JPH05221289A - Wiper control device - Google Patents

Abstract

PURPOSE:To drive a wiper blade at an optimum wiping time interval agreeing with a feeling of a driver even at the time of very small rainfall such as at the time of running in a tunnel with no vehicle running ahead. CONSTITUTION:In a wiper control device which integrates an output from a rainwater drip sensor 21 to drive a wiper blade in the point of time any earlier of the point of time an integrated value of the output reaches a threshold value or more and of the point of time a predetermined intermittent time elapsed after ending wiping action in the preceding time, in a condition that the device is operated in an INT mode by setting the intermittent time to a maximum value, after a wiper switch 2 is once selected to an LO mode by an operator feeling the intermittent time long, when the device is switched again to the INT mode within a predetermined time, the before-mentioned maximum value is corrected long. Thus, the intermittent time at the time of very small rainfall is corrected to reduce complicated LO/INT operation by the operator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper control device which is suitable for use in a vehicle and drives a wiper blade at a wiping interval suitable for a rainfall condition.

[0002]

2. Description of the Related Art A so-called automatic wiper control device, which controls the wiper operation based on the output of a raindrop sensor when the INT contact of a wiper switch is turned on, integrates values based on the output from the raindrop sensor, and the integrated value. Is greater than or equal to a predetermined threshold value, or a predetermined intermittent time has elapsed from the end of the last wiping operation of the wiper blade, whichever is earlier, which is configured to start the wiping operation of the wiper blade Has been done.

Therefore, for example, when an automobile enters a tunnel and there is no preceding vehicle, the amount of raindrops attached to the windshield is extremely small. In such a situation, the integrated value does not exceed the threshold, and therefore the step of intermittent time is, for example, 1.5.
Each time the intermittent time is updated, the step is changed to a long step, such as 3 seconds to 3 seconds, 3 seconds to 6 seconds, and 6 seconds to 12 seconds.

However, when the intermittent time reaches the maximum value, for example, 24 seconds, it is 1 more than the maximum value.
There is a big difference from a short step, for example, 12 seconds, and the driver may feel that the maximum value is too long. In such a case, the driver switches the wiper switch from the INT contact to the LO contact, wipes the wiper blade one or more times, and then performs the IN operation again.
Return to T contact. Therefore, in such a case of extremely light rain, the operation may be complicated depending on the rainfall condition.

[0005]

In order to solve the above-mentioned problems, in a typical prior art, a sensitivity adjusting volume or the like is provided, and the threshold value is corrected in response to a change in the resistance value of the volume. Is configured to.

However, in the above-mentioned conventional technique, not only the maximum value but also the relatively short intermittent time such as 1.5 seconds and 3 seconds described above fluctuates. Therefore, there is a problem that the sensitivity must be adjusted according to the rainfall condition.

An object of the present invention is to provide a wiper control device capable of correcting the intermittent time during extremely light rain according to the driver's feeling.

[0008]

SUMMARY OF THE INVENTION The present invention provides a wiper switch that is manually operated by an operator to switch the operating state of a wiper blade between at least a continuous operating state and an intermittent operating state at a predetermined intermittent time. , A raindrop sensor for detecting a rainfall state, a drive means for reciprocatingly driving a wiper blade for removing raindrops adhering to the surface to be wiped on the surface to be wiped, and the intermittent operation state is selected by the wiper switch. When it is, the value based on the output from the raindrop sensor is integrated, and the integrated value is equal to or more than a predetermined threshold value within a predetermined intermittent time after the last wiping operation of the wiper blade, and the intermittent time. Control means for outputting a drive signal indicating that the wiper blade should be driven to the drive means at the earlier of the elapsed time, and In response to the operation of the wiper switch, the operating state is once switched to the continuous operating state with the intermittent time of the control means being selected to the maximum value, and then the intermittent operating state is restored within a predetermined time. In this case, the wiper control device further includes a correction unit that corrects the maximum value of the intermittent time to be short.

