Loads on rear axle shafts
Shearing force due to wt. of vehicle .
Bending moment on account of load applied through
spring seats .
End thrust caused by side forces on account of
cornering , side wind
Bending moment by end thrust and its reation offered
by tyres on ground
Driving torque
Types of rear axle shaft
Semi floating axle .
Full floating axle .
Three quarter floating type.
SEMI FLOATING AXLE
With a semi-float axle, the axle shaft both carries the
weight and transmits torque.
The wheel is often bolted directly to the flange on the
axle.
Semi-float axles are seen on cars and light duty trucks.
Semi floats are more limited in capacity, but lighter
and cheaper to manufacture.
FULL FLOATING AXLE
the weight of the vehicle is supported by the axle
housing- more specifically, a bearing spindle attached
to the axle housing , and a set of bearings in a separate
wheel hub.
Torque is transmitted by a separate axle shaft that
carries no weight.
As commonly built, full-floaters are considerably
heavier, but also much stronger
SEMI FLOATING AXLE FULL FLOATING AXLE
THREE QUARTER FLOATING
TYPE
THREE QUARTER FLOATING
TYPE
A three-quarter floating axle is the same as semi-floating, with
one difference. The outer bearing is moved to the outside of the
outer end of the axle tube, supporting a hub assembly via the
bearing's outer circumference edge.
The splined or keyed shaft drives this hub, to which the wheel is
attached.
The shaft now supports minimal vehicle weight (so has much
reduced radial load), but still locates the wheel axially, and
transfers axial cornering loads (side thrust) to the axle inner
bearing.
