You’ve probably stepped onto an elevator hundreds of times, but have you ever questioned how it works? How it balances your weight to keep you from falling? After taking a look behind the scenes, you may never look at an elevator ride the same way again.
In 1861, Elisha Graves Otis created what would be the first iteration of the elevator that we use today. It was the first time anyone had created an elevator equipped with a safety feature, a device to keep it from falling if the lifting rope broke. Today, there are two types of elevators that are typically used – and lucky for us, both come equipped with safety features standard.
The Hydraulic Elevator
Hydraulic elevators are comprised of a cylinder, hydraulic fluid, a piston, a fluid reservoir, a rotary pump, and a valve. When the elevator needs to go up, the pump sends fluid into the cylinder which closes the valve. This pressurizes the fluid and moves the piston up. To go down, the valve opens and fluid is released back into the reservoir. The machine room to house the mechanism for a hydraulic elevator is typically located on the lowest floor.
Safety Because of the hydraulic arm, the elevator car is never suspended in the air. It is always being held up, no matter where the elevator is. There are fewer moving parts than a roped elevator, so as long as you get your elevator maintained regularly, it’s completely safe.
The Roped Elevator
Roped elevators can travel much quicker than hydraulic elevators. These elevators include a counterweight to balance the car, the electric motor, breaks, metal chains and pulleys, and a safety system. It’s basically an elaborate rope and pulley system. The ropes are wrapped around a sheave that is connected to the electric motor. When the motor turns one way, the car goes up, and when it turns the other way, the car goes down. The ropes are connected on the other side to a counterweight that weighs as much as 40% of the elevator’s capacity. Typically all of this equipment is housed in a machine room above the elevator shaft.
Safety Although one rope can easily carry the weight of the car and the counterweight Every roped elevator is built with multiple ropes. This is the first line of safety. Elevators are built with between four and eight ropes, typically, so if one breaks, there are plenty more to ensure the car doesn’t fall. Other than the ropes, the cars also have built-in braking systems just in case.
If this isn’t already more than you want to know about how an elevator works, feel free to contact us with any questions you may have!