Scissor + low-profile BS keyswitch?!?!?

[bhtooefr]

http://patft.uspto.gov/netacgi/nph-Parser?patentnumber=5268545

Take a look at the images in there.

What really gets me is... I don't think they used it anywhere! The Model M6 and M6-1 use a complicated rubber dome setup, IIRC...

Unless they used in the PS/Note or something...

[Eclairz]

Me thinks by 1992, expensive keyboard were going out of fashion. Also Lexmark didn't exactly make keyboards for laptops which is where low profile would have been more popular.

Also buckling springs I hear are very forceful, not sure whether a scissor switch could keep taking the punishment without having a shorter key lifespan.

But the most realistic reason is probably cost and not enough demand.

But the thing is scissor are mainly used to keep the keys straight so the keys don't lean left or right, and spring bound keyboards are fairly rigid to begin with, so unless there was a smoother action or the scissors themselves were types of springs like current scissor keyboards today, with a very low force mechanical switch.

[bhtooefr]

Well, if you look at that patent, the scissors themselves were what acted on the buckling spring, rather than the key (like in a regular vertical BS keyboard.)

Anyway, Lexmark DID make some laptop keyboards - although IBM eventually switched to KeyTronic, the earliest Model M6s (for ThinkPads) were made by Lexmark.

[Eclairz]

I guess lexmark were developing new keyboards for the laptop market until cheapo laptops became the norm. Either way its a unique way to mechanise the keyboard, using the spring widthwise rather than heightwise.
It does look extremely fiddly to implement and scissor switches are already quite fiddly, this is just more so. If i were to redevelop the switch for today you would need to simplify it, like the spring only controls one arm of the scissor not both, while the other just adds stabilisation for the key.