DESCRIPTION

TECHNICAL FIELD

[0001] The present disclosure relates to a modular powertrain for a vehicle, and more particularly to powertrains for vehicles that may contain a number of different configurations of similar components, or even common components, suited for typical vocations of a particular vehicle.

BACKGROUND

[0002] Many vehicles now utilize hybrid-electric powertrains in order to increase the efficiency of the vehicle. Hybrid-electric powertrains typically improve overall vehicle fuel efficiency by supplementing an internal combustion engine with electric motors, such that less power output is required of the internal combustion engine, as power from the electric motors may also be utilized in situations when maximum powertrain output is required, such as acceleration, or climbing a grade. Additionally, hybrid-electric powertrains may be utilized to power equipment mounted to a vehicle, such as, for example, a lift, an auger, a post hole digger, a crane, or other known equipment that may be utilized when a vehicle is not in motion. Such power equipment may be powered through a power take off ("PTO") that may be driven by electric motors of the hybrid-electric powertrain to reduce the time an internal combustion engine is operated. For instance, if torque required to operate the equipment mounted to the vehicle is generally low, or the equipment is only used intermittently, it is contemplated that only the electric motors may be utilized. However, if the torque demand of the equipment is high, or the equipment is used for a prolonged period, the internal combustion engine may be used in place of, or in addition to, the electric motors to power the equipment.

[0003] However, as individual vehicles are typically used for specific tasks,

particularized powertrains well suited for those specific tasks ideally would be placed in the individual vehicles. However, while such an arrangement may allow for more economical operation by the vehicle while performing that specific task, manufacturing costs associated with producing a plurality of particularized powertrains may be higher. Limited build volumes of certain powertrains result in high component costs, increasing vehicle costs above a price point users are willing to pay. Additionally, low build volumes can complicate manufacturing, as assembly line workers are utilizing different components for each vehicle. [0004] Therefore, a need exists for a modular powertrain that utilizes combinations of common components in order to provide particularized powertrains for specific vehicle configurations.

SUMMARY

[0005] According to one embodiment, a vehicle having a modular powertrain comprises at least one electric motor, a torque transferring assembly, and a driveline assembly. The torque transferring assembly couples to the at least one electric motor to receive torque generated by the at least one electric motor. The driveline assembly couples to the torque transferring assembly to receive torque from the torque transferring assembly.

[0006] According to another embodiment, a modular hybrid-electric powertrain for a vehicle comprises an internal combustion engine, a first electric motor, a torque transferring assembly, and a driveline assembly. The torque transferring assembly couples to at least one of the first electric motor and the internal combustion engine to receive torque generated by the at least one of the first electric motor and the internal combustion engine. The driveline assembly couples to the torque transferring assembly to receive torque from the torque transferring assembly.

[0007] According to one process, a method of forming a modular hybrid-electric powertrain is provided. An internal combustion engine and a torque transferring assembly are provided. The torque transferring assembly connects to a driveline assembly. At least one of a first electric motor and a clutch are selected to couple to the internal combustion engine. The selected first electric motor and the clutch couple to the internal combustion engine. At least one of the first electric motor and a second electric motor are selected to couple to the torque transferring assembly. The selected first electric motor and the second electric motor couple to the torque transferring assembly.

BRIEF DESCRIPTION OF THE DRAWINGS

[0008] FIG. 1 is an exploded schematic diagram showing a vehicle having a modular hybrid-electric powertrain.

[0009] FIG. 2 is a schematic diagram showing a vehicle having a modular integrated starter generator hybrid-electric powertrain.

[0010] FIG. 3 is a schematic diagram showing a vehicle having a modular parallel hybrid-electric powertrain. [0011] FIG. 4 is a schematic diagram showing a vehicle having a modular compound hybrid-electric powertrain.

[0012] FIG. 5 is a schematic diagram showing a vehicle having a modular electric powertrain.

[0013] FIG. 6 is a schematic diagram showing a vehicle having a modular series hybrid- electric powertrain.

DETAILED DESCRIPTION

[0014] Referring now to the figures and in particular to FIG. 1, an exploded schematic diagram of a vehicle having a modular hybrid-electric powertrain 10 is depicted. The modular hybrid-electric powertrain 10 comprises an internal combustion engine 12. The internal combustion engine 12 may be a diesel engine, or a gasoline engine. It is

contemplated that when the modular hybrid-electric powertrain 10 is utilized in a commercial truck, that the internal combustion engine 12 is a diesel engine. A flywheel 14 is connected to an output shaft, such as a crankshaft of the internal combustion engine 12. The flywheel 14 is contained within a flywheel housing 16. The flywheel housing 16 may have a Society of Automotive Engineers (SAE) No. 1 or a SAE No. 2 interface.

