KR102623355B1 - A motor with bearing cooling structure - Google Patents

Abstract

A motor equipped with a bearing cooling structure according to an embodiment of the present invention includes a rotor having a rotor core fixedly coupled to the outer peripheral surface of a shaft having a load side and a half-load side end; a stator disposed to surround the outer peripheral surface of the rotor and having a coil supplied with power wound thereon to form a rotating magnetic field between the stator and the rotor; A housing having a receiving space therein for accommodating the rotor and the stator; a front bracket coupled to the front of the housing and having a first bearing disposed in a hollow formed at the center so that the shaft can be fastened; A rear bracket coupled to the rear of the housing and having a second bearing disposed in a hollow formed in the center so that the shaft can be fastened, wherein the receiving space inside the housing is closed by the front bracket and the rear bracket, A bearing cooling passage is formed in at least one of the front bracket and the rear bracket to cool the first bearing or the second bearing by introducing external air.

Description

Motor with bearing cooling structure {A MOTOR WITH BEARING COOLING STRUCTURE}

The present invention relates to motors, and specifically to motors equipped with a bearing cooling structure.

In general, railway vehicles adopt induction motors through inverter control, which provides many advantages in use. This inverter control is a method of driving multiple induction motors with one inverter from the viewpoint of making the device smaller, lighter, and lower cost. This is mainstream.

Recently, synchronous motors using permanent magnets due to improved performance have been attracting attention in industrial, electric vehicle, and all other fields, and by taking advantage of the characteristics of small size, light weight, and high efficiency, they are becoming the leading high-performance motors, replacing induction motors.

Traction motors using such permanent magnets have the advantages of higher efficiency, improved maintainability, and miniaturization and lighter weight compared to existing induction motors.

In particular, in the case of electric motors for railway vehicles, a totally enclosed type motor in which the motor housing surrounds the entire motor to prevent air around the motor from flowing into and circulating inside the motor may be applied.

This type of fully enclosed motor has the advantage of preventing contamination inside the motor housing due to external foreign substances, but has the problem that it is impossible to cool the inside of the motor through the inflow and circulation of external air.

In order to overcome this problem, a fully enclosed external motor has been proposed that is equipped with a separate cooling fan in a fully enclosed structure and can improve cooling performance by flowing the external air introduced by the cooling fan through a passage formed on the outer shell of the motor. .

Although this fully enclosed external motor can effectively dissipate heat generated from the coils inside the motor, there is a problem in that it cannot effectively cool the bearings provided inside, so a cooling structure is required to overcome this problem.

Meanwhile, the following prior art document shows that by forming a cooling water path for water cooling the high temperature heat generated when driving the drive motor in the stator accommodated inside the motor housing instead of forming it in the motor housing, not only more efficient cooling is achieved, but also the cooling water required for cooling is achieved. It only discloses information about a cooling device for an electric motor that reduces space, but does not disclose the technical gist of the present invention.

Republic of Korea Patent Publication 10-0907937

A motor equipped with a bearing cooling structure according to an embodiment of the present invention aims to solve the following problems in order to solve the above-mentioned problems.

The aim is to provide a motor with a structure that prevents foreign matter from entering the motor, effectively cools the inside of the motor, and further efficiently cools bearings coupled to the load-side or anti-load-side shaft.

The problems to be solved by the present invention are not limited to those mentioned above, and other problems not mentioned can be clearly understood by those skilled in the art from the description below.

A motor equipped with a bearing cooling structure according to an embodiment of the present invention includes a rotor having a rotor core fixedly coupled to the outer peripheral surface of a shaft having a load side and a half-load side end; a stator disposed to surround the outer peripheral surface of the rotor and having a coil supplied with power wound thereon to form a rotating magnetic field between the stator and the rotor; A housing having a receiving space therein for accommodating the rotor and the stator; a front bracket coupled to the front of the housing and having a first bearing disposed in a hollow formed at the center so that the shaft can be fastened; and a rear bracket coupled to the rear of the housing and having a second bearing disposed in a hollow formed in the center so that the shaft can be fastened, wherein the receiving space inside the housing is closed by the front bracket and the rear bracket. , a bearing cooling passage is formed in at least one of the front bracket or the rear bracket to cool the first bearing or the second bearing by introducing outside air, and the front bracket is formed to be concave in the center toward the housing. landing area; and at least one open area radially formed in a peripheral area outside the seating area, wherein a first hollow is formed on the bottom surface of the seating area, and the first bearing includes an inner peripheral surface of the first hollow and It is disposed between the outer peripheral surfaces of the shaft.

