JPH102740A - Piezoelectric vibration gyro - Google Patents

Abstract

(57) [Summary] [PROBLEMS] To provide a piezoelectric vibrating gyroscope having stable output temperature characteristics at rest. SOLUTION: A cylindrical spacer 10 is fixed to both ends of a columnar piezoelectric ceramic vibrator 1 in the axial direction. The cylindrical spacer has a concave portion 11 that covers the outer peripheral portion without contacting the outer peripheral portion of the piezoelectric ceramic vibrator at a node or a nodal line. The cylindrical spacer is inserted into the through hole 6 of the support member 5 made of insulating soft elastic rubber and adhered by the adhesive 9.
The support 5 is fixed to a holder 7 made of resin. One end of the signal input / output lead 3 is connected to the piezoelectric ceramic vibrator at a node or a nodal line in the recess, and the other end of the signal input / output lead is soldered to a metal terminal rod 8 installed on the holder. .

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a camera-integrated VT.
The present invention relates to a so-called piezoelectric vibrating gyroscope using ultrasonic vibration of a piezoelectric vibrator, and more particularly to a method and structure for supporting a piezoelectric ceramic vibrator, among gyroscopes used for preventing hand shake of R and for a navigation system of an automobile.

[0002]

2. Description of the Related Art A piezoelectric vibrating gyroscope is a gyroscope utilizing a mechanical phenomenon that when a rotating angular velocity is given to a vibrating object, a Coriolis force is generated in a direction perpendicular to the vibration direction. In a vibration system configured so that excitation and detection in two directions orthogonal to each other are possible, in a state where one vibration is excited, the vibrator itself is centered on the axis parallel to the line where the two vibration planes intersect When rotated, 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 view showing a schematic structure of a cylindrical piezoelectric ceramic vibrator 1 which is a main body of the piezoelectric vibrating gyroscope, and a position of 22.4% from both ends with respect to a longitudinal direction of the cylindrical piezoelectric ceramic vibrator 1. A signal input / output lead wire 3 is fixed by solder on a line (hereinafter abbreviated as a node line 4) connecting the nodes of the bending vibration in the width direction and at the center in the width direction of each strip electrode 2. Is subjected to a polarization treatment.

FIG. 5 is a perspective view of a support (conventional) 5 made of a soft elastic material used to support the piezoelectric ceramic vibrator on a node line 4 thereof.

FIGS. 6A and 6B are perspective views of a holder portion of the conventional piezoelectric ceramic vibrator 1, wherein FIG. 6A is a view before the vibrator is mounted, and FIG. 6B is a view after the vibrator is mounted. The support tool 5
An annular body made of an insulating rubber-like elastic material having a through hole 6 in the center having the same diameter as the outer diameter of the piezoelectric ceramic vibrator 1, and a through hole of a holder 7 having the same diameter as the outer diameter of the annular support 5. It fits into the hole and is glued. This holder 7
The piezoelectric ceramic vibrator 1 is inserted into the through hole 6 of the support 5 which is fitted and adhered, and the nodal line 4 of the bending vibration of the piezoelectric ceramic vibrator 1 is formed at the edge of the through hole 6 of the support 5. An adhesive 9 containing silicone rubber as a main component is injected and bonded to a portion where the annular support 5 and the piezoelectric ceramic vibrator 1 are in contact with each other. Next, the signal input / output lead wire 3 connected to the drive or detection strip electrode 2 is soldered to the metal terminal rod 8.

[0005]

