Compression seal for stator cooling

Abstract

Arrangement, comprehensive: a stator core; a case; a sleeve that is arranged and compressed between the stator core and the housing, wherein the sleeve comprises an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts a side of the stator core.

Description

CROSS-REFERENCE TO RELATED REGISTRATIONS

[0001] The present application claims priority over US Preliminary Application No. 63 / 740,637 entitled “COMPRESSION SEALING FOR STATOR COOLING”, which was filed on December 31, 2024. TECHNICAL AREA

[0002] The present disclosure relates to cooling systems for electric motor stator cooling systems. BACKGROUND AND DETOUR

[0003] A stator is a stationary component found in electric motors and generators. A stator can consist of a laminated core and coils of insulated wire, called stator windings. When an alternating current is applied to a stator, it can generate a rotating magnetic field. Stators are the stationary part of a rotating system found in electric generators, electric motors, sirens, mud motors, and similar devices. Energy can flow through a stator to or from a rotating component of the system, the rotor. In an electric motor, a stator can generate a magnetic field that drives a rotating armature. In a generator, a stator can convert a rotating magnetic field into an electric current. In fluid-driven devices, a stator can conduct a fluid flow to or from a rotating part of the system.Stators can be used, for example, in electric motors of electric vehicles (EVs) and hybrid electric vehicles (HEVs).

[0004] The inventors have recognized that in motor applications in electric vehicles (EVs) and hybrid electric vehicles (HEVs), cooling the stator winding can increase motor efficiency. For example, cooling performance targets can, in some cases, utilize oil flow across the stator to cool motor components. However, the inventors have realized that in some cooling system designs, oil or other coolants can be routed through internal cavities, from which the fluid can escape into an air gap between the rotor and stator. Oil in the air gap can lead to resistance losses, which in turn can, for example, result in a significant reduction in motor efficiency.

[0005] To solve these and other problems, an exemplary approach provides an arrangement comprising a stator core, a housing, and a sleeve that is positioned and compressed between the stator core and the housing, wherein the sleeve includes an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts one side of the stator core.

[0006] Such an approach can simplify the sealing system to reduce potential failure modes and increase cooling system efficiency. Furthermore, it can provide a substantially constant axial force to press the sleeve onto the stator core over a wide temperature range and manufacturing tolerances. For example, compression sleeves can be fitted to each side of a stator core and compressed by a wave spring or other suitable spring between the sleeve and the housing at each end of the stator core, creating a sealed stator cavity.

[0007] It should be noted that the foregoing summary serves to present, in simplified form, a selection of concepts that are further explained in the detailed description. It does not serve to identify essential features of the claimed subject matter, the scope of which is defined exclusively by the claims following the detailed description. Furthermore, the claimed subject matter is not limited to implementations that eliminate the disadvantages mentioned above or in any part of this disclosure. BRIEF DESCRIPTION OF THE FIGURES Fig. Figure 1 shows an electric motor with a rotor arrangement comprising a rotor core and a rotor shaft according to the present disclosure. Fig. Figure 2 shows a perspective cross-sectional view of a cooling system for an electric motor according to the disclosure. The Fig. Figures 3-5 show cross-sectional views of an interface between an exemplary compression sleeve and a stator core according to the disclosure. Fig. Figure 6 shows an example of a motor system with guide vanes for directing coolant between stator windings. DETAILED DESCRIPTION

[0008] The following description refers to systems for cooling components of an electric motor using compression sleeves arranged along a stator core to guide a suitable coolant, such as oil or another suitable dielectric fluid, around the stator and stator windings.

[0009] As mentioned above, the inventors recognized that in motor applications in electric vehicles (EVs) and hybrid electric vehicles (HEVs), cooling the stator winding can increase motor efficiency. For example, cooling performance targets can, in some cases, utilize oil flow across the stator to cool motor components. However, the inventors recognized that in some cooling system designs, oil or other coolants can be routed through internal cavities, from which the fluid can escape into an air gap between the rotor and stator. Oil in the air gap can lead to resistance losses, which in turn can result in, for example, a significant reduction in motor efficiency.

