JP2002227785A - Rotary type air compressor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rotary type air compressor with oil encapsulated capable of accomplishing a compact and low-noise structure to a great extent from any conventional arrangement and of preventing piping, etc., from being damaged and also the compressed air to be discharged from being mixed with the oil. SOLUTION: The rotary type air compressor is composed of a compressor body 1 having a rotor to compress the air with oil contained and equipped with an air suction part, a discharging hole for the compressed air containing oil and a supply hole for the oil, a driving means coupled with the rotor for rotating it, a body casing 22 to accommodate the driving means and having a side wall whereto the compressor body is attached, an oil collecting vessel 3 attached to the side wall in such a way as covering the compressor body and storing the oil in the compressed air fed from the discharging hole, and an oil separating system accommodated in the body casing 22 and separating the oil from the compressed air introduced from the vessel 3, wherein the vessel 3 is provided penetratively with a communication passage leading to the suction hole in the compressor body 1.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an improvement in an air compressor, and more particularly, to an air compressor attached to a vehicle or the like, which compresses air with oil via a rotating body, and further compresses the air. The present invention relates to an oil-filled rotary air compressor that supplies compressed air to a compressed air system in the vehicle by separating oil from air.

[0002]

2. Description of the Related Art A general oil-containing rotary air compressor is designed to provide compressed air by compressing air with oil through a rotating body and separating the oil from the compressed air. In addition, by performing compression with oil instead of air alone, it is possible to remove compression heat, and perform sealing and lubrication using an oil film.

[0003] As a conventional oil-containing rotary air compressor,
FIG. 5 shows a known compressor. FIG.
The air compressor includes a compressor body 1, an electric motor 2 for driving a rotating body housed in the compressor body 1 via a coupling 12, a cooling fan 7 mounted on an output shaft thereof, and a compressor. A suction part connected to the main body 1 and provided with a suction chisel 14 and a suction valve 9 for allowing air flow only in the suction direction, and forming a guide path for air to the compressor main body 1; and also connected to the compressor main body 1. Then, the air compressed in the compressor body 1 is discharged together with the oil mixed in the compressor body 1, and the oil recovery container 3 capable of accumulating the oil therein is connected to the oil recovery container 3. An oil separator 4 having a path for separating the oil from the oil-containing compressed air and returning the separated oil to the oil recovery container, and also connected to the oil recovery container 3, from the oil dust 16 and the compressed air, etc. High temperature due to heat removal An oil supply path for supplying oil to the compressor body including an oil cooler 5 for cooling oil and an oil temperature adjusting valve 6 for switching oil supply to the oil cooler 5 according to oil temperature; The compressed air separated from the oil-filled compressed air is discharged through an after cooler 19 for further post-cooling, allowing air flow only in the discharge direction in the middle of the discharge path, and at a certain pressure or higher. A compressed air discharge portion having a holding pressure check valve 11 which does not allow the flow of the air unless otherwise required is provided. Further, exhaust valves 10 and 13 are usually attached to the oil recovery container 3 and the oil separator 4 in order to discharge compressed air and release pressure.

The air compressor shown in FIG. 5 is generally packaged by accommodating each device in a rectangular box-shaped main body casing.
Is externally provided on the side wall of the main body casing. Also, by attaching the compressor body 1 externally,
Another purpose is to make maintenance easier.

[0005]

However, the above-mentioned oil-injected rotary air compressor external to the compressor body provides an effective means for the purpose of downsizing. In order to be used in an environment where the installation space is limited, such as for a vehicle, there is a demand for further strict miniaturization, and it cannot be said that the purpose has been sufficiently achieved.

Further, since the compressor body 1 is exposed to the outside, noise generated from the rotating body housed inside the compressor body 1 is transmitted to the outside without being shielded, and is particularly used for railway vehicles. In such a case, noise during stand-by at a station platform is regarded as a problem.

The present invention has been made in view of the above circumstances,
It is an object of the present invention to provide a rotary air compressor that achieves further compactness and lower noise than before.