Further, the correction means of the present invention sets the maximum value of the intermittent time to the time from the end of the previous wiping operation of the wiper blade to the switching to the continuous operation state, and corrects the maximum value. It is characterized by performing.

[0010]

According to the present invention, when the wiper switch is manually operated by the operator and the intermittent operation state of the wiper blade is selected, the control means integrates the values based on the output from the raindrop sensor, and the integrated value is calculated. The drive signal is output to the drive unit at the earlier of the time when the predetermined threshold value is exceeded or the time when the predetermined intermittent time has elapsed from the end of the previous wiping operation of the wiper blade. The driving means is
In response to the drive signal, the wiper blade is driven to reciprocate on the surface to be wiped such as the windshield to remove raindrops and the like adhering to the surface to be wiped.

The control means also updates the intermittent time based on the time required for the integrated value to become the threshold value or more, the integrated value at the time when the intermittent time has elapsed, and the like.

A correction means is provided in association with the control means, and the correction means is responsive to the operation of the wiper switch, and the intermittent time of the control means is selected to the maximum value, that is, the pole. During a light rain, when the operating state of the wiper blade selected by the wiper switch is switched from the intermittent operating state to the continuous operating state and then returned to the intermittent operating state again within a predetermined time, Correct the maximum value shorter. The corrected maximum value of the intermittent time may be, for example, a value near the center between the maximum value during normal rainfall and the intermittent time that is one step shorter than the maximum value, or the previous wiping of the wiper blade. It may be set to the time from the end of the operation to the switching to the continuous operation state.

Therefore, in a very small amount of rain such as in a tunnel where the amount of raindrops attached is extremely small and the intermittent time becomes the maximum value, the operator judges that the intermittent time is too long, and once the continuous operation state is reached. When switching to
The maximum value of the intermittent time is corrected to be short. In this way, the maximum value of the intermittent time at the time of extremely light rain is corrected to be short without changing the intermittent time at the time of normal rainfall, and the complicated operation of the driver is reduced.

[0014]

1 is a block diagram showing the electrical construction of a wiper control apparatus 1 according to an embodiment of the present invention. In this wiper control device 1, a driver, who is an operator, operates the wiper switch 2 to set the wiper motor 3 that is a driving unit to an OFF mode that is a stop mode, an INT mode that is an intermittent mode, and a low speed continuous operation. The operating mode, LO
Mode and HI mode, which is a high-speed continuous operation mode,
It can be driven in three operating modes.

Therefore, the wiper switch 2 provided on the steering column or the like switches to the switching state as shown in FIG. 1 in accordance with the operation mode. The wiper switch 2 has, for example, four contacts + B,
It has +2, INT, and +1. In the OFF mode, there is no conduction between the contacts, in the INT mode, the contact + B and the contact INT are conducted, in the LO mode, the contact + B and the contact +1 are conducted, and in the HI mode, the contact + B and the contact +2. Conducts.

The contact + B is connected to the power supply line 5 from the battery 4 through the fuse 7 and the ignition key switch 8. Remaining contact points +2, INT, +
1 is an input circuit 12 to 1 in the auto wiper control circuit 11.
4 are connected to each, and the auto wiper control circuit 1
The processing circuit 15 in 1 detects the switching state of the wiper switch 2 via the input circuits 12 to 14.

The automatic wiper control circuit 11 includes the processing circuit 15, input circuits 12 to 14 and 16, constant voltage circuits 17 and 20, relays 18 and 19, and a raindrop sensor 21.
And a waveform shaping circuit 22.

Noise components such as chattering are removed by the input circuits 12 to 14 and the switching state of the wiper switch 2 is read into the processing circuit 15 realized by a microcomputer or the like. Processing circuit 1
The output from the raindrop sensor 21 for detecting the rainfall state is input to the waveform 5, after being shaped into a rectangular wave pulse by the waveform shaping circuit 22. The processing circuit 15 responds to the inputs from the wiper switch 2 and the raindrop sensor 21 to selectively control the relays 18 and 19 to control the operation of the wiper motor 3.

