stage stage unit is installed or a two-stage displacer reciprocates within a second-stage cylinder on which a second-stage stage unit is installed. By controlling at least one of the cryogenic refrigerators, it is possible to provide a cryogenic refrigerator that allows individual control of the first stage portion and the second stage portion of the cryogenic refrigerator.

It is possible to provide a cryogenic freezer that allows efficient process operation by controlling the vacuum level required by the vacuum area in the process in real time.

1 is an exemplary diagram showing a conventional ultra-low temperature refrigerator.
Figure 2 is an exemplary diagram showing a cryogenic refrigerator according to an embodiment of the present invention.
Figure 3 is an exemplary diagram for explaining a process of exhausting fluid through individual control of the first stage unit and the second stage unit according to an embodiment of the present invention.

Below, with reference to the attached drawings, embodiments of the present invention will be described in detail so that those skilled in the art can easily implement the present invention. However, the present invention may be implemented in many different forms and is not limited to the embodiments described herein. In order to clearly explain the present invention in the drawings, parts that are not related to the description are omitted, and similar parts are given similar reference numerals throughout the specification.

Throughout the specification, when a part is said to be "connected" to another part, this includes not only the case where it is "directly connected," but also the case where it is "electrically connected" with another element in between. . In addition, when a part is said to "include" a certain component, this does not mean excluding other components unless specifically stated to the contrary, but may further include other components, and one or more other features. It should be understood that it does not exclude in advance the presence or addition of numbers, steps, operations, components, parts, or combinations thereof.

In this specification, 'part' includes a unit realized by hardware, a unit realized by software, and a unit realized using both. Additionally, one unit may be realized using two or more pieces of hardware, and two or more units may be realized using one piece of hardware.

In this specification, some of the operations or functions described as being performed by a terminal or device may instead be performed on a server connected to the terminal or device. Likewise, some of the operations or functions described as being performed by the server may also be performed on a terminal or device connected to the server.

Hereinafter, an embodiment of the present invention will be described in detail with reference to the attached drawings.

Figure 2 is an exemplary diagram showing a cryogenic refrigerator according to an embodiment of the present invention. Referring to FIG. 2, the cryogenic freezer 2 may include a cylinder 200, a first stage unit 210, a second stage unit 220, displacers 230, 235, and a control device 240. there is. The cryogenic refrigerator 2 according to an embodiment of the present invention may be a GM (Gifford-McMahon) refrigerator equipped with a first stage unit 210 and a second stage unit 220.

When helium refrigerant gas flows into the cylinder 200, the first-stage displacer 230 and the second-stage displacer 235 reciprocate up and down within the cylinder 200, so that the refrigerant gas expands adiabatically. can be cooled through

This cylinder 200 may include a first-stage cylinder 202 and a second-stage cylinder 201. Here, the first stage cylinder 202 may be located at the lower end of the cylinder 200, and the second stage cylinder 201 may be located at the upper end of the cylinder 200.

A first stage unit 210 may be installed in the first stage cylinder 202. Here, the temperature of the first stage unit 210 may be, for example, 80K or less.

A second stage unit 220 may be installed in the second stage cylinder 201. Here, the temperature of the second stage unit 220 may be, for example, 20K or less.

The displacers 230 and 235 may be piston-type elements that reciprocate within the cylinder 200 of the cryogenic freezer 2. For example, the displacers 230 and 235 can compress and expand helium refrigerant gas by reciprocating the cylinder 200 up and down. Here, the helium refrigerant gas can be cooled through adiabatic expansion.

These displacers 230 and 235 may include a first-stage displacer 230 and a second-stage displacer 235.

The first-stage displacer 230 can reciprocate within the first-stage cylinder 202. Here, the first-stage displacer 230 reciprocates within the first-stage cylinder 202, so that the first-stage stage unit 210 can be cooled to 80K or less.

The second-stage displacer 235 can reciprocate within the second-stage cylinder 201. Here, the second-stage displacer 235 reciprocates within the second-stage cylinder 201, so that the second-stage stage unit 220 can be cooled to 20K or less.

Here, the drive shafts of the first-stage displacer 230 and the second-stage displacer 235 may be different from each other. For example, the drive shaft 250 of the first-stage displacer 230 and the drive shaft 255 of the second-stage displacer 235 may have different drive shafts. For example, the first-stage displacer 230 may have a drive shaft 250 located from the lower end of the first-stage cylinder 202 to the lower end of the first-stage displacer 230, and the second-stage displacer 235 may have It may have a drive shaft 255 located from the lower end of the first-stage displacer 230 through the first-stage displacer 230 to the lower end of the second-stage displacer 235.

