What are the excellent methods for selecting and checking light-touch switches?
Release time：2019-06-18 Clicks： Click
How to select the light touch switch? What is the specific selection method? Let's give you a detailed introduction.
The key factors affecting the quality of light touch switch are the protection, solderability, reliability of conduction, life, handle, production process and installation size of light touch switch.
Firstly, the pin base material is the pin base material, and the pin base material of the light touch switch is brass or phosphorus copper (low grade is iron). In order to reduce the contact resistance, the pin is basically silver plated. The SO2 gas in the silver meets the air will oxidize, which directly affects the solderability and contact resistance of the switch. Therefore, the high-quality light touch switch should first be the pin base material. The control of silver plating thickness and silver plating process is in place. The order of silver plating on the market is as follows:
Silver plating thickness: 0.3um or more (silver), 0.2um (thin silver), 0.1um (white)
Silver plating process: nickel pre-plating and silver re-plating on the substrate, copper pre-plating and silver re-plating on the substrate, and direct silver plating on the substrate
Whether the protective agent treatment is carried out after silver plating on the substrate or whether the switch has the function of dust-proof and waterproof is very important, otherwise, even better silver plating treatment, the switch will be oxidized.
Secondly, the key factor affecting the reliability of conduction is the structure of contact point. Because the function of touch switch is contact point and shrapnel conduction, the larger the contact surface is, the better the contact surface is. The contact surface is determined by the structure. There are probably three types of structures in the market. The order of advantages and disadvantages is as follows:
Bubble (crater type) "O contact", grooved type "2 contact" and flat bubble type "1 contact"
Thirdly, life and feel are determined by the stroke of the light touch switch and the cooperation of the shrapnel. The shorter the stroke, the lighter the sound, the longer the life, on the contrary, in the case of fixed shrapnel technology, the life of the light touch switch is mainly determined by the stroke or sound.
In addition, the key factor to determine the life of shrapnel is stamping technology. The stamping technology in Japan and Taiwan is very popular in China. Therefore, in the case of technological upgrading, whether the requirements for imported materials are reduced or not, such as 160gf shrapnel life, there are four main types in the market.
Fourth is the production process, after having accessories, the final impact of quality is the assembly process, assembly process depends on the management ability of the production company, staff quality meaning and quality assurance ability and other factors, different assurance ability of the final product quality will certainly be different, market assembly methods are artificial and machine, machine set. Loading cost is low, but product quality is low, and manual assembly cost is high, but the quality is also high.
Fifth, factory inspection, the methods and items of factory inspection also affect the quality of the final light touch switch, such as appearance, feel, conduction, resistance and other items are spot inspection or full inspection, such as the rejection rate required by some large factories is measured by PPM or zero defect, it is necessary to set up spot inspection or products after the factory inspection set up full inspection. Quality inspection and other processes.