JPH0257455A - Raindrop-sensitive automatic control device - Google Patents

Abstract

PURPOSE:To accomplish stable intermittent wiping operation during a fixed time even if stochastic scattering is caused in rain drops contacting a sensor by providing some fixed intermittent times and adopting a method of controlling the transition between intermittent modes according to the quantity of rain. CONSTITUTION:According to an output signal of a rain sensor 1, a raindrop signal extracted in raindrop detecting means 2 is integrated by integrating means 4, and the integration result is compared with the first and second threshold values. The comparison result is sent to a control block 7, and according to the comparison result and an output signal of time measuring means 8, the operation of a wiper motor 11 is controlled through a motor driving circuit 10. The time measuring means 8 is provided for outputting a time signal to time based on the storage content stored in a management block 9 for an intermittent mode, and a control block 7 is adapted to change the above storage content into a long intermittent mode when the integration output is smaller than the first threshold value and change the storage content into a short intermittent mode when it is larger than the second threshold value.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a wiper control device for a vehicle that uses a rain sensor to control wiper wiping according to rain conditions.

[Prior Art] Conventionally, in automatic wiper control, there is a demand for constant wiper wiping when the rain condition is constant.

[Invention tries to solve! ! IF) However, as shown in Utility Model Publication No. i3-26467, the system that operates intermittently when the accumulated value of the raindrop signal reaches a certain level, as shown in Figure 8, There was a problem that the intermittent time also varied due to stochastic variations.In Figure 8, (
(a) shows raindrops, (b) shows an integrated value, and (C) shows wiper wiping.

Further, as shown in Japanese Utility Model Application Publication No. 63-21174, a method in which a certain amount of wiping is maintained for a certain period of time has a problem in that the responsiveness to sudden changes in rainfall is insufficient.

Therefore, in the present invention, even if the rain that hits the sensor varies stochastically, the same intermittent time can be maintained as long as the rain condition is constant, and it is also possible to instantly respond to sudden changes in rain ffi'. An automatic wiper control device is provided.

[Means to solve the problem]

In order to achieve the above object, the present invention employs a system that has several fixed intermittent times and controls the transition between the 11 intermittent modes depending on the amount of rainfall. Of course, the present invention provides a wiper drive circuit that drives a wiper.
A rain sensor for detecting rain, a rain detection means for extracting a raindrop signal from the m-mow signal, an integration means for integrating the raindrop signal, a time measurement means for measuring time, and a wire bar. Resetting means for resetting the integrating means and the time measuring means when wiped; first and second ratio calculating means for respectively comparing the output of the integrating means and an eleventh second threshold; a storage means for storing the intermittent mode;
control means for controlling the operation of the wiper and the storage contents of the 1rI storage means based on the comparison results of the first and second comparison means and the signal of the time measurement means; 1.9 Contents of means 2. (The control means outputs a time signal at the time when the time signal is generated, and if the output signal of the integrating means is smaller than the first threshold value when the time signal is generated, the control means stores the stored contents of the storage means in a long period of time.) mode, and if the output signal of the integrating means is larger than the second threshold value, change the content of α to the short intermittent mode and change the content of α to the short intermittent mode, and when the output signal of the integrating means is larger than the second threshold value. Features.

〔Example] Embodiments of the present invention will be described below based on the drawings.

FIG. 1 shows a block diagram of this embodiment, and reference numeral 1 denotes a sensor for detecting rain, which is installed on the hood or bumper of a vehicle. As the sensor l, there are capacitance type, piezoelectric type, optical type, etc. Raindrop detection means 2
detects the raindrop signal from the output signal of sensor 1 and outputs signal 2a.
Output. The raindrop detection means 2 is set according to the sensor method of the sensor I. The discrimination means 3 discriminates between raindrop signals and noise, and outputs a signal 3a for a certain period of time if the output 2a exceeds a certain value. 4 integrates the raindrop signal, and integrates the output 2a while the output 3a is at a high level (hereinafter referred to as "1"). The li'f minute value is compared with two reference values and the result is 4a.

41). Reference numeral 6 denotes a volume J for adjusting sensitivity, and is installed at a location where the driver can easily enjoy comics.

The volume detecting means 5 detects the value of poly1-mulo, and the result is outputted as a signal 5a. This output 5a controls the internal reference value of the integration 4.

The time measuring means 8 outputs the elapsed time since the previous wiping as a signal 8a. Furthermore, with reference to the mode information 9a, the signal 8b is output when the intermittent time of the current mode has arrived.

