JP2000028284A - Compression type refrigerating machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the risk of leakage of a refrigerant in a compression type refrigerating machine for circulating the refrigerant by connecting an evaporator, a compressor, a condenser and a throttle valve together through a piping. SOLUTION: In a compression type refrigerating machine, the entire length or a part of a piping in which a refrigerant flows is formed in a double pipe structure comprising an inner pipe 54 and an outer pipe 55. A part between the inner pipe 54 and the outer pipe 55 is filled with a quick binder 6 quickly solidified upon coming into contact with outside air, electroviscous fluid solidified by applying voltage thereto, a refrigerant absorbent, an oxidizer for oxidizing the refrigerant or compressed carbon dioxide gas.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a compression refrigerator using natural refrigerants such as hydrocarbons and ammonia as refrigerants.

[0002]

2. Description of the Related Art In general, a compression refrigerator has an evaporator (1), a compressor (2), a condenser (3) and a throttle valve as shown in FIG.
(4) is connected to each other by pipes (5), (51), (52) and (53) to realize a refrigeration cycle as shown in FIG. That is, the refrigerant gas from the evaporator (1) is supplied to the compressor (2).
The refrigerant gas is compressed (→) to become a high-temperature, high-pressure gas, and the refrigerant gas discharged from the compressor (2) is sent to the condenser (3) and is condensed by releasing heat to a high-temperature heat source (outside air). →). The high-temperature, high-pressure refrigerant liquid liquefied by condensation is supplied to the throttle valve (4), and becomes a low-temperature, low-pressure refrigerant liquid by expansion (→). The refrigerant liquid from the throttle valve (4) is sent to the evaporator (1), removes heat from the low-temperature heat source (freezer), evaporates (→), and is supplied to the compressor (2) as refrigerant gas. . By repeating the above refrigeration cycle (→→→→), heat is transferred from the low-temperature heat source to the high-temperature heat source, and the low-temperature heat source is cooled. As the refrigerant, CFC, HCFC, HFC, and other such refrigerants based on Freon (trade name of DuPont) are most widely used.

[0003] In recent years, chlorofluorocarbon, which has been widely used as a refrigerant, has become a major problem as a cause of depletion of the ozone layer and global warming, and there has been an increasing movement to completely eliminate chlorofluorocarbon as a refrigerant. Under such circumstances, natural refrigerants such as hydrocarbons and ammonia have received attention.

[0004]

However, even natural refrigerants are not without problems at all. For example, hydrocarbon refrigerants such as propane are flammable and explosive. Ammonia is not only toxic, has a strong odor, but also has low flammability. Accordingly, in a compression refrigerator employing such a natural refrigerant, for example, if the piping system is damaged by the action of vibration or impact force and the refrigerant leaks, there is a risk that a serious accident may occur, and for safety assurance. Measures are required.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a structure for preventing the leakage of refrigerant in order to reduce the risk of refrigerant leakage,
Another object of the present invention is to provide a compression refrigerator having a structure for detoxifying the leaking refrigerant even if the refrigerant leaks.

[0006]

In the first compression type refrigerator according to the present invention, the entire length or a part of the pipe through which the refrigerant flows is formed by a double pipe comprising an inner pipe (54) and an outer pipe (55). Structure.
Then, a space between the inner pipe (54) and the outer pipe (55) is filled with a quick fixing agent (6) which solidifies rapidly when it comes into contact with the outside air.

Therefore, even if the inner pipe (54) and the outer pipe (55) are broken and cracks occur in the pipe wall, the quick fixing agent (6)
Penetrates into the cracks of the outer tube (55), and when it comes out of the cracks, it comes into contact with the outside air and solidifies rapidly. This closes the crack and prevents leakage of the refrigerant. Here, if the quick fixing agent (6) is filled at a pressure higher than the outside air pressure, the rapid fixing agent (6) flows into the crack by the pressure, and the crack can be quickly closed.

