EP2439445B1 - LED light with curved light emission area - Google Patents

Description

The invention relates to a luminaire having a first LED (LED: light-emitting diode) and a second LED, wherein the first LED and the second LED form parts of a light source of the luminaire, as well as with a circuit board arrangement, wherein the first LED and the second LED are arranged on the board arrangement. Moreover, the invention relates to a heat sink for such a lamp.

Such a luminaire is known from the prior art, which has a rectilinearly shaped light emission region. However, with the luminaire it is not possible to produce a light emitting area that appears curved or curved.

From the DE 10 2009 009 288 A1 an LED array with a rigid-flexible support plate according to the features of the preamble of claim 1 is known, having rigid support areas, on each of which an LED is arranged. The rigid support areas are connected to each other by an existing therebetween flexible, thinner support area.

From the DE 20 2008 007 490 U1 For example, a lighting device with an annular support is known, on which substrates with LEDs are arranged. The light emitted by the LEDs is deflected over a reflective surface and then emitted by the illumination device to the outside.

From the US 4,422,134 a luminaire with an annular housing is known. The light source used lamps, which are arranged in the center of the housing. The light emitted by the lamps is redirected by a reflector.

The invention has for its object to provide a corresponding lamp that offers improved design options with respect to the shape of the light emitting area of the lamp. In addition, a heat sink for such a lamp should be specified.

This object is achieved with the objects mentioned in the independent claims. Particular embodiments of the invention are indicated in the dependent claims.

According to the invention, there is provided a luminaire having a first LED and a second LED, the first LED and the second LED forming parts of a light source of the luminaire; Furthermore, the luminaire has a board arrangement, wherein the first LED and the second LED are arranged on the board arrangement. The board assembly has a first plate-shaped portion with a first plane surface area on which the first LED is arranged and fixed by a first surface normal, and a second plate-shaped portion with a second planar surface area on which the second LED is arranged and by which a second surface normal is defined; In this case, one or the angle between the first surface normal and the second surface normal is greater than 0 ° and smaller than 180 °.

Such a configuration of the board arrangement makes it possible to generate a light output along a curved or curved line.

According to the invention, the first plate-shaped section and the second plate-shaped section are formed integrally. In this way, the production of the lamp is possible in a simplified manner. If the board arrangement in this case has printed conductors which are designed both for the power supply of the first LED, and for the power supply of the second LED, soldering of individual boards by means of wires can be avoided, so that the production is made possible in a further simplified manner.

According to the invention, the first plate-shaped portion and the second plate-shaped portion are connected via a bend, by which a bending straight line is defined. As a result, a particularly simple production is possible. The preparation of the bend is thereby further facilitated if the board assembly along the bend has a material-reduced region whose thickness is less than a thickness of the first plate-shaped portion and less than a thickness of the second plate-shaped portion.

Further advantageously, the board arrangement has at least one further plate-shaped section with at least one further planar surface area, on which at least one further LED is arranged and by which at least one further surface normal is defined, wherein the at least one further plate-shaped section and the first plate-shaped section or the at least one further plate-shaped portion and the second plate-shaped portion are connected via a further bend, by which a further bending straight line is defined. As a result, the production is possible further simplified. In terms of manufacturing technology, the further bending straight line is oriented parallel to the first-mentioned bending straight line. By using correspondingly many LEDs as the light source of the luminaire, the luminaire can be so designed make that with her in principle an arbitrarily long, curved appearing light output can be generated.

A particularly uniform light emitting area can be achieved if the first LED and the second LED and the at least one further LED are arranged such that they pass through a circular line or an ellipse line. Preferably, the LEDs are arranged in equidistant manner. By such equidistant arrangement of the LEDs, the homogeneity of the light emission phenomenon can be increased further.

According to the invention, the luminaire further comprises a reflector which is designed and arranged such that it deflects a light emitted by the first LED and the second LED in a direction which is oriented parallel to the bending straight line. As a result, overall a light output of the lamp can be generated, which is less dependent on the viewing angle.

The board arrangement advantageously has an annular structure, preferably a closed-ring-shaped structure, for example a circular structure.

