As we all know, PET protective film plays a role in transmitting instruction information in electronic whole machine products.
There are many varieties of switches, and their development is constantly updated with the progress of electronic complete machine products.
In 1950s, with the toggle switch of the struggling element, the toggle switch and the changeover switch dominated;
In 1960s, a combination switch represented by a key switch appeared to complete a simple function conversion;
With the expansion of the application field and the increase of the function of the whole machine, the keyboard switch of conductive rubber appeared in 1970s, and the PET protective film was a new type of electronic device researched and developed in the late 1970s s and early 1980s s, it is a product that meets the needs of the development of electronic complete machine products to miniaturization, digitalization, intelligence and multifunction.
PET protective film is a switch made by printing contact circuits with conductive paste on flexible polycarbonate or polyester film, which is a kind of contact switch.
PET protective film is flat type, multi-layer combination and sealed structure. It is an assembly of electronic whole machine control system integrating key switch, panel function mark, reading display transparent window, indicator light window hole and circuit. It has the following characteristics :(1)
The service life of durable PET protective film can generally reach more than 1 million times. The reason for such a long service life is that the switch action is only realized by the vertical bounce of the elastic film.
Although the elastic film has undergone millions of peristalsis, the creep amplitude is very small, only 0. 1 ~ 0. 3mm (Both switch stroke)
In addition, the rationality of material selection is far from reaching the yield limit of the film, so the film material can withstand more than 1 million times of life without deformation.
On the other hand, the contact of the switch is vertical contact, and the wear is very small;
However, the contact of screen printing can form enough thickness, and a layer of conductive carbon is printed on the silver paste contact to achieve the purpose of high wear resistance and self-lubrication, so the life of PET protective film, it is more than ten times higher than mechanical contact switch. (2)
The sealing performance is good, because the PET protective film is the overall sealing structure, the contact of the switch is not eroded by harmful gases, and it is not easy to oxidize;
It has the characteristics of waterproof and dustproof, so it is more suitable for various harsh environments. (3)
Volume small quality light and structure reliable PET protective film in design on can arrangement combination into film keyboard its is set density big and it is by multi-layer film made of seal sheet-structure, all switch between the cable and leader is by screen printing one-time complete total thickness in 1 ~ 3mm and the narrowing of the volume reduce the quality improve the reliability. (4)
The color is rich and the appearance is beautiful the PET protective film can reflect the individuation in the design of the color pattern according to the design concept of the user, and the comprehensive characteristics of the beauty of the material, the beauty of the decoration and the beauty of the craft in the decorative effect. (5)
Reduce the matching Cost of mechanical and electrical products. Traditional mechanical switches need to be welded during installation and even matched with fixed supports.
The PET protective film is installed in the adhesive type. As long as the back adhesive paper is removed, it can be firmly pasted on the surface of the whole machine. The lead outlet is inserted into the socket of the rear circuit of the whole machine, and the circuit can be connected in an instant.
It saves labor and material, and reduces the supporting cost of the whole machine.