WO2010009781A1

WO2010009781A1 - Emergency light unit

Info

Publication number: WO2010009781A1
Application number: PCT/EP2009/003405
Authority: WO
Inventors: Markus Markstaler
Original assignee: Tridonicatco Gmbh & Co. Kg
Priority date: 2008-07-24
Filing date: 2009-05-13
Publication date: 2010-01-28
Also published as: DE102008034524B4; CN102105680A; CN102105680B; EP2310668A1; DE102008034524A1

Abstract

The invention relates to an emergency light unit (3) for connecting to an operating device (2) fed by a supply source (1) and comprising at least one illumination LED (4). To this end, a status LED (7) signalizing normal or faulty operation of the illumination LED (4) can be additionally provided. In order to be able to detect by typical self-tests a reduction in the light intensity of the illumination LED (4) due to aging, for example, the emergency light unit (3) comprises at least one first photosensor (6) and a control circuit part (5). The photosensor (6) reports to the control circuit part (5) when a minimum illumination strength of the illumination LED (4) is no longer met, with the result that the control circuit part (5) generates an error state that can be detected by a self-test program.

Description

emergency pack

The invention relates to an emergency lighting unit, which is to be connected to a powered by a supply source operating device and comprises at least one illumination LED.

For emergency lighting in general and LED emergency lighting in particular, self-testing is required at regular intervals. In particular, it records whether a current, an interruption error or a short-circuit fault has occurred during a self-test. When a permissible current is flowing, it is concluded with LED emergency lighting that the LED (hereafter referred to as "LED" for simplicity only, even if the light source is made up of multiple LEDs) functions properly However, self-test can not detect when the luminosity of the LED deteriorates, for example due to aging.

The invention has for its object to avoid the last-mentioned disadvantage.

The invention is achieved by an emergency lighting unit having at least one illumination LED, which is characterized by the features of claim 1.

Thereafter, the illumination LED is associated with a photosensor whose output signal is evaluated by a control circuit to determine whether the emitted by the illumination LED light falls below a certain minimum illuminance or a certain minimum luminous flux. The result of this test can then be used to adjust the emergency lighting unit to assume a fault condition detectable by the self-test program.

It is known to additionally provide an emergency lighting unit of the type described above with at least one status LED which indicates the correct or faulty function of the lighting LED.

The invention is further based on the object of detecting malfunctions of the status LED and / or adapting the brightness of the status LED to the brightness of the ambient light or the illumination LED.

The further object is achieved by an emergency light unit with the features of claim 2. This solution also provides for the use of a photosensor, which in this case serves in conjunction with a control circuit for function control and / or brightness control of the status LED.

According to claim 3, it is also possible, in addition to a first photosensor additionally provide a further photosensor, in which case the further photosensor for function control and / or brightness control of the status LED is used.

Claim 4 relates to a development of the case that the status LED and the illumination LED are monitored by a single photo sensor. In this case, the light of each of the two LEDs can be time multiplexed on the Photosensor are irradiated, in which case the evaluation of the output signal of the photosensor by the control circuit must be carried out in the same time division multiplex.

As already mentioned, it is known in the prior art that the operating device contains a self-test program, which checks the supplied and controlled by him lighting LED at regular intervals for a short circuit or interruption defect. In accordance therewith, it is proposed according to claim 5 for further development of the emergency lighting unit according to claim 1, that the control circuit part then artificially generates a short circuit or interruption defect in the circuit containing the lighting LED, if the first photosensor falls below the minimum luminous flux or the minimum Illuminance determines so that the operating device recognizes the last-mentioned underrun trap as fault conditions.

A disadvantage of the known emergency lighting systems may be that the human eye can no longer distinguish the less brightly illuminated status LED from the much brighter illuminating LED at a certain distance. According to claim 6 is therefore proposed that the illumination LED and the status LED are spatially separated from each other so that a secure perception over a predetermined distance is still possible. Alternatively or additionally, the illumination LED and the status LED according to claim 7 can be separated from each other by a partition wall, preferably a reflector wall, so that the status LED is shaded by the illumination LED. Another measure for avoiding the last-mentioned disadvantage may consist in that the brightness of the status LED is adapted to the brightness of the illumination LED according to claim 8. If the illumination LED shines with high brightness, the status LED should also emit light with increased brightness.

