JPH10293032A - Piezoelectric vibration gyro and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration gyro with improved working efficiency and reliability and its manufacture by connecting a lead wire, for example, by wire bonding. SOLUTION: A piezoelectric ceramic vibrator 1 where band-shaped electrodes 2, 4, 5, and 6 are formed on an outer-periphery surface is supported by the node of vibration, and a salient electrode 16 is formed at a connection part between the band-shaped electrodes 2, 4, 5, and 6 and terminals 11, 12, 13, and 14 when connecting a lead wire 15 of the vibrator 1 to the band-shaped electrodes 2, 4, 5, and 6 and the terminals 11, 12, 13, and 14 of a support tool.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a camera-integrated VT.
The present invention relates to a piezoelectric vibrating gyroscope used for a gyroscope mounted on an R camera shake preventing apparatus, a car navigation system, and the like, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A piezoelectric vibrating gyroscope is a gyroscope utilizing a mechanical phenomenon in which when a rotating angular velocity is given to a vibrating object, a Coriolis force is generated in a direction perpendicular to the direction of the vibration. In this gyroscope, in a vibration system configured to be able to excite and detect in two directions orthogonal to each other, the piezoelectric ceramic vibrator itself is connected to a line where two vibrating surfaces intersect while one vibration is excited. When rotated about a parallel axis as a central axis, a force acts in a direction perpendicular to this vibration by the action of the aforementioned Coriolis force, and the other vibration is excited. The magnitude of the vibration is proportional to the magnitude of the vibration on the input side and the rotational angular velocity. Therefore, when the input voltage is constant, the magnitude of the rotational angular velocity can be obtained from the magnitude of the output voltage.

FIG. 4 is a perspective view showing the structure of a conventional piezoelectric vibrating gyroscope. As shown in FIG. 4, strip electrodes 2, 3, 4, parallel to the length direction are provided at positions allocated at a predetermined angle on the outer peripheral surface of the cylindrical piezoelectric ceramic vibrator 1.
5, 6, and 7 are formed. After alternately connecting these strip electrodes to each other and performing polarization processing as two terminals, after the polarization processing, every other strip electrodes 3, 5, and 7 are electrically connected to form a common ground electrode, and Of the three strip electrodes, the strip electrode 2 is a drive electrode, and the strip electrodes 4 and 6 are detection electrodes. In this state, a bending vibration is caused in the vibrator 1 and the vibrator 1 is rotated around an axis parallel to the central axis thereof.
A Coriolis force acts on the vibrator 1 in a direction perpendicular to the direction of the bending vibration, and a bending vibration in this direction is newly generated. In addition, the vibrator 1 uses a support member 9 via a soft elastic layer 8 such as silicone rubber to position the node of the vibration at the time of resonance of the bending vibration.
Circuit board 1 which is supported by and has a drive detection circuit formed thereon
It is fixed to 0.

Conventionally, in a piezoelectric vibrating gyroscope of this kind, electrodes 2, 4, 6 and electrodes 3, 5, 7 of a vibrator 1 are provided.
And the connection of the terminals 11, 12, 13, 14 of the support 9
The terminals 11, 12, 13, 14 and the electrodes 2, 4, 5, 6 are connected to the leads 15 made of tin-plated soft copper wire of φ40 μm.
And soldering at a total of eight locations.

However, since the lead wire is connected to the strip electrode and the terminal by soldering, the workability is not improved, and furthermore, the reliability is low due to the attachment of the lead wire to the vibrator, disconnection, and the like. There was a problem.

[0006]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problem of soldering the electrodes of the conventional vibrator and the terminals of the support member by connecting the lead wires to the strip electrodes and the terminals by wire bonding or the like. Accordingly, it is an object of the present invention to provide a piezoelectric vibrating gyroscope with improved workability and improved reliability, and a method for manufacturing the same.

[0007]

According to the present invention, a vibration node of a piezoelectric ceramic vibrator having a band-shaped electrode formed on an outer peripheral surface is supported by a support, and a lead wire is connected to the band-shaped electrode and a terminal of the support. Wherein a protruding electrode is formed at a connecting portion between the strip-shaped electrode and the terminal connected to the lead wire.

Further, the present invention is the above-mentioned piezoelectric vibrating gyroscope, wherein the strip-shaped electrode and the protruding electrode are made of the same material.

Further, the present invention is the above-mentioned piezoelectric vibrating gyroscope, wherein the strip-shaped electrode and the protruding electrode are made of different materials.

Further, the present invention is the method for manufacturing a piezoelectric vibrating gyroscope, wherein the protruding electrodes are formed after forming the strip electrodes.

