DE102010004177A1 - LED street lighting - Google Patents

Abstract

The invention relates to a device for illuminating a traffic route, the device comprising a housing (2) for accommodating at least one light source (3), the light source (3) being formed by one or more luminous elements (4) and each luminous element ( 4) has at least one light source (5), preferably a light-emitting light-emitting diode (LED), the light source (5) being arranged on a carrier element (6) and being supplied with electrical energy by means of a ballast. According to the invention, the luminous element (4) is designed as a trough-shaped reflector (7).

Description

The invention relates to a device for illuminating a traffic route according to the preamble of patent claim 1.

State of the art

Devices for illuminating a traffic route are known in a multiplicity of different embodiments. One embodiment is devices for illuminating a traffic route, which use, for example, light-emitting light-emitting diodes (LEDs) as light sources.

The use of light emitting light emitting diodes (LED) is a preferred embodiment for the power consumption of such devices because the power consumption of a light emitting diode (LED) is well below the power consumption of a conventional light source such as a gas discharge lamp.

For example, the document shows DE 20 2007 002 187 U1 a street lamp adaptable with LED technology in a mushroom or suitcase form, whereby a board equipped with LED's is suitable for the connection in different versions, as for example E27, E40, GU10, bayonet or Edisonfassungen.

The stocked with LEDs boards or the rod-shaped LED sockets are used in the horizontal or vertical direction in the lighting device according to conventional lighting.

The disadvantage is that the light rays emanating from the bulbs formed in this way are radiated in all directions, as a result of which a considerable proportion of the light rays fall into regions in which illumination is not required or desired. For example, light rays that radiate to lateral areas may present unwanted glare to drivers of vehicles, residents, and / or nocturnal animals. In addition, due to the radiation characteristic, only a spherical cap-like light distribution is achieved in the illuminated area.

For this reason, the object of the invention is to improve a light distribution of an LED lighting device in a region to be illuminated.

Based on the preamble of claim 1, the object of the invention is achieved by the characterizing features of claim 1.

Advantageous extensions of the inventions are described in the dependent claims.

Disclosure of the invention

The invention is based on a device for illuminating a traffic route, wherein the device comprises a housing for receiving at least one light source, wherein the light source is formed by one or more luminous bodies and each luminous body has at least one light-emitting means, preferably a light-emitting light-emitting diode (LED), wherein the lighting means is arranged on a carrier element and is supplied by means of a ballast with electrical energy.

The essence of the invention is that the luminous body is designed as a channel-shaped reflector.

By a channel-shaped reflector is meant a tubular body which is open to one side in its entire longitudinal direction, whereby lateral boundaries are formed.

The light rays emanating from the light source are shaded by the lateral inner surfaces of the channel-shaped reflector, or, if these are mirrored, reflected.

As a result, shading (vignetting) of the forming light profile is formed according to the linear beam optics. For example, a beam-like light profile can be formed by shadowing in the edge regions. The shape and size of the light profile to be formed is determined by the shape of the reflector, the position of the light source and the distance between the lighting device and the traffic area.

In addition, a uniform illumination of the area to be illuminated can be achieved on a traffic route, since due to the reflection of the light beams in a channel-shaped reflector less loss rays occur.

In a preferred embodiment of the invention it is provided that the channel-shaped reflector has a U-shaped cross section. The U-shaped cross section comprises a lower region and two lateral regions, wherein the edge line of the cross section may be arched, round or edged.

A large portion of the light rays emanating from an LED is reflected at the lateral areas, whereby loss radiation of the light beams can be reduced. In addition, an improved mounting of light sources in the lower region of the channel-shaped reflector is possible.

In a further preferred embodiment of the invention, it is provided that the channel-shaped reflector is dimensioned in the region of a base area for the linear arrangement of a plurality of spaced-apart LEDs. The lower region of an example U-shaped cross-section is formed in the channel-shaped reflector as a flat base of sufficient width. The flat base allows a uniform arrangement and attachment of bulbs. In addition, the distance between the LEDs can be selected such that the light beams overlap in the reflector longitudinal direction at an early stage. As a result, a uniform light profile can be formed.

It is provided in a further preferred embodiment of the invention that the channel-shaped reflector has a base surface which is perforated by at least one recess for the passage of at least one light source.

The light-emitting means (LED) is arranged on a separate carrier element, wherein the carrier element on the outwardly directed surface of the reflector is preferably releasably attachable. This makes it possible, if necessary, a simplified replacement of a possibly defective bulbs or entire carriers possible.

In a further preferred embodiment of the invention it is provided that the luminous element and the carrier element is integrally formed. The base of the channel-shaped reflector forms the support element on which the light source can be arranged directly. This has the advantage that the luminous element in the lighting device has a reduced space requirement. In addition, the one-piece embodiment forms a module character, which facilitates mounting of the luminous element.

It is provided in a further preferred embodiment of the invention that the lighting means is arranged in a focal point of an enveloping parabola of a cross section of the channel-shaped reflector.

