AT517308A1 - Luminous structure for vehicles - Google Patents

Abstract

Luminous structure (1) for vehicles with a two or more partial luminous surfaces (A1, A2, A3 and A4), which is arranged at an externally visible position of the vehicle, wherein the partial luminous surfaces light sources (L1, L2, L3 and L4 ), which, driven by a control device (2), in their intensity and / or color are temporally dependent changed and the drive means (2) is adapted to the individual light sources (L1, L2, L3 and L4) in dependence predetermined, definable upper and lower limit values (Imin (), Imax ()) for the total intensity (Iges (, t)) of the luminous structure (1) with the partial luminous surfaces (A1, A2, A3 and A4) to control.

Description

P14274

The invention relates to a lighting structure for vehicles with a two or more partial lighting surfaces, which is arranged at an externally visible position of the vehicle, wherein the partial lighting surfaces light sources are assigned, which, driven by a drive means, in their intensity and / or color are temporally dependent changeable.

The partial light areas may together represent a signal light or illumination function, e.g. Daytime running lights, headlights, direction indicators, etc., but also dipped beam and cornering lights are possible in principle.

A luminous structure of this type has become known, for example, from the applicant's published application AT522545. This known device serves as a status indicator for the state of an operationally relevant component of a motor vehicle, wherein at one of the externally visible position of the vehicle a light source fed by at least two light sources is arranged and the light sources is assigned a drive circuit, which is adapted to the light sources in dependence to control a state signal representative of the state of the operational component in such a way that the luminance and / or color of the luminous structure indicates the state of the component in the manner of a scale long ago.

In the construction of vehicles, especially automobiles, more emphasis is placed on a pleasing and yet eye-catching appearance, which also affects the design of headlamps and signal lights, on the one hand must meet the lighting and legal requirements, but on the other hand also different aesthetic aspects should correspond. Frequently, LEDs are used, e.g. in cooperation with optical fibers produce luminous surfaces which are arranged at such a position, which is visible from the outside. For example, such luminous surfaces can be arranged at headlights or be used for direction indicator. It is known that the light sources are controlled in their brightness, for example, be dimmed, such as current limiting or PWM circuits.

The term "luminous surfaces" used in the following for the sake of simplicity is to be understood in the context of the invention as representing the light-emitting surfaces recognizable by a viewer, which may be planar but may also be represented by one or more reflectors or other structures, such as of optical elements, such as lenses, mirrored and / or grained panel parts or reflectors.

A problem for the designer are legal requirements which specify a minimum and / or maximum intensity distribution or specific minimum / maximum intensity values at predetermined measuring points of a specific luminaire. These must also be met in lighting devices whose partial luminous surfaces are controlled in their brightness by correspondingly driving associated individual luminous surfaces in a time-variable manner. Usually, an intensity distribution is prescribed by law or a distribution of illuminance on a given illuminated area, e.g. a wall 25 meters away.

An object of the invention is to provide a luminous structure in which this problem is solved.

This object is achieved with a lighting structure of the type mentioned, in which according to the invention, the drive means is adapted to the individual light sources in

To control dependence on predetermined, definable upper and lower limits for the total intensity of the lighting structure with the partial luminous surfaces.

In this way, the designer has the freedom to individually control individual light sources or illuminated areas in a wide range in terms of their brightness or color, as long as only the total brightness is within certain predeterminable limits.

An expedient variant is characterized in that the drive device is set up to control the individual light sources in compliance with a predetermined and definable minimum luminous total area of the lighting structure. As a result, it is also possible to meet the often existing requirement that a minimum luminous area of the luminous structure must be present and illuminated.

In an easily realizable and cost-effective variant, it may be advantageous if the upper and lower limits for the total intensities of all partial luminous areas and / or the size of the minimum luminous total area of the luminous structure are stored in a memory.

In another embodiment, the drive device may be configured to control the rate of change of the control of the individual light sources in terms of intensity and / or color as a function of their supplied, the driving situation parameters.

Furthermore, it may be expedient for the control device to be set up to control the individual light sources with regard to their intensity and / or color as a function of the parameters relating to the driving situation within the given definable upper and lower limit values for the total brightness of all partial illuminated areas ,

In this case, it is of particular advantage if the parameters relating to the driving situation are the vehicle speed and / or the ambient light and / or location coordinates and / or values of sensor means which detect the driver's condition.

