REGULATION OF SEQUENTIALLY OPERATING LIGHT SOURCE AND DEVICE FOR CARRYING OUT THE METHOD

Abstract

The present invention refers to a method and a device for sequentially operating light source, in particular a lighting system for signalizing a change of driving direction of a motor vehicle, comprising a plurality of light emitting diodes (LED) connected in series, said diodes can be activated in a pre-determined sequence within a required time frame t.sub.0. The method comprises activating within a required time frame (t.sub.0) a sequential operation of a plurality of LEDs, wherein the operation of the first LED in the plurality of LEDs and operation of the last LED in the plurality of LEDs is carried out within an actual time frame (t.sub.1) of operation. The method further comprises activating after lapse of a safety time frame (t.sub.2) of all LEDs (1.sub.1, 1.sub.2 . . . 1.sub.n) simultaneously.

Claims

1. A method for sequentially operating light source on a vehicle, in particular a lighting system for signalizing a change of driving direction of a motor vehicle, comprising a plurality of light emitting diodes (LED) (1.sub.1, 1.sub.2. . . 1.sub.n) connected in series, said diodes can be activated in a pre-determined sequence within a required time frame (t.sub.0), characterized in that, the method comprises the following steps: a) activating within a required time frame (t.sub.0) a sequential operation of a plurality of LEDs (1.sub.1, 1.sub.2 . . . 1.sub.n), wherein the operation of the first LED (1.sub.1) in the plurality of LEDs and operation of the last LED (1.sub.n) in the plurality of LEDs is carried out within an actual time frame (t.sub.1) of operation; b) activating by means of a reserve security element and after lapse of a safety time frame (t.sub.2) of all LEDs (1.sub.1, 1.sub.2 . . . 1.sub.n) simultaneously.

2. The method according to claim 1, wherein the required time frame (t.sub.0), the actual time frame (t.sub.1) and the safety time frame (t.sub.2) are equal.

3. The method according to claim 1, wherein said actual time frame (t.sub.1) is at most equal to or smaller than the required time frame (t.sub.0).

4. The method according to claim 1, wherein said safety time frame (t.sub.2) is equal to or smaller than the required time frame (t.sub.0), but larger than the actual time frame (t.sub.1) of the activation of all LEDs (1.sub.1, 1.sub.2 . . . 1.sub.n).

5. A device for carrying out a method according to claim 1, characterized in that, the device comprises: a) a plurality of light emitting diodes (1.sub.1, 1.sub.2 . . . 1.sub.n) connected in series; b) a feeding device which that controls at least one LED from the plurality of LEDs (1.sub.1, 1.sub.2. . . 1.sub.n); c) a thermal protection element the resistance thereof depends on temperature; d) an excess voltage protection element; e) a security element, which in case that at least one LED (1.sub.1, 1.sub.2. . . 1.sub.n) from the plurality of LEDs fails provides for that a driver is alerted about the failer; f) a timer and shift element, which provides for a sequential activation of LEDs (1.sub.1, 1.sub.2 . . . 1.sub.n); g) a control element, which connects all aforementioned elements and provide for carrying out of respective functions thereof; and h) a reserve security element, which is associated with the control element and takes care of the operation when the failure occurs and, respectively, when any of the components fails.

6. The device according to claim 5, wherein the number n of LEDs is selected as an even number.

Description

EXAMPLE 1

Failure of the Timer and Shift Element

[0013] When the direction indicator is turned on the first LED 1.sub.1 in the plurality of LEDs is always activated, whereas remaining LEDs 1.sub.2, 1.sub.3 . . . 1.sub.n are not activated due to said non-operation of the timer and shift element 7. In this particular case, said reserve security element 10 provides for by means of overriding all other circuits and, components, that all LEDs are activated simultaneously within the safety time frame t.sub.2t.sub.0 oz. t.sub.2t.sub.1.

EXAMPLE 2

Failure of One of the LEDs

[0014] If anyone of LED 1.sub.1, 1.sub.2 . . . 1.sub.n from the plurality of LEDs fails, such as LED 1.sub.3 for instance, the security element 6 stores the information about a limited failure of the LED 1.sub.3 and all LED are not activated until the end of the sequence. The LEDs remain non-activated for the entire time frame within which the direction indicator is supposed to operate. The diagnostic takes place since the LEDs are not active and, thus, there is no power consumption and, respectively, the power consumption decreases.