JPH0471732B2 - - Google Patents

Abstract

PURPOSE:To always obtain the proper sensitivity of illuminating direction variable operation by narrowing the prevention range of the illuminating direction variable operation for a lighting means along the improvement of the judgement accuracy of a straight forward steering position in the constitution wherein the illuminating direction of the lighting means is varied interlocked with handle steering. CONSTITUTION:In the constitution wherein the illuminating direction of a lighting means such as a head lamp is made variable interlocked with handle steering, the illuminating direction variable operation of the head lamp is prevented when a steering angle is zero, or within a range W equal to or smaller than the predetermined right and left steering angles from the straight forward steering position of a handle. In this case, the predetermined steering angle range (i.e., illuminating direction variable operation prevention range) W is narrowed in sequence as shown by W1, W2 and W3 where W1>W2>W3, along the improvement of the judgement accuracy of a straight forward steering position. Furthermore, when a steering angle is outside the aforesaid steering angle ranges W1 to W3, the illuminating direction is linearly varied, interlocked with the handle steering.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a cornering lamp system for a vehicle that changes the irradiation direction of a lighting means in conjunction with steering wheel steering.

[Conventional technology]

Vehicles, especially automobiles, are equipped with headlights to illuminate the road ahead at night, but these headlights illuminate only the front of the vehicle, and when approaching a curve. In such a case, the direction in which the vehicle is traveling cannot be sufficiently illuminated. In other words, when cornering or the like, the vehicle is not sufficiently illuminated in the direction in which the vehicle is actually traveling, which may pose a danger.

In order to solve this problem, cornering lamp systems have recently been proposed in which the direction of illumination of the headlights is varied in conjunction with the steering of the vehicle's steering wheel so that the direction of travel is illuminated.

In this type of cornering lamp system, in order to obtain variable irradiation direction operation, a plurality of slits are generally formed at equal angular intervals (predetermined angular pitch) on a rotating disk that rotates in conjunction with steering wheel operation. Two photo interrupters are placed adjacent to each other at the slit passage position. In other words, the first and second
A pulsed electrical signal (two-phase incremental signal) with the same waveform but approximately 90 degrees out of phase is generated in the photo interrupter of the motor, and the steering direction and angle are detected by counting this incremental signal. .

Normally, it is impossible to detect the home position using only the two-phase incremental signals mentioned above. Therefore, in order to detect the home position, a home slit is provided on the rotating disk, and by passing this home slit to the third photo interrupter, the home position is detected. A 3-bit configuration is used to obtain signals, and a method is adopted in which the relative position of the rotating disk from the origin position is detected using incremental signals.

However, considering misalignment of the serrations between the steering shaft and the steering wheel, mounting tolerances between the steering shaft and steering sensor, poor adjustment of the wheel alignment, etc., the assembly error can reach several tens of degrees in the worst case. For this reason, usually
In order to obtain the origin signal, the angular width of the origin slit provided on the rotating disc is expanded, and even if there is an assembly error of several tens of degrees, the origin signal can be obtained as long as the vehicle is traveling straight. We believe that it is possible.

As a result, a problem arises in that the origin position, that is, the straight steering position, cannot be specified only by the presence or absence of the origin signal.In order to solve this problem, the rotation angle range (origin zone) in which the origin signal occurs Attempts have been made to divide the steering wheel into a plurality of subzones and to sequentially determine one subzone as the straight-ahead steering position based on the degree of contribution to the generation of the origin signal from among the subzones. That is, if such a method for determining the straight-ahead steering position is adopted, the accuracy of determining the straight-ahead steering position improves as the driving condition becomes stable based on actual steering wheel steering.

[Problem to be solved by the invention]

However, in conventional cornering lamp systems, if the steering wheel is turned even slightly from the forward steering position, the direction of illumination of the headlights is changed in conjunction with the steering wheel steering. The irradiation direction was variable even with small changes in the steering angle. That is, while driving, the irradiation direction of the headlights changes frequently, causing eye fatigue. Mental fatigue was also great. Furthermore, due to frequent changes in the irradiation direction, the life of the drive mechanism is short and may cause failure.

