JPH0669036U - Automatic anti-glare water drop removal device for rearview mirror - Google Patents

Abstract

(57) [Abstract] [Purpose] Not only has an excellent automatic anti-glare function that can obtain a reflectance of any value as required,
(EN) Provided is an automatic anti-glare water droplet removing device for a rearview mirror, which simultaneously exhibits an excellent water droplet removing function capable of efficiently removing water droplets and the like on a mirror surface. A PLZT is arranged on a transparent substrate, a diaphragm is arranged on the back surface side of the transparent substrate, and a piezoelectric vibrator is fixed to the diaphragm.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to an automatic anti-glare water droplet removal device for a rearview mirror such as a door mirror or a fender mirror mounted on the outside of a vehicle cabin. In the present specification including the utility model registration claim, "automatic anti-glare water drop removing device" means a device having both the automatic anti-glare function and the water drop removing function of the rearview mirror. That is, the automatic anti-glare function prevents the annoyance and annoyance of reflected glare by reducing the reflectance of the rear-view mirror when the headlight light of the following vehicle is incident on the rear-view mirror while driving at night. The water drop removal function is a function that ensures good rear visibility by removing water drops that have adhered to the surface of the rear-view mirror while running in the rain.

[0002]

[Prior art]

 [Automatic anti-glare device] As a rearview mirror (anti-glare mirror) having an automatic anti-glare function, one in which the reflectance of the mirror is controlled by a liquid crystal or an electrochromic element, and one in which P LZT is used Are known. The anti-glare mirror using PLZT controls the reflectance of the mirror by utilizing a birefringence effect or a light scattering effect generated by applying a voltage to PLZT. Japanese Utility Model Laid-Open No. 58-190605 discloses an antiglare mirror that utilizes the birefringence effect of PLZT. In this antiglare mirror, as shown in FIG. 2, a PLZT plate 4 having comb-shaped transparent electrodes 2 and 3 on both front and back surfaces is arranged on the back surface side of the frontmost polarizing film 1, and the back surface of the PLZT plate 4 is arranged. A glass plate 6 having a reflective film 5 is arranged on the side. Reference numeral 9 in FIG. 2 is incident light. Japanese Utility Model Laid-Open No. 58-190604 discloses an anti-glare mirror utilizing the light scattering effect of PLZT. In this antiglare mirror, as shown in FIG. 3, a PLZT plate 14 having transparent electrodes 12 and 13 on both the front and back sides is arranged on the back side of the frontmost polarizing film 11, and the PLZT plate 14 is A glass plate 16 having a reflective film 15 is arranged on the back surface side. Reference numeral 19 in FIG. 3 is incident light. That is, in any of the antiglare mirrors shown in FIGS. 2 and 3, the PLZT plate is arranged on the front surface side of the glass plate.

[Water Drop Removal Device] As a rearview mirror having a water drop removal function, there is already known a rearview mirror that removes water drops attached to the surface of the mirror by using ultrasonic vibration. For example, in Japanese Utility Model Laid-Open No. 3-17960, as shown in FIG. 4, a piezoelectric vibrator 21 is fixed on a diaphragm 22, and a part of the peripheral edge of the diaphragm 22 is attached to the back surface of a mirror 23 with an adhesive 24. There is disclosed a water drop removing device which is adhered by means of. Reference numeral 29 is incident light. This device transmits ultrasonic vibration excited by the piezoelectric vibrator 21 to the mirror 23 via the vibration plate 22 and atomizes and removes water droplets attached to the surface of the mirror 23. In this case, since the space 25 is provided between the vibrating plate 22 and the mirror 23, the ultrasonic vibration excited by the piezoelectric vibrator 21 is transmitted from the peripheral portion of the mirror 23 via the vibrating plate 22. Be transmitted to.

[Automatic Anti-Glare Water Drop Removing Device] Further, Japanese Utility Model Laid-Open No. 3-6602, Japanese Utility Model Laid-Open No. 3-6603 and Japanese Utility Model Laid-Open No. 3-6604 disclose an automatic anti-glare function by an electrochromic element and ultrasonic vibration. Disclosed is an automatic anti-glare water droplet removal device having both of the water droplet removal functions according to the present invention. As shown in FIG. 5, in this device, an electrochromic layer 32 is provided on the back surface of the mirror 31, and the electrochromic layer 32 is covered with a protective layer 33. A space between the electrochromic layer 32 and the protective layer 33 is provided on the back surface of the mirror 31. A protective substrate 36 is attached via an adhesive 35 with the portion 34 formed, and an ultrasonic transducer 37 is attached to the back surface of the protective substrate 36. Reference numeral 39 is incident light. The water droplet removing function in this case is similar to that shown in FIG. 4, and the vibration generated by the ultrasonic transducer 37 is transmitted to the mirror 31 via the protective substrate 36 and the adhesive 35 and adheres to the surface of the mirror 31. It is designed to atomize water droplets.

