Domestic CNC system replaces imported CNC system for CNC lathe transformation

The domestic CNC system replaces the imported CNC system to transform the CNC lathe. Liuzhou Vocational and Technical College Guangxi Liuzhou Fangsheng Accessories Co., Ltd. purchased a second-hand CNC lathe produced in the early 1990s. The machine is equipped with an OTE lathe produced by FANUC of Japan. CNC system. Due to the aging of electrical components, the numerical control system is overloaded and stopped. Considering that the machine tool is used for a long time, the mechanical part has a certain degree of wear, and the geometric accuracy is difficult to recover. If the foreign CNC system is used for transformation, the processing accuracy will not be obviously improved, and the company will be tightly funded, weigh the pros and cons, and decide to adopt the domestic The CNC system was transformed.

Imported system configuration domestic system configuration Japan FNALCOTE type CNC system Guangzhou GSK980TA CNC system X axis 12Nm servo motor, X axis 15Nm servo motor, with brake Z axis 12Nm servo motor Z axis 15Nm servo motor 11kW; servo spindle motor 11kW / variable frequency spindle motor CNC The quality of the X and Z axis installation and commissioning of the lathe directly affects the machining accuracy of the machine tool. Therefore, on the basis of increasing the torque of the servo motor of the feed axis, the servo parameters and motor parameters are optimized, and the backlash of the machine tool is re-detected and compensated. After use, it can fully meet the precision requirements of machined parts.

During the replacement process, the debugging of the X, Z axis and the spindle is relatively smooth. However, the control of the rotating turret has certain difficulties. The reason is that the GSK980TA numerical control system can only control the 12-station rotary knife ± moss which generates the BCD code as the tool position feedback signal by the angle encoder, and the turret position control of this machine tool is controlled by the counting switch, which solves this problem. There are two methods: 1 Replace the rotary turret with angle encoder, the cost is higher, about 30,000 yuan. 2 Convert the count switch signal to a BCD code signal. In the transformation, we chose the FX1S-30MT PC produced by Mitsubishi Corporation of Japan. The counting switch signal is converted into a BCD code signal by programming of the PLC program. The signal conversion flow chart is: the counting signal sent, C30 is the power-off memory type counter, Y000~Y003 is the BCD code signal, and X000 is the tool position adjustment switch signal. Once the tool number is wrong, you can click this button to force the count and adjust the adjustment until the tool number is correct.

Due to the limitations of the input and output signals of the GSK980TA CNC system, the hydraulic chuck release/clamp control of the machine spindle and the extension/contraction control of the tailstock cannot be realized. Therefore, this part of the control program was programmed in the Mitsubishi PC. Press the chuck control button, the chuck is closed, and then press again, the chuck opens. The same is true for the control of the tailstock. (Go to page 70) The effect of the wave line is not ideal. Therefore, it can be implemented with the PLINE command.

This can be done by the following command sequence (see). Use the PLINE command to draw the fold line freely in the appropriate place of the graph. To ensure the area is closed, the fold line can be beyond the outline of the graph. (a) Use the SPLINE option in the PEDIT command to curve the polyline. Fit (b) then use the TRIM command to trim the out-of-bounds portion, and then fill the hatched line in the enclosed area (c) to complete the full image.

The SPLINE option in the polyline editing command is based on the polyline through which the vertices of the original polyline pass, and the control polygon is fitted to generate a B-spline curve. The generated curve can be changed by modifying the position of the control vertex. shape.

Mastering the above principles, it is also very convenient to use the polyline command to draw the axis end break symbol. You can first call the PLINE command to draw a polyline 1*2*3*4?5 where endpoints 1, 5 must be captured with endpoints to ensure that the first and last points are on the contour line, and 3 points can be used to capture the nearest point to ensure that 3 points are on the axis. , 2, 4 points can be taken at the appropriate position (see a) draw 5? 6? 3 in the same way (see b) use the SPLINE option in the PEDIT command to curve fit the polyline, and then Fill the hatch line in the enclosed area and complete the broken symbol drawing (see c). Multi-rounding processing to place the entities to be thickened on a layer through the layer for unified management. If the graphic is printed directly in the CAD system, because the CAD graphic is a vector image, the line width will not change due to the graphic scaling. However, if you want to paste the CAD graphic into Word and typeset it in Word, the width of the line will follow. The scaling of the graphics changes, affecting the aesthetics of typography, but if you use polylines to draw and edit graphics in CAD, you can solve the problem.

Use the polyline to widen the outline. If the outline is a straight line and an arc, you can use the W option in the PEDIT command to directly unify the line width. This method is simpler. If it is a circle, you can't use this command to widen it. You can use the following method: first use the Break command to break a small hole on the circle, then use the W option in the PEDIT command to set the line width. Thick, then use the Close option to close. To bold ellipse and elliptical arc, first set the system variable PELLIPSE to 1, turn the true ellipse into a polyline ellipse, and then bold it in the same way as the line. Note that the Rectangle and Polygon commands can also be edited using the PEDIT command in CAD.

Through several examples in my practical application, I summarized some techniques for drawing with polyline. It can be seen that flexible application of polyline can improve the drawing efficiency of AutoCAD and make the drawing more flexible and convenient. At the same time, it should be noted that AutoCAD is a platform-based CAD software. The key is how to master it and use it to make full use of it.

In the engineering, some common base plates are often set with rounded corners. If you draw the shape, you can also use the LINE command to complete the graphics. However, when you use the FILLET command to round the graphics, if you directly select the two sides, you only have to The angles between the two sides are processed. However, if you use a polyline to draw when drawing, you can complete all the rounded corners (for example) (upper page 67) in the chamfering process. X007 is the hydraulic chuck control button. Y014/Y015 is the output signal, and the clamping/release of the chuck is realized by the relay control solenoid valve.

6 Replace the CNC system experience in the debugging process, must take into account the safety of the operation, add some protection procedures to avoid damage to the human body and equipment caused by operational errors. If the spindle rotates, the hydraulic chuck action is invalid. When machining parts, the guard door must be closed.

(Finish)