EP1362205A1 - Blister lights used for signalling and/or marking purposes - Google Patents

Abstract

Blister lights are used for signaling and/or marking purposes. The blister lights include a housing which is embedded in a traffic area, e.g. a street, an airport runway for taking off and for landing, or the like. It further includes a housing cover by which means the housing embedded in the traffic area can be closed on its upper side, the cover being detachably connected to the housing and including at least one light outlet. It additionally includes an illuminating element which is arranged in the housing and by which the light can radiate through the light outlet of the housing cover. In order to enable the illuminating element to have higher current densities and thus to enable the blister lights to have a higher light output capacity, a thermoconducting bridge is formed between illuminating element and the housing cover. By this, the thermal energy produced by the illuminating element can be conducted to the housing cover From these, the thermal energy is guided to the traffic area via the housing which is embedded therein.

Description

description

Underfloor fire for signaling and / or marking purposes

The invention relates to an underfloor light for signaling and / or marking purposes with a housing which is placed in a traffic area, e.g. a road, airport taxi, take-off and landing runway or the like is embedded, a housing cover, by means of which the housing embedded in the traffic area can be closed on its upper side, which can be detachably connected to the housing, and the at least one Has light outlet opening, and a lamp which is arranged in the housing and can be emitted by means of the light through the light outlet opening of the housing cover.

In known underfloor lights of this type, in which LED (light-emitting diodes) are used as the illuminant, the amount of heat generated during operation of the illuminant is usually converted by convection into a gas, which is often air; In some known underfloor lights, the illuminant is assigned a heat sink, from which the amount of heat generated during operation of the illuminant is released to the gas or air by convection. Because of the limited spatial conditions prevailing in underfloor fires, underfloor fires equipped with a heat sink with a small thermal resistance have a total thermal resistance of typically more than 30 K / W power loss.

With the use of LEDs mounted on PC plates, known from the prior art, there is a thermal resistance between the barrier layer of the LED and the PC plate of more than 150 K / W. In some automated applications, thermal resistance in the order of about 70 K / W is achieved. These high thermal resistance, ω ω MP ¹ cπ o (_π O Cn o cn

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In many cases, the required light emission powers can be achieved with just a single power LED. A maximum of six power LEDs per light outlet opening should expediently be provided as the illuminant.

In order to further optimize the light emission or the light emission power of the underfloor light according to the invention, it is expedient if a collimator element is assigned to the at least one power LED. This collimator element can be used to emit the light radiation directly through the radiation window; alternatively, the light can be emitted by means of the collimator element after a previous reflection on a radiation shape or deflection mirror. The desired distribution of light radiation can be achieved by using collimators, lenses, prisms, diffractors and / or mirrors.

The heat-conducting bridge between the illuminant and the housing cover can be realized in a structurally and technically inexpensive manner if the at least one power LED sits with its carrier plate on a base plate which is attached to and with at least one inner cover part connected to the underside of the housing cover forms the thermal bridge to the housing cover and thus to the housing.

The heat-conducting bridge is advantageously formed by the base plate and two cover inner parts, which are arranged on both sides of the support plate and are connected to the underside of the housing cover.

The two inner parts of the cover can be arranged on the end sections of the base plate, each inner part of the cover advantageously lying flat against the base plate and flat against the underside of the housing cover. > c ιV> IV) h- ¹ P »

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FIGURE 1 is an external perspective view of an underfloor light according to the invention; FIGURE 2 is a first sectional view of the underfloor light according to the invention; FIGURE 3 is a second sectional view of the underfloor light according to the invention; FIGURE 4 is a perspective view of the underside of a housing cover of the underfloor light according to the invention shown in FIGS. 1 to 3; 5 shows a side view of a lamp of the underfloor light according to the invention; FIGURE 6 is a front view of the illuminant shown in FIGURE 5;

FIGURE 7 is a perspective view of the

FIGURES 5 and 6 shown bulbs; FIGURE 8 to

FIGURE 10 Principle representations of further underfloor lights according to the invention; and

FIGURE 11 shows the characteristic curve of a power LED compared to that of a conventional 5 mm LED.

