EP3696409A1

EP3696409A1 - Air compression device

Info

Publication number: EP3696409A1
Application number: EP20156900.1A
Authority: EP
Inventors: Masaru Kuromitsu; Takashi Kuga; Keita Kawabata; Genpei TANAKA
Original assignee: Nabtesco Corp
Current assignee: Nabtesco Corp
Priority date: 2019-02-12
Filing date: 2020-02-12
Publication date: 2020-08-19
Also published as: JP2020133404A; JP7388817B2; CN111550410A

Abstract

An air compression device(100) includes: a compressor (10) that compresses air sucked from a suction path and deliver the air to a delivery path; a motor (12) that drives the compressor; a supply device (40) that supplies driving power to the motor; and a cooling unit (42) that is provided in at least a part of the suction path or at least a part of the delivery path to cool the supply device.

Description

The present invention relates to an air compression device.
An air compression device is known which generates compressed air. For example, JP 2016-075159 A describes a package type compressor including a compressor body driven by an electric motor. This compressor includes the compressor body that compresses air, a motor that drives the compressor body, an inverter that controls the rotational speed of the motor, and a cooling fan provided in the compressor body. The inverter is provided in an intake path of cooling air formed by the cooling fan.
The present inventors have obtained the following recognition about the air compression device.
A switching power supply, which configures a supply device that supplies power to the motor, such as an inverter and electronic components such as a smoothing capacitor self-heat during operation. In order to suppress the temperature rise of the electronic component, it is desirable that the supply device be cooled. In the compressor described in JP 2016-075159 A , an inverter is arranged in a duct, and the inverter is cooled when air sucked from a suction port of a housing is allowed to pass through the duct by a cooling fan provided in the compressor body. Although the supply device is required to be efficiently cooled for downsizing and the like, the compressor described in JP 2016-075159 A cannot fully satisfy this requirement.
From these, the present inventors have recognized that there is room for improvement in the viewpoint of efficiently cooling the supply device in the air compression device.
The present invention has been made in view of these problems, and an object of the present invention is to provide an air compression device that can efficiently cool a supply device that supplies electric power to a motor.
In order to solve the above problems, an air compression device according to one aspect of the present invention includes: a compressor that compresses air sucked from a suction path and deliver the air to a delivery path; a motor that drives the compressor; a supply device that supplies driving power to the motor; and a cooling unit that is provided in at least a part of the suction path or at least a part of the delivery path to cool the supply device.
In addition, the above arbitrary combinations or ones obtained by mutually replacing the constituent elements and expressions of the present invention between a method, a device, a program, a temporary or non-temporary storage medium recording the program, a system, and the like are effective as an embodiment of the present invention.
According to this invention, the air compression device can be provided which can cool efficiently the supply device which supplies electric power to a motor.

Fig. 1 is a system diagram schematically illustrating a configuration of an air compression device according to a first embodiment of the present invention;
Fig. 2 is a schematic view illustrating a state where the air compression device of Fig. 1 is installed in a railway vehicle;
Fig. 3 is a side sectional view schematically illustrating a periphery of a compressor driving part and a multiblade fan of the air compression device of Fig. 1;
Fig. 4 is an enlarged side sectional view illustrating a periphery of a labyrinth portion of the compressor driving part of Fig. 3;
Fig. 5 is a perspective view illustrating a periphery of an inverter control device of the air compression device of Fig. 1;
Fig. 6 is a front view illustrating a balance weight and a multiblade fan of the compressor driving part in Fig. 3;
Fig. 7 is a rear view illustrating the balance weight and the multiblade fan of the compressor driving part in Fig. 3;
Fig. 8 is a front view schematically illustrating a compressor and a blower fan of the air compression device of Fig. 1;
Fig. 9 is another front view schematically illustrating the compressor and the blower fan of the air compression device of Fig. 1;
Fig. 10 is a view schematically illustrating a flow of air from the blower fan of Fig. 8;
Fig. 11 is a perspective view schematically illustrating a cooler of the air compression device of Fig. 1 ;
Fig. 12 is a schematic view for explaining the flow of air in the cooler of Fig. 11;
Fig. 13 is a system diagram schematically illustrating a configuration of an air compression device according to a second embodiment of the present invention; and
Fig. 14 is a front view schematically illustrating a periphery of a compressor of an air compression device according to a first modification.

