Unknown dome with slider?

[keycap]

So I just found a typewriter earlier today and it uses these strange conductive dome with sliders, personally I've never seen them before. Build quality of the keyboard itself is pretty bad, but the keyfeel is decent. Feels like a more-tactile MX Clear switch. Has anyone seen these before? The keycap mount oddly resembles Topre.



I apologize for the poor image quality, like I said I just received this typewriter. I would like to know who makes this switch though. The typewriter itself is a Brother GX-6750.

[emdude]

I think many of these Brother typewriters have similar or identical mounts, and at least some of them seem to be Topre-compatible, albeit with off-profiles and such.

From a quick search:
https://geekhack.org/index.php?topic=64072.0
https://geekhack.org/index.php?topic=46009.0

[keycap]

Olivetti dome with sliders had a very similar diagonal arm structure on the bottom left and top right corners. Maybe this is something from Olivetti?

[Chyros]

Brother dome and foil, aka Prototopre.

[keycap]

Huh, seems like an entirely different switch compared to Brother dome and foil. It's just a slider over a conductive rubber dome.

[Chyros]

Can you post a picture of the dome mat and what's under it? The slider definitely looks identical to Brother dome and foil.

[keycap]

Sure thing.

Spoiler:

To me, they look much different. Not sure if it's visible in the image, but there is conductive material under the dome, similar to BTC dome with sliders.

[Chyros]

There's foil under the domes with dome and foil, but you're right, this appears to not be it. Looks like it's the dome with slider successor to Brother dome and foil, and they just kept using the same mount, that's why it looks the same from the outside.

[keycap]

These are some very new dome with sliders, too. According to the sticker on the assembly, it was manufactured only three years ago. I didn't think that dome with sliders were still being made in this decade, set aside Topre and all of those mediocre, gaming-oriented "half-mechanical" plunger switches.

[Findecanor]

They feel close to Cherry MX Clear, huh? Is the plastic slider acting as a leaf-spring at the lower half of travel?

BTW, I googled other pictures of the typewriter, and I like how the bottom-row keys are in almost space bar profile and the Return key is an upside-down "Big-Ass" key.