Claim 9 relates to the possibility of monitoring the status of the status LED and suggests that a brightness defect of the status LED detected by the further photosensor causes the control circuit part to control the illumination LED in such a way that it generates an optical signal, for example in FIG Form of blinking, giving off.

According to claim 10, an actively operating photodiode or a passive photoresistor can be used as the photosensor, wherein the supply voltage for the passive photoresistor, an external voltage, such as the supply voltage for the illumination LED or the supply voltage for the status LED offers.

Another proposal for further development of the emergency light unit according to the invention is according to claim

11 in that the first and / or the second photosensor in addition to the configuration, programming or

Addressing the emergency light unit hernagezogen, which can be done by a separate light source, for example by an infrared remote control.

Another possibility for using the photosensors according to claim 12 is that the first and / or second photosensor is / is used as a smoke detector. Claim 13 relates to a practical embodiment of the basic proposed solution according to claim 1, which consists in that the control circuit part includes a transistor connected in series with the illumination LED, which - if the first photosensor falls below the

Minimum luminous flux or the minimum illuminance signals - is controlled by the control circuit in the spear state, whereby the self-test program detects an interruption failure.

Claim 14 relates to a practical realization of the basic proposed solution according to claim 2 or 3 and consists in that the control circuit part includes a transistor connected in series with the status LED, whose on-resistance by the variable parameter (photosensor current) of the first or further photosensor is determined, such that the lower the resistance and the lower the brightness of the status LED so, the greater the illuminance or the luminous flux of the incident on the first and second light sensor ambient light.

Embodiments of the invention will be described below with reference to the drawings.

Show it:

Figure 1 is a block diagram of an emergency unit connected to an operating device according to the prior art;

2 shows a first embodiment of the emergency light unit according to the invention with a Illumination LED, a first photosensor and a control circuit;

FIG. 3 shows a second embodiment of the invention, which differs from the embodiment shown in FIG. 2 in that a status LED is also provided here;

Figure 4 shows a third embodiment of the invention, which differs from the embodiment shown in Figure 3 in that a further photosensor is provided;

FIG. 5 shows a fourth embodiment of the invention, in which the illumination LED and the status LED cooperate with only one photosensor;

FIG. 6 shows the embodiment according to FIG. 2 in a somewhat more concrete embodiment;

Figure 7 is a somewhat more concrete embodiment of the control circuit part for a

Emergency lighting unit, in which the brightness of the status LED is adapted to the ambient light.

FIG. 1 shows an emergency lighting unit 3 according to the prior art, which comprises a lighting LED 4 and a status LED 7. The illumination LED 4 is used for emergency lighting. The status LED 7 is to indicate whether the illumination LED is functioning properly or is defective. The two LEDs 4 and 7 are supplied separately from an operating device 2 with operating voltages, which generates the operating device 2 from the voltage of a voltage source 1. In the present case, the voltage source 1 is drawn as a battery. In FIG. 1 and in the following FIGS. 2 to 5, only one illumination LED or one status LED is shown. In fact, however, in practice usually several LEDs are switched together.

Due to aging of the illumination LED, the luminous flux can become lower and fall below a required minimum value. When the required minimum illuminance falls below the emergency lighting functionality is not given.

FIG. 2 shows how this problem can be remedied. Here, the emergency light unit 3 has, in addition to a lighting LED 4, a first photosensor 6. The illumination LED 4 and the photosensor 6 are controlled by a control circuit part 5 belonging to the emergency light unit 3. The control circuit part 5 is in turn supplied by the operating device 2 with voltage and controlled.

The first photosensor 6 detects the brightness (directly or indirectly) of the illumination LED 4. The first photosensor 6 can be designed as an active component (photodiode) or as a passive component (photoresistor). In the case of training as a photodiode this generates when illuminated by a dependent on the illuminance or the luminous flux photocurrent, which is the control circuit part 5 is supplied. In the case of training as a photoresistor, the resistance is varied by the striking luminous flux or the illuminance. In one case, so the forms Photocurrent and in another case, the photoresistor one of the Lichtström or the illuminance of the

Lighting LED 4 dependent parameter, which is connected to the

Control circuit part 5 is passed. The control circuit part 5 now simulates one of those errors caused by the previously mentioned self-test program of the

Operating device can be detected. That's one

Open circuit failure (no power) or short circuit

(no voltage) at the output of the illumination LED 4.