For another example, the drive shaft 250 of the first-stage displacer 230 and the drive shaft 255 of the second-stage displacer 235 may have different widths. For example, the width of the drive shaft 250 connected to the first-stage displacer 230 may be wider than the width of the drive shaft 255 connected to the second-stage displacer 235.

The control device 240 may control at least one of the first-stage displacer 230 or the second-stage displacer 235. Here, the control device 240 has different drive axes of the first-stage displacer 230 and the second-stage displacer 235, and thus the first-stage stage unit 210 and the second-stage stage unit 220 are operated by different drive shafts. can be individually controlled.

This control device 240 may be composed of a single control device module, or may be composed of a plurality of control devices so as to control the first-stage displacer 230 and the second-stage displacer 235, respectively.

In the present invention, the first stage displacer 230 and the second stage displacer 235 of the cryogenic freezer 2 are connected to different driving units and driving shafts, so that the same or different up and down reciprocation is performed through at least one control device 240. By controlling the first-stage displacer 230 and the second-stage displacer 235 to be driven by the exercise cycle, the stage portion of each stage can be controlled individually, providing the advantage of providing improved cooling performance.

That is, the present invention includes a plurality of independent drive shafts corresponding to the stage parts of each stage, so that both the first stage stage part 210 and the second stage part 220 can be driven and controlled independently, so that each stage The cooling performance of the stage part can be controlled independently.

The control device 240 selects one of the first stage unit 210 and the second stage unit 220 to exhaust the fluid generated in the cooling process and controls the operation of the selected displacer. there is.

This is to independently control each displacer for each stage of the cryogenic freezer 2 having the first stage displacer 230 and the second stage displacer 235 that operate independently. For example, the control device 240 may use one of the first stage displacer 230 or the second stage displacer 235 to control the temperature of at least one of the first stage unit 210 or the second stage unit 220. At least one revolution per minute (RPM) can be controlled. For another example, the control device 240 may control the reciprocating speed of the displacer with respect to the stage unit of each stage.

The control device 240 can control temperature and pressure to independently control and monitor the first stage unit 210 and the second stage unit 220.

The process of controlling the operation of the displacer by selecting one of the first stage unit 210 and the second stage unit 220 to exhaust the fluid generated in this cooling process will be described in detail with reference to FIG. 3. .

Figure 3 is an exemplary diagram for explaining a process of exhausting fluid through individual control of the first stage unit and the second stage unit according to an embodiment of the present invention.

When the vacuum area 300 is formed through the first stage unit 210 and the second stage unit 220 of the cryogenic refrigerator 2, the control device 240 operates in the first stage to exhaust moisture generated in the cooling process. The stage unit 210 can be selected, and the two-stage stage unit 220 can be selected to exhaust a specific gas generated in the cooling process.

Referring to FIG. 3, the baffle 310 connected to the first stage unit 210 performs the function of condensing moisture and exhausting it.

The control device 240 controls the condensation rate of the moisture condensed in the baffle 310 connected to the first stage unit 210 and the per minute of the first stage displacer 230 based on whether the first exhaust speed corresponding to the target exhaust speed is the target exhaust speed. The number of rotations can be controlled. For example, when the first exhaust speed is lower than the target exhaust speed, the control device 240 may increase the number of revolutions per minute of the first stage displacer 230 to improve the first exhaust speed. For another example, when the first exhaust speed is higher than the target exhaust speed, the control device 240 may control the first exhaust speed to become the target exhaust speed by reducing the number of revolutions per minute of the first stage displacer 230. there is.

The array 320 connected to the second stage unit 220 performs the function of condensing and exhausting a first specific gas such as nitrogen or argon.

The control device 240 operates a two-stage displacer ( 235) revolutions per minute can be controlled. For example, when the second exhaust speed is lower than the target exhaust speed, the control device 240 may improve the second exhaust speed by increasing the number of revolutions per minute of the second stage displacer 230. For another example, when the second exhaust speed is higher than the target exhaust speed, the control device 240 may control the second exhaust speed to become the target exhaust speed by reducing the number of revolutions per minute of the second stage displacer 235. there is.

Charcoal (330) attached to the array 320 connected to the second stage unit 220 performs the function of adsorbing and exhausting a second specific gas such as hydrogen and xenon.

The control device 240 is based on whether the third exhaust speed corresponding to the condensation speed of the second specific gas condensed in the charcoal 330 attached to the array 320 of the second stage unit 220 is the target exhaust speed. Thus, the number of revolutions per minute of the two-stage displacer 235 can be further controlled. For example, when the third exhaust speed is lower than the target exhaust speed, the control device 240 increases the number of revolutions per minute of the second stage displacer 230 to a number of revolutions per minute appropriate for the exhaust rate of the second specific gas. 3 Exhaust speed can be improved. For another example, when the third exhaust speed is higher than the target exhaust speed, the control device 240 reduces the revolutions per minute of the second stage displacer 235 to a revolutions per minute suitable for the exhaust speed of the second specific gas. The third exhaust speed can be further controlled to become the target exhaust speed.

