Patent Description:
An axle assembly having an electric motor according to the preamble of claims <NUM> and <NUM> is disclosed in <CIT>. <CIT> discloses a hybrid drivetrain that has an internal combustion engine that is connected to an electrical machine with a torsion damper. A countershaft transmission is connected to the torsion damper with a transmission input shaft and is connected to a differential via a transmission output shaft and a spur gear arrangement. <CIT> discloses a hybrid transmission coupling bridge structure that includes first and second motors and first and second gearboxes. <CIT> discloses a hybrid drive system for a motor vehicle having first and second transmission input shafts that may be coupled to or decoupled from first and second gear stages. <CIT> discloses A drivetrain system with a rotor and a differential mechanism that are rotatable about one axis while a layshaft (auxiliary shaft) is rotatable about a different axis. The document shows a shift collar that is rotatable about the first axis with the auxiliary shaft and selectively couples the auxiliary shaft to the drive pinion, the gear reduction module, or the drive pinion (<NUM>) and the gear reduction module and further discloses that the shift collar is configured to selectively couple the gear reduction module to the auxiliary shaft or the drive pinion.

According to the invention, a drivetrain system is provided as set out in claim <NUM>.

Referring to <FIG>, an example of a drivetrain system <NUM> is shown. The drivetrain system <NUM> includes an axle assembly <NUM>. The axle assembly <NUM> may provide torque to one or more traction wheel assemblies that may include a tire mounted on a wheel. The wheel may be mounted to a wheel hub that may be rotatable about an axis.

One or more axle assemblies may be provided with the vehicle. As is best shown with reference to <FIG> and <FIG>, the axle assembly <NUM> may include a housing assembly <NUM>, includes a drive pinion <NUM>, an electric motor module <NUM>, a gear reduction module <NUM>, an auxiliary shaft <NUM>, a shift mechanism <NUM>, a differential assembly <NUM>, and may include at least one axle shaft <NUM>.

In addition, the housing assembly <NUM> may include portions that may receive and/or facilitate mounting of the electric motor module <NUM>, the shift mechanism <NUM>, or both.

The axle housing <NUM> may receive and may support the axle shafts <NUM>. In at least one embodiment, the axle housing <NUM> may include a center portion <NUM> and at least one arm portion <NUM>.

The center portion <NUM> may be disposed proximate the center of the axle housing <NUM>. The center portion <NUM> may define a cavity that may receive the differential assembly <NUM>. A lower region of the center portion <NUM> may at least partially define a sump portion that may contain a first lubricant. Splashed lubricant may flow down the sides of the center portion <NUM> and may flow over various internal components of the axle assembly <NUM> and gather in the sump portion.

One or more arm portions <NUM> may extend from the center portion <NUM>. For example, two arm portions <NUM> may extend in opposite directions from the center portion <NUM> and away from the differential assembly <NUM>. The arm portions <NUM> may have substantially similar configurations. For example, the arm portions <NUM> may each have a hollow configuration or tubular configuration that may extend around and may receive a corresponding axle shaft <NUM> and may help separate or isolate the axle shaft <NUM> or a portion thereof from the surrounding environment. An arm portion <NUM> or a portion thereof may be integrally formed with the center portion <NUM>. Alternatively, an arm portion <NUM> may be separate from the center portion <NUM>. In such a configuration, each arm portion <NUM> may be attached to the center portion <NUM> in any suitable manner, such as by welding or with one or more fasteners. An arm portion may rotatably support an associated wheel hub. It is also contemplated that the arm portions <NUM> may be omitted.

Referring to <FIG> and <FIG>, the differential carrier <NUM>, which may also be called a carrier housing, may be mounted to the center portion <NUM> of the axle housing <NUM>. The differential carrier <NUM> may support the differential assembly <NUM>. In at least one configuration, the differential carrier <NUM> may facilitate mounting of the electric motor module <NUM>.

Referring to <FIG>, the drive pinion <NUM> may provide torque to a ring gear that may be provided with the differential assembly <NUM>. Moreover, the drive pinion <NUM> may help operatively connect the gear reduction module <NUM> to the differential assembly <NUM>. The drive pinion <NUM> may extend along and is rotatable about a first axis <NUM>. In addition, the drive pinion <NUM> may extend through a hole in the differential carrier <NUM>. In at least one configuration, the drive pinion <NUM> may include a gear portion <NUM> and a shaft portion <NUM>.

The gear portion <NUM> may be disposed at or near an end of the shaft portion <NUM>. The gear portion <NUM> may have a plurality of teeth that may mate or mesh with corresponding teeth on the ring gear. The gear portion <NUM> may be integrally formed with the shaft portion <NUM> or may be provided as a separate component that may be fixedly disposed on the shaft portion <NUM>.