[0010] In particular, the inventors recognized that sealing a stator for immersion cooling can be desirable to prevent the flowing dielectric coolant from entering the rotor cavity and causing undesirable turbulence losses. In EV motor applications, cooling the stator windings can be used to maintain the desired power and efficiency, for example, by increasing the power and torque density. In some examples, a flow of dielectric fluid, such as oil or another suitable fluid, across the stator can be used to achieve power and torque targets. To achieve this, the stator can be essentially sealed, as described here, so that the flowing dielectric coolant cannot, for example, enter the rotor cavity and cause undesirable turbulence losses.

[0011] To solve these and other problems, an arrangement is provided in an exemplary approach described in more detail below, comprising a stator core, a housing and a compressed sleeve arranged between the stator core and the housing, wherein the sleeve includes an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts one side of the stator core.

[0012] Such an approach can simplify the sealing system to reduce potential failure modes and increase cooling system efficiency. Furthermore, in some examples, this approach can eliminate the need for adhesives at the interfaces between the compression sleeves and the stator. Additionally, such an approach can provide a substantially constant axial force to press the sleeve onto the stator core over a wide temperature range and manufacturing tolerances. For example, in such an approach, compression sleeves can be mounted on each side of a stator core and compressed by a wave spring or other suitable spring between the sleeve and the housing at each end of the stator core, creating a sealed stator cavity.

[0013] In the approaches described here, the sleeve seal support and the seal assembly can be designed to create an initial seal compression in the "assembled" state, sufficient to maintain the seal of the stator cavity. Furthermore, a hard stop for the seal support can prevent significant deformation of the seal above the support, thus reducing the leakage of sealant into the rotor cavity. This same design feature can cause the seal to deform under coolant pressure, increasing the seal pressure against the stator core and maximizing sealing performance over a range of operating pressures.

[0014] In some examples, the approaches described here can be used in combination with other cooling approaches and systems. For example, the approaches described here can be combined with a conventional water and / or ethylene glycol (WEG) cooling jacket to maximize cooling in motors with longer effective lengths.

[0015] It is understood that the specific arrangements and systems illustrated in the accompanying drawings and described in the following description are examples of embodiments of the inventive concepts defined herein. For the purposes of discussion, the drawings are described together. Therefore, identical elements may be designated by the same reference numerals and need not be introduced again.

[0016] Regarding the illustrations, Fig. Figure 1 shows a representation of an electric motor 100. In some examples, the electric motor 100 can be designed as an electric motor-generator and be included in a system 102, which can take various forms. For example, the electric motor 100 can be integrated into an electric drive system of an electric vehicle (EV). In such an example, the electric motor can be a traction motor, and the electric drive can additionally include a transmission (e.g., a manual transmission). In the EV example, the EV can be a fully electric vehicle (e.g., a battery electric vehicle (BEV)) in one example, or a hybrid electric vehicle (HEV) with an internal combustion engine in another. However, the motor can also be used in other suitable systems (e.g., stationary systems), such as industrial machinery, agricultural systems, mining systems, and the like.

[0017] The electric motor 100 comprises a rotor 104 that interacts electromagnetically with a stator 106 to drive the rotation of a rotor shaft 108 contained within the rotor. In the illustrated example, the electric motor 100 includes a housing 110 with an electrical interface 112 for the stator 106. The electrical interface 112 can be a multi-phase electrical interface with multiple electrical terminals 114. The electrical interface 112 is shown as a three-phase interface in the illustrated example; however, it is understood that any suitable interface is acceptable, such as a two-phase, four-phase, six-phase, nine-phase, etc. More generally, the electric motor 100 can be a multi-phase alternating current (AC) machine. In other examples, however, the electric motor 100 can also be a direct current (DC) machine.