[0008]

According to a first aspect of the present invention, there is provided a rotary air compressor having a rotating body for compressing air with oil, a suction portion for air, and a compression containing oil. A compressor body having an air discharge port and an oil supply port,
A drive unit connected to the rotating body for rotating the rotating body, a main body casing having the side wall on which the driving means is housed and to which the compressor main body is mounted, and a main body casing mounted on the side wall so as to cover the compressor main body. An oil recovery container that accumulates oil in the compressed air from the outlet, and an oil separation system that is housed in the main casing and separates oil contained in the compressed air introduced from the oil recovery container. The oil recovery container is characterized in that a communication passage leading to a suction port of the compressor body is formed in a penetrating state.

According to this configuration, the oil recovery container is mounted on the side wall of the main body casing to which the compressor main body is mounted so as to cover the compressor, so that the compressor main body is included in the oil recovery container. Therefore, as compared with the conventional one, it is equivalent to saving the installation space of the compressor main body, and it is possible to realize a significant downsizing. Further, since the compressor body, which is a noise generating source, is shielded from the outside by the oil recovery container, it is surrounded by a soundproof wall, and the problem of low noise can be solved at once.

A rotary air compressor according to a second aspect of the present invention is the rotary air compressor according to the first aspect, further comprising an oil pipe for returning oil from the oil separation system to the supply port through the oil recovery container. is there.

According to this configuration, since the oil piping path from the oil separation system to the oil supply port provided in the compressor body passes through the inside of the oil recovery container, the piping is not exposed to the outside world by the oil recovery container. It is possible to solve the problem that the pipe is damaged due to collision of foreign matters such as pebbles, which is likely to be generated when the pipe is mounted on a railway vehicle or the like. Also, needless to say, it is not necessary to provide a protector for the pipes and the like, and further downsizing can be achieved in addition to the case of the first aspect.

According to a third aspect of the present invention, in the rotary air compressor according to the first or second aspect, the communication passage is formed by a sleeve fitted into both the suction port and the oil recovery container. Is provided with a suction valve.

According to this structure, the suction valve is structured to be inserted into both the suction port and the oil recovery container, so that a space for disposing the suction valve can be efficiently provided. In addition to the case, further downsizing can be achieved.

According to a fourth aspect of the present invention, there is provided the rotary air compressor according to any one of the first to third aspects, wherein a suction chisel in a direction coaxial with the compressor body is disposed adjacent to the container. Is what it is.

According to this configuration, among the constituent elements, the oil recovery container and the suction chisel, which are elements having a substantially cylindrical outer shape, are adjacent to each other in parallel in a direction coaxial with the compressor body. Therefore, since it can be disposed so as to efficiently occupy the space without making an extra space, claims 1 to 1
In addition to the case of 3, the size can be further reduced.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic cross-sectional view of a rotary air compressor according to the present invention, and is a side view as viewed from a direction perpendicular to a rotation axis of a compressor body. FIG. 2 is a schematic view including a partial cross section of the rotary air compressor according to the present invention, and is a front view as viewed in the direction of the rotation axis of the compressor body. FIG. 3 is a schematic cross-sectional view showing a communication path leading to a suction port of a compressor body formed in an oil recovery container in the rotary air compressor according to the present invention, and a disposing structure of a sleeve and a suction valve inserted therein. It is a figure and the figure seen from the same direction as FIG. FIG. 4 is a system diagram showing the overall configuration of the rotary air compressor according to the present invention. In each of the drawings, components denoted by the same reference numerals are those that exert the same action, and the same names are used in the description.

Referring to FIG. 1, a rotary air compressor according to the present embodiment has a compressor body 1 connected to an air intake valve 9 and an oil-containing compressed air discharge pipe 20, and a rotary air compressor in the compressor body 1. The electric motor 2 for driving the accommodated rotating body (not shown) via a coupling (not shown) and the cooling fan 7 mounted on the output shaft thereof, and the side wall 21 accommodating the electric motor 2 and the compressor main body 1 are attached. An oil recovery container 3 attached to the side wall 21 so as to cover the compressor main body 1; and an oil separator housed in the main body casing 22 and connected to the holding pressure check valve 11 and the exhaust valve 13. 4, oil temperature control valve 6, oil dust 1
An oil circulation system including the oil cooler 6 and the oil cooler 5 and an aftercooler 19 for cooling the compressed air discharged from the pressure holding check valve 11 are provided.

