×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Log In

Come Join Us!

Are you an
Engineering professional?
Join Eng-Tips Forums!
  • Talk With Other Members
  • Be Notified Of Responses
    To Your Posts
  • Keyword Search
  • One-Click Access To Your
    Favorite Forums
  • Automated Signatures
    On Your Posts
  • Best Of All, It's Free!
  • Students Click Here

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

Students Click Here

Jobs

Looking for opinions on rubber keypad vs rubber + membrane

Looking for opinions on rubber keypad vs rubber + membrane

Looking for opinions on rubber keypad vs rubber + membrane

(OP)
I am in a little argument over rubber keypad repair with an unreasonable person. I am looking for other opinions.

We currently repair a certain keypad that was manufactured with an obvious problem. The rubber pills are 3mm diameter and the circuit board contacts are a star inside a circle that is 6mm diameter so the conductive pill barely touches the outer ring. Picture

Any amount of oil or build-up will effect the buttons almost immediately and quickly make them impossible to use. As we know, most rubber keypads secrete oil (Source)

We use a membrane insert between the original rubber keypad and the circuit board. Our membrane has 7mm conductive contact area, blocks the oil the keypad produces and prevents the carbon pill from breaking down leaving the black residue behind.

From looking through keypad manufacturer's web sites, this seems to be the preferred method or at least an improvement over a rubber keypad alone.

Any other opinions out there?
Can anyone think of potential problems with this method? We have tested this extensively with countless machine controlled keypresses and even froze and heated the repair several times but it is nice to get input from others.
Thank You

RE: Looking for opinions on rubber keypad vs rubber + membrane

Won't the insert secrete the same oils as the original membrane?

Dan - Owner
http://www.Hi-TecDesigns.com

RE: Looking for opinions on rubber keypad vs rubber + membrane

(OP)
The original is a rubber keypad not a membrane. The membrane insert does not have oils and is made with plastic that will not allow the oils to penetrate.

RE: Looking for opinions on rubber keypad vs rubber + membrane

Check out GGI International's "Pushgate" switches.  I've been happy so far with their durability.

RE: Looking for opinions on rubber keypad vs rubber + membrane

The GGI Pushgate switches look very interesting but they will not work for my project. We are not designing this from scratch and the circuit board cannot be changed at this point.

We already have a solution that is working perfectly and I am not looking for another one. I would just like other's opinions on the rubber keypad & membrane combination. If anyone knows of anything that could go wrong etc...

Thanks

 

Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Reply To This Thread

Posting in the Eng-Tips forums is a member-only feature.

Click Here to join Eng-Tips and talk with other members!


Resources