JPH0524512A - Simple type car speed sensitive wiper device for automobile - Google Patents

Abstract

PURPOSE:To provide an automatic switching device which can be easily built in an existing wiper system to realize a car speed sensitive wiper system. CONSTITUTION:Frequency of pulse-formed car speed signals is converted into the voltage level by using an interface circuit 7b, a differential circuit 7c, the first diode 7d and a smoothing capacitor 7e, and the frequency is received by the first transistor 7f. An electromagnetic relay 7j does not work since a counter 7h is reset due to the OFF activation in the low speed travelling condition where the first transistor 7f repeats ON/OFF activation due to the pulse components included in the terminal voltage of the smoothing capacitor 7e. The output terminal Q2 becomes HIGH when the count number of the counter 7h exceeds 2 in the high speed travelling condition where the terminal voltage of the smoothing capacitor 7e exceeds the ON-voltage of the first transistor 7f, and an electromagnetic relay 7j is turned ON. The HIGH signal is supplied to a clock terminal CLK through the third diode 7k, the counter 7h stops counting, and the electromagnetic relay 7j maintains the ON condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simplified vehicle speed sensitive wiper device for automobiles.

[0002]

2. Description of the Related Art A wiper switch, a running detector for detecting a running state of a vehicle and issuing a running signal, and a control for executing an operation mode selected by the wiper switch among a plurality of operation modes. And a circuit,
When the wiper switch is selected in an operation mode other than the intermittent operation mode, the control circuit lowers the operation mode by one step when the running signal changes from the presence state to the absence state, and the wiper switch operates intermittently. A wiper control device for a vehicle has already been developed, which is adapted to change and execute an intermittent time by a preset calculation method when the running signal changes from the presence to the absence in the operation mode. 62-21
Published in Japanese Patent No. 0155.

[0003]

The vehicle speed sensitive wiper device as described above generally calculates a vehicle speed from a vehicle speed pulse by a complicated electronic circuit using a microcomputer or the like, and sets the wiper speed to a wiper speed corresponding to the vehicle speed. Although it is controlled, such a method has a problem that a large number of expensive parts such as a microcomputer must be used and a large increase in cost cannot be avoided.

The present invention has a configuration that can be easily incorporated into an existing wiper system, but the number of the wiper system can be regarded as almost stopped.
Distinguishing extremely low speed running state of about km / h from high speed running state, and maintaining the wiper stopped state or intermittent operation state at the time of the extremely low speed running as well as the stopped state, to ensure quietness and consume the wiper. It is an object of the present invention to provide a simplified vehicle speed sensitive wiper device capable of reducing electric power.

[0005]

SUMMARY OF THE INVENTION According to the present invention, a wiper which is in an intermittent or stopped state when a vehicle is stopped or traveling at a speed lower than a set vehicle speed is automatically switched to a low speed operation state when the vehicle runs at a speed higher than the set vehicle speed. An operation switch for supplying power to the automatic switching device from a vehicle-mounted power supply, an interface circuit for interfacing a vehicle speed signal from a vehicle speed sensor, and a differentiating circuit for differentiating the vehicle speed signal to generate a pulse signal. A first diode that cuts the negative side of the pulse signal, a smoothing capacitor that smoothes the pulse signal that has been cut on the negative side, and an ON operation when the terminal voltage of the smoothing capacitor exceeds a predetermined voltage. The first transistor, a reset terminal connected to the output terminal of the first transistor, and a second backflow prevention second terminal for the output terminal of the interface circuit. A counter provided with a clock terminal connected via an ion and an output terminal for outputting an output signal when the count value of a square wave vehicle speed signal input to the clock terminal reaches a predetermined value, and the input terminal is the above counter A second transistor connected to the output terminal of the
The electromagnetic relay that is turned on when the transistor is turned on and connects the low-speed operation terminal of the wiper motor directly to the power supply, and is interposed between the output terminal and the clock terminal of the counter, and is directed from the output terminal side to the clock terminal side. Is composed of a third diode in the forward direction.

[0006]

As described above, when the vehicle travels at a low speed less than the set vehicle speed, the voltage waveform pulse accompanied by the pulse input to the input terminal of the first transistor as a vehicle speed signal is generated when the voltage is near the ON voltage of the first transistor. The first transistor is completely prevented from turning on and off, and the wiper is stopped or the operation is switched from the intermittent operation to the low speed operation smoothly when the low speed running below the set vehicle speed is switched to the high speed running above the set vehicle speed. Can be done.