Further, the present invention is the above-mentioned method for manufacturing a piezoelectric vibrating gyroscope, wherein the strip-shaped electrode and the protruding electrode are simultaneously formed.

That is, according to the present invention, a plurality of strip-shaped electrodes formed on the outer peripheral surface of the rod-shaped piezoelectric ceramic vibrator in parallel with the longitudinal direction, and a node for supporting the vibration of the piezoelectric ceramic vibrator. The connection quality is stable by connecting the terminals attached to the support with the protruding electrodes in advance and forming the protruding electrodes on the terminals and the strip electrodes, and connecting the lead wires to each protruding electrode by a connection technique such as wire bonding. And
Reliability is improved.

Further, according to the present invention, the connection between the electrodes of the piezoelectric ceramic vibrator and the circuit board via the terminals of the support is facilitated, and a measure against disconnection of the lead wire is made possible. Stable and reliable.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS After a strip electrode is formed on a piezoelectric ceramic vibrator, a protruding electrode made of the same material or a different material as the strip electrode is formed. Also, a protruding electrode is formed on the terminal of the support. After the vibrator is supported by the support, a lead wire is connected to the strip electrode of the vibrator and the protruding electrode of the terminal of the support by wire bonding or the like. As another method, a strip electrode and a protruding electrode can be simultaneously formed.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a perspective view showing a structure of a piezoelectric vibrating gyroscope according to an embodiment of the present invention. FIG. 2 is a sectional view showing the structure of the piezoelectric vibrating gyroscope according to the embodiment of the present invention, FIG. 2 (a) is a sectional view taken along line AA of FIG. 1, and FIG. 2 (b) is a sectional view taken along line BB of FIG. FIG. FIG. 3 is a cross-sectional view schematically showing a main part of a piezoelectric ceramic vibrator used in a piezoelectric vibrating gyroscope according to an embodiment of the present invention. FIG. 3A shows a protruding electrode (bump) formed integrally with a strip electrode. FIG. 3B is a cross-sectional view showing a state in which the protruding electrodes are formed separately from the strip electrodes.

(Embodiment 1) In Embodiment 1, as shown in FIG. 3B, the projecting electrode 16 and the strip electrodes 2, 4, 5, 6
(4 and 6 are not shown) are made of the same material,
An example in which bumps 16 are formed after forming 4, 5, and 6 is shown. As shown in FIGS. 1 and 2, first, the band-shaped electrodes 2, 3, 4, 5, and 5 are screen-printed or plated on the piezoelectric ceramic vibrator 1 using a silver paste, a nickel paste, a copper paste, or the like. After forming 6 and 7, the strip-shaped electrode 2 serving as a drive electrode, the strip-shaped electrode 4 serving as a detection electrode,
A projection made of silver, nickel, or copper, which is the same material as that of the strip-shaped electrode, was formed by ball bonding or the like on the connection portion of the lead wire of the strip-shaped electrode 6 and the strip-shaped electrode 5 serving as a common ground electrode. Also, the terminal 11 of the support 9,
Similarly, the protruding electrodes 16 were formed at the connection portions of the lead wires 12, 13, and 14. Next, the vibrator 1 is supported at a position of a node of vibration at the time of resonance of bending vibration by a support 9 via a soft elastic layer 8 such as silicone rubber, and a lead made of a gold wire, an aluminum wire, a copper wire, or the like. The wires 15 were connected by wire bonding or heat fusion using a laser. Therefore, the piezoelectric vibrating gyroscope according to the present embodiment enables connection such as wire bonding, as compared with the conventional piezoelectric vibrating gyroscope, so that the quality of the connection and the workability are improved.

(Embodiment 2) In Embodiment 2, as shown in FIG. 3A, the protruding electrodes 16 and the strip electrodes 2, 4, 5, 6
(4 and 6 are not shown) are made of the same material and are integrally formed. As shown in FIGS. 1 and 2, when the band electrodes 2, 3, 4, 5, 6, 7 made of silver, nickel, copper, or the like are formed on the vibrator 1 by screen printing, plating, or the like. The connection portions with the 4, 5, and 6 lead wires were selectively thickened to form the protruding electrodes 16. Next, as in the first embodiment, the terminals 11, 12, 13, 1
The protruding electrode 16 was also formed at the connection part of the lead wire of No. 4 and the vibrator 1 was supported by the support 9, and then the lead wire 15 was connected to the protruding electrode 16. Therefore, the piezoelectric vibrating gyroscope according to the present embodiment enables connection such as wire bonding, as compared with the conventional piezoelectric vibrating gyroscope, so that the quality of the connection and the workability are improved.

