Dual clutch powertrain architecture

A powertrain architecture includes an engine and a transmission coupled through a launch device that is configured to be selectively mechanically coupled to the engine and to the transmission. A ring gear is positioned at least partially around the launch device. An engine lock up clutch mechanically couples the engine to the ring gear. A turbine lock up clutch mechanically couples the launch device to the ring gear. Ancillary devices are provided to receive power from or transmit power to the ring gear. The engine lock up clutch and the turbine lock up clutch selectively engage the ring gear to power at least one ancillary device.

TECHNICAL FIELD OF THE DISCLOSED EMBODIMENTS

The embodiments disclosed herein related to a powertrain architecture and, more particularly, to a dual clutch system for a powertrain architecture.

BACKGROUND OF THE DISCLOSED EMBODIMENTS

Vehicle powertrain systems are being designed to increase fuel economy and reduce carbon emissions. Hybrid engines are being incorporated into many vehicles to accomplish these tasks. Unfortunately, the market is currently rejecting many hybrid vehicle models because the vehicles provide little return on investment. Particularly, many of these models incorporate recovered energy systems. Recovered energy systems are difficult and expensive to integrate into the vehicle. As a result, the costs of hybrid vehicles are significantly higher than the cost of an equivalent non-hybrid make and model. Additionally, hybrid systems are difficult to maintain, which further increases the costs associated with owning a hybrid. The expenses associated with purchasing and maintaining a hybrid vehicle typically arc not offset by the reduction of fuel costs associated with the increased fuel economy of the hybrid vehicle,

There are several possible energy sources within a. vehicle, Fuel energy and low voltage energy systems are the most common sources of energy to power the vehicle. However, these sources increase the fuel consumption of the vehicle. Currently, the automotive industry is shifting away from relying on fuel energy to accomplish increased fuel economy. Recovered energy systems, as described above, effectively reduce fuel consumption, but do so at an increased cost of manufacturing and maintenance. An additional source of power within the vehicle comes from the kinetic and potential energy of the vehicle, i.e. energy created by the rotation of the vehicle's wheels when power from the transmission is not being applied to the wheels. Most vehicles fail to capture the kinetic and potential energy of the vehicle and this energy generally goes to waste.

SUMMARY OF THE DISCLOSED EMBODIMENTS

In one embodiment, a powertrain architecture includes an engine and a launch device having a turbine configured to be selectively mechanically coupled to the engine to receive power from the engine. A ring gear is positioned around the launch device. An engine lock up clutch mechanically couples the engine to the ring gear. A turbine lock up clutch mechanically couples the turbine of the launch device to the ring gear. Ancillary devices at least one of receive power from or transmit power to the ring gear. The engine lock up clutch and the turbine lock up clutch selectively engage the ring gear to power at (east some of the ancillary devices.

In one embodiment, a dual lock up clutch is provided. The dual lock up clutch includes a ring gear positioned around a launch device. An engine lock up clutch mechanically couples an engine of the powertrain architecture to the ring gear. A turbine lock up clutch mechanically couples a turbine of the launch device to the ring gear. Ancillary devices at least one of receive power from or transmit power to the ring gear. The engine lock up clutch and the turbine lock up clutch selectively engage the ring gear to power at least some of the ancillary devices.

In one embodiment, a method of powering ancillary devices of a vehicle is provided. The method includes providing a ring gear positioned around a launch device of the vehicle. An engine lock up clutch is provided to mechanically couple an engine to the ring gear. A turbine lock up clutch is provided to mechanically couple a turbine of the launch device to the ring gear. The method also includes selectively engaging the engine lock up clutch and the turbine lock up clutch to the ring gear to power at least some of ancillary devices of the vehicle.

Other embodiments are also disclosed.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS

The features and advantages of this disclosure, and the manner of attaining them, will be more apparent and better understood by reference to the following descriptions of the disclosed methods and systems, taken in conjunction with the accompanying drawings. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the disclosure. Moreover, in the figures like referenced numerals designate corresponding parts throughout the different views, but not all reference numerals are shown in each of the figures.

