WO2011054853A1

WO2011054853A1 - Led lamp and lighting unit using same

Info

Publication number: WO2011054853A1
Application number: PCT/EP2010/066717
Authority: WO
Inventors: Klaus Schmidt
Original assignee: Lightdesign Solutions Gmbh
Priority date: 2009-11-04
Filing date: 2010-11-03
Publication date: 2011-05-12
Also published as: DE202010004789U1; WO2011054508A1; JP2011100714A; DE202009015012U1

Abstract

The invention relates to an LED lamp for use in a lighting unit. The LED lamp comprises an LED as a light source (11) and a heat sink (14) made of heat-conducting material for dissipating heat from the light source (11). The heat sink (14) comprises a carrier surface (12, 13) on which said light source (11) is fastened in a heat transferring manner, wherein the carrier surface (12, 13) is part of a carrier element (16) of the heat sink (14). The heat sink (14) further comprises a base (19) for mounting the LED lamp in a lighting unit, wherein the carrier surface (12, 13) and surface of the base (19) adjacent thereto are at an angle to each other, and the transition between the two surfaces is continuous throughout. Such an LED lamp is disposed in a lighting unit such that the light source (11) thereof is located at least approximately in the optical center of a parabolic mirror-like reflector (25) and that the main beam path of the light from the light source (11) reflected by the reflector (25) runs substantially parallel to the optical axis (26) of the reflector (25).

Description

LED lamp and lighting unit using the same

The invention generally relates to a lighting unit with LED lamp for a stationary luminaire for illuminating a larger area, such as e.g. in the street space.

In particular it relates to such lighting units whose LED lamp comprises at least one light source which is disposed at least approximately at the optical center of a molded in the manner of a parabolic reflector of the lighting ^¬ unit, so that the main beam direction of the light reflected from the reflector light of the light source in the

Substantially parallel to the optical axis of the reflector.

The invention equally relates to an LED lamp of such a lighting unit, which has at least one LED as the light source. The heat generated by the light source is dissipated by a heat sink having a support surface for heat-transferring attachment of the light source.

In times past energy-saving fluorescent ^¬ strong LED lamps in various areas are increasingly applied. In US 2003/0185005 Al, for example, a diode-based signal light source is described, in which the light ^¬ source, a plurality of grid-like manner on a diode carrier

arranged LEDs arranged approximately in the optical center of a parabolspiegelförmigen reflector is arranged such that the main beam direction of the reflector

reflected light is substantially parallel to the optical axis of the reflector. The light passes through a lens disc, so that it hits the surface to be illuminated glare-free. Furthermore, high-performance LEDs, which ensure a very high light output with minimal space requirements and a high efficiency of about 90%, are used for street lighting. However, the technical problem of dissipating the heat associated with the generation of light must be solved. This problem is especially true then

relevant if a plurality of high-power LEDs in a compact design in a small space or small area are to be arranged as a so-called light module to generate the required light intensity or amount of light.

For heat dissipation, e.g. in DE 10 2007 040 444 AI described an LED lamp with a cooling base. This cooling base has a ventilation system which is formed by a plurality of ventilation ducts extending in the interior of the base. Through the ventilation ducts air can flow through and provide the necessary heat transfer. In DE 20 2008 007 267 Ul an LED lighting system is described, in which the LED is mounted as a light source on a pedestal, which acts as a heat dissipator and the back has a structured and thus enlarged surface for heat dissipation to the environment. In this lighting system is the

preferred main beam direction generated by a lens system, which is arranged directly in front of the LED. A disadvantage of both embodiments, on the one hand, the insufficient heat dissipation for the use of high-power LEDs and on the other hand, the complex and therefore costly

Layout .

The invention has for its object to provide a lighting ^¬ unit of the type mentioned in a sufficiently powerful design simple and inexpensive to produce while avoiding harmful overheating of the LED light source for glare-free lighting of roads and other public transport areas z. B. used in lamp housings of mast lights can.

This object is achieved according to the invention by a usable in a lighting unit LED lamp having a support surface as part of a support member of a heat sink and a foot of the heat sink for mounting the LED lamp in the lighting unit, wherein the support surface of the support member and an adjacent thereto surface of the foot ^¬ part are at an angle to each other and the transition between two surfaces runs steadily everywhere. This LED lamp is so in a parabolic reflector of a

To arrange lighting unit that the light source of the LED lamp at least approximately in the optical center of the

Reflector is located and the main beam direction of the

Reflector reflected light from the light source

Substantially parallel to the optical axis of the reflector. To the preferred location of the light source in the

To realize the optical center of the reflector, carrier element and foot part are always to each other so that the support surface and an adjacent surface of the foot are at an angle to each other.

