JP2012112819A - Vibration gyro - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small-size vibration gyro eliminating lowering of sensitivity to angular velocity around the Z-axis and having reduced sensitivity in other axial directions.SOLUTION: This vibration gyro includes a detecting element 1 that is disposed in a space represented by three X, Y and Z axes that are orthogonal to each other and is formed with a Z-axial through-hole on a flat plate that is parallel to the XY plane. The detecting element 1 comprises: a plurality of bending arms 3a-3d having a longitudinal direction in the Y-axis direction; a plurality of connecting parts 4a-4d orthogonally connecting the bending arms; drive means for exciting bending vibration of the bending arms; and detecting means for detecting the bending vibration of the bending arms. A first vibrator for detecting an angular velocity around the Y axis and the Z axis, and a second vibrator for detecting the angular velocity around the X axis are disposed in both sides of a Y-axial center line of the flat plate to detect the angular velocities of three axes.

Description

  The present invention relates to a vibration gyro for detecting an angular velocity used in a camera shake correction system, a navigation system, an attitude control system, and the like.

  Since a piezoelectric element using a piezoelectric material having high electro-mechanical conversion efficiency can realize a small and highly sensitive sensor, various sensors using this are manufactured. In recent years, a film-like piezoelectric body having a thickness of several μm, that is, a technique for forming a piezoelectric thin film on a large-area substrate with good reproducibility and a technique for finely processing a substrate have been established and utilized. Vibrating gyros can be manufactured with high productivity. Furthermore, products that can detect angular velocities of a plurality of axes in one package have been put into practical use.

  Patent Document 1 proposes a gyro module that can detect a triaxial angular velocity in one package. FIG. 5 is a plan view of a conventional gyro module that performs three-axis angular velocity detection. As shown in FIG. 5, the conventional gyro module for detecting the three-axis angular velocity has three gyro element pieces: a first gyro element piece 102, a second gyro element piece 103, and a fourth gyro element piece 104. Yes. A fourth gyro element piece 104 is arranged at the upper left of the drawing, a first gyro element piece 102 is arranged at the upper right of the drawing, and a second gyro element piece 103 is arranged at the lower right of the drawing. Further, the second gyro element piece 103 has the same configuration as that of the first gyro element piece 102, but is rotated 90 degrees in the XY plane. Among these gyro element pieces, the first gyro element piece 102 and the second gyro element piece 103 have two detection axes, and the fourth gyro element piece 104 has one detection axis. The first gyro element piece 102, the second gyro element piece 103, and the fourth gyro element piece 104 are made of quartz crystal, and are taken from a Z-cut quartz crystal substrate cut out on an XY plane formed by the X axis and the Y axis of the quartz crystal. Is formed.

  The first gyro element piece 102 having two detection axes has a rectangular base portion 105, and the base portion 105 has a connecting arm extending in both directions parallel to the X axis from the center of each end parallel to the Y axis. 106 exists. From the vicinity of the distal end of the connecting arm 106, there is a driving arm 107 extending in both directions parallel to the Y axis. A rectangular weight 108 having a width in the X-axis direction wider than that of the drive arm 107 is integrally formed with the drive arm 107 at the tip of each drive arm 107. The base 105 has a detection arm 109 extending in both directions parallel to the Y axis from the center of each end parallel to the X axis. A rectangular weight 110 having a width in the X-axis direction wider than that of the detection arm 109 is integrally formed with the detection arm 109 at the tip of each detection arm 109. The drive arm 107 is provided with a drive electrode (not shown), and the detection arm 109 is provided with a detection electrode (not shown).

  When a drive signal is supplied to the drive electrode of the drive arm 107 of the first gyro element piece 102, the drive arm 107 bends and vibrates symmetrically with respect to a line parallel to the Y axis passing through the center of gravity of the base portion 105. When an angular velocity around the Z axis is applied during such driving vibration, a Coriolis force in the Y axis direction acts on the driving arm 107. Since the detection arm 109 bends and vibrates under the influence of the Coriolis force, a detection signal is obtained from the detection electrode of the detection arm 109. Further, when the driving arm 107 is performing driving vibration, if the angular velocity around the Y axis is applied, the detection arm 109 is torsionally vibrated. This torsional vibration is a vibration mode in which the bending vibration in the X direction and the bending vibration in the z direction of the detection arm 109 generated by the Coriolis force are combined. A detection signal is obtained from the detection electrode by this torsional vibration. That is, the first gyro element piece 102 detects angular velocities around the Z axis and the Y axis. The second gyro element piece 103 has the same configuration as the first gyro element piece, but is rotated 90 degrees in the XY plane.

  The fourth gyro element piece 104 having one detection axis has the same configuration as the first gyro element piece 102, but the width in the X-axis direction of the weight part 111 provided at the tip of the detection arm 109 is different and narrows. ing. The reason why the width is set narrow is to prevent torsional vibration of the detection arm 109 so that the angular velocity of the Y-axis rotation system is not detected. A drive electrode (not shown) is provided on the drive arm 107 of the fourth gyro element piece 104, and a detection electrode is provided on the detection arm 109 (not shown).

  When an electric signal is supplied to the drive electrode of the fourth gyro element piece 104, the drive arm 107 is bent and vibrated symmetrically. At this time, if an angular velocity around the Z axis is applied, Coriolis force in the Y axis direction acts on the drive arm 107. Since the detection arm 109 bends and vibrates under the influence of the Coriolis force, a detection signal can be obtained from the detection electrode.

  As shown in FIG. 5, each gyro element piece described above includes a fourth gyro element piece 104 at the upper left of the drawing, a first gyro element piece 102 at the upper right of the drawing, and a second gyro element piece 103 at the lower right of the drawing. . By mounting with an IC chip having an oscillation circuit or the like on the substrate in such an arrangement, a gyro module that performs three-axis angular velocity detection that can be configured by one package is obtained.

  Further, Patent Document 2 discloses a small inertial force in which the inertial force of a plurality of detection shafts can be detected by using an arm having a bent portion as a vibration gyro using a piezoelectric thin film, and the mounting area is reduced. Sensors have been proposed. FIG. 6 is a plan view of a detection element of a vibration gyro having a conventional bent portion. As shown in FIG. 6, a conventional vibrating gyroscope having a bent portion has a detection element 201 and a processing circuit for detecting angular velocity and acceleration. The detection element 201 is integrally formed using a silicon substrate as a material, and a Pt lower electrode, a PZT thin film, and an Au upper electrode are formed on a part of the surface thereof. The detection element 201 includes a base portion 209 that is also a support portion 208, a first arm 202 that is connected to the base portion 209 and is parallel to the Y axis, a second arm 204, and a weight portion 218. The first arm 202 is connected to the second arm 204 in the orthogonal direction, and the second arm 204 is bent at the bent portions 204a on both sides, and the weight portion 218 is attached to each of the bent end portions 204b. Are connected to each other and are configured as symmetrical vibrators with the first arm 202 interposed therebetween, and the vibrators are also arranged at symmetrical positions with respect to the center line of the base portion 209 in the X-axis direction.

