Outside diameter micrometer

Spiral micrometer gauge 0.01 mm outside diameter micrometer 0 to 25 mm experiment instrument physical instrument
micrometer

(1) the usage and structure Spiral micrometer (also called micrometer) is more precise than the vernier calipers measure the length of the tool, use it to measure the length can be accurate to 0.01 mm, measuring range to a few centimeters. Structure of spiral micrometer as shown. Little anvil of spiral micrometer scale of fixed and fixed on the frame, knob, fine-tuning knob movable scale, micrometer screw together, through the precision screw set on the fixed scale.

2) the principle and use Spiral micrometer is made based on the principle of spiral magnification, the screw rotates in the nut, screw and switch back and forth along the rotation axis of a pitch distance. Therefore, tiny distance along the axis direction, can use the reading on the circumference of a circle. Spiral micrometer precision thread pitch is 0.5 mm, movable scale has 50 equal scale, movable scale revolving, micrometer screw can be forward or backward, 0.5 mm, so the rotate each small degree, equivalent to a micrometer screw forward or backward the 0.5/50 = 0.01 mm. Visible, each small movable scale degrees according to 0.01 mm, so in spiral micrometer can be accurate to 0.01 mm. Because can estimate again read a, can read mm micrometer level, so it is also a micrometer. Measurement, when the small anvil and micrometer screw together, movable dial zero if coincided with the fixed scale zero overlap, spiral micrometer screw, and make small abundant and micrometer screw surface contact length under test two