WO2021091157A1

WO2021091157A1 - Rotor structure for improving cooling function of drive motor

Info

Publication number: WO2021091157A1
Application number: PCT/KR2020/014860
Authority: WO
Inventors: 류영현
Original assignee: 송과모터스 주식회사
Priority date: 2019-11-06
Filing date: 2020-10-29
Publication date: 2021-05-14
Also published as: KR102275325B1; CN114616748B; CN114616748A; KR20210054755A

Abstract

The present invention relates to a rotor structure for improving the cooling function of a drive motor, in which a rotating shaft of a rotor for the drive motor is divided into two sections having different outer and inner diameters on the basis of the longitudinal direction thereof, and a rotor core in a section having relatively large outer and inner diameters is installed such that a cooling flow path in an area where a cooling action is largely exhibited is further expanded, and a cooling flow path in an area where the cooling action is exhibited in a relatively small manner is further reduced so as to improve the overall cooling function and efficiency of the rotor, and at the same time, to this end, a cooling fluid in the rotating shaft is able to be supplied and discharged smoothly without stagnation and clogging. The rotor structure for improving the cooling function of the drive motor according to the present invention comprises: a rotating shaft which is hollow and has one end that is closed and the other end that is open in the longitudinal direction thereof, and comprises a first space portion which is adjacent to the closed one end and, at the same time, has an inner space having a relatively large diameter, and a second space portion which has a relatively small diameter and, at the same time, is adjacent to the open other end; and a rotor core which is joined to an outer surface corresponding to the first space portion of the rotating shaft. The rotor structure is composed in a manner such that a leading-in end of a cooling fluid supply pipe, which is led into the inner space of the rotating shaft through the open other end of the rotating shaft, is led into a position beyond the middle of the first space portion.

Description

Rotor structure to improve the cooling function of the drive motor

In the present invention, the rotating shaft of the rotor for a drive motor is divided into two sections with different outer and inner diameters based on the longitudinal direction, and the rotor core is installed in a section with a relatively large outer and inner diameter, thereby exhibiting a large cooling effect. The cooling flow path in the region is expanded and the cooling flow path in the region where the cooling action is exerted relatively small is further reduced to improve the overall cooling function and efficiency of the rotor, and at the same time, supply and discharge of the cooling fluid in the rotating shaft are stagnated and discharged for this purpose. The present invention relates to a rotor structure for improving the cooling function of a drive motor so that it can proceed smoothly without clogging.

Electric vehicles, generally referred to as eco-friendly vehicles, generate driving power by a driving motor that obtains rotational power through electric energy.

As such, a permanent magnet synchronous motor (PMSM) is widely used as a driving motor used as a power source for an eco-friendly vehicle such as an electric vehicle or a hybrid vehicle.

Permanent magnet type synchronous motors need to maximize the performance of permanent magnets in order to achieve maximum performance under constrained layout conditions. Neodymium (Nd) components in permanent magnets improve the strength of permanent magnets, and dysprosium (Dy) Ingredients improve high temperature demagnetization resistance.

However, rare earth (Nd, Dy) metal components of these permanent magnets are limitedly buried in some countries such as China, are very expensive, and fluctuate in price.

For this reason, in recent years, development of a field winding synchronous motor (WRSM) that can replace a permanent magnet type synchronous motor (PMSM) as a driving motor used as a power source of an eco-friendly vehicle is in progress.

The field winding type synchronous motor replaces the permanent magnet of the permanent magnet type synchronous motor (PMSM) by winding a coil to the rotor as well as the stator to electromagnetize the rotor when current is applied.

In such a field winding type synchronous motor, the rotor is arranged with a certain gap inside the stator, and when power is applied to the stator and the coil of the rotor, a magnetic field is formed, and the rotation of the rotor is prevented by the magnetic action generated between them. Done.

On the other hand, driving motors such as the above-described permanent magnet type synchronous motor or field winding type synchronous motor generate high-temperature heat around the rotor and coils while rotating at high speed.

In addition, due to the heat generated in the rotor and coil as described above, the efficiency of the driving motor may decrease due to power loss and damage to internal parts may occur. Therefore, various types of cooling technologies have been researched and proposed as a technology to prevent this. have.

