JPH0798476B2 - Wiper control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Overview A first operation mode of continuously driving a wiper blade,
The second operation mode, which is driven intermittently, is manually selected,
A wiper control device for reciprocally driving a wiper blade by selectively supplying power to at least two types of power input terminals for low speed and high speed of a driving means so as to achieve the selected operation mode. A second control means is interposed between the control means and the drive means, and the second control means detects the rainfall based on the output of the raindrop detection means when the first control means is selected in the second operation mode. A so-called auto wiper function can be added by supplying power to the low speed power source input terminal of the drive means so as to be in an operating state corresponding to the state, and thus adding the second control means to the first control means. it can.

Further, the second control means is energized by the electric power to be supplied from the first control means to the low speed power supply input terminal of the driving means, and accordingly, during the pause and high speed operation of the wiper operation. The second control means does not energize the electric power, whereby the basic operation of the wiper is ensured even when the second control means fails, and so-called fail safe is realized.

INDUSTRIAL APPLICABILITY The present invention controls wiper operation in response to rainfall conditions,
The present invention relates to a so-called auto wiper control device, and more particularly to a configuration for adding an auto wiper function to a wiper control device that does not have the auto wiper function.

Conventional technology In an existing wiper control device that does not have an auto wiper function, in order to downsize the device, a wiper switch that selects the operation mode of the wiper and a control circuit that performs the wiper operation according to the setting state of the switch. And are arranged on one printed circuit board and are integrally formed. In order to newly add an automatic wiper function to this wiper control device, it is detected that the wiper switch is set to the intermittent mode, and an intermittent period corresponding to the rainfall state detected based on the output of the raindrop sensor. And a new control circuit for controlling the wiper operation must be added.

However, since the existing control circuit and the wiper switch are integrated as described above, it is difficult to detect the setting state of the wiper switch from the outside. For this reason, in the typical prior art, a dedicated switch for the automatic wiper operation is separately added in addition to the configuration for the automatic wiper operation.

Therefore, in order to perform the automatic wiper operation, the existing wiper switch (manual operation) is set to the intermittent mode, and the dedicated switch of the newly added auto wiper is operated. There is a need to. Further, since the two switches are located at different positions, it is likely to cause confusion and the operability is poor.

In addition, in order to add a dedicated switch for the auto wiper,
There arises a problem that it is necessary to modify the vicinity of the added place, and furthermore, the exclusive switch of the added auto wiper and the existing wiper switch do not have the same shape.

An object of the present invention is to provide a wiper control device capable of adding an auto wiper function without adding a dedicated switch.

Means for Solving the Problems The present invention relates to a drive unit that reciprocally drives a wiper blade and includes at least two types of power input terminals for low speed and high speed, and a low speed for continuously driving the wiper blade at low speed. Operation mode and high-speed operation mode that drives continuously at high speed,
Multiple contacts that are in a switching state corresponding to the intermittent operation mode that is driven intermittently, and the external output terminal (+ 1a) common to the low-speed operation mode and the intermittent operation mode
And an external output terminal (+2
a), a first control means for selecting one of the operation modes by manually selecting the contact and selectively supplying power to each power input terminal of the driving means; and a raindrop for detecting raindrops. It is interposed between the detection means, the driving means and the first control means, outputs an identification signal to the first control means, and the switching state of the contact corresponds to either the low speed operation mode or the intermittent operation mode. A raining state in response to an identification result of the identifying means, and in response to an output of the raindrop detecting means when the first control means is set to the intermittent operation mode. And second control means for controlling the drive means so as to be in an operating state corresponding to, and continuously controlling the drive means at a low speed when the first control means is set to the low speed operation mode. Including Said second control means is a wiper control apparatus characterized by being by connexion biased in power supplied from the common external output terminal of said first control means (+ 1a).

Further, according to the present invention, the first control means is configured such that the impedance in the circuit changes according to the switching state of the contact, and the identification means derives the inspection pulse to the first control means. However, the switching state is detected based on the level change of the inspection pulse due to the impedance.

