JP2920845B2 - Wiper control device - Google Patents

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 suitably implemented for a vehicle and drives a wiper blade at a wiping interval suitable for a rainy condition.

[0002]

2. Description of the Related Art When an INT contact of a wiper switch is turned on, a so-called automatic wiper control device for controlling a wiper operation based on an output of a raindrop sensor integrates a value based on an output from the raindrop sensor, and calculates the integrated value. Is configured to start the wiping operation of the wiper blade at the earlier of the time when the predetermined value becomes equal to or greater than the predetermined threshold value and the time when the predetermined intermittent time has elapsed after the end of the previous wiping operation of the wiper blade. Have been.

[0003] Therefore, for example, when an automobile enters a tunnel and there is no preceding vehicle, the amount of raindrops adhering to the windshield becomes extremely small. In such a state, the integrated value does not exceed the threshold, so the step of intermittent time is, for example, 1.5
Every time the intermittent time is updated, it is changed to a longer step, such as from 3 seconds to 3 seconds, from 3 seconds to 6 seconds, from 6 seconds to 12 seconds.

However, if the intermittent time reaches the maximum value, for example, 24 seconds, the intermittent time becomes one more than the maximum value.
There is a significant difference from a shorter 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, performs the wiping operation of the wiper blade one or more times, and then again performs the IN operation.
Return to T contact. Therefore, when the rainfall is extremely small, the operation may be complicated depending on the rainfall state.

[0005]

In order to solve the above-mentioned problems, a typical prior art is provided with a volume for adjusting the sensitivity, and the threshold value is corrected in accordance with a change in the resistance value of the volume. It is configured to be.

[0006] However, in the above-described conventional technique, not only the maximum value, but also the relatively short intermittent time such as 1.5 seconds or 3 seconds described above fluctuates. Therefore, there is a problem that the sensitivity must be adjusted according to the rainfall state.

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

[0008]

SUMMARY OF THE INVENTION The present invention relates to a wiper switch which is manually operated by an operator to switch the operation state of a wiper blade between at least a continuous operation state and an intermittent operation state at a predetermined intermittent time. A raindrop sensor for detecting a rainfall state, a driving unit for reciprocatingly driving a wiper blade for removing raindrops attached to the surface to be wiped on the surface to be wiped, and the intermittent operation state being selected by the wiper switch. The value based on the output from the raindrop sensor is integrated, the time when the integrated value becomes equal to or more than a predetermined threshold within a predetermined intermittent time after the end of the previous wiping operation of the wiper blade, and the predetermined threshold The drive means indicating that the wiper blade should be driven at the earlier of the intermittent time has elapsed and the drive means should be driven. Control means for outputting a signal; and in response to the operation of the wiper switch, the intermittent operation of the control means is selected to be a maximum value. When returning to the state, the wiper control device 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 a time from the end of the previous wiping operation of the wiper blade to the time when the wiper blade is switched 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 a value based on the output from the raindrop sensor, and the integrated value is calculated. The drive means is driven by the drive means at the earlier of the time when the predetermined threshold value or more is reached and the time when the predetermined intermittent time elapses after the end of the previous wiping operation of the wiper blade while remaining below the predetermined threshold value. Output a signal. In response to the driving signal, the driving unit drives the wiper blade to reciprocate on a surface to be wiped such as a windshield to remove raindrops and the like attached to the surface to be wiped.

The control means updates the intermittent time based on a time required until the integrated value becomes equal to or more than the threshold value, an integrated value at the time when the intermittent time has elapsed, and the like.

A correction means is provided in connection with the control means, and the correction means responds to the operation of the wiper switch, and the state in which the intermittent time of the control means is selected to the maximum value, that is, During light rain, when the operation state of the wiper blade selected by the wiper switch is switched from the intermittent operation state to the continuous operation state and then returned to the intermittent operation state again within a predetermined time, Shorten the maximum value. 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 one stage shorter than the maximum value, or the last wiper blade wiping operation. It may be set to the time from the end of the operation to the switching to the continuous operation state.

