Abstract: A torque transfer system for transferring torque between a first rotary member and a second rotary member includes a clutch pack that is operably disposed between the first rotary member and the second rotary member to regulate torque transfer therebetween and a clutch actuator for regulating engagement of the clutch pack. A controller generates a dithered control signal by superimposing a dithering signal onto a digital control signal. The controller determines a time averaged duty cycle DCavg of the dithered control signal, determines an amplitude AMP of the dithered control signal, determines a wave function WF that describes a wave shape of the dithered control signal and calculates a pulse duty cycle PDC for each pulse of the dithered control signal using the average duty cycle, amplitude, and wave function.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A method for operating a transfer case synchronized range shift mechanism. The range shift mechanism can be selectively actuated for establishing a four-wheel high-range drive mode, a neutral mode, and a four-wheel low-range drive mode. The synchronized range shift mechanism is comprised of a first input gear system, a second input gear system, and an output gear system. The output gear system is comprised of a rotary output member that may be selectively engaged with either the first input gear system or the second input gear system, depending on which four-wheel-drive operating mode the vehicle operator selects. The range shift mechanism is further comprised of a synchronizing mechanism. The method for controlling the speed of the range shift as a means for reducing the time it takes to perform the range shift.

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: A torque transfer mechanism for controlling the magnitude of a clutch engagement force exerted on a clutch pack that is operably disposed between a first rotary member and a second rotary member includes a hydraulic clutch actuation system. The hydraulic clutch actuation system includes an electric motor drivingly coupled to a pump. The pump supplies pressurized fluid to an accumulator. The pressurized fluid within the accumulator is selectively supplied to a piston to provide a clutch engagement force.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor requirements.

Abstract: In accordance with the present invention, a preferred method is disclosed for operating a transfer case synchronized range shift mechanism. The range shift mechanism can be selectively actuated for establishing a four-wheel high-range drive mode, a neutral mode, and a four-wheel low-range drive mode. The synchronized range shift mechanism is comprised of a first input gear system, a second input gear system, and an output gear system. The output gear system is comprised of a rotary output member that may be selectively engaged with either the first input gear system or the second input gear system, depending on which four-wheel-drive operating mode the vehicle operator selects. The range shift mechanism is further comprised of a synchronizing mechanism. The present invention discloses a novel method for controlling the speed of the range shift as a means for reducing the time it takes to perform the range shift.

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: In accordance with the present invention, a preferred method is disclosed for operating a transfer case synchronized range shift mechanism. The range shift mechanism can be selectively actuated for establishing a four-wheel high-range drive mode, a neutral mode, and a four-wheel low-range drive mode. The synchronized range shift mechanism is comprised of a first input gear system, a second input gear system, and an output gear system. The output gear system is comprised of a rotary output member that may be selectively engaged with either the first input gear system or the second input gear system, depending on which four-wheel-drive operating mode the vehicle operator selects. The range shift mechanism is further comprised of a synchronizing mechanism. The present invention discloses a novel method for controlling the speed of the range shift as a means for reducing the time it takes to perform the range shift.

Abstract: The present invention discloses a preferred method for operating a adaptive clutch system of the type used in a motor vehicle power transfer assembly by employing a dithered control signal. One aspect of the present invention superimposes a dithering signal onto a control signal by nulling consecutive blocks of control signal pulses. Another aspect of the present invention provides a method for generating a dithered control signal by providing a wave function with which to systematically vary a duty cycle of the dithered control signal. A method for varying the output force of a clutch actuator assembly in response to the dithered control signal is also provided.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A two-speed full-time transfer case includes an input shaft, first and second output shafts, a planetary gearset, an interaxle differential, and first and second clutch mechanisms. The planetary gearset includes a sun gear integral with the input shaft, an annulus gear, and pinion gears rotatably mounted on a carrier and which are meshed with the sun and annulus gears. The interaxle differential has an input driven by the carrier, a first output driving the first output shaft and a second output driving a transfer mechanism coupled to the second output shaft. The first clutch mechanism is a fluid-actuated bi-directional overrunning clutch operable for selectively braking the annulus gear. The second clutch mechanism is a fluid-released bi-directional overrunning clutch for selectively releasing the input shaft from coupled engagement with the carrier.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: A power transfer system is provided and equipped with a torque transfer coupling which includes a clutch and a ball-screw actuator. The ball-screw actuator functions to axially translate an apply plate via a closed hydraulic system to operatively engage the clutch and vary the frictional engagement thereof.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor requirements.

Abstract: The present invention is directed to a power transfer system for a four-wheel drive vehicle equipped with a torque transfer coupling which includes a clutch pack and a ball-screw actuator. The ball-screw actuator functions to axially translates an apply plate to operatively engage the clutch pack and vary the frictional engagement. This arrangement yields numerous operational advantages over the prior art including, but not limited to, establishing a direct drive between the motor output shaft and the apply plate, concentric mounting of the actuator elements with the motor output shaft, and a simplified mechanical arrangement that reduces the number of frictional elements increasing operational efficiency and decreasing motor requirements.

Abstract: In accordance with the present invention, a preferred method is disclosed for operating a transfer case synchronized range shift mechanism. The range shift mechanism can be selectively actuated for establishing a four-wheel high-range drive mode, a neutral mode, and a four-wheel low-range drive mode. The synchronized range shift mechanism is comprised of a first input gear system, a second input gear system, and an output gear system. The output gear system is comprised of a rotary output member that may be selectively engaged with either the first input gear system or the second input gear system, depending on which four-wheel-drive operating mode the vehicle operator selects. The range shift mechanism is further comprised of a synchronizing mechanism. The present invention discloses a novel method for controlling the speed of the range shift as a means for reducing the time it takes to perform the range shift.

Abstract: A two-speed full-time transfer case includes an input shaft, first and second output shafts, a planetary gearset, an interaxle differential, and first and second clutch mechanisms. The planetary gearset includes a sun gear integral with the input shaft, an annulus gear, and pinion gears rotatably mounted on a carrier and which are meshed with the sun and annulus gears. The interaxle differential has an input driven by the carrier, a first output driving the first output shaft and a second output driving a transfer mechanism coupled to the second output shaft. The first clutch mechanism is a fluid-actuated bi-directional overrunning clutch operable for selectively braking the annulus gear. The second clutch mechanism is a fluid-released bi-directional overrunning clutch for selectively releasing the input shaft from coupled engagement with the carrier.