JP2725689B2 - Regenerator refrigerator - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a regenerative refrigerator using a gido-female mahmahon cycle or the like.

[0002]

2. Description of the Related Art In a conventional regenerative refrigerator, as means for raising the temperature of a cooling unit in a low temperature state, 1) a method of breaking adiabatic vacuum, and 2) a heater provided in a cooling stage. There are methods such as passing an electric current and raising the temperature by the generated Joule heat.However, these methods require a long heating time, require power supply equipment, or have a problem of heater deterioration. There are drawbacks.

[0003]

SUMMARY OF THE INVENTION In a regenerative refrigerator using a Gifford-McMahon cycle or the like, in a process of raising the temperature of a cooling unit in a low temperature state, it is necessary to shorten the temperature raising time and to reduce the cooling step. -To regulate the temperature of the die.

[0004]

A high-pressure helium gas compressed by the helium compressor 1 and a low-pressure helium gas adiabatically expanded by the open / close switching of the intake valve 2 and the exhaust valve 3. When the helium gas flows alternately in the first stage regenerator 10 and the second stage regenerator 14 in opposite directions, the high-temperature and high-pressure helium gas and the low-temperature and low-pressure helium gas repeat heat exchange through the regenerator material, Cold storage in which the temperature of the gas in the first-stage expansion chamber 20 and the second-stage expansion chamber 21 is lowered, and the first-stage cooling stage 11 and the second-stage cooling stage 15 are cooled via the cylinders 8 and 12. In a regenerative refrigerator, a conduit provided with a temperature control valve is branched from the high / low pressure gas flow path 4 of the refrigerator, and the conduit is connected to a heat generating portion which is in thermal contact with a cooling stage. Same as refrigerant gas supplied to 10, 14 The gas having the cycle and the pressure is supplied to the heat generating portion, and the gas is heated by adiabatic compression heat generated when the gas is supplied to the heat generating portion.

[0005]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Gifford McMahon cycle type refrigerator
The refrigeration operation of a GM cycle refrigerator will be described with reference to FIG. By switching between opening and closing of the intake valve 2 and the exhaust valve 3, the high-pressure helium gas compressed by the helium compressor 1 and the low-pressure helium gas whose adiabatic expansion and lowering temperature are reduced by the first stage regenerator. When the gas flows alternately in the direction 10 and the second stage regenerator 14 in the opposite direction, helium gas of high temperature and high pressure and helium gas of low temperature and low pressure exchange heat via the regenerator material. The temperature of the gas in the first-stage expansion chamber 20 and the second-stage expansion chamber 21 is reduced by this repetition means, and the cold thereof is reduced through the cylinder to the first-stage cooling stage.
The cooling is transmitted to the die 11 and the second stage cooling stage 15.

The conventional method of raising the temperature or adjusting the temperature of each cooling stage cooled by such means is the heater provided in the first and second stage cooling stages 11 and 15. It is a general method to apply a current to the heaters 16 and 18 to raise the temperature by Joule heat generated, and to perform the control by a control circuit combined with a temperature sensor.

The configuration of the temperature raising means of the refrigerator according to the present invention will be described with reference to FIG. High and low pressure gas passages are provided in the first and second stage heat generating parts 22 and 23 (spaces of a certain volume) provided in the first and second stage cooling stages 11 and 15 instead of the conventional heater. The first stage and the second stage heat generating parts 22, 23, which are in thermal contact with the cooling stage via the temperature control valves 6, 7, and the working gas of the refrigerator branched from the line 4, form conduits 22a, 23a. And are connected by. This heating part 22, 2
3 is filled with gas having the same cycle of pressure as that supplied to the first and second regenerators 10 and 14 (adiabatic compression). No special equipment such as a power supply is required as a means for generating heat. In the case of FIG. 2, the same as the temperature control valve (A) 6,
(B) An electromagnetic valve is used for 7, and the opening and closing of the electromagnetic valve is controlled by an instruction from the temperature control circuit. In the case of the cooling operation of the refrigerator or when the temperature of the cooling stage is not raised, the temperature control valves 6 and 7 are in a closed state.

[0008]

Operation The operation of the temperature raising process according to the present invention will be described with reference to FIG. In addition, each cooling stage 11 of the refrigerator,
The temperature of No. 15 has reached the low temperature steady state, and the second cooling stage
A case where only the temperature of the die 15 is raised from the ultimate temperature of 10K to 50K will be described.

