NL2008543C2 - LED LIGHTING, LIGHTING COMPOSITION, HOUSING, MATERIAL AND USE, AND METHOD FOR THIS. - Google Patents

Description

LED LIGHTING, LIGHTING COMPOSITION, HOUSING, MATERIAL AND USE, AND METHOD FOR THIS

The present invention relates to an LED lighting.

5 LED lighting comprises one or more LEDs, such as conventional LEDs, OLEDS (organic LEDs) or Pleds (polymer LEDs).

Various LED lights are known from practice.

One of the problems with conventional LED lighting 10 is that a heat sink must be provided to dissipate the heat from the LEDs. Such a heat sink is often made of aluminum. The heat sink takes up a certain space, makes production of the lighting complex and detracts from the appearance of the lighting. Moreover, a heat sink blocks part of the light.

An object of the invention is to eliminate or at least reduce the abovementioned problems and to provide an LED lighting in which heat is effectively removed.

The LED lighting according to the invention comprises: - a housing; - at least one LED mounted in or on the housing; and at least one contact point electrically connected to the at least one led, wherein the housing is at least partly made of a light-transmitting and heat-conducting material, such that the housing, in use, dissipates the heat produced by the at least one led 30.

In the context of the invention, "led" is understood to mean oled or pled in addition to conventional led.

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Translucent means in the context of the invention that at least part of the visible light is transmitted.

The housing is, for example, an enclosure which is for instance largely closed, or an open housing.

By manufacturing the housing at least partially from a light-transmitting and heat-conducting material, a separate heat sink can be dispensed with. After all, the housing functions as a heat sink, or at least as a heat sink.

10 This simplifies the production of the LED lighting. Moreover, it is prevented that the part of the housing that transmits heat blocks light. This increases the efficiency of the LED lighting. Moreover, the lighting radiates light in all directions. The improved heat transfer also increases the service life of the at least one LED.

For example, the housing is made entirely or at least for the most part from such a material.

Preferably, the at least one LED is mounted on the housing 20 or the LED is located near the housing, such that the LED effectively transfers its heat to the housing. For example, the at least one LED is attached to an inner wall of a hollow housing or the LED is in the material of the housing.

Preferably, the thermal conductivity of the light-transmitting and heat-conducting material is greater than 10 W nf1 KT1, preferably greater than 50 W nf1 KT1, even more preferably greater than 100 W nf1 KT1, even more preferably greater than 200 W nf1 K_1 and most preferably greater than 300 3 0 W m ”1 PT1.

For example, the thermal conductivity of the material is 221 W nf1 K-1. Such a thermal conductivity is many times greater than the thermal conductivity of known light-transmitting materials, such as glass or light-transmitting plastics. At the same time, the thermal conductivity is preferably comparable to the thermal conductivity of non-light-transmitting materials that serve as cooling in conventional lighting, such as aluminum.

In a preferred embodiment, the transmission of the light-transmitting and heat-conducting material is greater than or equal to 60%, preferably greater than or equal to 75%, more preferably greater than or equal to 90%.

In a preferred embodiment, the light-transmitting and heat-conducting material comprises a mixture, which mixture comprises a continuous phase of a light-transmitting material and a dispersed phase of a heat-conducting material.

The light-transmitting heat-conducting material comprises a main component that is light-transmitting, thereby causing the material as a whole to be light-transmitting. The thermal conductivity of the material is increased in that the mixture also comprises a heat-conducting material. For example, the thermal conductivity of the dispersed phase is> 200 W nf1 KT1, preferably> 500 W nf1 KT1, more preferably> 1000 W nf1 KT1, most preferably> 2000 W rff1 KT1.

For example, the material comprises a composite, ie a mixture of materials, which composite contains a material with a high thermal conductivity, for example a ceramic material and / or a metal and / or metal alloy.

The ceramic material in the composite is, for example, aluminum oxide, alumina, aluminum nitride, silicon carbide, boron nitride, silicon or a silicon-containing composition, graphite, beryllium oxide, quartz or sapphire.

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The metal or metal alloy is, for example, copper, silver, iron, steel, aluminum, bronze, zinc or nickel.

For example, the material is a composite comprising a plastic, further comprising a ceramic material or a metal. Alternatively, the material is a composite of one or more ceramic materials, and / or one or more metals and / or one or more plastics.

In a preferred embodiment, the continuous phase comprises a plastic, preferably a light-transmitting plastic.

Plastics have the advantage that they are generally easy to process, are inexpensive and are widely available.

