Top 100 Scientific Inventions That Changed The World -P2. Screw.

28-02-2019

(Wcsas.world) A screw is a type of fastener, sometimes similar to a bolt (see Differentiation between bolt and screw below), typically made of metal, and characterized by a helical ridge, known as a male thread (external thread) or just thread.

A screw is an inclined plane wrapped around a nail. Some screw threads are designed to mate with a complementary thread, known as a female thread (internal thread), often in the form of a nut or an object that has the internal thread formed into it. Other screw threads are designed to cut a helical groove in a softer material as the screw is inserted. The most common uses of screws are to hold objects together and to position objects.

 

 

 

 

In antiquity, the screw was first used as part of the screw pump of Sennacherib, King of Assyria, for the water systems at the Hanging Gardens of Babylon and Nineveh in the 7th century BC.

The screw was later described by the Greek mathematician Archytas of Tarentum (428 – 350 BC). By the 1st century BC, wooden screws were commonly used throughout the Mediterranean world in devices such as oil and wine presses. Metal screws used as fasteners did not appear in Europe until the 1400s.

 

 

In 1770, English instrument maker, Jesse Ramsden (1735-1800) invented the first satisfactory screw-cutting lathe. The British engineer Henry Maudslay (1771-1831) patented a screw-cutting lathe in 1797; a similar device was patented by David Wilkinson in the United States in 1798.

 

 

In 1908, square-drive screws were invented by Canadian P. L. Robertson, becoming a North American standard. In the early 1930s, the Phillips head screw was invented by Henry F. Phillips.

According to wikipedia

 


Xiang Yun (Editor) - World Creativity Science Academy - WCSA