Hereinafter, a preferred embodiment of the invention will be described with reference to the accompanying drawings. In an embodiment and a modification, the same or equivalent components and members are denoted by the same reference numerals, and repeated description is appropriately omitted. In addition, the dimensions of the members in each drawing are appropriately enlarged or reduced for easy understanding. In addition, in the drawings, some of the members that are not important for describing the embodiment are omitted.
In addition, terms including ordinal numbers such as first and second are used to describe various components. However, this term is used only for the purpose of distinguishing one component from other components, and the components are not limited by the term.
With reference to the drawings, a configuration of an air compression device 100 according to a first embodiment of the present invention will be described. As an example, the air compression device 100 is provided under a floor of a railway vehicle and can be used as an air compression device for a railway vehicle which supplies compressed air to the vehicle. Fig. 1 is a system diagram schematically illustrating a configuration of the air compression device 100. Fig. 2 is a schematic view illustrating a state in which the air compression device 100 is installed in the railway vehicle 90. In this drawing, for easy understanding, a part of a bearing holder 38 and a multiblade fan 16 is fractured, and a blower fan 28 is shown smaller than an actual ratio.
The air compression device 100 of the present embodiment includes a compressor 10, a compressor driving part 14, a multiblade fan 16, a cooler 22, a dehumidifier 24, an air introduction unit 26, a blower fan 28, an air suction part 32, a compressed air delivery part 34, an inverter control device 40, and a housing case 36. The air compression device 100 compresses the air sucked from the air suction part 32 with the compressor 10, cools the air with the cooler 22, dehumidifies the air with the dehumidifier 24, sends the air out from the compressed air delivery part 34, and supplies the air to the vehicle 90.
The compressor driving part 14 drives the compressor 10. The inverter control device 40 drives the motor 12 of the compressor driving part 14. The multiblade fan 16 is driven by the motor 12 to generate an air flow used for cooling by the cooler 22. The air introduction unit 26 introduces compressed air to the motor 12, and the blower fan 28 generates an air flow that cools the compressor 10.
Hereinafter, the direction along the central axis La of the rotary shaft 10a of the compressor 10 is referred to as "axial direction", and the circumferential direction and the radial direction of the circle centered on the central axis La are respectively "circumferential direction" and "radial direction". Hereinafter, for convenience, one side (a right side in the drawing) in the axial direction is referred to as an input side, and the other side (a left side in the drawing) is referred to as a non-input side. In this example, the motor 12 is provided on the input side of the compressor 10, and the compressor 10 is provided on the non-input side of the motor 12.
The air suction part 32 is installed in the housing case 36 and functions as a mechanism for sucking air (outside air) compressed by the compressor 10. The air suction part 32 is formed so as to communicate with the compressor 10 through the suction pipe 32b. The air suction part 32 is provided with a suction filter 32a that suppresses the passage of dust such as sand dust when the suction air passes. The suction filter 32a may be a filter using a mesh.
The compressed air delivery part 34 functions as a mechanism that delivers the compressed air Ar10d cooled by the cooler 22 described later and dehumidified by the dehumidifier 24. The compressed air delivery part 34 supplies the generated compressed air Ar10d to the compressed air reservoir 92 installed outside the housing case 36.
The compressed air delivery part 34 may include a valve mechanism 34d provided in a path that allows the dehumidifier 24 and the compressed air reservoir 92 to communicate with each other. The valve mechanism 34d may be a check valve that allows the compressed air Ar10d to pass toward the compressed air reservoir 92 side and prevent backflow from the compressed air reservoir 92 when the dehumidifier 24 side is equal to or higher than a predetermined pressure.
The compressor driving part 14 will be described with reference to Figs. 2, 3, and 4. Fig. 3 is a side sectional view schematically illustrating the periphery of the compressor driving part 14 and the multiblade fan 16. Fig. 4 is an enlarged side sectional view illustrating the periphery of the labyrinth portion 12f of the compressor driving part 14. The compressor driving part 14 mainly includes a motor 12 that rotationally drives the compressor 10 and a balance weight 15.
The motor 12 will be described. The motor 12 includes an output shaft 12a, a rotor 12k, a stator 12s, a casing 12c, and a labyrinth portion 12f. In the present embodiment, the output shaft 12a of the motor 12 is provided integrally with the rotary shaft 10a of the compressor 10. The rotor 12k includes a magnet 12m having a plurality of magnetic poles in the circumferential direction and is fixed to the outer periphery of the output shaft 12a. The rotor 12k is fixed to an input side of a rotor fixing part 15d of the balance weight 15 described later by a fastener such as a bolt (not illustrated). An adhesive may be used in combination for these fixations.
The stator 12s includes a stator core 12j that surrounds the rotor 12k via a magnetic gap and a coil 12g that is wound around the stator core 12j. The outer periphery of the stator 12s is fixed to the inner peripheral surface of the casing 12c. The casing 12c includes a cylindrical portion 12d and a bottom portion 12e, and functions as an outer shell that surrounds the rotor 12k and the stator 12s. In this example, the casing 12c has a bottomed cylindrical shape in which the non-input side is opened and the bottom portion 12e is provided on the input side. The bottom portion 12e is provided with an introduction port 12h for taking in air from the air introduction unit 26.
