Vehicle headlight beam controls

• US 7,755,294 B2
• Filed: 04/04/2008
• Issued: 07/13/2010
• Est. Priority Date: 04/05/2007
• Status: Active Grant

• Current Assignee: Jaguar Land Rover Limited (TATA Motors Limited)
• Original Assignee: Jaguar Cars Limited (TATA Motors Limited)
• Inventors: Betts, Peter Howard, Shelton, Richard Dennis, Smith, David Philip
• Primary Examiner(s): Vu; David Hung
• Application Number:
  US12/062,983
• Publication Number:
  US 20080246404A1
• Time in Patent Office: 830 Days
• Field of Search: 315/82, 315/76, 315/83, 315/80, 315/77, 315/149, 315/150, 315/155, 315/156, 315/158, 315/159, 307/10.8
• US Class Current: 315/80
• 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 1/1476 comprising switch controlling means located near the free end of the lever, e.g. press buttons, rotatable rings

Abstract

A method of manually overriding automatic activation of an automatic headlight control system for a motor vehicle, headlamps operable in a high beam state and a low beam state, a high/low beam switch movable from a neutral position to a latched position and from a neutral position to a non-latched position for controlling the state of the headlamps and a headlamp on/off switch comprising a multi-position switch with at least a selectively automatic headlamp position is disclosed. The system includes forward-facing sensor for collecting light emanating from for instance a second vehicle, and a controller for controlling, when the headlamp switch is detected as being in the automatic headlamp position, the headlamp states as a function of the sensed intensity of the beam of light emanating from said second vehicle. The method comprises the steps of: monitoring the states of the headlamps when the headlamp on/off switch is in the automatic position, causing the controller to initiate an override mode if the high beam states is detected (step 230) and said high/low beam switch is detected as moved from the neutral position to the non-latched position whereupon the controller changes the headlamps to the Low state (step 260) when the High/Low beam switch is subsequently released to the neutral position. Such a method ensures the use of conventional stalk.

Claims

1. A method of manually overriding automatic activation of an automatic headlight control system for a motor vehicle having headlamps operable in a high beam state and a low beam state, a high/low beam switch for controlling the state of the headlamps and a headlamp on/off switch comprising a multi-position switch with at least a selectable automatic headlamp position, the system including a forward-facing sensor for collecting light emanating from a light source in front of the vehicle, an ambient light sensor for collecting ambient light and a controller for controlling, when the headlamp switch is detected as being in the automatic headlamp position, the headlamp state as a function of the sensed intensity of the beam of light source, the high/low beam switch being movable in one direction from a neutral low beam position to a latched high beam position and in another direction from the neutral position to anon-latched high flash position;

the method comprising;

monitoring the states of the headlamps when the headlamp on/off switch is in its automatic position;

causing the controller to change from the automatic mode to an override mode if the high beam state is detected and the high/low beam switch is detected as moved from the neutral position to the non-latched position whereupon the controller changes the headlamps to the low state when the high/low beam switch is subsequently released to the neutral position;

causing the controller to temporarily change from the automatic mode to the override mode if the low beam state is detected and the high/low beam switch is detected as moved from the neutral position to the non-latched position whereupon the controller changes the headlamps to the high state temporarily while the high/low beam switch is in the non-latched position and thereafter changes the headlamps back to the low state when the high/low beam switch is subsequently released to the neutral position, the controller changing back from the override mode to the automatic mode with the changing of the headlamps back to the low state.

2. A method as claimed in claim 1 wherein the automatic mode of the system is resumed, after the controller changes to the override mode, when the controller has monitored that the high/low beam switch has been moved sequentially to the latched position and then to the neutral position.

3. A method as claimed in claim 1 in which the high/low beam switch is a stalk switch mounted on a steering column.

4. A method as claimed in claim 3 in which the headlamp on/off switch is integrated into the stalk switch.

5. A method as claimed in claim 4 in which the headlamp on/off switch is a rotatable switch disposed on the stalk switch.

6. A method as claimed in claim 1 in which the headlamp on/off switch also includes a selectable Off position and an exit delay position, wherein, when the exit delay position is selected, the controller operates the system in the automatic mode.

7. A method as claimed in claim 1, the vehicle having an instrument cluster including a display which is coupled to the controller by a standard network bus and to a user interface, the controller, when the headlamp switch is detected as being in the automatic position, being also arranged to turn on or off the headlamp as a function of the sensed ambient light, in which the control of the headlamp states as a function of the sensed intensity of the light source by the controller can be disabled through the user interface.

