JPH11173683A - Cryogenic apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an apparatus which enables the generation of a cryogenic temperature area while allowing a lower cost and a smaller size without depending on a refrigerant used. SOLUTION: In a first circuit, a gaseous phase refrigerant discharged from the discharge side 1a of a compressor 1 enters a condenser 3 via a pre-condenser 2. Then, the refrigerant flows out of a first passage 3b of the condenser 3, runs in the order of a first passage 4a of a first heat exchanger 4, a first passage 5a of a precooler 5, a first passage 6a of a second heat exchanger 6, a first passage 7a of a heat storage 7 and an expansion means 17 and enters a cooler 8. In a second refrigerant circulation circuit, the gaseous phase refrigerant after cooled flows out of the cooler 8, runs in the order of a second passage 7b of the heat storage 7, a second passage 6b of the heat exchanger and a second passage 4b of the first heat exchanger and reaches the suction side 1b of the compressor 1. In a second refrigerant circulation circuit, the gaseous phase refrigerant from the discharge side 1a of a compressor enters the condenser 3 via the pre-condenser 2 and returns to the suction side 1b of the compressor 1 passing through an expansion valve 9 and a second passage 5b of the pre-cooler from a second passage 3c and further through the second passage 4b of the first heat exchanger 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an apparatus for producing a cryogenic temperature used in many fields such as the vacuum industry, physics and chemistry, chemistry, and food.

[0002]

2. Description of the Related Art Various types of refrigeration systems have been proposed for reducing a substance below its natural temperature by using artificial means. The refrigerating apparatus includes a compressor, a condenser, an expansion valve, and an evaporator. The refrigerant is sucked by the compressor, compressed to a high-temperature, high-pressure gas phase, and the high-temperature, high-pressure gas phase refrigerant is condensed by the condenser. After cooling to a liquid state using surrounding air or cooling water, the liquid-phase refrigerant is depressurized by an expansion valve,
It is sent to the evaporator and the evaporator absorbs heat from the low-temperature object to be cooled, such as ambient air or antifreeze, and at this time, obtains a refrigeration effect on the object to be cooled, and returns the refrigerant after absorbing the heat to the compressor again. There is a single-stage compression refrigeration system. However, in the single-stage compression refrigeration apparatus described above, refrigeration can be performed up to a temperature higher than -30 ° C. Since the compression ratio increases, the volumetric efficiency and the compression efficiency of the refrigerant decrease, and the temperature of the refrigerant at the compressor outlet rises, causing problems such as deterioration of lubricating oil and the like. To generate a low temperature range of about ゜ C, a two-stage refrigeration system in which a compressor is divided into a low pressure side and a high pressure side has been used. In the case of generating a lower temperature, specifically, a low-temperature region of -70 ° C or less, a so-called cryogenic region, a refrigerant having a low boiling point that is different in stages is used in order to avoid a low evaporation pressure due to a cryogenic temperature. A multi-component refrigeration system is used in which two or more types are used to evaporate a refrigerant having a higher boiling point in a condenser and condense the refrigerant having a lower boiling point by the latent heat.

[0003]

However, since a multi-component refrigeration system which can achieve extremely low temperatures uses two or more different refrigerants as described above, an independent refrigeration circuit is required for each refrigerant. However, there is a problem that the number of parts is large, the structure is complicated and the production cost is high, and there is also a problem that the whole size is large and the installation place is large.
Further, in the above-described multi-component refrigeration apparatus, it is necessary to increase the type of refrigerant to be used as the generated temperature is lowered,
Since the number of refrigeration circuits must be increased accordingly, there is also a problem that the lower the temperature to be generated, the greater the above-mentioned problems. Further, needless to say, these multi-unit refrigeration apparatuses have a problem that the operation cost is enormous because two or more refrigeration circuits must be operated. In recent years, the use of inexpensive chlorofluorocarbon gas with a high heat exchange rate tends to be restricted due to the destruction of the ozone layer. As a result, a refrigeration system uses a substitute refrigerant having a lower heat exchange rate than chlorofluorocarbon gas. However, there is a strong demand for obtaining a high refrigeration effect while maintaining the conventional power. An object of the present invention is to solve the above-described problems and to provide a cryogenic device capable of achieving generation of a cryogenic region at low cost and small size without depending on a refrigerant to be used.

