Metal dome button, it is a PET sheet containing a metal sheet, used as a switch on PCB or FPC circuit boards. It plays an important tactile switch between the user and the instrument.
Compared with traditional silicone keys, metal dome keys have a better feel and longer life, and can indirectly improve the production efficiency of various types of switches using conductive films. The metal sheet on the metal dome button is located on the conductive part of the PCB board (mostly located above the golden fingers on the circuit board). When pressed, the center point of the metal dome is recessed and touches the circuit on the PCB, thereby forming a loop. When the current passes, the whole product can work normally. This is how the metal dome button works.
We already know quite a bit about the metal dome buttons in the membrane switch panel. However, there are several types of metal dome keys. Next, we will make a classification for everyone.
Classified by structure
1. Single layer structure
This is the simplest structure. The metal sheet is located under Mylar (a layer of PET with glue) and has vent holes to ensure basic feel and use.
2. Double structure
Unlike the single-layer structure, it has an extra layer of Spacer. The metal sheet is better attached to the Mylar, and keeps good contact with the circuit board, and has a better hand feeling (similar to the dome of a membrane switch). In addition, the vent holes on the double-layer structure can more effectively prevent the PET layer from being scratched by the burrs of the metal sheet, and also prevent dust from entering the PET layer.
3. EMI printing
On the top of Myalr (viewed from the front of the product) is printed a layer of silver paste, which is called ESD (Electrostatic Discharge Control). EMI is mainly used to prevent the static electricity generated by electronics and peripheral products from damaging the target electrical appliances.
4. Rubber
A layer of Rubber glue (for silicone paste) is printed on the Mylar or EMI layer, so this type of product can be firmly adhered to PCB/FPC and other circuit boards.
5. Metal dome buttons
The metal sheet is embossed to meet the specific structure combination and improve the feel of the metal sheet. This type is widely used in the embossed buttons of our membrane switches.
Classified by button pressure
1. Button pressure range: 50-80g
Generally applicable to the silicone keys of computer keyboards and calculator keys. The pressing force in this range is not high. It is easy for users to press, suitable for buttons that need to be clicked frequently.
2. Button pressure range: 80-120g
Generally suitable for household appliances keys, remote control keys, etc. The pressing force is appropriate, the hand feels comfortable, and the resilience is better.
3. Button pressure range: 120-180g
Generally suitable for audio equipment, industrial instruments, mechanical remote control, the pressing force is much larger than the second type. The resilience is also superior, but it is not suitable for use in products with frequent clicks.
4. Button pressure range: 180g or greater
Generally, this kind of pressure button is relatively rare, and it is suitable for special industries, such as medical, aviation and other industries, which require frequent button operations in a short time.
Comments
Post a Comment