The plastic is preferably a recycled or reusable plastic.

In a further preferred embodiment the plastic comprises polycarbonate.

Polycarbonate has the advantage that it is a hard material with a high melting temperature. This ensures robust LED lighting. Moreover, polycarbonate has a low expansion coefficient, so that the heat in use hardly causes the LED lighting to expand.

In a preferred embodiment, the dispersed phase comprises carbon particles.

Carbon particles, such as carbon nanotubes (carbon nanotubes, CNT) and graphene, have a very high thermal conductivity.

The properties of CNT are that the conductivity coefficient is around 6600 W iiT1 K_1, which is approximately twice as high as diamond, which was previously the best known heat conductor, the tensile strength is around 63 GPa, the tensile strength of steel is approx. 2 GPa, and the area / weight ratio is in the range of 100-200m2 / g.

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The carbon particles preferably comprise graphene and / or carbon nanotubes.

Alternatively or additionally, the dispersed phase comprises another carbon allotropic, such as graphite.

According to the invention, use is preferably made of a mixture formed from CNT and polycarbonate, called "Borea". By mixing and heating CNT and polycarbonate, a substance is created to provide a plastic with cooling properties. It has been found that this makes the conventional aluminum heat sinks superfluous.

In addition, such a material can be applied to all types of LED chips for dissipating heat.

A further advantage of the illumination in a presently preferred embodiment according to the invention is that a fully light-transmitting admixture becomes possible, whereby a 360 degree radiating behavior is realized.

In the case of an LED lighting in the form of an LED tube, full use is thus made of the reflectors 20 in luminaires for fluorescent tubes.

In an alternative embodiment according to the invention, a closed backside for the lighting is provided so that it is suitable for downward ("downlight") application where a reflection through a reflector is not necessary. Both types of lighting preferably use the Borea technique to dissipate heat.

Conventional LED lighting uses aluminum heat sinks integrated with the housing. These have the disadvantage that they do not transmit light, whereby the beam angle of the LED lighting is drastically reduced. For example, the typical beam angle with a conventional LED tube is 120 degrees. An LED tube according to the invention achieves a greater beam angle, up to even 360 degrees.

Since the housing of the LED lighting forms the heat sink according to the housing and no separate aluminum heat sink needs to be provided, there is more space in the housing for accommodating the at least one LED.

In a preferred embodiment the housing is tubular and the at least one LED is eccentric with respect to the longitudinal axis of the housing.

In the case of an LED tube, the at least one LED is preferably provided on one side of the longitudinal axis of the LED tube. This increases the beam angle to the opposite side. For example, a number of LEDs are provided on a printed circuit board. The circuit board is not placed centrally, but more to one side of the tube, which increases the beam angle in the direction of the LEDs. In other words, the printed circuit board is on one side of the longitudinal axis of the LED tube. Optionally, the material of the housing may comprise a luminescent, phosphorescent or fluorescent substance. This provides an increased light output in the desired wavelength range.

In a preferred embodiment according to the invention, the LED lighting comprises a power supply connected to the at least one LED, which power supply is preferably accommodated in or arranged on the housing.

In conventional LED lighting, a separate power supply must be provided for feeding the LEDs.

For example, the power supply comprises a transformer for converting mains voltage into a voltage suitable for LEDs. Such an external power supply makes installation 7 of a conventional LED lighting cumbersome and complicated.

Compared to conventional LED lighting, the LED lighting according to the invention has the advantage that the power supply is integrated. For example, an LED tube according to the invention can thereby replace a fluorescent tube one-to-one. A simple installation of the LED tube is hereby realized. After all, an LED tube according to the invention can be placed in existing luminaires of fluorescent tubes, since no external power supply component has to be provided. This is in contrast to conventional LED tubes, for which such an external power supply is required.

In a preferred embodiment of the LED lighting according to the invention, the power supply comprises a power supply chip, also referred to as a microchip.

The at least one LED is preferably provided on a printed circuit board (PCB). Here, preferably, the current balance passes through the so-called "microchip" of the lighting according to the invention. This has the advantage that no separate external power supply is required and the LED lighting according to the invention can be used in existing luminaires. In the case of an LED lighting according to the invention in the form of an LED tube, it is therefore preferably interchangeable with conventional lighting tubes, such as fluorescent tubes.

Alternatively, according to the invention, a power supply chip is used in a different type of LED lighting, for example without the light-transmitting and heat-conducting housing material. In other words, the invention also relates to an LED lighting comprising a housing, at least one LED arranged in or on the housing, at least one contact point electrically connected to the at least one LED 8 and a power supply connected to the at least one LED, at preferably a food chip.

