JP2001241952A - Angular velocity sensor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an angular velocity sensor which is thin and which is of high sensitivity without forming an electrode of a high-accuracy comb-teeth structure for drive and for detection. SOLUTION: The angular velocity sensor is provided with a first tuning fork piece 2a and a second tuning fork piece 2b. The sensor is provided with a first bend vibrating piece 6 which is situated between them. The sensor is provided with a third tuning fork piece 3a and a fourth tuning fork piece 3b which face them. The sensor is provided with a second bend vibrating piece 7. The sensor is provided with additional mass parts 4a, 4b, 5a, 5b, 8, 9 which are installed at tip parts of the respective tuning fork pieces and the bend vibrating pieces 2a, 2b, 3a, 3b, 6, 7. The sensor is provided with a driving electrode 12a and a driving electrode 13a which are installed at the second and fourth tuning fork pieces 2b, 3b. The sensor is provided with a monitor electrode 14a and a monitor electrode 15a which are installed at the first and third tuning fork pieces 2a, 3a. The sensor is provided with a detecting electrode 16a and a detecting electrode 17a which are installed at the first and second bend vibrating pieces 6, 7.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an angular velocity sensor used for, for example, an attitude control of a car, navigation, prevention of camera shake, remote control for remote control, and the like.

[0002]

2. Description of the Related Art As a conventional thin angular velocity sensor, one described in Japanese Patent Application Laid-Open No. H10-170276 is known. This angular velocity sensor has a structure in which an additional mass portion at the center is supported in a plane by a thin beam. In addition, a driving unit for driving the additional mass unit in a plane and a displacement amount at which the additional mass unit is displaced by Coriolis force acting on the additional mass unit when an angular velocity is applied around an axis orthogonal to the plane. Both the detecting section for detection is composed of electrodes having a comb tooth structure.

[0003]

Although such an angular velocity sensor can realize a relatively thin structure, it has a comb-teeth structure in which electrodes are opposed to each other for driving, and is driven by a suction force acting on these electrodes. Must. Therefore, these electrodes must be formed with extremely small gaps and high precision.

In order to detect a weak signal with high accuracy, not only the electrodes having opposing comb teeth must be formed with extremely small gaps and high precision, but also the opposing comb teeth must be formed. Had to be provided in large numbers.

[0005] The present invention is to solve this problem,
It is an object of the present invention to provide a thin and highly sensitive angular velocity sensor without forming a highly accurate comb-shaped electrode for driving and detection.

[0006]

A base provided in an XY plane and a first tuning fork comprising at least a pair of tuning forks extending from the base in a direction opposite to the Y-axis direction in the XY plane. A second tuning fork portion comprising at least a pair of tuning fork pieces extending in the Y-axis direction from the base so as to face the first tuning fork portion; and a pair forming the first tuning fork portion. A pair of at least one or more bending vibrating reeds between the tuning fork pieces and extending from the base in a direction opposite to the Y-axis direction, and a pair forming the second tuning fork part. A second bending vibrating part comprising at least one bending vibrating piece extending in the Y-axis direction from the base so as to be between the formed tuning fork pieces and to face the first bending vibrating part; The tuning fork pieces constituting the first and second tuning fork portions are represented by X
A driving means provided on the tuning fork piece to bend and vibrate in a direction opposite to the axial direction or the X-axis direction; In order to detect the deformation amount of the bending vibrating piece that bends and deforms in the X-axis direction or the direction opposite to the X-axis direction so as to keep balance with the bending deformation of the tuning fork piece that changes according to the magnitude of the working Coriolis force. Detecting means provided on the bending vibration piece. According to this configuration, a thin and highly sensitive angular velocity sensor can be obtained without forming a highly accurate comb-shaped electrode for driving and detection.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is characterized in that a base provided in the XY plane and at least a pair of bases extending from the base in the XY plane in a direction opposite to the Y-axis direction. A first tuning fork portion comprising a tuning fork piece, a second tuning fork portion comprising at least a pair of tuning fork pieces extending in the Y-axis direction from the base so as to face the first tuning fork portion; A first bending vibrating portion comprising at least one or more bending vibrating reeds between a pair of tuning fork pieces constituting the tuning fork portion and extending from the base in a direction opposite to the Y-axis direction; At least one bending vibrating piece extending between the pair of tuning fork pieces constituting the second tuning fork portion and extending in the Y-axis direction from the base so as to face the first bending vibrating portion; A second bending vibrating portion comprising the first and second
When an angular velocity about the Z axis is applied, a driving means provided on the tuning fork piece for bending and vibrating the tuning fork piece constituting the tuning fork portion in the X-axis direction or a direction opposite to the X-axis direction is applied.
The bending deformation in the X-axis direction or the direction opposite to the X-axis direction so as to keep balance with the bending deformation of the tuning fork piece that changes according to the magnitude of the Coriolis force acting in the direction opposite to the axial direction or the Y-axis direction. Since it is provided with a detecting means provided on the bending vibrating piece for detecting the amount of deformation of the bending vibrating piece, it is possible to reduce the thickness without forming a highly accurate comb-shaped electrode for driving and detecting. This has the effect of increasing sensitivity.

According to a second aspect of the present invention, in the first aspect of the present invention, a pair of tuning fork pieces constituting the first and second tuning fork portions are set in the X-axis direction or the X-axis direction from the respective tips. In either one of the opposite directions, the tuning fork pieces on both sides with respect to the respective symmetry axes of the first and second tuning forks are opposite to each other and on the same side. In this case, a first additional mass portion is formed so as to extend in the same direction, and one bending vibrating piece constituting each of the first and second bending vibrating portions is on a symmetry axis of the tuning fork portion. Since the second additional mass portion is formed so as to protrude from the tip of each bending vibration piece in the X-axis direction and the direction opposite to the X-axis direction, the tuning fork portion can be operated even with a small angular velocity input. The amount of deformation increases, and in response to this, the amount of deformation of the bending vibration part also increases, and the detection signal Has the effect that it becomes easy to adjust the respective resonance frequencies of the bending vibration unit tuning fork portion by adjusting the same time adding parts by mass attained is higher sensitivity.

According to a third aspect of the present invention, in the first or second aspect, the resonance frequencies of the first and second tuning forks are made close to the resonance frequencies of the first and second bending vibration parts. With such a configuration, the detection signal can be made more sensitive.

According to a fourth aspect of the present invention, in the first or second aspect of the invention, each detection signal detected by the detection means provided in the first and second bending vibration portions is subjected to differential detection processing. Since the processing circuit for performing the processing is connected to the detection means, it has an effect that a disturbance signal based on acceleration components applied from three directions of the X-axis, the Y-axis, and the Z-axis can be removed.

According to a fifth aspect of the present invention, in the first aspect of the present invention, the base, the first and second tuning forks, and the first and second bending vibrating portions provided in the XY plane are provided. Since the structure is formed integrally with the piezoelectric material, the structure has an effect that the integrated structure can be formed extremely easily from a flat plate having uniform piezoelectric characteristics.

According to a sixth aspect of the present invention, in the second aspect of the present invention, the base, the first and second tuning forks, the first and second bending vibrating portions, and the first and second bending fork portions provided in the XY plane are provided. Since the first and second additional mass portions are integrally formed of a piezoelectric material, they have an effect that an integrated structure can be formed very easily from a flat plate having uniform piezoelectric characteristics.

According to a seventh aspect of the present invention, in the first aspect, the base provided in the XY plane, the first and second tuning forks, and the first and second bending vibrating portions are provided. A layer made of a constant elastic metal material, an oxide material, or a high elastic polymer material, and a layer made of a piezoelectric material on at least the XY plane of the first and second tuning forks and the first and second bending vibration parts Is provided, so that a material having a high Q as a mechanical vibration characteristic and a piezoelectric material having a large piezoelectric constant can be freely combined.

