DE102011081369A1 - Lamp i.e. LED lamp, has lamp housing including intermediate region for reducing heat transfer between LED light source and operating device, where intermediate region separates housing parts by thermal insulation - Google Patents

Abstract

The lamp has a coherent lamp housing (20) including a housing part (12) provided with an LED light source, another housing part (22) provided with an operating device (24), and air ducts (32, 34) for convection cooling of the lamp. The lamp housing includes an intermediate region (40) for reducing the heat transfer between the LED light source and the operating device, where the intermediate region separates the housing parts by thermal insulation. The housing parts are provided with spacers (42) for the formation of the intermediate region.

Description

The invention generally relates to the cooling of luminaires and more particularly to a luminaire with passive cooling for light-emitting diodes or light-emitting diodes or other solid-state or solid-state light sources.

Despite higher efficiency and light output compared to conventional bulbs, it also comes in efficient solid state bulbs, such as light-emitting diodes or light-emitting diodes (hereinafter short LED), in operation to considerable heat. This is especially true for power lamps such as e.g. in so-called high-power LED for direct lighting. In addition, typically also Joule waste heat of the required control gear.

As is known, a low operating temperature is required in particular for the longest possible service life and energy-optimized operation of solid-state light sources. Accordingly, lights for such bulbs and especially the light housing should be designed so that despite considerable heat generation, the necessary low operating temperature for all components, in particular the light source is ensured.

It is known to use this active coolant such as fans, as in DE 10 2007 019074 or DE 10 2009 019226 proposed. However, this approach is costly and energetically inefficient, among other things because of the additional energy consumption for active cooling. Accordingly, preference is given to solutions with passive cooling, as for example in the utility model DE 20 2011 003 010 proposed. The DE 20 2011 003 010 discloses an LED light, more precisely a recessed ceiling light, with passive cooling. This luminaire has an integrally connected luminaire housing with an LED illuminant in the first lower part of the housing. An electronic operating device for the LED lamp is thermally connected to the housing in the upper housing part with potting compound. As a means for convection cooling of the lamp housing are provided circumferentially on the housing vertical cooling fins. These generate a chimney effect of an air flow and passively cool both the LED illuminant and the operating device, which are thermally coupled through the housing body. Despite the advantages of passive cooling according to DE 20 2011 003010 There is a further need for improvement, since active cooling with a fan is also required for this device at high powers (see 8th out DE 20 2011 003010 ). This solution is also not readily applicable in lights with a large number of LED segments, which are fed by a common operating device, or with several high-performance bulbs.

An object of the present invention is therefore to improve the passive cooling of a generic lamp. This object is achieved by a luminaire according to claim 1 or by a luminaire housing according to claim 10.

According to the invention, the luminaire has an intermediate region for reducing the heat transfer between the luminous means or the luminous means and the operating device. This intermediate region forms a spatial separation between a first and a second housing part of the luminaire housing and constitutes a thermal insulation. The luminous means and the operating device are consequently arranged in two mutually thermally separated spaces.

As a result of the thermal separation according to the invention, the associated components can each be cooled independently of one another. In particular, the cooling can be dimensioned specifically for high-performance illuminants and independently of the operating electronics used. In addition, short paths to the ambient air are made possible, in particular for the convection cooling of the lamps in the first housing part. Furthermore, it is possible to produce maintenance-free luminaire housings without moving parts, with a low susceptibility to soiling and possibly more attractive aesthetics.

In a preferred embodiment, the first and the second housing part are designed as a single, in each case self-contained closed housing and releasably or non-detachably connected to each other. This allows u. a. a modular design, for example, to use a plurality of first housing parts for lamps with a single operating device or a single second housing part. Alternatively, the luminaire housing can also be embodied with integrally connected first and second housing parts and intervening molded intermediate area.

In a particularly simple embodiment of the intermediate region between the first and second housing part is formed by means of one or more spacers, which ensure a gap. Such spacers can be provided on the first or on the second housing part or on both.

Preferably, the first housing part comprises a in the main plane of the lamp substantially rectangular shaped base body with a plurality thereof at least circumferentially and externally provided ventilation ducts. The latter are referred to below as external ventilation ducts. Such a base body made of a thermally conductive material may preferably be produced in one piece by die-casting, so that the first housing part is essentially produced as a robust die-cast housing. The outer ventilation ducts are preferably fully circumferentially, ie distributed over the entire circumference of the first housing part, provided and preferably formed with or in one-piece body.

