The cardan shafts are the most important components of
the traction and transmission system, in order to prevent the
possibility of the cardan shafts' becoming flexible caused by
losing balance. Shaft deceleration gear case is connected
with bogie frame through an elastic suspension device,
where sensors used for monitoring crack and losing balance
should be installed. If the cardan shaft overbalances, the
sensor will send out the signal to cause the brake promptly
and cut off the power at the same time. The driver will drive
the train at low speed to parking.