According to an eighth aspect of the present invention, in the second aspect of the present invention, the base, the first and second tuning forks, the first and second bending vibrating portions, and the first and second tuning fork portions provided in the XY plane are provided. The first and second additional mass portions are formed of a constant elastic metal material, an oxide material or a high elastic polymer material, and at least the first and second mass portions are formed.
Since a layer made of a piezoelectric material is provided on the XY plane of the tuning fork portion and the first and second bending vibration portions, a material having a high Q as a mechanical vibration characteristic and a large piezoelectric constant are provided. This has the effect that the piezoelectric materials can be freely combined.

According to a ninth aspect of the present invention, a base provided in the XY plane, a vibrating piece extending from the base in the XY plane in a direction opposite to the Y-axis direction, An additional mass portion formed to extend in at least one of the X-axis direction and a direction opposite to the X-axis direction, and the vibrating piece is moved in the X-axis direction or a direction opposite to the X-axis direction; A driving means provided on the vibrating reed for bending vibration, and changes in accordance with the magnitude of Coriolis force acting in the Y-axis direction or the direction opposite to the Y-axis direction when an angular velocity around the Z-axis is applied. A detecting means provided on the vibrating reed and also serving as the driving means for detecting an increase or decrease in the amplitude of the bending vibration in the X-axis direction or in a direction opposite to the X-axis direction of the vibrating reed; High precision comb structure for driving, detection and Has an effect of not only attained be thinned and high sensitivity, the detection signal resulting from the application of the angular velocity to the driving voltage for driving the vibration piece becomes detectable in a state of superposition without forming a pole.

According to a tenth aspect of the present invention, in the ninth aspect of the present invention, the base, the resonator element, and the additional mass provided in the XY plane are formed integrally with a piezoelectric material. In addition, it is possible to very easily form an integrated structure from a flat plate having uniform piezoelectric characteristics.

According to an eleventh aspect of the present invention, in the ninth aspect of the present invention, the base, the vibrating piece and the additional mass provided in the XY plane are made of a constant elastic metal material, an oxide material or a high elastic high material. Since a layer made of a piezoelectric material is provided at least on the XY plane of the resonator element, a material having a high Q as a mechanical vibration characteristic and a piezoelectric material having a large piezoelectric constant can be freely used. Has the effect of being able to be combined with.

According to a twelfth aspect of the present invention, there is provided a vibrating reed extending in the Y-axis direction and one or both directions of the X-axis direction or the direction opposite to the X-axis direction from both ends of the vibrating reed. And an XY of one of the vibrating bars for supporting the vibrating bar symmetrically on the Y-axis.
The first and second support points provided on the surface, the third and fourth support points provided on the other XY surface of the vibrating element, and the first and third support points on the same straight line. And the first and third support portions extending in the Z-axis direction and the direction opposite to the Z-axis direction, respectively, and the Z-axis direction so as to be on the same straight line from the second and fourth support points. And the second and fourth support portions extending in directions opposite to the Z-axis direction, respectively, and the vibrating reed is formed by using the first, second, third, and fourth support points as nodes of vibration.
A driving means provided on the vibrating reed for bending vibration in a primary mode in a plane, and a Coriolis force acting in a Y-axis direction or a direction opposite to the Y-axis direction when an angular velocity around the Z-axis is applied. Detecting means serving also as the driving means provided on the vibrating piece for detecting an increase or decrease in the amplitude of the bending vibration in the X-axis direction or the direction opposite to the X-axis direction of the vibrating piece that changes according to the magnitude. In addition to achieving high-sensitivity and low-profile without forming electrodes with high-precision comb-tooth structure for driving and detection, due to the application of angular velocity to the driving voltage for driving the resonator element This has the effect that detection can be performed in a state where the detected signal is superimposed.

According to a thirteenth aspect of the present invention, in the invention according to the twelfth aspect, since the vibrating reed and the additional mass portion are integrally formed of a piezoelectric material, the vibrating reed and the additional mass portion are extremely formed from a flat plate having uniform piezoelectric characteristics. It has an effect that an integral structure can be easily formed.

According to a fourteenth aspect of the present invention, in the twelfth aspect, the vibrating reed and the additional mass portion are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and Since a layer made of a piezoelectric material is provided on the XY plane of the piece, it is possible to freely combine a material having a high Q as a mechanical vibration characteristic and a piezoelectric material having a large piezoelectric constant. Has an action.

According to a fifteenth aspect of the present invention, a base provided in the XY plane, a pair of tuning fork pieces extending from the base in the XY plane, and an X-axis direction from each tip of the pair of tuning fork pieces. Alternatively, an additional mass portion formed so as to extend in one of the directions opposite to the X-axis direction, and the pair of tuning forks are vibrated in the X-axis direction or in the direction opposite to the X-axis direction. And a driving means provided on the pair of tuning fork pieces, and when the angular velocity about the Z axis is applied, the driving means changes according to the magnitude of the Coriolis force acting in the Y axis direction or the direction opposite to the Y axis direction. A detecting unit that is also used as the driving unit provided on the pair of tuning fork segments to detect an increase or decrease in the amplitude of the bending vibration of the pair of tuning fork segments in the X-axis direction or the direction opposite to the X-axis direction. High accuracy comb for driving and detection Not only it attained is thinned and high sensitivity without forming the electrode structure, has the effect that the detection signal due to the application of the angular velocity to the driving voltage for driving the vibration piece becomes detectable in a state of superposition.

According to a sixteenth aspect of the present invention, in the invention according to the fifteenth aspect, the base, a pair of tuning fork pieces and the additional mass portion provided in the XY plane are integrally formed of a piezoelectric material. Therefore, it has an effect that an integrated structure can be formed extremely easily from a flat plate having uniform piezoelectric characteristics.

According to a seventeenth aspect of the present invention, in the fifteenth aspect of the present invention, the base, the pair of tuning fork pieces and the additional mass provided in the XY plane are made of a constant elastic metal material, an oxide material, Since a layer made of an elastic polymer material and a layer made of a piezoelectric material is provided on at least the XY plane of the pair of tuning fork pieces, a material having a high Q as a mechanical vibration characteristic and a large piezoelectric constant This has the effect that the piezoelectric materials can be freely combined.

[0024] The invention according to claim 18 is characterized in that a base provided in the XY plane, at least one pair of tuning fork pieces extending in the Y-axis direction from the base in the XY plane, and a pair of tuning fork pieces forming the pair. Both the tuning fork piece on the X-axis direction side and the tuning fork piece on the side opposite to the X-axis direction with respect to the axis of symmetry are either in the X-axis direction or the direction opposite to the X-axis direction from each tip. An additional mass portion formed in one direction and on the same side so as to extend in the same direction, and at least between the pair of tuning fork pieces and extending in the Y-axis direction from the base portion. One or more bending vibration pieces, a driving means provided on the tuning fork piece for bending and vibrating the tuning fork piece in the X-axis direction or a direction opposite to the X-axis direction, and an angular velocity about the Z-axis are applied. At the time, the core that works in the Y-axis direction or the direction Detecting the amount of deformation of the bending vibrating piece that bends and deforms in the X-axis direction or in the direction opposite to the X-axis direction so as to keep balance with the bending deformation of the tuning fork piece that changes according to the magnitude of the orienting force. The provision of the detecting means provided on the bending vibrating reed has an effect that thinning and high sensitivity can be achieved without forming a highly accurate comb-shaped electrode for driving and detecting.

According to a nineteenth aspect of the present invention, in the eighteenth aspect, the base, the tuning fork piece, the additional mass part, and the bending vibration piece provided in the XY plane are integrally formed of a piezoelectric material. With such a configuration, an effect is obtained that an integrated structure can be formed extremely easily from a flat plate having uniform piezoelectric characteristics.