Optionally, the LED lighting according to the invention comprises dimming means connected to the LEDs for dimming the at least one LED.

In a further preferred embodiment the LED lighting comprises a safety switch for automatically opening and / or breaking electrical contact with the at least one contact point of the LED lighting when placing or removing an LED lighting in a luminaire. This is particularly advantageous in an embodiment such as an LED tube.

A fluorescent tube generally has a contact point at its both ends for connecting to a fixture. The fixture comprises contact points connected to the mains which, after placing the fluorescent tube in the fixture, connect to the contact points at both ends of the fluorescent tube, so that the fluorescent tube is fed. However, in the case of LED tubes, the two ends 20 are generally electrically connected to each other, so that the risk of an electric shock or damage to the LEDs occurs when the LED tube is placed.

The safety switch in the LED lighting according to the invention reduces or prevents this drawback. By automatically disconnecting the electrical connection from the contact points to the LEDs when the LED lighting is not fully placed in the luminaire, no current can flow through the LEDs. The switch automatically closes the connection between the contact points with the LEDs as soon as the LED lighting has been correctly placed in the luminaire.

The ends of the housing of the LED tube according to the invention can if desired be provided with end pieces, so-called "end caps". The end pieces are preferably glued to the housing.

The safety switch is preferably designed as a microswitch. The microswitch is preferably arranged at the ends of the LED lighting, for example integrated in an end piece ("end cap").

For example, the LED lighting according to the invention is cylindrical or rectangular. Other forms are also possible according to the invention.

For example, the housing is liquid-tight and the housing contains a liquid, such as an oily liquid, for dissipating heat from the LEDs.

The invention further relates to a lighting assembly comprising an LED lighting as described above and a luminaire, a housing, a material and the use thereof, and a method for manufacturing an LED lighting as described above.

The characteristics, advantages and effects described for the LED lighting according to the invention also apply to the lighting assembly, the housing, the material and the use thereof, and the method according to the invention.

The characteristics of the above-described embodiments can be combined as desired in the LED lighting, the lighting assembly, the housing, the material and the use thereof, and the method according to the invention.

The housing according to the invention is preferably a housing for an LED lighting. With regard to the material according to the invention, the continuous phase preferably consists entirely of polycarbonate. Preferably, the dispersed phase consists entirely of carbon nanotubes and / or graphene. Preferably, the dispersed phase comprises carbon nanotubes and / or graphene in a weight percentage or volume percentage between 0% and 20%, more preferably between 0 and 15%, even more preferably between 0 and 10% and most preferably between 1 and 10 %. For example, the 5 volume or weight percentage is 3-10%. The use according to the invention preferably comprises the use of the material according to the invention for manufacturing a housing of a lighting, preferably an LED lighting.

Further advantages, features and details of the invention are elucidated on the basis of preferred embodiments thereof, wherein reference is made to the accompanying drawings, in which: - Figure 1 shows a lighting assembly according to the invention, with an LED tube and a luminaire; Figure 2 shows the LED tube from Figure 1; Figure 3 shows the inside of the LED tube from Figures 1 and 2; Figure 4 shows a schematic representation of an LED lighting according to the prior art; and - Figure 5 shows a schematic representation of an LED lighting according to the invention. Lighting assembly 2 (Figure 1) comprises fixture 4 in which an LED tube 6 is placed. The LED tube 6 (Figure 2) comprises an end piece 8, also called endcap. The end piece 8 is provided with plug pins 10, 12 which serve as an electrical contact point. A microswitch 14 is also provided on end piece 8 which is electrically connected to plug pins 10, 12. On the inside of the tube 6, a printed circuit board 16 is provided, on which LEDs 18, 20 are arranged. The LEDs 18, 20 are electrically connected to plug pins 10, 12 via a microchip 22. This microchip 22 takes care of the current management of LEDs 18, 20.

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The total length of this embodiment is 1172 mm. Three types were used, respectively type A of 396.35 mm for 220 V and 397 mm for 120,100 V, type B of 380 mm for 100, 120 and 220 V, and type C of 395, 65 for 220 5 V and 395 mm for 120 and 100 V. The total height is 2.2 mm with the ICs protruding about 2 mm above the other parts.

The thermal conductivity of this embodiment is about 221 W / mK, the so-called "transmittance" about 90% and the density about 2,680 kg / dm3.

