Red Seal Industrial Mechanic (Millwright) Practice Exam

What is the primary function of a gearbox?

1. To increase speed and decrease torque of the input shaft.

2. To reduce speed and increase torque of the input shaft.

3. To maintain constant speed of the output shaft.

4. To convert rotational motion into linear motion.

The correct answer is: To reduce speed and increase torque of the input shaft.

The primary function of a gearbox is to reduce speed and increase torque of the input shaft. Gearboxes achieve this through the use of different gear ratios, which allow for a transformation of the input power into a more useful output for specific applications. When a gearbox is used, the rotational speed provided by the motor or input shaft is decreased, but the amount of torque is increased proportionally. This is particularly important in applications where high torque is needed to perform work, such as in heavy machinery or automotive applications where the power must be transmitted to the wheels. The mechanical advantage gained through the gearbox allows for effective control of speed and force, enabling machinery to operate optimally under various load conditions. Understanding this principle is vital for millwrights as they work with machinery and have to select or design gear systems that meet the operational requirements of different tasks.