According to the present invention, the drive means for reciprocating the wiper is connected to the first control means, the drive means is directly driven, and the wiper is continuously reciprocally driven at a low speed.
A high-speed operation mode that continuously drives at high speed and an intermittent operation mode that intermittently drives the wiper can be switched by a manual operation to perform the operation, and an automatic wiper control function can be easily added. In order to be able to do so, the second control means to which the raindrop detection means is connected can be arranged so as to be interposed between the first control means and the drive means, thereby facilitating the function of the automatic wiper control. When the intermittent operation mode is set in the first control means, the wiper can operate in response to the raindrop detection means in response to the output of the raindrop detection means. The second control means is provided with identification means for identifying whether the control means is in the low speed operation mode or in the intermittent operation mode, and by the identification means, the intermittent operation is performed as described above. When the first control means is set in the operation mode, the automatic wiper control is enabled.

Further, according to the invention, the external output terminal (+ 1a) common to the low speed operation mode and the intermittent operation mode of the first control means
Therefore, power is supplied to the second control means, and accordingly, when the high speed operation mode, which is an operation mode other than the low speed operation mode and the intermittent operation mode, is set, power is not supplied to the second control means. Therefore, even when the second control means fails, the high-speed operation mode can be achieved, and fail-safe is realized.

Embodiment FIG. 1 is a block diagram showing the electrical construction of an embodiment of the present invention. Existing switch circuit 1 which is the first control means
When the wiper switch 11 is set to the INT mode which is the intermittent mode by interposing the control device 3 which is the second control means between the wiper motor 2 and the wiper motor 2, the raindrop sensor 4
The wiper blade is driven at the wiping interval corresponding to the rainfall state detected in step S1, and the automatic wiper operation is realized.

Therefore, in the existing wiper control device, the wiper motor 2
, The terminal + 1d connected to the low speed power input terminal P1 of the motor 21 is connected to the terminal + 1a of the switch circuit 1, and the terminal + 1d connected to the high speed power input terminal P2 is the terminal + 2a of the switch circuit 1. The terminal + Sd connected and connected to the common contact S2a of the cam switch 22 is connected to the terminal + Sa of the switch circuit 1.

The switch circuit 1 includes a wiper switch 11 and a circuit connected to the wiper switch 11 on one printed circuit board, and the potentials of the terminals + Sa, + 2a, + 1a corresponding to the setting modes of the wiper switch 11 are set. Changes.
The terminal + Ba is supplied with power from the battery 6 via the ignition key switch 5, and the terminal Ga is grounded.

The wiper switch 11 can be set to four operation modes of OFF, INT, LO and HI. The wiper operation is suspended when the PFF mode is set. When the INT mode, which is the second operation mode, is set, the wiper blade is driven at the wiping interval corresponding to the rainfall state. The wiper blades set in the first operation mode, LO mode and HI mode, are continuously driven, and are driven at a low speed in the OL mode and at a high speed in the HI mode.

In FIG. 1, the wiper switch 11 indicates the contact connection state in each of the above operation modes, that is, OF
In F mode, contacts +1 and + S become conductive and contact I
NT1 and contact B1 become conductive, and in INT mode, contact +1 and + S
And the contacts INT1 and INT2 conduct, the contacts + B and +1 conduct in the LO mode, and the contacts + B and +2 conduct in the HI mode.

When the wiper switch 11 is set to the OFF mode, the constant voltage circuit 30 in the control device 3 is connected to the terminal + 1b-terminal + 1a-contact + 1-contact + S-contact S1a-contact S1c-terminal +.
The voltage IG of the battery 6 through the ignition key switch 5 through the Sa-terminal + Sb-resistor R2-resistor R1-terminal + Bb.
However, in this state, due to the current limitation of the resistors R1 and R2, sufficient power for energizing the control circuit 31 that performs the auto wiper control operation is not supplied, and therefore the control circuit 31 is It goes into hibernation.

In the OFF mode, one terminal of the capacitor C1 via the resistors R1, R2, the other terminal is connected in parallel with the resistors R1a, R1b for setting the intermittent time, the resistors R1a, R1b, Since the voltage IG is almost applied through the resistor R1e having a resistance value smaller than the combined resistance value of the resistors R1a and R1b, the capacitor C1 is discharged.

Therefore, when the wiper switch 11 is set to the INT mode, the capacitor C1a is charged through the contact INT1−contact INT2−diode D1−resistor R1c, and the capacitor C1a is fully charged so that the terminal voltage is predetermined. When the voltage exceeds the value, the transistor Tr1 becomes conductive.