The shaft portion <NUM> may extend from the gear portion <NUM> in a direction that extends away from the axle housing <NUM>. The shaft portion <NUM> may be rotatably supported by one or more drive pinion bearings and may include a drive pinion spline <NUM>, which is best shown in <FIG>.

Referring to <FIG>, the drive pinion spline <NUM> may be disposed near an end of the shaft portion <NUM> that may be disposed opposite the gear portion <NUM>. The drive pinion spline <NUM> may include a plurality of teeth. The teeth may be disposed substantially parallel to the first axis <NUM> and may mate with a corresponding spline on a shift collar of the shift mechanism <NUM> as will be discussed in more detail below.

Referring to <FIG>, the electric motor module <NUM> may provide torque to the differential assembly <NUM> via the drive pinion <NUM>, the gear reduction module <NUM>, and the shift mechanism <NUM>. In at least one configuration, the electric motor module <NUM> may be mounted to the differential carrier <NUM> and may be axially positioned between the axle housing <NUM> and the gear reduction module <NUM>. In at least one configuration, the electric motor module <NUM> includes a stator <NUM>, a rotor <NUM>, and may include at least one rotor bearing assembly <NUM>.

The stator <NUM> may be fixedly positioned with respect to the housing assembly <NUM>. For example, the stator <NUM> may extend around the first axis <NUM> and may not rotate about the first axis <NUM>. The stator <NUM> may include windings that may be electrically connected to an electrical power source, such as a battery, capacitor, or the like. An inverter may electrically connect the electric motor module <NUM> and the electrical power source.

The rotor <NUM> may be rotatable about the first axis <NUM> with respect to the differential carrier <NUM> and the stator <NUM>. For example, the rotor <NUM> may be spaced apart from the stator <NUM> but may be disposed close to the stator <NUM>. The rotor <NUM> may include magnets or ferromagnetic material that may facilitate the generation of electrical current.

One or more rotor bearing assemblies <NUM> may rotatably support the rotor <NUM>. In at least one configuration, a rotor bearing assembly <NUM> may receive a bearing support wall of the differential carrier <NUM> and may be received inside of the rotor <NUM>.

A rotor shaft <NUM> or rotor coupling operatively connects the rotor <NUM> to the gear reduction module <NUM>. For example, the rotor shaft <NUM> may extend from the rotor <NUM> or may be operatively connected to the rotor <NUM> such that the rotor <NUM> and the rotor shaft <NUM> may be rotatable together about the first axis <NUM>. The rotor shaft <NUM> may be fixedly coupled to the rotor <NUM> at or proximate a first end of the rotor shaft <NUM> and may be coupled to the gear reduction module <NUM> proximate a second end.

Referring to <FIG>, the gear reduction module <NUM> may transmit torque between the electric motor module <NUM> and the drive pinion <NUM>.

The gear reduction module <NUM> may be provided in various configurations, such as planetary gear set configurations and non-planetary gear set configurations. In <FIG>, the gear reduction module <NUM> has a planetary gear set <NUM>. In such a configuration, the gear reduction module <NUM> may include a sun gear <NUM>, planet gears <NUM>, a planetary ring gear <NUM>, and a planet gear carrier <NUM>.

Referring primarily to <FIG>, the sun gear <NUM> may be disposed proximate the center of the planetary gear set <NUM> and may be rotatable about the first axis <NUM>. In at least one configuration, the sun gear <NUM> may be configured as a hollow tubular body that may include a sun gear hole <NUM>, a sun gear spline <NUM>, a first gear portion <NUM>, and a second gear portion <NUM>.

The sun gear hole <NUM> may be a through hole that may extend through the sun gear <NUM>. The sun gear hole <NUM> may extend along and may be centered about the first axis <NUM>. The drive pinion <NUM> may extend through the sun gear hole <NUM> and may be spaced apart from the sun gear <NUM>.

The sun gear spline <NUM> may facilitate coupling of the sun gear <NUM> to a rotor shaft <NUM>. In at least one configuration, the sun gear spline <NUM> may be disposed opposite the sun gear hole <NUM> and may have teeth that may extend away from the sun gear hole <NUM>. As such, the sun gear spline <NUM> may be received inside the rotor shaft <NUM> and may mesh or mate with corresponding teeth on the rotor shaft <NUM>. It is also contemplated that the sun gear spline <NUM> may be disposed in the sun gear hole <NUM> and the rotor shaft <NUM> may be received inside the sun gear <NUM>.

The first gear portion <NUM> may be disposed in the sun gear hole <NUM>. Teeth of the first gear portion <NUM> may be arranged around the first axis <NUM>, may extend toward the first axis <NUM>, and may be configured to mesh with teeth of a shift collar <NUM> as will be discussed in more detail below.

