JP2530499Y2 - Water drop removal device for automotive outside mirror - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a water drop removing apparatus which vibrates an outside mirror of an automobile to simultaneously remove water drops adhering to the mirror when the vehicle is running on rainy weather and to prevent fogging.

[0002]

2. Description of the Related Art When driving a car in rainy weather, water drops adhere to a fender mirror or a door mirror.
If it is cloudy, the rear will be difficult to see, making it impossible to drive safely. Therefore, a piezoelectric element and a heater are joined to the back surface of the mirror plate, and the piezoelectric element bends and vibrates the mirror plate to induce a standing wave, thereby atomizing water droplets adhering to the surface of the mirror plate, and further heating the heater. There has been proposed a water droplet removing device which removes fogging by the heat generated by the water.

[0003]

[Problem to be solved by the invention] In the above-mentioned device,
The mirror plate generates standing waves due to bending vibration, that is, spot-like vibrations in which a vibration node (a point where the amplitude is substantially zero) and a vibration loop (a point where the amplitude is the largest) intersect. There is a drawback that it cannot be removed without difficulty, and there is also a drawback such as shortening the life of the battery because the heater generates heat.

[0004]

According to the present invention, in order to solve the above-mentioned drawbacks, an excitation piezoelectric element and a vibration receiving piezoelectric element for receiving vibration from the piezoelectric element are provided on a back surface of a mirror plate at a predetermined interval. At the same time, a load resistor connected to the piezoelectric element for receiving vibration is attached, and a traveling wave is induced by the piezoelectric element for excitation, whereby water droplets adhering to the surface of the mirror plate are moved and removed together with the traveling wave. At the same time, the surface of the mirror plate is prevented from being fogged by the heat generated by the load resistor.

[0005]

The driving action of the excitation piezoelectric element and the vibration reception of the vibration receiving piezoelectric element induce a traveling wave from the excitation piezoelectric element toward the vibration receiving piezoelectric element on the surface of the mirror plate. If water droplets adhere to the surface of the mirror plate, the water droplets move in the same direction on the traveling wave, collectively grow near the piezoelectric element for vibration reception, fall by their own weight and are removed from the mirror plate. Will be. Further, the load resistor connected to the piezoelectric element for vibration reception converts the electric energy of the piezoelectric element for vibration reception into heat energy and generates heat, and this heat is transmitted to the mirror plate to prevent fogging.

[0006]

FIG. 1 shows an embodiment of the present invention. Reference numeral 1 denotes a mirror plate incorporated in a fender mirror or a door mirror of an automobile, and is bonded to one end of the rear surface thereof with an adhesive or the like. The excitation piezoelectric element 2 and the vibration-receiving piezoelectric element 3 joined to the other end with an adhesive or the like. The piezoelectric elements 2 and 3 for excitation and vibration are provided with opposing electrodes 4 and 5 formed by baking silver on the front and back surfaces of a piezoelectric ceramic plate made of lead zirconate titanate or the like as shown in detail in FIG. Further, the same type of electrode in which the lead wire connection electrode 4a conducting to the inner electrode 4 joined to the mirror surface plate was extended to the outer electrode 5 side was used. An oscillation circuit source 6 is connected to the excitation piezoelectric element 2, and a load resistor 7 and a matching inductor 8 fixed to the back surface of the mirror plate 1 are inserted into the vibration receiving piezoelectric element 3 in electrical parallel. Have been. By appropriately selecting the values of the load resistor 7 and the matching inductor 8, the vibration receiving piezoelectric element 3 is a non-reflection terminal with respect to the mirror plate 1.

