1.Characteristic
As is known to all, Membrane Keypad plays a role in delivering instruction information in electronic products. There are many varieties of Switch , its development with the progress of electronic complete machine products and constantly updated. In the 1950s toggle switch, toggle switch, switch conversion dominant position; In the 1960s, the combination switch represented by the key switch appeared to complete the simple function conversion; With the expansion of the application field and the increase of the function of the machine, the Keyboard switch of conductive rubber appeared in the 1970s, and the Membrane Switch is a new electronic device developed in the late 1970s and early 1980s. It is the product of the development of electronic machine products to miniaturization, digitization, intelligence and multi-function.
Thin film switch is a kind of contact switch made by printing contact circuit with conductive paste on flexible poly-carbonate or polyester film.
Membrane switch is planar, multi-layer combination, sealed structure, is set Membrane Circuit switch, panel function mark, reading display transparent window, indicator window hole and circuit as one of the electronic complete machine operating system assembly.

It has the following characteristics:

(1) durability
The life of the Membrane Switch can generally reach more than a million times, the reason for such a long life is that the switch action is only realized by the vertical movement of the elastic film. Although the elastic film after millions of peristalsis, but because of the creep amplitude is very small, only 0.1~0.3mm (both switching stroke), in addition to the rationality of material selection, far from reaching the yield limit of the film, so the film material can withstand more than one million times of life without deformation. On the other hand, the contacts of switches
Is vertical contact, wear is very small; And Screen printing contacts can form enough thickness, and in the silver paste contact in the printing of a layer of conductive carbon, in order to achieve high wear resistance, self-lubrication, so the life of the film switch, than the mechanical contact switch tens of times more than.
(2) Good sealing performance
Because the Graphic Overlay Membrane Switch is the overall sealing structure, the switch contacts are not corroded by harmful gases, not easy to oxidize; With waterproof and dust-proof characteristics, so more suitable for all kinds of harsh environment.
(3) Small size, light weight and reliable structure
Membrane switch keyboard in the design of permutation and combination into film, its setting density is big, and it is made up by multiplayer film sealed chip type structure, all cables between switches and lead by screen printing is one-time completed, the total thickness in 1 ~ 3 mm, narrow the volume, therefore, reduce the quality, improve the reliability.
(4) Rich color and beautiful appearance
Membrane switch can be based on the user's design idea, in the design of color patterns reflect personalized, in the decorative effect of the body to show the comprehensive characteristics of the beauty of material, decoration and process.
(5) Reduce the supporting costs of mechanical and electrical products
Traditional Silicone Rubber Keypad, in the installation of welding, or even with a fixed bracket. The installation of the film switch is paste type, as long as the back adhesive paper is removed, it can be firmly stuck on the surface of the machine, and the lead outlet is inserted into the socket of the rear circuit of the machine, and the circuit can be connected instantly. Save labor, save material, reduce the whole machine supporting cost.

2.Application

Membrane Keyboard is a non - self - locking switch. Suitable for switching power less than 1W ah, the maximum operating voltage: 42V (DC) or 25V (DC), the maximum operating current is less than 100 mA working occasions. Can be widely used in all microcomputer, NUMERICAL control. Intelligent instruments, meters and both discrimination, memory functions of electronic circuits in many fields.