JP2506005B2 - Illumination angle adjustment device for vehicle headlights - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a vehicle front suitable for use in remotely adjusting the irradiation angle of a headlight held in a tiltable manner with respect to a vehicle body from a driver's seat side by remote control. The present invention relates to an irradiation angle adjustment device for a lamp.

[0002]

2. Description of the Related Art In a vehicle, especially an automobile, a large load is applied to a front wheel side or a rear wheel side of a vehicle body because a vehicle body and an axle are connected by a suspension device composed of a leaf spring, a coil spring or the like. The attitude of the vehicle will be in the state of sinking or sinking forward, and the irradiation angle of the headlight in the vertical direction with respect to the road surface will change, which impairs driving safety, and the headlight will be turned upward by sinking in the rear. If this happens, there is a danger that the driver of the oncoming vehicle will be significantly dazzled. In order to correct such a change in the irradiation angle of the headlight with respect to the road surface, the headlight is held tiltably with respect to the vehicle body, and the irradiation angle of the headlight is remotely controlled from the driver side. There have been proposed various devices configured so as to be adjustable. For example, as an example thereof, a divided voltage of different value is taken out through a signal line by switching the connection position with respect to a set voltage taking out resistor, and the taken out divided voltage (set voltage) is taken out from a reference resistor. There is proposed an irradiation angle adjusting device for a vehicle headlamp that generates an output signal by comparing it with the reference voltage and changes the irradiation angle of the headlight to a position determined according to the generated output signal.

[0003]

However, in the above-mentioned irradiation angle adjusting device, the output side terminal of the signal line is connected to the power supply voltage through the resistor, and the signal line for extracting the set voltage is disconnected. When short-circuited with the ground side,
The set voltage becomes the minimum set voltage and is compared with a plurality of reference voltages. Therefore, an output signal corresponding to the minimum set voltage is generated, and the irradiation direction of the headlight is changed to a position determined according to the generated output signal. In addition, when the signal line for extracting the set voltage is disconnected and opened, the set voltage becomes equal to or higher than the maximum set voltage and is compared with the plurality of reference voltages. In this case, an output signal according to the maximum set voltage is generated, and the irradiation direction of the headlight is changed to a position determined according to the generated output signal. That is, when the variable operation of the irradiation direction is set to 5 steps, if the signal line is disconnected and shorts to the ground side, the irradiation direction moves to the lowest position (5 step position). Also,
When the signal line is broken and opened, the irradiation direction moves to the uppermost position (position 0). When the signal line is short-circuited and the irradiation direction moves to the lowermost position, if the vehicle body is normally tilted, the irradiation direction becomes too downward and front visibility deteriorates. When the signal line is in the open state and the irradiation direction moves to the uppermost position, if the vehicle body is normally tilted, the irradiation direction will be too upward and the oncoming vehicle will be dazzled. Further, if the short and open of the signal line is repeated halfway, the irradiation direction may rise or fall during traveling, which is not preferable for safe traveling.

[0004]

The present invention has been made to solve such a problem, and in the irradiation angle adjusting apparatus described above, the set voltage obtained via the signal line is out of the predetermined voltage range. In that case, the output signal as a predetermined signal,
This is to prohibit the variable operation of the irradiation angle.

[0005]

According to the present invention, therefore, when the signal line is broken and short-circuited by appropriately setting the predetermined voltage range, the set voltage is determined to be outside (lower than) the predetermined voltage range and the output signal is set to the predetermined signal. , It is possible to prohibit the variable operation of the irradiation angle. Further, when the signal line is broken and is in an open state, it is possible to prohibit the variable operation of the irradiation angle by setting the output signal as a predetermined signal assuming that the set voltage is outside (exceeding) the predetermined voltage range.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The irradiation angle adjusting device for a vehicle headlamp according to the present invention will be described in detail below.

FIG. 2 is a circuit diagram showing an embodiment of this irradiation angle adjusting device. In the figure, 4 is a set voltage extracting circuit arranged on the driver's seat side, and 5 is a drive unit attached to a headlight (not shown) held so as to be tiltable with respect to the vehicle body.

The set voltage extracting circuit 4 is composed of a set voltage extracting resistor 41 formed by connecting resistors R1 to R5 in series, and a rotary operation switch 42. Then, one end of the resistor R1 (one end of the set voltage extracting resistor 41),
Connection point between resistors R1 and R2, connection point between resistors R2 and R3,
The connection point between the resistors R3 and R4 and the connection point between the resistors R4 and R5 are the switching terminals 42-1, 42-2, 42- of the operation switch 42.
3, 42-4, 42-5, respectively, and the common terminal 42-0 of the operation switch 42 is connected to the signal / power common terminal 5a of the drive unit 5 through the output line 4a and the signal line L. . One end of the set voltage extracting resistor 41 is open and the other end (the other end of the resistor R5) is grounded (body ground).

