JP2022051100A - Compressor - Google Patents

Abstract

To inhibit inflow of drainage into a compression part of a second stage compressor body and inhibit enlargement of a passage pipe in a compressor.SOLUTION: The compressor includes: a first stage compressor body 10 which compresses air; and a second stage compressor body which further compresses the air compressed by the first stage compressor body 10. A second stage compressor body 20 includes: a casing 23 provided with a suction port 21 and a discharge port 22; a compression part 24 which is provided in the casing 23, communicates with the discharge port 22, and compresses the air; and a separation part 25 which is provided in the casing 23, communicates with the suction port 21 and the compression part 24, and has a passage cross section area of a predetermined size to separate drainage from the air.SELECTED DRAWING: Figure 2

Description

The present invention relates to a compressor.

The compressed gas discharged from the compressor becomes hot due to the heat of compression. In particular, when compressing in two stages like a two-stage compressor, if the high-temperature compressed gas discharged from the first-stage compressor body is further compressed by the second-stage compressor body as it is, the compressed gas becomes extremely hot. , The compressor may be thermally damaged. Therefore, the compressed gas discharged from the first-stage compressor body is often further compressed by the second-stage compressor body after being cooled.

When the high-temperature compressed gas discharged from the first-stage compressor main body is cooled, the water content in the compressed gas is condensed and drainage is generated. If the drain flows into the compressed portion of the second stage compressor body, the compressed portion may be rusted, so that the drain needs to be removed.

Patent Document 1 discloses a two-stage compressor having a first-stage compressor main body and a second-stage compressor main body. An intercooler is arranged between the first-stage compressor main body and the second-stage compressor main body, and the compressed air is cooled by the intercooler. At this time, drainage may occur in the intercooler, but by securing a large cross-sectional area of the flow path of the compressed air and reducing the flow velocity of the compressed air, the drain rides on the flow of the compressed air and drains from the second stage compressor body. It suppresses the inflow to the compressed part.

Japanese Unexamined Patent Publication No. 2002-21759

As in Patent Document 1, if a large cross-sectional area of the compressed air flow path is secured, the flow path piping becomes large. Along with this, the degree of freedom in flow path design is reduced, it becomes necessary to secure a large installation space, which leads to an increase in cost.

An object of the present invention is to suppress the inflow of drain into the compression portion of the main body of the second-stage compressor and to suppress the increase in size of the flow path piping in the compressor.

The present invention includes a first-stage compressor main body that compresses gas and a second-stage compressor main body that further compresses the gas compressed by the first-stage compressor main body, and the second-stage compressor main body is provided. A casing provided with an intake port and a discharge port, a compression unit provided in the casing and communicating with the discharge port to compress the gas, and a compression unit provided in the casing and the intake port and the compression unit. Provided is a compressor including a separating portion having a flow path cross-sectional area of a predetermined size for communicating and separating the drain from the gas.

According to this configuration, in the second-stage compressor main body, the drain can be separated from the compressed gas by the separating portion, so that the inflow of the drain into the compression portion can be suppressed. In particular, since the second-stage compressor body itself has a separation portion, it is not necessary to reduce the flow velocity in the flow path piping. That is, even if the drain flows into the second-stage compressor main body, the drain can be separated and removed in the second-stage compressor main body. Therefore, the size of the flow path cross-sectional area of the flow path pipe can be freely designed, and the increase in size of the flow path pipe can be suppressed.

The separation portion may be arranged below the compression portion.

According to this configuration, the inflow of the drain into the compressed portion can be further suppressed. At the separation part, the drain falls under its own weight, and the drain is separated from the gas. Therefore, the drain that falls at the separation portion moves in the direction away from the compression portion, so that the inflow of the drain into the compression portion can be further suppressed.

The predetermined size of the flow path cross-sectional area of the separation portion may be a size that makes the flow velocity of the gas equal to or lower than the terminal velocity in the cross section perpendicular to the vertical direction.

