In such a high speed and construction situation, once the operator can not press the emergency stop button due to programming and operation errors, the tool has collided with the workpiece. Computer Gong processing | Dongguan high-speed computer gong processing | Dongguan die processing | Dongguan machine parts processing | CNC processing in order to prevent the emergence of machine tools and personal affairs, the following methods can be adopted in programming and operation (take FANUC system as an example).
The origin of the workpiece coordinate system set by the programmer should be outside the workpiece blank, at least on the workpiece surface.
Under normal conditions, the origin of workpiece coordinate system can be set anywhere, as long as the origin has a certain connection with the origin of machine tool coordinate system. But in practice, if the instruction value is zero or close to zero, the tool will point directly to zero or near zero. In milling, the tool will run to the worktable of machine tool or the base of fixture: in turning, it will run to the base of chuck. In this way, the tool will penetrate the workpiece and point directly to the datum. At this moment, if we want to move quickly, something will happen.
FANUC system generally set: when the decimal point is omitted, it is the smallest input unit, usually micron. When the decimal point is omitted, the input value will be reduced to one thousandth. At this moment, the input value will be close to zero. Perhaps, because of other factors, the tool should have been separated from the workpiece, but the practice has not been separated from the workpiece and entered the workpiece. When this happens, the zero of the workpiece coordinate system should be located outside the workpiece or on the base of the workbench (or fixture), and the results will be different.
Programmers and operators should be more careful about decimal points when writing programs.
FANUC system is the smallest setting unit when decimal point is omitted, while most domestic systems and some systems in Europe and America are mm when decimal point is omitted, that is, calculator input method. If you get used to the calculator input method, there will be problems in the FANUC system. Many programmers and operators may use both systems. In order to prevent the scale from becoming smaller due to decimal points, decimal points should be added to the program of calculator input method. Computer Gong processing | Dongguan high-speed computer gong processing | Dongguan die processing | Dongguan mechanical parts processing | CNC processing, to do so, for a certain type of system is surplus, but after cultivating habits, there will be no problems due to decimal points.
In order to make decimal points attractive, isolated decimal points are usually written as “.0” in programming. Of course, the zero after the decimal point of the numerical value is neglected in the execution of the system.
When adjusting the workpiece coordinate system, the operator should set the reference point outside the physical (geometric) length of all the cutters, at least on the cutter location of the longest cutter.
For the workpiece coordinate system on the workpiece installation drawing, the operator acquires it by setting the offset of the machine tool coordinate system on the CNC machining center. That is to say, the operator sets a reference point on the CNC machining center, and finds the scale between the reference point and the zero of the workpiece coordinate system set by the programmer, and sets this scale as the workpiece coordinate system offset.
On the lathe, the reference point can be set on the rotating base of the tool holder, on the tool tip of the reference tool or in other directions. If no additional motion is added, the zero of the programmer’s instruction is to move the reference point of the tool holder (CNC machining center) to the zero azimuth of the offset. At this moment, if the datum point is set on the rotary base of the tool holder, the tool holder will collide with the workpiece. In order to ensure no collision, the reference point of CNC machining center should be located not only outside the tool holder, but also outside all the tools. So even if the tool holder is equipped with a tool, the reference point will not collide with the workpiece.
In CNC machining center, the reference points of X and Y axes are on the axis center line. However, the reference point of Z axis can be set at the end of the spindle or at some point outside the end of the spindle. If the instruction is zero at the spindle end, the spindle end will reach the zero orientation specified in the coordinate system. Computer Gong processing | Dongguan high-speed computer gong processing | Dongguan die processing | Dongguan mechanical parts processing | CNC processing at this moment, the end of the spindle key will collide with the workpiece: if the spindle is equipped with a tool, it will collide with the workpiece. In order to ensure no collision, the reference point on Z axis should be set outside all tool lengths. Even without additional motion, the reference point will not hit the workpiece.
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