Methods for controlling lighting devices and lighting equipment

Abstract

The invention relates to a method and a device for controlling a lighting device that can set regulatory and non-regulatory light output scenarios depending on signals received via a main signal line. The start of the signaling is signaled at a start time (t0) by a change from a second to a first logic level on the main signal line. If the lighting device is to set a non-regulatory light output scenario, the level of the main signal line changes from the first to a second logic level before the expiry of a waiting period (Tx).Subsequently, the lighting scenario to be set is signaled via PWM by switching between the second and first logic levels with a PWM modulation period. This signaling is then terminated when the main signal line remains at the first logic level for a period longer than the PWM modulation period. In contrast, a regulatory-mandated lighting scenario is activated if the main signal line does not switch to a second logic level before a waiting period (Tx) elapses. A non-regulatory lighting scenario is activated if the main signal line switches to a second logic level before a waiting period (Tx) elapses, corresponding to the PWM signaling of the lighting scenario to be set.

Description

Field of invention

[0001] The invention relates to a method for controlling a lighting device, wherein the lighting device can set regulatory prescribed light emission scenarios and non-regulatory prescribed light emission scenarios. General introduction

[0002] Independent lighting units in a car require signals from the respective main control unit to activate and execute the desired lighting function of the respective lighting unit. Typically, there are multiple requirements for the lighting function. For example, in the case of the rear lighting, the requirements might be: LEFT TURN, RIGHT TURN, BRAKE, TAIL LIGHT.

[0003] The above features are required by law, and to differentiate a solution, the OEM may request additional lighting animations such as “Leaving Home”, “Coming Home”.

[0004] The typical automaker does not want to provide additional electrical wiring for these stem-related lighting functions, as additional wiring would increase the cost and complexity of the wiring harness. Generally, automakers prefer PWM coding for the main signal functions of each lighting device. A control unit sends a PWM-coded command in the form of a PWM-coded signal to the respective lighting unit via a main signal line. The lighting unit's control unit detects the PWM-coded command in the PWM-coded signal and executes the detected command.

[0005] Each PWM signal on the main signal means that the lighting unit's control unit must recognize a pattern in the main signal's PWM-encoded signal. The problem is that recognizing this PWM-encoded command by the lighting unit's control unit requires processing time.

[0006] An automobile manufacturer's specification typically prescribes the time that may elapse between the start of the PWM-encoded command and the actual setting of the desired light output scenario by the lighting unit.

[0007] These specifications are typically available for the most important control functions.

[0008] In current implementations, providing additional command functions increases the processing time between the start of the PWM-encoded command and the setting of the desired light output scenario. This poses a particular problem if regulatory requirements are no longer met.

[0009] The control unit of each lighting unit repeatedly queries the signal to avoid false detections. This exacerbates the problem.

[0010] In today's low-end applications, signal detection is done as follows: The main light functions (e.g. TAIL, TURN, STOP,...) are triggered by switching static signals ON / OFF (HIGH / LOW).

[0011] To enable special functions (e.g. “coming home”, “leaving home”), either - uses a special cable to switch to animation mode or - modulates a PWM pattern onto a signal normally used for a main function to avoid additional wires.

[0012] For this purpose, a fixed time is reserved after the signal switches from low to high to detect a PWM pattern. If no valid PWM pattern is detected and the input signal remains HIGH, the main function switches ON. This wait for PWM pattern detection leads to an undesirable delay in switching on the main function.

[0013] From DE 10 2014 014 677 A1 a method for generating a PDM spread code modulated PDM output signal for use in a DC voltage supply and / or a DC / DC converter for supplying LEDs with electrical energy in motor vehicles is known. According to the technical teaching of DE 10 2014 014 677 A1, the generation of the PDM output signal is based on n PDM spreading codes, with n being a positive integer and n > 1. According to the technical teaching of DE 10 2014 014 677 A1, the spreading codes are arranged in a spreading code sequence of m consecutive PDM spreading codes of these n PDM spreading codes with a spreading code length that is equal to the PDM period, with m being a positive integer and m ≥ 1 and a spreading code period.According to DE 10 2014 014 677 A1, the generation of an optimized PDM spectrum of the PDM output signal comprises the steps of generating a first PDM signal with a PDM period and a PDM period duration and a duty cycle, generating one, in particular n - 1, further PDM signals by respectively delaying the first PDM signal and / or generating a respectively delayed first PDM signal. According to the technical teaching of DE 10 2014 014 677 A1, each i-th PDM signal generated in this way, with 1 < i ≤ n, is delayed by an i-th temporal offset compared to the first PDM signal, and each of the n PDM signals represents one of the n PDM spreading codes according to DE 10 2014 014 677 A1. Finally, according to DE 10 2014 014 677 A1, a k-th PDM signal is selected as the current PDM spread code signal from the n PDM signals depending on a selection signal and converted into the PDM output signal.However, the technical teaching of DE 10 2014 014 677 A1 does not disclose any approach to solving the problem presented here of undesired waiting for PWM pattern recognition and the problem of the resulting undesired delay in switching on the main function.

