What mechanical device is used in larger synchro units to provide a retarding action on the rotor?

In larger synchro units, an inertia damper is employed to provide a retarding action on the rotor. The primary function of the inertia damper is to absorb and dissipate fluctuations in motion, which helps to stabilize the rotor's speed and position during operation. This is especially important in synchro systems where precision and smooth operation are required.

Inertia dampers typically consist of a mass that is connected to the rotor in such a way that it can move independently to counteract rapid changes in speed. When the rotor experiences sudden changes in direction or velocity, the inertia damper’s mass will react to those changes, providing damping effects that reduce oscillations and improve overall system stability.

This is particularly crucial in applications that involve feedback control and precision positioning, where any unwanted movement can result in inaccuracies in the system's performance. Other devices, such as gearboxes, flywheels, and clutches, may serve different functions related to power transmission, torque multiplication, or engagement and disengagement of motion, but they do not specifically provide the retarding action on the rotor that the inertia damper does. Thus, the use of an inertia damper is key in ensuring that larger synchro units operate effectively and reliably.