Why is there no torque along this axis?

[Kashmir]

Kleppner and Kolenkow say "Consider a gyrocompass consisting of a balanced spinning disk a light frame supported by a horizontal axle. The assembly is turntable rotating at steady angular velocity Ω. There cannot be any torque along the horizontal AB axis because the axle is pivoted".

I'm not getting why there can be no torque along the axle due to it being pivoted ?

 

[anuttarasammyak]

Because the axis is pivoted with no torque transmitted from Y shape pillars to the gyro, I assume.

 

[Lnewqban]

Pivots are unable to transfer moments or torques.
The spinning disc could apply a huge torque on the rotating plane to the horizontal axis AB, but none of it could ever reach the turnable disc.
It is exactly what happens between the spinning shaft of an electric motor and its anchored base.