JP2011162153A - Auto-leveling system for vehicle lamp - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an auto-leveling system for a head lamp which can properly illuminate a forward place of an automobile and thus can ensure driver's forward visibility even when the axis of irradiating light of the head lamp is sufficiently directed downward upon rapid deceleration of the automobile. <P>SOLUTION: The auto-leveling system for the head lamp includes an irradiation control means which deflects vertically the irradiation direction of the head lamp depending upon the posture of the vehicle. The irradiation control means deflects the irradiation direction of the head lamp upward by a predetermined angle when the deceleration of the vehicle is not less than the predetermined threshold, so that the driver's forward distant visibility is ensured. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

The present invention relates to an auto leveling system for a vehicular lamp that deflects the irradiation direction of a vehicular lamp that illuminates the front of a vehicle such as an automobile in the vertical direction according to the pitch angle of the vehicle.

Due to the change in the vertical inclination angle (hereinafter referred to as the pitch angle) of the front part of the vehicle body when the automobile is stopped or running, the irradiation optical axis with respect to the road surface of the headlamp is also changed vertically. When the irradiation optical axis is upward, other vehicles such as a preceding vehicle and an oncoming vehicle are dazzled. When the irradiation optical axis is downward, the frontal illumination is insufficient and the driver's distant visibility decreases. To solve this problem, the headlamp's irradiation optical axis can be controlled to change up and down with respect to the vehicle body, and the change in the vehicle body pitch angle relative to the reference pitch angle is detected. There has been proposed an auto leveling system in which control is performed so that the change of the angle is canceled and the irradiation optical axis of the headlamp with respect to the road surface coincides with a predetermined aiming angle. In such an automatic leveling system, if the change in the pitch angle is directly applied to the change control of the irradiation optical axis, the irradiation optical axis is changed even by a slight change in the pitch angle during traveling. You may feel it.

Therefore, in Patent Document 1, a moving average value for a certain period of time is calculated for the pitch angle, and the irradiation optical axis is controlled based on the moving average value. A technique that eliminates the problem has been proposed.

JP 2001-171425 A

Since the technique of Patent Document 1 performs filtering for dulling the change of the irradiation optical axis following the change of the pitch angle, for example, the automobile 1 that irradiates a predetermined low beam light distribution LP as shown in FIG. When the vehicle body of the automobile 1 is temporarily downward significantly, such as when the driver suddenly brakes suddenly while driving at a constant speed, the moving average value is calculated. As a result, the irradiation optical axis of the lamp 6 is not subject to follow-up control regardless of the change in the pitch angle of the vehicle body. Therefore, the state in which the irradiation optical axis X of the lamp 6 is directed downward follows the vehicle body downward, and the irradiation target position S cannot be irradiated, and the driver's forward visibility is reduced.

The present invention has been made in view of the circumstances as described above, and an object thereof is to provide an auto leveling system for a vehicle lamp that prevents a control delay due to calculation of a moving average when suddenly decelerating from during high-speed cruise traveling. To do.

The present invention provides a headlamp auto-leveling system comprising irradiation control means for deflecting the irradiation direction of the headlamp in the vertical direction according to the vehicle posture, wherein the irradiation control means is configured to perform the above-mentioned when the vehicle deceleration exceeds a predetermined threshold. The irradiation direction of the headlamp is deflected upward by a predetermined angle.

According to the present invention, when the deceleration of the vehicle is equal to or greater than a predetermined threshold due to an instantaneous braking operation when the vehicle is traveling at high speed, the driver is deflected by a predetermined angle upward in the headlamp irradiation direction. Ensuring frontal distant visibility.

It is a block diagram which shows the circuit structure of the auto leveling system of this invention. It is a block diagram which shows the circuit structure of an irradiation control means. It is a flowchart of the auto leveling system of this invention. It is a schematic diagram of the irradiation area | region at the time of the rapid deceleration by this invention. It is a control map at the time of deceleration in another Example of this invention. It is a schematic diagram of the irradiation area | region at the time of the rapid deceleration by a prior art.

  In the present invention, in an auto leveling system for a headlamp that includes an irradiation control means for deflecting the irradiation direction of the headlamp in the vertical direction in accordance with the vehicle posture, the irradiation control means is configured such that when the deceleration of the vehicle exceeds a predetermined threshold value. The head lamp irradiation direction is deflected upward by a predetermined angle.

  Next, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a conceptual diagram showing a block configuration of a system in which the present invention is applied to an auto leveling system for an automobile lamp. In FIG. 1, lamps 6L and 6R are respectively provided on the left and right of the front portion of the automobile 1, and these lamps 6L and 6R respectively have a low beam lamp unit 7 that irradiates a predetermined low beam in the straight direction of the automobile 1. I have. Although details are omitted, the irradiation direction of the low beam lamp unit 7 can be changed in the vertical direction by the leveling actuator 5.

In FIG. 1, the vehicle 1 is provided with a vehicle height sensor 2, and the vehicle height sensor 2 detects the height of the front wheel portion of the vehicle of the vehicle 1, in other words, the height from the road surface. Is possible. The vehicle height sensor 2 is connected to an ECU (Electronic Control Unit) 4 which is an irradiation control means capable of performing a required calculation and control. The vehicle 1 is provided with a vehicle speed sensor 3 for detecting its own vehicle speed, and this vehicle speed sensor 3 is also connected to the ECU 4. Further, the control end of the ECU 4 is connected to the leveling actuator 5 of the lamp, and the ECU 4 can control the leveling actuator 5 to control the irradiation optical axis of the lamp in the vertical direction as described above. Has been.

