  We investigate a problem about the competition between the hybridization and
the Hund-rule coupling by applying the Wilson numerical renormalization-group
method to the extended Kondo model where the impurity spin interacts via the
Hund-rule coupling, with an extra spin which is isolated from the conduction
electrons. It is shown that the Hund-rule coupling is an irrelevant
perturbation against the strong coupling fixed point. However, the Hund-rule
coupling decreases the characteristic energy $T_K$ drastically to the lower
side and the irrelevant operator, which describes the low energy physics, takes
a form of ferromagnetic exchange interaction between the extra spin and the
Kondo resonance states because of the existence of the Hund-rule coupling.
