KR20220096567A - Inverter integrated air compressor - Google Patents

Abstract

The present invention relates to an inverter-integrated air compressor. After partial air flows from an air discharging side of an impeller into a motor housing through a gap between a motor housing and the impeller, the air cools the inside of a motor. The air used to cool the motor is cooled by passing through a first air cooling unit and a second air cooling unit, integrally formed in the motor, in order. The cooled air flows into an air inlet of the impeller through a return pipe. An inverter including a PCB substrate and an IGBT combined with the PCB substrate is arranged on the outer circumference of the motor housing. Accordingly, the inverter-integrated air compressor does not discharge cooled air to the outside of the air compressor and effectively cools the motor, a bearing, and the like. Also, the inverter-integrated air compressor can be manufactured in a compact size and easily cool the inverter.

Description

Inverter integrated air compressor

The present invention relates to an inverter-integrated air compressor in which an inverter is integrally incorporated in an air compressor for compressing and sending air sucked in by rotation of an impeller.

The air compressor is a mechanical device that generates the energy of the fluid so that the suctioned fluid can be supplied by increasing the pressure using the impeller. In addition, an air compressor is generally provided with a high-speed motor capable of rotating at a high speed by an inverter, and an airfoil journal bearing and an airfoil thrust bearing are mounted for high-speed rotation.

Such an air compressor is composed of a main body forming an exterior, a driving unit including an impeller provided inside the main body to pressurize the sucked air, and a control unit capable of controlling the same, and is introduced into the interior of the main body through an air intake formed in the main body. The air is configured to be pressurized above a certain pressure through the impeller and then discharged through the air outlet.

Here, since the air compressor rotates at a higher speed than a general motor, a lot of heat is generated in the air foil bearings and a lot of heat is also generated in the rotor and stator of the motor, so cooling is essential.

To this end, the conventional air compressor has a cooling passage structure for cooling, but it is difficult to effectively cool the motor and each air foil bearing. Accordingly, there is a cooling passage structure that can improve the cooling efficiency of the internal components of the air compressor. need.

In general, brushless direct current (BLDC) is used in the air compressor, and an inverter is integrally mounted to control the BLDC motor. However, in the inverter-integrated air compressor, an impeller is mounted on one side of a rotating shaft, and an inverter is provided at a position opposite to the impeller for cooling the inverter. Accordingly, the overall length of the air compressor is increased, making it difficult to make a compact configuration and it is difficult to cool the inverter.

KR 10-2020-0081251 A (2020.07.07.)

The present invention has been devised to solve the above-described problems, and an object of the present invention is to effectively cool the motor and bearings without discharging the cooling air that has cooled the motor to the outside of the air compressor, as well as the inverter To provide an inverter-integrated air compressor that can manufacture an air compressor integrally provided with a compact size and facilitates cooling of the inverter.

Inverter-integrated air compressor of the present invention for achieving the object as described above, the motor housing having a stator and a rotor therein, the rotor is rotatably coupled; an impeller housing coupled to one side of the motor housing, having an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing; an impeller provided inside the impeller housing and coupled to one end of the rotor; First air coupled to the other side of the motor housing, a first cooling air flow path is formed therein, an inlet and an outlet communicating with the first cooling air flow path are formed, the inlet communicating with the inside of the motor housing cooling unit; a cooling water passage passing through the motor housing and a second cooling air passage passing through the motor housing adjacent to the cooling water passage, wherein one end of the second cooling air passage is connected to an outlet of the first cooling air passage 2 air cooling unit; a return pipe having one end connected to the other end of the second cooling air flow path and the other end connected to the air inlet of the impeller housing; and an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing; may be included.

In addition, in the inverter, the PCB substrate and the IGBT may be arranged parallel to the central axis direction of the motor housing, and the PCB substrate and the IGBT may be arranged at a specific angle.

In addition, the coolant flow path may be formed in a corrugate shape along a circumferential direction of the motor housing.

In addition, the inverter further includes a cooling plate connected to the cooling water flow path, wherein the IGBT is interposed between the motor housing and the cooling plate, so that one surface of the IGBT is in contact with the outer peripheral surface of the motor housing and the other surface is a cooling plate can be in contact with

In addition, the air introduced into the motor housing through the gap between the impeller and the motor housing on the air discharge side of the impeller is heated by heat exchange with the stator and the rotor while passing through the motor housing, and then the first air The air is firstly cooled by flowing into the cooling unit and radiating heat to the outside. After that, the air passes through the second air cooling unit and is secondarily cooled by the cooling water, and then air flows into the air inlet of the impeller housing through the return pipe. can be

In addition, the first air cooling unit may have a plurality of heat dissipation fins protruding from an inner surface forming the first cooling air flow path.