The second gear portion <NUM> may be disposed opposite the sun gear hole <NUM> and may have teeth that may extend away from the sun gear hole <NUM>. The teeth of the second gear portion <NUM> may mate or mesh with teeth of the planet gears <NUM>.

Referring to <FIG> and <FIG>, the planet gears <NUM> may be rotatably disposed between the sun gear <NUM> and the planetary ring gear <NUM>. Each planet gear <NUM> may have a hole and a set of teeth. The hole may be a through hole that may extend through the planet gear <NUM>. The set of teeth may be disposed opposite the hole. The set of teeth may mesh with teeth of the second gear portion <NUM> of the sun gear <NUM> and teeth on the planetary ring gear <NUM>. The teeth may have any suitable configuration. In the configuration shown, the teeth are provided with a helical configuration however, other tooth configurations may be provided. Each planet gear <NUM> may be configured to rotate about a different planet gear axis of rotation. The planet gear axes of rotation may extend substantially parallel to the first axis <NUM>.

Referring to <FIG>, the planetary ring gear <NUM> may extend around the first axis <NUM> and may receive the planet gears <NUM>. The planetary ring gear <NUM> may include a set of planetary ring gear teeth that may extend toward the first axis <NUM> and may mesh with teeth on the planet gears <NUM>. The planetary ring gear <NUM> may be stationary with respect to the first axis <NUM>. For example, the planetary ring gear <NUM> may be received in and may be fixedly disposed on the housing assembly <NUM>.

Referring to <FIG> and <FIG>, the planet gear carrier <NUM> may be rotatable about the first axis <NUM> and may rotatably support the planet gears <NUM>. For instance, each planet gear <NUM> may be rotatably disposed on a corresponding pin that may extend from the planet gear carrier <NUM>. In at least one configuration, the planet gear carrier <NUM> may include a planet gear carrier hole <NUM>, a planet gear carrier ring <NUM>, and a planet gear carrier gear portion <NUM>.

Referring to <FIG>, the planet gear carrier hole <NUM> may be a through hole that may extend through planet gear carrier <NUM>. The planet gear carrier hole <NUM> may extend along and may be centered about the first axis <NUM>.

The planet gear carrier ring <NUM> may extend around the first axis <NUM> and may at least partially define the planet gear carrier hole <NUM>. The planet gear carrier ring <NUM> may be received in and may be rotatably supported by a support bearing <NUM>.

The planet gear carrier gear portion <NUM> may be disposed in the planet gear carrier ring <NUM> and may extend into the planet gear carrier hole <NUM>. Teeth of the planet gear carrier gear portion <NUM> may be arranged around the first axis <NUM> and may extend toward the first axis <NUM>.

Referring to <FIG>, the auxiliary shaft <NUM> may protrude from the housing assembly <NUM>. For example, the auxiliary shaft <NUM> may protrude from the housing assembly <NUM> and may extend away from the electric motor module <NUM> and the axle housing <NUM>. According to the invention, the auxiliary shaft <NUM> is rotatable about the first axis <NUM>. The auxiliary shaft <NUM> may function as an output from the axle assembly <NUM>, an input to the axle assembly <NUM>, or combinations thereof. For example, the auxiliary shaft <NUM> may function as an output or a power take-off (PTO) that may transfer power or torque from the axle assembly <NUM> to an auxiliary device <NUM> that may be operatively connected to the auxiliary shaft <NUM>. Examples of an auxiliary device <NUM> include but are not limited to a pump, ladder, vacuum, blower, compressor, winch, mechanical arm, compactor, boom, grapple, tree spade, dump truck bed lift, or the like. The auxiliary shaft <NUM> may also function as an input that may receive power or torque from an auxiliary device <NUM>, such as engine like an internal combustion engine. As is best shown in <FIG>, the auxiliary shaft <NUM> is spaced apart from the drive pinion <NUM>. In at least one configuration, the auxiliary shaft <NUM> may include an auxiliary shaft spline <NUM>.

The auxiliary shaft spline <NUM> may mate or selectively mate with a corresponding spline on a shift collar of the shift mechanism <NUM> as will be discussed in more detail below. For example, the auxiliary shaft spline <NUM> may include a plurality of teeth that may be disposed substantially parallel to the first axis <NUM> and that may permit axial movement of the shift collar along the first axis <NUM>.

Referring to <FIG>, the shift mechanism <NUM> may help control the transmission of torque through the axle assembly <NUM>. According to the invention, the shift mechanism <NUM> includes a shift collar <NUM>, and may include an actuator <NUM>, and a linkage <NUM>.