Therefore, in the case of extremely small rainfall in which the intermittent time becomes the maximum value when the amount of raindrops attached to the inside of the tunnel or the like is extremely small, the operator judges that the intermittent time is too long, and temporarily sets the continuous operating state. 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 the minimum rain is corrected to be short without changing the intermittent time at the time of the normal rain, and the troublesome operation of the driver is reduced.

[0014]

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

Accordingly, the wiper switch 2 provided on the steering column or the like switches to a switching state as shown in FIG. 1 according to the operation mode. The wiper switch 2 has, for example, four contacts + B,
+2, INT, +1. In the OFF mode, none of the contacts conducts, in the INT mode, the contact + B and the contact INT conduct, in the LO mode, the contact + B and the contact +1 conduct, and in the HI mode, the contact + B and the contact +2 connect. Becomes conductive.

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

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

The input circuits 12 to 14 remove noise components such as chattering and read the switching state of the wiper switch 2 into a processing circuit 15 implemented by a microcomputer or the like. Processing circuit 1
5, the output from the raindrop sensor 21 for detecting the rainfall state is input after the waveform shaping circuit 22 shapes the waveform into a rectangular pulse. The processing circuit 15 selectively controls the relays 18 and 19 in response to the inputs from the wiper switch 2 and the raindrop sensor 21 to control the operation of the wiper motor 3.

That is, when the wiper motor 3 is driven continuously 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 supplied from the contacts 24b and 24a of the relay switch 24 to the relay switch 2 of the relay 18.
The power is supplied to the low-speed power input terminal 3a of the wiper motor 3 via the contact points 26a and 26b of the wiper motor 3.

When the wiper motor 3 is driven continuously at high speed, the processing circuit 15 derives a high-level drive signal not only from the output terminal P2 but also from the output terminal P1. As a result, the relay coil 25 of the relay 18 is excited, and the common contact 26a of the relay switch 26 conducts to the individual contact 26c. Therefore, the electric power from the battery 4 via the contacts 24b and 24a of the relay switch 24 from the power supply line 5 is transmitted to the contacts 26a and 26a of the relay switch 26.
The power is supplied to the high-speed power supply input terminal 3b of the wiper motor 3 via 26c.

On the other hand, a cam switch 6 is provided in connection with the wiper motor 3, and the common contact 6a of the cam switch 6 is connected to the ground terminal 3c of the wiper motor 3 when the wiper blade is in the initial position. It is electrically connected to one of the grounded individual contacts 6b. 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 conducted to the other individual contact 6c connected to the power supply line 5. In this manner, the potential of the common contact 6a changes depending on whether the wiper blade is performing 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, once the wiper motor 3 is started, the processing circuit 15 continues to derive a high-level output from the output terminal P2 even if the wiper blade 2 performs the wiping operation and the OFF mode is selected by the wiper switch 2. 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 conducts to the individual contact 6b, and the output terminal P2 of the processing circuit 15 goes low. When the wiper motor 3 is not operated continuously in this state, the relay switch 24
Of the cam switch 6, the contacts 24 c and 24 a of the relay switch 24, and the relay switch 2
6 through the contacts 26a, 26b.
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 driven intermittently, the processing circuit 15 integrates the pulse width of the rectangular wave pulse from the raindrop sensor 21 via the waveform shaping circuit 22. Then, when the integrated value M1 becomes equal to or more than the predetermined threshold value RP, and the counter 27 remains below the predetermined threshold value RP.
The output terminal P2 at the earlier of the time when the intermittent time WOT described later measured by
Outputs a drive signal. Thus, the wiper motor 3 is driven at a wiping interval suitable for a rainy state.