According to a twentieth aspect of the present invention, in the eighteenth aspect, the base, the tuning fork piece, the additional mass part and the bending vibrating piece provided in the XY plane are made of a constant elastic metal material, an oxide material. Alternatively, since a layer made of a piezoelectric material is provided at least on the XY plane of the tuning fork piece and the bending vibrating piece, the material having a high Q as a mechanical vibration characteristic is used. This has an effect that a piezoelectric material having a large piezoelectric constant can be freely combined.

According to a twenty-first aspect of the present invention, there are provided a first support portion formed so as to connect two base portions provided in the XY plane and the base portions in the XY plane in the Y-axis direction. And second and third support portions extending in the X-axis direction and in a direction opposite to the X-axis direction from the central portion of the first support portion, and in the Y-axis direction and from the tip of the second support portion. First and second vibrating reeds extending in a direction opposite to the Y-axis direction, and third and fourth vibrating pieces extending in a Y-axis direction and in a direction opposite to the Y-axis direction from a tip of the third support portion. And the first, second, third,
An additional mass portion formed to extend from each end of the fourth vibrating piece in one of the X-axis direction and a direction opposite to the X-axis direction, and a positive or negative drive signal Then, the first and second vibrating bars are vibrated in the X-axis direction or a direction opposite to the X-axis direction, and the third and fourth vibrating bars are moved in directions opposite to the first and second vibrating bars. Driving means provided on the first, second, third, and fourth vibrating reeds to simultaneously vibrate, and when an angular velocity about the Z axis is applied, the Y axis direction or a direction opposite to the Y axis direction Detecting the amount of increase or decrease in the amplitude of the bending vibration of the first, second, third, and fourth vibrating pieces in the X-axis direction or in the direction opposite to the X-axis direction, which changes depending on the magnitude of the Coriolis force acting on the vibrating piece. The first, second, third, and fourth vibrating reeds are provided with detecting means that also serves as the driving means. Therefore, not only is it possible to reduce the thickness and increase the sensitivity without forming a highly accurate comb-shaped electrode for driving and detection, but also to detect signals caused by the application of an angular velocity to the driving voltage for driving the resonator element. Has the effect of being detectable in a state where is superimposed.

According to a twenty-second aspect, in the twenty-first aspect, the base, the first, second, and third support portions, the first, second, and third portions provided in the XY plane are provided. Since the fourth vibrating reed and the additional mass portion are integrally formed of a piezoelectric material, the fourth vibrating reed and the additional mass portion have an effect that an integrated structure can be extremely easily formed from a flat plate having uniform piezoelectric characteristics.

According to a twenty-third aspect of the present invention, in the twenty-first aspect, the base, the first, second, and third support portions, the first, second, and third portions provided in the XY plane are provided. , The fourth vibrating reed and the additional mass portion are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and at least on the XY plane of the first, second, third, and fourth vibrating reeds. Has a structure in which a layer made of a piezoelectric material is provided, and thus has an effect that a material having a high Q as a mechanical vibration characteristic and a piezoelectric material having a large piezoelectric constant can be freely combined.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
This will be described with reference to FIG.

(Embodiment 1) FIG. 1 is a plan view for explaining a first embodiment of an angular velocity sensor according to the present invention. In FIG. 1, the driving direction is the X axis direction, the direction in which the Coriolis force is generated is the Y axis, and the input axis of the angular velocity Ω is the Z axis.
In FIG. 1, reference numeral 1 denotes a base made of a quartz plate serving as a piezoelectric body having a thickness (Z-axis direction) of 0.2 mm, a length (Y-axis direction) of 20 mm, and a width (X-axis direction) of 13.3 mm.

From the base 1, the first and second
The first tuning fork portions 2a and 2b extend to form a first tuning fork portion,
Third and fourth tuning fork pieces 3a, 3 from the base 1 in the Y-axis direction so as to face the first and second tuning fork pieces 2a, 2b, respectively.
b extends to form a second tuning fork. 1st, 2nd
The first and second additional masses 4a and 4b extend from the tips of the tuning fork pieces 2a and 2b so as to be symmetrical in the X-axis direction and the direction opposite to the X-axis direction, respectively. Similarly, third and fourth additional masses 5a and 5b extend from the tips of the third and fourth tuning fork pieces 3a and 3b so as to be symmetrical in the X-axis direction and the direction opposite to the X-axis direction, respectively. , First, second, third, fourth
The first additional mass portion is constituted by the additional masses 4a, 4b, 5a, 5b.

From the base 1 on the axis of symmetry of the first tuning fork portion (that is, passing between the first and second tuning fork pieces 2a and 2b), Y
The first bending vibration piece 6 extends in the direction opposite to the axial direction,
Is formed. Also from the base 1 on the axis of symmetry of the second tuning fork (ie, the third and fourth tuning fork pieces 3).
The second bending vibration piece 7 extends in the Y-axis direction (passing between a and 3b) to form a second bending vibration part. Fifth and sixth additional masses 8 and 9 are provided so as to protrude from the respective ends of the first and second bending vibration pieces 6 and 7 in the X-axis direction and in the direction opposite to the X-axis direction. A mass part is constituted. Base 1, first, second, third, fourth tuning fork pieces 2a, 2b, 3
a, 3b, first, second, third, fourth, fifth, sixth additional masses 4a, 4b, 5a, 5b, 8, 9, first and second bending vibration pieces 6, 7 Both are formed integrally from a single quartz plate. Four corners of the base 1 formed of one quartz plate are used as fixing portions for fixing with a small area.
0.2 holes 10a, 10b, 10c, and 10d are formed.

In the vicinity of the holes 10a, 10b, 10c, and 10d, L-shaped slits 11a, 11b, 11c, and 11d for obtaining a mechanical damping effect are provided at predetermined positions.

On each XY plane (front side) of the second and fourth tuning fork pieces 2b and 3b, a driving electrode 1 for constituting driving means is provided.
2a and 13a are provided. First and third tuning fork pieces 2
On each of the XY planes (a front surface side) of a and 3a, detection electrodes 14a and 15a for constituting detection means for monitoring are provided. On the XY plane (front side) of the first and second bending vibration pieces 6 and 7, detection electrodes 16 a and 17 a for constituting detection means for detecting bending deformation due to Coriolis force caused by application of angular velocity. Is provided.

FIG. 2 is a cross-sectional view of the second tuning fork piece 2b provided with the drive electrode, cut along the XZ plane. In FIG.
The arrow pointing in the X-axis direction indicates the electric axis of the second tuning fork piece 2b made of quartz, and 12b is the XY surface of the second tuning fork piece 2b so as to face the drive electrode 12a with the second tuning fork piece 2b interposed therebetween. Drive electrodes provided on the upper side (back side). 18 is the second
A pair of common electrodes is provided on the YZ plane (side surface) of the tuning fork piece 2b so as to face the second tuning fork piece 2b. 19 is an output signal source of the drive circuit.

Similarly to the second tuning fork piece 2b, the fourth tuning fork piece 3b is provided with drive electrodes 13a and 13b and a common electrode 18.

Next, the driving principle of the second tuning fork piece 2b will be briefly described. Assuming that the output signal source 19 is
When a positive voltage is applied to a and 12b, the direction of the electric field is directed in the direction of the dashed arrow shown in FIG. This allows the second
The ab side of the tuning fork piece 2b is compressed and the cd side is expanded. When a negative voltage is applied to the drive electrodes 12a and 12b, the ab side of the second tuning fork piece 2b expands and the cd side compresses.

By repeating these steps continuously, the second tuning fork piece 2b vibrates in the XY plane in the primary mode.

According to the same driving principle, the fourth tuning fork piece 3b
Also vibrate in the first-order mode in the XY plane. When the second and fourth tuning fork pieces 2b and 3b vibrate in the primary mode, the first,
The third tuning fork pieces 2a and 3a also resonate and start tuning fork vibration in the XY plane.