In addition, a pair of air foil journal bearings coupled to the bearing mounting portions formed on both sides of the motor housing, spaced apart from both sides of the rotor, and supporting a radial load so that the rotor is rotatable; a thrust runner coupled to the other end of the rotor and disposed between the other bearing mounting part of the motor housing and the first air cooling part; and a pair of air foil thrust bearings interposed between a bearing mounting portion adjacent to the thrust runner and the thrust runner and between the thrust runner and the first air cooling portion to support an axial load so that the thrust runner is rotatable. It may be made to further include.

In addition, the air passing through the gap between the impeller and the motor housing on the air discharge side of the impeller is an air foil journal bearing disposed on one side, an air foil journal bearing disposed on the other side, between the stator and the rotor, the pair of After passing through one or more air foil thrust bearings among the air foil thrust bearings in turn, the air may be introduced into the first cooling unit.

In addition, through-holes penetrating both surfaces are formed in the bearing mounting portions on both sides of the motor housing, and the air passing through the gap between the impeller and the motor housing on the air discharge side of the impeller is an air foil journal bearing disposed on one side and the one side of the motor housing. It is branched to pass through the through hole, and the air that has passed between the stator and the rotor may be branched to pass through the air foil journal bearing disposed on the other side and the through hole of the other side.

In addition, the first air cooling unit may have an opening penetrating inside and outside the central portion of a side surface facing the thrust runner, and the opening may communicate with an air foil thrust bearing side disposed on the other side of the thrust runner. .

In addition, the inverter-integrated air compressor of the present invention includes: a motor housing having a stator and a rotor therein, the rotor is rotatably coupled, and a coolant passage passing therein; an impeller housing coupled to one side of the motor housing, having an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing; an impeller provided inside the impeller housing and coupled to one end of the rotor; an air cooling unit coupled to the other side of the motor housing, having a cooling air passage formed therein, an inlet and an outlet communicating with the cooling air passage, the inlet communicating with the inside of the motor housing; and an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing; Including, the outlet of the air cooling unit is formed through the inside and the outside in the central portion of the side facing the rotation shaft of the rotor, the rotation shaft of the rotor is formed with a return flow passage penetrating both sides in the axial direction Thus, one end of the return passage may be connected to the outlet of the air cooling unit and the other end may be connected to the air inlet of the impeller housing.

In addition, the inverter-integrated air compressor of the present invention includes: a motor housing having a stator and a rotor therein, the rotor is rotatably coupled, and a cooling water passage passing through the motor housing; a first impeller housing coupled to one side of the motor housing, an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing; a first impeller provided inside the impeller housing and coupled to one end of the rotor; First air coupled to the other side of the motor housing, a first cooling air flow path is formed therein, an inlet and an outlet communicating with the first cooling air flow path are formed, the inlet communicating with the inside of the motor housing cooling unit; a cooling water passage passing through the motor housing and a second cooling air passage passing through the motor housing adjacent to the cooling water passage, wherein one end of the second cooling air passage is connected to an outlet of the first cooling air passage 2 air cooling unit; a return pipe having one end connected to the other end of the second cooling air flow path and the other end connected to the air inlet of the impeller housing; a second impeller housing coupled to the outside of the first air cooling unit on the other side of the motor housing and having an air inlet and an air outlet communicating with the inside; a second impeller provided inside the impeller housing and coupled to the other end of the rotor; and an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing; may be included.

In the inverter-integrated air compressor of the present invention, the cooling effect of the stator and rotor of the motor, the airfoil journal bearing and the airfoil thrust bearing is improved, and the cooling air that has cooled the inside of the motor is not discharged to the outside of the air compressor. may not be contaminated, and there is an advantage in that there is no need for a separate air exhaust structure in the facility or installation space where the air compressor is installed.

In addition, an air compressor having an inverter integrated therein can be manufactured in a compact size, and there is an advantage of easy cooling of the inverter.