For this reason, the applicant's earlier filed patent application No.
In Publication No. 229872, it was proposed to prevent the variable operation of the headlight illumination direction in conjunction with steering wheel steering within a range below a predetermined steering angle starting from the straight-ahead steering position. The blocking range of the variable irradiation direction operation is kept constant over the entire vehicle speed range. In other words, since the blocking range of the variable irradiation direction operation is constant regardless of the driving condition, if the blocking range of the variable irradiation direction operation is set wide to make it less sensitive to large steering wheel turns at the start of driving, the driving speed A problem has arisen in that the necessary variable operation of the irradiation direction cannot be obtained for a relatively small steering wheel operation when the operating condition is stabilized by rising. Furthermore, when attempting to increase the sensitivity to relatively small steering wheel turns during stable driving, a problem arises in that the irradiation direction is unnecessarily varied in response to large steering wheel turnings at the start of driving. .

[Means to solve the problem]

The present invention has been made to solve these problems, and is designed to improve the accuracy of determining the straight-ahead steering position and to narrow the range in which the irradiation direction variable operation of the lighting means is inhibited.

[Operation] Therefore, according to the present invention, as the accuracy of determining the straight-ahead steering position improves, that is, as the driving condition becomes stable based on the actual steering wheel steering, the range of inhibition of the irradiation direction variable operation is narrowed. .

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS The vehicle cornering lamp system according to the present invention will be explained in detail below. FIG. 1 is a irradiation direction variable characteristic diagram showing the basic principle of this cornering lamp system. That is, in the same figure,
The vertical axis shows the lamp (headlight) deflection angle, and the horizontal axis shows the steering angle. Changes in the steering angle in the positive and negative directions starting from the zero point indicate right steering and left steering; Changes in the lamp deflection angle in the positive and negative directions starting from the starting point indicate changes in the irradiation direction of the headlight toward the right and left of the front of the vehicle starting from the front direction. In addition, the characteristics shown by the solid line are the irradiation direction variable characteristics at the start of operation, the characteristics shown by the dashed-dotted line are the irradiation direction variable characteristics when the straight steering position judgment accuracy is improved by one step, and the broken lines are the characteristics shown by the dashed line. Furthermore, the irradiation direction variable characteristics are shown when the determination accuracy is improved by one more step. As can be seen from this characteristic diagram, the range W1, W2, W3 (W1>W
2>W3), the irradiation direction variable operation is prevented, and in the range below this predetermined steering angle (irradiation direction variable operation inhibition range) W1, W2, and W3, the irradiation direction is fixed toward the front. That is,
As the accuracy of determining the straight steering position improves, the irradiation direction variable operation inhibition range is symmetrically narrowed around the determined straight steering position. Then, the irradiation direction is linearly varied in the right and left steering directions in conjunction with the right steering and left steering from the time when the irradiation direction variable operation inhibition range is removed.

Therefore, as the accuracy of determining the straight-ahead steering position improves, that is, as the driving condition becomes stable based on actual steering wheel steering, the blocking range of the irradiation direction variable operation becomes narrower and its sensitivity becomes sharper, so that it can be quickly adjusted to the driving condition. Therefore, a variable irradiation direction operation can be obtained.

FIG. 2 is a block diagram showing an embodiment of a cornering lamp system to which the above-described principle is applied. In the figure, reference numeral 5 inputs a pulsed electric signal sent out by a rotational position detection sensor (steering angle sensor) 100 (Fig. 3), and processes signals (up signal and down signal) according to steering wheel steering.
6 is this UP/DOWN switching circuit that sends out
This is a first UP/DOWN counter that receives the processed signal sent from the UP/DOWN switching circuit 5 as input.