That is, when the wiper motor 3 is continuously driven at a low speed, the processing circuit 15 derives a high level drive signal from the output terminal P2. As a result, the relay coil 23 of the relay 19 is excited, and the common contact 24a of the relay switch 24 conducts to the individual contact 24b. Therefore, the power from the power supply line 5 is transferred from the contacts 24b and 24a of the relay switch 24 to the relay switch 2 of the relay 18.
It is supplied to the low speed power supply input terminal 3a of the wiper motor 3 via the contacts 26a and 26b of No. 6.

When the wiper motor 3 is continuously driven at high speed, the processing circuit 15 derives a high level drive signal from the output terminal P2 as well as from the output terminal P2. As a result, the relay coil 25 of the relay 18 is excited, and the common contact 26a of the relay switch 26 is electrically connected to the individual contact 26c. Therefore, the electric power from the battery 4 from the power supply line 5 through the contacts 24b and 24a of the relay switch 24 is the contact 26a of the relay switch 26,
It is supplied to the high speed power input terminal 3b of the wiper motor 3 via 26c.

On the other hand, a cam switch 6 is provided in association with the wiper motor 3, and the common contact 6a of the cam switch 6 is provided with the ground terminal 3c of the wiper motor 3 when the wiper blade is in the initial position. It is electrically connected to one individual contact 6b which is grounded. When the wiper motor 3 is activated and the wiper blade starts the wiping operation, the common contact 6a of the cam switch 6 is electrically connected to the other individual contact 6c connected to the power supply line 5. In this way, the potential of the common contact 6a changes depending on whether or not the wiper blade is in the wiping operation,
The change in the potential is input from the line 29 to the processing circuit 15 via the input circuit 16.

Therefore, the processing circuit 15 continues to derive a high level output from the output terminal P2 even after the wiper motor 3 is once activated and the OFF mode is selected by the wiper switch 2 during the wiping operation of the wiper blade. Return the wiper blade to the initial position. When the wiper blade returns to the initial position in this way, the common contact 6a of the cam switch 6 is electrically connected to the individual contact 6b, and the output terminal P2 of the processing circuit 15 becomes low level. When the wiper motor 3 is not continuously operated in this state, the relay switch 24
The common contact 24a of the cam switch 6 is electrically connected to the individual contact 24c. Therefore, the contacts 6b and 6a of the cam switch 6, the contacts 24c and 24a of the relay switch 24, and the relay switch 2 are connected.
6 via the contacts 26a, 26b of the wiper motor 3
A brake current flows through the low speed power supply input terminal 3a, and the wiper motor 3 stops.

Further, when the wiper switch 2 is selected in the INT mode and the wiper motor 3 is intermittently driven, the processing circuit 15 integrates the pulse width of the rectangular wave pulse from the raindrop sensor 21 via the waveform shaping circuit 22. Driving from the output terminal P2 at the earlier of the time when the integrated value M1 becomes equal to or greater than a predetermined threshold value RP or the time when a below-described intermittent time WOT measured by the counter 27 has elapsed. Output a signal. In this way, the wiper motor 3 is driven at the wiping interval suitable for the rainy state.

The intermittent time WOT can be selected from, for example, seven steps as shown in Table 1. Therefore, when the first step is selected, the wiper motor 3 is in a high speed continuous operation state, when the second step is selected, it is in a low speed continuous operation state, and when the third step is selected, it is 1.5 seconds. It is set to intermittent operation state, and then 4 seconds for 3 seconds, 5 seconds for 6 seconds,
The intermittent operation state is set for 12 seconds in the sixth step and 24 seconds in the longest seventh step.

[0025]

[Table 1]

When the integrated value M1 is equal to or more than the threshold value RP, each step is set based on the time WCT from the end of the previous wiping operation of the wiper blade until the integrated value M1 is equal to or greater than the threshold value RP. To be done. Further, when the integrated value M1 is less than the threshold value RP even after the intermittent time WOT has elapsed, the above steps are set based on the integrated value M1 at the time when the intermittent time WOT has elapsed.