[0007]

1 is a circuit diagram showing an embodiment of the present invention.
In (A), the one in which the B terminal and the C terminal are directly connected is a circuit diagram of a conventional wiper device.

FIG. 1 in which the B terminal and the C terminal are directly connected.
In (A), 1 is a wiper switch, and when the wiper switch 1 is operated from OFF to the interval position INT, a signal from the power source 2 is applied to the intermittent operation unit 4 via the ignition switch 3, and the intermittent operation unit 4 is operated. 4 operates intermittently to operate the wiper motor 5, and when the wiper switch 1 is set to the low position LO, the power supply 2 and the low speed operation terminal L of the wiper motor 5 are connected, the wiper motor 5 operates at low speed, and the wiper switch 1 is set to high. When the position HI is set, the power source 2 and the high speed operation terminal H of the wiper motor 5 are connected to operate the wiper motor 5 at high speed,
By operating these wiper motors 5, a wiper plate (not shown) wipes the window glass. Reference numeral 6 denotes an auto stop switch. The auto stop switch 6 is switched to the side indicated by the dotted line in FIG. 1 (A) during the wiper wiping operation in tandem with the wiper wiping operation by a cam mechanism (not shown). When the wiper switch 1 is off, the auto stop circuit from the power supply 2 to the low speed operation terminal L of the wiper motor 5 via the auto stop switch 6 and the off contact of the wiper switch 1 is closed to operate the wiper to the rest position and reach the rest position. Then, since the auto stop switch 6 is switched to the side indicated by the solid line in FIG. 1A, the auto stop circuit from the power source 2 to the wiper motor 5 is closed and the wiper is configured to stop at the rest position.

As described above, the present invention relates to an automobile wiper device in which each mode of the wiper motor 5 can be selected from low speed operation, high speed operation and intermittent operation by operating the wiper switch 1 according to the present invention. Off or intermittent operation state when a running state above a set vehicle speed (for example, a set vehicle speed set within a range of 5 km / h to 10 km / h) is detected when the vehicle that is performing 5 off operation or intermittent operation is stopped. The automatic switching device 7 for switching the wiper motor 5 in FIG.

The automatic switching device 7 is shown in FIGS. 1 (A) and 1 (B).
As shown in FIG. 3, the A terminal connected to the power source 2 and the relay unit 4a of the intermittent operation unit 4 from the auto stop switch 6 are connected.
The automatic stop switch 6 of the wiring extending to the S1 contact of the wiper switch 1 through the relay section 4a of the intermittent operation unit 4 is disconnected, and the B and C terminals provided at both ends thereof, and the OFF operation of the wiper switch 1 and Wiper motor 5 and S2 terminal that communicates with S1 terminal during intermittent operation
The terminal of the same name is connected to the D terminal provided on the way to the low speed operation terminal L of the vehicle, and the E terminal is connected to the vehicle speed sensor (not shown) and the vehicle speed signal is supplied from the vehicle speed sensor. ..

FIG. 1 showing an embodiment of the automatic switching device 7
In (B), the automatic switching device 7 includes an operation switch 7a provided between the power source 2 and the automatic switching device 7 for supplying electric power to the automatic switching device 7, a diode and a pull-up resistor, and a vehicle speed not shown. An interface circuit 7b for interfacing the vehicle speed signal supplied from the sensor through the E terminal, a differentiating circuit 7c for differentiating the interfaced vehicle speed signal to generate positive and negative pulse signals, and the positive and negative pulse signals First diode 7d for cutting the negative side
A smoothing capacitor 7e for smoothing the pulse signal with the negative side cut off, a first transistor 7f that is turned on when the terminal voltage of the smoothing capacitor 7e becomes equal to or higher than a predetermined voltage, and the first transistor 7f. The reset terminal RST connected to the output terminal of the transistor 7f, the clock terminal CLK connected to the output terminal of the interface circuit 7b through the second diode 7g for backflow prevention, and the clock terminal CLK are input to the clock terminal CLK. CMOS 14040 provided with an output terminal Q2 that outputs an output signal when the count value of a square wave vehicle speed signal reaches a predetermined value (for example, 2).
A counter 7h such as B and the input terminal is the counter 7
second transistor 7i connected to output terminal Q2 of h
When the second transistor 7i is turned on, the second transistor 7i is turned on to switch between the contacts (B) and (C) from closed to open, and also between the contacts (A) and (D) from open to closed. Electromagnetic relay 7j and output terminal Q of the counter 7h
2 and the clock terminal CLK, which is interposed between the output terminal Q2
The third diode 7k has a forward direction from the side toward the clock terminal CLK.

