Lubricant supply system and method for lubricant-supported electric motors

Abstract

A lubricant supply system for electric vehicles includes a lubricant-supported electric motor and a lubricant supply line extending from a high-voltage source to the lubricant-supported electric motor for supplying lubricant to the lubricant-supported electric motor. In one configuration, at least one powertrain component is configured to be in fluid communication with the lubricant supply line and in fluid parallel with the lubricant-supported electric motor for supplying lubricant to said at least one powertrain component. In an alternative configuration, the powertrain component is in fluid series with the lubricant-supported electric motor and is located downstream therefrom for supplying lubricant from the lubricant-supported electric motor to the powertrain component. In either configuration, the lubricant-supported electric motor is incorporated into the vehicle's existing lubricant supply system to reduce cost and complexity relative to existing designs of lubricant-supported electric motors that require a dedicated lubricant supply for the lubricant-supported electric motor.

Description

[0001] Cross-references to related applications

[0002] This application claims priority to U.S. Provisional Patent Application Serial No. 62 / 905,474, filed September 25, 2019, the entire disclosure of which is incorporated herein by reference. Technical Field

[0003] This disclosure generally relates to lubricated electric motors. More specifically, this disclosure relates to lubricant supply systems and methods for supplying lubricant to lubricated electric motors and other components of associated electric or hybrid electric vehicles. Background Technology

[0004] This section provides background information relating to lubricant-supported electric motors, and this section is not necessarily prior art to the inventive concept disclosed and claimed in this application.

[0005] Various powertrain systems in cars, trucks, and certain off-highway applications draw power from a central prime mover and distribute it to the wheels using mechanical devices such as transmissions, differentials, driveshafts, and drive shafts. These configurations work well when the prime mover can be large or bulky, such as various internal combustion engines (ICEs). However, more attention has turned to alternative prime mover setups that offer improved environmental performance, eliminate mechanical drivetrain components, and result in lighter vehicles with more passenger and payload space.

[0006] "On-wheel" motor configurations are an alternative setup to conventional ICE prime movers, distributing prime mover functionality to each or some of the multiple wheels via one or more electric motors located near, on, or within the wheels. For example, in one instance, a traction motor supporting the rotor via a central shaft passing through the rotor and rolling element bearings can be used as an "on-wheel" motor configuration. In another instance, a lubricated electric motor, such as that described in U.S. Application Serial No. 16 / 144,002 (the disclosure of which is incorporated herein by reference), can be used as an "on-wheel" motor configuration. While each "on-wheel" motor configuration in these configurations is smaller and lighter than an internal combustion engine-based prime mover, they each have certain disadvantages and drawbacks.

[0007] For example, when a lubricated motor is used in an electric or hybrid electric powertrain system, in existing setups, a separate lubricant supply system is required for the motor, resulting in additional costs and a more complex lubrication system to support the integration of the lubricated motor. Furthermore, previous setups for lubricated motors were not controlled in real time, but rather based on statically selected parameters that did not optimize the motor's performance. Therefore, there remains a need for continuous improvement of lubricated motors to enhance performance across a wide speed range encountered in wheel-end prime mover applications, which also reduces implementation costs and provides a smaller footprint in electric or hybrid electric powertrain systems. Summary of the Invention

[0008] This section provides a general overview of the inventive concepts related to this disclosure and is not intended to be interpreted as a complete and comprehensive list of all its aspects, objectives, features and advantages.