[0004]

In order to achieve the above-mentioned object, a cryogenic apparatus according to the present invention is arranged such that a liquid-phase refrigerant discharged from a discharge side of a compressor flows into a condenser through a pre-condenser. And flows out of the first flow path of the condenser, the first flow path of the first heat exchanger, the first flow path of the precooler, the first flow path of the second heat exchanger, and the heat storage device. Passes through the first flow path and the expansion means in order, and enters the cooler, and the cooled gas-phase refrigerant flows out of the cooler and flows into the second flow path of the heat storage device and the second flow path of the second heat exchanger. The first refrigerant circulation circuit which passes through the flow path of the first heat exchanger and the second flow path of the first heat exchanger and returns to the suction side of the compressor, and the liquid phase refrigerant discharged from the discharge side of the compressor is The fluid flows into the condenser via the condenser, flows out of the second flow path of the condenser, passes through the second flow path of the expansion valve and the pre-cooler, and further passes through the first flow path of the first heat exchanger. Pass through It and a second refrigerant circuit back to the suction side of the compressor is characterized in.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an embodiment of a cryogenic apparatus according to the present invention will be described with reference to the accompanying drawings showing an embodiment of the present invention. FIG. 1 is a schematic piping diagram of a cryogenic device according to the present invention. As shown in the drawing, this cryogenic device includes a compressor 1, a pre-condenser 2, a condenser 3, a first heat exchanger 4, a pre-cooler 5, a second heat exchanger 6, a regenerator 7, and a cooler. 8 and a refrigerant circulation circuit including an expansion valve 9, and drives the compressor 1 to circulate refrigerant in the refrigerant circuit;
The cooler 8 is configured to obtain an extremely low temperature of −120 ° C. or less.

An oil separator 10, a CHV 11, and a pre-condenser 2 are interposed between a discharge port 1a of the compressor 1 and an inlet 3a of the condenser 3. The condenser 3 has two outlets 3b
, 3c, and the first outlet 3b is connected to the first heat exchanger 4 via two dryer replacement valves 12, 13 and a dryer 14. The first heat exchanger 4 includes a first flow path 4a and a second flow path 4b, and a first outlet 3b of the condenser 3 is connected to the first flow path 4a.
a is connected to the precooler 5. The pre-cooler 5
The first heat exchanger 4 includes a first flow path 5a and a second flow path 5b. The first flow path 4a of the first heat exchanger 4 is connected to the first flow path 5a. It is connected to the. The second heat exchanger 6 includes a first flow path 6a and a second flow path 6b, and the first flow path 5a of the pre-cooler 5 is connected to the first flow path 6a. It is connected to the regenerator 7. The heat storage unit 7 includes a first flow path 7a and a second flow path 7b, and the first flow path 6a of the second heat exchanger 6 is connected to the first flow path 7a. Cooler 8 via capillary 17
Is connected to the inlet 8a. Outlet 8b of cooler 8
Is returned to the regenerator 7 again and connected to the second flow path 7b. The second flow path 7b of the regenerator 7 is connected to the first heat exchanger 6 via the second flow path 6b of the second heat exchanger 6. The outlet of the second flow path 4b of the first heat exchanger 4 is connected to the suction port 1b of the compressor 1. With the configuration described above, the compressor 1 (discharge port 1a) -oil separator 10-CHV
11-Precondenser 2-Condenser 3 (first outlet 3b) -Valve 12-Dryer 14-Valve 13-First heat exchanger 4
(First flow path 4a)-pre-cooler 5 (first flow path 5a)-second heat exchanger 6 (first flow path 6a)-regenerator 7 (first flow path 7)
a) -Capillary tube 17-Cooler 8-Regenerator 7 (second flow path 7)
b) -the second heat exchanger 6 (the second flow path 6b) -the first heat exchanger 4 (the second flow path 4b) -the compressor 1 (the suction port 1b). A first refrigerant circuit is configured.

The second outlet 3c of the condenser 3 is
The precooler 5 is connected to the second flow path 5b via a valve 15, a dryer 16 and an expansion valve 9. The second flow path 5b of the precooler 5 is connected to the second flow path 4b of the first heat exchanger 4.
To the compressor 1 (discharge port 1a) -oil separator 10-CH
V11-Precondenser 2-Condenser 3 (second outlet 3c)-
Valve 15-dryer 16-expansion valve 9-precooler 5
(2nd flow path 5a)-1st heat exchanger 4 (2nd flow path 4b)-
A second refrigerant circuit through which the refrigerant flows in the order of the compressor 1 (the suction port 1b) is configured.