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

[0025]

[Table 1]

Each of the above steps is set based on the time WCT from the end of the previous wiper blade wiping operation until the integrated value M1 becomes equal to or greater than the threshold value RP when the integrated value M1 is equal to or greater than the threshold value RP. Is done. Further, when the integrated value M1 is less than the threshold value RP even after the elapse of the intermittent time WOT, each of the steps is set based on the integrated value M1 at the elapse of the intermittent time WOT.

That is, for example, the intermittent time WOT of 80
% Within the time WUP, the integrated value M1 is equal to the threshold RP
As described above, 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, if the integrated value M1 is less than the value MDN which is の of the threshold value RP at the time when the intermittent time WOT has elapsed, the step of the intermittent time WOT is changed by one step. Such a step change threshold is shown in FIG. Update operation of the intermittent time WOT as described above;
By performing the operation of integrating the output of the raindrop sensor 21, the automatic wiper control is realized.

Power from the battery 4 via the power supply line 5 is supplied to the terminal Vcc of the processing circuit 15 as power for arithmetic processing after being stabilized by the constant voltage circuit 17. The 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 through 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 above, the processing circuit 15 which is also the correction means, in a 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 switched to the INT mode again within a predetermined time T1, for example, three minutes, the LO / INT switching operation is performed twice. It is determined that the wiping operation is being performed at a timing later than the timing at which the operator feels comfortable, and the intermittent time of the seventh step is corrected to be shorter from 24 seconds to 16 seconds. Therefore, a counter 28 for measuring the time T1 is provided in the processing circuit 15.

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

As described above, when the mode is the OFF mode or the HI mode other than the INT mode or the LO mode in steps n2 to n5, in steps n6 to n10, the count value CT, the count value KT of the counter 28, and the 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 to be in the HI mode, the process proceeds to step n11, and it is determined whether or not the mode is selected to be in the LO mode.
It is determined whether or not an INT flag F5 indicating operation in the mode is zero. As a result, the INT flag F
When 5 is zero, that is, when the mode is shifted from the OFF mode or the HI mode to the LO mode, step n2 is executed.
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 the step n2, otherwise proceeds to the step n13.

In step n13, a permission flag F6 indicating that the mode has temporarily shifted from the INT mode to the LO mode is set to 1, and in 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 transitions from the INT mode to the LO mode is added and updated. In Step n16, Step n23,
Within the time T1 measured at n24, the count value C
It is determined whether T has become 2 or more. If not, the process proceeds to step n20. If so, the process proceeds to step n17.

In step n17, the intermittent time WOT
A shortening flag F4 indicating that the seventh step should be shortened
Is set to 1. Thereafter, steps n18 and n19
Then, the count value KT and the permission flag F6 are reset to zero, respectively. Further, after the wiper motor 3 is driven at a low speed in step n20, the process returns to step n2.

When the mode is not the LO mode in step n11, that is, when the mode is the INT mode, the process proceeds to step n21, and the INT flag F5 is set to 1. At step n22, it is determined whether or not the permission flag F6 set at step n13 is zero.
Otherwise, that is, when the mode is temporarily switched from the INT mode to the LO mode and then returned to the INT mode again, the process proceeds to step n23, the counter 28 performs a counting operation, and the count value KT is updated.
In step n24, it is determined whether or not the count value KT has become equal to or longer than the predetermined time T1, and if so, that is, the LO of the wiper switch 2
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, respectively.

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

In step n31, the detection output Ma of the raindrop sensor 21 is added to the integrated value M1, and the integrated value M1 is updated. In step n32, it is determined whether or not the integrated value M1 is equal to or larger than the threshold value RP. And when not,
That is, when the difference 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 a count operation.
At 34, it is determined whether or not the count value WCT is equal to or longer than a predetermined intermittent time WOT. If not, the process returns to step n2.

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

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

In steps n43 and n45, when it is selected that the step of the intermittent time WOT should be maintained or increased, the process proceeds to step n46, and it is determined whether or not the step of the intermittent time WOT has already been set to the seventh step. It is determined, and if so, the routine goes to Step n47. In step n47, it is determined whether or not the shortening flag F4 set in step n17 is set to 1. If so, in step n48, the intermittent time WOT of the seventh step is replaced with the original seventh step. 16 seconds, which is obtained by correcting the value of 24 seconds, is set. When the shortening flag F4 is not 1 in step n47, in step n49, the intermittent time WOT is set to the original value of the seventh step, 24 seconds.

