JP5428241B2 - Gyro vibrator and method for manufacturing gyro vibrator - Google Patents

Description

  The present invention relates to a gyro vibrator in which a gyro element is mounted in a package and a method for manufacturing the gyro vibrator.

As an angular velocity sensor (hereinafter referred to as a gyro sensor) for detecting an angular velocity, a vibration body (hereinafter referred to as a gyro element), driving means for vibrating the gyro element in a predetermined direction, and vibration of the gyro element based on Coriolis force are detected. A gyro sensor provided with a detecting means is known (for example, see Patent Document 1).
In this gyro sensor, a gap having a height larger than the thickness of the gyro element is provided between a movable part of the gyro element (hereinafter referred to as a vibrating arm part) and a wiring board (hereinafter referred to as a base part) on which the gyro element is mounted. Is formed.

JP 2000-97709 A

  Similar to the above gyro sensor, gyro vibrators with gyro elements mounted on the base of the package have been promoted to be smaller and thinner (low profile) as the mounted electronic devices have become smaller. Yes. In the gyro vibrator, the inside of the package is sealed in a vacuum state free from the influence of air resistance in order to obtain stable vibration of the gyro element.

The gyro vibrator performs balance tuning by adjusting the balance of the mass of each vibrating arm by vibrating each vibrating arm. When the balance tuning process is performed in the atmosphere, the vibrating arm portion with a large gap amount with the base portion is easy to vibrate because the air resistance is small, and the vibrating arm portion with a small gap amount with the base portion has an air resistance. Because it is large, it is hard to vibrate.
When the gyro vibrator is reduced in size and thickness, the gap between the base portion and the vibrating arm portion is reduced, and the influence of air resistance on the ease of vibration of the vibrating arm portion is large.
In addition, since the gyro element is inclined and mounted on the base portion due to manufacturing variations, there are a vibrating arm portion having a relatively large gap with the base portion and a vibrating arm portion having a small gap with the base portion.

  For these reasons, the gyro vibrator is in a vacuum state where the balance of each vibrating arm is tuned based on the vibration state of each vibrating arm in the atmosphere affected by air resistance, and the inside of the package is not affected by air resistance. By sealing with, there is a problem that the vibration state of each vibration arm portion is changed to be in an unbalanced state.

SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.
[First embodiment]
It includes a base, a driving vibration arms which is extended from the base portion, and a vibration arms for detection that are extended from the base portion, and a gyro element are tabular,
The has a base portion that is equipped with a gyro element, and a package interior you are accommodating the gyro element is vacuum-sealed,
Between the base portion and the driving vibrating arm portion, there is a first gap,
A second gap is provided between the base portion and the detection vibrating arm portion;
The gyro vibrator according to claim 1, wherein the first gap is larger than the second gap.
[Second form]
In the gyro vibrator according to the first embodiment,
Before SL base portion has a first layer and a second layer that are stacked,
The first layer, said having a mounting surface mounted with the gyro device, an opening in a region above that not face the drive vibration arms of the gyro device,
Between the mounting surface and the detection vibrating arm portion, the second gap is provided,
The second layer has a closing surface that Ide busy the second layer side of the opening,
Between the closing surface and the drive vibration arms, a gyro vibrator characterized that you have to have a first void.
[Third embodiment]
In the gyro vibrator according to the second embodiment,
The gyro element includes a fixed portion connected to the base portion,
The gyro vibrator according to claim 1, wherein the fixing portion is fixed to the mounting surface of the first layer.
[Fourth form]
In the gyro vibrator according to any one of the first to third aspects,
The gyro vibrator according to claim 1, wherein a vibration direction of the driving vibration arm portion and the detection vibration arm portion is a direction along a main surface of the gyro element.
[Fifth embodiment]

A gyro element having a base, a driving vibration arm extending from the base, and a detection vibrating arm extending from the base, and having a flat plate shape, and the gyro element mounted thereon Prepare a package with a base part,
The gyro is positioned at a position where a first gap between the base and the driving vibrating arm is larger than a second gap between the base and the detecting vibrating arm. A mounting process for mounting elements;
A balance tuning step of adjusting the balance of the drive vibrating arm by changing the mass of the drive vibrating arm in the atmosphere;
And a sealing step for vacuum-sealing the package.