[0014] From document DE 11 2020 006 971 T5, a lighting control device is known that switches an input voltage to generate an output voltage and that supplies a drive current based on the output voltage to a lighting unit. According to the technical teaching of DE 11 2020 006 971 T5, a raw control signal is generated to alternately define a lighting duration and an extinguishing duration. According to the technical teaching of DE 11 2020 006 971 T5, a corrected control signal is generated based on the current through the lighting unit by correcting the raw control signal. According to the technical teaching of DE 11 2020 006 971 T5, a switching controller switches the input voltage during the lighting duration defined by the corrected control signal and interrupts the switching of the input voltage during the extinguishing duration defined by the corrected control signal.However, the technical teaching of DE 11 2020 006 971 T5 does not disclose any approach to solving the problem presented here of undesired waiting for PWM pattern recognition and the problem of the resulting undesired delay in switching on the main function. Task

[0015] The proposal therefore aims to reduce system costs and avoid significant delays in using PWM patterns on existing cabling.

[0016] This problem is solved by the technical teaching of the independent claims. Further embodiments may be the subject of subclaims. Solution to the task

[0017] The proposed method solves the problem of additional wiring or additional delay for PWM detection by separating the detection intelligence for the regulatory-required main functions of the lighting unit from the detection intelligence for the specific additional functions not required by regulations. The required functionality can be provided with the technical teaching presented here without additional wiring and with virtually no delay.

[0018] This ensures that the detection overhead for the special functions does not cause additional delay for the main functions.

[0019] One of the signaling methods for this approach is in Fig. 1 shown: Separating the detection intelligence for the regulatory and non-regulatory functions ensures that the detection overhead for the non-regulatory functions does not cause additional delay for the regulatory functions.

[0020] At the start of signaling, the control device switches the logic level of the main signaling line to a first logic value (e.g., "high"). If the vehicle's control device wants to activate a regulatory function of the lighting unit, the logic level of the main signaling line remains at this first logic level for longer than a time Tx. If the vehicle's control device wants to activate a non-regulatory function of the lighting unit, the logic level of the main signaling line remains at this first logic level for less than the time Tx and changes to the second logic level, for example, "low," before the time Tx has elapsed since the start of signaling.

[0021] If the logic level of the main signaling line remains at this first logic level for a period longer than a time Tx after the start of signaling by the control device, the control unit of the lighting unit recognizes that the regulatory function should be activated. Thus, the time delay between the start of signaling and the actual activation of the regulatory function of the lighting unit is limited to the time period Tx. Once the regulatory function is activated, the control unit of the lighting device recognizes that the lighting device should stop executing the regulatory function by the level on the main signaling line changing from the first logic value to the second logic value.

[0022] If the logic level of the main signaling line remains at this first logic level for a time shorter than a time Tx after the start of signaling by the control device, the lighting unit's control unit detects that a non-regulatory function is to be activated. Typically, the lighting unit's control unit can use the PWM signal to identify the type of non-regulatory function the lighting unit is to perform. This signaling and detection process takes time. Thus, the time delay between the start of signaling and the actual activation of the lighting unit's regulatory function is no longer limited to the time Tx. Rather, it depends significantly on the type and length of the longest PWM sequence.Once the non-regulatory function has been activated, the control device of the lighting device recognizes that the lighting device should stop executing the non-regulatory function because the level on the main signal line only changes from the first logical value to the second logical value after a longer period of time.

[0023] By specifying a fixed time Tx after which the main (regulatory) function is triggered, the entire time required to reliably detect the pattern for a special (non-regulatory) function is avoided as a delay or latency added to the main function. This scheme allows multiple special (non-regulatory) functions on one signal line, each dedicated to a regulation function based on the ability to detect multiple PWM signatures (patterns). There is no additional overhead for the time until the main regulation function is activated.

[0024] The document presented here therefore describes a method for controlling a lighting device, whereby the lighting device can set regulatory prescribed light emission scenarios and non-regulatory prescribed light emission scenarios.

[0025] The lighting device preferably adjusts the light emission scenarios depending on signaling via a main signal line.