FIG. 3 is a cross-sectional view of the first tuning fork piece 2a provided with a detection electrode for monitoring cut along the XZ plane. X
The arrow pointing in the axial direction indicates the electric axis of the first tuning fork piece 2a made of quartz crystal as in FIG. 2, and 14b indicates the first tuning fork piece 2a.
Is a monitoring detection electrode provided on the XY surface (back side) of the first tuning fork piece 2a so as to face the detection electrode 14a for monitoring with the detection electrode 14a interposed therebetween. Reference numeral 18 is a common electrode as in FIG.

Similarly to the first tuning fork piece 2a, the third tuning fork piece 3a is also provided with detection electrodes 15a and 15b for monitoring and a common electrode 18.

Next, the monitoring detection electrodes 14a, 14
b, the charge appearing on the common electrode 18 will be briefly described.

Since the first tuning fork piece 2a oscillates with the second tuning fork piece 2b shown in FIG. 2, the first tuning fork piece 2a is compressed when the ab side of the second tuning fork piece 2b is compressed. G
The h side compresses.

When the cd of the second tuning fork 2b is extended, the ef side of the first tuning fork 2a is extended.

By these compression and expansion, positive charges are generated on the monitoring detection electrodes 14a and 14b, and the common electrode 1
8, a negative charge is generated. Therefore, in the first tuning fork piece 2a, when the ef side is compressed and the gh side is expanded, negative charges are generated on the monitoring detection electrodes 14a and 14b,
A positive charge is generated on the common electrode 18.

FIG. 4 is a block diagram showing the connection between the angular velocity sensor of the present invention and its drive and detection circuit. In FIG. 4, reference numeral 20 denotes a differential input type charge amplifier. The differential input type charge amplifier 20 amplifies signals obtained from the detection electrodes 16a and 17a provided on the first and second bending vibration pieces 6 and 7, respectively, and shifts the signals by 90 °. is there. 21 is a detection circuit. Detection circuit 2
In step 1, the output signal of the charge amplifier 20 is synchronously detected. Reference numeral 22 denotes a low-pass filter as a smoothing circuit for smoothing the detection signal obtained by the detection circuit 21.
23 is a sum input type driving circuit for driving the second and fourth tuning fork pieces 2b and 3b. Detection electrode 1 for monitoring
The first, second, third, and fourth signals are input to the driving circuit 23 by inputting the signals obtained from 4a, 14b, 15a, and 15b.
Target the tuning fork vibrating bars 2a, 2b, 3a, 3b
Feedback control is performed so as to have a vibration amplitude of μm.
FIG. 5 shows that the first and third tuning fork pieces 2a and 3a are arranged in the X-axis direction.
When the second and fourth tuning fork pieces 2b and 3b are driven and deformed in the direction opposite to the X-axis direction, the first, second, third and fourth when the angular velocity around the Z-axis is applied. Tuning fork pieces 2a, 2b, 3
FIGS. 7A and 7B are schematic diagrams illustrating examples of modified forms of the first and second bending vibration pieces 6 and 7. FIGS.

As shown in FIG. 5, when the angular velocity around the Z axis is applied, the first and third additional masses 4a, 5a
, A Coriolis force acts intensively on the second and fourth additional masses 4b, 5b in a direction opposite to the Y-axis direction, and the Coriolis force causes the first, second, third, and the like. The symmetry of the vibration amplitude of the fourth tuning fork pieces 2a, 2b, 3a, 3b is broken 1
The next mode is modified. The first bending vibrating piece 6 is moved in the X-axis direction so as to correct the stress state of the first, second, third, and fourth tuning fork pieces 2a, 2b, 3a, 3b in which the symmetry is broken and to maintain the balance. The second bending vibration piece 7 is deformed in the X-axis direction. Since these deformations correspond to the magnitude of the applied angular velocity, the detection electrodes 16a, 1 provided on the first and second bending vibration pieces 6, 7, respectively.
7a, it is detected as a charge amount corresponding to the magnitude of the applied angular velocity. Since the first, second, third, and fourth additional masses 4a, 4b, 5a, and 5b are provided, the amount of deformation of the first and second tuning forks increases even with a small angular velocity input. Not only that, the deformation efficiency of the first and second bending vibration pieces 6 and 7 provided with the fifth and sixth additional masses 8 and 9 is improved. With these configurations, the sensitivity of the detection signal can be further increased, and at the same time, the additional masses 4a, 4b, 5
The adjustment of the resonance frequencies of the first and second tuning fork portions and the first and second bending vibration portions is also facilitated by the adjustment of a, 5b, 8, and 9.

FIG. 6 is a cross-sectional view of the first bending vibration piece 6 provided with the detection electrode 16a between the first and second tuning fork pieces 2a and 2b, cut along the XZ plane. In FIG. 6, X
The arrow pointing in the axial direction indicates the electric axis of the first bending vibration piece 6 made of quartz, and 16b is on the XY plane of the first bending vibration piece 6 so as to face the detection electrode 16a with the bending vibration piece 6 interposed therebetween. (The back side). Reference numeral 18 denotes the first bending vibration piece 6 on the YZ plane (side face) of the first bending vibration piece 6.
And a pair of common electrodes provided to face each other.

Similarly, the second bending vibration piece 7 between the third and fourth tuning fork pieces 3a and 3b is also provided with the second bending vibration piece 7
The detection electrode 17a is opposed to the detection electrode 17a with the
b is provided, and a pair of common electrodes 18 is provided on the YZ plane (side surface) so as to face each other with the second bending vibration piece 7 interposed therebetween.

Next, when the first and second bending vibrating pieces 6 and 7 are deformed as shown in FIG.
The state of generation of electric charges appearing on 6b, 17a, 17b and common electrode 18 will be briefly described.

Since the ij side of the first bending vibrating piece 6 between the first and second tuning fork pieces 2a and 2b is compressed and the kl side is expanded, negative charges are generated on the detecting electrodes 16a and 16b. And
A positive charge is generated on the common electrode 18. In addition, the third and fourth
I of the second bending vibration piece 7 between the tuning fork pieces 3a and 3b
Since the j side expands and the kl side compresses, the detection electrode 17
Positive charges are generated at a and 17b, and negative charges are generated at the common electrode 18.

The charges obtained from the detection electrodes 16a and 16b and the charges obtained from the detection electrodes 17a and 17b are differentially amplified by the charge amplifier 20, so that a double output is obtained. As described above, according to the configuration of the present embodiment, not only the thickness can be reduced without forming a highly accurate comb-shaped electrode for driving and detection, but also the additional mass is provided, so that a small angular velocity input can be performed. On the other hand, the amount of deformation of the tuning fork becomes large, and the amount of deformation of the bending vibrating part also becomes large correspondingly, so that the sensitivity of the detection signal can be further increased. In addition, there is an effect of eliminating the influence of electric charge and temperature generated by unnecessary components (acceleration applied from each direction) other than the angular velocity.

In the present embodiment, the resonance frequency of the first mode of the first, second, third, and fourth tuning fork pieces 2a, 2b, 3a, 3b and the first and second bending vibration pieces 6, 7 By bringing the resonance frequencies of the first-order modes closer to each other, the detection sensitivity is increased.

In this embodiment, the slit 11
Since a, 11b, 11c, and 11d are provided on the base 1, disturbance vibration is generated by the first and second bending vibrating pieces 6,7.
This has the effect of preventing the primary mode bending vibration from being mixed. In addition, it also has a function of preventing the primary mode bending vibration of the first and second bending vibration pieces 6 and 7 from leaking to the base 1.