The parabola is an axisymmetric curve whose vertex and focus lie on the symmetry axis of the curve. Light rays entering a parabola running parallel to the axis of symmetry are reflected at the parabolic inner surfaces and subsequently pass through the focal point of the parabola. This effect is used in the opposite direction.

The light rays of a luminous means which is arranged in the focal point of a parabolic, channel-shaped reflector are reflected on the lateral inner surfaces of the reflector and emerge in parallel from the reflector.

Only the unreflected direct rays deviate from this direction. Thereby, a light profile with a uniform light distribution can be formed on the surface of a traffic route, which has a high light output due to low loss radiation.

Moreover, it is provided in a further embodiment of the invention that the channel-shaped reflector along a groove longitudinal direction has a focal axis and at least one light source is arranged on the focal axis. The focal axis extends in the axial longitudinal direction through the focal point of the reflector cross-section. The illuminant arranged on the carrier element is positioned on the focal axis of the reflector. The reflected light beams form a uniform light profile in the longitudinal direction of the reflector, while perpendicular to the beam-optical defocusing takes place.

It is provided in a further embodiment of the invention that at least one outer surface of the housing has cooling fins for dissipating heat and / or the housing is formed from a good thermally conductive material, preferably metal. The housing is closed on the surface facing away from the illumination side with a plate-shaped cover, on the surface of which cooling fins for dissipating heat are arranged. The luminous elements are in direct contact via the carrier elements with the cover element of the housing, whereby the heat generated by the luminous means can be dissipated via the carrier elements onto the cooling fins into the environment. By sufficient dissipation of the heat generated by the bulbs, the life of the bulbs can be increased.

Moreover, it is provided in a further embodiment that a plurality of side by side arranged in parallel luminous body are provided in the housing. The parallel arrangement of the luminous body leads to a superposition of individual light profiles in the transverse direction of the channel-shaped reflector, whereby a light profile is formed with a uniform light distribution without diffuse regions within the light profile.

In a preferred embodiment of the invention it is provided that in the housing a plurality of parallel cascades arranged side by side of lighting means are provided, each cascade is arranged on a support member and the light of each cascade is directed by a luminous body according to the invention towards the traffic route. The cascaded arrangement of Illuminant leads to a superposition of light rays in the longitudinal direction of the channel-shaped reflector, whereby a uniform light distribution without diffuse regions takes place.

Further features of the invention will become apparent from the following description of the figures of the embodiment and the drawings.

Showing:

1 a front view of a device for illuminating a traffic route;

2 a rear view of a device for illuminating a traffic route;

3 a perspective sketch of a channel-shaped reflector;

4 a perspective sketch of a support element with light sources arranged thereon;

5 a light beam reflection in a channel-shaped reflector.

In the 1 shown front view of an LED lighting device 1 includes a rectangular housing 2 , wherein the front surface is broken over a large area and closed with a transparent plate material, such as glass or plastic. In the interior of the housing 2 is a light source 3 arranged, consisting of juxtaposed luminous bodies 4 is formed.

The luminous body 4 comprises a channel-shaped reflector 7 , in which several bulbs 5 are arranged linearly one behind the other. The channel-shaped reflector is U-shaped and perpendicular to the longitudinal extent of the housing 2 detachably arranged. The luminous body 4 is suitable for arrangement in different directions and mutual distances. The light source 5 is designed as a light-emitting LED (LED) and is supplied by means of a ballast (not shown) with electrical energy.

On the side surfaces of the housing 2 is a headband 12 swiveling on the housing 2 arranged, whereby an orientation of the housing 2 for optimal illumination of a traffic route is made possible. The headband 12 is by means of a clamp 13 attachable to a lamppost or similar. The LED lighting device 1 is in the illustrated embodiment via an electrical supply line 14 supplied with electrical energy. It is also an energy supply via photovoltaic elements conceivable. These can be, for example, on the back of the case 2 to be ordered.

In 2 is a rear view of an LED lighting device 1 according to 1 shown, with the housing 2 on the surface facing away from the illumination side with a cover 2a is closed. The cover element 2a has on its outwardly facing surface cooling fins 11 on, over which the of the bulbs 5 resulting heat is dissipated to the environment. The cooling fins 11 are integral with the surface of the cover 2a formed, wherein the cover 2a on the back of the case 2 and is detachably arranged by means of a seal. The material of the case 2 and the cover 2a with the cooling ribs arranged thereon 11 is of a metallic material which has good thermal conductivity and corrosion resistance, for example aluminum alloys.

