JP2000234587A - Air compressor and gas separating device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the cooling efficiency of a cooling line to cool compressed air discharged from an air compressor. SOLUTION: A nitrogen generating device 10 forms a package type wherein an air compressor 12, an auto drain trap 14, an air filter 16, and a nitrogen generating part are contained in one and the same casing. An air compressor 12 comprises a reciprocation type compressor 20; an air tank 22; and an after- cooler 24 to cool compressed air discharged from the air tank 22. The after- cooler 24 is formed that a fin tube 28 is contained in a cooling chamber 26, and a blast fan 32 to generate an air flow for cooling to the fin tube 28 is arranged in the upper exhaust port 30 of the cooling chamber 26. The fin tube 28 is bent in an inverted U-shape and cooling performance is improved. A large number of radiation fins are arranged at intervals of a given distance on the outer periphery of the fin tube 28.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an air compressor and a gas separation device configured to remove moisture contained in compressed air.

[0002]

2. Description of the Related Art In general, in an air compressor, air is sucked, compressed and discharged to an air tank. Therefore, moisture contained in air together with compressed air is stored as moisture in the air tank. And when the temperature of the air tank drops,
Water contained in the compressed air is condensed on the inner wall of the air tank, and water drops accumulate on the bottom of the air tank.

[0003] As described above, in the method of removing the moisture contained in the compressed air by utilizing the decrease in the temperature of the air tank, it takes time until the temperature of the air tank falls, and the compressed air is continuously supplied to downstream equipment. In this case, the compressed air is supplied without being dehumidified, and it is not possible to supply the compressed air to a device that dislikes moisture. As an apparatus to which compressed air is supplied from the air compressor as described above, for example, there is a gas separation device having a gas separation membrane for separating air into a product gas and a gas other than the product gas. As a gas separation device, a nitrogen generation device incorporating a gas separation membrane for separating air into oxygen and nitrogen and extracting nitrogen as a product gas is being developed.

[0004] Therefore, an after-cooler (cooling unit) for cooling a cooling pipe line through which the compressed air passes is provided in the air compressor to cool the compressed air discharged from the air compressing unit, and then is cooled by an auto drain trap (drain unit). A method of removing water contained in compressed air as water droplets and then dehumidifying with a film dryer has been studied.

[0005]

However, if the cooling by the aftercooler is insufficient and the cooling of the compressed air proceeds downstream of the auto drain trap, dew condensation may occur in the compressed air. In this case, if dew condensation occurs in a device such as a nitrogen generator provided on the downstream side of the auto drain trap, a problem such as a decrease in performance of the gas separation membrane occurs.

[0006] Further, in the film-type dryer, there is a problem that the life of the film-type dryer is reduced if water droplets adhere during dehumidification. In the case of a device that continuously consumes compressed air generated by an air compressor, such as a nitrogen generator, it is necessary to enhance the cooling performance of the aftercooler according to the supply flow rate of the compressed air.

In the conventional apparatus, if the length of the cooling pipe of the aftercooler is extended, the cooling efficiency of the aftercooler can be improved, but the mounting space in the housing must be increased. However, in a so-called package-type air compressor and a nitrogen generator in which an air compressor, an air tank, a nitrogen generator, and the like are housed in a housing, there is a limit to a space for mounting an aftercooler with the downsizing of the housing. Therefore, in the conventional apparatus, when the entire length of the cooling pipe of the aftercooler is extended in order to enhance the cooling performance of the aftercooler, there is a problem that the aftercooler itself needs to be large and the casing must be large.

Accordingly, an object of the present invention is to provide an air compressor and a gas separation device which solve the above-mentioned problems.

[0009]

In order to solve the above problems, the present invention has the following features. Claim 1
The described invention, an air compression unit that generates compressed air, a cooling unit that cools the compressed air discharged from the air compression unit,
In an air compressor having a housing accommodating the air compression unit and the cooling unit, and a drain removing unit for removing water liquefied by the cooling unit, the cooling unit is configured to suck cooling air in the housing. A cooling chamber formed between the suction port and the exhaust port from which the cooling air is exhausted, and a blower fan provided in the cooling chamber and exhausting the cooling air sucked from the suction port from the exhaust port, A cooling pipe which extends in a direction from the suction port to the exhaust port and through which compressed air discharged from the air compression section passes.

