DE102012013831B4 - LED board - Google Patents

Abstract

LED board (1) with a sandwich-like structure for the flexible, stuttering arrangement of LEDs (6) of different texture and colors, characterized in that this sandwich structure consists of two outer insulating layers (2) which are interconnected optionally by a) two carrier-based Adhesive tapes coated with double-sided pressure-sensitive adhesive, each containing an electrically conductive adhesive layer (3), a conductor foil (4) and an electrically non-conductive adhesive bonding layer (5) with an insulating layer (2) between the two double-sided pressure-sensitive adhesive tapes, wherein the double-sided adhesive-coated adhesive tapes and the insulating layers (2) are arranged so that the electrically non-conductive bonding adhesive layer (5) of the first double-sided pressure-sensitive adhesive tape applied to the first outer insulating layer (2) and that the conductive adhesive layer (3) d it adheres to the second outer insulating layer (2) second double-sided pressure-sensitive adhesive tape orb) a laminated adhesive composite of four layers, each having two electrically non-conductive, also the function of an insulating layer (2) with fulfilling adhesive layers (5), and two electrically conductive, also the function of a conductor foil (4) with fulfilling adhesive layers (3), are alternately connected to each other orc) a combination of two carrier-based, one-sided pressure-sensitive adhesive tapes, each comprising a conductor foil (4) and an electrically conductive adhesive layer (3) in which on the one hand an insulating layer (2) has been applied to the electrically conductive adhesive layer (3) of the first single-sided pressure-sensitive adhesive tape and on the other hand a layer of an electrically non-conductive connecting adhesive (5) this insulating layer (2) with the conductor foil (4) the second n, one-sided pressure-sensitive adhesive tape connects.

Description

It is in the present invention to be produced in a simple manner LED lighting boards for decoration and / or information purposes on a freely selectable surface that allow a completely flexible distribution and rapid replacement of the LEDs on the board regardless of sockets, plugs and cables.

"Light emitting diodes", short LEDs or light emitting diodes, are relatively simple: They consist essentially of four components, namely the LED chip, a reflector with contact to the cathode, a gold wire as contact with the anode and a plastic lens, the other Components united and fixed in themselves. The anode and cathode are usually designed as pins or pins of the same length, which are plugged into a socket and thus produce the necessary contact with the voltage source for illumination.

LEDs are made of semiconductor devices that form a diode that allows current to flow in one direction only, converting the electrical energy into light. If current flows through the diode in the forward direction, electrons migrate from the n-doped to the p-doped side and emit light, infrared radiation or ultraviolet radiation with a wavelength dependent on the semiconductor material and the doping; the electrons give their energy in the form of a flash of light free. Since the p-layer is very thin, the light can escape. Even at low currents, a light emission is perceptible. The light intensity increases proportionally with the current.

There are LEDs in different colors, sizes and designs. Therefore, they are increasingly used as a signal and light source for a variety of purposes.

The light-emitting diode switches very quickly from the luminous to the non-luminous state. Like any other diode, the LED is polarity dependent. One connection side is the anode, the other side is the cathode.

LEDs are very sensitive to excessive forward current. Therefore, a light emitting diode must never be connected directly to a voltage. A light-emitting diode must always be operated with a series resistor or a current-limiting component. With a series resistor, the forward current flowing through the LED is limited. When determining the resistance, the respective forward voltage must be taken into account. A light-emitting diode already burns at a fraction of the maximum forward current. In addition, light-emitting diodes do not necessarily have to radiate their full luminosity. Usually only a few mA are enough to produce sufficient brightness.

Unlike light bulbs, light emitting diodes are not thermal radiators. They emit light in a limited spectral range, the light is almost monochromatic. Therefore, when used as a signal light, they are particularly efficient compared to other light sources where color filters must absorb most of the spectrum to achieve a monochrome color characteristic. LEDs contain no mercury, have a lower energy requirement in operation, give off little heat, which is why no lampholders are required, they are highly shock and vibration resistant, they are virtually inertia-free switchable and cause relatively low disposal costs. All these features make LEDs an increasingly popular light source.

From the patent and other literature as well as from everyday life many applications of LEDs are known. In the vast majority of these applications, in contrast to the LED board according to the invention, the LEDs are connected to a corresponding socket and directly via appropriate cables or cables with a power source and therefore less flexible in their applications. In the case of the present LED board, however, a completely flexible distribution of the illumination is possible, the board can e.g. be a lit blackboard with a map or escape route plan as a surface.

This is made possible by two significant features of the invention, namely on the one hand, the specific layered structure of the board using electrically conductive pressure-sensitive adhesive tapes and the modification of the LED pins.