[0009] A lubricant supply system for an electric or hybrid electric vehicle includes a lubricant-supported electric motor comprising a rotor rotatably disposed within a stator to define a gap therebetween. A lubricant supply line extends from a high-pressure source to the lubricant-supported electric motor for supplying lubricant into the gap and for supporting the rotor within the stator. In a first embodiment, at least one powertrain component is configured to be in fluid communication with the lubricant supply line and in fluid parallel with the lubricant-supported electric motor for supplying lubricant to the at least one powertrain component. In an alternative embodiment, the at least one powertrain component is in fluid series with the lubricant-supported electric motor and is located downstream of the lubricant-supported electric motor for supplying lubricant from the lubricant-supported electric motor to the at least one powertrain component. In either embodiment, the lubricant-supported electric motor is incorporated into existing lubricant supply systems for electric or hybrid electric vehicles to reduce cost and complexity relative to existing designs of lubricant-supported electric motors, which require a dedicated lubricant supply for the lubricant-supported electric motor. Other advantages will be understood in light of the following more detailed description of the invention. Attached Figure Description

[0010] The accompanying drawings described in this application are for illustrative purposes only for selected embodiments and not all possible implementations, and are not intended to limit the scope of this disclosure.

[0011] Figure 1 This is a schematic diagram of a lubricant-supported electric motor according to one aspect of this disclosure;

[0012] Figure 2 This is a block diagram of a lubricant supply system for a lubricant-supported electric motor according to one aspect of this disclosure; and

[0013] Figure 3 This is a block diagram of an alternative arrangement of a lubricant supply system for a lubricant-supported electric motor according to another aspect of this disclosure. Detailed Implementation

[0014] Exemplary embodiments will now be described more fully. Specifically, several non-limiting embodiments of vehicle drivetrain components with wheel supports, which may or may not have end gear reduction units integrated with wheel-end motors, are provided so that this disclosure is thorough and will fully convey the true and contemplated scope to those skilled in the art. It will be apparent to those skilled in the art that not every specific detail needs to be adopted, exemplary embodiments may be implemented in many different forms, and therefore should not be construed as limiting the scope of this disclosure. In some exemplary embodiments, well-known processes, well-known device structures, and well-known technologies are not described in detail. It should also be understood that this disclosure may be used in conjunction with other types of vehicle components not fully described herein.

[0015] For electric or hybrid electric vehicles or other devices that can be configured with electric or hybrid electric powertrains (e.g., manufacturing equipment, construction machinery, programmable robots, power generation devices, etc.), the size and weight of the powertrain can be reduced by replacing the sliding or rolling element bearings on the traction motor rotor shaft and using lubricant to directly support the rotor on the stator. For example, Figure 1 A lubricant-supported electric motor 10 according to this disclosure is shown. For example... Figure 1 As best illustrated, the lubricated motor 10 includes a stator 12 and a rotor 14 movably disposed within the stator 12 to define a gap 16 between them. A lubricant 18 is disposed in the gap 16 to support the rotor 14 within the stator 12 and to provide continuous contact between these components. Thus, the lubricant 18 can act as a buffer (e.g., suspension) between the stator 12 and the rotor 14 to minimize or prevent contact between them. In other words, the lubricant 18 prevents direct contact between the stator 12 and the rotor 14 and provides an electrically lubricated motor 10 that is robust to shock and vibration loads. Alternatively, a substantially incompressible lubricant 18 may be used to minimize the gap between the stator 12 and the rotor 14.

[0016] like Figure 1As further shown, the stator 12 defines a channel 20 configured to be in fluid communication with the gap 16 for introducing lubricant 18. However, the channel 20 may be located on any other component of the lubricant-supported motor 10 without departing from the subject matter. According to one aspect, the lubricant 18 may be circulated or pumped through the channel 20 and into the gap 16 in various ways. For example, see reference... Figure 2-3 The lubricant supply system 30 may include a lubricant supply line 32 and a lubricant return line 36, wherein the lubricant supply line 32 supplies lubricant 18, for example, from a high-pressure source (e.g., a pump) 34, 34' to a lubricant-supported motor 10; the lubricant return line 36 captures lubricant 18 leaving the lubricant-supported motor 10 and returns lubricant 18 to a low-pressure source (e.g., a reservoir) 38. Thus, lubricant 18 can enter from the high-pressure source 34 via the lubricant supply line 32, through channel 20, through gap 16, and then via the lubricant return line 36 to the low-pressure source 38. This loop forms a flow path for lubricant 18 in the lubricant supply system 30. Figure 2 As shown, the pressure control device 35 can adjust the performance of the pump 34, as well as the output of the lubricant 18 from the pump 34 to the lubricant supply line 32 and to the motor 10 supporting the lubricant. Alternatively, as... Figure 3 As shown, pump 34 can be a variable flow pump 34', wherein pump pressure and flow rate are controlled by adjusting the pump motor speed or pump displacement. Furthermore, the rotation of rotor 14 relative to stator 12 can also function as a self-pumping mechanism to drive lubricant 18 through the fluid communication loop, through channel 20, and into gap 16.

