Before the vertical machining center is processed, the user must measure the length and diameter of the tool on the spindle and its diameter and other compensation parameters. At present, the commonly used methods for measuring the compensation parameters are: Test cutting, electronic probe, mechanical and optical tool. The test cutting method has been rarely used, the electronic head is expensive, the tool instrument is used outside the machine, and the application is wide. Both the electronic head or the knife instrument are used in the static condition. In actual cutting, the actual result of the machining is not exactly the same as the static tool data because of the influence of the cutting force and vibration. When the tool quality is reliable and the machining process is stable, the axial and radial are 0. 01mm-0. The correction of 02mm. According to the specific conditions of the vertical machining center and the tool system, the operator should adjust it by experience.
1. Before machining, the cutting force is roughly estimated according to the machining center, cutting amount, cutting tool and workpiece material, and some existing empirical formulas are used.
2. Loosening the nut to allow the spring to bear only the weight of the measuring rod. According to the cutting force, the spring stiffness, the tightening nut, and the compression spring. The spring force is basically equal to the cutting force.
3. Install the measuring device according to the diagram and put it on the worktable. Dial 6 hit on the 7 block (or a few blocks overlap) top, the indicator is set to "0", a reference measurement.
4 micrometer, playing on the surface of the measuring rod 3. Drop the spindle 5, make the tool 4 contact the upper surface of the measuring rod, and continue to compress the spring 2 to make it deform and write down the readings. At this point, the nut 9 and the gasket 8 should be disconnected from the measuring seat 1, and the cutter bears the spring elastic force that is basically the same as the cutting force. The deformation of the dial gauge readings show or ignored, be considered, depending on the situation.
5, remove the dial, rose back to the origin of the tool.
6, tool overhang length = machining center Z axis travel - at the Z axis value of gauge block length - dial gauge reading
Without considering the error of machining center measuring device, without considering the manufacturing error of Machining Center Taiwan and wear, with a comparison method of measurement, gauge, micrometer, limit error of measurement is 0. 03mm.
In the process of processing, the cutting force varies greatly, and it can be weighted averagely according to the effect of different cutting forces on the cutting. When carrying out important surface machining, if the cutting force is quite different, each cutting force can also be operated by corresponding tool. All the results are input into CNC system, and the specific compensation parameters are invoked respectively when cutting.
The tool instrument should be designed according to the specifications of the machining center, the tool, the workpiece and the cutting amount. Both ends of the spring are tightened and the stiffness should be appropriate. The required elastic force should be produced and the elastic force should be within the scope of its work. Before and after the tool contact measuring rod surface, it should be 0. 01mm is slow feed for units. In order to ensure the relative motion of the sleeve and the measuring rod, the H6 / H5 gap coordination can be used. When the tool compression spring is used, it may cause the deflection of the measuring seat and the two axis of the measuring rod, which leads to the tilt of the surface of the measuring rod and increases the measurement error. The surface of the measuring rod can be fine grinding to reach the level of 3-4. When measuring, the measuring rod on the surface of the outer ring dial in a circle, take the average of the minimum and maximum value of the dial indicator readings.
