JP2001151080A - Wiper drive system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a wiper drive system for a wiper device that has an appreciably simplified circuit configuration using fewer components. SOLUTION: A first relay Ry1 used for intermittent wiper operations is forced into an ON position even during low-speed and high-speed wiper operations, and ON-OFF control action of a second relay Ry2 switches over an excitation circuit for low-speed or high-speed drive of a wiper motor 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wiper drive system having a simplified circuit structure with a reduced number of components in a wiper device.

[0002]

2. Description of the Related Art Generally, a wiper device in a vehicle is provided with a function of performing a wiping operation at a low and a high wiping speed, a function of performing an intermittent wiping operation, a washer function of performing wiping while spraying cleaning water onto a window, and the like. I have. As a drive motor (wiper motor) of such a wiper device, for example, a DC motor is used, and the operation is switched and selected by a wiper switch to drive the wiper. Further, a drive control circuit is provided to intermittently operate the wiper. As this drive control circuit, by charging and discharging with a capacitor,
In general, the relay is turned on and off by intermittently operating a relay to supply and control a drive current to a wiper motor. By the way, in the above-described wiper device, when the wiper motor is switched to operate at high speed / low speed, two relays each of a dedicated relay for high speed and a dedicated relay for low speed are used in addition to the relay for intermittent operation. In general, a control is performed via a relay without passing a current of a wiper motor directly to a wiper switch.

[0003]

Therefore, it is difficult to reduce the size because three relays are used, including those for intermittent operation, and it is also difficult to reduce the manufacturing cost. The present invention has been proposed to solve such a problem, and an object of the present invention is to provide a wiper drive system having a simplified circuit configuration with a reduced number of components in a wiper device.

[0004]

SUMMARY OF THE INVENTION In order to solve the above-mentioned problems, the present invention provides a wiper drive system, comprising: a switch body for switching a circuit for performing a high-speed operation, a low-speed operation, and an intermittent operation of a wiper; A wiper motor, and a wiper drive control circuit, wherein the wiper drive control circuit includes:
By switching the circuit by the switch body to perform the intermittent operation, the transistor is switched by charging and discharging the capacitor, the first relay is intermittently driven, and the drive current to the wiper motor is controlled. In order to perform high-speed operation and low-speed operation of the wiper, the switch body is switched to intermittently drive the second relay to switch an energizing circuit for high-speed driving and low-speed driving of the wiper motor, and to operate the wiper at high speed or low speed. In this case, the circuit is switched by the switch body, the transistor is forcibly turned on, the first relay is continuously operated, and the second relay is turned on, so that the wiper motor is driven at a high speed. Second
By turning off the relay, the energizing circuit that drives the wiper motor at low speed is switched.

[0005]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a wiper driving system according to the present invention will be described with reference to the accompanying drawings. FIG. 1 shows a wiper drive system in a vehicle. The wiper drive system includes, as an example of a switch, a rotary operation knob on the distal end side of an operation lever, which is provided in a combination switch disposed near a steering wheel (not shown) at an upper end of a steering shaft (not shown). By operating a switch and a push button (not shown), a function of switching a wiper (Hi), a wiper (Lo), an intermittent operation (INT.), A washer, and the like is performed.
In this wiper drive system, the wiper (H
i), the circuit configuration and functions relating to the wiper (Lo) and the intermittent operation (INT.) will be mainly described, and the circuit configuration and functions relating to the washer are not intended by the present invention, and therefore description thereof will be omitted. Shall be.

The wiper drive system has a switch body 1 whose contacts are switched by switching operation knobs, rotation changeover switches, and push buttons of the operation lever, a wiper motor 2, and a wiper drive control circuit 3. ing. The switch body 1 switches the movable contact by switching operation of an operation lever of an operation lever, a rotation changeover switch, and a push button, and controls a wiper (Hi), a wiper (Lo), an intermittent operation (INT.), And a washer. WASHER, INT, LOW,
It has HIGH and OFF operation positions.
The wiper motor 2 has a Lo terminal and a Hi terminal, and the wiper motor 2 is driven at a low speed and a high speed by switching and connecting the brush C and these terminals. A wiper blade is attached to an output shaft (not shown) of the wiper motor 2, and an automatic stop switch 2a is provided in conjunction with the wiper blade. The wiper drive control circuit 3 controls the drive current to the wiper motor 2 by switching the operation position of the switch body 1 by switching operation of the operation lever, thereby controlling the drive of the wiper motor 2.