1 to 4 are a perspective view, a left side view, a front view, and a right side view showing an inverter-integrated air compressor according to a first embodiment of the present invention.
5 and 6 are a plan cross-sectional view and a front cross-sectional view of an inverter-integrated air compressor according to the first embodiment of the present invention.
7 is a perspective view illustrating a PCB board and an IGBT of the inverter-integrated air compressor according to the first embodiment of the present invention.
8 is a top plan view showing a state in which the upper cover of the inverter-integrated air compressor according to the first embodiment of the present invention is removed.
9 is a plan cross-sectional view showing an inverter-integrated air compressor according to a second embodiment of the present invention.
10 is a plan cross-sectional view showing an inverter-integrated air compressor according to a third embodiment of the present invention.

Hereinafter, the inverter integrated air compressor of the present invention as described above will be described in detail with reference to the accompanying drawings.

<Example 1>

1 to 4 are a perspective view, a left side view, a front view, and a right side view showing an inverter-integrated air compressor according to a first embodiment of the present invention, and FIGS. 5 and 6 are an inverter-integrated inverter according to the first embodiment of the present invention. 7 is a perspective view showing a PCB board and an IGBT of an inverter-integrated air compressor according to a first embodiment of the present invention, and FIG. 8 is an inverter-integrated inverter according to a first embodiment of the present invention. It is a top plan view showing a state in which the upper cover of the air compressor is removed.

As shown, the inverter integrated air compressor according to the first embodiment of the present invention is largely a motor housing 100, a stator 200, a rotor 300, an impeller 400, an impeller housing 410, the first It may be configured to include an air cooling unit 600 , a second air cooling unit 700 , a return pipe 800 , and an inverter 900 . In addition, the inverter integrated air compressor according to the present invention may further include a pair of airfoil journal bearings 510 and 520 , a thrust runner 311 , and a pair of airfoil thrust bearings 530 and 540 .

The motor housing 100 is a part that forms the outer shape of the air compressor, and may include a body and a pair of bearing mounting parts coupled to both ends of the body. The body of the motor housing 100 has an empty interior and may be formed in a substantially cylindrical shape with both ends in the longitudinal direction open, a front bearing mounting unit 110 is coupled to one end of the body, and a rear bearing mounting unit 120 is coupled to the other end of the body. can be combined. Here, the front side is the inlet 411 side of the impeller housing 410, which is the side in which air is introduced from the outside, which is the right side in the longitudinal direction in the drawing, and the rear side is the first air cooling unit 600 which is the left side in the longitudinal direction in the drawing. side can be In addition, the front bearing mounting part 110 and the rear bearing mounting part 120 may be formed in the form of a cover covering and blocking the open end of the body, and a hole passing through both surfaces may be formed in the center, respectively. Thus, the front airfoil journal bearing 510 is inserted and mounted in the hole of the front bearing mounting unit 110 , and the rear airfoil journal bearing 520 is inserted and mounted in the hole of the rear bearing mounting unit 120 . can In addition, a through hole 111 penetrating both surfaces may be formed in the front bearing mounting unit 110 , and the through hole 111 is located radially outward from the hole in which the front air foil journal bearing 510 is mounted. Rather than the outer diameter of the impeller 400, it may be located outside or inside the radial direction. In addition, a through hole 121 penetrating both surfaces may be formed in the rear bearing mounting unit 120 , and the through hole 121 may be located radially outward or inward than the outer diameter of the thrust runner 311 . .

The stator 200 may be provided inside the motor housing 100 , and the stator 200 may be fixed in contact with an inner circumferential surface of the motor housing 100 . In addition, the stator 200 may be disposed such that a coil is wound around a core so that the end turns of the coil face the front side and the rear side. In addition, the stator 200 may be formed in a form in which the central portion is perforated through both surfaces. In addition, the stator 200 has a coil wound on the teeth of the core, and the teeth on which the coil is wound are arranged to be spaced apart in the circumferential direction to form a flow path through which air can flow between the teeth.

The rotor 300 is disposed in a form inserted through the central portion of the stator 200 , and the rotor 300 may be disposed to be spaced apart from the inside of the stator 200 . And the rotor 300 may be configured to include a rotation shaft 310 and a magnet 320, the magnet 320 may be disposed at a position between both sides in the axial direction of the rotation shaft 310. In addition, as an example, the rotation shaft 310 may be coupled to a concave groove formed on an outer circumferential surface and a magnet 320 inserted into the groove. In addition, in the axial direction of the rotation shaft 310, one side is inserted into the inner side of the front airfoil journal bearing 510 and supported so as to be rotatable, and the other side in the axial direction is inserted into the inner side of the rear airfoil journal bearing 520, It may be rotatably supported. Thus, the rotor 300 can be radially supported by the two airfoil journal bearings.