FIG. 2 is a conceptual diagram showing a block configuration of a system of the ECU 4 that is an irradiation control means. The ECU 4 calculates the pitch angle of the vehicle 1 of the vehicle 1 from the vehicle height detected by the front vehicle height sensor 2 and the vehicle speed for calculating the vehicle speed based on the vehicle speed signal detected by the vehicle speed sensor 3. A calculation unit 41 and an acceleration calculation unit 42 that calculates the acceleration of the vehicle based on the temporal change of the calculated vehicle speed are provided. The calculated pitch angle, vehicle speed, and acceleration are each input to the control unit 43. An actuator driving unit 45 for controlling the leveling actuator 5 based on a control signal calculated by the control unit 43 from the pitch angle, the vehicle speed, and the acceleration to control the irradiation optical axis of the low beam lamp unit 7 in the vertical direction; It has.

The control unit 43 has a function of comparing the acceleration input from the acceleration calculation unit 42 with a predetermined threshold value set in advance, a function of calculating a moving average value for a certain time with respect to the pitch angle, and the moving average value based on the moving average value. It has a function to calculate the control signal (normal leveling control) and data of a predetermined angle α for offsetting the irradiation optical axis. Based on the comparison result of acceleration, the calculation with the required algorithm as will be described later To determine the attitude and running state of the vehicle, and control the leveling actuator 5 to output a control signal for controlling the irradiation optical axis of the low beam lamp unit 7 in the vertical direction to the actuator driving unit 45.

The leveling control of the irradiation optical axis of the headlamp in the auto leveling system having the above configuration will be described with reference to the flowchart of FIG. When an ignition switch or the like of an automobile whose description is omitted is turned on, the flow starts, a vehicle speed signal from the vehicle speed sensor 3 is input to the ECU 4, and the ECU 4 calculates the vehicle speed in the vehicle speed calculation unit 41 (S1), and further obtained. The acceleration calculation unit 42 calculates acceleration (deceleration) from the change of the vehicle speed on the time axis (S2). These vehicle speed and acceleration are input to the control unit 43, and the control unit 43 determines whether the deceleration is equal to or greater than a predetermined threshold (S3). When it is determined that the deceleration is not equal to or greater than the predetermined threshold, the control unit 43 calculates a moving average value for a certain period of time for the pitch angle input from the pitch angle calculating unit 44, and controls the irradiation optical axis based on the moving average value. The normal leveling control to be performed is executed (S5).

On the other hand, when it is determined that the deceleration is equal to or greater than the predetermined threshold, the control unit 43 offsets the irradiation optical axis X of the low beam lamp unit 7 by a predetermined angle α so as to deflect upward (S4). As a result, even if the front part of the vehicle body sinks greatly downward due to an instantaneous braking operation when the vehicle is traveling at high speed, the irradiation optical axis X of the low beam lamp unit 7 is deflected upward by a predetermined angle α. Therefore, it is possible to irradiate the irradiation target position S with a predetermined low beam light distribution LP as shown in FIG. At this time, since the control unit 43 uses a predetermined angle α, there is no need to perform an operation such as calculating a moving average value of the pitch angle, and the irradiation optical axis can be quickly deflected upward. it can.

As another example, the predetermined angle α can be deflected according to the situation during deceleration. FIG. 5 is a deceleration control map in which a predetermined angle α is set according to the vehicle speed and deceleration before deceleration, and is stored in the control unit 43. After determining that the deceleration is equal to or greater than a predetermined threshold, the control unit 43 reads a predetermined angle α on the deceleration control map from the vehicle speed and the deceleration, and the irradiation optical axis of the low beam lamp unit 7 by the read predetermined angle α. Is deflected upward.

Since the control unit 43 uses the control map during deceleration, it is not necessary to calculate the moving average value of the pitch angle, etc., and the irradiation optical axis is quickly deflected for rapid deceleration to ensure visibility. Can do. Further, when the deceleration is small and the vehicle inclination is small, the leveling offset amount is reduced to secure the optimum leveling position, so that the leveling offset amount becomes excessive and there is no possibility of giving glare to the oncoming vehicle or the like. Furthermore, when the deceleration is large and the vehicle has a large inclination, the leveling offset amount is increased to secure the optimum leveling position, so that the leveling offset amount is insufficient and there is no possibility that the driver's front distance visibility will deteriorate.

As mentioned above, although the automatic leveling system of the lamp | ramp for vehicles of this invention was demonstrated along the Example, this invention is not limited to these Examples, Various change, improvement, a combination, a utilization form, etc. can be considered. Needless to say.

1: Automobile 2: Vehicle height sensor 3: Vehicle speed sensor 4: Irradiation control means (ECU)
5: Leveling actuators 6L, 6R: Lamp 7: Low beam lamp unit LP: Low beam light distribution X: Irradiation optical axis S: Irradiation target position

Claims (1)

  In an auto leveling system for a headlamp that includes an irradiation control means for deflecting the irradiation direction of the headlamp in the vertical direction according to the vehicle posture, the irradiation control means is arranged so that the deceleration direction of the vehicle is equal to or greater than a predetermined threshold value. A headlamp auto-leveling system characterized by deflecting the lamp upward by a predetermined angle.

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