JP2015087145A - Vibration element, vibrator, electronic apparatus and mobile body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a vibration element, a vibrator, an electronic apparatus, and a mobile body capable of reducing temperature drift while sufficiently keeping mechanical strength.SOLUTION: A vibration element includes: a base part 21; a first support part 251 which supports the base part 21; and a first beam 261 which connects the base part 21 and the first support part 251. Moreover, in the beam 261, a through-hole 261C is formed through which the beam 261 penetrates in a width direction. As a result, the beam 261 is divided into an upper side beam part 261A and a lower side beam part 261B.

Description

  The present invention relates to a vibration element, a vibrator, an electronic device, and a moving body.

Conventionally, as a vibration element for detecting an angular velocity, a vibration element as in Patent Document 1 is known. The vibration element described in Patent Document 1 includes a base, first and second detection arms extending from the base along both sides in the Y-axis direction, and first and second extending from the base to both sides in the X-axis direction. Two connecting arms, first and second driving arms extending from the first connecting arm to both sides in the Y-axis direction, and third and fourth driving arms extending from the second connecting arm to both sides in the Y-axis direction; have. In the vibration element having such a configuration, when an angular velocity around the Z axis is applied in a state where each drive arm is vibrated in the drive mode, vibration in the detection mode is excited in the first and second detection arms, and the vibration in the detection mode. The angular velocity can be detected from the signal obtained by.
In recent years, the use of such vibration elements has been expanded, for example, in portable devices and in-vehicle devices. As a result, the temperature environment to be used is diverse, and it is required to operate stably in a wide temperature range. In addition, downsizing is also required.

In such a vibration element, even if the resonance frequency fd (Hz) of the first to fourth drive arms (hereinafter referred to as “drive vibration frequency fd”) is adjusted to a constant value at room temperature, the ambient temperature is high. 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 affected by unnecessary vibration such as an out-of-plane bending vibration mode. In order to suppress this temperature drift, for example, Patent Document 2 discloses that an out-of-plane bending primary mode vibration frequency fs1 as an out-of-plane bending mode is fd × 2.2 ≦ fs1 ≦ fd × 2.8, or fd × 3. .2 ≦ fs1 ≦ fd × 3.8 has been proposed.
However, although the above-described conventional vibration element is effective in the relationship between the drive vibration frequency fd and the out-of-plane bending mode vibration frequency fs, it is sufficiently effective for unnecessary vibration different from the out-of-plane bending vibration mode. However, further reduction in temperature drift has been demanded.

JP 2006-201011 A JP 2008-26110 A

  An object of the present invention is to provide a vibration element, a vibrator, an electronic device, and a moving body that can reduce temperature drift while maintaining sufficient mechanical strength.

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.
[Application Example 1]
The vibration element of the present invention includes a vibration part,
A support part for supporting the vibration part;
A beam connecting the vibrating portion and the support portion;
The beam has a through-hole penetrating two different places on the surface of the beam.
As a result, it is possible to obtain a vibration element capable of reducing temperature drift while maintaining sufficient mechanical strength.

[Application Example 2]
In the vibration element according to this application example, it is preferable that the through-hole penetrates through two locations in the thickness direction of the vibration portion of the beam.
As a result, the vibration element is particularly resistant to an in-plane impact of the vibration part.
[Application Example 3]
In the vibration element according to this application example, it is preferable that the through-hole penetrates through two locations in the in-plane direction of the vibration portion of the beam.
As a result, the vibration element is particularly resistant to impact in the thickness direction of the vibration part.

[Application Example 4]
In the vibration element according to this application example, the first portion located on one side with respect to the through hole of the beam and the second portion located on the other side are provided symmetrically via the through hole. It is preferable.
Thereby, since a beam can bend with sufficient balance as a whole, the stress concentration to a beam can be controlled.

[Application Example 5]
In the vibration element according to this application example, it is preferable that the through hole is provided in 50% or more of the total length of the beam.
Thereby, temperature drift can be reduced more effectively while maintaining sufficient mechanical strength.

[Application Example 6]
In the resonator element according to this application example, it is preferable that the through hole is provided at least at both ends of the beam.
Since stress tends to concentrate at both ends of the beam, damage to the beam can be more effectively suppressed by providing through holes at both ends of the beam.

[Application Example 7]
In the vibration element according to this application example, the beam includes a first extension portion extending in a predetermined direction and a second extension portion extending in a direction different from the predetermined direction,
It is preferable that the through hole is formed in at least a part of the first extension part and at least a part of the second extension part.
Thereby, for example, in the case where the through-hole passes through two locations facing the thickness direction of the vibrating portion of the beam as in the above-described application example 2, the impact from any direction in the in-plane direction can be prevented. The beam also has excellent strength.

[Application Example 8]
In the vibration element of this application example, the vibration unit includes a base,
A detection arm extending along the first axis from the base;
A connecting arm extending along a second axis intersecting the first axis from the base;
A drive arm extending from the connection arm along the first axis,
It is preferable that the beam passes between the detection arm and the drive arm to connect the base portion and the support portion.
Thereby, a vibration element can be used as an angular velocity detection element.