[0009] Open the temperature control valve (B) 7 (temperature control valve (A) 6
Is closed), the gas having the same cycle as that supplied to the regenerators 10 and 14 is supplied to the space of the second-stage heat generating part 23 through the conduit 23a.
Is supplied via At this time, heat is generated in the second-stage heating section 23 by adiabatic compression heat generated by the gas being packed in the space. By this repetition means, the second heat generating portion 23
Is heated, and the second stage cooling stage 15 is heated to 50K. When the temperature of the second stage cooling stage 15 is raised to 50K, the control circuit detects the temperature from the second stage temperature sensor 19, and the temperature control valve B7 is closed.

Next, a two-stage GM cycle refrigerator (refrigeration capacity: 77K / 20W for one stage, 20K / 4W / 50H for two stages)
An embodiment using Z) (only the second stage cooling stage is heated) will be described with reference to FIG. In this case, the second-stage heating section 23 is made of a material C1100, weighs 0.5 kg, and has a space volume of 8.
In the configuration of 0 cm ³ , the minimum temperature is 10K to 50K.
The temperature rise time to K was within 2 minutes. It was also possible to adjust the flow path of the temperature control valve B7 (manual valve in the embodiment) to maintain the two-stage cooling stage 15 at 70K. The cooling stage 1 when the flow path of the control valve B7 is fully opened.
The temperature of Sample No. 5 was about 115K, and the heat input to the refrigerator used was a calorific value corresponding to about 23W. FIG. 4 shows the result of temperature measurement in this embodiment.

[0011]

[Effect] As a means for raising the temperature, a heat generation effect by adiabatic compression of gas when high-pressure helium gas is supplied into a space provided in a cooling stage or an object to be cooled is used.
In particular, it has become possible to raise and control the temperature without the need for power supply equipment. Further, since the temperature can be raised without stopping the refrigerator, for example, when used as a cryopump refrigerator, the time required for the cryopanel regeneration operation (loss time as a cryopump) is greatly reduced. You. In addition, the refrigerator drive unit 5 of the present apparatus is used as a temperature raising means.
By rotating in the direction opposite to the rotation of the cooling mode, a higher temperature raising effect can be obtained.

[Brief description of the drawings]

FIG. 1 shows a known GM cycle refrigerator.

FIG. 2 shows a GM cycle refrigerator provided with a temperature raising means according to the present invention.

FIG. 3 also shows a two-stage GM cycle refrigerator.

FIG. 4 is a view showing a result of temperature measurement in the example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Helium compressor 2 Intake valve 3 Exhaust valve 4 High-low pressure gas flow path 5 Drive part 6,7 Temperature control valve 8 First-stage cylinder 9 First-stage displacer 10 First-stage regenerator 11 First-stage cooling stage 12 Second-stage cylinder 13 Second-stage displacer 14 Second-stage regenerator 15 Second-stage cooling stage 16 Heater 17 First-stage temperature sensor 18 Heater 19 Second-stage temperature sensor 20 First Step expansion chamber 21 Second stage expansion chamber 22 First stage heating section 23 Second stage heating section 22a Conduit 23a Conduit

Claims (1)

(57) [Claims] 1. The high-pressure helium gas compressed by the helium compressor (1) and the high-pressure helium gas are adiabatically expanded by the switching of the opening and closing of the intake valve (2) and the exhaust valve (3), and the temperature is lowered. Low-pressure helium gas is the first-stage regenerator (10)
And the second-stage regenerator (14) alternately flow in the opposite direction, the high-temperature and high-pressure helium gas and the low-temperature and low-pressure helium gas repeat heat exchange via the regenerator material, and the first-stage expansion chamber (20) And the second
The temperature of the gas in the stage expansion chamber (21) is lowered, and the first stage cooling stage (11) and the second stage cooling stage are moved through the cylinders (8, 12).
In a regenerative refrigerator that cools the di (15),
A conduit provided with a temperature control valve is branched from the high and low pressure gas flow path (4) of the refrigerator, and the branch is connected to a heat generating portion which is in thermal contact with a cooling stage, and a regenerator (10, 14) is provided. A) a gas having the same cycle and pressure as the refrigerant gas to be supplied to the heat generating section, and heated by adiabatic compression heat generated when the gas is supplied to the heat generating section. .