초록 ▼

A vehicle drivetrain can include various structures, such as a multi-ratio transmission, a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio, a pair of front driveshafts driven by the tw

A vehicle drivetrain can include various structures, such as a multi-ratio transmission, a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio, a pair of front driveshafts driven by the two-speed final drive assembly, a pair of rear driveshafts, a rear differential assembly connected to the two-speed final drive assembly, and a control assembly including. The control assembly can include a controller in electrical communication with portions of the rear differential assembly, such as a variable displacement pump and purge valve. An input array can be in electrical communication with the controller and can include a plurality of sensors, and at least one switch accessible to an operator of the vehicle. Various related methods can also be executed for control and operation of such a drivetrain. The methods can incorporate a number of variables in order to control the drivetrain, and the variables can include but are not limited to road grade, vehicle acceleration, vehicle speed, presence of towing apparatus, road surface conditions, switch condition(s), etc.

대표청구항 ▼

1. A drivetrain for a vehicle comprising: a multi-ratio transmission;a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio;a pair of front driveshafts driven by the two-speed final drive a

1. A drivetrain for a vehicle comprising: a multi-ratio transmission;a two-speed final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio;a pair of front driveshafts driven by the two-speed final drive assembly;a pair of rear driveshafts;a rear differential assembly connected to the two-speed final drive assembly and including, a high capacity mode and a low capacity mode,an input member driven by the two-speed final drive assembly,first and second clutch assemblies selectively coupling the input member to a respective one of the pair of rear driveshafts, each of the clutch assemblies including, a plurality of driven plates connected to the input member, anda plurality of driving plates selectively engageable with the plurality of driven plates,first and second pistons each associated with a respective one of the first and second clutch assemblies, each of the first and second pistons configured to displace the plurality of driving plates into engagement with the plurality of driven plates,a variable displacement pump, anda purge valve, wherein the purge valve and at least one of the first and second pistons are in parallel fluid communication with the variable displacement pump; anda control assembly including, a controller in electrical communication with the variable displacement pump and the purge valve, andan input array in electrical communication with the controller and including, a plurality of sensors, andat least one switch accessible to an operator of the vehicle. 2. The drivetrain of claim 1, wherein the controller is configured to: select one of the low range final drive ratio and the high range drive ratio based on electrical communication from the input array;operate the two-speed final drive assembly in the selected one of the low range drive ratio and the high range drive ratio;select one of the high capacity mode and the low capacity mode based on electrical communication from the input array; andcause the rear differential assembly to operate in the selected one of the high capacity mode and the low capacity mode. 3. The drivetrain of claim 2, wherein each of the high capacity mode and the low capacity mode includes a full capacity mode. 4. The drivetrain of claim 3, wherein the controller is configured to select the high capacity mode when the two-speed final drive assembly is in the low range final drive ratio. 5. The drivetrain of claim 1, wherein the control assembly includes an actuator connected to the two-speed final drive assembly and configured to selectively engage one of the low range final drive ratio and the high range final drive ratio. 6. The drivetrain of claim 5, wherein the controller includes, a first control unit in electrical communication with each of the multi-ratio transmission and the actuator, anda second control unit in electrical communication with each of the first control unit, the variable displacement pump, and the purge valve. 7. The drivetrain of claim 1, wherein the input array includes at least one of, a vehicle dynamics array configured to collect data indicative of at least one dynamic condition of the vehicle,a vehicle load detection array configured to collect data indicative of a cargo load applied to the vehicle,a manual override array configured to detect manual input by an operator of the vehicle, anda trailer detection array configured to collect data indicative of a trailer coupled to the vehicle. 8. The drivetrain of claim 1, wherein the input array includes at least one of, mass airflow sensor in electrical communication with the controller,a longitudinal acceleration sensor in electrical communication with the controller,a vehicle speed sensor in electrical communication with the controller,an accelerator pedal position sensor in electrical communication with the controller, anda gear shift lever position sensor in electrical communication with the controller. 9. The drivetrain of claim 1, wherein the input array includes at least one of: a suspension load sensor; anda cargo load sensor. 