KR100445887B1 - Rotary air compressor - Google Patents

Abstract

(assignment)

The present invention provides a rotary air compressor containing oil, which can realize greater compactness and lower noise than in the past, and can also solve problems such as damage to pipes and mixing of oil into compressed air discharged at a glance. .

(Solution)

Compressor body (1) having a rotating body for compressing air with oil and having an air inlet, an outlet of compressed air including oil, and an oil supply port, and connected to the rotating body, A driving means for rotating the rotating body, a main casing 22 having a side wall to which the driving means is accommodated and to which the compressor main body is attached, and a side casing attached to the compressor to cover the compressor main body, and compressed from the discharge port. An oil recovery vessel (3) for accumulating oil in air, and an oil separation system for separating oil contained in the compressed air contained in the main body casing and introduced from the oil recovery vessel (3); (3) characterized in that the communication path leading to the suction port of the compressor main body (1) is formed in a through state.

Description

Rotary Air Compressor {ROTARY AIR COMPRESSOR}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to an improvement of an air compressor, and more particularly, to a vehicle or the like, which compresses air with oil through a rotating body and separates oil from compressed air. A rotary air compressor containing oil which provides compressed air to a compressed air cylinder therein.

A rotary air compressor containing a general oil is an apparatus for providing compressed air by compressing oil accompanying oil through a rotating body and separating oil from the compressed air, and is not an air unit. By compressing with oil, it has the characteristics of being able to remove heat of compression, sealing with oil film, and lubrication.

As a rotary air compressor in which a conventional oil is contained, the compressor which shows the structure in FIG. 5 is well-known. The air compressor of FIG. 5 includes a compressor main body 1, an electric motor 2 for driving a rotating body accommodated in the compressor main body 1 through a coupling 12, and a cooling fan 7 attached to the output shaft thereof. A suction part connected to the compressor main body 1 and having a suction dust filter 14 and a suction valve 9 allowing air flow only in the suction direction to constitute an air induction path to the compressor main body 1; Similarly, the oil recovery container 3 connected to the compressor main body 1, and the air compressed in the compressor main body 1 is discharged together with the oil mixed in the compressor main body 1, and can accumulate oil therein. ) And the oil recovery container (3) connected to the oil recovery container (3) and having a path for separating oil from the inlet compressed air and returning the separated oil to the oil recovery container. 3) to generate heat from the oil dust filter 16 and compressed air. Oil cooler (5) for cooling the oil that has become hot and oil temperature adjusting valve (6) for switching the oil passage to the oil cooler (5) by the oil temperature and supplying oil to the compressor main body. And through the aftercooler 19 for further post-cooling the compressed air separated from the inlet compressed air into the oil separator 4, allowing the flow of air only in the discharge direction in the middle of the outlet, If the pressure is not higher than a predetermined pressure, the discharge portion of the compressed air having a pressure check valve 11 which does not allow air flow is arranged. In addition, in the oil recovery container 3 and the oil separator 4, it is common to provide exhaust valves 10 and 13 in order to discharge the compressed air so that the pressure can be released.

The air compressor shown in Fig. 5 is generally packaged by accommodating each device in a rectangular box-shaped main body casing. For the purpose of miniaturization, the compressor main body 1 is provided on the side wall of the main body casing outside. It is known. In addition, the compressor main body 1 is provided on the outer side, which also aims to facilitate maintenance.

However, the above-mentioned rotary air compressor containing the compressor main body type oil is provided with an effective means for the purpose of miniaturization. However, in order to be used in an environment where the installation space is limited, such as for a railroad car, it is more and more compact. There is demand, and it is in a state that it cannot say that the aim is fully achieved.

In addition, since the compressor main body 1 is exposed to the outside, the noise generated from the rotating body housed inside the compressor main body 1 is transmitted to the outside as it is without being shielded, especially when used for railway vehicles, Noise, etc., when waiting on the reverse platform is a problem.

