JPH05185906A - Window glass stain detecting device for vehicle - Google Patents

Abstract

PURPOSE:To maintain the visibility of a window glass in a good condition by making a judgement that the window glass is stained if the output signal value of a sensor when an ignition switch is turned on is in the specified value range between the signal value range when the rain drop is attached and the value in the cleaned condition, thereby actuating an alarm. CONSTITUTION:A rain drop sensor 13 outputs the signal of the level which is larger than the first specified value R1 in the non-stained condition of a window glass 11, and smaller than the second specified value R2 in the rain drop attached condition, and makes a judgement that the glass window is stained when the output level of the rain drop sensor 13 is in the 'stained' judgement zone (A) where the output level is higher than the second specified value R2 and lower than the third specified value R3. When a judgement is made that the window glass 11 is stained, a controller 15 drives a alarm lamp 40 and flashes it for a period T4 before the starter signal moves to the OFF- condition, i.e., before the engine is started, and alarming is made to inform a driver of the stained condition of the window glass 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a window glass stain detection device applied to an automatic wiper device or the like in a vehicle. In particular, a physical quantity sensor detects an optical physical quantity or an electrical physical quantity of the window glass, and the physical quantity is detected. The present invention relates to a window glass stain detection device that determines stains on a window glass based on the output of a sensor.

[0002]

2. Description of the Related Art In a vehicle equipped with an automatic wiper device, raindrops attached to a window glass are detected by a raindrop sensor, and the wiper is driven based on the output of the sensor. An automatic wiper device of this type is disclosed in JP-A-62-17.
As described in Japanese Patent No. 8459, etc., when a physical quantity such as electrostatic capacity of the window glass is detected and a change in the physical quantity of the window glass exceeds a predetermined value, a time when a considerable amount of raindrops adhere to the window glass Judge and drive the wiper.

[0003]

However, in the above-mentioned automatic wiper device, it is determined whether or not raindrops are attached based on the physical quantity of the window glass, the electrostatic capacity, etc. detected by the sensor. Therefore, if dirt is attached to the window glass, the physical quantity of the window glass also changes, and the amount of raindrops attached to the window glass cannot be accurately determined, and the operation of the wiper is affected. This invention has been made in view of the above problems,
We provide a window glass dirt detection device that can detect and notify the dirt of the window glass, prompt cleaning of the window glass, ensure correct operation of the auto wiper device, and also provide a view of the window glass with or without the auto wiper device. The purpose is to be able to keep in good condition.

[0004]

To achieve the above object, the present invention provides a physical quantity sensor for outputting a signal having a value corresponding to a physical quantity of a window glass, and an output signal value of the physical quantity sensor is set to an ignition. It is judged when the switch is turned on, and if the output signal value of the sensor when the ignition switch is turned on is within the predetermined value range between the signal value range when raindrops are attached and the clean value, it is determined that the window glass is dirty. Then, the alarm is activated.

[0005]

According to the present invention, the window glass is determined to be dirty when the output of the physical quantity sensor for detecting the physical quantity of the window glass is within the predetermined value range between the value when raindrops are attached and the value when it is clean. The stain on the window glass can be detected only when the raindrops are not attached, and the detection accuracy is not affected by the raindrops attached to the window glass. Further, since the determination of the stain on the window glass is made when the ignition switch is turned on, that is, when the vehicle is stopped, the notification is given, so that it is easy to take measures after cleaning or the like.

[0006]

Embodiments of the present invention will be described below with reference to the drawings. 1 to 3 show a vehicle window glass stain detecting device according to an embodiment of the present invention as applied to an auto wiper device, and FIG. 1 is an overall conceptual diagram of the auto wiper device,
2 is a timing chart for explaining the operation, FIG.
Is a characteristic diagram of the physical quantity sensor.

In FIG. 1, reference numeral 11 is a windshield of a vehicle.
1 includes a wiper mechanism 12 for wiping the outer surface and a raindrop sensor 13.
And are provided. Although detailed description and illustration are omitted, the wiper mechanism 12 is configured by attaching a blade to a wiper arm that is driven by the wiper motor 12b through the reduction mechanism, and the reduction mechanism is driven integrally with the blade by the wiper motor 12b and the blade is fixed. An actuation sensor 12a is provided which operates in position.

