Film-type switching circuit board with pressure-regulatable air chamber

Abstract

A film-type switch circuit board for computer keyboard is disclosed. Said computer keyboard is composed of base, at least one key structure and said circuit board, which consists of upper film circuit layer, lower film circuit layer and at least one pressure-regulating air chamber. A preset space containing air is between the upper contacts of upper film circuit layer and the lower contacts of lower film circuit laeyer and is communicated with said pressure-regulating air chamber. Said key structure can make upper and lower contacts in touth to generate keystroke signal.

Description

technical field [0001] The invention relates to a membrane switch circuit board, in particular to a membrane switch circuit board with a pressure regulating air chamber. Background technique [0002] see figure 1 and figure 2 . figure 1 It is a schematic diagram of a conventional membrane switch circuit board 10 used in a computer keyboard 12 . figure 2 for figure 1 A schematic diagram of the switch unit 32 of the membrane switch circuit board 10 shown. The membrane switch circuit board 10 is used in a computer keyboard 12 for generating key signals. The computer keyboard 12 includes a base 14 and a plurality of key structures 16 , and the membrane switch circuit board 10 is disposed between the base 14 and the plurality of key structures 16 . The membrane switch circuit board 10 includes an upper membrane circuit layer 18 , a lower membrane circuit layer 22 , and a plurality of switch units 32 . The upper thin film circuit layer 58 of the membrane switch circuit bo...

AI Technical Summary

Problems solved by technology

However, when the external atmospheric pressure changes, the design of the closed pre-space may lead to abnormal operation of the switch unit 32

like image 3 As shown, when the external air pressure decreases (for example, in a region with a high altitude), the air pressure in the preset space 28 is relatively higher than that of the external environment, which may cause the upper contact point 20 to be difficult to be activated by the key structure 16 (that is, press below)

And as Figure 4 As shown, when the external air pressure rises (such as being underwater or in an area with a low altitude), the air pressure in the preset space 28 is relatively lower than the external environment, so the upper contact point 20 may be pressed by the key structure 16 After that, it cannot bounce up, or the upper contact point 20 drops directly due to the high pressure outside, thus causing the switch unit 32 to operate abnormally.

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