Referring to <FIG>, the shift collar <NUM> selectively couples and decouples components of the axle assembly <NUM> such as the drive pinion <NUM>, the gear reduction module <NUM>, the auxiliary shaft <NUM>, or combinations thereof. In at least one configuration, the shift collar <NUM> may receive the drive pinion <NUM>. The auxiliary shaft <NUM> may be partially received in the planet gear carrier <NUM>. In the configuration shown in <FIG>, the shift collar <NUM> may include a shift collar hole <NUM>, a first shift collar spline <NUM>, a second shift collar spline <NUM>, a shift collar groove <NUM>, and a shift collar gear <NUM>.

The shift collar hole <NUM> may extend through the shift collar <NUM> and may extend around the first axis <NUM>. The shift collar hole <NUM> may receive the shaft portion <NUM> of the drive pinion <NUM> and the auxiliary shaft <NUM>.

The first shift collar spline <NUM> may be disposed in the shift collar hole <NUM> and may be axially positioned near a first end of the shift collar <NUM>. The first shift collar spline <NUM> may extend toward the first axis <NUM> and may mate or mesh with the drive pinion spline <NUM> of the drive pinion <NUM>. The mating splines may allow the shift collar <NUM> to move in an axial direction along the first axis <NUM> while inhibiting rotation of the shift collar <NUM> about the first axis <NUM> with respect to the drive pinion <NUM>. Thus, the shift collar <NUM> may be rotatable about the first axis <NUM> with the drive pinion <NUM> when the shift collar <NUM> is coupled to the drive pinion <NUM> such that the first shift collar spline <NUM> mates or meshes with the drive pinion spline <NUM> of the drive pinion <NUM>.

The second shift collar spline <NUM> may be disposed in the shift collar hole <NUM> and may be axially positioned near a second end of the shift collar <NUM>. The second shift collar spline <NUM> may extend toward the first axis <NUM> and may mate or mesh with a spline of the auxiliary shaft <NUM>. The mating splines may allow the shift collar <NUM> to move in an axial direction along the first axis <NUM> while inhibiting rotation of the shift collar <NUM> about the first axis <NUM> with respect to the auxiliary shaft <NUM>. Thus, the shift collar <NUM> may be rotatable about the first axis <NUM> with the auxiliary shaft <NUM> when the shift collar <NUM> is coupled to the auxiliary shaft <NUM> such that the second shift collar spline <NUM> mates or meshes with the auxiliary shaft spline <NUM> of the auxiliary shaft <NUM>.

The shift collar groove <NUM> may face away from the first axis <NUM> and may extend around the first axis <NUM>. The shift collar groove <NUM> may receive the linkage <NUM>.

The shift collar gear <NUM> may be disposed between the first end and the second end of the shift collar <NUM>. The shift collar gear <NUM> may have at least one set of teeth that may be arranged around the first axis <NUM> and that may extend away from the first axis <NUM>. In the configuration shown in <FIG>, the shift collar gear <NUM> includes a first set of teeth <NUM> and a second set of teeth <NUM>. An annular groove <NUM> may be provided between the first set of teeth <NUM> and the second set of teeth <NUM>. The annular groove <NUM> may extend around the first axis <NUM> and may separate the first set of teeth <NUM> and the second set of teeth <NUM>.

Referring to <FIG>, the actuator <NUM> may be configured to move the shift collar <NUM> along the first axis <NUM>. The actuator <NUM> may be of any suitable type. For example, the actuator <NUM> may be an electrical, electromechanical, pneumatic or hydraulic actuator.

Referring to <FIG>, the linkage <NUM> may operatively connect the actuator <NUM> to the shift collar <NUM>. For example, the linkage <NUM> may be configured as a shift fork that may extend from the shift collar <NUM> to the actuator <NUM>. In at least one configuration, the linkage <NUM> may be received in the shift collar groove <NUM>.

A control system may be provided with the drivetrain system <NUM>. The control system may include one or more electronic controllers, such as a microprocessor-based controller. The control system may control operation of the axle assembly <NUM>. For example, the controller may receive signals from various sensors, such as rotational speed sensors that may provide signals indicative of the rotational speed of a wheel, the axle shaft <NUM>, the drive pinion <NUM>, the sun gear <NUM>, the rotor <NUM>, or combinations thereof. In addition, the control system may control the actuator <NUM> and thereby control movement of the shift collar <NUM>.

Referring to <FIG>, the differential assembly <NUM> may be at least partially received in the center portion <NUM> of the housing assembly <NUM>. The differential assembly <NUM> may transmit torque to the wheels and permit the wheels to rotate at different velocities. The differential assembly <NUM> may be operatively connected to the axle shafts <NUM> and may permit the axle shafts <NUM> to rotate at different rotational speeds in a manner known by those skilled in the art. The differential assembly <NUM> may have a ring gear <NUM> that may have teeth the mate or mesh with the teeth of the gear portion <NUM> of the drive pinion <NUM>. Accordingly, the differential assembly <NUM> may receive torque from the drive pinion <NUM> via the ring gear <NUM> and transmit torque to the axle shafts <NUM>.

