JPS6325253Y2 - - Google Patents

Description

[Detailed description of the invention] The invention provides a wiper motor that operates in conjunction with the operation of the washer switch.
This invention relates to an improvement in a washer/wiper interlocking device that operates for a predetermined period of time even after being turned off.

2. Description of the Related Art Conventionally, there is a device shown in FIG. 1, for example, which operates a wiper motor in conjunction with the operation of a washer switch.

When the washer switch SW is turned on, the washer motor 1 operates, and at the same time, the amplifier circuit section 3 is driven after the charging time of the time limit circuit section 2, which is composed of a capacitor _C1 and a resistor _R1 , has elapsed. When transistors Tr ₁ and Tr ₂ constituting the amplifier circuit section 3 are turned on, the relay 4 is activated and the wiper motor 5 starts operating. 6 is a wiper motor automatic stop switch, and a movable contact 6a is at a predetermined wiper stop position, and when the wiper motor 5 starts operating thereafter, the movable contact 6a operates to change over the switch contact. 7 is the power supply, 8
is the ignition switch.

However, in the washer and wiper interlocking device configured as described above, the wiper operating time changes with fluctuations in the voltage of the power source 7, and the wiper motor 5
operates based on a time chart in which the horizontal axis in FIG. 2 is time T. That is, the watch switch
When the SW is turned on, the potential Ea at point A in the timer circuit section 2 gradually decreases from the potential Eo at the power source 7 as the capacitor _C1 is charged.
In this case, when the voltage of the power source 7 changes, the drop characteristic of the potential Ea at the point A also changes. This is represented by a potential curve Vl at low voltage and a potential curve Vh at high voltage. Eth indicates the potential at point A when the first transistor Tr ₁ is switched. Also, when the watch switch SW is turned OFF, the potential at point A, Ea, will change as the capacitor _C1 discharges.
The potential curves Vl and Vh gradually increase. Therefore, in relation to the operating time of the washer switch SW, the operating time of the first transistor _Tr1 , in other words, the operating time of the wiper motor 5 is as follows. The operation of the first transistor Tr ₁ when the voltage of the power supply 7 is low is as shown in (Tr ₁ ) in Fig. 2.
Turn on the watch switch SW as shown in L,
When the potential Ea at point A drops to the potential Eth on the potential curve Vl, it turns ON and the watch switch is turned on.
When the SW is turned OFF and the potential Ea at point A increases to the potential Eth on the potential curve Vl, it is turned OFF. At this time, the delay time from turning off the watch switch SW to turning off the first transistor _Tr1 is _T1 . Next, the operation of the first transistor Tr ₁ when the voltage of the power supply 7 is high is as shown in (Tr ₁ )h in Figure 2, by turning on the watch switch SW and increasing the voltage at point A.
When Ea decreases to the potential Eth on the potential curve Vh, it turns ON and the watch switch SW is turned on.
When it is turned off and the potential Ea at point A increases to the potential Eth on the potential curve Vh, it is turned off. At this time, the delay time from turning off the watch switch SW to turning off the first transistor _Tr1 is _T2 . The higher the voltage of the power supply 7 is, the longer the delay times T ₁ and T ₂ become, causing the following problems. In general, as shown in the wiper operating characteristic diagram in which the vertical axis is time To in FIG. 3, the higher the voltage Eo of the power source 7, the shorter the wiper operating characteristic. In addition, in the figure, N ₁
N2 shows a characteristic curve of one reciprocating operation of the wiper, _N2 shows a characteristic curve of two reciprocating operations, and _N3 shows a characteristic curve of three reciprocating operations, and these curves are proportional to the number of rotations of the wiper motor 5. Also, Ta is the watch with the above configuration,
Washer switch in wiper interlocking device
The delay time characteristics from when the SW is turned off until the first transistor Tr ₁ is turned off are shown. Therefore, if the voltage of the power supply 7 is low, turn off the watch switch SW.
Since the windshield surface is wiped by the wiper (not shown) approximately once until the rear wiper motor 5 stops, the washer liquid sprayed on the windshield surface is not wiped off sufficiently. In the case of high voltage, the wiping operation is performed approximately four times, which is bothersome to the driver.

The present invention was devised in view of the above-mentioned problems, and its purpose is to compare the output voltage of a time limit circuit section having a constant voltage circuit with the reference voltage of a reference voltage generation circuit section. It is equipped with a circuit section that controls the rotational characteristics of the wiper motor 5 and the watch switch.
By making the delay time characteristics until the wiper motor 5 stops after being turned off substantially the same, the number of wiper wiping operations after the washer switch is stopped can be made substantially the same even if the power supply voltage fluctuates.

DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the washer/wiper interlocking operating device according to the present invention will be described in detail with reference to the accompanying drawings.

The configuration will be explained based on Fig. 4. In the figure, SW,
1, 5, 6, 7 and 8 are the same as those in the conventional example shown in FIG. 1, and their explanation will be omitted.