[0017] like Figure 1 As further shown, rotor 14 is interconnected to drive assembly 22 for coupling the lubricated electric motor 10 to one of the vehicle's multiple wheels. For example, in one instance, drive assembly 22 may include a planetary gear system. Alternatively, drive assembly 22 may include one or more parallel shaft gears. Stator 12 and rotor 14 are configured to apply an electromagnetic force between them to convert electrical energy into mechanical energy, moving rotor 14 and ultimately driving the wheel coupled to the lubricated electric motor 10. Drive assembly 22 may provide one or more reduction ratios between the lubricated electric motor 10 and the wheel in response to the movement of rotor 14.

[0018] like Figure 2-3As shown, the lubricant 18 supplied to the lubricant-supported electric motor 10 utilizes the existing lubricant / cooling system of the powertrain of the electric or hybrid electric vehicle, i.e., the same lubricant / cooling supply line 32. By integrating the lubricant-supported electric motor 10 into the existing lubricant supply system 30 to draw lubricant from the existing lubricant supply line 32, the lubricant-supported electric motor 10 is advantageously implemented with reduced cost and complexity compared to prior art designs, since the electric or hybrid electric vehicle only requires one lubricant supply system 30. Therefore, according to the disclosure of this subject matter, other components of the electric or hybrid electric vehicle, such as, but not limited to, powertrain components (e.g., gearbox, power electronics, battery, gears, wheel bearings, etc.), can use the same lubricant / coolant supply line 32 as the lubricant-supported electric motor 10, thereby minimizing the cost of deploying the lubricant-supported electric motor 10 in the electric or hybrid electric vehicle. It should be understood that the lubricant can be used at least partially as both a coolant and a lubricant. Therefore, for the purposes of the remainder of the disclosure, it should be understood that the terms "lubricant" and "coolant" are used interchangeably herein.

[0019] like Figure 2 As best illustrated, at least one other powertrain component 42, 44, 46, 48 of an electric or hybrid electric vehicle is configured to be in fluid communication with the lubricant supply line 32 and connected in parallel with the lubricant-supported electric motor 10. At least one powertrain component 42, 44, 46, 48 may have different lubricant / coolant requirements than the lubricant-supported electric motor 10, and therefore must be controlled differently. Therefore, the motor control valve 50 is configured to be in fluid communication with the lubricant-supported electric motor 10, and component control valves 52, 54, 56, 58 are configured to be in fluid communication with each powertrain component 42, 44, 46, 48. For example, these supply control valves may be configured as variable orifice valves or duty cycle modulated on / off valves. The capillary tube 60 may also be configured to be in fluid communication between each control valve 50, 52, 54, 56, 58 and its corresponding component 10, 42, 44, 46, 48.

[0020] like Figure 2As further shown, controller 62 is configured to be electrically connected to motor control valve 50 and component control valves 52, 54, 56, 58, and is configured to individually control the flow of lubricant to connected components by adjusting control valves 50, 52, 54, 56, 58, according to the individual needs of the lubricant-supported motor 10 and at least one powertrain component 42, 44, 46, 48. Therefore, powertrain controller 62 maintains sufficient pump pressure and / or flow rate to efficiently and effectively supply all powertrain components from a common lubricant supply line 32 of lubricant supply system 30. As will be explained in more detail below, controller 62 may also be configured to be electrically connected to various sensors 63 in the powertrain system, including sensors configured to communicate with the lubricant-supported motor 10 and powertrain components 42, 44, 46, 48, for receiving information in real time based on the operating status of the powertrain components and adjusting control valves 50, 52, 54, 56, 58.

