Roundness dimension measuring instrument  

     The principle of the roundness meter is the same as that of the three coordinate measuring machine. In fact, its working principle is very simple. The three coordinate measuring machine is a point acquisition tool. Its principle is to first acquire points, then form a line from points, and then form a three-dimensional model from lines. CMM is a kind of measuring equipment with guiding mechanism, length measuring element and digital display device in three mutually perpendicular directions, a workbench (not necessarily large or giant) that can place workpieces, the measuring head can be moved to the measured point quickly and manually or mechanically, and the coordinate value of the measured point is displayed by the data reading equipment and digital display device. Obviously, this is the simplest and most primitive measuring machine. With this measuring machine, the coordinate value of any point in the measuring volume can be displayed through a reading device a…