JPS59178338A - Liquid detector for automatic control apparatus of windshield wiper - Google Patents

Abstract

PURPOSE:To enhance detection accuracy by preventing the mixing-in of an error caused by disturbance light, by providing a light emitting element constituting a liquid detector to the inner surface of a windshield while providing a light receiving element above the light emitting element. CONSTITUTION:A light receiver 40 is secured to a front glass inner surface 10b so as to position above a light emitter 20 in such a state that the light receiving axis thereof is directed downwardly and beam light upwardly emitted from the light emitter 20 is received along the light receiving axis by the light receiver 40. Therefore, even if direct rays of the sun are incident to the front glass 10, they can not transmit a prism 43 from the bottom surface thereof toward a first flat surface, a semiconductor light receiving element 41 is prevented from receiving direct rays of the sun and a receiving signal is not accompanied by the error caused by direct rays of the sun while, even if beam light is emitted from a car running on the opposite lane during night running, it is not directly incident to the light receiver 40 and an error is not caused thereby. In addition, even if beam light is incident to the semiconductive light receiving element 41, this situation does not result in an error because of the difference in a wavelength.

Description

[Detailed Description of the Invention] The present invention relates to a windshield wiper automatic control device,
In particular, a windshield that uses photoelectric conversion to detect the adhesion of liquid such as raindrops on the outer surface of the windshield wiper of vehicles, aircraft, ships, etc., and generates this detection result as a detection signal necessary for automatic control of the windshield wiper. This invention relates to a liquid detector for a wiper automatic control device.

Conventionally, this type of liquid detector has been provided, for example, on a part of the inner surface of the windshield corresponding to the sliding area on the outer surface of the windshield of a wiper blade constituting a windshield wiper, and on a part of the inner surface of the windshield that corresponds to the sliding area on the outer surface of the windshield. The light emitted from the light emitting element described in item ()11 is transmitted to the outer surface of the wind seal 1-' when liquid such as raindrops (
= When the J is not landing, all the fouling is caused within the windshield, and when the I\J landing liquid is present, the amount of fouling within the windshield is reduced. Let people be disciplined;
and the light-receiving element receives the light emitted after reflection within the windshield (windshield wiper) and generates a light-receiving signal, and generates the light-receiving signal as a detection signal necessary for automatic control of the windshield wiper. There is something like this.

However, in such a liquid detector, the light-emitting element and the light-receiving element are usually provided on a part of the inner surface of the wind seal 1-' with their respective light-emitting axes and light-receiving axes oriented horizontally, and the light-receiving element is Since the light-receiving area and the light-receiving direction are spread out, this light-receiving element receives not only the light from the light-emitting element reflected from the windshield and emitted from the inside, but also 1i U·1 sunlight and other disturbance light. This causes an error in the received light signal.

The present invention was made in response to the above-mentioned problems, and its purpose is to provide a light-receiving element adopted in a liquid detector of an automatic windshield wiper control device.
The purpose is to provide the windshield on a part of the inner surface of the windshield in a direction that makes it difficult to receive direct sunlight and other disturbance light.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
The figure shows a state in which a liquid detector S for a vehicle windshield wiper automatic control device according to the present invention is attached to a windshield 1o of the vehicle, and each wiper blade 11 of the windshield wiper. 12 is each wiping area 11a on the outer surface 10a of the windshield 1°
, 12a are slidably disposed.

The liquid detector S is located in the wipe area 11a of the wiper blade 11.
It is attached to the upper part of the inner surface 10b of the windshield 1o corresponding to a part of the windshield 1o, and is composed of a light emitter 201, a reflective thin plate 60, and a light receiver 40 (see FIGS. 1 and 2). The light emitter 20 includes a semiconductor light emitting element 21, a convex lens 22, and a lens J126, and the prism 26 has a refractive index (
n=1.52), and is fixed to the windshield inner surface 101) at the bottom surface 25a opposite to its apex angle (FIGS. 2 and 6, f316). . In such a case, the line of intersection formed by the first and second planes 25b and 23C of the prism 26 at the apex angle of the prism 26 is horizontal and
It is parallel to 1). Note that in FIGS. 1 and 2, reference numerals 16 and 14 respectively indicate the hood and roof of the vehicle.