The impeller housing 410 is coupled to the front side, which is one side in the longitudinal direction of the motor housing 100 , and the impeller 400 may be disposed in the inner space formed by the coupling of the impeller housing 410 and the motor housing 100 . . And the impeller housing 410 may be formed with an inlet 411 and a discharge port 412 communicating with the inside, and an inlet 411 through which external air is introduced is formed on the front side, and is radially spaced apart from the inlet 411. A discharge port 412 through which the pressurized air is discharged may be formed at the designated position.

The impeller 400 is provided inside the impeller housing 410 , and the impeller 400 may be coupled to one end of the rotation shaft 310 of the rotor 300 . Thus, when the rotor 300 is rotated, the impeller 400 is rotated together, and external air is sucked through the inlet 411 of the impeller housing 410 by the rotation of the impeller 400, and the pressure is increased through the impeller 400. Afterward, it may be pressure-feed to a predetermined position through the discharge port 412 . In addition, various seal structures such as sawtooth shapes may be formed in the radial outer side of the impeller 400 and the front bearing mounting portion 110 at a position corresponding thereto, and the radial outer side of the impeller 400 by the above-described seal structure. The flow of air through the gap between the end and the front bearing mounting part 110 may be restricted. However, some air may be introduced into the motor housing 100 through a gap between the seal structure of the front bearing mounting part 110 at the radially outer end of the impeller 400 on the discharge side.

The thrust runner 311 is positioned at the other end of the rotation shaft 310 in the longitudinal direction, and the thrust runner 311 may be integrally formed with the rotation shaft 310 . In addition, the thrust runner 311 may be formed in a disk shape, and may be disposed on the left side of the rear bearing mounting unit 120 . In addition, a front air foil thrust bearing 530 may be interposed between the rear bearing mounting unit 120 and the thrust runner 311 , and the front air foil thrust bearing 530 may be formed by the rear bearing mounting unit 120 . It can be installed on the left side of the

The first air cooling unit 600 may be coupled to the rear side, which is the other side in the longitudinal direction of the motor housing 100 , and the first air cooling unit 600 is a first cooling air flow path through which air may flow ( It may be formed in the form of a chamber in which 610 is formed, and an inlet 611 and an outlet 612 communicating with the first cooling air flow path 610 may be formed. In addition, the first air cooling unit 600 may be coupled to the rear bearing mounting unit 120 , and the thrust runner 311 may be disposed between the first air cooling unit 600 and the rear bearing mounting unit 120 . can In this case, the space between the first air cooling unit 600 and the rear bearing mounting unit 120 may be formed to be larger than the thickness and outer diameter of the thrust runner 311 so that the thrust runner 311 can rotate smoothly. In addition, a seating groove in which the thrust runner 311 is seated may be concavely formed in the rear bearing mounting part 120 , and a through hole 121 may be connected to the seating groove, and the through hole 121 may be formed in the front side air. It may be disposed radially outward than the foil thrust bearing 530 . In addition, a rear air foil thrust bearing 540 may be interposed between the thrust runner 311 and the first air cooling unit 600 , and the rear air foil thrust bearing 540 may be connected to the first air cooling unit ( 600) can be mounted on the right side. In addition, the inlet 611 formed in the first air cooling unit 600 may be formed at a position corresponding to the through hole 121 , and may be located radially outward than the rear air foil thrust bearing 540 . have. In addition, in the rear bearing mounting portion 120, the front airfoil thrust bearing 530 and the rear airfoil journal bearing 520 are adjacent in the interior of the motor housing 100. Air is passed in a diagonal direction toward the adjacent corner portion. A through hole 122 that can be formed may be further formed. In addition, the outlet 612 may be formed at various positions, and may be located on the upper side of the first air cooling unit 600 as shown as an example. In addition, the first air cooling unit 600 may have a plurality of heat dissipation fins 613 protruding from the inner surface forming the first cooling air flow path 610 to improve heat exchange efficiency, and the shape of the heat dissipation fins 613 and The arrangement may be formed in various ways. In addition, the first air cooling unit 600 may radiate heat to the outside by exposing the left side, which is a part of the surface, to the outside, and although not shown, heat dissipation fins may be formed on the surface that radiates heat to the outside. Also, in the first air cooling unit 600 , an opening 620 communicating with the first cooling air flow path 610 may be formed in a central portion corresponding to the rotation shaft 310 on a surface facing the rotation shaft 310 . In addition, heat dissipation fins may be formed on the inner surface of the motor housing 100 , the front bearing mounting part 110 , and the rear bearing mounting part 120 to improve heat exchange efficiency as shown.