The invention together with further advantages is explained in more detail below by way of example embodiments, which are illustrated in the drawing. In this show

1 shows, with reference to a schematic block diagram, for example, the actuation of a luminous structure having four partial luminous areas,

2 a to 2 c, for example, diagrams of intensity distributions,

3 is a diagram with a set of measuring points,

4 shows a time diagram with an exemplary course of the overall intensity,

5 shows four luminous partial segments of a luminous structure according to the invention,

6 shows, for example, time profiles of time-dependent scaling factors of individual light segments, FIG. 7 shows an example of another control of four light sources, and FIG. 8 shows the time profile of the scaling factors associated with FIG.

1 shows a luminous structure 1 with four partial luminous surfaces Ai, A2, A3 and A4, wherein in the present case these luminous surfaces are illuminated via light guides Fi, F2, F3 and F4 by light sources Li, L2, L3 and L4. The light sources may be, for example, light-emitting diodes, but the light sources may also be present directly in the light areas, for example in embodiments with luminescence or OLED technology.

The light sources are driven by a drive circuit 2, which may be a microcomputer, for example. The drive circuit 2 is assigned a memory 3, and from an on-board computer 4, the drive circuit 2 receives signals from a speed sensor 5, a brightness sensor 6 and a navigation system 7.

The drive circuit 2 is now set up to operate the individual light sources L2, L2, L3 and L4 as a function of predetermined upper and lower limit values stored in the memory 3 for the total intensity of the luminous structure 1 with the partial luminous areas Ai, A2, A3 and A4 head for. There are usually statutory requirements, which specify a minimum and / or maximum brightness of a specific luminaire or its entire luminous area and which must also be met in lighting devices whose partial luminous surfaces are controlled by appropriate driving associated individual illuminated surfaces temporally variable in their brightness. These criteria can be met thanks to the invention, but the designer has the freedom to individually control individual light sources or lighting surfaces in a wide range in terms of brightness or color, since it is ensured that the total brightness is within the prescribed limits.

The drive circuit 2 is further also adapted to drive the individual light sources Li, L2, L3 and L4 in compliance with a predetermined and definable minimum luminous total area of the lighting structure 1, wherein the size of the minimum luminous total area is stored in the memory 3.

Furthermore, the drive circuit 2 is set up to control the rate of change of the activation of the individual light sources Li, L2, L3 and U in terms of intensity and / or color as a function of their parameters relating to the driving situation. These parameters v, Ev, GPS may, as in the example shown, be the vehicle speed provided by the sensor 5, and / or the external brightness provided by the sensor 6 and / or the position of the vehicle supplied by the navigation system 7 derived location coordinates derived.

Thanks to the invention, the legally required light distribution can be fulfilled in any operating state and a light distribution (intensity or illuminance distribution) which is as constant as possible while the luminance distribution is varied over time (appearance of the light function) is ensured. The individual light sources can be controlled according to a predetermined, time-varying pattern, which can be done freely programmable or permanently programmed.

As already mentioned, the rate of change over time can be influenced by various factors:

Little dynamic e.g. on highway driving at high speed; influenced by the steering angle or GPS information.

Dynamic in city traffic, e.g. at speeds below 70 km / h, influenced by road light detection or GPS information for city traffic, depending on the driver's mental / attention / fatigue state as detected by sensor systems.

When the vehicle is at a standstill: changes can also be made dynamically here, for example when the vehicle is locked or unlocked, and also with a personalization of the driver (young, old, male, female, playful, etc.).

Analogous to the control of the rate of change by the drive circuit 2, the individual light sources U, L2, L3 and L4 can be controlled with respect to their intensity and / or color in dependence on their supplied, the driving situation parameters. In both cases, of course, this control takes place in the context of the upper and lower limit values stored in the memory 3 for the total brightness of all partial luminous areas Ai, A2, A3 and A4. Likewise, the stored in the memory 3 size of the minimum luminous total area is maintained.

The necessary algorithm for the control can be realized in principle in the form of an explicit analog or digital control which can result in a cost reduction. In this sense, then the function of the drive means to understand. For even greater flexibility in the control, it may be advantageous to use a μ-controller control. This is particularly useful if other control variables such as. Speed, brightness, mental state of the driver or the like should be included in the algorithm. In this case, the drive device is accordingly equipped with at least one μ-controller. The individual parameters, e.g. Current intensity of the respective partial luminous surfaces are stored in this case in the memory of the μ-controller, see the memory 3 of FIG. 1, which is shown as representative of at least one memory. Another advantage is that such controls can be used as a standard in different projects and thus cost advantages can be achieved by higher volumes, without losing flexibility in the design of the driving algorithm.