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

1 is a schematic cross-sectional view of a rotary air compressor according to the present invention, and is a side view viewed in a direction perpendicular to the rotation axis of the compressor main body.

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 seen in the direction of the rotation shaft of the compressor main body.

Figure 3 is a schematic cross-sectional view showing a communication path leading to the inlet port of the compressor main body formed in the oil return container in the rotary air compressor according to the present invention and the arrangement arrangement of the sleeve and the suction valve fitted therein, the same direction as in Figure 2 This is the view from.

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

5 is a schematic diagram showing the overall configuration of a rotary air compressor in the prior art.

(Explanation of the sign)

1 Compressor Body 2 Electric Motor

3 Oil recovery container 4 Oil separator

9 Suction valve 14 Suction dust filter

15 Oil separation element 16 Oil dust filter

20 Tubing 21 Sidewalls

22 Body casing 28 sleeve

35 ~ 39 Piping

The rotary air compressor according to claim 1, which solves the above problems, has a rotating body for compressing air with oil, and has a suction part of air, an outlet of compressed air including oil, and a supply port of oil. A main body, a driving means connected to the rotating body and rotating the rotating body, a main body casing having the side wall in which the driving means is accommodated and the compressor main body is installed, and installed so as to cover the compressor main body on the side wall. And an oil recovery system for accumulating oil in the compressed air from the discharge port, and an oil separation system for separating oil contained in the compressed air contained in the main body casing and introduced from the oil recovery container. The container is characterized in that the communication path leading to the suction port of the compressor main body is formed in a through state.

According to this configuration, since the oil recovery container is attached to the side wall of the main body casing in which the compressor body is installed, the compressor body is embedded in the oil recovery container. This is equivalent to saving the cost, and can significantly reduce the size. In addition, since the noise-compressing main body, which is the source of noise generation, is shielded from the outside by an oil recovery container, it is surrounded by a soundproof wall, and the problem of low noise can be solved at once.

The rotary air compressor according to claim 2, wherein the oil piping for returning oil from the oil separation system to the supply port via the oil recovery container is provided.

According to this configuration, since the oil piping path from the oil separation system to the supply port of the oil installed in the compressor body passes through the oil recovery container, the pipe is protected by the oil recovery container without exposing the outside to the railroad vehicle. It is possible to solve the problem of damage to the pipe due to foreign matter collision, such as small stones, which are easily generated when installed on the back. As a matter of course, it is not necessary to provide a protector or the like for pipes, and in addition to the case of claim 1, further compactness can be achieved.

The rotary air compressor according to claim 3, wherein the communication path is formed by a sleeve fitted to both the suction port and the oil recovery container, and a suction valve is provided in the sleeve. .

According to this configuration, since the suction valve is fitted into both the suction port and the oil recovery container, the space for installing the suction valve arrangement can be efficiently installed, and in addition to the case of claim 1 or 2, further compactness can be achieved. We can plan.

The rotary air compressor according to claim 4, wherein the suction dust filter in a direction coaxial with the compressor main body is provided adjacent to the oil recovery container according to claim 1 or 2.

According to this structure, since the oil collection container and the suction dust filter, which are elements having a substantially cylindrical shape, are adjacent in parallel to the direction coaxial with the compressor main body, it does not create an extra space and is efficient. Since it can arrange so that it may take up space, in addition to the case of Claim 1 or 2, further compactness can be attained.

(Example)

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described based on drawing. 1 is a cross-sectional schematic view of a rotary air compressor according to the present invention, and is a side view seen in a direction perpendicular to the rotation axis of the compressor main body. 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 seen in the direction of the rotation axis of the compressor main body. 3 is a schematic cross-sectional view showing a communication path leading to a suction port of a compressor main body formed in an oil return container and an arrangement structure of a sleeve and a suction valve fitted therein in the rotary air compressor according to the present invention. It is the figure seen from the direction. 4 is a system flow diagram showing the overall configuration of a rotary air compressor according to the present invention. In addition, in each figure, the component which attaches | subjects the same number is an element which exhibits the same effect | action, and shall use the same name in description.

