HUP0900583A2 - Lamp modul with led and luminaire for street lighting - Google Patents

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LED-based public lighting lamp module and modular public lighting luminaire arrangement

The invention relates to an LED-based public lighting lamp module and to a modular public lighting luminaire arrangement assembled from public lighting lamp modules.

In order to achieve the brightness and/or illumination values set out in the public lighting standards (MSZ EN 13201), public lighting luminaires must create a predefined light distribution, for example the “bat wing” light distribution shown in Figure 1. In the figure, the luminous flux of the light source is standardized to 1000 Im. The characteristic of energy-efficient light distribution is that the luminaire used radiates at a smaller angle perpendicular to the road than in the direction of the longitudinal axis of the road. Thus, the luminous flux of the luminaire falls predominantly on the road surface to be illuminated, and not too much light is emitted next to the road. The light entering the environment is both a waste and an unnecessary burden on the illuminated natural objects, and may disturb residents in the area. According to experience, the light distribution of a public lighting luminaire is good if the highest light intensity in the longitudinal direction of the road is in the range above 60° from the vertical, sometimes in the direction of 72° - 73°. At the same time, in order to avoid glare, the light emitted above 80° must be limited, and the luminaire must not emit light at all above 90° due to light pollution. This is achieved in modern luminaires by closing with flat glass, because in these luminaires even the light flux scattered from the bulb is not directed towards the sky. Classic public lighting luminaires that implement the “bat wing” light distribution usually contain a high-luminosity light source - sometimes with a luminous flux of up to several thousand lumens - and an optical system that is usually specially shaped, such as a “freeform” mirror or lens. The light sources are manufactured in different power levels. Thus, in public lighting

-2most common sodium lamps, mercury lamps, metal halide lamps, compact fluorescent lamps, etc. are available in the power range of 18 - 400 W.

The design of modern luminaires is such that the relative position of the light source with different power and the “freeform” optics can be changed or shifted along one or two axes in fixed positions, thereby characteristically changing the light distribution emitted by the luminaire. In practice, with a well-designed optic, a modern luminaire can emit up to 5-10 different light distributions depending on the relative positioning of the light source and optics. By modifying the light distribution, the light flux emerging from the lamp can be directed largely to the road surface to be illuminated, usually rectangular. This is similar to the focusing of imaging optical systems, when the image of the object is focused and sharpened on the screen by moving the imaging lens. A simple modification of the light distribution allows the luminaire to meet the uniformity requirements prescribed in public lighting standards for different column heights, column spacing and road widths, while meeting the glare requirements. The luminaire families designed in this way can economically and energy-efficiently implement the low brightness (0.3 cd/ ^m2 ) or illumination (5 lux) levels required for low-traffic side streets, up to the high brightness (2 cd/ ^m2 ) or illumination (50 lux) levels required for urban access sections of motorways, and they also meet the uniformity requirements for various traffic situations.

The luminous flux of currently available LEDs (Light Emitting Diodes) is significantly lower than that of high-performance lamps. Therefore, it is necessary to install many high-performance LEDs, 5-10 pcs, and in the case of higher brightnesses up to 50 pcs, in a luminaire in order to achieve the luminous efficiency of modern, high-performance public lighting lamps. Due to cooling problems, the LEDs must be placed at a sufficient distance from each other, because the heat generated in the LEDs can practically only be dissipated by heat conduction. To do this, sufficiently thick and good thermal conductivity fixing elements and cooling blocks must be designed. In the case of classic lamps, the heat loss is good

-3% of it is emitted as infrared radiation through the window or lampshade. LEDs practically do not emit in the infrared range, therefore the waste heat, which is approximately the same as the waste heat produced in more common modern lamps, must be conducted from the LED chip to the surface of the luminaire, from where it is dissipated into the environment by heat transfer, conduction, or radiation.