[Application Example 9]
The vibrator of this application example includes the vibration element of this application example,
And a package containing the vibration element.
Thereby, a highly reliable vibrator is obtained.
[Application Example 10]
An electronic apparatus according to this application example includes the vibration element according to this application example.
As a result, a highly reliable electronic device can be obtained.
[Application Example 11]
A moving body according to this application example includes the vibration element according to this application example.
Thereby, a mobile body with high reliability is obtained.

1 is a plan view showing a first embodiment of a resonator element according to the invention. It is a top view which shows the electrode which the vibration element shown in FIG. 1 has. It is a top view (transmission figure) which shows the electrode which the vibration element shown in FIG. 1 has. FIG. 2 is a diagram for explaining the operation of the vibration element shown in FIG. 1. It is a perspective view which shows the mode of the unnecessary vibration which can generate | occur | produce in the vibration element shown in FIG. It is explanatory drawing for demonstrating the characteristic of the vibration element shown in FIG. It is a graph which shows the output temperature fluctuation width of the vibration element shown in FIG. It is a figure which shows the beam of the vibration element shown in FIG. 1, (a) is a perspective view, (b) is the sectional view on the AA line in the figure (a). It is a figure which shows the conventional beam, (a) is a perspective view, (b) is the BB sectional drawing in the figure (a). It is a perspective view which shows the stress which generate | occur | produces in the beam shown to FIG. 9 and FIG. 10 when the angular velocity of a Z-axis direction is added. It is a perspective view which shows the modification of the beam shown in FIG. It is a perspective view which shows the modification of the beam shown in FIG. It is a figure which shows the beam which the vibrator | oscillator concerning 2nd Embodiment of this invention has, (a) is a perspective view, (b) is CC sectional view taken on the line in the figure (a). (A) is a perspective view showing the stress generated in the beam when the angular velocity in the X-axis direction is applied, and (b) is a perspective view showing the stress generated in the beam when the angular velocity in the Y-axis direction is applied. It is a perspective view which shows the modification of the beam shown in FIG. It is a perspective view which shows the modification of the beam shown in FIG. It is a figure which shows the beam which the vibrator | oscillator concerning 3rd Embodiment of this invention has, (a) is a perspective view, (b) is the DD sectional view taken on the line in the figure (a). FIG. 4 is a diagram illustrating a preferred embodiment of the vibrator of the present invention, where (a) is a cross-sectional view and (b) is an upper surface. It is sectional drawing which shows suitable embodiment of a physical quantity sensor provided with the vibration element of this invention. FIG. 20 is a top view of the physical quantity sensor shown in FIG. 19. FIG. 20 is a top view of the physical quantity sensor shown in FIG. 19. It is a block diagram of a physical quantity detection device provided with a vibration element of the present invention. FIG. 11 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic device including the resonator element according to the invention is applied. It is a perspective view which shows the structure of the mobile telephone (PHS is also included) to which the electronic device provided with the vibration element of this invention is applied. It is a perspective view which shows the structure of the digital still camera to which the electronic device provided with the vibration element of this invention is applied. It is a perspective view which shows the structure of the motor vehicle to which the mobile body provided with the vibration element of this invention is applied.

Hereinafter, a resonator element, a vibrator, an electronic device, and a moving body of the present invention will be described in detail based on embodiments shown in the accompanying drawings.
1. Vibration Element <First Embodiment>
First, a first embodiment of the resonator element according to the invention will be described.

  FIG. 1 is a plan view showing a first embodiment of a resonator element according to the invention. FIG. 2 is a plan view showing electrodes of the vibration element shown in FIG. FIG. 3 is a plan view (transmission diagram) showing electrodes included in the vibration element shown in FIG. 1. FIG. 4 is a diagram for explaining the operation of the vibration element shown in FIG. 1. FIG. 5 is a perspective view showing a state of unnecessary vibration that can occur in the vibration element shown in FIG. 1. FIG. 6 is an explanatory diagram for explaining the characteristics of the vibration element shown in FIG. 1. FIG. 7 is a graph showing the output temperature fluctuation range of the vibration element shown in FIG. 1. 8A and 8B are diagrams showing a beam of the vibration element shown in FIG. 1, in which FIG. 8A is a perspective view, and FIG. 8B is a cross-sectional view taken along line AA in FIG. 9A and 9B are views showing a conventional beam, in which FIG. 9A is a perspective view, and FIG. 9B is a cross-sectional view taken along line BB in FIG. FIG. 10 is a perspective view showing stress generated in the beam shown in FIGS. 9 and 10 when an angular velocity in the Z-axis direction is applied. 11 and 12 are perspective views showing modifications of the beam shown in FIG. In the following, for convenience of explanation, the front side of the sheet of FIG. 1 is also referred to as “upper side” and the rear side of the sheet is also referred to as “lower side”. 1, 5, and 8 to 12, for convenience of explanation, illustration of electrodes is omitted. In the following, the direction along the X axis is also referred to as “X axis direction”, and the direction along the Y axis is also referred to as “Y axis direction”.

≪Basic structure of vibration element≫
A vibrating element 1 shown in FIG. 1 is used as an angular velocity detecting element (gyro element). Such a vibration element 1 has a piezoelectric substrate 2 and an electrode formed on the surface of the piezoelectric substrate 2.
-Piezoelectric substrate-
Examples of the constituent material of the piezoelectric substrate 2 include piezoelectric materials such as quartz, lithium tantalate, and lithium niobate. Among these, it is preferable to use quartz as a constituent material of the piezoelectric substrate 2. By using quartz, the resonator element 1 having excellent frequency temperature characteristics as compared with other materials can be obtained. Hereinafter, a case where the piezoelectric substrate 2 is made of quartz will be described.

