Membrane switches – customized

We realize customer-specific membrane switch and advise you comprehensively on equipment requirements and technical features.

Folientastatur

Due to the extraordinary variety of design options, membrane switches are used in almost every type of electronic device. The ergonomic and design requirements are nearly unlimited.

Membrane switches are dirt and water resistance. They are used when a compact design is needed or a small number of units are desired because of comparatively low tooling costs.

You can choose from a variety of constructions of varying tactility and a wide range of viewing windows, screens and lighting options. In addition, we offer the patented Duraswitch technology.

Advantages

  • low weight, space saving
  • backprinting of the film for a robust, individual design
  • individual tactility
  • dustproof and water resistant, resistant to chemicals (solvents)
  • easy to clean
  • over 1 million life-time cycles
  • EMC shielding possible
Construction

Construciton

Aufbau einer Folientastatur
Aufbau einer Folientastatur

A keypad consisting of a plurality of individual layers which are superposed on each other.  By default, there is a membrane keyboard from 5 basic foils: decorative foil, upper & lower switching foil,  a spacer film and a adhesive foil.

The decorative foil is made of polyester or polycarbonate and ensures the highest possible protection against abrasion. For applications in the medical field and areas with high hygienic requirements, the front foil can be equipped with an antibacterial coating. Also UV-resistant polyester for outdoor use is possible.

Functional elements are the lower circuit foil with the conductor tracks, switching points and the terminal lug located thereon, as well as the upper switching foil with the contact surfaces which lie opposite the switching points on the lower foil. The upper switching foil can be dispensed if it is replaced by metal domes, or the contact surfaces are printed directly on the decorative foil.

For special applications and complex circuits, the lower switching foil is made of polyimide (Kapton) instead of polyester. A hard printed circuit board made of FR4 is suitable for circuit design and at the same time acts as a carrier plate with mounting screws or sockets. The spacer foil as an insulator separates the upper and lower switching foil; in a version with metal domes, it has the task of fixing foil.

Tactility

Tactility

Metal dome


For a striking tactility and higher actuation force metal domes can be used. When the metal dome is actuated, it snaps downwards and establishes contact between two printed conductors.

 

Embossing


Membrane switches without metal domes may also have tactile feedback using dome embossing design. The dome embossing can be done in the decorative film as well as in the upper switching film. For a stronger operating force and tactility, even both of the two films can be shaped.

  • Dome embossing: This embossing is not only suitable for round, but also for square buttons.
  • Terrace embossing: The entire button surface is raised. This embossing is usually used for small buttons.
  • Frame embossing: A raised edge is formed around the key surface.

 

NH Folientastatur Muster
The N&H sample membrane switch will be sent to you on request.
Options

Options

Equipment Options

 

LED’s


LEDs can be easily integrated into membrane keyboards by the integration of an additional LED switching foil. Special adhesives and sealing materials are used to control the function of the LED even in a harsher environment with e.g. ensure strong vibration.

 

Light Guide Film (LGF), also with disappearance effect


Folientastatur mit LGF Hinterleuchtung
Membrane Switch with LGF

Backlighting of membrane switch can be done by using LGF (Light Guide Film). The typical flat design and flexibility are retained. In the LGF technology, LEDs are used on the edge in a very thin (0.1 – 0.2 mm), highly refractive film. Due to the high refraction of light only very few LEDs are required for homogeneous illumination. The backlighting of each button can be done in different colors.

Also with the LGF technology a “disappearance effect” can be realized. The keyboard symbols are only visible when the HMI device is switched on.

Verschwinde-Effekt
Membrane switch with integrated touch panel and disappearance Effect

 

Membrane switch with integrated touch panel


An integrated touch panel creates a combined input system that considerably simplifies and sensibly complements the application control.

 

Folientastatur mit Drehgeber und Sichtfenster
Membrane Switch with integated windows and rotary encoder

 

Membrane Switch with integated windows


Depending on the requirements and optical design, it is possible to specify versions such as glossy, matt, anti-reflective, scratch-resistant, UV-resistant and colored for the viewing windows of the LCD and LED.

 

Duraswitch Technology


The Duraswitch © technology enables the integration of push buttons with tactile feedback, rotary encoders (rotary encoders and analog potentiometers) and cursor controls. Compared to separate solutions, the integrated solution is much more cost-effective.

 

Metal plate


For reinforcement, the membrane keyboard can be mounted on various carrier plates. As standard, aluminum plates may be used with fastening bolts.

 

Protection


  • EMC protection: All keyboards can be provided with appropriately printed masks to comply with the requirements for electromagnetic shielding.
  • IP ratings: To ensure use in extreme environments that are dust or water intensive, IP65 rated protection is required.
Design

Design

Folientastatur mit Silikonabdeckung und Epoxy Coating
Membrane switch with silicone keys / rubber design and Epoxy Coating

 

Membrane switch with silicone keys / rubber design


The membrane switch is as usual provided with a polyester decorative film, but the buttons are made of silicone. The keys have a grippy key surface, which gives the feeling of a high-quality keyboard. The key shape can be realized in various geometries. Alternatively, the decorative film is completely replaced by a silicone layer. This allows for outstanding buttons with free shaping, guide elements such as offset rings around a key, Braille lettering or cursor keys. At the same time, the surface is upgraded visually and haptically.
 

Folientastatur mit Hochglanzoberfläche im Vergleich zu Matt
Membrane Switch with glossy and mat surface finish

 

Membrane Switch with epoxy coating


High-quality three-dimensional design elements can be realized with epoxy. Instead of a “normal” embossing, epoxy material is applied to the button, which creates a particularly high-quality and glossy surface due to its transparency. The epoxy design can be used with most membrane keyboards.
 

Membrane Switch in metal design


Metalleffekt Folientastatur

Specially embossed films can be used to achieve metal-optic effects, such as brushed stainless steel or anodised aluminum.

References

References

 

Suitable housing, cable assembly, display?

In addition to the membrane keyboard as an input element, we also supply suitable housings, cable assembly, and the pcb , etc. – True to our guideline – single source supply !

Muster von kundenspezifischen Folientastaturen
Muster von kundenspezifischen Folientastaturen