Next, the operation of the above example will be described. When an alternating voltage having a predetermined resonance frequency is applied to the excitation piezoelectric element 2 by the oscillation circuit source 6 and driven, the vibration is transmitted to the surface of the mirror plate 1 and proceeds. A wave S propagates from the position of the excitation piezoelectric element 2 toward the vibration receiving piezoelectric element 3. When a water droplet adheres to the surface of the mirror plate 1 in which the traveling wave is induced as described above, the water droplet moves along with the traveling wave, and the water droplet gathered near the piezoelectric element for vibration reception 3 becomes large. Is dropped by its own weight and removed from the mirror surface plate 1. On the other hand, the traveling wave S received by the vibration receiving piezoelectric element 3 is converted into electric energy,
Is converted into heat energy, and this heat is transmitted to the mirror plate 1 to prevent the surface from being fogged.

In the above example, in order to facilitate the connection of the lead wire to the inner surface of the piezoelectric element (the surface in contact with the mirror plate), the relay electrode is extended from the electrode and formed on the outer electrode side.
When such a relay electrode is omitted, a conductive layer larger than the outer shape of the piezoelectric element is formed on the surface of the mirror plate by plating, vapor deposition, or the like, and the piezoelectric element is attached to the conductive layer and exposed from the outer periphery of the element. Alternatively, a lead wire may be connected to the portion to be connected.

In the present invention, in addition to the above embodiment, as shown in FIG.
And a pair of vibration receiving piezoelectric elements 3 and 3 are disposed at both ends to induce a traveling wave S from the excitation piezoelectric element 2 toward the vibration receiving piezoelectric elements 3 and 3 on both sides. The waves S can transfer water droplets adhering to the surface of the mirror plate 1 and remove it from the surface of the mirror plate. In this case,
The effect of removing water droplets can be further enhanced.

[0010]

As described above, according to the present invention, a traveling wave is induced on the surface of the mirror plate, and the traveling wave removes and removes water droplets adhering to the surface of the mirror plate. Since the surface of the mirror plate is also de-fogged by the heat generated by the load resistor that converts it to heat energy, it is compared with a conventional water-removing device that removes water droplets using standing waves and uses a heater to prevent fogging. Because it can remove water droplets and fogging neatly, it is possible not only to provide an outside mirror that makes it easy to check backwards and safely, but also to prevent fogging without using a heater that consumes a lot of power. This also has the effect of extending the life of the battery.

[Brief description of the drawings]

FIG. 1A is a front view of a back side of a water droplet removing device according to an embodiment of the present invention.

FIG. 1B is a side sectional view of the water droplet removing device shown in FIG. 1A.

FIG. 2 is a perspective view showing a form of an excitation piezoelectric element and a vibration receiving piezoelectric element used in the embodiment of FIG.

FIG. 3A is a front view of a back side of a water droplet removing device according to another embodiment of the present invention.

FIG. 3B is a side sectional view of the water droplet removing device shown in FIG. 3A.

[Description of Signs] 1 Mirror surface plate 2 Exciting piezoelectric element 3 Piezoelectric receiving element 7 Load resistor

Claims (3)

(57) [Scope of request for utility model registration] 1. A load connected to a piezoelectric element for excitation and a piezoelectric element for vibration for receiving vibration from the piezoelectric element at a predetermined interval on a back surface of a mirror plate, and connected to the piezoelectric element for vibration reception. A resistor is attached, and a traveling wave is induced on the surface of the mirror plate by the piezoelectric element for excitation, whereby water droplets adhering to the surface of the mirror plate are moved and removed together with the traveling wave, and at the same time, heat generated by the load resistor A water droplet removing device for an outside mirror for an automobile, wherein the surface of the mirror plate is prevented from fogging. 2. The automotive vehicle according to claim 1, wherein an excitation piezoelectric element is arranged at one end of the rear surface of the mirror plate, and a vibration receiving piezoelectric element is arranged at the other end. Water removal device for outside mirror. 3. An automotive outside mirror according to claim 1, wherein a piezoelectric element for excitation is arranged at a central portion of a rear surface of said mirror plate, and piezoelectric elements for vibration reception are arranged at both ends. Water drop removal device.