An elevator type that uses a hydraulic jack driven by a pump and pressurised oil to raise and lower the car, without the need for overhead traction machinery.
Full Definition
A hydraulic elevator raises the car by pumping oil from a reservoir into a hydraulic cylinder (jack) under the car or connected via ropes. The pump motor forces oil into the cylinder to ascend; descent is controlled by a lowering valve that releases oil back to the reservoir under gravity. Two main configurations exist: direct-acting (piston directly below the car) and roped-hydraulic (piston connected via ropes to a ratio of 2:1 or greater, reducing cylinder travel). Hydraulic elevators are suited to low-rise applications of 2–6 floors at speeds up to 0.63 m/s. They require a machine room at or near the lowest floor for the pump unit and oil reservoir. EN 81-20 covers hydraulic lifts alongside traction lifts, while EN 81-2 (now withdrawn) was the earlier dedicated standard. Key safety devices include a rupture valve on the cylinder inlet (preventing descent on pipe failure) and a parachute safety gear on roped variants.