The intermittent operation of the wiper drive control circuit 3 will now be described. The wiper drive control circuit 3 causes the first transistor Tr1 and the second transistor Tr2 to perform a switching operation by charging / discharging of a capacitor (described later) disposed on the electrical board, and the first relay Ry
1 is intermittently driven to supply a drive current to the wiper motor 2. A second relay Ry2 for switching and closing a circuit for performing a wiper (Lo) and a wiper (Hi) operation is mounted on the electrical board. The emitters of the first transistor Tr1 and the second transistor Tr2 are connected via a diode D to the B terminal of the connector 4 and to the + side of the battery power supply together with the brush C of the wiper motor 2. One end of the coil of the second relay Ry2 is connected to the + side of the battery power supply via the diode D from the terminal B of the connector 4.

The emitter of the first transistor Tr1 is connected to the positive pole of the capacitor C1 and the resistor R1 is connected between the positive pole of the capacitor C1 and the base.
The base is connected to the negative pole side of the capacitor C1 via the resistor R2. The negative pole of the capacitor C1 is connected to a resistor R
3, connected in series with the anode side of the diode D, the cathode side of the diode D is connected to the terminal b side of the interrupter 5 of the first relay Ry1, and the terminal b of the interrupter 5 of the first relay Ry1 is connected to the connector The P terminal 4 connects to the O terminal of the automatic stop switch 2a of the wiper motor 2. The collector of the first transistor Tr1 is connected to the I terminal of the connector 4 via a resistor R4,
The I terminal of the connector 4 is connected to the I side of the switch body 1. Further, the collector of the first transistor Tr1 is connected to the base of the second transistor Tr2 via the resistor R5. A resistor R6 is interposed between the emitter and the base of the second transistor Tr2. The resistor R5 is connected to the L terminal of the connector 4 via the resistor R7. This resistor R7 is connected to the H terminal of the connector 4 via a diode D. The L terminal and the H terminal of the connector 4 are connected to the switch body 1 respectively.
L and H on the side.

Next, the collector of the second transistor Tr2 is connected to one end of the coil of the first relay Ry1. The other end of the coil of the first relay Ry1 is connected to the terminal E of the connector 4 which is connected to the ground. Further, the terminal a side of the interrupter 5 of the first relay Ry1 is connected to the E terminal of the connector 4 which is connected to the ground.
On the other hand, the common terminal O of the interrupter 5 is connected to the common terminal O of the interrupter 6 of the second relay Ry2.

In the second relay Ry2, the other terminal of the coil is connected to the H terminal of the connector 4. In the interrupter 6 of the second relay Ry2, the terminal a is connected to the MH terminal of the connector 4 and the terminal b is connected to the ML terminal of the connector 4. The MH terminal and the ML terminal of the connector 4 are connected to the wiper motor 2 respectively. Hi terminal,
Connected to Lo terminal.

In the wiper drive system described above, the operation knob, the rotation changeover switch, and the operation lever of the operation lever are provided.
By operating the push button, the contact of the switch body 1 is changed from OFF to INT, LOW, HIGH, WASH.
By switching to ER, the wiper blade can be operated in each operation mode.

First, the position of the switch body 1 is changed to OF.
When switching from F to LOW, L
And E are connected, the L terminal of the connector 4 is connected to the ground,
Since the base current of the second transistor Tr2 flows, the second
The transistor Tr2 turns on. As a result, the first relay Ry1 is forcibly excited, the interrupter 5 is switched to the terminal a side, and the O of the interrupter 6 of the second relay Ry2 is turned off.
Since the circuit to the Lo terminal of the wiper motor 2 is closed via the terminal, the terminal b, and the ML terminal of the connector 4, a current is supplied to the wiper motor 2, and the wiper motor 2 starts rotating at a low speed. The wiper blade is displaced together with the wiper motor 2, and the automatic stop switch 2a is linked to the wiper blade.