In the following, examples for determining the drive values for the light sources are shown, wherein reference is made to FIGS. 2a to 2c.

The representation of the respective intensity distribution of a partial luminous surfaces Ai, A2, A3 and A4 is shown below in an angular coordinate system. In FIG. 2, h denotes the horizontal angle and v the vertical angle. The crossing point is usually referred to in vehicle lighting technology with HV - usually the point to which the direction of movement of the vehicle is directed. Each point in the angle diagram can be defined by a vector hv. With Ii (hv), the light intensity of the ith subarea at the point vector hv is vector hv.

A function a; (t), whose value may be between 0 and 1, and which may also be referred to as a time-dependent scaling factor of each partial light area, determines the time dependence of each i-th light distribution such that the sum of all light intensity distributions in mathematical form is as follows can be defined: lges (hv, t) = Yi = 1aMMhv)

In light vehicle technology, upper and lower intensity limits are specified for different light functions at specific measuring points, which are determined both by customer wishes and by legal requirements within which the respectively measured value must lie. This set of measuring points is, see Fig. 3, denoted by a. The upper and lower limits at the measuring point are denoted by lmin (7ni) and lmax (7ni).

It is now a set of partial light distributions to make and the scaling factors ai (t) are to be defined such that for all measuring points m, at each time t, the following inequality is satisfied

Imin (ftti) <Iges (rrii, t) <lmax (tri,)

In Fig. 4, an exemplary intensity profile satisfying the above inequality is shown.

On the other hand, Fig. 5 shows, for example and schematically, four luminous sub-segments of a daytime running lamp, with L, (öc, t) the luminance distributions changing with time t, thus the respective appearance of e.g. are designed as optical fiber sub-segments, from an observer position «are designated. The segments generate those intensity distributions I, (hv) which correspond to the legal requirements and customer specifications.

Two possible courses of the functions ai (t) to a4 (t) of four individual light sources LI..14, which are embodied, for example, as light-emitting diodes and can correspond to the light sources of the arrangement according to FIG. 1, are shown in FIG first example with continuous and the second example is shown by dashed lines.

7 schematically shows another embodiment of the invention in which the drive circuit 2 activates two series circuits of light sources L1 + L3 and L2 + L4, respectively, and each series circuit is assigned a function b (t) whose value is again between 0 and 1 can, and which determines the temporal dependence of each of the two light distributions. An exemplary course of these functions b, (t) is shown in FIG. 8.

Claims (6)

claims A lighting structure (1) for vehicles having a two or more partial luminous surfaces (Ai, A2, A3 and A4) arranged at an externally visible position of the vehicle, wherein the partial luminous surfaces have light sources (Li, L2, L3 and A4) U), which, controlled by a control device (2), in their intensity and / or color are temporally dependent changed, characterized in that the drive means (2) is adapted to the individual light sources (Li, L2, L3 and L4) as a function of predetermined, definable upper and lower limit values (lmrn (TrZi), lmax (ttti)) for the total intensity (lges (hv, t)) of the luminous structure (1) with the partial luminous surfaces (Ai, A2, A3 and A4). 2. Luminous structure (1) according to claim 1, characterized in that the drive device (2) is adapted to drive the individual light sources (Li, L2, L3 and L4) while maintaining a predetermined and definable minimum luminous total area of the lighting structure. 3. Luminous structure (1) according to claim 1 or 2, characterized in that the upper and lower limits for the total intensities of all partial luminous areas and / or the size of the minimum luminous total area of the luminous structure are stored in a memory (3). 4. lighting structure (1) according to claim 1, characterized in that the drive means is adapted to the rate of change of the control of the individual light sources (Li, L2, L3 and L4) with respect to intensity and / or color depending on the supplied, the driving situation To control parameters. 5. Luminous structure (1) according to claim 1, characterized in that the drive means is adapted to the individual light sources in terms of their intensity and / or color depending on the driving situation related parameters (v, Ev, GPS) within the given , to set definable upper and lower limits for the total brightness of all partial luminous surfaces. 6. lighting structure (1) according to claim 4 or 5, characterized in that the driving situation related parameters are the vehicle speed and / or the ambient light and / or location coordinates and / or values of the condition of a driver detecting sensor means.