  Application Example 1 A gyro vibrator according to this application example includes a base, a driving vibrating arm extending from the base, and a detecting vibrating arm extending from the base. And a gyro element formed in a flat plate shape, and a package having a base portion on which the gyro element is mounted, and the inside for accommodating the gyro element being vacuum-sealed, and the base portion of the package and the A first gap and a second gap are provided between the gyro element, the first gap is larger than the second gap, and the first gap is formed between the base portion and the drive unit. It is provided between the vibrating arm portion.

  According to this, the gyro vibrator has the first gap and the second gap between the base portion of the package and the gyro element, the first gap being larger than the second gap, One gap is provided between the base portion and the vibrating arm portion for driving the gyro element.

Thus, the gyro vibrator reduces the air resistance with respect to each driving vibration arm portion, and the difference in air resistance with respect to each driving vibration arm portion due to the inclination of the gyro element or the like is reduced.
Therefore, the gyro vibrator is in an unbalanced state by sealing the balance of each drive vibration arm that is tuned in the atmosphere affected by air resistance in a vacuum state that is not affected by air resistance. The trouble of becoming can be reduced.
Further, the gyro vibrator is provided with the first gap only between the base portion and the driving vibration arm portion of the gyro element, and the periphery is set as the second gap. The same level can be maintained.

  Application Example 2 In the gyro vibrator according to the application example, it is preferable that the second gap is provided between the base portion and the detection vibrating arm portion.

  According to this, since the second gap is provided between the base portion and the vibrating arm portion for detection, the gyro vibrator, for example, at the time of balance tuning of each driving vibrating arm portion, The vibration of the vibration arm for detection accompanying the vibration of the vibration arm for driving can be stabilized quickly by reducing the Q value by the air resistance. From this, the gyro vibrator can shorten the detection time in the detection vibration arm portion at the time of balance tuning of each drive vibration arm portion.

  Application Example 3 In the gyro vibrator according to the application example described above, it is preferable that the vibration directions of the driving vibration arm portion and the detection vibration arm portion are in a direction along a main surface of the gyro element.

According to this, in the gyro vibrator, since the vibration directions of the driving vibration arm portion and the detection vibration arm portion are directions along the main surface of the gyro element, the gyro vibrator is in a direction intersecting with the main surface of the gyro element. There is no need to provide a relief portion accompanying the vibration of each vibrating arm portion in the thickness direction of a certain package.
For this reason, the gyro vibrator can be made thinner as compared with a gyro vibrator having a vibration direction different from that described above.

  Application Example 4 In the gyro vibrator according to the application example described above, the base portion of the package has a stacked first layer and second layer, and the first layer has a mounting surface of the gyro element. And the second gap is provided between the gyro element and the mounting surface, and an opening is provided in a region facing the driving vibration arm part of the gyro element, and the second layer Preferably has a closed surface for closing the second layer side of the opening, and the first gap is provided between the gyro element and the closed surface.

  According to this, in the gyro vibrator, the base portion has the first layer and the second layer, the first layer has the mounting surface of the gyro element, and the second gap is provided between the gyro element and the mounting surface. Are provided, and an opening is provided in a region facing the vibrating arm portion for driving the gyro element. The gyro vibrator has a closed surface in which the second layer closes the second layer side of the opening, and a first gap is provided between the gyro element and the closed surface.

  From this, the gyro vibrator is formed by laminating the base portion of the package by laminating the first layer having the opening and the second layer having the closing surface that closes the second layer side of the opening. The first gap and the second gap can be easily provided.

  Application Example 5 In the gyro vibrator according to the application example described above, the base portion has a stepped through hole for sealing that penetrates the first layer and the second layer, and the stepped portion in plan view. The second through hole formed in the second layer constituting the through hole is preferably larger than the first through hole formed in the first layer.

  According to this, the gyro vibrator has a stepped through hole for sealing in the base portion, and the second through hole formed in the second layer is larger than the first through hole formed in the first layer. . Therefore, in the gyro vibrator, for example, if the sealing member is formed larger than the first through hole and smaller than the second through hole, the sealing member stays in the second through hole and the first through hole is formed. The stepped through hole can be sealed while avoiding falling from the hole into the package.