As a result, the relay coil L1 is excited, the relay switch S1 is switched, and the constant voltage circuit 30 is fed to the constant voltage circuit 30 via the terminal + Ba-contact S1b-contact S1a-contact + S-contact + 1-terminal + 1a-terminal + 1b. The voltage IG is supplied. When the power is thus applied, the control circuit 31 detects the switching state of the wiper switch 11 as will be described later, and based on the output from the raindrop sensor 4 via the waveform shaping circuit 34 when in the INT mode. Then, the auto wiper control operation is performed.

The resistor R1e is connected in parallel to the resistors R1b and R1a in the OFF mode as described above, and reduces the time constant for charging the capacitor C1. Therefore, Wye Pass Itch 11
Even if the capacitor C1 is once discharged as in the case where the setting mode of is switched to INT-OFF-INT, the capacitor C1 can be rapidly charged, and thereby the control circuit 31 can be quickly started up. .

The output of the control circuit 31 during the automatic wiper operation is led to the relay coils L3 and L4 via the diodes D3a and D4a, respectively. That is, when the low speed wiper is driven, the relay coil L3 is excited and the relay coil L4 is demagnetized. As a result, electric power from the battery 6 is supplied to the low speed power input terminal P1 of the motor 21 through the terminal + Bb-contact S3b-contact S3a-contact S4a-contact S4c-terminal + 1c-terminal + 1d. Further, when the high speed wiper is driven, both relay coils L3 and L4 are excited, and power is supplied to the high speed power supply input terminal P2 of the motor 21. Furthermore, at the time of intermittent, the relay coil
Both L3 and L4 are demagnetized.

When the wiper switch 11 is set to the LO mode, the voltage IG is supplied to the constant voltage circuit 30 via the terminal + Ba-contact + B-contact + 1-terminal + 1a-terminal + 1b. Thereby, the control circuit 31 is energized to detect the switching state of the wiper switch 11 as described later, and when the LO mode is set, the relay coil L3 is driven so as to continuously drive the motor 21 at a low speed. Hold in the excited state.

When the wiper switch 11 is set to the HI mode, no electric power is supplied to the constant voltage circuit 30, and the control circuit 31 is in a dormant state. However, power is supplied to the relay coils L3 and L4 via the terminals + Ba-contacts + B-contacts + 2-terminals + 2a-terminals + 2b-diodes D3b and D4b, and the relay coils L3 and L4 are excited. Contact S3b-Contact S3a-Contact
S4a-contact S4b-terminal + 2c-terminal + 2d
It is supplied to the high speed power input terminal P2.

The wiper motor 2 includes a motor 21 and a cam switch 22 that are integrated with each other, and the cam 23 of the cam switch 22 rotates in accordance with the wiper blade wiping position. In the stopped state of the motor 21 with the wiper blade in the rest position, the common contact S2a of the cam switch 22 is electrically connected to the individual contact S2c, and therefore the terminal + Sc of the control device 3 is the terminal + Sd-contact S2a.
It is connected to the terminal Gd, which is connected to the ground terminal PG of the motor 21, via the contact S2c, and is set to the ground potential. When the cam switch 22 rotates, for example, 30 degrees or more, the common contact S2a conducts to the individual contact S2b, so that the voltage IG of the battery 6 supplied to the terminal + Bd is derived from the terminal + Sd.

In the INT mode and the LO mode, the potential of the terminal + Sc of the control device 3 is read into the control circuit 31 via the processing circuit 32, and the control circuit 31 turns on the relay coil L3 during the wiping operation of the wiper blade. Excitation is continued to return the wiper blade to the rest position.

Also, when the wiper switch 11 is switched to the OFF mode in a state where the wiper blade is away from the rest position, the power supply to the control circuit 31 is cut off in the INT mode and the LO mode, and accordingly, via the diode D3a. The supply of the exciting current to the relay coil L3 is stopped, and the supply of the exciting current to the relay coils L3 and L4 via the diodes D3b and D4b is stopped in the HI mode, whereby the common contact S3a of the relay switch S3 is Conductive to individual contact S3c, and common contact S4a of relay switch S4 is individual contact S4c
Power is connected to the low speed power supply input terminal P1 of the motor 21 until the wiper blade returns to the rest position.

As mentioned above, the wiper switch 11 is in LO mode and INT.
When the mode is set, the control circuit 31 is energized via the constant voltage circuit 30, and therefore the control circuit 31 detects the switching state of the wiper switch 11 as follows, and when the INT mode is set, When the auto wiper control operation is performed and the LO mode is set, the motor 21 is continuously driven at a low speed.

