With planetary gears, even without a control device, the component can act as a(n) ________ if it requires a load to turn.

With planetary gears, even without a control device, the component can act as a(n) ________ if it requires a load to turn.

• A. Servo piston
• B. Idler gear
• C. Held member
• D. Epicyclical gear

Answer: (C)

In a planetary gear set, one member can become the held member simply due to how the load reacts within the gear train, even if there’s no brake or clutch engaged. When torque is applied and a load is connected to turn, the resistance from that load forces a reaction through the gears. That reaction can prevent a particular component from rotating, effectively holding it in place while the other parts of the set continue to move around it. This held state is not caused by a separate control device; it arises from the load’s demand and the way the force couples through sun, planet, carrier, and ring gears. The term describes the component that remains stationary under operation because the load is enforcing that restraint.