The second air cooling unit 700 may include a cooling water flow path 710 and a second cooling air flow path 720 . The cooling water flow path 710 may be formed to pass through the motor housing 100 , and for example, the cooling water flow path 710 may have a zigzag shape or a corrugated shape while going in the circumferential direction of the cylindrical body constituting the motor housing 100 . It may be formed in various shapes such as In addition, the cooling water inlet and outlet connected to the cooling water flow path 710 may be formed in the motor housing 100 so that the cooling water may circulate along the cooling water flow path 710 , and the cooling water inlet and outlet are connected to an external coolant pump and coolant tank. can be connected In addition, the second cooling air flow path 720 may be formed in a position adjacent to the cooling water flow path 710 , and the second cooling air flow path 720 may be formed to pass through the motor housing 100 . In addition, the second cooling air flow path 720 may have one end connected to the outlet 612 of the first cooling air flow path 610 and the other end formed on the outer surface of the motor housing 100 .

The return tube 800 may be formed of various types of tubes, such as a pipe, a hose, a flexible tube, and the like, and the return tube 800 may be disposed outside the motor housing 100 and the impeller housing 410 . And the return pipe 800 has one end connected to the other end of the second cooling air flow path 720 , and the return pipe 800 has the other end connected to the inlet 411 , which is the external air inlet side of the impeller housing 410 . .

Thus, when the impeller 400 is rotated, some air from the air discharge side of the impeller 400 passes through the gap between the impeller 400 and the seal structure formed in the front bearing mounting part 110 of the motor housing 100. Part of the branched air may be introduced into the motor housing 100 through the front air foil journal bearing 510 , and the remaining air may be introduced into the motor housing 100 through the through hole 111 . And the air introduced into the motor housing 100 is branched after passing through the flow path between the stator 200 and the rotor 300 and between the teeth of the stator 200, and some air is in the rear air foil journal After passing through the bearing 520 and the front air foil thrust bearing 530 in sequence, it flows into the space between the rear bearing mounting unit 120 and the first air cooling unit 600 , and some air passes through the diagonally formed through After passing through the front air foil thrust bearing 530 sequentially through the ball 122 , it is introduced into the space between the rear bearing mounting unit 120 and the first air cooling unit 600 , and the remaining air passes through the through hole 121 . ) may be introduced into the space between the rear bearing mounting part 120 and the first air cooling part 600 . After that, the air is branched and some air passes through the rear air foil thrust bearing 540 and flows into the first cooling air passage 610 through the opening 620 of the first air cooling unit 600, and the remaining air is It may be introduced into the first cooling air flow path 610 through the inlet 611 of the first air cooling unit 600 . The air introduced into the first cooling air flow path 610 flows in the first cooling air flow path 610 and exchanges heat with the heat dissipation fins 613 to be cooled first, and then discharged through the outlet 612 to cool the second air. It is introduced into the second cooling air passage 720 of the unit 700 . Here, the air flow in the first cooling air flow path 610 of the first air cooling unit 600 may have an irregular flow or a rotational flow along the circumferential direction. A flow may be formed. The air introduced into the second air cooling unit 700 is heat exchanged with the cooling water flowing along the cooling water flow path 710 located in the vicinity while following the second cooling air flow path 720 to be cooled secondly and then the return pipe 800 through the inlet 411 of the impeller housing 410 may be introduced. At this time, while the air passing through the gap between the impeller 400 and the front bearing mounting part 110 of the motor housing 100 flows, the front air foil journal bearing 510 , the stator 200 , and the rotor 300 ) , it is possible to uniformly cool the rear airfoil journal bearing 520 , the front airfoil thrust bearing 530 , and the rear airfoil thrust bearing 540 . And the air heated by cooling the above components is cooled primarily by air cooling through heat radiation from the first air cooling unit 600 to the outside, and secondarily cooled by water cooling by cooling water in the second air cooling unit 700 . Afterwards, it is returned to the inlet 411 of the impeller housing 410 . Accordingly, an increase in the temperature of the cooling air can be prevented, and the components can be cooled more efficiently.