The steering angle sensor 100 is composed of a rotating disk 1 that rotates in conjunction with steering wheel steering, and photo interrupters 2 to 4 each having a light emitting element and a light receiving element. Slits 1 of the same shape at equal angular intervals (predetermined angular pitch P)
a has been established. And this slit 1a
Photo interrupters 2 and 3 are arranged adjacent to each other at the passing positions of the photo interrupters 2 and 3, and as the rotary disk 1 rotates, the photo interrupters 2 and 3 pass through the slit 1a, as shown in FIGS. 4a and 4b. A pulsed electrical signal having the same waveform and alternating "1" level and "0" level is generated. That is, if the steering wheel is now rotated clockwise (also clockwise in FIG. 3) from the steering state shown in FIG. When rotated to , an electrical signal in the negative direction centered at point N is generated. The electrical signal generated in the photo interrupter 2 is 90 degrees ahead of the electrical signal generated in the photo interrupter 3, and is at the origin position (steering neutral position) of the rotating disk 1, which is ideal in design, that is, at the fourth position. At point N shown in the figure, the electrical signal generated in the photo interrupter 2 is in the falling or rising period when it changes from the "1" level to the "0" level or from the "0" level to the "1" level, and the photo interrupter 2 The electrical signal generated at 3 is in the "0" level state. And this photo interrupter 2 and 3
The electric signal sent out is input to the UP/DOWN switching circuit 5.

On the other hand, a slit 1b serving as an origin zone is independently provided at a predetermined rotational angle position on the outer peripheral edge surface of the rotating disk 1, and a photointerrupter 4 detects passage through the slit 1b. That is, the rotational position where the slit 1b faces the photo interrupter 4 is the origin range of the rotary disk 1, and the angular width of this origin range, that is, the angular width α of the slit 1b, is determined by the serration deviation between the steering shaft and the handlebar. The setting is set to exceed the worst-case assembly error, which takes into account installation tolerances between the steering shaft and steering sensor, poor wheel alignment, etc. In this embodiment, the angular width α of the slit 1b is set to 60°, and in the inventor's investigation, a value of 50° was experimentally obtained as the worst case of the assembly error, so the angular width α of the slit 1b is
If the angle is set to 60 degrees, the origin range detection signal (FIG. 4c) of level "1" can be obtained as the electrical signal sent by the photo interrupter 4 whenever the vehicle is traveling straight. This "1" level origin range detection signal is transmitted to one end of AND gates 7 and 8, the "A" input end of decoder 9, and
The signal is supplied to one end of an AND gate 11 via an inverter 10.

Here, the photo interrupter 4 is connected to the rotating disk 1
At the origin position which is ideal in the design of
At point N shown in the figure, the angular width α of the slit 1b
It is located in the center of the city. In addition, in this embodiment, the angular width α of the slit 1b is three times the angular pitch P of the slit 1a (3-angle pitch).
It is set slightly wider.

On the other hand, the UP/DOWN switching circuit 5 processes the input pulsed electric signal and sends out up/down signals according to the amount of right and left steering of the steering wheel. DOWN
The counter 6 is configured to up-count or down-count its count value by the number of input up signals or down signals. That is, the count value of the UP/DOWN counter 6 is basically set to ±0 based on the origin position which is ideal in the design of the rotating disk 1.
When the steering wheel is turned to the right, the count value increases sequentially at each falling edge of the output of the photo interrupter 2. Further, by turning the steering wheel to the left, the count value is sequentially decreased at each rising edge of the output of the photo interrupter 2. That is, in FIG. 4, if the handle is rotated to the right from point N, the count value in the UP/DOWN counter 6 will increase to +1 at point a, and +1 at point b.
If the rotation is made to the left from point N, the count value in the UP/DOWN counter 6 will sequentially decrease to -1 at point c and -2 at point d. The count value of the UP/DOWN counter 6 is input to digital comparators 12 and 13.
The comparison output at 2 and 13 is the OR gate 14
The signal is applied to the first input terminals of three-input AND gates 15 and 16 via . Note that the comparator 12 has a second UP/DOWN signal.
The count value in the counter 17 is set as the left movement starting point reference value, and the comparator 13 has the following values:
The count value of the third UP/DOWN counter 18 is set as the right-hand motion starting point reference value. Then, in the comparator 12, the UP/
The input count value via DOWN counter 6 is
When the count value through the UP/DOWN counter 17 becomes lower than the set count value, the comparison output becomes "1" level, and the comparator 13 outputs the
When the input count value via the UP/DOWN counter 6 exceeds the set count value via the UP/DOWN counter 18, the comparison output becomes "1".
It has become a level. Also, UP/
The DOWN counters 17 and 18 are set to -3 and +3 as their count values by supplying a load signal, which will be described later.