The oil recovery container 3 must satisfy the performance as a pressure container for sealing the oil-containing compressed air discharged from the compressor main body 1 through the pipe 20 together with the side wall 21. It has a structure. As shown in FIG. 2, it is configured in a cylindrical shape so that oil can be efficiently accumulated therein, and further attached so as to be observable from outside so that the amount of accumulated oil can be checked. An oil level gauge 27, an oil supply port 25 for directly supplying oil to the oil recovery container 3 when the amount of accumulated oil is reduced, and a case where accumulated oil is deteriorated and oil needs to be changed. An oil discharge port 26 for discharging old oil, and a compressed air discharge pipe 2
An oil temperature switch 18 for measuring the temperature of the oil-filled compressed air discharged from 0 is provided. Further, the oil adhering plate 2 is located at a position where the oil-filled compressed air discharged from the pipe 20 collides.
4 to provide a structure for promoting oil separation. However,
The shape and position of the oil attachment plate 24 are not necessarily limited to this. And as a constituent material of the oil recovery container 3, it is desirable to use a casting excellent in soundproofing.

The shape of the oil-containing compressed air discharge pipe 20 is as follows.
The accumulated oil is discharged at a position higher than the oil level, and the oil-containing compressed air collides with the lower surface of the oil adhesion plate 24. By forming the pipe 20 in this way, a gap is formed between the oil level of the oil accumulated in the oil recovery container 3 and the discharge-side opening end of the pipe 20, and the discharge of oil-containing compressed air is performed. Since the flow path is formed in a direction away from the oil surface, it is possible to prevent occurrence of firing by oil and air. Thereby, there is an effect that generation of mist-like oil due to firing can be suppressed. When mist-like oil is generated, oil and compressed air cannot be sufficiently separated in the oil separator 4 described later, and as a result, a problem that the discharged compressed air contains an oil component tends to occur. This problem can be solved by the configuration of the pipe 20.
However, the shape of the pipe 20 is not necessarily limited to this as long as the purpose of preventing generation of mist-like oil can be achieved.

The suction valve 9 is provided in a communication passage leading to an air suction port of the compressor body 1 provided in the oil recovery container 3 and in a sleeve 28 fitted as shown in FIG. The sleeve 28 has to have a sealing structure such as a seal 29 because it needs to satisfy the performance as a container for enclosing oil-containing compressed air together with the oil recovery container 3.

The structure of the suction valve 9 will be described in more detail with reference to FIG. The suction valve 9 is
A valve body 30 capable of shielding an air suction port into which is inserted,
A valve rod 31 for supporting the valve element, a piston 32 attached to one end of the valve rod, a cylinder 33 for slidably supporting the piston 32, and a cylinder 3
3 and a spring 34 interposed between the piston 32 and has a structure that allows air to flow only in a suction direction to a suction port provided in the compressor body 1.

At the upstream side of the suction path of the suction air formed by the sleeve 28, a suction chip 14 for removing dust existing in the atmosphere from the suction air is provided as shown in FIG. 1 or FIG. . The suction duster 14 has a cylindrical shape, and its axial direction is the same as the axial direction of the oil recovery container 3 having a substantially cylindrical shape.
And it is arranged so as to be adjacent to the oil recovery container 3.

The oil separator 4 has an oil separation element 15 therein. The oil separator 4 separates oil and compressed air from oil-containing compressed air introduced from the oil recovery container 3 through a pipe 35. Perform separation. The pipe 35 is connected to the oil separator 4 through the side wall 21 as shown in FIG. 1, and a fitting portion between the pipe 35 and the side wall 21 is sealed by a seal (not shown). As shown in FIGS. 1 and 2, an oil supply pipe 36 is provided from the oil separator 4 so as to pass through the side wall 21 and communicate with the air suction port of the compressor body 1. A stop is provided in the vicinity of the connection portion. All of the pipes 36 are provided so as to pass through the inside of the oil recovery container 3. Although not shown, the pipe 36 has a structure in which the pipe 36 is hermetically sealed by a fitting portion with the side wall 21 similarly to the pipe 35.