The board arrangement advantageously consists of one board or several boards; Preferably, it comprises or consists of at least one bendable metal core board.

Preferably, the first LED is configured to emit light having a first wavelength spectrum and the second LED is configured to emit light having a second wavelength spectrum different from the first wavelength spectrum.

According to a further aspect of the invention, a heat sink for a luminaire according to the invention is provided, which has a first plane surface area which is intended to be thermally conductively connected to the first plate-shaped section of the board arrangement and a second plane surface area provided for this purpose is to be thermally conductively connected to the second plate-shaped portion of the board assembly.

Preferably, the heat sink has an annular structure. As a result, it is particularly suitable for the case in which the luminaire has a correspondingly annular light exit region, that is to say, for example, an annular light exit region. Advantageously, the heat sink is composed of one or more segments, for example, between two and eight, segments. This makes it possible to avoid having to manufacture a separate heat sink for each of the LEDs and correspondingly arrange them separately.

Particularly advantageously, the heat sink is configured in such a way that the first plane surface area and the second plane surface area are formed with respect to the annular structure facing outward. This embodiment is particularly suitable for the case that the lamp has an annular light exit area. However, it can also be provided that the heat sink is configured such that the first plane surface area and the second plane surface area are formed with respect to the ring-shaped structure pointing inwards.

The lamp according to the invention advantageously has a heat sink according to the invention, wherein the heat sink is thermally conductively connected to the first LED and the second LED.

Fig. 1

eine skizzierte Ansicht eines Ausführungsbeispiels einer erfindungsgemäßen Leuchte von schräg oben,

Fig. 2

eine entsprechende Ansicht von schräg unten,

Fig. 3

eine Skizze durch die aufgeschnittene Leuchte,

Fig. 4

eine Querschnitt-Skizze der Leuchte,

Fig. 5

eine Skizze der Platinen-Anordnung der Leuchte ,

Fig. 6

eine Skizze zu einem Detail aus Fig. 5,

Fig. 7

eine Skizze der Platinen-Anordnung, bevor diese in ihre vorgesehene Form gebracht worden ist,

Fig. 8

eine perspektivische Skizze des Kühlkörpers der Leuchte,

Fig. 9

eine Skizze einer Schnittdarstellung durch den Kühlkörper,

Fig. 10

eine Skizze einer Schnittdarstellung durch eine Variante des Kühlkörpers,

Fig. 11a

eine perspektivische Sicht einer erfindungsgemäßen Leuchte in Form einer Pendelleuchte von schräg unten,

Fig. 11b

eine entsprechende Sicht von schräg oben und

Fig. 12

eine perspektivische Sicht einer erfindungsgemäßen Leuchte in Form einer Deckeneinbauleuchte von schräg unten.

The invention is explained in more detail below with reference to exemplary embodiments and with reference to the drawings. Show it:

Fig. 1

a sketched view of an embodiment of a lamp according to the invention obliquely from above,

Fig. 2

a corresponding view from diagonally below,

Fig. 3

a sketch of the cut-open lamp,

Fig. 4

a cross-sectional sketch of the luminaire,

Fig. 5

a sketch of the board arrangement of the luminaire,

Fig. 6

a sketch to a detail Fig. 5 .

Fig. 7

a sketch of the board arrangement before it has been brought into its intended form,

Fig. 8

a perspective sketch of the heat sink of the luminaire,

Fig. 9

a sketch of a sectional view through the heat sink,

Fig. 10

a sketch of a sectional view through a variant of the heat sink,

Fig. 11a

a perspective view of a lamp according to the invention in the form of a pendant lamp obliquely from below,

Fig. 11b

a corresponding view from diagonally above and

Fig. 12

a perspective view of a lamp according to the invention in the form of a ceiling light from diagonally below.

The FIGS. 1 to 4 show an embodiment of a lamp according to the invention in different representations; Fig. 1 shows a perspective view obliquely from above, Fig. 2 a perspective view obliquely from below, Fig. 3 a representation of the cut lamp and Fig. 4 a cross-sectional view.

