JPS6311003Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit device capable of driving wipers for windshields and rear windows of automobiles, etc.

In general, wiper drive circuit devices allow the wiper drive motor to be selected between low-speed operation, high-speed operation, and intermittent operation by operating a wiper speed selection switch. Since the main current flowing through the motor also flows through the wiper speed selection switch, the contact capacity of the wiper speed selection switch must be increased, which poses the problem of increasing the size of the wiper speed selection switch.

The present invention attempts to solve such problems by passing a weak control current that controls the opening and closing of the main current to the wiper speed selection switch instead of the above-mentioned main current. It is an object of the present invention to provide a main current indirect control type wiper drive circuit device in which the size of a wiper speed selection switch is reduced by reducing the contact capacity of the switch.

Therefore, the main current indirect control type wiper drive circuit device of the present invention has a wiper drive circuit that can selectively control the wiper drive motor among low speed operation, high speed operation, and intermittent operation using a wiper speed selection switch. Between,
A first power relay switch for high-speed operation is provided, and a second power relay switch is provided for both low-speed operation and intermittent operation, and the main current flows to the wiper drive motor through each of the power relay switches. The wiper speed selection switch is interposed in a circuit for turning on and off the excitation coils of the first and second power relay switches in order to indirectly control opening and closing of the power relay switch.

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is an electric circuit diagram showing a main current indirect control type wiper drive circuit device as the first embodiment. hand,
A first power relay switch 3 and a second power relay switch 4 connected in parallel are connected.

The first power relay switch 3 is composed of an excitation coil 3a and a switch section 3b that closes when the excitation coil 3a is excited and opens when it is demagnetized. It is connected to the terminal Hi of the selection switch 5, and the other end is grounded.

The switch portion 3b has one end connected to the battery 1 via the fuse 2, and
The other end is connected to the H terminal of the wiper drive motor 6.

Further, the second power relay switch 4 is connected to the first power relay switch 4.
excitation coil 4a, and this first excitation coil 4a.
When the first excitation coil 4a is demagnetized, the first switch section 4b is tilted toward the B terminal side, and when the first excitation coil 4a is demagnetized, the switch section 4b is tilted toward the S terminal side, and a second excitation coil 4c; A second switch section 4d with a return spring that opens when the second excitation coil 4c is excited and closes when it is demagnetized.
It is composed of the following.

The first excitation coil 4a has one end connected to the battery 1 via the fuse 2, and the other end connected to the terminal 7a of the interval wiper relay circuit 7. , its B terminal is connected to the battery 1 via the fuse 2, its S terminal is connected to the S terminal of the wiper drive motor 6, and its L terminal is connected to the L terminal of the wiper drive motor 6 via the second switch section 4d. connected to the terminal.

The second excitation coil 4c is connected in parallel with the excitation coil 3a of the first power relay switch 3, one end of which is connected to the battery 1 via the fuse 2, and the other end is grounded. There is.

The wiper drive motor 6 is a motor that operates at low speed when current is supplied to its L terminal, and operates at high speed when current is supplied to its H terminal.
It is equipped with

This auto-stop mechanism 8 includes a cam 8a that is linked to a motor section, and a cam 8a that operates according to the movement of the cam 8a.
It includes a switch piece 8b that can come into contact with the + terminal and the E terminal.

The + terminal is connected to the battery 1 via the fuse 2, and the E terminal is grounded.

By the way, the wiper speed selection switch 5 is
When this is set to the high-speed operation position HIGH, terminal B and
The switch is configured so that when the switch is set to the low speed operating position LOW, terminal B and Lo are electrically conductive, and when the intermittent operating position is set to INT, the terminal E and INT are electrically conductive, and the terminal B is connected to the fuse. 2 to battery 1, its terminal E to ground, its terminal
INT is connected to the terminal 7b of the interval wiper relay circuit 7, its terminal Lo is connected to the base of the transistor Tr1 via the terminal 7c of the same circuit 7 and the resistor R1, and its terminal Hi is connected to the excitation of each power relay switch 3, 4 as described above. They are connected to ground via coils 3a and 4c, respectively.

Note that when the wiper speed selection switch 5 is set to the OFF position, all terminals are opened.

Therefore, for example, when the wiper speed selection switch 5 is set to the high-speed operation position HIGH, the excitation coils 3a and 4c are excited, the switch section 3b is closed, and the switch section 4d is opened, and the battery 1
The main current then flows through the first power relay switch 3 to the wiper drive motor 6, thereby causing the wiper drive motor 6 to operate at high speed. That is, the first power relay switch 3 is constructed as a relay switch for high-speed operation, and the wiper speed selection switch 5 is interposed in a circuit for turning on and off the excitation coil 3a of the first power relay switch 3. Therefore, only a weak current flows through this switch 5.

