JP4848873B2 - Gyro vibrating piece - Google Patents

Description

  The present invention relates to a gyro vibrating piece used in a gyro sensor or the like that detects a rotational angular velocity.

In recent years, for example, a gyro sensor using a gyro vibrating piece such as a double T-type gyro vibrating piece has been expanded in use such as a portable device or an in-vehicle device. As a result, the temperature environment to be used varies widely, and for example, it is required to operate stably in a wide temperature range of −40 ° C. to + 85 ° C. In addition, downsizing is also required.
Such a gyro vibrating piece has a high ambient temperature even when the resonance frequency fd (Hz) (hereinafter referred to as “driving vibration frequency fd”) of the bending vibrating piece as the driving unit is adjusted to a constant value at room temperature. When the temperature changes to a low temperature, a so-called temperature drift such as a change in resonance frequency or a change in characteristics occurs. It is known that the occurrence of this temperature drift is influenced by the vibration in the out-of-plane bending vibration mode. In order to suppress this temperature drift, for example, Patent Document 1 discloses a driving vibration frequency fd (Hz) of a bending vibration piece and a resonance frequency fs (Hz) of an out-of-plane bending vibration mode (hereinafter referred to as “out-of-plane bending mode vibration frequency”. It is proposed that fs + 4500 ≧ fd ≧ fs + 1500 be related to fs ”.

JP 2004-101278 A

  However, the relationship between the driving vibration frequency fd of the bending vibration piece and the out-of-plane bending mode vibration frequency fs in the above-described conventional gyro vibrating piece is effective for the temperature drift of the large gyro vibrating piece. A sufficient effect was not found in the gyro vibrating piece. For example, a gyro vibrating piece of about 4 mm square has a sufficient effect, but a gyro vibrating piece of about 2 mm square has no effect of improving temperature drift. Thus, even if the relationship (fs + 4500 ≧ fd ≧ fs + 1500) shown in the prior art is applied to a small gyro vibrating piece of about 2 mm square, the vibration in the out-of-plane bending mode affects the driving vibration, There was a problem that temperature drift occurred.

  The present invention has been made in view of the above problems, and an object of the present invention is to prevent the influence of the vibration in the out-of-plane bending mode on the driving vibration and suppress the occurrence of temperature drift. The object is to provide a small gyro vibrating piece.

In order to solve such a problem, the present inventors have developed a harmonic component (hereinafter referred to as “harmonic component”) present in a frequency region about three times the drive vibration frequency fd as the gyro vibrating piece 10 is downsized. And the out-of-plane bending mode vibration frequency fs are easily approached, and the present invention has been completed.
The gyro vibrating piece according to the present invention is provided through a base and a support beam extending from the base, and has a driving unit having a predetermined driving vibration frequency fd, and extends from the base in the same plane as the driving unit. A gyro vibrating piece having a detection unit that detects detection vibration caused by Coriolis force accompanying rotation of the driving unit, wherein the gyro vibrating piece includes out-of-plane bending primary mode vibration and out-of-plane bending secondary It has mode vibration, and the out-of-plane bending primary mode vibration frequency fs1 is either fd × 2.2 ≦ fs1 ≦ fd × 2.8 or fd × 3.2 ≦ fs1 ≦ fd × 3.8. It is characterized by being formed.

  According to the gyro vibrating piece of the present invention, by setting the out-of-plane bending primary mode vibration frequency fs1 within this frequency region, the vibration frequency of the harmonic component in the vicinity of three times the drive vibration frequency fd where interference easily occurs can be obtained. A gyro vibrating piece that is separated from the out-of-plane bending primary mode vibration frequency fs can be formed. Thereby, it is possible to prevent interference between the vibration of the harmonic component of the drive vibration frequency fd and the vibration of the out-of-plane bending primary mode vibration frequency fs1. Accordingly, it is possible to provide a gyro vibrating piece capable of preventing the influence of the out-of-plane bending vibration mode vibration including the out-of-plane bending primary mode vibration on the driving vibration and suppressing the occurrence of temperature drift.