The labyrinth portion 12f is provided so as to cover the non-input side of the cylindrical portion 12d, and has a disc shape in this example. The labyrinth portion 12f includes a rotating body portion 12n fixed to the output shaft 12a and a stationary body portion 12p fixed to the cylindrical portion 12d. The stationary body portion 12p is a donut-shaped disc member in which a stationary body side labyrinth forming part 12q is provided on the outer periphery of the non-input side end surface. The stationary body side labyrinth forming part 12q includes a stationary body side concave portion 12t and a stationary body side convex portion 12u. The labyrinth convex portion 15h described later enters the stationary body side concave portion 12t. The stationary body side convex portion 12u enters a labyrinth concave portion 15g described later. The stationary body side convex portion 12u is an annular wall provided on the inner peripheral side of the stationary body side concave portion 12t. The rotating body portion 12n also serves as the balance weight 15 described later. A labyrinth 12r is provided between the rotating body portion 12n and the stationary body portion 12p. In this example, the labyrinth 12r is a maze that combines bended spaces. The labyrinth portion 12f includes the labyrinth 12r to reduce the intrusion of dust into the motor 12.
Further, since the compressed air Ar10e introduced from the introduction port 12h flows outward from the labyrinth 12r, the dust in the labyrinth 12r is easily discharged outside by this air flow.
The motor 12 generates a field magnetic field in the magnetic gap when a drive current is provided to the coil 12g of the stator 12s from an inverter control device 40 (drive circuit) described later. The motor 12 generates a rotational driving force on the rotor 12k and the output shaft 12a due to the field magnetic field and the magnet 12m of the rotor 12k. The rotational driving force of the output shaft 12a drives the multiblade fan 16 and the compressor 10 through the rotary shaft 10a. The bearing that supports the rotary shaft 10a is provided in the bearing holder 38 outside the compressor driving part 14, and is not provided in the compressor driving part 14.
The cooling unit 42 and the inverter control device 40 will be described with reference to Figs. 1, 2, and 5. Fig. 5 is a perspective view illustrating the periphery of the inverter control device 40. In this drawing, in order to make the inside visible, the upper plate is removed, and a part of the facing wall 42b is cut away. As illustrated in Fig. 5, the cooling unit 42 of the present embodiment functions as a storage box for housing the inverter control device 40. The cooling unit 42 houses the inverter control device 40 to protect the inverter control device 40 from dust or rainwater. The cooling unit 42 of the present embodiment is a metal box in which a rectangular parallelepiped shape having six surfaces is sealed, and includes the facing walls 42b and 42d facing each other.
As illustrated in Figs. 1 and 2, the cooling unit 42 is provided in the suction path of the suction air Ar32, and introduces the suction air Ar32 from the suction path. In particular, the cooling unit 42 is provided on a path between the air suction part 32 and the suction port 10c of the compressor 10. That is, the filter 32a that suppresses the passage of dust is provided upstream of the cooling unit 42. In addition, a valve mechanism 32d (check valve) that allows air to flow to the compressor 10 is provided downstream of the cooling unit 42.
The inverter control device 40 functions as a supply device that supplies driving power to the motor 12 that drives the compressor 10. As illustrated in Fig. 5, the inverter control device 40 includes an electronic component 40p, a printed wiring board 40b, and a heat sink 40h. The electronic component 40p is a switching power module or a smoothing capacitor that supplies a drive current to the coil 12g of the motor 12. The printed wiring board 40b electrically connects the electronic component 40p to realize a predetermined electronic circuit and supports the electronic component 40p.
Since the electronic component 40p self-heats during operation, the inner temperature of the cooling unit 42 increases. When the inner temperature of the box increases, the internal temperature of the electronic component 40p increases with self-heating, resulting in a shortened life or failure. Therefore, the inverter control device 40 includes a heat sink 40h that cools the electronic component 40p. The heat sink 40h may be arranged in at least a part of the suction path or at least a part of the delivery path.
Although the heat sink 40h is not limited, the heat sink 40h in this example includes a flat base 40e attached to the printed wiring board 40b, and a plurality of fins 40f protruding from the base 40e to the opposite side of the printed wiring board 40b. Heat generated in the electronic component 40p is transmitted to the base 40e and the plurality of fins 40f through the wiring board 40b.
The cooling unit 42 is provided with an inlet portion 42p for introducing the suction air Ar32 and an outlet portion 42s for discharging the suction air Ar32. When the suction air Ar32 is introduced from the inlet portion 42p and discharged from the outlet portion 42s, the cooling unit 42 is forcibly ventilated, the temperature rise in the cooling unit 42 is suppressed, and the internal temperature of the electronic component 40p decreases.
The suction air Ar32 introduced into the cooling unit 42 forms an air flow that flows from the inlet portion 42p to the outlet portion 42s. It is desirable that the flow resistance of the air flow is small. For this reason, in the present embodiment, the inlet portion 42p is provided in one facing wall 42b, and the outlet portion 42s is provided in the other facing wall 42d. In particular, the inlet portion 42p and the outlet portion 42s are arranged at positions facing each other so that the distance therebetween is minimized. In the example of Fig. 5, the inlet portion 42p and the outlet portion 42s are arranged at the center in the width direction of the facing walls 42b and 42d.