In the above, when the vehicle is in the stopped state and the running state is equal to or higher than the set vehicle speed, the output of the interface circuit 7b has the same phase as the vehicle speed signal supplied from the vehicle speed sensor (not shown) through the E terminal. A square wave output voltage as shown in FIG. The output voltage of the square wave generated at the output side of the interface circuit 7b is differentiated by the differentiating circuit 7c composed of a capacitor and a resistor.
The waveform is as shown in (B). From this waveform, the negative side is cut by the first diode 7d to form a pulsed output voltage which is smoothed by the smoothing capacitor 7e and applied to the base terminal of the first transistor 7f.

As the vehicle speed increases, the cycle of the pulsed output voltage generated at the output side of the differentiating circuit 7c becomes shorter, and as a result, the terminal voltage generated at the terminal of the smoothing capacitor 7e is as shown in FIG.
As shown in (C), it increases according to the vehicle speed. That is, the frequency of the pulse-shaped vehicle speed signal is converted into the voltage level. When the vehicle speed increases and the terminal voltage of the smoothing capacitor 7e rises and exceeds the on-voltage of the first transistor 7f, the first transistor 7f is turned on. The terminal voltage of the smoothing capacitor 7e becomes high until it exceeds the on-voltage of the first transistor 7f during running,
When the vehicle is stopped, the electric charge charged in the smoothing capacitor 7e is discharged by the resistor R1 and the first transistor 7f, so that the terminal voltage of the smoothing capacitor 7e is the first transistor 7e.
It falls below the on-voltage of f, and as a result, the first transistor 7f is turned off.

Therefore, if the electromagnetic relay 7j is connected to the output terminal of the first transistor 7f, the wiper can be controlled by the vehicle speed, but this has a problem.

FIG. 2C shows the terminal voltage of the smoothing capacitor 7e when the vehicle is running at a high speed above the set vehicle speed, and FIG. 2D shows the terminal voltage of the smoothing capacitor 7e when the vehicle is running at a low speed below the set vehicle speed. It is a thing.

When the vehicle is traveling at a high speed above the set vehicle speed, FIG.
As shown in FIG. 2, the terminal voltage with a small voltage change is shown, but when the vehicle is traveling at a low speed less than the set vehicle speed, the period of the pulsed output voltage generated from the differentiating circuit 7c is slow as shown in FIG. 2B. Therefore, as shown in FIG. 2D, the smoothing function of the smoothing capacitor 7e is insufficient and the smoothing capacitor 7e is
It has a voltage waveform with a pulse due to the charging and discharging of e. When the electromagnetic relay 7j is driven by the terminal voltage of the smoothing capacitor 7e carrying such a pulse, when there is a pulse just near the ON voltage of the first transistor 7f, the first transistor 7f is turned on / off by the pulse. As a result, the electromagnetic relay 7j is activated. Therefore, when the terminal voltage of the smoothing capacitor 7e is pulsed during low speed traveling below the set vehicle speed, it is necessary to control so that the electromagnetic relay 7j is not activated, and the counter 7h does this.

The counter 7h is a binary counter IC which counts the number of pulses applied to the clock terminal CLK when the reset terminal RST is low. When a square wave output voltage generated at the output side of the interface circuit 7b during high speed traveling above the set vehicle speed is applied to the clock terminal CLK through the second diode 7g for backflow prevention, the counter 7h outputs a square wave. The number of voltage repetitions is counted, and when the number of counts exceeds 2, the output terminal Q2 of the counter 7h becomes high and the second transistor 7i is turned on, whereby the electromagnetic relay 7j is activated and the A terminal and the D terminal are connected. During this period, the open circuit is switched to the closed state, so that the energizing circuit from the power supply 2 to the low speed operation terminal L of the wiper motor 5 via the A terminal and the D terminal is closed, and the wiper motor 5 operates at low speed.

