Why should the Membrane Keypadbe designed as a button bump?

Why should the Membrane Keypadbe designed as a button bump?

Why is the membrane switch designed as a raised key, and what are the advantages? Want to know? So, let's take a look at it:

The key drum is used to press the key area upward against the mask layer. The method has strict requirements on temperature and pressure according to the natural characteristics and concave-convex characteristics of the film switching material. The basic form is as follows:

(1) Frame line prominence: used when the edge of the switch is prominent.

(2) Planar convex: the whole switch is higher than the surface of the panel.

(3) Ball convex: used for processing spherical buttons.

(4) Box line convex + ball convex: not commonly used.

Advantages of the membrane switch design as a raised key:

(1) Improve the decorative effect of the appearance of the film switch.

(2) The operator's tactile sensitivity.

(3) The range of the binder is given accurately.

(4) Improve the recognition speed.

Factors to consider when designing the Membrane Keypadas a raised key:

(1) Special mold processing is required.

(2) Increase the limit temperature of polyester to 50℃.

(3) The height of the bulge should not exceed 1.5 times the thickness of the material.

(4) The plane protrusion is at least 3mm or 5mm from the edge.

(5) The key distance edge of the border line should be at least 5mm.

(6) Too much force will reduce the mechanical life (for polycarbonate masks, the mechanical life should be able to operate no less than 100,000 times).

The key cost of the Membrane Keypadis relatively low, and it is also simple to make. And the quality of the finished product is also suspicious of many people's attention, the Membrane Keypadis very common in our life, the key of each switch is not many, and the label is also very clear, we can quickly and easily distinguish the key function of the film switch.

After checking the Membrane Keypadcircuit, it can be found that the structure of the Membrane Keypadis composed of three layers of printed circuit, two layers of conductive coating on the upper and lower, the corresponding contact will appear in each button below, and a layer of isolation layer, the same key (or hollow) with circular contact in the middle, when the keyboard is pressed, the connection of the upper and lower two layers of circuit is completed, and the corresponding signal is generated.