What is the earliest know rubber dome keyboard?

User avatar
snuci
Vintage computer guy

02 Feb 2017, 13:54

It's a simple question but I'm not so sure it's a simple answer. Was this technique brought on by the DIN standard and was, therefore, not used pre DIN?

I have an early Xerox computer that is from 1983 and I think this is the earliest I have.

Findecanor

02 Feb 2017, 15:43

Which DIN standard? "DIN" is the acronym for a standardization organisation.

codemonkeymike

02 Feb 2017, 16:17

It's called a DIN connector Findecanor. https://en.wikipedia.org/wiki/DIN_connector

User avatar
snuci
Vintage computer guy

02 Feb 2017, 17:07

Sorry, I was referring to this DIN standard: wiki/DIN_standard

User avatar
seebart
Offtopicthority Instigator

02 Feb 2017, 17:13

AFAIK rubber dome keyboards had nothing to do with any DIN standards, correct me if I'm wrong. jacobolus may know better, we had this "interesting" interaction before:

review-f45/the-alps-trilogy-part-1-appl ... t=standart

User avatar
Nuum

02 Feb 2017, 17:15

There is not just the DIN standard, there are many. The one in question is probably DIN 2137.
I also found DIN 42115 which apparently is about membrane keyboards.

User avatar
seebart
Offtopicthority Instigator

02 Feb 2017, 17:19

Nuum wrote: There is not just the DIN standard, there are many. The one in question is probably DIN 2137.
Correct. But DIN 2137 is just about layout Nuum, I think snuci means the "gerneral ergo computer standardization" from the 1980's whatever that one is called I forget.

User avatar
Nuum

02 Feb 2017, 17:30

Ok, you're probably right. Is EN ISO 9241 the right one?

User avatar
seebart
Offtopicthority Instigator

02 Feb 2017, 17:33

Nuum wrote: Ok, you're probably right. Is EN ISO 9241 the right one?
I have no idea and I don't have the patience to go through all those damn ISO docs now, you can find it in that discussion I had with jacobolus that I linked above!

User avatar
snuci
Vintage computer guy

02 Feb 2017, 18:19

I do agree, we should probably figure out the exact ISO number but I only mention this because I am guessing rubber dome came into play because of the switch height restrictions placed by this specification. Was there any, at all, rubber dome switches in the 1970's?

User avatar
seebart
Offtopicthority Instigator

02 Feb 2017, 18:27

snuci wrote: Was there any, at all, rubber dome switches in the 1970's?
I don't recall ever seeing one from 1970's. Here are two early examples, but I'm sure there are earlier ones:

wiki/IBM_RT_E57888

https://www.theregister.co.uk/2014/03/2 ... ese_years/

User avatar
Menuhin

02 Feb 2017, 18:43

May find this useful if you haven't read it yet.

http://imgur.com/a/P5sd8

User avatar
Daniel Beardsmore

02 Feb 2017, 19:02

snuci wrote: … I only mention this because I am guessing rubber dome came into play because of the switch height restrictions placed by this specification.
I don't see a reason to draw this conclusion. Switch manufacturers seemed perfectly capable of adapting switches to fit into a reduced profile (and in fact greatly surpass it). Curiously, one type that defied DIN standardisation for its entire life was Micro Switch SD Series. This is not because it was Hall effect: RAFI managed to create teensy Hall effect switches as early as the 70s (RS 76 C). I guess if you didn't want to sell to the Germans anyway, who cares?

The only problem with rubber is that it has a comparatively short lifetime. With rubber you get a switch that is smooth and quiet, which for many people is ideal. The problem is that the rubber changes characteristics over time, either stiffening, or losing its strength. There was some heated arguing a few years back about how well Topre rubber domes age, and I don't recall anyone ever coming to any conclusion. It's very hard to judge older rubber keyboards as you have no idea how they felt when new. The MEI T-15 switches I have feel awful, but when new they may have been much better.

These days, rubber domes give you several advantages: they are tactile, they're quiet, they're easy to assemble (all the domes in a single sheet of rubber), and they're cheap. Historically, rubber seems to have been used largely for cheapness, but also for tactility in non-contact systems. Whether it was specifically used for quietness, I don't know — maybe it was simply a good happenstance that you could make something that was both cheaper and quieter at once. Bargain!
snuci wrote: What is the earliest know rubber dome keyboard?
You already know my answer. Keyboard database.