Here, the simple operation of the cryogenic device configured as described above will be described.
After the oil component thereof is separated by the oil separator 10, the liquid-phase refrigerant discharged from the tank flows into the condenser 3 via the pre-condenser 2. The liquid-phase refrigerant flowing out of the second outlet 3c of the condenser 3 is expanded by the expansion valve 9, and then returns to the compressor 1 via the pre-cooler 5 and the first heat exchanger 4. That is, it passes through the second refrigerant circuit. On the other hand, when the liquid-phase refrigerant flowing out of the first outlet 3b of the condenser 3 passes through the first heat exchanger 4, the low-temperature low-pressure refrigerant passing through the second refrigerant circuit and the cooler in the first refrigerant circuit After passing through the pre-cooler 5, it is cooled by heat exchange with the refrigerant after passing, and is further supercooled by a low-temperature low-pressure refrigerant immediately downstream of the expansion valve 9 in the second refrigerant circuit. After the refrigerant cooled by the first heat exchanger 4 and the pre-cooler 5 is further cooled by exchanging heat with the refrigerant after passing through the cooler in the second heat exchanger 6 and the heat storage 7,
It is expanded when flowing out of the capillary tube 17, is brought into a low pressure state at an extremely low temperature of −120 ° C. or less, and flows into the cooler 8. The cryogenic low-pressure liquid-phase refrigerant is vaporized in the cooler to cool the ambient temperature to −120 ° C. or lower to become a cryogenic low-pressure liquid-phase refrigerant. Flows through the heat exchanger 6 and the first heat exchanger 4 and passes therethrough.
The gas-phase refrigerant before passing through the cooler 8 in the refrigerant circuit is cooled. By the above operation, the liquid-phase refrigerant flowing in the first refrigerant circuit is efficiently cooled by the refrigerant flowing in the second refrigerant circuit and the cryogenic liquid-phase refrigerant after passing through the cooler 8 in the first refrigerant circuit. , A very low temperature atmosphere of −120 ° C. or less can be generated in the cooler 8. FIG. 2 shows that the cryogenic apparatus shown in FIG.
It is a graph which shows driving | operation using three types of frequencies of 0 Hz and 60 Hz, and which measured the temperature obtained by the cooler 8, and which shows the experimental result. The vertical axis indicates the temperature, and the horizontal axis indicates the time. From this experimental result, -120 is obtained at any frequency.
It can be seen that an extremely low temperature of ゜ C or less has been obtained.

The cryogenic device configured as described above is configured to be driven at a low pressure and in a vacuum state. When the refrigerant is cooled to a cryogenic temperature, moisture and oil solidify. It is configured not to block the refrigerant circuit. Therefore, when replacing the dryers 14 and 16,
In order to maintain a vacuum state in the refrigerant circuit, each valve 1
After closing the valves 2, 13 and 15, the work is performed, and after the dryers 14 and 15 are replaced, the dryer mounting portion is returned to a vacuum state via the valve 18 and then the valves 12, 1 and 15 are replaced.
Open valves 3 and 16.

The cryogenic device configured as described above has a defrost circuit for defrosting the cooler 8. The defrost circuit includes a first flow path 20 that bypasses a flow path downstream of the condenser 3 in the first refrigerant circuit and an inflow port 8a of the cooler 8, and a flow path downstream of the cooler 8 in the first refrigerant circuit. A second flow path 21 that bypasses the flow path and the first heat exchanger 4 is provided. Each flow path 20 and 21 has a solenoid valve 20a
And 21a are provided, and during the defrosting operation, the two solenoid valves 20a and 21a are opened to guide the refrigerant to the defrosting circuit. Further, the first flow path 20 is disposed so as to pass near a flow path connecting the discharge port 1a of the compressor 1 and the oil separator 10, whereby the first flow path is provided during the defrosting operation. The refrigerant passing through the passage 20 is configured to be heated by a high-temperature refrigerant immediately discharged from the compressor 1. With the above-described configuration, during the defrosting operation, the refrigerant flowing out of the first outlet 3b of the condenser 3 passes through the valve 12, the dryer 14, and the valve 13 from the position indicated by reference numeral D1 in FIG. 20, is heated by the refrigerant discharged from the compressor 1 when passing through the position indicated by reference numeral D2, and further passes through the positions indicated by reference numerals D3 and D4 in order, and cools from the position indicated by reference numeral D5 via the solenoid valve 20. The defrosted refrigerant enters the vessel 8 and the defrosted refrigerant flows from the position indicated by the reference sign D7 into the second flow path 21 through the position indicated by the reference sign D6, and passes through the position indicated by the reference sign D8 to the first heat Exchanger 4
And flows back to the compressor 1 from there.

In the cryogenic device configured as described above, a capillary tube 17 is provided between the regenerator 7 and the inlet 8a of the cooler 8 to expand the refrigerant in the first refrigerant circuit. However, this is not limited to the present embodiment, and may be expanded by, for example, providing an expansion valve.

