Transfer for a four-wheel drive vehicle

In a power transfer arrangement for a four-wheel drive vehicle, the power transfer arrangement being connected to and driven by a transmission associated with a vehicle engine, said transfer arrangement comprising:

• an input shaft to which rotational torque is transmitted from the engine through the change speed transmission;
• a center differential aligned with the input shaft to distribute drive torque to front and rear wheels of the vehicle;
• a high/low speed transmission connected between the input shaft and the center differential for converting the rotation of the input shaft into high and low speeds which are transmitted to the center differential;
• said high/low speed transmission including a first gear attached to said input shaft for rotation therewith, a first counter gear attached to a counter shaft in parallel with said input shaft and in meshing engagement with said first gear to receive the rotation thereof, a second counter gear attached to said counter shaft and rotating therewith, and a second gear aligned with said input shaft and rotatably supported therealong and maintained in meshing engagement with said second counter gear to receive the rotation thereof, and high speed-side and low speed-side output parts respectively attached to said first and second gears;
• said center differential including a center differential housing mounting thereon at least one differential pinion gear, said center differential housing being supported for rotation in alignment with said input shaft and disposed axially between said high speed-side and low speed-side parts;
• said center differential including first and second differential side gears disposed on opposite axial sides of said differential housing and disposed in meshing engagement with the differential pinion gear, said first differential side gear being disposed between said differential housing and said input shaft and being generally surrounded by said first gear;
• said second differential side gear being disposed on an opposite axial side of said differential housing drivingly connected to a first output shaft which is coaxially aligned with the input shaft and is drivingly connectable for driving rear wheels of the vehicle and generally surrounded by said second gear, said second differential side gear being fixed to a second output shaft which concentrically and rotatably surrounds said first output shaft and is adapted for driving connection to front wheels of the vehicle;
• and
• a shiftable engaging device disposed adjacent said center differential generally axially between said high speed-side and low speed-side output parts and shiftable axially therebetween for drivingly engaging said high speed-side output part or said low speed-side output part for respectively defining high and low speeds, said shiftable engaging device being drivingly coupled to said differential housing.