These are electric vehicles that have an extended range due to their different series and/or hybrid layouts. The primarily electric vehicle also has a smaller ICE onboard that switches on once the battery that powers the electrci motor is empty.
The Rear Drive Module is a compact, light weight gear box with disconnect clutch for electric motor assisted AWD solutions. The simple interface allows the gear box to be combined with various E-motors technologies. The controlled disconnect clutch allows seamless switching from 4WD to 2WD mode. The gearbox is used in on-demand rear axles driven by an electric motor. The E-motor torque is geared up to axle torque by a two stage reduction gear. When the E-motor is reaching its speed limit or the driver is selecting the 2WD mode, the controlled clutch disconnects the motor from the differential. The low drag torque of the disconnect clutch provides superior fuel efficiency of the E-AWD in 2WD mode.
The majority of rear-wheel drive vehicles have engines mounted at the front. Power produced by the engine is transferred to the rear wheels via the longitudinal propshaft, the differential and the two sideshafts. This system is more complicated than that for front-wheel drive and is widely used in high performance and luxury class cars.
Also known as rotational backlash, this is the amount of angular clearance which can be detected or measured within a geared system. Generally, the lower the backlash, the better for noise, NVH, etc, although a certain amount may be required to compensate for tooth error without gear jamming.
A rubber coupling is suitable when very low running angles (<1°) are required and a level of torsional compliance is required in the driveline system.
The fixed ball joint is fitted to the outboard area of a sideshaft enabling the shaft to articulate with the wheel suspension movement. This joint was developed according to the principle that the balls should always assume a position corresponding to the bisected articulation angle between the axes of the driving and driven shafts. The joint takes on the function of two bevel gears but has the important advantage of enabling continuous change of articulation angle. The centre points of the tracks are offset from the centre-point of the joint. At all times these crossing ball tracks maintain the balls in position at the half-angle (the bisecting plane). The torque is normally transferred by six balls. To improve the track control of the balls a cage is positioned between the outer and inner races. The cage holds the balls on the outer joint housing, preventing them from dropping out. This design was originally patented by Alfred Hans Rzeppa in 1929, with the offset control feature further developed by Bernard Stuber in 1933. In 1959, the Mini was the first car to use a ball-type constant velocity joint, whilst the Rzeppa style joint was fitted to the DKW Junior F11.