FIG. 2 is a circuit diagram for explaining a connection state in the switch circuit 1 when the wiper switch 11 is set to the INT mode or the LO mode. A low-level pulse having a pulse width of 2 msec and a pulse interval of 200 msec, for example, is derived from the control circuit 31 as shown in FIG. 3A, and the pulse is realized by a transistor or the like.
After being inverted at 33, as shown in FIG.
It is derived from terminal + Sb via R2. This pulse is shunted to the relay drive circuit 18 including the diode D1, the resistors R1c and R1d, the transistor Tr1 and the like when the contacts INT1 and INT2 of the wiper switch 11 are conducting.

That is, as seen from an alternating current, when the LO mode is set, the pulse from the pulse generating circuit 33 is divided by the resistor R2 and the resistors R1b and R1a as shown in FIG. 4 (1). And appears at terminal + Sb. When the INT mode is set, as shown in FIG. 4 (2), the voltage is divided by the resistor R2, the resistors R1b and R1a and the combined impedance of the relay drive circuit 18, and appears at the terminal + Sb.

Therefore, the peak value VL in INT mode is shown in Fig. 3 (3).
As shown in FIG. 3, the value becomes small, for example, 1 V, while the peak value VH in the LO mode becomes high, for example, 3 V, as shown in FIG. 3 (4).

The setting mode of the wiper switch 11 can be read by comparing the peak values VL and VH with the predetermined reference voltage V _TH by the level discrimination circuit 35. The level discrimination circuit 35 is composed of, for example, a voltage dividing circuit, a comparator, and a reference voltage source. In the voltage divider circuit, if the input voltage is
The voltage is divided into 1/2 and the reference voltage V _TH is set to 1.1 V, for example.

In the above-described embodiments of FIGS. 1 to 4, it is not possible to determine which of the low speed operation mode and the intermittent operation mode is selected only by the switch circuit 1, and therefore, in the above-described embodiments of the present invention, the intermittent operation mode is selected. The function of auto wiper control responding to the output of the raindrop sensor 4 can be easily added by easily detecting the selection of the operation mode. That is, in a system in which it is not possible to determine which of the low speed operation mode and the intermittent operation mode is selected only by the first control means, it is possible to easily detect that the intermittent operation mode is selected and easily add the function of the aud wiper control. It was done like this.

That is, to explain with reference to FIG. 1, when the low speed operation mode is selected in the switch circuit 1 which is the first control means, a high level signal from the external terminal + 1a is transmitted via the contact + B → contact +1 of the wiper switch 11. Although it is output, even if the intermittent operation mode is selected, the external terminal + Ba → resistance
R1a, R1b → contact INT1 → contact INT2 → diode D1 → resistor R1c
→ Current flows through the path of the base of transistor Tr1 and transistor Tr1 turns on, relay coil L1 conducts, contact S1a connects to contact S1b, and external terminal + Ba →
A high level signal is output from the external output terminal + 1a via the contact S1b → contact S1a → contact + S → contact +1 (the external output terminal + 1a is always high level in the low speed operation mode, and high level and low level in the intermittent operation mode). Is output repeatedly).

As described above, in a system that does not have an external output terminal dedicated to the intermittent operation mode but has an external output terminal common to the low speed operation mode and the intermittent operation mode, it is not possible to immediately determine from the output state whether the operation mode is the intermittent operation mode.

Therefore, in the above-described embodiment, by providing the identification signal for outputting the identification signal to the first control means and identifying whether the switching state of the contact corresponds to the low-speed operation mode or the intermittent operation mode, Even when the first control means is configured to have a common external output terminal in the low speed operation mode and the intermittent operation mode, it is possible to easily detect whether or not the intermittent operation mode.

Thus, in the wiper control device according to the present invention, the control device 3 for adding the automatic wiper function is provided between the existing switch circuit 1 and the wiper motor 2, and the control device 3 controls the wiper switch in the switch circuit 1. It is possible to detect the 11 setting modes, and thus it is not necessary to provide a dedicated switch for the auto wiper separately from the existing wiper switch 11, and thus without causing any confusion to the operator, and the dedicated switch. No need to remodel with the addition of, the installation work can be simplified, and the aesthetic appearance is not spoiled.