[0005]

However, the above-mentioned conventional automatic anti-glare water droplet removal device using an electrochromic element has a drawback in that the reflectance of the mirror cannot be changed to an arbitrary value in terms of the automatic anti-glare function. is there. A similar problem is considered to occur when an automatic anti-glare water droplet removing device is configured by using liquid crystal instead of the electrochromic element. In addition, in the case of an automatic anti-glare water droplet removal device that uses a gel-type or liquid-type electrochromic element, the ultrasonic vibration is significantly attenuated by the electrochromic element, and the vibration is not efficiently transmitted to the mirror surface. There is a problem in terms of removal function. This is considered to be the same when an automatic anti-glare water droplet removal device is configured by using liquid crystal instead of the electrochromic element. The present invention has been made to solve the above problems and to provide an automatic anti-glare water drop removing device for a rearview mirror, which is excellent in both the automatic anti-glare function and the water drop removing function.

[0006]

[Means for Solving the Problems]

 In order to solve the above-mentioned problems, the present invention is characterized in that PLZT is arranged on a transparent substrate, a diaphragm is arranged on the back surface side of the transparent substrate, and a piezoelectric vibrator is fixed to the diaphragm. An automatic anti-glare water droplet removal device for a rearview mirror is provided (Claim 1).

It is desirable to dispose a heater panel between the transparent substrate and the diaphragm (claim 2).

It is desirable to seal the back surface of the PLZT electrode / reflection film with a protective film of Si ₃ N ₄ , SiO ₂ or the like (claim 3).

The PLZT is preferably a thin film having a thickness of 10 μm or less (claim 4).

It is desirable that a clearance be provided between the heater panel and the PLZT, the electrode / reflecting film or the protective film.

[0011]

[Action]

 [Automatic Anti-Glare Water Drop Removal Device for Rearview Mirror of Claim 1] PLZT is disposed on the back surface side of the transparent substrate. Therefore, PLZT is protected by the transparent substrate, and by using this as the substrate of PLZT, PLZT can be thinned. That is, for example, the PLZT thin film can be formed on the back surface of the transparent substrate by a sol-gel method, a vacuum deposition method, a sputtering method, a CVD method, an ion plating method or the like. Since PLZT is on the back surface of the transparent substrate and is protected by the transparent substrate, there is no problem in terms of durability and reliability even with such a thin film. As a result of making it possible to make PLZT thin, it is possible to reduce the weight of the vibrating body including PLZT. Therefore, the ultrasonic vibration excited by the piezoelectric vibrator is efficiently transmitted to the transparent substrate (mirror surface) via the vibrating plate, and the water droplets adhering to the surface of the transparent substrate are effectively atomized and removed. On the other hand, in terms of the automatic antiglare function, since PLZT is used as a means for changing the reflectance of the mirror, it is possible to change the reflectance of the mirror to an arbitrary value.

[Automatic Anti-Glare Water Drop Removing Device for Rearview Mirror of Claim 2] Water droplets with relatively large particles attached to the mirror surface can be atomized and removed by ultrasonic vibration as described above. If frost, ice, water droplets, or fog in the form of extremely fine mist adheres to the surface, it cannot be removed only by ultrasonic vibration. In such a case, if a heater panel arranged between the transparent substrate and the diaphragm is operated, a good field of view can be obtained in combination with ultrasonic vibration. That is, mist-like water droplets and cloudiness are removed in a short time by the heat generated by the heater panel. In addition, frost and ice are once turned into water droplets by the heat generated by the heater panel and then removed by ultrasonic vibration.

[Automatic Anti-Glare Water Drop Removal Device for Rearview Mirror of Claim 3] The electrode / reflection film of PLZT is sealed with a thin protective film such as Si ₃ N ₄ or SiO ₂ . Since this protective film is extremely light in weight as compared with conventionally used sealing materials such as glass plates, the efficiency of water droplet removal by ultrasonic vibration is improved. Also, there is no mirror distortion due to adhesion of this protective film. When the diaphragm is made of metal, the protective film prevents the drive voltage of the PLZT from leaking from the electrode / reflection film to the diaphragm.

[Automatic Anti-Glare Water Drop Removing Device for Rearview Mirror of Claim 4] When PLZT is formed as a thin film having a thickness of 10 μm or less, the water drop removing efficiency by ultrasonic vibration is further improved.

