Axial oil cooling of conductive elements in electric machine

Abstract

A cooling ring for an electric machine, the cooling ring comprising: a first portion having an outer surface having a first end and a second end and a hollow interior extending along a longitudinal axis of the cooling ring wherein the hollow interior is configured to surround the first end of a stator; and a shoulder extending radially outward at the first end of the first portion, where the shoulder includes an axial opening extending in a first direction, where the first direction is substantially parallel to the longitudinal axis of the cooling ring.

Description

Axial oil cooling of conductive elements in motor Technical Field

[0001] This disclosure generally relates to electric motors, particularly electric motors in the automotive field. More specifically, this disclosure relates to a ring for a stator cooling assembly of an electric motor, such as those used in electric vehicles. Background Technology

[0002] Electric motors generate heat during operation. Devices for cooling motors can include a stator back water jacket or the use of a cooling fluid such as oil to cool the motor's conductive elements. Oil-cooled motors are very effective at cooling the rotor, but cooling the stator assembly is complex. In particular, it is difficult to effectively cool the conductive elements of the stator assembly that extend beyond the stator windings.

[0003] As the temperature of a motor increases, its performance may degrade. To maintain motor performance within a desired temperature range, the motor assembly can distribute cooling fluid to the windings of the motor assembly in the radial direction. Overheated conductive elements (such as busbars) may suffer from high temperatures. This could be a result of their proximity to the cooling fluid, for example, when the conductive elements are relatively far from existing cooling fluid distribution mechanisms.

[0004] However, there is a trend toward making things more compact, which may make it more difficult to fit space into the distribution of cooling fluid in the axial direction to other conductive elements.

[0005] Therefore, an improved stator cooling assembly is desired for distributing cooling fluids such as oil, liquid, gas, or other fluids to cool the motor.

[0006] The background section relating to the use of stator cooling assemblies is intended only to provide a background overview of some current problems and is not intended to be exhaustive. Further contextual information will become apparent to those skilled in the art after reading the following detailed description. Summary of the Invention

[0007] Providing a ring with an axial opening enables the distribution of cooling fluid to a conductive element positioned axially relative to the cooling ring.

[0008] Cooling rings can distribute cooling fluid in multiple directions, which reduces or eliminates the risk of motor overheating. For example, cooling rings can distribute cooling fluid in both the radial and axial directions.

[0009] The cooling ring can surround the stator windings, positioning the windings radially relative to the cooling ring. In addition to distributing cooling fluid to the windings, the axial opening can also be configured to distribute cooling fluid to other conductive elements, such as busbars.

[0010] During motor operation, the stator windings and busbars, or any other conductive elements electrically connected to the windings, can generate heat. As the motor temperature rises, its performance may degrade. Distributing cooling fluid to the conductive elements electrically connected to the windings can keep the motor within a desired temperature range. For example, cooling fluid can be distributed in multiple directions within the motor assembly.

[0011] Including axial openings in the cooling ring allows cooling fluid to be distributed to conductive elements beyond the stator windings without increasing the size of the motor housing or redesigning any other components of the motor assembly. Therefore, it is possible to maintain the motor temperature without introducing additional components into the motor housing system.

[0012] According to one embodiment, the cooling ring includes one or more radially inward recesses spaced apart at at least a portion of the circumference of the first portion at a first end. These inward recesses can be incorporated into available space within an existing machine housing. Furthermore, the inward recesses can reduce the amount of cooling fluid required in the motor housing by utilizing existing cooling fluid distribution mechanisms. For example, existing cooling fluid reservoirs can be used to cool additional conductive elements.

[0013] According to one embodiment, the radially inward recess includes a shoulder extending radially outward at a first end of the first portion and an axial opening. This shoulder provides a surface for the axial opening without increasing the circumference of the cooling ring.

[0014] According to one embodiment, a cooling ring is disposed between the housing and a first end of the stator, wherein the location of the cooling ring creates a gap between the outer surface of the housing and the cooling ring. This gap forms a sealed chamber or reservoir for receiving cooling fluid so that the cooling fluid can be distributed through an axial opening.