Due to the arrangement of the LEDs and the need to design heat dissipation, the usual public lighting mirrors and optical arrangements cannot be used in LED luminaires. The size of current light sources is large compared to LEDs, and they radiate continuously in space. The public lighting mirrors currently used transform the light distribution of an extensive continuous light source into the characteristic “bat wing” distribution used in public lighting. LED luminaires have several small light sources, offset from each other for cooling. The task of the optical system of LED luminaires is to combine and shape the individual light distributions of small, discrete light sources in offset positions with good efficiency so that they together provide the necessary light output and the optimal “bat wing” distribution for solving the public lighting task.

A common solution is to use a special “freeform” lens matched to the individual LEDs, which shapes the light flux of each individual LED into a “bat-wing” distribution. These maintain the desired distribution when combined. Since the light output of the LEDs is still small, in order to achieve the appropriate brightness or illumination, matrices are formed from the LEDs and special lenses, which consist of up to 10-20 LED+lens elements. The luminaire is built from these matrices, which also provide a surface for mounting and cooling. The luminaire formed in this way forms a closed, compact unit, the cooling is efficient, and the “freeform” lenses can be produced cheaply in large series. The lenses close the LEDs, no additional protection or hood is required.

-4llyen solution is described as an example in the product brochure available at http://www.osramos.com/osram os/EN/News Center/Spotliqhts/Success Stories/ download/Fly er Starium Dragon 60.pdf.

US 6,250,774 B1 describes a luminaire comprising a plurality of LEDs aligned in different directions and optics mounted thereon. The light distribution suitable for solving the public lighting task is varied by the direction of the LEDs and the collimation angle of the optics.

However, the disadvantage of the LED luminaire designed with “freeform” lenses and the luminaires described in certain embodiments of the US 6 250 774 B1 patent specification is that their light distribution cannot be modified. The luminaire designed in this way is optimized for a given lighting task. Since the light distribution is frozen in the case of LED lamps with “freeform” lenses, in the case of arrangements that differ from the geometry assumed during optimization (column spacing, column height, road width), the lamp cannot provide a good efficient solution for the given lighting situation. Another problem is that according to design experience, the maximum radiation of “freeform” lenses is only around 60°, not reaching the ideal angle of 72° - 73°. The efficiency of the lens collimators used for LEDs is only about 85%. Some of the losses are of geometric origin, but the main reason is that it is not possible to apply a good anti-reflection coating to complex, highly curved surfaces, and the application of an anti-reflection coating is only possible at very high cost. Thus, light suffers losses both when entering and exiting the lens due to Fresnel reflection.

According to the patent specification US 6 250 774 B1, the LEDs are glued to the heat sink with a hemispherical adapter. This allows the LEDs to be tilted along two axes during production, but the heat dissipation is worse than in the case of a fixed, relatively large cross-section mounting. In the various embodiments described, the light must pass through several beam-shaping elements to achieve optimal light distribution, which significantly increases the loss and scattered light compared to a simple mirror system.

-5When creating the invention, we set the goal of creating an LED-based public lighting lamp module, or using it, a modular public lighting luminaire arrangement, which is free from the disadvantages of the prior art solutions. Our goal was to create a public lighting lamp module and arrangement that can be easily and inexpensively designed, easily adjusted to the given application conditions, effectively achieving the required light distribution, and enabling effective cooling. Our goal was also to create a solution that can be easily controlled and diagnosed.

The objects of the invention are achieved by a public lighting lamp module according to claim 1 and a modular public lighting luminaire arrangement according to claim 12. Preferred embodiments of the invention are defined in the subclaims.

