Motor cooling system

Abstract

The present disclosure relates to a motor cooling system that is a system for cooling a stator core of an electric motor. The motor cooling system according to the present disclosure is advantageous in that the motor cooling system can be cooled by improving the typical design of the housing supporting the stator core to increase the fluid guide and nozzle shape, or by applying a nozzle ring formed in a curved shape and capable of spraying a cooling fluid after being received and stored to the end of the housing. The number of components may be minimized, and cooling efficiency may be maximized using uniform distribution of a cooling fluid to a heat-generating region.

Description

Technical Field

[0001] The following disclosure relates to a system for cooling a stator core of an electric motor. Background Art

[0002] The heat generated in the electric motor is mainly caused by the loss occurring in the stator coil and the electrical steel sheet, and if the generated heat continues to be in an uncooled state, this may cause the loss of the components applied to the motor. Therefore, it is preferable to maintain proper cooling (direct cooling) using various fluids such as air, water, and oil to stably operate the motor and extend the life of the motor. In the conventional technology, various components and methods such as pipes, ducts, nozzles, and agitation have been used for cooling, and the fluidity of the cooling fluid has been improved to increase the cooling efficiency.

[0003] However, in conventional technology, there is a common problem that when the motor is directly cooled, the fluid cannot be evenly distributed to the heat generating area. In particular, the heat generation rate in the end coil area is high, which has a significant impact on the motor components if cooling is not performed locally. In order to cause local cooling, various methods have been used. However, in the pipe method, there are problems of increased number of components and high cost, and in the reflector method, there is a problem of poor cooling efficiency. Utility Model Content

[0004] One embodiment of the present disclosure is directed to providing a motor cooling system that can minimize the number of components and maximize cooling efficiency by uniformly distributing cooling fluid to heat-generating areas by improving the typical design of a housing supporting a stator core (core press-fit stop end) to increase fluid guides and nozzle shapes.

[0005] Another embodiment of the present disclosure is directed to providing a motor cooling system capable of maximizing cooling efficiency by uniformly distributing cooling fluid to a heat generating area by applying a nozzle ring formed in a curved shape, and capable of spraying the cooling fluid after the cooling fluid is received and stored in an end of a housing.

[0006] In one general aspect, a motor cooling system includes: a cylindrical stator core, a coil being wound to be mounted on the inner side of the stator core; a housing mounted on the outer side of the stator core to support the position of the stator core, and the housing having an injection port formed through the housing to inject a cooling fluid; and a cooling fluid injection portion including a structure for guiding the cooling fluid injected through the injection port and flowing between the stator core and the housing to flow toward the coil.

[0007] The stator core may include at least one first cooling channel, which is a groove formed in the outer surface of the stator core along the axial direction, and the shell may include at least one second cooling channel, which is a groove formed in the inner surface of the shell along the circumferential direction.

[0008] The stator core may include two or more cooling lines, each cooling line including two or more first cooling passages formed adjacent to each other, and the cooling lines may be formed to be spaced apart from each other at predetermined intervals in the circumferential direction.

[0009] The cooling fluid injection portion may include a nozzle ring coupled to one end of the housing, and the nozzle ring may include: a fixing portion, the fixing portion being coupled to one end of the inner surface of the housing; a fluid storage portion, the fluid storage portion having one end integrally formed with the fixing portion and the other end in contact with one end surface of the stator core; and a first fluid injection hole, the first fluid injection hole being formed through the fluid storage portion.

[0010] The cooling fluid injection portion may include a core support end formed at one end of the shell, and the core support end may include: a first support end, which extends from the inner surface of the shell in a radial direction; a second support end, which extends from a distal end of the first support end in the axial direction; and a second fluid injection hole, which is formed through at least one of the first support end or the second support end.

[0011] The motor cooling system may further include a terminal bus bar, which includes a first connection portion connected to the shell and a second connection portion connected to the coil, wherein the cooling fluid injection portion may further include an extension support portion, which is assembled between the stator core and the shell while covering the outer surface of the stator core, and one end of the extension support portion is connected to the first connection portion and the second connection portion of the terminal bus bar.

[0012] The extension support portion may include: a cylindrical first extension portion, which extends to cover the outer surface of the stator core; and a second extension portion, which is arranged between the first extension portion and the first connecting portion and the second connecting portion to cover and protect the area where the coil is arranged, and the second extension portion can be formed to be recessed inward from the first extension portion.

