JPH02212243A - Water-droplet removing device - Google Patents

Abstract

PURPOSE:To oscillate a plate member effectively and remove water droplets attached to the plate member effectively by laying a spacer having a non-contact portion with the plate member between the plate member and an oscillator to oscillate the spacer. CONSTITUTION:A plane-shaped spacer 30 is closely attached to part of a mirror body 11 in a side mirror, etc., for a car. Then, in the center portion of the spacer 30, a gap 31 is formed with which the mirror body 11 has no contact. Also, with the center portion of the spacer 30, a piezoelectric oscillator 20 is put in contact. In addition, the piezoelectric oscillator 20 is so formed that both electrodes 22, 23 using a flexible printed board are conductively attached to both end faces of an electrically distorting element 21 in a plate shape. On the other hand an oscillating circuit, not illustrated, is electrically connected in between both electrodes 22, 23. As a result, exchange power is applied to the piezoelectric oscillator 20 to oscillate the spacer 30 and the mirror body 11, therefore removing water droplets attached to the mirror body 11.

Description

[Detailed Description of the Invention] [Objective of the Invention] (Industrial Application Field) The present invention relates to a device for removing water droplets attached to a plate-like member such as a reflective mirror of a vehicle. This invention relates to an improved device that can cleanly remove fogging, etc.

(Prior Art) A conventional device of this type is disclosed in Japanese Patent Application Laid-Open No. 59-8548 (see FIG. 14). This device has a plate member 1 (mirror) of a vehicle reflector and a vibrator 2.
is fixed, and the vibrator 2 is vibrated by the oscillation circuit 3.

When the plate-like member 1 vibrates, if water droplets adhere to the reflective surface of the plate-like member 1, the water droplets are excited by the vibration of the plate-like member 1 and become atomized.

As shown in FIG. 14, in the conventional device,
The vibrator 2 is tightly attached to almost the entire surface of the plate-like member l.

(Problems to be Solved by the Invention) However, if the vibrator is tightly attached to the plate-shaped member, the plate-shaped member becomes difficult to bend, and the amplitude of vibration generated in the plate-shaped member becomes small. For this reason, the conventional device has a problem in that water droplets attached to the plate member are difficult to atomize.

The present invention was made in order to solve the problems of such conventional devices, and it is a common technical technique to generate large amplitude vibrations in the entire plate-shaped member by making the plate-shaped member easy to bend. Take it as a challenge.

[Structure of the invention]

(Means for solving the problem) The technical means taken to achieve the above-mentioned technical problem is to interpose a spacer between the plate-like member and the vibrator, and place the plate-like member in the center of the spacer. A part where the vibrator does not come into contact with the spacer, that is, a non-contact part, is provided, and the spacer is vibrated by the vibrator.

(Function) According to the technical means described above, the longitudinal expansion and contraction of the vibrator is transmitted to the spacer. At this time, the spacer is repeatedly bent and vibrations are excited on the spacer. The vibrations excited on the spacer propagate to the plate member to which the spacer is attached, causing the plate member to vibrate.

According to the above-described technical means, a spacer is provided between the plate-like member and the vibrator, and a non-contact portion is further formed between the spacer and the plate-like member. Therefore, the plate-like member is much easier to bend than when the vibrator is tightly attached to the plate-like member. Therefore, the vibration propagated from the spacer to the plate member is not weakened by the vibrator, and causes the entire plate member to vibrate with a large amplitude.

Water droplets attached to the plate-like member are given high kinetic energy by vibrations propagated throughout the plate-like member, drip or atomize, and are quickly removed.

In this way, according to the above-mentioned technical means, it is possible to generate large amplitude vibrations in the entire plate-like member, and the intended purpose is achieved.

(Example) Hereinafter, a first example of the present invention will be described based on the accompanying drawings.

FIG. 1 is a plan view of a vehicle side mirror using the water droplet removing device of the first embodiment. Also, Fig. 2 shows A- in Fig. 1.
It is an A sectional view.

A flat plate-shaped spacer 30 is tightly adhered to a part of the mirror 11. The spacer 30 of the device of this embodiment is formed by cutting a glass epoxy material.