[0018] As in Fig. As shown in Figure 1, the electric motor 100 can be electrically coupled to an inverter 116. The inverter 116 can be configured to convert direct current (DC) to alternating current (AC). Alternatively, the inverter 116 can be configured to convert AC to DC. Thus, the electric motor 100 can be an AC electric motor, as shown above. In other examples, however, the electric motor 100 can be a DC motor (as shown previously), and the inverter 116 can therefore be omitted from the system 102. The inverter 116 can receive electrical energy from one or more energy storage devices 118 (e.g., traction batteries, capacitors, combinations thereof, and the like). The arrows 120 indicate the electrical energy transfer between the electric motor 100, the inverter 116, and the energy storage device(s) 118, which can occur in the various operating modes of the system.

[0019] System 102 can additionally include a control subsystem 180 with a control unit 182. The control unit 182 comprises a processor 184 and memory 186. Instructions can be stored in memory 186 which, when executed by the processor 184, cause the control unit 182 to perform the various procedures, control techniques, and the like described herein. The processor 184 can contain a microprocessor unit and / or other types of circuitry. Memory 186 can comprise known data storage media, such as random access memory, read-only memory, keep-alive memory, combinations thereof, and the like.

[0020] The control unit 182 can receive various signals from sensors 188 located at different positions within the system 102. These sensors 188 can include an electric motor speed sensor, temperature sensors for energy storage devices, one or more state-of-charge sensors for energy storage devices, an inverter power sensor, and the like. The control unit 182 can also send control signals to various actuators 190 located at different points within the system 102. For example, the control unit can send signals to the inverter 116 to adjust the speed of the electric motor 100. In another example, the control unit 182 can send a command signal to the electric motor 100 and / or the inverter 116, which then adjusts the motor speed. The other controllable components of the system 102 can function similarly with respect to the command signals and the actuator settings.

[0021] The system 102 may also include one or more input device(s) 192 (e.g., an accelerator pedal, a brake pedal, a console instrument panel, a touch interface, a touch panel, a keyboard, combinations thereof, and the like). The input device(s) 192 may, in response to user input, generate a request to adjust the engine speed.

[0022] The figures show an axis system 150 for illustrative purposes. In one example, the z-axis can be a vertical axis (e.g., parallel to a gravitational axis), the x-axis can be a lateral axis (e.g., a horizontal axis), and / or the y-axis can be a longitudinal axis. In other examples, however, the axes can have other orientations. The axis of rotation 199 of the electric motor 100 is shown for illustration in Fig. 1 additionally shown. A sectioning plane 2-2 for the in Fig. The cross-sectional view shown in Figure 2 is in Fig. Figure 1 shows the section plane 2-2 passing through the axis of rotation of the motor.

[0023] Fig. Figure 2 shows a perspective cross-sectional view of the electric motor 100 and the cooling system 200 for the motor. Fig. Figure 2 shows the stator 106 of the electric motor 100 and part of the housing 110, which at least partially encloses the rotor and the stator.

[0024] Fig. Figure 2 shows an arrangement 280 that can be used to cool at least some components of the electric motor 100. The arrangement 280 can, for example, comprise an electric motor system. In some examples, the arrangement shown in Figure 2 can be used to cool the electric motor system. Fig. The arrangement 280 shown in Figure 2 can be used to cool components of an electric motor in an electric or hybrid electric vehicle. However, it is intended that the arrangement 280 can be used to cool any suitable rotor / stator system.

[0025] The arrangement 280 comprises a stator 106 with a stator core 282. The stator core can, for example, be a hollow opening within the stator configured to receive and contain a rotor. The stator and the stator core can include laminations, meaning they can be formed from multiple layers of metal of varying thicknesses laminated together. A lamination can, for example, contain thin metal sheets that are typically joined, welded, or stacked together to form multiple durable layers. Laminations can be provided at different locations within the stator in varying thicknesses and reduce eddy current losses, for example, by using several individual pieces of metal instead of a single solid piece of metal.

[0026] The arrangement 280 further comprises a housing 110. The housing 110 can, in one example, be formed from various sections that are connected to one another. For instance, a crown-side section 208 and a weld-side section 210 can be connected to a housing body 290. The housing 290 can fully enclose the stator 106 and other components and features of the cooling system 200 described herein. Fasteners and / or other suitable fastening devices can be used to secure the crown-side section 208 and / or the weld-side section 210 to the housing body 290.