[0015] The modular hybrid-electric powertrain 10 additionally comprises a first electric motor 18. The first electric motor 18 may be an electric motor and generator, in that the first electric motor 18 may be operated in a first mode to generate electrical power by receiving torque from the internal combustion engine 12. The first electric motor 18 may also be operated in a second mode to produce torque using electrical power from a stored source, such as a battery. A flexplate 20 may be utilized to connect an input shaft 22 from the flywheel 14 to the first electric motor 18. The first electric motor 18 may also connect to a flywheel 24 via an output shaft. The first electric motor 18 will have an interface at an end generally abutting the flywheel housing 16 to match the SAE No.1 or SAE No. 2 interface of the flywheel housing 16, such that the first electric motor 18 and the flywheel housing 16 are connected.

[0016] A clutch 26 is disposed adjacent to the first electric motor 18 in the modular hybrid-electric powertrain 10. The clutch 26 is contained within an adapter ring 28. The adapter ring 28 structurally connects the clutch 26 to the first electric motor 18 and allows the clutch 26 to selectively engage the flywheel 24 of the first electric motor 18. The adapter ring 28 will have a SAE No. 1 or SAE No. 2 interface that matches the adjacent interface of the first electric motor 18. [0017] The modular hybrid-electric powertrain 10 additionally comprises a second electric motor 30. The second electric motor 30 is a traction motor, in that it is adapted simply to provide power used to move the vehicle having the modular hybrid-electric powertrain 10. An input shaft 32 from the clutch 26 is connected to the second electric motor. The input shaft 32 allows the clutch 16 to supply torque from the internal combustion engine 12 and the first electric motor 18 to a flywheel 34 connected to the input shaft 32. Thus, the flywheel 34 is capable of receiving torque from the second electric motor 30, the first electric motor 18, and the internal combustion engine 12. The second electric motor 30 has an interface at an end generally abutting the adapter ring 28 that matches the SAE No. 1 or SAE No. 2 interface of the adapter ring 28.

[0018] A tail shaft assembly 36 is also comprised by the modular hybrid-electric powetrain 10. The tail shaft assembly 36 comprises a transmittal shaft 38 and a flexplate 40. The flexplate 40 of the tail shaft assembly 36 connects to the flywheel 34 of the second electric motor 30. The flexplate 40 mounts on the transmittal shaft 38, thus the transmittal shaft 38 receives torque from the second electric motor 30, and may receive torque from the first electric motor 18 and the internal combustion engine 12, depending on engagement of the clutch 26, and transfers the torque through the tail shaft assembly 36. The tail shaft assembly 36 has an interface at an end generally abutting the second electric motor 30 that matches the SAE No. 1 or SAE No. 2 interface of the second electric motor 30. The tail shaft assembly 36 additionally comprises an output shaft 42.

[0019] The modular hybrid-electric powertrain 10 additionally comprises a driveline assembly 44. The driveline assembly 44 is known in the art and comprises a driveshaft, a differential gear, at least one axle, a suspension system, and a plurality of wheels. The driveline assembly 44 couples to the transmittal shaft 38 of the tail shaft assembly 36 to receive torque from at least one of the internal combustion engine 12, the first electric motor 18, and the second electric motor 30 to move the vehicle having the modular hybrid-electric powertrain 10.

[0020] The input shaft 22, the input shaft 32, and the transmittal shaft 38 may have a plurality of splines in order to transmit torque. The shafts 22, 32, 38 may have a diameter of from about 1.5 inches to about 2.25 inches, but more particularly have a diameter of about 1.75 inches to about 2 inches.

[0021] Turning now to FIG. 2, a schematic diagram of a modular powertrain 50 is shown. The modular powertrain 50 is an integrated starter generator powertrain, in that the first electric motor 18 is utilized to generate electrical power, and also as a starter for the internal combustion engine 12. Torque generated by the internal combustion engine 12 is transmitted through a torque converter or a clutch 46 to a transmission 48. The torque converter or clutch 46 is typically a torque converter if the transmission 48 is an automatic transmission, while the torque converter or clutch 46 is typically a clutch if the transmission 48 is a manual transmission. The transmission 48 typically has a plurality of gears or ranges in order to allow the internal combustion engine 12 to maintain an operating speed suited to move the vehicle. It is also contemplated that the transmission 48 may be a continuously variable transmission. The torque converter or clutch 46 and the transmission 48 are known in the art. The transmission 48 is coupled to the driveline assembly 44 to provide torque to move a vehicle having the modular powertrain 50. The torque provided to the driveline assembly 44 of the modular powertrain 50 is supplied only from the internal combustion engine 12.

[0022] FIG. 3 shows a modular hybrid-electric powertrain 60. The modular hybrid- electric powertrain 60 is a pre-transmission parallel type hybrid-electric powertrain. The modular hybrid-electric powertrain 60 comprises the internal combustion engine 12, the clutch 26, the first electric motor 18, the torque converter or clutch 46, the transmission 48, and the driveline assembly 44. The clutch 26 selectively connects the internal combustion engine 12 to the first electric motor 18, such that the torque converter or clutch 46 may receive torque from at least one of the internal combustion engine 12, the first electric motor 18, or both the internal combustion engine 12 and the first electric motor 18. For instance, in certain operating conditions, such as at low speeds, the torque converter or clutch 46 may only receive torque from the first electric motor 18, while at other operating conditions, such as at highway speeds, the torque converter or clutch 46 may only receive torque from the internal combustion engine 12, while at still other operating conditions, such as during rapid acceleration, the torque converter or clutch 46 may receive torque from both the internal combustion engine 12 and the first electric motor 18. The torque received by the torque converter or clutch 46 is then transmitted to the transmission 48 and then to the driveline assembly 44.

[0023] Turning now to FIG. 4, the modular hybrid-electric powertrain 10 is shown in an assembled state. The modular hybrid-electric powertrain 10 is a compound type hybrid- electric powertrain. The modular hybrid-electric powertrain 10 comprises the internal combustion engine 12, the first electric motor 18, the clutch 26, the second electric motor 30, the tail shaft assembly 36 and the driveline assembly 44. The first electric motor 18 is typically used as a generator to produce electrical energy for use by the second electric motor 30. The clutch 26 selectively connects the internal combustion engine 12 to the second electric motor 30, such that the tail shaft assembly 36 may receive torque from at least one of the internal combustion engine 12, the second electric motor 30, or both the internal combustion engine 12 and the second electric motor 30. For instance, in certain operating conditions, such as at low speeds, the tail shaft assembly 36 may only receive torque from the second electric motor 30, while at other operating conditions, such as at highway speeds, the tail shaft assembly 36 may only receive torque from the internal combustion engine 12, while at still other operating conditions, such as during rapid acceleration, the tail shaft assembly 36 may receive torque from both the internal combustion engine 12 and the second electric motor 30. The torque received by the tail shaft assembly 36 is then transmitted to the driveline assembly 44.

[0024] FIG. 5 shows a modular electric powertrain 70. The electric powertrain 70 comprises the second electric motor 30, the tail shaft assembly 36, and the driveline assembly 44. The electric powertrain 70 only utilizes electrical energy to move a vehicle. The second electric motor 30 receives electrical energy from a battery pack, not shown, and provides torque to the tail shaft assembly 36 and to the driveline assembly 44. The electric powertrain 70 is typically used in vehicles that do not travel far, such as vehicles used in freight yards, or within factories, or shipping facilities, where a battery pack could be charged on a regular basis. It is contemplated as battery pack technology allows for longer operating ranges, a vehicle with the electric powertrain 70 could also be utilized for over-the-road trucking operations.

[0025] Finally, FIG. 6 depicts a modular hybrid-electric powertrain 80. The modular hybrid-electric powertrain 80 is a series type hybrid-electric powertrain. The modular hybrid-electric powertrain 80 comprises the internal combustion engine 12, the first electric motor 18, the second electric motor 30, the tail shaft assembly 36 and the driveline assembly 44. The first electric motor 18 is used as a generator powered by the internal combustion engine 12 to produce electrical energy for use by the second electric motor 30. The tail shaft assembly 36 only receives torque from the second electric motor 30. Thus, the internal combustion engine 12 is only used to operate the first electric motor 18 as a generator. The tail shaft assembly 36 only receives torque from the second electric motor 30, regardless of vehicle operating conditions. The torque received by the tail shaft assembly 36 is then transmitted to the driveline assembly 44.

[0026] Thus, as may be seen by FIGs. 2-6 the modular powertrains 10, 50, 60, 70, 80 allow a plurality of components to be arranged in a variety of manners to form different types of powertrains. Thus, by using common components between the various modular powertrains 10, 50, 60, 70, 80, such as the internal combustion engine 12, the first electric motor 18, the second electric motor 30, the clutch 26, the tail shaft assembly 36, and the driveline assembly 44, the torque converter or clutch 46 and the transmission 48, the components may be selected and arranged to form a variety of types of powertrains, thereby increasing the volume use of the components, and allowing a variety of powertrains to be created without the need to engineer specific components for each variety of powertrain. The torque converter or clutch 46 and the transmission 48 or the tail shaft assembly 36 act as a torque transfer assembly to transfer torque from a power source, such as the internal combustion engine 12 and/or the second electric motor 30 to the driveline assembly 44.

[0027] The use of SAE No. 1 and/or SAE No. 2 interfaces on the various components of the powertrains 10, 50, 60, 70, 80 allows the components to readily be assembled in a variety of arrangements.