A Brief History of the Micrometer a Brief History of the Micrometer

R257 A Brief History of the Micrometer A Brief History of the Micrometer

Contents

Foreword 2 History of Machine Tools and Micrometers 4 Chapter I: The Early Period 6 Threads Used in Linear Measurements First Attempt to Measure Length with Threads 6 Watt’s Tabletop Micrometer 7 "Lord Chancellor" by the Father of Machine Tools 8 The First Commercial Measuring Machine 9 Chapter II: The Bronze Age 10 Creating the Basic Design of a Micrometer The Birth of the Modern Micrometer 10 Born in France, Raised in America 11 Micrometers for Plate Thickness Measurements 12 Micrometers for All Applications 13 Chapter III: The Rise of Industry 14 Progress in Japan Expanding Technologies in Japan 14 Domestic Manufacturers Start R & D 15 Micrometers by Mitutoyo 16 Micrometers During the War 17 Chapter IV: Rise of "Made in Japan" 18 Period of Worldwide Expansion Hardships During and After the War 18 From Reconstruction to Mass Production 19 Innovations to Meet Industry Needs 20 Maturity Through Intense Competition 21 Chapter V : A Partner of Information System 22 Moving into the Silicon Age From Reading Graduations to Looking at a Display 22 Advancements in Digital Displays 23 Merits of Data Output 24 Completing a Full Circle 25 Chapter VI: The Future of Micrometers 26 The Next generation of micrometers A Revolutionary Advancement in Micrometer Technology 26 Pioneering Design: 2mm Feed Per Revolution 28 Index 31

1 A Brief History of the Micrometer Foreword

ver 4.6 billion years ago, Planet Earth was formed. OOur distant ancestors debuted only 5 million years ago. Though primitive, they were believed to have used stones as tools. A scant 500 thousand years ago, modern man (homosapiens) roamed the land. Today, their descendants use tools to build large structures, design high speed vehicles, and manufacture microscopic parts too small for the human eye to see.

Making this possible are fabricating devices called Machine Tools. Also known as the 'Mother Machine', they are one of the foundations of industrial progress. Originally created to meet the manufacturing needs of watchmakers, their use has extended to all aspects of manufacturing.

To meet and ensure design specifications, it was necessary to incorporate measuring instruments into the production line.

A Brief History of the Micrometer 2 A Brief History of the Micrometer

As Machine Tools grew to become one of the essential elements of the manufacturing industry, so did the accompanying measuring instruments such as the Micrometer.

Invented in the 18th Century, the Micrometer was initially bulky and restricted to the tabletop. Over time, newer models became compact enough to be operated by one hand and still provide outstanding measuring accuracy.

This booklet covers the birth and evolution of Micrometers: tools essential to the progress of modern industry.

3 A Brief History of the Micrometer History of Machine Tools and Micrometers

Year Micrometers Industry and Machine Tools

BC period c.200BC. .Screw thread invented c.300BC Oldest turning machine found in Egypt

Before 15th Century Leonardo da Vinci proposed lathe 1600 16th Century Gear-cutting machine developed

17th 1639 W. Gascoigne invented a micrometer caliper 1638 W. Gascoigne utilised screw threads to observe stars. Century comprising of jaws and scale The first recorded application of screw threads

18th 1772 J. Watt invented the table-top micrometer 1713 J.Maritz invented the vertical boring machine Century 1763 Pertherwood invented a special turning machine to cut threads on cylinder surfaces 1765 J. Watt granted a patent for the steam engine 1775 J. Wilkinson invented a boring machine to cut internal cylinders, contributing to increased power of steam engines.

19th 1805 H.Maudslay invented the table-top micrometer c.1800 H. Maudslay, the father of machine tools, invented Century called ‘Lord Chancellor’ reciprocating gear-cutting lathe 1848 J. Palmer received a patent for his micrometer 1827 E. Whitney invented the horizontal milling machine called ‘Palmer System’ in France 1830 B. Thimonnier invented the sewing machine 1855 J. Whitworth invented a horizontal calibration 1838 R. Buchanan invented the radial boring machine machine and made it available for sale 1868 Brown & Sharpe invented pocket-sized micrometers for measuring plate thicknesses

19th 1877 Victor Machine placed an ad for their micrometer 1876 N. Otto invented the combustion engine Century in the inaugural issue of American Machinist

1920 ~ 1935 Several Japanese manufacturers start 1903 Wright brothers succeeded in their first flight producing micrometers 1907 H. Ford introduced the Model T, the first car to be mass- 1938 Mitutoyo starts producing Micrometers produced 1947 Mitutoyo restarts producing Micrometers after 1941 US suspends export of machines to Japan WWII 20th 1952 MIT produced first NC milling machine Century 1953 Mitutoyo produced the 3 meter outside micrometer, the largest in the world 1956 Fanuc produced the NC turret punch press machine, the first in Japan 1969 Mitutoyo started producing 3-pointed inside micrometers 1958 US Kerney Trecker produced first machining center 1979 First digital Micrometer in Japan introduced by 1982 Japanese machine tools are recorded as the largest in Mitutoyo terms of value in the world

2003 Mitutoyo introduced its first coolant-proof 2001 Kyoto Protocol to reduce the emission of greenhouse micrometer gases completed 21st Century 2004 Mitutoyo introduced its improved ratchet- 2006 Japanese Machine tool industry achieved the largest thimble micrometer annual sales worth $14.3 billion, exceeding 1990 records

A Brief History of the Micrometer 4 A Brief History of the Micrometer

Chapter I: The Early Period

First Attempt to Measure Length with Threads

H. Gascoigne's Micrometer Caliper

easurement started as early threads to directly measure the objects. Mas 5000 years ago when the Nevertheless, his method of measuring Egyptians built the Pyramids. distances by thread displacement was The principle of screw threads similar to modern methods. was used by the Greeks to raise water In the following year, he invented from a lower to a higher level. The a measuring gauge called the "Caliper idea of using these same threads for Micrometer". The system comprised measurement did not exist then. of a rotating handle attached to the It was during the 17th century end of a threaded rod connected to a when threads were utilised to measure movable jaw. A reading was achieved the length of objects. In 1638, the by counting the revolutions of the English astronomer W. Gascoigne used handle against an attached disc. The the principle of threads to measure disc divided one rotation into 10 equal the distance of stars. Fine-adjusting parts, thus he could measure the his telescope by screw threads, he distance covered by the moving jaw measured the stars in the nightly sky. with accuracy. However in this method, he did not use

5 A Brief History of the Micrometer Threads Used in Linear Measurements

Watt’s Tabletop Micrometer

James Watt's Tabletop micrometer (replica)

ore than a century after graduated disc indicates revolution MGascoigne invented his measuring of threads, while the smaller one instrument, James Watt of the steam indicates fractions of an inch. The engine fame invented the first bench- smallest reading on the large dial face type micrometer. A key concept of his was 1/10000 of an inch. design was magnification based on At the time, gauges were generally threads. In all history books, his name large and cumbersome to operate, and is always mentioned, and with good for that reason his gauge was designed reason: Without Watt, a history of to be used on a workbench. micrometers cannot be written. James Watt was the first to His invention, briefly described, employ a "U"-shaped frame, and can consists of a rack-and-pinion mecha- be recognised as a standard design for nism connected to rotating threads. In modern micrometers. However, for a practice, a measuring blade attached to long period of time following Watt’s the rack advances and makes contact invention, the "U"-shaped frame was with an object to be measured. The not used, and micrometers using this movement of threads was measured design did not appear in the market. by a pair of graduated discs attached to the end of the threads. The larger

A Brief History of the Micrometer 6 A Brief History of the Micrometer

"Lord Chancellor" by the Father of Machine Tools

Maudslay's "Lord Chanceller" a table-top micrometer

n the early part of the 19th century, held in high regard, second only to ISir Henry Maudslay was known as Leonardo da Vinci. “The Producer of Best Machine Tools“ Maudslay also left his mark in London. in measuring instruments. His His screw-cutting lathe invented table-top micrometer, called "Lord circa 1800 was said to be the origin of Chancellor", was the most precise modern Machine Tools. Moreover, he of that day and considered as the produced a dedicated machine to mass beginning of precision measuring manufacture pulleys used in sailing instruments. ships. He also conceived the idea of It was a brass four-legged table-top modern machine shops, and provided device about 40cm long, and featured input for the development of surface a pair of blocks to sandwich objects. grinders and milling machines. Below the saddle was an opening, and He was well respected in to its edge were 1/10000 inch gradu- England and was called the "Father ations. It was so precise that it was of Machine Tools". In the field of retested years later in 1918 and was machine tools, Maudslay's name is still found to be accurate.