As shown in FIG. 2, a gap 31 is formed approximately at the center of the spacer 30. As shown in FIG. This gap 31 is
This occurs because the mirror 11 is curved with a predetermined curvature. This gap 31 becomes a non-contact portion that does not contact the mirror 11.

The piezoelectric vibrator 20 is fixed approximately at the center of the spacer 30 with an adhesive. The piezoelectric vibrator 20 has electrodes 22 and 23 made of flexible printed M plates conductively bonded to both end surfaces of a flat electrostrictive element 21. In this embodiment, piezoelectric ceramic is used as the electrostrictive element 21. An oscillation circuit AC is electrically connected between the electrode 22 and the electrode 23.

When electric power is applied between the electrodes 22 and 23, the piezoelectric vibrator 20 expands or contracts in the thickness direction (vertical direction in the second figure) and length direction (horizontal direction in the second figure).

This will be explained with reference to FIG. 3a. (+) of the power supply to the electrode 22
When the (-) terminal of the power source is connected to the electrode 23, the piezoelectric vibrator 20 contracts in the length direction due to a transverse effect. At this time, a strong contraction force acts on one surface of the spacer 30, causing the spacer 30 to bend.

This will be explained with reference to FIG. 3b. Contrary to the case of FIG. 3a, the (-) terminal of the power source is connected to the electrode 22, and the (-) terminal of the power source is connected to the electrode 23.
When the +) terminal is connected, the piezoelectric vibrator 20 expands in the length direction due to a transverse effect. At this time, a strong stretching force acts on one surface of the spacer 30, causing the spacer 30 to bend in the opposite direction to that shown in FIG. 3a.

This will be explained with reference to FIG. 3C. When an oscillation circuit AC is connected to the piezoelectric vibrator 20 and AC power is applied to the piezoelectric vibrator 20, the spacer 30 is repeatedly bent in the opposite direction, causing the spacer 30 to vibrate. Since the spacer 30 is bonded to the mirror 11, vibrations generated in the spacer 30 are absorbed by the mirror 11.
1 and causes the mirror 11 to vibrate.

If the frequency of AC power is selected to an appropriate value, mirror 1
1 resonates, and a standing wave that is uniform and large in amplitude is generated throughout the mirror 11. This standing wave causes the mirror 11 to move at high speed. At this time, the water droplets adhering to the mirror 11 are given high kinetic energy by the mirror 11 and are removed from the mirror 11 by being dropped or atomized by gravity.

According to the device of the first embodiment, a gap 31 that does not contact the mirror 11 is formed in the center of the spacer 30 . Compared to the case where the piezoelectric vibrator 20 is directly bonded to the mirror 11, in the device of the first embodiment, the mirror 11 is easily bent because the gap 31 is formed. Therefore, the vibration excited on the mirror 11 is not weakened by the piezoelectric vibrator 20 and propagates throughout the mirror 11 with a large amplitude.

Next, a second embodiment of the apparatus will be described with reference to FIGS. 4 and 5. FIG. 4 is a plan view of the device of the second embodiment.

Moreover, FIG. 5 is a BB sectional view of FIG. 4.

The device of the second embodiment is completely the same as the device of the first embodiment except that the piezoelectric vibrator 40 and the spacer 50 are different. Therefore, in the following explanation, only the differences from the device of the first embodiment will be explained in detail, and redundant explanation will be omitted.

The spacer 50 includes two protrusions 50a and 50b. The two protrusions 50a and 50b are formed parallel to each other, and the tops of the protrusions 50a and 50b are tightly bonded to the mirror 11. A gap 51 is formed between the two protrusions 50a and 50b. This gap 51 becomes a non-contact portion that does not come into contact with the mirror 11.

A piezoelectric vibrator 40 is attached to one surface of the spacer 50. The piezoelectric vibrator 40 has an electrode 42 made of a flexible substrate conductively bonded to one surface of an electrostrictive element 41, and an electrode 43 made of a phosphor bronze plate conductively bonded to the other surface.