Referring to <FIG> and <FIG>, the axle shafts <NUM> may transmit torque from the differential assembly <NUM> to corresponding wheel hubs and wheels. Two axle shafts <NUM> may be provided such that each axle shaft <NUM> extends through a different arm portion <NUM> of axle housing <NUM>. The axle shafts <NUM> may extend along and may be rotatable about the second axis <NUM>. Each axle shaft <NUM> may have a first end and a second end. The first end may be operatively connected to the differential assembly <NUM>. The second end may be disposed opposite the first end and may be operatively connected to a wheel. Optionally, gear reduction may be provided between an axle shaft <NUM> and a wheel.

Referring to <FIG>, operation of the drivetrain system <NUM> will now be discussed in more detail. In these figures, the straight arrowed lines represent the transmission of torque. In <FIG>, the shift collar <NUM> may be rotatable about the first axis <NUM> with the auxiliary shaft <NUM> and may selectively couple the auxiliary shaft <NUM> to the drive pinion <NUM>, the gear reduction module <NUM>, or the drive pinion <NUM> and the gear reduction module <NUM>. In <FIG>, the shift collar may selectively couple the gear reduction module <NUM> to the auxiliary shaft <NUM> or the drive pinion <NUM>.

Referring to <FIG>, the auxiliary shaft <NUM> is configured to function as an output or power take-off and is operatively connected to at least one auxiliary device <NUM>.

In <FIG>, the shift collar <NUM> is shown in a first position. In the first position, the shift collar <NUM> may couple the drive pinion <NUM> and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM> and the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>. The shift collar <NUM> may be decoupled from the gear reduction module <NUM> when the shift collar <NUM> is in the first position. For instance, the shift collar gear <NUM> may be spaced apart from and may not mate or mesh with the second gear portion <NUM> of the sun gear <NUM> or the planet gear carrier gear portion <NUM> of the planet gear carrier <NUM>. Accordingly, the electric motor module <NUM> may not provide torque to the drive pinion <NUM> or the auxiliary shaft <NUM> or receive torque from the drive pinion <NUM> or the auxiliary shaft <NUM>. The drive pinion <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be coupled but may not rotate about the first axis <NUM> when the vehicle is stationary. The drive pinion <NUM>, shift collar <NUM>, and the auxiliary shaft <NUM> may be coupled and may rotate about the first axis <NUM> when the vehicle is coasting and torque is provided from the rotating vehicle wheels to the drive pinion <NUM> via the axle shafts <NUM> and the differential assembly <NUM>.

In <FIG>, the shift collar <NUM> is shown in a second position. In the second position, the shift collar <NUM> may couple the drive pinion <NUM>, the planet gear carrier <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the planet gear carrier <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the second set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the planet gear carrier gear portion <NUM>. The second position may also be referred to as a low range position in which the gear reduction module <NUM> may provide a low range gear ratio.

The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM>, the sun gear <NUM> may provide torque to the planet gear carrier <NUM> via the planet gears <NUM>, and the planet gear carrier <NUM> may provide torque to the drive pinion <NUM> and the auxiliary shaft <NUM> via the shift collar <NUM> when the shift collar is in the second position and the electrical power source provides electrical power to the electric motor module <NUM>. In addition, it is contemplated that the electric motor module <NUM> may receive torque or may act as a generator that may charge the electrical power source when the vehicle is coasting, in which case torque may be provided from the rotating vehicle wheels to the drive pinion <NUM> via the axle shafts <NUM> and the differential assembly <NUM>, and thus the drive pinion <NUM> may provide torque to the auxiliary shaft <NUM> and to the electric motor module <NUM> via the planet gear carrier <NUM> of the gear reduction module <NUM> when the shift collar <NUM> is in the second position. The shift collar <NUM> may be decoupled from the sun gear <NUM> when the shift collar <NUM> is in the second position.

In <FIG>, the shift collar <NUM> is shown in a third position. In the third position, the shift collar <NUM> may couple the drive pinion <NUM>, the sun gear <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the sun gear <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the first set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The third position may also be referred to as a high range position in which the gear reduction module <NUM> may provide a high range gear ratio. The high range gear ratio may provide a different gear reduction ratio or lesser gear reduction ratio than the low range gear ratio. As a nonlimiting example, the high range gear ratio may provide a <NUM>:<NUM> gear ratio. The second drive gear ratio may facilitate faster vehicle cruising or a cruising gear ratio that may help improve fuel economy.