Next, the position of the switch body 1 is changed to LO
When switching from W to HIGH, H and E in the switch body 1 are connected, the H terminal of the connector 4 is connected to the ground, and the coil of the second relay Ry2 is also energized, so that the second relay Ry2 is excited and intermittently connected. The container 6 is switched to the terminal a side. At the same time, when the H terminal of the connector 4 is connected to the ground, the second transistor Tr is connected via the diode D.
2 base current flows to turn on the second transistor Tr2
As a result, the first relay Ry1 is also forcibly excited, the interrupter 5 is switched to the terminal a, and the second relay Ry1 is turned on.
Since the circuit to the Hi terminal of the wiper motor 2 is closed via the O terminal and the terminal a of the second interrupter 6 and the MH terminal of the connector 4, a current is supplied to the wiper motor 2 and the wiper motor 2 can be rotated at high speed. .

Further, when the switch body 1 is turned off, the second transistor Tr2 is turned off, and the interrupter 5 of the first relay Ry1 is switched to the terminal b side, and the interrupter 6 of the second relay Ry2 is also switched to the terminal b side. Switch. However, the wiper motor 2 does not stop while the O terminal and the S terminal of the interlocking auto stop switch 2a are in contact with each other, and continues to rotate by Lo rotation for a while. When the wiper blade comes to the stop position, that is, the retracted position, the O terminal of the auto stop switch 2a is connected to the brush C side, so that the current stops flowing, and at the same time, the armature coil of the wiper motor 2 is turned off by the brush C of the auto stop switch 2a. Terminal, P terminal of the connector 4, terminal b of the interrupter 5 of the first relay Ry1, b, O
Terminal, the O terminal of the interrupter 6 of the second relay Ry2, the terminal b,
A short circuit is established between the ML terminal of the connector 4 and the Lo terminal of the wiper motor 2, and the brake is applied to the wiper motor 2.
Will stop suddenly. As described above, by switching the position of the switch body 1 from LOW to HIGH, the second relay Ry2 is turned ON, and the wiper motor 2 is turned on.
Is switched from the circuit to the Lo terminal to the circuit to the Hi terminal of the wiper motor 2, that is, the switching of Hi and Lo is performed on the make side and the break side of one relay. At the same time, a situation in which Lo and Hi are energized, that is, a situation in which the motor coil between Hi and Lo is short-circuited can be avoided.

When the wiper motor 2 is stopped, the terminal B of the connector 4, the capacitor C1,
Since the power is connected to the power supply through the resistor R2, the diode D, and the P terminal of the connector 4 via the auto stop switch 2a in the wiper motor 2, the capacitor C1 is in a discharged state. Under this condition, the wiper is operated intermittently (INT)
The switch body 1 is switched to connect I and E. Then, the I terminal of the connector 4 is grounded through the switch body 1, and the base current of the first transistor Tr1 is set to the resistor R1, the resistor R2, the resistor R3, the diode D,
An attempt is made to pass through the P terminal of the connector 4 and the auto stop switch 2a. However, in the auto stop switch 2a, the current cannot flow while the brush C side and the O terminal side are in contact, and as a result, the first transistor Tr1 is turned off.
It becomes F. Therefore, the base current of the second transistor Tr2 flows, and the second transistor Tr2 is turned on. As a result, the coil of the first relay Ry1 is energized and the first relay Ry1 is turned on.
When y1 is excited, the interrupter 5 is switched to the terminal a side, and is connected to the E terminal of the connector 4 which is connected to the ground. On the other hand, since the interrupter 6 of the second relay Ry2 is still connected to the terminal b, a current is supplied to the Lo terminal of the wiper motor 2 through the ML terminal of the connector 4 and starts rotating at a low speed. With the rotation of the wiper motor 2, the wiper blade is displaced, and the auto stop switch 2a also moves.
Is switched from the brush C side to the S terminal side, and the O terminal side is at the ground potential.

