CN115727563A - GM refrigerator - Google Patents

Abstract

The invention relates to the technical field of refrigeration equipment, in particular to a GM refrigerator. The GM refrigerator comprises a driving device, a primary cold head, a secondary cold head, a damping table primary cold head, a damping table secondary cold head, a first fixing column, a second fixing column and a thermal connection; the primary cold head of the damping table is arranged on the lower side of the primary cold head, the primary cold head of the damping table is connected with a flange plate on the driving device through a first fixing column, and the primary cold head is connected with the primary cold head of the damping table through thermal connection; damping station second grade cold head sets up the downside at the second grade cold head, and damping station second grade cold head passes through the second fixed column and is connected with damping station first grade cold head, the second grade cold head passes through hot connection and is connected with damping station second grade cold head. And fix the damping table cold head through the fixed column to and support the cold head of GM refrigerator through the damping table cold head, can effectual reduction GM refrigerant cold head's vibration. The vibration of the GM refrigerant cold head can be effectively reduced.

Description

GM refrigerator

Technical Field

The invention relates to the technical field of refrigeration equipment, in particular to a GM refrigerator.

Background

With the continuous development and innovation of scientific technology, the extreme environment detection technology plays an important role in the day-to-day scientific research work. The low-temperature environment is an important experimental means and has irreplaceable effects on actual basic scientific research and industrial application, and common methods for achieving the temperature below 2K include J-T throttling, he3 refrigerators and dilution refrigerators. Due to the shortage of helium resources on the earth, the GM refrigerator or the pulse tube refrigerator is used as a cold source to realize a fully closed-cycle working mode, so that the helium resources can be effectively saved. The GM refrigerator has the advantages of high refrigerating power and convenience in actual operation and maintenance, and the vibration reduction problem needs to be considered when a dilution refrigerator or a low-temperature system lower than 2K is built on the premise of utilizing the GM refrigerator due to the fact that the GM refrigerator inevitably introduces high vibration in the working process due to the limitation of the working principle of the GM refrigerator.

The cryogenic low-temperature environment is one of important means for a precise measurement physical instrument to inhibit multiple measurement noises, so that a refrigerating machine system based on a 4.2K low-temperature refrigerating machine is widely applied. However, if mechanical vibration caused by the refrigerator is neglected, the cold end of the refrigerator is directly and mechanically coupled to the measurement sensitive element, so that the precise measurement process is seriously disturbed, and the noise background of measurement is raised. Therefore, different refrigerator systems often adopt corresponding vibration isolation and damping measures for the vibration of the cryogenic refrigerator.

However, the refrigerator used in the general precision measuring instrument has high requirements on the vibration of the cold head, because the cold head is the vibration source closest to the sample cavity measured by the instrument, the peak value of the amplitude of the cold head of the refrigerator is less than or equal to +/-10 um at normal temperature, and even the sample cavity required to be correspondingly cooled at low temperature of 4.2k cannot exceed 30nm level due to the influence error of the vibration of the refrigerator, namely the vibration of the sample cavity caused by the cold head of the refrigerator serving as an internal vibration source cannot exceed 30nm.

Although the prior art has high requirements on cold head vibration, no effective measures for reducing cold head vibration exist in the prior art.

Disclosure of Invention

The invention aims to provide a GM refrigerant, which can solve the problem of large cold head vibration in the prior art;

the invention provides a GM refrigerator, which comprises a driving device, a primary cold head, a secondary cold head, a damping table primary cold head, a damping table secondary cold head, a first fixing column, a second fixing column and thermal connection, wherein the driving device is connected with the driving device;

the primary cold head of the damping table is arranged on the lower side of the primary cold head, the primary cold head of the damping table is connected with a flange plate on the driving device through a first fixing column, and the primary cold head is connected with the primary cold head of the damping table through thermal connection;

damping station second grade cold head sets up the downside at the second grade cold head, and damping station second grade cold head passes through the second fixed column and is connected with damping station first grade cold head, the second grade cold head passes through hot connection and is connected with damping station second grade cold head.