[0021] According to one aspect of this disclosure, at least one powertrain component 42, 44, 46, 48 may include a battery cooling device (e.g., a heat exchanger) 42, which is configured to be in fluid communication with a lubricant supply line 32 and connected in parallel with a lubricant-supported electric motor 10. A first component control valve 52 is configured to be in fluid communication between the lubricant supply line 32 and the battery cooling device 42, and a controller 62 is configured to independently operate the first component control valve 52 to direct lubricant / coolant 18 to the battery cooling device 42, thereby regulating (i.e., cooling) the temperature of one or more batteries. In one configuration, the controller 62 is also configured to be in electrical communication with a temperature sensor disposed on one or more batteries and is configured to use the temperature information to regulate the first component control valve 52.

[0022] According to one aspect of this disclosure, at least one powertrain component 42, 44, 46, 48 may further include a power electronic cooling device (e.g., a radiator) 44, which is configured to be in fluid communication with a lubricant supply line 32 and connected in parallel with a lubricant-supported electric motor 10. A second component control valve 54 is configured to be in fluid communication between the lubricant supply line 32 and the power electronic control device 44, and a controller 62 is configured to independently operate the second component control valve 54 to direct lubricant / coolant to the power electronic cooling device 44, thereby regulating the temperature (i.e., cooling) of the power electronic cooling device 44 and the connected power electronic device. In one configuration, the controller 62 is also configured to be in electrical communication with a temperature sensor disposed on the connected power electronic device and is configured to use the temperature information to regulate the second component control valve 54.

[0023] According to one aspect of this disclosure, at least one powertrain component 42, 44, 46, 48 may further include a gear and wheel bearing cooling device (e.g., a radiator) 46, which is configured to be in fluid communication with a lubricant supply line 32 and connected in parallel with a lubricant-supported electric motor 10. A third component control valve 56 is configured to be in fluid communication between the lubricant supply line 32 and the gear and wheel bearing cooling device 46, and a controller 62 is configured to independently operate the third component control valve 56 to direct lubricant / coolant to the gear and wheel bearing cooling device 46, thereby regulating the temperature (i.e., cooling) of the gear and wheel bearing cooling device 46 and the connected gears and bearings. In one configuration, the controller 62 is also configured to be in electrical communication with a temperature sensor disposed on the connected gears and bearings and is configured to use the temperature information to regulate the third component control valve 56.

[0024] According to one aspect of this disclosure, at least one powertrain component 42, 44, 46, 48 may include an electric motor stator cooling device (e.g., a radiator) 48, which is configured to be in fluid communication with a lubricant supply line 32 and connected in parallel with a lubricant-supported electric motor 10. A fourth component control valve 56 is configured to be in fluid communication between the lubricant supply line 32 and the electric motor stator cooling device 48, and a controller 62 is configured to independently operate the fourth component control valve 58 to direct lubricant / coolant to the electric motor stator cooling device 48, thereby regulating the temperature (i.e., cooling) of the electric motor stator cooling device 48 and the connected electric motor stator. In one configuration, the controller 62 is also configured to be in electrical communication with a temperature sensor disposed on the electric motor stator and is configured to use the temperature information to regulate the fourth component control valve 58.

[0025] Other components of the powertrain, such as vehicle climate control via heat exchangers, heat pumps, or radiators, may also be integrated into the lubricant supply system 30 without departing from the scope of this subject matter.

[0026] like Figure 2 As shown, the lubricant supply system 30 may include a common reservoir 38, located downstream of the lubricant-supported electric motor 10 and at least one power transmission component 42, 44, 46, 48. Therefore, after the controller 62 controls the electric motor control valve 50 and the component control valves 52, 54, 56, 58, the lubricant 18 passes through the respective components and reaches a common or shared lubricant return line 36, which returns the lubricant 18 to the common reservoir 38 for subsequent use by the pump 34.

