Abstract: A method and apparatus for operating a power transfer device such as a vehicle transfer case having, shaft speed sensors, a two speed (high-low) drive assembly, an electrically, pneumatically or hydraulically operated shift operator and a microprocessor comprising the steps of sensing the speeds of the transfer case input shaft and output shaft, calculating the rate of change (.DELTA.S/.DELTA.t) of the speed of the input shaft, predicting, based upon such rate of change, a time when the input shaft and the output shaft will be synchronized and commencing movement of such shift operator at a time prior to such synchronization in order to effect engagement of such clutch into high gear at substantially the instant of synchronization.

Abstract: The two-speed compounder of the present invention is adapted to be mounted to an existing transmission and includes an input adapted to be driven by the transmission output shaft, an output adapted to be connected to the vehicle's driveline, a planetary gearset operably interconnecting the input to the output, and a power transfer mechanism for selectively transferring power from the input through the planetary gearset to the output at either of the direct speed ratio or the reduced speed ratio. The planetary gearset has a first gear component driven by the input, a second gear component, and a third gear component rotatably interconnecting the first and second gear components and driving the output. When it is desired to establish the direct drive speed ratio, the first and third gear components of planetary gearset are coupled together for preventing relative rotation therebetween.

Abstract: The present invention is directed to a two-speed gear reduction unit and a shift mechanism for establishing two distinct speed ratio drive connections between an input member and an output member. More specifically, the shift mechanism includes a clutch apparatus for stopping relative rotation between the input and output members prior to shifting the gear reduction unit from its neutral operating state into either of its high-range or low-range operating states. Thus, the present invention is adapted for use in the transfer case of a four-wheel drive vehicle for shifting between four-wheel high-range and low-range drive modes.

Abstract: A sub-transmission of a transfer unit includes a shift sleeve that moves to a neutral position N where it does not engage with a high-speed gear set to an input shaft or a low-speed gear set to a deceleration system, and thereafter engages with the high- or low-speed gear to transfer the driving force of the input shaft to an output shaft in the form of a high-speed or low-speed driving force. The output shaft has an outer periphery provided with an annular friction member in contact with the input shaft, for reducing the rotational speed of the input shaft, and thereby decreasing gear screeches during a changeover between low- and high-speed positions, even if a free-running torque is transferred to the input shaft from a hydrodynamic automatic transmission.

Abstract: An automatic four-wheel-drive vehicle having a multiple-ratio transmission with a torque output shaft connected drivably to a rear driving axle and a transfer gear box having a front drive shaft connected drivably to a front axle, the transfer case providing a four-wheel low-drive mode, a neutral mode and a two-wheel-drive/automatic four-wheel drive mode, an electric motor adapted to shift the transfer case from one mode to another mode and an electronic controller responsive to predetermined driving conditions for effecting an automatic shift of the transfer case from either a forward drive mode or a reverse drive mode to the neutral drive mode whereby the vehicle is conditioned for towing by interrupting the torque flow path from the rear drive wheels of the vehicle to the transmission mechanism and transfer case.

Abstract: A transfer case for a part-time four wheel drive vehicle includes a planetary gear speed reduction assembly driven by the transfer case input shaft for providing high and low speed range outputs. The planetary gear assembly is disposed between and is selectively engaged by primary and secondary clutch collars, the primary clutch driving the rear (primary) output shaft in either the high or low speed ranges. The secondary clutch drives the front (secondary) output shaft through a chain drive in the low range. The clutch collars are controlled by a single (common) clutch operator. An electromagnetic clutch assembly driven by the input shaft selectively drives the front output shaft chain drive. The electromagnetic clutch functions both as a synchronizer and torque delivery device. The transfer case may be combined with a control which facilitates direct selection of vehicle drive mode.

Abstract: A combined powershift transmission and main clutch assembly for a vehicle includes a casing containing an input shaft and an output shaft. A planetary transmission is disposed within the casing and is co-axially mounted around the input shaft. The planetary powershift unit includes a sun gear and an annulus gear interconnected by one or more planet gears carded on a planet carder. A first one of the sun gear, the annulus gear, and the planet carder is connected to the input shaft, while a second one of the sun gear, the annulus gear, and the planet carder acts as an output member of the planetary powershift unit. A first clutch is disposed within the casing and co-axially surrounds the output shaft for drivingly connecting the output member of the planetary powershift unit with the output shaft.

Abstract: A transfer case for a part-time four wheel drive vehicle includes a planetary gear speed reduction assembly driven by the transfer case input shaft for providing high and low speed range outputs. The planetary gear assembly is disposed between and is selectively engaged by primary and secondary clutch collars, the primary clutch driving the rear (primary) output shaft in either the high or low speed ranges. The secondary clutch drives the front (secondary) output shaft through a chain drive in the low range. The clutch collars are controlled by a single (common) clutch operator. An electromagnetic clutch assembly driven by the input shaft selectively drives the front output shaft chain drive. The electromagnetic clutch functions both as a synchronizer and torque delivery device. The transfer case may be combined with a control which facilitates direct selection of vehicle drive mode.

Abstract: The present invention relates to a vehicle four wheel drive torque transfer case having a friction clutch which is selectively engaged when it is desired to place the transfer case in a four wheel drive operating mode. The transfer case includes an input shaft which is connected to supply torque to a rear output shaft. A multi-disc friction clutch is connected between the input shaft and a front output shaft for supplying torque to the front output shaft. A planetary gear assembly includes a sun gear, a carrier a planet carrier connected to the input shaft, and a ring gear coupled to drive the front output shaft. The multi-disc clutch is interposed between the sun gear and the ring gear and is engaged to inhibit any rotation of the planet carrier relative to the ring gear and thereby transfer torque to the front output shaft. The planetary gear assembly functions as a .sctn.'torque multipler" and this reduces the torque capacity requirements for the clutch.

Abstract: A transfer device is provided for distributing the output of a transmission to front wheels and rear wheels of the vehicle through a front power train and a rear power train. The output shaft of the transmission is operatively connected to the rear power train. The transfer device has a drive gear rotatably mounted on an output shaft of the transmission and engaged with a driven gear in the front power train, a fluid operated multiple-disk friction clutch having a drive drum and a driven drum. The driven drum is secured to the drive gear and the drive drum is secured to the output shaft. The output shaft of the transmission and the drive gear are arranged to be changed with an output shaft and a drive gear for the front power train which are engaged with each other, and an input member of the rear power train is arranged to be secured to the drive drum.

Abstract: The invention relates to a gearbox arrangement for driving a first multi-bladed rotor and a second coaxial multi-bladed rotor in opposite directions.The gearbox assembly comprises a first epicyclic gear arrangement and a coaxial second epicyclic gear arrangement. The first epicyclic gear arrangement is driven by a first input shaft, and the second epicyclic gear has a static second input shaft. The first epicyclic gear arrangement is drivingly connected to the first multi-bladed rotor and the second epicyclic gear arrangement is drivingly connected to the second multi-bladed rotor. The first epicyclic gear arrangement is interconnected to the second epicyclic gear arrangement so that the first and second multi-bladed rotors are driven in opposite directions.