According to this configuration, the flow velocity of the gas at the separation part is set to the terminal velocity (the maximum velocity reached in balance with the air resistance when the droplet freely falls in the air), so that the drain can flow against the gas flow. Can fall. Therefore, the drain can be separated from the gas without the drain flowing into the compression portion. The terminal velocity may be set to, for example, about 5 m / sec.

The separated portion may be cylindrical with a central axis, and the intake direction of the intake port with respect to the separated portion is not directed to the central axis but is directed to the inner surface of the cylindrical shape constituting the separated portion. May be.

According to this configuration, the gas flows along the cylindrical inner surface of the separation part. The drain contained in the compressed gas adheres to the inner surface by contact with the inner surface, and flows down along the inner surface. Therefore, the drain can be further separated from the gas, and the inflow of the drain into the compressed portion can be further suppressed.

The compression unit may be provided with a compression wall that defines a compression chamber inside, the compression wall may be provided with an introduction port for introducing the gas into the compression chamber, and the introduction port and the intake port may be provided. A non-direct view flow path structure that is not in a positional relationship that allows direct view of each other may be provided.

According to this configuration, the non-direct view flow path structure can prevent the compressed gas containing the drain introduced from the intake port from flowing directly (linearly) to the introduction port. Therefore, the inflow of the drain into the compressed portion can be further suppressed.

The non-direct view flow path structure may have an obstacle plate that obstructs the flow of the gas linearly from the intake port to the introduction port between the introduction port and the intake port.

According to this configuration, the compressed gas including the drain taken in from the intake port collides with the baffle plate, and the drain adheres to the baffle plate. Then, the drain is separated from the compressed gas so as to flow down along the obstruction plate. Therefore, the inflow of the drain into the compressed portion can be further suppressed.

A storage portion for storing the drain separated by the separation portion may be formed in the casing.

According to this configuration, the drain can be recovered from the storage unit. Therefore, the amount of drain can be controlled, and the collected drain can be utilized as needed.

A perforated plate may be provided between the separation portion and the storage portion.

According to this configuration, it is possible to prevent the drain stored in the storage portion from being lifted by the perforated plate along with the flow of gas, so that the inflow of the drain into the compression portion can be further suppressed.

The reservoir may have corrosion resistance against the drain.

According to this configuration, it is possible to prevent the reservoir from being corroded by rust or the like due to drainage. The casing of the compressor is often made of cast metal, and the drain may cause corrosion such as rust. Therefore, a corrosion resistant structure is effective. Specifically, in order to impart corrosion resistance to the reservoir, a paint having corrosion resistance may be applied to the inner surface of the reservoir. Further, the inner surface of the reservoir may be coated with a material having corrosion resistance such as stainless steel.

A part of the casing in which the storage portion is formed may be configured to be detachably attached to the casing provided with the compression portion.

This configuration facilitates replacement of the reservoir. Further, since the storage portion can be made of a material different from that of the compression portion, corrosion resistance can be easily imparted to the storage portion.

A part of the removable casing may have corrosion resistance to the drain at least in the reservoir.

According to this configuration, it is possible to prevent the reservoir from being corroded by rust or the like due to drainage, as described above.

According to the present invention, in the compressor, it is possible to suppress the inflow of drain into the compression portion of the second-stage compressor main body and to suppress the increase in size of the flow path pipe.

The schematic block diagram of the compressor which concerns on one Embodiment of this invention. The first sectional view of the 2nd stage compressor main body. The second sectional view of the 2nd stage compressor main body. The cross-sectional view of the 2nd stage compressor main body in the 1st modification. The cross-sectional view of the 2nd stage compressor main body in the 2nd modification. The cross-sectional view of the 2nd stage compressor main body in the 3rd modification. The cross-sectional view of the 2nd stage compressor main body in the 4th modification.

Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

The compressor of this embodiment is an oil-free two-stage screw compressor. As the handling gas, air will be described below as an example.