It is preferable that the stator and the housing are formed integrally.

The front bracket includes a heat sink that closes the open area; at least one inlet hole disposed between the open area and the seating area; and a cover closing the seating area. It is preferable to further include a cover.

delete

It further includes a load-side fan seated in the seating area and rotating based on the rotation of the shaft, wherein the load-side fan includes an inner wall, an outer wall formed to be spaced apart from the inner wall, and an inner wall formed in a ring shape between the inner wall and the outer wall. It is preferable to include a flow path and at least one partition wall disposed in the internal flow path.

A guide passage is formed inside the front bracket to guide external air introduced from the inlet hole to the first bearing, the guide passage communicates with the internal passage of the load side fan, and the bearing cooling passage is the guide passage. And it is preferable that it is the internal flow path.

When the load-side fan rotates based on the rotation of the shaft, it is preferable that the outside air flowing into the inlet hole is discharged through the guide passage and the internal passage through the discharge hole formed in the cover.

It is preferable to further include a half-load side fan accommodated inside the rear bracket and rotating based on rotation of the shaft.

A motor with a bearing cooling structure according to an embodiment of the present invention has a load-side fan inside the front bracket that rotates together based on the rotation of the shaft, and circulates external air through a flow path formed in the front bracket and the load-side fan. The effect of effectively cooling the bearings placed in can be expected.

The effects of the present invention are not limited to those mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the description below.

1 and 2 are perspective views of a motor equipped with a bearing cooling structure according to an embodiment of the present invention.
3 and 4 are exploded perspective views of a motor equipped with a bearing cooling structure according to an embodiment of the present invention.
Figure 5 is an exploded perspective view for explaining the assembly and arrangement position of the front bracket and load-side fan among the configuration of the motor with a bearing cooling structure according to an embodiment of the present invention.
FIG. 6 is a perspective view of a motor with a bearing cooling structure showing FIG. 1 from a different angle.
Figures 7 and 8 are cross-sectional views of area AA of Figure 1.

Preferred embodiments according to the present invention will be described in detail with reference to the attached drawings, but identical or similar components will be assigned the same reference numbers regardless of reference numerals, and duplicate descriptions thereof will be omitted.

Additionally, when describing the present invention, if it is determined that a detailed description of related known technologies may obscure the gist of the present invention, the detailed description will be omitted. In addition, it should be noted that the attached drawings are only intended to facilitate easy understanding of the spirit of the present invention, and should not be construed as limiting the spirit of the present invention by the attached drawings.

Hereinafter, a motor equipped with a bearing cooling structure according to an embodiment of the present invention will be described with reference to the attached drawings.

A motor equipped with a bearing cooling structure according to an embodiment of the present invention includes a rotor 100, a stator 200, a housing 300, a front bracket 400, and a rear bracket as shown in FIGS. 1 to 8. It is configured to include (500), a half-load side fan (600), and a load side fan (700).

The rotor 100 is composed of a shaft 10 and a rotor iron core, and the shaft 10 can be divided into a load side connected to the load and a semi-load side that is opposite to the load side.

This shaft 10 performs the function of transmitting the rotational force generated by driving the motor to a load coupled to the load side of the shaft 10, for example, a wheel of a railroad vehicle.

The rotor core is fixedly coupled to the outer peripheral surface of the shaft 10. The rotor core rotates in a rotating magnetic field formed between the stator 200, which will be described later, and the shaft 10 is moved together by the rotation of the rotor core. It rotates.

In this rotor iron core, a plurality of internal passages formed radially around the rotation axis of the shaft 10 may be disposed, and a plurality of magnetic materials, that is, permanent magnets, for forming a magnetic field may be disposed.

In particular, the air flowing through the internal flow path formed in the rotor iron core can cool the rotor by performing heat exchange with a large amount of heat generated in the rotor.

The stator 200 is arranged to surround the outer circumferential surface of the rotor 100, and specifically, its inner circumferential surface is spaced apart from the outer circumferential surface of the rotor 100 at a slight distance, and has a structure inside for winding a coil. A winding portion is formed.

As described above, when current is applied to the coil wound on the winding part of the stator 200, a rotating magnetic field is formed by the coil and the magnetic material disposed inside the rotor 100, and through this process, the rotor 100 It rotates.

The housing 300 is composed of a columnar structure with a receiving space 310 formed inside to accommodate the rotor 100 and the stator 200, and has at least one external cooling passage 320 formed along the longitudinal direction on the outer peripheral surface. ) can be formed.

