JPH0524513A - Wiper control device - Google Patents

Abstract

PURPOSE:To add an automatic wiper function which is capable of sensing adjustment without newly adding an exclusive switch or a volume switch to a wiper control device where a wiper switch which is capable of selecting the activation mode of an intermittent activation, a low speed continuous activation, a high speed continuous activation, or the like is provided. CONSTITUTION:A control device 3 is interposed between a switch circuit 1 capable of selection of the respective activation modes and a wiper motor 2, and the control device 3 outputs the inspection pulse to a wiper switch 11. On the basis of the output voltage of the wiper switch 11 in response to the inspection pulse, the wiper switch 11 reads whether or not the wiper switch 11 is selected to the INT mode, and reads the resistance of a variable resistor R1a which is provided in order to change the intermittent time. Thus, an automatic wiper function capable of sensing adjustment is added without further providing any exclusive switch or volume switch to the wiper control device without automatic wiper function.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a so-called automatic wiper control device for controlling a wiper operation in response to a rainfall condition, and more specifically, for adding an automatic wiper function to a wiper control device having no automatic wiper function. Regarding the configuration of.

[0002]

2. Description of the Related Art In an existing wiper control device having no automatic wiper function, in order to downsize the device, a wiper switch for selecting an operation mode of the wiper and a wiper operation is performed according to a setting state of the switch. And a control circuit for controlling the control circuit are arranged on one printed circuit board and are integrally formed.

In order to newly add an automatic wiper function to this wiper control device, it is detected that the wiper switch is set to the intermittent mode, and the rain condition is detected based on the output of the raindrop sensor. It is necessary to calculate a corresponding intermittent time and add a new control circuit for controlling the wiper operation.

However, when the existing control circuit and the wiper switch are integrated as described above, it is difficult to detect the setting state of the wiper switch from the outside. For this reason, in a typical conventional technique, a dedicated switch for the operation of the auto wiper is separately added when adding a configuration for controlling the auto wiper.

[0005]

Therefore, in the above-mentioned conventional technique, it is necessary to operate the dedicated switch of the newly added auto wiper in order to perform the auto wiper operation. Therefore, the existing wiper switch and the new exclusive switch for the auto wiper are located at different positions, which easily causes confusion and is inferior in operability.

Also, in order to add a dedicated switch for the auto wiper, it is necessary to modify the vicinity of the added location, and there is an aesthetic problem that the dedicated switch for the added auto wiper and the shape of the existing wiper switch are not balanced. Also occurs.

Furthermore, by providing a switch for such an auto wiper and a sensitivity adjusting volume or the like for setting the raindrop detection sensitivity of the auto wiper control device to a different desired value for each driver, Furthermore, it is not balanced, and operability and aesthetic problems arise.

An object of the present invention is to provide a wiper control device which can add an automatic wiper function without adding a dedicated switch or the like.

[0009]

According to the present invention, there are provided a driving means for driving a wiper blade to reciprocate on a surface to be wiped, a first operation mode for continuously driving the wiper blade, and a second operation mode for intermittent driving. A switching means for selecting, and a changing means for changing the intermittent time at the intermittent driving in association with the switching means, and responding to a switching state of the switching means and a set value of the changing means. In the wiper control device including the first control means for controlling the drive means, the raindrop sensor is interposed between the drive means and the first control means, and an identification signal is sent to the switching means and the changing means. The operating mode selected by the switching means and the set value of the changing means are output from the output voltage level of the first control means that outputs and responds to the identification signal. A detection means for output, a wiper control apparatus characterized by in response providing a second control means for driving said drive means to the detection result and the detection result of the raindrop sensor of the detection means.

[0010]

According to the present invention, the first control means is provided with the switching means for selecting the operation mode. When the first operation mode is selected by the switching means, the switching means is provided through the drive means. The wiper blade is continuously driven, and when the second operation mode is selected, the wiper blade is intermittently driven. The first control means is also provided with a changing means, which is constituted by a volume or the like, in association with the switching means, and responds to the change in the set value of the volume by intermittently driving in the second operation mode. Intermittent time is, for example, 1.5 to 2
It is changed in the range of 0 seconds. In the existing wiper control device configured as described above, the second control means according to the present invention is interposed between the first control means and the drive means.