For the purposes of promoting an understanding of the principles of the present disclosure, reference will now be made to the embodiments illustrated in the drawings, and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of this disclosure is thereby intended. Alterations and modifications in the illustrated device, and further applications of the principles of the invention as illustrated therein, as would normally occur to one skilled in the art to which the invention relates are contemplated, are desired to be protected. Such alternative embodiments require certain adaptations to the embodiments discussed herein that would be obvious to those skilled in the art.

Disclosed herein is a powertrain architecture for a vehicle, wherein the architecture includes an engine and a transmission coupled through a launch device configured to be selectively mechanically coupled to the engine and to the transmission, in one embodiment, the launch device comprises a torque converter having an impeller that is mechanically coupled to the engine and a turbine that is mechanically coupled to the transmission. A ring gear is positioned around the launch device. It should be noted that in other embodiments, the ring gear may be replaced with a belt system, a chain drive, or any other suitable mechanism for coupling to the engine and/or the transmission. An engine lock up clutch selectively mechanically couples the engine to the ring gear, and a turbine lock up clutch selectively mechanically couples the turbine of the launch device to the ring gear. In one embodiment, the transmission may be coupled to the ring gear via a countershaft. Alternatively, the transmission may be coupled to the ring gear via an output shaft. Ancillary devices receive power from or transmit power to the ring gear. The engine lock up clutch and the turbine lock up clutch selectively engage the ring gear to power at least some of the ancillary devices. In one embodiment, during a driving operation, the engine lock up clutch and the turbine lock up clutch are both mechanically coupled to the ring gear to transmit power from the engine to the ancillary devices and to the transmission. In one embodiment, during an engine on at stop operation, the engine lock up clutch mechanically couples the engine to the ring gear and the turbine lock up clutch is decoupled from the ring gear to transmit power from the engine to the ancillary devices, but not to the transmission. In one embodiment, during an engine off at stop operation, the engine lock up clutch and the turbine lock up clutch are decoupled from the ring gear so that power from a low voltage energy storage may be transmitted through the ring gear to the ancillary devices. In one embodiment, during an engine, off at speed operation, the engine lock up clutch is decoupled from the ring gear and the turbine lock up clutch mechanically couples the transmission to the ring gear to transmit kinetic energy from the wheels, through the transmission, and to the ancillary devices. In one embodiment, the potential energy of the vehicle is converted to kinetic energy in the wheels and transmitted through the transmission and the ring gear to the ancillary devices. In one embodiment, a stationary electric Power Takeoff (PTO) mode may be utilized, wherein the system runs the ring in neutral powered by an electrical auxiliary power source (fuel cell) for stationary AC and mild hydraulic power.

In one embodiment, the ancillary devices include an input accessory motor mechanically coupled to the ring gear, a low voltage energy storage electrically coupled to the input accessory motor, low voltage electronics electrically coupled to the low voltage energy storage, and a turbocharger motor and an exhaust system heater electrically coupled to the input accessory motor and to the low voltage energy storage. In such an embodiment, during an acceleration operation, the engine lock up clutch and the turbine lock up clutch mechanically couple the engine and the transmission to the ring gear to transmit power from the engine to the transmission and the ancillary devices. During a cruise operation, the engine lock up clutch and the turbine lock up clutch mechanically couple the engine and the transmission to the ring gear to transmit power from the engine to the transmission and the ancillary devices, The cruise operation further transmits power from the turbocharger motor to the to the transmission. During an engine off while moving operation, the turbine lock up clutch mechanically couples the transmission to the ring gear and the engine lock up clutch is decoupled from the ring gear to transmit kinetic energy from the transmission to the low voltage electronics and the exhaust system heater via the input accessory motor. The engine off while moving operation further transmits kinetic energy from the transmission to the ancillary devices.

FIG. 1is a schematic view of a powertrain architecture10having an engine12, a launch device14, and transmission16. The engine12may be any suitable engine for powering a vehicle (not shown), for example, a truck, a bus, an automobile, or the like. The engine12includes a crankshaft48and a flywheel46that are caused to rotate by combustion within the engine12. An output shaft18of the engine12is mechanic-ally coupled to the launch device14, In an exemplary embodiment, the launch device14is a torque converter used to transfer rotating power from the engine12to the transmission16. An impeller20of the torque converter is mechanically coupled to the engine12. and a turbine22of the torque converter is mechanically coupled to the transmission16, as is known in the art. In particular, an input shaft24of the transmission16is mechanically coupled to turbine22to receive power therefrom during normal powered operation of the powertrain10, whereby the engine12delivers power to the transmission36and the transmission16delivers the power to a driveline output52that is coupled to wheels (not shown) of the vehicle.