In particular, the external cooling passage 320 is a path through which external air flows in from the outside by the half-load side fan 600, which will be described later, through which the rotor 100 and the stator 200 can be cooled, as shown in Figures 1 to 1. As shown in FIG. 4, it is preferable that the four external cooling passages 320 are formed to be spaced apart by 90 degrees.

The front bracket 400 is coupled to the front of the housing 300 to close the front of the housing 300, and the first cooling passage 410 is formed in the area corresponding to the external cooling passage 320 of the housing 300. is formed, and one side of the first cooling passage 410 is configured to communicate with one side of the external cooling passage 320, so that the external air flowing along the external cooling passage 320 is discharged to the outside.

This front bracket 400 includes not only the first cooling passage 410 described above, but also a seating area 420, a first hollow 430, a first bearing 440, and an open area 450 as shown in FIG. 5. , It is configured to include a heat sink 460, an inlet hole 470, and a cover 480.

The seating area 420 is a concave area formed at the center of the front bracket 400 in the direction of the housing 300, and a load-side fan 700, which will be described later, is disposed.

The first hollow 430 is formed on the bottom surface of the seating area 420 for inserting the shaft 10, and the first bearing 440 is formed between the first hollow 430 and the outer peripheral surface of the shaft 10. It is a configuration placed in .

The open area 450 is formed radially in the peripheral area outside the seating area 420, and the heat sink 460 is coupled to the open area 450, thereby creating the receiving space 310 inside the housing 300. is closed.

Meanwhile, a first circulation member 330 fixedly coupled to the shaft 10 may be disposed in the front receiving space 310a of the receiving space 310, and the first circulating member 330 may be disposed based on the rotation of the shaft 10. When (330) rotates, the hot air within the front receiving space (310a) moves to the inner peripheral surface of the front bracket (400), and at this time, heat exchange with the outside occurs by the heat sink 460 and the inside of the front receiving space (310a) can be cooled.

In addition, in order to increase the heat exchange efficiency by the heat sink 460, it is desirable to expand the heat exchange area of the heat sink 460, and for this purpose, the heat sink 460 is preferably formed with a plurality of heat dissipation fins as shown in FIG. 5.

In addition, it is possible to form a heat dissipation fin on the front of the front bracket 400, but in order to ensure ease of manufacture of the front bracket 400 and minimize costs due to defects, a heat dissipation plate 460 is formed separately as in the present invention. It is preferably configured to be coupled to the open area 450 of the front bracket 400.

The inlet hole 470 is formed between the above-described open area 450 and the seating area 420 and is configured to introduce external air. The detailed function of the inlet hole 470 will be described later.

In addition, the cover 480 functions to close the seating area 420, and a second hollow 482 is formed in this cover to expose the load end of the shaft 10 to the outside, and further the inlet hole 470 ) A discharge hole 481 is formed to discharge the external air introduced by the.

Meanwhile, the load-side fan 700, which is seated in the seating area 420 of the front bracket 400, is configured to rotate based on the rotation of the shaft 10, and as shown in FIG. 5, the fan 700 on the load side is centered with the shaft 10. A third hollow 750 for coupling is formed, and an inner wall 710 and an outer wall 720 are formed spaced apart from the inner wall 710, and an inner wall is formed in a ring shape between the inner wall 710 and the outer wall 720. A flow path 730 is formed, and a plurality of partition walls 740 serving as wings are formed in the internal flow path 730 and spaced apart at preset intervals.

When explaining the cooling method of the first bearing 440 by combining the above-described front bracket 400 and the load side fan 700 with reference to FIGS. 7 and 8, the inside of the front bracket 400 has a guide passage ( 490) is formed, and the guide passage 490 is formed to guide the external air flowing in from the inlet hole 470 to the first bearing 440. The guide passage 490 is particularly an internal passage of the load side fan 700. It is configured to communicate with (730).

When the shaft 10 rotates, the load-side fan 700 rotates together, and at this time, the outside air flows through the guide passage 490 and the internal passage 730 through the inlet hole 470, as shown in FIG. 8. It is discharged through the discharge hole 481 formed in the rear cover 480, and in this process, heat exchange occurs with the first bearing 440, thereby allowing the first bearing 440 to be cooled.

In addition, the guide passage 490 and the internal passage 730 are formed so as not to communicate with the first receiving space 310a, and thus prevent the external air flowing in through the inlet hole 470 from flowing into the receiving space 310. do.

The rear bracket 500 is coupled to the rear of the housing 300, and a second cooling passage 510 is formed on one side of which communicates with the other side of the external cooling passage 320 of the housing 300, and the rear is used to introduce external air. This is a configuration in which an inlet 520 is formed.