The electrode 43 is also adhered to one surface of the spacer 50.

A lead wire 44 is soldered to the electrode 43. Therefore, when the oscillation circuit AC is connected between the lead wire 44 and the electrode 42, the piezoelectric vibrator 40 vibrates.

According to the device of the second embodiment, a gap 51 that does not contact the mirror 11 is formed in the center of the spacer 50 . Compared to the case where the piezoelectric vibrator 40 is directly bonded to the mirror 11, in the second embodiment, the mirror 11 is easily bent because the gap 51 is formed. Therefore, the vibration excited on the mirror 11 is not weakened by the piezoelectric vibrator 40 and propagates throughout the mirror 11 with a large amplitude.

Next, a third embodiment of the apparatus will be described with reference to FIGS. 6 and 7. FIG. 6 is a plan view of the apparatus of the third embodiment.

Moreover, FIG. 7 is a sectional view taken along the line CC in FIG. 6. The device of the third embodiment is completely similar to the device of the first embodiment except for the spacer 60. Therefore, in the following explanation, only the differences from the device of the first embodiment will be explained in detail, and redundant explanation will be omitted.

The spacer 60 has four protrusions 60a, 60b, 60c, 6
It is equipped with 0d. Four protrusions 60a and 60b are formed at the corners of the spacer 60, and the protrusions 60a, 60b,
The tops of 60c and 60d are tightly glued to the mirror 11. Four protrusions 60a, 60b, 60c, 60d
A gap 61 is formed between them. This gap 61 becomes a non-contact portion that does not come into contact with the mirror 11.

A piezoelectric vibrator 20 is attached to one surface of the spacer 60.

According to the device of the third embodiment, a gap 61 that does not contact the mirror 11 is formed in the center of the spacer 60. Compared to the case where the piezoelectric vibrator 20 is directly bonded to the mirror 11, in the device of the third embodiment, since the gap 61 is formed, the mirror 11 is easily bent. Therefore, the vibration excited on the mirror 11 is not weakened by the piezoelectric vibrator 20 and propagates throughout the mirror 11 with a large amplitude.

Next, a fourth embodiment of the apparatus will be described with reference to FIGS. 8 and 9. FIG. 8 is a plan view of the device of the fourth embodiment.

Moreover, FIG. 9 is a sectional view taken along the line DD in FIG. 8. The device of the fourth embodiment is completely similar to the device of the first embodiment except that the spacer 70 is different. Therefore, in the following explanation, only the differences from the device of the first embodiment will be explained in detail, and redundant explanation will be omitted.

The spacer 70 is provided with a protrusion 70a along the outer periphery. The top of the protrusion 70a is tightly adhered to the mirror 11. A gap 71 is formed inside the protrusion 70a. This gap 71 becomes a non-contact portion that does not contact the mirror 11.

A piezoelectric vibrator 20 is attached to one surface of the spacer 70.

According to the device of the fourth embodiment, a gap 71 that does not contact the mirror 11 is formed in the center of the spacer 70 . Compared to the case where the piezoelectric vibrator 20 is directly bonded to the mirror 11, in the device of the fourth embodiment, since the gap 71 is formed, the mirror 11 is easily bent. Therefore, the vibration excited on the mirror 11 is not weakened by the piezoelectric vibrator 20 and propagates throughout the mirror 11 with a large amplitude.

In the devices of the first to fourth embodiments described above, each type of piezoelectric vibrator 20.40 was used, but the present invention is not limited to the winter type piezoelectric vibrator 20.40. . For example, a circular piezoelectric vibrator 80 as shown in FIGS. 10 and 11 can also be used.

Similarly, although the devices of the first to fourth embodiments used spacers of various types 30, 50, 60, 70, circular spacers 90, 100, etc. can also be used.

FIG. 10 is a bottom view of a spacer 90 of a device according to a fifth embodiment of the present invention, viewed from the mirror 11 side. The spacer 90 has a circular shape. Furthermore, an annular projection 90a is formed along the outer periphery of the spacer 90. The top of the protrusion 90a is tightly adhered to the mirror 11. A space 91 surrounded by the protrusion 90a becomes a non-contact portion.