[0015] According to one embodiment, the axial opening is axially oriented toward the first conductive element, wherein the first conductive element is substantially in a first direction relative to the axial opening.

[0016] According to one embodiment, the first conductive element can be a busbar, winding, or I-pin, or any other conductive element of the motor assembly. Different configurations of the motor may include conductive elements in different locations. The cooling ring of this embodiment can cool any conductive element in the axial direction relative to the cooling ring. In this way, the motor temperature can be kept within an operational range regardless of the configuration.

[0017] According to one embodiment, the recessed gap is configured to be filled with cooling fluid. The gap can be configured to maintain the pressure of the cooling fluid, such that the cooling fluid passes through the axial opening with sufficient force to reach the target conductive element.

[0018] According to one embodiment, the cooling ring may further include a radial opening extending in a second direction, wherein the second direction is substantially perpendicular to the first direction, and wherein cooling fluid passes through the radial opening substantially in the second direction. This provides the ability to cool the conductive element in both the radial and axial directions of the cooling ring.

[0019] According to one embodiment, the radial opening faces radially toward the second conductive element. The second conductive element may be a stator winding surrounded by a cooling ring.

[0020] According to one embodiment, a second conductive element is located at a first end of the stator. A cooling ring may surround the conductive element at the first end of the stator. In addition to other conductive elements connected to the windings, radial openings may distribute cooling fluid to the conductive elements, such as the stator windings.

[0021] According to one embodiment, the second conductive element is a stator winding and / or a stator I-pin. A cooling ring can be configured to distribute cooling fluid to various second conductive elements, wherein the cooling ring is configured as a conductive element surrounding any configuration of the motor.

[0022] According to one embodiment, the cooling ring is formed of plastic. The plastic can be shaped to withstand the temperature of the motor without conducting heat itself. Furthermore, plastic is an easily moldable material, suitable for manufacturing cooling rings for motors of any shape and size.

[0023] According to one embodiment, a stator cooling assembly for an electric motor includes: a housing, wherein the housing includes a cooling fluid reservoir and a hollow opening, wherein the cooling fluid reservoir includes a fluid opening extending radially inward from the cooling fluid reservoir to the hollow opening; a stator, wherein the stator includes a core and a first conductive element extending axially from the core, wherein the core includes a cooling fluid channel, and wherein the fluid channel is positioned aligned with the fluid opening of the housing; and a cooling ring, wherein the cooling ring includes: a first portion having an outer surface and a hollow interior, the outer surface having a first end and a second end, and the hollow interior extending along a longitudinal axis of the cooling ring, wherein the first portion has a first end and a second end. The housing has a hollow interior configured to surround the first conductive element of the stator; a shoulder extending radially outward at the first end of the first portion, wherein the shoulder includes an axial opening extending along a first direction, wherein the first direction is substantially parallel to the longitudinal axis of the cooling ring, wherein the cooling ring is positioned in the hollow opening of the housing such that the second end is adjacent to the core, the inner surface of the housing and the outer surface of the cooling ring form a gap, and the axial opening faces the second conductive element, wherein the stator cooling assembly is configured to dispense cooling fluid from the cooling fluid reservoir through the cooling fluid channel to fill the gap, and to further dispense the cooling fluid to the second conductive element through the axial opening.

[0024] This configuration of the motor assembly provides cooling fluid distribution without requiring additional components. The cooling fluid can be drained from the component to be cooled and recirculated for reuse in the cooling conduction elements. Attached Figure Description