In the following, preferred embodiments of the invention are described by way of example with reference to the drawings, where the

Figure 1 shows an example of a predefined light distribution, the so-called bat wing distribution diagram,

Figure 2 is a schematic vertical section of a public lighting lamp module according to the invention mounted on a road lighting system, the

Figure 3 is a cross-section of the optical arrangement of a simplified public lighting lamp module with a flat deflecting mirror,

Figure 4 is a three-dimensional bottom view of a preferred public lighting lamp module according to the invention,

Figure 5 is another bottom view of the public lighting lamp module according to Figure 4,

Figure 6 is a top view of the public lighting lamp module according to Figure 4,

Figure 7 is a cross-section of a public lighting lamp module according to the invention, provided with a cover,

Figures 8 and 9 show details of a public lighting lamp module according to the invention, providing variable light distribution, in two spatial views, and

Figures 10-12 are schematic diagrams of preferred street lighting luminaire arrangements equipped with a street lighting lamp module according to the invention.

-6According to the invention, we have recognized that for a given application, individual mirror collimators mounted on LEDs are more efficient than prior art lens collimators. The efficiency of available mirror collimators is 92% or more, since most of the “light going in the right direction” exits the mirror collimator freely, without reflection, i.e. without loss. In this case, the shaping and directing of the light beam can be achieved by installing a collimator with the appropriate angle and by adjusting the axis of the optical element formed by the LED+mirror at the appropriate angle.

We have also recognized that to create a predetermined light distribution, for example a bat wing light distribution, multiple mirrorless LEDs or, in some cases, LED+mirror at different angles are required. Mirrorless LEDs are preferably rotated around an axis parallel to the longitudinal axis of the road, at a large angle, but mostly in a plane perpendicular to the road. The preferably used LEDs equipped with a mirror collimator radiate at a much smaller angle, more in the longitudinal direction of the road, roughly directed towards the two corners of the road farthest from the post. The LEDs directed towards the far corners are rotated around two axes. The exact direction of the LEDs can be determined by computer optimization. When designing the optical system, the LEDs must be positioned so that the LEDs or LED+collimator elements rotated in different directions do not cover each other's light as much as possible. Therefore, the position of the LEDs must be optimized: the LEDs must be offset relative to each other in three directions of space. During optimization, the optical effect of the heat sinks used to fix the LEDs, which are placed and rotated in the correct position, must also be taken into account (shading, reflection, light absorption, etc.). At the same time, in order to ensure effective heat dissipation, sufficiently thick heat sinks and cooling elements must be used. In the optical system, the LEDs are preferably located symmetrically on a plane perpendicular to the road.

The LED-based public lighting lamp module 10 according to the invention, therefore, comprises 14 LEDs as light sources, as well as mirrors for directing their light. As shown in particular in Figures 2 and 3, the public lighting lamp module 10 according to the invention comprises an interior space 12, 14 LEDs positioned and oriented in accordance with a predetermined light distribution in the interior space 12, of which at least one 14 LED is preferably also provided with collimator optics 24, and flat deflecting mirrors 16a, 16b, 16c, 16d forming the light-deflecting inner surface of the interior space 12. As described above, one or more 14 LEDs equipped with the 24 collimator optics are preferably arranged at a smaller angle, radiating in the longitudinal direction of the road, approximately directed towards the two corners of the road farthest from the post. LEDs 14 without a collimator preferably radiate at a larger angle, essentially perpendicular to the road surface.

The LEDs 14, which are placed in a suitable position in space and rotated in given spatial directions, and are preferably equipped with partially aspherical mirror optics, are surrounded on four or five sides by a mirror system consisting of flat deflecting mirrors 16a-16d, as shown in Figures 2-5. One side of the optical system consisting of flat deflecting mirrors 16a-16d defines an optically open, rectangular light exit opening 11, where the appropriately shaped light beam leaves the public lighting lamp module 10.

The public lighting lamp module 10 according to the invention preferably comprises two pairs of deflecting mirrors 16a, 16b; 16c, 16d, in which pairs the deflecting mirrors 16a, 16b; 16c, 16d are arranged opposite each other, and which deflecting mirror pairs are arranged so as to define the inner space 12 expanding towards the light exit opening 11. According to the invention, it is of course also possible to use a number of deflecting mirrors other than four; in the illustrated embodiments, for example, a fifth plane for mounting the LEDs 14 can also be formed with a deflecting mirror function.