On the other hand, the UP signal and DOWN signal sent from the UP/DOWN switching circuit 5 are input to the second input terminals of the AND gates 15 and 16. The signal and the down signal are the fourth
The signal is input to the UP/DOWN counter 19. And this UP/DOWN counter 1
The count value at 9 is given to the D/A converter 20, and via this D/A converter 20,
A voltage value corresponding to the count value of the UP/DOWN counter 19 is set to the inverting input terminal of the comparator 21. Comparator 2
A sawtooth waveform reference voltage with a period of 20 msec is set to the non-inverting input terminal of the signal generator 1 via a sawtooth wave generator 22.

On the other hand, the clock signal sent from the reference clock generator 23 is applied to the other end of the AND gate 7, and its count-up operation based on the clock signal input through the AND gate 7 results in the following: An overflow signal (CARRY signal) of "1" level is sent from the counter 24, and this "1" level CARRY signal is sent UP/DOWN via the OR gate 25 as a reset signal.
to counter 19 and through or gate 29
It is given to the UP/DOWN counter 6. In addition, CARRY sent out by the counter 24
The signal is also given to the "CP" inputs of D flip-flops 26 and 27, and
When the “Q” output of the flip-flop 27 reaches the “1” level, “1” passes through the AND gate 28.
The level CARRY signal is input to the UP/DOWN counters 17 and 18 as their up and down signals.

On the other hand, at the other ends of AND gates 8 and 11,
The comparison output sent out by the comparator 30 is inputted, and the comparator 30 immediately sets the comparison output to the "1" level by applying a predetermined voltage to the terminal 103 at the same time as the power is turned on. The comparison output is configured to return the comparison output to the "0" level after a predetermined time delay based on the increase in the amount of charge to the capacitor C3. The output of AND gate 8 is input to the other end of OR gate 29, the output of AND gate 11 is input to the set terminal of flip-flop 31, and the "Q" output of flip-flop 31 is input to the "B" input terminal of decoder 9. It has become a given. Decoder 9
The "C" and "D" input terminals have UP/DOWN
A down signal and an up signal are input through the switching circuit 5, and the decoder 9
``0'' is input to the input terminals ``D'', ``C'', ``B'', and ``A''.
，
When a signal of "1", "1", "1" is input, the level of the output terminal 9a is set to "1", and "1",
When a signal of "0", "1", or "1" is input, the level of the output terminal 9b is set to "1". When a "1" level signal is sent from the output terminal 9a of the decoder 9, this signal is passed through an OR gate 32 to a one-shot multivibrator (hereinafter simply referred to as one-shot) 33.
The one shot signal sent by this one shot 33 is
It is applied as a load signal to the UP/DOWN counter 6, and the count value in the UP/DOWN counter 6 is set to +1 via the encoder 34 based on the output state of the decoder 9 at this time. Also, the output terminal 9 of the decoder 9
When a "1" level signal is sent from b, the count value in the UP/DOWN counter 6 is set to -1 via the encoder 34 based on the output state of the decoder 9 at this time. .

In addition, the UP signal and the DOWN signal sent out by the UP/DOWN switching circuit 5 are connected to the 3-input OR gate 3.
The "1" level signal passing through this OR gate 35 is supplied to the counter 24 as its reset signal. Further, the comparison output sent out from the comparator 30 is given to the third input terminal of the OR gate 35, and the comparison output sent out from the comparator 30 is sent to the D flip-flops 26 and 27 as a set signal. The signal is supplied to UP/DOWN counters 17 and 18 as a load signal, and further to UP/DOWN counter 19 as a reset signal. Also,
Similarly to the UP/DOWN counter 6, the count value of the UP/DOWN counter 19 is basically set to ±0 with respect to the origin position which is ideal in the design of the rotating disk 1. Further, when the count value of the UP/DOWN counter 19 is ±0, the voltage value set to the inverting input terminal of the comparator 21 via the D/A converter 20 is set to the inverting input terminal of the comparator 21 via the sawtooth wave generator 22. It is assumed to be located at the center of the vertical width of the sawtooth reference voltage set at the inverting input terminal, and therefore the control signal sent from the output terminal of the comparator 21 at this time is a periodic signal with a duty ratio of 50%. It becomes a pulse signal. Then, as the count value in the UP/DOWN counter 19 increases or decreases, the set voltage value to the inverting input terminal of the comparator 21 decreases or increases in the D/A converter 21 according to the count value that increases or decreases. I'm starting to do that. That is, the pulse width of the control signal periodically sent from the output terminal of the comparator 21 is the same as that of the UP/DOWN counter 1.
Depending on the count value at 9, it becomes wider as it goes up and becomes narrower as it goes down. A control signal sent from the output terminal of the comparator 21 (output terminal 30c of the control signal generation circuit 30) is input to the servo motor control circuit 40 via its input terminal 40a.