[0025] The present disclosure will now be described in more detail with reference to the accompanying drawings, which illustrate an embodiment of the present disclosure: FIG1A is a perspective view of a cooling ring for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; FIG1B is an end view of the cooling ring of FIG1A; FIG1C is a cross-sectional view of the cooling ring of FIG1A; FIG2A is a perspective view of a cooling ring with recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; FIG2B is an end view of the cooling ring of FIG2A; FIG2C is a cross-sectional view of the cooling ring of FIG2A; FIG3A is a perspective view of a cooling ring with multiple recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; FIG3B is an end view of the cooling ring of FIG3A; FIG3C is a cross-sectional view of the cooling ring of FIG3A; FIG4A is a cooling ring with multiple recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure. Figure 4B is an end view of the cooling ring of Figure 4A; Figure 4C is a cross-sectional view of the cooling ring of Figure 4A; Figure 5A is a perspective view of a cooling ring with angled recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; Figure 5B is an end view of the cooling ring of Figure 5A; Figure 5C is a cross-sectional view of the cooling ring of Figure 5A; Figure 6A is a perspective view of a cooling ring with multiple angled recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; Figure 6B is an end view of the cooling ring of Figure 6A; Figure 6C is a cross-sectional view of the cooling ring of Figure 6A; Figure 7A is a perspective view of a cooling ring with multiple angled recesses for distributing cooling fluid in the axial direction according to at least one example of the present disclosure; Figure 7B is an end view of the cooling ring of Figure 7A; Figure 7C is a cross-sectional view of the cooling ring of Figure 7A; Figure 8 is a cross-sectional view of a motor housing including the cooling ring.

[0026] Figure 8A is a close-up view of the axial opening of the motor housing shown in Figure 8.

[0027] Figures 9A and 9B show a comparison chart of the operating temperatures of motors in use with cooling rings having axial openings and those without axial openings. Detailed Implementation

[0028] This disclosure relates to a cooling ring with axial openings, which can be used in an electric motor housing to distribute cooling fluid to conductive elements, such as stator windings. One or more axial openings may be configured to distribute cooling fluid in an axial direction to additional conductive elements located axially relative to the cooling ring.

[0029] The axial opening of the cooling ring distributes cooling fluid, such as oil, axially relative to the cooling ring to the conductive elements without requiring additional features in the motor assembly. As the trend towards compactness continues, it is advantageous to introduce functionality without introducing additional components. For example, oil can pass through the axial opening of the cooling ring to spray oil onto the conductive elements of the motor assembly, such as busbars.

[0030] The axial opening of the cooling ring distributes cooling fluid (such as oil) to the conductive elements in the axial direction, while the radial opening distributes cooling fluid to other conductive elements (such as the stator windings).

[0031] This disclosure effectively reduces the temperature of the motor to maintain it within a desired range. For example, it may be desirable to keep the temperature of the conductive elements below the highest temperature at which the motor's performance degrades to an undesirable level. Keeping the temperature below the highest temperature allows the motor's performance to remain at the desired level because less current is required to achieve the desired torque, and because the conductive elements provide lower resistance at cooler temperatures. This disclosure can reduce the temperature of the motor compared to a motor without an axial opening for distributing cooling fluid in the axial direction. Therefore, the efficiency of the motor is improved compared to a motor operating without axial cooling fluid distribution.

[0032] Figure 1A is a perspective view of the cooling ring 100, Figure 1B is an end view of the cooling ring 100, and Figure 1C is a cross-sectional view of the cooling ring 100. The cooling ring 100 includes an outer surface 102 and a hollow interior 104. The cooling ring 100 also includes a shoulder 106 and one or more axial openings 108 in the shoulder 106. A first direction 110 may extend through the hollow interior 104 such that the first direction 110 extends along or parallel to the centerline 112 of the cooling ring 100. The axial openings 108 may be substantially aligned with the first direction 110. In some embodiments, the cooling ring 100 may include bevels (not shown in Figure 1) at both ends to create a seal between the cooling ring 100 and other components of the motor housing. The cooling ring 100 is generally hollow and includes a hollow interior 104, which is generally cylindrical and extends through the length of the cooling ring 100. The dimensions and configuration of the hollow interior 104 may be designed to mate with the windings of the motor.

[0033] The location of the axial opening needs to be configured to maintain a desired distance from other surfaces, so that the cooling fluid distribution is directed towards its intended target. For example, the axial opening 108 should generate an oil spray to target the conductive elements and reduce or eliminate oil spray onto other surfaces. The dimensions of the cooling ring 100 can vary depending on the motor configuration.

[0034] Depending on the component requirements, the cooling ring 100 can be formed of plastic or any other material suitable for the desired component.