The wiper motor 12b has one end connected to the battery 16 via the ignition switch 19 and the other end grounded via the drive relay 14, and is energized by closing the contactor of the drive relay 14. Although detailed illustration is omitted, the operation sensor 12a is configured by sliding a brush connected to the battery 16 and a brush connected to the controller 15 with an electric plate having a notch formed in a part of the outer periphery thereof to be electrically connected. The plate rotates integrally with the arm to electrically connect and disconnect between the brushes. The operation sensor 12a outputs a pulse-like detection signal which becomes a low level (L) at a fixed position of the blade.

As is well known, the operation sensor 12
Although a functions as a switch that maintains power supply to the wiper motor 12b until the blade moves to a fixed position when the circuit is cut off, and also as a switch that causes the wiper motor 12b to perform electric braking at the fixed position, Since the function is well known, its illustration and description are omitted.

The raindrop sensor (physical quantity sensor) 13 is composed of, for example, an electrostatic capacitance type sensor which detects the amount of raindrops on the window glass surface by electrostatic capacitance, and is connected to the controller 15 (Japanese Patent Laid-Open No. 62-178459). No. The raindrop sensor 13 receives a pulse signal having a constant frequency from the controller 15 and converts the amount of raindrops or dirt adhering to the window glass into an impedance size and outputs it. When the dirt (raindrop quantity) is large, the raindrop sensor 13 outputs a low signal. level,
When the dirt is small, a high level signal is sent to the controller
Output to.

As shown in FIG. 3a, this raindrop sensor 13
The output signal of the level changes according to the amount of attached raindrops within the range of the first predetermined value R1 if the window glass is clean and the second predetermined value R2 if the raindrops adhere. As shown, the range A (R is smaller than the first predetermined value R1 and is larger than the third predetermined value R3 and is smaller than the second predetermined value R2.
3 ≦ A <R2) is set. In this embodiment, the second
The predetermined value R2 substantially coincides with the determination value of the raindrop sensor 13 when the auto wiper device starts operating in the auto mode.

The raindrop sensor 13 is not limited to the electrostatic capacitance type described above, and may be configured as described in JP-A-63-71461 or JP-A-61-37560. is there. And the raindrop sensor 1 described above
No. 3 is a physical quantity sensor in which the amount of attached raindrops (dirt) and the impedance (physical quantity) change in an inversely proportional characteristic (FIG. 3a), but the physical quantity to be detected and the raindrop quantity change in a proportional characteristic, for example, an optical sensor. It is also possible to use a sensor for detecting various physical quantities, and in the physical quantity sensor having such a proportional characteristic, the above-mentioned predetermined values R1, R2, R3 and the dirt determination area A are used.
Are defined in the relationship as shown in FIG. 3b.

Regarding the wiper mechanism 12 and the operation sensor 12a, not only the above-mentioned publication but also Japanese Unexamined Patent Publication No.
Since it is well known in the literatures such as 1-143247, JP-A-61-37560 and JP-A-62-289455, and automobile engineering complete books, the description thereof is omitted.

The controller 15 includes a microcomputer, a storage device, an A / D converter, a drive circuit and the like, and the battery 1 via the ignition switch 19.
6 is connected. The controller 15 is connected to a notification lamp 40 arranged near the driver's seat and a manually operable changeover switch 17, and the drive relay 1 described above is also connected.
4 connect. As will be described later, the notification lamp 40 is driven by the controller 15 and blinks when the window glass is dirty.

The drive relay 14 has a normally open contactor interposed between the wiper motor 12b and the ground, and a solenoid is connected to the controller 15. Also, the changeover switch 1
Reference numeral 7 has an auto mode position and a manual position, and any one position is alternatively selected by a manual operation. In addition,
These configurations are apparent from the above-mentioned publications and the like, and the description thereof will be omitted.

As will be described later in detail, the controller 15 detects the opening / closing of the ignition switch 19 depending on the presence or absence of power supply, determines the dirt on the window glass 11 when the ignition key is turned on, and drives the notification lamp 40. Further, the energization of the solenoid of the drive relay 14 is controlled based on the detection signals output from the operation sensor 12a and the raindrop sensor 13, the operation position of the changeover switch 17, and the like.