10. The drivetrain of claim 1, wherein the input array is configured to calculate an acceleration-based load. 11. The drivetrain of claim 1, wherein the input array includes at least one of: a low range switch configured to signal the controller to select the low range final drive ratio,a tow/haul switch configured to signal the controller to select the high capacity mode, anda rear differential lock switch configured to signal the controller to select the full capacity mode of a selected one of the high capacity mode and the low capacity mode. 12. The drivetrain of claim 1, wherein the input array includes at least one of a rear facing camera in electrical communication with the controller;a drawbar load sensor in electrical communication with the controller; anda trailer electrical harness sensor in electrical communication with the controller. 13. A method for controlling the drivetrain according to claim 1 comprising: collecting data indicative of at least one of a dynamic condition of the vehicle and a static condition of the vehicle; andoperating the rear differential assembly in one of the low capacity mode and the high capacity mode based on the data. 14. The method of claim 13, further comprising: providing a rear differential lock button having an ON position and an OFF position;providing the rear differential assembly with a full mode for each of the high capacity mode and the low capacity mode;checking whether the rear differential lock button is in the ON position or the OFF position; andoperating the rear differential assembly in the full mode of either of the high capacity mode and the low capacity mode when the rear differential lock button is in the ON position. 15. The method of claim 13, further comprising: providing a low range button having an ON position and an OFF position;checking whether the low range button is in the ON position or the OFF position;operating the two-speed final drive assembly at the low range final drive ratio when the low range button is in the ON position; andoperating the rear differential assembly in the high capacity mode when the low range button is in the ON position. 16. A drivetrain for a vehicle comprising: a multi-ratio transmission;a final drive assembly connected in series with the multi-ratio transmission and including a low speed final drive ratio and a high speed final drive ratio;a pair of front driveshafts driven by the final drive assembly;a pair of rear driveshafts;a rear differential assembly selectively connected to the final drive assembly and including: a high capacity mode and a low capacity mode;an input member driven by the final drive assembly;at least one clutch assembly selectively coupling the input member to at least one of the pair of rear driveshafts, the at least one clutch assembly including: at least one driven plate connected to the input member; andat least one driving plate selectively engageable with the plurality of driven plates; andan actuator assembly configured to displace the at least one driven plate into engagement with the at least one driving plate; anda controller in electrical communication with the final drive assembly and the actuator assembly, and the controller being configured to: select one of a low range mode and a high range mode;signal the final drive assembly to engage the low speed final drive ratio when the controller selects the low range mode and to engage the high speed final drive ratio when the controller selects the high range mode;select one of the high capacity mode, the low capacity mode, and a front-wheel drive (FWD) mode; andsignal the actuator assembly to engage the at least one driven clutch with the at least one driving plate when the high capacity mode or the low capacity mode is selected. 17. The drivetrain of claim 16, wherein the controller is configured to: receive data indicative of at least one of a dynamic condition of the vehicle and a static condition of the vehicle; andselect the one of the low capacity mode and the high capacity mode based on the received data. 18. The drivetrain of claim 17, wherein the at least one dynamic condition of the vehicle includes at least one of mass airflow, longitudinal acceleration, vehicle speed, pedal position, gear selector position, and a road grade. 19. The drivetrain of claim 17, wherein the at least one static condition of the vehicle includes at least one of a suspension load, a cargo load, a rear view camera image, a connection with a trailer wire harness, a drawbar load applied to the vehicle, and an acceleration-based load. 20. The drivetrain of claim 16, wherein: the rear differential assembly further includes a full capacity mode for each of the high capacity mode and the low capacity mode such that a respective maximum torque of the selected one of the high capacity mode and the low capacity mode is transmitted through the rear differential;the actuator assembly further includes a rear differential lock switch having an ON position and an OFF position, a low range switch having an ON position and an OFF position, a tow/haul switch having an ON position and an OFF position, and an all-wheel drive (AWD) switch having an ON position and an OFF position; andthe controller being in electrical communication with the rear differential lock switch, the low range switch, the tow/haul switch, and the AWD switch, and the controller being configured to: select the full capacity mode of the selected one of the high capacity mode and the low capacity mode when the rear differential lock switch is in the ON position;select the low range mode when the low range switch is in the ON position;select the high capacity mode when the tow/haul switch is in the ON position;select the high capacity mode when the tow/haul switch is in the ON position; andselect the high capacity mode or the low capacity mode when the AWD switch is in the ON position. 