As in Fig. 2 indicated in sections, can be generated with the light a curved or bent light emitting area 3. For example, as in the exemplary embodiment shown, the case may be provided a light output region 3 which appears to be circular overall.

The luminaire has a - in the Figures 3 and 4 designated - board assembly 6, in perspective in separated form in Fig. 5 is shown.

The lamp also has a light source, wherein one, in Fig. 5 designated, first LED 2 and a second LED 4 parts of the light source form. The first LED 2 and the second LED 4 are arranged on the board assembly 6.

A section of the board arrangement 6 around the two mentioned LEDs 2, 4 is in Fig. 6 sketched in enlarged form. The circuit board arrangement 6 has a first plate-shaped region 8, which has a first planar surface region 82, wherein the first LED 2 is arranged on the latter. The first planar surface region 82 defines a first surface normal N1 . In addition, the board arrangement 6 has a second plate-shaped region 10, which has a second planar surface region 102, wherein the second LED 4 is arranged on the latter. The second planar surface region 102 defines a second surface normal N2 . The design is such that the angle W between the first surface normal N1 and the second surface normal N2 is greater than 0 ° and smaller than 180 °. For example, the angle W can be between 2 ° and 178 °.

In other words, the first planar surface region 82 extends in a first plane and the second planar surface region 102 extends in a second plane, which is not oriented parallel to the first plane.

As a result of this configuration, it is possible in an advantageous manner in terms of manufacturing technology for the first LED 2 to be able to emit light in the direction of the first surface normal N1 and for the second LED 4 to emit light in the direction of the second surface normal N2. In this way, using a further LED, which are arranged in an analogous manner as further parts of the light source of the luminaire on corresponding further sections of the circuit board arrangement 6, a light emission area can be effected, which overall appears curved or arched.

For example, consider - as in Fig. 6 indicated - the board assembly 6 from a direction P, which is oriented both normal to the first surface normal N1 and normal to the second surface normal N2 and which lies in the plane of the first planar surface region 82, that of the LEDs emitted light along a curved line, which is defined by the corresponding plate-shaped portions of the board assembly 6.

For example, can be - according to the sketches from the Figures 2 and 5 - Using multiple or many LEDs to realize the total circular appearing Lichtabstrahlbereich 3 by the circuit board assembly 6 circular designed and thereby so that for each of the LEDs in each case a corresponding plate-shaped area is provided with a corresponding planar surface area on which the LED is arranged.

For example, the angle W may be between 2 ° and 25 °, in particular between 5 ° and 10 °. The light output region 3 can be made to appear particularly uniform appearing by multiple or many LEDs are used and the respective angle W is chosen to be the same size for two immediately adjacent the LEDs. The LEDs are preferably mounted in equidistant arrangement on the board assembly 6.

Obviously can be realized by the embodiment shown in principle arbitrarily shaped and arbitrarily long light output ranges, so for example circular, circular segment-shaped, elliptical or S-shaped curved light emitting areas. In this case, it is advantageous, for example, to realize a circular light emission region, to configure the printed circuit board assembly 6 in such a way that it has an annular structure, preferably a closed-ring-shaped structure.

As in Fig. 6 sketched by way of example, the board assembly 6 is advantageously designed such that the first plate-shaped portion 8 and the second plate-shaped portion 10 are formed integrally. In other words, advantageously, the first plate-shaped portion 8 and the second plate-shaped portion 10 are made of one piece or integrally formed. As a result, the production of the lamp is facilitated, since in particular a corresponding handling of several individual boards is not required.

In particular, the board assembly 6 may be designed such that there are applied to it conductor tracks, which are designed both for powering the first LED 2 and for powering the second LED 4. In this way, a soldering of wires between the first portion 8 and the second portion 10 can be saved. In the case of more than two LEDs, a corresponding soldering to a chain of individual boards can be avoided.