In FIG. 1, the rotary air compressor according to the present embodiment includes a compressor main body 1 connected to an intake valve 9 of air and a discharge pipe 20 of inlet compressed air, and a compressor main body 1 housed in the compressor main body 1. An electric motor 2 for driving a rotating body (not shown) through a coupling not shown together, a cooling fan 7 provided on the output shaft thereof, and a side wall on which the motor 2 is accommodated and the compressor main body 1 is installed ( The main body casing 22 having the body 21, the oil recovery container 3 provided to cover the compressor body 1 on the side wall 21, the main body casing 22, are housed in the pressure check valve 11 and An oil separator (4) connected to the exhaust valve (13), an oil circulation system including an oil temperature regulating valve (6), an oil dust filter (16) and an oil cooler (5), and a pressure check valve (11) discharged from the It has an aftercooler 19 which cools compressed air.

The oil recovery container 3, together with the side wall 21, must meet the performance as a pressure vessel for sealing compressed air containing oil discharged from the compressor body 1 through the pipe 20 from the compressor body 1, so that the sealing ( 23) It has a sealing structure. As shown in FIG. 2, an oil level gauge configured to have a cylindrical shape in order to efficiently accumulate oil therein, and attached to the externally observable so as to confirm the amount of accumulated oil ( 27) or oil supply port 25 so that the oil can be supplied directly to the oil recovery container 3 when the amount of accumulated oil is low, or when the accumulated oil is deteriorated and needs to be refueled. An oil outlet 26 for discharging is provided, and an oil temperature switch 18 for measuring the temperature of compressed air containing oil discharged from the compressed air discharge pipe 20. Moreover, the oil attachment plate 24 is provided in the position where the compressed air containing the oil discharged | emitted from the piping 20 collides, and it has a structure which promotes oil separation. However, the shape and position of the oil attachment plate 24 are not necessarily limited to this. As the constituent material of the oil recovery container 3, it is preferable to use a casting excellent in sound insulation.

The shape of the discharge pipe 20 of the compressed air containing the oil is discharged at a higher position from the oil surface of the accumulated oil, and also impinges the compressed air containing the oil on the lower surface of the oil attachment plate 24. It is formed to be. As the pipe 20 is formed in this way, a gap is formed between the oil surface of the oil accumulated in the oil recovery container 3 and the open end of the discharge side of the pipe 20, and the discharge flow path of the inflow compressed air is Since it is formed in the direction away from an oil surface, foaming by oil and air can be prevented. Thereby, there exists an effect which can suppress generation | occurrence | production of the fog oil by foaming. When mist-like oil is generated, it is not easy to separate oil and compressed air in the oil separator 4 which will be described later, and as a result, the problem of easily containing oil in the discharged compressed air is likely 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 oil is achieved.

The intake valve 9 is installed in a communication path leading to the air intake port of the compressor main body 1 installed in the oil recovery container 3 and in the sleeve 28 fitted as shown in FIG. The sleeve 28 has a sealing structure such as a seal 29 because the sleeve 28 needs to satisfy the performance as a container for encapsulating compressed air containing oil together with the oil recovery container 3.

The structure of the intake valve 9 is demonstrated in more detail using FIG. The intake valve 9 includes a valve body 30 for freely shielding an air inlet in which a sleeve 28 is fitted, a valve rod 31 for supporting the valve body, and a piston 32 provided at one end of the valve rod. ), A cylinder cylinder 33 for slidably supporting the piston 32, and a spring 34 fitted between one end in the cylinder cylinder 33 and the piston 32, and the compressor main body ( Take the structure to enable the flow of air only in the suction direction to the suction port installed in 1).

On the suction upstream side of the induction path of the suction air constituted by the sleeve 28, a suction dust filter 14 for removing dust existing in the atmosphere from the suction air is provided as shown in Figs. The suction dust filter 14 has a cylindrical shape, and its axial direction is provided in the same direction as the axial direction of the oil recovery container 3 which has a substantially cylindrical shape, and is provided adjacent to the oil recovery container 3. It is.