[0027] Reference Figure 3In an alternative configuration of the lubricant supply system 30, at least one powertrain component 42, 44, 46, 48 of an electric or hybrid electric vehicle is configured to be in fluid communication with the lubricant supply line 32, but optionally connected in series with the lubricant-supported electric motor 10. In this configuration, the lubricant-supported electric motor 10 receives the flow of lubricant 18 directly from the pump 34', i.e., the lubricant supply line 32 first passes through the lubricant-supported electric motor 10 and then delivers the lubricant 18 to at least one powertrain component 42, 44, 46, 48. However, under certain operating conditions, the lubricant demand of at least one powertrain component 42, 44, 46, 48 is greater than the necessary lubricant flow through the lubricant-supported electric motor 10. Therefore, the lubricant supply system 30 includes a bypass valve 64 configured in a bypass loop parallel to the lubricant-supported electric motor 10. The controller 62 is also electrically connected to a bypass valve 64 and is configured to open the bypass valve 64 in response to determining that at least one powertrain component 42, 44, 46, 48 requires additional lubricant / coolant 18, allowing a larger flow of lubricant downstream of the lubricated motor 10. Additionally, if the demand of the lubricated motor 10 exceeds that of the downstream powertrain components 42, 44, 46, 48, the bypass valve 64 can refuse lubricant / coolant flow to the downstream components, which benefits the lubricated motor 10. Therefore, the bypass valve 64 allows the controller 62 to further control the pressure and flow rate of the lubricant 18 to meet the lubricant and cooling needs of at least one powertrain component 42, 44, 46, 48.

[0028] If at least one powertrain component 42, 44, 46, 48 includes multiple powertrain components, for example, Figure 3 As shown, each of the powertrain components 42, 44, 46, and 48 is configured to be connected in parallel to each other downstream of the lubricant-supported electric motor 10. The powertrain components 42, 44, 46, and 48 are then configured to be in fluid communication with a component return line 66, which returns the lubricant 18 to the reservoir 38 for subsequent use by the pump 34. Figure 2 The setup shown is similar, with each powertrain component 42, 44, 46, 48 having a corresponding component control valve 52, 54, 56, 58 for controlling the flow of lubricant 18 to the corresponding component.

[0029] like Figure 3As shown, the lubricant supply system 30 may further include a variable (i.e., adjustable) pressure regulator 68 connected to the lubricant supply line 32 and disposed between the pump 36 and the lubricant-supported motor 10. The variable pressure regulator 68 can regulate the pressure (and flow rate) of the lubricant / coolant 18 via the lubricant supply system 30. The controller 62 is also configured to be electrically connected to the variable pressure regulator 68 and is configured to adjust the variable pressure regulator 68 according to the needs of components fluidly connected within the lubricant supply system 30.

[0030] The lubricant supply system 30 may also include at least one pressure reducing valve 70', 70', configured along the lubricant supply line 32 or the lubricant return line 36 to release lubricant pressure and return lubricant to the reservoir 38. For example, as Figure 3 As shown, the lubricant supply system 30 may include a first pressure reducing valve 68' and a second pressure reducing valve 70', wherein the first pressure reducing valve 68' is disposed between the pump 34 and the variable pressure regulator 68 along the lubricant supply line 32, and the second pressure reducing valve 70' is disposed between at least one power transmission system component 42, 44, 46, 48 and the reservoir 38 along the lubricant return line 36.

[0031] In light of the foregoing disclosure, controller 62 addresses the efficiency, load capacity, and stiffness issues of the lubricant-supported electric motor 10 to provide better performance, smaller size, and lighter weight than sliding or rolling element bearing systems, while also controlling the flow of lubricant to other power transmission components to optimize their operation. According to one aspect of this disclosure, the lubricant-supported electric motor 10 can operate for extended periods in both hydrostatic and hydrodynamic modes. Additionally, and optionally, the lubricant-supported electric motor 10 can operate for very short periods in boundary lubrication mode. In at least all of these modes, optimal control of the lubricant supply is the goal of the lubricant supply system 30.