A ring gear26at least partially surrounds the launch device14. The ring gear26is mechanically coupled to a plurality of ancillary devices. The ancillary devices include, but are not limited to, a transmission pump30, an air brake compressor32, a power steering pump34, and an HVAC compressor36. Additionally, the ancillary devices include an input accessory motor38mechanically coupled to the ring gear26. A low voltage energy storage40, for example a battery, is electrically coupled to the input accessory motor38. Each of the ancillary devices may be independently clutched in some embodiments to enable selective operation of the devices. In one embodiment, the input accessory motor38may be an insulated gate bipolar transistor 3-phase motor. Alternatively, the input accessory motor38may be replaced by a full hybrid system. Low voltage electronics42within the vehicle are powered by the low voltage energy storage40.

A pair of lock up clutches are configured to selectively engage the ring gear26to alter a power source for the low voltage electronics42and the ancillary devices. An engine lock up clutch44selectively mechanically couples the ring gear26to the flywheel46(or other appropriate portion) of the engine12, Additionally, a turbine lock up clutch50selectively mechanically couples the ring gear26to the turbine22of the launch device14(or other appropriate portion of the transmission). The embodiments described below illustrate the various configurations in which the low voltage electronics42and the ancillary devices are powered by the powertrain architecture10. A transmission electronic control module (not shown) may be utilized to control the engine lock up clutch44and the turbine lock up clutch50to select the power source of the powertrain architecture10. It will be appreciated that providing the ring gear26to power the ancillary devices eliminates the need for the accessory belt and starter ring included on the fore end of most prior art engines. Eliminating the accessory belt and starter ring from the system provides room within the vehicle package for the added components of the powertrain architecture10.

FIG. 2is a schematic illustration of the powertrain architecture10during an engine off at speed operation60. The engine off at speed operation60occurs when the vehicle is descending a grade but engine braking is not commanded (either automatically, such as when indicated by an inclinometer or, alternatively, manually by the operator of the vehicle). During the engine off at speed operation60, the engine lock up clutch44is decoupled from the ring gear26, and the turbine lock up clutch50is engaged to couple the transmission16to the ring gear26. In the engine off at speed operation60, kinetic energy from the transmission16is utilized to power the low voltage electronics42(through the input accessory motor38acting as a generator) and the vehicle ancillary devices, while the engine is off and uncoupled from the transmission16and from the vehicle ancillary devices, in particular, the rotation of the vehicle's wheels transmits kinetic energy to the transmission16, which thereby rotates the input shaft24of the transmission16. This energy is transmitted through the turbine22of the launch device14to the ring gear26(by operation of the turbine lockup clutch50), causing the ring gear26to rotate. The rotation of the ring gear26transmits the kinetic energy to the ancillary devices and the input accessory motor38as mechanical rotational energy. The rotation of the input accessory motor38thereby generates electrical power that is provided to the low voltage energy storage40. The power transmitted to the low voltage energy storage40may be stored therein and/or utilized to power the low voltage electronics42.

In the engine off at speed operation60, the fueling to the engine is stopped and the vehicle kinetic energy takes over as the vehicle power source. Uncoupling the engine12via the engine lockup clutch44eliminates engine losses that would otherwise use kinetic energy to cause rotation of the unfueled engine12. Because prior art systems do not have the ability to uncouple the engine from the launch device14, attempts have been made to minimize the drain on kinetic energy caused by rotating the unfueled engine by opening all of the engine valves. However, this causes cooling of the exhaust system and the concomitant requirement for additional fueling to heat the exhaust system components to meet exhaust emissions requirements, In the engine off at speed operation60, engine losses can be eliminated while not cooling the exhaust system. The engine off at speed operation60also provides complete controllability and meets all accessory load requirements, including driver comfort (e.g., operation of the HVAC compressor36).

