Are there buckling dome switches? Alternative to beam spring.

[cheater]

We have buckling springs and buckling beam springs, but are there buckling domes? Those hair clips (hair pins) describe the basic construction closely. They're made from two parts, one buckles and one doesn't. All you need is the part that buckles. I think they could feel pretty good.

The buckling part starts out as a single strip of metal, then a long hole is cut out in the middle. After that, it's essentially two long strips of metal, joined at the end, and they are still parallel. Next up, where they join, a pin is driven into the metal, embossing them. Those are the round depressions. That makes the two halves of the thing assume an angle compared to one another.

The nice thing here is that you only need one part for the spring, instead of two parts that have to precisely mate like they do with a beam spring, which saves on complexity. By changing the geometry of the buckling dome, you can modify the feel in significant fashion:
- width of strips
- angle between strips
- how deep the embossing is at the place where the two strips join
- how thick the metal is and what kind
- how long the metal strips are
- the shape of the strips (straight (before embossing), wavy, etc)

That's six parameters. It's a lot. I feel like you could easily find a lot of fun combinations this way.

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[ntv242ver2]

Wouldn’t fujitsu leaf spring clicky be close to what you are thinking here?

[Findecanor]

Metal dome switches would qualify, but all I've seen have been very low-profile switches: Most often microswitches and "tact" switches used for mouse buttons and gamepad buttons and such. Apple's "butterfly" scissor-switches are the only metal-dome switches I know of that have been put into a "keyboard" for a computer (... by some obviously sadistic person).

The Marquardt Butterfly seems to have a buckling leaf-spring, if I have understood this correcly:

I don't quite understand how the Futaba MA switch works, but I suspect it might work similarly. Someone with better knowledge better correct me if I'm wrong.

[Jan Pospisil]

Yeah, I think Futabas are exactly this. See Chyros explain it:
https://www.youtube.com/watch?v=6RCuy1JOqKI

[hellothere]

I think I now need to acquire a Marquardt keyboard ...

[hellothere]

Darn. Wiki says they were mostly used in typewriters.

[Chyros]

There are several designs that mimic this. The closest is clicky FLS3, which uses an actual buckling metal dome.

Apple's butterfly switches are also a (very very low profile) execution of the same principle.

MA are similar but it's not really a dome.

[cheater]

Thanks for the info. All those switches look cool, but none of them are to this idea what a model F or a beam spring is to buckling springs. The actual buckling element in all the switches mentioned is extremely tiny. Might be a time we built something bigger and with a much more pronounced tactile bump?