JPH07336181A - Piezoelectric oscillation component - Google Patents

Abstract

PURPOSE:To effectively prevent the deterioration of electric characteristics by supporting the terminal part of a piezoelectric element in a state capable of oscillation. CONSTITUTION:This piezoelectric oscillation component is provided with a piezoelectric oscillator 4 consisting of the piezoelectric element 2 forming oscillation electrodes 1 on its main surfaces placed opposite to each other and a pair of holding frames 3 supporting this piezoelectric element 2 from the sides of the main surfaces along the direction of its thickness, and a pair of cases 5 holding only the periphery parts of this piezoelectric oscillation part 4 along the direction of its thickness. On the respective internal surfaces of the holding frames 3 holding the piezoelectric element 2, a pair of projections 6 supporting prescribed parts positioned inner than the terminal faces 2a of the piezoelectric element 2 are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a piezoelectric vibrating component used by being incorporated in an IC card or the like.

[0002]

2. Description of the Related Art Conventionally, as a piezoelectric vibrating component of this type, as shown in FIG. 4, a rectangular rod-shaped piezoelectric element 2 in which vibrating electrodes 1 are formed on main surfaces facing each other, so-called energy confinement. And a pair of holding frames 3 for sandwiching an end portion of the piezoelectric element 2 in the longitudinal direction from the main surface side in the thickness direction thereof, and Some piezoelectric vibrators are provided with a pair of case bodies 5 that sandwich only the peripheral edge of the piezoelectric vibrator 4 along the thickness direction. Each of the holding frames 3 has a notch 3a serving as a space for ensuring the vibration of the central portion of the piezoelectric element 2 sandwiched by the vibrating electrodes 1.
It is manufactured as having a "U" shape in a plan view in which is formed. That is, at this time, a projection 6 having a rectangular shape in plan view is formed on each of the end portions on the inner surface of each holding frame 3 so as to abut the end portion along the longitudinal direction of the piezoelectric element 2. By using an adhesive (not shown) through these protrusions 6, the piezoelectric element 2
It is joined together with.

Each of the case bodies 5 is manufactured as a rectangular shape in plan view having a size corresponding to the piezoelectric vibrating body 4, and the inner surface of each case body 5 vibrates at the central portion of the piezoelectric element 2. A recess 5a having a predetermined depth to be a space is formed. The case body 5 is also integrally joined to the piezoelectric vibrating body 4 by using an adhesive (not shown). Furthermore, each of the vibrating electrodes 1 formed on the piezoelectric element 2 extends to different end portions of the piezoelectric element 2 and then the end of the piezoelectric vibrating body 4 in which the piezoelectric element 2 and the holding frame 3 are integrated. Are connected to external lead-out electrodes 7 formed on the above-mentioned parts, and these external lead-out electrodes 7 are connected to external electrodes 8 formed on different ends of the case body 5 that holds the piezoelectric vibrating body 4 therebetween. There is. A capacitor electrode 9 is also formed between these external electrodes 8.

[0004]

By the way, in the piezoelectric vibrating component having the above-mentioned conventional structure, the end portion along the longitudinal direction of the piezoelectric element 2 is vigorously fixed and supported by the projection 6 of the holding frame 3. Since it is in a restrained state that cannot be obtained, the vibration generated in the central portion of the piezoelectric element 2, that is, the central portion of the piezoelectric element 2 sandwiched by the vibrating electrodes 1 is hindered by being affected by these end portions. I will end up. As a result, the vibration state of the piezoelectric vibrating component in which the piezoelectric element 2 is incorporated and the vibration state of the single piezoelectric element 2 are significantly different, and the electrical characteristics of the piezoelectric vibrating component when compared with the single piezoelectric element 2 are significantly deteriorated. The inconvenience was to occur.

Further, the vibrating electrode 1 formed on the main surface of the piezoelectric element 2 and the external extraction electrode 7 formed on the end portion of the piezoelectric vibrating body 4 are in only one place (indicated by symbol A in the figure). Therefore, since the connections are made only in a straight line, there is a disadvantage that the reliability of electrical connection is poor.

The present invention was devised in view of these disadvantages, and has an arrangement capable of vibratingly supporting the end portion of a piezoelectric element and effectively preventing deterioration of electrical characteristics. A piezoelectric vibrating component is provided.