Another system other than the pipe 36 is also connected to the oil separator 4 as a system for returning separated oil to the compressor body 1. FIG. 1 illustrates this system. The oil separator 4 has an oil pipe (not shown) connected on the side opposite to the side in contact with the side wall 21, and this pipe is connected to the oil temperature adjusting valve 6. The oil temperature control valve 6 is connected to the oil stencil 16 and then connected to the compressor body 1 by a pipe 37.
And an oil cooler 5 that cools the oil, and a pipe 38 that forms a path for circulating the oil. The oil dust 16 is housed in the main casing 22, and a pipe 37 connected to the oil dust 16 and reaching the compressor body 1 has a structure passing through the side wall 21. For this reason, although not shown, the fitting portion between the pipe 37 and the side wall 21 has a structure sealed by a seal. A pipe 37 that has been guided into the oil recovery container 3 through the side wall 21 is connected to the compressor main body 1 so as to bypass a lower portion thereof, as shown in FIG. As shown in FIG. 1, the pipe 38 is disposed so as to form an oil circulation path between the oil temperature adjustment valve 6 and the oil cooler 5 installed on the upper part of the main body casing 22. In the above-described configuration, the oil temperature adjusting valve 6 controls one of a path for guiding oil to the pipe 37 and a path for circulating oil between the oil cooler 5 through the pipe 38 in accordance with the temperature of the compressed air containing oil. It consists of a valve that can be switched so that it can be selected. In addition, the installation position of the oil cooler 5 is not necessarily limited to the upper part of the main body casing 22, and may be a lower part, a side part, or an inner part of the main body casing 22. It will be arranged to connect at the bottom, side or inside. Further, the oil separation system described in the claims is configured to include the oil separator 4 having the oil separation element 15 therein and the oil filter 16, and in the present embodiment, The oil is supplied to the compressor main body 1 through the pipe 36 and the pipe 37, and further connected to an oil cooling path including the oil cooler 5 via an oil temperature adjusting valve 6.

The oil separator 4 is further connected to a path for discharging compressed air from which oil has been separated. At the upper part of the oil separator 4, a holding pressure check valve 11 for discharging compressed air from which oil has been separated is installed. They are connected so that air flows in. Although not shown, the holding pressure check valve 11 includes a valve body and a spring, and allows air flow only in the discharge direction so that the inflow of compressed air does not flow backward, and is provided. The air flow is not allowed unless the pressure exceeds a certain level. The holding pressure check valve 11 is connected to a pipe 39 for guiding compressed air to an aftercooler 19 installed at an upper part of the main body casing 22, and the compressed air is sent to the outside through the aftercooler 19. . In addition, the installation position of the aftercooler 19 is not necessarily limited to the upper part of the main body casing 22 like the oil cooler 5, and may be a lower part, a side part, or the inside. In addition, the aftercooler 19 and the oil cooler 5 do not necessarily have to be adjacent to each other. For example, the aftercooler 19 may be configured to be above the main body casing 22 and the oil cooler 5 may be configured to be inside.

The oil separator 4 has a structure in which the oil separator 4 and the interior of the oil recovery container 3 connected to the oil separator 4 can be depressurized. Is provided with an exhaust valve 13. The exhaust valve 13 is preferably, for example, an electromagnetic valve so that the valve can be opened and closed in conjunction with the compressor operation. In addition, it is desirable that a safety valve 10 be provided separately from the exhaust valve 13 so that pressure can be released at the time of abnormality or the like.

The rotary air compressor according to the present embodiment is configured as described above.
For example, in order to be attached to a lower part of a railway vehicle, the vehicle has a hanger 40 shown in FIGS. 1 and 2. The hanging hand 40 has a flat plate shape, and is bent so that one end of the flat plate projects partly vertically,
Is formed. The main casing is arranged such that the overhanging portion projects in a direction opposite to the rotary air compressor and is positioned above the after-cooler 5 to the oil cooler 19 disposed above the rotary air compressor. 2
2 on both sides. A hole is formed in the overhanging portion of the hanging hand 40 so that a bolt can pass therethrough.
Attached with 1. With this configuration, the rotary air compressor can be easily attached to a lower portion of the vehicle or the like, and vibration of the vehicle is less likely to be transmitted to the rotary air compressor.