In the present embodiment, the base 1, the first,
Second, third, and fourth tuning fork pieces 2a, 2b, 3a, 3b, first, second, third, fourth, fifth, and sixth additional masses 4a, 4
b, 5a, 5b, 8, 9 and the first and second bending vibration pieces 6,
Although an example in which each is integrally formed from a single quartz plate has been described, a single crystal material or a polycrystalline material may be used as long as the material has piezoelectricity.

In the present embodiment, the configuration in which the additional mass is provided outward from each tip of the first, second, third, and fourth tuning fork pieces 2a, 2b, 3a, 3b has been described. In the configuration in which the additional mass is provided inward from each tip or in the first and second tuning fork pieces 2a and 2b, the additional mass is made outward, and in the third and fourth tuning fork pieces 3a and 3b, the additional mass is added. Various configurations are possible, such as providing inward.

In this embodiment, the first, second, third, and fourth tuning fork pieces 2a, 2b, 3a, 3b and the tips of the first and second bending vibrating pieces 6, 7 are provided. Although the configuration in which the additional mass is provided in each case has been described, there are various configurations such as a configuration in which neither the tuning fork piece nor the bending vibration piece has the additional mass, or a method in which the additional mass is provided only in the tuning fork piece or the bending vibration piece only. Various configurations are possible.

Further, in this embodiment, a pair of tuning fork pieces are provided in the first and second tuning fork portions, and one bending vibrating piece is provided between each of the first and second tuning fork portions. Although the configuration in which the bending vibration portion is provided has been described, a configuration in which a pair or a plurality of pairs of tuning fork pieces and one or a plurality of bending vibration pieces are appropriately combined and provided is of course possible.

(Embodiment 2) FIG. 7 is a plan view illustrating an angular velocity sensor according to a second embodiment of the present invention. 7, the same components as those in FIG. 1 are denoted by the same reference numerals, detailed description thereof will be omitted, and only different portions will be described in detail. In FIG. 7, the base 30, the first, second, third,
The fourth tuning fork pieces 31a, 31b, 32a, 32b, the first,
The second, third, and fourth additional masses 33a, 33b, 34a,
34b, the first and second bending vibration pieces 35 and 36 and the fifth and sixth additional masses 37 and 38 are described in the first embodiment, except that they are integrally formed of a constant elastic metal. The shape and dimensions shown in FIG. 1 are the same.

XY of the second and fourth tuning fork pieces 31b and 32b
Piezoelectric ceramics 39 and 40 for driving in the primary mode are joined on the surface. Piezoelectric ceramics 41 and 42 for monitoring are bonded on the XY plane of the first and third tuning fork pieces 31a and 32a. Piezoelectric ceramics 43, 44 for detecting the amount of charge corresponding to the magnitude of the angular velocity are joined to the XY plane (front side) of the first and second bending vibration pieces 35, 36.

In FIG. 7, the first, second, third, and fourth tuning fork pieces 31a, 31b, 32a, 32b, the first and second bending vibrating pieces 35, 36 are deformed, and the piezoelectric body is monitored. The tendencies of the electric charges generated in the ceramics 41 and 42 and the electric charges generated in the piezoelectric ceramics 43 and 44 when the angular velocity around the Z axis is applied are the same as those in the first embodiment.

In this embodiment, the base 30, the first, second, third, and fourth tuning fork pieces 31a, 31b, 32
a, 32b, the first, second, third, fourth, fifth, and sixth additional masses 33a, 33b, 34a, 34b, 37, 38 and the first and second bending vibration pieces 35, 36 are configured. Material and piezoelectric ceramics 39, 40, 41, 42, 43, 4
4 are made of different materials, it is possible to freely combine a material having a high Q as a mechanical vibration characteristic and a piezoelectric material having a large piezoelectric constant.

In this embodiment, an example in which piezoelectric ceramics are joined for driving, for monitoring, and for detecting the amount of electric charge corresponding to the magnitude of the printed angular velocity has been described. If so, various thin film configurations can be adopted.

(Embodiment 3) FIG. 8 is a plan view for explaining a third embodiment of the angular velocity sensor according to the present invention. 8, the driving direction is the X-axis direction, the direction in which the Coriolis force is generated is the Y-axis, and the input axis of the angular velocity Ω is the Z-axis.

In FIG. 8, reference numeral 50 denotes a thickness (in the Z-axis direction).
A base made of a piezoelectric ceramic having a size of 0.5 mm, a length (Y-axis direction) of 15 mm, and a width (X-axis direction) of 15 mm, 51
Has a thickness (Z-axis direction) of 0.5 mm extending from the base 50 in a direction opposite to the Y-axis direction, and a length of 15 m in the Y-axis direction.
m, a vibrating piece made of a piezoelectric ceramic having a width of 3.5 mm (X-axis direction), 52 having a thickness (Z-axis direction) of 0.5 mm extending from the tip of the vibrating piece 51 in a direction opposite to the X-axis direction, This is an additional mass portion made of piezoelectric ceramics having a length of 5 mm and a width (Y-axis direction) of 3.5 mm. On the XY plane (front side) of the vibrating reed 51, electrodes 53a and 54a are provided at both ends in the width direction to constitute driving means and detecting means, respectively.

FIG. 9 is a cross-sectional view of the resonator element 51 provided with the electrodes 53a and 54a cut along the XZ plane. In FIG. 9, the arrow pointing in the Z-axis direction indicates the polarization direction of the vibrating piece 51 made of piezoelectric ceramics, and 53b and 54b denote the XY plane of the vibrating piece 51 so as to face the electrodes 53a and 54a with the vibrating piece 51 interposed therebetween. This is a common electrode provided on the upper side (back side). 55 is an output signal source of the drive circuit.

Next, the driving principle of the resonator element 51 will be briefly described. If positive and negative voltages are respectively applied to the electrodes 53a and 54a from the output signal source 55, the side of the vibrating reed 51 where the electrodes 53a and 53b are provided extends in the Y-axis direction, and the electrodes 54a and 54a. The side provided with 54b is Y
Compress axially. When negative and positive voltages are applied to the electrodes 53a and 54a, respectively, the side of the vibrating piece 51 where the electrodes 53a and 53b are provided is compressed in the Y-axis direction, and the electrodes 54a and 54b are provided. The extending side extends in the Y-axis direction.

By repeating these steps continuously, the resonator element 51 vibrates in the XY plane in the primary mode.

FIG. 10 is a block diagram in which the angular velocity sensor of the present invention and its driving and detecting circuit are connected. FIG.
When the vibrating piece 51 is being driven and deformed in the X-axis direction, FIG.
FIG. 9 is a schematic diagram for explaining an example of a modified form of the resonator element 51 when an angular velocity around the Z axis as shown in FIG. FIG. 12 is an explanatory diagram of a voltage change state at points A and B when an angular velocity around the Z axis as shown in FIG. 10 is applied when the resonator element 51 is being driven and deformed in the X axis direction. It is.
11 and 12, a solid line indicates a case where no angular velocity is applied, and a broken line indicates a case where angular velocity is applied. FIG.
At 0, 56 is a self-excited oscillation drive circuit, 57 and 58 are resistors, and 59 is an addition amplifier as a detection circuit. The self-excited oscillation type driving circuit 56 connects the electrodes 5 through the resistors 57 and 58.
By supplying voltages of opposite phases to 3a and 54a, continuous vibration is generated as described above. As shown in FIG. 11, the electrodes 53a and 54a of the resonator element 51 have positive polarity, respectively.
In a state where the negative electrode voltage is applied and the vibrating piece 51 is vibrated, if an angular velocity around the Z axis as shown in FIG. 10 is applied, the Coriolis is concentrated on the additional mass portion 52 in the direction opposite to the Y axis direction. A force is applied to extend the side of the vibrating reed 51 on which the electrodes 53a and 53b are provided in the Y-axis direction.
The side provided with 54b is deformed to be compressed in the Y-axis direction. Due to such deformation, the electrodes 53a, 53
The z-axis direction side of the resonator element 51 provided with “b” is more compressed and has higher impedance. Conversely, the electrodes 54a, 54
The Z-axis direction side of the resonator element 51 provided with “b” further extends and has a lower impedance. These changes are shown in FIG.
FIG. 12 shows a state captured as a change in voltage at points A and B shown in FIG.