[0007]

A piezoelectric vibrating component according to the present invention comprises a piezoelectric element having vibrating electrodes formed on opposing main surfaces, and a pair of the piezoelectric elements sandwiching the piezoelectric element from the main surface side along its thickness direction. In order to achieve the above object, the piezoelectric element is provided with a piezoelectric vibrating body composed of a holding frame and a pair of case bodies that sandwich only the peripheral portion of the piezoelectric vibrating body along the thickness direction thereof. A pair of protrusions for supporting a predetermined portion located inside the end surface of the piezoelectric element is provided on the inner surface of each holding frame to be sandwiched. Then, at this time, an external extraction electrode may be formed at the end portion of the piezoelectric vibrating body so as to reach the outer surface of each of the protrusions provided on each holding frame and be electrically connected to the vibrating electrode. A recess may be formed on the inner surface so as to correspond to the end of the piezoelectric element positioned outside the protrusion of each holding frame and that is wider than the thickness of the end.

[0008]

According to the above construction, since the end portion of the piezoelectric element along the longitudinal direction is not fixedly supported and is in a vibrating state, the vibration generated at the central portion of the piezoelectric element is generated from the end portion. It will not be affected and hindered.

[0009]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing the overall structure of a piezoelectric vibrating component according to this embodiment, and FIGS. 2 and 3 are external perspective views showing a modified example of the piezoelectric vibrating body. Since the configurations of the piezoelectric vibrating component and the piezoelectric vibrating body are basically the same as those of the conventional example, the same or corresponding parts and portions as those in FIG. 4 are denoted by the same reference numerals in FIGS. The detailed description of is omitted.

As shown in FIG. 1, the piezoelectric vibrating component according to the present embodiment has a rectangular rod-shaped piezoelectric element 2 in which vibrating electrodes 1 are formed on main surfaces facing each other, and the piezoelectric element 2.
A piezoelectric vibrating body 4 composed of a pair of holding frames 3 for sandwiching the piezoelectric vibrating body from the main surface side, and a pair of case bodies 5 sandwiching only the peripheral edge of the piezoelectric vibrating body 4 along the thickness direction. The holding frame 3 and the case body 5 are made of a ceramic material such as alumina. At this time, a pair of protrusions 6 that support a predetermined portion located inside the end surface 2a of the piezoelectric element 2 are provided on the inner surface of each holding frame 3, and have a predetermined height and width. Each of the protrusions 6 having a rectangular shape in plan view is integrally bonded to a predetermined portion of the piezoelectric element 2 by using an adhesive (not shown).

That is, in the conventional example, each of the projections 6 of the holding frame 3 supports the end portion of the piezoelectric element 2 along the longitudinal direction, whereas each of the projections 6 of the holding frame 3 in the present embodiment is piezoelectric. It supports a predetermined portion located inside the end surface 2a of the element 2. Therefore,
Each end of the piezoelectric element 2 in the piezoelectric vibrating body 4 configured by using these holding frames 3 is located outside a predetermined portion supported by the protrusions 6 of both holding frames 3 and therefore can vibrate. It remains in the state.

By the way, in the present embodiment, the projections 6 formed on the inner surface of each holding frame 3 are supposed to have a rectangular shape in plan view as shown in FIG. The modification shown in each of FIG. 3, that is, FIG.
Needless to say, it may have a semicircular shape in plan view as shown in FIG. 3 or a triangular shape in plan view as shown in FIG. When the protrusions 6 having these shapes in plan view are adopted, the contact area between the piezoelectric element 2 and the protrusions 6 is reduced, and as a result, the factors that hinder the vibration of the piezoelectric element 2 are reduced.

Further, an external extraction electrode 7 is formed on each end portion along the longitudinal direction of the piezoelectric vibrating body 4 in which the piezoelectric element 2 and the holding frame 3 are integrated so as to reach the outer surface of the projection 6. And the vibrating electrode 1 formed on the piezoelectric element 2
Of the piezoelectric element 2 are extended to different ends of the piezoelectric element 2 and connected to the external extraction electrodes 7. At this time, since the external extraction electrode 7 reaches the outer surface of the protrusion 6, each vibrating electrode 1 has a larger number of portions (reference numerals A and B in the figure) than in the case of the conventional example shown in FIG. (Shown by), the connection length between the vibrating electrode 1 and the external extraction electrode 7 is longer than that of the conventional example.