In order to promote heat dissipation of the heat sink 40h, it is desirable that an air flow pass through the surfaces of the base 40e and the fins 40f. Therefore, in the present embodiment, the heat sink 40h is arranged in the air flow path in the cooling unit 42. In particular, the heat sink 40h is arranged such that a heat radiating surface 42m is in contact with the air flow in the storage box. In the example of Fig. 5, the base 40e and the fins 40f extend in the direction of the air flow of the cooling unit 42, and are arranged so as not to disturb the air flow. Specifically, the heat radiating surfaces 42m of the base 40e and the fins 40f are substantially parallel to the line connecting the inlet portion 42p and the outlet portion 42s so as to follow the air flow. In particular, the two fins 42f are arranged so as to sandwich a line connecting the inlet portion 42p and the outlet portion 42s, and the main flow (main large flow) of air flow is sandwiched between the two fins 42f so as to pass between the two fins 42f.
The multiblade fan 16 will be described with reference to Figs. 3, 4, 6, and 7. Fig. 6 is a front view illustrating the multiblade fan 16 fixed to the balance weight 15. Fig. 7 is a rear view illustrating the multiblade fan 16 fixed to the balance weight 15. The multiblade fan 16 is arranged between the compressor 10 and the motor 12 in the axial direction. The multiblade fan 16 functions as a fan that rotates integrally with the rotor 12k of the motor 12. In particular, the multiblade fan 16 functions as a blower that collects and sends the air flow generated from the central portion toward the outer periphery in a delivery duct 16d. The multiblade fan 16 may be referred to as a sirocco fan. The multiblade fan 16 includes a disc portion 16b and a plurality of blades 16c.
The disc portion 16b is a donut-shaped disc member of which the inner peripheral side is fixed to the rotary shaft 10a via a balance weight 15. In particular, the disc portion 16b is fixed to a fan fixing part 15c provided on the non-input side end surface of the balance weight 15 with a fastener such as a bolt (not illustrated). An adhesive may be used in combination for these fixations. The plurality of blades 16c extend from the disc portion 16b to the non-input side in the vicinity of the outer periphery of the disc portion 16b. The plurality of blades 16c are arranged at predetermined angles in the circumferential direction. The plurality of blades 16c function as an air flow generation part that generates an air flow toward the outer periphery by rotating. The casing 16e is a cylindrical member that surrounds the disc portion 16b and the plurality of blades 16c.
As illustrated in Fig. 4, the disc portion 16b is arranged on the non-input side end surface of the motor 12 with an axial gap 16g interposed therebetween. The width W16 of the axial gap 16g may be narrower than the thickness H16 of the disc portion 16b. As illustrated in Fig. 3, in the axial direction, the blade 16c overlaps a second bearing 13e in the axial direction.
The delivery duct 16d is a cylindrical member extending from the casing 16e to the cooler 22. A lower portion 16h of the delivery duct 16d is a substantially rectangular tube-shaped portion extending upward from the upper portion of the casing 16e. An upper portion 16j of the delivery duct 16d is a portion that communicates with the lower portion of the cooler 22 from the upper portion of the lower portion 16h. The upper portion 16j has a substantially quadrangular pyramid shape with a wide upper side.
The multiblade fan 16 may overlap with at least a part of a bearing 38j that supports the rotary shaft 10a of the compressor 10 in the axial direction. In this case, the axial length of the air compression device 100 can be shortened compared to the case where the multiblade fan 16 does not overlap the bearing 38j.
The balance weight 15 will be described with reference to Figs. 6 and 7. The balance weight 15 also functions as an intermediate member arranged between the rotor 12k and the multiblade fan 16. The balance weight 15 is a disc-shaped member made of metal such as brass, and also serves as the rotating body portion 12n of the labyrinth portion 12f as described above. The balance weight 15 includes balance adjusting units 15a and 15b, a fan fixing part 15c, a rotor fixing part 15d, a shaft fastening part 15f, and a labyrinth forming part 15e.
The fan fixing part 15c is an annular portion to which the multiblade fan 16 is fixed on the end surface on the non-input side. The rotor fixing part 15d is an annular portion to which the rotor 12k is fixed on the input side end surface, and in this example, has a cylindrical outer shape protruding from the outer periphery to the input side. The shaft fastening part 15f is a through hole into which the output shaft 12a is inserted and fixed.
The labyrinth forming part 15e is a portion where the labyrinth concave portion 15g and the labyrinth convex portion 15h are provided in the outer periphery of the input side end surface. The labyrinth concave portion 15g is an annular concave portion formed on the non-input side in the labyrinth forming part 15e. The stationary body side convex portion 12u enters the labyrinth concave portion 15g through a gap. The labyrinth convex portion 15h is a portion that enters the stationary body side concave portion 12t through a gap. The labyrinth convex portion 15h in this example is an annular wall provided so as to surround the outer peripheral side of the labyrinth concave portion 15g.
The balance adjusting units 15a and 15b are portions that are subjected to processing for reducing the total unbalance amount of the balance weight 15, the rotor 12k, and the multiblade fan 16. That is, in a state where the multiblade fan 16 and the rotor 12k are fixed and integrated with the balance weight 15, the balance adjusting units 15a and 15b are subjected to balance adjustment for reducing the total unbalance amount.
The balance adjusting units 15a and 15b may be provided only on one end surface of the balance weight 15. However, in the present embodiment, the balance adjusting units 15a and 15b are provided on both end surfaces. The balance adjusting units 15a and 15b include a fan side adjusting part 15a provided on the radially inner side from the fan fixing part 15c and a rotor side adjusting part 15b provided on the radially outer side from the rotor fixing part 15d. In particular, the balance adjusting unit 15a may be provided on the radially inner side from the air flow generation part of the multiblade fan 16. In this example, the balance adjusting unit 15a is provided on the radially inner side from the plurality of blades 16c. As illustrated in Figs. 6 and 7, the balance adjusting units 15a and 15b in this example are flat annular portions in the radial intermediate region of the balance weight 15.