The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM> and the sun gear <NUM> may provide torque to the drive pinion <NUM> and the auxiliary shaft <NUM> via the shift collar <NUM> when the shift collar is in the third position and the electrical power source provides electrical power to the electric motor module <NUM>. In addition, it is contemplated that the electric motor module <NUM> may receive torque or may act as a generator that may charge the electrical power source when the vehicle is coasting, in which case torque may be provided from the rotating vehicle wheels to the drive pinion <NUM> via the axle shafts <NUM> and the differential assembly <NUM> and thus the drive pinion <NUM> may provide torque to the auxiliary shaft <NUM> and to the electric motor module <NUM> via the sun gear <NUM> of the gear reduction module <NUM> when the shift collar <NUM> is in the third position. The shift collar <NUM> may be decoupled from the planet gear carrier <NUM> when the shift collar <NUM> is in the third position.

In <FIG>, the shift collar <NUM> is shown in a fourth position. In the fourth position, the shift collar <NUM> may couple the sun gear <NUM> of the gear reduction module <NUM> to the auxiliary shaft <NUM> such that the sun gear <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM> and the second set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The fourth position may also be a high range position in which the gear reduction module <NUM> may provide a high range gear ratio or the same gear ratio as the third position. The drive pinion <NUM> may be decoupled from the shift collar <NUM> when the shift collar <NUM> is in the fourth position. For example, the first shift collar spline <NUM> may be decoupled from and may not mate or mesh with the drive pinion spline <NUM>.

The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM> and the sun gear <NUM> may provide torque to the auxiliary shaft <NUM> via the shift collar <NUM> when the shift collar is in the fourth position and the electrical power source provides electrical power to the electric motor module <NUM>. Accordingly, the fourth position may be employed when the vehicle is stationary and it is desired to provide power to the auxiliary shaft <NUM>. In addition, it is contemplated that shift collar <NUM> may be configured to provide torque to the auxiliary shaft <NUM> via the planet gear carrier <NUM> rather than the sun gear <NUM> when the shift collar <NUM> is decoupled from the drive pinion <NUM>.

Referring to <FIG>, the auxiliary shaft <NUM> may be configured to function as an input and may receive torque from an auxiliary device <NUM>, such as an internal combustion engine. For instance, the auxiliary device <NUM> may be a torque source that is connected in a series hybrid configuration. The shift collar positions in <FIG> match those shown in <FIG>, but the torque transmission paths are different since the auxiliary shaft <NUM> may function as an input rather than an output.

In <FIG>, the shift collar <NUM> is shown in a first position. In the first position, the shift collar <NUM> may couple the drive pinion <NUM> and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM> and the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>. The shift collar <NUM> may be decoupled from the gear reduction module <NUM> when the shift collar <NUM> is in the first position. For instance, the shift collar gear <NUM> may be spaced apart from and may not mate or mesh with the second gear portion <NUM> of the sun gear <NUM> or the planet gear carrier gear portion <NUM> of the planet gear carrier <NUM>. Accordingly, the electric motor module <NUM> may not provide torque to the drive pinion <NUM> or the auxiliary shaft <NUM> and may not receive torque from the drive pinion <NUM> or the auxiliary shaft <NUM>. The auxiliary device <NUM> may therefore provide torque to propel the vehicle and regenerative torque may not be provided to the electric motor module <NUM> when the vehicle is coasting.

In <FIG>, the shift collar <NUM> is shown in a second position. In the second position, the shift collar <NUM> may couple the drive pinion <NUM>, the planet gear carrier <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the planet gear carrier <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the second set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the planet gear carrier gear portion <NUM>. The second position may also be referred to as a low range position in which the gear reduction module <NUM> may provide a low range gear ratio. Accordingly, the auxiliary device <NUM> may provide torque to propel the vehicle and regenerative torque to the electric motor module <NUM> such that the electric motor module <NUM> may act as a generator that may charge the electrical power source. In addition, regenerative torque may be provided to the electric motor module <NUM> via the low range gear ratio when the vehicle is coasting.

In <FIG>, the shift collar <NUM> is shown in a third position. In the third position, the shift collar <NUM> may couple the drive pinion <NUM>, the sun gear <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the sun gear <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the first set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The third position may also be referred to as a high range position in which the gear reduction module <NUM> may provide a high range gear ratio as previously discussed. Accordingly, the auxiliary device <NUM> may provide torque to propel the vehicle and may provide regenerative torque to the electric motor module <NUM> such that the electric motor module <NUM> may act as a generator that may charge the electrical power source. In addition, regenerative torque may be provided to the electric motor module <NUM> via the high range gear ratio when the vehicle is coasting.