[0026] The proposed method preferably comprises the steps: - signaling the start of the signaling at a start time (t0) by means of a change from a second logic level to a first logic level on the main signal line; - changing the level of the main signal line from the first logic level to a second logic level before the expiry of a waiting time (Tx) beginning with the start time (t0), if the lighting device is to set a light emission scenario that is not prescribed by regulation, and subsequent PWM signaling of the light emission scenario to be set by PWM-modulated switching between the second logic level and the first logic level with a PWM modulation period and terminating the PWM signaling of the light emission scenario to be set by keeping the level of the main signal line at the first logic level for a time longer than the PWM modulation period; - Activation of a regulatory light emission scenario if the level of the main signal line has not changed to a second logic level before the expiry of a waiting time (Tx); - Deactivation of the regulatory light emission scenarios if the level of the main signal line has not changed to a second logic level before the expiry of a waiting time (Tx) and if the level of the main signal line has changed to a second logic level after the expiry of a waiting time (Tx); - Activation of a light emission scenario not prescribed by regulation if a change in the level of the main signal line to a second logic level occurred before the expiry of a waiting time (Tx), according to the PWM signaling of the light emission scenario to be set; - Deactivation of the light emission scenarios not prescribed by regulation if a change in the level of the main signal line to a second logic level occurred before the expiry of a waiting time (Tx) and PWM signaling of the light emission scenario to be set has ended and if a change in the level of the main signal line from the first logic level to a second logic level occurs after the end of the PWM signaling of the light emission scenario to be set.

[0027] A corresponding lighting device corresponds to this method. The lighting device is preferably configured to be able to set regulatory-prescribed light emission scenarios and non-regulatory light emission scenarios. Typically, the lighting device sets the light emission scenarios depending on signaling via a main signal line. The lighting device typically detects the start of a signaling at a start time (t0) by detecting a change from a second logic level to a first logic level on the main signal line. The lighting device preferably activates a regulatory-prescribed light emission scenario upon expiration of a waiting time (Tx) from the start time (t0) if no change in the level of the main signal line to a second logic level has occurred before the expiration of the waiting time (Tx) since the start time (t0).The lighting device deactivates the regulatory light emission scenario again with the change of the level of the main signal line to a second logical level after the waiting time (Tx) has elapsed, if there has been no change of the level of the main signal line to a second logical level before the waiting time (Tx) has elapsed since the start time (t0), i.e. the regulatory light emission scenario is activated.

[0028] The lighting device activates a light emission scenario not prescribed by regulation if a change in the level of the main signal line from the first logic level to a second logic level occurs before the expiry of a waiting time (Tx) beginning with the start time (t0) and if a PWM signaling of the light emission scenario to be set subsequently occurs by PWM-modulated change between the second logic level and the first logic level with a PWM modulation period and if a signaling of the end of the PWM signaling of the light emission scenario to be set occurs by the level of the main signal line remaining at the first logic level for a time longer than the PWM modulation period (T PWM ) or when the end of the PWM signaling of the light emission scenario to be set is indicated by the elapse of a signaling time (T PWMmax) since the start time (t0). The lighting device deactivates the non-regulatory light emission scenario again if the level of the main signal line changes to a second logic level before the expiration of a waiting time (Tx) and the PWM signaling of the light emission scenario to be set has ended, and if the level of the main signal line changes from the first logic level to a second logic level after the end of the PWM signaling of the light emission scenario to be set. List of characters Fig. Figure 1a shows a sketched signal for signaling a light emission scenario that is not prescribed by regulation. Fig. Figure 1b shows a sketched signal for signaling a regulatory prescribed light emission scenario. Description of the figuresFigure 1

[0029] Fig. Figure 1a shows a sketched signal for signaling a non-regulatory light emission scenario. With the rising edge from a second logic level to a first logic level on the main signal line, the vehicle's control device signals the start time t0 to the lighting unit's control device. Typically, the lighting unit's control device starts a time counter upon signaling the start time t0. If a change from the first logic level to the second logic level occurs within the waiting time Tx by means of a falling edge, the lighting unit's control device recognizes that a non-regulatory light scenario is to be set. However, which non-regulatory light scenario is to be set is still open at this point. This information is provided by the subsequent PWM signal.This PWM signaling of the non-regulatory lighting scenario to be set ends either after a predetermined period of time has elapsed or at a PWM signaling end time (T. PWMmax ) or by the level of the main signal remaining constant for longer than the PWM period T PWM remains at the first logical level. The signaling of the deactivation of the non-regulatory lighting scenario is carried out in the example of Fig. 1a by a falling edge from the first logical level to the second logical level.