The role of the flat deflecting mirrors 16a-16d is complex: on the one hand, the mirrors deflect the light of the LEDs 14 mounted without collimator optics 24 towards the road surface to be illuminated (20 sidewalks, 22 roadway), and on the other hand, they prevent the wide-angle beams from leaving the luminaire mounted on the support pole 18 and containing the public lighting lamp module 10. This on the one hand increases the efficiency of the public lighting lamp module 10 and reduces the light reaching the road environment. On the other hand, they prevent the so-called light pollution, i.e. the public lighting lamp module 10 does not radiate light towards the sky.

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According to one preferred embodiment, as shown in Figure 2, the section of the street lighting lamp module 10 taken in a plane perpendicular to the longitudinal axis of the road resembles a sloping roof. Since the support column 18 is on one side of the road, a front deflector 16a is flatter than the horizontal, and a rear deflector 16b is inclined at a steeper angle so that the light beam of the street lighting lamp module 10 sufficiently illuminates the area of the road opposite the support column 18 and, if necessary, the sidewalk opposite the support column 18. The inclination angle of the front and rear deflectors 16a, 16b can be suitably changed so that good efficiency and uniformity of illumination or brightness can be achieved even in the case of different column heights or varying road widths.

Figure 3 shows a cross-section of a simplified LED street light module 10 with a flat reflector optical arrangement in a plane perpendicular to the road plane. The figure clearly shows the direct and reflected wide-angle light beams emerging from the street light module 10. The street light module 10 preferably also includes one or more heat sinks 26 carrying one or more LEDs 14 for removing heat from the interior 12. The heat sinks 26 are preferably heat sinks arranged in a manner that minimizes shading.

In Figures 4 and 5, an example of a bat wing light distribution! LED street lighting lamp module 10 is shown in two spatial bottom views. The street lighting lamp module 10 is designed with a hexagonal, open on one side, chiral mirror optical system. The street lighting lamp module 10 has 2x3 symmetrically arranged LEDs 14, shifted and rotated in the appropriate direction. For the sake of simplicity, the collimator optics 24 have not been shown in the figure. The LEDs 14 are fixed to suitably thick, good thermal conductivity cooling elements 26, cooling blocks. The cooling elements 26 are thermally connected to a cooling fin 27, shown in more detail in Figure 6, placed on the top of the street lighting lamp module 10, and are preferably fixed thereto. The heat loss of the LEDs 14 is transferred to the environment by the cooling fin 27.

In the preferred embodiment shown in Figures 4-6, the public lighting lamp module 10 comprises deflecting mirrors 16a, 16b, 16c, 16d defining a rectangular light exit opening 11, where in one of the deflecting mirror pairs the deflecting mirrors 16c, 16d are arranged parallel to each other, and in the other the deflecting mirrors 16a, 16b are arranged diverging towards the light exit opening 11. This enables a simple construction and, by mounting them side by side, a modular public lighting arrangement.

Figure 7 shows another street lighting lamp module 10 housed in a housing 28 in a cross-section taken in a plane perpendicular to the road plane and parallel to the longitudinal axis of the road. Some of the LEDs 14 are equipped with aspherical mirror collimator optics 24.

As shown in Figures 8 and 9, the front and rear deflectors 16a, 16b can advantageously be rotated about axes arranged along their upper sides, so that the ratio of the length and width of the illuminated area can be modified by adjusting the angle of the two rotatable deflectors 16a, 16b: in the case of a lower support post 18 or a wider roadway, the angle enclosed by the two deflectors 16a, 16b is larger, in the case of a higher support post 18 or a narrower roadway, the angle enclosed by the two deflectors 16a, 16b is smaller. The deflectors 16a, 16b, which are arranged divergingly towards the light exit opening 11, are therefore fixed in the public lighting lamp module 10 with a hinged connection 30 allowing the adjustment of the angle enclosed by each other. In Figures 8 and 9, for the sake of simplicity, the side deflectors 16c, 16d are not shown. The figures show that the LEDs 14 are mounted via printed circuits 32.