  Application Example 6 In the gyro vibrator according to the application example, it is preferable that the stepped through hole is formed in a region of the base portion that overlaps the base portion of the gyro element in a plan view.

According to this, since the stepped through hole is formed in the region of the base portion that overlaps with the base portion of the gyro element in plan view, the gyro vibrator does not overlap with each vibrating arm portion.
From this, the gyro vibrator can avoid a change in air resistance in the atmosphere due to a part of each vibrating arm portion overlapping the stepped through hole, and can avoid an influence on balance tuning.

  In the gyro vibrator according to the application example, it is preferable that the package includes a metal lid.

  According to this, since the package includes the metal lid, the strength of the package can be improved as compared with the lid made of other materials. For this reason, the gyro vibrator can be further reduced in thickness.

  Application Example 7 A method for manufacturing a gyro vibrator according to this application example includes a base, a driving vibrating arm extending from the base, and a detecting vibrating arm extending from the base. A gyro element formed in a flat plate shape has a base portion on which the gyro element is mounted, a first gap between the base portion and the gyro element, and the first gyro element A mounting step of mounting the gyro element on the base portion at a position where the space between the base portion and the driving vibration arm portion of the package having the second space smaller than the space becomes the first space. And a balance tuning step for adjusting the balance of the driving vibration arm portion by changing the mass of the driving vibration arm portion in the atmosphere, and a sealing step for vacuum-sealing the package. Features.

  According to this, the method for manufacturing the gyro vibrator can obtain the gyro vibrator having the effect described in the application example.

  Application Example 8 In the gyro vibrator manufacturing method according to the application example, the base portion has a through hole, and the sealing member is filled in the through hole of the base portion in the sealing step. It is preferable to vacuum seal.

  According to this, since the manufacturing method of the gyro vibrator fills the through hole of the base portion with the sealing member in the sealing process and vacuum seals the package, the package can be easily vacuumed by a general-purpose method. It can be sealed.

  Hereinafter, embodiments of the gyro vibrator will be described with reference to the drawings.

(Embodiment)
FIG. 1 is a schematic diagram illustrating a schematic configuration of a gyro vibrator according to the present embodiment. 1A is a plan view, FIG. 1B is a cross-sectional view taken along line AA in FIG. 1A, and FIG. 1C is a cross-sectional view taken along line BB in FIG. It is sectional drawing in a line. In the plan view, a lid (lid) is omitted for easy understanding.
As shown in FIG. 1, the gyro vibrator 1 includes a gyro element 10, a package 20 that houses the gyro element 10, a fixing member 30 that fixes the gyro element 10 to the package 20, and the like.

The gyro element 10 is made of a piezoelectric material such as quartz and has a substantially rectangular base portion 11 and a plurality of vibrating arm portions extending from the base portion 11.
The gyro element 10 includes a pair of detection vibrating arm portions 12a and 12b extending from one end of the base portion 11, and a base portion in a direction substantially orthogonal to the extending direction of the detection vibrating arm portions 12a and 12b. 11, a pair of connecting arm portions 13a and 13b are extended from both ends of the other end of the connecting arm portions 13a and 13b along the extending direction of the detection vibrating arm portions 12a and 12b. And two pairs of drive vibrating arm portions 14a, 14b, 15a, 15b.
The driving vibrating arm portions 14a, 14b, 15a, and 15b are extended from the base portion 11 via the connecting arm portions 13a and 13b.

The gyro element 10 further extends in the direction substantially orthogonal to the extending direction of each vibrating arm portion in the vicinity of the distal ends of the detecting vibrating arm portions 12a, 12b and the driving vibrating arm portions 14a, 14b, 15a, 15b. The pair of fixed portions 16a, 16b and the other end of the base 11 are bent in a substantially crank shape between the detection vibrating arm portions 12a, 12b and the driving vibrating arm portions 14a, 14b, 15a, 15b. And support beam portions 17a and 17b connected to the fixed portion 16a and support beam portions 18a and 18b connected to the fixed portion 16b.
The gyro element 10 has an outer shape formed by removing unnecessary portions by etching or the like from a substantially rectangular and flat crystal substrate polished to a predetermined thickness.