The oil separator 4 has an oil separation element 15 therein, and the oil separator 4 compresses oil and oil from the inlet compressed air introduced from the oil recovery container 3 through the pipe 35. Separate the air. As shown in FIG. 1, the pipe 35 is connected to the oil separator 4 through the side wall 21, and the fitting portion of the pipe 35 and the side wall 21 is not shown in the seal. Take a structure that is sealed by. 1 and 2, an oil supply pipe 36 is provided from the oil separator 4 to the air inlet of the compressor main body 1 through the side wall 21. The throttle is provided in the vicinity of the connection part of (4) and the piping 36. All of these pipes 36 are provided so as to pass through the inside of the oil recovery container 3. Although not shown, the piping 36 has a structure sealed at the fitting portion with the side wall 21 like the piping 35.

The oil separator 4 is also connected with another system other than the pipe 36 as a system for returning the separated oil to the compressor main body 1. In FIG. 1, this system will be described. The oil separator 4 has an oil pipe (not shown) which is connected to the side surface on the side opposite to the side surface in contact with the side wall 21, and this pipe is connected to the oil temperature regulating valve 6. The oil temperature regulating valve 6 is a path for circulating oil between the pipe 37 connected to the compressor main body 1 after connecting to the oil dust filter 16 and the oil cooler 5 for cooling the oil. It is connected to the pipe 38 to form a. The oil dust filter 16 is housed in the main body casing 22, and the pipe 37 connected to the oil dust filter 16 and reaching the compressor main body 1 has a structure passing through the side wall 21. . For this reason, although the fitting part of the piping 37 and the side wall 21 is not shown in figure, it takes the structure sealed by a seal. The pipe 37 passing through the side wall 21 and guided into the oil recovery container 3 is connected to the compressor main body 1 so as to bypass the lower part thereof as shown in FIG. As for the pipe 38, as shown in FIG. 1, it is provided so that the oil circulation path may be comprised between the oil temperature regulating valve 6 and the oil cooler 5 provided in the upper part of the main body casing 22. As shown in FIG. . In the above configuration, the oil temperature regulating valve 6 circulates the oil between the path leading oil to the pipe 37 and the oil cooler through the pipe 38 in accordance with the temperature of the inlet compressed air. It consists of a valve that can be switched to select either of In addition, the installation position of the oil cooler 5 is not necessarily limited to the upper part of the main body casing 22, The lower part, the side part, or the inside of the main body casing 22 may be sufficient, In that case, the piping 38 and the main body casing ( 22) to be installed so as to be connected from the lower part, the side part or the inside. The oil separation system described in the claims is composed of an oil separator 4 having an oil separation element 15 therein and an oil dust filter 16. In this embodiment, the piping The oil is supplied to the compressor main body 1 through the 36 and the pipe 37, and is connected to the oil cooling path including the oil cooler 5 through the oil temperature regulating valve 6.

The oil separator 4 is also connected with a path for discharging compressed air from which oil is separated. At the upper part of the oil separator 4, a pressure check valve 11 for discharging the compressed air from which oil is separated is provided. The pressure check valve 11 is not shown, but the compressed air is discharged from the oil separator 4. Is connected to inflow. Although not shown in the figure, the pressure check valve 11 has a valve body and a spring, and allows the flow of air only in the discharge direction so that the compressed air that flows in does not flow back, and also has a certain pressure. If it is not abnormal, it has a structure that does not allow air flow. And the pressure checking valve 11 is connected with the piping 39 which guides compressed air to the aftercooler 19 provided in the upper part of the main body casing 22, and the compressed air is connected through the aftercooler 19. As shown in FIG. Is sent out. 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 an inside. In addition, the aftercooler 19 and the oil cooler 5 do not necessarily need to be adjacent, for example, the aftercooler 19 is the upper part of the main body casing 22, and the oil cooler 5 is the structure inside it. May be taken.