FIG. 3is a schematic illustration of the powertrain architecture10during an engine off at stop operation62. During the engine off at stop operation62, the vehicle is stopped and the engine12is off; however, the low voltage electronics42and the ancillary devices are still powered by the low voltage energy storage40. The engine off at stop operation may also occur when an engine start/stop system is being used to save fuel and emissions by turning the engine12off when the vehicle comes to a stop, During the engine off at stop operation62, the engine lock up clutch44and the turbine lock up clutch50are both decoupled from the ring gear26. The low voltage energy storage40provides electrical current to the low voltage electronics42to power the low voltage electronics42while the engine12is turned off. Furthermore, the low voltage energy storage40provides electrical current to power the input accessory motor38. The input accessory motor38rotates the ring gear26to provide mechanical power to the transmission pump30. air brake compressor32, power steering34, and HVAC compressor36(and any other vehicle ancillary devices) so that these devices may be operational while the engine is turned off. It should be noted that other devices within the vehicle may be operated by the low voltage energy storage40during the engine off at stop operation62.

In some embodiments, the powertrain architecture10is in the engine off at stop operation62because an engine control module and/or transmission control module (not shown) have temporarily shut down the engine when the vehicle is not moving, such as at a stop light. There is often provision made for the driver to override the engine stop, which often happens because the vehicle HVAC compressor is not powered during engine stop in prior art systems. Accordingly, the ability in some of the presently disclosed embodiments to power the HVAC compressor36during the engine off at stop operation62reduces the incentive for the driver to override the engine stop, thereby increasing fuel efficiency and reducing exhaust emissions. The engine off at stop operation62also powers the transmission pump30, which allows for hill hold capability without a hill start assist system. Additionally, providing power to the power steering pump34prevents the typical “jerk” when the wheel is turned and the engine is stopped. Additionally, the driver is allowed to change wheel direction during the engine off at stop operation62, which would not be possible in some large vehicles such as buses using prior art systems.

In the engine off at stop operation62, the engine is started via the input accessory motor38. The prior art alternator, electric transmission pressure pump, and starter are all consolidated into one electric machine allowing the separate starter to he eliminated. Because the input accessory motor38is rotating, the ring gear26, the engine12may be started by coupling it to the ring gear26.

FIG. 4is a schematic illustration of the powertrain architecture10during an engine on at stop operation64. The engine on at stop operation64occurs when the vehicle is stopped and the engine12is fueled and running. During the engine on at stop operation64, the engine lock up clutch44is coupled to the ring gear26, and the turbine lock up clutch50is decoupled from the ring gear26. The engine12transmits power from the flywheel46to the ring gear26, thereby causing rotation of the ring gear26which mechanically powers the vehicle ancillary devices. The ring gear26additionally provides power to the input accessory motor38, which in turn generates electrical energy that is provided to the low voltage energy storage40. The low voltage energy storage40may store this power and/or utilize the power to electrically drive the low voltage electronics42. It will be appreciated that the transmission16, and hence the vehicle wheels, are uncoupled from the engine12during the engine on at stop operation64.

FIG. 5is a schematic illustration of the powertrain architecture10during a driving operation66. The driving operation66includes scenarios where the vehicle is accelerating, cruising, or climbing, or any other operation requiring the engine to be on and fueled. During the driving operation66, the engine lock up clutch44and the turbine lock up clutch50are both coupled to the ring gear26. Accordingly, the engine12transmits power to all of the devices of the vehicle. In particular, the engine12transmits power to the transmission16to drive the wheels of the vehicle via the driveline output52. Additionally, the engine12transmits power through the ring gear26to each of the ancillary devices and the low voltage electronics42via the input accessory motor38and the low voltage energy storage40. During the driving, operation66, the input accessory motor functions as a generator driven by the engine12.

