JPS5881842A - Intermittent wiper driving controller - Google Patents

Abstract

PURPOSE:To correctly set a time interval of intermittent wiper driving, by changing a reference signal with the time from an oscillator, fetching and storing the reference signal at a desired point of time then setting the time interval of wiper intermittent driving on the basis of said stored reference signal. CONSTITUTION:Oscillating output from an oscillator 1 is converted into a reference signal, in which its signal level is gradually changed in accordance with the lapse of time, in a D-A converter 2. Simultaneously with generation of this reference signal, an initial working circuit 3 is operated. A sample hold circuit 4 operates by the action of this circuit 3, if a switch SW is controlled at a desired point of time, the reference signal at said point of time is stored in the circuit 4. Then if each level of output of the converter 2 and output of the circuit 4 is aligned, output of a comparator circuit 5 is inverted, and an intermittent relay operating circut 7 is operated. While simultaneously a reset circuit 6 is operated to reset the converter 2. The converter 2 again generates a reference signal, if said signal is aligned to the signal, stored in the circui 4, an output of the circuit 5 is inverted to operate the operating circuit 7.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wiper intermittent drive control device for controlling intermittent drive of a vehicle wiper.

Conventionally, this type of device is a timer circuit formed by a resistor and a continuum tc, which is installed in a wiper drive device, and is configured to control the time interval of intermittent driving of the rewiper by changing the time constant of the timer circuit. It has been known.

In other words, in such conventional devices, the time constant of the timer circuit is made variable by, for example, the resistance of the circuit, and the time interval of intermittent driving of the wiper is adjusted using the rotation angle of a knob connected to the resistance as a guide.

However, since the intermittent drive interval of the wiper is set in advance based on the rotation angle of the knob (42) in this conventional device, such setting is inevitably a process of trial and error. In other words, there is a problem in that it is necessary to modify the set amount many times depending on the weather conditions or the driving speed 6 during driving, which is extremely troublesome.

The present invention has been made in view of the above-mentioned problems of the prior art, and it is an object of the present invention to provide a wiper intermittent drive control device that can immediately set the time interval in the wiper intermittent drive as desired. With the goal.

The present invention will be described below with reference to the drawings.

First, the configuration will be explained. FIG. 1 is a block diagram showing one embodiment of the present invention. According to C2, reference numeral 1 is an oscillator, and this oscillator 1 is connected to a digital-to-analog (DA) converter 2 as a conversion circuit. On the other hand, code 3
is an initial activation circuit, and this initial activation circuit is connected to the sample and hold circuit 4. The output terminals of the DA converter 2 and the sample and hold circuit 4 are respectively connected to the input terminal of the comparator circuit 5. This comparison circuit 5
The output terminal of is connected to a wiper (not shown) and to an intermittent relay operating circuit 7 constituting the wiper drive circuit i, and the above-mentioned initial operating circuit 3 is connected to this intermittent relay operating circuit 7. Further, the intermittent relay operating circuit is connected to the DA converter 2 via the reset circuit 6. Further, a switch history is provided between the DA converter 2 and the sample and hold circuit 4.

With this configuration, the oscillation output obtained by the oscillator 1 is converted by the DA converter 2 into a reference signal whose signal level gradually changes with the passage of time. This reference signal is generated during intermittent driving of the wiper, and the initial activation circuit 3 is activated at the same time as this signal is generated. The sample and hold circuit 4 operates from the operation C2 of the initial operation circuit 3, and when the switch history is operated at a desired time, the reference signal at that time can be taken out, and the reference signal is stored in the sample and hold circuit 4. . On the other hand, the comparison circuit 5 has D-A
Since the outputs of the converter 2 and the sample hold circuit 4 are supplied, the reference signal obtained from the DA converter 2 and the sample hold circuit 4C; when the signal levels of the stored reference signals match, the comparison circuit 5 The output of is inverted.

This inverted output activates the intermittent relay activation circuit 7, so that the wiper sweep is performed once. When the output of the comparator circuit 5 is inverted, the reset circuit 6 operates, so the D-A conversion ls2
is reset, and the DA converter 2 again monitors the passage of time (=
A reference signal that varies accordingly is generated, and wiper sweeps are performed intermittently at intervals from the time of its initial level to the time of operating the switch history. Note that the DA converter 2 can be an integrator having similar characteristics.

Next, a more detailed embodiment constructed based on the block diagram C shown in FIG. 1 will be described with reference to FIG. 2.