Next, the operation of the rotary air compressor according to this embodiment will be described with reference to FIG. First, a description will be given along the flow of air.

The air in the atmosphere, which is the raw material of the compressed air, is sucked into the suction chillers 14 whose interior has a negative pressure. The suction dust filter 14 is composed of several layers of filters, and the filters remove small foreign matters such as dust and moisture present in the air.

The clean air from which the foreign matter has been removed is further guided toward the suction valve 9. In the suction valve 9, the valve body 30 is positioned so as to shield the air suction port of the compressor main body 1 by the spring 34. Therefore, the valve body 30 is pushed down by the suction air,
An inflow path of air leading into the compressor body 1 is formed. Therefore, when no negative pressure is generated on the side of the compressor body 1 of the valve body 30, no air flows in and no movement of air occurs, and only the flow of air to the side of the compression body 1 is restricted. Will be tolerated.

The compressor body 1 has a rotating body having an impeller portion for giving kinetic energy to air and compressing the rotating body. The rotating body is connected to the electric motor 2 via a coupling 12. It is connected. This electric motor 2
As a result, a driving force for rotation is given to the rotating body in the compressor body 1. The main body casing 2 of the electric motor 2 and the like is cooled by a cooling fan 7 attached to the electric motor 2.
Heat is removed from the temperature raising equipment disposed in the inside 2.

The rotary body shown in FIG. 4 is a screw-type air compressor having two shafts, one of which is driven and the other of which is provided with a rotational force by fitting.

Oil is supplied to the compressor body 1 from two places and mixed with compressed air. The supply of one oil is from the air suction port, and the supply of the other oil is performed directly to the compressor body 1. By this operation, the oil mixed with the compressed air removes the compression heat generated from the air in the compression process, a sealing effect that increases the airtightness by forming an oil film in the compressor body 1, and This has the effect of removing the heat generated at the contact surfaces between the screws.

The oil-containing compressed air compressed in the compressor body 1 and mixed with the oil is discharged into the oil recovery container 3 through the discharge pipe 20. At the outlet of the pipe 20, the oil-containing compressed air collides with the oil-attached plate 24, and a part of the oil contained in the oil-containing compressed air is separated from the compressed air and accumulated inside the oil recovery container 3. . At this time, the oil-containing compressed air is discharged so as to pass through the oil temperature switch 18, and the temperature of the oil-containing compressed air can be detected by the oil temperature switch.

The oil-containing compressed air discharged to the compressor body 1 passes through the pipe 35 and is introduced into the oil separator 4. In the oil separator 4, the oil separation element 15
For example, oil and compressed air are separated.

The compressed air from which the oil has been separated is supplied to the holding pressure check valve 1
Guided to 1. In the pressure holding check valve 11, a valve body is provided via a spring so as to shield a discharge port of the compressed air from the oil separator 4. However, the compressed air was discharged from the oil separator 4. In this case, the shieldable valve body is pressed, whereby the compressed air is discharged from the oil separator 4 through the discharge port. Since this valve element is pressed against the discharge port by a spring, a discharge path for compressed air is not formed unless a surface pressure of a certain value or more is applied to the valve element that shields the discharge port. Therefore, the pressure of the compressed air discharged from the oil separator 4 is maintained at a certain value or more.

The compressed air discharged through the pressure holding check valve 11 is guided by a pipe 39 and then reaches an aftercooler 19. Here, the heat of the compressed air is further removed to provide the compressed air to the outside. It is desirable to provide a dehumidifier on the downstream side of the after cooler 19 to dry the compressed air.

Next, an oil circulation system used for cooling compressed air and the like will be described. Since the oil mixed with the compressed air has been described in accordance with the flow of the air, the process from separation by the oil separator 4 to supply to the compressor body 1 will be described.