  A drive electrode (not shown) is formed on the end 204b of the second arm 204, and when an angular velocity about the Z axis is applied to the end 204b in a state where a drive vibration that vibrates in the X-axis direction is applied. The Coriolis force generated in the weight portion 218 displaces the second arm 204 in the Y-axis direction. Similarly, when an angular velocity around the Y axis is applied, the Coriolis force generated in the weight portion 218 displaces the second arm 204 in the Z axis direction. The vibration gyro is performed by detecting the displacement generated by the drive of the vibration and the Coriolis force by the PZT thin film formed on the surface of the detection element 201 and the detection electrode (not shown). The function as is obtained.

JP 2010-117375 A International Publication No. 2007/086337

  In the invention described in Patent Document 1, as shown in FIG. 5, the second gyro element piece 103 is arranged to be rotated 90 degrees in the XY plane with respect to the first gyro element piece 102. In order to increase the amplitude by increasing the amplitude by decreasing the resonance frequency, it is necessary to increase the length of the drive arm and the detection arm not only in the X direction but also in the Y direction. Accordingly, there is a problem that it is difficult to reduce the size of the gyro module as a whole.

  In the invention described in Patent Document 2, as shown in FIG. 6, the second arm 204 detects vibrations in the Z-axis direction and the Y-axis direction due to the Coriolis force generated in the weight portion 218. The resonance frequency at which the end portion 204b of the second arm 204 vibrates in the X-axis direction needs to coincide with or approach the resonance frequency at which the second arm 204 vibrates in the Y-axis direction and the resonance frequency at which the second arm 204 vibrates in the Z-axis direction. . Therefore, when the end portion 204b of the second arm 204 is driven and vibrated in the X-axis direction, the second arm 204 also vibrates in the Y-axis direction. As a result, the weight portion 218 connected to the end portion 204b of the second arm 204 has a vibration speed not only in the X-axis direction but also in the Y-axis direction.

  When an angular velocity about the Z axis is added to these two vibration speeds, as described above, the Coriolis force generated at the vibration speed in the X axis direction of the weight portion 218 displaces the second arm 204 in the Y axis direction. At the same time, the Coriolis force generated at the vibration speed of the weight portion 218 in the Y-axis direction displaces the second arm 204 in the X-axis direction. Here, since the two generated Coriolis forces work in opposite directions when viewed as a whole of the second arm 204, the detection sensitivity of the angular velocity around the Z axis is lowered.

  Further, when the end portion 204b of the second arm 204 is displaced in the Z-axis direction, the connected second arm 204 is not only displaced in the Z-axis direction but is also displaced in the Y-axis direction. Accordingly, the second arm 204 is displaced in the Y-axis direction not only with respect to the angular velocity around the Z axis but also with respect to the angular velocity around the Y axis, and the angular velocity around the Y axis is taken as the angular velocity around the Z axis. It will be detected. That is, other axis sensitivity is produced. This other-axis sensitivity can be reduced by applying signal processing such as an addition / subtraction circuit to the outputs of the four second arms 204, but there are circuit elements such as resistors that determine the amplification factor of the signal processing circuit. Since there is variation, it is difficult to reduce the sensitivity of other axes to several percent or less by such signal processing.

  The present invention has been made in view of the above-described problems, and an object of the present invention is to provide a vibrating gyroscope that is small in size, has no decrease in sensitivity to angular velocity around the Z axis, and further has reduced sensitivity in other axes. It is in.

  According to the present invention, there is provided a vibrating gyroscope having a detection element that is arranged in a space represented by three axes X, Y, and Z orthogonal to each other and has a through hole in the Z-axis direction formed on a flat plate parallel to the XY plane. The detection element includes a plurality of bending arms having a longitudinal direction in the Y-axis direction, and a plurality of connecting portions connected at right angles to the bending arms, and driving means for exciting bending vibrations of the bending arms, Detecting means for detecting bending vibration of the bending arm, and detecting a first vibrator for detecting angular velocities around the Y axis and the Z axis on both sides of a center line in the Y axis direction of the flat plate and an angular velocity around the X axis. A vibration gyro characterized by disposing a second vibrator and detecting the angular velocity of the three axes is obtained. The present invention is characterized in that the longitudinal direction of the bending arm is configured to be parallel to the Y-axis direction.

  Further, according to the present invention, the first vibrator extends from the center of the first joint having a longitudinal direction in the X-axis direction through the center of the first vibrator. One end of the first bent arm and the second bent arm are connected to each other at right angles symmetrically with respect to the XZ plane passing through the center line, and the center of the second connecting portion is connected to the other end of the first bent arm. Are connected at right angles, and a third bent arm and a fourth bent arm are arranged symmetrically with respect to a YZ plane passing through the center line of the first bent arm, and the third bent arm and the fourth bent arm are arranged. One end of the bending arm and both ends of the second connecting portion in the X-axis direction are connected at a right angle, and the other end of the second bending arm is connected to the central portion of the third connecting portion at a right angle. A fifth bent arm and a sixth bent arm are arranged symmetrically with respect to the YZ plane passing through the center line of the second bent arm, One end of the bending arm, the sixth bending arm, and both ends of the third connecting portion in the X-axis direction are connected at right angles, and the second vibrator is centered on the second vibrator. One end of the seventh bent arm and the eighth bent arm symmetrically with respect to the XZ plane passing through the center line of the fourth connecting portion from the central portion of the fourth connecting portion having a longitudinal direction in the X-axis direction. Are connected at right angles, and the other end of the seventh bent arm is connected to the center of the fifth connecting portion at a right angle, and symmetrically with respect to the YZ plane passing through the center line of the seventh bent arm. 9 bent arms and 10th bent arms, one end of the ninth bent arm, the 10th bent arm and both ends of the fifth connecting portion in the X-axis direction are connected at right angles, The center of the sixth connecting portion is connected to the other end of the 8 bent arm at a right angle, and the center line of the 8 bent arm An eleventh bent arm and a twelfth bent arm are arranged symmetrically with respect to the passing YZ plane, and the eleventh bent arm, one end of the twelfth bent arm, and the sixth connecting portion in the X-axis direction are arranged. A vibrating gyroscope characterized in that both ends are connected at right angles is obtained.