[0027] The arrangement 280 further comprises at least one sleeve (e.g., sleeve 204 or sleeve 206) which is arranged and compressed between the stator core 282 and the housing 110. In some examples, as in Fig. As shown in Figure 2, the arrangement 280 can comprise a first compression sleeve 204, which is compressed between a first side (e.g., crown-side) 208 of the housing 110 and a first side 284 of the stator core 282, and a second compression sleeve 206, which is compressed between a second side (e.g., weld-side) 210 of the housing 110 and a second side 286 of the stator core 282. The second side 286 of the stator core 282 can be opposite the first side 284 of the stator core 282, i.e., the second side 286 can be located on a side of the stator core 282 opposite the first side 284.

[0028] Each sleeve can form a cavity between the stator core and the housing, the cavity being essentially fluidically sealed from a rotor cavity in the stator core. As used here, the term "fluidically sealed" means that essentially no fluid can escape from the cavity and enter the rotor cavity, so that the cavity is a space essentially separate from the rotor cavity. As, for example, in Fig. As shown in Figure 2, the housing 110 comprises an inner radial surface 214, an outer radial surface 212, and an end surface 216, all arranged on the first side 284 of the stator core 282, such that, in combination with the compression sleeve 204, they form a cavity 218 through which coolant can flow. Likewise, the housing 110 comprises an inner radial surface 222, an outer radial surface 224, and an end surface 226, all arranged on the second side 286 of the stator core 282, and such that, in combination with the compression sleeve 206, they form a cavity 228 through which coolant can flow.

[0029] The cavities formed by the compression sleeve can also contain stator windings (in Fig. 2 not shown). For example, the one in Fig. The cavity 218 shown encloses the stator windings at 220, so that the stator windings are arranged in the cavity. In this way, as the coolant flows through the cavity, it can lower the temperature of the end windings during operation.

[0030] The cooling system 200 can further include various inlets and outlets to guide a coolant, e.g., a dielectric fluid such as oil or the like, through the channels / cavities in the cooling system. For example, in Fig. Figure 2 shows an inlet 230. The cooling system 200 can include a pump (not shown) and a filter (not shown) for supplying a coolant, e.g., an oil such as a natural and / or synthetic oil and / or another suitable dielectric fluid, to or around components of the stator 106. The sealed cavities formed by the compression sleeves (e.g., sleeves 204 and 206), e.g., cavities 218 and 228, can receive and / or discharge coolant around components of the stator core 282. The sealed cavities 218 and 228 can be fluidically separated from the rotor cavity 227 (in which the rotor is contained and configured for rotation). In this way, it can be largely prevented from coolant entering an air gap in the rotor cavity, thus reducing, for example, the resistance losses in the motor and thereby increasing its efficiency.

[0031] The sleeves (e.g., sleeve 204 and sleeve 206) can be compressed between the stator core 282 and the housing 110 by a spring arranged along an outer diameter of the sleeve opposite an elastomeric seal located at an edge of the sleeve at an interface between the sleeve and the stator core. In some examples, the spring can be arranged opposite a face of the elastomeric seal, as the spring can be located at any point on the sleeve, provided it has features that allow a compressive force to be exerted on the seal. In particular, sleeve 204, as shown in Fig. Figure 2 shows an elastomeric seal at an interface 244 between the sleeve 204 and the first side 284 of the stator core 282, and a spring 240 may be arranged on an edge of the sleeve 204 opposite the edge of the sleeve 204 where the seal is located at the interface 244; and the sleeve 206 comprises an elastomeric seal at an interface 226 between the sleeve 206 and the second side 286 of the stator core 282, and a spring 242 may be arranged on an edge of the sleeve 206 opposite the edge of the sleeve 206 where the seal is located at the interface 246. The elastomeric seals at the interfaces 244 and 246 are referred to below with reference to the Fig. 3-5 explained and described in more detail.

