DE102010051841B4 - LED insert for lights - Google Patents

Abstract

Luminaire insert comprising: - a heat sink (4); - An LED chip (6) arranged on the heat sink (4); - A front screen (1), which is designed to fix the lamp insert in a lamp; and - a plurality of guide rails (7) by means of which the heat sink (4) is fastened to the windscreen (1).

Description

The invention relates to an LED insert for lights, especially for lights with a QR-70 and / or / QR-111 recording.

Halogen bulbs, such as are commonly used in QR-70 and / or QR-111 lights, for example, have a variety of disadvantages compared to LED bulbs, such as the shorter life and thus required, high AC frequency. Another advantage of LED bulbs is the comparatively low energy consumption, ie the high light output.

So far, in the area of lighting for the use of LEDs as energy-efficient, more economical light source for luminaires with QR-70 and / or QR-111 inserts, it is possible to replace the complete luminaire with another, with LED-equipped luminaire. Since the luminaires usually differ in the installation dimensions, one must dispose of the previous luminaires and can, for example, only select in a limited selection of LED luminaires.

LED lamps are available on the market that fit into QR-70 and / or QR-111 inserts, but these bulbs have the disadvantage that the compact design favors increased heat development and thus the lifetime can be severely limited. In addition, for example, the performance or light color can not meet the requirements. In addition, only a very limited selection of light angles is possible with these bulbs. The compact design makes increased demands on disposal, since the individual components are disposed of together and can only be disassembled into the individual recyclable components by additional effort. Many interested parties therefore reject the idea of retrofitting the lighting with the currently energy-efficient and ecologically sustainable lighting technology using LEDs.

EP 1 890 076 A1 describes a light emitting device that can accommodate a widening or narrowing of an illuminated area, thereby directing approximately all of the light emitted by an LED into the illuminated area. In this case, an optical unit, which receives light emitted by a LED in a large radiation angle range and emits a light via a front surface, can be displaced relative to the LED, whereby the illuminated area is widened or narrowed.

Object of the present invention is to make the LED technology in a cost effective very flexible manner a variety of lighting systems, especially lights with QR-70 and / or QR-111 sockets accessible. This object is achieved by a luminaire insert with the features specified in claim 1. Preferred embodiments are subject of the dependent claims.

Thus, in particular, the invention provides a luminaire insert comprising an LED chip and a heat sink on which the LED chip is mounted. Depending on the field of application, the LED chip can be designed for different light outputs and is matched in particular to the required luminous flux or the required radiant power. In order to keep the LED chip within a suitable operating temperature, the heat sink is tuned to the performance of the LED chip, in particular its generated heat output. In addition, the luminaire insert comprises a front module, which comprises a front screen and a plurality of guide rails. In particular, the front screen has a front side (front surface) and a rear side (rear surface).

While the front of the windscreen preferably at least partially forms a visible surface of the lamp insert, which is visible in particular from the front of the intended use of the lamp insert in a corresponding light from the outside, the back of the front window is facing away from the visible side or front. The guide rails are in particular arranged such that their attachment, in particular their attachment to the windscreen is not visible from the front. Particularly preferably, the guide rails are attached to the back of the windshield, which provided fasteners are not visible from the front. Particularly preferably, the guide rails or at least parts thereof (eg threaded bolts onto which a sleeve with internal thread is screwed) are glued and / or soldered and / or welded to the rear side of the front screen. This can be a fixture that is not visible on the front of the windscreen.

While using thermal radiators, such. B. halogen lamps, light is emitted in all directions, the light emission takes place, for example, of the LED chip contained in a luminaire insert according to the invention predominantly in the forward direction, ie away from the heat sink, approximately hemispherical or an opening angle of about 120 ° with the edge towards at least slightly decreasing intensity. It is thus no longer required by the use of a LED chip instead of a halogen bulb backward radiated light, for example, by a reflector that would have to extend beyond the bulb to steer forward. Thus, the luminaire insert according to the invention get by a relatively small installation depth. On the other hand, in an LED chip, unlike a halogen bulb, much of the resulting thermal energy is not radiated with the visible light. In order to increase its luminous efficiency and lifetime, the LED chip is cooled depending on its performance by means of the heat sink. The installation depth saved in a luminaire insert according to the invention in comparison to conventional halogen illuminants by dispensing with a reflector which extends, in particular, beyond the light source is preferably used at least partially for the cooling element for the LED chip directly behind the LED chip to arrange. Overall, thus a comparable installation depth can be achieved as in conventional halogen inserts, which is why the luminaire insert according to the invention is preferably adaptable to all common lights, in particular with QR-70 and / or QR-111 version.