  As shown in FIG. 1, the piezoelectric substrate 2 has a spread in an XY plane defined by a Y axis (mechanical axis, first axis) and an X axis (electric axis, second axis) which are crystal axes of the quartz crystal substrate. In addition, a plate shape having a thickness in the Z-axis (optical axis) direction is formed. That is, the piezoelectric substrate 2 is composed of a Z-cut quartz plate. The Z-axis preferably coincides with the thickness direction of the piezoelectric substrate 2, but is slightly (for example, less than about 15 °) with respect to the thickness direction from the viewpoint of reducing the frequency temperature change near normal temperature. You may tilt.

Such a piezoelectric substrate 2 includes the vibration unit 20, the first and second support units 251 and 252 disposed opposite to each other in the Y-axis direction via the vibration unit 20, the first support unit 251, and the vibration unit 20. First and third beams 261 and 263 to be connected, and second and fourth beams 262 and 264 to connect the second support portion 252 and the vibration portion 20 are provided.
The vibration unit 20 includes a base 21 located at the center, first and second detection arms 221 and 222 extending from the base 21 to both sides in the Y-axis direction, and extending from the base 21 to both sides in the X-axis direction. From the first and second connecting arms 231 and 232, the first and second drive arms 241 and 242 extending from the tip of the first connecting arm 231 to both sides in the Y-axis direction, and the tip of the second connecting arm 232 Third and fourth drive arms 243 and 244 extending on both sides in the Y-axis direction, and the base 21 is supported by the first and second support portions 251 and 252 by beams 261, 262, 263, and 263. .

  The first detection arm 221 extends from the base portion 21 in the + Y-axis direction, and a wide hammer head 2211 is provided at the tip portion thereof. On the other hand, the second detection arm 222 extends from the base portion 21 in the −Y-axis direction, and a wide hammer head 2221 is provided at the tip portion thereof. The first and second detection arms 221 and 222 are disposed symmetrically with respect to the XZ plane passing through the center of gravity G of the vibration element 1.

  By providing the hammer heads 2211 and 2221 on the first and second detection arms 221 and 222, the detection sensitivity of the angular velocity can be improved, and the lengths of the first and second detection arms 221 and 222 can be shortened. The hammer heads 2211 and 2221 may be provided as necessary and may be omitted. Moreover, you may form the bottomed groove | channel extended in the length direction in the upper surface and lower surface of the detection arms 221 and 222 as needed.

  The first connecting arm 231 extends from the base portion 21 in the + X axis direction. On the other hand, the second connecting arm 232 extends from the base portion 21 in the −X axis direction. The first and second connecting arms 231 and 232 are arranged symmetrically with respect to the YZ plane passing through the center of gravity G. In addition, you may provide the bottomed groove | channel extended in the length direction (X-axis direction) in the upper surface and lower surface of the 1st, 2nd connection arms 231,232.

  The first drive arm 241 extends in the + Y-axis direction from the distal end portion of the first connecting arm 231, and a wide hammer head 2411 is provided at the distal end portion. The second drive arm 242 extends in the −Y-axis direction from the distal end portion of the first connecting arm 231, and a wide hammer head 2421 is provided at the distal end portion. The third drive arm 243 extends in the + Y-axis direction from the distal end portion of the second connecting arm 232, and a wide hammer head 2431 is provided at the distal end portion. The fourth drive arm 244 extends in the −Y-axis direction from the distal end portion of the second connecting arm 232, and a wide hammer head 2441 is provided at the distal end portion. These four drive arms 241, 242, 243, 244 are arranged point-symmetrically with respect to the center of gravity G.

  By providing hammer heads 2411, 2421, 2431, and 2441 on the driving arms 241, 242, 243, and 244, the angular velocity detection sensitivity can be improved and the lengths of the driving arms 241, 242, 243, and 244 can be shortened. . The hammer heads 2411, 2421, 2431, and 2441 may be provided as necessary and may be omitted. Moreover, you may form the bottomed groove | channel extended in the length direction in the upper surface and lower surface of the drive arms 241, 242, 243, 244 as needed.

The first support portion 251 is located on the + Y axis direction side with respect to the base portion 21 and is arranged extending in the X axis direction. On the other hand, the second support portion 252 is located on the −Y axis direction side with respect to the base portion 21 and is disposed extending in the X axis direction. The first and second support portions 251 and 252 are arranged symmetrically with respect to the XZ plane passing through the center of gravity G.
The first beam 261 passes between the first detection arm 221 and the first drive arm 241 and connects the base portion 21 and the first support portion 251. The second beam 262 passes between the second detection arm 222 and the second drive arm 242 and connects the base portion 21 and the second support portion 252. The third beam 263 passes between the first detection arm 221 and the third drive arm 243 and connects the base portion 21 and the first support portion 251. The fourth beam 264 passes between the second detection arm 222 and the fourth drive arm 244 and connects the base portion 21 and the second support portion 252. These beams 261, 262, 263 and 264 are arranged point-symmetrically with respect to the center of gravity G.

