Qualification of front foils at MOBA

by thain Blog, Crane & Lifteron Posted on

Qualification of front foils at MOBA

When selecting front foils for a wide variety of applications, MOBA takes great care to ensure the best quality. There are many front foil manufacturers, but not every front foil is suitable for the rough conditions for mobile applications in a construction environment. The differences in quality partly result from the composition of several different layers and materials.
There are different qualification stages that a front foil needs to pass in order to get to serial production:
  • 1. An endurance test
  • 2. A weather resistance test
  • 3. Salt spray test
Therefore, MOBA decided to implement test procedures along with the introduction of the front foil technology. Among other things, this resulted in the development and manufacture of a specially developed test stand for the qualifications of the front foils.

Front Foil Test Procedure

1. Endurance Test
The test procedure for a front foil is as follows: the front foil is applied to a printed circuit board and a keystroke is simulated with the aid of compressed air tappets. Using a PC, the keystrokes are documented, and the front foils are tested until the front foil is damaged.
2. Weather Resistance test
In the next qualification stage, the front foil is checked for its UV and form stability.

The front foil is tested in a sun simulation cabinet. The sun simulation cabinet can simulate temperatures and sun rays, as they can occur for example in the Arab countries. This test ensures that the front foil is dimensionally stable and that the dome embossing is retained. If the dome embossing is reduced by the heat, the worst-case scenario could be a self-triggering key.

In addition, this test checks that the colours are UV-stable and do not bleach out. However, the film is not only tested for heat, but also for its behaviour at minus temperatures. The film is exposed to extreme minus temperatures. The front foil goes through several of these cycles to reproduce reality as closely as possible.

3. Salt Spray Test
If the above tests have been successfully passed, the front foil must undergo a salt spray test. This test checks that no salt water can damage the front foil.

The front foil is also tested for its material resistance to a wide variety of substances such as lubricants, cleaning agents or operating fluids.

Only when all tests have been successfully passed does the front foil receive approval for use in production.

Even decor foils undergo the testing procedure

All of the so-called decor foils go through this testing process, too. This is a single-layer front foil with specific key symbols applied to a white front foil. This structure has proved to be very successful with the HMImc concept, as an HMI can be used on several different lifters and the specific key symbols are realised via the decor foil. This not only offers advantages in stock management due to identical parts, but also offers the possibility of replacing the decor foil at any time in the field if it is soiled by paint, etc. A front foil can also be changed at any time, but this must be done at MOBA’s.
Feel free to contact us for our HMI solutions and let us work together to develop your own HMI from proven components!

Post author

Written by