JPH10311786A - Water drop detector and wiper system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To detect with high precision water drops adhered to a rainwater adhering face of window shield glass. SOLUTION: A first detection part 12 and a second detection part 14 are formed in a window shield glass 10. In the first detection part 12, flipping coating 18 is applied on the surface, and in the second detection part 14, a concave and convex surface 20 is formed on the surface. In the first and second detection parts 12, 14, semiconductor illuminance sensors 22, 24 are arranged, and when a difference between a detection value of the semiconductor illuminance sensor 22 and a detection value of the semiconductor illuminance sensor 24 is reduced, a controller 30 decides that water drops are adhered to a raindrop adhering surface of the window shield glass 10.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water droplet detecting device and a wiper system, and more particularly to a water droplet detecting device for detecting water droplets such as raindrops attached to a raindrop attaching surface of a window shield glass of a vehicle such as an automobile and the like. The present invention relates to a wiper system including a detection device.

[0002]

2. Description of the Related Art Conventionally, a vehicle such as an automobile operates a wiper device by detecting a light source in front of the vehicle when the vehicle is traveling in a situation where environmental illuminance is low and raindrops are small. One example is disclosed in JP-A-5-147.
No. 501, and the configuration disclosed in this publication will be described below.

As shown in FIG. 5, the vehicle 100 includes a light source detecting means 102, a raindrop detecting means, an environmental illuminance detecting means, and a control means. While the vehicle is traveling below,
In front of the vehicle, a light source 106 is
Is detected, the wiper device 104 is forcibly operated regardless of the operation cycle. As a result, it is possible to pass through the location of the light source 106 in a state where the raindrops on the surface of the window shield glass 108 on which the raindrops adhere (the surface serving as the outer surface of the vehicle compartment) are wiped in advance, so that irregular reflection (glare) due to the light from the light source 106 is prevented. This does not occur, and sufficient forward visibility is ensured.

[0004]

However, in such an apparatus, the wiper cannot be operated properly unless water droplets such as raindrops and fog adhered to the raindrop adhesion surface of the window shield glass are reliably detected. Therefore, a highly accurate water droplet detection device is desired.

In view of the above, an object of the present invention is to provide a water drop detecting device and a wiper system capable of accurately detecting water drops adhering to a raindrop adhering surface of a window shield glass.

[0006]

According to a first aspect of the present invention, there is provided a water drop detecting device according to the present invention, wherein a first detecting portion of the windshield glass has a flat raindrop attaching surface, and the raindrop attaching surface of the first detecting portion. A first light detecting means provided on the back side of the windshield glass, a second detecting section in which the raindrop attaching surface of the windshield glass is uneven, and a second light detecting section provided on the back side of the raindrop attaching surface in the second detecting section. When the difference between the detection value of the second light detection means provided and the detection value of the first light detection means and the detection value of the second light detection means becomes small, water droplets adhere to the raindrop adhesion surface of the windshield glass. And water drop adhesion determining means for determining that the water droplet has adhered.

Accordingly, when no water droplets adhere to the raindrop attaching surface of the windshield glass, the incident light is scattered in the second detecting portion having the uneven surface, so that
The amount of light received by the second light detecting means is small. On the other hand, when water droplets adhere, the incident light is not scattered even in the second detecting portion having the uneven surface, so that the amount of light received by the second light detecting means is increased, and the amount of light received by the first light detecting means is increased. Is smaller. Based on this, the water droplet adhesion determining means determines that the water droplet has adhered to the raindrop adhesion surface of the windshield glass. For this reason, a water drop adhering to the raindrop adhering surface of the window shield glass can be accurately detected.

According to a second aspect of the present invention, in the water drop detecting device according to the first aspect, a water-repellent coating is applied to a raindrop-adhering surface of the windshield glass including at least the first detection unit, excluding the second detection unit. It is characterized by having been subjected to.