21. The drivetrain of claim 16, wherein the actuator assembly includes: an on-demand variable displacement pump having a low displacement setting and a high displacement setting;a purge valve in fluid communication with the on-demand variable displacement pump; anda piston in fluid communication with the on-demand variable displacement pump in parallel with the purge valve, the piston being movable in response to the fluid communication to cause displacement of the at least one driven plate into engagement with the at least one driving plate and the piston applying an engagement force when the at least one driven plate engages the at least one driving plate, andthe controller being configured to: select the low displacement setting when the high capacity mode is selected and select the high displacement setting when the low capacity mode is selected;select a position of the purge valve based on at least one condition of the vehicle;signal the variable displacement pump to operate at the selected one of the low displacement setting and the high displacement setting; andsignal the purge valve to move to the selected position. 22. The drivetrain of claim 16, wherein the final drive assembly further includes an input gear, an output gear, and a second clutch assembly selectively connecting the output gear to the input gear,the at least one driven plate being connected to one of the pair of rear driveshafts,the clutch assembly further including at least one second driven plate connected to the input member and at least one second driving plate selectively engageable with the at least one second driven plate and connected to another one of the pair of rear driveshafts,the actuator assembly configured to displace the at least one second driven plate into engagement with the at least one second driving plate, andthe controller being in electrical communication with the second clutch assembly and configured to: select one of the FWD mode and an all-wheel drive (AWD) mode;signal the second clutch to disconnect the input gear from the output gear when the FWD mode is selected;signal the second clutch to connect the input gear to the output gear when the AWD mode is selected;select the high range mode when the FWD mode is selected,select the low range mode or the high range mode when the AWD mode is selected;signal the actuator assembly to modulate an engagement force applied by the at least one driven plate and the at least one second driven plate with the respective at least one driving plate and at least one second driving plate when the AWD mode is selected. 23. The drivetrain of claim 16, further comprising a plurality of sensors in electrical communication with the controller, each sensor being configured to detect a respective condition of the vehicle and to transmit a signal to the controller indicative of the respective condition, and wherein the controller is configured to: select one of the low range mode and the high range mode based on the signal from at least one of the plurality of sensors, andsignal the actuator to displace the at least one driven plate and to apply an engagement force to the driven plate based on the signal from at least one of the plurality of sensors. 24. The drivetrain of claim 16, wherein the controller is configured to: receive data indicative of a mass airflow rate and of an accelerator pedal position;calculate a torque value based on the mass airflow data;compare the torque value to a torque threshold;compare the accelerator pedal position data to a pedal threshold; andselect the high capacity mode when the torque value is greater than the torque threshold or when the accelerator pedal position data is greater than the pedal threshold. 25. The drivetrain of claim 16, wherein the controller is configured to: receive data indicative of at least one of a throttle angle and vehicle acceleration;select a road grade value based on the throttle angle data, the sensed vehicle acceleration data, a predetermined throttle angle, and a predetermined acceleration;compare the road grade value to a road grade threshold; andselect the high capacity mode when the road grade value is greater than the road grade threshold. 26. The drivetrain of claim 16, wherein the controller is configured to: receive data indicative of an actual acceleration of the vehicle;calculate an acceleration-based load based on the actual acceleration and a theoretical acceleration; andselect one of the high capacity mode and the low capacity mode based on the acceleration-based load. 27. The drivetrain of claim 16, wherein a maximum torque transmitted through the rear differential to the rear driveshafts when the rear differential is in the high capacity mode is greater than a maximum torque transmitted through the rear differential assembly when the rear differential assembly is in the low capacity mode. 28. The drivetrain of claim 16, wherein the controller is further configured to: select one of a plurality of actuator forces based on at least one of a plurality of dynamic conditions and static conditions of the vehicle;signal the actuator assembly to displace the at least one driven plate into engagement with the at least one driving plate when the high capacity mode or the low capacity mode is selected; andsignal the actuator assembly to apply the selected one of the actuator forces to the at least one driven plate when the at least one driven plate is in engagement with the at least one driving plate.