Further, each of the case bodies 5 is made to have a rectangular shape in plan view having a size corresponding to the piezoelectric vibrating body 4, and these case bodies 5 use an adhesive (not shown). In addition, it is integrally joined to the peripheral portion of the piezoelectric vibrating body 4. At this time, at the center position on the inner surface of each case body 5, there is formed a recess 5a having a predetermined depth to serve as a vibration space at the center of the piezoelectric element 2, and at the end position of the inner surface. That is, at the end position corresponding to the end of the piezoelectric element 2 located outside the protrusion 6 of each holding frame 3, the recess 10 having a predetermined depth that is wider than the thickness of the end of the piezoelectric element 2. Are formed. Therefore, the piezoelectric vibrating body 4 is sandwiched by the holding frame 3.
The end portion of the piezoelectric element 2 constituting the above, that is, the end portion of the piezoelectric element 2 positioned outside the predetermined portion supported by the protrusion 6 of the holding frame 3 and in a vibrating state, is formed in each case body. It will be kept in a state where it can freely vibrate without coming into contact with the inner surface of 5.

Furthermore, the external electrodes 8 are formed on the ends of the case body 5 which are different from each other, and the external extraction electrodes 7 formed on the ends of the piezoelectric vibrating body 4 are connected to the external electrodes 8 respectively. Connected with. Therefore, at this time, the vibration electrode 1 formed on the main surface of the piezoelectric element 2 is connected to the external electrode 8 on each case body 5 through the external extraction electrode 7 formed on the piezoelectric vibration body 4. It means that there is continuity above. Reference numeral 9 in the figure denotes each case body 5
Shows the capacitor electrode formed in the upper center,
Each of these capacitor electrodes 9 is provided so as to generate a capacitance with each external electrode 8.

[0017]

As described above, according to the piezoelectric vibrating component of the present invention, the end portion along the longitudinal direction of the piezoelectric element is not fixedly supported and is in a vibrating state, so that the piezoelectric element The vibration generated in the central portion of the element is not affected and blocked by the end portions. as a result,
The vibration state of the piezoelectric vibrating component incorporating the piezoelectric element is not so different from the vibrating state of the piezoelectric element alone, and it is possible to effectively prevent deterioration of the electrical characteristics of the piezoelectric vibrating component and make a great improvement. it can. Further, by adopting the configuration of the present invention, the number of connection points between the vibrating electrode and the external extraction electrode is increased and the connection length is increased, so that there is an effect that the reliability of electrical connection can be significantly improved.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing an overall configuration of a piezoelectric vibrating component according to this embodiment.

FIG. 2 is an external perspective view showing a modified example of the piezoelectric vibrating body.

FIG. 3 is an external perspective view showing another modification of the piezoelectric vibrating body.

FIG. 4 is an exploded perspective view showing an overall configuration of a piezoelectric vibration component according to a conventional example.

[Explanation of reference numerals] 1 vibrating electrode 2 piezoelectric element 3 holding frame 4 piezoelectric vibrating body 5 case body 6 protrusion 7 external extraction electrode 10 concave portion

Claims (3)

[Claims] 1. A piezoelectric element (2) having a vibrating electrode (1) formed on opposing main surfaces and a pair of holding frames (2) sandwiching the piezoelectric element (2) from the main surface side along the thickness direction thereof. A piezoelectric vibrating component comprising a piezoelectric vibrating body (4) composed of 3) and a pair of case bodies (5) sandwiching only the peripheral edge of the piezoelectric vibrating body (4) along the thickness direction thereof, A piezoelectric element characterized in that a pair of protrusions (6) for supporting a predetermined portion located inside the end surface (2a) of the piezoelectric element (2) is provided on the inner surface of each holding frame (3). Vibration parts. 2. An external extraction electrode (1) at the end of the piezoelectric vibrating body (4) reaching the outer surface of each of the protrusions (6) provided on the holding frame (3) and conducting with the vibrating electrode (1). 7) The piezoelectric vibrating component according to claim 1, wherein the piezoelectric vibrating component is formed. 3. The inner surface of each case body (5) corresponds to the end of the piezoelectric element (2) located outside the protrusion (6) of each holding frame (3), The piezoelectric vibration component according to claim 2, wherein a concave portion (10) having a width wider than that of the portion is formed.