JPS5944641A - Liquid detector for automatic control device of wind shield wiper - Google Patents

Abstract

PURPOSE:To detect a raindrop, etc., and to control automatically a wiper, by providing a light emitting element and a photodetector at an angle for executing a total reflection when a raindrop, etc. are not adhering onto the outside face of a wind shield, and supporting them as one body to the inside face by a light transmitting material. CONSTITUTION:A liquid detector 20 is provided with a supporting body 21 consisting of a material having the same refractive index as that of a wind shield 10, a light emitting element 22, a photodetector 23 and a cover 24. The detector 20 is made to adhere to a part of an inside face 10b corresponding to a sliding area on an outside face 10a of the wind shield 10, and a light emitting shaft of the light emitting element 22 is placed in a direction for executing a total reflection when a raindrop, etc. are not adhering. A thin plate 25 is made of aluminum and light is subjected to a total reflection. Whether a raindrop, etc. are adhering to the outside face of the wind shield 10 or not can be detected by the quantity of light which is made incident to the photodetector 23, and the wiper is controlled automatically.

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 of a vehicle, aircraft, ship, 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 shield wiper automatic control device.

Conventionally, this type of liquid detector is 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 the wiper blade constituting the windshield wiper, and includes a light emitting element and a light receiving element. When there is no liquid such as raindrops attached to the outer surface of the windshield, the light emitted from the light emitting element is incident on the windshield so as to be completely reflected within the windshield, and the Ha liquid is The light receiving element receives the light emitted from the windshield after reflection inside the windshield, and the light reception result is transmitted to the windshield. Some devices are designed to generate detection signals necessary for automatic wiper control.

However, in such a liquid detector, conventionally, the work of fixing the light emitting element and the light receiving element to a part of the inner surface of the windshield is performed separately.
In addition, prior to such fixing work, the optical axis alignment between the light emitting axis of the light emitting element and the light receiving axis of the light receiving element must be properly performed in relation to the optical properties of the windshield. There was a problem in that it required more effort and time than necessary.

The present invention has been made in view of this problem, and its purpose is to include a support body formed from a light-transmitting material and fixed to a part of the inner surface of the windshield. An object of the present invention is to provide a liquid detector for an automatic windshield wiper control device in which two light-emitting elements and a light-receiving element are integrally supported in advance by a support.

Hereinafter, one embodiment of the present invention will be described with reference to the drawings.
The figure shows a liquid detector 20 according to the present invention assembled to a vehicle windshield 10. and a cover 24.The support body 21 is made of resin (for example, acrylic resin, polycarbonate I, or glass) having a refractive index that is substantially the same as the refractive index for light of the windshield 1 []. As shown in FIG.
It is formed by an integral molding method so as to be arranged symmetrically on both sides of c, and its lower surface 21d has a sliding surface 10/1 on the outer surface 10/1 of the windshield 10 of the wiper blade constituting the vehicle windshield wiper. It is adhered to a part of the inner surface iob of the windshield 10 corresponding to the dynamic area with a suitable transparent adhesive (having the same refractive index as the support 21).

A stepped hole 21θ is provided in the left protrusion 21a of the support body 21.
In the figure, the inclined shape shown in the figure is formed when the support body 21 is molded, and the light emitting element 22 is inserted into this stepped hole 21θ, and its base is fixed to the stepped portion of the stepped chair 1 hole 21e with epoxy resin. There is. In such a case, the inside of the hole 21e
The u-axis, that is, the light emitting axis of the light emitting element 220 is perpendicular to the bottom surface of the stepped hole 21e, and the normal line to the windshield outer surface 10a obtained at the intersection 10c of the light emitting axis with the windshield outer surface 10a and the light emitting element 22 The angle between the windshield 10 and the light emitting axis has a value between the critical angle of the windshield 10 with respect to air and the critical angle of the windshield 10 with respect to liquid such as rain. This means that when no liquid is attached to the windshield outer surface 1012, light emitted from the light emitting element 22 along its light emitting axis passes straight through the protrusion 21a of the support 21 into the windshield 10 and enters the outer surface 10a. When a total foul occurs and liquid 411 lands on a portion of the windshield outer surface 101 including the intersection 10c, the amount of light reflected at the intersection 10c decreases. The light emitting element 22 has a built-in near-infrared light emitting diode, and when the light emitting diode is turned on, it emits light in the form of a beam along its light emitting axis.

A thin plate 25 made of aluminum is attached to the center of the lower surface 21d of the support body 210 by a stamping method so as to be in close contact with the inner surface 1ob of the windshield. It functions to completely violate the rules. In addition, the right 1111 protrusion 21b of the support body 21 has a stepped hole 21f.
The stepped hole 21e is formed in the inclined shape shown in FIG. 1 at a position symmetrical to the point of incidence of light on the thin plate 25 when the support body 21 is molded. Light receiving element 2
6 is inserted and a stepped hole 2 is made with epoxy resin at its base.
It is fixed to the stepped portion of 1f. In such a case, step hole 21
The central axis of f, that is, the light receiving axis of the light receiving element 26 is the stepped hole 21f.
The direction of the light is perpendicular to the bottom surface of the support body 21 and coincides with the direction of light that travels straight into the protrusion 2Ib of the support body 21 after being deflected by the thin plate 25 and the outer surface 10a within the Winodo shield 10. The light-receiving element 26 has a built-in near-infrared photodiode, which is electrically connected by its receiver 'C' to generate a light-receiving signal.