An underfloor light 1 according to the invention shown on the basis of FIGS. 1 to 4 includes a housing 2 which is approximately cylindrical and m a traffic area 3 embedded

The traffic area 3 can be, for example, a street, an airport taxiway, take-off and landing runway or the like. act. The underfloor light 1 is used for signaling and / or marking purposes.

On its upper side, the housing 2 of the underfloor light 1 can be closed by means of a housing cover 4, which can be detachably connected to the housing 2, for example by means of screw connections 5. The housing cover 4 is only slightly, eg less than 13 mm in front of the traffic area. The housing 2 is either directly surrounded by the material forming the traffic area 3, or between the housing 2 and the material forming the actual traffic area 3, thermally conductive building materials, such as epoxy or polyester-filled mortar, are provided.

A line (power) LED 6 is provided as the illuminant within the housing 2. This power LED 6 has a maximum light output power at a through current of approx. 700 to 750 A, as can be seen from FIGURE 11, which shows the light output power as a function of the current intensity for a power LED and for a conventional 5 mm LED ,

The power LED 6 sits on a carrier plate 7, which in turn, as can best be seen in FIG. 5, is connected to a base plate 9 by suitable connecting means 8. The carrier plate 7 of the power LED 6 and the base plate 9 lie flat against one another. The total thermal resistance between the barrier layer of the power LED 6 and the base plate 9 is approximately 11 K / W. For comparison, FIG. 11 shows the corresponding values of a customary 5 mm LED, in which there is a thermal resistance of approximately 220 K / W.

In the exemplary embodiment shown, the power LED 6 is assigned a collimator element 10, by means of which the light output of the power LED 6 can be optimized. The light emitted by the power LED 6 comes out of the collimator element 10 into an optical unit 11, which exits the emitted light through a light exit opening 12 provided in the housing cover 4. The design of the light beam emitted by the underfloor light 1 depends, among other things, on how the optics unit 11 is configured, which lenses, prisms, diffractors, mirrors and the like are adapted according to the desired type of light radiation. can have. In the area of its radiation exit surface, the collimator member 10 is held by means of a lens holder 13, which in turn is connected by means of suitable connecting members 14 to strongly thermally conductive spacers, for example metallic polygonal sleeves 15, protruding from the base plate 9 on both sides of the carrier plate 7.

A shutter 16 is arranged on the side of the lens holder 13 facing away from the collimator member 10. The configuration of the assembly from base plate 9, carrier plate 7, power LED 6, polygonal sleeves 15, collimator member 10, lens holder 13 and shutter or shutter 16 can best be seen in FIGS. 5 to 7.

The base plate 9 is, as can best be seen from FIG. 4, attached to a cover inner part 17, 18 at its two lateral end sections. The two inner cover parts 17, 18 are designed in the same way, so that only the inner cover part 17 is described below.

The inner cover part 17 is, as can best be seen from an overview of FIGS. 2 to 4, connected flat to the underside 19 of the housing cover 4. Accordingly, the inner cover part 17 lies flat against the end section of the base plate 9. The mutually assigned contact surfaces on the inner side of the cover and base plate and the mutually associated contact surfaces on the inner side of the cover and the cover are designed to be metallically smooth in order to ensure undisturbed heat transfer between the base plate 9 and the inner cover part 17 or the inner cover part 17 and the housing cover 4.

In the manner described above, the base plate 9 and the inner cover part 17 or the inner cover part 18 form a heat-conducting bridge between the power LED or its carrier plate 7 and the housing cover 4. The housing cover 4 is in turn connected via a metallically smooth cover-side contact surface 20 to a likewise metallically smooth housing-side contact surface 21, as a result of which the heat is released from the housing cover 4 via the housing 2 to the traffic area or the material forming the traffic area.

Both the carrier plate 7 of the power LED 6 and the base plate 9 and the two inner cover parts 17, 18 are made of a material with a high thermal conductivity coefficient, so that the heat-conducting bridge to the housing cover 4 formed by the base plate 9 and the inner cover parts 17, 18 , the housing cover 4 and the housing 2, a heat dissipation path from the power LED 6 to the traffic area 3 is created. This heat dissipation path has an entire one

Thermal resistance of approximately 1.5 K / W, the traffic area 3 forming a quasi infinitely large heat sink.

