Friends who often use button switches need to know about it.
Release time：2019-03-19 Clicks： Click
Friends who often use button switches need to understand some problems, you should be clear, because they often touch the button switches, so these knowledge are introduced to you.
The manufacturer of button switch briefly introduces the advantages of small contact resistance charge, precise operating force error and diversified specifications of button switch. It has been widely used in electronic equipment and white household appliances, such as video and audio products, digital products, remote controllers, communication products, household appliances, security products, toys, computer products, fitness equipment, medical equipment, banknote checker, etc. Laser pen keys and so on.
Because the button switch is directly replaced by conductive rubber or pot switch hardware bullet, such as medical equipment, TV remote controller and so on, in environmental conditions (pressure less than 2 times elasticity/ambient temperature and humidity conditions and electrical performance) for large-scale equipment and high-load buttons.
About the foot position of five-pin key switch: two pins are in a group, four pins are connected when the switch body is properly pressed, and the fifth pin is grounded.
Key switch is the fourth generation switch product developed with the development of electronic technology. The earliest volume is 12 mm * 12 mm, 8 mm * 8 mm, and now it is 6 mm * 6 mm. There are three kinds of product structure: vertical, horizontal and horizontal with ground ends. Now there are two kinds of combination (3M, 4M, SM, 6M, SM) and potentiometer key switch combination, which meet the requirements of various domestic electronic products. Installation sizes are 6.5 mm*4.5 mm, 5.5 mm*4 mm and 6 mm*4 mm. There are 4.5mm*4.5mm miniature key switch and chip key switch abroad. The chip key switch is suitable for surface assembly.
Now there are the fifth generation of switch - thin film switch, which has the same function as the key switch. It is mainly used in electronic instruments and CNC machine tools, but it has large resistance and poor handle. In order to overcome the phenomenon of poor hand feeling, there are also contact reeds installed in the membrane switch instead of using silver layer as contact point.
The key switch is divided into two categories: using metal reed as the contact plate of the switch to call the key switch, the contact resistance is small, the feel is good, and there is a "tick" crisp sound. The switch using conductive rubber as contact path is called conductive rubber switch. The switch feels good, but its contact resistance is large, generally in the range of 100-300 n. The structure of the key switch is to move down by the key, so that the contact spring or conductive rubber block contacts the welding plate, forming a path.
The operating force of the key switch is related to the state of the reed. The starting force is proportional to the compression distance of the reed. When the reed is compressed to 5% to 70%, the operating force suddenly decreases, accompanied by "ticking" sound. There are generally two kinds of structure of rubber switch for guide tortoise. Operating force curves vary greatly with the geometry of rubber blocks.