Wide variety of switches and application characteristics of a membrane switch
Updated：2011-10-13
1 Features
As we all know, the switch in the electronic products in order to pass information plays a role. There are many varieties of the switch, the development of electronic products with the progress of constantly updated. The 1950s to struggling component button switch, toggle switch, switch the dominant; 60 years there have been represented by a combination of keys switch switch to complete a simple function of conversion; With the expansion of application fields and The increased capabilities of the machine, 70 years appeared conductive rubber keypad switches and membrane switch is in the late 1970s early 1980s research and development of a new electronic device, which is responsive to the miniaturization of electronic products, digital, intelligent, multi-functional product development needs.
Membrane switch is on flexible polycarbonate or polyester film printed with conductive paste made of the switch contact circuit is a contact switch.
For the planar membrane switch, multi-layer, sealed structure, is a key switch, panel markers, readings transparent window, light apertures and the whole circuit as one of the electronic control system assembly.
It has the following characteristics:
(1) durability
Membrane switch life in general can reach more than a million times, the reason why there is such a long life, is only due to the switching action of the vertical direction by the elastic film bounces achieve. Flexible film even after millions of peristalsis, but the magnitude of creep is very small, only 0.1 ~ 0.3mm (both switch trip), combined with material selection is reasonable, far short films yield limit, so the thin-film materials can be bear more than one million life without deformation. On the other hand, the switch contacts
Vertical contact, wear very little; and screen printing of sufficient thickness to form contacts, and by printing silver paste contacts on a layer of conductive carbon in order to achieve high wear resistance, self-lubricating purposes, the film switch life, increase than the mechanical contact switch for more than a few times.
(2) sealing performance
As the membrane switch is the overall tightness of the structure, the switch contacts from harmful gases, erosion, oxidation is not easy; with a waterproof and dustproof features, and thus more suitable for harsh environments.
(3) small size, light weight and structural reliability
Membrane switch design can be arranged to form a membrane keyboard, set density, and it is a combination of multi-layer film sealing sheet structure, the connection between all the switches and Lead line once completed by screen printing The total thickness of 1 ~ 3mm, thus reducing the volume, reducing the quality and improve reliability.
(4) The rich colors and beautiful appearance
Membrane switch design based on the user’s idea of the color pattern in the design reflects the individuality, reflected in the decorative effect on the material beauty, decorative beauty, arts, crafts integrated features.
(5) reduce the cost of supporting mechanical and electrical products
The traditional mechanical switches, the installation requires welding, even with the mounting bracket. The membrane switch is installed as a paste-type, if thrown back tape, the machine can be securely attached to the surface, it leads into the whole rear exit outlet on a circuit, can be instantly connected to the circuit. Labor saving, material saving, reducing the cost of supporting the machine.
2 Application
Membrane switch is a non-trivial since the switch. For switching power less than 1W ah, the maximum operating voltage: 42V (DC) or 25V (DC), the maximum operating current of less than 100 mA in the workplace. Can be widely used in all computer, numerical control. Intelligent instruments, meters and both judge and memory in many areas of electronic circuits.