In FIG. 2, the symbol VO is a power supply, and the station is a wiper drive motor constituting a wiper drive circuit, and the power supply V
o is connected to one end of the motor MO.

The two other ends of this motor drive are connected respectively to terminals H and L of a wiper switch that changes the drive mode of the wiper. By the way, is this Waiba Sui? WS has the connection relationship shown in Table G in the figure, and when the off mode is OFF, the terminal M
and terminal RI are connected, and when in intermittent mode INT, terminal ! The terminals E1, M, and RI are connected to each other by □. LO is connected to terminal E and terminal RI when in low speed mode, and H is connected to terminal E and terminal H when in high speed mode. Here, the terminal E is grounded. Further, one end of the motor M is connected to a terminal M via an auto-stop switch A8 and a relay contact R8.

The emitter of the transistor T4 is connected to the voltage IVol2, and its collector is connected to the controller power supply Vcc. And the base of transistor T4 is resistor R
6 to terminal I. The controller power source is connected to one end of the resistor R1 of the initial operation circuit 3 and to one side of the resistor R1, respectively. The resistor B1 is connected in series with the resistor R2, one end of the resistor R2 is grounded, and its voltage dividing point is connected to the drain of the field effect transistor FET. Further, the resistor R3 is connected in series with the capacitor C16, and the connection point thereof is connected to the resistor Rn1 through a NOT element NOT. One end of the resistor R4 is connected to the gate of the field effect transistor FET, and this gate is connected to the base of the transistor T1 via the resistor R5, whose terminal is grounded.

The source of the field effect transistor FBT of the initial operation circuit 3 is connected to the non-inverting input terminal of the operational amplifier A2 of the sample-and-hold circuit 4, and this non-inverting input terminal is grounded via the capacitor C2. Further, the output terminal of the operational amplifier A2 is connected to the inverting input terminal.

On the other hand, oscillator 1 consists of two NOR elements N connected in series 1
It is formed by OR, a resistor R7 connected to its connection point, a resistor R8 connected to the output terminal of one NOR element NOH, and a capacitor Ci, and is a type of oscillator. The resistor R8 of the oscillator I is connected to the input terminal C of the two-way counter of the DA converter 2. This binary counter is, for example, a 4-bit counter, and the output terminal of this counter center (: is connected to a ladder resistor consisting of resistors r, . . . r8, The output terminal is connected to the non-inverting input terminal of operational amplifier A1.The inverting input terminal of operational amplifier A1 is connected to its output terminal 4.
:It is connected. The output of the operational amplifier A1 is connected to the non-inverting input C2 of the operational amplifier 2 via a self-resetting switch with normally open contacts.

In this way, the output of the DA converter 2 is connected to the inverting input terminal of the operational amplifier S of the comparator circuit 5, and the output terminal of the operational amplifier A2 of the sample and hold circuit 4 is connected to its non-inverting input terminal via the resistor R1o. has been done.

The output terminal of the operational amplifier A5 is connected via a resistor Rn to its non-inverting input terminal (both connected C; resistor R1
! It is connected to the base of the transistor T2 in the intermittent relay operation circuit 7 via the intermittently relay operating circuit 7.

The terminal of the transistor T2 of the intermittent relay operating circuit 7 is grounded, and its collector is connected to the controller power supply (== connected) via the resistor R+i.
The base of 2 is connected to the collector of the transistor T1 of the initial activation circuit 3. Further, the collector of the transistor T2 is connected to the base of the transistor Tl via a resistor R14, and this base is grounded via a resistor &@. Furthermore, the emitter to the transistor is grounded, and its collector is connected to the power supply vO via the intermittent relay energization signal YC. Further, the collector of the transistor T2 is connected to one end of the resistor R1 of the reset circuit 6. This resistor R9 constitutes the reset circuit 6 together with the capacitor C4, and the connection point of the resistor R9 and the capacitor C4 is connected to the reset terminal C of the binary counter.

Next, the operation of the embodiment constructed based on FIG. 2C will be explained with reference to the time chart of FIG. 3.