[0035] Typically, the cooling ring 100 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0036] Figure 2A is a perspective view of the cooling ring 200, Figure 2B is an end view of the cooling ring 200, and Figure 2C is a cross-sectional view of the cooling ring 200. The cooling ring 200 includes an outer surface 202 and a hollow interior 204. The cooling ring 200 also includes a shoulder 206 formed at a first end of a recess 214 and one or more axial openings 208 in the shoulder 206. A first direction 210 may extend through the hollow interior 204 such that the first direction 210 extends along or parallel to the centerline 212 of the cooling ring 200. The axial openings 208 may be substantially aligned with the first direction 210. In some embodiments, the cooling ring 200 may include bevels 216 at both ends to create a seal between the cooling ring 200 and other components of the motor housing. Depending on the motor configuration shown in Figures 2A and 2C, the bevels 216 may be incorporated into the recess 214. Alternatively, the recess 214 may not be limited to a portion of the length of the outer surface 202. The cooling ring 200 is typically hollow and includes a hollow interior 204, which is typically cylindrical and extends through the length of the cooling ring 200. The dimensions and construction of the hollow interior 204 can be designed to fit around the motor windings.

[0037] One or more axial openings 208 can be configured to distribute cooling fluid to the conductive elements. For example, if there are four busbars in the motor assembly, but two of the four busbars generate more heat than the other two, then two axial openings 208 can be positioned to distribute cooling fluid to the two busbars that generate more heat compared to the other two busbars. The size of the cooling ring 100 can vary depending on the motor configuration.

[0038] Depending on the component requirements, the cooling ring 200 can be formed of plastic or any other material suitable for the desired component.

[0039] Typically, the cooling ring 200 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0040] Figure 3A is a perspective view of the cooling ring 300, Figure 3B is an end view of the cooling ring 300, and Figure 3C is a cross-sectional view of the cooling ring 300. The cooling ring 300 includes an outer surface 302 and a hollow interior 304. The cooling ring 300 also includes a shoulder 306 formed at a first end of a recess 314 and one or more axial openings 308 in the shoulder 306. A first direction 310 may extend through the hollow interior 304 such that the first direction 310 extends along or parallel to the centerline 312 of the cooling ring 300. The axial openings 308 may be substantially aligned with the first direction 310. In some embodiments, the cooling ring 300 may include bevels 316 at both ends to create a seal between the cooling ring 300 and other components of the motor housing. The cooling ring 300 is generally hollow and includes a hollow interior 304, which is generally cylindrical and extends through the length of the cooling ring 300. The dimensions and configuration of the hollow interior 304 may be designed to mate with the windings of the motor. The size of the cooling ring 100 can vary depending on the motor configuration.

[0041] Depending on the component requirements, the cooling ring 300 can be formed of plastic or any other material suitable for the desired component.

[0042] Typically, the cooling ring 300 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0043] Figure 4A is a perspective view of the cooling ring 400, Figure 4B is an end view of the cooling ring 400, and Figure 4C is a cross-sectional view of the cooling ring 400. The cooling ring 400 includes an outer surface 402 and a hollow interior 404. The cooling ring 400 also includes a shoulder 406 formed at a first end of a recess 414 and one or more axial openings 408 in the shoulder 406. A first direction 410 may extend through the hollow interior 404 such that the first direction 410 extends along or parallel to the centerline 412 of the cooling ring 400. The axial openings 408 may be substantially aligned with the first direction 410. In some embodiments, the cooling ring 400 may include bevels 416 at both ends to create a seal between the cooling ring 400 and other components of the motor housing. The cooling ring 400 is generally hollow and includes a hollow interior 404, which is generally cylindrical and extends through the length of the cooling ring 400. The dimensions and construction of the hollow 404 stainless steel can be designed to fit around the motor windings.

[0044] One or more axial openings 408 can be configured to distribute cooling fluid to the conductive elements. For example, if there are four busbars in the motor assembly, but two of the four busbars generate more heat than the other two, then two axial openings 408 can be positioned to distribute cooling fluid to the two busbars that generate more heat compared to the other two busbars. The size of the cooling ring 100 can vary depending on the motor configuration.

[0045] Depending on component requirements, the cooling ring 400 can be formed of plastic or any other material suitable for the desired component.