  Further, the out-of-plane bending secondary mode vibration frequency fs2 is formed such that either fd × 2.2 <fs2 ≦ fd × 2.8 or fd × 3.2 ≦ fs2 ≦ fd × 3.8. It is desirable that

  The out-of-plane bending primary mode vibration frequency fs1 is fd × 2.2 ≦ fs1 ≦ fd × 2.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 3.2 ≦ fs2 ≦ fd ×. It may be 3.8.

  The out-of-plane bending primary mode vibration frequency fs1 is fd × 2.2 ≦ fs1 ≦ fd × 2.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 2.2 <fs2 ≦ fd ×. It may be 2.8.

  The out-of-plane bending primary mode vibration frequency fs1 is fd × 3.2 ≦ fs1 ≦ fd × 3.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 3.2 ≦ fs2 ≦ fd ×. It may be 3.8.

  In this way, in addition to the out-of-plane bending primary mode vibration frequency fs1, the vibration frequency of the out-of-plane bending secondary mode vibration frequency fs2 is also separated from the vibration frequency of the harmonic component of the driving vibration frequency fd. In addition, it is possible to prevent interference between the vibrations and further suppress the temperature drift.

  The best mode of the gyro vibrating piece according to the present invention will be described below with reference to the drawings.

  First, the configuration of the gyro vibrating piece according to the present invention will be described with reference to FIG. FIG. 1 is a plan view schematically showing a schematic structure of the gyro vibrating piece.

  In this description, a so-called double T (tee) type gyro vibrating piece will be described as an example of the gyro vibrating piece. A gyro vibrating piece 10 shown in FIG. 1 is formed from a quartz substrate as an example of a piezoelectric substrate. The crystal forming this quartz substrate has an X axis called an electric axis, a Y axis called a mechanical axis, and a Z axis called an optical axis. The gyro vibrating piece 10 is formed in the XY plane of a Z-cut quartz substrate cut out in the plane direction of the X-axis and Y-axis of the quartz. The gyro vibrating piece 10 is formed of a quartz substrate having a predetermined thickness. The planar shape of the gyro vibrating piece 10 is developed on the XY plane in accordance with the crystal axis of the crystal, and has a shape that is 180 ° symmetrical with respect to the center point G. The center point G is the position of the center of gravity of the gyro vibrating piece 10. Here, the above-mentioned “point symmetry” and “center of gravity” are not geometrically strict meanings, and manufacturing errors and the like are allowed.

  The gyro vibrating piece 10 has a base 12 formed at a substantially central portion thereof. The base 12 is formed in a substantially rectangular shape having end faces parallel to the X-axis direction and the Y-axis direction, respectively. Connected to the base 12 are connecting arms 13 and 14 extending in the direction parallel to the X axis from the center of the two end faces parallel to the Y axis of the base 12.

  A pair of drive arms 15A, 15B, 15C, and 15D extending in a direction orthogonal to the connection arms 13 and 14 are connected to the tips of the connection arms 13 and 14 as drive units. More specifically, the driving arm 15A is connected to the tip of the connecting arm 13 in the Y-axis plus direction and the driving arm 15B is connected in the Y-axis minus direction. Further, a drive arm 15C is connected to the tip of the connecting arm 14 in the Y-axis plus direction and a drive arm 15D in the Y-axis minus direction. Drive adjusting portions 17A and 17B are formed at the respective tip portions of the drive arms 15A, 15B, 15C and 15D. That is, the drive adjustment portion 17A having a width that is wider than that of the drive arm 15A is provided at the tip portion of the drive arm 15A, and the drive adjustment portion 17B having a width that is greater than that of the drive arm 15B is provided at the tip portion of the drive arm 15B. It has been. Similarly, drive adjustment portions 17A and 17B are provided at the respective tip portions of the drive arm 15C and the drive arm 15D. The drive unit is set with dimensions and shapes such as the width and length of the drive arms 15A, 15B, 15C, and 15D or the drive adjustment units 17A and 17B so that the drive vibration has a predetermined resonance frequency.