[0032] In hydrostatic mode (i.e., stopped and low-speed operation), lubricant / coolant 18 can be supplied by pump 34 to the hydrostatic recess region in the bearing of the lubricant-supported motor 10. Several different parameters are controlled to optimize bearing performance, including but not limited to:

[0033] 1) When stopped or running at low speed, the flow of lubricant to each bearing recess—for example, the flow of lubricant to each recess in the bearing can be through orifices (e.g., Figure 2 The capillary tube, proportional valve, or duty cycle modulation valve shown is limited to its maximum value. This restriction on the flow of lubricant achieves hydrostatic centering of the rotor 14 when there is an uneven gap 16 around the rotor / stator 12 / 14 interface of the lubricant-supported motor 10.

[0034] 2) During high-speed operation, the lubricant flow to each bearing recess is optimized to minimize pump operation. For example, when the hydrodynamic pressure is sufficient to support the bearing, the lubricant flow can be restricted to the hydrostatic bearing cross-section. This can be achieved by reducing the orifice size, reducing the capillary 60 size, reducing the pulse width modulation (PWM) valve duty cycle, or reducing the lubricant supply pressure.

[0035] 3) Lubricant supply pressure and flow – Maintain proper lubricant flow to the lubricant-supported motor 10. Since the lubricant supply system 30 is used by bearings or oil-cooling equipment in other power transmission systems, the lubricant supply pressure / flow is regulated to ensure sufficient lubricant supply to all connected receivers, components, and devices. Furthermore, the power requirements of the pump 34 are minimized by always providing the lowest acceptable pressure.

[0036] 4) Lubricant viscosity – Lubricant viscosity can be controlled by adjusting the lubricant temperature, mixing colder or hotter lubricants, and / or changing the lubricant grade. The lubricant supply system 30 can generate diagnostic codes to indicate inappropriate lubricant viscosity for a given operation.

[0037] 5) Battery charge level - Precharge the reservoir 38 to high voltage when the motor is off to pre-adjust the reservoir 38 for the next start of the lubricant-supported motor 10.

[0038] 6) Hydrostatic Model Diagnostics - Use at least the following parameters to observe the correct operation of the lubricant supply: lubricant supply pressure, lubricant supply temperature, lubricant supply flow, rotor centering, or rotor radial vibration. One or more of these parameters can be used to generate diagnostic indicators.

[0039] 7) Lubricant supply during motor startup - During the startup of a lubricated motor, lubricant can be used to pressurize the hydrostatic chamber, and rotor centering can be observed. When these and other motor startup conditions are met, controller 62 allows the motor to start. For example, during startup, lubricant can be supplied by pump 34 or reservoir 38.

[0040] 8) For emergency or abnormal start-up operations - controller 62 ensures that sufficient lubricant remains on the bearing surfaces to provide boundary lubrication. Alternatively, a lubricant pump (not shown) for auxiliary wheel operation can be used to supply lubricant, for example, during vehicle traction operations or in other situations where normal lubricant supply is not available.

[0041] According to one aspect of this disclosure, in a low-speed hydrostatic mode, the electric motor may require the highest level of lubricant flow to support (i.e., suspend) the rotor 14 in the stator 12. As per [other details] Figure 2 and Figure 3 The other powertrain components discussed are using the same lubricant supply system 30 and may have low lubricant flow requirements for lubrication and cooling purposes. Therefore, the controller 62 is configured to direct lubricant flow to each component of the powertrain according to the specific lubrication and cooling requirements of the powertrain.

[0042] According to one aspect of this disclosure, in medium- and high-speed hydrodynamic modes, it may be necessary to continuously supply a lower level of lubricant to the lubricated motor 10. Similar to the hydrostatic mode, several parameters are controlled to ensure proper operation of the motor and associated power transmission system:

[0043] 1) Supplying lubricant to the hydrodynamic bearing of the electric motor - The controller controls the flow of lubricant to the lubricant-supported electric motor 10 to ensure proper bearing operation. The lubricant flow rate can be controlled via a variable orifice, a duty cycle modulation valve, and / or by changing the pressure of pump 34.