[0046] Typically, the cooling ring 400 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0047] Figure 5A is a perspective view of the cooling ring 500, Figure 5B is an end view of the cooling ring 500, and Figure 5C is a cross-sectional view of the cooling ring 500. The cooling ring 500 includes an outer surface 502 and a hollow interior 504. The cooling ring 500 also includes a shoulder 506 formed at a first end of a recess 514 and one or more axial openings 508 in the shoulder 506. A first direction 510 may extend through the hollow interior 504 such that the first direction 510 extends along or parallel to the centerline 512 of the cooling ring 500. The axial openings 508 may be substantially aligned with the first direction 510. In some embodiments, the cooling ring 500 may include bevels 516 at both ends to create a seal between the cooling ring 500 and other components of the motor housing. The cooling ring 500 is generally hollow and includes a hollow interior 504, which is generally cylindrical and extends through the length of the cooling ring 500. The dimensions and construction of the hollow 504 interior can be designed to fit around the motor windings.

[0048] One or more axial openings 508 can be configured to distribute cooling fluid to the conductive elements. For example, if there are four busbars in the motor assembly, but two of the four busbars generate more heat than the other two, then two axial openings 508 can be positioned to distribute cooling fluid to the two busbars that generate more heat compared to the other two busbars. The size of the cooling ring 100 can vary depending on the motor configuration.

[0049] Depending on component requirements, the cooling ring 500 can be formed of plastic or any other material suitable for the desired component.

[0050] Typically, the cooling ring 500 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0051] Figure 6A is a perspective view of the cooling ring 600, Figure 6B is an end view of the cooling ring 600, and Figure 6C is a cross-sectional view of the cooling ring 600. The cooling ring 600 includes an outer surface 602 and a hollow interior 604. The cooling ring 600 also includes a shoulder 606 formed at a first end of a recess 614 and one or more axial openings 608 in the shoulder 606. A first direction 610 may extend through the hollow interior 604 such that the first direction 610 extends along or parallel to the centerline 612 of the cooling ring 600. The axial openings 608 may be substantially aligned with the first direction 610. In some embodiments, the cooling ring 600 may include bevels 616 at both ends to create a seal between the cooling ring 600 and other components of the motor housing. The cooling ring 600 is generally hollow and includes a hollow interior 604, which is generally cylindrical and extends through the length of the cooling ring 600. The dimensions and configuration of the hollow interior 604 may be designed to mate with the windings of the motor. The size of the cooling ring 100 can vary depending on the motor configuration.

[0052] Depending on the component requirements, the cooling ring 600 can be formed of plastic or any other material suitable for the desired component.

[0053] Typically, the cooling ring 600 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0054] Figure 7A is a perspective view of the cooling ring 700, Figure 7B is an end view of the cooling ring 700, and Figure 7C is a cross-sectional view of the cooling ring 700. The cooling ring 700 includes an outer surface 702 and a hollow interior 704. The cooling ring 700 also includes a shoulder 706 formed at a first end of a recess 714 and one or more axial openings 708 in the shoulder 706. A first direction 710 may extend through the hollow interior 704 such that the first direction 710 extends along or parallel to the centerline 712 of the cooling ring 700. The axial openings 708 may be substantially aligned with the first direction 710. In some embodiments, the cooling ring 700 may include bevels 716 at both ends to create a seal between the cooling ring 700 and other components of the motor housing. The cooling ring 700 is generally hollow and includes a hollow interior 704, which is generally cylindrical and extends through the length of the cooling ring 700. The dimensions and construction of the hollow 704 can be designed to fit around the motor windings.

[0055] One or more axial openings 708 can be configured to distribute cooling fluid to the conductive elements. For example, if there are four busbars in the motor assembly, but two of the four busbars generate more heat than the other two, then two axial openings 708 can be positioned to distribute cooling fluid to the two busbars that generate more heat compared to the other two busbars. The size of the cooling ring 100 can vary depending on the motor configuration.

[0056] Depending on component requirements, the cooling ring 700 can be formed of plastic or any other material suitable for the desired component.

[0057] Typically, the cooling ring 700 is assembled between the housing and the motor, so that it surrounds the motor's conductive elements.