That is, for example, the intermittent time WOT of 80
% Within the time WUP, the integrated value M1 is equal to the threshold value RP.
In the above case, the step of the intermittent time WOT is set lower by one step, and the intermittent time is changed to be shorter. On the other hand, when the intermittent value WOT has elapsed and the integrated value M1 is less than the value MDN that is 1/2 of the threshold value RP, the step of the intermittent time WOT is changed by one step. Thresholds for such step changes are shown in FIG. The operation of updating the intermittent time WOT as described above,
The automatic wiper control is realized by performing the operation of integrating the output of the raindrop sensor 21.

Electric power from the battery 4 via the power supply line 5 is supplied to the terminal Vcc of the processing circuit 15 after being stabilized by the constant voltage circuit 17 as electric power for arithmetic processing. Further, the electric power from the battery 4 supplied from the upstream side of the ignition key switch 8 via the line 30 is supplied to the terminal Vdd of the processing circuit 15 by the constant voltage circuit 2.
After being stabilized at 0, it is supplied as backup power.

The wiper control device 1 configured as described above
In the processing circuit 15, which is also a correction means, in the state where the intermittent time WOT is set to the longest seventh step,
When the wiper switch 2 is once switched from the INT mode to the LO mode and then to the INT mode again within a predetermined time T1, for example, 3 minutes, when the LO / INT switching operation is performed twice, It is determined that the wiping operation is performed at a timing later than the timing at which the operator feels comfortable, and the intermittent time of the seventh step is corrected from 24 seconds to 16 seconds. Therefore, the processing circuit 15 is also provided with a counter 28 for measuring the time T1.

3 and 4 are flowcharts for explaining the automatic wiper control operation including the intermittent time correction operation as described above. In step n1, flags F1 to F6, which will be described later, the integrated value M1 and the count value WC
Initialization processing of T and KT is performed. In step n2,
It is determined whether or not the wiper switch 2 is selected in the OFF mode, and if so, the processing circuit 15 stops the output of the drive signal from the output terminals P1 and P2 and stops the wiper motor 3 in step n3. Let In step n2, when the wiper switch 2 is not selected in the OFF mode, the process proceeds to step n4,
It is determined whether or not the HI mode is selected, and if so, the process proceeds to step n5 to output terminals P1 and P2.
Outputs a high level drive signal from the wiper motor 3
Is driven continuously at high speed.

As described above, when the steps n2 to n5 are in the OFF mode or the HI mode other than the INT mode or the LO mode, in steps n6 to n10, the count value CT described later, the count value KT of the counter 28, and the shortening are described. After the flag F4, the INT flag F5, and the permission flag F6 are reset to zero, the process returns to step n2.

In step n4, when the wiper switch 2 is not selected in the HI mode, the process proceeds to step n11, and it is determined whether or not it is selected in the LO mode.
It is determined whether or not the INT flag F5 indicating that the mode is operating is zero. As a result, the INT flag F
When 5 is zero, that is, when the mode is changed from the OFF mode or the HI mode to the LO mode, step n2
After moving to 0, the processing circuit 15 outputs a drive signal from the output terminal P2 to drive the wiper motor 3 at a low speed, and then returns to step n2, otherwise moves to step n13.

At step n13, the permission flag F6 indicating that the INT mode has once been changed to the LO mode is set to 1, and at step n14, the INT flag F5 is reset to zero. In step n15,
The count value CT of the counter for counting the number of times of shifting from the INT mode to the LO mode is added and updated. In step n16, step n23, which will be described later,
Within the time T1 measured at n24, the count value C
It is determined whether or not T is 2 or more. If not, the process proceeds to step n20, and if so, to step n17.

At step n17, the intermittent time WOT is set.
Shortening flag F4 indicating that the seventh step of
Is set to 1. Then, steps n18 and n19
In step n20, the count value KT and the permission flag F6 are reset to zero, and the wiper motor 3 is driven at a low speed in step n20. Then, the process returns to step n2.