Referring to FIG. 1, FIG. 1 is a configuration diagram illustrating a rotor structure of an existing driving motor, and the rotation shaft 11 of the rotor 10 has a hollow structure in which one end in the longitudinal direction is closed, and such a rotation shaft ( 11) is a method of providing a cooling function to the rotor 10 by installing a supply pipe 12 for supplying a cooling fluid. Unexplained reference numeral 13 exemplifies the rotor core.

However, in the case of the above-described conventional method, as the rotation shaft 11 of the rotor 10 has a straight tube structure extending with the same outer diameter and inner diameter, the cooling action of the cooling fluid in the rotation shaft 11 is reduced to the rotation shaft ( 11) There was a side that was constantly acting on the whole and proceeded inefficiently, and this appears as a result of lowering the cooling efficiency for the rotor 10.

In an embodiment of the present invention, the rotating shaft of the rotor for a driving motor is divided into two sections of different outer and inner diameters based on the longitudinal direction, and the rotor core is installed in a section having a relatively large outer and inner diameter, thereby reducing the cooling effect. The cooling flow path in the largely exerted area is expanded, and the cooling channel in the area where the cooling action is relatively small is further reduced to improve the overall cooling function and efficiency of the rotor, while supplying and discharging the cooling fluid in the rotating shaft for this purpose. It provides a rotor structure for improving the cooling function of the drive motor so that it can proceed smoothly without such congestion and clogging.

The rotor structure for improving the cooling function of the driving motor according to the embodiment of the present invention is a hollow type with one end closed and the other open open in the longitudinal direction, and the inner space has a relatively large diameter and at the same time closed one end. A rotation shaft formed in the form of a connection of a first space portion adjacent to and a second space portion adjacent to the other open end at the same time having a relatively small diameter, and a rotor core coupled to an outer surface corresponding to the first space portion of the rotation shaft. In addition, the leading end of the cooling fluid supply pipe drawn into the inner space of the rotation shaft through the open other end of the rotation shaft may be introduced to a position beyond the middle of the first space.

In addition, the rotation shaft may be formed to have a difference equivalent to a difference between the diameter of the first space and the diameter of the second space between an outer diameter of one side where the first space is formed and an outer diameter of the other side where the second space is formed. have.

In addition, the connecting portion of the first space part and the second space part may have a shape of an inclined surface extending in a form in which a diameter gradually decreases based on a diameter of the first space part.

In addition, the rotation shaft has one end in the longitudinal direction closed and the other end in the longitudinal direction open so that the inner side forms the first space part and both ends in the longitudinal direction are open, and the inner side forms the second space part. The second unit axis may include a second unit axis coupled to the first unit axis while connecting the second space unit to the first space unit.

In addition, the first unit axis and the second unit axis may be formed of a metal material, respectively, and may be coupled to each other through welding.

In addition, the rotation shaft may be formed in a round shape in which the inner surface of one closed end is convex outward.

According to an embodiment of the present invention, as the rotation axis of the rotor for a drive motor is divided into two sections of different outer and inner diameters based on the longitudinal direction, and the rotor core is installed in a section of relatively large outer and inner diameters, The cooling flow path in the area where the cooling action is largely exerted is expanded, and the cooling channel in the area where the cooling action is exhibited relatively small is further reduced to improve the overall cooling function and efficiency of the rotor. Supply and discharge can proceed smoothly without stagnation and clogging.

1 is a configuration diagram illustrating a rotor structure of an existing drive motor of an electric vehicle

2 is a block diagram illustrating a rotor structure for improving the cooling function of a driving motor according to an embodiment of the present invention.

The following detailed descriptions of the present invention are embodiments in which the present invention may be practiced and refer to the accompanying drawings, which are illustrated as examples of the embodiments. These embodiments will be described in detail sufficient for those skilled in the art to practice the present invention. It should be understood that the various embodiments of the present invention are different from each other, but need not be mutually exclusive. For example, specific shapes, structures, and characteristics described herein may be implemented in other embodiments without departing from the spirit and scope of the present invention in relation to one embodiment. In addition, it should be understood that the location or arrangement of individual components in each described embodiment may be changed without departing from the spirit and scope of the present invention.