The servo motor control circuit 40 has an input terminal 40a.
a motor drive time calculation circuit 42 and a rotation direction determination circuit 43 which take the output of this position deviation detection circuit 41 as input, and a motor drive time calculation circuit 4
2 and the output of the rotation direction determination circuit 43 as inputs.
AND gate circuit 44 and this AND gate circuit 4
4, and a potentiometer 47 whose output voltage is varied according to the rotational angular position of the electric motor 46. The specific structure and operation of this servo motor control circuit 40 are shown in detail in Japanese Patent Application No. 1983-78533 previously filed by the applicant, so a description thereof will be omitted here. That is, by widening the pulse width of the control signal sent from the output terminal 30c of the control signal generation circuit 30, the direction of illumination of the headlight (not shown) driven by the electric motor 46 can be linearly varied in the right steering direction. do. Further, the output terminal 30 of the control signal generation circuit 30
By narrowing the pulse width of the control signal sent by c, the irradiation direction of the headlight is linearly varied in the left steering direction. Also, UP/DOWN counter 1
When the count value at 9 is ±0, the irradiation direction of the headlight is fixed to face the front.

Next, the operation of the cornering lamp system configured as described above will be explained.

In other words, if you start driving now,
Immediately after power is turned on to this device, the comparison output of the comparator 30 remains at the "1" level for a predetermined period of time. This "1" level comparison output causes counter 24, UP/DOWN counter 6,
The UP/DOWN counters 19 are each reset, and the D flip-flops 26 and 27 are set. Also, UP/DOWN counters 17 and 18
The "1" level comparison output sent out by the comparator 30 is input as a load signal to set the count value to -3 and +3. In this situation, if you turn the steering wheel from the straight-ahead steering position and start steering to the right, for example,
The count value in the UP/DOWN counter 6 increases in accordance with the amount of right steering. Then, when the count value reaches +3, the comparison output of the digital comparator 13 becomes "1" level. That is, the comparison output of this digital comparator 13 passes through the OR gate 14 and is input to the AND gate 1.
5 and 16, and from this point on, the UP signal sent out from the UP/DOWN switching circuit 5 comes to be applied to the UP/DOWN counter 19. That is, when the count value in the UP/DOWN counter 6 is +3 or more, the UP signal that is generated causes the count value in the UP/DOWN counter 19 to increase, and the inverting input terminal of the comparator 21 is set in accordance with the increased count value. voltage value decreases. Therefore, the duty ratio of the pulse signal sent from the output terminal of the comparator 21, that is, the control signal input to the servo motor control circuit 40 via the output terminal 30c of the control signal generation circuit 30 increases, and the pulse signal of the control signal increases. The width will become wider. In other words, the irradiation direction of the front irradiation changes linearly to the right steering direction in conjunction with the steering wheel steering after the count value of the UP/DOWN counter 6 reaches +3 or more.

On the other hand, if you turn the steering wheel from the straight-ahead steering position and start steering to the left, the count value in the UP/DOWN counter 6 will decrease according to the amount of left steering, and when the count value reaches -3, , the comparison output of the digital comparator 12 becomes "1" level. That is, the comparison output of this digital comparator 12 is the output of the OR gate 14.
, and is applied to one end of AND gates 15 and 16, and from this point on, the down signal sent from UP/DOWN switching circuit 5 is applied to UP/DOWN counter 19. That is,
The count value of UP/DOWN counter 6 is -
Due to the down signal that still occurs as 3 or less,
The count value in the UP/DOWN counter 19 goes down, and according to the down count value,
The voltage value set at the inverting input terminal of the comparator 21 increases. Therefore, the duty ratio of the pulse signal sent out from the output terminal of the comparator 21, that is, the control signal input to the servo motor control circuit 40 via the output terminal 30c of the control signal generation circuit 30, decreases, and the pulse signal of the control signal decreases. The width becomes narrower. In other words, the direction of illumination of the headlights changes linearly toward the left steering direction in conjunction with steering wheel steering after the count value of the UP/DOWN counter 6 becomes -3 or less.