Furthermore, the control circuit 31 that performs the auto wiper control operation,
Since the power is supplied only when the wiper switch 11 is in the INT mode and the LO mode, in the OFF mode and the HI mode, the control circuit 31 is put in the rest state, and the control circuit 31 is out of control or the raindrop sensor 4 is operated. It is possible to secure a fail-safe function in case of malfunction due to adhesion of dirt on the.

EFFECTS OF THE INVENTION As described above, according to the present invention, the function of the automatic wiper control can be easily added only by adding the second control means to the existing wiper control device having no automatic wiper function. Further, since the second control means automatically determines the setting state of the wire switch, it is not necessary to separately provide a control switch dedicated to the auto wiper, and the driver can easily operate the wiper and the troublesomeness is eliminated. .

Further, since it is not necessary to separately provide a dedicated switch on the auto wiper, the cost is reduced and the work of adding the auto wiper control is facilitated.

Further, according to the present invention, in the system which enables the first control means and the wiper reciprocating drive means to be directly connected to manually select and operate the low speed operation mode and the intermittent operation mode, The second control means is interposed between the control means and the drive means, the raindrop detection means is connected to the second control means, and the first control means does not have an external output terminal dedicated to the intermittent operation mode, and operates at low speed. In a system having an external output terminal (+ 1a) that is common to both the operation mode and the intermittent operation mode, it is not possible to immediately determine from the output state whether or not the operation mode is the intermittent operation mode. The identification signal is given from the means to the first control signal to discriminate between the low speed operation mode and the intermittent operation mode. Controls, the Otowaipa control to perform an operation in response to the output of the O connexion rain detection means to, upon detection of the intermittent operation mode of the first control means, it is possible to achieve.

Further, according to the present invention, since the second control means is configured to be supplied with power from the external output terminal (+ 1a) common to the low speed operation mode and the intermittent operation mode, even if the second control means fails, Even if occurs, it is possible to secure the basic operation of the wiper by supplying electric power from the external output terminal + 2a in the high speed operation mode to the drive means, and to realize the fail safe.

[Brief description of drawings]

FIG. 1 is a block diagram showing the electrical construction of a wiper control device according to an embodiment of the present invention, and FIG. 2 is a block diagram of a wiper switch 11 with INT.
Circuit diagram for explaining the connection state in the switch circuit 1 when the mode is set to LO mode or LO mode, FIG. 3 is a waveform diagram for explaining the inspection operation for reading the setting mode of the wiper switch 11, and FIG. The figure is an equivalent circuit diagram when a pulse is applied to the switch circuit 1. 1 ... Switch circuit, 2 ... Wiper motor, 3 ... Control device, 4 ... Raindrop sensor, 5 ... Ignition key switch, 6 ... Battery, 11 ... Wipe pass switch, 30 ...
Constant voltage circuit, 31 ... Control circuit, 32 ... Processing circuit, 33 ...
Pulse generation circuit, 34 ... Waveform shaping circuit, 35 ... Level discrimination circuit

Claims (2)

[Claims] 1. A drive means for reciprocally driving a wiper blade and having at least two types of power input terminals for low speed and high speed, a low speed operation mode for continuously driving the wiper blade at low speed, and a high speed operation mode. High-speed operation mode that drives continuously,
Multiple contacts that are in a switching state corresponding to the intermittent operation mode that is driven intermittently, and the external output terminal (+ 1a) common to the low-speed operation mode and the intermittent operation mode
And an external output terminal (+2
a), a first control means for selecting one of the operation modes by manually selecting the contact and selectively supplying power to each power input terminal of the driving means; and a raindrop for detecting raindrops. It is interposed between the detection means, the driving means and the first control means, outputs an identification signal to the first control means, and the switching state of the contact corresponds to either the low speed operation mode or the intermittent operation mode. A raining state in response to an identification result of the identifying means, and in response to an output of the raindrop detecting means when the first control means is set to the intermittent operation mode. And second control means for controlling the drive means so as to be in an operating state corresponding to, and continuously controlling the drive means at a low speed when the first control means is set to the low speed operation mode. Including Said second control means is a wiper control apparatus characterized by being by connexion biased in power supplied from the common external output terminal of said first control means (+ 1a). 2. The first control means is configured so that the impedance in the circuit changes according to the switching state of the contact, and the identification means derives an inspection pulse to the first control means. The wiper control device according to claim 1, wherein the switching state is detected based on a level change of the inspection pulse due to the impedance.