DE20014172U1 - Keyboard for triggering electrical switching functions - Google Patents

Description

Keyboard for triggering electrical switching functions

The invention relates to a keyboard for triggering electrical switching functions according to the preamble of claim 1.

The so-called membrane keyboards combine an electrical switching function with great design options. These membrane keyboards have a control panel with switches that can be operated by finger pressure. The control panel is covered by a relatively thick plastic film. The design or decorative print is usually applied to the underside of the so-called front film. This has so far been done using complex, classic printing processes such as screen printing or offset printing, as only these printing processes have been able to meet the high quality requirements for the design. The disadvantage of these classic printing processes such as screen printing or offset printing is that they are very complex and therefore expensive.

Based on this, the invention is based on the object of creating a keyboard for triggering electrical switching functions of the type specified at the beginning with simplified printing.

The technical claim 1.

Solution is characterized by the features in the characteristic of the

Postbank Karlsruhe* (bank code account no. 37

The basic idea of the membrane keyboard according to the invention is to replace the expensive screen or offset printing of the film with a simple and therefore inexpensive paper print using a digital printing process. Instead of paper, a comparable, paper-like printing medium can also be used, which can contain, for example and in particular, plastic, for example a plastic coating, in order to achieve high print quality using digital printing processes using "special paper". The consistency, in particular the thickness of the paper-like printing medium should be comparable to the consistency of the paper, so that the same printing techniques can be used. The idea is therefore to print on paper or a similar standard medium, so that the resulting composite of front film and paper replaces the conventional front film, which previously had the decorative print on the back. This composite can be further processed like a conventional front film, for example it can be embossed, laminated to the circuit packages, etc.

As already mentioned, according to the development in claim 2, the paper or the like is printed using a digital printing process. The use of digital printing processes such as inkjet printing, thermal transfer printing, color laser printing, etc. has the advantage that a quality level of printing is achieved that is close to that of classic printing processes such as screen printing or offset printing. This creates an inexpensive and at the same time high-quality option for providing the front membranes of membrane keyboards with an appropriate design. In addition, these digital printing processes have the advantage of being very fast.

The further development according to claim 3 proposes that the plastic film is connected to the paper or the like over the entire surface.

Finally, a technical implementation according to claim 4 proposes that the paper or similar is laminated with its printed side onto the plastic film using an adhesive. This creates a technically simple process for creating the composite of paper and plastic film. The printed paper is permanently connected to the plastic film.

An embodiment of a keyboard according to the invention for triggering electrical switching functions is described with reference to the drawing. The drawing shows a purely schematic section of a keyboard in which the individual layers are separated from one another in a kind of exploded view.

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The keyboard initially shows - purely schematically indicated - a control panel 1 on which the switches that can be operated by finger pressure are arranged.

This control panel 1 with the electrical switches has a cover 2. This consists initially as the bottom layer of a paper 3, which is printed using a digital printing process such as inkjet printing, thermal transfer printing, color laser printing, etc. A plastic film 5 is laminated onto the printed side of this paper 3 using an adhesive 4, so that a solid bond is created between the paper 3 and the plastic film 5, which can be further processed like a conventional front film, for example by embossing or laminating onto the switch packages.

List of reference symbols

1 Control panel 2 cover 3 Paper 4 Glue 5 Plastic film

Claims (4)

1. Keyboard for triggering electrical switching functions
with switches arranged in a control panel ( 1 ) that can be operated by means of finger pressure, and
with a printed cover ( 2 ) comprising a plastic film ( 5 ),
characterized ,
that the cover ( 2 ) comprises a printed paper ( 3 ) or a comparable paper-like printing medium and
that the transparent plastic film ( 5 ) is connected to the paper ( 3 ) or the like to form a unit. 2. Keyboard according to the preceding claim, characterized in that the paper ( 3 ) or the like is printed by means of a digital printing process. 3. Keyboard according to one of the preceding claims, characterized in that the plastic film ( 5 ) is connected to the paper ( 3 ) or the like over the entire surface. 4. Keyboard according to one of the preceding claims, characterized in that the paper ( 3 ) or the like is laminated with its printed side to the plastic film ( 5 ) by means of an adhesive ( 4 ).