The error of checking the roundness in the processing of precision parts can be used to use the roundness method and two points and three points. The method of the roundness instrument is to place the measured workpiece on the circular workbench, find a positive rotating axis, and contact the roundaber head to contact the outer circle of the workpiece and turn around. The measurement results are finally displayed through sensors, amplifiers, filters, and computing circuits.
If the output is the graphic of the actual contour, you can use the concentric circular template set, and use the difference in the radius of the two tolerance and concentric circles as the circular error of a certain section. round
The degree instrument is suitable for parts with higher measurement accuracy.
When the shape of the two -point and three -point method When the shape of the contour is round, the two -point method can be measured by two points. Use the measuring instrument and other measuring instruments such as a caliper, thousands of feet, microtometer, etc., and measure the maximum difference in the diameter of the measuring diameter along the regular interceptance.
Because the maximum and smallest diameter circles are not necessarily concentric, this method is just a similar measurement.
When the measured contour is round, the two points cannot be measured by two points. At this time, the three -point method can be measured. Use the V -rack support to be measured by the measurement of the workpiece, and use the indicator to measure the maximum difference between the workpiece rotation for a week, and take it as the circular error of the cross -section. The commonly used V -rack angle α has 60 °, 72 °, 90 °, 108 °, and 120 °, etc. The three points in the processing of precision parts can also be used for high precision measurement.