By applying the voltages at the points A and B to the addition amplifier 59, a final output corresponding to the magnitude of the applied angular velocity can be obtained.

According to the present embodiment, not only the thickness and sensitivity can be reduced without forming a highly accurate comb-shaped electrode for driving and detection, but also the application of angular velocity to the driving voltage for driving the resonator element. Can be detected in a state where the detection signal caused by the superimposition is superimposed.

In this embodiment, an example is described in which one vibrating piece and an additional mass provided at the tip of the vibrating piece are used. However, such a structure may be paired to form a tuning fork. It is possible. Thereby, when an angular velocity is applied, Coriolis forces in opposite directions act on both additional mass parts,
A double output signal is obtained. Furthermore, it is also possible to use two pairs of tuning forks to form an H-shaped configuration. Thereby, a further increase in the output signal can be expected. Further, as described in the first embodiment, a configuration in which the bending vibration piece is provided between the tuning forks (however, in a narrow sense that both the first and second tuning forks must be provided). Various configurations can be used, such as a configuration in which the presence or absence of an additional mass and the direction in which the additional mass is formed are taken into consideration.

(Embodiment 4) FIG. 13 is a perspective view illustrating an angular velocity sensor according to a fourth embodiment of the present invention. FIG. 14 is a schematic line for explaining an example of a deformed form of the vibrating bar when an angular velocity around the Z-axis as shown in FIG. 13 is applied while the vibrating bar is being driven and deformed in the XY plane. FIG. In FIG. 13, the driving direction is the X axis direction, the direction in which the Coriolis force is generated is the Y axis, and the input axis of the angular velocity Ω is the Z axis. In FIG. 14, a solid line indicates a case where no angular velocity is applied, and a broken line indicates a case where angular velocity is applied. In this embodiment, the basic technical idea is the same as that of the third embodiment in that detection can be performed in a state in which a detection signal resulting from the application of an angular velocity is superimposed on a driving voltage for driving the resonator element. Only different parts will be described in detail. FIG.
3, reference numeral 60 denotes a vibrating reed formed of piezoelectric ceramics extending in the Y-axis direction, and 61 and 62 denote the vibrating reeds 60.
The first and second additional mass portions 63a and 63b formed of piezoelectric ceramics extending from the opposite ends of the piezoelectric ceramic in the direction opposite to the X-axis direction and in the X-axis direction, respectively,
XY on one side of the vibrating piece 60 to support
The first and second support points 6 provided on the surface and near the first additional mass portion 61 and the second additional mass portion 62, respectively.
3c and 63d are third and fourth support points provided on the other XY plane of the vibrating piece 60 so as to face the first and second support points 63a and 63b, respectively, with the vibrating piece 60 interposed therebetween. 64a and 64b are both driving means and detection means provided between both ends of the vibrating piece 60 in the XY plane (front side) in the width direction (X-axis direction) and between the first additional mass portion 61 and the first support point 63a. First and second electrodes as means, 65a, 65b
Is the width direction (X-axis direction) of the XY plane (front side) of the resonator element 60
At both ends and the second additional mass portion 62 and the second support point 63b
The third and fourth electrodes 66 as a driving means and a detecting means provided between them are fixed parts, 67a, 67b, 6
Reference numerals 7c and 67d denote first, second, third and fourth support portions. The straight line connecting the first and third support points 63a and 63c is Z
The first and third support points 63a and 63c on the shaft and
The first and third support portions 67a and 67c extend in the Z-axis direction and the direction opposite to the Z-axis direction, respectively. The ends of the first and third support portions 67a and 67c Fixed. Second and fourth support points 63b, 6
The straight line connecting 3d is on the Z axis, and the second and fourth support portions 67b and 67d extend from the second and fourth support points 63b and 63d in the Z axis direction and the direction opposite to the Z axis direction, respectively. The ends of the second and fourth support portions 67b and 67d are fixed to the fixing portion 66, respectively.

A common electrode is provided on the XY plane (back side) of the resonator element 60 so as to face the first, second, third, and fourth electrodes 64a, 64b, 65a, and 65b with the resonator element 60 interposed therebetween. The first and third electrodes 64a and 65a have the same phase, and the second and fourth electrodes 64b and 65b have the same phase and first phase.
And the second electrodes 64a and 64b supply voltages so that the phases are opposite to each other, and the third and fourth electrodes 65a and 65b supply voltages so that the phases are opposite to each other.
The first-order mode bending vibration is continuously generated in the vibrating reed 60 in the XY plane with 63b as a node of vibration. As shown in FIG. 14, for example, the second and fourth electrodes 64b, 6 of the resonator element 60
When a positive voltage is applied to each of the electrodes 5a and 5b, and a negative voltage is applied to each of the first and third electrodes 64a and 65a to vibrate the vibrating piece 60, the Z axis as shown in FIG. When the angular velocity is applied, Coriolis force acts intensively in the Y-axis direction on the first additional mass portion 61, thereby extending the side of the resonator element 60 on which the second electrode 64b is provided in the Y-axis direction. , The side on which the first electrode 64a is provided is compressed in the Y-axis direction. In addition, Coriolis force acts on the second additional mass portion 62 intensively in the direction opposite to the Y-axis direction, and somewhat compresses the side of the resonator element 60 where the fourth electrode 65b is provided in the Y-axis direction. The deformation is such that the side on which the third electrode 65a is provided extends somewhat in the Y-axis direction. Due to such deformation, the second and third electrodes 64 are formed.
The impedance on the Z-axis direction side of the resonator element 60 provided with b and 65a is increased by being compressed. Conversely, the impedance on the Z-axis direction side of the resonator element 60 provided with the first and fourth electrodes 64a and 65b is reduced by being extended. By detecting these changes, a final output corresponding to the magnitude of the applied angular velocity is obtained. With this configuration, it is possible to reduce the thickness and increase the sensitivity without forming a highly accurate comb-shaped electrode for driving and detection, and to detect a signal generated by applying an angular velocity to the driving voltage for driving the resonator element. Can be detected in a state where is superimposed.

In the present embodiment, the Z of the resonator element 60
Although the case where the dimension in the axial direction is smaller than the dimension in the X-axis direction has been described, a configuration reverse to this is naturally possible.

In the present embodiment, the vibrating piece 60
And the first and second additional mass portions 61 and 62 have been described as being formed from an integral piezoelectric ceramic. However, they may be integrally formed by a quartz plate, or may be made of a constant elastic metal material, an oxide material, or a high elastic high material. A structure in which the vibrating reed and the first and second additional mass portions are integrally formed of a molecular material, and a piezoelectric ceramic is bonded on the vibrating reed or various thin films exhibiting piezoelectricity are formed on the surface. However, the technical idea of the present invention can naturally be achieved.