In a preferred development, the luminaire housing has two first housing parts lying next to one another in the main plane. The second housing part is in this case preferably designed so that it is also designed substantially rectangular in the main plane of the lamp and has a plurality of centrally located within the second housing part ventilation ducts. These central ventilation channels may be provided in the longitudinal direction or in the width direction, depending on the orientation of the second housing part in comparison to the first housing parts. As a result, the second housing part can be connected to the two first housing parts in such a way that at least part of the outer ventilation channels of the two first housing parts cooperate with the central ventilation channels of the second housing part. In particular, a part of the ventilation channels of the first housing parts can thereby be aligned vertically or coaxially with the central ventilation channels of the second housing part. This avoids that Entwärmungswege cross and benefits the cooling of the first housing parts supporting the second housing part.

In an advantageous development of the first housing part, its base body has at least two separate receptacles which can each accommodate a corresponding solid-state illuminant. These separate receptacles are preferably separated from one another by a plurality of ventilation channels provided in the base body, which are lined up in the longitudinal or in the width direction of the base body. The latter ventilation ducts are referred to below as inner ventilation ducts. Through these additional inner ventilation ducts, the entire cooling capacity of the body is increased, whereby a reliable passive cooling, for example by convection, is ensured even with high-performance bulbs. By utilizing such inner ventilation ducts, it is preferably provided that the intermediate area is ventilated and the inner ventilation ducts open into this intermediate area. This is achieved in that the inner ventilation ducts have a shorter length than the overall height of the first housing part, measured from the front to the back of the main body. As a result, a simple air layer is used as insulation between the first and the second housing part, which can serve by appropriate ventilation connection to the outside at the same time the discharge of heated exhaust air from the inner ventilation ducts.

Preferably, the outer ventilation ducts of the first housing part and the central ventilation ducts of the second housing part each extend transversely to the main plane and have mutually identical cross sections in the main plane. Further, these ventilation ducts, in contrast to the inner ventilation ducts of the first component, preferably an extension over the entire height of the first and the second housing part.

For optimum cooling, at least a portion is preferably formed a majority of the boundary walls of the outer or inner ventilation ducts in the first housing part by ribs, which are integrally or integrally formed with the main body. Such ribs preferably run perpendicular to the narrow sides of the body, d. H. the sides that connect the front and back. The use of essentially vertical cooling channels (in the case of the main horizontal plane of the housing parts) also avoids the accumulation of dust particles or other dirt in the luminaire housing.

The invention also relates to a preferred embodiment of the first housing part per se, d. H. a housing part for a lamp with passive cooling as described above.

According to the invention, a preferred housing part as a separate component has a depression on its rear side for forming the above-described intermediate region, which reduces or completely eliminates heat transfer between solid-state illuminants and the operating device when the luminaire housing is assembled. This embodiment has the particular advantage of allowing a modular construction of luminaire housings with a plurality of such housing parts.

However, other embodiments, for example. With integrally molded luminaire housing and molded intermediate area are possible.

Further advantages and features of the invention will become apparent from the following description of a preferred embodiment with reference to FIGS. Show it:

1 a front view of a lamp according to the invention with passive cooling;

2 a longitudinal cross-section of the lamp according to section plane II-II 1 ;

3 a perspective view of the back of a lamp according to 1 - 2 ,

1 - 3 show a lamp, generally with 10 designated. 1 shows the light 10 in front view, from the illuminated side, the plane of 1 the main level of the luminaire 10 equivalent. The lamp 10 has two first housing parts lying side by side in the main plane 12 , In the example shown, each of the first two housing parts 12 three shots each 14 for receiving bulbs, in particular LED segments 16 , Every LED segment 16 is preferably designed as a printed circuit board and with a plurality of light-emitting diodes 17 (LEDs for short). In the example off 1 - 3 has every LED segment 16 purely by way of example several high-power LEDs 17 in semiconductor technology. A typical light 10 So it has more than 20 high-power LEDs 17 and thus a plurality of individual heat-emitting light sources. However, the invention also relates to other solid-state light sources such as OLEDs. Every first housing part 12 preferably comprises a one-piece molded body 18 in which the shots 14 as wells 44 are incorporated or molded. The main body 18 is made of a suitable thermally conductive material such as aluminum, preferably in die casting. The basic form of the basic body 18 is rectangular in the main plane corresponding to the plurality of square recesses 14 , like out 1 seen. Both housing parts 12 are joined together flush on their long sides.