By the way, interval wiper relay circuit 7
operates in cooperation with the wiper speed selection switch 5 and the auto-stop mechanism 8, and controls the switching of the first switch portion 4b of the second power relay switch 4 to operate the wiper drive motor at low speed or intermittently. This is an electronic circuit for this purpose, and its functions are briefly described below.

Now, when the wiper speed selection switch 5 is set to, for example, the low speed operating position LOW, terminals B and Lo are electrically connected, so that the battery 1 is energized.
A bias voltage is applied by the resistor R1, and the transistor Tr1 is turned on. As a result, current flows from the battery 1 to the fuse 2, the first excitation coil 4a of the second power relay switch 4, the diode D1, and the transistor Tr1, the first excitation coil 4a is excited, and the first switch section 4b is is B
Since it falls to the terminal side, electricity is passed through the L terminal of the wiper drive motor 6, and the wiper drive motor 6
performs low speed operation.

Note that at this time, since the second exciting coil 4c is not excited, the second switch portion 4d is closed.

Next, when the wiper speed selection switch 5 is set to the intermittent operation position INT, the terminals E and INT are electrically connected, so that the terminal 7b of the interval wiper relay circuit 7 is grounded. This allows the transistor
Tr2 turns on, and the battery 1, the fuse 2, the first excitation coil 4a of the second power relay switch 4, and the terminal 7 of the interval wiper relay circuit 7
a, a current flows to the ground via the diode D2, the transistor Tr2, the terminal 7b of the electronic circuit 7, and the wiper speed selection switch 5, and the first excitation coil 4a of the second power relay switch 4 is excited. , the first switch portion 4b falls toward the B terminal side, and the wiper drive motor 6 operates at a low speed.

By operating the wiper drive motor 6 in this manner, when the switch piece 8b of the auto-stop mechanism 8 falls to the + terminal side, electricity is supplied from the terminal 7d of the interval wiper relay circuit 7, so that the transistor Tr3 is turned on. This turns off the transistor Tr2, and the switch piece 4b of the second power relay switch 4 falls toward the S terminal.

When the switch piece 4b falls to the S terminal side in this way, electricity is supplied only through the auto-stop mechanism 8, and the wiper drive motor 6 continues to rotate, but when the switch piece 8b falls to the E terminal side, electricity is supplied only through the auto-stop mechanism 8. The supply is cut off and the wiper drive motor 6 is stopped at this time.

As mentioned above, when the transistor Tr2 is turned off, the capacitor C1 is charged from the battery 1 through the terminal 7a of the electronic circuit 7, but this charging is carried out for a predetermined time until the capacitor C1 becomes fully charged. , this charging time becomes the time when the electronic circuit 7 is turned off.

Then, when the capacitor C1 becomes fully charged, the base current of the transistor Tr3 disappears, so the transistor Tr2 is turned on again, and the first excitation coil 4a of the second power relay switch 4 is turned on.
is excited, and the wiper drive motor 6 starts operating at low speed again.

In this way, the wiper drive motor 6 rotates, and the switch piece 8b of the auto-stop mechanism 8 is activated again.
When the voltage falls to the + terminal side, the transistor Tr2 is on, so the capacitor C1 is discharged. This discharge time becomes the time during which the electronic circuit 7 is turned on.

Thereafter, the wiper drive motor 6 is repeatedly turned on and off while repeating the above-described actions, thereby performing intermittent operation.

As a result, the second power relay switch 4 is configured as a relay switch for both low-speed operation and intermittent operation, and the wiper speed selection switch 5 is configured as a relay switch for both low-speed operation and intermittent operation. This switch 5 is interposed in a circuit for turning on and off the excitation coil 4a (a circuit including the transistor Tr1), so that only a weak current flows through the switch 5.

Note that if the resistor R2 is made a variable resistor, the intermittent time can also be adjusted.

Further, when the transistor Tr3 is turned on, a current flows through the terminal 7e of the electronic circuit 7 and the resistor R3.

Furthermore, in the electronic circuit 7, symbols R4 to R6
indicates a resistor, D4 a diode, and C2 a capacitor.

Further, in FIG. 1, reference numeral 9 denotes a washer switch for supplying washer fluid to the wiper sweeping surface;
Reference numeral 10 indicates a washer motor that is activated when the washer switch 9 is turned on.

FIG. 2 is an electrical circuit diagram showing a main current indirect control type wiper drive circuit device as a second embodiment of the present invention. In FIG. 2, the same reference numerals as in FIG. 1 indicate almost the same parts. There is.