  Further, the base 12 includes a detection arm 16A in the Y-axis plus direction and a detection arm in the Y-axis minus direction as a detection part extending in the direction parallel to the Y-axis from the center of the two end faces parallel to the X-axis of the base 12. 16B is connected. At the distal end portions of the detection arms 16A and 16B, the detection adjustment units 18A. 18B is formed. That is, the detection adjustment portion 18A having a width wider than that of the detection arm 16A is provided at the distal end portion of the detection arm 16A, and the detection adjustment portion 18B having a width larger than that of the detection arm 16B is provided at the distal end portion of the detection arm 16B. It has been. In the detection unit, dimensions and shapes such as the width and length of the detection arms 16A and 16B or the detection adjustment units 18A and 18B are set so that the detection vibration has a predetermined resonance frequency.

  Next, the vibration operation of the gyro vibrating piece 10 will be described. 2 and 3 are plan views for schematically explaining the operation of the gyro vibrating piece 10 of the present embodiment. In FIG. 2 and FIG. 3, in order to express the vibration form in an easy-to-understand manner, each vibration arm is simplified and represented by a line, and the detection adjustment unit and the drive adjustment unit are omitted. The same components as those in FIG. 1 are denoted by the same reference numerals and description thereof is omitted. Note that the vibration operation of the gyro vibrating piece 10 described here is also referred to as in-plane bending vibration mode vibration.

  FIG. 2 is a diagram for explaining drive vibration. In FIG. 2, the drive vibration is a flexural vibration in which the drive arms 15A, 15B, 15C, and 15D vibrate in the direction of arrow A, and the vibration state indicated by the solid line and the vibration state indicated by the two-dot chain line are repeated at a predetermined frequency. ing. This frequency is called a drive vibration frequency (fd). At this time, since the drive arms 15A and 15B and the drive arms 15C and 15D are oscillating line-symmetrically with respect to the Y axis passing through the gravity center position G, the base 12, the connecting arms 13 and 14, and the detection arms 16A and 16B are Almost no vibration.

  FIG. 3 is a diagram for explaining the detected vibration. In FIG. 3, the detected vibration repeats a vibration state indicated by a solid line and a vibration state indicated by a two-dot chain line at a frequency substantially equal to the drive vibration frequency fd described above. The detected vibration is applied to the drive arms 15A, 15B and 15C, 15D when a rotational angular velocity ω around the Z-axis is applied to the gyro vibrating piece 10 while the gyro vibrating piece 10 performs the driving vibration shown in FIG. It is generated by the Coriolis force in the direction indicated by the arrow B.

  As a result, the drive arms 15A, 15B, 15C, and 15D perform the vibration indicated by the arrow B. The vibration indicated by the arrow B is a vibration in the circumferential direction with respect to the gravity center position G. At the same time, the detection arms 16A and 16B vibrate in the direction opposite to the circumferential direction of the arrow B in response to the vibration of the arrow B as indicated by the arrow C.

  At this time, the peripheral portion of the base 12 is in a balanced state as a vibration system when the drive arms 15A, 15B, 15C, 15D and the detection arms 16A, 16B vibrate as shown in FIG. Does not vibrate. Therefore, even if a support member that supports the gyro vibrating piece 10 is connected to the base portion 12, the vibration of the gyro vibrating piece 10 is not affected.

  Next, the vibration operation in the out-of-plane bending vibration mode (hereinafter referred to as “out-of-plane bending mode”) of the gyro vibrating piece 10 of this embodiment will be described. This out-of-plane bending mode vibrates at a predetermined vibration frequency. The vibration in the out-of-plane bending mode includes an out-of-plane bending primary mode that vibrates at an out-of-plane bending primary mode vibration frequency fs1 and an out-of-plane bending secondary mode that vibrates at an out-of-plane bending secondary mode vibration frequency fs2. .

  FIG. 4 is a schematic diagram for schematically explaining the vibration operation in the out-of-plane bending primary mode, where (a) is a perspective view, (b) is a plan view, and (c) is viewed from the Y-axis direction. It is a front view. FIG. 5 is a schematic diagram for schematically explaining the vibration operation in the out-of-plane bending secondary mode, where (a) is a perspective view, (b) is a plan view, and (c) is viewed from the Y-axis direction. It is a front view. 4 and 5 show the form of the gyro vibrating piece at a certain point in time.