Therefore, when a water droplet adheres, the water droplet adheres to the first detecting portion which has become a flat surface by the water-repellent coating. As a result, the difference between the amount of light received by the first light detecting means and the amount of light received by the second light detecting means disposed on the second detecting unit having the uneven surface on which water droplets adhere in a granular manner is further reduced. Water droplets adhering to the raindrop adhering surface of the window shield glass can be detected with higher accuracy.

According to a third aspect of the present invention, the wiper system according to the present invention is provided on a first detecting portion of the windshield glass having a flat surface on which raindrops adhere and a rear surface of the first detecting portion on the rear surface side of the raindrop attaching surface. A first light detecting means, a second detecting unit having a windshield glass with a raindrop adhering surface formed as an uneven surface, and a second light detecting unit disposed on the back side of the raindrop adhering surface in the second detecting unit. Means for judging that water droplets have adhered to the raindrop adhering surface of the windshield glass when a difference between a detection value of the first light detection means and a detection value of the second light detection means has become small. Means, and a water drop removing device for removing water drops adhered to the raindrop adhering surface of the windshield glass, wherein the waterdrop adhesion determining means comprises: Determines that water droplets adhered, and the detection value of the first light detecting means is characterized in that when a predetermined value, activating the water droplet removal device.

Therefore, when no water droplets adhere to the raindrop attaching surface of the windshield glass, the incident light is scattered in the second detecting portion having the uneven surface, so that
The amount of light received by the second light detecting means is small. On the other hand, when water droplets adhere, the incident light is not scattered even in the second detecting portion having the uneven surface, so that the amount of light received by the second light detecting means is increased, and the amount of light received by the first light detecting means is increased. Is smaller. Based on this, the water droplet adhesion determining means determines that the water droplet has adhered to the raindrop adhesion surface of the windshield glass. In addition, when a water droplet adheres to the raindrop adhesion surface of the windshield glass and the detection value of the first light detection means has reached a predetermined value, that is, when diffuse reflection (glare) is likely to occur, the water droplet removal device operates. Therefore, irregular reflection (dazzle) due to light from the vehicle external light source can be reliably and efficiently prevented, and visibility can be sufficiently ensured.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of a water drop detecting device and a wiper system according to the present invention will be described with reference to FIGS.

In each of the drawings, an arrow FR is shown in front of the vehicle.
The upper part of the vehicle is indicated by an arrow UP.

As shown in FIG. 3, the windshield glass 10 of the vehicle according to the present embodiment is of a two-wiper wiping type, and a first detection unit 12 and a second detection unit 12 are provided at the lower center of the windshield glass 10 in the vehicle width direction. The detection unit 14 is formed. Further, the first detection unit 12 and the second detection unit 14 are set at positions close to each other in the wiping area of the wiper arm 16 on the left side of the vehicle (right side in FIG. 3).

As shown in FIG. 1, in a first detecting section 12 of a windshield glass 10, a transparent glass section 1 is provided.
A water-repellent coating 18 is applied to the surface of 0A (the surface on which raindrops adhere). On the other hand, in the second detection unit 14, an uneven surface 20 is formed on the surface of the transparent glass portion 10A (the surface on which the raindrops are attached) by frost processing. It has the property of retaining soaring fog drops. Note that the water-repellent coating 18 is applied to the entire surface of the windshield glass 10 including at least the first detection unit 12 except for the second detection unit 14.

In the first detection section 12 of the windshield glass 10, a semiconductor illuminance sensor 22 as first light detection means is provided on the back side (inside of the vehicle compartment) of the transparent glass section 10A, and the second detection section is provided. In the section 14, a semiconductor illuminance sensor 24 as a second light detecting means is disposed on the back side (inside of the vehicle compartment) of the transparent glass section 10A. The semiconductor illuminance sensor 22 and the semiconductor illuminance sensor 24 have the same specifications.