  Each beam 261, 262, 263, 264 has a meandering portion (S-shaped portion) extending along the Y-axis direction while reciprocating along the X-axis direction, and is elastic in the X-axis direction and the Y-axis direction. have. Further, each beam 261, 262, 263, 264 has an elongated shape having a meandering portion, and therefore has elasticity in all directions. Therefore, even if an impact is applied from the outside, the impact can be absorbed by the beams 261, 262, 263, and 264, and detection noise caused by the impact can be reduced or suppressed.

-Electrode-
Electrodes are formed on the surface of the piezoelectric substrate 2.
As shown in FIGS. 2 and 3, the electrodes are the detection signal electrode 311, the detection signal terminal 312, the detection ground electrode 321, the detection ground terminal 322, the drive signal electrode 331, the drive signal terminal 332, and the drive. A ground electrode 341 and a drive ground terminal 342 are provided. 2 and 3, for convenience of explanation, the detection signal electrode 311 and the detection signal terminal 312, the detection ground electrode 321 and the detection ground terminal 322, the drive signal electrode 331 and the drive signal terminal 332, the drive ground electrode 341 and the drive ground are illustrated. The terminals 342 are illustrated with different hatchings. In addition, electrodes, wirings, and terminals formed on the side surface of the piezoelectric substrate 2 are shown by bold lines.

The detection signal electrode 311 is formed on the upper and lower surfaces (portions excluding the hammer heads 2211 and 2221) of the first and second detection arms 221 and 222. Such a detection signal electrode 311 is an electrode for detecting charges generated by the vibration when the detection vibrations of the first and second detection arms 221 and 222 are excited.
The detection signal terminal 312 is formed at the right end of the first and second support portions 251 and 252. The detection signal terminal 312 formed on the first support portion 251 is electrically connected to the detection signal electrode 311 formed on the first detection arm 221 via the detection signal wiring formed on the first beam 261. Yes. On the other hand, the detection signal terminal 312 formed on the second support portion 252 is electrically connected to the detection signal electrode 311 formed on the second detection arm 222 via the detection signal wiring formed on the second beam 262. Has been.

  The detection ground electrode 321 is formed on both side surfaces of the first and second detection arms 221 and 222. The detection ground electrodes 321 formed on both side surfaces of the first detection arm 221 are electrically connected via the hammer head 2211, and the detection ground electrodes formed on both side surfaces of the second detection arm 222. 321 is electrically connected via a hammer head 2221. Such a detection ground electrode 321 has a potential to be ground with respect to the detection signal electrode 311.

  The detection ground terminal 322 is formed at the center of the first and second support portions 251 and 252. The detection ground terminal 322 formed on the first support portion 251 is electrically connected to the detection ground electrode 321 formed on the first detection arm 221 via the detection ground wiring formed on the first beam 261. ing. On the other hand, the detection ground terminal 322 formed on the second support portion 252 is electrically connected to the detection ground electrode 321 formed on the second detection arm 222 via the detection ground wiring formed on the second beam 262. It is connected.

  Thus, by arranging the detection signal electrode 311, the detection signal terminal 312, the detection ground electrode 321, and the detection ground terminal 322, the detection vibration generated in the first detection arm 221 is applied to the first detection arm 221. It appears as a charge between the formed detection signal electrode 311 and the detection ground electrode 321, and can be taken out as a signal from the detection signal terminal 312 and the detection ground terminal 322 formed in the first support portion 251. In addition, the detection vibration generated in the second detection arm 222 appears as a charge between the detection signal electrode 311 formed on the second detection arm 222 and the detection ground electrode 321, and the detection vibration formed on the second support portion 252. It can be taken out as a signal from the signal terminal 312 and the detection ground terminal 322.

The drive signal electrode 331 is formed on the upper and lower surfaces (portions excluding the hammer heads 2411 and 2421) of the first and second drive arms 241 and 242. Further, the drive signal electrode 331 is formed on both side surfaces of the third and fourth drive arms 243 and 244. The drive signal electrodes 331 formed on both side surfaces of the third drive arm 243 are electrically connected via the hammer head 2431, and the drive signal electrodes formed on both side surfaces of the fourth drive arm 244. 331 is electrically connected via a hammer head 2441. Such a drive signal electrode 331 is an electrode for exciting drive vibrations of the first, second, third, and fourth drive arms 241, 242, 243, and 244.
The drive signal terminal 332 is formed at the left end portion of the second support portion 252. The drive signal terminal 332 is connected to the drive signal electrode 331 formed on the first, second, third, and fourth drive arms 241, 242, 243, and 244 via the drive signal wiring formed on the fourth beam 264. Electrically connected.

  The drive ground electrode 341 is formed on the upper and lower surfaces (portions excluding the hammer heads 2431 and 2441) of the third and fourth drive arms 243 and 244. Further, the drive ground electrode 341 is formed on both side surfaces of the first and second drive arms 241 and 242. The drive ground electrodes 341 formed on both side surfaces of the first drive arm 241 are electrically connected via the hammer head 2411, and the drive ground electrodes formed on both side surfaces of the second drive arm 242. 341 is electrically connected via a hammer head 2421. Such a drive ground electrode 341 has a potential to be ground with respect to the drive signal electrode 331.