Furthermore, the time is cleared using the input cuff b. 7 is a control block, which includes rainfall information 4a, 4b, and time pulse 8b.
wiping pulse 7a and mode transition signals 7c, 7 based on
d. Output pulse 7b for clearing time and rainfall. 9 is an intermittent mode management block, and a mode transition signal 7c
, 7d and time information 8a, and outputs a signal 9a indicating the current intermittent mode. Furthermore, continuous wiping at low speed and continuous wiping at high speed are each treated as one of the modes. A motor drive circuit 10 drives the wiper motor 11 based on the signal of the mode information 9a1 and the wiping pulse 7a. Reference numeral 11 is a motor for an i-neiper that wipes the windshield and the like.

Next, the operation of the above device will be explained.

FIGS. 2 to 7 show the processing flow of the configuration shown in FIG. 1, and the steps from 5TART in FIG. 2 to FIG. 7 are repeated at regular intervals as one cycle.

FIG. 2 shows the processing of the identification means 3 of FIG.

In step 101, it is determined whether the input is greater than or equal to a threshold value. If the value is below the threshold value, it is considered as noise and the input permission flag is not set. If the threshold value is exceeded, an input permission flag is set for a certain period of time. Incidentally, this time may be set to approximately the reaction time of the sensor I due to one raindrop.

FIG. 3 shows the processing of the integrating means 4 of FIG.

If there is a reset input, the integrated value is cleared in step 111. The integration process is performed in step 114, but it is determined that the input flag is set by Gf in step 113.
Since L'yt, only the raindrop signal is added to S. Since the reset input is performed at the time of wiping with the wiper, the integrated value S of the raindrop signals since the previous wiping can be obtained. This integrated value S and base? iζ value refl,
By comparing it with ref2 and outputting it, it is possible to know whether or not specified raindrops have adhered.

Sensitivity can be adjusted by changing rerl and rer2 depending on the volume value.

FIG. 4 shows the processing of control block 7 in FIG.

If the ladγ output 4a is "11", it means that the specified upper limit of raindrops has adhered to the windshield.Therefore, it is necessary to shorten the intermittent time, so the mode transition signal 7C is output and the wiper is wiped immediately. and brush the raindrops off the windshield. Since the raindrops have been removed, a reset pulse 7b is output to clear the integration and time.

If the integration output 4a is at a low level (hereinafter referred to as "L"), processing is performed when the time indicated by the current intermittent mode arrives. If the integrated output 4b is rH at this point, it means that the raindrops attached to the windshield are between the specified upper and lower limits, and in this case, the current intermittent time is appropriate. So, at this point, wipe it off with a wiper.

At this time, the intermittent mode is not changed.

In step 123, if the integrated output 4b is "L", it means that the number of raindrops attached to the windshield has not reached the specified lower limit, and in this case, the wiper is not wiped yet and the intermittent mode down signal 7d It just outputs . Since the integration and time are not cleared, the time pulse 8b is rH at the time in the changed intermittent mode.
J, and step 123 is re-determined. Assuming that the intermittent time before the change is TI, and the 1 rank longer 1■ intermittent time is T2, the time until this re-judgment is performed is (1' 2 - T
1).

Even at the time of re-judgment, when the integration output 4b is "I5", the intermittent mode is sequentially turned down.

When the amount of rainfall increases, step 120 → step 121
If the rainfall decreases along the route, step 122 →
Step 123→Step 125, and if the rainfall does not change, Step 122-) Step 1
Processing is carried out along the route 23→step 124.

FIG. 5 shows the processing of the time measuring means 8 of FIG.

Resetting is done when the wiper is used to clear the time. At the time indicated by the intermittent mode 9a, a time pulse 8b is output, and the elapsed time is always output to 8a.

FIG. 6 shows the processing of the management block 9 in FIG.

Mode UP is performed in step 141, and the closest intermittent mode that is shorter than the elapsed time 8a at that time is selected.

Mode down is performed in step 143, and the intermittent mode is lowered by one rank. 'In addition, the mode down is 11
As the processing is performed sequentially and continuously as described in f, it is possible to cope with a sudden decrease in rainfall.

Note that continuous wiping at low speed and continuous wiping at high speed are handled in the same way as the intermittent mode in the form of short intermittent time modes.

FIG. 7 shows the processing of the motor drive circuit 10 of FIG.

- High-speed driving of the Neuva motor is processed through the path from step 150 to step 151, and low-speed driving of the wiper motor is processed through the path from step 152 to step 157. Regarding the intermittent drive of the wiper motor, in step 154 the intermittent O
N time is set and the wiper motor is driven for this time.

