Hobbies And Interests
Elevator History
All elevators began as simple hoist mechanisms, using ropes or chains. Hoist mechanisms were invented that either pushed or pulled the elevator car up and down as elevator designs evolved. The safety elevator was invented in 1853, creating the first elevator with an emergency stop for preventing falls within the hoistway. In 1878, the hydraulic elevator was introduced, followed by the electric elevator invention in 1880. Currently, new elevators use microprocessors and computer controls for guiding the elevator's travels.
Hydraulic Elevators
Hydraulic elevators use hydraulic-fluid pressure against the elevator car for movement. A large hydraulic piston, either above ground or underground, pushes against the car's bottom for motion. Alternatively, a hydraulic piston can be combined with ropes installed above the elevator car for motion. However, hydraulic systems have limitations. The piston's size can only typically lift up to seven stories. Otherwise, the piston's length would have to be considerably longer, compromising the elevator's design integrity and costing much more for initial construction. In addition, hydraulic mechanisms tend to run more slowly than other hoist choices, such as traction systems.
Traction Elevators
Traction elevators locate all operating mechanisms above the elevator car. Traction uses steel ropes pulled by heavy-duty pulleys. The ropes reside in deep grooves so that they do not accidentally slip out of the pulley during operation. The motor moving the elevator can use gears attached to the pulley for hoisting, called a geared traction system. In contrast, gearless traction systems install the motor directly to the pulley mechanism for motion. Gearless traction is typically installed for buildings more than 20 stories tall, providing 500-feet-per-minute speeds. Geared traction is commonly used up to building heights of 300 feet with the same speed generation.
Gearless Benefits
Gearless traction systems do not require a machine room above the elevator. Typical traction elevators, as well as hydraulic/rope systems, require a space above the hoistway for housing gears. Gearless traction does not use gears, resulting in more building space for other uses. Additionally, the elevator's motion is more comfortable compared to geared traction, as well as using less energy for operation.