In the second compression type refrigerator according to the present invention, the space between the inner tube (54) and the outer tube (55) is filled with an electrorheological fluid (61) which is solidified by applying a voltage, and On the wall,
A pair of electrodes (73) and (73) are arranged on both sides of the electrorheological fluid (61), and when damage to the piping is detected, the pair of electrodes
(73) A predetermined voltage is applied to (73).

Therefore, even if the inner pipe (54) and the outer pipe (55) are broken and a crack is generated on the pipe wall, the damage to the pipe is detected, so that a predetermined amount of the electrorheological fluid (61) is applied. When a voltage is applied, the electrorheological fluid (61) solidifies instantaneously. This closes the crack and prevents leakage of the refrigerant. In addition, regarding the damage of the pipe, a pressure sensor (7) for detecting the pressure of the refrigerant (81) or the electrorheological fluid (61) is provided, and the pressure fluctuation detected by the pressure sensor (7) sets a threshold value. When it exceeds, it can be determined that damage has occurred. Then, a predetermined voltage can be applied to the pair of electrodes (73) (73) by operating the drive circuit based on the determination result.

[0010] In the third compression refrigerator according to the present invention, a space between the inner pipe (54) and the outer pipe (55) is filled with a refrigerant absorbent (62).

Therefore, even if the inner pipe (54) and the outer pipe (55) are damaged and cracks occur in the pipe wall, first, the inner pipe (54)
When the refrigerant enters between the inner pipe (54) and the outer pipe (55) from the crack, the refrigerant is absorbed by the refrigerant absorbent (62). Is prevented from leaking. When ammonia is used as the refrigerant, the refrigerant absorbent (62) can be composed of a water-absorbing polymer containing water.

In the fourth compression refrigerator according to the present invention, an oxidizing agent (63) that causes an oxidation reaction with the refrigerant is filled between the inner pipe (54) and the outer pipe (55).

Therefore, even if the inner pipe (54) and the outer pipe (55) are damaged and cracks occur in the pipe wall, first, the inner pipe (54)
From the cracks, the refrigerant enters between the inner pipe (54) and the outer pipe (55), whereby the refrigerant is oxidized by the oxidizing agent (63), and the substance generated by the oxidation becomes the outer pipe (55). Will leak out of the cracks. For example, if ammonia is used as a refrigerant, nitrogen and water are generated by oxidation, and if hydrocarbons are used as a refrigerant, only carbon dioxide and hydrogen are generated by oxidation, and toxicity and No explosive harmful substances leak out. In addition, as the oxidizing agent (63), for example, an oxide of a platinum group metal or a base metal can be used.

[0014] In the fifth compression refrigerator according to the present invention, a carbon dioxide gas source is disposed between the inner pipe (54) and the outer pipe (55). Therefore, even if the inner pipe (54) and the outer pipe (55) are damaged and a crack occurs in the pipe wall, when the refrigerant leaks out through the cracks in the inner pipe (54) and the outer pipe (55), , Inner pipe (5
Carbon dioxide gas is generated from the carbon dioxide gas source located between 4) and the outer pipe (55), and the refrigerant is diluted by the carbon dioxide gas and leaks outside in a safe state without toxicity or explosion Will be. In addition, as a carbon dioxide gas generation source, a compressed carbon dioxide gas, a carbon dioxide adsorbent adsorbing carbon dioxide molecules,
Alternatively, a carbon dioxide absorbent that has absorbed carbon dioxide molecules can be used.

[0015]

According to the compression refrigerator of the present invention, a structure for preventing the leakage of the refrigerant or a structure for rendering the refrigerant leaking harmless even if the leakage of the refrigerant occurs. Therefore, it is safe even if the pipe is broken and a crack occurs.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, an embodiment of the present invention applied to a compression refrigerator shown in FIG. 11 will be specifically described with reference to the drawings.