Accordingly, the detailed description to be described below is not intended to be taken in a limiting sense, and the scope of the present invention is limited only by the appended claims, along with all scopes equivalent to those claimed by the claims, if appropriately described. Like reference numerals in the drawings refer to the same or similar functions over several aspects.

The terms used in the present invention have been selected from general terms that are currently widely used while considering functions in the present invention, but this may vary according to the intention or precedent of a technician working in the field, the emergence of new technologies, and the like. In addition, in certain cases, there are terms arbitrarily selected by the applicant, and in this case, the meaning of the terms will be described in detail in the description of the corresponding invention. Therefore, the terms used in the present invention should be defined based on the meaning of the term and the overall contents of the present invention, not a simple name of the term.

In the present invention, when a part "includes" a certain component in the whole, it means that other components may be further included rather than excluding other components unless otherwise stated. In addition, “… Wealth”, 　＂… The term “module” refers to a unit that processes at least one function or operation, which may be implemented as hardware or software, or a combination of hardware and software.

A rotor structure for improving the cooling function of a driving motor according to an embodiment of the present invention will be described with reference to FIG. 2.

2 is a block diagram illustrating a structure of a rotor for improving a cooling function of a driving motor according to an embodiment of the present invention.

As shown, the rotor structure for improving the cooling function of the driving motor according to an embodiment of the present invention includes a rotating shaft 100 and a rotor core 200.

The rotation shaft 100 is a hollow type with one end closed and the other end open based on its longitudinal direction, and the inner space of this rotation shaft 100 has a relatively large diameter and is adjacent to the closed end of the rotation shaft 100. One space part 110 and a second space part 120 having a relatively small diameter and adjacent to the open other end of the rotation shaft 100 are connected to each other.

The rotor core 200 is coupled to an outer surface corresponding to the first space 110 of the rotation shaft 100.

In addition, the cooling fluid supply pipe 300 is introduced into the inner space of the rotation shaft 100 through the open other end of the rotation shaft 100, and the tip of the cooling fluid supply pipe 300 in the direction in which the rotation shaft 100 is drawn is first It is introduced to a position beyond the middle of the space part 110. Here, the rotation shaft 100 may be formed in a round shape in which the inner surface of the closed end is convex outward.

By the above-described configuration, as the first space part 110 forming a part of the cooling flow path in the rotation shaft 100 is formed in a shape having a larger diameter, a larger amount of cooling water in the cooling flow path in the rotation shaft 100 Can be supplied, and thus the cooling function and efficiency for the rotor can be greatly improved. In addition, as the rotor core 200 is coupled to the outer diameter of the side where the first space portion 110 of the rotation shaft 100 is formed, a cooling function and efficiency for the rotor may be further improved.

In addition, as the inner surface of the rotation shaft 100 is formed in an outwardly convex round shape, one end of the first space portion 110 forming a part of the cooling passage in the rotation shaft is formed in a round shape, and thus The cooling fluid discharged into the first space part 110 through the cooling fluid supply pipe 300 collides with the closed end of the first space part 110 and at the same time prevents the first space part from being blocked and stagnant as much as possible. It flows naturally along the round surface of (110) and is discharged by changing the direction.

In other words, the supply and discharge of the cooling fluid in the first space 110 is smoothly performed, and this leads to the effect of rapidly discharging the newly supplied cooling fluid after the cooling action, and at the same time continuously supplying the cooling fluid. As a result, the cooling function and efficiency for the rotor are greatly increased.

In addition, the rotation shaft 100 has an inner diameter of the first space portion 110 and a second space portion between the outer diameter of one side where the first space portion 110 is formed and the outer diameter of the other side where the second space portion 120 is formed. 120) can be formed to have a difference equivalent to the difference between the inner diameters. In other words, the outer diameter of one side of the rotation shaft 100 forming the first space portion 110 is larger than the outer diameter of the other side of the second space portion 120.

According to this embodiment, the rotation shaft 100 has a combined form of the first unit shaft 140 and the second unit shaft 150, and the first unit shaft 140 has one end in the longitudinal direction closed and the longitudinal direction The other end of the is open to form a first space part 110 inside. In addition, the second unit shaft 150 is in a state in which both ends in the longitudinal direction are open and the inner side forms a second space part 120 to connect the second space part 120 to the first space part 110. It is combined with the first unit shaft 140.