On the other hand, if the rotating disk 1 is currently in a straight-ahead running state and is located at the ideal origin position in terms of design as shown in FIG. While the origin range detection signal at the ``level'' is being input, the time the count value in the UP/DOWN counter 6 continues to be at ±0 is much longer than the time during which it continues to be at +1 and -1. That is, while the origin range detection signal at the "1" level is input through the terminal 101, the clock signal sent from the reference clock generator 23 passes through the AND gate 7, and the counter 2
4 will be provided. When a predetermined period of time elapses with the count value of the UP/DOWN counter 6 maintaining ±0, that is, when a predetermined period of time elapses without either an UP signal or a DOWN signal being sent from the UP/DOWN switching circuit 5, the supplied clock signal Due to the count-up operation based on
A level CARRY signal is sent out, and this "1" level CARRY signal is transmitted to the OR gates 29 and 25.
to the UP/DOWN counters 6 and 19. As a result, UP/DOWN counter 6
The count value at and 19 is returned to ±0. In this case, UP/DOWN counter 6
The count values at UP/DOWN counters 6 and 19 are already ±0, and based on such operations, the count values at UP/DOWN counters 6 and 19 continue to maintain ±0 in the straight-ahead steering position.

That is, by appropriately determining the number of counts up until the input clock signal to the counter 24 overflows, the UP/DOWN counter 6
During a short time period in which the count value continues to be +1 and -1, the counting operation of the clock signal in the counter 24 is reset based on the up signal and down signal via the UP/DOWN switching circuit 5.

On the other hand, if the rotating disk 1 deviates from the ideal designed origin position due to assembly errors, the count values of the UP/DOWN counters 6 and 19 are promptly corrected. be exposed.

That is, when the rotating disk 1 is at the origin position which is ideal in design, Z1(d) shown in FIG.
When the range from point to point Z2(b) is defined as the origin zone in slit 1b, within the region from point c to point a (hereinafter this region will be referred to as the first subzone) that divides this origin zone, While the vehicle is traveling straight, the count value in the UP/DOWN counter 6 remains at ±0 for a long time. However, if the rotating disk 1 deviates from the ideal design origin position due to assembly errors, the count value on the UP/DOWN counter 6 may be +1 or -1 while driving straight. It lasts longer. That is, within the region from point a to point b (hereinafter referred to as the second subzone) that divides the origin zone, or within the region from point c to point d (hereinafter referred to as the third subzone). ), the time during which the count value in the UP/DOWN counter 6 continues to be +1 or -1 is much longer than the time during which the count value continues to be ±0 within the first subzone.

UP/DOWN counter 6 in second subzone
When the count value of 6 continues to be +1 for a long time, the count value of UP/DOWN counter 6 becomes +1.
1, that is, when the second subzone of the three subzones is detected, the counter 24 sends out a CARRY signal of level "1", which causes the UP/DOWN counter 6 and The count value at 19 is returned to ±0. That is, the second subzone is quickly determined as the origin position, the count values in UP/DOWN counters 6 and 19 are corrected, and the direction of illumination of the headlight is reliably directed toward the front at the straight-ahead steering position. becomes.

Furthermore, if the time period in which the count value of the UP/DOWN counter 6 continues to be -1 in the third subzone becomes longer, when the count value of the UP/DOWN counter 6 is -1, that is, among the three subzones, At the time when the third subzone is detected, the counter 24 sends out a CARRY signal of "1" level, which causes UP/
The count values in DOWN counters 6 and 19 are returned to ±0. That is, the third subzone is quickly determined to be the origin position, the count values in the UP/DOWN counters 6 and 19 are corrected, and the direction of illumination of the headlights is reliably directed toward the front at the straight-ahead steering position. becomes.