Similar systems are already claimed in the patent literature, in particular in US 2009/0 201 680 A1 in which a layered structure of the board and modifications of LED pins for the production of a board are described in principle the same functions as in the present invention here board. Other such systems are described in CN 201215292 Y, CN 201383612 Y, CN 201706251 U and WO 2010/121532 A1 presented. However, in none of these publications are electrically conductive adhesive layers or even electrically conductive adhesive tapes considered as part of the boards, but as conductive layers explicitly metal nets, aluminum foils or electrically conductive textiles are listed. LED boards with layer construction are also off WO 88/09 984 A1 . DE 697 11 642 T2 . WO 2007/006 147 A1 and EP 2 037 723 A2 known.

The present invention board ( 1 ) is explained in more detail below with reference to the two accompanying figures. E consists of at least 3 Isolation ( 2 ) and 2 Conductor layers ( 3 ) arranged in the following order: insulation layer ( 2 ) - conductor layer ( 3 ) - Insulation layer ( 2 ) - conductor layer ( 3 ) - Insulation layer ( 2 ). Depending on the nature of the material used as a conductor layer, additional layers in the form of a bonding adhesive ( 5 ) and a conductor foil ( 4 ) may be contained in the layered structure. For the two conductor layers ( 3 ) one is used as a phase layer and one as a neutral conductor layer. These two types of layers are connected via lines directly to the poles of a battery, which serves as a voltage source. Non-conductive insulation layers ( 2 ) may be, for example, foam, rubber or even a combination thereof. The actual LEDs ( 6 ) are modified insofar as one of the two pins of an LED, namely the negative pole is shortened in such a way that it extends only into the first conductive layer. At the same time, a part of the other pin, the positive pole, which emerges from the LED housing, is pressed against the first conductive layers of electrically conductive adhesive ( 3 ) and conductor foil ( 4 ) insulating sheath attached to prevent a short circuit. For LEDs with more than two pins, all pins except the one into the first conductive layer ( 3 ) reaching pins are partially provided with such an insulating sheath. Now, if such a modified LED is applied to a board of the type described, it lights up.

Similarly, LEDs with only one pin can be used, such as in US 20090201680 A1 be characterized as a "second type LED", in which the pin alternately consists of conductive and insulated sections, the order of the conductive ( 3 . 4 ) and non-conductive layers ( 2 . 5 ), in which the pin is inserted, corresponds.

Accordingly, a board according to the invention has, for example, the following layer structure: a styrofoam base plate or another carrier material which is electrically insulating ( 2 ), by means of a bonding adhesive ( 5 ) a positive-pole conductor layer ( 4 ), for example, applied an aluminum or copper foil. On this aluminum or copper foil is an electrically conductive adhesive ( 3 ) applied. In a preferred case, the last two layers ( 3 . 4 ) formed by "DuploMED ® 858" a one-sided adhesive electrically conductive adhesive tape of the company "Lohmann GmbH & Co. KG". This consists of an electrically conductive acrylate copolymer adhesive ( 3 ) with an aluminum-polyester composite film carrier ( 4 ) and is commonly used to attach electrodes to the body. On the electrically conductive adhesive layer ( 3 ) an insulation layer ( 2 ) is applied, for example, from polystyrene as the next layer in the sandwich construction, followed by another bonding layer ( 5 ), with which finally a renewed and in this case acting as a negative pole conductor layer ( 4 ), which again may be an aluminum or copper foil, is fastened. With the help of another layer of a conductive adhesive ( 5 ) is then applied again an insulation layer, for example in the form of a poster, a geographical map, a map or the like. The adhesive layer (below this insulation layer) 3 ) as well as the underlying conductor layer ( 4 ) can in turn be formed by a correspondingly shaped adhesive tape, for example, again from the above "DuploMED ® 858". Will now be a modified as described above LED ( 6 ) with pins designed according to the requirements of the sketched sandwich construction of the board in this board, the LED lights ( 6 ) on. Because the two conductive adhesive layers ( 3 ) over the whole board ( 1 ) is used to illuminate the board ( 1 ) or individual segments thereof the distribution of the LEDs 6 ) on the board ( 1 ) as completely variable as the color scheme of the whole is completely free. The respective bonding adhesive ( 5 ) in such a system may be both a carrierless adhesive tape and a liquid adhesive.