In addition, a through hole 123 penetrating both surfaces may be additionally formed in the rear bearing mounting unit 120 , and the through hole 123 may be formed not to communicate with the space in which the thrust runner 311 is disposed. have. In addition, an inlet 614 connecting the through hole 123 and the first cooling air flow path 610 may be additionally formed in the first air cooling unit 600 . Accordingly, a portion of the air inside the motor housing 100 may be directly introduced into the first air cooling unit 600 through the through hole 123 without passing through the air foil thrust bearings 530 and 540 .

The inverter 900 may largely include a PCB substrate 910 and an IGBT 920 , and may further include electronic devices 940 . In addition, a concave accommodation space is provided on the outer peripheral surface of the motor housing 100 , and the inverter 900 is inserted into the accommodation space, and the inverter 900 may be coupled and fixed to the motor housing 100 . In addition, the PCB substrate 910 and the IGBT 920 may be disposed to form a 90 degree angle to be coupled and electrically connected to each other. Thus, the PCB substrate 910 may be disposed on the front side of the motor housing 100 in the width direction, and the IGBT 920 may be disposed on the top side of the motor housing 100 in the height direction. In addition, electronic devices 940 such as capacitors and current sensors may be disposed on the upper surface side on which the IGBT 920 is disposed, and the electronic devices 940 are electrically connected to the main connector and the IGBT 920 to which power is input from the outside. can be connected In addition, a cover is coupled to the portion in which the inverter 900 is accommodated of the motor housing 100 so that the inverter 900 can be sealed, the front cover 960 is coupled to the front side, and the upper cover 950 is coupled to the top side. can

Accordingly, in the inverter integrated air compressor of the present invention, the cooling effect of the stator and rotor of the motor, the airfoil journal bearing and the airfoil thrust bearing is improved, and the cooling air cooled inside the motor is not discharged to the outside of the air compressor. , outside air may not be polluted, and there is no need for a separate air exhaust structure in the facility or installation space where the air compressor is installed. In addition, an air compressor having an inverter integrated therein can be manufactured in a compact size, and cooling of the inverter can be facilitated.

In addition, the inverter integrated air compressor of the present invention may further include a cooling plate 930 , and the cooling plate 930 may be provided on the inverter 900 side to cool the inverter 900 . Here, a flow path through which the cooling water can flow is formed inside the cooling plate 930 , and the cooling plate 930 is connected to the cooling water flow path 710 formed in the motor housing 100 so that the cooling water can flow. And the IGBT 920 is interposed between the motor housing 100 and the cooling plate 930, and one surface of the IGBT 920 is in contact with the outer peripheral surface of the motor housing 100 and the other surface is in contact with the cooling plate 930. have. Here, since heat is generated from both sides of the IGBT 920, both sides of the IGBT 920 can be uniformly cooled by the cooling water flow path 710 and the cooling plate 930 formed in the motor housing 100, so that the IGBT ( 920) can be effectively cooled. In addition, among the coolant flow paths 710 formed in the motor housing 100 , some coolant flow paths close to the IGBT 920 are connected in parallel with the cooling plate 930 , but a blocked part is formed in the middle, so that the coolant flows toward the cooling plate 930 . While flowing smoothly, it is possible to easily cool the lower side of the IGBT (920).

<Example 2>

9 is a plan cross-sectional view showing an inverter-integrated air compressor according to a second embodiment of the present invention.

As shown, the inverter-integrated air compressor according to the second embodiment of the present invention does not have the second air cooling unit 700 in the first embodiment, and directs the cooling air discharged from the first air cooling unit 600 . It is configured to return toward the inlet 411 of the impeller housing 410 through the return passage 312 formed on the rotation shaft 310 of the rotor 300 . That is, in the inverter-integrated air compressor according to the second embodiment of the present invention, the outlet 612a of the air cooling unit 600a penetrates inside and outside the central portion of the side facing the rotation shaft 310 of the rotor 300 . The rotation shaft 310 of the rotor 300 has a return flow path 312 penetrating both sides in the axial direction, so that one end of the return flow path 312 is an outlet 612a of the air cooling unit 600a. and the other end may be connected to the air inlet 411 of the impeller housing 410 . In addition, a cooling water flow path 710 through which cooling water for cooling the motor flows may be formed in the motor housing 100 .

