0 a device fitted to the axle of a vehicle that allows the wheels to turn at different rates when going around a corner -- 差速齿轮
The differential gears could have been used to keep a mechanically-operated pointer aiming in a fixed direction, to the south, compensating for whatever turns the chariot made.
Differential gears in the center worked as a reverse gear and the two speed had a centrifugal gear change.
The rear differential gear ratio was changed to 3.31:1 for both transmissions.
The differential gears are commonly applied in automotive systems to split the input engine torque two ways, allowing each output to spin at different speeds.
Lacking this extra gear meant that reverse was done with a differential gear.
It requires a differential gear, a gearing arrangement that sums or differences two angular inputs.
The differential gears are part of the input drive shaft rather than between the output axles as in a conventional differential.
The addition is done by an analogue method, using a differential gear.