[0032] The springs, e.g., springs 240 and 242, may in some examples include wave springs or the like. In other examples, the springs may include disc springs or the like. Wave springs, also known as coiled wave springs or scrowave springs, are springs manufactured from pre-hardened flat wire in a process called on-edge coiling (also known as edge winding). The number of turns and waves can be adjusted to withstand greater forces or to achieve specific target spring forces. The wave springs that can be used to compress the sleeves may include single-turn wave springs, multi-turn wave springs, nested wave springs, or the like.

[0033] As mentioned above, the springs that compress the sleeves can, in other examples, include disc springs, also known as conical spring washers, tapered spring washers, or Belleville washers. A Belleville washer is a type of spring in the shape of a pressure plate and can be used in some applications to compress one or more sleeves in the cooling system. Other types of springs can be used to generate a compressive force. For example, suitable preload spring mechanisms such as an oil-operated preload spring or a spring built into the sleeve.

[0034] In some examples, the springs that compress the sleeves, e.g., wave springs, can have a nominal compressive force of approximately 467 N (approx. 110 lbf) or be in the range of approximately 400 to 500 N. However, other compressive forces are also conceivable.

[0035] The compression sleeves can have an angled shape to fit between the housing and the stator core. For example, the first compression sleeve 204 can have a first bend 232 and a second bend 234, with the second bend 234 located on the stator side of the sleeve 204. Similarly, the second compression sleeve 206 can have a first bend 238 and a second bend 236, with the second bend 236 located on the stator side of the sleeve 206. The bends in the sleeves can extend radially around the sleeve and be configured such that the housing side of the sleeves is lower (along the z-axis) than the stator side of the sleeve.

[0036] These springs, which compress the sleeves, can generate a substantially constant axial force to press the sleeve onto the stator core over a wide temperature range and manufacturing tolerances. In such an approach, for example, compression sleeves can be fitted to each side of a stator core and compressed by a wave spring or other suitable spring between the sleeve and the housing at each end of the stator core, creating a sealed stator cavity. The support function of the sleeve seal and the seal design can be configured to provide an initial seal compression in the assembled state, sufficient to maintain the seal of the stator cavity.Furthermore, a hard stop device for the seal support (described in more detail below) can prevent significant deformation of the seal above the support and reduce the leakage of sealant into the rotor cavity. This same design feature can cause the seal to deform under coolant pressure, increasing the seal's pressure on the stator core and thus maximizing sealing performance over an operating pressure range.

[0037] The Fig. Figures 3-5 show detailed cross-sectional views of an interface, e.g., interface 244, between an exemplary compression sleeve 204 and a stator core 282. As mentioned above, each sleeve, e.g., sleeves 204 and 206, can include an elastomeric seal arranged along an outer diameter of the sleeve at an edge of the sleeve on the stator side. For example, sleeve 204, as shown in the Fig. Figures 3-5 show an elastomeric seal 302 pressing against a side 284 of the stator core 282.

[0038] In some examples, the sleeve 204 may have a groove 332 along an outer diameter of the sleeve (on the stator side of the sleeve), and the elastomer seal 302 may be arranged in the groove. In some embodiments, the seal 302 may be formed as an integral part of the sleeve. In other examples, however, the seal 302 may be inserted into and held in the groove 332 by an interference fit, an adhesive, or the like.

[0039] The elastomer seal can include a lip 306 that abuts one side of the stator core. Specifically, the seal 302 can have a thicker end 304 and a thinner end 306 with a tip that fits into a sealing lip support recess 308 in the stator core 282, which is configured to receive and secure one end of the lip. As mentioned above, the stator core contains laminations, and the laminations on the stator core around the sealing lip recess 308 can have a thickness in the range of about 0.5 mm to 2 mm, although other thicknesses are conceivable. In some examples, the stator core lamination can have a hybrid lamination structure that optimizes the sealing contact area between the stator core 282 and the seal 302. For example, as in Fig. Figure 5 shows that an area 502 near the seal 302 on the sleeve has thicker laminations than an area 504 of the stator core 282, which is located above the stator cavity 244.