A method70for operating the powertrain architecture10in various modes is illustrated inFIG. 6. The method70includes operating the powertrain architecture10in the engine off at stop operation62when the vehicle is stopped and the engine is not fueled, including the step72of decoupling the engine lock up clutch44and the turbine lock up clutch50from the ring gear26. In step74, power is transmitted from the low voltage energy storage40to power the low voltage electronics42, The low voltage energy storage40also powers the ancillary devices by causing the input accessory motor38to rotate the ring gear26to provide power to the ancillary devices, so that they may operate without power from the engine12. The method70also includes operating the powertrain architecture10in the driving operation66when the vehicle is accelerating, cruising, or climbing, or other situations in which the engine12is fueled, including the step76of coupling both the engine lock up clutch44and the turbine lock up clutch50to the ring gear26. In step78, power is transmitted from the engine12to ancillary devices, the low voltage electronics42, and the transmission16to allow the ancillary devices and electronics42to be powered by the engine12. The method70also includes operating the powertrain architecture10in the engine off at speed operation60when the vehicle is moving with the engine12unfueled, including the step80of coupling the turbine lock up clutch50to the ring gear26and the step82of decoupling the engine lock up clutch44from the ring gear26. At step84, kinetic energy of the vehicle are transmitted from the transmission16to the ancillary devices through the rotation of the ring gear26by the transmission16. The method70also includes operating the powertrain architecture10in the engine on at stop operation64, including the step86of coupling the engine lock up clutch44to the ring gear26and the step88of decoupling the turbine lock up clutch50from the ring gear26. At step90power is transmitted from the engine12to the ancillary devices through the ring gear26.

FIG. 7is a schematic illustration of another embodiment of a powertrain architecture110having an engine112, a launch device114, and transmission116. The engine112includes a crankshaft148and a flywheel146that are caused to rotate by combustion within the engine112, An output shaft118of the engine112is mechanically coupled to the launch device114. In an exemplary embodiment, the launch device114is a torque converter used to transfer rotating power from the engine112to the transmission116. An impeller120of the torque converter is mechanically coupled to the engine112, and a turbine122of the torque converter is mechanically coupled to the transmission116, as is known in the art. In particular, an input shaft124of the transmission116is mechanically coupled to turbine122to receive power therefrom during normal powered operation of the powertrain10, whereby the engine112delivers power to the transmission116and the transmission116delivers the power to a driveline output152that is coupled to wheels (not shown) of the vehicle.

A ring gear126at least partially surrounds the launch device114. The ring gear126is mechanically coupled to a plurality of ancillary devices. The ancillary devices include, but are not limited to, a transmission pump130, an air brake compressor132, a power steering pump134. and an HVAC compressor136. Additionally, the ancillary devices include an input accessory motor138mechanically coupled to the ring gear126. A low voltage energy storage140, for example a battery, is electrically coupled to the input accessory motor138. Low voltage electronics142within the vehicle are powered by the low voltage energy storage140. Additional ancillary devices, such as a turbocharger motor170, a turbocharger172, and an exhaust system heater174, are provided. The turbocharger motor170and the exhaust system heater174are electrically coupled to the low voltage energy storage140. The turbocharger172either is driven by the engine exhaust gas to rotate and turn the turbocharger motor170(thereby generating electricity that is stored in the low voltage energy storage140) or electricity in the low voltage energy storage140is used to drive the turbocharger motor170and thereby turn the turbocharger172to provide more airflow to the engine (in situations where the exhaust airflow is not high enough to operate the turbocharger172at the desired speed). The turbocharger172is configured to provide additional airflow to the engine112to increase a rate of combustion within the engine112, as is known in the art.

A pair of lock up clutches are configured to selectively engage the ring gear126to alter a power source for the low voltage electronics142and the vehicle ancillary devices. An engine lock up clutch144selectively mechanically couples the ring gear126to the flywheel146(or other appropriate portion) of the engine112. Additionally, a turbine lock up clutch150selectively mechanically couples the ring gear126to the turbine122of the launch device114(or other appropriate portion of the transmission). The embodiments described below illustrate the various configurations in which the low voltage electronics142mid the vehicle ancillary devices are powered by the powertrain architecture110. An electronic control system (not shown) is utilized to control the engine lock up clutch144and the turbine lock up clutch150to select the power source of the powertrain architecture110.

FIG. 8is a schematic illustration of an acceleration operation200of the powertrain architecture110. It will be appreciated from the discussion ofFIG. 8andFIG. 9below that in some embodiments the powertrain architecture110including a turbocharger172is operated in differing modes depending upon whether the vehicle is accelerating or cruising. In the acceleration operation200, the engine lock up clutch144and the turbine lock up clutch150are coupled to the ring gear126. The engine112powers the transmission116as well as the ancillary devices and the input accessory motor138. In the exemplary embodiment, the input accessory motor138and/or the low voltage energy storage140provides power to the low voltage electronics142as well as the turbocharger motor170. During acceleration of the vehicle, particularly from low rpm engine operating points, the turbocharger172may not be spinning last enough to generate the desired turbocharger boost. In such a situation, the low voltage energy storage140may be used to power the turbocharger motor170to drive the turbocharger172at a higher rpm, thereby generating additional turbocharger boost for the acceleration operation.

