Commerical Lifts Benguet, Philippines
Philippine Elevators – Believes the invention of the elevator can rightly be described as one of the most important machines of all time. Let’s take a closer look at Philippine elevators and find out how they work!
What is an elevator Benguet, Philippines
A typical, modern, electronically controlled elevator. If you wait for the cars to move out of the way, you can often see some of the workings and figure out which bits do what. From the view point of someone traveling from the lobby to the 18th floor, an elevator is simply a metal box with doors that close on one floor and then open again on another.
For those of us who are more curious, the key parts of an elevator are:
- One or more cars “metal boxes” that rise up and down.
- Counterweights that balance the cars.
- An electric motor that hoists the cars up and down, including a braking system.
- A system of strong metal cables and pulleys running between the cars and the motors.
Various safety systems to protect the passengers if a cable breaks.
- In large buildings, an electronic control system that directs the cars to the correct floors using a so called “elevator algorithm” to ensure large numbers of people are moved up and down in the quickest, most efficient way.
How Elevators Use Energy – Benguet, Philippines
Scientifically, elevators are all about energy. To get from the ground to the 18th floor walking up stairs you have to move the weight of your body against the downward-pulling force of gravity. The energy you expend in the process is “mostly” converted into potential energy, so climbing stairs gives an increase in your potential energy “going up” or a decrease in your potential energy “going down”. This is an example of the law of conservation of energy in action. You really do have more potential energy at the top of a building than at the bottom, even if it doesn’t feel any different.
To a scientist, an elevator is simply a device that increases or decreases a person’s potential energy without them needing to supply that energy themselves, the elevator gives you potential energy when you’re going up and it takes potential energy from you when you’re coming down. In theory, that sounds easy enough, the elevator won’t need to use much energy at all because it will always be getting back as much “when it goes down” as it gives out “when it goes up”. If all the elevator had were a simple hoist with a cage passing over a pulley, it would use considerable amounts of energy lifting people up but it would have no way of getting that energy back, the energy would simply be lost to friction in the cables and brakes “disappearing into the air as waste heat” when the people came back down.
How Much Energy Does An Elevator Use – Benguet, Philippines
Elevators don’t just hang from a single cable… There are several strong cables supporting the car in case one breaks. If the worst does happen, you’ll find there’s often an emergency intercomtelephone you can use inside an elevator car to call for assistance.
THE COUNTERWIEGHT – Benguet, PHILIPPINES
The counterweight rides up and down on wheels that follow guide tracks on the side of the elevator shaft. Each car has its own counterweight so the cars can operate independently of one another. On this picture, you can also see the doors on each floor that open and close only when the elevator car is aligned with them.
In practice, elevators work in a slightly different way from simple hoists. When the elevator goes up, the counterweight goes down and vice versa, which helps us in four ways:
- The counterweight makes it easier for the motor to raise and lower the car just makes it much easier to lift someone’s weight compared to lifting them in your arms. Thanks to the counterweight, the motor needs to use much less force to move the car either up or down. Assuming the car and its contents weigh more than the counterweight, all the motor has to lift is the difference in weight between the two and supply a bit of extra force to overcome friction in the pulleys and so on.
- Since less force is involved, there’s less strain on the cables, which makes the elevator a little bit safer.
- The counterweight reduces the amount of energy the motor needs to use. This is intuitively obvious to anyone who’s ever sat on a see saw, assuming the see saw is properly balanced, you can bob up and down any number of times without ever really getting tired—quite different from lifting someone in your arms, which tires you very quickly. This point also follows from the first one: if the motor is using less force to move the car the same distance, it’s doing less work against the force of gravity.
- The counterweight reduces the amount of braking the elevator needs to use. Imagine if there were no counterweight, a heavily loaded elevator car would be really hard to pull upwards but, on the return journey, would tend to race to the ground all by itself if there weren’t some sort of sturdy brake to stop it. The counterweight makes it much easier to control the elevator car.
The safety brake Benguet, Philippines
Everyone who’s ever traveled in an escalator has had the same thought, what if the cable holding this thing suddenly snaps… Rest assured, there’s nothing to worry about. If the cable snaps, a variety of safety systems prevent an elevator car from crashing to the floor. Each car ran between two vertical guide rails with sturdy metal teeth embedded all the way up them. At the top of each car, there was a spring loaded mechanism with hooks attached. If the cable broke, the hooks sprung outward and jammed into the metal teeth in the guide rails, locking the car safely in position.
Speed Governors Benguet, Philippines
Most elevators have an entirely separate speed regulating system called a governor, which is a heavy flywheel with massive mechanical arms built inside it. Normally the arms are held inside the flywheel by hefty springs, but if the lift moves too fast, they fly outward, pushing a lever mechanism that trips one or more braking systems. First, they might cut power to the lift motor. If that fails and the elevatorlift continues to accelerate, the arms will fly out even further and trip a second mechanism, applying the brakes. Some governors are entirely mechanical; others are electromagnetic, still others use a mixture of mechanical and electronic components.
Other safety systems – Benguet, Philippines
Modern elevators have multiple safety systems. Like the cables on a suspension bridge, the cable in an elevator is made from many metal strands of wire rope twisted together. Most elevators also have multiple, separate cables supporting each car, so the complete failure of one cable leaves others functioning in its place. Even if all the cables break, this system will still hold the car in place.
Finally, if you’ve ever looked at a transparent glass elevator, you’ll have noticed a giant hydraulic or gas spring buffer at the bottom to cushion against an impact if the safety brake should somehow fail.
How does a hydraulic elevator work – Benguet, Philippines
Elevators that work with cables and wheels are sometimes called traction elevators, because they involve a motor pulling on the car and counterweight. Not all elevators work this way, however. In small buildings, it’s quite common to find hydraulic elevators that raise and lower a single car using a hydraulic ram, a fluid filled piston similar to the ones that operate construction machines like bulldozers and cranes. Hydraulic elevators are mechanically simpler and therefore cheaper to install, but since they typically don’t use counterweights, they consume more power raising and lowering the car. Sometimes the hydraulic ram is installed directly underneath the car and pushes it up and down. Alternatively, if there isn’t room to do that, the ram can be mounted to the side of the lift shaft, operating the car using a system of ropes and sheaves. More complex elevators, like the one shown here, use multiple hydraulic cylinders and counterweights.