[0013] The inner surface of the first extension portion contacting the stator core may include a curved surface matching the outer surface of the stator core, and the outer surface of the first extension portion contacting the housing may be formed to be gradually inclined relative to the stator core toward a distal end of the first extension portion.

[0014] The housing may further include a fixing groove formed in an inner surface of the housing to correspond to an inclined outer surface of the first extension portion.

[0015] The stator core may further include a support groove formed to be recessed from the outer surface of the stator core and extending in a circumferential direction, and the first extension portion may include a protrusion protruding from an inner surface of the first extension portion to correspond to the support groove.

[0016] The advantage of the motor cooling system having the above-mentioned construction is that the number of components can be minimized by improving the typical design of the housing supporting the stator core (core press-fit stop end) to increase the fluid guide and nozzle shape, and the cooling efficiency can be maximized by evenly distributing the cooling fluid to the heat-generating area.

[0017] The motor cooling system having the above configuration also has the advantage that by applying a nozzle ring formed in a curved shape and being able to spray cooling fluid after being received and stored at the end of the housing, cooling efficiency can be maximized by uniformly distributing the cooling fluid to the heat generating area. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 is an axial cross-sectional view of a motor cooling system according to the present disclosure.

[0019] Figure 2 is a radial cross-sectional view of a stator core according to the present disclosure.

[0020] Figure 3 is a perspective view of a stator core according to the present disclosure.

[0021] Figure 4 is a partial stereoscopic view of a housing according to the present disclosure.

[0022] Figure 5 is a perspective view of a nozzle ring according to the present disclosure.

[0023] Figure 6 is a partial perspective view showing a coupling relationship among a nozzle ring, a housing, and a stator core according to the present disclosure.

[0024] Figure 7 is a partial perspective view of a housing in which a core support end according to the present disclosure is formed.

[0025] Figure 8is an axial cross-sectional view of a motor cooling system to which an extended support portion is applied according to the present disclosure.

[0026] Fig. 9 is an axial cross-sectional view showing an embodiment of an extended support portion according to the present disclosure.

[0027] Detailed description of the main components

[0028] 1000: Motor cooling system

[0029] 100: stator core

[0030] 110: Cooling pipe

[0031] 111: First cooling channel

[0032] 120: Support groove

[0033] 200: Shell

[0034] 210: Injection port

[0035] 220: Second cooling channel

[0036] 230: Fixed groove

[0037] 240: Ring connection groove

[0038] 300: Terminal busbar

[0039] 310: First connection part

[0040] 320: Second connection part

[0041] 400: Cooling fluid injection part

[0042] 410: Nozzle ring

[0043] 411: Fixed part

[0044] 412: Fluid storage unit

[0045] 413: First fluid injection hole

[0046] 420: Core support end

[0047] 421: First support end

[0048] 422: Second support end

[0049] 423: Second fluid injection hole

[0050] 430: Extended support

[0051] 431: First extension

[0052] 432: Second extension

[0053] 433: Protrusion

[0054] C: Coil DETAILED DESCRIPTION

[0055] Hereinafter, the technical concept of the present disclosure will be described in more detail with reference to the accompanying drawings. In addition, the terms or words used in the specification and claims herein should not be interpreted as limited to the ordinary meaning or dictionary meaning, but should be interpreted as the meaning and concept corresponding to the technical concept of the present disclosure, which is based on the principle that the inventor can appropriately define the concept of the term to describe his / her utility model in the best way.

[0056] In the following, reference will be made to Figure 1 A basic configuration of a motor cooling system 1000 according to the present disclosure is described.

[0057] like Figure 1 As shown, the motor cooling system 1000 according to the present disclosure may include: a cylindrical stator core 100, which is hollow at the center, and the coil C is wound to fit on the inner side thereof; and a housing 200, which is fitted on the outer side of the stator core 100 to support the position of the stator core 100, and has an injection port 210 formed therethrough to inject a cooling fluid. More specifically, the stator core 100 may include a groove of a predetermined depth formed in a radial direction to communicate with the central hollow portion, and a plurality of grooves may be formed to be spaced apart from each other at predetermined intervals in the circumferential direction. The strands of the coil C may be wound to fit into each of the grooves.