In a lighting unit in which the LED lamp is arranged with its foot part comparable to a socket in the base of the parabolic mirror-shaped reflector, the angle between the two said surfaces is preferably in the range between 90 ° and 135 °. This is perpendicular to the

Reflector standing or pyramidal support elements with two or more support surfaces possible. In particular, by extending at an acute angle to the optical axis support surfaces additional Lichtleiteffekte can be achieved, which may be advantageous for certain requirements. An adaptation of the reflection direction of the light of a light source arranged on such carrier surfaces, so that the described main beam direction of the illumination unit can be realized, can be determined by the position of the carrier surfaces and or the reflector form done.

The subdivision of the heat sink in the support member and foot realized for the first the heat transfer from the light source to the support member via the attachment of the light source on the support surface and further heat ^¬ dissipation in the foot due to the good heat conducting properties of the material of the heat sink. About the foot ^¬ part, with which the LED lamp is mounted in a lighting unit, then the heat dissipation to an actively coolable or external component of the lighting ^¬ unit can be done. As a good heat-conducting material, for example, a metal such as aluminum or copper may be used. Other, eg ceramic materials are usable. According to a further embodiment of the invention, the heat sink at its foot on a flat level ^¬ surface, with which the heat sink heat transfer to a frame part of a lamp housing of a lamp

can be mounted. In this way, good heat dissipation to other parts of the lamp housing is possible over the footprint. These can be actively cooled or lie outside and are cooled atmospherically. In the case of the known design of a reflector with a central arrangement of the LED lamp, the footprint is perpendicular to the plane of symmetry of the heat sink. Depending on the position of the support surfaces and the shape of the reflector, however, other orientations of the base are possible. The

described design of the heat sink offers in addition to the manufacturing and assembly technical advantage that the heat sink consists of one piece, also the functional advantage to ensure good cooling properties.

In addition to the material in particular, the transition from the carrier element to the foot has a significant influence the heat dissipation. It has surprisingly been found that the heat dissipation is significantly better when the transition between the support surface and an adjoining surface of the foot continuously runs continuously. Steady is to be understood that in the transition between the two surfaces no kink or crack is formed. Such a continuous transition is realized for example by a throat, which is formed from one or more merging radii. According to a preferred embodiment of the invention, a good heat dissipation is also realized by a one-piece design of the heat sink. In this way, disturbances in the heat dissipation are to be avoided by interfaces and a continuous heat conduction from the support surface to the base of the foot part of the heat sink possible.

A further improvement of the heat dissipation by the one-piece heat sink is achieved in that this from a continuous casting profile by machining such. Milling is made. Thus, a heat sink is provided, the inner, produced by casting structure and associated thermal conductivity by dislocations due to compression or train was not or only minimally reduced. With such an LED lamp and lighting unit, which can be produced not only very simple and inexpensive, can be achieved with a relatively low energy consumption of about 30 W to 40 W very high light output with a LED Lichtström of for example 2400 Im (lumens) , The design principle used here can be varied in a very simple manner and adapted to the particular requirements.

Thus, for example, arranged with several grid-like LEDs, which are arranged on one or more diode carriers and fixed by means of the diode carrier over the entire surface on the support surface, a larger traffic area from about 5 m height can be sufficiently illuminated, there is also the possibility of an embodiment of the invention

Claim 3, wherein more than two diode carriers can be provided to obtain a greater light intensity.

In combination with the paraboloidal reflector commonly used, the one described above

Arrangement and design of the support element to a uniform light distribution on the illuminated

To get traffic area. Thus, in addition to the arrangement of a plurality of carrier surfaces on the carrier element, it is also possible to arrange a plurality of LEDs or light modules on a carrier surface in order to obtain a higher intensity of light.

It is also advantageous if the reflector is releasably secured to the heat sink and with this a structural

Assembly unit forms. This allows easy access to the LED lamp for maintenance purposes, in particular to their

Exchange. In addition, the structural mounting unit formed of LED lamp and reflector can be easily

produce and easy to handle montageetechnisch.

With appropriate design of the heat sink, e.g. of the foot part to which the reflector can be fixed, it is also possible, instead of the normally round reflector, also to provide an oblong reflector for the illumination of corresponding surface forms, this being e.g. can be made in two parts for easier installation. In this case, the two reflector halves can be joined together at their ends by adapted halves of a parabolic reflector

are connected and form a self-contained reflector. The interchangeability of the LED lamp or individual light ^¬ module and the handling of the LED lamp with reflector as a mounting unit will be according to another

Design of the lighting unit supported by a lenslet disc is releasably secured to the light exit side edge of the reflector. Such removable attachment of the lenslet to the edge of the reflector allows easy access to the light module (s) when replacement is required.