In step n46, when the step of the intermittent time WOT is not the seventh step, and from step n42, the process shifts to step n50, corresponding 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, where the integrated value M1 is set to zero, and further in step n52, the count value WCT is reset to zero. . Thereafter, in step n53, the wiper motor 3 is driven to perform a wiping operation including a high-speed continuous operation, and then the process returns to step n2.

Thus, the wiper control device 1 according to the present invention
In the state where the intermittent time WOT is set to the seventh step, which is the maximum value, when the wiper switch 2 performs the LO / INT switching operation twice from the INT mode within the predetermined time T1, that is, When the operator senses the maximum value of the intermittent time WOT later than the comfortable wiping timing, switches the wiper switch 2 to the LO mode, performs the wiping operation, and then repeats the operation of switching to the INT mode again. The intermittent time in 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 in accordance with the operator's feeling in the case of extremely light rain, such as when traveling in a tunnel without a preceding vehicle, without changing the remaining steps. , And wiper control that matches the operator's feeling can be performed.

When the amount of rainfall is actually extremely small, the intermittent time WOT is changed to the seventh step, which is the maximum value, and the wiper blade can be driven at a proper 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 in the seventh step to perform the initial operation, and the counter 28 indicates the elapsed time after the initial operation. Count.

In the above-described embodiment, a predetermined value of 16 seconds is used as the correction value of the seventh step of the intermittent time WOT. However, as another embodiment of the present invention, the last time of the wiper blade in the INT mode is used. After the wiping operation of
The correction may be made to the time until switching to the O mode. As a result, once the wiper switch 2 is temporarily switched from the INT mode to the LO mode,
When the T mode is selected, the wiping operation can be performed in an intermittent time when the operator feels comfortable.

[0047]

As described above, according to the present invention, in the state where the intermittent time is selected to the maximum value, the driver who is the operator judges that the intermittent time is too long, and once operates the wiper switch. 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,
Only the maximum value of the intermittent time at the time of extremely light rain is corrected to be short, so that the complicated operation of the driver can be reduced, and the wiper blade can be driven at the optimum wiping interval that matches the driver's feeling.

[Brief description of the drawings]

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

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

FIG. 3 is a flowchart illustrating an automatic wiper control operation according to one embodiment of the present invention.

FIG. 4 is a flowchart for explaining an automatic wiper control operation according to one embodiment of the present invention.

[Explanation of symbols]

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

Claims (2)

(57) [Claims] 1. A wiper switch manually operated by an operator to switch an operation state of a wiper blade between at least a continuous operation state and an intermittent operation state at a predetermined intermittent time, and a raindrop sensor for detecting a rainfall state Driving means for reciprocatingly driving a wiper blade for removing raindrops adhered on the surface to be wiped on the surface to be wiped; and when the intermittent operation state is selected by the wiper switch, The value based on the output is integrated, and the integrated value becomes equal to or more than a predetermined threshold within a predetermined intermittent time after the end of the previous wiping operation of the wiper blade, and the intermittent time remains less than the predetermined threshold. Control means for outputting a drive signal indicating that the wiper blade should be driven to the drive means at the earlier time point of the elapsed time point In response to the operation of the wiper switch, in the state where the intermittent time of the control means is selected to the maximum value, after the operation state is once switched to the continuous operation state, and then returned to the intermittent operation state again, And a correcting means for shortening the maximum value of the intermittent time. 2. The correction means sets the maximum value of the intermittent time to a time from the end of the previous wiping operation of the wiper blade to a time when the wiper blade is switched to a continuous operation state, and corrects the maximum value. The wiper control device according to claim 1, wherein: