How gears, pulleys and winding drums lift a load

A lifting machine is a system. The handle, gears, winding drum, cable, pulleys and load all affect one another. Understanding the machine means following the force and motion from the person turning the crank to the cage moving in the shaft.

Start at the crank

Turning the crank applies a force at a distance from the centre of rotation. That creates torque: the turning effect of a force. A longer crank can make it easier to turn the shaft, although the hand must travel through a larger circle.

What the gears change

Meshing gears transfer rotation from one shaft to another. When a small gear drives a larger gear, the output usually turns more slowly but with greater torque. When a larger gear drives a smaller one, the output turns faster but provides less torque.

Count the teeth on the driving and driven gears. The ratio gives you a way to predict how their speeds compare. Mark one tooth on each gear, turn the input through a full revolution and count what happens at the output.

The winding drum

The drum converts rotation into the movement of the cable. Each revolution winds or unwinds a length related to the drum’s circumference. A wider drum retrieves more cable per turn, but lifting the same load may require more torque.

This creates an engineering trade-off: a design can favour speed, force or compact size, but rarely maximises all three at once.

Pulleys guide and share force

A fixed pulley changes the direction of a force. A moving pulley can share the load across more than one supporting section of cable, reducing the input force in an ideal system. Real systems also include friction, cable weight and other losses.

Investigate the model

Try a sequence of small tests:

1. Lift the same load and count the crank turns needed.
2. Time the lift over the same distance.
3. Change one gear arrangement or drum condition if the model allows it.
4. Compare speed, control and the effort you feel at the handle.
5. Explain where energy might be lost through friction.

Safety is part of the engineering

A real mine hoist carries people or heavy material, so braking, inspection, communication and controlled operation are essential. The model demonstrates principles; it is not a lifting device for real loads. Keep fingers, hair and loose clothing away from moving gears and cord.