As shown in FIGS. 7 and 8, the rear bracket 500 is configured on one side to close the receiving space 310 inside the housing 300, and has a hollow space through which the shaft 10 can pass. , a half-load side fan 600 that rotates based on the rotation of the half-load side end of the shaft 10 and the shaft 10 is disposed between one side and the other side, and the inlet 520 described above is disposed at the rear.

By combining the rear bracket 500, the rear of the housing 300 is sealed by the front of the rear bracket 500, and since outside air does not flow into the housing 300, foreign substances do not flow into the housing 300. can be prevented.

In particular, when the shaft 10 rotates, the half-load side fan 600 rotates together, and at this time, the external air introduced from the inlet 520 flows into the second cooling passage 510 and the external cooling passage ( 320) and is configured to be discharged to the outside via the first cooling passage 410.

Meanwhile, a second bearing 530 for supporting the shaft 10 is disposed in the hollow formed in the front of the rear bracket 500, and a circulation passage 540 is formed to pass through an area adjacent to the second bearing 530 on the front. By forming, some of the external air introduced through the inlet 520 by the half-load side fan 600 can be configured to pass through the circulation passage 540, through which the second bearing 530 can be easily cooled. It becomes possible.

Meanwhile, a second circulation member 340 fixedly coupled to the shaft 10 may be disposed in the rear receiving space 310b of the receiving space 310, and based on the rotation of the shaft 10, the second circulating member ( When 340) rotates, the hot air within the rear accommodation space 310b moves towards the front of the rear bracket 500, and at this time, heat exchange occurs with the front of the rear bracket 500, cooling the inside of the rear accommodation space 310b. It becomes possible.

Above, the present invention has been described in detail using preferred embodiments, but the scope of the present invention is not limited to the specific embodiments and should be interpreted in accordance with the appended claims. Additionally, those skilled in the art should understand that many modifications and variations are possible without departing from the scope of the present invention.

10: shaft
100: rotor
200: stator
300: housing
400: Front bracket
500: Rear bracket
600: Half-load side fan
700: Load side fan

Claims (8)

A rotor having a rotor core fixedly coupled to the outer peripheral surface of a shaft having load-side and anti-load-side ends;
a stator disposed to surround the outer peripheral surface of the rotor and having a coil supplied with power wound thereon to form a rotating magnetic field between the stator and the rotor;
A housing having an accommodating space formed therein to accommodate the rotor and the stator;
a front bracket coupled to the front of the housing and having a first bearing disposed in a hollow formed at the center so that the shaft can be fastened; and
a rear bracket coupled to the rear of the housing and having a second bearing disposed in a hollow formed at the center so that the shaft can be fastened;
Including,
The receiving space inside the housing is closed by the front bracket and the rear bracket,
A bearing cooling passage is formed in at least one of the front bracket and the rear bracket to cool the first bearing or the second bearing by introducing external air,
The front bracket is,
A seating area concavely formed in the center toward the housing; and
at least one open area formed radially in a peripheral area outside the seating area;
Including,
A motor having a bearing cooling structure in which a first hollow is formed on the bottom surface of the seating area, and the first bearing is disposed between the inner peripheral surface of the first hollow and the outer peripheral surface of the shaft.
In claim 1,
A motor with a bearing cooling structure in which the stator and the housing are integrally formed.
delete The method of claim 1, wherein the front bracket is:
a heat sink closing the open area;
at least one inlet hole disposed between the open area and the seating area; and
a cover closing the seating area;
A motor having a bearing cooling structure further comprising:
In claim 4,
It further includes a load-side fan seated in the seating area and rotating based on rotation of the shaft,
The load-side fan is a motor having a bearing cooling structure including an inner wall, an outer wall formed to be spaced apart from the inner wall, an inner flow path formed in a ring shape between the inner wall and the outer wall, and at least one partition disposed in the inner flow path. .
In claim 5,
A guide passage is formed inside the front bracket to guide external air introduced from the inlet hole to the first bearing,
The guide passage communicates with the internal passage of the load side fan,
A motor having a bearing cooling structure in which the bearing cooling passage is the guide passage and the internal passage.
In claim 6,
When the load-side fan rotates based on the rotation of the shaft, the external air flowing into the inlet hole is discharged to the discharge hole formed in the cover via the guide passage and the internal passage.
In claim 1,
a half-load side fan accommodated inside the rear bracket and rotating based on rotation of the shaft;
A motor having a bearing cooling structure further comprising:

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