Membrane switch product introduction
Membrane switch, also known as the light-touch keyboard, the use of planar multi-layer combination of the overall sealing structure, is the key switch, panel, marking, symbols, display and liner sealed together with the set of optical, mechanical, electrical integration of a new type of electronic components, is the appearance of the electronic products of the fundamental structural changes, which can be used to replace the keys of the conventional discrete components, more reliable execution of the operating system tasks. It can replace the keys of conventional discrete components and perform the tasks of operating system more reliably.
Membrane switch has good waterproof, dustproof, oilproof, anti-hazardous gas erosion, stable and reliable performance, light weight, small volume, long life, easy to install and connect, the panel can be washed and the character is not damaged, colorful, beautiful and generous advantages. The use of membrane switches make your products more contemporary. Membrane switch main types of membrane switch panel is a rigid or flexible printed circuit board as a substrate, the installation of tactile or non-tactile keys, and then coated with plastic (polycarbonate PC, polyester PET, etc.) printed with colorful and decorative patterns of film panels composed of a set of switching and decorative functions as one of the electronic components, is a new type of man-machine dialogue interface. The connection between its switching circuit and the whole machine can be completed by welding or plugging.
The working principle of membrane switch
When the panel is not pressed, the membrane switch is in the conventional state, its upper and lower contacts are disconnected, the isolation layer on the upper and lower lines to isolate the role of; when the panel is pressed, the upper circuit of the contacts downward deformation, and the lower line reintegration and the line to make the line through the line after the conduction of the line to the external connection of the instrument (substrate) to the signal to achieve its corresponding function; when the panel is released, the upper circuit of contacts down deformation, with the lower line reintegration to make the line through the conduction line to external connection instrument (substrate) to realize its corresponding function. When the finger is released, the upper circuit contacts rebound back, the circuit is disconnected, the circuit triggers a signal.
Membrane switch composition
Generally speaking, the common membrane switch is mainly composed of six layers of material, in accordance with the order from the table to the inside are the panel, the surface adhesive, the upper circuit, the isolation layer, the lower circuit, the bottom adhesive. The following are introduced separately the structure of each layer:
1. Panel: the panel is the whole membrane switch "coat", in the appropriate arrangement of the key on the basis of different colors, patterns, key shape, the whole membrane switch to play a necessary decorative role. The main role of the panel layer is to play the role of marking and key, so the choice of materials must have high transparency, high ink adhesion, high elasticity, anti-folding and other characteristics.
2. Upper circuit, lower circuit: the upper and lower circuits are the electrical components of the membrane switch, but also the switch's "off" "key" is located, and its performance directly affects the switch's electrical performance is good or bad, mainly by the film printed on a layer of conductive material and formed. It is mainly formed by printing a layer of conductive material on the film. The upper and lower circuits bear the two electrochemical roles necessary for the closure of the switch, the thickness of which is generally within 0.05 - 0.175MM, the most common is to use 0.125MMPET.
3. The surface adhesive, the isolation layer, the bottom adhesive: the three layers of the structure of the material are double-sided adhesive, due to the different positions in the switch structure and have different names. The three layers of double-sided adhesive by their respective levels of different and different thickness, this is mainly based on the thickness of the switch, the operating force of the key to decide.