EP2561725B1 - Led module with passive led - Google Patents

Description

The invention relates to an LED module consisting of a plurality arranged on a printed circuit board LED, each having a so-called embedding with a lens with which the respective LED protrudes from the PCB level, the LED are each coupled to a Lichteinkopplungselement a Lichtleitköpers and through the respectively associated Lichteinkopplungselement the respective luminous flux of the associated LED from the LED is emitted to the outside.

LED modules consisting of several arranged on a PCB LED have been known for some time. Such an LED consists of an anode terminal, a cathode terminal, and a "cup" in which an LED crystal is inserted. This LED crystal is connected to the anode connection via a bonding wire. To protect both the cathode terminal and the anode terminal and the LED crystal these components are embedded in a so-called "embedding", which is usually made of a plastic. As a rule, this embedding forms a kind of lens so that the light beam emitted by the LED crystal is radiated over as large a surface area as possible in order to minimize the glare effect of the observer.

Since such LEDs have a meantime sufficient for lighting purposes light intensity, it is increasingly passed on to lately, such LED also for lighting a variety of Type in. In particular, it is known to arrange such LEDs in a matrix-like multiple arrangement on a printed circuit board in order to achieve a sufficient luminosity.

Although the lifetime of such LED is given with several thousand hours, but it is still observed that individual LEDs of a LED module can fail prematurely. If several LEDs are provided, the failure of one LED with respect to the total light output of the entire LED module is generally negligible. However, the failure of an LED when viewing the LED module is visible to the outside and disturbs the one hand, the appearance of the LED module. Although the luminous intensity of the LED module is still sufficient if one LED fails, the LED module is often replaced due to this disturbing appearance, so that unnecessary costs are incurred here.

From the US 2002/0089418 A1 an LED module is known, which consists of several arranged on a circuit board LED, each having a so-called embedding with a lens with which the respective LED protrudes from the circuit board level. The LEDs are each coupled to a Lichteinkopplungselement a Lichtleitköpers. By the respectively associated Lichteinkopplungselement the respective luminous flux of the associated LED is emitted from the LED module to the outside. An overlap of the light cone prevents the direct appearance of a failure of individual LEDs. However, this leads to a greater decrease in the total light output.

Accordingly, the invention has for its object to provide an LED module consisting of several arranged on a printed circuit board LED available, in which the failure of individual LED does not appear to the outside in appearance.

The object is achieved according to the invention together with the features of the preamble of claim 1, characterized in that on the circuit board to the LED at least one passive LED is provided which can be activated in case of failure of the LED and that emitted by the passive LED luminous flux irradiated in the Lichteinkopplungselement the failed LED and is emitted via the Lichteinkopplungselement to the outside.

As a result of this embodiment, the "incoupling" of the luminous flux emitted by the passive LED into the light coupling element of the failed LED continues to make it luminous, so that the overall optical impression of the LED module is not disturbed.

Furthermore, it can be provided according to claim 2 that a plurality of passive LEDs are provided which are assigned to a plurality of LEDs with their light coupling elements and that the respective passive LED can be activated in the event of failure of one of the respective associated LEDs. By this configuration, the number of passive LED to be used can be reduced to a minimum. The respective passive LEDs are preferably arranged between the LED arranged in a matrix, so that the luminous flux of the passive LED can simultaneously reach several Lichteinkopplungselemente the surrounding LED and thus several Lichteinkopplungselemente are supplied simultaneously by a single passive LED with the required luminous flux can.

Fig. 1

eine perspektivische Draufsicht einer Leiterplatte mit aufgesetzten LED und mehreren zwischen den LED angeordneten Passiv-LED;

Fig. 2

eine Schnittdarstellung II-II aus Fig. 1 eines vollständig montierten als Lichtquelle dienenden LED-Moduls.

Reference to the drawings, an embodiment of an LED module equipped with the passive LED according to the invention is explained in more detail below by way of example. It shows:

Fig. 1

a top perspective view of a printed circuit board with attached LED and a plurality of arranged between the LED passive LED;

Fig. 2

a sectional view II-II Fig. 1 a fully mounted as a light source LED module.

Fig. 1 shows by way of example a possible embodiment variant of a printed circuit board 75 which is equipped with a plurality of arranged in a matrix LED 76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89. Each of these LEDs 76 to 89 are each provided with an outwardly projecting lens 100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112 and 113, respectively, which are incorporated in a LED. Module 1 inserted state each protrudes into a Lichteinkopplungselement 30, 31, 32, 33 of a light guide body 2, as for the LED 76, 77, 78 and 79 from Fig. 2 is apparent.

In the present embodiment, a total of three passive LEDs 95, 96 and 97 are provided. In the present case, the passive LED 95 is assigned to the LEDs 78, 79, 80, 81, 89 in a light-optical manner, so that a luminous flux emitted by the passive LED can reach these adjacent LEDs 78, 79, 80, 81, 89. The passive LED 96 is similarly associated with the LED 76, 77, 83, 87, 88, while the passive LED 97 is associated with the LED 82, 84, 85, 86.