With reference to the drawings, the invention will be explained in more detail below. It shows:

Figure 1 is a mast light with a sectional Darge ^¬ presented lamp head. FIG. 2 shows a lighting unit in side view; FIG.

Fig. 3 is a section 111-111 of Fig. 2;

Fig. 4 is a scatter lens disc in section;

Fig. 5 is an end view V-V of Fig. 2;

6 shows a cooling body with light modules mounted on two carrier surfaces in plan view;

FIG. 7 shows the left side view VII from FIG. 6; FIG.

Fig. 8, the lower side view VIII of the heat sink

Fig. 6;

9 shows another embodiment of the heat sink in the

View of Fig. 8;

10 shows the heat sink of FIG. 6 to FIG. 8 in SD representation; FIG.

Fig. 11 in 3D representation of another heat sink with three support surfaces;

Fig. 12 in 3D representation of a heat sink with four

Surfaces;

Fig. 13 in 3D a heat sink with six

Surfaces;

FIG. 14 is an elongated illumination unit in front view ^¬ XIV of Fig. 15;

Fig. 15 is a section XV-XV of Fig. 14 with stepped

Scattering lens slice in section;

16 shows a 3D illustration of an elongate cooling body with two parallel support surfaces, on each of which a plurality of light modules are arranged;

FIG. 17 shows the illumination unit of FIGS. 14 and 15 without a lens plate in a 3D view.

In Fig. 1 is slightly simplified a mast light 1 Darge ^¬ represents. At the upper end of the mast 2, a lamp head 3 is fixed, in which a lighting unit 4 is housed with associated ballasts 5 and 6 and a diffuser lens 7 for illuminating a traffic area from about 5 m to 6 m height. The illustrated and described lighting unit 4 is shown here with two light modules

8 and 9, each having as light sources 11 several light ^¬ diodes (LED), which are arranged like a grid at small intervals on a flat side of a plate-shaped, good heat ^¬ conductive diode support 10 and a

form one-sided emitting light source 11. Although in the embodiments described herein, the light modules 8,

9 are each equipped with multiple LEDs, it is also conceivable to provide only one LED as a light source 11. The diode carrier 10 consists of a metal plate,

for example, aluminum or copper. In the in the FIGS. 2 to 9 show two such diode carriers 10 or light modules 8, 9, which are fastened to opposite carrier surfaces 12 and 13 of a wall-like carrier element 16 of a heat sink 14 with a certain contact pressure. In order to be able to generate this contact pressure, screws 15 are provided here by way of example as pressing means 15, which are arranged in two diametrically opposite corners of the approximately square diode supports 10 and screwed to a support element 16 of the cooling body 14.

The two mutually plane-parallel side surfaces of this support member 16 form the support surfaces 12 and 13, where the diode support 10 with the light modules 8,

9 are attached. In order to fix the light modules 8 and 9 respectively under a permanent contact pressure on the support surfaces 12 and 13, it is also possible, instead of here

For example, provided screws 15 other fastening ^¬ supply means through which the diode support 10 can be easily installed and replaced and the light modules 8.9 so far also with good thermal contact with the

Support surfaces 10 of the heat sink 14 are to be attached. The fastening means could for example consist of resilient clamps or the like .. To a good heat conduction connection between the diode carriers

10 and the carrier element 16, a paste-like heat-conducting layer 17 can be arranged between the diode carriers 10 and the carrier surfaces 12 and 13, respectively. As seen in Fig. 3 and Fig. 5 to Fig. 13, the heatsink 14 includes a support member 16 and a foot ^¬ part 19. The heat sink 14 in connection with the light sources 11, which in the exemplary embodiment as a light modules 8, 9 Mounted on diode carriers form the LED lamp (Figures 6, 7, 8, 9, 16).

The wall-like support element 16 in FIGS. 3 and Fig. 5 to Fig. 10 is disposed in the vertical plane of symmetry 18 of the heat sink 14, so that their two plane ^¬ parallel outer surfaces 12, 13 symmetrically opposite with respect to this plane of symmetry 18. The cooling body 14 is formed with its support surfaces 12 and 13 radially projecting cylindrical foot part 19 as a one-piece metal block, preferably made of aluminum. The transitions from the support surfaces 12, 13 to the upper end face 27 of the foot part 19 are each formed as concave curves to allow a better heat transfer.