Therefore, according to the first aspect of the present invention, the cooling section is compressed in the cooling chamber formed between the suction port in the casing where the cooling air is sucked and the exhaust port where the cooling air is exhausted. Since a cooling pipe through which air passes is provided, and a blower fan that exhausts cooling air sucked from a suction port of the cooling chamber through an exhaust port is provided, cooling performance of the cooling pipe can be improved.

According to a second aspect of the present invention, there is provided the air compressor according to the first aspect, wherein the blower fan is provided at the exhaust port, and the suction port is provided at the inlet of the cooling pipe. Characterized by being provided at a position close to the side. Therefore, according to the second aspect of the present invention, the blower fan is provided at the exhaust port, and the suction port is provided at a position close to the inflow side of the cooling pipeline.
The airflow generated by the blower fan can be blown more toward the inflow side of the cooling line, and even when using a small-sized fan with small capacity, the inflow side of the cooling line with the highest temperature is mainly cooled. Can be. Therefore, even when the airflow generated by the blower fan is limited,
While the outside air flowing in from the suction port moves along the direction in which the cooling pipeline extends, the cooling pipeline can be efficiently cooled from the inflow side.

According to a third aspect of the present invention, there is provided the air compressor according to the first aspect, wherein the cooling pipe has an inlet side and an outlet side of the cooling pipe from the suction port to the exhaust port. It is characterized by being folded back in a U-shape so as to extend in the direction toward it. Therefore, according to the third aspect of the present invention, the cooling pipe is folded in a U-shape so that both the inflow side and the outflow side of the cooling pipe extend in the direction from the suction port to the exhaust port. In addition, the entire length of the cooling pipeline can be extended within a limited installation space, and the cooling performance of the cooling pipeline can be enhanced.

According to a fourth aspect of the present invention, in the air compressor according to the second aspect, the U-shaped bent portion of the cooling pipe is inclined at a predetermined angle toward the inner wall of the cooling chamber. It is characterized by the following. Therefore, according to the fourth aspect of the present invention, since the U-shaped bent portion of the cooling pipe is inclined at a predetermined angle toward the inner wall side of the cooling chamber, the cooling efficiency of the U-shaped bent portion can be increased.

According to a fifth aspect of the present invention, there is provided the air compressor according to the third aspect, wherein the suction port is located at a position close to an inflow side of the cooling line and an outflow side of the cooling line. Is provided at a position close to the end of the. Therefore, according to the fifth aspect of the present invention, since the suction port is provided at a position close to the inflow side of the cooling pipe line and at a position close to the outflow side end of the cooling pipe line, air generated by the blower fan is provided. The flow can be blown more to the inflow side and the outflow side end of the cooling pipeline, and even if the blowing fan is small in size and small, the cooling pipeline bent in a U-shape can be efficiently cooled. can do.

According to a sixth aspect of the present invention, a gas separation membrane for separating air into a product gas and a gas other than the product gas and an air compressor are provided in a housing, and the air compressor is provided on the gas separation membrane. In a gas separation device for supplying compressed air from an air tank and extracting product gas from the gas separation membrane, a suction port provided in the housing and for sucking cooling air and an exhaust port for discharging cooling air are provided. A cooling pipe formed between the cooling chamber and the cooling chamber, and extending in a direction from the suction port to the exhaust port of the cooling chamber, and through which compressed air discharged from the air compressor passes. And a blower fan that is provided at the mouth and blows cooling air to the cooling pipe line.

According to the sixth aspect of the present invention, the cooling unit is compressed in the cooling chamber formed between the suction port in the casing where the cooling air is sucked and the exhaust port where the cooling air is exhausted. The cooling performance of the cooling pipeline can be improved because the cooling pipeline through which the air passes is provided and the blower fan is provided at the exhaust port of the cooling chamber. The invention according to claim 7 is
7. The gas separation device according to claim 6, wherein the cooling pipe is formed in a U-shape such that both the inflow side and the outflow side of the cooling pipe extend in a direction from the suction port to the exhaust port. It is characterized by being folded back to.

Therefore, according to the present invention, the cooling pipe is formed in a U-shape such that both the inflow side and the outflow side of the cooling pipe extend in the direction from the suction port to the exhaust port. Due to the turning back, the entire length of the cooling pipeline can be extended within the limited mounting space, and the cooling performance of the cooling pipeline can be enhanced.

[0018]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a system diagram showing a configuration of an embodiment of an air compressor and a gas separation device according to the present invention. As shown in FIG. 1, a nitrogen generator 10 as a gas separation device includes an air compressor 12, an auto drain trap (drain removing unit) 14, an air filter 16, and a nitrogen generator 18 in the same housing. It has a packaged configuration housed inside the body.