The drive ground terminal 342 is formed at the left end of the first support portion 251. The drive ground terminal 342 is connected to the drive ground electrode 341 formed on the first, second, third, and fourth drive arms 241, 242, 243, and 244 via the drive ground wiring formed on the third beam 263. Electrically connected.
By arranging the drive signal electrode 331, the drive signal terminal 332, the drive ground electrode 341, and the drive ground terminal 342 in this way, the drive signal is applied between the drive signal terminal 332 and the drive ground terminal 342, so that the first An electric field is generated between the drive signal electrode 331 and the drive ground electrode 341 formed on the first, second, third, and fourth drive arms 241, 242, 243, 244, and the drive arms 241, 242, 243, 244 can be driven to vibrate.
The configuration of the electrode as described above is not particularly limited as long as it has conductivity. For example, Ni (nickel), Au (metal) layer such as Cr (chromium), W (tungsten), etc. (Gold), Ag (silver), Cu (copper), etc. can be comprised by the metal film which laminated | stacked each film.

≪Drive of vibration element≫
Next, driving of the vibration element 1 will be described.
An electric field is generated between the drive signal electrode 331 and the drive ground electrode 341 by applying a voltage (alternating voltage) between the drive signal terminal 332 and the drive ground terminal 342 in a state where no angular velocity is applied to the vibration element 1. Then, as shown in FIG. 4A, the drive arms 241, 242, 243, and 244 perform bending vibration in the direction indicated by the arrow A. At this time, the first and second drive arms 241 and 242 and the third and fourth drive arms 243 and 244 perform plane-symmetric vibration with respect to the YZ plane passing through the center of gravity G of the vibration element 1. The first and second detection arms 221 and 222 and the first and second connection arms 231 and 232 hardly vibrate.

  When an angular velocity ω around the Z-axis is applied to the vibration element 1 in a state where this drive vibration is being performed, a detection vibration as shown in FIG. 4B is excited. Specifically, Coriolis force in the direction of arrow B acts on the drive arms 241, 242, 243, 244 and the first and second connecting arms 231, 232, and new vibrations are excited. This vibration in the direction of arrow B is a vibration in the circumferential direction with respect to the center of gravity G. At the same time, detection vibration in the direction of arrow C is excited in the first and second detection arms 221 and 222 in response to the vibration of arrow B. The electric charges generated in the first and second detection arms 221 and 222 by this vibration are taken out as signals from the detection signal electrode 311 and the detection ground electrode 321, and the angular velocity is obtained based on this signal.

Next, unnecessary vibration that occurs when the vibration element 1 is driven will be described.
When the vibration element 1 is driven as described above, a slight unnecessary vibration is generated along with the vibration in the driving mode. There are various vibration modes for this unnecessary vibration, but the inventors have shown that the following two vibration modes (y1 mode vibration and y2 mode vibration) greatly affect the temperature drift in the characteristics of the vibration element 1. Focused on having. Therefore, with reference to FIGS. 5 and 6, the vibrations in the y1 mode and the y2 mode and the influence of the vibrations on the characteristics of the vibration element 1 will be described.

  First, the y1 mode will be described. As shown in FIG. 5A, the y1 mode is a vibration mode in which the base 21 and the drive arms 241, 242, 243, 244 move to the same side in the Y-axis direction. Thus, in the y1 mode, the base 21 and the drive arms 241, 242, 243, 244 move in the same direction in the Y-axis direction, so that the vibration of the base 21 and the vibrations of the drive arms 241, 242, 243, 244 are confined. This will affect the vibration characteristics of the vibration element 1, particularly the temperature drift which is a characteristic variation depending on the temperature. More specifically, as indicated by a curve L2 shown in FIG. 6A, the output characteristics of the vibration element 1 fluctuate with changes in temperature, and the fluctuation range of output increases. That is, the temperature drift becomes large. If no temperature drift occurs, a characteristic with little fluctuation is obtained as in the curve L1.

Next, the y2 mode will be described. As shown in FIG. 5B, the y2 mode is a vibration mode in which the base 21 and the drive arms 241, 242, 243, 244 move to the opposite side in the Y-axis direction. Thus, in the y2 mode, the base 21 and the drive arms 241, 242, 243, 244 move to the opposite side in the Y-axis direction, so the vibration of the base 21 and the vibration of the drive arms 241, 242, 243, 244 cancel each other. And thereby confine the vibration. Therefore, the y2 mode hardly affects the vibration characteristics of the vibration element 1, particularly the temperature drift which is a characteristic variation depending on the temperature.
Next, y1 mode and y2 mode excitation will be described. Here, the y1 mode vibration frequency will be described as y1 mode vibration frequency fy1, the y2 mode vibration frequency as y2 mode vibration frequency fy2, and the resonance frequencies of the drive arms 241, 243, 242, and 244 as drive vibration frequencies fd.

  As shown in FIG. 6B, the difference | fd−fy2 | between the y2 mode vibration frequency fy2 and the drive vibration frequency fd is larger than the difference | fd−fy1 | between the y1 mode vibration frequency fy1 and the drive vibration frequency fd. In this case, the y1 mode vibration is likely to be excited. In contrast, as shown in FIG. 6C, the difference | fd−fy2 | between the y2 mode vibration frequency fy2 and the drive vibration frequency fd is the difference | fd− between the y1 mode vibration frequency fy1 and the drive vibration frequency fd. If it is smaller than fy1 |, the y2 mode vibration is likely to be excited, which suppresses the excitation of the y1 mode vibration and makes it difficult to excite.