  First, the vibration operation in the out-of-plane bending primary mode will be described with reference to FIG. As shown in FIG. 4, in the out-of-plane bending primary mode, one connecting arm 13 and the other connecting arm 14 bend and vibrate in a direction substantially perpendicular to the XY plane (Z-axis direction) ( (Indicated by arrows A7, A6, B7, B6). FIG. 4 shows, as an example, the moment when the connecting arm 13 is displaced in the direction indicated by the arrow A7 with respect to the XY plane, and the connecting arm 14 is displaced in the direction indicated by the arrow A6 with respect to the XY plane. ing.

The vibration in the out-of-plane bending primary mode is such that the displacement of the connecting arm 13 (arrows A7 and B7) and the displacement of the connecting arm 14 (arrows A6 and B6) with respect to the XY plane are opposite in any instant. It is a vibration that goes out of phase. When the displacement between the connecting arm 13 and the connecting arm 14 shown in FIG. 4 is indicated by arrows A7 and A6, the directions of the arrows A9 and A10 are such that the drive arms 15A, 15B, 15C, and 15D rotate about the Y axis. It is displaced to. The displacement directions of the drive arms 15A, 15B, 15C, and 15D are directions along the displacement directions of the connecting arms 13 and 14.
The displacement directions of the drive arms 15A, 15B, 15C and 15D are reversed as the displacement of the connecting arms 13 and 14 is reversed (arrows B7 and B6), and are displaced in the directions of arrows B9 and B10. .

  Similarly, when the displacement between the connection arm 13 and the connection arm 14 is indicated by arrows A7 and A6, the detection arms 16A and 16B are displaced in the direction of the arrow A8 that rotates about the Y axis. The displacement directions of the detection arms 16A and 16B are reversed as the displacement of the connecting arms 13 and 14 is reversed (arrows B7 and B6), and are displaced in the direction of the arrow B8. The vibration operation in the out-of-plane bending primary mode is performed at the out-of-plane bending primary mode vibration frequency fs1 by repeating the above-described displacement.

  Next, the out-of-plane bending secondary mode will be described with reference to FIG. As shown in FIG. 5, in the out-of-plane bending secondary mode, as in the first out-of-plane bending vibration mode, one connecting arm 13 and the other connecting arm 14 are substantially perpendicular to the XY plane. Bends and vibrates in the direction (Z-axis direction) (indicated by arrows A1, A2, B1, and B2). FIG. 5 shows, as an example, the moment when the connecting arm 13 is displaced in the direction indicated by the arrow A2 with respect to the XY plane and the connecting arm 14 is displaced in the direction indicated by the arrow A1 with respect to the XY plane. ing.

In this out-of-plane bending mode vibration, the displacement of the connecting arm 13 with respect to the XY plane (arrows A2 and B2) and the displacement of the connecting arm 14 (arrows A1 and B1) are in opposite directions at any moment, that is, It is a vibration that goes out of phase. When the displacement between the connecting arm 13 and the connecting arm 14 shown in FIG. 5 is indicated by arrows A2 and A1, the directions of the arrows A4 and A5 are such that the drive arms 15A, 15B, 15C, and 15D rotate about the Y axis. It is displaced to.
The displacement directions of the drive arms 15A, 15B, 15C, 15D are opposite to the displacement directions of the connecting arms 13, 14.
The displacement directions of the drive arms 15A, 15B, 15C, 15D are reversed as the displacement of the connecting arms 13, 14 is reversed (arrows B2, B1), and are displaced in the directions of arrows B4, B5. .

  Similarly, when the displacement between the connecting arm 13 and the connecting arm 14 is indicated by arrows A2 and A1, the detection arms 16A and 16B are displaced in the direction of the arrow A3 that rotates about the Y axis. The displacement directions of the detection arms 16A and 16B are reversed as the displacement of the connecting arms 13 and 14 is reversed (arrows B2 and B1), and are displaced in the direction of the arrow B3. The vibration operation in the out-of-plane bending secondary mode is performed at the out-of-plane bending secondary mode vibration frequency fs2 by repeating the above-described displacement.