As shown in FIG. 2, the semiconductor illuminance sensor 2
2 and the semiconductor illuminance sensor 24 have a directivity (detection axis L) above the horizontal axis H by a predetermined angle θ,
Using a cylindrical case, a lens, a prism, and the like, the structure is such that external light is condensed on a built-in detection element. Note that the mounting angle of the semiconductor illuminance sensor 22 and the semiconductor illuminance sensor 24 may be inclined upward such that the detection axis of the detection element is directed upward by a predetermined angle θ with respect to the horizontal axis H.

As a result, the semiconductor illuminance sensor 22 and the semiconductor illuminance sensor 24 are not affected by the headlight of another vehicle.

As shown in FIG. 1, the semiconductor illuminance sensor 2
2 and the semiconductor illuminance sensor 24 are each a control device 3 having a microcomputer as water droplet adhesion determining means.
0, and when the difference between the detection value of the semiconductor illuminance sensor 22 and the detection value of the semiconductor illuminance sensor 24 becomes small, the control device 30 causes water droplets to adhere to the raindrop adhesion surface of the windshield glass. Is determined.

A wiper switch 32 and a wiper device 32 including a wiper arm, a link mechanism, a motor, and a drive circuit as a water droplet removing device are connected to the control device 30. 3
2 is activated.

Next, the operation of the present embodiment will be described with reference to the flowchart of FIG. In the present embodiment, the control device 3
According to 0, the following processing is performed. First, in step (hereinafter referred to as S) 200, the wiper switch 34
It is determined whether or not the dedicated mode for performing the following processing is set. If it is determined that the wiper switch 34 is set to the dedicated mode, in step S202, the detection value Sa of the semiconductor illuminance sensor 22 and the semiconductor Illuminance sensor 24
It is determined whether the difference between the detected value Sb and the detected value Sb is small, that is, whether the detected value Sa is substantially equal to the detected value Sb.

This is because if water drops do not adhere to the raindrop adhering surface of the windshield glass 10, light is irregularly reflected by the uneven surface 20 in the second detector 14, so that the detection value Sb of the semiconductor illuminance sensor 24 is small. Become. As a result, the detection value Sa of the semiconductor illuminance sensor 22 is
4 because the difference between the detected value Sa and the detected value Sb is larger than the detected value Sb of No. 4, ie, the difference returns to S200.

On the other hand, when water drops adhere to the windshield glass 10 and the uneven surface 20 of the second detecting section 14 becomes transparent and the light is no longer irregularly reflected, the detection value Sa of the semiconductor illuminance sensor 22 decreases. It becomes substantially equal to the detection value Sb of the semiconductor illuminance sensor 24, and the difference becomes smaller.

In S202, the semiconductor illuminance sensor 22
If it is determined that the detection value Sa of the semiconductor illuminance sensor 24 is substantially equal to the detection value Sb of the semiconductor illuminance sensor 24, it is determined in S204 whether the detection value Sa of the semiconductor illuminance sensor 22 is equal to or greater than a threshold value S1 stored in the control device 30 in advance. Is determined.

This is for judging whether or not there is a risk that the light amount from a light source external to the vehicle such as a street lamp may cause dazzling. The light amount is compared with a preset threshold value S1 (lower limit value). If it is determined that the value is equal to or greater than S1, in S206, it is determined whether the detection value Sa of the semiconductor illuminance sensor 22 is greater than a threshold value S2 stored in the control device 30 in advance.

This is for determining whether or not the amount of light from the external light source of the vehicle reaches dazzling.
Whether the light amount is large as in the daytime or the light amount is small as in the dazzling dusk or at night is compared with a preset threshold value S2 (upper limit value), and is determined to be smaller than the threshold value S2. In this case, in S208, the wiper device 32
It is determined whether or not the wiper device 32 is operating based on the output signal from.