[0078]

As described above, the present invention is directed to a first embodiment comprising a base provided in the XY plane and at least one pair of tuning fork pieces extending from the base in the XY plane in a direction opposite to the Y-axis direction. , A second tuning fork portion comprising at least a pair of tuning fork pieces extending in the Y-axis direction from the base so as to face the first tuning fork portion, and the first tuning fork portion. A first bending vibrating part comprising at least one bending vibrating piece between the pair of tuning fork pieces and extending from the base in a direction opposite to the Y-axis direction, and the second tuning fork part; A second bending vibrating piece comprising at least one or more bending vibrating pieces extending between the paired tuning fork pieces and extending in the Y-axis direction from the base so as to face the first bending vibrating section;
A bending vibration portion, a driving means provided on the tuning fork piece for bending and vibrating the tuning fork pieces constituting the first and second tuning fork portions in the X-axis direction or a direction opposite to the X-axis direction; When an angular velocity around the axis is applied, the X-axis direction or the X-axis direction or the X-axis direction is maintained so as to keep a balance with the bending deformation of the tuning fork piece that changes according to the magnitude of the Coriolis force acting in the Y-axis direction or the direction opposite to the Y-axis direction. A detecting means provided on the bending vibrating piece for detecting a deformation amount of the bending vibrating piece that bends and deforms in a direction opposite to the axial direction, so that a highly accurate comb-tooth structure for driving and detecting is provided. A thin and highly sensitive angular velocity sensor can be obtained without forming the above electrodes.

[Brief description of the drawings]

FIG. 1 is a plan view illustrating an angular velocity sensor according to a first embodiment of the present invention.

FIG. 2 is an explanatory view in which a tuning fork piece provided with a drive electrode of the angular velocity sensor is cut along an XZ plane.

FIG. 3 is an explanatory view of a tuning fork piece provided with a detection electrode for monitoring of the angular velocity sensor cut along an XZ plane;

FIG. 4 is a block diagram in which the angular velocity sensor is connected to a drive circuit and a detection circuit.

FIG. 5 is a schematic view of a modified form of a tuning fork piece and a bending vibration piece when an angular velocity is applied to the angular velocity sensor.

FIG. 6 is an explanatory view in which a bending vibration piece provided with a detection electrode of the angular velocity sensor is cut along an XZ plane;

FIG. 7 is a plan view illustrating an angular velocity sensor according to a second embodiment of the present invention.

FIG. 8 is a plan view illustrating an angular velocity sensor according to a third embodiment of the present invention.

FIG. 9 shows a resonator element provided with electrodes of the same angular velocity sensor as X
Explanatory drawing cut in the Z plane

FIG. 10 is a block diagram in which the angular velocity sensor and its driving circuit and detection circuit are connected.

FIG. 11 is a schematic view of a modified form of a resonator element when an angular velocity is applied to the angular velocity sensor.

FIG. 12 shows A when an angular velocity is applied to the angular velocity sensor.
Explanatory drawing of the change state of the voltage at point B

FIG. 13 is a perspective view illustrating an angular velocity sensor according to a fourth embodiment of the present invention.

FIG. 14 is a schematic view of a modified form of a resonator element when an angular velocity is applied to the angular velocity sensor.

[Explanation of symbols]

1, 30, 50 Base 2a, 31a First tuning fork 2b, 31b Second tuning fork 3a, 32a Third tuning fork 3b, 32b Fourth tuning fork 4a, 33a First additional mass 4b, 33b 2 additional mass 5a, 34a 3rd additional mass 5b, 34b 4th additional mass 6, 35 1st bending vibration piece 7, 36 2nd bending vibration piece 8, 37 5th additional mass 9, 38th 6 Additional masses 10a, 10b, 10c, 10d Holes 11a, 11b, 11c, 11d Slits 12a, 12b, 13a, 13b Drive electrodes 14a, 14b, 15a, 15b Detection electrodes 16a, 16b, 17a, 17b for monitoring Detection electrodes for detecting angular velocity 18, 53b, 54b Common electrodes 19, 55 Output signal source of drive circuit 20 Charge amplifier 21 Detection circuit 22 Low-pass filter 23 Driving circuits 39, 40, 41, 42, 43, 44 Piezoelectric ceramics 51, 60 Vibrating piece 52 Additional mass section 53a, 54a Electrode 56 Self-excited oscillation driving circuit 57, 58 Resistance 59 Detection circuit 61 First additional mass section 62 second additional mass portion 63a first support point 63b second support point 63c third support point 63d fourth support point 64a first electrode 64b second electrode 65a third electrode 65b fourth Electrode 66 Fixing part 67a First supporting part 67b Second supporting part 67c Third supporting part 67d Fourth supporting part

Continued on the front page (72) Inventor Takeshi Yamamoto 1006 Kadoma Kadoma, Osaka Pref. Matsushita Electric Industrial Co., Ltd. Person Junichi Yugawa 1006 Kadoma, Kazuma, Kadoma, Osaka Prefecture Inside Matsushita Electric Industrial Co., Ltd. (72) Inventor Masami Tamura 1006 Kadoma, Kazuma, Kadoma, Osaka Pref. 1006 Oojidomashin Matsushita Electric Industrial Co., Ltd. (72) Inventor ▲ Yoshi ▼ Shigehiro 1006 Oojidoma Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. 69-7 F term (reference) 2F105 AA02 AA08 BB02 BB03 BB13 CC01 CC04 CD02 CD06 CD11 CD13

Claims (23)