The hammer head portions 14c, 14d, 15c, and 15d as the wide weight portions formed at the distal ends of the drive vibration arm portions 14a, 14b, 15a, and 15b of the gyro element 10 include the drive vibration arm portions 14a and 14b. , 15a, 15b are provided for mass adjustment films 14e, 14f, 15e, 15f used for balance tuning. The mass adjustment films 14e, 14f, 15e, and 15f are made of a metal thin film such as gold.
In the gyro element 10, hammer head portions 12c and 12d are also formed at the tip portions of the detection vibrating arm portions 12a and 12b.

Electrode pads 16c are provided on the fixing portions 16a and 16b of the gyro element 10, and are connected to electrodes (not shown) formed on the respective vibrating arm portions.
The gyro element 10 having such a shape is called a WT type gyro element and has high angular velocity detection sensitivity and can contribute to downsizing of the gyro vibrator 1.

The package 20 includes a base portion 21 on which the gyro element 10 is mounted, a frame portion 22, a seam ring 23, a lid 24, and the like.
The base portion 21 is formed by laminating a first layer 21a and a second layer 21b made of a flat ceramic green sheet or the like so that the inside of the package 20 becomes the first layer 21a and the outside becomes the second layer 21b. It is formed by.

The first layer 21a has a mounting surface 21c for the gyro element 10, and a second gap L2 is provided between the detection vibrating arm portions 12a and 12b of the gyro element 10 as shown in FIG. It has been. The second gap L2 is preferably provided in a region of the detection vibrating arm portions 12a and 12b facing at least the hammer head portions 12c and 12d.
The first layer 21 a includes an opening 21 d in each region facing the drive vibrating arm portions 14 a, 14 b, 15 a, and 15 b of the gyro element 10. Note that the planar shape of the opening 21d is formed in a substantially rectangular shape, and is preferably a size that can accommodate the hammer head portions 14c, 14d, 15c, and 15d of the driving vibration arm portions 14a, 14b, 15a, and 15b during vibration. .
An internal terminal 21i is formed on the mounting surface 21c of the first layer 21a, and is connected to the electrode pads 16c of the fixing portions 16a and 16b of the gyro element 10 through a fixing member 30 made of a conductive adhesive or a bump. Yes.
As a result, in the gyro element 10, the fixing portions 16 a and 16 b are fixed to the base portion 21 via the fixing member 30.

The second layer 21b has a blocking surface 21e that closes the second layer 21b side of the opening 21d of the first layer 21a. As shown in FIG. A first gap L1 is provided between 14b, 15a, 15b and the closing surface 21e.
The relatively large first gap L1 is provided in the region of the blocking surface 21e facing at least the hammer head portions 14c, 14d, 15c, and 15d of the driving vibrating arm portions 14a, 14b, 15a, and 15b. Is preferred. This is because the hammer head portions 14c, 14d, 15c, and 15d have the largest displacement and are easily affected by air resistance. Further, between the drive vibration arm portions 14a, 14b, 15a, 15b excluding the hammer head portions 14c, 14d, 15c, 15d and the base portion 21, a second gap L2 smaller than the first gap L1 is formed. If so, the strength of the base portion 21 can be increased. The first gap L1 is larger than the second gap L2 by approximately the thickness of the first layer 21a.
An external terminal 21j is formed on the bottom surface of the second layer 21b, and is connected to the internal terminal 21i by an internal wiring (not shown). Thereby, the gyro vibrator 1 can input / output a drive signal, a detection signal and the like to / from the outside via the external terminal 21j.

The base portion 21 has a stepped through hole 21f for sealing that penetrates the first layer 21a and the second layer 21b. The stepped through hole 21f includes a first through hole 21g formed in the first layer 21a and a second through hole 21h formed in the second layer 21b.
The first through hole 21g and the second through hole 21h are formed so as to overlap each other so that the outline of the first through hole 21g is accommodated inside the outline of the second through hole 21h in plan view. Thus, the second through hole 21h is formed larger than the first through hole 21g.
The stepped through hole 21f is formed at a position overlapping the base 11 of the gyro element 10 in plan view. Further, the stepped through hole 21f is subjected to a metallization process in order to improve the wettability and adhesion of the sealing member 40.

  On the base portion 21, a frame portion 22 formed in a substantially rectangular frame shape is disposed so as to surround the gyro element 10. The frame portion 22 is made of a ceramic green sheet or the like, similar to the base portion 21, and is joined by being laminated on the base portion 21 and firing together.