(Embodiment 3) In Embodiment 3, as shown in FIG. 3B, the protruding electrode 16 and the strip electrodes 2, 4, 5, 6
(4 and 6 are not shown) are made of different materials,
An example in which bumps 16 are formed after forming 4, 5, and 6 is shown. As shown in FIGS. 1 and 2, the band-shaped electrodes 2, 3, 4, 5,
After the formation of the electrodes 6 and 7, gold projections or solder projections were formed on the connection portions of the strip-shaped electrodes with the lead wires 2, 4, 5 and 6 by ball bonding or the like to form projection electrodes 16. . Next, similarly to the first embodiment, the terminal 11 of the support 9
The protruding electrodes 16 are also provided at the connection portions of the lead wires 12, 13, and 14.
After forming and supporting the vibrator 1 with the support 9, the lead wire 15 was connected to the protruding electrode 16. Therefore, the piezoelectric vibrating gyroscope of the present embodiment is
Since connection such as wire bonding becomes possible, connection quality and workability are improved.

(Embodiment 4) In Embodiment 4, as shown in FIG. 3B, the protruding electrodes 16 and the strip electrodes 2, 4, 5, 6
(4 and 6 are not shown) are made of different materials,
An example in which bumps 16 are formed after forming 4, 5, and 6 is shown. As shown in FIGS. 1 and 2, the band-shaped electrodes 2, 3, 4, 5,
After forming the electrodes 6 and 7, a gold chip or the like, which is an electric conductor, was bonded to the connection portion of the strip-shaped electrodes 2, 4, 5, and 6 with the lead wires by brazing or the like to form the protruding electrode 16. Next, as in the first embodiment, the terminals 11, 12, 13, 1
The protruding electrode 16 was also formed at the connection part of the lead wire of No. 4 and the vibrator 1 was supported by the support 9, and then the lead wire 15 was connected to the protruding electrode 16. Therefore, the piezoelectric vibrating gyroscope according to the present embodiment enables connection such as wire bonding, as compared with the conventional piezoelectric vibrating gyroscope, so that the quality of the connection and the workability are improved.

[0020]

As described above, according to the present invention,
A piezo-electric vibrating gyroscope with improved workability, in which lead wires can be connected by wire bonding or the like, and with improved reliability, and a method for manufacturing the same can be provided. The present invention can be applied to connection of a lead wire to the outside of a piezoelectric element having electrodes.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the structure of a piezoelectric vibrating gyroscope according to an embodiment of the present invention.

FIG. 2 is a sectional view showing a structure of a piezoelectric vibrating gyroscope according to an embodiment of the present invention. FIG. 2A is a sectional view taken along line AA of FIG. FIG.
(B) is BB sectional drawing of FIG.

FIG. 3 is a sectional view schematically showing a main part of a piezoelectric ceramic vibrator used in the piezoelectric vibrating gyroscope according to the embodiment of the present invention.
FIG. 3A is a cross-sectional view showing a state in which a protruding electrode is formed integrally with a strip electrode. FIG. 3B is a cross-sectional view showing a state in which the protruding electrodes are formed separately from the strip electrodes.

FIG. 4 is a perspective view showing the structure of a conventional piezoelectric vibrating gyroscope.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 (piezoelectric ceramic) vibrator 2, 3, 4, 5, 6, 7 (strip-shaped) electrode 8 soft elastic layer 9 support 10 circuit board 11, 12, 13, 14 terminal 15 lead wire 16 protruding electrode

Claims (5)

[Claims] 1. A piezoelectric vibrating gyroscope in which a node of vibration of a piezoelectric ceramic vibrator having a band-shaped electrode formed on an outer peripheral surface is supported by a support, and a lead wire is connected to the band-shaped electrode and a terminal of the support. 3. The piezoelectric vibrating gyroscope according to claim 1, wherein a protruding electrode is formed at a connection portion between the strip-shaped electrode and the terminal connected to the lead wire. 2. The piezoelectric vibrating gyroscope according to claim 1, wherein said strip-shaped electrode and said protruding electrode are made of the same material. 3. The piezoelectric vibrating gyroscope according to claim 1, wherein said strip-shaped electrode and said protruding electrode are made of different materials. 4. The method for manufacturing a piezoelectric vibrating gyroscope according to claim 1, wherein the protruding electrode is formed after the band-shaped electrode is formed. 5. The method of manufacturing a piezoelectric vibrating gyroscope according to claim 1, wherein said strip-shaped electrode and said protruding electrode are formed simultaneously.