[0044] 2) Supplying lubricant to relevant systems - Controller 62 ensures that appropriate lubricant is supplied to other components of the power transmission system with pump pressure control and variable valves.

[0045] 3) Lubricant viscosity - The viscosity of lubricant / coolant can be controlled by adjusting the lubricant temperature, mixing lubricants at different temperatures, and changing the lubricant grade (i.e., viscosity).

[0046] 4) Fluid Dynamics Mode Diagnostics - The controller observes the proper operation of the lubricant supply through at least the following parameters: lubricant supply pressure, lubricant supply temperature, lubricant supply flow, motor rotor centering, or rotor radial vibration. One or more of these parameters can be used to generate diagnostic indicators.

[0047] 5) Lubricant supply during the switch from hydrostatic to hydrodynamic mode - During the switch from hydrostatic motor bearing operation to hydrodynamic motor bearing operation, the controller 62 ensures proper operation of the electric motor bearing and minimizes the operation of the lubricant pump by controlling the lubricant pressure and the flow of lubricant to the lubricated motor.

[0048] 6) Lubricant Supply During Emergency or Abnormal Lubrication System Operation – The controller ensures adequate lubricant supply during hydrodynamic operation by including a wheel-driven lubricant pump (not shown) or by a self-pumping function including the surface of the motor bearings. For example, the rotor 14 of the lubricant-supported motor 10 may have small helical grooves on its raceway to draw in lubricant for hydrodynamic operation when the normal lubricant supply system 30 may not be operational. This configuration, along with lubricant “immersion” in the motor housing, ensures adequate lubricant supply.

[0049] According to one aspect of this disclosure, when the lubricant-supported motor 10 can be stopped and lubricant / cooling is not required, the flow of lubricant to the lubricant-supported motor 10 can be temporarily stopped. Additionally and optionally, other downstream power transmission components 42, 44, 46, 48 of the lubricant-supported motor 10 may also encounter operating conditions where the lubricant / coolant flow may not be required for lubrication and / or cooling. In these cases, the lubricant / coolant flow can be stopped to save energy for the pump 34.

[0050] Obviously, many modifications and variations of this disclosure are possible based on the foregoing teachings, and may be implemented in ways different from those specifically described within the scope of the appended claims. Individual elements or features of a particular embodiment are generally not limited to that particular embodiment, but are interchangeable where applicable, and may be used in selected embodiments even if not specifically shown or described.

Claims

1. A lubricant supply system for an electric or hybrid electric vehicle, characterized in that, The lubricant supply system includes: a lubricant supported electric motor including a rotor rotatably disposed within a stator to define a gap therebetween; a lubricant supply line extending from a high pressure source to the lubricant supported electric motor for supplying lubricant to the gap and for supporting the rotor within the stator; at least one powertrain component disposed in fluid communication with the lubricant supply line and in fluid parallel connection with the lubricant supported electric motor for supplying lubricant to the at least one powertrain component; and the lubricant supported electric motor and the at least one powertrain component are disposed in fluid communication with a lubricant return line for receiving lubricant exiting the lubricant supported electric motor and the at least one powertrain component and returning the received lubricant to a low pressure source.

2. The lubricant supply system according to claim 1, characterized by The lubricant supply system further includes: an electric motor control valve disposed in fluid communication with the lubricant supported electric motor; and a component control valve disposed in fluid communication with the at least one powertrain component, and a controller disposed in electrical communication with the electric motor and the component control valve and structured to regulate the electric motor and the component control valve for individually controlling flow of lubricant to the lubricant supported electric motor and the at least one powertrain component.

3. The lubricant supply system according to claim 2, characterized by The controller is disposed in electrical communication with a sensor disposed in communication with each of the lubricant supported electric motor and the at least one powertrain component and the controller is further structured to regulate the electric motor and control valve in response to operational information received from the sensor.