In the conventional vibrator for a piezoelectric vibrating gyroscope shown in FIG. 6, the piezoelectric ceramic vibrator 1 is inserted into a through hole 6 of a support 5 which is fitted into a holder 7 and adhered. The piezoelectric ceramic vibrator 1
An adhesive 9 containing silicone rubber as a main component is injected and adhered to a portion in contact with the annular support 5. The adhesive 9 containing silicone rubber as a main component is one that solidifies at a high temperature. When the temperature is increased from room temperature to high temperature, the adhesive 9 containing the silicone rubber as a main component is used.
Is temporarily reduced in viscosity as compared with that at normal temperature, and is further solidified when left at a high temperature. At the time of bonding with the adhesive 9 containing silicone rubber as a main component, since the viscosity is high at normal temperature, it does not enter into the bonding surface and a small gap near the bonding surface, but the viscosity once decreases in a high temperature state. As a result, it flows into every corner of the bonding surface due to the capillary phenomenon, and the bonding strength is improved. However, the piezoelectric ceramic vibrator 1
A signal input / output lead wire 3 is electrically connected to the driving or detecting band electrode 2 near the bonding portion between the support member 5 and the support member 5 made of a soft elastic body. When the agent 9 adheres to the joint between the signal input / output lead wire 3 and the piezoelectric ceramic vibrator 1, vibration leakage occurs through the signal input / output lead wire 3. The signal input / output lead wire 3 is electrically connected to the driving or detecting strip electrode 2 on the node line 4 of the piezoelectric ceramic vibrator 1 and the adhesive 9 containing silicone rubber as a main component. In order to avoid as much as possible from adhering to the joint between the signal input / output lead wire 3 and the piezoelectric ceramic vibrator 1, the bonding part between the soft elastic support 5 and the piezoelectric ceramic vibrator 1 is It is necessary to shift the piezoelectric ceramic vibrator 1 slightly above the nodal line 4,
As a result, the mechanical quality factor Qm of the piezoelectric ceramic vibrator 1 is reduced, and the sensitivity is reduced. Node line 4
The vibration is leaked through the support member 5 because it is supported by being shifted from above. Conversely, disturbances via the support 5 affect the bending vibration of the piezoelectric ceramic vibrator 1, and the characteristics of the piezoelectric vibrating gyroscope, particularly the output at rest, deteriorate.

SUMMARY OF THE INVENTION An object of the present invention is to provide a piezoelectric vibrating gyroscope which eliminates the above-mentioned drawbacks caused by the assembly process and structure of the conventional piezoelectric vibrating gyroscope, and in particular, has a stable output temperature characteristic at rest.

[0007]

According to the present invention, a cylindrical piezoelectric ceramic vibrator 1 vibrating at one wavelength resonance is provided.
In a piezoelectric vibrating gyroscope that is bonded and fixed to a holder 7 via a support member 5 made of a soft elastic body, the piezoelectric vibrating gyroscope is fixed to both ends in the axial direction of the piezoelectric ceramic vibrator, and at a node or a nodal line, the outer periphery of the piezoelectric ceramic vibrator A cylindrical spacer having a concave portion 11 that is in non-contact with and covers the portion is provided, and the cylindrical spacer and the support member 5 made of a soft elastic material and a silicone at a node or a line of the piezoelectric ceramic vibrator. It is supported by an adhesive 9 containing rubber as a main component, and a nodal line 4 on the surface of the piezoelectric ceramic vibrator.
A piezoelectric vibrating gyroscope is obtained in which the signal input / output lead wire 3 taken out from above is not fixed to a portion other than the node line of the piezoelectric ceramic vibrator by the adhesive 9 containing silicone rubber as a main component.

Further, according to the present invention, in order to prevent the adhesive 9 containing silicone rubber as a main component from adhering to the signal input / output lead wire, the supporting portion of the piezoelectric ceramic vibrator is connected to the piezoelectric ceramic vibrator. A piezoelectric vibrating gyroscope that does not need to be displaced from the child node or node line is obtained.

[0009]

In the piezoelectric vibrating gyroscope according to the present invention, the piezoelectric ceramic vibrator 1 and the nodal line 4 of the piezoelectric ceramic vibrator 1 are provided.
Since the signal input / output lead wire 3 taken out from above is not fixed except on the nodal line with the adhesive 9 containing silicone rubber as a main component, there is no vibration leaking from the signal input / output lead wire 3 and Since the piezoelectric ceramic vibrator 1 is supported by the support member 5 made of a soft elastic body without being displaced from the nodal line 4, the support member 5 made of the soft elastic body
Vibration does not leak to the outside via. In other words, in the present invention, since no disturbance is applied to portions other than the node line of the piezoelectric ceramic vibrator 1, even when the disturbance changes, a piezoelectric vibrating gyroscope having particularly stable output temperature characteristics at rest can be obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 shows a state in which a support member 5 and a piezoelectric ceramics vibrator 1 to which a cylindrical spacer 10 is attached are incorporated into a holder 7 of a columnar piezoelectric vibrator 1. FIG. 1 shows an axial cross section of the piezoelectric ceramic vibrator 1 in order to facilitate understanding of a support state of the piezoelectric ceramic vibrator 1.