In a cornering lamp system that performs such basic operations, the accuracy of determining the straight-ahead steering position improves as the driving condition becomes stable based on actual steering wheel steering. That is, immediately after the power is turned on to this device at the start of operation, the comparison output sent out by the comparator 30 is at the "1" level and is given to the UP/DOWN counter 19 as its reset signal. As a result, UP/
The count value of DOWN counter 19 is ±0
As a result, the direction of illumination from the headlights is forced toward the front. At this time, UP/DOWN counter 1
The count values at 7 and 18 are -3 and +
3, and the count value in the UP/DOWN counter 6 becomes -3 or less or +3 or more as the steering wheel is turned, and the headlight illumination direction is changed to the left steering direction or right steering direction in conjunction with the steering wheel steering. It becomes variable linearly. On the other hand, the straight-ahead steering position is determined by selecting one subzone from the three subzones as the counter 24 sends the CARRY signal based on the actual steering after the vehicle starts driving. After starting operation,
When the first CARRY signal is sent from the counter 24, the count values in the UP/DOWN counters 6 and 19 are returned to ±0, and
CARRY signal passes through AND gate 28
The signal is applied to UP/DOWN counters 17 and 18, and the UP/DOWN counter 17 increments its count value, and the UP/DOWN counter 18 increments its count value. As a result, the count value in the UP/DOWN counter 17 becomes -2, and the count value in the UP/DOWN counter 1 becomes -2.
The count value at 8 is +2. That is,
After the start of operation, when the first CARRY signal is sent from the counter 24, the UP/DOWN counter 6
When the count value becomes -2 or less or +2 or more as the steering wheel is turned, the direction of illumination of the headlights changes linearly to the left steering direction or the right steering direction in conjunction with the subsequent steering wheel steering.
The irradiation direction variable operation inhibition range is narrower than that immediately after the start of operation. At this time,
The "Q" output of the D flip-flop 26 goes to the "0" level based on the CARRY signal applied as its "CP" input.

Furthermore, when the second CARRY signal is sent from the counter 24 based on the steering wheel after the start of driving, the count values in the UP/DOWN counters 6 and 19 are returned to ±0 in the same manner as described above. The CARRY signal is AND gate 28
through UP/DOWN counters 17 and 18
UP/DOWN counter 17 increments the count value, and UP/DOWN counter 18 increments the count value. As a result, the count value in the UP/DOWN counter 17 becomes -1, and the count value in the UP/DOWN counter 1 becomes -1.
The count value at 8 becomes +1. That is,
After the start of operation, the second CARRY signal is sent to counter 2.
4, when the count value in the UP/DOWN counter 6 becomes -1 or less or +1 or more as the steering wheel is turned, the headlight illumination direction changes to the left steering direction or to the right. The irradiation direction can be varied linearly in the steering direction, and the range in which the irradiation direction is inhibited is further narrowed. At this time, the D flip-flop 27
The "Q" output of the D flip-flop 26 takes in the "Q" output of the D flip-flop 26 based on the CARRY signal applied as its "CP" input, and becomes the "0" level. Therefore, from now on, the ``1'' level CARRY signal sent out by the counter 24 is applied to the AND gate 2.
8, and the count values in the UP/DOWN counters 17 and 18 maintain -1 and +1, thereby maintaining the narrowed operation blocking range between irradiation directions.

Immediately after the power is turned on to this device, the comparison output sent by the comparator 30 continues for a predetermined period of time and remains at the "1" level, so that the terminal 10
When the power is turned on when the origin range detection signal of the "1" level is input through the gate 1, the comparison output of the "1" level sent out by the comparator 30 passes through the AND gate 8 and outputs the OR gate 29. Through this, the count value in the UP/DOWN counter 6 is forcibly set to ±0, and as a result, the subzone that was detected immediately after the power was turned on is set as the initial origin position.