Preferably, the damping platform primary cold head is of an annular structure, and the damping platform primary cold head and the primary cold head are arranged coaxially.

Preferably, the damping platform secondary cold head is of an annular structure, and the damping platform secondary cold head and the secondary cold head are arranged coaxially.

Preferably, the first fixing column and the second fixing column are both made of glass fiber reinforced materials.

Preferably, the GM refrigerator includes a plurality of first and second fixed columns uniformly disposed.

Preferably, the number of the first fixed column and the second fixed column is in direct proportion to the damping effect and in inverse proportion to the refrigerating capacity.

Preferably, the thermal connection is elastic.

Preferably, the thermal connection between the primary cold head and the secondary cold head of the damping table is made of oxygen-free copper.

Preferably, the material adopted by the thermal connection between the second-stage cold head and the second-stage cold head of the damping table is pure Al.

Has the beneficial effects that:

constitute the shock attenuation platform through shock attenuation platform one-level cold head and shock attenuation platform second grade cold head to fix the shock attenuation platform cold head through the fixed column, and support the cold head of GM refrigerator through the shock attenuation platform cold head, can the effectual vibration that reduces GM refrigerant cold head.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.

FIG. 1 is a schematic diagram of the structure of GM refrigerant provided by an embodiment of the present invention;

FIG. 2 is a GM provided by an embodiment of the present invention;

description of reference numerals:

1: drive device, 2: primary cold head, 3: secondary cold head, 4: shock attenuation platform one-level cold head, 5: damping table second grade cold head, 6: first fixing column, 7: second fixing column, 8: and (4) thermally connecting.

Detailed Description

The technical solutions of the present invention will be described clearly and completely with reference to the following embodiments, and it should be understood that the described embodiments are some, but not all, embodiments of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

In the description of the present invention, it is to be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", and the like, indicate orientations and positional relationships based on those shown in the drawings, and are used only for convenience of description and simplicity of description, and do not indicate or imply that the device or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and thus, should not be considered as limiting the present invention.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, features defined as "first", "second", may explicitly or implicitly include one or more of the described features. In the description of the present invention, "a plurality" means two or more unless specifically defined otherwise. Furthermore, the terms "mounted," "connected," and "connected" are to be construed broadly and may, for example, be fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meanings of the above terms in the present invention can be understood in specific cases to those skilled in the art.

The embodiment provides a GM refrigerator, which comprises a driving device 1, a first-stage cold head 2, a second-stage cold head 3, a damping platform first-stage cold head 4, a damping platform second-stage cold head 5, a first fixing column 6, a second fixing column 7 and a thermal connection 8.

The primary cold head 4 of the damping table is arranged on the lower side of the primary cold head 2, the primary cold head 4 of the damping table is connected with a flange plate on the driving device 1 through a first fixing column 6, and the primary cold head 2 is connected with the primary cold head 4 of the damping table through a thermal connection 8;

damping platform second grade cold head 5 sets up the downside at second grade cold head 3, and damping platform second grade cold head 5 is connected with damping platform one-level cold head 4 through second fixed column 7, second grade cold head 3 is connected with damping platform second grade cold head 5 through hot junction 8.

In the embodiment, the damping table is formed by the damping table primary cold head 4 and the damping table secondary cold head 5, the damping table cold head is fixed through the fixing column, the cold head of the GM refrigerator is supported through the damping table cold head, and the vibration of the GM refrigerant cold head can be effectively reduced.

Specifically, damping station one-level cold head 4 is annular structure, and damping station one-level cold head 4 sets up with one-level cold head 2 coaxial line.

Damping platform second grade cold head 5 is annular structure, damping platform second grade cold head 5 sets up with second grade cold head 3 coaxial line.