[Automatic Anti-Glare Water Drop Removal Device for Rearview Mirror of Claim 5] When a clearance is provided between the heater panel and the PLZT, electrode / reflecting film or protective film, the heater panel is PLZT, electrode / reflecting film or Since it does not come into contact with the protective film, damage to PLZT and the like due to frictional heat when ultrasonic vibration is applied is prevented.

[0016]

【Example】

Next, an embodiment of the present invention will be described with reference to FIG. Reference numeral 41 indicates a transparent substrate such as a glass plate. The PLZT 42 is arranged on the back surface side of the transparent substrate 41. The PLZT 42 is preferably a thin film having a thickness of 10 μm or less, and has a transparent electrode 43 on the front surface and an electrode / reflection film 44 on the back surface. The back surface of the electrode / reflecting film 44 is sealed with a protective film 45 such as Si ₃ N ₄ or SiO ₂ . A vibrating plate 47 is attached to the back surface side of the protective film 45 via an adhesive 46, and a piezoelectric vibrator 48 is fixed to the vibrating plate 47. Only the edge of the diaphragm 47 is bonded to the back surface of the protective film 45. In this structure, ultrasonic vibrations are transmitted from the edge of the mirror to the center of the mirror through the vibrating plate 47, so that water droplets can be atomized and removed from the entire surface of the mirror. The piezoelectric oscillator 48 is, for example, a piezoelectric ceramic oscillator such as PZT. In the case shown in FIG. 1, the piezoelectric vibrator 48 is fixed to the back surface of the diaphragm 47 with an adhesive 49. A heater panel 51 is attached to the vibrating plate 47 on the protective film 45 side through a polymer foam material 50 as an example. A clearance 52 is provided between the heater panel 51 and the protective film 45. Reference numeral 59 in FIG. 1 denotes incident light.

[0017]

[Effect of device]

 As described above, the automatic anti-glare water droplet removal device for the rearview mirror according to the present invention not only has the excellent automatic anti-glare function of being able to obtain a reflectance of any value as necessary, but also the mirror surface. At the same time, it has an excellent water drop removing function that can efficiently remove water drops and the like.

[Brief description of drawings]

FIG. 1 is a cross-sectional view showing an embodiment of the present invention.

FIG. 2 is a sectional view showing an example of a conventional automatic antiglare device.

FIG. 3 is a cross-sectional view showing another example of a conventional automatic antiglare device.

FIG. 4 is a cross-sectional view showing an example of a conventional water droplet removal device.

FIG. 5 is a cross-sectional view showing an example of a conventional automatic anti-glare water droplet removal device.

[Explanation of symbols]

 1 Polarizing Film 2 Comb Transparent Electrode 3 Comb Transparent Electrode 4 PLZT Plate 5 Reflective Film 6 Glass Plate 9 Incident Light 11 Polarizing Film 12 Transparent Electrode 13 Transparent Electrode 14 PLZT Plate 15 Reflective Film 16 Glass Plate 19 Incident Light 21 Piezoelectric Vibrator 22 Vibration Plate 23 Mirror 24 Adhesive 25 Space 29 Incident Light 31 Mirror 32 Electrochromic Layer 33 Protective Layer 34 Space Part 35 Adhesive 36 Protective Substrate 37 Ultrasonic Transducer 39 Incident Light 41 Transparent Substrate 42 PLZT 43 Transparent Electrode 44 Electrode / Reflective Film 45 Protective Film 46 Adhesive 47 Vibrating Plate 48 Piezoelectric Vibrator 49 Adhesive 50 Polymer Foam 51 Heater Panel 52 Clearance 59 Incident Light

Claims (5)

[Scope of utility model registration request] 1. An automatic anti-glare water drop for a rear-view mirror, wherein PLZT is provided on a transparent substrate, a diaphragm is provided on the back surface side of the transparent substrate, and a piezoelectric vibrator is fixed to the diaphragm. Removal device. 2. The automatic anti-glare water droplet removal device for a rear-view mirror according to claim 1, wherein a heater panel is provided between the transparent substrate and the diaphragm. 3. An automatic anti-glare water drop for a rear-view mirror according to claim 1, wherein the back surface of the electrode / reflective film for PLZT is sealed with a protective film such as Si ₃ N ₄ or SiO _2. Removal device. 4. The automatic anti-glare water droplet removal device for a rearview mirror according to claim 1, wherein the PLZT is a thin film having a thickness of 10 μm or less. 5. The automatic anti-glare water droplet removal of the rearview mirror according to claim 1, wherein a clearance is provided between the heater panel and the PLZT, the electrode / reflection film or the protective film. apparatus.