The assembling procedure will be described. First, a soft elastic rubber support having insulating properties is provided in a through hole near both ends of a resin holder 7 so as to be perpendicular to the axial direction of the piezoelectric ceramic vibrator 1. 5 is fitted and adhered. Supporting device 5
Is an annular body having a triangular cross section.

Next, cylindrical spacers 10 fixed to both ends of the piezoelectric ceramic vibrator 1 in the axial direction are inserted into the through holes 6 of the support 5. In the cylindrical spacer 10,
A concave portion 11 is provided which is not in contact with the outer peripheral portion of the piezoelectric ceramic vibrator 1 and covers the same. This recess 1
In FIG. 1, a signal input / output lead wire 3 is soldered to a node line on the surface of the piezoelectric ceramic vibrator 1.

Subsequently, an adhesive 9 containing silicone rubber as a main component is injected near a portion where the cylindrical spacer 10 and the edge of the through hole 6 of the support 5 are in contact with each other. The spacer 10 is temporarily bonded to the holder 7. The adhesive used here is a thermosetting silicone adhesive.

Further, the holder 7 is left in a high temperature atmosphere. The adhesive 9 containing silicone rubber as a main component, which was in a jelly state at normal temperature, liquefies due to a decrease in viscosity, spreads over details, and solidifies when left at a high temperature.

The metal terminal rod 8 is placed on the holder 7 and the signal input / output lead 3 is soldered to the metal terminal rod 8.

FIG. 2 shows a static output temperature characteristic of the piezoelectric vibrating gyroscope according to one embodiment of the present invention.

FIG. 3 shows a static output temperature characteristic of a conventional piezoelectric vibrating gyroscope.

A comparison between FIG. 2 and FIG. 3 shows that even when the temperature rises and falls, the stationary output of the present invention does not increase or decrease more than the conventional output.

[0020]

As described above, according to the present invention, there is provided a piezoelectric vibrating gyroscope for detecting a rotational angular velocity using a bending vibration mode of a cylindrical piezoelectric ceramic vibrator vibrating at one wavelength resonance. There is no leakage of vibration from the support part of the ceramic vibrator and the signal input / output lead wire, and it is possible to provide a piezoelectric vibrating gyroscope which has excellent output temperature characteristics especially at rest and has stable characteristics against changes in disturbance. .

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part of an embodiment of the present invention.

FIG. 2 shows a static output temperature characteristic of an embodiment of the present invention.

FIG. 3 shows a static output temperature characteristic of a conventional piezoelectric vibrating gyroscope.

FIG. 4 is a perspective view schematically showing a columnar piezoelectric ceramic vibrator.

FIG. 5 is a perspective view of a conventional support.

6A and 6B are perspective views of a conventional piezoelectric vibrating gyroscope before and after assembly, wherein FIG. 6A shows a state before assembly and FIG. 6B shows a state after assembly.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 piezoelectric ceramic vibrator 2 strip electrode 3 signal input / output lead wire 4 node line 5 support 6 through hole 7 holder 8 metal terminal rod 9 adhesive 10 cylindrical spacer 11 recess

Claims (1)

[Claims] 1. A piezoelectric vibrating gyroscope for detecting a rotational angular velocity using a bending vibration mode of a cylindrical piezoelectric ceramic vibrator vibrating at one wavelength resonance, wherein the piezoelectric vibrating gyroscope is fixed to both ends in the axial direction of the piezoelectric ceramic vibrator. And, at a node or a node line, a cylindrical spacer having a concave portion covering the outer peripheral portion in a non-contact manner with the outer peripheral portion of the piezoelectric ceramic vibrator is attached to a holder via a support made of an insulating elastic material, A piezoelectric vibrating gyroscope, wherein a signal input / output lead wire is connected to the piezoelectric ceramic vibrator at a node or a nodal line in the concave portion.