A particularly simple production is made possible when the first section 8 and the second section 10 are connected by a bend, by means of which a bending straight line G1 is defined. The bend can be formed by kinking along the straight line G1 . The production of the bend is further facilitated if the board assembly 6 along the bend has a material-reduced area 810 whose thickness is less than a thickness of the first plate-shaped portion 8 and less than a thickness of the second plate-shaped portion 10. In particular generate quasi a desired bending line by such a material-reduced area 810, which simplifies the production. Such a material-reduced area can be formed for example by a Hinterfräsen. In particular, the board assembly 6 may be formed of a linear shape as shown in FIG Fig. 7 shown by corresponding bends very easy in the desired intended shape, as exemplified in Fig. 5 shown to be brought.

As in Fig. 6 sketched and already indicated above, the lamp may further comprise a third LED 14 and the board assembly 6 while a third plate-shaped portion 12 having a third planar surface area 122, through which a third surface normal N3 is fixed, wherein the third LED 14 on the third planar surface area 122 is arranged. The third LED 14 may also be part of the light source of the lamp in particular. In particular, further LEDs may be provided in an analogous form, ie at least four or at least five LEDs, so that more generally the luminaire may have at least one further LED 14 and the board arrangement 6 at least one further plate-shaped section 12 with at least one further plan Surface area 122, is defined by the at least one further surface normal N3 , wherein the at least one further LED 14 is disposed on the at least one further surface region 122. The at least one another LED 14 may also be part of the light source of the lamp. By using correspondingly many LEDs, it is thus possible to form a generally curved or curved luminous structure of arbitrary length.

In this case, a connection between the at least one further plate-shaped section 122 and the first plate-shaped section 8 or the second plate-shaped section 10 may be designed analogously to the connection between the first section 8 and the second section 10. In this case, in particular, a further bend may be provided be set by a further bending straight line G2 , wherein the embodiment is preferably such that the further bending straight G2 is oriented parallel to the first-mentioned bending straight line G1 ; In this way, the production is further simplified. In addition, the LEDs 2, 4, 14 can be arranged in such a way that they have a, in Fig. 4 exemplarily sketched, level E prevail.

For example, the luminaire may be designed such that the first LED 2 and the second LED 4 and the at least one further LED 13 are arranged such that they pass through a circular line or an ellipse line.

In terms of manufacturing technology, the board arrangement 6 consists of a board, in particular of a bendable metal core board. But it may also have a plurality of boards, which are composed so to speak for shaping the light emitting area to a chain, each of the plurality of boards advantageously has at least two plate-shaped portions in the manner of the first plate-shaped portion 8 and the second plate-shaped portion 10.

Preferably, the luminaire further comprises, by way of example in FIG Fig. 4 Reflector 15, which is designed and arranged so that it deflects a light emitted from the first LED 2 and the second LED 4 light in a direction L , which is oriented parallel to the bending line G1 . In particular, the embodiment may be such that the direction L is normal to the plane E , in which the LEDs 2, 4, 14 are arranged.

By such a reflector 15 can be achieved in particular that a light output of the lamp appears less dependent on the viewing direction of a viewer. Preferably, the reflector 15 thereby - as exemplified in Fig. 4 shown - with respect to the first LED 2 a concave curvature. This is based on the Fig. 6 explained in more detail. As shown above, a viewer who looks at the board assembly 6 in the direction P will generally see a bent light emitting area or a correspondingly shaped light line pattern composed of individual light spots of the LEDs 2, 4, 14. However, with a comparatively small change in the viewing angle, it is possible for a light emitted by the first LED 2 to be shaded by the first section 8. Of course, this also applies to all other LEDs 4, 14. In this case, a viewing in the direction P is particularly advantageous if the LEDs 2, 4, 14 are arranged in the plane E , because the obtained curvature appears maximum under this line of sight. By using the reflector 15, a light emitted by the LEDs 2, 4, 14 can be redirected, so that such shading by one of the plate-shaped sections 8, 10, 12 of the board arrangement 6 can be avoided. In this way, the dependence of the appearance of the light output is reduced from the viewing direction.

In the example shown, the reflector 15 is formed analogous to the board assembly 6, here so circular.