The first two housing parts 12 are part of a 2 - 3 generally with 20 designated luminaire housing. The luminaire housing 20 also includes a second housing part 22 how best 2 - 3 seen. The second housing part 22 protects in an appropriate recording 23 a control gear 24 for electrical supply and possibly for controlling the LED 17 in the individual LED segments 16 , The operating device 24 Similar to an electronic ballast typically includes a conventional or electronic transformer with rectifier and possibly a suitable control circuit, each of known type. The second housing part 22 can be produced in any technique, in particular as inexpensively as possible, for example, welded metal sheet metal parts. The second housing part 22 may be suitable means for ceiling mounting, wall mounting or chain suspension of the lamp 10 each with suitable accessories (not shown). The second housing part 22 is, apart from about curves on the corners or the like, also in the main plane of the lamp 10 essentially rectangular, as in 3 shown. How out 2 - 3 further, the first housing parts form 12 together with the second housing part 22 joins together a coherent luminaire housing 20 , For this purpose, the housing parts 12 . 22 releasably or permanently connected to each other, for example by screw or gluing. Preferably, each housing part forms 12 . 22 By itself, however, a single closed housing with one or more shots 14 . 23 for corresponding components.

The first housing part 12 preferably comprises each receptacle 14 a translucent protective cover 19 , The protective cover 19 are in the main body 18 kept detachable or unsolvable. The protective cover 19 can be made transparent or frosted and together with suitable LED segments 16 achieve direct or indirect, symmetrical or asymmetrical lighting. The protective cover 19 can optically acting, for example. As a lens configured.

The cooling of the lamp 10 takes place according to the invention passively. This is in the luminaire housing 20 a variety of Kühlbzw. Ventilation channels provided, which transversely to the main level ( 1 ). The cooling or ventilation ducts are thus at horizontally arranged light ( 2 ) vertically aligned so that a chimney effect for convection cooling arises. Every first housing part 12 includes at least a plurality of uniform and preferably over the entire circumference provided outer ventilation ducts 32 , The outer ventilation ducts 32 are circumferential ie as a continuous boundary along both longitudinal and broad sides of the body 18 arranged. Continue to show 1 - 3 in the main body 18 inside additional ventilation ducts 34 , These inner ventilation ducts 34 are along a transverse line in the width direction of the first lamp housing 12 lined up and separate each two shots 14 from each other. With a different number of shots, there are internal ventilation channels in between 34 arranged according to a grid. The inner ventilation ducts 34 increase the cooling capacity of the first housing part 12 overall and ensure more even cooling of the individual LED segments 16 ,

In the second housing part 22 shows 3 Centered in the longitudinal direction further ventilation ducts 36 , How best 3 can be seen, are the central ventilation ducts 36 in the second housing part 22 so provided that they have an inner part of the adjacent outer ventilation ducts 32 of the first housing part 12 interact. Preferably, the ventilation ducts 36 vertically or coaxially aligned with the opposite portion of the outer ventilation ducts 34 of the first housing part 12 arranged. Although the first two housing parts 12 in front view (see 1 ) the second housing part 22 completely cover, by this aligned arrangement of ventilation ducts 34 and 36 in the housing parts 12 . 22 also a sufficient cooling of the operating device 24 ensured, without the cooling of the LED segments 16 to impair. The outer ventilation ducts 32 in the first housing part 12 as well as the central ventilation ducts 36 in the second housing part 22 also run with their longitudinal axis transverse to the main plane ( 2 ) and preferably over the entire height of the first and second housing part 12 . 22 , Continue to 2 have the inner ventilation ducts 34 in the first component, however, a shorter overall length and extend transversely to the main plane, so they just before the second housing part 22 end up.

