A glass lift car in a steel and glass shaft above an atrium floor
AI-generated editorial illustration created for BrainiLab.

A hidden partner

In a traction elevator, a motor turns a wheel that grips the ropes or belts connecting the cabin to a counterweight. When your cabin goes up, the counterweight goes down. Otis describes it as a see-saw tucked away in the lift shaft.

That wheel is called a sheave. It transfers the motor’s motion to the ropes by gripping them, a bit like your shoes grip the floor as you walk.

Why balance helps

Picture two buckets at opposite ends of a rope over a wheel. With similar amounts of water in both, a small pull can raise one bucket while the other descends. The descending bucket helps lift its partner.

A lift’s passengers change from trip to trip, so the balance changes too. The counterweight still offsets part of the load, while the motor and its controls move the cabin and regulate its speed. Nidec’s guide shows where the counterweight and drive sit.

A lift that pushes from below

In a direct hydraulic lift, an electric pump pushes oil into a cylinder. The pressure moves a piston upwards and lifts the cabin. Otis describes how the cabin lowers as oil is allowed to flow out again.

One lift uses a gripping wheel and a counterweight. The other pushes with fluid pressure. If you’d like to follow that second idea into the kitchen, see how a pressure cooker works for a different use of pressure.