The semiconductor light emitting device 21 has its light emitting axis aligned with the first one of the prism 23.
i″!l: is arranged so as to intersect the plane 2b and face the first plane 231) through the convex lens 22,
Windshield outer surface 10 of the light emitting axis of the semiconductor light emitting element 21
The angle θ between the light emitting axis of the semiconductor light emitting device 21 and the normal to the windshield outer surface 10a determined at the intersection point 10C (see FIG. 6) with ) in relation to the critical angle (approximately 4
1.1°), the water on the windshield 10° (
ff has a refractive index of −1,66)). However,
When the semiconductor light emitting element 21 emits light along the light emitting axis due to its conduction, if there are no raindrops adhering to the area including the intersection 10C of the windshield outer surface 10a, light is emitted from the semiconductor light emitting element 21 and the convex lens 22 and prism 23. The light entering the windshield 10 through the outer surface 1 [1a
It is totally reflected in the area including the intersection point 10C. Also,
When raindrops are attached to the area including the intersection 10C, the amount of light emitted from the semiconductor light emitting element 21 in the area including the intersection 10C decreases depending on the adhesion state of the raindrops. Note that the convex lens 22 converts the light from the semiconductor light emitting element 21 into a parallel beam of light, and converts it into a parallel beam of light.
The thin plate 60 is made of a material such as aluminum, and is affixed to a part of the inner surface 10b of the windshield directly above the prism 26. Light emitter 2 reflected in the area including the intersection 10c of the inner surface 10a
It functions to completely submerge the beam light from 0 to 1. The light receiver 40 is reflected by the anti-fouling thin plate 60, and then the fluorocarbon j
- In the area including the point 10d on the outer surface of the glass (located in a symmetrical position with respect to the intersection point 10C with reference to the anti-IJ = 1 point of light to the anti-M, I thin plate 60), the windshield is 1
In order to receive the beam light emitted upward from 0,
It is installed in a part of the inner surface of the windshield 10b at a position directly above the non-conforming thin plate 60 and symmetrical to the light emitter 20 with respect to the point of incidence of light onto the non-conforming thin plate 60 as a reference. This light receiver 40 includes a semiconductor light receiving element 41, a convex lens 4
2 and a prism 46, the prism 4
6 is formed of the same material size as the prism 26, and is fixed to a part of the inner surface of the windshield 10b at the bottom surface 43/l opposite to the apex angle thereof. In this case, the line of intersection formed by the first and second planes r143b and 43c of the prism 46 at the apex angle of the prism 46 is horizontal and parallel to the inner surface 1[1b of the windshield].

The semiconductor light receiving element 41 has its light receiving axis aligned with the first one of the prism 46.
The light is disposed perpendicular to the first plane 43b and faces the first plane 43b through the convex lens 42, and is reflected from the windshield 10 in an area including the point 10d on the outer surface 10.2 of the windshield 10. The emitted light beam is received through a prism 46 and a convex lens 42 to generate a light reception signal. Note that the convex lens 42 functions to condense the light beam emitted from the first plane 43b of the prism 46 onto the light receiving surface of the semiconductor light receiving element 41. Further, the semiconductor light emitting element 21 is made to conduct and emit light in response to a drive pulse from a light emission control circuit (not shown), while the light reception signal from the semiconductor light receiving element 41 is processed by a signal processing circuit (not shown) into the windshield. Wiper (7) Converts into a detection signal necessary for automatic control.