8. A method as claimed in claim 7, in which the forward-facing sensor is capable of being adjusted to the side of the road the vehicle is moving via selection of the left or right side from the instrument cluster via the user interface.

9. A method as claimed in claim 2 wherein the controller remains in the override mode, after changing to the override mode in claim 1, when the controller has monitored that the high/low beam switch has been moved sequentially to the non-latched position and then released to the neutral position.

10. A method as claim in claim 9 wherein the controller changes the headlamps from the low state to the high stage for at least a portion of a period taken to move the high/low beam switch between the neutral and non-latched positions of claim 9.

11. A method as claimed in claim 2 wherein the controller changes the headlamps from the low state to the high state for at least a portion of a period taken to move the high/low beam switch between the neutral and latched positions.

12. A controller switching between manual and automatic control of a vehicle headlamp between at least a first and second state of illumination comprising:

the controller transitioning from automatic control to manual control when (1) the switch is moved from a first position to a second position while the headlamp is in the second state;

(2) when the switch is moved from the first position to a third position while the headlamp is in the first state; and

(3) when the switch is moved from the first position to the third position while the headlamp is in the second state;

the controller continuing to operate according to the manual control when transitioned due to (1), (2), or (3) until the switch is moved from the first position to the third position and then back to the first position whereupon the controller returns to operate according to the automatic control; and

the controller temporarily transitioning from the automatic control to the manual control in so far as the controller temporarily overrides the automatic control dictating control of the headlamp to be in the first state to instead be in the second state for a temporary period of time corresponding with the switch being retained in the second position whereupon the controller immediately transitions back to the automatic control once the switch returns to the first position.

13. The controller of claim 12 wherein the switch must be moved to the first position before the switch can be moved to either one of the second and third positions.

14. The controller of claim 12 wherein the headlamp is switched from a current state of being in either the first state and the state when the transition from the automatic control to the manual control results from (1) and (2) but not (3).

16. The method of claim 12 further comprising the controller, while operating within the third state, changing the headlamp to be in the high state whenever the switch is moved from the neutral position to the non-latched position while the headlamp is in the low state, and thereafter, changing the headlamp to be in the low state as soon as the switch is no longer retained in the non-latched position.

17. The method of claim 13 further comprising the controller, while operating within the third state, in the following sequential order, changing the headlamp to be in the high state whenever the switch is moved from the neutral position to the latched position while the headlamp is in the low state, and thereafter, transitioning to operate according to the first state when the switch is moved back from the latched position to the neutral position.

18. The method of claim 12 further comprising the controller controlling the headlamp to be in the high state during the second operating state only for a period corresponding with retention of the switch in the non-latched position.

15. A method of switching between manual and automatic control of a vehicle headlamp, wherein the manual control is characterized by a controller relying on user inputs to switch the headlamp between high and low states and the automatic control is characterized by the controller relying on sensed inputs to switch the headlamp between the high and low states, wherein the controller detects the user inputs from movements of a switch between a neutral position and either one of a latched position and a non-latched position, the latch position characterized by the switch remaining in the latched position in the absence of user force moving the switch back from the latched position to the neutral portion, the non-latched position characterized by the switch remaining in the latched position as long as user force retains the switch in the non-latched position against force applied by an element that otherwise forces return of the switch to the neutral position, the method comprising:

operating the controller in a first state, the first state characterized as the controller according to the automatic control to control the headlamp to be in one of the high state or the low state depending on the sensed inputs;

while operating in the first state with the headlamp in the low state, the controller transitioning to operate in a second state upon movement of the switch from the neutral position to the non-latched position, the second state characterized as a temporarily override of the automatic control in that the headlamp is changed from the low state to the high state while the automatic mode dictates controlling the headlamp to be in the low state;

while operating in the second state, the controller returning back to operate in the first state upon movement of the switch back to the neutral position from the non-latched position of the second state, the return characterized as the controller ceasing to override the automatic mode and the controller returning the headlamp to the low or high state dictated by the automatic mode;

while operating in the first state, the controller transitioning to operate in a third state when (1) the switch is moved from the neutral position to the non-latched position while the headlamp is in the high state and (2) when the switch is moved from the neutral position to the latched position while the headlamp is in either one of the high state and the low state, the third state characterized as the controller changing from the automatic control to the manual control;

while operating in the third state, the controller transitioning to operate in the first state when, in the case of (1), the switch is moved from the neutral position to the latched position and then back to the neutral position, and when, in the case of (2), the switch is moved from the latched position to the neutral position.