  In the vibration gyro described above, the first vibrator is connected to the other end of the third bent arm and the fourth bent arm that is not connected to the second connecting portion. A pair of additional mass portions having a symmetrical shape with respect to the YZ plane passing through the center line of the arm and not connected to the third connecting portion of the fifth bent arm and the sixth bent arm A pair of additional mass portions having a symmetrical shape with respect to a YZ plane passing through the center line of the second bent arm at the end, and the second vibrator includes the ninth bent arm and the A pair of additional mass portions having a symmetrical shape with respect to a YZ plane passing through a center line of the seventh bending arm at the other end not connected to the fifth coupling portion of the ten bending arms, Eleventh bending arm and twelfth bending arm Sixth other end that is not connected to the connecting portion of the arm, may include a pair of additional mass portion having a symmetrical shape with respect to the YZ plane through the center line of the eighth bending arm.

  Further, in the above vibrating gyroscope, the detection element has a rectangular shape in which the outer shape of the surface parallel to the XY plane of the bending arm and the connecting portion is composed of sides in the X-axis direction and the Y-axis direction, The lengths of the sides of the first vibrator in the Y-axis direction of the second connecting portion and the third connecting portion are the lengths of the sides of the third to sixth bent arms in the X-axis direction. The length of the side of the second vibrator in the Y-axis direction of the fifth coupling portion and the sixth coupling portion is not less than 2 times and not more than 5 times the length. It may be not less than 2 times and not more than 5 times the length of the side in the X-axis direction of the bending arm to the twelfth bending arm.

  In the vibration gyro described above, the detection element includes a frame formed by a part of the flat plate outside the first vibrator and the second vibrator, and the first coupling portion and Both ends of the fourth connecting portion in the X-axis direction may be connected to the frame, and the frame may be supported and fixed.

  With the configuration described above, the present invention has the following effects. That is, the vibrating gyroscope of the present invention can detect the three-axis angular velocities of the X axis, the Y axis, and the Z axis. In addition, since all the longitudinal directions of the bending arms are parallel to the Y-axis, the resonance frequency depends on the dimensions in the Y-axis direction, so that the dimensions in the X-axis and Z-axis directions can be kept small, and the element area is small. But it can be designed with high sensitivity. Moreover, high sensitivity is achieved by adopting a drive vibration mode having a high Q value. Further, since the rigidity of the connecting portion is high and does not deform, the drive vibration direction can be limited to the X-axis direction or the Z-axis direction, the sensitivity of the other axis is small, and the sensitivity to the angular velocity around the Z axis does not decrease. Furthermore, since the frame can be supported and fixed, mounting is easy and mass productivity is high.

  That is, according to the present invention, it is possible to obtain a vibrating gyroscope that is small in size and has no decrease in sensitivity with respect to the angular velocity around the Z axis and further reduces the sensitivity in the other axis.

1 is a perspective view of a detection element according to an embodiment of a vibration gyro according to the present invention. Explanatory drawing of the structure of the 1st bending arm 3a. 2A is a plan view, and FIG. 2B is a cross-sectional view taken along line AA. Explanatory drawing of the structure of the 3rd bending arm 5a. 3A is a plan view, and FIG. 3B is a cross-sectional view taken along the line BB. Explanatory drawing of the structure of the 9th bending arm 5e. 4A is a plan view, and FIG. 4B is a cross-sectional view taken along the line CC. The top view of the gyro module which performs the conventional triaxial angular velocity detection. The top view of the detection element of the vibration gyro which has the conventional bending part.

  Hereinafter, embodiments of the present invention will be described in detail.

  FIG. 1 is a perspective view of a detection element according to an embodiment of a vibration gyro according to the present invention. As shown in FIG. 1, the vibration gyro according to the present embodiment forms a through-hole in the Z-axis direction on a flat plate parallel to the XY plane in a space represented by three axes X, Y, and Z orthogonal to each other. The vibration gyro is capable of detecting three angular velocities around the X axis, the Y axis, and the Z axis using the detection element 1 including the first vibrator and the second vibrator. The detection element 1 includes a plurality of bending arms having a longitudinal direction in the Y-axis direction, which will be described later, and a plurality of connecting portions that are connected to the bending arms at right angles, and driving means for exciting bending vibrations of the bending arms; A first vibrator and a second vibrator provided with a detecting means for detecting the bending vibration of the arm.

  The first vibrator located on the left side of FIG. 1 has a configuration described below. A first connecting portion 4e provided parallel to the X-axis direction through the center of the first vibrator, and an XZ plane passing from the central portion of the first connecting portion 4e to the central line of the first connecting portion 4e. Symmetrically, one end of the first bent arm 3a and the second bent arm 3b are connected at a right angle, and the other end of the first bent arm 3a is connected at the center of the second connecting portion 4a at a right angle, The third bent arm 5a and the fourth bent arm 5b are arranged symmetrically with respect to the YZ plane passing through the center line of the first bent arm 3a, and one ends of the third bent arm 5a and the fourth bent arm 5b. And both ends of the second connecting portion 4a in the X-axis direction are connected at right angles. Furthermore, the other end of the second bending arm 3b is connected to the central portion of the third connecting portion 4b at a right angle, and the fifth bending is symmetrical with respect to the YZ plane passing through the center line of the second bending arm 3b. The arm 5c and the sixth bending arm 5d are arranged, and one ends of the fifth bending arm 5c and the sixth bending arm 5d and both ends in the X-axis direction of the third connecting portion 4b are connected at right angles.

  The additional mass portion 6a and the additional mass portion 6b are connected to the other ends of the third bending arm 5a and the fourth bending arm 5b that are not connected to the second connecting portion 4a. The additional mass portion 6c and the additional mass portion 6d are connected to the other ends of the fifth bent arm 5c and the sixth bent arm 5d that are not connected to the third connecting portion 4b. The first vibrator has a substantially symmetric shape with respect to the XZ plane and the YZ plane passing through the center of the first connecting portion 4e.