[0030] Fig. Figure 1b shows a sketched signal for signaling a regulatory lighting scenario. With the rising edge from a second logic level to a first logic level on the main signal line, the vehicle's control device signals the start time t0 to the lighting unit's control device. Typically, the lighting unit's control device restarts a time counter upon signaling the start time t0. If there is no change from the first logic level to the second logic level by means of a falling edge within the waiting time Tx, the lighting unit's control device detects that a regulatory lighting scenario should be set. Therefore, the lighting device typically sets and activates this regulatory lighting scenario upon expiration of the waiting time Tx.The signaling of the deactivation of the regulatory lighting scenario is shown in the example of . Fig. 1b by a falling edge from the first logical level to the second logical level. List of reference symbols and abbreviations PWM pulse width modulation; t0 start time; T PWM PWM period; T PWMmax PWM signaling end time; Tx Wait Time

Claims

[1] Method for controlling a lighting device, whereby the lighting device can set regulatory prescribed light emission scenarios and whereby the lighting device can set light emission scenarios that are not prescribed by regulations and wherein the lighting device adjusts the light emission scenarios depending on signals via a main signal line, with the steps: Signaling the start of the signaling at a start time (t0) by means of a change from a second logic level to a first logic level on the main signal line; Changing the level of the main signal line from the first logic level to a second logic level before the expiry of a waiting time (Tx) beginning with the start time (t0), if the lighting device is to set a light emission scenario that is not prescribed by regulation, and subsequent PWM signaling of the light emission scenario to be set by PWM-modulated switching between the second logic level and the first logic level with a PWM modulation period and terminating the PWM signaling of the light emission scenario to be set by keeping the level of the main signal line at the first logic level for a time longer than the PWM modulation period; Activation of a regulatory light emission scenario if the level of the main signal line has not changed to a second logic level before the expiration of a waiting time (Tx); Activation of a non-regulatory light emission scenario if the level of the main signal line changes to a second logic level before a waiting time (Tx) has elapsed, according to the PWM signaling of the light emission scenario to be set. [2] A method for controlling a lighting device according to claim 1, comprising the additional steps of: Deactivation of the regulatory prescribed light emission scenarios if the level of the main signal line has not changed to a second logic level before the expiration of a waiting time (Tx) and if the level of the main signal line has changed to a second logic level after the expiration of a waiting time (Tx) and / or Deactivation of the light emission scenarios not prescribed by regulation if a change in the level of the main signal line to a second logic level occurred before the expiry of a waiting time (Tx) and a PWM signaling of the light emission scenario to be set has ended and if a change in the level of the main signal line from the first logic level to a second logic level occurs after the end of the PWM signaling of the light emission scenario to be set. [3] Lighting device, wherein the lighting device is designed to be able to set regulatory prescribed light emission scenarios, and wherein the lighting device is designed to be able to set light emission scenarios that are not prescribed by regulations, and wherein the lighting device is configured to adjust the light emission scenarios depending on signals via a main signal line, wherein the lighting device is configured to detect the start of a signaling at a start time (t0) by detecting a change from a second logic level to a first logic level on the main signal line, and wherein the lighting device is configured to activate a regulatory prescribed light emission scenario upon expiration of a waiting time (Tx) if no change in the level of the main signal line to a second logic level occurs before expiration of the waiting time (Tx), and wherein the lighting device is configured to activate a light emission scenario not prescribed by regulation, - if a change in the level of the main signal line from the first logic level to a second logic level occurs before the expiry of a waiting time (Tx) beginning with the start time (t0) and - if a PWM signalling of the light emission scenario to be set is subsequently carried out by PWM-modulated switching between the second logic level and the first logic level with a PWM modulation period and - if a signalling of the end of the PWM signalling of the light emission scenario to be set is signalled by the level of the main signal line remaining at the first logic level for a time longer than the PWM modulation period (T PWM ) or when the end of the PWM signaling of the light emission scenario to be set is indicated by the elapse of a signaling time (T PWMmax ) since the start time (t0). [4] Lighting device according to claim 3, wherein the lighting device is configured to deactivate the regulatory prescribed light emission scenario with the change of the level of the main signal line to a second logic level after expiration of the waiting time (Tx), if no change of the level of the main signal line to a second logic level occurred before expiration of the waiting time (Tx), and / or wherein the lighting device is configured to deactivate the non-regulatory light emission scenario if a change in the level of the main signal line to a second logic level occurred before the expiration of a waiting time (Tx) and the PWM signaling of the light emission scenario to be set has ended, and if a change in the level of the main signal line from the first logic level to a second logic level occurs after the end of the PWM signaling of the light emission scenario to be set.

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