In the underfloor fire 1 described above, the heat dissipation from the illuminant or from the power LED 6 is thus effected practically without convection; rather, a heat-conducting bridge to the housing cover 4 is created by means of the inner cover parts 17, 18 and the base plate 9, as a result of which comparatively large amounts of heat are generated via the Housing cover 4 and the housing 2 can be delivered to the traffic area 3. This enables the light output of the power LED 6 and thus the radiation power of the underfloor light 1, which meet all requirements and in which the restrictions regarding the dimensions of the light exit opening 12, which are predetermined by the slight protrusion of the housing cover 4 over the top of the traffic area 3, are easily complied with can.

FIGS. 8 and 10 show a top view of further embodiments of underfloor lights 1 equipped according to the invention with thermal bridges, the embodiment according to FIG. 8 showing a housing cover 4 with two symmetrical to one Axis arranged light outlet openings 12, whereas the embodiment according to FIG 10 has a housing cover 4 with two light outlet openings 12, the symmetry axis enclose an angle.

FIGURE 9 shows a further embodiment of an underfloor light 1 formed with thermal bridges according to the invention with two four power LEDs.

Claims

claims

1. Underfloor fire for signaling and / or marking purposes, with a housing (2), which in a traffic area (3), e.g. a road, airport taxiway, take-off and landing runway or the like, is embedded, a housing cover (4), by means of which the housing (2) embedded in the traffic area can be closed on its top, which can be detached from the housing (2 ) can be connected and which has at least one light outlet opening (12), and a lamp (6) which is arranged in the housing (2) and can be emitted by means of the light through the light outlet opening (12) of the housing cover (4), characterized in that A heat-conducting bridge (9, 17, 18) is formed between the illuminant (6) and the housing cover (4), by means of which thermal energy generated by the illuminant can be conducted to the housing cover (4), from which the thermal energy can be transferred via the housing (2) embedded in the traffic area (3) can be derived toward the traffic area (3).

2. Underfloor light according to claim 1, in which at least one power LED (6) is provided as the illuminant.

3. Underfloor fire according to claim 1 or 2, in which a maximum of six power LEDs (6) are provided per light exit opening (12) as the illuminant.

4. Underfloor fire according to claim 2 or 3, wherein the at least one power LED (6) is assigned a collimator element (10).

5. Underfloor fire according to one of claims 2 to 4, wherein the at least one power LED (6) with its carrier plate (7) sits on a base plate (9) which is connected to at least one with the underside of the housing cover (4)

Inner cover part (17, 18) is attached and forms the thermal bridge (9, 17, 18) to the housing cover (4) with this.

6. Underfloor fire according to claim 5, wherein the base plate (9) by means of two cover inner parts (17, 18), which are arranged on both sides of the carrier plate (7), is connected to the underside of the housing cover (4).

7. Underfloor fire according to claim 6, wherein the two inner cover parts (17, 18) are arranged at the end portions of the base plate (9).

8. Underfloor fire according to one of claims 5 to 7, in which each inner cover part (17, 18) on the one hand flat against the base plate (9) and on the other hand flat against the underside of the housing cover (4).

9. Underfloor fire according to one of claims 5 to 8, in which the mutually assigned contact surfaces on the inside of the cover part and base plate side as well as the mutually associated contact surfaces on the inside and cover side and cover sides are of metal-smooth design.

10. Underfloor fire according to one of claims 1 to 9, in which the mutually assigned cover-side (20) and housing-side contact surfaces (21) are of smooth metallic design.

11. Underfloor fire according to one of claims 5 to 10, wherein the base plate (9) made of a material with a high coefficient of thermal conductivity, e.g. is made of a metal.

12. Underfloor fire according to one of claims 5 to 11, wherein the carrier plate (7) of the power LED (6) made of a material with a high coefficient of thermal conductivity, e.g. is made of a metal.

13. Underfloor fire according to one of claims 5 to 12, wherein the one or more lid parts (17, 18) made of one material it is designed with a high coefficient of thermal conductivity.