The compressor 10 will be described with reference to Figs. 2 and 8 to 10. These drawings illustrate the compressor 10 and the blower fan 28 as viewed from the arrow F in Fig. 2. Fig. 8 is a front view schematically illustrating the compressor 10 and the blower fan 28. Fig. 9 illustrates a state where a fixed scroll portion 10j is removed. Fig. 10 illustrates a back space 10g with an orbiting scroll portion 10h removed. The compressor 10 of the present embodiment is a scroll type air compressor which includes a rotary shaft 10a, a body portion 10b, a suction port 10c, a discharge port 10e, an air cooling fin 10f, an orbiting scroll portion 10h, a fixed scroll portion 10j, and a back space 10g.
In the compressor 10, the suction port 10c communicates with the air suction part 32, and compresses the air Ar32 sucked into the pump space 10d from the air suction part 32 through the suction pipe 32b. The valve mechanism 32d is provided between the air suction part 32 and the suction port 10c of the compressor 10. The valve mechanism 32d opens when the compressor 10 is operated and the compressor 10 side becomes negative pressure. The discharge port 10e communicates with the cooler 22, and the compressed air is discharged from the discharge port 10e to the cooler 22.
The body portion 10b is a circumferential outer peripheral wall that defines the pump space 10d. The body portion 10b surrounds a fixed scroll 10m and an orbiting scroll 10n in the pump space 10d. The fixed scroll portion 10j includes a fixed disc portion 10k provided with a plurality of air cooling fins 10f on the outside and a fixed scroll 10m fixed inside the fixed disc portion 10k. The discharge port 10e is provided at the center of the fixed disc portion 10k. The orbiting scroll portion 10h includes an orbiting disc portion 10p and an orbiting scroll 10n fixed to the orbiting disc portion 10p. The rotary shaft 10a extending to the input side is fixed at the center of the orbiting disc portion 10p. The back space 10g is provided on the input side of the orbiting disc portion 10p, that is, on the back side of the orbiting scroll portion 10h. Cooling air is introduced from the blower fan 28 into the back space 10g, and the orbiting disc portion 10p and the rotary shaft 10a are forcibly cooled by air. The blower fan 28 will be described later.
The orbiting scroll 10n and the fixed scroll 10m are spiral bodies having the same shape. The compressor 10 compresses air when the volume of the compression space is changed by orbiting the orbiting scroll 10n integrally with the rotary shaft 10a with respect to the fixed scroll 10m. The compressor 10 sucks air from the outer periphery and performs compression toward the center. The compressor 10 may be an oil-free type.
The blower fan 28 will be described with reference to Figs. 2 and 8 to 10. The blower fan 28 is a blower mechanism that delivers cooling air (hereinafter referred to as a cooling air Ar28) to the compressor 10. The blower fan 28 supplies the cooling air Ar28 to the back space 10g on the back side of the orbiting scroll portion 10h to mainly cool the orbiting scroll portion 10h.
The blower fan 28 of the present embodiment is an electric axial flow blower having a propeller 28b. As illustrated in Fig. 10, the blower fan 28 is arranged on the side of the compressor 10 so that the rotation axis L28 of the propeller 28b is orthogonal to the rotary shaft 10a of the compressor 10. An outside air filter 28a formed of a wire mesh or the like is provided on the upstream side of the blower fan 28. A blower duct 28g for guiding the cooling air Ar28 to the central portion of the orbiting scroll portion 10h is provided on the downstream side of the blower fan 28.
The blower duct 28g has a substantially quadrangular frustum shape of which the cross-sectional area decreases toward the compressor 10 is approached. The cooling air Ar28 is throttled along the inner surface of the blower duct 28g and cools the central portion of the orbiting scroll portion 10h intensively. Since the temperature of the central portion of the orbiting scroll portion 10h is the highest, the cooling effect can be enhanced by intensively cooling the center portion. An exhaust duct 28h is provided on the downstream side of the back space 10g. In this example, the upstream side of the exhaust duct 28h faces the blower duct 28g, and the downstream side is directed downward.
The cooler 22 will be described with reference to Figs. 2, 3, 11, and 12. The cooler 22 cools the compressed air supplied from the compressor 10 at a high temperature (for example, 200°C to 250°C) to a temperature slightly higher than the room temperature (for example, 40°C to 50°C) and supplies the compressed air to the dehumidifier 24. The cooler 22 may be configured as a single cooler. However, in the present embodiment, a plurality of coolers are connected in series. The cooler 22 of the present embodiment includes a first cooler 18 that primarily cools the compressed air from the compressor 10 and a second cooler 20 that secondarily cools the compressed air cooled by the first cooler 18.
The first cooler 18 and the second cooler 20 have bent pipes 18p and 20p and pipe housing parts 18c and 20c for housing the pipes, respectively. The bent pipes 18p and 20p meander so that they have a plurality of bent portions, and compressed air flows from one end of the pipe toward the other end. The pipe housing parts 18c and 20c have vertically thin rectangular tube-shaped outer walls, and function as a wind tunnel for allowing a cooling air to flow vertically.
Wire mesh portions 18m and 20m for supporting the bent pipes 18p and 20p are fixed to the lower portions of the pipe housing parts 18c and 20c. The upper surface of the pipe housing part 20c is opened, and the wire mesh portion 20n is fixed to the upper surface of the pipe housing part 18c. As described above, the pipe housing parts 18c and 20c have a configuration in which the air flow easily passes vertically.
The first introduction part 18b provided at one end of the bent pipe 18p protrudes outside from the side wall of the pipe housing part 18c of the first cooler 18. The first introduction part 18b communicates with the discharge port 10e of the compressor 10. A first lead-out part 18e provided at the other end of the bent pipe 18p protrudes outside from the side wall of the pipe housing part 18c of the first cooler 18. The first lead-out part 18e communicates with a second introduction part 20b.
