The English word corresponding to the screw is screw. This word in the last hundreds of years the meaning of the attack has been relatively large changes, at most in 1725, it is the meaning of "mating".
In addition to the name of learning, small screws from being created to be the rule for clockwise tightening, counterclockwise release, experienced thousands of years of time.Hardware furniture ScrewsThe screws in it have to be tightened clockwise, do you always know? Suppose you don't know, please look down.
Six of the most complex machine things are: screws, tilt surfaces, levers, pulleys, wedges, wheels, axles. The screws are ranked among the six complex machines, but to put it bluntly is nothing more than an axis and a tilt stereo that surrounds it.
By the past, the screws have now unfolded the standard scale. The typical way to use screws is to tighten it with a clockwise rotation (absolutely, with a counterclockwise rotation to loosen it).
Screws are not a lasting creation of history. It took 2000 years to create something that we turned a blind eye to, and it was just a feeble example of what was called high-minded. Everyone trusted Plato's enemies, and Tarentum's Archiytas created the screws in 400 BC. Archimedes first thought that you could use screws to connect things together, or you could use it to lift water. The Romans used bronze and silver as data, and the craft cut out the screws. In the later stages, people use a variety of screws to squeeze olive oil, irrigation canals, to remove the bilge water, of course, also used to connect things together.
Tighten the secondary by the right-hander resolution, however, since the screws at the beginning of the creation are artificially created, the fineness of its screws is not common, usually by the craftsman's own love resolution. By the middle of the 16th century, Jaques Besson, a French palace engineer, had created lathes that could be cut into screws, a technique that had since been introduced for 100 of years. The Englishman Henry Maudsley created the ancient lathe in 1797, and with it, the fineness of the thread improved clearly. Nevertheless, the size and fineness of the screws are still not divided.
This situation was lost in 1841. Joseph Whitworth, an apprentice to Maudsley, submitted an article to the Institute of Municipal Engineers calling for the integration of screw types.
He made a two-point proposition:
1, screw thread inclination should be 55° as the standard;
2, do not think about the diameter of the screws, the number of filaments per foot should take a positive specification. When the screws are tightened, it seems to be an unwritten rule, because the right-hander uses the right hand to twist the screws clockwise when the strength is greater, and the large minority is the right-hander (the share is about 70%-90%).
Although the screws are small, the late demand n kinds of machine tools and n+1 tools are made in any case, Whitworth's ideas are very popular. Shortly after his proposal, the whole of England chose the round bottom tip of the screw specification, the 1860s the United States, Canada also selected this specification. However, screws are not easy to manufacture due to the production process "demand three kinds of tools two kinds of machine tools."
In order to deal with questions about the production of British norms, William Sellers, an American, created a flat-top leveling thread in 1864, a small change that made it only a tool and machine tool for screws to make. More convenient, more complex, and lower prices. The threads of the sellers screws prevailed in the United States and quickly became the norm for the use of American railway companies (during which two railway companies were busy building intercontinental railways). The British insist on the use of Whitworth's slightly picky screws, but these different norms in World War II is still added a lot of trouble.
At one point the British, Canadian and American army once put their equipmentElectromechanical hardware ScrewsGot mixed up with the repair parts. After the war, Canada, the United States and Britain reached an agreement in 1949 to agree on the specification of the thread-according to the British, the choice of 60 degree inclination. A little later, Britain turned to the metric balance of bits and pieces. In the 1960, the country's international unit of units and ISO metric specification screws were fitted with threads with a 60 degree inclination. Globally, the clockwise rotation screws based on the metric are now in the specification. But in the United States, about 60% threads are still used according to the inch screw specification.
- Hardware nut Manufacturers let you know a variety of screwdrivers
- The difference between hardware furniture screws (screws, screws, bolts, nuts), etc.
- Process and process of producing hardware nut manufacturers
- Stainless steel screw manufacturer's quality supervisor how to monitor screw quality
- Hardware screw nut (knowledge of automobile special screws)
- Hardware casing hardware fastener industry small knowledge, quenching cause analysis and relative prevention
- Common sense of combination hardware furniture screws
- Standard and application of hardware fastener manufacturers
- Four trends in the future development of hardware and electrical screws
- Summary of basic knowledge of hardware waterproof casing
- ISO28000 Logistics/Transportation supply chain safety management training