The oil separator 4 is then evacuated to the atmosphere directly from the oil separator 4 in order to enable the pressure reduction of the oil separator 4 and the oil recovery container 3 conductive to the oil separator 4. The exhaust valve 13 is provided so that it may be. It is preferable that this exhaust valve 13 is a solenoid valve so that valve opening and closing may be performed, for example in conjunction with a compressor operation | movement operation. Moreover, unlike the exhaust valve 13, it is preferable that the safety valve 10 is provided so that pressure may be released in case of abnormality.

The rotary air compressor which concerns on this embodiment is comprised as mentioned above, and has the hanging part 40 shown in FIG. 1 and FIG. 2 so that this rotary air compressor may be installed in the lower part of a railway vehicle, for example. . The hanging part 40 has a flat plate shape, and is bent and processed so that one end of the flat plate may partially protrude vertically. Then, the elongated portion protrudes in the opposite direction to the rotary air compressor, and is located on the upper side of the aftercooler 5 to the oil cooler 19 provided above the rotary air compressor, so that both sides of the main body casing 22 are located. Installed in In the protruding portion of the hanging portion 40, a boring process for penetrating the bolt is provided, and the vehicle body mounting bolt 42 is provided with the anti-vibration pad 41 in this hole. This configuration facilitates installation of a rotary air compressor to the underside of the vehicle, and also makes it difficult to transmit vibrations of the vehicle to this rotary air compressor.

Next, with reference to FIG. 4, the operation form of the rotary air compressor which concerns on a present Example is demonstrated. First, the description will be given along the flow of air.

Air in the atmosphere, which is the raw material of the compressed air, is sucked into the suction dust filter 14 whose inside is negative pressure. The suction dust filter 14 is composed of several layers of filters, and the foreign matters, moisture, and the like, such as various dusts and the like existing in the air, are removed from the filter.

Clean air from which foreign matter has been removed is also directed to the intake valve 9. In the intake valve 9, the valve body 30 is positioned by the spring 34 so as to shield the air intake port of the compressor main body 1. Because of the negative pressure, the valve body 30 is pushed down by the intake air, and an inflow path of air passing into the compressor main body 1 is formed. Therefore, when no negative pressure is generated on the compressor main body 1 side of the valve body 30, air is not introduced and no movement of air occurs, and only the flow of air to the compressor main body 1 side is achieved. Will be allowed.

The compressor main body (1) has a rotating body having an impeller portion for imparting and compressing kinetic energy to air therein, which is connected to the electric motor (2) via a coupling (12). have. By this electric motor 2, the driving force for rotating to the rotating body in the compressor main body 1 is provided. In addition, the temperature increase device provided in the main body casing 22, such as the electric motor 2, is heat-released by the cooling fan 7 provided in the electric motor 2. As shown in FIG.

4 is a screw air compressor having two shafts, one of which is on the driving side and the other of which rotates by fitting.

The compressor main body 1 is supplied with oil at two parts and mixed with the compressed air. One oil is supplied from the air intake port, and the other oil is supplied directly to the compressor body 1. By this operation, the oil mixed with the compressed air has the effect of removing the heat of compression generated from the air in the compression process, the sealing effect of enhancing the airtightness by forming the oil film in the compressor main body 1, and It has the effect of removing the heat generated from the contact surface between the screws of each shaft.

Incoming compressed air compressed in the compressor body 1 and mixed with oil is discharged into the oil recovery container 3 through the discharge pipe 20. At the outlet of the pipe 20, compressed air containing oil collides with the oil attachment plate 24, and a part of the oil contained in the inlet compressed air is separated from the compressed air, and the inside of the oil recovery container 3 Accumulates in. At this time, the compressed air containing oil is discharged to pass through the oil temperature switch 18, and the oil temperature switch can detect the temperature of the inlet compressed air.