Preferably, the windscreen is annular, wherein the windscreen has a light passage opening through which the light of the LED chip can pass. In particular, by the appropriate choice of the shape and size of the windscreen, the light insert is adaptable to the desired application, in particular all common people with QR-70 and / or QR-111 version.

Preferably, a lens is arranged in the light passage opening of the front screen. In this way, the light emitted by the LED chip can be influenced with regard to the emission angle. Depending on the field of application, the lens, in particular its size and / or focal length, is matched to the size of the luminaire in which the luminaire insert is to be used, ie. H. it is selected the appropriate lens and inserted into the light passage opening. Thus, a uniform radiation in the desired solid angle can be achieved.

Preferably, a mechanism (adjustment mechanism) is provided, which allows a continuous adjustment, in particular a stepless setting or returning the lens relative to the LED chip. Thus, the adjustment mechanism allows infinite variation or adjustment of a desired radiation angle of the emitted light amount. In particular, the adjustment mechanism allows stepless displacement or displacement of the heat sink with the LED chip arranged thereon relative to the front module, in the front pane of which the lens is arranged. Particularly preferably, the guide rails act as a guide for the displacement or displacement. The heat sink is preferably guided slidably on the guide rails. Thus, a forward or backward movement of the heat sink is possible relative to the guide rails and thus relative to the front module, while the heat sink is supported in sideways directions of the guide rails. For this purpose, recesses or feedthroughs, in particular bores, can be provided in the heat sink, through which the guide rails extend or which at least partially surround the guide rails.

Preferably, the heat sink on cooling fins, between which extend the guide rails and with which the heat sink at least partially abuts the guide rails or can rest and is guided in a sliding manner. This allows many available heatsink can be used without having to make appropriate recesses or holes. Although it is advantageous but not essential that the heat sink permanently rests against the guide rails or touches them. Instead, a gap between the cooling fins could also be greater than the extent or the cross section of the guide rails, so that at least a small movement of the heat sink relative to the guide rails in at least one direction transversely (laterally) to the displacement or displacement direction is possible , But it is at least advantageous if the running between the cooling fins guide rails at least partially stabilize the position of the heat sink, in particular against complete rotation of the heat sink about an axis parallel to the displacement direction, in particular an optical axis of the lens.

Preferably, a luminaire insert according to the invention permits a separate replacement of the LED chip and the heat sink and a complete reuse of a luminaire housing, in particular a complete reuse of the front module. The invention, in particular in the embodiments described in the claims and as described below by way of example, makes it possible to equip existing QR-70 and / or QR-111 inserts with LEDs as well as to equip new lights of this or similar type with LEDs.

An advantage of the invention is, inter alia, that the modular structure of the individual components LED chip, power supply and heat sink can achieve a maximum life of all components. It is also advantageous that the LED chip can preferably be exchanged individually. As a result, later improved LED developments can be retrofitted. It may be advantageous for this purpose that a continuously adjustable light angle and a maximum light output can be achieved by means of suitable lenses. It may also be advantageous that the heat sink is dimensioned very generously so that a maximum cooling effect and thereby a maximum life of the LED chip is achieved It may also be mentioned as advantageous that the components can be disposed of individually in the event of a defect, therefore a lesser effort in the recycling arises and still flawless components can be reused.

In summary, the invention thus provides a luminaire insert such that an adapted to the required luminous flux LED chip is mounted on a matched to the performance heat sink and by means of an adapted front module consisting of windscreen and guide rails on all popular lights with QR-70 / QR-111 -Fitting is adaptable, with no fastener is visible from the front.

Preferably, a mechanism allows the forward and back of a matched to the size of the lamp lens. Preferably, the luminaire insert allows a separate exchange of the LED chip and the heat sink and a complete reuse of the lamp housing.

• – einen Kühlkörper;
• – einen am Kühlkörper angeordneten LED-Chip;
• – eine Frontscheibe, welche zur Fixierung des Leuchteneinsatzes in einer Leuchte ausgelegt ist; und
• – eine Vielzahl von Führungsschienen mittels derer der Kühlkörper direkt oder indirekt an der Frontscheibe befestigt ist.

