Does anyone know what switch it is?
Full gallery here:
http://keep4u.ru/image/SYfrx
http://keep4u.ru/image/SYfrw
http://keep4u.ru/image/SYfrb
http://keep4u.ru/image/SYfr8
http://keep4u.ru/image/SYfrk
http://keep4u.ru/image/SYfrj
http://keep4u.ru/image/SYfrv
http://keep4u.ru/image/SYf0S
http://keep4u.ru/image/SYf0J
http://keep4u.ru/image/SYf0Z
Found on old trackball made by Disc Instruments, a.k.a. Honeywell, LX200, Danaher, Foxboro, Dynapar, etc. I've never seen anything like that: looks like hybrid of keyboard switch and a push button microswitch. Keycap is fixed by side axle; its pin is pushing the switch's coil spring directly. Travel is not downward, but merely like piano key. Switches are 4-pin; 1 pin is an actial contact and rest 3 are connected together internally. Very pleasant click feel BTW. All 3 switches are marked 8820: don't know if it's a type or manufacturing year/week (the device is really old). Googling brings this one as "8820", but it's totally irrelevant:
https://www.summitracing.com/parts/msd-8820
Probably, the switch is made by Honeywell (or one of its billion's sub-brands), but I'm not sure...