In general, in the case of a cryogenic refrigeration pump having the same area of the baffle 310 and the same area of the array 320, the exhaust speed may be affected by the temperature of the cryogenic refrigerator 2. Here, the lower the temperature of the cryogenic refrigerator 2, the higher the exhaust speed, and conversely, the higher the temperature of the cryogenic refrigerator 2, the lower the exhaust speed.

Therefore, when the displacer of the cryogenic freezer 2 performs up and down reciprocation, the number of revolutions per minute of the displacer is equal to the number of revolutions per minute of the motor connected to the drive shaft of the displacer and the can, etc., so the higher the number of revolutions per minute, the faster the cryogenic freezer The temperature of (2) can be lowered.

In the conventional cryogenic freezer (1), the displacers (130) of the first stage unit (110) and the second stage unit (120) are configured with the same drive shaft and are controlled at the same number of revolutions per minute. ) had the disadvantage that the moisture exhaust rate of the first stage unit 110 and the specific gas exhaust speed of the second stage unit 120 were not independently controlled.

In addition, in the case of the conventional cryogenic refrigerator 1, the first stage unit 110 and the second stage unit 120 are driven simultaneously, so it is not possible to select and exhaust specific gases such as moisture and argon.

However, in the present invention, when it is desired to exhaust only moisture, only the first stage unit 210 is driven, and when it is desired to exhaust a specific gas such as argon, only the second stage unit 220 is driven to selectively exhaust moisture or a specific gas. It is possible to provide the effect of independently controlling the first stage unit 210 and the second stage unit 220 to exhaust air.

The description of the present invention described above is for illustrative purposes, and those skilled in the art will understand that the present invention can be easily modified into other specific forms without changing the technical idea or essential features of the present invention. will be. Therefore, the embodiments described above should be understood in all respects as illustrative and not restrictive. For example, each component described as single may be implemented in a distributed manner, and similarly, components described as distributed may also be implemented in a combined form.

The scope of the present invention is indicated by the claims described below rather than the detailed description above, and all changes or modified forms derived from the meaning and scope of the claims and their equivalent concepts should be construed as being included in the scope of the present invention. do.

2: Ultra-low temperature freezer
200: cylinder
201: Two-stage cylinder
202: 1st stage cylinder
210: 1st stage part
220: 2nd stage part
230: 1st stage displacer
235: Two-stage displacer
240: control device
250, 255: Drive shaft

Claims (8)

In a cryogenic freezer that individually controls the first stage and the second stage,
A cylinder including a first-stage cylinder with a first-stage stage installed and a second-stage cylinder with a second-stage stage installed;
a displacer including a first stage displacer reciprocating within the first stage cylinder and a second stage displacer reciprocating within the second stage cylinder; and
A control device that controls at least one of the first stage displacer or the second stage displacer
Including,
The drive shafts of the first stage displacer and the second stage displacer are different from each other,
A cryogenic refrigerator in which the first stage unit and the second stage unit are individually controlled by the different drive shafts.
According to claim 1,
The control device selects one of the first stage displacer and the second stage displacer to exhaust fluid generated in the cooling process,
A cryogenic refrigerator that controls the operation of any one of the selected displacers.
According to claim 2,
The control device selects the first stage displacer to exhaust moisture generated in the cooling process,
A cryogenic refrigerator that selects the two-stage displacer to exhaust a specific gas generated in the cooling process.
According to claim 1,
The control device controls the number of revolutions per minute of at least one of the first stage displacer or the second stage displacer to control the temperature of at least one of the first stage part or the second stage part. .
According to claim 4,
The temperature of the first stage part is 80K or less,
A cryogenic refrigerator, wherein the temperature of the second stage portion is 20K or less.
According to claim 4,
The control device controls the number of revolutions per minute of the first stage displacer based on whether the first exhaust speed corresponding to the condensation speed of moisture condensed in the baffle connected to the first stage unit is the target exhaust speed. In, ultra-low temperature freezer.
According to claim 4,
The control device controls the number of revolutions per minute of the second stage displacer based on whether the second exhaust speed corresponding to the condensation speed of the first specific gas condensed in the array connected to the second stage unit is the target exhaust speed. A cryogenic freezer that controls a.
According to claim 7,
The control device controls the speed per minute of the two-stage displacer based on whether the third exhaust speed corresponding to the condensation speed of the second specific gas condensed in the charcoal attached to the array of the two-stage stage unit is the target exhaust speed. A cryogenic freezer that further controls the number of rotations.