Application of machine tool probe and tool setter in on-line measurment of NC machine tools(2/4)

By Wangmingjia Qidu Metrology Technology

Two. Application of probe in machining process
1)The application of batch parts machining process – automatic centralization, automatic alignment, automatic compensation
The domestic application of in-machine measurement is some mobile phone metal parts processing companies dominated by Foxconn. Many contract manufacturers of apple, mainly Foxconn, encountered serious problems in processing quality and efficiency when processing the middle frame and back frame of mobile phones. In fact, it is product alignment and centering. According to the traditional method, the method of alignment of multiple products in one fixture on the machine tool is very slow, and the accuracy is controlled by operators and difficult to control. If centering is involved, the program has to be interrupted and re-started after calibration and compensation. When the dimensional accuracy is required to be 0.05mm, the scrap rate of batch processing of mobile phone middle frame reaches 50%, and the efficiency is only 1 person with 2 machines. In order to solve the problems of high scrap and low efficiency, Foxconn has introduced probe. Through the functions of automatic alignment, automatic centering and automatic compensation of the probe, the scrap rate is directly reduced to less than 1%, the processing process program is not interrupted, and the personnel efficiency is improved to 8 machines with one person. At present, probes are widely used in batch parts processing, including mobile phone middle frame, back frame and other parts processing, watch parts processing, ordinary cylinder processing, engine cylinder processing, aluminum hub processing and so on.


2)Application of machining process for small batch products such as molds — post-machining measurement
For traditional mold machining reloading and realignment of workpiece is a difficult problem. After finishing the machining, technician need to disassemble the workpiece and check them on CMM. If there are unqualified dimensions, it is difficult to rework and the quality of rework is not good, because it cannot be re-aligned. The on-machine measurement can solve this problem perfectly. The key dimensions shall be measured on-machine before disembarking, and the unqualified dimensions shall be reworked before off the machine. This is the industry commonly known as the inspection after machining.
Mold testing often involves curved surfaces, which is called 3D measurement, in which the algorithm is very complex, can only be achieved by professional measurement software. In summary, software is as important to product quality for 3D measurement as operating software is for CMM. For on-machine measurement software introduction, please refer to section 4.


3)Application of on-machine probe for NC lathe machining – outer circle, inner circle, end dimension measurement
At present, there are few on-machine measurement applications of probe in NC lather machining, One of the reasons is limited by the traditional cutting-tools row and the number of 4-position cutting-tool tower; That is to say, the cutting-tool position is not enough, and it will be more tense after installing the probe to occupy the cutting-tool position. In recent 5 years, with the popularization and application of multi – position rotary cutter tower, the application of probe in NC lathe is increasing obviously. On – machine measurement in lathe is more in cooperation with automatic lathe processing production line use, by monitoring the inner, outer circle and end face size to do the tool breaking detection and automatic compensation of tool wear. The characteristic of the lathe probe is that the shape should be common with the cutter and easy to clamp. The probe adopts radio transmission technology.


Post time: Nov-27-2021