  FIG. 7 shows the relationship between the difference | fd−fy2 | between the y2 mode vibration frequency fy2 and the drive vibration frequency fd and the difference | fd−fy1 | between the y1 mode vibration frequency fy1 and the drive vibration frequency fd. It is a graph which shows the influence which it has with respect to the temperature fluctuation range. As shown in FIG. 7, | fd−fy2 | / | fd−fy1 | = 1, ie, | fd−fy2 | = | fd−fy1 | It can be seen that the temperature fluctuation range of the output of the vibration element 1 is extremely large on the side where the temperature fluctuation range of the output of 1 is extremely small and the number is large. Thus, by setting the relationship between the drive vibration frequency fd, the y1 mode vibration frequency fy1 and the y2 mode vibration frequency fy2 to | fd−fy1 |> | fd−fy2 |, the y1 mode vibration is hardly excited. Thus, the influence of the output characteristics of the vibration element 1 on the temperature drift can be suppressed.

  The inventors have made the beams 261, 262, 263, 264 thinner and thinner as one method for making | fd−fy 1 |> | fd−fy 2 | It was found that the bending rigidity of H.264 may be reduced. However, simply reducing the bending rigidity of each of the beams 261, 262, 263, and 264 leads to insufficient strength of the beams 261, 262, 263, and 264. When a direction impact (acceleration) is applied, there is a high possibility that the beams 261, 262, 263, and 264 are damaged. Therefore, the vibration element 1 is characterized by the shapes of the beams 261, 262, 263, and 263 so that the y1 mode vibration is not easily excited and sufficient mechanical strength can be exhibited.

≪Beam shape≫
Hereinafter, the shapes of the beams 261, 262, 263, and 264 will be described in detail. However, since the beams 261, 262, 263, and 264 have the same configuration, the beam 261 will be described as a representative in the following. The description of H.263, H.264 is omitted.
As shown in FIGS. 8A and 8B, the beam 261 is formed with through holes 261C penetrating through both side surfaces (two locations facing the in-plane direction of the vibrating portion 20) over almost the entire length thereof. Yes. Therefore, the beam 261 is disposed to face the upper beam portion 261A located on the + Z-axis side and the upper beam portion 261A across the gap, and the lower beam portion (the second beam portion located on the −Z-axis side (second portion). It can be said that it is comprised with 261B. The upper beam portion 261A and the lower beam portion 261B are provided in a vertical contrast via the through hole 261C. That is, the cross-sectional shapes of the upper beam portion 261A and the lower beam portion 261B are substantially equal. Further, the thickness d of the through hole 261C is not particularly limited, but is preferably about ¼ or more and ½ or less of the thickness D of the beam 261, for example.
By configuring the beam 261 as described above, for example, the cross-sectional secondary moment Iz around the Z-axis is selectively reduced as compared with the conventional beam 261 ′ shown in FIGS. 9A and 9B. be able to. Therefore, the beam 261 has a small bending rigidity.

Furthermore, with the beam 261 having such a configuration, when an impact (acceleration) in the Z-axis direction is applied to the vibration element 1, a shear stress is less likely to be applied than in the conventional beam 261 ′. Specifically, when the base 21 is displaced in the Z-axis direction with respect to the support portions 251 and 252 by the impact, in the conventional beam 261 ′, the beam 261 ′ is twisted as shown in FIG. Shear stress occurs. On the other hand, according to the beam 261, as shown in FIG. 10B, each of the upper beam portion 261A and the lower beam portion 261B substantially bends in the thickness direction (Z-axis direction). Therefore, it is difficult for shear stress to occur. For this reason, the beam 261 is not easily broken even if it receives an impact in the Z-axis direction. Therefore, the vibration element 1 has excellent mechanical strength (impact resistance).
As described above, according to the beam 261, the vibration element 1 that can reduce temperature drift and has sufficient mechanical strength is obtained.

In particular, since the upper beam portion 261A and the lower beam portion 261B are provided in contrast to each other via the through hole 261C, the upper beam portion 261A and the lower beam portion 261B bend in a well-balanced manner, and stress concentration on the beam 261 is concentrated. It is effectively suppressed. Therefore, higher mechanical strength can be exhibited.
As shown in FIG. 8A, in this embodiment, the through hole 261C is formed over almost the entire length of the beam 261. However, the present invention is not limited to this, and the through hole 261C is formed as shown in FIG. ), The beam 261 may be formed only on a part of the entire length. However, the through hole 261C is preferably formed over 50% or more of the total length of the beam 261, more preferably 70% or more, and even more preferably 90% or more. Thereby, the effect mentioned above can be exhibited effectively.