<Example 3>

10 is a plan cross-sectional view showing an inverter-integrated air compressor according to a third embodiment of the present invention.

As shown, the air compressor according to the third embodiment of the present invention has a configuration in which one more impeller is added in the first embodiment described above. That is, in the inverter-integrated air compressor according to the third embodiment of the present invention, the first impeller housing 410a and the first impeller 400a are disposed on one side of the motor housing 100, and the first impeller 400a is a rotating shaft ( 310) may be coupled to one end. In addition, the second impeller housing 410b and the second impeller 400b may be disposed on the other side of the motor housing 100 , and the second impeller 400b may be coupled to the other end of the rotation shaft 310 . Here, the rotation shaft 310 may pass through the first air cooling unit 600 . Thus, the first air cooling unit 600 may be disposed between the thrust runner 311 and the second impeller 400b.

Here, in the air compressor according to the third embodiment of the present invention, the air that is compressed and discharged from the first impeller 400a side is sent to the inlet side of the second impeller 400b, and the air is secondarily compressed and discharged to a desired place. It can be applied to a two-stage impeller type air compressor configured to be sent to Alternatively, air is compressed and discharged from the side of the first impeller 400a and sent to a fuel cell stack for a vehicle, and the remaining compressed air used in the fuel cell stack is sent to the inlet side of the second impeller 400b and sent to the second impeller 400b. may be configured to rotate. Thus, the first impeller 400a is used as energy required to compress air, thereby improving the efficiency of the air compressor.

The present invention is not limited to the above-described embodiments, and the scope of application is varied, and anyone with ordinary knowledge in the field to which the present invention pertains without departing from the gist of the present invention as claimed in the claims It goes without saying that various modifications are possible.

100: motor housing
110: front bearing mounting part 111: through hole
120: rear bearing mounting portion 121: through hole
122: through hole 123: through hole
200: stator
300: rotor 310: rotation shaft
311: thrust runner 312: return euro
320: magnet
400: impeller 410: impeller housing
411: inlet 412: outlet
400a: first impeller 410a: first impeller housing
400b: second impeller 410b: second impeller housing
510: front side airfoil journal bearing
520: rear airfoil journal bearing
530: front air foil thrust bearing
540: rear air foil thrust bearing
600: first air cooling unit 610: first cooling air flow path
611: entrance 612: exit
613: heat dissipation fin 614: inlet
620: opening
700: second air cooling unit
710: cooling water flow path 720: second cooling air flow path
800: return tube
900: inverter 910: PCB board
920: IGBT 930: cooling plate
940: electronic device 950: upper cover
960: front cover

Claims (12)

