Page 162 - Tribology in Machine Design
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148 Tribology in machine design
Equation (4.151) neglects the inertia couples due to the wheels. For greater
accuracy we write
From eqns (4.150) and (4.151)
Thus forward acceleration increases the load on the rear wheels and
diminishes the load on the front wheels of the car. Again, since FI =fR\., eqn
(4.153) gives
where
Writing (F l-F 2) = Mv and W=Mg, then from eqn (4.155)
Case B. Braking conditions
Brakes applied to both rear and front wheels
Proceeding as in the previous paragraph, let L^ and L 2 represent the
braking torques applied to the rear and front axles; F t and F 2 denote the
tangential resistance to skidding. Referring to Fig. 4.47, v is the maximum
possible retardation and a the corresponding angular retardation of the
wheels, so that, if skidding does not occur, we have:
from which
where
Figure 4.47