Furthermore, it is off Fig. 1 It can be seen that the printed circuit board 75 is provided in the region of the LED 76 and 88 with a schematically illustrated electrical connector 115, via which all LED 76 to 89 together or in groups, the required operating energy can be supplied.

Regarding the operation of this passive LED 95, 96 and 97 shows Fig. 2 a simplified sectional view II - II off Fig. 1 a mounted LED module 1. Due to the cut are in Fig. 2 Accordingly, only the arranged on the circuit board 75 LED 76, 77, 78 and 79 with their lenses 100, 101, 102, and 104 and the "between" these arranged passive LED 95 and 96 can be seen.

When mounted, the LEDs 76, 77, 78, 79 project with their respective spherically curved lenses 100, 101, 102, 103 into the respectively assigned light coupling element 30, 31, 32, 33, so that the light coupling elements 30, 31, 32, 33 incoming luminous flux, for example, substantially parallel through the Lichteinkopplungselemente 30, 31, 32, 33 in the direction of the arrow 116 is emitted to the outside. On the Lichteinkopplungselemente 30, 31, 32, 33, further optical systems can be placed or upstream of a predetermined distribution of the luminous flux.

How out Fig. 2 it can be seen, the printed circuit board 75 is received in the LED module 1 between a light guide 2 and a housing plate 66. In the present case, the light-guiding body 2 is fixedly mounted on the underside of the housing plate 66 via a mounting frame 20 and can be screwed to it, for example detachably. In the region of the mounting flange 25 of the mounting frame 20, a seal 65 is inserted and thus the mounting frame 20 sealed completely circumferentially about this seal 65 relative to the housing plate 66. Also, the mounting frame 20 and the light guide 2 may be integrally formed.

Furthermore, it can be seen that the LEDs 76, 77, 78 and 79 with their lenses 100, 101, 102, 103 protrude into the respective associated light coupling element 30, 31, 32, and 33, respectively. By means of these light coupling elements 30, 31, 32, 33, the light rays emitted conically by the LEDs 76 to 79 or their lenses 100 to 103 are thus emitted in the direction of the arrow 116 essentially to a uniform luminous flux vertically downwards.

If one of the LEDs 76, 77, 78 or 79 now fails, one of the passive LEDs 95 and 96 associated with the LEDs 76, 77 and 78, 79 can be activated by a corresponding control. Depending on which of the LED 76, 77, 78 or 79 has failed, accordingly, a luminous flux in the direction of the arrow 3 or 4 in the Lichteinkopplungselemente 30, 31 and 32, 33 is irradiated and of these, for example, in the direction of the respective arrow 116 redirected to the outside.

The corresponding LED or the corresponding Lichteinkopplungselement 31, 31 and 32, 33 thus appears outwardly still lit, so that the external appearance of the LED module 1 is not disturbed.

It is therefore outwardly not - or only for the trained eye of an observer - recognizable that one of the LED 76, 77, 78 or 79 has failed. An advantage of this embodiment is further that the passive LED 95, 96 and 97 can be operated with much lower power than the high-power LED 76 to 89 from Fig. 1 , This makes it possible to simulate the functionality of a failed LED with extremely low energy consumption.

Claims (2)

1. LED module (1) comprising a plurality of LEDs (76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89) which are arranged on a printed circuit board (75) and which each have a "bedding element" with a lens (100, 101, 102, 103, 104, 105, 106, 107, 108, 109, 110, 111, 112, 113) with which the respective LED (76, 77, 78, 79, 80, 81, 82, 83, 84, 85, 86, 87, 88, 89) protrudes from the printed circuit board plane, wherein the LEDs (76 to 89) are each coupled to a light input element (30, 31, 32, 33) of an optical waveguide body (2) and the respective associated light input element (30, 31, 32, 33) radiates the respective luminous flux from the associated LED (76 to 89) outwards from the LED module (1),
   characterized
   in that the printed circuit board (75) for the LEDs (76 to 89) has at least one passive LED (95, 96, 97) provided on it which can be activated if one of the LEDs (76 to 89) fails, and
   in that the luminous flux (arrows 3 and 4) emitted by the passive LED (95, 96, 97) shines into the light input element (30, 31, 32, 33) of the failed LED (76 to 89) and is radiated outwards via the light input element (30, 31, 32, 33).
2. LED module according to Claim 1, characterized in that a plurality of passive LEDs (95, 96 and 97) are provided which are associated with a plurality of LEDs (78, 79, 80, 81, 89 and 76, 77, 83, 87, 88 and 82, 84, 85, 86) with the light input elements (30, 31, 32, 33) thereof and
   in that the respective passive LED (95, 96 or 97) can be activated if one of the respective associated LEDs (78, 79, 80, 81, 89 and 76, 77, 83, 87, 88 and 82, 84, 85, 86) fails.

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