The second introduction part 20b provided at one end of the bent pipe 20p protrudes outside from the bottom of the pipe housing part 20c of the second cooler 20. The second introduction part 20b communicates with the first lead-out part 18e. A second lead-out part 20e provided at the other end of the bent pipe 20p protrudes outside from the side wall of the pipe housing part 20c of the second cooler 20. The second lead-out part 20e communicates with the dehumidifier 24.
The pipe housing part 18c is arranged on the upper side of the pipe housing part 20c. The air flow Ar16a delivered from the multiblade fan 16 is supplied to the lower surface of the pipe housing part 20c through the duct 16d. The air flow Ar16a flows through the gap of the wire mesh portion 20m and the gap of the bent pipe 20p, and is discharged from the upper surface of the pipe housing part 20c. As the air flow Ar16a passes through the outer peripheral surface of the bent pipe 20p, the compressed air of the bent pipe 20p is cooled.
The air flow Ar16b discharged from the pipe housing part 20c is supplied to the lower surface of the pipe housing part 18c. The air flow Ar16b flows through the gap of the wire mesh portion 18m, the gap of the bent pipe 18p, and the gap of the wire mesh portion 20n, and is discharged from the upper surface of the pipe housing part 18c. The compressed air Ar20c of the bent pipe 18p is cooled by the air flow Ar16b passing through the outer peripheral surface of the bent pipe 18p. The air discharged from the pipe housing part 18c is diffused into the atmosphere.
As described above, the air flow Ar16a delivered from the multiblade fan 16 is supplied to the second cooler 20 first and is used for secondary cooling of the compressed air after the primary cooling. The air flow Ar16b discharged from the second cooler 20 is supplied to the first cooler 18 and is used for primary cooling of the compressed air. Compared to the case where the air flow Ar16a is used for the primary cooling first, the temperature difference between the compressed air and the cooling air in the secondary cooling becomes large, so that the cooling efficiency can be increased.
The cooler 22 may be arranged anywhere as long as a desired cooling effect is obtained. The cooler 22 of the present embodiment is arranged above the center of the air compression device 100 in the vertical direction. In particular, the cooler 22 is arranged between the multiblade fan 16 and the floor of the railway vehicle 90. By shortening the path of the air flow Ar16a delivered from the multiblade fan 16, an extra piping space can be saved. Further, the longitudinal length of the air compression device 100 can be shortened compared to the case of being arranged in the longitudinal direction of the multiblade fan 16.
The dehumidifier 24 is provided in a path that allows the cooler 22 and the compressed air delivery part 34 to communicate with each other. The dehumidifier 24 is a hollow fiber membrane type dehumidifier that dehumidifies the cooled compressed air Ar10c. The dehumidifier 24 may include a filter element that includes a desiccant. In the dehumidifier 24, final dehumidification is performed on the compressed air Ar10d delivered from the compressed air delivery part 34. The compressed air Ar10d is delivered to the compressed air reservoir 92 via the compressed air delivery part 34.
The air introduction unit 26 introduces the compressed air Ar10d dehumidified by the dehumidifier 24 into the casing 12c of the motor 12. When the compressed air Ar10d is introduced to make the pressure inside the casing 12c a positive pressure higher than the external pressure, it is possible to reduce the intrusion of dust. The air introduction unit 26 delivers the compressed air Ar10d to the introduction port 12h provided in the bottom portion 12e. The air introduction unit 26 is provided with a valve mechanism 26d on a path for guiding the compressed air Ar10d from the dehumidifier 24 to the casing 12c. The valve mechanism 26d may be a check valve that allows the compressed air Ar10d to pass to the casing 12c side and block backflow from the casing 12c to the dehumidifier 24 when the dehumidifier 24 side is equal to or higher than a predetermined pressure.
The bearing holder 38 will be described with reference to Figs. 2 and 3. The bearing holder 38 is a portion that is provided on the input side of the compressor 10 and supports bearings 38h and 38j that rotatably support the rotary shaft 10a. The bearing holder 38 has a hollow cylindrical portion 38a and a plurality of fins 38f extending radially outward from the cylindrical portion 38a. The fin 38f has a triangular shape of which radially outer end extends radially outward as it approaches the compressor 10 in the axial direction. In this example, four fins 38f are provided at 90° intervals in the circumferential direction on the outer periphery of the cylindrical portion 38a. The bearing holder 38 also has a function of radiating heat generated in the compressor 10 to suppress an excessive temperature rise of the bearings 38h and 38j.
The bearings 38h and 38j include a first bearing 38h arranged near the compressor 10 and a second bearing 38j arranged near the motor 12. The first and second bearings 38h and 38j rotatably supports the rotary shaft 10a. The first and second bearings 38h and 38j are held in the hollow portion of the cylindrical portion 38a while being separated in the axial direction.
A part of the bearing holder 38 enters the inner peripheral portion of the multiblade fan 16 in the axial direction. Further, at least a part of the bearing 38j that supports the rotary shaft 10a of the compressor 10 overlaps the multiblade fan 16 in the axial direction. In this case, the axial space can be used more effectively than the case of no overlap.
The housing case 36 houses the compressor 10, the compressor driving part 14, the multiblade fan 16, the cooler 22, the dehumidifier 24, the air introduction unit 26, the blower fan 28, the air suction part 32, the compressed air delivery part 34, and the cooling unit 42 of the inverter control device 40.