Compressed air containing the oil discharged to the compressor main body (1) passes through the pipe (35) and is introduced into the oil separator (4). In the oil separator 4, the oil and the compressed air are separated by the oil separating element 15 and the like therein.

Compressed air from which oil is separated is led to the pressure check valve (11). In the pressure checking valve 11, a valve body is provided through a spring so as to shield the outlet of the compressed air from the oil separator 4, and if there is discharge of the compressed air from the oil separator 4, the shielding is provided. Possible valve bodies are pressurized, whereby compressed air is discharged from the oil separator 4 through the outlet port. Since the valve body is pressed against the outlet port by a spring, the valve body that shields the outlet port is not formed in the outlet of the compressed air unless a surface pressure of a certain value or more is added. Therefore, the pressure of the compressed air discharged | emitted from the oil separator 4 is maintained above some fixed value.

The compressed air discharged through the pressure check valve 11 is led to the aftercooler 19 after being guided by the pipe 39. Here, the compressed air is further dehumidified and the compressed air is supplied to the outside. It is preferable to provide a dehumidifier on the wake side of the aftercooler 19 and to dry compressed air.

Next, a description will be given of the oil circulation system used for cooling the compressed air or the like. Since the oil mixed with the compressed air has been described according to the flow of air, it will be described until it is separated from the oil separator 4 and supplied to the compressor main body 1.

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

Similarly, oil is also introduced from the pipe through the bottom of the oil separator 4 to the oil temperature regulating valve 6 on the low pressure side. In the oil temperature regulating valve 6, the oil circulation system of either the pipe 38 or the pipe 37 is selected in accordance with the oil temperature. If the oil temperature is higher than a predetermined value, the pipe 38 is selected to cool the oil in 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 is supplied to the compressor body 1 after the foreign matter in the oil is removed from the oil dust filter 16 and cleaned.

The rotary air compressor according to the present embodiment operates as described above, and provides compressed air to the outside. The rotary air compressor is installed in, for example, a lower portion of a railway vehicle using the above-described hanging portion 40. It can be used as a supply source of compressed air to equipment loaded on a railroad car and operating in compressed air.

The embodiment described above has the following effects.

(1) In the conventional rotary air compressor, it is possible to greatly reduce the size of the conventional rotary air compressor. As a result, when a source of compressed air must be provided in a limited space such as a vehicle, it becomes a highly effective source of compressed air. In particular, the typical use as a railway vehicle is mentioned. In the case of railroad cars, the vehicle width is limited because the distance between the running rails is determined, and the place of supply of the compressed air supply source is also restricted due to the space for the passenger compartment. Installation in a fairly limited space is inevitable. Therefore, the rotary air compressor which concerns on a present Example provides an effective means.

(2) In the conventional rotary air compressor, since the noise-compacting main body, which is a noise source, has to be exposed to the outside, the magnitude of the noise is particularly a problem when used for railway vehicles. However, since the noise source is completely covered by a container having a soundproofing function, a significant noise reduction can be achieved.

(3) In addition, when used in a railway vehicle, the installation place is limited to the lower part of the vehicle as described above. In the conventional rotary air compressor, the piping flow is inevitably exposed to the outside. Foreign matters such as gravel and small stones scattered on the surface collided with the exposed pipes, and had a fatal defect that was easily damaged. In order to prevent this, measures such as providing a protector to cover the pipes further exposed to the outside world can be used, and in order to complicate the structure and increase the components, practical measures are to be taken. Things had been difficult. However, according to the present embodiment, since no pipes exposed to the outside are present at all, collisions with pipes such as small stones do not occur, and the above problems can be fundamentally solved.

(4) In addition, in the conventional rotary air compressor, in order to compact the apparatus, it is necessary to reduce the volume of the oil accumulating container, and to foam the oil and the air to a small extent. Since it became easy to do this, the problem of mixing oil into compressed air has arisen. However, in the rotary air compressor according to the present embodiment, since the apparatus can be greatly compacted by means of not miniaturizing the oil storage container, the problem of foaming is solved, and the amount of oil mixed into the compressed air can be reduced. It can be suppressed significantly. Further, in the present embodiment, since the structure of the pipe for discharging the compressed air containing the oil in the oil recovery container is improved, the effect of reducing the amount of oil content can be obtained.