If it is determined in S208 that the wiper device 32 is not operating, in S210, a wiper operation signal is output to the wiper device 32 to operate the wiper arm only once. As a result, the raindrop-adhering surface of the windshield glass 10 is wiped by the wiper arm, so that irregular reflection (glare) due to light from the vehicle external light source can be reliably and efficiently prevented, and visibility can be sufficiently ensured.

In S212 following S210, a timer is started and a predetermined time (for example, about 2 seconds) is set.
After returning to S200, the output of the wiper operation signal during the operation of the wiper is prevented.

As described above, in the present embodiment, when no water droplets adhere to the raindrop attaching surface of the windshield glass 10, the incident light is scattered in the second detecting portion 14 having the uneven surface 20. The semiconductor illuminance sensor 2
4 is small, but when a water droplet adheres, the incident light is not scattered even in the second detection unit 14 having the uneven surface 20, so that the light reception amount of the semiconductor illuminance sensor 24 increases, The difference from the amount of light received by the semiconductor illuminance sensor 22 disposed in the one detection unit 12 is reduced. Based on this, the control device 30 determines that water droplets have adhered to the raindrop adhering surface of the windshield glass 10, so that the controller 30 determines whether waterdrops have adhered to the raindrop adhering surface of the window shield glass 10. Water droplets can be accurately detected.

In this embodiment, when the water droplets 40 adhere to the raindrop adhesion surface of the window shield glass,
The water droplets 40 adhere to the uneven surface 20 of the second detection unit 14 in a granular manner, and the water droplets 40 also adhere to the first detection unit 12 in a granular manner by the water-repellent coating 18. As a result, the amount of light received by the semiconductor illuminance sensor 22 and the
Since the difference from the received light amount becomes smaller and almost equal to each other, the raindrop adhering to the raindrop adhering surface of the window shield glass 10, fog soaring from the road, and water droplet such as dew can be detected with higher accuracy.

In this embodiment, since the same semiconductor illuminance sensor can be used for the semiconductor illuminance sensor 22 and the semiconductor illuminance sensor 24, the configuration of the apparatus is simplified. Further, the semiconductor illuminance sensor 22 can be used as a light sensor and a sunshine sensor.

In the above, the present invention has been described in detail with respect to a specific embodiment. However, the present invention is not limited to such an embodiment, and various other implementations are possible within the wiping range of the present invention. It is clear to a person skilled in the art that forms are possible. For example, in the present embodiment, the semiconductor light intensity sensor is used as the first light detection means and the second light detection means, but the first light detection means and the second light detection means are not limited to the semiconductor light intensity sensors.

Further, in the present embodiment, the first detection unit 12 and the second detection unit 14 are formed at the center lower end of the windshield glass 10 in the vehicle width direction, but the first detection unit 12 and the second detection unit 14 The formation position is not limited to this part, and may be another part.

Further, in the present embodiment, in the second detecting section 14, the uneven surface 20 is formed directly on the surface of the glass transparent portion 10A. However, instead of this, another light-transmitting member having the uneven surface, For example, a configuration in which a resin tape or the like having an uneven surface is provided on the surface of the glass transparent portion 10A may be adopted.

[0035]

According to the first aspect of the present invention, there is provided a water drop detecting apparatus according to the present invention, wherein a first detecting section of a windshield glass having a flat raindrop adhering surface and a rear side of the first detecting section having a raindrop adhering surface are provided. A first light detecting means, a second detecting part having a windshield glass with a raindrop adhering surface formed as an uneven surface, and a second light detecting means disposed on the back side of the raindrop adhering surface in the second detecting part. Water drop adhesion determining means for determining that water droplets have adhered to the raindrop adhesion surface of the windshield glass when the difference between the detection value of the first light detection means and the detection value of the second light detection means has decreased. Therefore, there is an excellent effect that water droplets adhering to the raindrop adhering surface of the window shield glass can be accurately detected.