The air compressor 12 includes a reciprocating compressor 20 that reciprocates while oscillating a piston, an air tank 22 that stores compressed air generated by the reciprocating compressor 20, and an air tank 22. And an aftercooler (cooling unit) 24 for cooling the discharged compressed air. The aftercooler 24 accommodates a fin tube (cooling conduit) 28 in a cooling chamber 26 formed as described later,
A blower fan 32 for generating a cooling airflow to the fin tube 28 is provided at an upper exhaust port 30 of the fin tube 28. When the blower fan 32 is driven to rotate, the cooling chamber 26
The air inside is exhausted to the outside through the exhaust port 30 and the cooling chamber 26
Becomes negative pressure. Therefore, outside air is introduced from the suction port 34 located below the cooling chamber 26, and the fin tube 28 is cooled by air cooling. Thus, the blower fan 3
Since 2 is provided on the exhaust side, it is possible to generate a negative pressure in the cooling chamber 26 to replace the air inside the entire cooling chamber 26, thereby cooling the fin tube 28 over the entire length.

The auto drain trap 14 separates and removes water condensed in the compressed air cooled by the aftercooler 24, and includes two drain filters 35 and a membrane-type membrane dryer 36 in series. It is connected to the. Then, the compressed air that has passed through the auto drain trap 14 is introduced into the air filter 16 to remove foreign substances contained in the compressed air. The air filter 16 is provided with an air release valve 37 that opens when the compressed air is released into the atmosphere.

The nitrogen generating section 18 includes a discharge solenoid valve 38 on the inflow side connected to the air filter 16 and an air filter 16.
Separation membrane 39 to which compressed air is supplied, pressure reducing valve 40 for reducing the pressure of nitrogen gas as a product gas discharged from nitrogen separation membrane 39, and oxygen concentration of nitrogen gas separated and generated by nitrogen separation membrane 39 , A check valve 44, and a discharge solenoid valve 46 for discharging nitrogen gas.

The nitrogen separation membrane 39 is composed of a membrane module filled with a large number of hollow fibers. When compressed air is supplied to the membrane module, the nitrogen separation membrane 39 separates the inner wall of the hollow fiber into oxygen that easily permeates and nitrogen that hardly permeates. I do. Therefore, oxygen contained in the compressed air is discharged from the nitrogen separation membrane 39 to the outside. The nitrogen contained in the compressed air passes through the fine internal passage of the hollow fiber and is discharged to the outside by the opening operation of the discharge solenoid valve 46.

FIG. 2 is a perspective view showing a state where the front panel of the nitrogen generator 10 is removed. FIG. 3 is a perspective view showing a state in which a rear panel of the nitrogen generator 10 is removed.
As shown in FIGS. 2 and 3, the housing 48 of the nitrogen generator 10 is formed of a box-shaped package, and a front panel 50 is attached to the front side so as to be openable and closable. Case 48
Is defined by a partition 52 into a compressor chamber 53 and a nitrogen generation chamber 54. Further, a partition plate 56 for defining the cooling chamber 26 is attached to a side surface of the nitrogen generating chamber 54.

The compressor chamber 53 is located on the front side of the housing 48 and has an air tank 22 on the bottom surface. The reciprocating compressor 20 supported by a bracket 55 is mounted on the upper part of the air tank 22. Have been. The reciprocating compressor 20 includes:
It has piston-cylinder mechanisms on both the left and right sides, and filters 20a and 20b for filtering air sucked into the cylinder are provided on the front side of the reciprocating compressor 20.
Then, the casings 48 located on both sides of the reciprocating compressor 20
Are provided with air inlets 23 on the left and right sides.

A part of the air sucked from the air suction port 23 becomes the raw material air compressed by the reciprocating compressor 20, and the remaining air is an exhaust port 49 provided on the upper surface 48 a of the housing 48. From the compressor to cool the reciprocating compressor 20. A digitally displayed oximeter 51, a start switch 57, and an operation counter 58
Is attached. A reset switch 59 is mounted on the front surface of the bracket 55.

The discharge pipe 60 of the air tank 22 is connected to a pressure sensor 61 provided in the compressor chamber 53. The pressure sensor unit 61 includes a pressure gauge 62 that measures the pressure of the compressed air discharged from the air tank 22 and a pressure switch 64 that operates when the pressure of the compressed air discharged from the air tank 22 becomes abnormal. And The pipe 66 drawn from the pressure sensor unit 60 is J
It is bent in the shape of a letter, and its end is drawn out to the cooling chamber 26 through the partition wall 52.