As an alternative to the above-mentioned pressure-sensitive adhesive tape, the use of "DuploCOLL® 181 EC", an applicant's electrically conductive, carrier-free transfer adhesive tape with a pure acrylate adhesive, is conceivable at the locations where an electrically conductive adhesive layer is provided in the system. The advantage of using such a transfer belt is that it eliminates the use of a special conductor foil and thus a material and thus cost savings is effected.

A board according to the invention particularly preferably has the following layer structure: on an insulating base plate ( 2 ) is a double-sided pressure-sensitive adhesive tape with a conductive aluminum or copper carrier material ( 4 ), the adhesive layer towards the base plate ( 2 ), a non-conductive adhesive ( 5 ) and the opposite adhesive layer ( 3 ) be a conductive adhesive. On this conductive adhesive layer ( 3 ) is again an insulating plate ( 2 ), on this in turn a double-sided pressure-sensitive adhesive tape again with a conductive aluminum or copper carrier material ( 4 ), a non-conductive adhesive layer ( 5 ) to the plate and an opposite conductive adhesive layer ( 3 ). The latter is then replaced by LEDs ( 6 ) to be populated cover as insulation layer ( 2 ) glued, which then, for example, again have the above functions.

The following structure of the board is particularly preferred: On an insulating base plate ( 2 ) is applied to a laminated carrierless adhesive tape of four layers in the following order: on a non-conductive adhesive layer ( 5 ) is a conductive adhesive layer ( 3 ) concealing the function of the aluminum or Kupferleitfolie ( 4 ) from the examples before with. In addition, a non-conductive adhesive layer is laminated ( 5 ), which also provides the insulation function of the isolation plate (see FIG. 2 ). Finally, a conductive adhesive layer follows ( 3 ), which again here the function of the aluminum or Kupferleitfolie ( 4 ) with takes over. This conductive adhesive layer is finally covered by LEDs ( 6 ) to be populated cover as insulation layer ( 2 ) applied. In addition to acrylate adhesives, other suitable and well-known adhesives, for example based on rubber or silicone, can of course also be used throughout the system both as electrically conductive adhesives and as bonding adhesives.

The current applied to each conductive layer may vary depending on the layer, it may even vary with any subdivisions within such layer.

LIST OF REFERENCE NUMBERS

1

LED board

2

insulation layer

3

Conductive adhesive

4

conductor film

5

bonding adhesive 6 LED

Claims (4)

LED board (1) with a sandwich-type construction for flexible, stuttering arrangement of LEDs (6) of different texture and colors, characterized in that this sandwich-like structure consists of two outer insulating layers (2) which are interconnected optionally by a) two carrier-based, double-sided pressure-sensitive adhesive tapes, each containing an electrically conductive adhesive layer (3), a conductor foil (4) and an electrically non-conductive bonding adhesive layer (5) with an insulating layer (2) between the two double-sided pressure-sensitive adhesive tapes, wherein the Double-sided pressure-sensitive adhesive tapes and the insulating layers (2) are arranged so that the electrically non-conductive bonding adhesive layer (5) of the first double-sided pressure-sensitive adhesive tape applied to the first outer insulating layer (2) and that the conductive adhesive layer (3) b) is a laminated carrierless adhesive composite of four layers, in each of which two electrically nonconductive, also the function of an insulating layer (2) with fulfilling adhesive layers (5), and two electrically conductive, even the function of a conductor foil (4) with fulfilling adhesive layers (3) are connected to each other alternately or c) a combination of two carrier-based, one-sided pressure-sensitive adhesive tapes, each having a conductor foil (4) and an electrically conductive adhesive layer ( 3), wherein on the one hand an insulating layer (2) has been applied to the electrically conductive adhesive layer (3) of the first single-sided pressure-sensitive adhesive tape and on the other hand a layer of an electrically non-conductive connecting adhesive (5) this insulating layer (2) with the conductor foil (5) 4) of the zw the adhesive, one-sided pressure-sensitive adhesive tape. LED board (1) according to Claim 1 , characterized in that when using carrier-based pressure-sensitive adhesive tapes, the carrier is in each case an aluminum or copper foil and thus simultaneously acts as a conductor foil (4). LED board (1) according to Claim 1 , characterized in that two simultaneously serving as Leitfolien and one side once with an electrically conductive (3) and once with an electrically non-conductive adhesive (5) coated carrier materials (4) are interconnected by means of a carrier-based double-sided adhesive tape whose one side electrically conductive adhesive (3) and the other side is electrically non-conductive adhesive (5) is equipped and forms its electrically non-conductive carrier material located in the middle of the sandwich insulating layer (2). LED board (1) according to one of the preceding claims, characterized in that each conductive layer (3) is subdivided into different, mutually independent and each to be supplied by its own power source sections.

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