In one aspect, the invention in summary provides a luminaire insert, which comprises:

• A heat sink;
• - An arranged on the heat sink LED chip;
• - A windscreen, which is designed for fixing the lamp insert in a lamp; and
• - A variety of guide rails by means of which the heat sink is attached directly or indirectly to the windshield.

Preferably, the front screen has a transmission opening (light passage opening), in which a lens is arranged.

Preferably, the guide rails are fastened to a rear surface of the windshield facing the heat sink and the LED chip such that this attachment is not visible on a front surface of the windshield opposite the rear surface.

Preferably, the distance of the heat sink from the front window by sliding displacement of the heat sink to the guide rails is adjustable. Preferably, the guide rails are at least partially disposed in spaces between cooling fins of the heat sink.

Preferably, the guide rails are connected to one another via a bridge element arranged opposite the heat sink of the front pane. Particularly preferably, an adjusting element, in particular in the form of a knurled screw, connects the heat sink to the bridge element in an adjustable manner.

The invention will now be described by way of example with reference to exemplary embodiments with reference to the accompanying drawings. In particular, individual features of the above and / or below described aspects and / or embodiments can be combined detached from the respective aspect or the respective embodiment to form further embodiments. Showing:

1A and 1B FIG. 2: a schematic representation of a luminaire insert according to a preferred embodiment of the invention in a lateral view (FIG. 1A ) or a rear view ( 1B );

2A to 2C FIG. 2: a schematic representation of a luminaire insert according to a further preferred embodiment of the invention in a perspective view (FIG. 2A ), a side view ( 2 B ) or a rear view ( 2C );

3A and 3B FIG. 2: a schematic representation of a luminaire insert according to a further preferred embodiment of the invention in a lateral view (FIG. 3A ) or a rear view ( 3B ); and

4A and 4B FIG. 2: a schematic representation of a luminaire insert according to a further preferred embodiment of the invention in a lateral view (FIG. 4A ) or a rear view ( 4B ).

1A and 1B illustrate schematically an example of a luminaire insert according to a preferred embodiment of the invention. The luminaire insert comprises a windshield 1 which in particular has a circular outer edge. The diameter of this outer edge of the windscreen 1 is adapted to the desired field of application. For the use of the luminaire insert in luminaires with QR-70 or QR-111 sockets, the outside diameter of the preferably annular front screen could 1 about 70 mm or about 111 mm. But there are other diameters and even other forms of windshield for such lights 1 possible, which will be seen later in the further examples. So could the windscreen 1 for example, also oval or angular. By adjusting the size and shape of the windscreen 1 the luminaire insert is preferably adaptable to all common lights, especially lights with QR-70 and / or QR-111 sockets.

In particular, the windscreen serves 1 for fixing or mounting the luminaire insert in corresponding luminaires. For example, the windscreen acts 1 in particular at its outer edge with fastening elements of the luminaire, such as a spring "snap" mechanism, together to achieve a fixation of the luminaire insert in the luminaire or relative to the luminaire. In this case, such as. B. in the in 1A and 1B illustrated preferred embodiment, must be on the windscreen 1 no further special structural elements for attachment of the luminaire insert may be provided in a luminaire. Springs provided in the luminaire housing can be located directly on the outer edge of the windshield 1 attach and fix this. As will be described in further preferred embodiments, the windscreen can 1 have for fixing or mounting of the lamp insert in corresponding lights one or more fasteners over which a fastening, for example, by screws. In any case, by fixing the windscreen 1 preferably the entire luminaire insert sufficiently fixed in the lamp. This includes the windscreen 1 preferably sufficiently stable material, such. As metal, especially aluminum.

In the in 1A illustrated preferred embodiment is the windscreen 1 a flat disc. In particular, the windscreen is substantially in a plane perpendicular to a radiation axis 10 of the luminaire insert. In the illustration of the accompanying drawings, this emission axis is shown as a broken line with an arrow. In this case, the arrow shows in particular in a main emission of the luminaire insert, the direction of the arrow also determines what is understood in the context of the present description in the luminaire insert as "front". A viewing from a direction pointed by the arrow is thus considered to be "from the beginning". In this sense, to understand the terms front or back of the lamp insert or individual elements thereof.