The oil separated by the oil separator 4 is
Collect at the bottom of the. Since the oil is in a high-pressure atmosphere by compressed air, the oil is guided through the pipe 36 toward the air suction port on the low pressure side, and the oil is supplied from the air suction port to the compressor body 1. Become.

The oil is also guided from the piping connected to the bottom of the oil separator 4 to the oil temperature adjusting valve 6 which is also on the low pressure side.
In the oil temperature adjusting valve 6, according to the oil temperature, the pipe 38 and the pipe 3
7 is selected. If the oil temperature is higher than a predetermined value, the pipe 38 is selected for cooling the oil by the oil cooler 5, and if the oil temperature is lower than the predetermined value, the pipe 37 is selected. The oil guided to the pipe 37 removes foreign substances in the oil by the oil dust 16,
After being cleaned, it is supplied to the compressor body 1.

The rotary air compressor according to the present embodiment operates as described above to provide compressed air to the outside. By attaching to a railcar, it can be used as a compressed air supply source to a device that is loaded on a railcar and operates with compressed air.

The embodiment described above has the following effects. (1) The conventional rotary air compressor enables a significant reduction in size that could not be realized at all. Accordingly, when a compressed air supply source must be installed in a limited space such as a vehicle, the compressed air supply source becomes a very effective compressed air supply source. In particular, a typical example is a use for a railway vehicle. In the case of railway vehicles, the distance between the running rails is fixed, so the width of the vehicle is restricted, and the location of the compressed air supply source is also limited due to reasons such as securing the room for the cabin, It must be installed in a very limited space such as the lower part of the vehicle. Therefore, the rotary rotary air compressor according to the present embodiment provides effective means.

(2) In the conventional rotary air compressor, since the compressor body, which is a noise source, has to be exposed to the outside, especially when used for railway vehicles, The level of the noise was regarded as a problem. However, since the noise source is completely covered by the container having the soundproofing function, the noise can be significantly reduced.

(3) Further, when used in a railway car, the installation place is limited to the lower part of the car as described above. However, the conventional rotary air compressor has a structure in which piping is exposed to the outside. There was a fatal disadvantage that foreign materials such as gravel and pebbles scattered on the railway surface collided with the exposed piping and were liable to be damaged. The only way to prevent this is to use a means such as providing a protector so as to cover the pipes exposed to the outside.Since this will complicate the structure and increase the number of components, measures must be taken in practice. It was difficult. However, according to the present embodiment, since there are no pipes exposed to the outside, the collision itself with the pipes such as pebbles does not occur, and the above problem can be solved fundamentally.

(4) In the conventional rotary air compressor, in order to reduce the size of the apparatus, it is necessary to reduce the volume of the container for accumulating oil.
Since firing of oil and air is likely to occur, there has been a problem in that oil is mixed into compressed air. However, in the rotary air compressor according to the present embodiment, the device can be significantly reduced in size by means not depending on the size of the oil storage container.
The problem of firing can be solved, and the amount of oil mixed into the compressed air can be significantly reduced. Further, in the present embodiment, the structure of the pipe for discharging the compressed air containing oil to the oil recovery container is improved, so that an effect of further reducing the amount of mixed oil can be obtained.

The embodiment is not limited to the above, and may be modified as follows, for example. (1) If the installation structure of the suction dust box can achieve the purpose of achieving compactness by occupying space efficiently, it is not necessarily in the direction of being coaxial with the compressor body but in the direction perpendicular to the axis. May be. As a result, without removing the rotary air compressor from the vehicle body,
A structure may be adopted in which the suction duster alone can be attached to and detached from the compressor.

(2) The suction valve does not necessarily have to be inserted into the oil recovery container as long as the object of compactness can be achieved, and an air suction path is formed between the suction dust and the oil recovery container. It may be provided.

(3) If it is not used for a railway car, the significance of preventing collision of foreign matter or the like with pipes is lost. Therefore, in this case, the oil pipe for supplying oil from the oil separation system to the compressor main body does not necessarily have to pass through the oil recovery container as long as the object of compactness is achieved.