The outline of one aspect of the present invention is as follows. The air compression device 100 according to one aspect of the present invention includes: the compressor that compresses air sucked from the suction path and deliver the air to the delivery path; the motor that drives the compressor; the supply device that supplies driving power to the motor; and the cooling unit 42 that is provided in at least a part of the suction path or at least a part of the delivery path to cool the supply device.
According to this aspect, the inside of the cooling unit 42 is forcibly ventilated by the introduced air, and the temperature rise of the inverter control device 40 is suppressed, thereby extending the life of the electronic component 40p. Since the inside of the cooling unit 42 is forcibly ventilated, it is not necessary to provide a space in the box, and the cooling unit 42 can be downsized.
The inverter control device 40 may include the heat sink 40h arranged in at least a part of the suction path or at least a part of the delivery path. In this case, the heat sink is efficiently cooled by the introduced air, and the temperature rise of the inverter control device 40 can be further suppressed.
The cooling unit 42 may be provided in the suction path, and a filter that suppresses the passage of dust may be provided upstream of the cooling unit 42. In this case, the dust entering the cooling unit 42 can be reduced.
A check valve that allows air flow from the cooling unit 42 to the compressor 10 and prevent air flow from the compressor 10 to the cooling unit 42 may be provided. In this case, backflow from the compressor 10 to the cooling unit 42 can be prevented.
The air compression device 100 may be a railway vehicle air compression device arranged below the floor of the railway vehicle 90. In this case, compressed air can be supplied to the railway vehicle 90. Further, since the inside of the cooling unit 42 is forcibly ventilated, it is not necessary to provide a space in the box, and the cooling unit 42 can be downsized. For this reason, the air compression device 100 can be easily arranged in the underfloor space of the railway vehicle 90, and there can be room in the underfloor space.
The above is the description of the first embodiment.
The air compression device 100 according to a second embodiment of the present invention will be described with reference to Fig. 13. Fig. 13 is a system diagram schematically illustrating the configuration of the air compression device 100 according to the second embodiment, and corresponds to Fig. 1. As illustrated in this drawing, the present embodiment is different from the first embodiment in that the cooling unit 42 introduces air from the delivery path of the compressor 10. That is, the compressed air Ar10d is introduced into the cooling unit 42 instead of the suction air Ar32. Therefore, the above description of the cooling unit 42 and the inverter control device 40 can be applied to the present embodiment by replacing the suction air Ar32 with the compressed air Ar10d.
The cooling unit 42 may be provided in any of the delivery path of the compressed air, but the cooling unit 42 of the present embodiment is provided on the downstream side of the valve mechanism 34d (check valve). Therefore, as illustrated in Fig. 13, the cooler 22 for cooling the air is provided upstream of the cooling unit 42. In this case, since the air cooled by the cooler 22 can be introduced into the cooling unit 42, the rise of the inner temperature of the box can be further suppressed.
Further, as illustrated in Fig. 13, the dehumidifier 24 that dehumidifies air is provided between the cooling unit 42 and the cooler 22. In this case, since the air dehumidified by the dehumidifier 24 can be introduced into the cooling unit 42, condensation in the box can be prevented.
Further, as illustrated in Fig. 13, the valve mechanism 34d (check valve) is provided which allows air flow from the upstream of the cooling unit 42 to the cooling unit 42 and prevents air flow from the cooling unit 42 to the upstream thereof. In this case, the backflow from the cooling unit 42 to the dehumidifier 24 can be prevented.
According to the present embodiment, the same operations and effects as in the first embodiment are achieved.
The above is the description of the second embodiment.
A third embodiment of the present invention is an air compression device. The air compression device 100 includes the compressor 10 that compresses suction air and deliver out the compressed air, and cools electronic components using the suction air or the compressed air. The electronic component may be the electronic component 40p of the inverter control device 40, or may be an electronic component configuring an electronic circuit different from the inverter control device 40. A method of air-cooling the electronic component may be such that the cooling air is brought into contact with the heat sink attached to the electronic component, or may be such that the cooling air is brought into direct contact with the electronic component. This cooling may be performed in a closed space such as a box, or may be performed in a partially or fully open space.
According to the present embodiment, the same operations and effects as in the first embodiment are achieved.
The above is the description of the third embodiment.
In the above, the example of embodiment of this invention was described in detail. Each of the above-described embodiments is merely a specific example for carrying out the present invention. The contents of the embodiments do not limit the technical scope of the present invention, and many design changes such as changes, additions, and deletions of constituent elements are possible without departing from the spirit of the invention defined in the claims. In the above-described embodiments, the contents that allow such a design change have been described with the notation of "of embodiment", "in the embodiment", or the like. However, design changes are not unacceptable for content without such notation.
Hereinafter, modifications will be described. In the drawings and descriptions of the modifications, the same reference numerals are given to the same or equivalent components and members as those in the embodiment. The description overlapping with the embodiment will be omitted as appropriate, and the configuration different from the first embodiment will be mainly described.