As a result, the P terminal of the connector 4 also has the ground potential, so that the base current of the first transistor Tr1 flows, and the first transistor Tr1 is turned on. At the same time, charging of the capacitor C1 is started. When the first transistor Tr1 is turned on, the base current of the second transistor Tr2 stops flowing, the first relay Ry1 is demagnetized, and the interrupter 5 switches to the terminal b. However, the wiper motor 2 is connected to the second relay Ry from the ML terminal side of the connector 4.
2 through the terminal b and the O terminal of the interrupter 6 and the terminal 4 of the first relay Ry1 through the terminal b of the interrupter 5.
While the auto stop switch 2a is in contact with the S terminal via the P terminal, the current of Lo rotation flows, so that the wiper motor 2 continues to rotate. Then, the contact of the automatic stop switch 2a is switched from the S terminal side to the brush C side by the rotation of the wiper motor 2. As a result, the armature coil of the wiper motor 2 moves from the brush C of the auto stop switch to the O terminal and the connector 4.
P terminal, terminal b and O terminal of the interrupter 5 of the first relay Ry1, O terminal and terminal b of the interrupter 6 of the second relay Ry2, ML terminal of the connector 4, Lo terminal of the wiper motor 2 and a short circuit. The brake is applied, the wiper motor 2 stops suddenly, and the wiper blade stops at a predetermined position. In this state, since the capacitor C1 has been charged, a discharge current flows from the capacitor C1 as a base current of the first transistor Tr1, and the first transistor Tr1 is kept ON and maintained. Is OFF because the base current cannot flow, and the first relay Ry1 remains OFF, and this state is maintained. Therefore, the wiper blade remains stopped. Then, when a predetermined time (intermittent time) has elapsed, the discharge of the capacitor C1 is completed, the base current of the first transistor Tr1 stops flowing, and the first transistor Tr1 is turned off. This turns on the second transistor Tr2,
The interrupter 5 of the first relay Ry1 switches to the terminal a side, and the wiper motor 2 starts to rotate again. The intermittent operation can be performed by repeating the above operation.

Here, when the switch body 1 is switched to switch the wiper from intermittent operation (INT) to LOW, L and E in the switch body 1 are connected, the base current of the second transistor Tr2 flows, and the second transistor Tr2
Is turned on, the first relay Ry1 is turned on, and a circuit for energizing the Lo terminal of the wiper motor 2 is formed, and the wiper motor 2 rotates by Lo rotation. However, connector 4
Since the I terminal of the switch body 1 is open, the first transistor Tr1 remains OFF.
Therefore, there is no intermittent operation due to charging and discharging of the capacitor C1. Therefore, when the wiper motor 2 rotates by Lo rotation,
Since the O terminal of the auto stop switch 2a of the wiper motor 2 repeatedly contacts the brush C side or the S terminal side, the capacitor C1 repeats charging and discharging. Is in contact with the brush C only when it is at the stop position.
The time when the terminal is in contact with the S terminal is much longer than the time when the terminal is in contact with the C terminal, and it can be said that the capacitor C1 is in a charged state.

[0018]

As described above, according to the present invention, the first relay provided at the time of the intermittent operation of the wiper is forcibly turned on even at the time of low-speed and high-speed operation of the wiper, and the second relay is turned on. / OFF operation to switch the energizing circuit for low-speed driving or high-speed driving of the wiper motor, so that the number of parts is reduced.
It can be realized as a wiper drive system with a more simplified circuit configuration. Moreover, the wiper motor operates at high speed,
Alternatively, the switching of the energizing circuit for low-speed driving is switched on the make side and the break side of one relay, so that a short circuit of the motor coil can be avoided.

[0019]

[Brief description of the drawings]

FIG. 1 is a circuit configuration diagram showing an example of a wiper drive system according to the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Switch body 2 Wiper motor 2a Auto stop switch 3 Wiper drive control circuit 4 Connector 5, 6 Interrupter

Claims (1)

[Claims] 1. A wiper drive system, comprising: a switch main body configured to switch a circuit for performing a high-speed operation, a low-speed operation, and an intermittent operation of a wiper; a wiper motor; and a wiper drive control circuit, wherein the wiper drive control circuit is provided. By switching the circuit by the switch body to perform the intermittent operation, the switching operation of the transistor is performed by charging and discharging the capacitor, the first relay is intermittently driven, and the driving current to the wiper motor is controlled. ,
In order to perform high-speed operation and low-speed operation of the wiper, the switch body is switched to intermittently drive the second relay to switch an energizing circuit for high-speed driving and low-speed driving of the wiper motor, and to operate the wiper at high speed or low speed. In this case, the circuit is switched by the switch body, the transistor is forcibly turned on, the first relay is continuously operated, and the second relay is turned on, so that the wiper motor is driven at a high speed. A wiper drive system characterized by switching an energizing circuit for driving a wiper motor at a low speed by turning off a second relay.