In <FIG>, the shift collar <NUM> is shown in a fourth position. In the fourth position, the shift collar <NUM> may couple the sun gear <NUM> of the gear reduction module <NUM> to the auxiliary shaft <NUM> such that the sun gear <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM> and the second set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The fourth position may also be a high range position in which the gear reduction module <NUM> may provide a high range gear ratio or the same gear ratio as the third position. The drive pinion <NUM> may be decoupled from the shift collar <NUM> when the shift collar <NUM> is in the fourth position. Accordingly, the auxiliary device <NUM> may not provide torque to propel the vehicle and may provide regenerative torque to the electric motor module <NUM> such that the electric motor module <NUM> may act as a generator that may charge the electrical power source. In addition, it is contemplated that shift collar <NUM> may be configured to provide regenerative torque to the electric motor module <NUM> via the low range gear ratio when the shift collar <NUM> is decoupled from the drive pinion <NUM>.

Referring to <FIG>, the auxiliary shaft <NUM> may be configured to function as an input and may receive torque from an auxiliary device <NUM>, such as an internal combustion engine. For instance, the auxiliary device <NUM> may be a torque source that is connected in a parallel hybrid configuration. The shift collar positions in <FIG> match those shown in <FIG>, but the torque transmission paths may differ.

In <FIG>, the shift collar <NUM> is shown in a second position. In the second position, the shift collar <NUM> may couple the drive pinion <NUM>, the planet gear carrier <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the planet gear carrier <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the second set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the planet gear carrier gear portion <NUM>. The second position may also be referred to as a low range position in which the gear reduction module <NUM> may provide a low range gear ratio. Accordingly, the electric motor module <NUM>, the auxiliary device <NUM>, or both may provide torque to propel the vehicle. In addition, regenerative torque may be provided to the electric motor module <NUM> via the low range gear ratio when the vehicle is coasting.

In <FIG>, the shift collar <NUM> is shown in a third position. In the third position, the shift collar <NUM> may couple the drive pinion <NUM>, the sun gear <NUM> of the gear reduction module <NUM>, and the auxiliary shaft <NUM> such that the drive pinion <NUM>, the sun gear <NUM>, the shift collar <NUM>, and the auxiliary shaft <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>, and the first set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The third position may also be referred to as a high range position in which the gear reduction module <NUM> may provide a high range gear ratio as previously discussed. Accordingly, the electric motor module <NUM>, the auxiliary device <NUM>, or both may provide torque to propel the vehicle. In addition, regenerative torque may be provided to the electric motor module <NUM> via the high range gear ratio when the vehicle is coasting.

In <FIG>, the shift collar <NUM> is shown in a fourth position. The fourth position in <FIG> may be the same as the fourth position and description associated with <FIG>.

Referring to <FIG>, the shift collar <NUM>' is shown with a different configuration than the shift collar <NUM> previously discussed. In the configuration shown, the shift collar gear <NUM> of the shift collar <NUM>' may include a third set of teeth <NUM> in addition to the first set of teeth <NUM> and the second set of teeth <NUM>. The second set of teeth <NUM> may be positioned between the first set of teeth <NUM> and the third set of teeth <NUM>. A second annular groove <NUM> may be provided between the second set of teeth <NUM> and the third set of teeth <NUM>. The second annular groove <NUM> groove may extend around the first axis <NUM> and may separate the second set of teeth <NUM> from the third set of teeth <NUM>. In <FIG>, the auxiliary shaft <NUM> is configured to function as an output or power take-off and may be operatively connected to at least one auxiliary device <NUM> at previously discussed. In addition, the shift collar <NUM>' may be configured to selectively couple the gear reduction module <NUM> to the drive pinion <NUM> or the auxiliary shaft <NUM> in <FIG>, which may differ from the configurations shown in <FIG> in which the shift collar <NUM> remains coupled to the auxiliary shaft <NUM>.

In <FIG>, the shift collar <NUM>' is shown in a first neutral position. The shift collar <NUM>' may be coupled to the drive pinion <NUM> such that the shift collar <NUM>' and the drive pinion <NUM> may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>. The shift collar <NUM>' may be decoupled from the gear reduction module <NUM> and may be decoupled from the auxiliary shaft <NUM> when the shift collar <NUM>' is in the first neutral position. For instance, the shift collar gear <NUM> may be spaced apart from and may not mate or mesh with the first gear portion <NUM> of the sun gear <NUM> or the planet gear carrier gear portion <NUM> of the planet gear carrier <NUM>, and the second shift collar spline <NUM> may be spaced apart from and may not mate or mesh with the auxiliary shaft spline <NUM>. The drive pinion <NUM> and the shift collar <NUM>' may rotate about the first axis <NUM> when the vehicle is coasting and torque is provided from the rotating vehicle wheels to the drive pinion <NUM> via the axle shafts <NUM> and the differential assembly <NUM>.

