Industry:
Non Tactile Switch Activation
Application:
Wire Assembly with Epoxy Coating
Opportunity:
Combine an existing PCB with an existing molded assembly, utilizing a metal dome for a tactile switch. The switch had to be activated by the edge of the PCB instead of a fingertip and the unit had to withstand 100% humidity and extreme heat for 10 days. Not only did the unit have to successfully withstand extreme heat and humidity, but also hold up during a four foot drop test.
Solution:
First, we had to devise a way to fully enclose the switch so that the humidity could not penetrate. At the same time, an escape route for the compressed air during switch activation was needed. We managed to accomplish consistent, reliable results with a combination of polyimide tape precisely cut and aligned with protective oil. Next, we used a combination of epoxy and protective oil to protect the exposed surfaces. Finally, the snap dome was to be activated by the edge of a PCB, which is an atypical usage. We modified the metal dome switch so that it did not have its contact point fully encased in the diameter of the switch. By making this modification, we were able to accomplish multiple activations without false or missed contacts.
Result:
Because of the thoughtful selection of materials and “out of box” thinking in design, Flexible Circuit was able to create a device that met the heat, humidity and drop tests required by our customer.