As an alternative to the planar embodiment in the schematically illustrated embodiments, the windscreen could 1 also be at least partially curved and / or kinked or angled in this or other embodiments. In any case, the windscreen indicates 1 preferably a front surface 1a on, which at least partially forms a visible surface of the lamp insert. These are on the front surface 1a preferably no fasteners visible. Rather, the front surface 1a be decorative (polished, brushed, painted, printed, smooth, textured, etc.).

One of the front surface 1a opposite, so remote side of the windscreen 1 forms a back surface 1b the windscreen 1 , On the back surface 1b For example, fasteners can be used to fix the windscreen 1 and thus the luminaire insert may be provided in a luminaire. At least are on the back surface 1b later described in more detail guide rails 7 arranged and fixed, over which further components of the lamp insert relative to the windscreen 1 are attached.

In addition, the otherwise preferably opaque front window 1 in particular in a central region on a light passage opening, through which light from a later described in more detail LED chip 6 behind the windscreen can be radiated forward. The windscreen 1 is thus preferably annular. In the in 1A and 1B shown preferred embodiment is in the light passage opening of the windscreen 1 a lens 2 arranged and in particular attached to the windscreen. Preferably, the lens has an optical axis which coincides with the emission axis of the lamp insert. Depending on the focal length and distance of the lens 2 To a light source formed by the LED chip, the radiated light is guided to the front in a desired beam angle.

In addition, the luminaire insert includes the LED chip 6 that is attached to a heat sink 4 the lamp insert is arranged and attached thereto. Preferably, the LED chip 6 attached by means of screws to the heat sink and a thermally conductive good thermal conductivity of the heat sink 4 coupled. This can be used LED chip 6 and heat sink 4 z. B. for a repair of the light insert easily separate from each other and replace individually. It is also through the heat sink 4 a good derivative of the operation of the LED chip 6 resulting heat possible, whereby overheating of the LED chip can be avoided. This increases the life of the LED chip 6 ,

Preferably, the LED chip 6 essentially on the emission axis 10 the luminaire insert and / or the optical axis of the lens 2 arranged and designed, light with an opening angle of, for example, about 120 ° about the emission axis 10 centered to radiate forward. This is the LED chip 6 preferably on a mounting surface 12 of the heat sink 4 arranged substantially perpendicular to the emission direction 10 lies. That from the LED chip 6 radiated light is transmitted through the lens 2 Broken. Depending on the position of the LED chip 6 relative to the focal point of the lens 2 Thus, a desired illumination angle of the lamp insert is achieved.

According to the invention, the LED chip 6 and the heat sink 4 via a holder such on the Windscreen attached, that this attachment from the front is not visible. By this attachment is a certain, preferably changeable or adjustable position of the LED chip 6 relative to the windscreen 1 (especially to the lens 2 ), whereby the (preferably adjustable) illumination caused by the luminaire insert is determined. Preferably, the attachment to the back surface 1b the windscreen 1 , For this purpose, the luminaire insert, so the holder, by means of which the LED chip 6 and the heat sink 4 to the windscreen 1 are connected, in particular on the rear surface 1b the windscreen 1 fixed guide rails 7 at which the heat sink 4 preferably at least partially rests and is guided.

Preferably, the guide rails 7 by means of adhesive and / or soldering and / or welding connection on the back surface 1b the windscreen 1 fixed. Preferably, the guide rails 7 each have a longitudinal axis, which is substantially parallel to the emission axis 10 and / or optical axis. In a preferred embodiment, the guide rails comprise 7 one sleeve each with internal thread. This sleeve is bolted, for example, in a simple and efficient manner with a threaded pin (in particular a screw), which on the rear surface 1b the windscreen 1 is attached. This ensures a secure and yet detachable connection for repair purposes or for easy replacement of individual parts. Alternatively, the female threaded sleeves could at their front ends also directly on the windscreen 1 fixed (eg glued and / or soldered and / or welded).