FIG. 11 is a bottom view of the spacer 100 of the device according to the sixth embodiment of the present invention, viewed from the mirror 11 side. The spacer 100 has a circular shape. Additionally, three fan-shaped protrusions 100a are provided along the outer periphery of the spacer 100.

100b and 100c are formed. three protrusions 10
The tops of 0a, 100b, 1ooc are tightly glued to mirror 11. Three protrusions 100a, 1oob, 10
A space 101 surrounded by 0c becomes a non-contact portion.

Regarding the first embodiment device shown in FIGS. 1 and 2, FE
Perform computer simulation based on M analysis,
The amplitude of vibrations generated on mirror II was analyzed. The results will be explained with reference to FIGS. 12a, 12b, 13a, and 13b.

As shown in FIGS. 12a and 12b, if the spacer 30 is used, when the piezoelectric vibrator 20 is vibrated in the longitudinal direction, large amplitude vibrations can be generated in the entire mirror 11. Recognize.

In order to clearly show the effect of the spacer 30, the piezoelectric vibrator 20
We analyzed the case where the mirror was attached tightly to the mirror 11.

The analysis results are shown in FIGS. 13a and 13b. As shown in the figure, when the piezoelectric vibrator 20 is tightly attached to the mirror 11, the piezoelectric vibrator 20 on the mirror ll
The vibration of the part where 0 is pasted is weakened and the amplitude is reduced. Therefore, even if the piezoelectric vibrator 20 is vibrated, water droplets attached to the main portion of the mirror 11 to which the piezoelectric vibrator 20 is attached remain without being removed.

〔Effect of the invention〕

According to the present invention, since the mirror is more easily bent than when the vibrator is directly fixed to the mirror, the amplitude of vibration generated in the plate-like member is increased.

Therefore, water droplets attached to the plate member can be quickly removed.

Furthermore, since the non-contact portion is provided at the center of the spacer, vibrations having a large amplitude are also excited on the plate member in the portion corresponding to the vibrator. Therefore, according to the present invention, water droplets can be removed almost uniformly from all parts of the plate-like member.

[Brief explanation of the drawing]

FIG. 1 is a plan view of a vehicle side mirror depicting a first embodiment of the present invention. FIG. 2 is a sectional view taken along the line AA in FIG. 1. FIGS. 3a, 3b, and 3c are explanatory diagrams showing the operation of an embodiment of the present invention. FIG. 4 is a plan view of a vehicle side mirror depicting a second embodiment of the present invention. FIG. 5 is a sectional view taken along line BB in FIG. 4. FIG. 6 is a plan view of a vehicle side mirror depicting a third embodiment of the present invention. FIG. 7 is a sectional view taken along the line CC in FIG. 6. FIG. 8 is a plan view of a vehicle side mirror depicting a fourth embodiment of the present invention. FIG. 9 is a sectional view taken along line DD in FIG. 6. FIG. 1O is a bottom view of a spacer depicting a fifth embodiment of the present invention. FIG. 11 is a bottom view of a spacer depicting a sixth embodiment of the present invention. 12a and 12b are perspective views depicting the vibration state of the embodiment device shown in FIG. 1. FIG. FIGS. 13a and 13b are perspective views depicting the vibration state of the conventional device. FIG. 14 is a sectional view depicting a conventional device. 11...Mirror (plate-like member), 20.40...Piezoelectric vibrator (vibrator), 21.41.
...Electrostrictive element, 22.23, 42.43... Electrode, 30.50, 60, 70, 90, 100... Spacer, 31.51, 61.71... Gap (non-contact part) , 9
1.101... Space (non-contact part), AC... Oscillation circuit.

Claims (1)

[Scope of Claims] A plate-like member supported so as to be able to freely vibrate; a spacer attached to a part of the plate-like member and having a non-contact portion in the center that does not contact the plate-like member; and the spacer. A water droplet removing device comprising: a vibrator that is attached on top and expands and contracts in the length direction; and an oscillation circuit that is electrically connected to the vibrator and repeatedly bends the spacer with the vibrator.