How out 2 can be seen, both the outer and the inner ventilation ducts 32 . 34 directly into the integral body 18 formed. This form one-piece with the body 18 shaped cooling fins 38 transverse to the narrow sides of the body 18 or first housing part 12 a part of the boundary walls of the outer and inner ventilation ducts 32 . 34 , Together with a preferably also in one piece with the body 18 shaped border 39 and the opposite inner boundary of the outer ventilation ducts 32 or the recordings 14 form such cooling fins 38 thus an overall large cooling surface. The entire body 18 represents a single contiguous heat sink for all LED segments 16 represents.

According to the invention, the first housing parts 12 thermally and spatially separated from the second housing part 22 through a specially provided intermediate area 40 which is best 2 is apparent. The intermediate area 40 serves to reduce the heat transfer between the solid state illuminants 16 and the operating device 24 , The intermediate area 40 thus has the function of thermal insulation between the housing parts 12 . 22 , However, a special insulation material is not required and preferably not in the intermediate area 40 intended. The intermediate area 40 also serves as the "air layer" of the thermal insulation of the heat sink of the LED segments 16 , ie the basic body 18 from the operating device 24 , which also gives off a considerable amount of heat.

In the embodiment shown is in the main body 18 provided on the back of a corresponding recess, in which spacer 42 protrude to the second housing part 22 forming the intermediate area 40 at a distance from the LED segments 16 in the one or more housing parts 12 to keep. The spacers 42 can be hollow and at the same time as wiring for connecting lines between the LED segments 16 and the operating device 24 serve. In addition or alternatively, the spacers 42 for fixing the second housing part 22 at the base body 18 be used. How farther 2 visible, open the inner ventilation ducts 34 in the intermediate area 40 , Accordingly, the intermediate area 40 preferably deaerated, ie the intermediate area 40 is in open communication with the ambient air. This can for example be achieved in that the back of the first housing parts 12 not completely from the second housing part 22 is covered, as in 3 shown. Complementary or alternative to spacers 42 at the base body 18 can also spacers on the second housing part 22 be provided. Accordingly, instead of a depression 44 in the main body 18 also a corresponding depression additionally or exclusively on the front side of the second housing part 22 be provided to the intermediate area 40 to build. Alternatively, an insulating intermediate region may also be used 40 be incorporated directly into an integrally manufactured luminaire housing (not shown), for example in the form of a cavity.

By the described embodiment of the first housing part 12 can each be the main body 18 as a heat-conducting heat sink especially for the LED segments 16 be used. The entire body 18 is used for heat conduction to the ventilation or cooling channels 32 . 34 exploited. The in the main body 18 integrated cooling channels 32 . 34 form sufficient and purely passive means for convection cooling of all LEDs 17 in the first housing part 12 , Thus, by heat convection, the waste heat can be dissipated, which inevitably arises despite efficient lighting. In the example shown so is waste heat of a variety of high-power LEDs 17 dissipated so that the LEDs 17 be operated at the lowest possible temperature.

Also the second housing part 22 is advantageous purely passive by convection cooled by its central ventilation ducts 36 , The from the operating device 24 generated heat, however, is separated and only by the second housing part 22 or its cooling channels 36 dissipated. The intermediate area 40 avoids additional heating of the thermally separated first housing part 12 through the operating device. A damage caused by overheating of the operating device 24 In addition, the LED segments 16 no longer damage or interfere.

As a significant advantage allows a thermal separation according to the invention through the intermediate region 40 an energy-efficient and at the same time cost-effective design of the cooling especially for the light sources. In the example shown are also the heat sources 16 . 24 arranged so that airways do not intersect for cooling, the shortest possible routes are guaranteed to the ambient air and also the proportion of aligned outer ventilation ducts 32 as a "flow motor" for the central ventilation ducts 36 in the second housing part 22 acts.