This second embodiment is a device using a wiper speed selection switch grounding method, in contrast to the power relay grounding method of the first embodiment, and the effect when the wiper speed selection switch 5 is operated to each selected position. is almost the same as in the first embodiment described above.

For example, when the wiper speed selection switch 5 is set to the low speed operating position LOW, the transistors Tr1',
Since Tr1 is turned on, the excitation coil 4'a of the second power relay switch 4', which serves both for low-speed operation and intermittent operation, is excited.

As a result, the switch portion 4'b is attracted against the return spring 4'e, and the terminals 4'f, 4'
g, the main current flows from the battery 1 to the fuse 2, to the terminal 4'f of the second power relay switch 4', to the switch section 4'b, to the terminal 4'g, to the first
The power flows to the L terminal of the wiper drive motor 6 through the terminal 3'c, the switch section 3'b, and the terminal 3'd of the power relay switch 3', and as a result, the wiper drive motor 6 operates at a low speed. .

Also, when the wiper speed selection switch 5 is set to the high-speed operation position HIGH, the terminal HI of the switch 5 is
and E are electrically connected, so that the exciting coil 3'a of the first power relay switch 3' for high-speed operation is excited.

As a result, the switch portion 3'b is attracted against the return spring 3'e, and the terminals 3'f,
3'g, the main current flows from battery 1 to fuse 2 to first power relay switch 3'
Terminal 3'f, switch part 3'b, terminal 3'g
, to the H terminal of the wiper drive motor 6, so that the wiper drive motor 6 operates at high speed.

Furthermore, when the wiper speed selection switch 5 is set to the intermittent operation position INH, the terminal 7b of the interval wiper relay circuit 7 is grounded, and then, in conjunction with the action of the auto-stop mechanism 8, the capacitor C1 is charged and discharged, and the wiper drive motor 6 performs intermittent operation according to the intermittent time determined by this charging and discharging time. The details of the operation are almost the same as those of the first embodiment described above.

In Figure 2, symbols R7 and R8 are resistors, D5 and D6
indicates a diode, and 7f indicates a ground terminal of the electronic circuit 7, respectively.

As described in detail above, according to the main current indirect control type wiper drive circuit device of the present invention, the first power relay switch for high-speed operation is provided between the battery and the wiper drive motor 6, and the first power relay switch for low-speed operation is provided between the battery and the wiper drive motor 6. A second power relay switch is provided for both operation and intermittent operation, and the wiper speed selection switch is configured to indirectly control opening/closing of the main current flowing to the wiper drive motor through each of the power relay switches. With a simple configuration that is interposed in the circuit for turning on and off the excitation coils of the first and second power relay switches, the current flowing to the wiper speed selection switch can be reduced, thereby making it possible to select the wiper speed. In addition to making it possible to downsize the switch, there is an advantage that the switch can be easily arranged and stored.

Further, since the second power relay switch is configured as a switch for both low-speed and intermittent operation, there is an advantage that it can contribute to cost reduction.

[Brief explanation of the drawing]

FIG. 1 is an electric circuit diagram showing a main current indirect control type wiper drive circuit device as a first embodiment of the present invention, and FIG. 2 is an electric circuit diagram showing a main current indirect control type wiper drive circuit device as a second embodiment of the present invention. FIG. 2 is an electrical circuit diagram showing a drive circuit device. 1...battery, 2...fuse, 3,3'...
...First power relay switch, 3a, 3'a...
...excitation coil, 3b, 3'b...switch part,
3'c, 3'd... terminal, 3'e... return spring, 3'f, 3'g... terminal, 4, 4'... second power relay switch, 4a, 4'a... Excitation coil, 4b, 4'b...switch section, 4c...
...Exciting coil, 4d...Switch section, 4'e...
Return spring, 4'f, 4'g...terminal, 5
...Wiper speed selection switch, 6...Wiper drive motor, 7...Interval wiper relay circuit, 7a to 7f...Terminal, 8...Auto stop mechanism, 8a...Cam, 8b...Switch piece, 9...
... Washer switch, 10... Washer motor.

Claims (1)

[Scope of utility model registration request] In a wiper drive circuit in which the wiper drive motor can be selectively controlled between low-speed operation, high-speed operation, and intermittent operation by a wiper speed selection switch, a first power relay switch for high-speed operation is provided between the battery and the wiper drive motor. In addition, a second power relay switch is provided for both low-speed operation and intermittent operation, and the wiper speed is controlled to indirectly control opening and closing of the main current flowing to the wiper drive motor through each of the power relay switches. characterized in that a selection switch is interposed in a circuit for turning on and off the excitation coils of the first and second power relay switches;
Main current indirect control type wiper drive circuit device.