  As the gyro vibrating piece 10 is reduced in size, the inventor has three times higher harmonic components and out-of-plane bending of the drive vibration frequency fd (hereinafter, drive vibration frequency may be abbreviated as “fd”). Primary mode vibration frequency fs1 (hereinafter, the out-of-plane bending primary mode vibration frequency is sometimes referred to as “fs1”), or out-of-plane bending secondary mode vibration frequency fs2 (hereinafter, out-of-plane bending secondary mode vibration). We focused on the fact that the frequency is sometimes omitted and is sometimes referred to as “fs2”. Then, it was found that the vibration of the driving vibration frequency fd and the vibration of the out-of-plane bending primary mode vibration frequency fs1 or the out-of-plane bending secondary mode vibration frequency fs2 interfere with each other or combine to bring about a temperature drift. . It was confirmed that this temperature drift can be suppressed by separating the driving vibration frequency fd from the out-of-plane bending primary mode vibration frequency fs1 or the out-of-plane bending secondary mode vibration frequency fs2.

  The vibration frequencies of the out-of-plane bending primary mode vibration frequency fs1 and the out-of-plane bending secondary mode vibration frequency fs2 are the masses and shapes of the drive adjustment units 17A and 17B and the detection adjustment units 18A and 18B, as shown in FIG. Etc. can be adjusted by changing the above. This frequency adjustment can be performed, for example, by changing the dimensional ratio of the width dimension Wd of the drive adjustment units 17A and 17B and the width dimension Wde of the detection adjustment units 18A and 18B and the width dimension Wa of the gyro vibrating piece 10. . It is also possible to remove the length or a weight layer (not shown) formed on the surface thereof.

Hereinafter, a preferred embodiment of the gyro vibrating piece 10 used for suppressing temperature drift will be described and described.
In the embodiment shown here, as an example of the gyro vibrating piece 10, a double T-type gyro vibrating piece (hereinafter referred to as a “vibrating piece”) having a driving vibration frequency fd of 80.6 KHz, whose outer dimensions are approximately within 2 mm square. Using.
Example 1

Various vibration pieces were produced by changing the out-of-plane bending primary mode vibration frequency fs1 so that fs1 / fd was between 1.8 and 4.2, and the temperature of the frequency due to the temperature change of each vibration piece. The amount of drift (hereinafter referred to as “drift amount”) was confirmed.
Here, fs1 / fd is obtained by dividing the out-of-plane bending primary mode vibration frequency fs1 by the driving vibration frequency fd, and the out-of-plane bending primary mode vibration frequency fs1 is a multiple of the driving vibration frequency fd. It shows that. The result is shown in the graph of FIG.

FIG. 6 is a graph showing the correlation between fs1 and the drift amount of the resonator element. The horizontal axis represents the value of fs1 / fd, and the vertical axis represents the drift amount exponentially. As shown in FIG. 6, when fs1 / fd is not less than 2.2 and not more than 2.8, or is in the range not less than 3.2 and not more than 3.8, the drift amount is larger than the standard line L indicated by the broken line in the figure. You can see that it is getting smaller. In other words, by setting the out-of-plane bending primary mode vibration frequency fs1 to 2.2 times or more and 2.8 times or less, or 3.2 times or more and 3.8 times or less of the driving vibration frequency fd, the drift amount is more than the standard. It can be kept small. The range in which this drift amount can be kept smaller than the standard is fd × 2.2 ≦ fs1 ≦ fd × 2.8, or fd × 3.2 ≦ fs1 ≦ fd × 3.8. The standard line L is obtained by replacing a value for which drift does not cause a practical problem with an index.
(Example 2)

  Furthermore, the out-of-plane bending primary mode vibration frequency fs1 is set to 2.2 ≦ fs1 / fd ≦ 2.8, and the fs2 / fd of the out-of-plane bending secondary mode vibration frequency fs2 is between 2.2 and 4. Various types of vibrating bars were prepared so that the frequency drift was changed, and the amount of frequency drift due to the temperature change of each vibrating bar was confirmed. Here, fs2 / fd is obtained by dividing the out-of-plane bending secondary mode vibration frequency fs2 by the driving vibration frequency fd, and the out-of-plane bending secondary mode vibration frequency fs2 is a multiple of the driving vibration frequency fd. It shows that. The result is shown in the graph of FIG.