The foot part 19 is provided on the underside with a flat planar circular base surface 20 which is perpendicular to the

Symmetry plane 18 runs. With this footprint 20, the heat sink 14 is heat-transmitting on a metal

Mounting plate 21 is mounted inside the lamp head 3.

In this case, to improve the heat transfer to the provided with a metal housing lamp head 3 also a WärmeleitSchicht 17 may be mounted on the base 20.

Analogous to conventional mast lights 1, the lighting unit 4 provided here also has a light-guiding device shaped in the manner of a parabolic mirror

Reflector 25 with an optical axis 26. This formed as a round shell body reflector 25 is provided with a cylindrical mounting collar 24 which is adapted to a cylindrical projection 23 of the heat sink 14 and secured thereto by means of screws. In this way, the reflector 25 forms together with the heat sink 14, a structural mounting unit, which as a whole in the

Simply install luminaire head 3 of the mast luminaire 1 and remove it. As best seen in FIGS. 3 and 5, this results in an arrangement of the diode carriers 10 with the light sources 11 at least approximately in the optical center of the reflector 25 formed as a parabolic mirror, so that the main beam direction of the reflector 25

reflected light of the light sources 11 within a predetermined opening angle substantially parallel to the optical axis 26 of the reflector 25 extends.

In order to avoid dazzling effects of the light 25 leaving the reflector of the light sources 11, it is due to the optical diffusing lens 7 on the surface to be illuminated

directed. Such lens discs 7 are known per se. The scattering lens 7 can directly on a Ringfalz, the light exit side final edge 29 of the

Reflector 25 forms, be attached. But it is also possible to attach this lens disc 7 by means of a flange 31 on a collar 30 of the lamp head 3. That this is a solvable

Fastening must act, arises from the need for interchangeability of the lighting unit 4 or the LED lamp or its light modules 8 and 9.

To the required for the light modules 8, 9 electrical connecting wires 69 (FIG. 16) through the heat sink 14th

to be able to pass, this is provided with at least two drilled, obliquely extending ducts 32 and 33 which extend between the lower lateral surface 19 'of the foot part and the upper, lying below the support surface 12 and 13 end face 27. The drilled ducts 32, 33 not only facilitate the laying of the

Connecting wires 69 by the shortest route, but also their sheltered housing.

9, an embodiment of a heat sink 14 is shown in which the opposing support surfaces 12 and 13 of the support member 16 is not parallel extend to each other and the plane of symmetry 18, but together form an acute angle a, which may be about 5 ° to 10 °. Such orientations of the support surfaces 12 and 13 may be used in conjunction with matched parabolic mirrors for other light distributions on the surface to be illuminated if required.

In the Fig. 11, Fig. 12 and Fig. 13 other execution ^¬ form of the heat sink 14 are provided. In this case, the heat sink 14 of FIG. 11 is provided with a three-sided support member 16, which offers the possibility to attach to the three carrier ^¬ surfaces 36, 37 and 38 each light modules 8, 9. Incidentally, the structure and arrangement of the heat sink 14 in the reflector 25 is at least approximately the same as the heat sink 14, so that reference is made in this regard to the above explanations.

FIG. 12 shows a heat sink 14 with a square carrier element 16, which has four carrier surfaces 41, 42, 43 and 44. In these two heat sinks 14, the support surfaces 36, 37, 38 and 41, 42, 43, 44 as in the above-described wall-type heat sink 14th

arranged symmetrically to an axis of symmetry 18, wherein the support surfaces 36, 37 and 38 and 41,42, 43 and 44 of both illustrated carrier elements 16 are arranged in the manner of a regular polygon concentric to the axis of symmetry 18 of the heat sink 14 and to the optical axis 26 of the reflector 25 or can be.

13 shows that the cooling body 14 with six axes ^¬ parallel support surfaces 51 to 57 of a hexagonal

Carrier element 16 may be provided, wherein the abutting edges of the support surfaces 51 to 57 lie on a circle and thus can form the sides of a regular hexagon. In the illustrated embodiment, however, the two opposing support surfaces 51 and 54 are wider than the remaining support surfaces 52, 53, 56, 57, respectively have shorter side lengths.

This is to show that the basic structure of the cooling ^¬ body 14 allows many variants.

In Figs. 14 to 17 inclusive is a

Embodiment as a further design option is ^¬ provided, in which a reflector 25 is provided, which consists of two equal length parabolic curved reflector halves 62, 63 which are symmetrical to a common

Symmetrieebene 61 are arranged and extend along this plane of symmetry 61. Here are the two

Reflector halves 62 and 63 at their ends by matched halves 64 and 65 of a paraboloidal shaped reflector gapless connected together so that they form the self-contained reflector 25, as shown in Figs. 14, Fig. 15 and Fig. 17.