Since the nitrogen generating chamber 54 and the cooling chamber 26 are isolated from the compressor chamber 53 by the partition wall 52, the heat generated by the reciprocating compressor 20 is insulated, and the reciprocating compressor 20 is insulated. The heat generated by the heat generator 20 prevents the nitrogen separation membrane 39 housed in the nitrogen generation chamber 54 and the fin tube 28 housed in the cooling chamber 26 from being heated. FIG. 4 is a rear view showing the internal configuration of the nitrogen generator 10 with the rear panel removed.

As shown in FIG. 4, a cooling chamber 26 defined by a partition plate 56 is formed between the nitrogen generating chamber 54 and the side surface of the casing so as to extend in the vertical direction. The exhaust port 30 of the cooling chamber 26 is provided on an upper surface 48 a of the housing 48, and the suction port 34 is provided on a left side surface 48 b of the housing 48. The fin tube 28 is attached so as to extend from the suction port 34 in the space of the cooling chamber 26 toward the exhaust port 30.

FIG. 5 is a perspective view showing the external shape of the fin tube 28. FIG. As shown in FIG. 5, the fin tube 28 includes an inverted U-shaped folded portion 28a and an inflow side straight portion 28b extending downward from one end of the folded portion 28a.
And an outflow-side straight portion 28c extending downward from the other end of the folded portion 28a. Then, the folded portion 28a,
On the outer periphery of the inflow side straight portion 28b and the outflow side straight portion 28c,
A large number of radiation fins 28d are provided at predetermined intervals.

As described above, the fin tube 28 is
Since it is bent in a letter shape, it has a compact configuration, and its overall length is increased even in a narrow space to improve cooling performance. Therefore, the fin tube 28 can contribute to downsizing of the device by reducing the mounting space, and also can improve the cooling efficiency and efficiently remove the moisture contained in the compressed air, thereby affecting the downstream equipment. Can be suppressed.

In the fin tube 28, the folded portion 28a is inclined toward the inside of the housing by a predetermined angle α with respect to the extending direction (vertical direction) of the inflow-side linear portion 28b and the outflow-side linear portion 28c. As shown in FIG. 4, a blower fan 32 is attached below the exhaust port 30. Then, when the blower fan 32 is driven, the inside of the cooling chamber 26 becomes a negative pressure, and outside air is introduced into the cooling chamber 26 from the suction port 34. The air introduced from the suction port 34 of the cooling chamber 26 moves along the inflow-side linear portion 28b and the outflow-side linear portion 28c, and then passes around the folded portion 28a that is inclined inside the housing. Then, the air is exhausted from the exhaust port 30 to the outside.

As a result, the fin tube 28 is cooled by the airflow passing around the radiation fin 28d, and is separated from the inflow side straight portion 28b and the outflow side straight portion 28c because the folded portion 28a is inclined. The folded portion 28a is cooled by the unheated airflow flowing through the place. Therefore, the cooling efficiency of the fin tube 28 is enhanced over the entire length, and the fin tube 28 can sufficiently cool the compressed air discharged from the air tank 22.

The compressed air that has passed through the fin tube 28 and cooled has water droplets condensed removed by the auto drain 14 provided on the left side surface 48b of the housing 48, and then the right side surface 48c of the housing 48 Air filter 1 provided in
6 removes foreign matter. Then, the air filter 16
Is passed through the tube 68 to the partition wall 52.
Is supplied to a lower portion (inflow side) of the nitrogen separation membrane 39 via a tube 69 by the opening operation of the discharge electromagnetic valve 38.

The nitrogen separation membrane 39 separates the compressed air into oxygen and nitrogen, exhausts oxygen to the outside, and releases nitrogen through a tube 70 connected to the upper part (outflow side).
0, supply to the discharge solenoid valve 46. And the discharge solenoid valve 4
The nitrogen separated by the nitrogen separation membrane 39 by the valve opening operation of No. 6 is discharged as a product gas. In addition, the nitrogen generation chamber 54
A terminal box 72 in which an electric circuit such as a control circuit for controlling each device is housed is mounted on the upper part of the terminal box 72.