  FIG. 7 is a graph showing the correlation between fs2 and the drift amount when the out-of-plane bending primary mode vibration frequency fs1 of the resonator element is 2.2 ≦ fs1 / fd ≦ 2.8. , Fs2 / fd, and the vertical axis represents the drift amount exponentially. As shown in FIG. 7, after setting the out-of-plane bending primary mode vibration frequency fs1 of the resonator element to 2.2 ≦ fs1 / fd ≦ 2.8, fs2 / By setting fd to a value between 2.2 and 4, the drift amount of the resonator element becomes a value significantly lower than the standard line L (this standard line L is the same as the standard line L shown in FIGS. 6 and 8). Values are shown.) That is, the drift amount of the resonator element can be further reduced as compared with the first embodiment.

  According to the second embodiment, a particularly preferable setting range of the out-of-plane bending secondary mode vibration frequency fs2 is when fs2 / fd is more than 2.2 and not more than 2.8, that is, the out-of-plane bending of the resonator element. When the secondary mode vibration frequency fs2 is set to fs2 × 2.2 <fd ≦ fs2 × 2.8, or when fs2 / fd is 3.2 or more and 3.8 or less, that is, fs2 × 3.2 ≦ fd ≦ fs2. It is when it exists in the range when it is set as * 3.8.

The out-of-plane bending secondary mode vibration frequency fs2 exists on the higher frequency side than the out-of-plane bending primary mode vibration frequency fs1. Therefore, in FIG. 7, fs2 / fd is plotted from 2.4, but theoretically, fs2 only needs to exceed fs1 × 2.2, and fs2 / fd exceeds 2.2. A range of 8 or less is considered suitable.
(Example 3)

  The out-of-plane bending primary mode vibration frequency fs1 is set to 3.2 ≦ fs1 / fd ≦ 3.8, and the fs2 / fd of the out-of-plane bending secondary mode vibration frequency fs2 is between 3.2 and 3.8. Various types of vibrating bars were prepared so that the frequency drift was changed, and the amount of frequency drift due to the temperature change of each vibrating bar was confirmed. Since the description of fs2 / fd is the same as that of the second embodiment, a description thereof will be omitted. The result is shown in the graph of FIG.

  FIG. 8 is a graph showing the correlation between fs2 and the drift amount when fs1 of the resonator element is 3.2 ≦ fs1 / fd ≦ 3.8, and the horizontal axis represents the value of fs2 / fd. The vertical axis represents the amount of drift exponentially. As shown in FIG. 8, after setting the out-of-plane bending primary mode vibration frequency fs1 of the resonator element to 3.2 ≦ fs1 / fd ≦ 3.8, fs2 / By setting fd between 3.2 and 4, the drift amount of the resonator element becomes a value significantly lower than the standard line L as in Example 2 (this standard line L is shown in FIGS. 6 and 7). It shows the same value as the standard line L shown). That is, the drift amount of the resonator element can be further reduced as compared with the first embodiment.

According to the third embodiment, a particularly preferable setting range of the above-described out-of-plane bending secondary mode vibration frequency fs2 is when fs2 / fd is more than 3.2 and less than 3.8, that is, the surface of the vibration piece. This is when the outer bending secondary mode vibration frequency fs2 is in a range where fs2 × 3.2 <fd ≦ fs2 × 3.8.
The out-of-plane bending secondary mode vibration frequency fs2 exists on the higher frequency side than the out-of-plane bending primary mode vibration frequency fs1. Therefore, in FIG. 7, fs2 / fd is a plot from 3.4, but fs2 should theoretically exceed fs1 × 3.2, and fs2 / fd exceeds 3.2. A range of 8 or less is considered suitable.

  As described above, the gyro vibrating piece 10 has the out-of-plane bending primary mode vibration frequency fs1, the out-of-plane bending secondary mode vibration frequency fs2, and the driving vibration frequency fd of the vibrating piece in the first to third embodiments. By using the relationship as described, it is possible to suppress the drift amount (temperature drift amount) due to temperature change to a level that does not cause a problem in practice.

  The correlation between the out-of-plane bending primary mode vibration frequency fs1 and the out-of-plane bending secondary mode vibration frequency fs2 and the driving vibration frequency fd of the resonator element is shown in the graph of FIG. The range of the cross-hatching portions 50, 51, and 52 shown in FIG. 9 indicates a particularly preferable range where the temperature drift is small, and the oblique hatching portions 53a, 53b, and 53c indicate a preferable range where the temperature drift is small. Note that the upper left side of the dividing line D in FIG. 9 is a range that does not exist because of the relationship of fs2> fs1.