As mentioned above, the public lighting lamp module 10 is preferably symmetrically designed with respect to a vertical center plane and includes LEDs 14 arranged vertically and/or horizontally offset relative to each other in the interior space 12 in a shading-minimizing arrangement. The LEDs 14 offset relative to each other are preferably also rotated relative to each other along a vertical and/or horizontal axis to ensure a predetermined light distribution.

-10The open, planar light exit opening or surface 11, where the light leaves the optical module, is preferably closed by a cover plate 29 made of transparent material, e.g. a flat tempered glass plate or a shatterproof plastic plate, thereby achieving a light pollution-free closure and the IP67 protection against water and dust, which is a requirement for modern luminaires. According to the known Fresnel reflection laws, wide-angle beams pass through the flat glass plate only with a high reflection loss. By properly collimation and directing the aspherical mirrors mounted on the 14 LEDs, the loss caused by the Fresnel reflection occurring on the closing flat glass plates can be compensated. By using aspherical mirrors, high-intensity wide-angle beams can be created even in the case of a flat glass closure. At the same time, the light rays reflected on the flat glass plate are partially directed by the plane mirror optical system onto the road surface to be illuminated, thereby improving the efficiency of the 10 public lighting lamp modules. The task of optical design is to determine the shape of the aspherical mirrors and the angle of the plane mirrors so that the bat wing light distribution is created as efficiently as possible with the lowest loss.

Figures 10-12 show schematic diagrams of preferred street lighting luminaire arrangements with modules placed side by side according to the invention. Figure 10 shows a top view of an arrangement arranged in a line parallel to a road. Here, the “hoods” are in a line, the street lighting lamp modules 10 are in contact with each other with flat plates. This leads to a more compact arrangement, but slightly reduces the cooling efficiency. Figure 11 shows a side view of an arrangement arranged in a line perpendicular to a road. The “hoods” are arranged one behind the other, the modules meet along a line. Figure 12 shows a block arrangement in top view, where preferably the horizontal direction in the figure corresponds to the direction parallel to the road. In the illustrated arrangements, the light exit openings 11 of the street lighting lamp modules 10 preferably fall in a plane, which plane is parallel to the road surface to be illuminated.

-11 The invention therefore relates to an LED optical module and a luminaire family or arrangement formed from one or more public lighting lamp modules, in which the arrangement and directionality of the 14 LEDs, the 24 collimator optics mounted on each 14 LEDs and the optical system consisting of the flat deflecting mirrors 16a-16d replace the light source of the public lighting bodies and the optical arrangement implementing the bat wing light distribution. The described LED optical module and luminaire family are also competitive with modern public lighting lamps in terms of light output and light distribution body variability. The performance of the optical module can be changed by installing fewer or more high-power LEDs in the given LED positions and locations in a given geometric arrangement, or by not installing LEDs in certain LED positions. In addition, the performance of the LEDs can also be selected for the given application.

The "bat wing" light distribution is achieved by the appropriate spatial placement, rotation and mirrors of the LEDs. Only a finite number of LEDs can be optimally placed in a module. The number of LEDs within the module is influenced by two factors: on the one hand, due to effective heat dissipation and shielding, the LEDs cannot be too close to each other, and on the other hand, the LEDs cannot be too far from the mirrors, because then either the size of the mirror must be increased proportionally, or in the case of small mirrors, the LED light will pass by the mirror. Due to these two aspects, a finite number of LEDs can be designed in a module. According to our design experience, the number of LEDs optimally varies between four and ten. Some of the four to ten LEDs, approximately two to four pieces, are equipped with the aspherical mirror 24 collimator optics, which provides approx. It collects its light, which is scattered at an angle of 80° - 90°, into an angle of 20° - 30°. The collimated light contributes greatly to the formation of the “bat wing” distribution. The axes of the collimated optics point in the direction of the highest light intensity, greatly increasing the light emitted in the critical direction. The other LEDs radiate freely within the module, without collimating optics.