In addition, embodiment is not limited to the above-mentioned thing, For example, you may change and implement as follows.

(1) The arrangement structure of the suction dust filter is not necessarily coaxial with the compressor main body, but is adjacent to the axis and the vertical direction if the purpose of achieving compactness can be achieved by occupying the space efficiently. You may do it. As a result, the rotary air compressor may be installed as a single suction dust filter without being removed from the vehicle body.

(2) Even if the suction valve can achieve the purpose of compactness, the suction valve may not necessarily be inserted into the oil recovery container, or may be provided so as to form an air suction path between the suction dust filter and the oil recovery container.

(3) If it is not used for railway vehicles or the like, the meaning of preventing collisions with pipes such as foreign matters is lost. For this reason, in this case, as long as the purpose of compaction is even achieved, the oil piping for supplying oil from the oil separation system to the compressor main body does not necessarily have to pass through the oil recovery container.

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

(5) The rotating body accommodated in the compressor main body may not be a screw type but may be, for example, a two lobe type, a vane type, a scroll type, or a rolling piston type.

According to the invention of claim 1, since the oil recovery container is provided on the side wall of the main body casing in which the compressor body is installed, the compressor body is structured to be contained in the oil recovery container. It is equivalent to saving the installation space of the compressor main body, and it is possible to realize a significantly smaller size. In addition, since the compressor body, which is the source of noise generation, is shielded from the outside by an oil recovery container, it is surrounded by a soundproof wall, so that the problem of low noise can be solved at once.

According to the invention of claim 2, since the oil piping path from the oil separation system to the supply port of oil installed in the compressor main body passes through the oil recovery container, the pipe is protected by the oil recovery container without exposing to the outside world, When used for a railroad car or the like, the problem of damage to the pipe due to foreign matter collision such as small stones can be solved. As a matter of course, it is not necessary to provide a protector or the like for pipes, and in addition to the case of claim 1, the effect can be further reduced.

According to the invention of claim 3, since the suction valve is fitted to both the suction port and the oil recovery container, the space for installing the suction valve arrangement can be efficiently installed, and in addition to the case of claim 1 or 2, it is more compact. It is effective to plan anger.

According to the invention of claim 4, the oil recovery container and the suction dust filter, the elements of which the outer shape is substantially cylindrical, are adjacent to each other in parallel with the compressor body in a direction coaxial to create an extra space. In addition, since it can be arranged so as to occupy space efficiently, in addition to the case of Claim 1 or 2, the effect which can aim at further compactness is achieved.

Claims (4)

A compressor body having a rotor for compressing air with oil, the compressor body having an air inlet, an outlet of compressed air containing oil, and an oil supply port, and connected to the rotor, A drive means for rotating the engine, a main body casing in which the drive means is accommodated, the main body casing having the side wall on which the compressor main body is installed, and the side wall to cover the compressor main body, and accumulating oil in the compressed air from the discharge port. An oil recovery vessel and an oil separation system for separating oil contained in the compressed air introduced into the main body casing and introduced into the main body casing, the communication passage leading to the suction port of the compressor main body in the oil recovery vessel; Rotary air compressor, characterized in that formed in the penetrating state. The rotary air compressor according to claim 1, wherein an oil pipe for returning oil from the oil separation system to the supply port via the oil recovery container is provided. 3. The rotary air according to claim 1 or 2, wherein the communication passage is formed by a sleeve fitted to both the suction port and the oil recovery container, and an intake valve is arranged in the sleeve. compressor. The rotary air compressor according to claim 1 or 2, wherein the suction dust filter in a direction coaxial with the compressor body is arranged adjacent to the oil recovery container.