Reference numeral 9 denotes a time limit circuit section, which is composed of a capacitor C ₂ , a constant voltage Zener diode D ₁ , resistors R ₂ , R ₃ , R ₄ and a backflow prevention diode D ₂ . Capacitor C ₂ has one end connected to the positive terminal of power supply 7,
The other end is grounded via a resistor R ₂ , a diode D ₂ and a watch switch SW to form a charging circuit. A Zener diode _D1 is connected in parallel to both sides of the capacitor _C2 to form a constant voltage circuit for the charging circuit. Note that this constant voltage circuit may be constructed of other components such as a varistor. Furthermore, a resistor R ₃ is connected in parallel to both ends of the capacitor C ₂ . One side of the washer motor 1 is connected to the connection point between the diode _D2 and the washer switch SW.

Reference numeral 10 denotes a reference voltage generation circuit, which is composed of resistors R ₅ and R ₆ that divide the voltage of the power supply 7. resistance
One end of _R5 is connected to the positive electrode of the power source 7, and the other end is connected to one side of the resistor _R6 . The other end of resistor _R6 is grounded.

A comparison circuit section 11 compares the output voltage of the timer circuit section 9 with the reference voltage of the reference voltage generator 10, and is composed of a PNP type first transistor Tr ₃ and resistors R ₇ and R ₈ . The first transistor Tr ₃ connects its base to the capacitor via the resistor R ₄ .
It is connected to point B where C ₂ and resistor R ₂ are connected, the emitter is connected to the connection point of resistor R ₅ and resistor R ₆ , and the collector is grounded via resistors R ₇ and R ₈ .

Reference numeral 12 denotes an amplifier circuit section, which is composed of an NPN type second transistor Tr ₄ , a relay 13 , and a diode D ₃ for preventing a surge caused by the back electromotive force of the relay 13 . The second transistor Tr ₄ has its base connected to the connection point between the resistors R ₇ and R ₈ , its emitter grounded, and its collector connected to the positive electrode of the power source 7 via the coil 13 a of the relay 13 . A diode _D3 is connected in parallel to both sides of the coil 13a. The relay 13 has fixed contacts 13b and 13c.
and a movable contact 13d, which is attracted to the fixed contact 1 when the coil 13a is magnetized.
3b to the fixed contact 13c.
In the relay 13, the fixed contact 13c is grounded,
The movable contact 13d is connected to one side of the wiper motor 5.

The wiper motor automatic stop switch 6 connects its movable contact 6a to the fixed contact 13b of the relay 13,
While connecting the fixed contact 6b to the positive electrode of the power source 7,
The fixed contact 6c is grounded. The other of the washer motor 1 and wiper motor 5 is connected to the positive electrode.

Next, the operation will be explained.

When the washer switch SW is OFF, the washer motor 5 does not operate, and the timer circuit 9 does not operate.
It is OFF, and each transistor Tr ₃ and Tr ₄ is OFF. Therefore, the coil 13a of the relay 13 is in a non-excited state, the movable contact 13d is in contact with the fixed contact 13b, and the wiper motor 5 is not operated. Furthermore, when the wiper motor 5 is not operating, the movable contact 6a of the wiper motor automatic stop switch 6 is in contact with the fixed contact 6b.

Now, when the watch switch SW is turned on, the watch motor 1 starts operating, and the capacitor C ₂ is energized via the resistor R ₂ , the diode D ₂ and the watch switch SW to start charging. Charging of capacitor _C2 progresses, and the potential at point B Eb
The charging time elapses until the voltage drops to the sum of the divided potential by resistors _R5 and _R6 , the conduction potential between the emitter and base of the first transistor _Tr3 , and the potential across both sides of resistor _R4 . After that, the first transistor Tr ₃ is turned on, and the second transistor Tr ₄ is also turned on.
Turns on. Then, the coil 13a of the relay 13
is excited, the movable contact 13d switches from the fixed contact 13b to the fixed contact 13c, and the wiper motor 5 starts operating.

Thereafter, when the washer switch SW is turned OFF, _the washer motor 1 stops and the charging circuit to the capacitor _C2 is _briefly cut off. It is gradually discharged through a discharge circuit composed of a resistor R ₅ , a first transistor Tr ₃ , and a resistor R ₄ . The discharge of capacitor C ₂ progresses, and the potential Eb at point B changes to the resistance R ₅
and the divided potential by the resistor _R6 , the conduction potential between the emitter and the base of the first transistor _Tr3 , and the resistor
After the discharge time has elapsed until the potential increases to the sum of the potential across _R4 , the first transistor _Tr3
is turned OFF, and the second transistor Tr ₄ is also turned OFF. Accordingly, the coil 13a of the relay 13 becomes de-energized and the movable contact 13d also returns to its original state, so that the wiper motor 5 automatically stops after the wiper motor automatic stop switch 6 returns to its initial position.

In this case, changes in the operating time of the first transistor Tr ₃ , that is, the operating time of the wiper motor 5 due to fluctuations in the voltage of the power source 7 will be explained based on a time chart in which the horizontal axis of FIG. 5 is the time T.