FIG. 6 shows how an interruption error is simulated when a minimum luminous flux or a minimum illuminance of the illumination LED 4 is undershot. The first photosensor 6 is designed here as a photoresistor which forms a voltage divider with a further resistor 9. Notwithstanding Figure 2, two series-connected illumination LEDs 4 are provided in Figure 6, which are connected in series with a transistor 10. The base of transistor 10 is at the node of the voltage divider. When the light falling from the two illumination LEDs 4 on the first photosensor 6 falls below a minimum illuminance or a minimum luminous flux, the resistance of the photosensor 6 increases, with the result that the base voltage of the transistor 10 is reduced, and to the extent that the transistor 10 is practically non-conductive. The self-test program of the operating device evaluates this as an interruption defect. In this way, therefore, a brightness error of the two illumination LEDs 4 is detected.

The embodiment according to FIG. 3 serves to solve the following problem. The status LED must have a minimum light level to day and at high altitudes to be seen. Also, a sufficient light intensity is necessary to recognize it in addition to a point light source, which is the case with an LED and a compact lighting design. On the other hand, the status LED should not be too bright, as it could cause an undesirable lighting effect at night, for example.

In FIG. 3, the light of the status LED 7 is detected by the first light sensor 6. Alternatively, it is possible according to Figure 4, to provide a further light sensor 8, which serves to detect the light of the status LED 7, while the first light sensor 6 for detecting the light of the illumination LED 4 is used. According to FIG. 5, it is also possible to detect the light of both the illumination LED 4 and the light of the status LED 7 only by a light sensor 6. In this case, the transmission of light to the light sensor 6 must be time-division multiplexed. The evaluation by the control circuit part 5 is then also in time division.

Figure 7 now shows a practical embodiment which allows the light from two status LEDs 7a and 7b (7a is red and 7b is green) to be adapted to the ambient light. The ambient light is as well as the light of the two status LEDs 7a and 7b directed to the other photosensor 8, which in turn is designed as a photoresistor. Again, the photosensor 8 with a resistor 11 forms a voltage divider. Each of the two status LEDs 7a and 7b is connected in series with a transistor 12 or 13. The base terminals of the two transistors 12, 13 are located at the node of the voltage divider. As the ambient light becomes brighter, the resistance of the photosensor 8 decreases with the result that the base voltage of the two transistors 12, 13 increased. The flow resistance of the two transistors 12, 13 is thereby reduced, with the result that the two status LEDs 7a and 7b emit more light. The result is therefore that the light intensity of the two status LEDs 7a, 7b is adapted to the light intensity of the ambient light.

When "emergency unit" is mentioned above, this is also to be understood in that the control circuit part, the LEDs and the photosensors can be implemented as an integrated circuit and thus form a unit.

Claims

claims

1. emergency light unit (3) connected to one of a

Supply source (1) powered operating device (2) is connected and at least one illumination LED (4), characterized by, a directly or indirectly illuminated by the illumination LED (4) first photosensor (6), wherein at least one operating parameter (current , Voltage or resistance) of the photosensor (6) is changeable by the light falling on the photosensor (6), and a control circuit part (5) connected to the first photosensor (6) which evaluates the variable parameter to see if that of the lighting LED (4) emitted light - under direct lighting - a certain minimum luminous flux or - in indirect lighting - falls below a certain minimum illuminance. (Figures 2, 4.5 and 6.6)

2. Emergency light unit (3) connected to one of a

Supply source (1) powered operating device (2) is connected and at least one illumination LED (4) and at least one status LED (7), which indicates the correct or faulty operation of the illumination LED (4), characterized by a direct or indirectly from the status LED (7) and / or the ambient light illuminated first photosensor (6), at least one operating parameter (current, voltage or resistance) of the photosensor (6) being variable by the light falling on the photosensor (6) and a control circuit part (5) connected to the first photosensor (6) evaluating the variable parameter, wherein the control circuit part (5) evaluates the variable parameter of the first photosensor for the purpose of function control and / or brightness control of the status LED. (Figure 3)