[0058] Figure 8 shows a cross-sectional view of an exemplary assembly 800 including a cooling ring. For example, the cooling ring 200 of Figures 2A-2C. It should be noted that any cooling ring may be included in assembly 800, such as those described with respect to Figures 1A-1C to 7A-7C. Assembly 800 may include a housing 802 to house a motor 808 and the cooling ring 200. Housing 802 may include a coolant reservoir 804. Housing 802 may also include an opening (not shown) allowing coolant to enter a coolant inlet 806 from the coolant reservoir 804. Coolant may be distributed along the side of the motor 808 (such as a stator). Coolant passes from the fluid inlet 806 along the side of the motor 808 to fill a gap 810. Gap 810 may be partially formed by recess 214 and housing 802. Coolant may fill gap 810 such that it has sufficient pressure to pass through the axial opening 208 in shoulder 206 and reach conductive element 812. For example, pressure can generate an oil spray from the axial opening 208 to the conductive element 812. Additionally, the recess 214 may include an opening (not shown) in the radial direction to further distribute the cooling fluid radially to the conductive element 814. Close-up views of Figures 8 and 8A show a flow 820 illustrating the distribution of cooling fluid from the gap 810 toward the conductive element 812 in the axial direction. Furthermore, the assembly 800 may include a seal 816, such as a rubber seal, at one or both ends of the cooling ring 200 to seal the gap 810. The seal 816 may be located between the cooling ring 200 and the housing 802, for example, between the ramp 216 and the housing 802. The seal 816 may be configured to ensure that the gap 810 is tightly sealed, allowing coolant to exit the gap 810 only through the axial opening 208.

[0059] The motor 808 may be configured with one or more external longitudinal cooling fluid channels. Cooling fluid can be transferred from the fluid inlet 806 to the cooling fluid channels. The cooling fluid channels may extend along or adjacent to the stator laminations or along the outer periphery of the stator sub-assemblies. One or more cooling fluid channels are coupled to one or more external longitudinal cooling fluid channels and configured to deliver cooling fluid to the axial opening 208. One or more radial cooling fluid channels may be formed by segmented annular plates disposed between the stator sub-assemblies. Cooling fluid may be discharged from the sub-assemblies in any convenient manner, such as from one or more ends of opposite ends of the stator, and may be cooled and reused.

[0060] Figure 9A shows a simulated graph 900A of the temperature of the conductive elements in the motor assembly during simulated operation at 120-175 km / h. Graph 900A was generated using calculated fluid dynamics simulations.

[0061] Specifically, Figure 900 A compares the operating temperatures of different components of the motor during use. Figure 900 A simulates the operation of the motor without cooling the conductive elements in the axial direction. The Y-axis 902 indicates the operating temperature of several electrical components of the motor in degrees Celsius. The X-axis 904 indicates the operating time of the motor in seconds. As shown in Figure 906, the temperatures of four different conductive elements are plotted over time. For each of the four different conductive elements, the maximum temperature and average temperature are plotted over time. For example, the maximum temperature 908 of the busbar conductive element reaches approximately 145 degrees Celsius after about 700 seconds of operation.

[0062] The cooling ring, combined with the axial opening according to any embodiment disclosed herein, maintains the operating temperature of the conductive element within the desired operating temperature range. In particular, the cooling ring reduces the temperature of the conductive element, which tends to generate the most heat.

[0063] Specifically, Figure 900 B compares the operating temperatures of different components of the motor during use. Figure 900 B simulates the operation of the motor with the conductive elements cooled in the axial direction. The Y-axis 912 indicates the operating temperature of several electrical components of the motor in degrees Celsius. The X-axis 914 indicates the operating time of the motor in seconds. As shown in Figure 916, the temperatures of four different conductive elements are plotted over time. For each of the four different conductive elements, the maximum temperature and average temperature are plotted over time. For example, the maximum temperature 918 of the busbar conductive element reaches approximately 125 degrees Celsius after about 700 seconds of operation.