First, set the wiper switch (2) to intermittent mode (INT) and turn on the controller power source (see FIG. 3 (a)). As a result, the initial operation circuit 3 operates and starts charging the capacitor C1. During charging of capacitor C1, knot element NO
Since T is outputting a high level, the field effect transistor FET and transistor T1 are on (
(See Figure 3). Therefore, the comparator C2 of the comparison circuit 4 is charged and the output level of the operational amplifier A2 is held (see FIG. 3(G)). When the transistor T1 is turned on, the transistor T2 is turned off, turning on the transistor T5, and the excitation coil π of the intermittent relay is energized to turn on the relay contact R8. Transistor T2 off 1: Reset circuit 6 is activated (see Figure 3)
2-way counter reset. In addition, when the relay contact section is turned on, the motor power is swept once by the wiper;
It rotates as much as you can. When the capacitor C1 is fully charged, the potential at the check point a becomes constant, and this potential inverts the output of the NOT element so that the check point a becomes low level (see FIG. 3), and the transistor T1 is turned off. Since the transistor T1 is turned off (second check point C becomes high level (see FIG. 3)), the transistor T2 is turned on and the reset of the binary counter is released.

On the other hand, when the wiper switch is turned on, the oscillator 1 starts to oscillate a rectangular wave pulse of a predetermined frequency (see Figure 3).
. Upon receiving this pulse, the binary counter heart whose reset is released starts counting (see FIG. 3). This counter core is synchronized with the output pulse of the oscillator 1 and performs 16 counts from 0000 to 1111 in binary code.

From this count output C2, the ladder resistance r,...
・・・R8 increases the potential at check point d stepwise by 1/16 of the power supply voltage every 1 count. The connected operational amplifier A1 functions to prevent voltage fluctuations on its output side when the switch is turned on and the capacitor C2 is charged.

In this way, when the potential at check point d becomes greater than that at check point , the output of the operational amplifier is inverted, and check Ac becomes low level. That is, transistor T2
is turned off, transistor T5 is turned on, and intermittent relay contact R8 is operated, and the counter value C is reset. Thereafter, this operation is repeated until the wiper is driven intermittently at the maximum period Ta as shown in FIG.

Next, there is a desired point in time, for example, a point in time t when it is determined that the period of intermittent drive of the wiper should be changed depending on weather conditions.

When the switch is turned on at this point, the potential at the check point d at this time point to becomes the same as the level at the non-inverting input terminal of the operational amplifier A2 (see FIGS. 3(f) and (g)).

Next, when the switch history is turned off at time t1, the check point
The potential -2 of is held at the same level as the potential of check point d at that time. This held potential is determined by the time interval C from the initial level of the check point d, that is, the minimum level gIo of the reference signal, from - to the time t2.
Two proportionate. In other words, when the check point - is held at the potential level, the output of the operational amplifier 5 becomes inverted so that it is inverted at the time t2 when the level of the check point d exceeds the potential g2. As described above, the output inversion of the operational amplifier A5 turns off the transistor T2, thereby resetting the counter and energizing the excitation coil YC of the intermittent relay. Thereafter, this operation is repeated, and the wiper is driven intermittently at a period T. Note that the reset circuit 6 has a time constant determined by the resistor C4 and the capacitor C4, and this time constant determines the time 1. This is to determine (=).

Moreover, the period of intermittent driving of the wiper is set arbitrarily C2 within the range of the maximum period Ta after the wiper is swept once by turning the switch on and off.

As explained above, the present invention includes a conversion circuit that generates a reference signal whose initial signal level changes gradually over time during wiper drive, and a conversion circuit that extracts and stores the reference signal at a desired point in time. a sample-and-hold circuit that compares the outputs of the conversion circuit and sample-and-hold circuit; and a comparison circuit that compares each output of the conversion circuit and sample-and-hold circuit; Since the wiper drive circuit is equipped with a wiper drive circuit that drives the wiper at intervals of Interval I: Can be set accurately. Also, as a means of extracting the reference signal at a desired point in time, it is possible to
Since an off operation can be used, the operation is extremely simple.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing one embodiment of the present invention, FIG. 2 is an electric circuit diagram showing a more detailed embodiment constructed based on the block diagram of FIG. 1, and FIG. 3 is a time chart illustrating the operation of FIG. 2... D-me converter (conversion circuit), 4... Sample hold circuit, 5... Comparison circuit, 7... Intermittent relay operating circuit (wiper drive circuit). 'rog11 pregnancy (il,,) -195-

Claims (1)

[Claims] A conversion circuit that generates a reference signal whose initial signal level changes gradually over time during wiper drive, and a sample hold that extracts and stores the reference signal at a desired time point C: a comparator circuit that compares each output of the converter circuit and the sample-and-hold circuit; and when the comparator circuit is activated, resets the converter circuit to change the reference signal from the initial level to the desired time point. 1. A wiper intermittent drive control device comprising: a wiper drive circuit that drives the wiper at intervals of .