Further, when the power is turned on when the origin range detection signal of the "1" level is not inputted via the terminal 101, a signal of the "1" level is inputted to the AND gate 11 via the inverter 10, and this The comparison output of the "1" level passing through the AND gate 11 causes the flip-flop 31 to enter the set state. As a result, the "1" level Q output of the flip-flop 31 is set to the "B" input terminal of the decoder 9. Then, as a result of subsequent steering wheel steering, the origin range detection signal at the "1" level is input via the terminal 101, this origin range detection signal at the "1" level is input to the "A" input terminal of the decoder 9. It will be set.
Now, suppose that a "1" level origin range detection signal is generated due to the clockwise rotation of the rotary disk 1 accompanying right steering, then a "1" level up signal is generated from the UP/DOWN switching circuit 5 due to this right steering. By setting to the "D" input terminal of the decoder 9, the level of the output terminal 9b of the decoder 9 becomes the "1" level at this point, and the count value in the UP/DOWN counter 6 is set to -1 in the third subzone. Then, the first subzone among the three subzones is set as the initial origin position. Furthermore, if it is assumed that the origin range detection signal of level "1" is generated due to the counterclockwise rotation of the rotary disk 1 due to left steering, then a down signal of level "1" is generated from the UP/DOWN switching circuit 5 due to this left steering. By setting to the "C" input terminal of the decoder 9, the level of the output terminal 9a of the decoder 9 becomes "1" level at this point, and the count value in the UP/DOWN counter 6 is set to +1 in the second subzone. , the first subzone among the three subzones is set as the initial origin position.

In this example, a cornering lamp system was explained in which the irradiation direction variable characteristic diagram shown in Fig. 1 was applied as the basic principle, but the irradiation direction variable characteristic diagram shown in Fig. 5 was applied as the basic principle. It may also be used as a cornering lamp system. That is, the irradiation direction variable operation inhibition area in the right steering direction may be kept constant, and the irradiation direction variable operation inhibition area in the left steering direction may be narrowed as the accuracy of determining the straight-ahead steering position improves. In addition, on the contrary, the irradiation direction variable operation blocking area in the left steering direction is kept constant, and the irradiation direction variable operation blocking area in the right steering direction is narrowed as the accuracy of determining the straight-ahead steering position improves. It may be configured as follows. Furthermore, as shown in FIG. 6, the slope of the irradiation direction variable characteristic may be changed as the irradiation direction variable operation blocking region is narrowed.

In each of the embodiments described above, the device for determining the origin position of a rotating body is configured as a hardware using a specific circuit, but it can also be implemented using a software technique using a microcomputer or the like.

〔Effect of the invention〕

As explained above, according to the vehicle cornering lamp system according to the present invention, in addition to improving the accuracy of determining the straight-ahead steering position, the range of blocking the irradiation direction variable operation of the lighting means is narrowed, so that It is possible to reduce the sensitivity to large steering wheel turns, while automatically increasing the sensitivity to relatively small steering wheel turns during stable driving.

[Brief explanation of drawings]

FIG. 1 is a variable irradiation direction characteristic diagram showing the basic principle of a vehicle cornering lamp system according to the present invention, and FIG. 2 is a block configuration diagram showing an embodiment of a cornering lamp system to which this basic principle is applied. Figure 3 is a schematic configuration diagram showing the steering angle sensor used in this system, Figure 4 is an output waveform diagram of this steering angle sensor, and Figures 5 and 6 are irradiation direction variable characteristics showing other basic principles in this system. It is a diagram. 5...UP/DOWN switching circuit, 6, 17, 18,
19...UP/DOWN counter, 12, 13...Digital comparator, 20...D/A converter,
21... Comparator, 22... Sawtooth wave generator,
23...Reference clock generator, 24...Counter, 2
6, 27...D flip-flop, 28...AND gate, 100...steering angle sensor.

Claims (1)

[Claims] 1. A cornering run lamp system for a vehicle comprising a variable irradiation direction operation blocking means for blocking a variable irradiation direction operation of a lighting means that is linked to steering wheel steering within a range of a predetermined steering angle or less starting from a straight-ahead steering position, a straight-line steering position determination means that determines the straight-line steering position while sequentially updating the position based on the steering wheel steering during driving; and an irradiation direction of the lighting means as the accuracy of determining the straight-line steering position determined by the straight-line steering position determination means improves. A vehicular cornering lamp system comprising: irradiation direction variable motion blocking range narrowing means for narrowing a variable motion blocking range.