[0040] The 302 gasket can be made from any suitable material and, in some examples, exhibits an elongation of approximately 3% in the assembled state and a nominal compression of 10% through the sealing lip. The gasket material can be selected to achieve the desired compression force, process, fluid compatibility, and application temperature to meet specified objectives. Examples of materials that can be used include HNBR, NBR, Viton, Nytrill, ACM, etc.

[0041] In some examples, guide vanes may be provided that surround the stator windings in a cavity formed by the sleeve between the stator core and the casing. Such guide vanes may be configured to direct the flow of a dielectric fluid between the stator windings within the cavity. In some examples, the sealing sleeve may be configured to include a guide vane surrounding the heads to force oil flow between the vanes and maximize the cooling performance of the center guide vanes.

[0042] For example, it shows Fig. Figure 6 shows an example of a motor system 600 with guide vanes 602 for guiding coolant between stator windings. In particular, Figure 6 shows Fig. Figure 6 shows a crown-side view of the electric motor 100 and the cooling system 200, with the sealing sleeve omitted to reveal the guide vanes 602 around the stator windings. In the example shown, guide vanes 402 with intervening channels 404 are arranged around the stator windings. The guide vanes can be part of the sleeve or configured as a separate structure. If configured as a separate structure, they can be attached to the compression sleeve by mechanical and / or chemical fastening techniques such as welding (e.g., vibration welding, laser welding, and the like), one-piece casting, bonding, combinations thereof, and the like.

[0043] The guide vanes 602 can be contoured so that the channels 604 allow coolant to flow from the coolant cavity, e.g., the one in Fig. The cavity 218 shown in Figure 2 can receive the coolant and guide it to and through the stator's end windings. This allows for more effective cooling of the end windings. The guide vanes 602 are also profiled to allow the end windings to pass through them. The guide vanes 602 can be radially oriented and / or arranged symmetrically around the ring at predetermined angles. The channels 604 between the guide vanes 602 extend radially and are oriented towards the stator so that the coolant can flow through the channels 604 and be directed to the end windings. In one example, the channels 604 can have a rectangular cross-section. However, other channel profiles are also considered.

[0044] Apart from the schematically depicted components, Fig.Figures 1-6 are drawn approximately to scale. In other embodiments, however, the components may have different relative dimensions. The figures show example configurations with the relative arrangement of the various components. If these elements are in direct contact with each other or directly coupled, they can be described as being in direct contact or directly coupled, at least in one example. Similarly, elements shown side by side or adjacent to each other can be described as being adjacent to each other or adjacent to each other, at least in one example. For instance, components that are in planar contact with each other can be described as being in planar contact. As another example, elements that are separated from each other only by a gap and have no other components can be described as such in at least one example.In yet another example, elements that are depicted above / below each other, on opposite sides, or to the left / right of each other can be described as such, relative to one another. Furthermore, in at least one example, as shown in the figures, a topmost element or the highest point of an element can be described as a "top" of the component, and a bottommost element or the lowest point of the element can be described as a "bottom" of the component. The terms top / bottom, upper / lower, above / below used here can refer to a vertical axis of the figures and be used to describe the arrangement of elements in the figures relative to one another. Thus, in one example, elements that are shown above other elements are arranged vertically above the other elements. As another example, the shapes of the elements depicted in the figures can be described as such (e.g., shapes, shapes, and forms).B. circular, straight, flat, curved, rounded, beveled, angled, and the like). Furthermore, in one example, elements that are coaxial with each other can be designated as such. Additionally, the depicted elements that intersect each other can be designated as intersecting elements or mutually intersecting elements in at least one example. Furthermore, an element that is depicted inside or outside another element can be designated as such. In other examples, elements that are offset from each other can be designated as such. Additionally, elements that are coaxial or parallel to each other can be designated as such.

