Differential gear, in auto mechanics, gear arrangement that allows power from the engine to be transmitted to a pair of traveling wheels, dividing the force equally between them but permitting them to follow paths of different lengths, as when turning a corner or traversing an uneven street. On a straight street the tires rotate at the same swiftness; when turning a part the outside wheel offers farther to move and can turn faster than the inner steering wheel if unrestrained.
The components of the coupling China Ever-Power differential are demonstrated in the Figure. The power from the transmitting is delivered to the bevel ring equipment by the drive-shaft pinion, both of which are held in bearings in the rear-axle casing. The case is an open boxlike structure that’s bolted to the band gear and contains bearings to support a couple of pairs of diametrically opposite differential bevel pinions. Each wheel axle is mounted on a differential side equipment, which meshes with the differential pinions. On a straight road the tires and the medial side gears rotate at the same acceleration, there is absolutely no relative motion between the differential aspect gears and pinions, and they all rotate as a device with the case and ring gear. If the automobile turns to the left, the right-hand steering wheel will be required to rotate faster compared to the left-hand steering wheel, and the medial side gears and the pinions will rotate relative to one another. The ring equipment rotates at a swiftness that is add up to the mean speed of the remaining and right wheels. If the tires are jacked up with the transmitting in neutral and among the tires is turned, the opposite wheel will turn in the opposite direction at the same swiftness.
The torque (turning instant) transmitted to the two wheels with the 
Ever-Power differential may be the same. Therefore, if one wheel slips, as in ice or mud, the torque to the other steering wheel is decreased. This disadvantage could be overcome somewhat by the usage of a limited-slip differential. In one version a clutch connects among the axles and the band gear. When one steering wheel encounters low traction, its inclination to spin is resisted by the clutch, thus providing higher torque for the other wheel.
OPEN DIFFERENTIAL:
A differential in its most basic form comprises two halves of an axle with a equipment on each end, connected together by a third gear creating three sides of a sq .. This is generally supplemented by a 4th gear for added power, completing the square.