[Claims] A first tuning fork portion comprising a base provided in an XY plane, at least a pair of tuning fork pieces extending from the base in a direction opposite to the Y-axis direction in the XY plane; Between a second tuning fork portion comprising at least a pair of tuning fork pieces extending in the Y-axis direction from the base so as to face the tuning fork portion of the first tuning fork portion, and a pair of tuning fork pieces forming the first tuning fork portion. And a pair of tuning fork pieces forming at least one bending vibration piece extending from the base in the direction opposite to the Y-axis direction, the first bending vibration section comprising the at least one bending vibration piece. A second bending vibration part comprising at least one bending vibration piece extending in the Y-axis direction from the base so as to be opposed to the first bending vibration part; The tuning fork piece constituting the second tuning fork portion is moved in the X-axis direction or X direction.
A driving means provided on the tuning fork for bending vibration in a direction opposite to the axial direction, and a Coriolis force acting in the Y-axis direction or in the direction opposite to the Y-axis direction when an angular velocity around the Z-axis is applied. The bending vibration piece for detecting a deformation amount of the bending vibration piece that bends and deforms in the X-axis direction or a direction opposite to the X-axis direction so as to keep a balance with the bending deformation of the tuning fork piece that changes according to the size. An angular velocity sensor comprising: a detection unit provided in 2. The X-axis direction or the direction opposite to the X-axis direction from each tip of a pair of tuning fork pieces forming the first and second tuning fork portions, and 1st, 2nd
A first additional mass portion is formed so as to extend in opposite directions to each other and to extend in the same direction on the same side with respect to the tuning fork pieces on both sides of each symmetry axis of the tuning fork portion. ,
One bending vibrating piece constituting each of the first and second bending vibrating portions is on the axis of symmetry of the tuning fork portion, and extends from the tip of each bending vibrating piece in the X-axis direction and the direction opposite to the X-axis direction. The angular velocity sensor according to claim 1, wherein the second additional mass portion is formed so as to protrude. 3. The angular velocity sensor according to claim 1, wherein the resonance frequencies of the first and second tuning fork portions and the resonance frequencies of the first and second bending vibration portions are close to each other. 4. A processing circuit for performing differential detection processing of each detection signal detected by the detection means provided in the first and second bending vibrating portions is connected to the detection means. 2. The angular velocity sensor according to 1. 5. A base provided in an XY plane, first and second bases.
The angular velocity sensor according to claim 1, wherein the tuning fork portion and the first and second bending vibration portions are integrally formed of a piezoelectric material. 6. A base provided in an XY plane, a first and a second
The angular velocity sensor according to claim 2, wherein the tuning fork portion, the first and second bending vibration portions, and the first and second additional mass portions are integrally formed of a piezoelectric material. 7. A base provided in an XY plane, a first and a second
The tuning fork portion and the first and second bending vibration portions are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and at least the first and second tuning fork portions and the first and second bending fork portions. 2. The angular velocity sensor according to claim 1, wherein a layer made of a piezoelectric material is provided on the XY plane of the bending vibration part. 8. A base provided in an XY plane, first and second bases.
The tuning fork portion, the first and second bending vibrating portions, and the first and second additional mass portions are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and at least the first and second bending mass portions. The angular velocity sensor according to claim 2, wherein a layer made of a piezoelectric material is provided on the XY plane of the tuning fork portion and the first and second bending vibration portions. 9. A base provided in an XY plane, a vibrating piece extending in a direction opposite to the Y-axis direction from the base in the XY plane, and an X-axis direction or an X-axis direction from a tip of the vibrating piece. An additional mass portion formed so as to extend in at least one of the directions opposite to the above, and the vibration for bending and vibrating the vibrating piece in the X-axis direction or the direction opposite to the X-axis direction. Driving means provided on the piece, and an X-axis direction of the vibrating piece that changes according to the magnitude of Coriolis force acting in the Y-axis direction or in the direction opposite to the Y-axis direction when an angular velocity about the Z-axis is applied Alternatively, an angular velocity sensor provided with a detecting means provided on the vibrating reed and also serving as the driving means for detecting an increase or decrease in the amplitude of the bending vibration in a direction opposite to the X-axis direction. 10. The angular velocity sensor according to claim 9, wherein the base, the resonator element, and the additional mass provided in the XY plane are integrally formed of a piezoelectric material. 11. A base, a resonator element and an additional mass part provided in the XY plane are formed of a constant elastic metal material, an oxide material or a high elastic polymer material, and at least on the XY plane of the resonator element. 10. A layer comprising a piezoelectric material is provided.
2. The angular velocity sensor according to 1. 12. A vibrating reed extending in the Y-axis direction, and an additional mass portion extending from either end of the vibrating reed in either the X-axis direction or the opposite direction to the X-axis direction or in both directions. And first and second support points provided on one of the XY planes of the vibrating piece to support the vibrating piece symmetrically on the Y axis, and provided on the other XY plane of the vibrating piece. Third and fourth support points, and first and third supports extending in the Z-axis direction and in a direction opposite to the Z-axis direction so as to be on the same straight line from the first and third support points, respectively. Parts, second and fourth support parts extending in the Z-axis direction and directions opposite to the Z-axis direction so as to be on the same straight line from the second and fourth support points, and the vibrating element. The first, second, third, and fourth support points are used as nodes of vibration to bend and vibrate in the primary mode in the XY plane. A driving means provided on the vibrating reed; and an X of the vibrating reed that changes according to the magnitude of Coriolis force acting in the Y-axis direction or in the direction opposite to the Y-axis direction when an angular velocity about the Z-axis is applied. An angular velocity sensor comprising: a detecting unit provided on the vibrating reed and also serving as the driving unit for detecting an increase or decrease in amplitude of bending vibration in a direction opposite to the axial direction or the X-axis direction. 13. The angular velocity sensor according to claim 12, wherein the vibrating reed and the additional mass portion are integrally formed of a piezoelectric material. 14. The vibrating reed and the additional mass portion are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and a layer made of a piezoelectric material is provided on at least the XY plane of the vibrating reed. An angular velocity sensor according to claim 12. 15. A base provided in the XY plane, a pair of tuning fork pieces extending from the base in the XY plane, and an X-axis direction or a direction opposite to the X-axis direction from each tip of the pair of tuning fork pieces. An additional mass portion formed so as to extend in one of the directions, and the pair of tuning forks for bending and vibrating the pair of tuning fork pieces in the X-axis direction or a direction opposite to the X-axis direction. A driving means provided on one of the tuning fork pieces, and an X of the pair of tuning fork pieces, which changes according to the magnitude of Coriolis force acting in the Y axis direction or in the direction opposite to the Y axis direction when an angular velocity around the Z axis is applied. An angular velocity sensor comprising: a detecting means provided on the pair of tuning fork pieces and also serving as the driving means for detecting an increase or decrease in amplitude of bending vibration in a direction opposite to the axial direction or the X-axis direction. 16. The angular velocity sensor according to claim 15, wherein the base, the pair of tuning forks, and the additional mass provided in the XY plane are integrally formed of a piezoelectric material. 17. A base, a pair of tuning fork pieces and an additional mass part provided in an XY plane are formed of a constant elastic metal material, an oxide material or a highly elastic polymer material, and at least the XY of the pair of tuning fork pieces. The angular velocity sensor according to claim 15, wherein a layer made of a piezoelectric material is provided on the surface. 18. A base provided in the XY plane, at least one pair of tuning fork pieces extending in the Y-axis direction from the base in the XY plane, and X centered on a symmetry axis of the pair of tuning fork pieces. Both the tuning fork piece on the axial direction side and the tuning fork piece on the side opposite to the X axis direction are in either one of the X axis direction or the direction opposite to the X axis direction from each tip and are the same. And at least one flexural vibrating reed between the pair of tuning fork pieces and extending from the base in the Y-axis direction, on the side of the additional mass part formed to extend in the same direction. A driving means provided on the tuning fork to bend and vibrate the tuning fork in the X-axis direction or the direction opposite to the X-axis direction; and when an angular velocity about the Z-axis is applied, According to the magnitude of Coriolis force acting in the direction opposite to the axial direction A detection device provided on the bending vibration piece for detecting a deformation amount of the bending vibration piece that bends and deforms in the X-axis direction or in a direction opposite to the X-axis direction so as to keep balance with the changing bending deformation of the tuning fork piece; Angular velocity sensor comprising: 19. A base, a tuning fork piece provided in an XY plane,
19. The angular velocity sensor according to claim 18, wherein the additional mass portion and the bending vibration piece are formed integrally from a piezoelectric material. 20. A base provided in an XY plane, a tuning fork,
The additional mass portion and the bending vibration piece are formed of a constant elastic metal material, an oxide material, or a high elastic polymer material, and a layer made of a piezoelectric material is provided on at least the XY plane of the tuning fork piece and the bending vibration piece. An angular velocity sensor according to claim 18. 21. Two bases provided in an XY plane, a first support formed to connect the bases in the Y-axis direction in the XY plane, and the first support. Second and third support portions extending from the center of the portion in the X-axis direction and the direction opposite to the X-axis direction; and the Y-axis direction and the direction opposite to the Y-axis direction from the tip of the second support portion. A first and a second vibrating reed extending from the tip of the third support portion in a Y-axis direction and a direction opposite to the Y-axis direction; An additional mass portion formed to extend from each tip of the first, second, third, and fourth vibrating reeds in one of the X-axis direction and a direction opposite to the X-axis direction; The first and second vibrating bars are vibrated in the X-axis direction or in a direction opposite to the X-axis direction by a drive signal of positive or negative polarity, and Driving means provided on the first, second, third, and fourth vibrating pieces for simultaneously vibrating the vibrating piece in the opposite direction to the first and second vibrating pieces; and an angular velocity about the Z axis. Is applied, the X-axis direction or the X-axis direction of the first, second, third, and fourth vibrating pieces changes according to the magnitude of the Coriolis force acting in the Y-axis direction or the direction opposite to the Y-axis direction. A detecting means provided on the first, second, third, and fourth vibrating reeds for detecting the amount of increase or decrease in the amplitude of the bending vibration in the direction opposite to the axial direction; Angular velocity sensor. 22. A base provided in an XY plane, a first, a second, a third support, a first, a second, a third, a fourth vibrating reed and an additional mass part are integrally formed of a piezoelectric material. 22. The angular velocity sensor according to claim 21, wherein the angular velocity sensor is formed. 23. A base, a first, a second, a third support, a first, a second, a third, a fourth vibrating reed and an additional mass provided in an XY plane are made of a constant elastic metal material. 22. The piezoelectric device according to claim 21, wherein a layer made of a piezoelectric material is provided on at least the XY plane of the first, second, third, and fourth resonator elements. Angular velocity sensor.