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by userbinator
2896 days ago
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The fact that the membrane is still vented (labeled 321 in the diagram) suggests that this will only delay, and not fix the dust ingress problem. Indeed, it could make things worse by creating a tiny pump[1] that draws particles in on each keystroke. I don't know why they didn't vent from the bottom instead, but that's how completely sealed (i.e. waterproof) keypads are vented. [1] https://en.wikipedia.org/wiki/Diaphragm_pump Edit: wow, downvotes? Care to explain...? |
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> [0058] For example, FIG. 3D depicts a third alternative example of the key assembly of FIG. 3A. In this example, the membrane 213 or gasket defines a vent 320, aperture, or other hole in one of the sides 318A. When the key cap 103 is moved towards a depressed position, the membrane 213 compresses gas inside the internal area 319, forcing the gas through the vent 320. This allows the embossed area of the membrane 213 to act as a bellows mechanism, forcing gas in a direction 321. This may force contaminants away from the internal area 319 and/or out of the aperture 210. This may also reduce compression of the membrane 213, reduc- ing how much the membrane 213 affects the force curve response.
The specific point about sizing is this next section:
> In various implementations, the vent 320 may be configured with sufficiently small dimensions that gas can be forced through the vent 320 without easily allowing liquids, dust, and/or other particles to enter the internal area 319 from the aperture 210.
Also here's the Patently Apple analysis [0], which points out that this patent covers three different designs (the vented one being the third). I'm not sure the third design we're discussing is the one implemented in the 2018 models though.
[0] http://www.patentlyapple.com/patently-apple/2018/03/a-new-ap...