  Further, the second vibrator located on the right side of FIG. 1 has a configuration described below. A fourth connecting portion 4f provided in parallel with the X-axis direction through the center of the second vibrator, and an XZ plane passing from the center of the fourth connecting portion 4f to the center line of the fourth connecting portion 4f. Symmetrically, one end of the seventh bending arm 3c and the eighth bending arm 3d is connected at a right angle, and the other end of the seventh bending arm 3c is connected at the center of the fifth connecting portion 4c at a right angle, The ninth bent arm 5e and the tenth bent arm 5f are arranged symmetrically with respect to the YZ plane passing through the center line of the seventh bent arm 3c, and one ends of the ninth bent arm 5e and the tenth bent arm 5f are arranged. And both ends of the fifth connecting portion 4c in the X-axis direction are connected at right angles. Further, the center of the sixth connecting portion 4d is connected to the other end of the eighth bent arm 3d at a right angle, and the eleventh bent symmetrically with respect to the YZ plane passing through the center line of the eighth bent arm 3d. The arm 5g and the twelfth bent arm 5h are arranged, and one end of the eleventh bent arm 5g and the twelfth bent arm 5h and both ends in the X-axis direction of the sixth connecting portion 4d are connected at right angles.

  An additional mass portion 6e and an additional mass portion 6f are connected to the other ends of the ninth bending arm 5e and the tenth bending arm 5f that are not connected to the fifth connecting portion 4c. The additional mass portion 6g and the additional mass portion 6h are connected to the other ends of the eleventh bent arm 5g and the twelfth bent arm 5h that are not connected to the sixth connecting portion 4d. The second vibrator has a substantially symmetric shape with respect to the XZ plane and the YZ plane passing through the center of the fourth connecting portion 4f.

  In addition, the outer shape of the bending arm of the vibrating gyroscope of the present embodiment and the XY plane parallel to the XY plane has a rectangular shape composed of sides in the X-axis direction and the Y-axis direction. The length of the sides in the Y-axis direction of the second connecting portion 4a and the third connecting portion 4b is relative to the length of the sides in the X-axis direction of the third bent arm 5a to the sixth bent arm 5d. The length of the sides of the second vibrator in the Y-axis direction of the fifth coupling portion 4c and the sixth coupling portion 4d is not less than 2 times and not more than 5 times. The length of the side of the bending arm 5h in the X-axis direction is not less than 2 times and not more than 5 times.

  Further, in the detection element 1 of the vibration gyro according to the present embodiment, a frame 2 is formed on the outer periphery, and the first coupling portion 4e of the first vibrator and the fourth coupling portion 4f of the second vibrator are the frames. 2 and the first vibrator and the second vibrator are connected via the frame 2.

  Here, in the detection element 1 of the vibration gyro according to the present embodiment, a lower electrode is formed on one main surface of a substrate that is a flat plate constituting the vibrator, a piezoelectric thin film is formed on the upper surface, and the upper surface is further formed. In addition, through holes are formed on a substrate on which a plurality of upper electrodes serving as drive means or detection means are formed, so that the first vibrator, the second vibrator, and the frame 2 are configured.

  The first vibrator includes first driving means (not shown) for bending and vibrating the third bending arm 5a to the sixth bending arm 5d in the X-axis direction, the first bending arm 3a and the second bending arm 5a. First detection means (not shown) for detecting bending vibration in the X-axis direction of the bending arm 3b and second detection means for detecting bending vibration in the Z-axis direction of the third bending arm 5a to the sixth bending arm 5d. Detection means (not shown). The first driving means and the second detecting means are formed on the third bent arm 5a, the fourth bent arm 5b, the fifth bent arm 5c, and the sixth bent arm 5d, and the first detecting means is The first bent arm 3a and the second bent arm 3b are formed.

  Similarly, the second vibrator includes second driving means (not shown) for bending and vibrating the ninth bending arm 5e to the twelfth bending arm 5h in the Z-axis direction, the seventh bending arm 3c, Third detection means (not shown) for detecting bending vibration in the X-axis direction of the eighth bending arm 3d is provided. The second driving means is formed on the ninth bending arm 5e, the tenth bending arm 5f, the eleventh bending arm 5g, and the twelfth bending arm 5h, and the third detection means is the seventh bending arm 3c and It is formed on the eighth bending arm 3d.

  2A and 2B are explanatory views of the structure of the first bending arm 3a. FIG. 2A is a plan view and FIG. 2B is a cross-sectional view taken along the line AA. The seventh bent arm 3c in FIG. 1 has the same structure, and the second arm 8b and the eighth bent arm 3d have the same structure except that they are symmetrical with respect to the X axis. The cross sections of the bending arm 3b, the seventh bending arm 3c, and the eighth bending arm 3d have the same configuration. As shown in FIGS. 1 and 2, the lower electrode 9 is formed on one main surface of the substrate 8, the piezoelectric thin film 10 is formed on the upper surface, and the detection electrode 13a and the detection electrode 13b are formed as upper electrodes on the upper surface. Is formed. The portions where the detection electrodes 13a and 13b of the first bent arm 3a and the second bent arm 3b are formed are the first detection means, and the detection electrodes of the seventh bent arm 3c and the eighth bent arm 3d. The portion where 13a and 13b are formed is the third detecting means. When the first bending arm 3a, the second bending arm 3b, the seventh bending arm 3c, and the eighth bending arm 3d are displaced in the X-axis direction, the piezoelectric thin film 10 in the vicinity of the detection electrodes 13a and 13b is opposite to each other. Directional distortion occurs. Due to this distortion, voltages having opposite phases are generated in the detection electrodes 13a and 13b. By detecting this voltage with a predetermined detection circuit, the displacement in the X-axis direction of the first bent arm 3a, the second bent arm 3b, the seventh bent arm 3c, and the eighth bent arm 3d can be detected.

  3A and 3B are explanatory views of the structure of the third bending arm 5a, in which FIG. 3A is a plan view and FIG. 3B is a cross-sectional view along the line BB. The cross sections of the fourth bending arm 5b, the fifth bending arm 5c, and the sixth bending arm 5d in FIG. 1 have the same configuration. As shown in FIGS. 1 and 3, a lower electrode 9 is formed on one main surface of a substrate 8, a piezoelectric thin film 10 is formed on the upper surface thereof, and a driving electrode 11a and a driving electrode 11b are formed as upper electrodes on the upper surface. The detection electrode 12 is formed. The portion where the drive electrodes 11a and 11b are formed is the first drive means, and the portion where the detection electrode 12 is formed is the second detection means. When drive signals having opposite phases are applied to the drive electrodes 11a and 11b, the piezoelectric thin films 10 in the vicinity of the drive electrodes 11a and 11b generate strains in opposite directions with respect to the Y-axis direction. Due to this strain, vibrations in the X-axis direction of the third bending arm 5a to the sixth bending arm 5d can be excited.