In the embodiments shown, the so-called "endcaps" 8 are provided with a microswitch 14 as protection against an electric shock. The "endcaps" 8 are glued in these embodiments and therefore not screwed.

Figure 4 shows an electrical diagram of an LED lighting 24 according to the prior art, comprising an alternating voltage source 26, an AC / DL converter 30 and one or more LEDs 28. The electrical diagram of an LED lighting 32 according to the invention comprises an alternating voltage source 34 , one or more LEDs 36, an overvoltage protection 38 with a resistor and a voltage regulator, a circuit 40 for reducing electromagnetic interference (EMi) with a condensation and optionally a circuit 42 to prevent blinking. In addition, integrated circuit 14 is provided.

In a comparison between a LED lighting 24 according to the state of the art (Figure 4) and an LED lighting 32 according to the present invention (Figure 5), a number of differences emerge. For example, lighting 32 is provided with a configuration that requires only a limited number of electronic components for the AC control 12 and is furthermore relatively simple in comparison with conventional lighting 24. Furthermore, the space required for the lighting circuit 24 is about 18.5 at 20 mm and for comparable conventional lighting 32, around 5 hundred mm 2. The power factor for lighting 24 is around 0.97 and for conventional lighting 32 around 0.75-0.85. The lifespan under comparable conditions varies for lighting 24 from around 40,000 hours to around 15,000 hours for conventional lighting 2.

The invention is by no means limited to the above described preferred embodiments thereof. The requested rights are determined by the following claims within the scope of which many modifications are conceivable.

Claims (17)

LED lighting, comprising: - a housing; 5. at least one LED mounted in or on the housing; and - at least one contact point electrically connected to the at least one LED, in which the housing is at least partly made of a light-transmitting and heat-conducting material, such that the housing, in use, dissipates the heat produced by the at least one LED, with the characterized in that the light-transmitting and heat-conducting material comprises a mixture, which mixture comprises a continuous phase of a light-transmitting material and a dispersed phase of a heat-conducting material. 2. LED lighting according to claim 1, wherein the thermal conductivity of the light-transmitting and heat-conducting material is greater than 10 W m "1 K" 1, preferably greater than 50 W m -1 K-1, more preferably greater than 100 W nT1 K -1, even more preferably greater than 200 W m "1 K" 1 and most preferably greater than 300 W nf1 K_1. LED lighting according to claim 1 or 2, wherein the transmission of the light-transmitting and heat-conducting material is greater than or equal to 60%, preferably greater than or equal to 75%, more preferably greater than or equal to 90%. LED lighting according to any of claims 1-3, wherein the continuous phase comprises a plastic. 30 LED lighting according to claim 4, wherein the plastic comprises polycarbonate. 6. LED lighting according to any of claims 1-5, wherein the dispersed phase comprises carbon particles. 7. LED lighting according to any of claims 1-6, wherein the housing is tubular and the at least one LED is eccentric with respect to the longitudinal axis of the housing. LED lighting according to any of claims 1-7, comprising a power supply connected to the at least one LED. 9. LED lighting according to claim 8, the power supply comprising a microchip. 10. LED lighting according to claim 8 or 9, the power supply comprising dimming means. 20 11. LED lighting according to any of the claims 1-10, comprising a safety switch for automatically opening and / or breaking electrical contact with the at least one contact point when placing or removing the LED lighting in a luminaire. 12. LED lighting according to any of claims 1-11, wherein the housing is liquid-tight and comprises a liquid, preferably an oily liquid. 30 A lighting assembly comprising a fixture and an LED lighting according to any one of claims 1-12. 14. Housing for a lighting which is at least partly made of a light-transmitting and heat-conducting material, such that the housing dissipates heat in use, characterized in that the light-transmitting and heat-conducting material comprises a mixture, which mixture comprises a continuous phase of a light-transmitting material material and a dispersed phase of a heat-conducting material. A material comprising a mixture comprising a continuous phase of a light-transmitting material and a dispersed phase of a heat-conducting material, wherein the light-transmitting material comprises polycarbonate and the heat-conducting material comprises carbon particles. Use of a material according to claim 15 for use in a housing of a lighting. 17. A method for manufacturing an LED lighting according to any one of claims 1-12, comprising the step of manufacturing at least a part of the housing of the LED lighting from a light-transmitting and heat-conducting material such that it is used by the dissipates at least one led produced heat, characterized in that the method comprises providing the light-transmitting and heat-conducting material as a mixture, which mixture comprises a continuous phase of a light-transmitting material and a dispersed phase of a heat-conducting material.