As early as the 18th century, micrometers stepped onto the stage of manufacturing in the development of machine tool industry. To this day, the micrometer remains one of the most versatile precision measuring tools in the workshop. Today, the editor will give you a brief introduction to the birth and development history of the micrometer
First Attempts to Measure Length with Threads
Humans first used the thread principle to measure the length of objects in the 17th century. In 1638, W. Gascogine, an astronomer in Yorkshire, England, used the thread principle to measure the distance of stars. Later, in 1693, he invented a measuring ruler called the "caliper micrometer".
This is a measuring system with a threaded shaft attached to a rotating handwheel at one end and movable jaws at the other. Measurement readings can be obtained by counting the rotations of a handwheel with a reading dial. The week of the reading dial is divided into 10 equal parts, and the distance is measured by moving the measuring claw, which realizes the first attempt of human beings to measure the length with the screw thread.
Caliper micrometer invented by H. Gascoigne
Watt and the first benchtop micrometer
A century after Gascogine invented his measuring instrument, in 1772 James Watt, the inventor of the steam engine, invented the first benchtop micrometer, a key factor in its design being thread-based magnification. The U-shaped structure design first used by James Watt later became the standard of the micrometer, and the history of the micrometer would be interrupted here without him.
James Watt's Bench Micrometer (Replica)
The "Judge" invented by the father of the machine tool
In the early 19th century, Sir Henry Mausdlay, known as the "father of machine tools", also left his footprints in the history of measuring instruments. His invention of the bench micrometer "The Justice" was able to measure the most precise dimensions at the time and is considered the beginning of precision measuring instruments.
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Mausdlay's Benchtop Micrometer "The Justice"
Sir Whitworth was the first to commercialize the micrometer
However, James Watt and Mausdlay's benchtop micrometers were largely for their own use. Precision measuring instruments were not commercially available until the latter part of the 19th century. Sir Joseph Whitworth, who invented the famous "Whitworth thread", became the leading figure in promoting the commercialization of micrometers.
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Sir Whitworth's "millionth of an inch" measuring device
The Birth of the Modern Micrometer
The modern standard micrometer features a U-shaped construction and one-handed operation. Micrometers are a common design used by many manufacturers. Add Xiaobian WeChat Yuki7557 to get 10G CNC tutorial, this typical design can be traced back to 1848, French inventor J. Palmer obtained a patent called Palmer system. Almost all modern micrometers follow the basic design of the Palmer system, such as U-shaped structure, sleeve, sleeve, mandrel and anvil. Palmer's contribution to the history of the micrometer is immeasurable.
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Palmer micrometer on display at the Paris International Exposition
The evolution of the micrometer
Brown & Sharpe of the American B&S Company visited the Paris International Exposition held in 1867, where they saw the Palmer micrometer for the first time and brought it back to the United States. Brown & Sharpe carefully studied the micrometer they had brought back from Paris and added two mechanisms to it: a mechanism for better control of the spindle and a spindle lock. They produced the pocket micrometer in 1868 and brought it to market the following year.
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Pocket micrometers for measuring plate thickness by Brown & Sharpe
Since then, the necessity of micrometers in machinery manufacturing workshops has been accurately predicted, and micrometers suitable for various measurements have been widely used with the development of machine tools.