As in 1A shown by way of example, includes the holder for the heat sink 4 preferably to each guide rail 7 a bridge bracket 8th which the respective guide rail 7 with a bridge element 3 , for example in the form of a connecting plate connects. Preferably, the bridge element connects 3 a variety of guide rails 7 , most preferably all guide rails 7 , on the back of the lamp insert, ie behind the heat sink 4 , together. As bridge brackets 8th For example, screws and / or rivets are provided. Most preferably, the bridge brackets include 8th in each case a threaded rod (in particular a screw), which in the internal thread of the guide rail 7 trained sleeve engages. Preferably, the threaded rod or the screw with an additional nut on the bridge element 3 attached. By combining an internally threaded sleeve with a threaded rod, the length of the luminaire insert (in the direction of the emission axis) can be adjusted flexibly and steplessly to the desired or required installation depth in a simple manner. In addition, an uncomplicated change of individual components of the luminaire insert is possible.

In the in 1A and 1B shown preferred embodiment are exactly two guide rails 7 intended. In this and other embodiments, additional guide rails could additionally be provided. These are preferably symmetrical (in particular at the same distance) about the emission axis 10 or optical axis arranged. Thus, the support forces are distributed evenly. The guide rails 7 are decentralized or peripheral, ie at least off the emission axis 10 or the optical axis, respectively. This is a high stability of the luminaire insert and in particular stable support or leadership of the heat sink 4 and with it the LED chip 6 relative to the windscreen 1 achieved, which in turn serves for fixing or mounting the lamp insert in the desired light.

In order to change the illumination angle of the luminaire insert easily and accurately and to be able to adapt to the desired application situation, is the heat sink 4 together with the LED chip 6 preferably continuously relative to the windscreen 1 (especially to the lens 2 ) displaceable or adjustable. This results in that the angle at which the light is emitted from the luminaire insert to the front, with respect to the opening angle of the emitted light cone is infinitely adjustable. Thus, all types of lights can be equipped with it, no matter whether it is a spotlight (which is targeted to illuminate a comparatively small area and thus makes a small, concentrated light flux necessary - small, narrow angle of light) or a floodlight (mainly a possible uniform illumination of a larger area should be achieved - large, wide angle of light) is. Preferably, the heatsink leaves 4 so adjust that the LED chip 6 any distance in a range of about the focal point of the lens 2 until about the lens 2 can take. But it can also be given a larger or smaller adjustment range. In this case, a greater distance, however, would essentially only lead to an increase in the required installation depth of the luminaire insert, without achieving a substantial increase in the flexibility with respect to the setting of a desired illumination. It is therefore particularly preferred to choose the mounting depth so that the largest possible distance of the LED chip 6 from the lens 2 the LED chip 6 in the area of the focal point of the lens 2 or even a little closer to the lens 2 lies.

This is the heat sink 4 in particular for an adjustment or displacement along an adjustment direction 10 parallel to the emission axis 10 or optical axis by means of the guide rails 7 guided smoothly. The guide rails 7 Therefore, they preferably serve not only as elements of the holder of the heat sink 4 but also prevent unwanted lateral movement (eg, rotation and / or tilting) of the heat sink while providing (sliding) movement of the heat sink along the displacement direction (radiation axis 10 , also called axial direction of the luminaire insert) allow. Preferably, the guide rails 7 closer to a peripheral edge 14 of the heat sink 4 as in its center (radiating axis 10 ) arranged.

The axial movement or position of the heat sink 4 is preferably by an adjustment 5 set or changed. The adjustment element 5 fixes the axial position of the heat sink 4 and allows on actuation of the adjustment 5 a preferably stepless change in the axial position of the heat sink 4 , Particularly preferred is the adjustment 5 centrally, ie in the area of the optical axis or emission axis 10 provided the luminaire insert. This can be done easily with a single adjustment 5 a comfortable, fast and safe adjustment or fixation of the axial position of the heat sink 4 can be achieved, wherein the adjustment and fixing forces act evenly or symmetrically and a canting, twisting or tilting of the heat sink 4 is avoided.

Preferably, the adjusting element comprises 5 a in the adjustment of the heat sink extending thumbscrew, which against movement in the axial direction (ie in the adjustment of the heat sink 4 ) with the bridge element 3 is connected, while a rotation of the thumbscrew about the screw axis is possible. The thread of the thumbscrew preferably engages in a provided in the heat sink internal thread. Thus, the axial position of the heat sink can be adjusted very precisely infinitely.