The cover 24 is formed by a molding method using a light-resistant rubber or the like that does not transmit light, so as to have a cross section as shown in FIG. The light-emitting element 22 and the light-receiving element 26 are coated together, thereby shielding the light-receiving element 26 from ambient light and enhancing the external appearance of the liquid detector 20 itself. In addition, an insertion hole 2411 formed at the base of the cover 24
1 includes a lead wire 22 extending from the input terminal of the light emitting element 22 through the surface of the support 21 and the inner surface of the cover 24.
a is the lead wire 2 extending from the output terminal of the light receiving element 26;
6111 and is connected to the connector 26.

Note that the light emitting diode of the light emitting element 22 is connected to the connector 26.
Lead wire 22 from a control circuit (not shown) connected to
On the other hand, the photodiode of the light receiving element 26 transmits the received light signal to the control circuit through the lead wire 23a as a detection signal necessary for automatic control of the windshield soiper.

In this embodiment configured as above, the face piece detector 2
0 to the windshield 10, as described above, assemble the light emitting element 22 and the light receiving element 23 to the support 21, and attach the liquid detector 20 with the cover 24 removed from the support 21. Prepared in advance, the support 21 of the liquid detector 20 is attached to its lower surface 21d.
and then adhere to the windshield inner surface 10b as described above, and then cover the support 21 with the cover 24.
By only performing the above operations, the liquid detector 20 shown in FIG. 1 can be easily brought into the open state. In such a case, even if there is some distortion in the windshield outer surface 10d, the support body 21 will not bend the lower surface 21d due to its relationship with the thin wall portion 21c.
Therefore, it can be uniformly adhered to the windshield outer surface 10a regardless of its distortion. Note that since the support body 21 is an integrally molded component, there is no need to align the optical axes when the light emitting element 22 and the light receiving element 26 are assembled to the support body 21.

In addition, in carrying out the present invention, as shown in FIGS. 2 and 6, the left and right protrusions 21a of the support body 21.

Guide grooves 217 and 21h are formed along the top surface of the protrusion 21b and the opposing inclined surfaces of the protrusions 21a and 21b, respectively, and the lead wire 22/7 connected to the light emitting element 22 is guided through each guide groove 21.
．． The lead wire 2217 may be guided to the light-receiving element 26 by being placed within the respective guide grooves 21. Since the lead wires 22+7 are positioned by @ and 21h, this helps protect the lead wires 22+7 and facilitates the wiring work. However, this kind of thing still exists in the guide groove 21. y
, 21h may be omitted, or cover 2
4 has a guide groove 21. It can also be realized by providing a groove similar to @, 21h.

Further, in the above embodiment, the support body 21 was formed as an integrally molded component, but instead of this, as shown in FIG. One support part 21A, 21B is formed separately, and the cut-27 is attached to the thin part 21 of the support body 21.
The partition wall portion 27a corresponds to 4゛['' to C. It is formed with a structure that is added to the inner surface of the inner surface of the full cover 24, and both support parts 21A and 2113 are housed in the cover 27 in advance. Even if the lower surfaces of the parts 21A and 21B are bonded to the inner surface of the windshield, substantially the same effect as in the previous embodiment can be achieved. In this case, the partition wall 2 of the cover 27
By preparing a plurality of support parts 717 with different widths, the distance between the support parts 21A and 21B can be adjusted. Note that the lead wire 22a from the light emitting element 22 passes through the insertion hole 271 formed in the partition wall 27a of the cover 27 to the light receiving element 23.
(It is sufficient to guide the user to 1+11.

In the above embodiment, the light-emitting element 22 and the light-receiving element 26 are each described as being single, but the present invention is not limited to this, and a plurality of light-emitting elements 22 and light-receiving elements 26 may each be arranged in a row. In such a case, the shapes of the support body 21 and the cover 24 may be changed in accordance with the arrangement of the pixel elements 22 and 23.

As explained above, the liquid detector for a windshield wiper automatic control device according to the present invention employs a support made of a diaphragm that transmits through the forehead, as exemplified in the above embodiment, and Since both the light emitting element and the light receiving element constituting the liquid detector are integrally supported in advance, when the liquid detector is installed on the inner surface of the windshield, the support body must be placed at a suitable position on the inner surface of the windshield. It is only necessary to fix the pear, and it is possible to easily perform pear cultivation without causing the problems mentioned at the beginning of this specification.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view showing a liquid detector according to the present invention installed at a proper position on the inner surface of a windshield, FIG. 2 is a cross-sectional view showing a modification of the liquid detector in FIG. 1, and FIG. are a partially cutaway view of the modified example in Fig. 2, and Fig. 4.
This figure is a sectional view showing another modification of the liquid detector in FIG. 1. Explanation of symbols 10... Windshield, 10a... Windshield outer surface, 10b... Windshield inner surface, 20
. . . Liquid detector, 21 . . . Support, 22 . . . Light emitting element, 26 . . . - Light receiving element. Applicant Nippondenso Co., Ltd. Agent Patent Attorney Teru Hase −

Claims (1)

[Claims] A wiper blade constituting a windshield wiper is provided on a part of the inner surface of the windshield corresponding to the sliding area on the outer surface of the windshield, and has a light emitting element and a light receiving element, and has a liquid such as raindrops on the outer surface of the windshield. When there is no attached liquid, the light emitted from the light emitting element is incident on the windshield so as to be totally reflected within the windshield, and when the attached liquid is present, the amount of light reflected within the windshield is reduced. a liquid detector configured to reduce the amount of light emitted from the windshield after reflection within the windshield, and to receive the light emitted from the windshield by the light receiving element, and to generate the result of the light reception as a detection signal necessary for automatic control of the windshield wiper; A support body formed of a material that transmits light and fixed to a part of the inner surface of the windshield is provided, and the light emitting element and the light receiving element are previously integrally supported by the support body. A liquid detector for a windshield wiper automatic control device.