  Further, as shown in FIG. 11B, the through-hole 261C may be provided intermittently in a plurality of portions along the entire length of the beam 261. In particular, as shown in FIG. 11B, the through-hole 261C is formed in each of a portion extending in the X-axis direction and a portion extending in the Y-axis direction of the beam 261. preferable. Specifically, the beam 261 includes an extending portion 2611 extending from the base portion 21 in the + X-axis direction, an extending portion 2612 extending in the + Y-axis direction from the distal end portion of the extending portion 2611, and an extending portion 2612. An extending portion 2613 extending in the −X-axis direction from the distal end portion of the first extending portion 2613, and an extending portion 2614 extending in the + Y-axis direction from the distal end portion of the extending portion 2613 and connected to the first support portion 251. Among these extending portions, at least a part of at least one of the extending portions (first extending portions) 2611 and 2613 and at least one of the extending portions (second extending portions) 2612 and 2614 It is preferable that a through-hole 261C is formed at least partially. As a result, even when an impact in the Z-axis direction is applied, it is difficult for shear stress to be applied to the beam 261, and the above effects can be exhibited more effectively.

  In addition, as shown in FIG. 12A, the beam 261 preferably has through holes 261C formed at least at both ends T1 and T2. When receiving an impact (acceleration) in the Z-axis direction, particularly large stress is applied to both ends T1, T2, that is, the vicinity of the connection portion with the support portion 251 and the vicinity of the connection portion with the base portion 21 in the beam 261. By forming the through holes 261C in the portions T1 and T2, the above effects can be exhibited more effectively.

  In the present embodiment, the entire area of the through-hole 261C is accommodated inside the beam 261. However, the present invention is not limited to this. For example, as shown in FIG. The other end may enter the base 21. As described above, when a shock (acceleration) in the Z-axis direction is applied, particularly large stress is applied in the vicinity of the connection portion with the support portion 251 and the connection portion with the base portion 21. The above effects can be exhibited more effectively.

  Moreover, it is preferable that the through-hole 261C is formed in each of the portion extending in the X-axis direction and the portion extending in the Y-axis direction of the beam 261. Specifically, as shown in FIG. 13, the beam 261 includes an extending portion 2611 extending from the base portion 21 in the + X-axis direction and an extending portion extending from the distal end portion of the extending portion 2611 in the + Y-axis direction. 2612, an extending portion 2613 extending in the −X-axis direction from the distal end portion of the extending portion 2612, and extending in the + Y-axis direction from the distal end portion of the extending portion 2613, and connected to the first support portion 251. An extension part 2614, and of these extension parts, at least a part of at least one of extension parts (first extension parts) 2611 and 2613 and an extension part (second extension part). It is preferable that a through hole 261 </ b> C is formed in at least a part of at least one of 2612 and 2614. As a result, even when an impact in the Z-axis direction is applied, it is difficult for shear stress to be applied to the beam 261, and the above effects can be exhibited more effectively.

Second Embodiment
Next, a second embodiment of the resonator element according to the invention will be described.
FIGS. 13A and 13B are diagrams showing beams included in the vibrator according to the second embodiment of the present invention, in which FIG. 13A is a perspective view and FIG. 13B is a cross-sectional view taken along the line CC in FIG. . 14A is a perspective view showing the stress generated in the beam when an angular velocity in the X-axis direction is applied, and FIG. 14B is a perspective view showing the stress generated in the beam when an angular velocity in the Y-axis direction is applied. FIG. 15 and 16 are perspective views showing modifications of the beam shown in FIG. In FIG. 13 to FIG. 16, illustration of electrodes is omitted for convenience of explanation.

Hereinafter, the second embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The second embodiment is the same as the first embodiment described above except that the configuration of each beam is different. In FIG. 14, the same reference numerals are given to the same components as those in the above-described embodiment. Hereinafter, the shapes of the beams 261, 262, 263, and 264 will be described in detail. Since the beams 261, 262, 263, and 264 have the same configuration, the beam 261 will be described below as a representative. Description of the beams 262, 263, and 264 is omitted.

  As shown in FIGS. 13A and 13B, the beam 261 is formed with a through hole 261F penetrating the upper and lower surfaces over almost the entire length thereof. Therefore, the beam 261 is disposed to face the inner beam portion 261D located on the −X axis side and the inner beam portion 261D across the gap, and the outer beam portion (second portion) located on the + X axis side. It can be said that it is composed of H.261E. The inner beam portion 261D and the outer beam portion 261E are provided in contrast to the left and right via the through hole 261F. That is, the cross-sectional shapes of the inner beam portion 261D and the outer beam portion 261E are substantially equal. Further, the width w of the through hole 261F is not particularly limited, but is preferably about ¼ or more and ½ or less of the width W of the beam 261, for example.

By configuring the beam 261 as described above, for example, the cross-sectional secondary moment Iz around the Z-axis is selectively reduced as compared with the conventional beam 261 ′ shown in FIGS. 9A and 9B. be able to. Therefore, the beam 261 has a small bending rigidity.
Furthermore, by configuring the beam 261 in such a configuration, when an impact (acceleration) in the in-plane direction (X-axis direction or Y-axis direction) of the XY plane is applied to the vibration element 1, the conventional beam 261 is used. More difficult to apply shear stress than '. Specifically, according to the beam 261, even if the base 21 is displaced in the X-axis direction with respect to the support portions 251 and 252 by the impact, as shown in FIG. Since each of the portions (extension portions 2612 and 2614) extending in the Y-axis direction of the beam portion 261D and the outer beam portion 261E is bent in the X-axis direction, shear stress is hardly generated. Further, even if the base portion 21 is displaced in the Y-axis direction with respect to the support portions 251 and 252 due to the impact, as shown in FIG. 14B, substantially the X of the inner beam portion 261D and the outer beam portion 261E. Since each of the portions extending in the axial direction (extending portions 2611 and 2613) is only bent in the Y-axis direction, shear stress is unlikely to occur. Therefore, the beam 261 is not easily broken even when receiving an impact in the in-plane direction within the XY plane. Therefore, the vibration element 1 has excellent mechanical strength (impact resistance).
As described above, according to the beam 261, the vibration element 1 that can reduce temperature drift and has sufficient mechanical strength is obtained.