  Further, since the drive electrodes 11a and 11b can detect the displacement of the third bent arm 5a to the sixth bent arm 5d in the X-axis direction, the drive electrodes 11a and 11b or a part of the drive electrodes 11a and 11b can be detected as the drive electrodes. The self-excited oscillation circuit can be used as a monitor electrode.

  Further, when displacement in the Z-axis direction occurs, distortion occurs in the piezoelectric thin film 10 in the vicinity of the detection electrode 12. Due to this strain, a voltage corresponding to the strain is generated in the detection electrode 12. By detecting this voltage with a predetermined detection circuit, the displacement in the Z-axis direction of the third bending arm 5a to the sixth bending arm 5d can be detected. At this time, a voltage corresponding to the strain is also generated in the detection electrodes 13a and 13b formed on the first bent arm 3a and the second bent arm 3b shown in FIG. Since this voltage becomes a signal having the same phase at the detection electrodes 13a and 13b, it can be detected separately from the displacement in the X-axis direction by performing signal processing of subtraction and addition.

  Note that distortion is generated in the piezoelectric thin film 10 in the vicinity of the detection electrode 12 even when the third bending arm 5a to the sixth bending arm 5d are displaced in the X-axis direction. However, since this strain is distributed in the opposite direction with the center line dividing the width of the third bending arm 5a to the sixth bending arm 5d into two equal parts, almost no voltage is generated in the detection electrode 12.

  4A and 4B are explanatory views of the structure of the ninth bending arm 5e. FIG. 4A is a plan view and FIG. 4B is a cross-sectional view taken along the line CC. The cross sections of the tenth bending arm 5f, the eleventh bending arm 5g, and the twelfth bending arm 5h in FIG. 1 have the same configuration. As shown in FIGS. 1 and 4, a lower electrode 9 is formed on one main surface of a substrate 8, a piezoelectric thin film 10 is formed on the upper surface, and a drive electrode 14 is formed on the upper surface as an upper electrode. Yes. The portion where the drive electrode 14 is formed is the second drive means. When a drive signal is given to the drive electrode 14, the piezoelectric thin film 10 near the drive electrode 14 is distorted in the Y-axis direction. Due to this strain, vibrations in the Z-axis direction of the ninth bending arm 5e to the twelfth bending arm 5h can be excited.

  Further, since the drive electrode 14 can also detect the displacement of the ninth bending arm 5e to the twelfth bending arm 5h in the Z-axis direction, the drive electrode 14 or a part of the drive electrode 14 with respect to the drive electrode can be detected. It can also be used as a monitor electrode when configuring a self-excited oscillation circuit.

  Next, a method for detecting the angular velocity of the detection element 1 of the present invention will be described.

(First vibrator)
The vibration in which the pair of bending arms including the third bending arm 5a and the fourth bending arm 5b shown in FIG. 1 are displaced in the X-axis direction in opposite directions can provide very stable characteristics. The force generated by these displacements cancels out in the vicinity of the connecting portion between the second connecting portion 4a and the first bending arm 3a, and becomes a node point. Similarly, the vibration in which the pair of bending arms including the fifth bending arm 5c and the sixth bending arm 5d are displaced in the X-axis direction in opposite directions can have very stable characteristics. The stable characteristic in the present embodiment is to maintain a high Qm (mechanical resonance sharpness) for a desired vibration mode regardless of the influence of disturbance such as a fixed condition.

  Therefore, the vibrations in which the third bending arm 5a and the fifth bending arm 5c and the fourth bending arm 5b and the sixth bending arm 5d are opposite to each other and displaced in the X-axis direction also have very stable characteristics. It is done. Therefore, it is preferable to select this vibration in the X-axis direction as a drive vibration mode when detecting angular velocities around the Y-axis and the Z-axis. This driving vibration mode can be excited by the first driving means formed on the third bending arm 5a to the sixth bending arm 5d. However, it is desirable that the frequency of the drive signal input to the first drive means is a frequency near the resonance frequency of each drive vibration mode.

  Further, the additional mass portions 6a to 6d are connected to the tips of the third bending arm 5a to the sixth bending arm 5d, respectively, and this additional mass portion expands the operation of the bending arm and resonates. Has the function of increasing the displacement by lowering the frequency.

  The force generated by the displacement described above is canceled out near the connecting portion between the second connecting portion 4a and the first bent arm 3a, and between the third connecting portion 4b and the second bent arm 3b, and becomes a node point. . Therefore, the displacement amount of the first connecting portion 4e that connects the first bending arm 3a and the second bending arm 3b is relatively small, and support and fixation with little influence on each bending arm are possible.

  Further, the second connecting portion 4a and the third connecting portion 4b are formed with the intention of electrical connection and propagation of vibration, and are not intended for excitation or detection of vibration. Therefore, when the second connecting portion 4a and the third connecting portion 4b have sufficient rigidity with respect to the third bent arm 5a to the sixth bent arm 5d, the above-described driving vibration mode is excited. Even so, since the displacement generated in the second connecting portion 4a and the third connecting portion 4b is very small, the third bending arm 5a to the sixth bending arm 5d and the additional mass at the time of excitation in the driving vibration mode. The displacement of the portion 6a to the additional mass portion 6d is substantially limited in the X-axis direction. Thus, the structure which suppresses the displacement of the 2nd connection part 4a and the 3rd connection part 4b is obtained by designing as follows, for example. That is, the outer shapes of the third bending arm 5a to the sixth bending arm 5d and the planes parallel to the XY plane of the second connecting portion 4a and the third connecting portion 4b are the sides in the X-axis direction and the Y-axis direction. The length of the sides in the Y-axis direction of the second connecting portion 4a and the third connecting portion 4b is set to the length of the sides in the X-axis direction of the third bent arm 5a to the sixth bent arm 5d. It is obtained by making it twice or more with respect to the length. The lengths of the sides in the Y-axis direction of the second connecting portion 4a and the third connecting portion 4b are relative to the lengths of the sides in the X-axis direction of the third bent arm 5a to the sixth bent arm 5d. In the case of exceeding 5 times, further displacement suppression effect cannot be obtained, and since it is an adverse effect of downsizing, it is desirable to make it 5 times or less.

