I have done 3 products over the years with membrane switches. I won't do
one again, they are not reliable enough.

I think the modern solution is non-moving switches, like elevator
controls, which last for 20+ years.

Microchip now makes a chip to handle these. The sensing mechanism is a
"capacitive switch". The sensing surface is normally glass, the back side
of the glass being conductive. The finger presses the front of the glass,
never touching the conductor. Installing the conductor pattern is very
inexpensive, just a layout and silver plating (like mirrors were done).

--Bob

>
>> Hi Guys,
>>
>> I am investigating the possibilty of having some membrane switches made
>> to
>> replace some 'expensive' ones that fail.
>>
>> They are pretty basic with only four switches, but they definitely need
>> to
>> be heavy duty ... and well sealed as they live in a pretty hostile
>> environment. (You dont have to look too closely on the attached image to
>> see
>> the female version of BS splattered all over them)
>>
>> Apart from being able to cope with high pressure hoses etc, they also
>> need
>> to be able to cope with heavy handed operators as well  ...  so
>> certainly
>> need to be heavy duty.
>>
>> What sort of numbers and prices and quality could I expect. Depending on
>> prices, I probably only need about 15 - 30 initially.
>>
>> Regards,   Roger
>>
>
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D
> Ruben J=F6nsson
> AB Liros Electronic
> Box 9124, 200 39 Malm=F6, Sweden
> TEL INT +46 40142078
> FAX INT +46 40947388
> ruben@pp.sbbs.se
> =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=
=3D=3D=3D=3D=3D=3D
>


-- =

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