[0045] The invention is described in more detail in the following paragraphs. In one embodiment, an arrangement is provided comprising a stator core, a housing, and a sleeve that is arranged and compressed between the stator core and the housing. The sleeve includes an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts one side of the stator core. In some examples, the sleeve may have a groove along an outer diameter of the sleeve, with the elastomeric seal arranged in the groove. In another aspect, the stator core may include a sealing lip support recess configured to receive and secure one end of the lip.In some examples, the stator core may include laminations, and laminations on the stator core around the sealing lip recess may, for example, have a minimum thickness in the range of approximately 0.5 mm to 2 mm. In some aspects, the sleeve may comprise a first sleeve compressed between a first side of the housing and a first side of the stator core, and a second sleeve compressed between a second side of the housing and a second side of the stator core. In some examples, the second side of the stator core may face the first side of the stator core.In some aspects, the first sleeve may include a first elastomeric seal arranged along an outer diameter of the first sleeve, the first elastomeric seal comprising a first lip abutting the first side of the stator core; and the second sleeve may include a second elastomeric seal arranged along an outer diameter of the second sleeve, the second elastomeric seal comprising a second lip abutting the second side of the stator core. In some examples, the sleeve may form a cavity between the stator core and the housing, the cavity being essentially fluidically sealed from a rotor cavity in the stator core. In some examples, an inlet and outlet may be included in the cavity and configured to guide a dielectric fluid through the cavity. In some examples, stator windings may be arranged in the cavity.In some aspects, the sleeve between the stator core and the housing can be compressed by a spring arranged along an outer diameter of the sleeve opposite the elastomer seal. In some examples, the spring may comprise a wave spring or the like. In other examples, the springs may comprise a disc spring or the like. In some aspects, guide vanes surrounding the stator windings may be contained within a cavity formed by the sleeve between the stator core and the housing, the guide vanes being configured to direct the flow of a dielectric fluid between the stator windings within the cavity.

[0046] In another aspect, a cooling system for an electric motor is provided, comprising: a stator core; a housing; a sleeve positioned and compressed between the stator core and the housing, the sleeve comprising an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts one side of the stator core; and the sleeve being compressed between the stator core and the housing by a spring arranged along an outer diameter of the sleeve opposite the elastomeric seal. In some examples, the stator core may include a sealing lip support recess configured to receive and secure one end of the lip; and the laminations on the stator core around the sealing lip recess having a minimum thickness in the range of approximately 0.5 mm to 2 mm.In some examples, the sleeve can form a cavity between the stator core and the housing, wherein the cavity is essentially fluidically sealed from a rotor cavity in the stator core; and wherein the cooling system for the electric motor further comprises an inlet and an outlet in the cavity which are configured to guide a dielectric fluid through the cavity, with stator windings arranged in the cavity.

[0047] In another aspect, an electric motor cooling system for an electric or hybrid electric vehicle is provided, comprising a stator core, a housing, a first sleeve compressed between a first side of the housing and a first side of the stator core, and a second sleeve compressed between a second side of the housing and a second side of the stator core, the second side of the stator core being opposite the first side of the stator core; wherein the first sleeve comprises a first elastomeric seal arranged along an outer diameter of the first sleeve, the first elastomeric seal comprising a first lip abutting the first side of the stator core; and wherein the second sleeve comprises a second elastomeric seal arranged along an outer diameter of the second sleeve, the second elastomeric seal comprising a second lip abutting the second side of the stator core.In some examples, the first sleeve between the first side of the stator core and the first side of the housing can be compressed by a first spring arranged along an outer diameter of the first sleeve opposite the first elastomeric seal; and the second sleeve between the second side of the stator core and the second side of the housing can be compressed by a second spring arranged along an outer diameter of the second sleeve opposite the second elastomeric seal. In some examples, the first and second springs can be wave springs.

[0048] Although various embodiments have been described above, it should be understood that these are to be considered examples and not limitations. Those skilled in the art will recognize that the disclosed subject matter can be implemented in other specific forms without deviating from the spirit of the subject matter. The embodiments described above are therefore to be regarded in every respect as illustrative and not as limiting. Thus, the configurations and routines disclosed here are exemplary in nature, and the specific examples are not to be considered limiting, since numerous variations are possible. The subject matter of this disclosure includes all novel and non-obvious combinations and sub-combinations of the various systems and configurations, as well as other features, functions, and / or properties disclosed herein.