That is, by switching the connection position of the operation switch 42 with respect to the set voltage extracting resistor 41 whose one end is open and the other end is grounded, the divided voltage of different value is driven as the set voltage as described later. It occurs at the signal / power shared terminal 5a of the unit 5. In addition,
The set voltage extracting resistor 41 may have a configuration as shown in FIG.

On the other hand, the drive unit 5 is a hybrid I
C (hereinafter abbreviated as HIC) 51, irradiation angle variable circuit 5
2, a diode D1, a resistor R6, a capacitor C1 and a zener diode ZD. Drive unit 5
, The signal / power sharing terminal 5a is connected to the HIC51.
Is connected to the terminal 51-1. Terminal 51 of HIC51
The power supply voltage defined by the Zener diode ZD is applied to -2, and the voltage from the vehicle-mounted battery 3 is directly applied to the terminal 51-3 via the diode D1. The terminal 51-4 of the HIC 51 is grounded (body ground), and the output signals generated at the terminals 51-5 to 51-9 are supplied to the irradiation angle variable circuit 52.

The irradiation angle variable circuit 52 is a sliding contact structure 52.
-1, a relay circuit section 52-2, a motor 52-3 and a PTC. The relay circuit section 52-2 includes relays RY1 and R
And Y2, and the connections as shown in the drawing are made.

Next, the operation of the irradiation angle adjusting device constructed as described above will be described. Now, assuming that the operation switch 42 is in the connection mode 0 state, that is, the common terminal 42-0 and the switching terminal 42-1 are connected, the HIC 51 outputs an "L" level signal only to the terminal 51-5. Is output. From this state, the operation switch 42
When the connection mode is changed to, for example, the connection mode I, a divided voltage having a value different from that before is generated in the signal / power common terminal 5a as the set voltage. This allows
The HIC 51 sets the terminal position for outputting the “L” level to 51
Move from -5 to 51-6.

Then, the diode D1-relay coil R
Current flows through the path of y1-sliding contact structure 52-1-terminal 51-6, the common terminal ry1c of the relay coil Ry1 and the normally-open contact terminal ry1a become conductive, and the motor 52-3 moves in the direction A in the figure. An electric current flows. Thereby, the motor 52
-3 rotates in the forward direction to move the irradiation direction of the headlight downward, changes the contact connection state in the sliding contact structure 52-1 and releases the energization bias of the relay coil Ry1. Then, the common terminal ry1c of the relay coil Ry1 and the normally open contact terminal ry
The power supply to the motor 52-3 is cut off, and the headlamp is fixed at a predetermined position (the I-stage position) in the downward direction.

In the same manner, if the connection mode of the operation switch 42 is changed to II, III, IV, the divided voltage having different values will be generated as the set voltage at the signal / power supply common terminal 5a one after another. The terminal position for outputting the "L" level moves to 51-7, 51-8, 51-9, and the irradiation direction of the headlamp is fixed at the II, III, and IV stage positions in the downward direction. Become.

On the other hand, if the connection mode of the operation switch 42 is set to III while the irradiation direction of the headlight is fixed to the IV stage position, the terminal position for outputting the "L" level is 51-8. Move and diode D1-relay coil R
A current flows through the path of y2-sliding contact structure 52-1 -terminal 51-9, the common terminal ry2c of the relay coil Ry2 and the normally open contact terminal ry2a become conductive, and the motor 52-3 moves in the direction B in the drawing. An electric current flows. As a result, the motor 52-3 rotates in the reverse direction to move the irradiation direction of the headlamp upward, change the contact connection state in the sliding contact structure 52-1 and release the energization of the relay coil Ry2. Then, the common terminal ry2c of the relay coil Ry2 and the normally open contact terminal ry2a become non-conductive, and the power supply to the motor 52-3 is cut off.
The irradiation direction of the headlight will be fixed at a predetermined position in the upward direction (stage III position).

FIG. 1 shows a specific internal structure of the HIC 51, in which a terminal 51-1 is connected to a terminal 51-2 via a resistor R7. That is, the power supply voltage is applied to the set voltage extracting resistor 41 via the resistor R7, and different values are generated at the connection point between the resistor R7 and the setting voltage extracting resistor 41 depending on the connection mode of the operation switch 42. The divided voltage is applied to the non-inverting input terminals of the comparators CPa-1 to CPa-6 in the voltage comparison circuit 512 as the set voltage V _IN . Then, the divided voltages V1 to V6 generated at the connection points of the resistors R9 to R15 of the reference voltage setting resistor 511 are applied to the inverting input terminals of the comparators CPa-1 to CPa-6 as reference voltages. Then, the outputs of the comparators CPa-1 to CPa-6 in the voltage comparison circuit 512 are output as signals (f) to
(A) and the signals (f) to (b) are output signal generation circuit 5
It is applied to the inverting input terminals of the comparators CPb-1 to CPb-5 in No. 13. Comparator CPb-1 to CPb-
The reference voltage V4 is applied to the non-inverting input terminal of 5,
The outputs of the comparators CPb-1 to CPb-5 are signals (h) to
(L) is given to the inverters INV-1 to INV-5 in the transistor array 513-1. The outputs of the inverters INV-1 to INV-5 are the terminals 5
It is connected to 1-5 to 51-9.

