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The screw was also apparently applied to drilling and moving materials (besides water) around this time, when images of augers and drills began to appear in European paintings. [12] The complete dynamic theory of simple machines, including the screw, was worked out by Italian scientist Galileo Galilei in 1600 in Le Meccaniche ("On Mechanics").
A simple machine is a mechanical device that changes the direction or magnitude of a force. [1] In general, they can be defined as the simplest mechanisms that use mechanical advantage (also called leverage) to multiply force. [2] Usually the term refers to the six classical simple machines that were defined by Renaissance scientists: [3] [4 ...
An assortment of screws, and a US quarter for size comparison A wood screw: a) head; b) non-threaded shank; c) threaded shank; d) tip The six classical simple machines. A screw is an externally helical threaded fastener capable of being tightened or released by a twisting force to the head. The most common uses of screws are to hold objects ...
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The hand axe is the first example of a wedge, the oldest of the six classic simple machines, from which most machines are based. The second oldest simple machine was the inclined plane (ramp), [6] which has been used since prehistoric times to move heavy objects. [7] [8] The other four simple machines were invented in the ancient Near East. [9]
The screw thread concept seems to have occurred first to Archimedes, who briefly wrote on spirals as well as designed several simple devices applying the screw principle. Leonardo da Vinci understood the screw principle, and left drawings showing how threads could be cut by machine. In the 1500s, screws appeared in German watches, and were used ...
The screw, the last of the simple machines to be invented, [22] first appeared in Mesopotamia during the Neo-Assyrian period (911–609 BC). [21] The Assyrian King Sennacherib (704–681 BC) claims to have invented automatic sluices and to have been the first to use water screw pumps , of up to 30 tons weight, which were cast using two-part ...
The screw pump is the oldest positive displacement pump. [1] The first records of a water screw, or screw pump, date back to Hellenistic Egypt before the 3rd century BC. [1] [3] The Egyptian screw, used to lift water from the Nile, was composed of tubes wound round a cylinder; as the entire unit rotates, water is lifted within the spiral tube to the higher elevation.