The ends of the two elongate reflector halves 62 and 63 are indicated by dotted lines 66 and 66. Between these two lines 66 and 67 extends an elongated carrier element 16 of a heat sink 14, which is likewise provided with a laterally projecting foot part 19. As is apparent from Fig. 16, the ends of the foot part 19 are each provided with semicircular rounding.

The mutually plane-parallel side surfaces of the support element 16 each form a support surface 12 and 13, respectively.

The foot part of the heat sink 14 is also provided with a surface 23 having a ring ^¬ approach 23.

By means of a fastening collar 24, the reflector 25 on the projection 23 of the heat sink 14 in a similar manner

attached as the round reflector 25 is attached to one of the heat sink 14 or can be. At the two mutually opposite support surfaces 12 and 13 of the support member 16 each have a plurality of light modules 8 and 9 are arranged as described above. To make this clearly visible, the heat sink 14 is shown in Fig. 16 as a single part standing on its base 20.

In Fig. 16, the cable channels 33 are shown, through which the electrical connections 69 to the individual

Light modules 8, 9 are guided. By means of connecting lines 70, the light modules 8, 9 shown visibly in FIG. 16 are each connected to the light modules 8 arranged on the opposite support surface 12 in the form of a series connection.

In Fig. 15 the reflector lens 25 is also shown in sectional view to the lens 25 7, which can be fastened in a suitable manner to a circumferential annular fold on the light exit side edge 29 of the reflector 25. However, the diffusing lens 7 can be arranged and fixed functionally in other ways.

LED lamp and lighting unit using the same

LIST OF REFERENCES 1 mast light

2 mast

3 lamp head

4 lighting unit

5, 6 ballast

7 scattered lens disc

8.9 light modules

10 diode carriers

11 light source

12,13,36-38,41-44,51-57 support surface

14 heat sink

15 contact pressure, screw

16 sponsorship

17 thermal conductivity layer

18 symmetry plane of the heat sink

19 foot part

20 floor space

21 mounting plate

23 approach

24 fastening collar

25 reflector

26 optical axis

27 face

29 edge

30 ring collar

31 flange ring

32, 32 cable channels

62-65 reflector halves

66.67 lines dotted lines

69 connecting wires

73 ring surface

Claims

1 LED lamp and lighting unit using the same claims

1. LED lamp for use in a lighting unit, with at least one LED as the light source (11) and with a heat sink (14) of heat-conducting material for dissipating by a light source (11) generated heat, wherein the

Heatsink (14) has at least one support surface (12,13,36-38,41- 44,51-57), on which said light source (11) is heat-transfer-attached, characterized in ^¬ net, that the support surface (12,13, 36-38, 41-44, 51-57) is part of a support element (16) of the heat sink (14) and the heat sink (14) further comprises a foot part (19) for mounting the LED light in a lighting unit, wherein the Support surface (12,13,36-38,41-44,51-57) and an adjacent surface of the foot part (19) are at an angle to each other and the transition between the two surfaces is continuous everywhere.

2. LED lamp according to claim 1, characterized in that the support surface (12,13,36-38,41-44,51-57) and an adjacent surface of the foot part (19) at an angle in the range between 90 ° and 135 ° to each other.

3. LED lamp according to claim 1 or 2, characterized

characterized in that the cooling body (14) is integrally formed.

4. LED lamp according to claim 3, characterized

in that the heat sink (14) is formed from a machined continuous casting profile. 2

5. LED lamp according to one of the preceding claims, characterized in that the light source (11) interchangeable means of releasable contact pressure means (15) on a support surfaces (12,13,36-38,41-44,51-57) is mountable.

6. Lighting unit, in particular for a stationary luminaire for illuminating a larger area, with an LED lamp whose light source (11) is arranged at least approximately in the optical center of a parabolic mirror shaped reflector (25) of the lighting unit, so that the main beam direction of from the reflector (25) reflected light of the light source (11) substantially parallel to the optical axis (26) of the reflector (25) extends, characterized in that the LED lamp is designed according to one of claims 1 to 5.

7. Lighting unit according to claim 6, characterized in that the cooling body (14) at its foot part (19) has a plane-flat base (20), with which the heat sink (14) heat transfer to a

Frame part of a lamp housing of a lamp is mounted.

8. Lighting unit according to claim 6 or 7, characterized in that the reflector (25) is releasably secured to the heat sink (14) and forms with this a structural mounting unit.

9. Lighting unit according to one of claims 6 to 8, characterized in that a scatter lens ^¬ disc (7) is releasably attached to the light exit side edge (29) of the reflector (25).