LIST OF REFERENCE NUMBERS

10

 lamp

12

 first housing part

14

 admission

16

 LED segment

17

 LED

18

 body

19

 protective cover

20

 luminaire housing

22

 second housing part

23

 admission

24

 control gear

32

 external ventilation ducts

34

 inner ventilation ducts

36

 central ventilation ducts

38

cooling fins

39

 border

40

 intermediate area

42

 spacer

44

 deepening

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 102007019074 [0004]
• DE 102009019226 [0004]
• DE 202011003010 U [0004]
• DE 202011003010 [0004, 0004, 0004]

Claims (10)

Lamp ( 10 ), in particular LED luminaire, with passive cooling comprising a coherent luminaire housing ( 20 ) with at least one first housing part ( 12 ) and with a second housing part ( 22 ), at least one solid state illuminant ( 16 ), in particular an LED illuminant, in the first housing part ( 12 ), a control gear ( 24 ) in the second housing part ( 22 ), and means ( 32 ; 34 ) for passive cooling, in particular for convection cooling, of the luminaire housing ( 20 ); characterized by an intermediate region ( 40 ) in the luminaire housing for reducing the heat transfer between solid-state lamps ( 16 ) and operating device ( 24 ), the intermediate area ( 40 ) the first housing part ( 12 ) from the second housing part ( 22 ) spatially separates and represents a thermal insulation. Luminaire according to claim 1, characterized in that the first housing part ( 12 ) and the second housing part ( 22 ) represent individual closed housing, which are interconnected. Luminaire according to claim 1 or 2, characterized in that on the first housing part ( 12 ) and / or on the second housing part ( 22 ) at least one, preferably a plurality of spacers ( 42 ) are provided for forming the intermediate region ( 40 ). Luminaire according to one of the preceding claims, characterized in that the first housing part ( 12 ) one in the main plane of the luminaire ( 10 ) substantially rectangular basic body ( 18 ) and a plurality of circumferentially along the sides of the first housing part ( 12 ) provided outer ventilation ducts ( 32 ). Luminaire according to claim 4, characterized in that the second housing part ( 22 ) in the main plane of the luminaire ( 10 ) is substantially rectangular and a plurality of centers within the second housing part ( 22 ) in the longitudinal or the width direction side by side arranged ventilation ducts ( 36 ), that the luminaire housing ( 20 ) two in the main plane adjacent to each other first housing parts ( 12 ), and that the second housing part ( 22 ) so with the first housing parts ( 12 ), that at least a part of the outer ventilation ducts ( 32 ) of the first housing parts ( 12 ) with the central ventilation channels ( 36 ) of the second housing part ( 22 ), in particular aligned with each other to form coaxial ventilation ducts ( 32 ; 36 ). Luminaire according to claim 4 or 5, characterized in that the basic body ( 18 ) of the first housing part at least two separate recordings ( 14 ) each for a solid-state light source ( 16 ), which by internal ventilation ducts ( 34 ), which are arranged side by side in the longitudinal or width direction, and preferably have the same cross-section in the main plane as the central ventilation channels of the second housing part (FIG. 22 ). Luminaire according to claim 6, characterized in that the intermediate region ( 40 ) is ventilated and the inner ventilation ducts ( 34 ) have a shorter length than the overall height of the first housing part ( 12 ), so that the inner ventilation ducts ( 34 ) in the intermediate area ( 40 ). Luminaire according to one of claims 4 to 7, characterized in that the outer ventilation ducts ( 32 ) of the first housing part ( 12 ) and the central ventilation ducts ( 36 ) of the second housing part ( 22 ) extend transversely to the main plane and the height of the first and second housing part. Luminaire according to one of claims 4 to 8, characterized in that in one piece with the main body ( 18 ) molded cooling fins ( 38 ) at least part of the boundary walls of the outer ventilation ducts ( 32 ) or the inner ventilation ducts ( 34 ) form. Housing part ( 12 ) for a luminaire, in particular an LED luminaire, with passive cooling comprising a main body ( 18 ) with a front and a back; at least one recording ( 14 ) for a solid-state light-emitting means, in particular an LED light-emitting means, in the front side of the main body; Means at the back of the body for releasably connecting the housing part with a further housing part, in which an operating device is provided, to a continuous lamp housing; and means for convection cooling, in particular cooling fins formed integrally with the main body ( 38 ); characterized by a depression ( 44 ) at the back of the body ( 18 ) to form an intermediate region ( 40 ) with the luminaire housing joined together, the intermediate area ( 40 ) the housing part ( 12 ) spatially separates from the other housing part and a thermal insulation is to reduce the heat transfer between solid-state lighting and control gear.

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