What are theses switches?

[gunnish]

Found these switches, they are linear. Any idea on what those are? Came from a cannon canola desktop calculator.

[Zeal]

http://home.vicnet.net.au/~wolff/calculators/Canon/Canon.htm

..."while the keyboard uses glass reed switches operated by magnets on the ends of the keystems"

The bottom of the PCB looked similar to hall-effect switches from first look. But the top isn't the same square ones I'm used to seeing. http://deskthority.net/wiki/Honeywell_Hall_Effect Perhaps a cannon variant?

But, dat thick plate!! 

[gunnish]

More specifically it is a canon canola bp1210-d,  I don't know when it was made, but one chip was made 1986 so not earlier that than.

[Daniel Beardsmore]

Ooo. The uncommon bar mount version of the Futaba complicated linear, in the bumblebee colour scheme. Not seen that variety yet.

[gunnish]

After reading the related parts of the wiki I have found out the following:
The keypad contains one "Futaba low-profile linear" for the TEST-button.
The switches has 4 pins, not 2 as in the wiki.
The two white switches found under the larger keys ("+" and "* =") are heavier than the black-orange ones.

[Daniel Beardsmore]

I've been wondering if the colour has any relationship with weight. Are they all white (slider, shell and base plug)?

Can we see some photos of these four-pin switches? I've never seen those before anywhere. I wonder what's inside them — possibly just a DPST for reliability, but even so, I don't know how you'd fit the parts in.

[gunnish]

Yes,  the two extra pins are probably just for stability.

There is always continuity between the two smaller pins. Between 71.50 g and 78.55 g of weight is required to actuate it.  for the black one it is between 57.59 g and 64.55 g.

Measured by adding coins on top of keycap while using a multimeter to look for continuity. Cap + coin weighted and the lowest weight for it to not actuate and the lowest for it to actuate was written down.

[Daniel Beardsmore]

You can take those apart safely by unscrewing the legs — what's inside of it?

[osi]

Magnets??

[dorkvader]

I've been wondering if the colour has any relationship with weight. Are they all white (slider, shell and base plug)?

Can we see some photos of these four-pin switches? I've never seen those before anywhere. I wonder what's inside them — possibly just a DPST for reliability, but even so, I don't know how you'd fit the parts in.

Some switches for PCB mounting have two extra pins, arranged in a diamond pattern. You can see an example of this in some of the Rockwell AIM keyboards that pop up on eBay from time to time.

I don't know why they would use them with a plate as well, but perhaps there was some sort of mechanical reliability standard they were wanting to achieve. Also, having two switched pins allows for easier trace routing.

As you can see, this switch uses a differnet pin layout.

There are also some reed switches that use more than two pins.

[Daniel Beardsmore]

*poke*