The finished capacitive touch screen needs to go through more than 40 processes. When we ship it to the customer and assemble it into a complete machine, there will be a certain loss of the product due to the improper operation of the staff. Let's talk about today's industrial touch screen maintenance points:
1: Check the parts
The quality inspector inspects the appearance of the parts (1. Visually check whether the component equipment is deformed, discolored, damaged, burned, and whether the filament is on after power-on). These problems often affect the touch screen. Determine the relevant cause of the failure and then repair the touch screen.
2: Poor contact
When the insulator is energized or not, manual tapping or pressing is an effective maintenance method for faults caused by poor contact, and it is easy to find problems such as false welding and poor contact.
3: Replacement parts
When a part of the component cannot be determined whether it is good or bad, it can be replaced and replaced with a good part. If troubleshooting proves that the original part is faulty, replacement is the most time-saving quick repair method for individual parts that are inconvenient to measure!
4: Current detection
The test current is one of the maintenance current touch screens: it is mainly used to measure the load current and working current of transistors and integrated circuit blocks to detect whether the load of the integrated circuit, transistor and/or integrated power supply is normal, etc. As long as the measured current is normal, it can be concluded that the touch screen circuit is basically normal. However, during the measurement, the current is very different from the normal value, which means that there must be something wrong with the current. You can analyze the cause of the problem and then check.
5: Water inlet fault detection
1: Prepare the disassembly tool.
2: Self-made resistance measuring probe. Remove the touch screen of the machine and watch. There are small water marks in the transparent place, and the amount of water is small. The four-wire resistance (2k gear) of the cable of the touch screen rushes to the left and starts to count. It is found that 12, 23, 34 and 14 have resistance values (usually 13, 24 have resistance values, 14, 23 should have no resistance values and no contact state). Therefore, it is judged that there is a short circuit inside.
3: Handle Touch Screen It moved with a small screwdriver for a week, but there is no water inlet gap on the pipeline, so use a utility knife to cut slowly around the corners, remembering the glass layer along the bottom. After prying, blow with the hot air of the hair dryer for about 10 seconds, listen to the recording, and blow again. While the prying device is hot, compress and engage it, then measure the resistance of the four wires with a multimeter (13 and 24 have resistance values of 290 ohms and 240 ohms, respectively) Touch screen repair.
4: Seal and dry with silicone rubber along the edge, install the surface shell (double-sided adhesive bonding), install, test, touch screen correction, everything is normal.
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2022 05/28