When the watch switch SW is turned on, the potential Eb at point B in the timer circuit 9 gradually decreases from the potential Eo of the power source 7 as the capacitor _C2 is charged.

In this case, when the voltage Eo of the power source 7 changes, the drop characteristic of the potential Eb at point B also changes, which is represented by a potential curve Vlo at low voltage and a potential curve Vho at high voltage, respectively. The potential at point B during switching of the first transistor Tr ₁ is (Eth)L when the voltage of the power supply 7 is low, and (Eth)H when the voltage of the power supply 7 is high.
Each is represented by . Also, the charging voltage of capacitor _C2 is limited by Zener diode _D1 ,
The potential Eb at point B at maximum charging becomes Ed. after that,
When the watch switch SW is turned OFF, the potential Eb at point B changes from the potential curve as capacitor _C2 discharges.
It will gradually increase like Vo. Therefore,
In relation to the operating time of the watch switch SW, the operating time of the first transistor _Tr1 , in other words, the operating time of the wiper motor 5 is as follows. The operation of the first transistor Tr ₃ when the voltage of the power supply 7 is low is to turn on the watch switch SW and change the potential Eb at point B to the potential (Eth)L on the potential curve Vlo.
When the voltage drops to 0, the watch switch SW is turned OFF and the above B point potential Eb becomes the potential curve Vo.
When the potential (Eth) at the top increases to L, it turns OFF. At this time, the delay time from turning off the watch switch SW to turning off the first transistor _Tr3 is _T3 . This state is shown in (Tr ₃ )L in FIG. Next, when the voltage of the power supply 7 is high, the operation of the first transistor Tr ₃ is determined by pressing the watch switch SW.
When the B point potential Eb drops to the potential (Eth)H on the potential curve Vho, it turns ON, and the watcher switch SW is turned OFF so that the B point potential Eb changes to the potential (Eth)H on the potential curve Vo. When it increases to , it turns OFF. The watch switch at this time
The delay time from when the SW is turned on until the first transistor Tr ₃ turns off is T ₄ . This state is shown in (Tr ₃ )H in FIG. Therefore, this delay time T ₃ and
T ₄ becomes shorter as the voltage of the power source 7 becomes higher. This is shown in Fig. 3. The delay time characteristic from turning off the watch switch SW to turning off the first transistor Tr ₃ is indicated by Tb in Fig. 3, and the characteristic curves of wiper reciprocating operation N ₁ , N ₂ and has approximately the same slope as N ₃ . This delay time characteristic is determined by the time constant of the time limit circuit section 9, the voltage characteristic of the Zener diode _D1 , etc.
After the vehicle is turned off, the washer fluid sprayed onto the windshield surface will be thoroughly wiped off, and the decision will be made so as not to cause any inconvenience to the driver. In the present invention, taking these into consideration, the windshield surface is wiped by the wiper approximately 2 to 3 times after the washer switch SW is turned off until the wiper motor 5 is stopped.

The present invention has the above configuration and operation, and has the following effects.

In other words, it is equipped with a comparator circuit that compares the output voltage of a time limit circuit section with a constant voltage circuit and the reference voltage of a reference voltage generation circuit, and is equipped with a comparison circuit that compares the output voltage of a time limit circuit section with a constant voltage circuit and the reference voltage of a reference voltage generation circuit, and calculates the rotation characteristics of the wiper motor and the delay time characteristics from when the watch switch is turned off until the wiper motor stops. By making them almost the same,
Even if the power supply voltage fluctuates, the number of times the wiper wipes after the washer switch is stopped can be kept almost the same, making it possible to wipe off the washer liquid sprayed on the windshield in a rational and sufficient manner. . Also, even when the power supply voltage is high,
The number of times the wiper wipes after the washer switch is turned off is the minimum necessary and does not cause any inconvenience to the driver.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram showing a conventional washer and wiper interlocking operation device, Fig. 2 is a time chart in Fig. 1, Fig. 3 is a wiper operation characteristic diagram, and Fig. 4 is a washer and wiper interlocking operation according to the present invention. FIG. 5 is a circuit diagram showing one embodiment of the device, and is a time chart in FIG. 4. 1... Washer motor, 5... Wiper motor, 9... Time limit circuit section, 10... Reference voltage generation circuit section, 11... Comparison circuit section, 12... Amplifier circuit section, SW... Watcher switch, D ₁ ...Zener diode.

Claims (1)

[Scope of utility model registration request] A washer and wiper interlocking operating device comprising a washer switch that operates a washer motor, an amplifier circuit that operates a wiper motor, and a timer circuit that outputs an output to the amplifier circuit in order to operate the wiper motor for a predetermined period of time. , the time limit circuit section includes a capacitor forming a charge/discharge circuit and a constant voltage circuit connected in parallel to the capacitor, a reference voltage generation circuit section that divides the power supply voltage and generates a reference voltage, and an output of the time limit circuit section. A washer and wiper interlocking operating device comprising a comparison circuit section that compares the voltage with a reference voltage of the reference voltage generation circuit section and operates a wiper motor via an amplifier circuit section based on the comparison output.