FIG. 6 is a side view showing the left side of the nitrogen generator 10. As shown in FIG. 6, a caster (wheel) 74 for movement is attached to the bottom of the left side surface 48b of the housing 48. The suction port 34 of the cooling chamber 26 provided on the left side surface 48b of the housing 48 is a set of small rectangular openings, and includes three suction rows 34a to 34c. The suction line 34a arranged on the left side has four openings, and the suction lines 34b and 34c arranged on the middle and right sides.
Has 22 openings.

The short suction line 34a on the left side is in close proximity to the end of the outflow side linear portion 28c of the fin tube 28, and the middle suction line 34b is the inflow side linear portion 28c of the fin tube 28.
The suction row 34b on the right side is located between the b and the outflow-side linear portion 28c, and is closely opposed to the inflow-side linear portion 28b of the fin tube 28. Therefore, in the fin tube 28 formed in an inverted U shape, the inflow-side straight portion 28b is more strongly cooled. In this way, the cooling efficiency of the inflow-side linear portion 28b having a high temperature can be increased by the shape of the suction port 34 (the arrangement pattern of the openings). Thus, the cooling performance of the fin tube 28 can be improved.

As described above, in the present embodiment, the suction port 3
4 is formed such that the opening area becomes large at a position close to the inflow side of the fin tube 28, so that the airflow generated by the blower fan 32 is blown more toward the inflow side straight portion 28b of the fin tube 28. Have been. Therefore, even if the blower fan 32 is small and small, the fin tube 28 having the highest temperature is used.
Of the inflow side linear portion 28b can be mainly cooled. Therefore, even when the airflow generated by the blower fan 32 is limited, the outside air flowing in from the suction port 34 moves along the extending direction (upward) of the fin tube 28 and moves the fin tube 28 from the inflow side. It can be cooled efficiently. Therefore, when the blower fan 32 is driven, the amount of air suction from the suction rows 34a is small, the amount of air suction from the suction rows 34b and 34c is large, and the amount of air supplied to the high-temperature inflow-side linear portion 28b is reduced. In many cases, the amount of air supply to the outflow-side linear portion 28c having a low temperature is reduced.

Although the above embodiment has been described using a nitrogen generator, the present invention is not limited to this, and it goes without saying that the present invention can be applied to a gas separator such as an oxygen generator.

[0039]

As described above, according to the first aspect of the present invention, the cooling section is formed between the suction port in the casing where the cooling air is sucked and the exhaust port where the cooling air is exhausted. Since the cooling chamber is provided with a cooling pipe through which the compressed air passes, and a cooling fan for exhausting the cooling air sucked from the suction port of the cooling chamber through the exhaust port, the cooling performance of the cooling pipe can be improved. Therefore, the total length of the cooling pipeline can be shortened, and the space for mounting the cooling pipeline can be reduced, which can contribute to downsizing of the device.

According to the second aspect of the present invention, since the suction port is provided at a position close to the inflow side of the cooling pipeline, the airflow generated by the blower fan is blown more toward the inflow side of the cooling pipeline. Therefore, even when a small blower fan having a small capacity is used, the inflow side of the cooling pipe having the highest temperature can be mainly cooled. Therefore, even when the airflow generated by the blower fan is limited, the outside air flowing in from the suction port moves along the extending direction of the cooling pipe while efficiently cooling the cooling pipe from the inflow side. Can be.

According to the third aspect of the present invention, the cooling pipe is formed in a U-shape such that both the inflow side and the outflow side of the cooling pipe extend in the direction from the suction port to the exhaust port. Due to the turning back, the entire length of the cooling pipeline can be extended within the limited mounting space, and the cooling performance of the cooling pipeline can be enhanced. Therefore, even if the entire length of the cooling pipe is extended, a compact configuration can be achieved, and as a result, the space for mounting the cooling pipe can be reduced, which can contribute to downsizing of the apparatus.

According to the fourth aspect of the invention, since the U-shaped bent portion of the cooling pipe is inclined at a predetermined angle toward the inner wall of the cooling chamber, the cooling efficiency of the U-shaped bent portion can be increased. . Therefore, the cooling pipe can be made compact and the cooling performance can be improved. According to the fifth aspect of the present invention,
Since the suction port is provided at a position close to the inflow side of the cooling pipe and at a position close to the end of the cooling pipe at the outflow side, the airflow generated by the blower fan is reduced to the inflow side and the outflow side of the cooling pipe. The cooling fan can be efficiently blown into the U-shaped cooling pipe even if the blowing fan is small in size.