However, when the vehicle is traveling at a low speed less than the set vehicle speed (for example, several km / h), the first transistor 7f is turned on as shown in FIG.
When the voltage applied to the reset terminal RST of the counter 7h is in a pulse state by being driven by a voltage waveform with a pulse as shown in FIG. The square wave output voltage of the interface circuit 7b applied via the second diode 7g for use is counted, but the count value is reset immediately before the count at which the output terminal Q2 becomes high, and the electromagnetic relay 7j Does not work,
Since the closed state is maintained between the B terminal and the C terminal, the power source 2
Since the energizing circuit from the automatic stop relay 6, the B terminal, the C terminal, and the OFF contact of the wiper switch 1 to the low speed operation terminal L of the wiper motor 5 remains closed, the wiper motor 5 selected by the wiper switch 1 when the vehicle is stopped. OFF operation or intermittent operation is continuously performed.

When the vehicle travels at a high speed above the set vehicle speed, the first
Transistor 7f remains on and counter 7h
Since the voltage applied to the reset terminal RST of the counter 7h is kept low, the counter 7h is not reset and the second diode 7g for preventing backflow from the interface circuit 7b.
Count the square wave output voltage given through
When the count value exceeds 2, the output terminal Q2 becomes high, the electromagnetic relay 7j operates, and the connection between the A terminal and the D terminal is closed, whereby the wiper motor 5 operates at a low speed.

When the counter 7h continues counting as it is, the output terminal Q2 of the counter 7h is repeatedly turned on and off depending on the number of counts.
When 2 becomes high, it is necessary to stop the output voltage of the interface circuit 7b, which is given through the second diode 7g for shaping backflow prevention, from being input to the counter 7h. The third direction, which is interposed between the output terminal Q2 of the counter 7h and the clock terminal CLK, has a forward direction from the output terminal Q2 side toward the clock terminal CLK side.
It is the diode 7k.

That is, the output signal from the output terminal Q2 of the counter 7h activates the electromagnetic relay 7j via the second transistor 7i, and at the same time, the third diode 7k.
Is supplied to the clock terminal CLK via the clock terminal CLK, and the potential of the clock terminal CLK is kept high.
Even if a vehicle speed signal is input to LK, the vehicle speed signal is not counted, the count number of the counter 7h does not increase, and the potential of the output terminal Q2 remains high. Therefore, when the vehicle travels at a speed higher than the set vehicle speed, the electromagnetic relay 7j remains activated, the A terminal and the D terminal are closed, and the wiper motor 5 operates at a low speed. The output terminal Q2 of the counter 7h becomes low level because the low-speed running below the set vehicle speed shifts, the cycle of the pulsed output voltage generated from the differentiating circuit 7c is delayed, and the terminal voltage of the smoothing capacitor 7e is the first. The electric voltage stored in the smoothing capacitor 7e is equal to or lower than the on-voltage of the transistor 7f of FIG.
This is when the voltage is discharged through f and the terminal voltage of the smoothing capacitor 7e becomes equal to or lower than the ON voltage of the first transistor 7f. When the potential applied to the reset terminal RST of the counter 7h becomes high due to the off operation of the first transistor 7f, the counter 7h is reset and the electromagnetic relay 7j is turned off, so that the A terminal and the D terminal are open and the B terminal is opened. The terminals C and C are closed, and the wiper motor 5 can be selected from normal low speed operation, high speed operation and intermittent operation by operating the wiper switch 1.

When the vehicle is started while the operation switch 7a of the automatic switching device 7 is operated and the vehicle moves to a high speed running above the set vehicle speed, the wiper motor 5 stopped or intermittently operated by the operation of the automatic switching device 7 becomes low speed. It operates, but it goes without saying that when the rain pad becomes strong and the wiper switch 1 is operated at a high position, the operation of the wiper switch 1 has priority over the operation of the operation switch 7a of the automatic switching device 7 and the wiper motor 5 operates at high speed. ..

