What is the purpose of a torque limiter on a drive shaft?

• A. To increase torque during overload.
• B. To protect equipment by slipping or reducing torque when overload occurs.
• C. To measure torque for display.
• D. To heat the system.

Answer: (B)

The main idea is protecting the drive system by preventing overload damage. A torque limiter is built to slip or reduce the transmitted torque when the load on the shaft becomes excessive. By letting the driving and driven parts slip or disengage at a preset torque, it keeps gears, bearings, and couplings from being overstressed, which could cause gear teeth to break or shafts to shear. This protective action is what makes it effective: it doesn’t aim to increase torque during overload, nor does it function as a torque display sensor. Heat generation can occur when slipping happens, but that isn’t the purpose of the device.