The light can be - exemplarily in Fig. 4 have light exit region 152 through which a light emitted by the first LED 2, the second LED 4 and possibly the at least one further LED 14 light leaves the light. In particular, the light exit region 152 may be shaped such that it forms or forms the light emission region of the luminaire. It can be provided that the lamp is designed such that the light after interacting with the reflector 15, the light without further interaction with another optically active element of the light passes through the light exit region 152 and leaves the light. In this case, the light exit region 152 can in particular be formed in a further plane E2 , which is parallel to the plane E, in which the LEDs 2, 4, 14 are arranged. In this case, it can further be provided that, in the case of an alignment of the luminaire intended for operation, the plane E2 of the luminaire Light exit region 152 is oriented horizontally. In particular, it may be in this case - as in the FIGS. 11a and 11b indicated - to act a pendant light or - as in Fig. 12 indicated - to act a recessed ceiling light. It may also (not shown in the figures) to act a ceiling mounted luminaire.

In order to further reduce the dependence of the light phenomenon, the luminaire may further comprise a cover member 154 arranged so that it is normal to the plane E2 or normal to the plane E or in a direction parallel to the plane when viewing the lamp Direction P all LEDs 2, 4, 14 hidden or covered. In this way it can be achieved that when viewing the lamp none of the LEDs 2, 4, 14 can be seen directly. This further contributes to the fact that the light output range appears particularly homogeneous.

If it is provided that the first LED 2 is designed to emit light having a first wavelength spectrum and the second LED 4 is configured to emit light having a second wavelength spectrum that differs from the first wavelength spectrum, the embodiment shown within can the lamp cause an advantageous mixing of a light of the first LED 2 with a light of the second LED 4, so that a viewer perceives the light emitting area appearing particularly homogeneous. For example, it can be provided that the first LED 2 generates light in a first "white tone" and the second LED 4 generates light in a second "white tone".

For effective dissipation of heat, which may arise during operation by the first LED 2 and the second LED 4 and optionally the at least one further LED 14, a heat sink for the luminaire is advantageously provided.

Fig. 8 shows by way of example a perspective sketch of a corresponding heat sink 16. The heat sink 16 may be provided in particular for passive cooling. The heat sink 16 has a first planar surface region 20, which is intended to be thermally conductively connected to the first plate-shaped section 8 of the board arrangement 6, and a second planar surface region 22, which is provided therewith, to the second plate-shaped section 10 the circuit board assembly 6 to be thermally conductively connected.

In terms of manufacturing technology, the first planar surface region 20 of the heat sink 16 directly adjoins the second planar surface region 22, preferably with the formation of an edge which-in the state of the heat sink 16 installed in the light-is oriented parallel to the bending straight line G1 .

In the exemplary embodiment shown, the heat sink 16 has an annular structure. This embodiment is suitable for use with a corresponding annularly shaped circuit board arrangement 6 for realizing a circular light exit region 152 or light emission region.

Analogously to the configuration of the board arrangement 6, the cooling body 16 can accordingly have at least one further planar surface region 24, which is intended to be thermally conductively connected to the at least one further plate-shaped section 12 of the board arrangement 6.

As exemplified in Fig. 8 The first planar surface region 20, the second planar surface region 22 and optionally the at least one further planar surface region 24 are furthermore preferably arranged in a plane E. How out Fig. 4 As can be seen, in the state of the heat sink 16 incorporated in the luminaire, this last plane E can be, in particular, that plane E in which the LEDs 2, 4, 14 are arranged.

As exemplified in Fig. 9 shown, the heat sink 16 is advantageously made of a segment 161. This eliminates the requirement corresponding to many individual heatsink. Alternatively, as in Fig. 10 outlined, the heat sink 16 may be made of multiple segments 162, 164, 166. For example, the cooling body 16 may be composed of two, three, four, five or six or even more segments, wherein preferably each of the segments each has at least two planar surface regions, which are designed analogously to the first and the second planar surface region 20, 22.

In the example shown, the heat sink 16 is configured such that the first planar surface region 20 and the second planar surface region and optionally the at least one further planar surface region 24 with respect to the annular structure are formed facing outward. In this case, the heat sink 16 advantageously has cooling ribs 168 which point inward with respect to the annular structure. In this case, the embodiment is preferably such that the cooling fins 168 extend over the entire vertical extension of the heat sink 16 in the case of a horizontal orientation of the annular structure. The orientation of the cooling fins 168 and their distances are advantageously designed for the thermally optimal operation.