When it is not the LO mode in step n11, that is, when it is the INT mode, the process proceeds to step n21, and the INT flag F5 is set to 1. In step n22, it is judged whether or not the permission flag F6 set in step n13 is zero,
If not, that is, if the INT mode is once switched to the LO mode and then returned to the INT mode, the process moves to step n23, the counter 28 performs the counting operation, and the count value KT is updated.
At step n24, it is judged whether or not the count value KT has become equal to or more than the predetermined time T1, and if so, that is, within the time T1, the LO of the wiper switch 2 is changed.
When the / INT switching operation has not been performed twice, the count values CT and KT and the flag F6 are reset to zero in steps n25, n26 and n27.

In step n22, when the permission flag F6 is zero, that is, when the mode other than the LO mode is changed to the INT mode, and step n
24, when the count value KT is less than the time T1, and from step n27, step n3
The operation proceeds to the pulse integration operation after 1 and the operation of updating the intermittent time WOT.

At step n31, the detection output Ma of the raindrop sensor 21 is added to the integrated value M1 to update the integrated value M1. At step n32, it is judged whether or not the integrated value M1 is equal to or more than the threshold value RP. And if not,
That is, when it is less than the threshold value RP, the process proceeds to step n33. In step n33, the count value WCT of the counter 27 is added to perform the counting operation, and step n33
At 34, it is determined whether or not the count value WCT is equal to or longer than the predetermined intermittent time WOT, and if not, the process returns to step n2.

In step n32, the integrated value M1
Is equal to or greater than the threshold value RP, and when the count value WCT is equal to or greater than the intermittent time WOT in step n34, the following step change of the intermittent time WOT and the wiper operation are performed. That is, step n32
When the integrated value M1 is greater than or equal to the threshold value RP, the process proceeds to step n41, and it is determined whether or not the count value WCT of the counter 27 is within the time WUP that is 80% of the intermittent time WOT, and if so, Step n42
The flag F1 for reducing the step of the intermittent time WOT is set to 1, and the flag F2 for holding the step and the flag F for reducing the step are set.
Both 3 and 3 are reset to zero.

When the count value WCT exceeds the time WUP in step n41, the process moves to step n43, the flag F2 is set to 1 and both flags F1 and F3 are reset to zero. Furthermore, in step n34, the count value WCT
Is over the intermittent time WOT, step n44
And the integrated value M1 at that time is 1 of the threshold value RP.
It is determined whether or not the value is less than the value MDN which is / 2, and if not, the process moves to step n43 and the step is held, and if so, the flag F3 is set to 1 and the flag is set at step n45. F1,
F2 is reset to zero.

In steps n43 and n45, if it is selected that the step of the intermittent time WOT should be held or increased, the process proceeds to step n46, and whether the step of the intermittent time WOT has already been set to the seventh step or not. It is determined, and if so, the process moves to step n47. In step n47, it is determined whether or not the shortening flag F4 set in step n17 is set to 1, and if so, in step n48, the intermittent time WOT of the seventh step is set to the original seventh step. 16 seconds which is a correction of 24 seconds which is the value of is set. In step n47, when the shortening flag F4 is not 1, in step n49, the intermittent time WOT is set to 24 seconds which is the original value of the seventh step.

In step n46, when the step of the intermittent time WOT is not the seventh step, and from step n42 to step n50, the process corresponds to the flags F1 to F3 set in step n42, n43 or n45. Then, the step of the intermittent time WOT is set.

When the intermittent time WOT is set in step n48, n49 or n50 in this way, the process proceeds to step n51, the integrated value M1 is set to zero, and further in step n52 the count value WCT is reset to zero. .. Then, in step n53, the wiper motor 3 is driven to perform the wiping operation including the high speed continuous operation, and then the process returns to step n2.