The first control means is provided with a plurality of contacts for switching the switching states corresponding to the first and second operation modes, and the detection means of the second control means is the first control means. An identification signal, an inspection pulse, etc. are derived to the means. The detection means detects the switching state or volume setting value of the first control means based on the level change of the inspection pulse due to the impedance change in the first control means corresponding to the switching state or volume setting value.

As a result of this detection, when the first control means is selected in the second operation mode, the second control means, for example, has a sensitivity corresponding to the volume set value, and the level of the integrated value based on the output of the raindrop sensor. Discrimination is performed, and when the discrimination level is reached or higher, the wiper blade is driven. Therefore,
It is possible to perform the wiping operation corresponding to the rainfall condition with the operator's favorite sensitivity.

In this way, the switching state of the wiper switch can be detected and the automatic wiper operation can be realized without newly adding an exclusive switch for the auto wiper to the existing wiper switch. Further, for the sensitivity adjustment, it is possible to use an existing volume adjustment intermittent volume control, and there is no need to additionally install a volume adjustment volume adjustment or the like.

[0014]

1 is a block diagram showing the electrical construction of an embodiment of the present invention. Between the existing switch circuit 1 which is the first control means and the wiper motor 2 which is the drive means,
When the wiper switch 11 is set to the INT mode which is the intermittent mode by interposing the control device 3 which is the second control means, the wiper blade is driven at the wiping interval corresponding to the rainfall state detected by the raindrop sensor 4, Auto wiper operation is realized.

Therefore, in the existing wiper control device, in the wiper motor 2, the terminal + 1d connected to the low speed power supply input terminal P1 of the motor 21 is connected to the terminal + 1a of the switch circuit 1 and the high speed power supply input terminal P2. The connected terminal + 2d is connected to the terminal + 2a of the switch circuit 1, and the terminal + Sd connected to the common contact S2a of the cam switch 22 is connected to the terminal + Sa of the switch circuit 1.

The switch circuit 1 includes a wiper switch 11
And a circuit connected to the wiper switch 11 are formed on one printed circuit board.
Corresponding to the setting mode of the terminals + Sa, + 2a, + 1a
The electric potential of each changes. The terminal + Ba is supplied with electric power from the battery 6 via the ignition key switch 5, and the terminal Ga is grounded.

The wiper switch 11 has an OFF, IN
Four operating modes can be set: T, LO and HI. When set to the OFF mode, the wiper operation is suspended. When the INT mode, which is the second operation mode, is set, the wiper blade is driven at the wiping interval corresponding to the rainfall state. When the LO mode and the HI mode, which are the first operation modes, are set, the wiper blade is continuously driven, and is driven at a low speed in the LO mode and at a high speed in the HI mode.

In FIG. 1, the wiper switch 11 is
The contact connection state in each of the operation modes is shown, that is, in the OFF mode, the contacts +1 and + S are in conduction, the contacts INT1 and B1 are in conduction, and IN
In the T mode, the contacts +1 and + S are conductive, and the contacts INT1 and INT2 are conductive, and in the LO mode, the contact + is +.
B and +1 conduct, and in the HI mode, contacts + B and +2 conduct.

When the wiper switch 11 is set to the OFF mode, the constant voltage circuit 30 in the control device 3 is connected to the terminal + 1b-terminal + 1a-contact + 1-contact + S-contact S1a-contact S1c-terminal + Sa-terminal. The voltage IG of the battery 6 is applied via the ignition key switch 5 via + Sb-resistor R2-resistor R1-terminal + Bb. In this state, a control circuit for performing automatic wiper control by limiting the current of the resistors R1 and R2. 31 is not supplied with sufficient power to energize 31 and therefore control circuit 3
1 becomes a dormant state.