With reference to FIG. 1, the compressor 1 has a first-stage compressor main body 10 and a second-stage compressor main body 20. In the present embodiment, the first-stage compressor main body 10, the intercooler 2, the second-stage compressor main body 20, and the aftercooler 3 are arranged in this order in the air flow path. These are fluidly connected by the flow path pipes 4a to 4c.

The first-stage compressor main body 10 takes in air from the intake port 11 through the flow path pipe 4a opened to the atmosphere, compresses the air inside, and discharges the air from the discharge port 12. At this time, the compressed air discharged from the discharge port 12 is pressure-fed to the intake port 21 of the second-stage compressor main body 20 through the flow path pipe 4b.

An intercooler 2 is provided in the flow path pipe 4b that fluidly connects the first-stage compressor main body 10 and the second-stage compressor main body 20. In the intercooler 2, heat exchange is performed between the cooling liquid from the outside and the air in the flow path pipe 4b, and the air in the flow path pipe 4b is cooled. The air in the flow path pipe 4b before passing through the intercooler 2 has a high temperature of, for example, about 180 °, but the air in the flow path pipe 4b after passing through the intercooler 2 is cooled to, for example, about 40 °. Will be done. Therefore, appropriately cooled compressed air is supplied to the second-stage compressor main body 20.

The second-stage compressor main body 20 takes in compressed air from the intake port 21 through the flow path pipe 4b, compresses the air inside, and discharges the air from the discharge port 22. The compressed air discharged from the discharge port 22 is supplied to a supply destination such as a factory through the flow path pipe 4c.

An aftercooler 3 is provided in the flow path pipe 4c that fluidly connects the second-stage compressor main body 20 and the supply destination (not shown). In the aftercooler 3, heat exchange is performed between the cooling liquid from the outside and the air in the flow path pipe 4c, and the air in the flow path pipe 4c is cooled. The air in the flow path pipe 4c before passing through the aftercooler 3 has a high temperature of, for example, about 180 °, but the air in the flow path pipe 4c after passing through the aftercooler 3 is cooled to, for example, about 40 °. Will be done. Therefore, appropriately cooled compressed air is supplied to the supply destination.

In the above configuration, when the air in the flow path pipe 4b is cooled by the intercooler 2, the moisture in the air in the flow path pipe 4b is condensed and drainage is generated in the flow path pipe 4b. The drain flows into the second-stage compressor main body 20 along with the air flow, but in the present embodiment, the second-stage compressor main body 20 has a structure for removing the drain.

Hereinafter, the structure for removing the drain in the second-stage compressor main body 20 will be described. The first-stage compressor body 10 is a general oil-free screw type and does not have to have a structure for removing the drain shown below.

With reference to FIGS. 2 and 3, the second-stage compressor main body 20 has a casing 23, and a compression unit 24 and a separation unit 25 provided in the casing 23.

In the present embodiment, the casing 23 is made of a casting and is an integral member. The casing 23 is provided with an intake port 21 and a discharge port 22.

The compression portion 24 is an oil-free screw type and is a portion that compresses air. The compression unit 24 accommodates a pair of male and female screw rotors 24b pivotally supported by the rotary shaft member 24a. The rotary shaft member 24a is mechanically connected to a motor (not shown). The rotary shaft member 24a is rotated by a motor, and a pair of male and female screw rotors 24b are rotated accordingly to engage with each other to compress air.

The compression unit 24 has a compression wall 24c that defines a compression chamber R1 in which a pair of male and female screw rotors 24b are housed. The compression wall 24c is provided with an introduction port 24d for introducing air into the compression chamber R1 and an outlet port 24e for leading out air from the compression chamber R1. The introduction port 24d of the compression unit 24 communicates with the separation unit 25, which will be described later. The outlet 24e of the compression unit 24 communicates with the discharge port 22.