4. The lubricant supply system of claim 1, wherein The rotor of the lubricant supported electric motor is operably connected to a final drive interconnected to a wheel of the electric or hybrid electric vehicle.

5. The lubricant supply system of claim 1, wherein The at least one powertrain component includes at least one of a battery cooling device, a power electronics cooling device, a gear and wheel bearing cooling device or a motor stator cooling device.

6. The lubricant supply system of claim 1, wherein The low pressure source is a common sump disposed downstream of the lubricant supported electric motor and the at least one powertrain component.

7. The lubricant supply system of claim 2, wherein The lubricant supply system includes a plurality of powertrain components each disposed in fluid communication with the lubricant supply line and in fluid parallel connection with the lubricant supported electric motor for supplying lubricant to each of the plurality of powertrain components and the component control valve includes a plurality of component control valves each disposed in fluid communication with a respective one of the powertrain components.

8. A lubricant supply system for an electric or hybrid electric vehicle, characterized by The lubricant supply system includes: a lubricant supported electric motor including a rotor rotatably disposed within a stator to define a gap therebetween; a lubricant supply line extending from a high pressure source to the lubricant supported electric motor for supplying lubricant to the gap and supporting the rotor within the stator; and at least one powertrain component fluidly connected in series with the lubricant supported electric motor and downstream of the lubricant supported electric motor for supplying lubricant from the lubricant supported electric motor to the at least one powertrain component.

9. The lubricant supply system according to claim 8, characterized in that, The lubricant supply system further comprises: an electric motor control valve disposed in fluid communication with the lubricant supported electric motor; and a component control valve disposed in fluid communication with the at least one powertrain component, and a controller disposed in electrical communication with the electric motor and the component control valve and configured to regulate the electric motor and the component control valve for individually controlling the flow of lubricant to the lubricant supported electric motor and the at least one powertrain component.

10. The lubricant supply system of claim 9, wherein The controller is disposed in electrical communication with sensors disposed in communication with each of the lubricant supported electric motor and the at least one powertrain component and the controller is further configured to regulate the electric motor and control valves in response to operational information received from the sensors.

11. The lubricant supply system of claim 9, wherein The lubricant supply system further comprises a bypass valve disposed in fluid communication with the lubricant supply line and disposed in a bypass circuit in parallel with the lubricant supported electric motor and the controller is disposed in electrical communication with the bypass valve for bypassing the flow of lubricant through the lubricant supported electric motor and increasing the flow of lubricant to the at least one powertrain component.

12. The lubricant supply system of claim 11, wherein, The lubricant supply system comprises a plurality of powertrain components each disposed in parallel with each other downstream of the lubricant supported electric motor.

13. The lubricant supply system of claim 9, wherein The lubricant supply system further comprises a variable pressure regulator connected to the lubricant supply line and disposed between the high pressure source and the lubricant supported electric motor and the controller is disposed in electrical communication with the variable pressure regulator.

14. The lubricant supply system of claim 13, wherein, The lubricant supply system further comprises a pressure reducing valve disposed along the lubricant supply system between the high pressure source and the variable pressure regulator.

15. The lubricant supply system of claim 8, wherein, The rotor of the lubricant supported electric motor is operably connected to a final drive interconnected to wheels of the electric or hybrid electric vehicle.

16. The lubricant supply system of claim 8, wherein The at least one powertrain component comprises at least one of a battery cooling device, a power electronics cooling device, a gear and wheel bearing cooling device or a motor stator cooling device.

17. The lubricant supply system of claim 8, wherein, Each of the lubricant supported electric motor and the at least one powertrain component is disposed in fluid communication with a common low pressure source for returning lubricant exiting the lubricant supported electric motor and the at least one powertrain component to the low pressure source.

18. The lubricant supply system of claim 17, wherein, The low pressure source is a common sump disposed downstream of the motor and the at least one power transmission component supported by the lubricant. The low pressure source is a common sump disposed downstream of the motor and the at least one power transmission component supported by the lubricant.

Images