According to the sixth aspect of the present invention, the cooling portion is compressed in the cooling chamber formed between the suction port in the casing where the cooling air is sucked and the exhaust port where the cooling air is exhausted. The cooling performance of the cooling pipeline can be improved because the cooling pipeline through which the air passes is provided and the blower fan is provided at the exhaust port of the cooling chamber. Therefore, in the gas separation device,
This makes it possible to shorten the entire length of the cooling pipeline, and to reduce the mounting space for the cooling pipeline, thereby contributing to downsizing of the apparatus.

According to the seventh aspect of the present invention, the cooling pipe is formed in a U-shape such that both the inflow side and the outflow side of the cooling pipe extend in the direction from the suction port to the exhaust port. Due to the turning back, the entire length of the cooling pipeline can be extended within the limited mounting space, and the cooling performance of the cooling pipeline can be enhanced. Therefore, also in the gas separation device, a compact configuration can be achieved while extending the entire length of the cooling line, and as a result, the space for mounting the cooling line can be reduced, which can contribute to downsizing of the device.

[Brief description of the drawings]

FIG. 1 is a system diagram showing the configuration of an embodiment of an air compressor and a gas separation device according to the present invention.

FIG. 2 is a perspective view showing a state where a front panel of the nitrogen generator 10 is removed.

FIG. 3 is a perspective view showing a state where a rear panel of the nitrogen generator 10 is removed.

FIG. 4 is a rear view showing the internal configuration of the nitrogen generator 10 with a rear panel removed.

FIG. 5 is a perspective view showing an external shape of the fin tube 28.

FIG. 6 is a side view showing the left side surface of the nitrogen generator 10.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Nitrogen generator 12 Air compressor 14 Auto drain trap 16 Air filter 18 Nitrogen generator 20 Reciprocating compressor 22 Air tank 24 Aftercooler 26 Cooling room 28 Fin tube 30 Exhaust port 32 Ventilation fan 34 Suction port 35 Drain filter 36 Membrane Dryer 39 Nitrogen separation membrane 42 Oxygen sensor 48 Housing 50 Front panel 52 Partition wall 53 Compressor room 54 Nitrogen generation room 56 Partition plate 61 Pressure sensor

Claims (7)

[Claims] An air compression unit for generating compressed air; a cooling unit for cooling compressed air discharged from the air compression unit;
In an air compressor having a housing accommodating the air compression unit and the cooling unit, and a drain removal unit for removing water liquefied by the cooling unit, the cooling unit is configured to suck cooling air in the housing. A cooling chamber formed between a suction port to be cooled and an exhaust port from which cooling air in the housing is exhausted, and cooling air provided in the cooling chamber and sucked from the suction port, is exhausted from the exhaust port. An air compressor, comprising: a blower fan; and a cooling pipe formed to extend in a direction from the suction port to the exhaust port and through which compressed air discharged from the air compressor passes. 2. The air compressor according to claim 1, wherein the blower fan is provided at the exhaust port, and the suction port is provided at a position close to an inflow side of the cooling pipe line. An air compressor characterized in that: 3. The air compressor according to claim 1, wherein the cooling pipe is formed such that an inflow side and an outflow side of the pipe both extend in a direction from the suction port to the exhaust port. An air compressor characterized by being folded back into a U-shape. 4. The air compressor according to claim 3, wherein a U-shaped bent portion of the cooling pipe is inclined at a predetermined angle toward an inner wall of the cooling chamber. 5. The air compressor according to claim 3, wherein the suction port is located at a position close to an inflow side of the cooling line and a position close to an end of the cooling line at an outflow side. An air compressor characterized by being provided. 6. A gas separation membrane for separating air into a product gas and a gas other than the product gas and an air compressor are provided in the housing,
In a gas separation device for supplying compressed air from an air tank of the air compressor to the gas separation membrane and extracting product gas from the gas separation membrane, a suction port provided in the housing and for sucking cooling air. A cooling chamber formed between an exhaust port from which cooling air is exhausted, and a cooling air extending from the suction port of the cooling chamber toward the exhaust port, and compressed air discharged from the air compressor. A gas separation device comprising: a cooling pipe passing therethrough; and a blower fan provided at the exhaust port and blowing cooling air to the cooling pipe. 7. The gas separation device according to claim 4, wherein the cooling pipe is formed such that both the inflow side and the outflow side of the cooling pipe extend in a direction from the suction port to the exhaust port. Characterized in that it is folded back into a U-shape as described above.