In <FIG>, the shift collar <NUM>' is shown in a low range position. The shift collar <NUM>' may couple the drive pinion <NUM> to the planet gear carrier <NUM> of the gear reduction module <NUM> such that the drive pinion <NUM>, the planet gear carrier <NUM>, and the shift collar <NUM>' may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, and the third set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the planet gear carrier gear portion <NUM>. The gear reduction module <NUM> may provide a low range gear ratio in the low range position. The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM>, the sun gear <NUM> may provide torque to the planet gear carrier <NUM> via the planet gears <NUM>, and the planet gear carrier <NUM> may provide torque to the drive pinion <NUM> via the shift collar <NUM>' when the shift collar is in the low range position and the electrical power source provides electrical power to the electric motor module <NUM>. The shift collar <NUM>' may be decoupled from the auxiliary shaft <NUM> and the sun gear <NUM> when the shift collar <NUM>' is in the low range position.

In <FIG>, the shift collar <NUM>' is shown in a high range position. The shift collar <NUM>' may couple the drive pinion <NUM> to the sun gear <NUM> of the gear reduction module <NUM> such that the drive pinion <NUM>, the sun gear <NUM>, and the shift collar <NUM>' may be rotatable together about the first axis <NUM>. For example, the first shift collar spline <NUM> may mate or mesh with the drive pinion spline <NUM>, and the first set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM>. The gear reduction module <NUM> may provide a high range gear ratio in the high range position. The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM>, and the sun gear <NUM> may provide torque to the drive pinion <NUM> via the shift collar <NUM>' when the shift collar is in the high range position and the electrical power source provides electrical power to the electric motor module <NUM>. The shift collar <NUM>' may be decoupled from the auxiliary shaft <NUM> and the planet gear carrier <NUM> when the shift collar <NUM>' is in the high range position.

In <FIG>, the shift collar <NUM>' is shown in a second neutral position. The shift collar <NUM>' may be coupled to the sun gear <NUM> such that the shift collar <NUM>' and the sun gear <NUM> may be rotatable together about the first axis <NUM>. For example, the second set of teeth <NUM> of the shift collar <NUM>' may mate or mesh with the sun gear spline <NUM> of the sun gear <NUM>. The shift collar <NUM>' may be decoupled from the drive pinion <NUM> and may be decoupled from the auxiliary shaft <NUM> when the shift collar <NUM>' is in the second neutral position. For instance, the first shift collar spline <NUM> may be spaced apart from and may not mate or mesh with the drive pinion spline <NUM> and the second shift collar spline <NUM> may be spaced apart from and may not mate or mesh with the auxiliary shaft spline <NUM> of the auxiliary shaft <NUM>.

In <FIG>, the shift collar <NUM>' is shown in an auxiliary drive position. The shift collar <NUM>' may couple the sun gear <NUM> of the gear reduction module <NUM> to the auxiliary shaft <NUM> such that the auxiliary shaft <NUM>, the sun gear <NUM>, and the shift collar <NUM>' may be rotatable together about the first axis <NUM>. For example, the third set of teeth <NUM> of the shift collar gear <NUM> may mate or mesh with the first gear portion <NUM> of the sun gear <NUM> and the second shift collar spline <NUM> may mate or mesh with the auxiliary shaft spline <NUM>. The electric motor module <NUM> may provide torque to the sun gear <NUM> via the rotor shaft <NUM>, and the sun gear <NUM> may provide torque to the auxiliary shaft <NUM> via the shift collar <NUM>' when the shift collar <NUM>' is in the auxiliary drive position and the electrical power source provides electrical power to the electric motor module <NUM>. The shift collar <NUM>' may be decoupled from the drive pinion <NUM> and the planet gear carrier <NUM> when the shift collar <NUM>' is in the auxiliary drive position.

Claim 1:
A drivetrain system (<NUM>) comprising:
an axle assembly (<NUM>) that includes:
an electric motor module (<NUM>) that has a rotor (<NUM>) that is rotatable about a first axis (<NUM>);
a gear reduction module (<NUM>) that is operatively connected to the electric motor module (<NUM>);
a drive pinion (<NUM>) that is rotatable about the first axis (<NUM>);
a differential assembly (<NUM>) that is rotatable about a second axis (<NUM>) and engages the drive pinion (<NUM>); the drivetrain system being characterized in that the axle assembly further includes
an auxiliary shaft (<NUM>) that is rotatable about the first axis (<NUM>) and is spaced apart from the drive pinion (<NUM>); and
a shift collar (<NUM>) that is rotatable about the first axis (<NUM>) with the auxiliary shaft (<NUM>) and selectively couples the auxiliary shaft (<NUM>) to the drive pinion (<NUM>), the gear reduction module (<NUM>), or the drive pinion (<NUM>) and the gear reduction module (<NUM>).