In this embodiment, the microcomputer is initialized when the ignition switch 19 is closed by turning on the ignition key and power is supplied from the battery 16 to the controller 15, and this initialization is continued. The dirt of the window glass 11 is determined, and when the window glass 11 is dirty, the alarm 55 is driven. Here, as shown in FIG. 2, the window glass 1
The stain detection and judgment of No. 1 are performed for a predetermined period T after a predetermined period T0 has elapsed since the ignition switch 19 was closed.
The period T1 is regulated so as not to exceed a predetermined period T3 from the time when the ignition switch 19 is closed. Then, in the period T1, the controller 15 reads each pulse amplitude of the pulse signal to be output, and the average value of these pulse amplitudes or the value obtained by smoothing the pulse signal in the period T1 is an impedance that is an electrical physical quantity, that is, the degree of contamination. Take in as.

Here, in this embodiment, as shown in FIG. 3a, the raindrop sensor 13 is larger than the first predetermined value R1 when the window glass 11 is not dirty, and the second predetermined value when the raindrop is attached. A signal having a level smaller than R2 is output, and when the output level of the raindrop sensor 13 is in the contamination determination area A that is equal to or greater than the second predetermined value R2 and equal to or less than the third predetermined value R3, it is determined that the raindrop sensor 13 is soiled. Therefore, the dirt on the window glass 11 can be detected without being affected by the presence or absence of raindrops attached, and the operation of the wiper, that is, the operation of the wiper motor 12b is not affected.

When it is determined that the window glass 11 is dirty, the controller 15 causes the notification lamp 4 to operate during the period T4 until the starter signal shifts to the OFF state, that is, the period T4 until the engine is started.
0 is made to blink and the window glass 11
Notify that the is dirty. Therefore, the driver or the like can know the dirt on the window glass 11 immediately after turning on the ignition key, that is, when the vehicle is stopped, and can easily take measures such as cleaning.

Further, in the subsequent normal operating state, as is well known, if the changeover switch 17 is operated to the automatic mode position and is set to the automatic mode, the raindrop sensor 13 has a capacitance as a physical quantity of the window glass 11. When the amount of change in the detection signal of the raindrop sensor 13 exceeds a predetermined value, it is determined that a considerable amount of raindrops has adhered to the window glass 11. At this time, the wiper motor 12b is energized for a predetermined time required for one reciprocating movement of the blade to wipe the window glass 11.

In the above-described embodiment, the embodiment applied to the vehicle auto wiper device is shown. However, not only the embodiment applied to the auto wiper device, but the present invention is independent of the auto wiper device by providing the physical quantity sensor separately. It goes without saying that it can be achieved by itself.

[0022]

As described above, according to the vehicle window glass dirt detecting device of the present invention, the physical quantity sensor detects the physical quantity of the window glass when the ignition key is turned on, and this physical quantity is used when raindrops are attached. Since it is determined that the window glass is dirty when it is within the range different from the physical quantity and it is notified, cleaning etc. can be performed when the vehicle is stopped, and it is easy to deal with the dirt.
In addition, stains when raindrops are not attached can be accurately detected, and the cost can be reduced by mounting the stain on the auto wiper device.

[Brief description of drawings]

FIG. 1 is a conceptual diagram of an auto wiper device to which a vehicle window glass stain detection device according to an embodiment of the present invention is applied.

FIG. 2 is a timing chart for explaining the operation of the window glass stain detection device.

3A and 3B show characteristics of a physical quantity sensor used in the same window glass detection device, FIG. 3A is a characteristic chart of the physical quantity sensor of one aspect, and FIG. 3B is a characteristic chart of the physical quantity sensor of one characteristic.

[Explanation of symbols]

11 ... Window glass, 12 ... Wiper mechanism,
13 ... Raindrop sensor (physical quantity sensor), 15 ... Controller, 19 ... Ignition switch, 4
0 ... Notification lamp (reporter).

Claims (1)

[Claims] 1. A physical quantity sensor for outputting a signal having a value corresponding to a physical quantity of the window glass is provided on the window glass, and the output signal value of the physical quantity sensor is judged when the ignition switch is turned on, and when the ignition switch is turned on. A vehicle window characterized in that if the output signal value of the sensor is within a predetermined value range between the signal value range when raindrops are attached and the value when clean, the window glass is determined to be dirty and an alarm is activated. Glass stain detector.