[0049] The following claims highlight in particular certain combinations and subcombinations that are to be considered novel and not obvious. These claims may refer to "one" element or "a first" element, or the equivalent thereof. Such claims are to be understood as including one or more such elements, with two or more such elements neither required nor excluded. Other combinations and subcombinations of the disclosed features, functions, elements, and / or properties may be claimed by amending the present claims or by filing new claims in this or a related application. Such claims, whether they have a broader, narrower, the same, or different scope than the original claims, are also to be considered as included in the subject matter of the present disclosure. QUOTES INCLUDED IN THE DESCRIPTION

[0000] This list of documents cited by the applicant was automatically generated and is included solely for the reader's convenience. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions. Cited patent literature

[0000] US 63 / 740,637

[0001]

Claims

[1] Arrangement, comprehensive: a stator core; a case; a sleeve that is arranged and compressed between the stator core and the housing, wherein the sleeve comprises an elastomeric seal arranged along an outer diameter of the sleeve, the elastomeric seal comprising a lip that abuts a side of the stator core. [2] Arrangement according to claim 1, wherein the sleeve has a groove along an outer diameter of the sleeve; and wherein the elastomeric seal is arranged in the groove. [3] Arrangement according to one of the preceding claims, wherein the stator core comprises a sealing lip support recess configured to receive and secure one end of the lip. [4] Arrangement according to claim 3, wherein the stator core comprises laminations and the laminations on the stator core around the sealing lip recess have a minimum thickness in the range of about 0.5 mm to 2 mm. [5] Arrangement according to one of the preceding claims, wherein the sleeve comprises a first sleeve which is compressed between a first side of the housing and a first side of the stator core, and a second sleeve which is compressed between a second side of the housing and a second side of the stator core. [6] Arrangement according to claim 5, wherein the second side of the stator core is opposite the first side of the stator core. [7] Arrangement according to claim 5 or 6, wherein the first sleeve comprises a first elastomeric seal arranged along an outer diameter of the first sleeve, wherein the first elastomeric seal comprises a first lip abutting the first side of the stator core; and wherein the second sleeve comprises a second elastomeric seal arranged along an outer diameter of the second sleeve, wherein the second elastomeric seal comprises a second lip abutting the second side of the stator core. [8] Arrangement according to one of the preceding claims, wherein the sleeve forms a cavity between the stator core and the housing, wherein the cavity is substantially fluidically sealed from a rotor cavity in the stator core. [9] Arrangement according to claim 8, further comprising an inlet and an outlet in the cavity, which are configured to guide a dielectric fluid through the cavity. [10] Arrangement according to claim 8 or 9, wherein stator windings are arranged in the cavity. [11] Arrangement according to one of the preceding claims, wherein the sleeve between the stator core and the housing is compressed by a spring which is arranged opposite a surface of the elastomer seal. [12] Arrangement according to claim 11, wherein the spring comprises a wave spring. [13] Arrangement according to claim 11 or 12, wherein the spring comprises a disc spring. [14] Arrangement according to one of the preceding claims, further comprising guide plates surrounding stator windings in a cavity formed by the sleeve between the stator core and the housing, wherein the guide plates are arranged to direct the flow of a dielectric fluid between the stator windings in the cavity. [15] Electric motor cooling system for an electric or hybrid electric vehicle, comprising: a stator core; a case; a first sleeve compressed between a first side of the housing and a first side of the stator core, and a second sleeve compressed between a second side of the housing and a second side of the stator core, the second side of the stator core being opposite the first side of the stator core; wherein the first sleeve comprises a first elastomeric seal arranged along an outer diameter of the first sleeve, wherein the first elastomeric seal comprises a first lip abutting the first side of the stator core; and wherein the second sleeve comprises a second elastomeric seal arranged along an outer diameter of the second sleeve, wherein the second elastomeric seal comprises a second lip abutting the second side of the stator core.

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