JPS6350226B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a vehicle light control device that automatically turns on and off lights based on the traveling speed of the vehicle and the illuminance outside the vehicle.

Conventional vehicle light control devices include, for example, a first
There is something like the one shown in the figure.

In the figure, an optical sensor 1 is composed of a photoelectric element (for example, a CdS, a photoconductive cell, a photodiode), and is used to detect the illuminance outside the vehicle.

The vehicle speed sensor 2 outputs a pulse train with a frequency corresponding to the traveling speed of the vehicle, and the vehicle speed sensor 2 outputs a rotational speed corresponding to the vehicle speed transmitted via the speed cable 2a using a rotary encoder (for example, optical or electromagnetic). (induction type, etc.) and converts it into a pulse train frequency and outputs it.

The light/dark determination circuit 3 determines "dark" or "bright" depending on whether the level of the vehicle exterior illuminance signal supplied from the optical sensor 1 is equal to or higher than a predetermined threshold, and uses this determination result as " It outputs a binary signal of "1" and "0".

Further, the running/stopping determination circuit 4 determines whether the vehicle is "running" or "stopped" depending on the presence or absence of the pulse train supplied from the vehicle speed sensor 2, and divides this determination result into two of "1" and "0". It outputs a value signal.

The AND circuit 5 performs an AND operation on the judgment outputs supplied from the two judgment circuits 3 and 4, and outputs the judgment output corresponding to "dark" from the light/dark judgment circuit 3, as well as the running/stopping signal. Only when judgment outputs corresponding to "running" are simultaneously supplied from the judgment circuit 4, in other words, only when the AND condition of both judgment outputs is satisfied, the drive circuit 6 is driven to turn on the headlights. Auxiliary lights, etc. (hereinafter simply referred to as lights) 7
It lights up.

By using the above-mentioned vehicle light control device, you can prevent dazzling other vehicles when stopping at an intersection etc. when driving at night, or turn off the lights to reduce battery load. This eliminates the need for the driver to operate the light switch each time.

However, in the case of the above-mentioned vehicle light control device, since it is determined whether "running" or "stopping" is based on the presence or absence of a vehicle speed pulse train supplied from the vehicle speed sensor 2, for example, If the pulse train to the running/stopping determination circuit 4 is lost due to a failure of the vehicle speed sensor 2 or a disconnection of the speed cable 2a while driving at night, even though the vehicle is actually running, Light 7 may have been turned off by mistake.

This invention was made in view of the above problems.
The purpose of this is, for example, when it is determined whether the vehicle is running based on the output of the vehicle speed detector as in the conventional example mentioned above, and when it is determined that the outside illuminance has decreased based on the output of the vehicle exterior illuminance detector. In a vehicle light control device that turns on a light based on a light turn-on signal, the light is automatically turned off when the vehicle is stopped, but the light is maintained in a turned on state in the case of a failure of a vehicle speed detector or the like.

In order to achieve the above object, the present invention includes a deceleration rate calculation means for calculating a deceleration rate based on the output of a vehicle speed detector, and a deceleration rate calculated by the deceleration rate calculation means to a preset maximum deceleration rate. The present invention is characterized in that it is provided with an abnormal deceleration determining means for determining whether or not the abnormal deceleration exceeds the limit, and a correcting means for outputting a light lighting signal when the abnormal deceleration is determined.

FIG. 2 shows an embodiment of a vehicle light control device according to the present invention (hereinafter referred to as a first embodiment).
FIG. 2 is a block diagram showing details of a running/determination circuit of the vehicle.

The feature of this first embodiment is that the running/stopping determination circuit 4 is improved in the conventional example shown in FIG. do.

In the figure, a pulse counter 11 counts a vehicle speed pulse train output from a vehicle speed sensor 2, and receives a count start signal S from a control circuit 14.
Each time 1 arrives, a counting operation is performed for a certain period of time, and after the counting is completed, the counting data is output and held until the arrival of the next count start signal S1.

The pulse number register 12 temporarily stores the count data output from the pulse counter 11 in response to the arrival of the data read signal S2, and outputs the stored count data.

The subtraction circuit 13 subtracts the new count data output from the pulse counter 11 in response to the comparison signal output from the control circuit 14 and the old count data before updating supplied from the pulse number register 12. This calculation result is output as vehicle speed deceleration rate data.

The subtraction value discrimination circuit 15 stores previously predicted maximum deceleration rate data (for example, deceleration rate at the time of a sudden stop), and determines the deceleration rate input from the subtraction circuit 13 in response to the comparison signal S3 from the control circuit 14. The data is compared in size with the maximum deceleration rate data above, and only if the value of the input deceleration rate data is greater than the value of the maximum deceleration rate data, from that point on, it will be "running". It outputs and holds the corresponding logic signal.