The holder of the heat sink 4 by means of peripherally arranged guide rails 7 , which in turn are not visibly fixed to the windshield from the front, ensures a stable and compact design, which can be used very flexibly for many lights. This design also ensures a good dissipation of heat generated during operation of the lamp insert heat. In particular, the construction allows good ventilation of the heat sink 4 to be able to dissipate heat from the heat sink.

2A to 4B show by way of example further preferred embodiments of the invention. In this case, analog components are marked with the same reference numerals. In this regard, therefore, the comments on 1A and 1B The same applies analogously to the exemplary embodiments of 2A to 4B be valid. In the following, only a few differences in the details of the construction will be discussed.

Thus, in the embodiments of 2A to 4B also cooling ribs 16 and spaces 18 between the cooling fins 16 shown schematically. These are preferably also in the embodiment of 1A and 1B provided, even if they are not shown in the schematic diagram. On the other hand, the LED chip 6 in an analogous manner in the embodiments of 2A to 4B even if it is not shown in all illustrations.

Notwithstanding the preceding example is in 2A to 2C an embodiment with a square front panel 1 described. In addition, four guide rails are exemplified in this embodiment 7 shown, which with a bridge element 3 by means of appropriate bridge brackets 8th are connected. In this case, the number of guide rails 7 regardless of the shape of the windscreen 1 to get voted. Especially in the perspective view of 2A It is good to see that the guide rails are preferably in the spaces between them 18 between the cooling fins 16 of the heat sink 4 run. This ensures a good guidance of the heat sink during the displacement, without the additional feedthroughs for the guide rails in the heat sink must be formed.

As in 2C is also in the embodiment of 3B one in the heat sink 4 Trained cable entry 20 shown. This allows the LED chip 4 be supplied on the front of the heat sink with the required electrical power from the back of the lamp insert ago. It is through the cable gland 20 preferably also achieved a strain relief for the cable.

In the in 4A and 4B illustrated embodiment are on the rear surface 1b the windscreen 1 in addition to the guide rails 7 also fasteners 22 arranged, which a mounting and fixing the windscreen 1 and thus enable the entire luminaire insert in the corresponding luminaire. Preferably, the fasteners 22 not visible from the front. They can be designed in particular as plug-in, clamping or screw elements. Although no such fasteners are shown in the preceding examples, they may also be provided there.

LIST OF REFERENCE NUMBERS

1

windscreen

1a

Front surface of the windscreen

1b

Rear surface of the windscreen

2

lens

3

bridge element

4

heatsink

5

Adjustment element (screw)

6

LED chip

7

guide rails

8th

bridge support

10

optical axis, emission axis, adjustment direction

12

mounting surface

14

peripheral edge of the heat sink

16

cooling fins

18

interspaces

20

Grommet

22

fasteners

Claims (7)

Luminaire insert comprising: - a heat sink ( 4 ); - one on the heat sink ( 4 ) arranged LED chip ( 6 ); - a windscreen ( 1 ), which is designed for fixing the lamp insert in a lamp; and a plurality of guide rails ( 7 ) by means of which the heat sink ( 4 ) on the windscreen ( 1 ) is attached. Luminaire insert according to claim 1, wherein the front window has a transmission opening, in which a lens ( 2 ) is arranged. Luminaire insert according to one of the preceding claims, wherein the guide rails ( 7 ) on a heat sink ( 4 ) and the LED chip ( 6 ) facing back surface ( 1b ) of the windscreen ( 1 ) and that this attachment to one of the rear surface ( 1a ) opposite front surface ( 1a ) of the windscreen ( 1 ) is not visible. Luminaire insert according to one of the preceding claims, wherein the distance of the heat sink ( 4 ) from the windscreen ( 1 ) by sliding the heat sink ( 4 ) on the guide rails ( 7 ) is adjustable. Luminaire insert according to one of the preceding claims, wherein the guide rails ( 7 ) at least partially in intervals ( 18 ) between cooling fins ( 16 ) of the heat sink ( 4 ). Luminaire insert according to one of the preceding claims, wherein the guide rails ( 7 ) via a with respect to the heat sink ( 4 ) of the windscreen ( 1 ) oppositely arranged bridge element ( 3 ) are interconnected. Luminaire insert according to claim 6, wherein a setting element ( 5 ), in particular in the form of a knurled screw, the heat sink ( 4 ) with the bridge element ( 3 ), adjustable connects.

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