Table 1 is a truth table showing the level changes of the signals (a) to (l) with respect to each connection mode of the operation switch 42 in the irradiation angle adjusting apparatus constructed as described above.

[0018]

As is clear from the truth table, by appropriately changing the connection mode of the operation switch 42, the "H" level position of the signals (h) to (l) changes according to the connection mode, The irradiation angle of the headlight is variable via the sliding contact structure 52-1 at a position determined according to the "H" level position of the signals (h) to (l).

Now, assume that the signal line L is disconnected and short-circuited with the ground side. In this case, the set voltage generated at the signal / power supply shared terminal 5a, that is, the set voltage generated at the terminal 51-1 of the HIC 51 is equal to or lower than the reference voltage applied to its inverting input terminal in the comparator CPa-6,
That is, the set voltage is out of the predetermined voltage range, and the signals (a) to (f) are all at the “L” level. Therefore, the signals (h) to (l) are all at the “L” level, the terminals 51-9 to 51-5 are all at the “H” level, and the signal line L is short-circuited in the headlamp irradiation direction. Maintain the previous state. That is, according to this embodiment, even if the signal line L is short-circuited, the irradiation angle variable operation is not performed.

Further, assume that the signal line L is disconnected and is in an open state. In this case, the set voltage generated at the signal / power supply shared terminal 5a, that is, the set voltage generated at the terminal 51-1 of the HIC 51 is larger than the set voltage obtained when the connection mode of the operation switch 42 is set to 0.
Therefore, in the comparator CPa-1, the set voltage applied to the non-inverting input terminal becomes equal to or higher than the reference voltage applied to the inverting input terminal, that is, the set voltage is out of the predetermined voltage range, and the signals (a) to (( All of f) become "H" level. Therefore, the signals (h) to (l) are all at the “L” level, the terminals 51-9 to 51-5 are all at the “H” level, and the signal line L is in the open state in the headlamp irradiation direction. The state just before is maintained. That is,
According to this embodiment, even if the signal line L is opened, the irradiation angle is not changed.

Signal (a) when signal line L is broken
Table 2 shows the level change of (l).

[0023]

In the above-described embodiment, the illumination angle of the headlight is adjusted by manually operating the operation switch 42 in the set voltage extraction circuit 4, but, for example, a sensor from a tilt angle sensor is used. The connection mode of the operation switch 42 may be automatically switched in response to a signal to adjust the irradiation angle of the headlight.

Further, in the embodiment, the irradiation angle of the headlight in the vertical direction is adjusted, but it is also possible to apply it to the adjustment of the irradiation angle of the headlight in the horizontal direction. Needless to say.

[0026]

As is apparent from the above description, according to the present invention, by appropriately setting the predetermined voltage range,
When the signal line is broken (shorted / opened), the output voltage becomes a predetermined signal assuming that the set voltage is out of the predetermined voltage range, and the variable operation of the irradiation angle can be prohibited.
Even if the short and open are repeated, the irradiation direction does not rise or fall, and many excellent effects are achieved.

[Brief description of drawings]

FIG. 1 is a diagram showing a specific internal configuration of a hybrid IC in the irradiation angle adjusting device shown in FIG.

FIG. 2 is a circuit configuration diagram showing an embodiment of an irradiation angle adjusting device for a vehicle headlamp according to the present invention.

FIG. 3 is a diagram showing another configuration example of a set voltage extracting resistor in this irradiation angle adjusting device.

[Explanation of symbols]

 4 Set voltage extraction circuit 41 Set voltage extraction resistance 42 Operation switch 5 Driving unit 51 HIC 52 Irradiation angle variable circuit 511 Reference voltage setting resistor 512 Voltage comparison circuit 513 Output signal generation circuit R7 Resistance L signal line

Claims (1)

(57) [Claims] 1. A divided voltage having different values is taken out as a set voltage through a signal line by switching the connection position of the resistance means, and the taken set voltage is compared with a plurality of reference voltages to output an output signal. In the irradiation angle adjusting device for a vehicle headlamp, which generates, and changes the irradiation angle of the headlight in the vehicle at a position determined according to the generated output signal, a set voltage obtained via the signal line is predetermined. An irradiation angle adjusting device for a vehicle headlamp, comprising: a fail-safe means for prohibiting the variable operation of the irradiation angle when the output signal is out of the voltage range.