Inside the casing 23, on the outside of the compression wall 24c, a cooling unit 26 through which a cooling liquid for cooling the compression unit 24 flows is provided. The cooling unit 26 is provided in the vicinity of the discharge port 22 where the temperature tends to rise due to the heat of compression. The coolant can be, for example, water.

The separation portion 25 is a portion that separates the drain from the air. In the present embodiment, the separation portion 25 has a square cylinder shape extending in the vertical direction (vertical direction in FIGS. 2 and 3), and is arranged below the compression portion 24. A separation chamber R2 having a channel cross-sectional area of a predetermined size is provided inside the separation portion 25. The predetermined size of the flow path cross-sectional area of the separation chamber R2 is such that the flow velocity of air is equal to or less than the terminal velocity in the cross section perpendicular to the vertical direction. That is, the flow path cross section S is defined as the integrated value of the horizontal dimension D1 and the vertical dimension D2 of the separation chamber R2 in the cross section (S = D1 × D2), and the flow path cross section S is the flow velocity V of the air flowing upward. Is designed so that the terminal velocity is Vt or less (V ≦ Vt). Here, the relationship between the flow path cross-sectional area S and the flow velocity V is such that the flow velocity V decreases as the flow path cross-sectional area S increases. Further, the terminal velocity Vt means the maximum speed reached in balance with the air resistance when the droplet freely falls in the air, and may be set to, for example, about 5 m / sec.

Further, in the present embodiment, the second-stage compressor main body 20 is arranged below the separation unit 25 and has a storage unit 27 for storing the drain separated by the separation unit 25. The storage unit 27 is integrally configured with the separation unit 25 in the casing 23. The storage unit 27 has a bottomed cylindrical structure. The depth of the storage portion 27 is sufficiently deep from the intake port 21 so that drain can be stored. A discharge port 28 and a discharge valve 29 are provided at the bottom of the storage unit 27. Therefore, the drain valve 29 can be opened and the drain can be discharged from the discharge port 28 as needed.

The flow of air inside the second-stage compressor main body 20 will be described with reference to FIGS. 2 and 3.

When compressed air containing drain flows from the intake port 21 to the separation portion 25 (see the broken line and solid arrow A1), the drain drops by its own weight in the separation chamber R2, and the drain is separated from the compressed air (broken line arrow). See A2). The compressed air from which the drain is separated flows upward to the introduction port 24d of the compression unit 24 (see the solid line arrow A3). The air introduced from the introduction port 24d to the compression unit 24 (see the solid line arrow A4) flows to the outlet port 24e while being compressed by the compression unit 24 (see the solid line arrow A5). The air compressed by the compression unit 24 is led out from the outlet 24e (see the solid line arrow A6) and discharged from the discharge port (see the solid line arrow A7).

According to this embodiment, the following effects are exhibited.

In the second-stage compressor main body 20, the drain can be separated from the compressed gas by the separation unit 25, so that the inflow of the drain into the compression unit 24 can be suppressed. In particular, since the second-stage compressor body 20 itself has the separating portion 25, it is not necessary to reduce the flow velocity in the flow path pipe 4b. That is, even if the drain flows into the second-stage compressor main body 20, the drain can be separated and removed in the second-stage compressor main body 20. Therefore, the size of the flow path cross-sectional area of the flow path pipe 4b can be freely designed, and the increase in size of the flow path pipe 4b can be suppressed.

Further, since the separation portion 25 is arranged below the compression portion, the inflow of the drain into the compression portion 24 can be further suppressed. At the separation unit 25, the drain falls under its own weight, and the drain is separated from the gas. Therefore, the drain that falls at the separation unit 25 moves in a direction away from the compression unit 24, so that the inflow of the drain into the compression unit 24 can be further suppressed.

Further, since the flow velocity of the gas in the separation portion 25 is set to be equal to or lower than the terminal velocity, the drain can fall against the flow of the gas. Therefore, the drain can be separated from the gas without flowing into the compression unit 24.

Further, since the second stage compressor main body 20 has a storage unit, drain can be collected from the storage unit 27. Therefore, the amount of drain can be controlled, and the collected drain can be utilized as needed.

