Device for automatically switching lighting devices in vehicles

• US 6,759,761 B1
• Filed: 02/06/2002
• Issued: 07/06/2004
• Est. Priority Date: 01/12/2000
• Status: Expired due to Fees

• Current Assignee: Robert Bosch GmbH
• Original Assignee: Robert Bosch GmbH
• Inventors: Blizke, Henry, Meier, Hans, Schmitt, Patrick, Burkart, Manfred, Hodapp, Bruno, Hog, Norbert, Pientka, Rainer
• Primary Examiner(s): TOATLEY, GREGORY J
• Application Number:
  US09/936,700
• Time in Patent Office: 881 Days
• Field of Search: 307/10.8, 315/77, 315/82, 315/153
• US Class Current: 307/10.8
• CPC Class Codes: B60Q 1/1423 Automatic dimming circuits, i.e. switching between high beam and low beam due to change of ambient light or light level in road traffic
• CPC Class Codes: B60Q 2300/112 Vehicle speed
• CPC Class Codes: B60Q 2300/312 Adverse weather
• CPC Class Codes: B60Q 2300/314 Ambient light
• CPC Class Codes: B60Q 2300/337 Tunnels or bridges
• CPC Class Codes: H05B 45/12 using optical feedback
• CPC Class Codes: H05B 45/18 using temperature feedback
• CPC Class Codes: H05B 47/11 by determining the brightness or colour temperature of ambient light
• CPC Class Codes: Y02B 20/40 Control techniques providing energy savings, e.g. smart controller or presence detection

Abstract

The device has a sensor device (20) and an evaluation device (30). The sensor device (20) has a global sensor (22), by which the general light intensity in the surroundings of the vehicle is detected nondirectionally, and a directional sensor (24), by which the light intensity is detected directionally in the travel direction of the vehicle. By the evaluation device (30), the signals (S1, S2) of the sensors (22, 24) of the sensor device (20) are compared with threshold values (SE), and if at least one threshold value (SE) is undershot, the lighting devices (10, 12) are switched on. A temperature measuring instrument (32) for detecting the temperature of the sensor device (20) is also provided, which supplies the evaluation device with a signal (ST) about the temperature. In the evaluation device (30), temperature-dependent basic signals (S10, S20) that the sensors (22, 24) generate without light incidence are stored in memory. By means of the evaluation device (30), a correction of the current signals (S1, S2) of the sensors (22, 24) of the sensor device (20) and/or of the threshold mn values (SE) is effected as a function of the basic signals (S10, S20).

Claims

1. A device for automatically switching lighting devices in a vehicles, comprising,

a sensor device (20) for detecting the light intensity in surroundings of the vehicle;

at least one global sensor (22) provided in the sensor device for nondirectonally detecting the general light intensity in the surroundings of the vehicle;

at least one directional sensor (24) provided in the at least one global sensor for directionally detecting the light intensity at least approximately in the travel direction (14) of the vehicle;

an evaluation device (30) for comparing the current signals (S1, S2) of the sensors (22, 24) of the sensor device (20) with threshold values (SE), wherein if at least one of the threshold values (SE) is undershot, the lighting devices (10, 12) are switched on,

wherein at least indirectly, the current temperature of the sensor device (20) is detected and a signal (ST) pertaining to the current temperature is delivered to the evaluation device (30)

a memory, wherein in the evaluation device (30), temperature-dependent basic signals (S10, S20) of the sensors (22, 24) of the sensor device (20) are stored in the memory without incidence of light, and wherein by means of the evaluation device (30), a correction of the current signals (S1, S2) of the sensors (22, 24) of the sensor device (20) and/or of the threshold values (SE) is effected in accordance with the basic signals (S10, S20).

2. The device of claim 1, wherein by means of the evaluation device (30), a rate of change (dS/dt) of the signals (S2, S2) of the sensor device (20) are ascertained, and wherein the threshold values (SE) are varied as a function of the rate of change (dS/dt) of the signals (S1, S2), in such a way that at a high rate of change (dS/dt), the threshold values (SE) are higher than at a low rate of change (dS/dt).

3. The device of claim 1, wherein by means of the evaluation device (30), the threshold values (SE) are varied as a function of the absolute values of the signals (S1, S2) of the sensor device (20), in such a way that for a signal (S1, S2) that is decreasing from a high absolute value, the threshold values (SE) are higher than for a signal (S1, S2) that is decreasing from a low absolute value.

4. The device of claim 1, wherein the evaluation device (30) is supplied with a signal (SG) for a current speed of the vehicle, and wherein the processing of the signals (S1, S2) of the sensors (22, 24) of the sensor device (20) by the evaluation device (30) is effected in clocked fashion as a function of the speed of the vehicle, in such a manner that the processing at high speed is done at a higher dock frequency than at low speed.

5. The device of claim 4, wherein the clock frequency is varied as a function of the speed in such a way that a distance the vehicle covers between successive processing cycles is approximately constant.

6. The device of claim 1, wherein a further sensor device (34) for detecting precipitation is provided, wherein a signal (SR) is generated at least indirectly by said further sensor device and delivered to the evaluation device (30), and wherein by the evaluation device (30), a variation in the threshold values (SE) is effected in such a manner that the threshold values (SE) are higher when precipitation is present than when precipitation is absent.

7. The device of claim 6, wherein the signal (SR) generated at least indirectly by the further sensor device (34) is dependent on the intensity of the precipitation, and wherein by means of the evaluation device (30), a variation in the threshold values (SE) is effected in such a manner that the threshold values (SE) are higher at high intensity of the precipitation than at low intensity of the precipitation.