Why do membrane keyboard manufacturers design their keys to be raised?

Why is the membrane switch designed as a protruding key, and what are its advantages? Do you want to know?

The key drum is used to press the key body area upwards onto the mask layer using a drum press machine. This method has strict requirements for temperature and pressure based on the natural and concave convex characteristics of the membrane switch material. The basic form is as follows:

(1) Frame protrusion: Used when the edge of the switch protrudes.

(2) Flat convex: The entire switch is higher than the surface of the panel.

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

(4) Frame convex+ball convex: not commonly used.

The advantages of designing membrane switches with raised buttons are:

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

(2) The operator is sensitive to touch.

(3) Accurately provided the range of the adhesive.

(4) Improve recognition speed.

Factors to consider when designing a membrane switch as a raised key:

(1) Special mold processing is required.

(2) Raise the maximum temperature of polyester to 50 ℃.

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

(4) The distance between the flat protrusion and the edge should be at least 3mm or 5mm.

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

(6) Excessive force can reduce the mechanical lifespan (for polycarbonate masks, the mechanical lifespan should be able to operate no less than 100000 times).

The key cost of membrane switches is relatively low and the production is also simple. The quality of the finished product is also questioned by many people's attention. Membrane switches are very common in our lives, and there are not many keys for each switch. The labels are also very clear, and we can quickly and easily distinguish the key functions of membrane switches.

After checking the circuit of the membrane switch, it can be found that the structure of the membrane switch is composed of three layers, with printed circuits for conductive coatings on the upper and lower layers. Each button below will have corresponding contact, and there is an isolation layer with circular contacts in the middle of the same button (or hollow). When the keyboard is pressed, the connection between the upper and lower circuits is completed, generating corresponding signals.