In the OFF mode, the voltage IG is applied to one terminal of the capacitor C1 via the resistors R1 and R2 as described above. The other terminal has a variable resistor R1a and a resistor R1b for setting an intermittent time.
And a resistor R1e connected in parallel to these resistors R1a and R1b and having a resistance value smaller than the combined resistance value in the state where the resistors R1a and R1b are connected in series, the terminal + B
The voltage IG is applied from a. Therefore, the capacitor C1 is discharged.

Therefore, when the wiper switch 11 is set to the INT mode, the capacitor C1a is charged through the contact INT1-contact INT2-diode D1-resistor R1c, and the capacitor C1a is fully charged and the terminal voltage is preset. When the value exceeds the specified value, the transistor Tr1
Conducts.

As a result, the relay coil L1 is excited, the relay switch S1 is switched, and the terminal + Ba-contact S1b-contact S1a-contact + S-contact + 1-terminal + 1a.
The voltage I is applied to the constant voltage circuit 30 through the terminal + 1b.
G is supplied. When the control circuit 31 is energized in this manner, the wiper switch 11 is controlled as described later.
In the INT mode, the automatic wiper control operation is performed based on the output from the raindrop sensor 4 via the waveform shaping circuit 34.

The resistance R1e is set to O as described above.
In the FF mode, they are connected in parallel to the resistors R1b and R1a to reduce the time constant for charging the capacitor C1. Therefore, the contact mode of the wiper switch 11 is INT-
Even if the capacitor C1 is once discharged as in the case of being switched to OFF-INT, it can be rapidly charged,
As a result, the control circuit 31 can be quickly started up.

The output of the control circuit 31 during the automatic wiper operation is led to the relay coils L3 and L4 via the diodes D3a and D4a, respectively. That is, when the low speed wiper is driven, the relay coil L3 is excited and the relay coil L4 is demagnetized. As a result, the electric power from the battery 6 is supplied to the low speed power supply input terminal P1 of the motor 21 through the terminal + Bb-contact S3b-contact S3a-contact S4a-contact S4c-terminal + 1c-terminal + 1d.
When the high speed wiper is driven, the relay coils L3 and L4 are both excited, and the high speed power input terminal P2 of the motor 21 is excited.
Is powered. Furthermore, during intermittent driving, both relay coils L3 and L4 are demagnetized.

When the wiper switch 11 is set to the LO mode, the voltage IG is supplied to the constant voltage circuit 30 as follows: terminal + Ba-contact + B-contact + 1-terminal + 1a-terminal +1.
supplied via b. As a result, the control circuit 31 is energized to detect the switching state of the wiper switch 11 as will be described later, and when in the LO mode, excites the relay coil L3 so as to continuously drive the motor 21 at a low speed. Hold in the state.

When the wiper switch 11 is set to the HI mode, no electric power is supplied to the constant voltage circuit 30, and the control circuit 31 is in the idle state. However, the terminal + Ba-
Contact + B-contact + 2-terminal + 2a-terminal + 2b-relay coils L3, L4 via diodes D3b, D4b
Is supplied with electric power and is excited, and the electric power from the battery 6 is the terminal + Bb-contact S3b-contact S3a-contact S4a.
It is supplied to the high-speed power supply input terminal P2 of the motor 21 via the-contact S4b-terminal + 2c-terminal + 2d.

The wiper motor 2 has a motor 21 and a cam switch 22 which are integrally formed.
The cam 23 rotates according to the wiping position of the wiper blade. Motor 21 with wiper blade in rest position
, The common contact S2a of the cam switch 22 is electrically connected to the individual contact S2c, so that the control device 3
+ Sc is the terminal + Sd-contact S2a-contact S2c
Is connected to a terminal Gd which is connected to the ground terminal PG of the motor 21 and is set to the ground potential. When the cam switch 22 rotates, for example, 30 degrees or more, the common contact S2a
Conducts to the individual contact S2b, and therefore the terminal + Sd
From the voltage IG of the battery 6 supplied to the terminal + Bd
Is derived.

