JP2506074Y2 - Ultrasonic transducer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Purpose of Invention] (Field of Industrial Application) The present invention relates to an ultrasonic transducer having a pair of planar electrodes on both front and back surfaces.

(Prior Art) For example, in a mirror for an automobile, in recent years, an ultrasonic transducer 1 composed of a flat plate-shaped piezoelectric element as shown in FIGS. 5 and 6 is adhered to the back surface of the mirror via an adhesive, It is considered that the vibration of the ultrasonic transducer 1 is transmitted to the mirror to atomize and remove water droplets attached to the surface of the mirror.

Specifically, the ultrasonic transducer 1 has a front surface 1a and a back surface 1b.
Has a pair of first and second electrodes 2 and 3 having a planar shape, and a terminal connection portion of the second electrode 3 on the back surface 1b side on the front surface 1a side.
With the configuration having 3a, the terminals 4 and 5 are soldered to the first and second electrodes 2 and 3 on the front surface 1a side, and the back surface 1b is bonded to the back surface of the mirror. Then, when an AC voltage is applied between the terminals 4 and 5 (that is, between the first and second electrodes 2 and 3), the ultrasonic vibrator 1 vibrates and the vibration is transmitted to the mirror, and the vibration The water droplets adhering to the surface of the mirror are atomized and removed.

(Problems to be solved by the invention) By the way, in the ultrasonic vibrator 1, a crack 6 as shown by a chain double-dashed line in FIG. 6 occurs in the first electrode 2 on the surface 1a side due to abnormal vibration or the like. Then, the first electrode 2
Is divided by the crack 6 and the divided electrodes 2a, 2
Conduction failure may occur between b, which may lower the vibration efficiency of the ultrasonic vibrator 1.

The present invention has been made in view of the above circumstances, and an object thereof is to ensure conductivity even when a crack occurs in an electrode, prevent a decrease in vibration efficiency, and prevent a crack in the whole. It is to provide an ultrasonic transducer that can be used.

[Structure of the Invention] (Means for Solving the Problem) The present invention has a pair of planar electrodes on both front and back surfaces, and a terminal connection portion for the back surface electrode on the front surface side.
An ultrasonic transducer in which a back surface is supported by a mounting member is characterized in that a protective plate having conductivity is adhered to at least the electrode on the front surface side through a conductive adhesive so as to cover the electrode. .

(Function) Since a protective plate having conductivity is adhered to the electrode on the front surface side so as to cover the electrode, even if a crack occurs in the electrode and the electrode is divided, the separated electrode The electrical continuity is ensured through the protective plate between them. Further, since the protective plate can increase the strength against cracking, the entire plate is less likely to crack.

(Embodiment) An embodiment of the present invention will be described below with reference to FIGS. 1 to 4.

First, in FIG. 4, reference numeral 11 denotes a glass mirror for automobiles, for example, and a glass vibration transmission plate 12 formed in substantially the same shape as the mirror 11 is adhered and fixed to the back surface with an adhesive 13. . Then, a disc-shaped ultrasonic transducer 14 made of a piezoelectric element such as lead zirconate titanate (PZT) is bonded and fixed to the back surface of the vibration transmitting plate 12 serving as a mounting member with an adhesive 15.

As shown in detail in FIGS. 1 and 2, the ultrasonic transducer 14 has a planar shape formed on the front surface 16a and the rear surface 16b of a disk-shaped main body 16 by baking printing of silver paste, for example. While having a pair of first and second electrodes 17 and 18,
The terminal connecting portion 18a of the second electrode 18 on the front surface 16a side on the back surface 16b side
Of the vibration transmission plate 1
The back surface of 2 is adhered and supported by an adhesive 15. 19
Is a conductive protective plate made of, for example, a copper foil, and is formed in a shape that substantially matches the first electrode 17 as shown in FIG. 3 and has a hole 20 formed in the center. ,
It is adhered to the first electrode 17 via a conductive adhesive 21 so as to cover it. Reference numeral 22 is a terminal soldered to the first electrode 17 through the hole 20, and 23 is a terminal connecting portion 18a of the second electrode 18.
It is a terminal soldered to.

In the mirror having the above structure, when removing water droplets attached to the surface of the mirror 11, the ultrasonic vibrator is applied by applying an alternating voltage of, for example, 30 to 60 KHz between the pair of terminals 22 and 23 of the ultrasonic vibrator 14. Vibrate 14 laterally (plane direction). Then
The vibration is transmitted to the mirror 11 via the vibration transmission plate 12 from the adhesive portion (adhesive 13) on the outer periphery thereof. This allows
The entire surface of the mirror 11 is vibrated from the outer peripheral side, and the vibration atomizes and removes water droplets on the surface.

On the other hand, in the ultrasonic transducer 14 described above, the surface 16a
Since the protective plate 19 is adhered to the first electrode 17 on the side so as to cover the first electrode 17, it is assumed that the first electrode 17 is broken due to abnormal vibration or the like and the first electrode 17 is divided. Also, electrical continuity is secured between the separated electrodes via the protective plate 19. Therefore, the protective plate 19 can prevent the conduction failure from occurring in the first electrode 17, so that the deterioration of the vibration efficiency due to the conduction failure can be prevented. Also, by the protective plate 19,
Since the ultrasonic vibrator 14 has high strength against cracking,
The whole becomes hard to break.

The present invention is not limited to the embodiment described above and shown in the drawings. For example, the ultrasonic transducer 14 is a mirror.
It may be attached directly to the mirror 11, or may be implemented by appropriately changing it within a range not deviating from the gist such as being applicable to other than a mirror for an automobile.

[Effects of the Invention] As is apparent from the above description, according to the present invention, even if the electrode is cracked by adhering the conductive protection plate to the electrode so as to cover it. It is possible to provide an ultrasonic vibrator capable of ensuring conductivity and preventing a decrease in vibration efficiency, and further preventing the entire crack.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention, FIG. 1 is a sectional view of the ultrasonic transducer taken along the line II in FIG. 2, and FIG. 2 is a plan view of the ultrasonic transducer. 3, FIG. 3 is a plan view of the protective plate, and FIG. 4 is a cross-sectional view of a state where the ultrasonic transducer is attached to the mirror. 5 and 6 show a conventional ultrasonic transducer, FIG. 5 is a view corresponding to FIG. 1, and FIG. 6 is a view corresponding to FIG. In the drawing, 11 is a mirror, 12 is a vibration transmission plate (mounting member), 14
Is an ultrasonic transducer, 16 is a main body, 16a is a front surface, 16b is a back surface, 17
Reference numerals 18 and 18 are first and second electrodes, 18a is a terminal connecting portion, 21 is a conductive adhesive, and 22 and 23 are terminals.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (56) References Japanese Patent Laid-Open No. 55-145046 (JP, A) Actual Development 63-89362 (JP, U)

Claims (1)

(57) [Scope of utility model registration request] 1. A pair of surface-shaped electrodes are provided on both front and back surfaces, and a terminal connection portion of an electrode on the back surface is provided on the front surface side.
An ultrasonic transducer in which a back surface is supported by a mounting member is characterized in that a conductive protective plate is adhered to at least an electrode on the front surface side so as to cover the electrode via a conductive adhesive. Ultrasonic transducer.