Thus, the wiper control device 1 according to the present invention
Then, when the wiper switch 2 is switched from the INT mode to the LO / INT switching operation twice within the predetermined time T1 while the intermittent time WOT is set to the maximum value of the seventh step, that is, If the operator feels that the maximum value of the intermittent time WOT is later than the comfortable wiping timing, the wiper switch 2 is switched to the LO mode, the wiping operation is performed, and then the operation is switched to the INT mode again. The intermittent time of the seventh step of the time WOT is switched from 24 seconds in the normal control to 16 seconds. As a result, the maximum value of the intermittent time WOT is corrected according to the sense of the operator in the case of extremely light rain such as when traveling in a tunnel without a preceding vehicle without changing the remaining steps. The wiper control can be performed in accordance with the feeling of the operator.

When the amount of rainfall is extremely small, the intermittent time WOT is changed to the maximum value of the seventh step, and the wiper blade can be driven at an appropriate wiping interval sufficiently longer than the sixth step.

After the power is turned on, during the first operation in the INT mode, the intermittent time WOT is set to 24 seconds of the seventh step to perform the initial operation, and the counter 28 is the elapsed time after the initial operation. To count.

In the above-described embodiment, the preset value of 16 seconds is used as the correction value for the seventh step of the intermittent time WOT. However, as another embodiment of the present invention, the wiper blade in the INT mode is set to the previous time. After the wiping operation of
You may make it correct | amend by the time until it switches to O mode. As a result, the wiper switch 2 is once switched from the INT mode to the LO mode, and then the
When the T mode is selected, the wiping operation can be performed in the intermittent time when the operator feels comfortable.

[0047]

As described above, according to the present invention, when the intermittent time is selected to be the maximum value, the driver who is the operator judges that the intermittent time is too long, and once the wiper switch is pressed. After selecting the continuous operation state, when returning to the intermittent operation state again, since the maximum value of the intermittent time is corrected to be short, without changing the intermittent time during normal rainfall,
It is possible to correct only the maximum value of the intermittent time at the time of extremely light rain to reduce the complicated operation of the driver and drive the wiper blade at an optimum wiping interval that matches the driver's feeling.

[Brief description of drawings]

FIG. 1 is a block diagram showing an electrical configuration of a wiper control device 1 according to an embodiment of the present invention.

FIG. 2 is a diagram showing a threshold value for step change of an intermittent time WOT.

FIG. 3 is a flow chart for explaining an auto wiper control operation of an embodiment of the present invention.

FIG. 4 is a flowchart illustrating an automatic wiper control operation according to an exemplary embodiment of the present invention.

[Explanation of symbols]

 1 wiper control device 2 wiper switch 3 wiper motor 6 cam switch 11 auto wiper control circuit 15 processing circuit 21 raindrop sensor 27, 28 counter

Claims (2)

[Claims] 1. A wiper switch, which is manually operated by an operator, for switching the operating state of the wiper blade to at least a continuous operating state and an intermittent operating state at a predetermined intermittent time, and a raindrop sensor for detecting a raining state. Driving means for reciprocating the wiper blade for removing raindrops adhering to the surface to be wiped on the surface to be wiped, and when the intermittent operation state is selected by the wiper switch, from the raindrop sensor. The value based on the output is integrated, and the integrated value is equal to or greater than a predetermined threshold value within a predetermined intermittent time after the end of the last wiping operation of the wiper blade, or the time when the intermittent time has elapsed, whichever comes first. And a control means for outputting to the drive means a drive signal indicating that the wiper blade should be driven, and an operation of the wiper switch. In response, when the intermittent time of the control means is selected to the maximum value, when the operation state is once switched to the continuous operation state and then returned to the intermittent operation state within a predetermined time, the intermittent operation is performed. A wiper control device comprising: a correction means for correcting the maximum value of time to be short. 2. The correcting means sets the maximum value of the intermittent time to the time from the end of the last wiping operation of the wiper blade to the switching to the continuous operation state, and corrects the maximum value. The wiper control device according to claim 1.