In addition, in the present embodiment, the first unit shaft 140 and the second unit shaft 150 are each formed of a metal material and are coupled to each other through welding, but the present invention is not limited thereto.

By the above-described configuration, as the second space portion 120 forming a part of the cooling passage in the rotation shaft 100 is formed to have a relatively small diameter, the rotation shaft 100 leads to a reduction in the overall outer diameter of the rotation shaft 100. The former cooling function can be further improved.

In addition, the rotation shaft 100 is an inclined surface 130 in which the connecting portion of the first space part 110 and the second space part 120 extends in a form in which the inner diameter gradually decreases based on the inner diameter of the first space part 110. ) May be in the form of.

By the above-described configuration, when the cooling fluid having a cooling action in the first space part of the rotation shaft is discharged in the direction of the second space part, it is guided along the inclined surface, and smoothly flows into the second space part having a smaller diameter than the first space part, and Can be discharged. To further explain, the phenomenon that the cooling fluid moving in the direction of the second space part after the cooling action in the first space part collides with the step surface due to the difference in diameter between the first space part and the second space part and is blocked at the same time, thereby preventing the phenomenon of stagnation. It does not occur and smoothly flows into the second space. And this leads to a result that the supply and discharge of the cooling fluid in the rotation shaft proceeds smoothly without clogging or stagnation, so that the cooling function and efficiency of the rotor can be greatly improved.

As can be seen from the above-described embodiment, the rotor structure for improving the cooling function of the drive motor according to the present invention is provided in two sections of an outer diameter and an inner diameter in which the rotation axis of the rotor for the drive motor is different from the length direction. The rotor core is installed in sections of relatively large outer and inner diameters, and accordingly, the cooling channel in the area where the cooling action is exhibited is more expanded, and the cooling channel in the area where the cooling action is exhibited relatively small is further reduced. As a result, the overall cooling function and efficiency for the rotor are improved.

In addition, the supply and discharge of the cooling fluid in the rotating shaft for this purpose can be smoothly performed without stagnation and clogging.

As described above, in the present description, specific matters such as specific components, etc., and limited embodiments and drawings have been described, but this is provided only to help a more general understanding of the present invention, and the present invention is limited to the above embodiments. No, various modifications and variations are possible from these descriptions by those of ordinary skill in the field to which the present invention belongs.

Therefore, the spirit of the present invention is limited to the described embodiments and should not be written, and all things having equivalent or equivalent modifications to the claims as well as the claims to be described later belong to the scope of the inventive concept.

Claims

In the longitudinal direction, one end is closed and the other end is hollow, and the inner space has a relatively large diameter, and a first space portion adjacent to the closed end and a first space portion adjacent to the closed end and a first space adjacent to the open other end at the same time. A rotating shaft made in the form of a connection of two spaces; And

And a rotor core coupled to an outer surface corresponding to the first space portion of the rotation shaft,

A rotor structure for improving the cooling function of a driving motor in which the leading end of the cooling fluid supply pipe drawn into the inner space of the rotary shaft through the open other end of the rotary shaft is drawn to a position beyond the middle of the first space.
The method of claim 1,

The rotation shaft is formed to have a difference equivalent to a difference between the diameter of the first space and the diameter of the second space between an outer diameter of one side where the first space is formed and an outer diameter of the other side where the second space is formed. Rotor structure to improve the cooling function of the drive motor.
The method of claim 2,

A rotor for improving the cooling function of a driving motor, characterized in that the connecting portion of the first space part and the second space part has a shape of an inclined surface extending in a form in which the diameter of the first space part is gradually reduced based on the diameter of the first space part rescue.
The method of claim 2,

The rotation shaft has one end in the longitudinal direction closed and the other end in the longitudinal direction open to open the first unit shaft and both ends in the longitudinal direction to form the first space, and to form the second space at the inside. 2 A rotor structure for improving a cooling function of a driving motor, comprising: a second unit shaft coupled to the first unit shaft while connecting the space unit to the first space unit.
The method of claim 4,

The first unit shaft and the second unit shaft are each formed of a metal material and are coupled to each other through welding.
The method of claim 1,

The rotating shaft is a rotor structure for improving the cooling function of the driving motor, characterized in that the inner surface of the closed end is formed in a round shape convex outward.