What technical factors are involved in positioning and turning
1. Purpose of Positioning
1. The basis for turning over. To install circuit boards using positioning pins, positioning holes must be punched first.
2. Limit the direction of turning. The use of asymmetric positioning holes can ensure that the circuit board can be installed only in the case of non-turning and correct turning.
3. Identify the hole. The double-sided board needs to be metal holed. When it is installed again, there are only many holes on the copper-clad board. With the logo hole, it can be easily distinguished.
2. Factors affecting turning
1. The quality of positioning.
2. The quality of transmission components.
3. Number and location of positioning holes.
4. Engraving machine verticality.
3. Factors affecting positioning quality
1. The orientation of the positioning limit flip must be consistent with the direction defined on the software. Generally guaranteed by the engraving machine software.
2. Positioning bit and positioning pin. The positioning hole must be drilled with a drill bit, and the diameter of the drill bit can only be slightly larger than the positioning pin. If the diameter of the drill is too large, it will affect the accuracy; if the diameter of the drill is too small, the positioning pin will not be put in, and forced installation will also affect the accuracy.
3. Positioning depth. It is generally required that the positioning pin is inserted into the platform more than 1 mm, but it is not necessary to exceed 2 mm. If the positioning hole is too deep, it will affect the service life of the platform; if the positioning hole is too shallow, it will obviously affect the accuracy.
4. The relationship between the quality of the transmission parts and the turning
The quality of the transmission component has a great influence on the turning, and the deviation of the transmission component can be roughly judged according to the deviation of the circuit board.
1. The quality of the transmission components with the same horizontal plane and turning direction has a great influence on turning.
2. The quality of the transmission components whose horizontal plane and turning direction are inconsistent also has a certain influence on turning.
3. The quality of the vertical plane transmission components has almost no effect on turning.
Taking left and right turning as an example, the influence of X-direction transmission components is greater, the influence of Y-direction transmission components is smaller, and the Z-direction transmission components have little effect.
Fifth, the relationship between the number and location of positioning holes and turning
If everything is in an ideal state, then the number and location of positioning holes are irrelevant, but this is not the case.
1. Two-point positioning. Based on the two-point positioning design, the two sides located in the center of the circuit board have the best effect. The biggest advantage of this method is that it will not cause the circuit board to rotate due to the quality of the engraving machine transmission components, and the installation is relatively convenient. However, the verticality of the horizontal plane of the engraving machine will be particularly obvious. And it is easy to reduce the accuracy of the circuit board due to the deviation of the user's operation.
2. Four-point positioning. Based on the four-point positioning design, it is best to locate near the four corners of the circuit board (the precise position is related to the accuracy curve of the transmission component). However, it is most convenient for users to operate near the four corners of the circuit board. This method can not only fix the horizontal position, but also play a certain role of fixing up and down, while effectively avoiding errors caused by user operations. But if the quality of the instrument is not high, it will cause the phenomenon that the routing board rotates after turning over.
Take the left and right flip as an example, the circuit board height is 100 mm. It is best to choose Y coordinate near 10 and 90, and it is most convenient for users to choose Y coordinate near 0 and 100.
6. Verticality of engraving machine
1. The verticality of the horizontal plane. If the horizontal plane is not vertical, the original rectangular and trapezoidal designs will be deformed, resulting in difficulty in installation after turning over and the circuit board rotating.
2. The verticality of the main axis. The positioning hole is drilled with a drill. If the spindle is not vertical, it will definitely cause a large deviation.
3. The perpendicularity between the vertical direction and the turning direction. Many manufacturers believe that as long as the main axis is vertical, it is not important whether the Z direction is vertical, but this is obviously wrong. If the Z direction is not vertical, the drill hole is not a vertical drill hole, and the hole shape will have a large deviation.
7. Other factors
1. The rigidity of the engraving machine transmission related parts. Because some transmission components take into account the load-bearing function, excessively high weight brings mechanical bending, which directly affects the accuracy of the transmission components and thus the accuracy of turning.
8. User operation matters needing attention
1. When installing the circuit board, first place the circuit board on the platform, align the positioning holes, and insert the positioning pins. Some users are accustomed to insert the positioning pin on the platform first, and then install the circuit board. In fact, this operation is wrong and will cause serious deviations.
2. When removing the circuit board, first remove the positioning pin, and then remove the circuit board. This will not damage the positioning holes on the platform.
3. When removing the circuit board, do not pry too hard. Excessive bending of the circuit board will cause a situation that cannot be restored for a while, resulting in unevenness. Once such a situation occurs, additional treatment is required.
Weihai Tong Park Arts & Crafts Co.,Ltd , https://www.whtongpark.com