In the INT mode and the LO mode, the potential of the terminal + Sc of the control device 3 is read into the control circuit 31 via the processing circuit 32, and the control circuit 31
Continues to excite the relay coil L3 during the wiping operation of the wiper blade to return the wiper blade to the rest position.

Further, the wiper switch 11 is turned off during the wiping operation in which the wiper blade is away from the rest position.
When switched to the mode, the power supply to the control circuit 31 is cut off in the INT mode and the LO mode, so that the supply of the exciting current to the relay coil L3 through the diode D3a is stopped, and in the HI mode, the diode D3b, Relay coil L via D4b
The supply of the exciting current to L3 and L4 is stopped, whereby the common contact S3a of the relay switch S3 becomes the individual contact S3c.
And the common contact S4a of the relay switch S4 conducts to the individual contact S4c, and thus the power supply to the low speed power input terminal P1 of the motor 21 is continued until the wiper blade returns to the rest position.

As described above, the wiper switch 11 is set to LO.
Mode and INT mode are set,
The control circuit 31 is energized via the constant voltage circuit 30,
Therefore, the control circuit 31 detects the switching state of the wiper switch 11 and the set value of the variable resistor R1a as follows, and performs the auto wiper control operation corresponding to the set value in the INT mode, and in the LO mode. The motor 21 is continuously driven at a low speed.

FIG. 2 shows the switch circuit 1 when the wiper switch 11 is set to the INT mode or the LO mode.
It is a circuit diagram for explaining the connection state inside. A low-level pulse having a pulse width of 2 msec and a pulse interval of 200 msec, for example, as shown in FIG. 3A is derived from the control circuit 31, and the pulse is generated by the pulse generation circuit 33 realized by a transistor or the like in FIG. After being inverted as shown in 2), it is derived from the terminal + Sb as a check pulse as an identification signal via the resistor R2. This inspection pulse is applied to the contacts INT1 and I of the wiper switch 11.
When conducting with NT2, the diode D
1, and is shunted to the drive circuit 18 including the resistors R1c and R1d and the transistor Tr1.

In other words, in terms of alternating current, when the LO mode is set, the pulse from the pulse generating circuit 33 has a resistance R2 and a resistance R2 as shown in FIG. 4 (1).
The voltage is divided by 1b and R1a and appears at the terminal + Sb. Further, when the INT mode is set, as shown in FIG. 4B, the voltage is divided by the resistor R2, the resistors R1b and R1a and the combined impedance of the drive circuit 18, and appears at the terminal + Sb.

Therefore, for example, when the resistance value of the variable resistor R1a is minimum, the peak value VL in the INT mode becomes a small value, for example, 1 V, as shown in FIG. 3 (3). On the other hand, the peak value VH in LO mode is shown in FIG.
As shown in (4), it becomes a high value, for example, 3V.
Further, by increasing the resistance value of the variable resistor R1a, the crest value VM fluctuates between the crest values VL and VH as indicated by the broken line in FIG. 3 (4).

These crest values VL, VM, VH are set as reference voltages VTH1, V predetermined by the level discrimination circuit 35.
The setting mode of the wiper switch 11 and the setting value of the variable resistor R1a can be read by comparing with TH2. That is, the level discrimination circuit 35 includes, for example, a voltage dividing circuit, a comparator, and a reference voltage source.
In the voltage dividing circuit, the input voltage is divided into, for example, 1/2, the reference voltage VTH1 is set to 1.5V, and the reference voltage VTH2 is set to 2V.

Therefore, the level discrimination circuit 35 can detect whether the wiper switch 11 is selected in the LO mode or the INT mode and whether the resistance value of the variable resistor R1a is high or low. The variable resistor R1
Originally, a is for setting the charging time constant of the capacitor C1. Therefore, the smaller the resistance value, the faster the capacitor C1 is charged and the shorter the intermittent time becomes. Therefore, the control circuit 31 sets the control sensitivity to be described later to be higher as the resistance value of the variable resistor R1a is smaller, that is, the crest value VM is lower.