[0058] In addition, the motor cooling system 1000 according to the present disclosure may include a terminal bus bar 300 ( Figure 1 ). The terminal bus bar 300 may be coupled to the housing 200 by bolting to form a first coupling portion 310, and coupled to the coil C by welding to form a second coupling portion 320. Therefore, the position of the coil C may depend on the housing 200, and the housing 200 may be made of a conductive material to be electrically connected to the coil C.

[0059] In addition, the motor cooling system 1000 according to the present disclosure may include a cooling fluid injection portion 400. The cooling fluid injection portion 400 may include a processed shape (protrusion or groove) applied to the housing 200 or the terminal bus bar 300, or may include a component additionally attached to the housing 200 or the stator core 100. The specific configuration thereof will be described in the following paragraphs.

[0060] The cooling fluid injection portion 400 may inject the cooling fluid injected through the injection port 210 formed in the housing 200 to the coils C, more specifically, to the end coils C led out toward the outside of the stator core 100. By including the cooling fluid injection portion 400, the cooling fluid may be more effectively brought into contact with the end coils C, thereby improving cooling efficiency.

[0061] In the following, reference will be made to Figures 2 to 4 The path along which the cooling fluid flows according to the present disclosure is described in more detail.

[0062] like Figure 2 and Figure 3 As shown, the stator core 100 may include at least one first cooling channel 111, which is a groove formed in the axial direction on the outer surface thereof. By including the first cooling channel 111, the cooling fluid introduced through the injection port 210 of the housing 200 can flow along the side surface of the stator core 100 to cool the stator core 100.

[0063] In this case, the stator core 100 may include two or more cooling lines 110 formed adjacent to each other, each cooling line 110 including a first cooling channel 111. The two or more cooling lines 110 may be formed to be spaced apart from each other at a predetermined interval in the circumferential direction. In this case, the distance between the first cooling channels 111 spaced apart from each other in one cooling line 110 may be shorter than the distance between the cooling lines 110 spaced apart from each other. Therefore, the first cooling channel 111 may serve as a guide protrusion so that the cooling fluid flows along the cooling line 110, that is, moves in the axial direction.

[0064] In addition, if Figure 4 As shown, the housing 200 may include at least one second cooling channel 220, which is a groove formed in the inner surface thereof along the circumferential direction. Two or more second cooling channels 220 may be formed, and the second cooling channels 220 may be formed to be spaced apart from each other in the axial direction. In addition, at least one second cooling channel 220 may be directly connected to the injection port 210. Therefore, the cooling fluid may flow in the order of the injection port 210 → one second cooling channel 220 → the first cooling channel 111 → another second cooling channel 220, thereby cooling the entire side surface of the stator core 100 at the same time, and in addition, the cooling efficiency is improved.

[0065] In addition, the housing may be formed in such a manner that the cooling fluid injection portion or a partial configuration of the cooling fluid injection portion is coupled to each of its two ends. For example, the ring coupling groove 240 for inserting the nozzle ring 410 as the first embodiment of the cooling fluid injection portion 400 may be formed at one end of the housing, or the core support end 420 as the second embodiment of the cooling fluid injection portion 400 may be integrally formed at one end of the housing.

[0066] Each embodiment of the cooling fluid injection portion 400 will be described in detail in the following paragraphs.

[0067] In the following, reference will be made to Figure 5 and Figure 6 The first embodiment of the cooling fluid injection portion 400 according to the present disclosure is described in more detail.

[0068] like Figure 5 As shown, the cooling fluid injection portion 400 may include a nozzle ring 410 coupled to one end of the housing 200. The nozzle ring 410 may be made of a material having elasticity and having an elastic force greater than or equal to a predetermined value. For example, the nozzle ring 410 may be made of rubber or silicone. Figure 6 As shown, the nozzle ring 410 may include a fixing portion 411 coupled to one end of the inner side surface of the housing 200. In addition, the nozzle ring 410 may include a fluid storage portion 412 having one end integrally formed with the fixing portion 411 and the other end in contact with one end surface of the stator core 100. In addition, the nozzle ring 410 may include a first fluid injection hole 413 formed through the fluid storage portion 412.

[0069] More specifically, the fluid storage portion 412 may be formed to have a curved surface, and a portion of the fluid storage portion 412 may protrude toward the end coil C after being bent to form a question mark shape. Therefore, the cooling fluid may stay in the fluid storage portion 412 for a predetermined period of time. In addition, the first fluid injection hole 413 formed in the fluid storage portion 412 may be formed at a position that protrudes the highest toward the end coil C in the axial direction relative to the fixing portion 411, thereby injecting the cooling fluid toward the end coil C at a maximum flow rate and a maximum flow pressure.

[0070] In the following, reference will be made to Figure 7 and Figure 8 The second embodiment of the cooling fluid spraying portion 400 according to the present disclosure is described in more detail.

[0071] like Figure 7As shown, the cooling fluid injection portion 400 may include a core support end 420 formed at one end of the housing 200. The core support end 420 preferably includes a first support end 421 extending from the inner side surface of the housing 200 in a radial direction, a second support end 422 extending from a distal end of the first support end 421 in an axial direction, and a second fluid injection hole 423 formed through the first support end 421 or the second support end 422.

[0072] More specifically, the first support end 421 and the second support end 422 may be perpendicular to each other, and the first support end 421 and the second support end 422 may be integrally formed with the housing 200, and may be formed together when the housing 200 is injection molded. In addition, the first support end 421 may have a greater thickness than the second support end 422. Therefore, even if the cooling fluid flowing out between the housing 200 and the stator core 100 directly hits the first support end 421, the first support end 421 may maintain structural stability for a long time without being damaged.

[0073] In addition, the second fluid injection hole 423 may be formed to penetrate the first support end 421 and the second support end 422. As an example, Figure 7 As shown, the second fluid injection hole 423 may be formed by passing through the first support end 421, the second support end 422, and the corner where the first support end 421 and the second support end 422 intersect. shaped hole. Alternatively, the second fluid injection hole 423 may be separately provided in each of the first support end 421 and the second support end 422. However, in this case, each second fluid injection hole 423 may be formed close to the corner where the first support end 421 and the second support end 422 intersect, that is, at a position where the distance from the corner is less than a predetermined reference value. Therefore, the second fluid injection hole may be formed at a position protruding closest to the end coil C relative to the first support end 421 and the second support end 422, thereby spraying the cooling fluid toward the end coil C at a maximum flow rate and a maximum flow pressure.

[0074] At this time, the core support end 420 may be designed by modifying the compression prevention end provided in the typical design of the housing 200. By including the core support end 420, the motor cooling system 1000 according to the present disclosure can not only spray the cooling fluid but also prevent the stator core 100 from being pushed out of the housing 200. To this end, the distal end of the second support end 422 may be formed to contact the end of the stator core 100.

[0075] In the following, reference will be made to Figure 8 A third embodiment of the cooling fluid spraying portion 400 according to the present disclosure is described.

[0076] like Figure 8As shown, the cooling fluid injection portion 400 may include an extension support portion 430. The extension support portion 430 may be assembled between the stator core 100 and the housing 200 while covering the outer surface of the stator core 100, and one end of the extension support portion 430 is coupled to the first coupling portion 310 and the second coupling portion 320 of the terminal bus bar 300. The extension support portion may include: a cylindrical first extension portion 431, which extends to cover the outer surface of the stator core 100; and a second extension portion 432, which is disposed between the first extension portion 431 and the first coupling portion 310 and the second coupling portion 320 to cover and protect the area where the coil C is disposed.

[0077] By including the extension support portion 430, the cooling fluid ejected from the first cooling channel 111 and flowing out of the first cooling channel 111 can be stored in the extension support portion 430 without leaking to the outside, thereby maximizing the cooling efficiency. In this case, the second extension portion 432 can be formed to be recessed inside the first extension portion 431. Therefore, the second extension portion 432 can be positioned closer to the end coil C, and the contact between the cooling fluid and the end coil C can be increased, resulting in an increase in cooling efficiency.

[0078] In addition, the inner surface of the first extension portion 431 contacting the stator core 100 may include a curved surface matching the outer surface of the stator core 100. In addition, the outer surface of the first extension portion 431 contacting the housing 200 may be formed to be gradually inclined relative to the stator core 100 toward the distal end of the first extension portion 431. That is, the first extension portion 431 may be formed to have a thickness that becomes smaller toward its distal end. Therefore, elasticity may be formed at the distal end of the first extension portion 431, and the adhesion between the first extension portion 431 and the stator core 100 may be increased.

[0079] In addition, the housing 200 may further include a fixing groove 230 formed in the inner surface thereof to correspond to the distal end of the outer surface of the first extension 431. In this case, the fixing groove 230 may be formed in the form of an inclined surface or a step having the same slope as the distal end of the first extension 431. Therefore, the housing 200 may press the first extension 431 on the outer surface of the first extension 431 and further fix the position of the extension support. Therefore, even if vibration continuously occurs in the motor, structural stability may be ensured because the extension support 430, the stator core 100, and the housing 200 are not separated from each other.

[0080] In addition, if Fig. 9As shown, the stator core 100 may further include a support groove 120 formed to be recessed in a circumferential direction in an outer surface thereof, and the first extension portion 431 may include a protrusion 433 protruding from an inner surface thereof to correspond to the support groove 120. In this case, the protrusion 433 may be formed to correspond to the support groove 120, excluding an area where a cooling fluid flow channel is formed. Therefore, the connection between the first extension portion 431 and the stator core 100 can be more firmly supported, and further, the position of the extension support portion can be fixed. Ultimately, even if vibration occurs continuously in the motor, structural stability can be ensured because the extension support portion 430, the stator core 100 and the housing 200 are not separated from each other.

[0081] This technical concept should not be interpreted as being limited to the above-mentioned embodiments of the present disclosure. The present disclosure is applicable to various scopes and can be modified in various ways by those skilled in the art without departing from the gist of the present disclosure. Therefore, these improvements and modifications fall within the scope of protection of the present disclosure as long as they are obvious to those skilled in the art.

Claims

1. A motor cooling system, characterized in that: The motor cooling system comprises: a cylindrical stator core on the inner side of which the coil is wound to fit; a housing fitted on an outer side of the stator core to support a position of the stator core and having an injection port formed through the housing to inject a cooling fluid; and A cooling fluid spraying portion includes a structure for guiding the cooling fluid injected through the injection port and flowing between the stator core and the housing to flow toward the coil.

2. The motor cooling system according to claim 1, characterized in that: The stator core includes at least one first cooling channel which is a groove formed in an outer surface of the stator core in an axial direction, and The housing includes at least one second cooling channel which is a groove formed in an inner surface of the housing in a circumferential direction.

3. The motor cooling system according to claim 2, characterized in that: The stator core includes two or more cooling lines, each cooling line includes two or more first cooling channels formed adjacent to each other, and The cooling lines are arranged to be spaced apart from each other at predetermined intervals in the circumferential direction.

4. The motor cooling system according to claim 2, characterized in that: The cooling fluid injection portion includes a nozzle ring coupled to one end of the housing, and The nozzle ring comprises: a fixing portion coupled to one end of the inner surface of the housing; a fluid storage portion having one end formed integrally with the fixing portion and the other end in contact with one end surface of the stator core; and A first fluid injection hole is formed through the fluid storage portion.

5. The motor cooling system according to claim 2, characterized in that: The cooling fluid injection portion includes a core supporting end formed at one end of the housing, and The core support end comprises: a first support end extending in a radial direction from the inner surface of the housing; a second supporting end extending in the axial direction from a distal end of the first supporting end; and A second fluid injection hole is formed through at least one of the first supporting end or the second supporting end.

6. The motor cooling system according to claim 1, characterized in that: The motor cooling system further includes a terminal bus bar including a first coupling portion coupled to the housing and a second coupling portion coupled to the coil, The cooling fluid injection portion further includes an extended support portion, which is assembled between the stator core and the housing while covering the outer surface of the stator core, and one end of the extended support portion is connected to the first connection portion and the second connection portion of the terminal busbar.

7. The motor cooling system according to claim 6, characterized in that: The extended support portion comprises: a cylindrical first extension portion extending to cover the outer surface of the stator core; and a second extending portion disposed between the first extending portion and the first and second coupling portions to cover and protect an area where the coil is disposed, and The second extending portion is formed to be recessed inwardly from the first extending portion.

8. The motor cooling system according to claim 7, characterized in that: The inner surface of the first extension portion contacting the stator core includes a curved surface matching the outer surface of the stator core, and An outer surface of the first extension portion contacting the housing is formed to be gradually inclined relative to the stator core toward a distal end of the first extension portion.

9. The motor cooling system according to claim 8, characterized in that: The housing further includes a fixing groove formed in an inner surface of the housing to correspond to an inclined outer surface of the first extension portion.

10. The motor cooling system according to claim 7, characterized in that: The stator core further includes a support groove formed to be recessed from the outer surface of the stator core and extending in a circumferential direction, and The first extension portion includes a protrusion protruding from an inner surface of the first extension portion to correspond to the support groove.

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