Membrane switch

[evans_us]

Hi
Anyone know where I can get an off-the-shelf membrane switch. I need 4 buttons (Up/down/enter/reset). If it helps these will be going to the right of a 4x20 LCD display. Thanks for suggestions in advance
Evans_us

 

[kevrus]

Here is a bezel from Rapid Electronics but only has 3 switches and is quite pricey...
http://www.rapidonline.com/Electronic-Components/Switches/Keypads/Display-bezel/72867

Just an idea as I don't know your application, ive used 12mm x12mm PCB mounted switches with the board epoxied to the front panel and just round buttons showing through.

 

[slurp]

I've looked at a number of switches recently (not membrane) that where found via searches for joystick and navigation.

http://uk.farnell.com/multicomp/mcpl3-bc-v/navigation-switch-3way-smd/dp/1316993

http://uk.farnell.com/multicomp/mctt5-v/navigation-switch-5way-micro-smd/dp/1316988

http://uk.rs-online.com/web/search/searchBrowseAction.html?method=getProduct&R=0516031

I hope these help you to your solution... the alternative is to arrange a number of indivial switches on your enclosure with some printed or engraved legend.

Best regards,
Colin

 

[papaof2]

Try Ebay. A 4 button switch from a Tecra laptop is $12US shipped to US:
http://cgi.ebay.com/TOSHIBA-TECRA-8200-INTERFACE-MEMBRANE-SWITCH-UE2011P04_W0QQitemZ150265054419QQcmdZViewItemQQptZLH_DefaultDomain_0?_trksid=p3286.m20.l1116

You might salvage the keyboard from a cell phone or calculator. Goldmine Electronics has a Sony/Ericson phone with 5 buttons at the top (plus the numeric keys) for $7US plus shipping http://www.goldmine-elec-products.com/prodinfo.asp?number=G15616 - the display would be a bonus for a future project ;-)

John

 

[evans_us]

Thanks for suggestions

Hi All
Thanks for the responses - I will need a ready supply of the switches for the final product. I am using the tactile buttons inserted through the front panel and these work well but I really need the membrane switches to provide that "professional look". Ideally a diamond pattern (the way I have my buttons now with up/down top and bottom and back/enter left and right would be the best solution. I really liked the nav button idea but am afraid that misspressed buttons could mess with the outcome for the end user.
I see these on instruments all the time so someone must have made these - I just don't want to go the custom route.
Thanks again

 

[Dippy]

I have used Membrane switches and I like the way you can slip your pre-printed legend into it to make it look good and readable. Though, unless you machine a recess, the membrane switch isn't exactly flush. (sorry, thats being a bit over-pernickety).

I prefer the may some pukka manufs do it . Your front plastic panel has a "U" (well sort of) machnined through it. This makes a flexible flap. Then your tacticle switch goes behind and a printed vinyl sticker goes over the front. This flap means the visible 'press switch' is flush and provides a bit of springyness for the return stroke.
Anyway, maybe a litte OTT for a one-off but there we are.

And, with the possible exception of Grim-Bay, I've always found the prices of membrane switches a bit steep for what they are.

 

[slurp]

I really liked the nav button idea but am afraid that misspressed buttons could mess with the outcome for the end user.

May be this is a better option, it a bit more expensive tho'

http://uk.farnell.com/mec/9509136118/switch-module-black/dp/1390595

best regards,
colin

 

[gengis]

I can describe what we used for some "chemist-proof" switches on a heated water bath circulator. Chemists can screw most anything up and a lab is a harsh environment . . .

The case was custom fabricated thin stainless steel and we needed a window to see the display and set of four pushbuttons to set time and temperature. The switches were the small tactile buttons you see used on PC boards. We mounted them to perf board along with the display and mounted the whole sub assy. to a cut-out in the SS case.

For the membrane, we found a sign manufacturer. They specialized in these self adhesive, lettered, custom, designed for any application, and cut into vinyl by a computer driven stylus (knife) on a large X/Y plotter. The machine can make signs for the sides of trucks - but can also do very fine work. The vinyl comes in colors and clear and we used three layers to build up the window and lettering. The two base layers were the background color and lettering (about as thin as coat of paint) and the top layer was a thick clear vinyl.

We only had to make twelve of the things but the lab was a show place intended to 'wow' prospective clients so everything had to look state of the art. The only tricky parts were the registration (alignment) and getting the air bubbles out between layers. We laid the whole thing down on some thick glass initially, then heated the glass and peeled up all the layers and transferred them to the front panel.

It looked pretty good and withstood the water and weak hydrochloric acid they were using.

 

[slurp]

This sound good, I think I could make a budget version with printed paper layout and the low cost liminator - a bit of double sided sticky tape of glue and it can be fitted to an enclosure.

I don't have an application but I'm certainly going to remember this for a home brew solution

regards,
colin

 

[PhilipS]

Here is someone who used a laminator to create a front panel.

http://picprojects.org.uk/projects/chc/chprgrammer.htm#Construction