The pulse presence/absence determination circuit 17 determines whether or not a pulse signal is output from the vehicle speed sensor 2 and outputs a logic signal corresponding to the determination result. Can be configured.

The control circuit 14 controls the timing of data transfer of the pulse counter 11, pulse number register 12, and subtraction circuit 13, and receives a count start signal S1, a read signal S2, and a comparison signal S, respectively.
Outputs 3.

The operation of the vehicle light control device configured as described above will be described below.

For example, when driving at night, the amount of light detected by the optical sensor 1 is small, so the light/dark determination circuit 3 outputs a logic signal "1" corresponding to "dark".

If the vehicle is in a running state in this state, the vehicle speed sensor 2 outputs a pulse train with a frequency corresponding to the vehicle speed, and the pulse presence/absence determination circuit 17 in the running/stopping determination circuit 10 indicates "pulse present", i.e. A logic signal "1" representing "running" is output.

Therefore, the AND circuit 5 includes the subtraction value discrimination circuit 1.
Regardless of the output of 5, "1" representing "dark" and "1" representing "running" are supplied at the same time, so that the AND condition is satisfied and the light 7 is automatically turned on.

In addition, if the vehicle gradually decelerates from the above-mentioned driving state to a stop state in order to make a temporary stop at an intersection, etc., the vehicle stops and the vehicle speed sensor 2
Since the vehicle speed pulse train from the vehicle disappears, the pulse presence/absence determination circuit 17 continues to output a logic signal "0" representing "no pulse", that is, "stopping", while the vehicle is stopped.

On the other hand, the vehicle speed sensor 2
As shown in Fig. 3, the pulse train output from
As the vehicle speed decreases, the period gradually becomes longer,
In other words, the frequency becomes lower.

Therefore, the value of the previous count data output from the pulse number register 12 and the pulse counter 11
The difference between the value of the current count data outputted from and the value of the maximum deceleration rate data is always smaller than the value of the maximum deceleration rate data, and therefore the subtraction value discrimination circuit 15 outputs a logic signal "0" corresponding to "normal deceleration". It happens.

Therefore, "1" representing "dark" and "0" representing "travel stop" are simultaneously supplied to the AND circuit 5, and as a result, the AND condition is not satisfied and the light 7 is automatically turned off normally. The Rukoto.

Next, in the above-mentioned night driving condition, if the pulse train output from the vehicle speed sensor 2 suddenly disappears due to a failure of the vehicle speed sensor 2, etc., the pulse presence/absence determination circuit 17 determines that there is no pulse, that is, that the vehicle is stopped. The logic signal "0" representing this result will be erroneously output.

However, the frequency change of the pulse train in the vehicle speed data at this time is as shown in Figure 3b,
The pulse signal suddenly stops appearing after the failure occurs.

For this reason, the difference between the count data before and after the occurrence of a failure becomes a significantly large value that would not be possible in a normal deceleration process, and therefore the value of the deceleration rate data output from the subtraction circuit 13 is When the value of the deceleration rate data is exceeded, the subtraction value discrimination circuit 15 outputs a logic signal "1" representing "abnormal deceleration".

As a result, by the action of the OR circuit 16, the erroneous "stopping" output "0" is corrected to "1" representing "running" by "1" representing "abnormal deceleration", and As a result, "1" representing "running" is continuously supplied to the AND circuit 5, so the light 7 is not turned off and remains lit.

As mentioned above, in the vehicle light control device of this example, even if the pulse train suddenly stops being supplied due to a failure of the vehicle speed sensor during night driving, etc., the AND circuit 5 continues to be supplied with the "driving signal". Since a logic signal corresponding to "in" is supplied, there is no possibility of erroneously determining that the vehicle is "stopped" and turning off the light.

FIG. 4 is a block diagram showing the electrical configuration of an embodiment (hereinafter referred to as a second embodiment) in which the vehicle light control device of the present invention is constructed using a microcomputer. In addition, in the figure, the same reference numerals are given to the same components as in the above embodiment, and the explanation thereof will be omitted.

In the figure, 18 is, for example, a one-chip microcomputer installed in this type of vehicle.
In the figure, A and B are its input ports, C is its output port,
18a is a group of registers for calculations, 18b is a memory section composed of a ROM for storing system programs, a working RAM, etc., and 18c is a numerical logic operation section (hereinafter referred to as ALU). Note that since various basic operations of this type of microcomputer are well known, a description thereof will be omitted.

The illuminance data output from the optical sensor 1 is sent to the computer 18 through an A/D converter 19.
The counting data supplied from the pulse counter 11 is supplied to the input port B.