(First modification)
A first modification of the above embodiment will be described with reference to FIG. FIG. 4 corresponds to FIG. 3 showing the above embodiment.

In this modification, a non-direct view flow path structure is provided in which the introduction port 24d and the intake port 21 are not in a positional relationship in which they can be directly viewed from each other. The non-direct view flow path structure refers to a structure that prevents air from flowing directly (straightly) from the intake port 21 to the introduction port 24d.

The non-direct view flow path structure includes a baffle plate 25a that obstructs the flow of air directly (straightly) from the intake port 21 to the introduction port 24d between the introduction port 24d and the intake port 21.

In FIG. 4, the obstruction plate 25a has a substantially L-shape, and faces the upper plate 25b extending in the intake direction (see the broken line and the solid line arrow A1) above the intake port 21 in a direction orthogonal to the intake direction. It has a plate 25c. The upper plate 25b prevents air from flowing linearly from the intake port 21 to the introduction port 24d. Further, when the air including the drain taken in from the intake port 21 collides with the facing plate 25c, the drain adheres to the facing plate 25c and flows down to the storage unit 27 through the facing plate 25c.

According to this modification, the non-direct view flow path structure can prevent the compressed gas containing the drain introduced from the intake port 21 from directly (linearly) flowing to the introduction port 24d. Therefore, the inflow of the drain into the compression portion 24 can be further suppressed.

Alternatively, the non-direct view flow path structure may not include the baffle plate 25a. For example, a part of the second stage compressor main body 20 such as the compression unit 24 or the cooling unit 26 may be arranged between the intake port 21 and the introduction port 24d, or the introduction port 24d may be directly viewed from the intake port 21. You may simply design the positional relationship so that it cannot be done.

(Second modification)
A second modification of the above embodiment will be described with reference to FIG. FIG. 5 corresponds to FIG. 3 showing the above embodiment.

In this modification, a perforated plate 27a is provided between the separation portion 25 and the storage portion 27. The perforated plate 27a is a thin plate provided with many small holes. For example, the perforated plate 27a may be a member obtained by drilling a stainless plate such as a so-called punching metal.

The method of installing the perforated plate 27a is not particularly limited, and the perforated plate 27a may be fixed at a predetermined depth position of the storage unit 27, or simply placed on the bottom of the storage unit 27 so as to float when the drain is accumulated in the storage unit. It may be placed.

According to this modification, the drain stored in the storage unit 27 can be suppressed from being lifted by the perforated plate 27a due to the air flow, so that the inflow of the drain into the compression unit 24 can be further suppressed.

(Third modification example)
A third modification of the above embodiment will be described with reference to FIG. FIG. 6 corresponds to FIG. 2 showing the above embodiment.

In this modification, the storage unit 27 has corrosion resistance against drainage. As described above, since the casing 23 is a casting, the drain may cause corrosion such as rust. On the other hand, in this modification, since the storage unit 27 has corrosion resistance against drainage, it is possible to suppress the occurrence of corrosion such as rust in the storage unit 27.

In order to impart corrosion resistance to the reservoir 27, a paint having corrosion resistance may be applied to the inner surface of the reservoir 27 with reference to the thick line portion in FIG. 6, or corrosion resistance such as stainless steel may be applied. The inner surface of the reservoir 27 may be coated with a material having a corrosion-resistant material, or a cup made of a material having corrosion resistance may be installed along the inner surface of the reservoir 27. In the example of FIG. 6, corrosion resistance is imparted not only to the storage portion 27 but also to a part of the separation portion 25.

(Fourth modification)
A fourth modification of the above embodiment will be described with reference to FIG. 7. FIG. 7 corresponds to FIG. 2 showing the above embodiment.

In this modification, a part 23a of the casing 23 in which the storage portion 27 is formed is detachably configured with respect to the main body 23b of the casing 23 in which the compression portion 24 is provided.