[0012]

As described above, in the cryogenic device according to the present invention, the liquid refrigerant discharged from the discharge side of the compressor is:
After flowing into the condenser through the pre-condenser, flowing out of the first flow path of the condenser and flowing out of the first flow path of the first heat exchanger, the first flow path of the pre-cooler, the second heat exchanger Of the first flow path, the first of the regenerator
Pass through the flow path and the expansion means in order, enter the cooler, the cooled gas-phase refrigerant flows out of the cooler, the second flow path of the regenerator, the second flow path of the second heat exchanger A first refrigerant circulation circuit that passes through the second flow path of the first heat exchanger in order and returns to the suction side of the compressor, and a liquid-phase refrigerant discharged from the discharge side of the compressor,
It enters the condenser via the pre-condenser, flows out of the second flow path of the condenser, passes through the expansion valve and the second flow path of the pre-cooler, and further passes through the first flow of the first heat exchanger. A second refrigerant circulation circuit that passes through the path and returns to the suction side of the compressor, so that the refrigerant before passing through the cooler in the first refrigerant circuit, the refrigerant that passes through the second refrigerant circuit, Efficiently cools with the refrigerant after passing through the cooler in the first refrigerant circuit to -120
It cools down to cryogenic temperature of ゜ C or less, a cryogenic atmosphere of -120 ° C or less can be obtained with a cooler, and one refrigeration circuit is not required, unlike a conventional multi-component refrigeration system, which does not require a plurality of independent refrigeration circuits. This has the effect of obtaining a very low-temperature atmosphere, and as a result, has the effect of reducing the size of the device and reducing the manufacturing cost.Furthermore, since a plurality of types of refrigerants are not required, the cost of the refrigerant is also reduced. This has the effect of saving money. Also, since only one compressor is required, the power required for operation is extremely small as compared with the conventional multi-component refrigeration system,
An effect is obtained that an efficient freezing effect is obtained. In addition, with the above-described configuration, high refrigeration efficiency is obtained, so that a sufficient refrigeration effect can be obtained with other refrigerants without using a conventionally used high-fluorocarbon gas having a high heat exchange rate. It is also environmentally friendly. Therefore, the cryogenic device according to the present invention is very high in that the cryogenic device can be easily used in various fields because the device is downsized, the manufacturing cost is low, and the cost for operation is low. It works.

[Brief description of the drawings]

FIG. 1 is a schematic piping diagram of a cryogenic device according to the present invention.

FIG. 2 shows the cryogenic apparatus shown in FIG.
It is a graph which shows the experiment result which operated using the 00V alternating current power supply at three types of frequency of 40 Hz, 50 Hz, and 60 Hz, and measured the temperature obtained by the cooler 8.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor 1a Discharge port 1b Suction port 2 Precondenser 3 Condenser 3a Inflow port 3b 1st outflow port 3c 2nd outflow port 4 1st heat exchanger 4a 1st flow path 4b 2nd flow path 5 Precooler 5a 1st flow path 5b 2nd flow path 6 2nd heat exchanger 6a 1st flow path 6b 2nd flow path 7 regenerator 7a 1st flow path 7b 2nd flow path 8 cooler 8a inflow 8b outflow 9 expansion valve Reference Signs List 10 oil separator 11 CHV 12 valve 13 valve 14 dryer 15 valve 16 dryer 17 capillary tube 18 valve 20 first flow path 20a solenoid valve 21 second flow path 21a solenoid valve

Claims (1)

[Claims] A liquid-phase refrigerant discharged from a discharge side (1a) of a compressor (1) flows into a condenser (3) through a pre-condenser (2), and is supplied to a first condenser (3) of the condenser (3). Out of the flow path (3b) of the first heat exchanger (4)
A first flow path (4a), a first flow path (5a) of the pre-cooler (5),
It passes through the first flow path (6a) of the second heat exchanger (6), the first flow path (7a) of the regenerator (7) and the expansion means (17) in this order, and enters the cooler (8). The cooled gas-phase refrigerant flows out of the cooler (9), and flows through the second flow path (7b) of the regenerator (7) and the second flow path (6b) of the second heat exchanger (6). A first refrigerant circulation circuit passing through the second flow path (4b) of the first heat exchanger (4) and returning to the suction side (1b) of the compressor (1); The liquid-phase refrigerant discharged from the discharge side (1a) flows into the condenser (3) through the pre-condenser (2), flows out from the second flow path (3b) of the condenser (3), and expands. Valve (9) and pre-cooler (5)
Through the second flow path (5b) and further through the first flow path (4b) of the first heat exchanger (4) and returning to the suction side (1b) of the compressor (1). A cryogenic device, comprising: