Joseph Rogers BrownBorn 26 Jan 1810; died 23 Jul 1876 at age 66.American inventor and manufacturer who made numerous advances in the field of fine measurement and machine-tool production. He perfected and produced a highly accurate linear dividing engine in 1850, and in the succeeding two years he developed a vernier caliper reading to thousandths of an inch and also applied vernier methods to the protractor. Brown's micrometer caliper, widely used in industry, appeared in 1867. He also invented a precision gear cutter in 1855 to produce clock gears, a universal milling machine in 1862, and, perhaps his finest innovation, a universal grinding machine (patented in 1877), in which articles were hardened first and then ground, thereby increasing accuracy and eliminating waste. Cofounded J.R. Brown & Sharpe in 1853.[Image: Brown's universal milling machine] |