Alternatively, however, (not shown in the figures), the configuration may be such that the first planar surface region and the second planar surface region and optionally the at least one further planar surface region are formed facing inwardly with respect to the annular structure.

Claims (12)

1. Light, having

   - a first LED (2) and

   - a second LED (4), wherein the first LED (2) and the second LED (4) form parts of a light source of the light, as well as

   - a circuit board arrangement (6), wherein the first LED (2) and the second LED (4) are arranged on the circuit board arrangement (6), wherein the circuit board arrangement (6) has a first plate-shaped section (8) with a first plane surface area (82) on which the first LED (2) is arranged and by which a first surface normal (N1) is defined, and a second plate-shaped section (10) with a second plane surface area (102) on which the second LED (4) is arranged and by which a second surface normal (N2) is defined, wherein an angle (W) between the first surface normal (N1) and the second surface normal (N2) is greater than 0° and less than 180°, wherein the first plate-shaped section (8) and the second plate-shaped section (10) are formed contiguously, wherein the first plate-shaped section (8) and the second plate-shaped section (10) are connected via a curve by which a curve straight (G1) is defined, characterized in that

   - a reflector (15), designed and arranged in such a way that it diverts a light emitted by the first LED (2) and the second LED (4) into a direction (L) is oriented parallel to the curve straights (G1).
2. Light according to claim 1, where the circuit board arrangement (6) has conductor paths designed for supplying the first LED (2) and the second LED (4) with power.
3. Light according to one of the preceding claims, where the circuit board arrangement (6) has alongside the curve a material-reduced area (810) whose thickness is less than a thickness of the first plate-shaped section (8) and less than a thickness of the second plate-shaped section (10).
4. Light according to one of the preceding claims, where the circuit board arrangement (6) has at least one further plate-shaped section (12) with at least one further plane surface area (122) on which at least one further LED (14) is arranged and by which at least one further surface normal (N3) is defined, wherein the at least one further plate-shaped section (12) and the first plate-shaped section (8) or the at least one further plate-shaped section (12) and the second plate-shaped section (10) are connected via a further curve by which a further curve straight (G2) is defined, wherein preferably the further curve straight (G2) is oriented parallel to the curve straights (G1) mentioned first.
5. Light according to claim 4, where the first LED (2) and the second LED (6) and the at least one further LED (14) are arranged in such a way that they cross a circular line or an ellipse line, wherein the LEDs (2, 6, 14) are preferably arranged in an equidistant manner.
6. Light according to one of the preceding claims, where the circuit board arrangement (6) has a ring-shaped structure, preferably a closed ring-shaped structure.
7. Light according to one of the preceding claims, where the circuit board arrangement (6) consists of a circuit board or of several circuit boards and preferably comprises at least one bendable metal core circuit board.
8. Light according to one of the preceding claims, where the first LED (2) is configured to emit light with a first wavelength spectrum and the second LED (4) is configured to emit light with a second wavelength spectrum differing from the first wavelength spectrum.
9. Cooling body with a light according to one of the preceding claims, having

   - a first plane surface area (20), provided for being connected in a thermally conductive manner with the first plate-shaped section (8) of the circuit board arrangement (6), and

   - a second plane surface area (22), provided for being connected in a thermally conductive manner with the second plate-shaped section (10) of the circuit board arrangement (6).
10. Cooling body with a light according to claim 9, having a ring-shaped structure and at the same time preferably being made up of a segment (161) or of several segments (162, 164, 166).
11. Cooling body with a light according to claim 10, where the first plane surface area (20) and the second plane surface area (22) are designed pointing outwards with respect to the ring-shaped structure, or where the first plane surface area (20) and the second plane surface area (22) are designed pointing inwards with regard to the ring-shaped structure.
12. Cooling body with a light according to one of the claims 9 to 11, wherein the cooling body (16) is connected with the first LED (2) and the second LED (4) in a thermally conductive manner.

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