Hydraulic Home Passenger Elevator

Essentially, they work because a pump pushes oil into a hydraulic cylinder which has a piston inside. This pressure placed on the piston is what lifts the elevator car up. When the pressure is released by a downward descent the oil is pushed out of the piston, the pressure lowers and so does the lift. Hydraulic elevators are elevators which are powered by a piston that travels inside a cylinder. An electric motor pumps hydraulic oil into the cylinder to move the piston. The piston smoothly lifts the elevator cab. Electrical valves control the release of the oil for a gentle descent.