The detachable configuration can be realized by any known method. For example, it may be realized by screwing, or it may be mechanically detachable without using screws.

According to this modification, the storage unit 27 can be easily replaced. Further, since the storage unit 27 can be made of a material different from that of the compression unit 24, corrosion resistance can be easily imparted to the storage unit 27 as shown in the third modification.

Further, in this modification, the separation portion 25 and the storage portion 27 have a cylindrical shape having a central axis CL. The intake direction of the intake port 21 with respect to the separation portion 25 is not directed to the central axis CL, but is directed to the cylindrical inner surface constituting the separation portion 25.

According to this modification, air flows along the cylindrical inner surface of the separating portion 25. The drain contained in the air adheres to the inner surface by contact with the inner surface, and flows down along the inner surface. Therefore, the drain can be further separated from the air, and the inflow of the drain into the compression portion 24 can be further suppressed.

Although the specific embodiment of the present invention and the modification thereof have been described above, the present invention is not limited to the above-described embodiment and can be variously modified and carried out within the scope of the present invention. For example, an embodiment of the present invention may be obtained by appropriately combining the contents of individual embodiments and modifications. In particular, a part 23a of the casing 23 detachably configured in the fourth modification may have corrosion resistance against drainage at least in the storage portion 27.

1 Compressor 2 Intercooler 3 Aftercooler 4a-4c Flow path piping 10 1st stage compressor body 11 Intake port 12 Discharge port 20 2nd stage compressor body 21 Intake port 22 Discharge port 23 Casing 23a Part of casing 23b Casing Main body 24 Compressor 24a Rotating shaft member 24b Screw rotor 24c Compression wall 24d Introduction port 24e Outlet port 25 Separation part 25a Interfering plate 25b Top plate 25c Opposite plate 26 Cooling part 27 Storage part 27a Perforated plate 28 Discharge port 29 Discharge valve R1 Room R2 Separation room

Claims (11)

The first stage compressor body that compresses gas and
It is provided with a second-stage compressor body that further compresses the gas compressed by the first-stage compressor body.
The second stage compressor body is
Casing with intake and discharge ports,
A compression unit provided in the casing, communicating with the discharge port and compressing the gas,
A compressor provided in the casing, which communicates with the intake port and the compression section and has a separation section having a flow path cross-sectional area of a predetermined size for separating drain from the gas. The compressor according to claim 1, wherein the separation unit is arranged below the compression unit. The compression according to claim 1 or 2, wherein the predetermined size of the flow path cross-sectional area of the separation portion is a size that makes the flow velocity of the gas equal to or lower than the terminal velocity in a cross section perpendicular to the vertical direction. Machine. The separation portion has a cylindrical shape having a central axis and has a central axis.
The invention according to any one of claims 1 to 3, wherein the intake direction of the intake port with respect to the separation portion is not directed to the central axis but is directed to the cylindrical inner surface constituting the separation portion. The compressor described. The compression unit includes a compression wall that defines a compression chamber inside.
The compression wall comprises an inlet for introducing the gas into the compression chamber.
The compressor according to any one of claims 1 to 4, further comprising a non-direct view flow path structure in which the introduction port and the intake port are not in a positional relationship in which they can be directly viewed from each other. The non-direct view flow path structure has an obstacle plate between the introduction port and the intake port that obstructs the flow of the gas linearly from the intake port to the introduction port. 5. The compressor according to 5. The compressor according to any one of claims 1 to 6, wherein a storage portion for storing the drain separated by the separation portion is formed in the casing. The compressor according to claim 7, wherein a perforated plate is provided between the separation portion and the storage portion. The compressor according to claim 7 or 8, wherein the storage unit has corrosion resistance to the drain. The compressor according to claim 7, wherein a part of the casing in which the storage portion is formed is detachably configured with respect to the casing provided with the compression portion. The compressor according to claim 10, wherein a part of the removable casing has corrosion resistance against the drain at least in the storage portion.

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