During the automatic wiper control in which the wiper switch 11 is selected in the INT mode, the control circuit 31 integrates the pulse widths of the rectangular wave pulses from the raindrop sensor 4 via the waveform shaping circuit 34, and the integrated value M1 is predetermined. The relay coils L3 and L4 are selectively excited at a time point which is the threshold value RP or more and a time point when an intermittent time WOT, which will be described later, measured by the counter 40 has elapsed, whichever is earlier. In this way, the wiper motor 2 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 2 is in the high speed continuous operation state, when the second step is selected, the wiper motor 2 is in the low speed continuous operation state, and when the third step is selected, it is 1.5 seconds. It is set to the intermittent operation state, and then 4 seconds for 3 seconds and 5 steps for 6 seconds.
Seconds, 12 seconds for the 6th step, 24 for the longest 7th step
It is set to the intermittent operation state for seconds.

[0038]

[Table 1]

When the integrated value M1 is equal to or greater 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, if the integrated value M1 is less than the threshold value RP even after the intermittent time WOT has elapsed, it is 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
When the integrated value M1 becomes equal to or more than the threshold value RP within the time WUP that is%, the step of the intermittent time WOT is set to be shortened 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 4.

FIG. 6 is a flow chart for explaining the wiper control operation. When the wiper switch 11 is selected to the INT mode or the LO mode, the control device 3 is energized to start the operation shown in FIG. 6 as described above. In step n1, flags F1 to F3 described later are provided.
Initialization processing of the integrated value M1 and the count value WCT is performed. In step n2, the pulse generation circuit 33 outputs an inspection pulse.

At step n3, when the discrimination result in the level discrimination circuit 35 indicates the LO mode, that is, the peak value V1 input to the level discrimination circuit 35 is the threshold value V.
When it is equal to or more than TH2, the process proceeds to step n4, the relay coil L3 is excited and the wiper blade is driven, and then the process returns to step n2.

In step n3, when the peak value V1 is less than the threshold value VTH2, it is determined in step n5 whether or not it is more than the threshold value VTH1, and if so, the threshold value RP is set to the first value RP1 in step n6. Is set to 0, otherwise the value R
It is set to a value RP2 smaller than P1.

When the threshold value RP is set in step n6 or n7, the process proceeds to step n11, the detection output Ma of the raindrop sensor 4 is added to the integrated value M1, the integrated value M1 is updated, and the integrated value M1 is calculated in step n12. The value M1 is the threshold R
It is determined whether or not P or more. If not, that is, if it is less than the threshold value RP, the process proceeds to step n13. At step n13, the count value W of the counter 40
CT is added, the counting operation is performed, and step n1
In 4, the count value WCT has a predetermined intermittent time WO
It is determined whether or not it is equal to or more than T, and if not, the process returns to step n2.

In step n12, the integrated value M1
Is greater than or equal to the threshold value RP, the process proceeds to step n21,
The count value WCT of the counter 40 is 8 of the intermittent time WOT.
It is determined whether the time WUP is 0% or less, and if so, the process moves to step n22, and the flag F1 for reducing the step of the intermittent time WOT is set to 1 and the step is held. Both the flag F2 for starting and the flag F3 for rising are 0.
Is reset to.

When the count value WCT exceeds the time WUP in step n21, the process proceeds to step n23, where the flag F2 is set to 1 and both flags F1 and F3 are reset to 0.
Furthermore, in step n14, the count value WCT
Is over the intermittent time WOT, step n24
Then, it is determined whether or not the integrated value M1 at that time is less than the value MDN which is 1/2 of the threshold value RP. If not, the process proceeds to step n23 and the step is held, and if so, the step The flag F in n25
3 is set to 1 and flags F1 and F2 are set to 0
Is reset to.

Thus, steps n22, n23, n25
When it is selected that the step of the intermittent time WOT is to be retained or changed, the process proceeds to step n26, and the next intermittent time WOT corresponding to the set flags F1 to F3.
Is set.