FIG. 9is a schematic illustration of a cruise operation202of the powertrain architecture110, In the cruise operation202, the engine lock up clutch144and the turbine lock up clutch150are coupled to the ring gear126and the vehicle is moving under power from the engine112, but is not accelerating above a predetermined threshold. The engine112powers the transmission116as well as the ancillary devices. However, in the cruise operation202, the input accessory motor138shifts from receiving power from the ring gear126to transmitting power to the ring gear126. In particular, the turbocharger motor170, driven by rotation of the turbocharger172by exhaust gases from the engine112, supplies power to the input accessory motor138, causing rotation of the input accessory motor which is then transmitted via the ring gear126. In the cruise, operation202, the rotational energy of the turbocharger172that is not needed to provide boost pressure to the engine112intake may be used to provide additional rotational power to the ring gear126.

FIG. 10is a schematic illustration of an engine off at speed operation160of the powertrain architecture110. The engine off at speed operation160occurs when the vehicle is descending a grade but engine braking is not commanded (either automatically, such as when indicated by an inclinometer or, alternatively, manually by the operator of the vehicle). In the engine off at speed operation160, the engine lock up clutch144is disengaged from the ring gear126and the turbine lock up clutch150engages the ring gear126to transmit kinetic energy from the transmission116to the vehicle ancillary devices and the input accessory motor138. The input accessory motor138, driven by the ring gear126, functions as a generator to send electrical power to the low voltage energy storage140and/or the exhaust system heater174. The exhaust system heater174is used to maintain the desired temperature of exhaust system components, such as a diesel particulate filter or a selective catalytic reduction (SCR) system, to name just two non-limiting examples. The exhaust system healer174may be needed when the engine112is not fueled and is therefore not producing hot exhaust gases that would otherwise maintain the desired temperature of the exhaust system.

A method180for operating the powertrain architecture110in various modes is illustrated inFIG. 11. The method180includes operating the powertrain architecture110in the acceleration operation200when the engine is fueled and the vehicle is accelerating, including the step182of coupling the engine lock up clutch144and the turbine lock up clutch150to the ring gear126. At step184, power is transmitted from the engine112to the transmission116and the ancillary devices, including the turbocharger motor170, The turbocharger motor170is used to drive the turbocharger172at a higher rpm, thereby generating additional turbocharger boost for the acceleration operation.

The method180also includes operating the powertrain architecture110in the cruise operation202when the vehicle is moving under power from the engine112, but is not accelerating above a predetermined threshold. The cruise operation202includes the step186of coupling the engine lock up clutch144and the turbine lock up clutch150to the ring gear126. At step188power is transmitted from the engine112to the transmission116the vehicle ancillary devices. At step190, power is also transmitted from the turbocharger motor170, driven by the turbocharger172, to the to the transmission116through the input accessory motor138and the ring gear126.

The method180also includes operating the powertrain architecture110in the engine off at speed operation160when the engine is off but engine braking is not commanded, including the step192of coupling the turbine lock up clutch150to the ring gear126and the step194of decoupling the engine lock up clutch144from the ring gear126, At step196kinetic energy are transmitted from the transmission116to the ancillary devices, low voltage electronics142and/or the exhaust system heater174to make up for the loss of heat from cessation of engine combustion exhaust gas flow.

FIG. 12schematically illustrates one embodiment of a ring gear assembly300that may be used to couple an engine302and a transmission304to a ring gear314. The ring gear assembly300may be used with either of the powertrain architectures30or110. A launch device306couples the engine302and the transmission304. The launch device306includes a torque converter308that is configured to couple to the engine302and the transmission304through the turbine312. The torque converter308and a transmission pump310are positioned within the ring gear314. An engine lock up clutch316is configured to selectively couple the engine302to the ring gear314. A turbine lock up clutch318is configured to selectively couple, the turbine312to the transmission pump310and the ring gear314. Ring gear driven accessories320are joined to the ring gear314using intermeshed gears.