[0023]

As described above, according to the present invention, the wiper which is in the intermittent or stopped state when the vehicle is stopped or traveling at a speed lower than the set vehicle speed is automatically set to the low speed operating state when the wiper travels at the set vehicle speed or higher. The automatic switching device for switching, an operation switch for supplying electric power from the vehicle-mounted power source to the automatic switching device, an interface circuit for interfacing a vehicle speed signal from a vehicle speed sensor, and a differentiating circuit for differentiating the vehicle speed signal to generate a pulse signal. A first diode that cuts the negative side of the pulse signal, a smoothing capacitor that smoothes the pulse signal that has been cut on the negative side, and an ON state when the terminal voltage of the smoothing capacitor exceeds a predetermined voltage. The first transistor for operation, the reset terminal connected to the output terminal of the first transistor, and the backflow prevention first terminal for the output terminal of the interface circuit. A counter having a clock terminal connected via the diode and an output terminal that outputs an output signal when the count value of the vehicle speed signal input to the clock terminal reaches a predetermined value, and the input terminal outputs the counter. Between a second transistor connected to the terminal, an electromagnetic relay that is turned on when the second transistor is turned on and directly connects the low-speed operation terminal of the wiper motor to the power source, and between the output terminal of the counter and the clock terminal. Since the third diode is interposed and has a forward direction from the output terminal side toward the clock terminal side, it is input to the input terminal of the first transistor as a vehicle speed signal when traveling at a low speed less than the set vehicle speed. ON of the first transistor generated when the pulse of the voltage waveform carrying the pulse is near the ON voltage of the first transistor. It is possible to completely prevent the off operation, smoothly stop the wiper or switch from the intermittent operation to the low speed operation when shifting from the low speed traveling less than the set vehicle speed to the high speed traveling above the set vehicle speed, and the existing The vehicle speed sensitive wiper can be easily incorporated into the wiper system described above to provide a great practical effect in combination with the simple structure.

[Brief description of drawings]

FIG. 1 shows an embodiment of the present invention, in which (A) is an overall circuit diagram of a vehicle-type simplified vehicle speed-sensitive wiper device, and (B) is a detailed circuit diagram of the automatic switching device shown in (A).

2A and 2B are time charts showing voltage waveforms at various points of the automatic switching device shown in FIG. 1B, in which FIG. 2A shows the output voltage of the interface circuit, and FIG. 2B shows the output voltage of the differentiating circuit. , (C) show the terminal voltage of the smoothing capacitor during high speed running, and (D) show the terminal voltage of the smoothing capacitor during low speed running.

[Explanation of symbols]

 1 Wiper Switch 2 Power Supply 3 Ignition Switch 4 Intermittent Operation Unit 5 Wiper Motor 6 Auto Stop Switch 7 Automatic Switching Device 7a Operation Switch 7b Interface Circuit 7c Differentiation Circuit 7d First Diode 7e Smoothing Capacitor 7f First Transistor 7g Second Diode 7h Counter 7i Second transistor 7j Electromagnetic relay 7k Third diode

Claims (1)

Claims: 1. An automatic switching device for automatically switching a wiper, which is in an intermittent or stopped state when the vehicle is stopped or traveling at a speed lower than a preset vehicle speed, to a low speed operation state when traveling at a speed equal to or higher than the preset vehicle speed. An operation switch for supplying electric power from the vehicle-mounted power source to the automatic switching device, an interface circuit for interfacing a vehicle speed signal from a vehicle speed sensor, a differentiating circuit for differentiating the vehicle speed signal to generate a pulse signal, and the pulse A first diode that cuts the negative side of the signal, a smoothing capacitor that smoothes the pulse signal that has been cut on the negative side, and a first diode that is turned on when the terminal voltage of the smoothing capacitor exceeds a predetermined voltage. Transistor, a reset terminal connected to the output terminal of the first transistor, and a second diode for preventing backflow at the output terminal of the interface circuit. A counter having a clock terminal connected via a clock terminal and an output terminal that outputs an output signal when the count value of the square wave vehicle speed signal input to the clock terminal reaches a predetermined value, and the input terminal is the counter described above. A second transistor connected to the output terminal of the counter, an electromagnetic relay that is turned on when the second transistor is turned on, and directly connects the low-speed operation terminal of the wiper motor to the power source, the output terminal of the counter, and the clock terminal. A simplified vehicle speed-sensitive wiper device for an automobile, comprising a third diode which is interposed between the output terminal side and the clock terminal side and which has a forward direction.