7 A Brief History of the Micrometer Threads Used in Linear Measurements

The First Commercial Measuring Machine

Whitworth's "Millionth of an inch" measuring machine

ames Watt and Maudslay's table- well known for the threads bearing his Jtop micrometers were largely name — Whitworth Thread. Whitworth limited to private use. It was only during was also excellent in managing the later part of the 19th century that machine shop operations. He also precision measuring machines were created a method to make flat surface made available for sale. plates, and simplified maintenance It was Sir Joseph Whitworth by using standardised screw threads. who introduced one of the most He always experimented and tested a remarkable instruments of that period: prototype, and his decision was based his "millionth of an inch" (0.254µm) on supporting data. His knowledge measuring machine, many of which aided in streamlining manufacturing were sold to the general public. Today, operations and establishing analytical a 1.8 meter-long Whitworth measuring control systems. machine is displayed at the Mitutoyo He was a frontrunner in the mid Museum. 19th century and his contributions left Sir Whitworth was one of the giants an indelible mark in the development in engineering after Maudslay: He was of Machine Tools.

A Brief History of the Micrometer 8 A Brief History of the Micrometer

Chapter II: The Bronze Age

The Birth of the Modern Micrometer

Palmer's Micrometer displayed in Paris

oday's standard Micrometer micrometer. Tfeatures a "U"-shaped frame Modern micrometers closely and one handed operation. Many follow the System Palmer's basic design manufacturers share this common of a "U"-shaped frame, thimble, sleeve, micrometer design. The origin of spindle, anvil, etc. The reading edge of this design can be traced back to the thimble was slightly tapered down the French inventor J. Palmer who to meet the graduations on the sleeve. received his patent in 1848. It was The circumference of the thimble called the “System Palmer”. was divided into 20 equal parts, thus As stated earlier, using screw providing accuracy of up to 0.05mm. threads for measuring linear distances Brown and Sharpe of B&S Co. has its origin in Gascoigne's invention visited the International Exposition in in 1638. Essentially, Palmer used Paris in 1867. It was there that they the same principle in his compact both witnessed the System Palmer hand-held micrometer. However, for the first time and made the his design was more advanced and decision to bring it back to America. marked the beginning of modern This encounter in Paris led to a micrometers. Palmer's contribution successful introduction of micrometers was immeasurable in the history of the across the Atlantic.

9 A Brief History of the Micrometer Creating the Basic Design of a Micrometer

Born in France, Raised in America

he System Palmer brought imperfections: they could improve upon Tback to America by Brown and the original design by replacing it with a Sharpe was not perfect in workman- finer 40 threads per inch spindle. ship. It employed 1mm pitch threads The System Palmer was brought and was accurate up to 0.05mm. across the Atlantic by two American While the drawings of Palmer's patent entrepreneurs, and it was in America application were carefully rendered, where improvements in micrometer the design could be improved. For design took place in earnest. It was the example, it offered no spindle clamp. countless new innovations added to it More importantly, the graduated lines in America that made the micrometer were not equally spaced. so popular today. The modern However, Brown and Sharpe micrometer was truly born in France did not pay attention to these minor and raised in America.

A Brief History of the Micrometer 10 A Brief History of the Micrometer

Micrometers for Plate Thickness Measurements

Brown & Sharpe's pocket micrometer for plate thickness

icrometers were needed in The appearance and principles MAmerica for a good reason: used in the prototype were close to what Manufacturers and customers could a micrometer should be. However, the not agree on the thickness of brass reading of dimensions was complicated. plates, due to the fact that they each The operator was required to interpret used their own special gauges to take the measured values based on the their readings. meeting point of the lines. This design The chief inspector of Bridgeport proved to be unsuccessful. Brass Plate Company was S. Wilmot. Brown and Sharpe studied the He produced six trial gauges whose micrometer they brought back from design was influenced by the table-top Paris, and added two features: a micrometer produced by a company in mechanism to hold spindle threads New York. It was Wilmot who present- better, and a spindle clamp. Their ed one of his prototypes to the Brown tiny pocket-type micrometer was and Sharpe Company, and suggested produced in 1868 and introduced in that they market it for general use. the market the following year.

11 A Brief History of the Micrometer Creating the Basic Design of a Micrometer

Micrometers for All Applications

Micrometer Caliper Introduced by Victor Machine Co.

rown and Sharpe correctly It appeared that both Brown and Bsurmised that micrometers would Sharpe and Victor Machine had developed be a necessity in all machine shops. In micrometers almost simultaneously. At this 1877, nearly 10 years after their tiny period in America, the sewing machine pocket-type micrometers debuted, was soon to become a popular product. Brown and Sharpe produced their first To manufacture parts and components 11inch outside micrometers (accurate for sewing machines more precisely, the to 0.001inch or 0.0254mm). It took micrometer was a must. them a long time to reach this point. Regardless of which company was The inaugural issue of American the first to introduce it to the market, Machinists in November 1877 carried both companies ensured that they were an advertisement placed by Victor widely available. Micrometers were Machine Co., announcing a new used in machine shops to ensure it raise micrometer made in America. There product quality. It was the efforts of these was no advertisement placed by Brown companies to mass-produce and promote and Sharpe. micrometers that deserves recognition.

A Brief History of the Micrometer 12 A Brief History of the Micrometer

Chapter III: The Rise of Industry

Expanding Technologies in Japan

Textile factory in the 1910s (Source: Gunze)

n Japan, the aspiration to become a creating prototypes. With this support, I"nation of power and technology" domestic manufacturers in Japan were emerged during the Meiji period. This ready to produce products themselves. spirit was further enforced during the Such companies started by taking Taisho and Showa periods that followed. foreign-made products and creating their Consistent with this direction, the equivalents domestically. In the process, Japanese government also helped bring they acquired technical know-how and advanced foreign technologies into created production techniques suitable Japan, supporting the growth of its do- for their own situation. mestic industries. The Army, Navy and At the time, the domestic industry Air Force, together with the Railroad was dominated by textile production. Ministry also pushed industrialisation in The production of air planes and cars for Japan. military use only just started. The con- With this as a backdrop, a move sumption of tools increased in tandem to create domestic companies dealing with the push for industrialisation. in advanced industries such as machine After the Manchurian Incident, tools and measuring instruments the production of air planes accelerated started. To help in this process, gov- which in turn boosted the need ernment organisations helped import for machine tools and measuring products from overseas and assisted in instruments of all kinds.

13 A Brief History of the Micrometer Progress in Japan

Domestic Manufacturers Start R & D

Model of Early Mitutoyo factory in Kamata, Tokyo

he first use of a micrometer in the first started in Japan. Tfactory in Japan was at the end of According to the official record, the Meiji period. At the time, it was Sonoike Manufacturing Co., then limited to a handful of companies. the best known machine tools and With the use of micrometers, they fixture maker, made a prototype were able to measure products more micrometer in 1918. They made it accurately and quickly. As a result, based on C. E. Johansson's model. In there was a significant drop in rejected 1921, Sonoike Mfg. Co. participated products. in a machine tool show organised Imported micrometers were by the government, displaying inch limited in number. Some companies and metric micrometers as well as tried to make micrometers micrometer heads. themselves. The first attempt was Shortly after 1929, Tsugami not recorded and there is no way Mfg. Co. and from 1931 through to tell whether it was a private 1934, Mitutoyo, Mitsuiseiki, NSK, or military organisation. It is also Fujikochi, started R&D work on impossible to tell when this move micrometers.

A Brief History of the Micrometer 14 A Brief History of the Micrometer

Micrometers by Mitutoyo

First Mitutoyo Micrometer

Promotional towel distributed nationwide

itutoyo was among the group World's Best Micrometer". Mof manufacturers that started The leading principles of his to work on micrometers in the early company were "Good Environment, period. Its founder, Yehan Numata, Good People, and Good Technology". purchased a small lot in Kamata, Tokyo, Having led his small group, he under- in 1934. He started his R&D efforts, stood the importance of the mindset of hoping to introduce his micrometers his coworkers. Yehan Numata believed one day. Three years later, after count- that good people could be raised in a less trial-and-error, he finally produced good working environment. the first Mitutoyo micrometer for sale. In order to manufacture products Their first commercially available trusted by users, he knew that the micrometer was produced in 1937. To process of educating his coworkers was promote the first lot of micrometers, essential. A concept of raising good a special promotional towel was people first before making products prepared. On it was a slogan: "Good, is not new today. This approach at Inexpensive and Long Lasting: The Mitutoyo started over 70 years ago.

15 A Brief History of the Micrometer Chapter III: The Rise of Industry

Progress in Japan

Micrometers During the War

Battleship Yamato under construction (Source: Yamato Museum)

icrometers made in Japan became with the Yamato, the largest battleship Mavailable from several sources. ever built. Comprehensive planning However, not many of them received the was needed to produce a battleship level of trust they had expected. It was as large as the Yamato in a narrow difficult to manufacture micrometers shipyard, and make it seaworthy by the without prior experience. It was equally set deadline. Necessary components, difficult to have them accepted by users often extremely large, must be delivered who preferred imported brands. to the specified location on the Meanwhile, the nation started specified day to make the best use of to prepare for war in 1941. Demand a limited-space dry dock. To overcome for micrometers increased along with this enormous task of building the increased production of war materials largest battleship, it was necessary to such as guns, battleships and air planes. standardise components and parts. As As imported goods were restricted, a result, the "Just-In-Time" method the military government authorised was formulated out of necessity. Mitutoyo to continue the production The road to standardisation of micrometers. This production was started here, and years later this process carried out until the end of the war. was adopted in production and quality This is not well known, but control. In short, the Battleship Yamato the first serious attempt to manage was the roots of modern production production processes in Japan started methods in Japan.

A Brief History of the Micrometer 16 A Brief History of the Micrometer

Chapter IV: Rise of "Made in Japan"

Hardships During and After the War

Private citizens supporting the war efforts

hroughout the WWII period and Skilled engineers and workers had Teven thereafter, the production of gone to the battlefields, leaving micrometers encountered enormous behind the young, the old, and the difficulties. A nation engaged in war womenfolk. required micrometers to produce high Then came the end of WWII. All accuracy and high quality war materials major cities had been burned to ashes, such as tanks, battleships, air planes, and Mitutoyo's Kamata Factory was no guns and ammunition. However, exception. The adjacent Mizonokuchi micrometers were in short supply. Factory ceased to operate and closed Meanwhile, so called ABCD-line its doors. With only a few security allies stopped all shipments of essential personnel to guard the property, the raw materials. This aggravated an entire operation was closed. already short supply of raw materials Later, soldiers from overseas for the metalworking industry. To returned to their homeland. The produce a less than perfect product nation awoke to a different world, and or to create waste was not tolerated. slowly started to rebuild itself.

17 A Brief History of the Micrometer Period of Worldwide Expansion

From Reconstruction to Mass Production

Convyor-belt line during the 1960s

econstruction of a nation had By the 1950s, domestic demand Rbegun. But basic items such as for consumer goods such as televisions food, clothing, and living necessities and cars had increased and gave had to be provided for first. It took a momentum to the manufacturing while for measuring gauges to make a sector. Against this backdrop, mass comeback. Nevertheless, in October production had started, and in the 1947, Mitutoyo restarted production process stimulated the economy in of micrometers and in 1949 it was Japan. To achieve the goals of a large ready for full production. scale production, all parts must be In the international scene, made within much tighter tolerances. polarisation of two major powers Statistical Process Control to manage was established and war broke out production runs and rational in the Korean Peninsula. The US approaches in manufacturing took the military personnel stationed in Japan centre stage during this period. moved quickly to Korea. In so doing, A trend toward tighter size control they turned to Japan for military was not limited to mass-produced materials, thus igniting a round of parts. In shipbuilding and in steel mills, economic activities which revived the micrometers were also used to validate metalworking industry. specifications.

A Brief History of the Micrometer 18 A Brief History of the Micrometer

Innovations to Meet the Needs

Extra large micrometer for heavy industry

s the manufacturing sector in Japan 1: Satin-chrome finished thimble, Aregained its strength, the areas sleeve, and frame: Improved contrast of application where a micrometer of graduated lines and assured longer could be used increased steadily. The tool life. 2: Friction Thimble: In addition to the measuring range of micrometers also standard ratchet stop, this feature was increased significantly. For example, added to provide constant pressure, in 1953 a micrometer capable of making it easy for an operator to use measuring a 3 meter diameter was it with one hand. produced and sent to a shipbuilder to 3: Hardened and ground spindle threads to measure a shaft. achieve higher accuracy and durability. By taking into account user 4: Carbide-tipped measuring faces for feedback on micrometer specifications, more precision and durability. the quality of Made-in-Japan 5: The conventional ring clamp was redesigned to a lever-type spindle micrometers reached a point where clamp. they were acceptable to overseas 6: Special-purpose micrometers for threads customers. and other forms were produced. Some of the improvements made 7: Mechanical type digital counter was were: added to standard micrometers.

19 A Brief History of the Micrometer Period of Worldwide Expansion

Maturity Through Intense Competition

Micrometer bearing "Made in Japan"

uring the war period and a few surpass them in quality and price. All Dyears thereafter, the quality of "less told, “Made in Japan” products started than perfect" micrometers started to to be accepted by customers in many improve dramatically due in part to the countries, and the micrometer was no rising demands of end-users. Research exception. Behind all this was a series and development had also begun to of improvements that took place in discover materials that would not be areas such as materials, manufacturing affected significantly by variations in methods, assembly, and process control. temperature. Another area of research Surviving through intense competition, during this period was to find a new Mitutoyo established itself as a leader in way to cut spindle threads - the heart high-tech micrometers. of the micrometer. Innovations in electronics changed The quality improvement of the way all measuring instruments micrometers was one thing, but were perceived: The emphasis had containing manufacturing costs was shifted from reading graduated lines to another. In spite of that, Mitutoyo's mi- glancing at LCD displays. The advent crometers gradually became comparable of electronics gave rise to a new breed to foreign counterparts and started to of micrometers.

A Brief History of the Micrometer 20 A Brief History of the Micrometer

Chapter V : A Partner of Information System

From Reading Graduations to Looking at a Display

Digital Micrometers (mechanical and electronic models)

he bulky table-top micrometers It became necessary for standard Tof the past had been completely micrometers to be redesigned to transformed into a much simpler and show measured dimensions in digits easier gauge to handle on the shop floor. ­— a move from reading graduations to A revised micrometer frame allowed looking at LCD display. it to reach areas once inaccessible by Earliest models were based on old models. Not long ago, machinists mechanical digital counters. Those needed to take time to carefully were capable of resolutions up read and interpret line graduations. to 1/100mm. With the advent of Everyone understood that one must pay LED/LCD, 7-segments, and other attention in the reading process. If a innovations, micrometers were given micrometer was used only a few times a chance to incorporate what the a day, it would not matter; but if the latest in microchip technology offered. reading should be repeated tens and Thus, Digital Micrometers based on hundreds of times a day, the process of electronics became a standard. reading micrometers became very time It opened up a potential area where consuming. Moreover, operator fatigue micrometers might still be improved in would cause reading errors. view of a total measurement system.

21 A Brief History of the Micrometer Moving into the Silicon Age

Advancements in Digital Displays

eading a micrometer is a delicate Roperation: machinists are trained Introducing Count Micrometers to add one revolution to a micrometer reading depending on how many turns still produced because many seasoned the thimble has turned. For example, machinists didn’t need the digital a thimble reading may suggest either counter. They were also not satisfied 8.23mm or 8.73mm. This decision with the limitation of an accuracy of must be made by looking at the sleeve only 1/100mm. They demanded a more intently — a process of learning finer digital resolution of 1/1000mm how to read a micrometer. (1µm). The birth of microchips and The introduction of the digital LSIs has also changed the industry, and micrometer eliminated this possible demand steadily increased for these reading error, and became the higher accuracy micrometers. preferred system for all users the The first LCD digital model with world over. The advertisement above a resolution of 1/1000mm offered by introduces a new model called the Mitutoyo required three batteries and "Count Micrometer". This feature was rather heavy. One noteworthy was added to all models to make feature on this early model was a plug- readings fast and accurate. However, in connector to send data to other the classic line graduated models were devices.

A Brief History of the Micrometer 22 A Brief History of the Micrometer

Merits of Data Output

Overview of a Quality Control System (in 1987)

C Machines and automation tions for a gauge has also changed Nin the field of machine tools from a simple hand-held micrometer to revolutionised the traditional method an input device for a total information of production. In larger factories, total system. control systems were deployed through In the manufacturing sector, the computer technology where data is ultimate goal of information technology stored and shared by many users. This is to build a climate of shared data required a flexible system of control to throughout the entire organisation. cope with a wide variety of products With this in mind, Mitutoyo's digital produced in small lots. micrometers feature an output port for In this day and age where downloading so that creating SPC and dimensional tolerances are much other reports are easily done. tighter and the products manufactured This approach leads to the are more complex, quality control prediction of controlled dimensions and production methods must and avoidance of potential hazards also be evolved from a single point in quality control. With this line of of measurement to multi-faceted thought, Mitutoyo is at the cutting operations. In so doing, the expecta- edge of technology.

23 A Brief History of the Micrometer Moving into the Silicon Age

Completing a Full Circle

Ads for Digimatic products

arge and medium size companies product cannot achieve the status of L aim for consolidation of all data the "very best" in its intended field in plant operations, from materials without accommodating requests to quality control, and from initial raised from all levels of users. In the design stage to the final product. process of product planning, engineers Not all manufacturing operations must look at the market through a lens are alike in the pursuit of their goals. resembling a compound eye. The majority of medium-to-small From the outset, only a handful companies in Japan do not need such of companies started making a comprehensive system in quality micrometers, and were joined by control. nearly a dozen more in Japan. Some users pay more attention Emerging from this, the winner was on how to maximise the value of a Mitutoyo, which has been producing single micrometer. Those who are micrometers for over seventy years. It in this group demand compactness, produces literally hundreds of types long-lasting battery life, waterproofing of micrometers for every conceivable and low cost; all of which are purpose. Behind all this is a spirit of reasonable and realistic requests. A putting the users' needs first.

A Brief History of the Micrometer 24 A Brief History of the Micrometer

Chapter VI: The Future of Micrometers

A Revolutionary Advancement in Micrometer Technology

Range: 0~25mm Resolution: 0.001mm

Range: 25~50mm Resolution: 0.001mm

brief history of the micrometer has available. However, the thimble would A been presented in the preceding also need to accommodate 100 lines chapters. For all micrometers, the on its circumference, which would core element of magnification are the result in a far larger thimble. This screw threads that transformed minute would negatively affect one handed linear displacements into a larger operation of a micrometer. To keep areas represented by the thimble. The it within a reasonable size, space accuracy of the threads dictated the between the graduation lines must be accuracy of a micrometer. made narrower, even though it may be Since the early days, micrometers harder to read. employed 0.5mm pitch threads The new Mitutoyo QuantuMike (.025in. for inch models), which took introduced in 2007 is based on a 2mm 50 revolutions to travel from 0 to thread pitch — moving four times 25mm. Proportionally, it would move faster than the conventional designs. twice as fast if a 1mm thread pitch This unique configuration has never was used. Such micrometers are also been attempted before.

25 A Revolutionary Advancement in micrometer technology itutoyo unleashes the next Mgeneration of micrometers, delivering unsurpassed performance since the innovation by James Watt in 1772. Thanks to the integration of sophisticated manufacturing and cutting-edge technology from Mitutoyo, the QuantuMike far exceeds users’ expectations. The name QuantuMike is derived from ‘Quantum’ and ‘Micrometer’, reflecting our belief that this tool represents a quantum leap in micrometer ergonomics.