Engicoder

02 Feb 2017, 20:13

I believe the rubber dome concept evolved from membrane switch technology which existed in the early 1970's. As such there really isn't a starting point for rubber dome keyboards...they are really just a long travel membrane switch of sorts. The first patent I have found that resembles what we now think of when as a "rubber dome" is from TI in 1980

"Long travel elastomer keyboard "
https://www.google.com/patents/US4354068

I know that when IBM Point of Sale Systems was developing the 4683 system in the early 80's they went with sealed conductive rubber dome over PCB to deal with the dirty environments they were used in. The dome technology IBM used was developed by SMK in Japan. Since the 4683 was released in 1983, I am sure SMK was developing the technology at least a few years before that.

User avatar
snuci
Vintage computer guy

03 Feb 2017, 02:09

These switches are pretty early and they are quite tactile which is odd. Here's the switches in my Xerox Sunrise. The keyboard is from Max-switch and is from 1983/84. More pics to come...
Xerox Sunrise - Maxi-switch discreet rubber dome
Xerox Sunrise - Maxi-switch discreet rubber dome
Xerox Sunrise - Maxi-switch discreet rubber dome.JPG (247.57 KiB) Viewed 6880 times

mr_a500

12 Jun 2017, 03:08

The earliest known rubber dome would have to be the Univac Uniscope 100 from 1969. I'm sure some of you remember when BobbyD, the designer of the Univac Uniscope 100 came to Deskthority and was kind enough to give us some blueprints and answer some questions. (thread)

Well, in the blueprints you can clearly see some large rubber domes (also confirmed by HaaTa's 1971 Uniscope 100 keyboard). BobbyD said that these new "switches" allowed for a very thin keyboard design and this was what distinguished the terminal from competitors.

mr_a500

15 Jun 2017, 21:32

Hmm... nobody cares?

What I'd be interested in is a timeline of all early switch types - when each company introduced what. Maybe somebody here has already done the research. (or maybe it already exists and I just don't know where to look for it)

I've done a bit of a half-assed listing (years ago) of early switch makers, but much is missing or unsure. Here's a (poorly formatted) pasting:

Code: Select all

Early keyboard switch makers:

Micro Switch - magnetic reed (196? - hall effect from ~1968, also clicky microswitches 196?)
George Risk - magnetic reed (1968?)
UNIVAC - rubber dome (1969), also 1970? clicky magnets (unknown if UNIVAC or other maker)
Controls Research Corp. - ? (1969?)
Control Devices - foam & foil? (1970?)
Hi-Tek - contact (1970?)
Key Tronic - magnetic reed (1970)
IBM - beam spring (1971 - previously used typewriter-like mechanics)
Clare Pendar - contact (1971?)
Cherry - contact (claims 1968, earliest seen 1973)
Datanetics - contact (1973?)
Licon/ITW - magnetic valve (1974?)
ALPS - magnetic reed (1975?)
Maxi Switch -  contact (1978?)
Mitsumi - rubber dome on stick (1978?)
Futaba - contact (1979?)

Early Terminals:

1963 TEK (possibly Micro Switch magnetic reed)
1964 Univac Uniscope 300 "Unimatic" (possibly Micro Switch magnetic reed)
1964 IBM 2260 (IBM typewriter-like mechanism)
196? IBM 2250 (IBM typewriter-like mechanism)
1967 Sanders 720 (Micro Switch magnetic reed)
1967 Burroughs Input and Display System (Micro Switch magnetic reed)
1968 RCA Video Data Terminal (George Risk magnetic reed)
1968 Datapoint 3300 (avail. 1969) (George Risk magnetic reed)
1969 Univac Uniscope 100 (Univac rubber dome)
1969 Alphacom (Controls Research Corp.)
1970 Hazeltine 2000 (Control Devices foam&foil)
1970 DEC VT05 (Control Devices foam&foil)
1970 Incoterm SPD (unknown magnetic reed?)
1971 IBM 3270 (beam spring)
1972 ADDS Envoy (Control Devices foam&foil)
1972 Beehive Model 1 (Micro Switch hall effect)
1973 ADM-1 (Controls Research Corp.)
1973 GTE IS 7800 (Licon/ITW?)
1973 Sycor 250 (unknown)
Last edited by mr_a500 on 16 Jun 2017, 02:30, edited 4 times in total.

User avatar
seebart
Offtopicthority Instigator

15 Jun 2017, 21:48

ALPS - magnetic reed (1975?)

:o I'd love to see those.

mr_a500

15 Jun 2017, 21:54

You don't remember HaaTa's "Super Alps"?

photos-f62/alps-cb14182b-scb1a163-aka-s ... t6525.html

Image

User avatar
seebart
Offtopicthority Instigator

15 Jun 2017, 21:56

Nope, that was just before I joined, no idea why I never found the link thanks.

Post Reply

Return to “Keyboards”