Six Common Problems and Troubleshooting of Light Touch Switch
Release time：2019-06-03 Clicks： Click
There are always some problems and faults when using the light touch switch. What are the specific solutions? Here's a detailed introduction for you.
Question 1. Feeling
Many customers have been responding, many suppliers sent samples feel very consistent, but when it comes to mass production feel different. In fact, this problem is very common. We all know that the handle and push force of the switch are controlled by shrapnel. We often say that the shrapnel is divided into phosphorus-copper shrapnel and stainless steel shrapnel. At present, many manufacturers choose phosphorus-copper shrapnel in order to save costs. The price performance of phosphorus-copper shrapnel is relatively high, which is also the reason for its widespread use. However, the imported UV lamp tube price phosphorus copper shrapnel will change after furnace temperature, shrinkage is serious, which leads to poor hand feeling. Stainless steel shrapnel with high pressure spray gun will not have this problem, but the cost of stainless steel shrapnel is relatively high, which leads many manufacturers to take risks to choose phosphorus-copper shrapnel, so when purchasing lightly touch switch, we must ask the next question clearly.
Question 2. Adhesion
Ultra-thin touch switches are commonly referred to as thin film switches. Thin switches need thin film matching, so that they can be really thin. However, many thin films have poor temperature resistance and will fall off after the furnace is over. Our professional term refers to adhesion, in fact, is the adhesion of thin film. Imported PI film has a good control of this point. Its adhesion is 400g, which is very consistent with the use of switches. How to be too light and often fall off? If the switch is too heavy, it will not move. Many manufacturers choose cheap domestic PI film to save costs, the switch is very prone to adhesion problems.
Question 3. Cover Shedding
How did a good touch of the switch cover come off? First of all, we need to understand the structure of the switch. The cover of the switch is on the back cover. This is a constant production process for thousands of years. Familiar people will find that the lid is fixed by four rivets on the base, so as long as the four rivets are loose or the rivets shrink or deform after high temperature, the lid will fall off. Preventive cover only pays attention to the following two problems. One base should be made of heat-resistant material, the second riveting point should be riveted and fixed well, and the above two problems should be solved perfectly.
Question 4. Easy press does not lead
In wet weather, the shrapnel that touches the switch is easy to be oxidized, and the contact performance after oxidation is not as good as before, that is, there is a problem of light press and no conduction. Many consumers have also dismantled the switch and found that there will be a small black spot on the shrapnel, which is the effect of the shrapnel oxidation. Therefore, it is suggested that the electronic products we do not normally use should be placed in a relatively dry place and the prepaid electronic parts should be oxidized.
Problem 5. High resistance
What effect does high resistance have on lightly touching switches? If the resistance is high, it means that the contact area between the shrapnel and PIN foot of the switch is too small. The contact area is too small to cause the switch to be contacted. Once the switch is not contacted, it will be bad. Therefore, we should be careful about the resistance of the switch, the shrapnel and PIN foot for plating requirements are relatively high, plating resistance will be low. After the life test, the surface of the shrapnel will be worn. If the electroplating is thin, the resistance will be high and the switch will be bad.
Question 6. Stay still after passing the furnace
A good touch switch, after reflow soldering experience, can not press, very pitiful. Many customers are also responding to this question, so what caused it? The patch switch is tightly attached to the PCB, and the PIN foot will be solder paste. If the hole of the steel mesh is slightly larger, the solder paste can easily flow into the inside of the switch. If there is foreign matter in the inside of the switch, it will certainly affect its journey. The most common thing is to press it still. Another situation is that the sealing performance of the switch is not good, flux flows into the inside of the switch, so the problem arises. Therefore, it is suggested that customers should pay attention to this problem in the production process.