First modification

With reference to Fig. 14, an air compression device 200 according to a first modification will be described. This modification is different from the embodiment in that a supercharger 210 is provided at the suction port of the compressor 10 and is the same in the other configuration. Thus, the supercharger 210 will be described mainly. Fig. 14 is a front view illustrating the periphery of the compressor 10 and corresponds to Fig. 8.
In the scroll compressor, since the outer periphery has a negative pressure, it is easy to suck dust due to a pressure difference between the outside and the inside. In order to reduce the intrusion of dust, the compressor 10 is provided with a face seal (not illustrated) that seals the outer peripheral surface. However, the face seal has a gap called a joint portion, and dust enters through this gap. For this reason, in this modification, the supercharger 210 is provided at the suction port 10c of the compressor 10.
The supercharger 210 is not particularly limited as long as the supercharger can increase the internal pressure of the compressor 10. The supercharger 210 of this modification has an impeller 210b that is rotated by a motor 210m. The supercharger 210 pressurizes the upstream air, makes the downstream air equal to or higher than the atmospheric pressure, and supplies the air to the suction port 10c of the compressor 10. The supercharger 210 is provided in the path between the valve mechanism 32d and the suction port 10c. By providing the supercharger 210, it is possible to increase the internal pressure in the vicinity of the suction port 10c of the compressor 10, that is, the outer periphery of the compressor 10, and to suppress the intrusion of dust due to negative pressure.
In the description of the embodiment, an example is described in which all the air flowing through the suction path or the delivery path passes through the cooling unit 42, but the invention is not limited to this. For example, the cooling unit 42 may be configured such that a part of the air flowing through the suction path or the delivery path passes therethrough. That is, a path that bypasses a part of the air in parallel with the cooling unit 42 may be provided.
In the description of the embodiment, an example is described in which all the air that has passed through the cooling unit 42 is returned to the original path, but the invention is not limited thereto. For example, a part or all of the air that has passed through the cooling unit 42 may be discharged to the outside air without returning to the original path.
In the description of the embodiment, an example is described in which the motor 12 is a surface magnet type DC brushless motor, but the invention is not limited to this. The motor may be any motor as long as the motor can drive the compressor. For example, the motor may be another type of motor such as a magnet-embedded motor, an AC motor, a brushed motor, or a geared motor.
In the description of the embodiment, an example in which the supply device is the inverter control device 40 is described, but the invention is not limited to this. The supply device may be any device as long as the device can supply power to the motor. For example, the supply device may be a PLC (Programmable Logic Controller) that supplies power to the motor. The PLC may be referred to as a programmable controller or a sequencer.
In the description of the embodiment, an example is described in which the output shaft 12a of the motor 12 is integrated with the rotary shaft 10a of the compressor 10, but the invention is not limited to this. For example, the output shaft of the motor may be separated from the rotary shaft of the compressor and connected by a coupling or the like.
In the description of the embodiment, the motor 12 is described which does not include a bearing and in which the stator and the rotor are built in. However, the invention is not limited to this. For example, the motor may be one in which a bearing, a rotor, and a stator are integrated in a motor case.
In the description of the embodiment, an example is described in which the valve mechanism 26d is a check valve, but the invention is not limited to this. For example, the valve mechanism 26d may be a secondary pressure adjusting valve (pressure reducing valve) capable of adjusting the pressure on the secondary side.
In the description of the embodiment, an example is described in which the compressor 10 is a scroll type, but the invention is not limited to this. The compressor may be any compressor as long as the compressor can generate compressed air. For example, the compressor may be another type of air compressor such as a screw type or a reciprocating type.
The above-described modification has the same operations and effects as those of the first embodiment.
Any combination of the above-described embodiments and modifications is also useful as an embodiment of the present invention. The new embodiment made by the combination has the effects of the combined embodiment and modifications.

Claims

An air compression device (100) comprising:
a compressor (10) that compresses air sucked from a suction path and deliver the air to a delivery path ;

a motor (12) that drives the compressor;

a supply device (40) that supplies driving power to the motor; and

a cooling unit (42) that is provided in at least a part of the suction path or in at least a part of the delivery path and that cools the supply device.
The air compression device according to claim 1, wherein
the supply device includes a heat sink in at least a part of the suction path or at least a part of the delivery path.
The air compression device according to claim 1 or 2, wherein
the cooling unit is provided in the suction path, and
a filter (32a) that suppresses passage of dust is provided upstream of the cooling unit.
The air compression device according to claim 3, further comprising:
a check valve (32d) that allows air flow from the cooling unit to the compressor and prevent air flow from the compressor to the cooling unit.
The air compression device according to claim 1 or 2, wherein
the cooling unit is provided in the delivery path, and
a cooler (22) that cools air is provided upstream of the cooling unit.
The air compression device according to claim 5, wherein
a dehumidifier (24) that dehumidifies air is provided between the cooling unit and the cooler.
The air compression device according to claim 5 or 6, further comprising:
a check valve (34d) that allows an air flow from an upstream of the cooling unit to the cooling unit and prevent an air flow from the cooling unit to the upstream of the cooling unit.