[0064] Comparing Figures 900A and 900B, it can be seen that the conductive element 906, cooled by a cooling ring without an axial opening, operates at a higher temperature compared to the conductive element 916, which is cooled by a cooling ring with an axial opening, under the same operating conditions. Therefore, the cooling ring with an axial opening to distribute cooling fluid in the axial direction reduces the operating temperature of the motor's conductive elements to the desired operating temperature range.

[0065] While this disclosure has been described with reference to exemplary embodiments, those skilled in the art will understand that various changes can be made and elements can be substituted with equivalents without departing from the scope of this disclosure. Furthermore, many modifications can be made to adapt particular situations or materials to the teachings of this disclosure without departing from the basic scope of this disclosure. Therefore, this disclosure is not intended to be limited to the specific embodiments disclosed, but rather to include all embodiments falling within the scope of the appended claims.

Claims

1. A cooling ring for an electric motor, the cooling ring comprising: A first portion having an outer surface and a hollow interior, the outer surface having a first end and a second end, the hollow interior extending along the longitudinal axis of the cooling ring, wherein the hollow interior is configured to surround the first end of the stator; and a shoulder extending radially outward at the first end of the first portion, wherein the shoulder includes an axial opening extending in a first direction, wherein the first direction is substantially parallel to the longitudinal axis of the cooling ring.

2. The cooling ring according to claim 1, wherein, The first portion forms one or more radially inward recesses at the first end that are spaced apart from at least a portion of the circumference of the first portion.

3. The cooling ring according to claim 2, wherein, Each of the one or more recesses includes a shoulder extending radially outward at the first end of the first portion and the axial opening.

4. The cooling ring according to any one of the preceding claims, wherein, The cooling ring is disposed between the housing and the first end of the stator, wherein the position of the cooling ring creates a gap between the housing and the outer surface of the cooling ring.

5. The cooling ring according to any one of the preceding claims, wherein, The axial opening is axially oriented toward the first conductive element, wherein the first conductive element is substantially in the first direction relative to the axial opening.

6. The cooling ring according to claim 5, wherein, The first conductive element is a busbar.

7. The cooling ring according to claim 5, wherein, The first conductive element is a winding.

8. The cooling ring according to claim 5, wherein, The first conductive element is an I-type pin.

9. The cooling ring according to any one of claims 4-8, wherein, The gap, including the recess, is configured to be filled with cooling fluid.

10. The cooling ring according to any one of the preceding claims further includes a radial opening extending in a second direction, wherein, The second direction is substantially perpendicular to the first direction, and the cooling fluid passes through the radial opening substantially in the second direction.

11. The cooling ring according to claim 10, wherein, A radial opening is located radially facing the second conductive element.

12. The cooling ring according to claim 11, wherein, The second conductive element is located at the first end of the stator.

13. The cooling ring according to claim 11 or 12, wherein, The second conductive element is the stator winding and / or the stator's type I pin.

14. The cooling ring according to any one of the preceding claims, wherein, The cooling ring is made of plastic.

15. A stator cooling assembly for an electric motor, the stator assembly comprising: A housing including a cooling fluid reservoir and a hollow opening, wherein the cooling fluid reservoir includes a fluid opening extending radially inward from the cooling fluid reservoir to the hollow opening; a stator including a core and a first conductive element extending axially from the core, wherein the core includes a cooling fluid channel, and wherein the fluid channel is positioned aligned with the fluid opening of the housing; and a cooling ring including: a first portion having an outer surface and a hollow interior, the outer surface having a first end and a second end, the hollow interior extending along a longitudinal axis of the cooling ring, wherein the hollow interior is configured to surround the first conductive element of the stator. A shoulder extending radially outward at the first end of the first portion, wherein the shoulder includes an axial opening extending along a first direction, wherein the first direction is substantially parallel to the longitudinal axis of the cooling ring, wherein the cooling ring is positioned in the hollow opening of the housing such that the second end is adjacent to the core, and a gap is formed between the inner surface of the housing and the outer surface of the cooling ring, and the axial opening faces the second conductive element, and wherein the stator cooling assembly is configured to dispense cooling fluid from the cooling fluid reservoir through the cooling fluid channel to fill the gap, and to further dispense the cooling fluid to the second conductive element through the axial opening.

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