3. emergency light unit (3) according to claim 1, with at least one status LED (7) indicating the correct or faulty operation of the illumination LED (4), characterized by a directly or indirectly from the status LED (7) and / or the ambient light illuminated further photosensor (8) which is connected to the control circuit part (5), wherein at least one operating parameter (current, voltage or resistance) of the other photosensor by the incident on the other photosensor (8) light is variable, and wherein the control circuit part (5) evaluates the variable parameter of the further photosensor (8) for the purpose of function control and / or brightness control of the status LED. (Figure 4)

4. emergency light unit (3) according to claim 1, with at least one status LED (7) indicating the correct or faulty operation of the illumination LED (4), characterized in that the first photosensor (6) is also directly or indirectly illuminated by the status LED (7) in order to monitor the operating state of the status LED (7) via the variable operating parameter, the illumination of the first photosensor ( 6) by the illumination LED (4) on the one hand and by the status LED (7) on the other hand by the control circuit part (5) in the time division multiplex, and wherein the evaluation of the variable

Operating parameters by the control circuit part (5) also takes place in this time division multiplex. (Figure 5)

5. Emergency lighting unit (3) according to claim 1, wherein the operating device (2) with a

Self-test program is equipped, which checks the supplied and controlled by him lighting LED (4) at regular intervals for a short circuit or interruption defect, characterized in that the control circuit part (5) artificially a short circuit or interruption defect on the illumination LED (4 ) When the first photosensor (6) detects an undershooting of the minimum luminous flux or the minimum illuminance, so that the operating device (2) can also detect the last-mentioned error conditions. (Figure 5)

6. emergency light unit (3) one of claims 2 to 5, characterized in that the illumination LED (4) and the status LED (7) are arranged spatially separated from each other, that they are perceived separately from the human eye for a given distance.

7. emergency light unit (3) according to one of claims 2 to 6, characterized in that the illumination LED (4) and the status LED (7) by a partition wall, preferably a reflector wall, are separated from each other, such that the Status LED (7) is shadowed by the illumination LED (4).

8. emergency light unit (3) according to claim 1, characterized in that the control circuit part (5) evaluates the variable parameter of the first photosensor (6) to the brightness of the status LED (7) in dependence on the brightness of the illumination LED ( 4) controls. (FIGS. 3, 4 and 5)

9. emergency light unit (3) according to claim 3, characterized in that a detected by the further photosensor (8) brightness defect of the status LED (7) causes the control circuit part (5) to control the lighting LED (4) so that this emits an optical signal, for example in the form of flashing.

10. Emergency lighting unit (3) according to one of the preceding claims, characterized in that, as the photosensor (4, 7) an actively working

Photodiode or a passive photoresistor is used, wherein as the supply voltage for the passive photoresistor, an external voltage, such as the supply voltage for the Illumination LED (4) or the supply voltage for the status LED (8) is used.

11. Emergency light unit (3) according to one of the preceding claims, characterized in that the first (4) and / or the second (7) photosensor in addition to the configuration, programming or addressing of the emergency light unit (3) by a separate light source, for example by an infrared remote control is used.

12. Emergency lighting unit (3) according to one of the preceding claims, characterized in that the first (4) and / or second (7) photosensor is additionally used as a smoke detector.

13. Emergency lighting unit (3) according to claim 1, characterized in that the control circuit part (5) with the illumination LED (4) connected in series transistor (10), which - when the first photosensor (6) falls below the Minimum luminous flux or the minimum illuminance signaled - is controlled by the control circuit (5) in the blocking state, whereby the self-test program detects an interruption failure. (Figure 6)

14. Emergency lighting unit (3) according to claim 2 or 3, characterized in that the control circuit part (5) with the status LED (7 a, 7 b) connected in series transistor (12, 13), whose forward resistance through the variable parameter of the first or further photosensor (6, 8) is determined, such that the greater the illuminance or the lower the brightness of the status LED (7a, 7b), the lower the on-resistance Luminous flux of the incident on the first and second light sensor (4, 8) ambient light. (Figure 7)

15. Emergency lighting unit (3) according to one of the preceding claims, characterized in that the control circuit part (5) and the LED / LEDs (4, 7) and / the photosensor / s (6, 8) are designed in integrated circuit.