FIG. 8 is a diagram for explaining the operation of this embodiment, and (a)
(1)) shows the integrated value, and (C) shows the wiper wiping.

As explained in detail above, in this embodiment, even if there are stochastic variations in the raindrops hitting the sensor, it is possible to perform stable and intermittent wiping for a certain period of time, and moreover, when the amount of rain increases or the number of raindrops decreases, new raindrops can be quickly removed. It is possible to shift to the intermittent mode, and has the unique effect of being able to maintain the amount of raindrops on the windshield L within a certain range even during the transition process.

Note that although it is described as having several fixed intermittent times, there is no problem with the control of this embodiment even if the increments of these intermittent times are coarse or fine. It may be an almost continuous intermittent time with fine increments.

Even if there is some variation in the intermittent time during long intermittent periods, there is no particular problem, so there is no need to manage at two levels during long intermittent periods. For this reason, it is also possible to perform control for short intermittences as described above, and for long intermittences to be wiped out when the integrated value reaches a certain level. This changes refl and ref2 in Figure 3 to re in a long interval.
This can be obtained by setting fl-ref2. This configuration has the effect that the response when the amount of rain increases and when the vehicle accelerates is even better than the above-mentioned case.

The sensitivity of the sensor may decrease during light rain.
In this case, it is possible to correct this by adding control that wipes away raindrops when they are detected especially during long intervals.

If the wiper is not wiped for a certain period of time, the integrated value is cleared, which is effective in preventing erroneous wiping when there is no rainstorm.

Although it was written that the mode UP process is performed with one mode UP signal, controlling the mode UP signal twice or twice in a row has the effect of achieving even more stable wiping. The same applies to down processing.

In step 141 of FIG. 8, the mode UP process can be changed to the closest mode that is longer than the elapsed time 8a or to a mode that is one rank shorter than the current mode.

〔Effect of the invention〕 .

As explained above, according to the present invention, even if there are stochastic variations in raindrops hitting the sensor, it is possible to perform stable and intermittent wiping for a certain period of time, and when the amount of rain increases or decreases, it can be wiped off immediately. The excellent effect of being able to transition to a new intermittent mode is obtained.

[Brief explanation of the drawing]

Figures 1 to 8 relate to embodiments of the present invention.
2 is a flowchart showing the processing of the identification means 3 of FIG. 1, FIG. 3 is a flowchart showing the processing of the integration means 4 of FIG. 1, and FIG. 1 is a flowchart showing the processing of the control block 7 in FIG. 1, FIG. 5 is a flowchart showing the processing of the time measuring means 8 in FIG. 1, and FIG. 7 is a flowchart showing the processing of the motor drive circuit 10 of FIG. 1, FIG. 8 is a diagram for explaining the operation of this embodiment, and FIG. 9 is a diagram for explaining the prior art of the present invention. This is a diagram. DESCRIPTION OF SYMBOLS 1... Rain sensor, 2... Raindrop detection means, 3... Identification means, 4... Integration means, 5... Volume detection means, 6... Volume, 7... Control block, 8・
... Time measuring means, 9... Management block. Representative Patent Attorney Takashi Okabe Figure 2 Figure 3 Figure 4 +1 Figure 6 w... -1---. ■ Figure 5 negative 171 nq

Claims (3)

[Claims] (1) A wiper drive circuit that drives the wiper includes a rain sensor that detects rain, a raindrop detection means that extracts a raindrop signal from the signal of the rain sensor, an integration means that integrates the raindrop signal, and a timer that measures time. time measuring means; reset means for resetting the integrating means and the time measuring means when the wiper is wiped; and first and second thresholds for comparing the output of the integrating means with first and second thresholds, respectively. 2 comparison means, storage means for storing the intermittent mode, and controlling the operation of the wiper and the storage contents of the storage means based on the comparison results of the first and second comparison means and the signal of the time measurement means. The time measuring means outputs a time signal at a time based on the storage contents of the storage means, and the control means is configured such that the output signal of the integrating means reaches the first threshold when the time signal is generated. If the output signal of the integrating means is greater than the second threshold, the storage contents of the storage means are changed to a long intermittent mode, and when the output signal of the integrating means is greater than the second threshold, the storage contents of the storage means are changed to a short intermittent mode. A wiper driving device characterized in that the wiper driving device drives the wiper while changing the mode. (2) The apparatus according to claim 1, further comprising a sensitivity adjustment means, wherein the sensitivity adjustment means changes both the first and second threshold values. (3) When the intermittent time is greater than a certain value, the first
Claim 1 characterized in that the second threshold values are equal.
The device described.