First Embodiment As shown in FIG. 1, evaporator outlet piping (5), compressor outlet piping
(51), the entire length of the condenser outlet pipe (52), and the throttle valve outlet pipe (53), or at least a section arranged in the room,
It has a double pipe structure composed of an inner pipe (54) and an outer pipe (55), and a refrigerant (8) flows inside the inner pipe (54). In addition, refrigerant
As (8), natural refrigerants such as hydrocarbons and ammonia are used. In addition, between the inner pipe (54) and the outer pipe (55), a quick fixing agent (6) which solidifies rapidly upon contact with the outside air.
Is filled at a pressure higher than the outside air pressure. As the fast fixing agent (6), for example, an instant adhesive such as an α-cyanoacrylate adhesive can be used.

Therefore, as shown in FIG. 2, even if the inner pipe (54) and the outer pipe (55) are broken and cracks (56) and (57) are generated on the pipe wall, as shown by arrows in FIG. Fast fixative (6) is outer tube
The crack (57) of (55) penetrates, and when it comes out of the crack, comes into contact with the outside air and is rapidly solidified to form a fixed layer (60). The cracks (57) are closed by the fixing layer (60), and leakage of the refrigerant is prevented.

As shown by a chain line in FIG. 2, if an outer skin layer (58) made of a heat insulating material or the like is provided over the outer peripheral surface of the outer tube (55), the quick fixation leaked from the crack (57) is achieved. The effect of holding the agent (6) in the vicinity of the crack (57) is obtained.

Second Embodiment As shown in FIG. 3, between an inner pipe (54) and an outer pipe (55), an electrorheological fluid (61) solidified by application of a voltage is filled at a pressure higher than the external pressure. At the same time, a plurality of linear electrodes (73) (73) extending along the tube axis are arranged at a plurality of places on the tube wall with the electrorheological fluid (61) interposed therebetween. These pair of electrodes
(73) and (73) are connected to the power supply circuit (72). As is well known, the electrorheological fluid (61) is a liquid in which fine particles are dispersed in an electrically insulating oil such as silicone oil, and is usually a low-viscosity liquid, but when a voltage is applied, the particles are connected to each other. This increases the viscosity and makes it rubbery.

A pressure sensor (7) for detecting the pressure of the electrorheological fluid (61) is provided between the inner pipe (54) and the outer pipe (55). The output signal is controlled by the control circuit (7
Supplied to 1). The control circuit (71) issues a voltage application command to the power supply circuit (72) when the fluctuation of the pressure detected by the pressure sensor (7) exceeds a predetermined threshold.
In response, the power supply circuit (72) applies a predetermined voltage to the pair of electrodes (73) (73).

Therefore, as shown in FIG. 4, even if the inner pipe (54) and the outer pipe (55) are broken and cracks (56) and (57) are generated on the pipe wall, the electrorheological fluid ( The pressure of 61) drops rapidly, and this pressure fluctuation is detected by the pressure sensor (7). Then, a predetermined voltage is applied to the pair of electrodes (73) (73) by the operation of the control circuit (71) and the power supply circuit (72), and as a result, the electrorheological fluid (61) solidifies instantaneously, A shaped layer (65) will be formed. The cracks (56) and (57) are closed by the rubber-like layer (65), and leakage of the refrigerant (81) is prevented. Incidentally, the pressure sensor (7) can be installed in the refrigerant (81), and the breakage of the pipe can be detected by the pressure fluctuation of the refrigerant (81).

Third Embodiment As shown in FIG. 5, a space between the inner pipe (54) and the outer pipe (55) is filled with a refrigerant absorbent (62). When ammonia is used as the refrigerant (82), the refrigerant absorbent (62) can be configured by absorbing water with a polyacrylic acid-based or carboxymethylcellulose-based water-absorbing polymer.