(4) The connecting portion for transmitting the driving force from the electric motor to the rotating body accommodated in the compressor main body is not necessarily a coupling, but may be, for example, transmitted via a pulley and a belt. You may.

(5) The rotating body accommodated in the compressor body is not limited to the screw type, but may be, for example, a two-leaf type, a vane type, a scroll type, or a rolling piston type.

[0051]

According to the first aspect of the present invention, since the oil recovery container is mounted on the side wall of the main body casing to which the compressor main body is mounted so as to cover the compressor, the compressor main body is included in the oil recovery container. Therefore, compared to the conventional one, it is equivalent to saving the installation space of the compressor main body, and it is possible to realize a significant downsizing. Further, since the compressor body, which is a noise generating source, is shielded from the outside by the oil recovery container, it is surrounded by a soundproof wall, and the problem of low noise can be solved at once.

According to the second aspect of the present invention, since the oil piping path from the oil separation system to the oil supply port provided in the compressor body passes through the inside of the oil recovery container, the oil piping is not exposed to the outside world. When used for railroad vehicles and the like, which is protected by a collection container, problems such as damage to piping due to collision of foreign matters such as pebbles can be solved. In addition, needless to say, it is not necessary to provide a protector for the pipes and the like, so that an effect is obtained that the size can be further reduced in addition to the case of the first aspect.

According to the third aspect of the present invention, since the suction valve is structured to be inserted into both the suction port and the oil recovery container, a space for disposing the suction valve can be efficiently provided. Alternatively, in addition to the case of 2, there is an effect that the size can be further reduced.

According to the fourth aspect of the present invention, among the constituent elements, the oil recovery container and the suction chisel, which are elements having substantially cylindrical outer shapes, are adjacent to each other in parallel in a direction coaxial with the compressor body. By doing so, it is possible to efficiently arrange the space without occupying an extra space, so that there is an effect that it is possible to further reduce the size in addition to the case of the first to third aspects.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view of a rotary air compressor according to the present invention, which is a side view seen from a direction perpendicular to a rotation axis of a compressor main body.

FIG. 2 is a schematic view including a partial cross section of the rotary air compressor according to the present invention, and is a front view as viewed in a direction of a rotation axis of a compressor body.

FIG. 3 is a schematic cross-sectional view showing a communication path to a suction port of a compressor main body formed in an oil recovery container in the rotary air compressor according to the present invention, and an arrangement structure of a sleeve and a suction valve inserted into the communication path. It is a figure and the figure seen from the same direction as FIG.

FIG. 4 is a system diagram showing the overall configuration of the rotary air compressor according to the present invention.

FIG. 5 is a schematic diagram showing an entire configuration of a rotary air compressor according to a conventional technique.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Compressor main body 2 Electric motor 3 Oil recovery container 4 Oil separator 9 Suction valve 14 Suction chill 15 Oil separation element 16 Oil chill 20 Pipe 21 Side wall 22 Body casing 28 Sleeve 35-39 Pipe

Claims (4)

[Claims] 1. A compressor body having a rotary body for compressing air with oil, having a suction part for air, a discharge port for compressed air containing oil, and a supply port for oil, and connected to the rotary body. A driving means for rotating the rotating body, a main body casing having the side wall on which the driving means is housed and on which the compressor main body is mounted, and a discharge port mounted on the side wall so as to cover the compressor main body. An oil recovery container that accumulates oil in compressed air from the tank, and an oil separation system that is housed in the main casing and separates oil contained in compressed air introduced from the oil recovery container. A rotary air compressor in which a communication passage leading to a suction port of the compressor body is formed in a container so as to penetrate therethrough. 2. A rotary air compressor having an oil pipe for returning oil from the oil separation system to the supply port through the oil recovery container. 3. The rotation according to claim 1, wherein the communication passage is formed by a sleeve fitted into both the suction port and the oil recovery container, and a suction valve is provided in the sleeve. Type air compressor. 4. The rotary air compressor according to claim 1, wherein a suction chisel in a direction coaxial with said compressor main body is disposed adjacent to said container.