Mechanical systems 2
|The ruf has two electric motors placed
inside the drive wheels. The motors rotate independently so a differential is not needed.
The two motor systems can be moved such that there is space for the rail when it enters
the rail. Once on the rail the drive wheels close around the rail and the pressure is
adjusted to obtain the needed friction. This means that friction normally is low and only
during slopes or speed change the friction is increased.
The wheels which carry the ruf on the rail have low friction. This is possible because they are not used for braking.
Normal braking is obtained by using the motors to brake the ruf and return power to the ruf power system (the rail). There is no transmission losses between the rail and the motors, so efficiency is very high.
Modern electric motors have a very high efficiency and can be controlled very precisely.