Therefore, as shown in FIG. 6, even if the inner pipe (54) and the outer pipe (55) are damaged and cracks (56) and (57) are generated on the pipe wall, they are indicated by arrows in the figure. Similarly, when the refrigerant (82) intrudes from the crack (56) of the inner pipe (54) into the space between the inner pipe (54) and the outer pipe (55), the refrigerant is absorbed by the refrigerant absorbent (62). You. As a result, leakage of the refrigerant to the outside from the cracks (57) of the outer tube (55) is prevented.

Fourth Embodiment As shown in FIG. 7, the space between the inner tube (54) and the outer tube (55) is filled with an oxidizing agent (63) that causes an oxidation reaction with the refrigerant. Oxidant
(63) includes, for example, platinum group metals (Pt, Pd, Rh, etc.)
And an oxide of a base metal (Cr, Co, Ni, Mn, Fe, etc.).

Therefore, as shown in FIG. 8, even if the inner pipe (54) and the outer pipe (55) are damaged and cracks (56) and (57) are generated on the pipe wall, thick arrows in the figure indicate As shown, when the refrigerant (83) intrudes from the crack (56) of the inner pipe (54) between the inner pipe (54) and the outer pipe (55), the refrigerant is oxidized by the oxidizing agent (63). As a result, the substances generated by the oxidation leak out from the cracks (57) of the outer tube (55) as indicated by thin arrows in the figure. Here, when ammonia is used as the refrigerant (83), nitrogen and water are generated by oxidation, and when hydrocarbons are used as the refrigerant (83),
Oxidation only produces carbon dioxide and hydrogen,
No toxic or explosive harmful substances leak out.

Fifth Embodiment As shown in FIG. 9, a space between the inner pipe (54) and the outer pipe (55) is filled with a compressed carbon dioxide gas (64).

Therefore, as shown in FIG.
Even if the outer pipe (55) is damaged and cracks occur in the pipe wall, as shown by the thick arrow in the figure, the refrigerant (84) is
From the inner tube (54) and outer tube (55) through the crack (56)
Furthermore, as indicated by thin arrows in the figure, cracks in the outer tube (55)
When leaking to the outside from (57), the refrigerant (84) contains carbon dioxide gas (6
It is diluted by 4) and leaks to the outside together with carbon dioxide (64) in a safe state without toxicity or explosion.

Incidentally, between the inner pipe (54) and the outer pipe (55), carbon dioxide adsorbing carbon dioxide molecules instead of or together with the compressed carbon dioxide gas (64). It is also possible to adopt a configuration in which an agent (e.g., zeolite) or a carbon dioxide absorbent (e.g., lithium zirconate) that has absorbed carbon dioxide molecules is accommodated. In this case, carbon dioxide is released when the carbon dioxide adsorbent or the carbon dioxide absorbent becomes hot.

As described above, in the first to third embodiments, the structure for preventing the leakage of the refrigerant is employed, and in the fourth and fifth embodiments, the structure for making the leaking refrigerant harmless is employed. Therefore, even if the piping is broken, it is safe.

In order to identify the damaged part of the pipe, the outer pipe (55)
It is effective to arrange an intelligent material that changes color in response to a refrigerant or a crack on the outer peripheral surface of the device.

[Brief description of the drawings]

FIG. 1 is a sectional view of a pipe employed in a first embodiment of the present invention.

FIG. 2 is an enlarged sectional view illustrating an operation when the pipe is broken.

FIG. 3 is a sectional view of a pipe employed in a second embodiment of the present invention.

FIG. 4 is an enlarged sectional view illustrating an operation when the pipe is broken.

FIG. 5 is a sectional view of a pipe employed in a third embodiment of the present invention.

FIG. 6 is an enlarged cross-sectional view illustrating an operation when the pipe is broken.

FIG. 7 is a sectional view of a pipe employed in a fourth embodiment of the present invention.

FIG. 8 is an enlarged sectional view illustrating an operation when the pipe is broken.

FIG. 9 is a sectional view of a pipe employed in a fifth embodiment of the present invention.

FIG. 10 is an enlarged sectional view illustrating an operation when the pipe is broken.

FIG. 11 is a system diagram illustrating a configuration of a compression refrigerator.