A Brief History of the Micrometer 26 A Brief History of the Micrometer

Pioneering Design: 2mm Feed Per Revolution

Measuring coaxial workpiece

ll conventional micrometers Another significant technological Arequire 50 revolutions per 25mm. feature of the QuantuMike is its With 2mm screw threads, the new high-resolution. Conventional digital QuantuMike moves four times faster, micrometers based on 0.5mm pitch thus making it much easier to operate. threads subdivide one revolution of the spindle into 500 equal parts, thus A little known fact: after a square reading to 0.001mm (1µm) resolution. workpiece is measured, the spindle To provide the same reading for the must be rolled back to disengage it. four-times-faster QuantuMike, one spin- A short twist backward on the new dle rotation must be divided into 2000 QuantuMike will allow this step to be equal parts. For this reason, Mitutoyo completed quicker. The secret is in the developed a new disc encoder technol- unique, patented 2mm pitch threads ogy and is the first to achieve this goal. design — another first by Mitutoyo. The QuantuMike is also enhanced

27 The Next Generation of Micrometers

Ratchet Ratchet on thimble on speeder

Ratchet-induced microvibrations Proven waterproof ensure repeatable measurements

シンブ ル部 スピーダ 部 ラチェ ッ ト ラチェ ッ ト

with the following features: different dimensions. Repeatable measurement Function lock helps prevent error The patented ratchet thimble QuantuMike is equipped with a function mechanism helps ensure repeatable lock feature to prevent the origin results by transmitting microvibrations point being moved by mistake during along the spindle to the contact face measurement. to provide a constant measuring force Dust/water resistance with IP65 and encourage good contact with the protection level workpiece. The ratchet works from Excellent resistance against oil, water the thimble as well as the speeder so and dust enables this product to be used it is always easy to use - even when in machining situations that include making measurements one-handed. splashing of coolant fluid. The sound of the ratchet provides the The new QuantuMike is a break- user with a sense of confidence and through in the history of micrometers. the speeder enables the rapid spindle This is what all future micrometers feed needed when measuring widely should be.

A Brief History of the Micrometer 28 A Brief History of the Micrometer

Index

A L American Machinists 13 Lord Chancellor 8 B M B&S Pocket-type Micrometer 12 Machine Tools 2, 3 Bridgeport Brass Plate Co. 12 History 4 Brown and Sharpe 10, 11, 12, 13 Mass Production 19 Maudslay, H. 8 C Micrometer Caliper Micrometer 6 “U”-shaped frame 7, 10 Count Micrometer 23 3 Meter Diameter 20 Dust/water Resistance 29 D Function Lock 29 High-Resolution 28 Digital Micrometers 22 History 4 Japan 15 F LCD display 22 Father of Machine Tools 8 Made in Japan 20, 21 Mechanical Digital Counters 22 G Modern 10 One Handed Operation 10 Gascoigne, W. 6 Plug-in Connector 23 J Reading Error 23 Repeatable Measurement 29 Japan Micrometer Caliper 13 First Micrometer 15 Millionth of an Inch Measuring Foreign Technologies 14 Machine 9 Industrialisation 14 Mitutoyo World War II 17 First Micrometer 16 Johansson, C. E. 15 Leading Principles 16 Just-In-Time method 17 QuantuMike. See QuantuMike

29 A Brief History of the Micrometer N T NC Machines 24 Tsugami Manufacturing Co. 15 Numata, Y. 16 V P Victor Machine 13 Palmer’s Micrometer 10 Palmer, J. 10 W Q Watt’s Tabletop Micrometer 7 Watt, J. 7 Quality Control System 24 Whitworth, J. 9 QuantuMike 26, 27, 28 Wilmot, S. 12 Features 29 World War II 17, 18 S Y Screw Threads 26 Yamato, Battleship 17 Magnification 7 Principle 6 Sonoike Manufacturing Co. 15 Statistical Process Control 19 System Palmer 10, 11

A Brief History of the Micrometer 30 Mitutoyo Corporation 20-1, Sakado 1-Chome, Takatsu-ku, Kawasaki-shi, Kanagawa 213-8533, Japan T +81 (0) 44 813-8230, F +81 (0) 44 813-8231 http://www.mitutoyo.co.jp 29.50 0811 1 Ja-(PA) FP, Printed in Japan