Since, as mentioned, the number of LEDs in an optical module is limited, to achieve higher brightness or illumination values, a public lighting system

-12-layout requires multiple modules to be installed in one luminaire, luminaire arrangement, for example as shown in Figures 10-12

The invention is of course not limited to the preferred embodiments described in detail above, but further changes, modifications and improvements are also possible within the scope of protection defined by the claims. The public lighting lamp module may also include additional elements, mirrors, and the predetermined light distribution may not only be a bat wing distribution, but also any necessary, prescribed light distribution.

Claims (13)

-13- : -. : ··· · · · ·· Patent claims 1. LED-based public lighting lamp module (10), which comprises LEDs (14) as light sources and mirrors for directing their light, characterised in that it comprises - interior (12), - LEDs (14) positioned and oriented according to a predetermined light distribution in the interior (12), and - flat deflecting mirrors (16a, 16b, 16c, 16d) forming the light-diffusing inner surface of the interior space (12). 2. A public lighting lamp module according to claim 1, characterized in that it comprises two pairs of deflecting mirrors (16a, 16b; 16c, 16d), in which pairs the deflecting mirrors (16a, 16b; 16c, 16d) are arranged opposite each other, and which deflecting mirror pairs are arranged defining an inner space (12) expanding towards a light exit opening (11). 3. A public lighting lamp module according to claim 2, characterized in that it comprises deflecting mirrors (16a, 16b, 16c, 16d) defining a rectangular light exit opening (11), where in one of the deflecting mirror pairs the deflecting mirrors (16c, 16d) are arranged parallel to each other, and in the other the deflecting mirrors (16a, 16b) are arranged diverging towards the light exit opening (11). 4. A public lighting lamp module according to claim 1, characterized in that it comprises at least one deflecting mirror (16a, 16b) which is fixed by a hinged connection (30) enabling adjustment of the angle of the deflecting mirror (16a, 16b). 5. A public lighting lamp module according to any one of claims 1-4, characterized in that it is symmetrically designed with respect to a vertical center plane and comprises LEDs (14) arranged in an arrangement that minimizes shading, vertically and/or horizontally offset from each other in the interior space (12). -14- : ··: : ··· · · · ·· 6. Public lighting lamp module according to claim 5, characterized in that the LEDs (14) offset from each other are rotated relative to each other along a vertical and/or horizontal axis to ensure a predetermined light distribution. 7. A public lighting lamp module according to claim 1, characterized in that it comprises one or more heat sinks (26) carrying one or more LEDs (14) for dissipating heat from the interior space (12), said heat sinks (26) preferably being heat sinks arranged in a shading-minimizing arrangement. 8. Public lighting lamp module according to claim 1, characterized in that at least one LED (14) of the LEDs (14) is provided with collimator optics (24), which collimator optics (24) is preferably an aspheric mirror optic. 9. The public lighting lamp module according to claim 1, characterized in that the predetermined light distribution is a bat wing distribution. 10. A public lighting lamp module according to claim 1, characterized in that between four and ten LED locations are provided for the LEDs (14), and LEDs (14) of a number and power appropriate for the given application are mounted in the module (10) on these LED locations. 11. Public lighting lamp module according to any one of claims 2-4, characterized in that the light exit opening (11) is covered with a cover plate (29) made of transparent material. 12. Modular public lighting luminaire arrangement, characterized in that it comprises public lighting lamp modules (10) according to any one of claims 1-11, placed next to each other. 13. Arrangement according to claim 12, characterized in that the light exit openings (11) of the public lighting lamp modules (10) fall in a plane, which plane is parallel to a road surface to be illuminated. (6 sheets of drawings, 12 figures)