  When the angular velocity around the Y axis is applied in the state where the vibration in the X axis direction is excited as the driving vibration mode, the third bending arm 5a and the fifth bending arm 5c, the fourth bending arm 5b and the sixth bending arm 5c are applied. The bending arms 5d are displaced in the Z-axis direction in opposite directions by the generated Coriolis force. This displacement in the Z-axis direction can be detected by second detection means formed on the third bending arm 5a to the sixth bending arm 5d. Thereby, it can be made to function as a vibration gyro which detects the angular velocity around the Y axis.

  Similarly, when an angular velocity around the Z axis is applied in a state where the vibration in the X-axis direction is excited as a driving vibration mode, the third bending arm 5a, the fifth bending arm 5c, and the fourth bending arm 5b are applied. The sixth bending arm 5d receives forces in the Y-axis direction in opposite directions due to the generated Coriolis force. Accordingly, the third bending arm 5a to the sixth bending arm 5d are displaced in the Y-axis direction. However, since this force is a force acting in the longitudinal direction of the bending arm, there is almost no deformation. That is, since the third bending arm 5a to the sixth bending arm 5d have sufficient rigidity in the Y-axis direction as compared with the X-axis and Z-axis directions, the third bending arm is caused by this force. The signal generated in the first detection means formed on the 5a to 6th bending arms 5d is sufficiently negligible.

  The displacement of the third bending arm 5a to the sixth bending arm 5d in the Y-axis direction causes the second connecting portion 4a and the third connecting portion 4b to rotate by applying a moment about the Z axis. Accordingly, the first bent arm 3a and the second bent arm 3b connected to the second connecting portion 4a and the third connecting portion 4b are displaced in the X-axis direction in opposite directions. This displacement in the X-axis direction can be detected by first detection means formed on the first bent arm 3a and the second bent arm 3b. Thereby, it can be made to function as a vibration gyro which detects the angular velocity around the Z axis.

(Second vibrator)
The pair of bending arms including the ninth bending arm 5e and the eleventh bending arm 5g and the pair of bending arms including the tenth bending arm 5f and the twelfth bending arm 5h illustrated in FIG. Vibration that is displaced in the Z-axis direction provides relatively stable vibration characteristics. In detecting the angular velocity around the X-axis, it is preferable to select the vibration in the Z-axis direction as the drive vibration mode. The driving vibration mode displaced in the Z-axis direction can be excited by the second driving means formed on the ninth bending arm 5e to the twelfth bending arm 5h. However, it is desirable that the frequency of the drive signal input to the second drive means is a frequency near the resonance frequency of each drive vibration mode.

  Further, the additional mass portions 6e to 6h are connected to the tips of the ninth bending arm 5e to the twelfth bending arm 5h, respectively, and this additional mass portion expands the operation of the bending arm and resonates. Has the function of increasing the displacement by lowering the frequency.

  The force generated by the displacement described above causes the fifth connecting portion 4c and the sixth connecting portion 4d to rotate about the Y axis, but the fifth connecting portion 4c, the seventh bent arm 3c, and the sixth The vicinity of the connecting portion between the connecting portion 4d and the eighth bent arm 3d is a node point. Therefore, the amount of displacement of the fourth connecting portion 4f that connects the seventh bent arm 3c and the eighth bent arm 3d is relatively small, and support and fixation with little influence on each bent arm are possible.

  Further, the fifth connecting portion 4c and the sixth connecting portion 4d are formed for the purpose of electrical connection and propagation of vibration, and are not intended for excitation or detection of vibration. Accordingly, when the fifth connecting portion 4c and the sixth connecting portion 4d have sufficient rigidity with respect to the ninth bent arm 5e to the twelfth bent arm 5h, the above-described drive vibration mode is excited. Even so, since the displacement generated in the fifth connecting portion 4c and the sixth connecting portion 4d is very small, the ninth bending arm 5e to the twelfth bending arm 5h and the additional mass at the time of excitation in the drive vibration mode. The displacement of the portion 6e to the additional mass portion 6h is substantially limited in the Z-axis direction. Thus, the structure which suppresses the displacement of the 5th connection part 4c and the 6th connection part 4d is obtained by designing as follows, for example. That is, the outer shapes of the ninth bending arm 5e to the twelfth bending arm 5h and the planes parallel to the XY plane of the fifth connecting portion 4c and the sixth connecting portion 4d are the sides in the X-axis direction and the Y-axis direction. The length of the sides in the Y-axis direction of the fifth connecting portion 4c and the sixth connecting portion 4d is set to the length of the sides in the X-axis direction of the ninth bent arm 5e to the twelfth bent arm 5h. It is obtained by making it twice or more with respect to the length. The length of the sides in the Y-axis direction of the fifth connecting portion 4c and the sixth connecting portion 4d is relative to the length of the sides in the X-axis direction of the ninth bent arm 5e to the twelfth bent arm 5h. In the case of exceeding 5 times, further displacement suppression effect cannot be obtained, and since it is an adverse effect of downsizing, it is desirable to make it 5 times or less.

  In the state where the vibration in the Z-axis direction is excited as the driving vibration mode, when the angular velocity around the X-axis is applied, the ninth bending arm 5e and the eleventh bending arm 5g, the tenth bending arm 5f and the twelfth The bending arm 5h receives forces in the Y-axis direction in opposite directions by the generated Coriolis force. Accordingly, the ninth bending arm 5e to the twelfth bending arm 5h are displaced in the Y-axis direction. However, since this force is a force acting in the longitudinal direction of the bending arm, there is almost no deformation. That is, the ninth bending arm 5e to the twelfth bending arm 5h have sufficient rigidity with respect to the Y-axis direction as compared with the X-axis and Z-axis directions. Signals generated in the second driving means formed on the 5e to 12th bending arms 5h are sufficiently negligible.

  The displacement of the ninth bending arm 5e to the twelfth bending arm 5h in the Y-axis direction causes the fifth connecting portion 4c and the sixth connecting portion 4d to rotate by applying a moment about the Z axis. Accordingly, the seventh bent arm 3c and the eighth bent arm 3d connected to the fifth connecting portion 4c and the sixth connecting portion 4d are displaced in the X-axis direction in opposite directions. This displacement in the X-axis direction can be detected by third detection means formed on the seventh bent arm 3c and the eighth bent arm 3d. As a result, it can function as a vibration gyro that detects an angular velocity around the X axis.