In this embodiment configured as described above, the light receiver 40
is fixed to the inner surface of the windshield 10b with its light-receiving axis facing downward and located on the side of the light emitter 20, and receives the beam light 41+ in the direction from the light emitter 20.
Since the light is received along the light receiving axis, even if one light is directly incident on the windshield 10, this 1σ sunlight is transmitted through the prism 46 from the 1rc 4372 to the 1st dot 43b. As a result, the semiconductor winding element 41 does not receive direct sunlight.
Even if a beam of light is emitted from the headlamp of a car headed for 71 when traveling directly to the receiver υ without any error due to 1 chance, the traveling direction of this beam light is normally 1 unit. Since the light receiving direction of the light receiver 40 is still facing the top surface of the bonnet 16, the beam light from the 01J head lamp is not directly directed to the light receiver 40, and the semiconductor light receiving element 41 There is no error in the received light signal due to beam light from the headlights of an oncoming vehicle. 'f:, d, In such a case, even if the beam light from the bed lamp in the 4] direction
10 Since the emission wavelength is different, the semiconductor light receiving element 41
It almost never causes an error in the light reception signal from the oncoming vehicle, and if you want to take the worst case into consideration, it is recommended to install an appropriate filter on the light receiving surface of the semiconductor light receiving element 41 to block the beam light from the oncoming vehicle. Just leave it as .

In the above embodiment, the light receiver 4o is replaced by the light emitter 20.
Although an example has been described in which the light receiver 4° is disposed directly above the light emitter 2o, the present invention is not limited thereto. ) may be fixed to a part of the area.

In such a case, the present invention is not limited to the windshield 10 of a vehicle, and the present invention may be applied to the rear glass of a vehicle, the windshield of a ship, etc. by attaching the present invention.

As explained above, in the waste liquid detector of the windshield wiper automatic control device according to the present invention, as exemplified in the above embodiment, the light emitting element constituting the liquid detector is A light-receiving element forming the liquid detector is provided on a part of the inner surface of the windshield so as to be oriented in the direction, and a light-receiving element forming the liquid detector is oriented within the windshield in the -1- direction. The feature of the structure is that it is provided on a part of the inner surface of the windshield above the light emitting element so as to receive the light from the light emitting element. , l) 'J MU light receiving element is not allowed to receive disturbance light of 1 light 1 and 1 light q downward from one side, and as a result, the light receiving element Errors caused by the disturbance light are not mixed into the light reception signal generated by the light reception, and the detection accuracy of this divine liquid detector can be improved.

[Brief explanation of the drawing]

FIG. 1 is a front view showing a state in which a liquid detector according to the present invention is attached to a windshield of a vehicle, FIG. 2 is a side view of the same, and FIG. 6 is a partially enlarged side view of the same. Explanation of No. 99 10...] I'J front glass, 10a... Outer surface of windshield, 10b... Inner surface of Freon 1-glass,
2B... Light emitter, 21... Semiconductor light emitting element, 22° 42... Convex lens, 23.43... Prism, 40
... Light receiver, 41... Semiconductor light receiving element. Applicant Nippondenso Co., Ltd. Agent Patent Attorney Teru Hase - Figure 1 z Figure 2 0 Figure 3 0

Claims (1)

[Claims] Provided on a part of the inner surface of the windshield corresponding to the sliding area on the outer surface of the windshield of the wiper blade constituting the windshield wiper,
It has a light-emitting element and a light-receiving element, and is configured to completely reflect the light generated from the total light-emitting element described in II above within the windshield when no liquid such as raindrops is attached to the outer surface of the windshield. At the same time, when the above-mentioned (= J liquid amount exists), the amount of fouling is reduced in the IJ windshield 1-', and 1) the IJ light-receiving element ! J ArJ A liquid detector that receives light emitted from a windshield after fouling inside the windshield and generates it as a light reception signal, and generates this light reception signal as a detection signal necessary for automatic control of the windshield wiper, The light-emitting element is provided on a part of the inner surface of the windshield so that the light is emitted upward, and the light-receiving element is provided so that light from the light-emitting element is reflected from the windshield and emitted upward. A liquid detector for a windshield wiper automatic control device, characterized in that the liquid detector is provided on a part of the inner surface of the windshield above the light emitting element so as to receive light.