The spiral micrometer, also known as micrometer, spiral micrometer, and centimeter card, is a more precise measuring tool than the vernier caliper. It can be used to measure the length to 0.01mm and the measuring range is several centimeters. A part of it is machined into a thread having a pitch of 0.5 mm. When it is rotated in the sleeve of the fixed sleeve B, it will advance or retreat, the movable sleeve C and the screw are integrally connected, and the periphery thereof is equally divided into 50 divisions. The number of full turns of the screw is measured by a scribe line spaced 0.5 mm apart on the fixed sleeve. The less than one turn is measured by the scribe line around the movable sleeve. The final measurement requires an estimate of one decimal.
The first such measurement tool was patented in 1848 by the French inventor Jean Laurent Palmer, known as the "thread caliper with a circular ruler frame". Today, we still use this typical feature to make an outer diameter micrometer. The introduction of the micrometer into the mechanical world began with the visit of two American engineers Joseph R. Brown and Lucian Sharpe to the Paris exhibition in 1867. Their attention was drawn to Palmer's invention and was of great interest. After the design of Palmer was improved, the products were mass-produced and successfully promoted by the two partners in the market. When Swiss TESA decided to manufacture the outer diameter micrometer, they repeated the story of the past and made the product the company's first product. Except in a few cases (such as measuring the micrometer of a gear), the micrometer we use follows the Abbe principle (Abbe principle), just like a comparator. The micrometer mandrel is machined by a modern grinding machine. The contour of the thread is highly accurate, the pitch deviation is negligible, and the machining conditions guarantee extremely low measurement uncertainty of the micrometer.
The spiral micrometer, also known as micrometer, spiral micrometer, and centimeter card, is a more precise measuring tool than the vernier caliper. It can be used to measure the length to 0.01mm and the measuring range is several centimeters. A part of it is machined into a thread having a pitch of 0.5 mm. When it is rotated in the sleeve of the fixed sleeve B, it will advance or retreat, the movable sleeve C and the screw are integrally connected, and the periphery thereof is equally divided into 50 divisions. The number of full turns of the screw is measured by a scribe line spaced 0.5 mm apart on the fixed sleeve. The less than one turn is measured by the scribe line around the movable sleeve. The final measurement requires an estimate of one decimal.
The first such measurement tool was patented in 1848 by the French inventor Jean Laurent Palmer, known as the "thread caliper with a circular ruler frame". Today, we still use this typical feature to make an outer diameter micrometer. The introduction of the micrometer into the mechanical world began with the visit of two American engineers Joseph R. Brown and Lucian Sharpe to the Paris exhibition in 1867. Their attention was drawn to Palmer's invention and was of great interest. After the design of Palmer was improved, the products were mass-produced and successfully promoted by the two partners in the market. When Swiss TESA decided to manufacture the outer diameter micrometer, they repeated the story of the past and made the product the company's first product. Except in a few cases (such as measuring the micrometer of a gear), the micrometer we use follows the Abbe principle (Abbe principle), just like a comparator. The micrometer mandrel is machined by a modern grinding machine. The contour of the thread is highly accurate, the pitch deviation is negligible, and the machining conditions guarantee extremely low measurement uncertainty of the micrometer.