  As described above, the vibration gyro of the present invention can be expected to have a high Q value vibration by obtaining a relatively stable drive mode, and can be designed to have a low resonance frequency by the pair of additional mass portions. As described above, the present invention can increase the displacement by a high Q value and a low frequency design, and is suitable for a highly sensitive vibration gyro. Further, all the longitudinal directions of the bending arms were made parallel to the Y-axis direction. All the resonance frequencies of the vibration modes required as a vibration gyro greatly depend on the length of the arm in the Y-axis direction. Accordingly, when the frequency is lowered for higher sensitivity, it is only necessary to lengthen the element only in the Y-axis direction, so that a highly sensitive vibration gyro with a smaller element area and a low resonance frequency can be obtained. Furthermore, by limiting the drive vibration mode for Y-axis and Z-axis detection to vibration in the X-axis direction, it is possible to obtain a vibration gyro having no other-axis sensitivity and efficient detection of angular velocity around the Z-axis.

  Further, by combining the plurality of bending arms of the present invention and the detection vibration mode selected in the present invention, an error output with respect to acceleration in translational motion can be reduced. Normally, the detection output of the vibration gyro is performed by signal processing by synchronous detection using the drive signal or the like as a reference signal, so that signal components other than the frequency of the drive vibration mode are removed, but with one element such as a cantilever beam. In the configuration of the vibration gyro, it is difficult to separate a detection signal for acceleration and a detection signal for angular velocity, and an error output due to acceleration may not be negligible.

  In the vibration gyro according to the present invention, the detection vibration mode for detecting the angular velocity around the X axis is such that the seventh bending arm 3c and the eighth bending arm 3d of the second vibrator vibrate in the X axis direction in opposite directions. . Further, the detection vibration mode for detecting the angular velocity around the Y axis is such that the third bending arm 5a and the fifth bending arm 5c, and the fourth bending arm 5b and the sixth bending arm 5d are opposite to each other in the Z axis. Vibrates in the direction. Further, in the detection vibration mode for detecting the angular velocity around the Z axis, the first bending arm 3a and the second bending arm 3b vibrate in the X axis direction in opposite directions.

  As described above, the vibration modes detected by the vibration gyro of the present invention employ vibrations that are opposite to each other, and have a differential detection configuration when detecting angular velocity. Therefore, when acceleration in the X-axis, Y-axis, and Z-axis directions is applied, the detection vibration mode of the present invention is not excited, and the influence of the acceleration on the detection signal is small, and error output is reduced. Can be expected.

  According to the present invention, a vibration gyro capable of detecting the three-axis angular velocities of the X axis, the Y axis, and the Z axis is obtained. The detection element 1 in the vibration gyro according to the present invention is manufactured by simultaneous processing using a high-precision photolithography technique. Therefore, the orthogonality of the three detection axes is very good. Compared to a manufacturing method in which a plurality of elements are individually processed and assembled, the sensitivity of other axes can be reduced.

  Furthermore, according to the present invention, the frame 2 can be formed on the outer peripheral portion of the detection element 1, and the first connecting portion 4e and the fourth connecting portion 4f can be connected. As described above, the drive vibration mode of the vibration gyro according to the present invention is a vibration mode having relatively good symmetry, and the displacement at the first connecting portion 4e and the fourth connecting portion 4f is small, and is almost the node point. Can be considered. That is, the first connecting part 4e and the fourth connecting part 4f can be easily supported and fixed without impairing the vibration characteristics of the drive vibration mode. Therefore, the first connecting portion 4e and the fourth connecting portion 4f can be easily connected to the frame 2. It is easy to form electrode pads necessary for signal input / output on the frame 2 formed in the periphery, and it is also easy to mount the frame 2 on another mounting board.

  Next, specific examples of the vibrating gyroscope of the present invention will be described.

In this example, the vibrating gyroscope shown in FIG. 1 was produced. As shown in FIG. 1, the detection element 1 uses a 50 μm thick silicon substrate as a substrate 8, a lower electrode 9 is formed on the main surface, and a PZT thin film 2 μm thick as a piezoelectric thin film 10 on the upper surface. Further, an upper electrode was formed on the upper surface, and a through hole was formed by dry etching. The lower electrode 9 includes a silicon dioxide (SiO ₂ ) film having a thickness of 1 μm formed by oxidizing the surface of a silicon substrate, a titanium film having a thickness of 35 nm formed by sputtering, and a top surface thereof. And a platinum film having a thickness of 200 nm formed by sputtering. The upper electrode corresponds to the drive electrodes 11a, 11b, and 14, and the detection electrodes 12, 13a, and 13b. A 35 nm-thick chromium film formed by sputtering on the upper surface of the PZT thin film, and formed by sputtering on the upper surface. And a gold film having a thickness of 300 nm. Here, when the wiring electrode is formed on the PZT thin film, an insulating layer having a low dielectric constant may be formed on the PZT thin film and the wiring electrode may be formed thereon in order to reduce the capacitance.

  The second connecting portion 4a, the third connecting portion 4b, the fifth connecting portion 4c, and the sixth connecting portion 4d have a side length in the Y-axis direction of about 100 μm, and the third bent arms 5a to 6 The lengths of the sides in the X-axis direction of the bending arms 5d and the ninth bending arm 5e to the twelfth bending arm 5h were about 50 μm. That is, the lengths of the sides in the Y-axis direction of the second connecting portion 4a, the third connecting portion 4b, the fifth connecting portion 4c, and the sixth connecting portion 4d are the third bending arm 5a to the sixth bending arm 5a. The bending arm 5d and the ninth bending arm 5e to the twelfth bending arm 5h are twice the length of the side in the X-axis direction.

  The second connecting portion 4a, the third connecting portion 4b, the fifth connecting portion 4c, and the sixth connecting portion 4d have side lengths in the X-axis direction of about 500 μm, and the third bent arms 5a to 6 The bending arm 5d and the ninth bending arm 5e to the twelfth bending arm 5h have a length in the Y-axis direction of about 500 μm. The additional mass portion 6a to the additional mass portion 6h have a rectangular shape with a side of about 400 μm.

  In this configuration, when the displacement distribution of the vibrator is analyzed by the finite element method analysis, the maximum displacement amount of the second connecting portion 4a and the third connecting portion 4b is the third bending arm 5a to the sixth bending arm. It was about 1% with respect to the maximum displacement amount of 5d, and the displacement was very small. Accordingly, the lengths of the sides in the Y-axis direction of the second connecting portion 4a and the third connecting portion 4b are set to the lengths of the sides in the X-axis direction of the third bent arm 5a to the sixth bent arm 5d. The displacement suppression effect by making it 2 times or more was confirmed. Similar results were obtained for the displacement of the fifth connecting portion 4c and the sixth connecting portion 4d and the displacement of the ninth bending arm 5e to the twelfth bending arm 5h.