FIG. 5 is a flowchart showing only the structure of the light control program according to the present invention among the various vehicle control system programs stored in the memory section 18b of the microcomputer 18, and the following will be based on this flowchart. The operation of the second embodiment will now be explained.

First, in step 1, the outside illuminance data output from the A/D converter 19 is read and temporarily stored in a predetermined register, and then the process proceeds to step 2, where the illuminance data read and the outside illuminance data previously stored in memory are stored. A subtraction comparison is made with contrast threshold data for determining the brightness and darkness of illuminance.

Next, the process proceeds to step 3, and as a result of the comparison in step 2, if the illuminance data is greater than the threshold data, it is determined that the illuminance outside the vehicle is "bright," and the process proceeds to step 4, whereby a lights-off instruction signal is issued. The light is supplied to the drive circuit 6, and the light 7 is automatically turned off (if it has been turned off, it continues to be turned off. The same applies hereinafter).

Further, in step 3, if the illuminance data is smaller than the threshold value data, it is determined that the illuminance outside the vehicle is "dark", and the process proceeds to step 5.

In step 5, the pulse number data per unit time output from the pulse counter 11 is read and stored in the first pulse number register, and then the process proceeds to step 6, where the pulse number data from the pulse counter 24 is read again after the unit time has elapsed. It is read and stored in the second pulse number register, and the process proceeds to step 7.

In step 7, subtraction is performed between the pulse number data in the first and second pulse number registers, and the result of this operation is stored as deceleration rate data in the deceleration rate register.

Next, the process proceeds to step 8, where the deceleration rate data stored in the deceleration rate register is subtracted and compared with the maximum deceleration rate (for example, deceleration rate at sudden stop) data stored in the memory in advance. Proceed to step 9.

In step 9, if the deceleration rate data is smaller than the maximum deceleration rate data as a result of the comparison in step 8, the process advances to step 10, and the presence or absence of a pulse signal is determined based on the latest pulse number data that has already been taken in. However, if the result is "with pulse", it is determined that the vehicle is "running" and step 1 is executed.
Proceeding to step 2, a transfer instruction signal is supplied to the drive circuit 6,
The light 7 is automatically turned on (if it is turned on, it continues to be turned on. The same applies hereinafter).

On the other hand, if the judgment result is "no pulse", the process advances to step 11 to determine the state of the abnormality flag F, and if it is "0", the process advances to step 13 to supply a light-off instruction signal to the drive circuit 6. , the light is automatically turned off, and in the case of "1", the process advances to step 12 and the light is maintained in the lit state.

On the other hand, in step 9, step 8
If the deceleration rate calculated is determined to be larger than the maximum deceleration rate data, it is assumed that abnormal deceleration has occurred due to a failure etc., and the abnormality flag F is set to "1".
Next, the process proceeds to step 12, where a lighting instruction signal is continuously supplied to the drive circuit 6 to maintain the light 7 in the lighting state. As a result, the lights will not be turned off due to a false determination that the vehicle has stopped running, and the vehicle will be able to drive safely.

In each of the embodiments described above, when abnormal deceleration is determined, an alarm drive instruction signal may be outputted accordingly to drive the alarm device to notify that an abnormality has occurred.

As explained above in detail, in the vehicle light control device of the present invention, when the signal from the vehicle speed sensor is no longer supplied due to a vehicle speed sensor failure or the like during night driving, "travel stop" occurs. The vehicle speed deceleration rate determined based on the change in the output from the vehicle speed sensor at that point in time is determined to be an abnormal deceleration, and the light is kept on, thereby improving safety. can.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the schematic configuration of a conventional vehicle light control device, FIG. 2 is a block diagram showing the electrical configuration of the main parts of the vehicle light control device according to the first embodiment, and FIG. 4 is a block diagram showing a second embodiment of the present invention, and FIG. 5 is a flow chart for explaining the operation. 1... Light sensor, 2... Vehicle speed sensor, 3... Light/dark judgment circuit, 5... AND circuit, 10... Running/
Stop determination circuit, 13...subtraction circuit, 15...subtraction value discrimination circuit.

Claims (1)

[Scope of Claims] 1. For a vehicle that determines whether the vehicle is running based on the output of a vehicle speed detector and turns on the lights by a light lighting signal when it is determined that the outside illuminance has decreased based on the output of the vehicle exterior illuminance detector. In the light control device; a deceleration rate calculation means for calculating a deceleration rate based on the output of the vehicle speed detector; and a deceleration rate calculation means for determining whether the deceleration rate calculated by the deceleration rate calculation means exceeds a preset maximum deceleration rate. A vehicular light control device comprising: abnormal deceleration determining means for determining whether the abnormal deceleration occurs; and correction means for outputting a light lighting signal when the abnormal deceleration is determined.