According to a second aspect of the present invention, in the water drop detecting device according to the first aspect, a water-repellent coating is applied to a raindrop-adhering surface of the windshield glass including at least the first detecting unit except for the second detecting unit. In addition, there is an excellent effect that water droplets attached to the raindrop attachment surface of the window shield glass can be detected with higher accuracy.

According to a third aspect of the present invention, there is provided a wiper system comprising: a first detection unit having a plane on which a raindrop is attached in a windshield glass; and a second detection unit disposed on the back side of the raindrop attachment surface in the first detection unit. A first light detection unit, a second detection unit in which a raindrop attaching surface of the windshield glass has an uneven surface, a second light detection unit disposed on a back surface side of the raindrop attachment surface in the second detection unit, A waterdrop adhesion determining means for determining that a waterdrop has adhered to the raindrop adhering surface of the windshield glass when a difference between the detection value of the light detection means and the detection value of the second light detection means has become small. Device, and a water droplet removal device that removes water droplets attached to the raindrop adhesion surface of the windshield glass, wherein the waterdrop adhesion determination means determines that waterdrops have adhered to the raindrop adhesion surface of the windshield glass, and (1) When the detection value of the light detecting means reaches a predetermined value, the water droplet removing device is operated, so that the water droplet attached to the raindrop attaching surface of the window shield glass can be accurately detected and the visibility is sufficiently improved. It has an excellent effect that it can be secured.

[Brief description of the drawings]

FIG. 1 is a schematic configuration diagram partially showing a cross section of a main part of a water droplet detection device and a wiper system according to an embodiment of the present invention.

FIG. 2 is a sectional view taken along line 2-2 in FIG. 3;

FIG. 3 is a front view showing a main part of a water droplet detecting device and a wiper system according to an embodiment of the present invention, as viewed from the front of the vehicle.

FIG. 4 is a flowchart illustrating control of a water droplet detection device and a wiper system according to an embodiment of the present invention.

FIG. 5 is a schematic diagram showing a relationship between a vehicle to which a wiper device according to a conventional embodiment is applied and an external light source.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Windshield glass 10A Glass transparent part 12 1st detection part 14 2nd detection part 16 Wiper arm 18 Water-repellent coating 20 Irregular surface 22 Semiconductor illuminance sensor (1st light detection means) 24 Semiconductor illuminance sensor (2nd light detection means) 30 Control device (water droplet adhesion determination means) 32 Wiper device (water droplet removal device) 34 Wiper switch

Claims (3)

[Claims] 1. A first detection unit having a plane on which a raindrop is attached on a windshield glass, a first light detection unit disposed on the back side of the raindrop attachment surface in the first detection unit, and the window A second detection unit in which the raindrop-adhering surface of the shield glass has an uneven surface; a second light detection unit disposed on the back surface side of the raindrop-adhesion surface in the second detection unit; When the difference between the detection value and the detection value of the second light detection means is small, water drop adhesion determination means for determining that water droplets have adhered to the raindrop adhesion surface of the windshield glass. Water drop detector. 2. The water drop detection device according to claim 1, wherein a water-repellent coating is applied to a raindrop attachment surface of the windshield glass including at least the first detection section except for the second detection section. 3. A first detecting unit in which a raindrop attaching surface is flat in the windshield glass; a first light detecting means disposed on a back surface side of the raindrop attaching surface in the first detecting unit; A second detection unit in which the raindrop-adhering surface of the shield glass has an uneven surface; a second light detection unit disposed on the back surface side of the raindrop-adhesion surface in the second detection unit; When the difference between the detection value and the detection value of the second light detection unit is small, a water droplet adhesion determination unit that determines that a water droplet has adhered to the raindrop adhesion surface of the windshield glass; A water droplet removing device that removes water droplets attached to the raindrop attaching surface of the windshield glass, wherein the waterdrop attachment determining unit determines that waterdrops have adhered to the raindrop attaching surface of the windshield glass, and Wiper system, characterized in that the detection value of the first light detecting means when a predetermined value, activating the water droplet removal device.