The seam ring 23 is made of a metal such as Kovar, and is joined to the frame portion 22 by brazing or the like.
The lid 24 is made of a metal such as kovar, is disposed so as to cover the gyro element 10, and is joined to the seam ring 23 by seam welding or the like.

After joining the lid 24, the gyro vibrator 1 inverts the package 20 and puts the sealing member 40 made of gold-germanium alloy into the stepped through hole 21f in a state where the inside of the package 20 is evacuated, The stepped through hole 21f is sealed by overheating and melting. As a result, the inside of the package 20 of the gyro vibrator 1 is vacuum-sealed.
Note that the frame portion 22 of the package 20 is not required if a sufficient gap is secured between the gyro element 10 and the lid 24 by forming the seam ring 23 thicker than the gyro element 10. May be.

Here, the operation and balance tuning of the gyro element 10 will be described with reference to the drawings.
The gyro element 10 is configured to excite drive mode vibration, which is a normal vibration mode, and detection mode vibration, which is a vibration mode when an angular velocity is applied.
2A and 2B are schematic diagrams for explaining a vibration mode of the gyro element. FIG. 2A is an explanatory diagram of a driving mode, and FIG. 2B is an explanatory diagram of a detection mode. In FIG. 2, the fixing portion and the supporting beam portion are omitted for easy understanding.

As shown in FIG. 2A, in the driving mode of the gyro element 10, the vibrating arm portions 14a, 14b, 15a, 15b for driving are in the direction of the arrow C around the tip portions 13c, 13d of the connecting arm portions 13a, 13b. Bends and vibrates.
When a rotational angular velocity ω about the Z axis is applied to the gyro element 10 in this state, Coriolis force acts on the driving vibrating arm portions 14a, 14b, 15a, and 15b, and as shown in FIG. 13a and 13b bend and vibrate in the direction of arrow D about the base of the base 11 as the center. Then, the detection vibrating arms 12a and 12b are flexibly vibrated in the direction of arrow E around the root of the base 11 by the reaction.
A rotational angular velocity ω about the Z axis is calculated using electrical signals (detection signals) generated in the detection vibrating arms 12a and 12b by this bending vibration. The direction of these bending vibrations is the direction along the main surface 11 a of the gyro element 10.

Here, when the mass balance of the drive vibration arm portions 14a, 14b, 15a, and 15b is good, the drive vibration is canceled by the base 11, and leakage to the detection vibration arm portions 12a and 12b is small. When the mass of the driving vibration arm portions 14a, 14b, 15a, and 15b is unbalanced, the leakage of the driving vibration arm portion to the detection vibration arm portions 12a and 12b increases. This leakage of drive vibration gives vibration in the XY plane to the detection vibrating arms 12a and 12b. Further, the leakage of the drive vibration may give a displacement in the Z-axis direction to the detection vibrating arms 12a and 12b. The leakage of the drive vibration to the vibration arm portions 12a and 12b for detection appears as noise in the detection signal. That is, the unbalance of the mass of the drive vibrating arm portions 14a, 14b, 15a, 15b appears as an unbalance of the detection signals of the detection vibrating arm portions 12a, 12b.
Therefore, the difference between the detection signals of the detection vibrating arm portions 12a and 12b is measured, and the mass adjusting films 14e and 14b of the driving vibrating arm portions 14a, 14b, 15a, and 15b are set so that the difference falls within a predetermined range. 14f, 15e, and 15f are irradiated with laser light and trimmed to perform balance tuning of the driving vibrating arm portions 14a, 14b, 15a, and 15b.

Here, a method for manufacturing the gyro vibrator 1 will be described with reference to the drawings.
FIG. 3 is a schematic diagram illustrating a method for manufacturing the gyro vibrator.

  First, the gyro element 10 having the above-described configuration is formed using a photolithographic technique, an etching technique, or the like from a substantially rectangular and flat crystal substrate polished to a predetermined thickness.

[Mounting process]
Next, as shown in FIG. 3A, the gyro element 10 is mounted on the base portion 21 of the package 20 having the above-described configuration before the lid 24 is joined.
At this time, the fixing member 30 made of a conductive adhesive, a bump, or the like is applied to the internal terminal 21 i formed in advance on the mounting surface 21 c of the base portion 21. Then, the position of the internal terminal 21 i and the position of the electrode pad 16 c formed on the fixing portions 16 a and 16 b of the gyro element 10 are matched.
At the same time, the positions of the hammer head portions 14c, 14d, 15c, and 15d of the driving vibration arm portions 14a, 14b, 15a, and 15b of the gyro element 10 and the position of the opening portion 21d of the base portion 21 of the package 20 are matched.
Next, the fixing portions 16 a and 16 b of the gyro element 10 are fixed to the internal terminal 21 i via the fixing member 30. Thereby, the gyro element 10 is electrically connected to the internal terminal 21i.

[Balance tuning process]
Next, balance tuning shown in FIG. In the balance tuning process, the package 20 is stationary so that the angular velocity can be ignored, and the vibration arms for driving 14a, 14b, 15a, 15b of the gyro element 10 are flexibly vibrated by applying a drive signal in the atmosphere. The difference between the detection signals generated in the detection vibrating arms 12a and 12b is measured.
Here, the difference between the detection signals generated in the detection vibrating arm portions 12a and 12b tends to increase when the driving vibration arm portions 14a, 14b, 15a, and 15b are large in imbalance.
Next, the mass adjusting films 14e, 14f, 15e, and 15f of the driving vibrating arm portions 14a, 14b, 15a, and 15b are trimmed by irradiating a laser beam 50 or the like so that the difference falls within a predetermined range. By changing the mass of the vibrating arm portions 14a, 14b, 15a, 15b, the balance tuning of the driving vibrating arm portions 14a, 14b, 15a, 15b is performed.

At this time, a first gap L1 larger than the second gap L2 (see FIG. 3C) is provided between the drive vibrating arm portions 14a, 14b, 15a, and 15b and the closing surface 21e of the base portion 21. Is provided.
As a result, the gyro element 10 has reduced air resistance with respect to the driving vibration arm portions 14a, 14b, 15a, and 15b, and the driving vibration arm portions 14a, 14b, 15a, and 15b caused by the inclination of the gyro element 10 and the like. The difference in air resistance becomes difficult to appear remarkably.
Therefore, in the gyro element 10, the influence of the air resistance is reduced during the balance tuning of the driving vibrating arms 14a, 14b, 15a, 15b performed in the atmosphere.

[Sealing process]
Next, as shown in FIG. 3C, the lid 24 is joined to the seam ring 23 by seam welding or the like.
Next, as shown in FIG. 3D, with the package 20 turned over and the package 20 inside evacuated, a ball-shaped sealing member 40 is introduced into the stepped through hole 21f and melted by overheating. Thus, the sealing member 40 is filled into the stepped through hole 21f, and the stepped through hole 21f is sealed. Thereby, the inside of the package 20 is vacuum-sealed.
At this time, the outer diameter of the ball-shaped sealing member 40 is larger than the diameter of the first through hole 21g and smaller than the diameter of the second through hole 21h. From this, the ball-shaped sealing member 40 stays in the second through hole 21h and can be prevented from falling into the package 20 from the first through hole 21g. Further, the stepped through hole 21f is metallized and has good wettability and adhesion to the sealing member 40.

The manufacturing method of the gyro vibrator 1 can obtain the gyro vibrator 1 as shown in FIG. 1 through the above steps.
In the sealing process, the lid 24 is joined to the seam ring 23 in a vacuum so that the stepped through hole 21f is eliminated and the inside of the package 20 is joined by the lid 24 without using the sealing member 40. You may vacuum-seal.

  As described above, the gyro vibrator 1 has the first gap L1 and the second gap L2 between the base portion 21 of the package 20 and the gyro element 10, and the first gap L1 is the first gap L1. The first gap L <b> 1 is larger than the gap L <b> 2 of 2 and is provided between the base portion 21 and the driving vibrating arm portions 14 a, 14 b, 15 a, 15 b of the gyro element 10.

Thereby, in the gyro vibrator 1, the air resistance to the driving vibrating arm portions 14a, 14b, 15a, 15b is reduced, and the driving vibrating arm portions 14a, 14b, 15a, 15b due to the inclination of the gyro element 10 and the like. The difference in air resistance with respect to is reduced.
Therefore, since the gyro vibrator 1 is balance-tuned in a state where the difference in air resistance between the drive vibrating arms 14a, 14b, 15a, and 15b is small, the gyro element 10 is driven in a vacuum where the air resistance can be ignored. The unbalance of the vibrating arm portions 14a, 14b, 15a, 15b can be reduced.

  Further, in the gyro vibrator 1, the first gap L1 is provided only between the base portion 21 and the driving vibrating arms 14a, 14b, 15a, 15b of the gyro element 10, and the second gap is formed around the first gap L1. Since L2 is provided, the strength of the base portion 21 can be maintained at the same level as the conventional one.

In the gyro vibrator 1, since the second gap L2 is provided between the base portion 21 and the detection vibration arm portions 12a and 12b, the drive vibration arm portions 14a, 14b, 15a, and 15b are provided. During balance tuning, the vibration of the detection vibrating arms 12a and 12b can be stabilized quickly by the Q value being lowered by the air resistance.
From this, the gyro vibrator 1 can shorten the detection time in the detection vibration arm portions 12a and 12b at the time of balance tuning of the drive vibration arm portions 14a, 14b, 15a and 15b.

Further, in the gyro vibrator 1, the vibration directions of the driving vibration arm portions 14a, 14b, 15a, 15b and the detection vibration arm portions 12a, 12b are directions along the main surface 11a of the gyro element 10. In the thickness direction of the package 20, which is the direction intersecting the main surface 11 a of the gyro element 10, there is no need to provide a relief portion associated with the vibration of each vibrating arm portion.
Therefore, the gyro vibrator 1 can be made thinner as compared with other gyro vibrators in which the vibration direction of the gyro element 10 is different from the above.

Further, in the gyro vibrator 1, the base portion 21 has the first layer 21a and the second layer 21b, the first layer 21a has the mounting surface 21c of the gyro element 10, and the gyro element 10 and the mounting surface 21c A second gap L2 is provided between them.
The gyro vibrator 1 includes an opening 21d in a region where the first layer 21a faces the driving vibration arm portions 14a, 14b, 15a, and 15b of the gyro element 10. The gyro vibrator 1 has a closed surface 21e in which the second layer 21b closes the second layer 21b side of the opening 21d, and the first gap L1 is provided between the gyro element 10 and the closed surface 21e. ing.

  From this, the gyro vibrator 1 includes the base layer 21 on which the gyro element 10 is mounted, the first layer 21a having the opening 21d, and the second surface having the closing surface 21e that closes the second layer 21b side of the opening 21d. The first gap L1 and the second gap L2 can be easily provided by stacking the layer 21b.

  Further, the gyro vibrator 1 has a stepped through hole 21f for sealing in the base portion 21, and a first through hole in which a second through hole 21h formed in the second layer 21b is formed in the first layer 21a. It is larger than the hole 21g. For this reason, the gyro vibrator 1 is configured such that the ball-shaped sealing member 40 is formed larger than the first through hole 21g and smaller than the second through hole 21h, so that the sealing member 40 becomes the second through hole. The stepped through hole 21f can be sealed while staying in 21h and avoiding falling into the package 20 from the first through hole 21g.

  Further, since the gyro vibrator 1 is filled with the sealing member 40 in a vacuum state in the sealing stepped through-hole 21f formed in the base portion 21, the package 20 is sealed. In this way, the inside of the package 20 can be easily vacuum-sealed.

  Further, the gyro vibrator 1 is formed at a position where the stepped through hole 21f overlaps the base 11 of the gyro element 10 in a plan view. Accordingly, the gyro vibrator 1 can avoid a change in air resistance in the atmosphere due to a part of each vibrating arm portion overlapping the stepped through hole 21f, and can avoid an influence on balance tuning.

  In the gyro vibrator 1, since the package 20 includes the metal lid 24, the strength of the package 20 can be improved as compared with the lid 24 made of other materials. For this reason, the gyro vibrator 1 can be further reduced in thickness.

In the gyro vibrator 1, the base portion 21 may be integrally formed instead of the two-layer configuration as in the above embodiment.
In the gyro vibrator 1, the first gap L <b> 1 may be provided between the detection vibrating arm portions 12 a and 12 b and the base portion 21 of the gyro element 10.
According to this, the gyro vibrator 1 reduces the influence of air resistance on the vibration of the detection vibrating arm portions 12a and 12b during balance tuning of the driving vibrating arm portions 14a, 14b, 15a and 15b in the atmosphere. it can.

Note that the present invention can be applied to a gyro vibrator including a plurality of drive vibration arm portions and one or more detection vibration arm portions. For example, in addition to the gyro element 10 described above, the present invention can be applied to a gyro element 110 having a configuration as shown in a schematic diagram illustrating a schematic configuration of the gyro element in FIG.
As shown in FIG. 4, the gyro element 110 includes two drive vibration arm portions 114 and 115 and one detection vibration arm portion 112 extending from one end portion of the base portion 111 substantially parallel to each other. ing. Further, a fixing portion 116 is extended from the other end portion of the base portion 111.
A gyro vibrator (not shown) using the gyro element 110 has a first gap in a region facing the driving vibration arm portions 114 and 115 of the base portion of the package on which the gyro element 110 is mounted, as in the above embodiment. By providing the second gap in the region facing the detection vibrating arm portion 112, at least a part of the effect of the above embodiment can be obtained.

The schematic diagram which shows schematic structure of the gyro vibrator of this embodiment. The schematic diagram explaining the vibration mode of a gyro element. Schematic explaining the manufacturing method of a gyro vibrator. The schematic diagram which shows schematic structure of another gyro element.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Gyro vibrator, 10 ... Gyro element, 11 ... Base part, 11a ... Main surface, 12a, 12b ... Vibration arm part for detection, 13a, 13b ... Connection arm part, 14a, 14b, 15a, 15b ... Vibration arm for drive Part, 16a, 16b ... fixed part, 16c ... electrode pad, 17a, 17b, 18a, 18b ... support beam part, 20 ... package, 21 ... base part, 21a ... first layer, 21b ... second layer, 21c ... mounting Surface, 21d ... Opening, 21e ... Closed surface, 21f ... Stepped through hole, 21g ... First through hole, 21h ... Second through hole, 21i ... Internal terminal, 21j ... External terminal, 22 ... Frame part, 23 ... Seam ring, 24 ... lid, 30 ... fixing member, 40 ... sealing member, L1 ... first gap, L2 ... second gap.

Claims (5)

Includes a base, a driving vibration arms which is extended from the base portion, and a vibration arms for detection that are extended from the base portion, and a gyro element are tabular,
The has a base portion that is equipped with a gyro element, and a package interior you are accommodating the gyro element is vacuum-sealed,
Between the base portion and the driving vibrating arm portion, there is a first gap,
A second gap is provided between the base portion and the detection vibrating arm portion;
The gyro vibrator according to claim 1, wherein the first gap is larger than the second gap. The gyro vibrator according to claim 1,
Before SL base portion has a first layer and a second layer that are stacked,
The first layer, said having a mounting surface mounted with the gyro device, an opening in a region above that not face the drive vibration arms of the gyro device,
Between the mounting surface and the detection vibrating arm portion, the second gap is provided,
The second layer has a closing surface that Ide busy the second layer side of the opening,
Between the closing surface and the drive vibration arms, a gyro vibrator characterized that you have to have a first void. In the gyro vibrator according to claim 2 ,
The gyro element is provided with a fixed portion connected to the base portion,
The gyro vibrator according to claim 1, wherein the fixing portion is fixed to the mounting surface of the first layer. In the gyro vibrator according to any one of claims 1 to 3 ,
The gyro vibrator according to claim 1, wherein a vibration direction of the driving vibration arm portion and the detection vibration arm portion is a direction along a main surface of the gyro element. Includes a base, a driving vibration arms which is extended from the base portion, and a vibration arms for detection that are extended from the base portion, mounted gyro element are tabular, and said gyro element providing a package having a Tei Ru base portion,
The gyro is positioned at a position where a first gap between the base and the driving vibrating arm is larger than a second gap between the base and the detecting vibrating arm. A mounting process for mounting elements;
A balance tuning step of adjusting the balance of the drive vibrating arm by changing the mass of the drive vibrating arm in the atmosphere;
And a sealing step for vacuum-sealing the package.

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