scissor lift
Elevators raised and lowered from underneath by an extendable lattice of criss-crossed folding beams.
A scissor lift elevator is a vertical transportation cab which is raised and lowered from underneath, somewhat like a traditional hydraulic elevator, except that instead of a hydraulic cylinder the extendable mechanism is a folding lattice of criss-crossed beams similar to a pantograph. The entire mechanism extends upward when pressure is applied to the lowest members.
Although portable scissor lifts are common for outdoor work, as an elevator type scissor lifts are quite rare.
The crossed members unfold to increase the height of the supporting mechanism beneath the cab. The scissor geometry distinguishes this lift mechanism from a direct hydraulic lifting cylinder.
Related definitions
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hydraulic
Elevators raised by a fluid-powered cylinder-and-piston mechanism and lowered by controlled release of fluid. -
paternoster
Doorless vertical lift cabins carried upright around a continuously moving loop with upward and downward shafts. -
platform lift
A platform raised and lowered mechanically to transport persons and cargo between different levels. -
rack and pinion
Elevators that climb along a toothed rack through the rotation of pinion gears engaged to the rack. -
traction
Elevators raised and lowered along tracks by cables, using a counterweight for balance.