FIG. 12 is a P (pressure) -i (enthalpy) diagram showing a refrigeration cycle.

[Explanation of symbols]

 (54) Inner tube (55) Outer tube (6) Rapid fixative (61) Electrorheological fluid (62) Refrigerant absorbent (63) Oxidant (64) Carbon dioxide (8) Refrigerant

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Tetsuya Masuda 2-5-5 Keihanhondori, Moriguchi-shi, Osaka Sanyo Electric Co., Ltd. (72) Takashi Yamakawa 2-5-2 Keihanhondori, Moriguchi-shi, Osaka No. 5 Sanyo Electric Co., Ltd.

Claims (10)

[Claims] 1. A compression type refrigerating machine in which an evaporator (1), a compressor (2), a condenser (3) and a throttle valve (4) are connected to each other by piping to circulate the refrigerant. Has a double-walled structure consisting of an inner pipe (54) and an outer pipe (55), and solidifies rapidly between the inner pipe (54) and the outer pipe (55) by contact with outside air. A compression refrigerator characterized by being filled with a quick fixing agent (6). 2. The compression refrigerator according to claim 1, wherein the quick fixing agent is filled at a pressure higher than the outside air pressure. 3. A compression type refrigerator in which an evaporator (1), a compressor (2), a condenser (3) and a throttle valve (4) are connected to each other by piping to circulate the refrigerant. The entire length or a part of it is a double pipe structure consisting of an inner pipe (54) and an outer pipe (55), and an electrorheological fluid that is solidified by applying voltage between the inner pipe (54) and the outer pipe (55). While filling (61), the pipe wall
A pair of electrodes (73) and (73) are arranged on both sides of the electrorheological fluid (61), and when leakage of refrigerant is detected, the pair of electrodes
(73) A compression refrigerator having a predetermined voltage applied to (73). 4. A pressure sensor (7) for detecting the pressure of a refrigerant (81) or an electrorheological fluid (61), and when the pressure sensor (7) detects a pressure fluctuation exceeding a threshold value, 4. The compression refrigerator according to claim 3, further comprising a drive circuit for applying a predetermined voltage to the electrodes (73). 5. A compression type refrigerator in which an evaporator (1), a compressor (2), a condenser (3), and a throttle valve (4) are connected to each other by piping to circulate the refrigerant. The entire length or a part of the inner pipe (54) and the outer pipe (55) has a double-pipe structure, between the inner pipe (54) and the outer pipe (55), filled with a refrigerant absorbent (62) A compression refrigerator comprising: 6. The refrigerant is ammonia, and the refrigerant is a refrigerant absorbent.
The compression refrigerator according to claim 5, wherein (62) is made of a water-absorbing polymer containing water. 7. A compression type refrigerator in which an evaporator (1), a compressor (2), a condenser (3), and a throttle valve (4) are connected to each other by piping to circulate the refrigerant. The entire length or a part of the inner pipe (54) and the outer pipe (55) has a double pipe structure, and between the inner pipe (54) and the outer pipe (55), an oxidizing agent ( 63) A compression type refrigerator characterized by being filled with: 8. The compression refrigerator according to claim 7, wherein the oxidizing agent (63) is an oxide of a platinum group metal or a base metal. 9. A compression type refrigerator in which an evaporator (1), a compressor (2), a condenser (3) and a throttle valve (4) are connected to each other by piping to circulate the refrigerant. That the entire length or part of the tube has a double pipe structure consisting of an inner pipe (54) and an outer pipe (55), and that a carbon dioxide gas source is placed between the inner pipe (54) and the outer pipe (55). Characteristic compression refrigerator. 10. The compression system according to claim 9, wherein the carbon dioxide gas generation source is a compressed carbon dioxide gas, a carbon dioxide adsorbent that has absorbed carbon dioxide molecules, or a carbon dioxide absorbent that has absorbed carbon dioxide molecules. refrigerator.