The first fixing column 6 and the second fixing column 7 are both made of glass fiber reinforced materials. In order to effectively reduce vibration and not influence the refrigerating performance of the refrigerating machine, the G-FRP (glass fiber reinforced plastic) is selected as the material of the fixed columns, the material has good rigidity and very small heat conductivity coefficient, and the loss of refrigerating capacity is avoided while a rigid body which is not easy to vibrate is formed.

The GM refrigerator comprises a plurality of first fixing columns 6 and second fixing columns 7 which are uniformly arranged. The number of first and second fixed cylinders 6, 7 is directly proportional to the damping effect and inversely proportional to the refrigeration capacity. The number of the fixed columns can be selected according to the conditions such as the size of the cavity required by scientific research experiments.

The thermal connection 8 is elastic. The material requirement of thermal connection 8 is that when having very good coefficient of heat conductivity, possess a bit slight elasticity, play and support the damping effect, transfer the refrigerating output to the cold head of damping platform from the refrigerator cold head simultaneously, conveniently connect to the working part with the copper pigtail and accomplish refrigeration work.

The thermal connection 8 between the first-stage cold head 4 and the first-stage cold head 2 of the damping table is made of oxygen-free copper. The thermal connection 8 between the second-stage cold head 5 and the second-stage cold head 3 of the damping table is made of pure Al. Oxygen-free copper and pure Al are good thermal link materials, and because the oxygen-free copper has good heat transfer performance and small heat loss when the oxygen-free copper is higher than 50k, and the pure Al has good heat transfer performance and small heat loss when the oxygen-free copper is lower than 50k, the oxygen-free copper is adopted as a thermal link for a first-stage damping table cold head, and the pure Al is adopted as a thermal link for a second-stage damping table cold head, the device has more efficient refrigerating capacity under the condition of extremely low vibration compared with a PT refrigerating machine and a common GM refrigerating machine.

Finally, it should be noted that: the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit the same; while the invention has been described in detail and with reference to the foregoing embodiments, it will be understood by those skilled in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some or all of the technical features may be equivalently replaced; and these modifications or substitutions do not depart from the spirit of the corresponding technical solutions of the embodiments of the present invention.

Claims (9)

1. A GM refrigerator is characterized by comprising a driving device, a primary cold head, a secondary cold head, a damping table primary cold head, a damping table secondary cold head, a first fixing column, a second fixing column and thermal connection;

the primary cold head of the damping table is arranged on the lower side of the primary cold head, the primary cold head of the damping table is connected with a flange plate on the driving device through a first fixing column, and the primary cold head is connected with the primary cold head of the damping table through thermal connection;

damping station second grade cold head sets up the downside at the second grade cold head, and damping station second grade cold head passes through the second fixed column to be connected with damping station one-level cold head, the second grade cold head passes through hot junction and is connected with damping station second grade cold head.

2. The GM refrigerator of claim 1, wherein the shock mount primary cold head is of annular configuration, the shock mount primary cold head being coaxially disposed with the primary cold head.

3. The GM refrigerator of claim 1, wherein the shock mount secondary cold head is an annular structure, the shock mount secondary cold head and secondary cold head being coaxially disposed.

4. The GM refrigerator of claim 1, wherein the first and second fixed posts are both made of fiberglass reinforced material.

5. The GM refrigerator of claim 1 or 4, comprising a plurality of uniformly arranged first and second fixed posts.

6. The GM refrigerator of claim 1 or 4, wherein the number of first and second fixed columns is directly proportional to the damping effect and inversely proportional to the refrigeration capacity.

7. The GM refrigerator of claim 1, wherein the thermal connection is resilient.

8. The GM refrigerator of claim 1, wherein the thermal connection between the damper station primary cold head and the primary cold head is made of oxygen free copper.

9. The GM refrigerator of claim 1, wherein the thermal connection between the damper stage secondary cold head and the secondary cold head is made of pure Al.

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