In 3 is a perspective sketch of a channel-shaped reflector 7 as part of a filament 4 shown, which has a U-shaped cross section, wherein the U-shaped cross section is adapted to the course of a parabola. The reflector comprises two legs arranged opposite one another 10 that have a footprint 8th connected to each other. The inner surfaces of the thighs 10 have a mirroring, which forms good reflection properties for incident light rays. The base area 8th is of rectangular and evenly spaced recesses 9 pierced, taking on the outward surface of the base 8th of the reflector 7 the carrier elements 6 with the bulbs arranged thereon 5 can be arranged. The distance and the curvature of the two opposing legs 10 of the reflector 7 is adapted to the light profile to be formed. The height of the thighs 10 the channel-shaped reflector 7 is a multiple of the height of the bulb 5 , In individual cases, ratios of 1: 5 or more are conceivable, the ratio always having to be adapted to the luminous profile properties to be achieved. From the direction of the symmetry axis of the channel cross-section deviating, emerging from the gutter light beams are thereby minimized. The reflector is thus at a maximum number of parallel from the reflector 7 emerging light beams designed to a high light output within a light profile to be formed and a largely sharp boundary on the surface of an In 4 is a perspective sketch of a support element 6 shown what a linear array of bulbs 5 shows. The bulbs 5 are in a consecutive and spaced apart arrangement on the surface of the support element 6 arranged, the bulbs 5 by means of electrical conductors 17 are energized. The carrier element 6 becomes on the outside surface of the base 8th on the channel-shaped reflector 7 arranged such that the bulbs 5 in the footprint 8th arranged recesses 9 succeed. The length of a carrier element 6 is the number of bulbs to be arranged 5 adapted, wherein the carrier element 6 for a series connection of several carrier elements 6 on the channel-shaped reflector 7 suitable is.

In 5 is a light ray reflection of light rays 15 in a channel-shaped reflector 7 schematically illustrated, wherein the light beams 15 from a light source 5 be radiated. The cross section of the channel-shaped reflector 7 is adapted to the shape of a parabola, with the bulbs 5 in the spotlight 16 one the reflector 7 is arranged virtually enveloping parabola. A high proportion of the bulbs 5 outgoing light rays 15 becomes on the surfaces of the thighs 10 reflected and as parallel light rays 15 from the trough-shaped reflector 7 radiated. The parallel light rays 15 form a beam-shaped light profile, wherein the non-parallel, the gutter unreflected directly leaving light rays of the bulb 5 form a weak, optimally no longer perceivable, diffuse brightness range at the edge of the light profile. The diffuse edge region of the intensity of the light profile can be achieved by a juxtaposition of further reflectors 7 be minimized, as the light rays 15 of two adjacent reflectors 7 overlap in the adjacent border areas. One through the focal point 16 the virtually enveloping parabola running in the direction of the groove course forms a focal axis, on which bulbs 5 are arranged linearly one behind the other. In a linear arrangement of several bulbs 5 in a channel-shaped reflector 7 a light profile is generated which illuminates a bar-shaped area almost homogeneously on a traffic route.

LIST OF REFERENCE NUMBERS

1

LED lighting device

2

casing

2a

cover

3

light source

4

illuminant

5

Illuminant (LED)

6

support element

7

reflector

8th

Floor space

9

recess

10

leg

11

cooling fin

12

headband

13

clamp

14

supply

15

beam of light

16

focus

17

conductor path

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 202007002187 U1 [0004]

Claims (10)

Device for illuminating a traffic route, the device comprising a housing ( 2 ) for receiving at least one light source ( 3 ), wherein the light source ( 3 ) by one or more filaments ( 4 ) is formed and each filament ( 4 ) at least one lamp ( 5 ), preferably a light-emitting light-emitting diode (LED), wherein the light-emitting means ( 5 ) on a carrier element ( 6 ) is arranged and supplied by means of a ballast with electrical energy, characterized in that the luminous body ( 4 ) as a trough-shaped reflector ( 7 ) is trained. Apparatus according to claim 1, characterized in that the channel-shaped reflector ( 7 ) has a U-shaped cross-section. Device according to one of the preceding claims, characterized in that the channel-shaped reflector ( 7 ) in the area of a base area ( 8th ) is dimensioned to the linear arrangement of a plurality of spaced apart LED. Device according to one of the preceding claims, characterized in that the channel-shaped reflector ( 7 ) a base area ( 8th ), of at least one recess ( 9 ) for the passage of at least one illuminant ( 5 ) is broken. Device according to one of the preceding claims, characterized in that the luminous body and the carrier element is integrally formed. Device according to one of the preceding claims, characterized in that the lighting means ( 5 ) in a focal point ( 16 ) of an enveloping parabola of a cross section of the channel-shaped reflector ( 7 ) is arranged. Device according to one of the preceding claims, characterized in that the channel-shaped reflector ( 7 ) has a focal axis along a groove longitudinal direction and at least one light source ( 5 ) is arranged on the focal axis. Device according to one of the preceding claims, characterized in that at least one outer surface of the housing ( 2 ) Cooling fins ( 11 ) for the dissipation of heat and / or the housing ( 2 ) is formed from a good thermally conductive material, preferably metal. Device according to one of the preceding claims, characterized in that in the housing ( 2 ) a plurality of luminous bodies arranged side by side ( 4 ) are provided. Device according to one of the preceding claims, characterized in that in the housing ( 2 ) a plurality of parallel cascades of light sources ( 5 ) are provided, each cascade on a support element ( 6 ) is arranged and the light of each cascade by a luminous body ( 4 ) is directed towards the traffic route.

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