During operation, the engine lock up clutch316couples the engine302to the ring gear314to start the powertrain architecture with ail ancillary devices being operational. The powertrain architecture is launched by the torque converter308until a torque converter lock up mode is required. At this time, the turbine lock up clutch318couples the transmission304to the ring gear314to provide a fixed gear transmission. When the vehicle slows down or stops, the engine lock up clutch316decouples the engine302from the ring gear314and the turbine lock up clutch318decouples the transmission304from the ring gear314. The engine302and the transmission304are stopped at zero revolutions per minute (RPM). The ring gear314continues to rotate to provide power to the ancillary devices via the input accessory motor. The ring gear314also provides hydraulic system pressure to the transmission304via the transmission pump310. The hydraulic system pressure enables the transmission304to be restarted from zero RPMs when the vehicle begins moving again and the turbine lock up clutch318couples the transmission304to the ring gear314.

The ring gear assembly300takes into account limited space within the powertrain architecture. Accordingly, the torque converter308is positioned within the ring gear314to limit the length of the powertrain architecture.

FIG. 13schematically illustrates another embodiment of a ring gear assembly400that may be utilized when the length of the powertrain architecture is not a limiting design factor. The ring gear assembly400couples an engine402and a transmission404to a ring gear414. The ring gear assembly400may be used with either of the powertrain architectures10or110. A launch device406couples the engine402and the transmission404. The launch device406includes a torque converter408that is configured to couple to the engine402and the transmission404through the turbine412. Because the length of the powertrain architecture is not a limiting design factor, the torque converter408is positioned outside of the ring gear414. This positioning enables the ring gear414to be sized so as to maintain a desired diameter ratio between the ring gear414and other gears within the powertrain architecture. A transmission pump410is positioned within the ring gear414and is powered by the rotation of the ring gear414. An engine lock up clutch416is configured to selectively couple the engine402to the ring gear414via the torque converter408. A turbine lock up clutch418is configured to selectively couple the turbine412to the pump410and the ring gear414. Ring gear driven accessories420are joined to the ring gear414.

FIG. 14schematically illustrates a ring gear assembly500used to couple an engine502and a transmission504to a ring gear514. The ring gear assembly500may be used with either of the powertrain architectures10or110. The ring gear assembly500illustrates an embodiment, wherein the torque converter may be replaced by another suitable launch device. The launch device506, for example a variator to name one non-limiting example, couples the engine502and the transmission504. The launch device506is positioned within the ring gear514. An engine lock up clutch516is configured to selectively couple the engine502to the ring gear514. A turbine lock up clutch518is configured to selectively couple the transmission504to the ring gear514. Ring gear driven accessories520are joined to the ring gear514.

The powertrain architecture10or110can be integrated with a wide range of power and energy levels and with multiple motor sizes. The powertrain architectures10and110provide the ability to recover waste energy and put that energy to use by, variously, mechanically driving accessory devices, generating electricity to drive accessory devices, and/or generating electricity to be stored. The powertrain architectures10and110optimize the usage of vehicle potential energy, kinetic energy, waste energy, and low voltage system energy to achieve improvements in fuel economy, efficiency and emissions reduction. The waste energy electricity is used to offset electrical accessory loads and to reduce the power taken from the powertrain by the input accessory motor, to add power to the transmission accessory power shaft to offset system hydraulic accessory loads, and to blend power with the engine output power in order to boost powertrain efficiency. Accordingly, the systems and methods disclosed herein recover vehicular waste energy and deliver it back into vehicle propulsion, reduced emissions, and fuel efficiency.

While this disclosure has been described using disclosed embodiments, the systems and methods according to the present disclosure can be further modified within the scope and spirit of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the disclosure using its general principles. For example, the methods disclosed herein and in the appended claims represent one possible sequence of performing the steps thereof. A practitioner may determine in a particular implementation that a plurality of steps of one or more of the disclosed methods may be combinable, or that a different sequence of steps may be employed to accomplish the same results. Each such implementation tails within the scope of the present disclosure as disclosed herein and in the appended claims. Furthermore, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this disclosure pertains and which fell within the limits of the appended claims.