Coil OVER dome key switch?

[snuci]

I recently acquired a vintage Sony M35 computer that I know nothing about (yet). Strangely enough, it has a mix of key switches (which is not normal, right?).

Sony M35 computer - computer unrestored

Sony M35 computer - computer unrestored - small.jpg (163.71 KiB) Viewed 1300 times

The Fx function keys are Omron B3G-S switches.

Sony M35 computer - Omron B3G-S

Sony M35 computer - Omron B3G-S - small.jpg (149.98 KiB) Viewed 1300 times

The interesting switch is the main keyboard keys that looks quite cheap and plasticy but the key switches actually felt prettygood. When I took a picture, I saw the internal spring below the key stem. Looks to be an internal coil but I would guess this is over dome?. Does anyone know what kind of key switch this might be?

Sony M35 computer - coil over dome

Sony M35 computer - coil over dome - small.jpg (164.28 KiB) Viewed 1300 times

This computer needs a serious cleaning and I'm not yet sure how to take it apart but that WILL happen shortly. Just wondering if anyone has seen these key switches before.

[ohaimark]

It's probably spring over membrane. Not sure what mechanism, though.

[snuci]

It's probably spring over membrane. Not sure what mechanism, though.

It may be hard to see from the picture but it looks like a conical spring because you can see the spring from the gaps in the sides of the key stem as well. Looks to be wide side up to narrow side down; sort of like an upside down Topre conical coil.

[ohaimark]

Topre and Prototopre keyboards are the devil's work; they simply feel to good according to some people.

SoDoM = Spring over Dome over Membrane = SIN!

On a more serious note, snuci is right. Looks coil-ish at second glance... Not sure if there's a dome though. Show us more!

[snuci]

Just to circle back, I posted pics at this thread: photos-f62/sony-m35-laptop-omron-key-sw ... ml#p286126

It's an Omron key switch spring over membrane.