How to calibrate the accuracy of linear modules?

The accuracy of the linear module generally refers to the repeated positioning accuracy and guiding accuracy, the repeated positioning accuracy is the accuracy of the linear module in the reciprocating motion 7 times the dial meter or laser interferometer detection,the linear module reaches positive or negative 0.02 to 0.01mm,generally belongs to the high precision level.The guiding accuracy refers to the most basic performance indicators of linear guide rail,moving parts along the guide rail,regardless of load, should ensure the straightness of the moving track and the accuracy of positioning, which is to ensure the good operation of the machine tool key.

Generally speaking,all kinds of equipment have provisions or standards for the flatness,verticality and equidistance requirements of the guide rail pair itself.The accuracy calibration of the linear module is mainly carried out from the following four aspects:

●Positioning accuracy:with a larger stroke as the reference length, expressed by the absolute value of the greater error between the actual distance moved from the reference position and the command value;

●Repeated positioning accuracy: any point is repeatedly positioned 7 times in the same direction,and then its stop position is measured, and 1/2 of the greater difference in the reading of the watch head is calculated.As a test principle,the test is carried out at the center of the moving distance and at roughly both ends. The greater value of the test value is taken as the measured value,expressed by 1/2 of the greater difference with ±;

●Clearance: feed the inner slider, based on the reading of the test indicator when the slider has just started to move,from this state,independent of the feed device, apply the load in the same direction as the inner slider movement(feed direction of the table),and then take the difference between the reference value at the start of the test and the position at the return as the measured value. The test was carried out at the center of the moving part and at roughly both ends, and the greater value of the obtained value was taken as the measured value;

●Running parallelism:a standard ruler is placed on the platform where the linear module is installed,and the test indicator is used to test within the range that the inner slider can move.The greater difference in reading within the moving range is the measured value.

Linear Modules from China, Linear Modules Manufacturer & Supplier - ALM (autolinearmotion.com)