When the next intermittent time WOT is set,
The integrated value M1 is reset to 0 in step n31, and the count value WCT is reset to 0 in step n32. After that, in step n33, the wiper motor 2 is driven to perform the wiping operation including the high-speed continuous operation, and then the process returns to step n2.

As described above, in the wiper control device according to the present invention, the control device 3 for adding the automatic wiper function is provided between the existing switch circuit 1 and the wiper motor 2, and the control device 3 has the switch circuit 1. The setting mode of the wiper switch 11 therein can be detected. Therefore, it is not necessary to provide a dedicated switch for the auto wiper separately from the existing wiper switch 11.

Further, the control circuit 31 can read the set value of the variable resistor R1a. Therefore, it is not necessary to separately provide a volume for sensitivity adjustment, and the wiper sensitivity desired by the operator can be set by using the variable resistor R1a for adjusting the existing intermittent time.

As described above, by using the existing switch and variable resistor, the operation is not confused, and no modification or the like due to the addition of the switch or variable resistor is required, so that the mounting work can be simplified. You can do it, and it will not spoil your aesthetics. Furthermore, the existing wiper switch 11 and the variable resistor R1a are in positions where they can be easily operated, and good operability can be maintained.

Furthermore, since the control circuit 31 for performing the auto wiper control operation is energized only when the wiper switch 11 is in the INT mode and the LO mode,
In the OFF mode and the HI mode, the control circuit 31 is put in a rest state, and when the control circuit 31 is out of control or when the raindrop sensor 4 is operating.
It is possible to secure a fail-safe function in case of malfunction due to adhesion of dirt to the.

The threshold value for sensitivity adjustment is not limited to one VTH1 as in the above-described embodiment, but a plurality of threshold values may be provided. Further, the sensitivity adjustment may be realized by changing the intermittent time WOT instead of selecting the threshold value RP as described above.

[0054]

As described above, according to the present invention, the second control means for performing the automatic wiper control is interposed between the first control means and the drive means of the wiper control device not having the automatic wiper function. The second control means derives an identification signal, an inspection pulse, or the like to the first control means, and detects the switching state of the contact for switching the operation mode and the set value of the volume for setting the intermittent time.

Thus, the auto wiper function can be added by using the existing switch or volume without adding a dedicated switch for the auto wiper and a volume for sensitivity adjustment. Therefore, the appearance is not deteriorated and the operation is not confused.

[Brief description of drawings]

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

FIG. 2 shows the wiper switch 11 in the INT mode or the LO mode.
It is a circuit diagram for explaining the connection state in the switch circuit 1 when the mode is set.

FIG. 3 is a waveform diagram for explaining a setting mode of the wiper switch 11 and an inspection operation for reading the resistance value of the variable resistor R1a.

FIG. 4 is an equivalent circuit diagram when a test pulse is applied to the switch circuit 1.

FIG. 5 is a diagram showing a threshold value for changing the step of the intermittent time WOT.

FIG. 6 is a flowchart for explaining a wiper control operation.

[Explanation of symbols]

 1 Switch Circuit 2 Wiper Motor 3 Controller 4 Rain Drop Sensor 11 Wiper Switch 22 Cam Switch 31 Control Circuit 32 Processing Circuit 33 Pulse Generation Circuit 35 Level Discrimination Circuit

Claims (1)

Claim: What is claimed is: 1. A drive unit that drives the wiper blade to reciprocate on the surface to be wiped, and a first operation mode that continuously drives the wiper blade.
A switching means for selecting a second operation mode for intermittent driving is provided, and a changing means for changing the intermittent time during the intermittent driving is provided in association with the switching means. The switching state of the switching means and the change A wiper control device including first control means for controlling the drive means in response to a set value of the means, wherein the raindrop sensor is interposed between the drive means and the first control means, and the switching means is provided. And a detection means for outputting an identification signal to the changing means and detecting the operation mode selected by the switching means and the set value of the changing means from the output voltage level of the first control means in response to the identification signal. And a wiper characterized by including second control means for driving the drive means in response to the detection result of the detection means and the detection result of the raindrop sensor. Control device.