  The gyro vibrating piece 10 described above can be used as a gyro sensor housed together with a circuit element having a sensor driving circuit or the like in a housing package made of, for example, ceramic. The gyro sensor has a support substrate connected to the bottom of a recess formed in the storage package, and has a function of at least driving the gyro vibrating piece 10 and a support arm for supporting the gyro vibrating piece 10 on the support substrate. Circuit elements are connected. Further, the base of the gyro vibrating piece is connected to one end of the support arm to hold the gyro vibrating piece 10. These members are stored in the storage package and hermetically sealed by joining the opening of the storage package with the lid. At this time, the inside of the storage container is often decompressed.

  In the above-described embodiment, the gyro vibrating piece has been described by exemplifying a so-called double T (double tee) type gyro vibrating piece, but is not limited thereto. For example, the present invention can be applied to an electrode of a gyro vibrating piece such as a tuning fork type gyro vibrating piece or an H (etch) type gyro vibrating piece, and has similar effects.

The top view which shows typically the schematic structure of a gyro vibrating piece. The figure explaining the drive vibration of a gyro vibration piece. The figure explaining the detection vibration of a gyro vibration piece. It is the schematic for demonstrating typically the vibration operation | movement of the out-of-plane bending primary mode of a gyro vibrating piece, (a) is a perspective view, (b) is a top view, (c) was seen from the Y-axis direction. Front view. It is the schematic for demonstrating the vibration operation | movement of an out-of-plane bending secondary mode of a gyro vibrating piece typically, (a) is a perspective view, (b) is a top view, (c) was seen from the Y-axis direction. Front view. 6 is a graph showing the correlation between fs1 and the drift amount of the resonator element of Example 1. FIG. 6 is a graph showing the correlation between fs1 and the drift amount of the resonator element of Example 2. 10 is a graph showing the correlation between fs1 and the drift amount of the resonator element of Example 3. The graph which shows the correlation of fs1 and fs2 which can suppress a temperature drift, and fd.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Gyro vibrating piece, 12 ... Base part, 13, 14 ... Connection arm as support beam, 15A, 15B, 15C, 15D ... Drive arm as drive part, 16A, 16B ... Detection arm as detection part, 17A, 17B ... drive adjustment unit, 18A, 18B ... detection adjustment unit.

Claims (5)

A base part, a drive part provided through a support beam extending from the base part, having a predetermined drive vibration frequency fd, and extending from the base part in the same plane as the drive part, and rotating the drive part A gyro vibrating piece having a detection unit for detecting detection vibration caused by Coriolis force accompanying
The gyro vibrating piece has an out-of-plane bending primary mode vibration and an out-of-plane bending secondary mode vibration, and the out-of-plane bending primary mode vibration frequency fs1 is fd × 2.2 ≦ fs1 ≦ fd × 2.8, or A gyro vibrating piece formed so as to satisfy any of fd × 3.2 ≦ fs1 ≦ fd × 3.8. The gyro vibrating piece according to claim 1,
The out-of-plane bending secondary mode vibration frequency fs2 is formed so that either fd × 2.2 <fs2 ≦ fd × 2.8 or fd × 3.2 ≦ fs2 ≦ fd × 3.8. A gyro vibrating piece characterized by that. The gyro vibrating piece according to claim 1,
The out-of-plane bending primary mode vibration frequency fs1 is fd × 2.2 ≦ fs1 ≦ fd × 2.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 3.2 ≦ fs2 ≦ fd × 3. A gyro vibrating piece characterized by being 8. The gyro vibrating piece according to claim 1,
The out-of-plane bending primary mode vibration frequency fs1 is fd × 2.2 ≦ fs1 ≦ fd × 2.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 2.2 <fs2 ≦ fd × 2. A gyro vibrating piece characterized by being 8. The gyro vibrating piece according to claim 1,
The out-of-plane bending primary mode vibration frequency fs1 is fd × 3.2 ≦ fs1 ≦ fd × 3.8, and the out-of-plane bending secondary mode vibration frequency fs2 is fd × 3.2 <fs2 ≦ fd × 3 · A gyro vibrating piece characterized by being 8.

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