a motor housing having a stator and a rotor therein, the rotor being rotatably coupled;
an impeller housing coupled to one side of the motor housing, an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing;
an impeller provided inside the impeller housing and coupled to one end of the rotor;
First air coupled to the other side of the motor housing, a first cooling air flow path is formed therein, an inlet and an outlet communicating with the first cooling air flow path are formed, the inlet communicating with the inside of the motor housing cooling unit;
a cooling water passage passing through the motor housing and a second cooling air passage passing through the motor housing adjacent to the cooling water passage, wherein one end of the second cooling air passage is connected to an outlet of the first cooling air passage 2 air cooling unit;
a return pipe having one end connected to the other end of the second cooling air flow path and the other end connected to the air inlet of the impeller housing; and
an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing;
Inverter-integrated air compressor comprising a.
According to claim 1,
In the inverter, the PCB substrate and the IGBT are arranged parallel to the central axis direction of the motor housing, and the PCB substrate and the IGBT are arranged at a specific angle.
According to claim 1,
The cooling water flow path is an inverter-integrated air compressor, characterized in that formed in a corrugate shape along a circumferential direction of the motor housing.
According to claim 1,
It is provided in the inverter and further comprises a cooling plate connected to the cooling water flow path,
The IGBT is interposed between the motor housing and the cooling plate, and one surface of the IGBT is in contact with the outer peripheral surface of the motor housing and the other surface is in contact with the cooling plate.
According to claim 1,
Air introduced into the motor housing through a gap between the impeller and the motor housing on the air discharge side of the impeller is heated by heat exchange with the stator and rotor while passing through the motor housing, and then to the first air cooling unit The air is firstly cooled by being introduced and radiating heat to the outside, and then it passes through the second air cooling unit and is secondarily cooled by the cooling water, and then the air is introduced into the air inlet side of the impeller housing through the return pipe. Inverter-integrated air compressor.
According to claim 1,
The first air cooling unit,
Inverter-integrated air compressor, characterized in that a plurality of heat dissipation fins protrude from an inner surface forming the first cooling air flow path.
According to claim 1,
a pair of airfoil journal bearings coupled to bearing mounting portions formed on both sides of the motor housing, spaced apart from both sides of the rotor, and supporting a radial load so that the rotor is rotatable;
a thrust runner coupled to the other end of the rotor and disposed between the other bearing mounting part of the motor housing and the first air cooling part; and
a pair of air foil thrust bearings interposed between a bearing mounting portion adjacent to the thrust runner and the thrust runner and between the thrust runner and the first air cooling portion to support an axial load such that the thrust runner is rotatable;
Inverter-integrated air compressor comprising a further.
8. The method of claim 7,
Air passing through the gap between the impeller and the motor housing on the air discharge side of the impeller is an airfoil journal bearing disposed on one side, an airfoil journal bearing disposed on the other side, between the stator and the rotor, and the pair of airfoils Inverter-integrated air compressor, characterized in that after passing through one or more air foil thrust bearings among the thrust bearings in turn, the air is introduced into the first air cooling unit.
8. The method of claim 7,
Through-holes penetrating both surfaces are formed in the bearing mounting portions on both sides of the motor housing, and air passing through the gap between the impeller and the motor housing on the air discharge side of the impeller is an air foil journal bearing disposed on one side and a through hole on one side is branched so as to pass through, and the air that has passed between the stator and the rotor is branched so as to pass through the air foil journal bearing disposed on the other side and the through hole of the other side.
10. The method according to any one of claims 7 to 9,
The first air cooling unit,
An opening penetrating inside and outside is formed in a central portion of a side facing the thrust runner, and the opening communicates with an air foil thrust bearing side disposed on the other side of the thrust runner.
a motor housing having a stator and a rotor therein, rotatably coupled to the rotor, and having a coolant passage passing therethrough;
an impeller housing coupled to one side of the motor housing, an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing;
an impeller provided inside the impeller housing and coupled to one end of the rotor;
an air cooling unit coupled to the other side of the motor housing, having a cooling air flow path formed therein, an inlet and an outlet communicating with the cooling air flow path, the inlet communicating with the inside of the motor housing; and
an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing;
is made, including
The outlet of the air cooling unit is formed through the inside and the outside in the central portion of the side facing the rotation shaft of the rotor,
Inverter-integrated air, characterized in that the rotation shaft of the rotor has a return flow passage penetrating both sides in the axial direction, and one end of the return flow passage is connected to the outlet of the air cooling unit and the other end is connected to the air inlet of the impeller housing. compressor.
a motor housing having a stator and a rotor therein, rotatably coupled to the rotor, and having a coolant passage passing therethrough;
a first impeller housing coupled to one side of the motor housing, an air inlet and an air outlet communicating with the inside, and communicating with the inside of the motor housing;
a first impeller provided inside the impeller housing and coupled to one end of the rotor;
First air coupled to the other side of the motor housing, a first cooling air flow path is formed therein, an inlet and an outlet communicating with the first cooling air flow path are formed, the inlet communicating with the inside of the motor housing cooling unit;
a cooling water passage passing through the motor housing and a second cooling air passage passing through the motor housing adjacent to the cooling water passage, wherein one end of the second cooling air passage is connected to an outlet of the first cooling air passage 2 air cooling unit;
a return pipe having one end connected to the other end of the second cooling air flow path and the other end connected to the air inlet of the impeller housing;
a second impeller housing coupled to the outside of the first air cooling unit on the other side of the motor housing and having an air inlet and an air outlet communicating with the inside;
a second impeller provided inside the impeller housing and coupled to the other end of the rotor; and
an inverter including a PCB substrate and an IGBT coupled to the PCB substrate, the inverter being disposed on an outer peripheral surface of the motor housing and coupled to the motor housing;
Inverter-integrated air compressor comprising a.

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