A brief history of door and board lifters
A brief history of door and board lifters |
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Door and board lifters are simple levers which are operated by foot to lift a load a few centimetres from the ground. Levers are basic devices made up of a rigid rod or beam with a pivot point. They’re used to increase, or “amplify”, an input force so as to produce a greater output force. | |||
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A door and board lifter is what’s known as a first-class lever, where the pivot point is situated between the input and the load. They produce a large force over a small distance at the output end by applying a small force, over a greater distance, at the input end. Other tools which incorporate this type of lever include crowbars, pliers and scissors. | |||
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Levers are believed to date from prehistoric times. It’s thought that the Ancient Egyptians used levers to move and raise their obelisks, which were made from solid stone and usually weighed more than 100 tons. It’s also supposed they used levers to help them place the massive stones used to construct the pyramids into their final positions. | |||
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Levers were first written about around 260 BC by the Ancient Greek inventor Archimedes. He explained the principle of how levers work by developing a mathematical model, which he describes in On the Equilibrium of Planes. This is known as the Archimedes Law of Levers. | |||
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Archimedes is often credited with saying: “Give me a lever long enough and a fulcrum on which to place it and I shall move the world”. This implies that any weight can be lifted by an individual, if they have a long enough lever.
For more information see: How does a door or board lifter work? |
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