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments and examples, and the present invention can be applied even if there is a design change without departing from the gist of the present invention. include. That is, it goes without saying that the present invention also includes various variations and modifications that would be obvious to those skilled in the art. For example, in the vibrating gyroscope according to the above-described embodiment, a silicon substrate having a piezoelectric thin film such as a PZT thin film has been exemplified. The shape, number and arrangement of drive electrodes and detection electrodes in the drive means and detection means, and the shape of each arm and each connecting part can be designed according to the purpose and application. Yes, and not limited to those illustrated. For the method of making the connecting part difficult to be deformed by driving vibration, the rigidity of the connecting part is made different from the shape of the bent arm or by using a shape other than a rectangle, or the resonance frequency is driven and driven. It is possible to use various means such as moving away from the above-mentioned frequency, and forming a film having increased rigidity on the film.

1,201 detection element 2 frame 3a first bent arm 3b second bent arm 3c seventh bent arm 3d eighth bent arm 4a second connecting portion 4b third connecting portion 4c fifth connecting portion 4d 6th connecting portion 4e 1st connecting portion 4f 4th connecting portion 5a 3rd bent arm 5b 4th bent arm 5c 5th bent arm 5d 6th bent arm 5e 9th bent arm 5f 10th Bending arm 5g eleventh bending arm 5h twelfth bending arm 6a, 6b, 6c, 6d, 6e, 6f, 6g, 6h additional mass 8 substrate 9 lower electrode 10 piezoelectric thin film 11a, 11b, 14 driving electrode 12, 13a, 13b Detection electrode 102 First gyro element piece 103 Second gyro element piece 104 Fourth gyro element piece 105, 209 Base 106 Connecting arm 107 Driving arm 108, 110, 11 , 218 weight portion 109 detects arm 202 first arm 204 and the second arm 204a bent portion 204b end 208 support unit

Claims (5)

  A vibrating gyroscope having a detection element arranged in a space represented by three axes X, Y, and Z orthogonal to each other and having a through-hole in the Z-axis direction formed on a flat plate parallel to the XY plane, , A plurality of bending arms having a longitudinal direction in the Y-axis direction, and a plurality of connecting portions connected at right angles to the bending arms, driving means for exciting bending vibrations of the bending arms, and bending vibrations of the bending arms. A first vibrator for detecting angular velocities around the Y axis and the Z axis on both sides of a center line in the Y axis direction of the flat plate, and a second vibrator for detecting the angular velocity around the X axis. And an angular velocity of the three axes is detected.   The first vibrator extends from a central portion of the first connecting portion having a longitudinal direction in the X-axis direction through the center of the first vibrator to an XZ plane passing through the central line of the first connecting portion. Symmetrically, one end of the first bent arm and the second bent arm are connected at a right angle, and the other end of the first bent arm is connected at the center of the second connecting portion at a right angle, A third bent arm and a fourth bent arm are arranged symmetrically with respect to the YZ plane passing through the center line of one bent arm, and the third bent arm, one end of the fourth bent arm, and the second bent arm. Both ends of the connecting portion in the X-axis direction are connected at right angles, the center portion of the third connecting portion is connected at right angles to the other end of the second bent arm, and the center line of the second bent arm is connected A fifth bending arm and a sixth bending arm are arranged symmetrically with respect to the passing YZ plane, and the fifth bending arm and the sixth bending arm are arranged. One end of the bending arm and both ends of the third connecting portion in the X-axis direction are connected at right angles, and the second vibrator passes through the center of the second vibrator and is longitudinal in the X-axis direction. From the central part of the fourth connecting part having the above, the ends of the seventh bent arm and the eighth bent arm are connected at right angles to the XZ plane passing through the center line of the fourth connecting part, The other end of the seventh bending arm is connected to the center of the fifth connecting portion at a right angle, and the ninth bending arm and the tenth are symmetrical with respect to the YZ plane passing through the center line of the seventh bending arm. Bending arms, one end of the ninth bending arm, the tenth bending arm, and both ends of the fifth connecting portion in the X-axis direction are connected at right angles, and the other end of the eighth bending arm Is connected to the center of the sixth connecting portion at a right angle with respect to the YZ plane passing through the center line of the eighth bending arm. The eleventh bending arm and the twelfth bending arm are arranged, and one end of the eleventh bending arm, the twelfth bending arm, and both ends in the X-axis direction of the sixth connecting portion are connected at right angles. The vibrating gyroscope according to claim 1, wherein the vibrating gyroscope is configured as follows.   The first vibrator has a YZ plane that passes through the center line of the first bent arm at the other end of the third bent arm and the fourth bent arm that is not connected to the second connecting portion. A pair of additional mass portions having a symmetric shape with respect to the second bent portion at the other end not connected to the third connecting portion of the fifth bent arm and the sixth bent arm. A pair of additional mass portions having a symmetrical shape with respect to a YZ plane passing through the center line of the arm, and the second vibrator includes the fifth bending arm and the fifth bending arm. A pair of additional mass portions having a symmetric shape with respect to a YZ plane passing through the center line of the seventh bent arm at the other end not connected to the connecting portion of the eleventh bent arm and the twelfth portion. Not connected to the sixth connecting part of the bending arm 3. The vibrating gyroscope according to claim 1, further comprising a pair of additional mass portions having a symmetrical shape with respect to a YZ plane passing through a center line of the eighth bent arm at the other end. .   The outer shapes of the surfaces parallel to the XY plane of the bending arm and the connecting portion both have a rectangular shape composed of sides in the X-axis direction and the Y-axis direction, and the second connecting portion of the first vibrator The length of the side in the Y-axis direction of the third connecting portion is not less than 2 times and not more than 5 times the length of the side in the X-axis direction of the third to sixth bent arms. The lengths of the sides in the Y-axis direction of the fifth connecting portion and the sixth connecting portion of the second vibrator are in the X-axis direction of the ninth to twelfth bent arms. The vibrating gyroscope according to any one of claims 1 to 3, wherein the length is 2 to 5 times the length of the side.   The detection element includes a frame formed by a part of the flat plate outside the first vibrator and the second vibrator, and the X of the first coupling portion and the fourth coupling portion. 5. The vibrating gyroscope according to claim 1, wherein both ends in the axial direction are connected to the frame, and the frame is supported and fixed.

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