In particular, since the inner beam portion 261D and the outer beam portion 261E are provided in contrast via the through hole 261F, the inner beam portion 261D and the outer beam portion 261E bend in a well-balanced manner, and stress concentration on the beam 261 is effectively performed. Is suppressed. Therefore, higher mechanical strength can be exhibited.
As shown in FIG. 13A, in the present embodiment, the through hole 261F is formed over almost the entire length of the beam 261. However, the present invention is not limited to this. ), The beam 261 may be formed only on a part of the entire length. However, the through hole 261F is preferably formed over 50% or more of the total length of the beam 261, more preferably 70% or more, and even more preferably 90% or more. Thereby, the effect mentioned above can be exhibited effectively.

  Moreover, as shown in FIG.15 (b), the through-hole 261F may be divided into several and provided intermittently in the full length of the beam 261. FIG. In particular, as shown in FIG. 15B, the through-hole 261F is formed in each of the portion extending in the X-axis direction and the portion extending in the Y-axis direction of the beam 261. preferable. Specifically, at least a part of at least one of the extension parts (first extension parts) 2611 and 2613 and at least a part of at least one of the extension parts (second extension parts) 2612 and 2614, It is preferable that the through hole 261F is formed. As a result, both when an impact in the X-axis direction is applied and when an impact in the Y-axis direction is applied, it is difficult for shear stress to be applied to the beam 261, and the above-described effects can be exhibited more effectively. .

  In addition, as shown in FIG. 16A, the beam 261 preferably has through holes 261F formed at least at both ends T1 and T2. When receiving an impact (acceleration) in the in-plane direction of the XY plane, particularly large stress is applied to both ends T1, T2, that is, the vicinity of the connection portion with the support portion 251 and the vicinity of the connection portion with the base portion 21 in the beam 261. By forming the through holes 261F at both end portions T1 and T2, the above effects can be exhibited more effectively.

  In the present embodiment, the entire area of the through hole 261F is accommodated inside the beam 261. However, the present invention is not limited to this. For example, as shown in FIG. The other end may enter the base 21. As described above, when a shock (acceleration) in the in-plane direction of the XY plane is received, particularly large stress is applied in the vicinity of the connection portion with the support portion 251 and the connection portion with the base portion 21. By doing so, the above effects can be more effectively exhibited.

<Third Embodiment>
Next, a third embodiment of the resonator element according to the invention will be described.
FIGS. 17A and 17B are diagrams showing a beam included in the vibrator according to the third embodiment of the present invention, in which FIG. 17A is a perspective view and FIG. 17B is a cross-sectional view taken along the line DD in FIG. . In FIG. 17, for convenience of explanation, illustration of electrodes is omitted.

Hereinafter, the third embodiment will be described with a focus on differences from the above-described embodiment, and description of similar matters will be omitted.
The second embodiment is the same as the first embodiment described above except that the configuration of each beam is different. In FIG. 17, the same reference numerals are given to the same configurations as those in the above-described embodiment. Hereinafter, the shapes of the beams 261, 262, 263, and 264 will be described in detail. Since the beams 261, 262, 263, and 264 have the same configuration, the beam 261 will be described below as a representative. Description of the beams 262, 263, and 264 is omitted.

  As shown in FIGS. 17A and 17B, the beam 261 is formed with a through-hole 261I that is inclined in an oblique direction (a direction inclined with respect to the Z-axis) over almost the entire length thereof. Therefore, the beam 261 is disposed to face the inner beam portion 261G located on the −X axis side and the inner beam portion 261G across the gap, and the outer beam portion (second portion) located on the + X axis side. It can be said that it is composed of 261H. According to the beam 261 having such a configuration, the effects of the first embodiment and the effects of the second embodiment described above can be exhibited. That is, the vibration element 1 is resistant to both an impact in the Z-axis direction and an impact in the in-plane direction of the XY plane.

2. Next, the vibrator 10 using the vibration element 1 will be described.
18A and 18B are diagrams showing a preferred embodiment of the vibrator of the present invention. FIG. 18A is a cross-sectional view, and FIG. 18B is a top view.
As illustrated in FIGS. 18A and 18B, the vibrator 10 includes the vibration element 1 and a package 8 that houses the vibration element 1.

  The package 8 includes a box-shaped base 81 having a concave portion 811 and a plate-shaped lid 82 that blocks the opening of the concave portion 811 and is joined to the base 81. The vibration element 1 is housed in a housing space formed by closing the recess 811 with the lid 82. The housing space may be in a reduced pressure (vacuum) state or may be filled with an inert gas such as nitrogen, helium, or argon.

  The constituent material of the base 81 is not particularly limited, and various ceramics such as aluminum oxide and various glass materials can be used. Further, the constituent material of the lid 82 is not particularly limited, but may be a member whose linear expansion coefficient approximates that of the constituent material of the base 81. For example, in the case where the constituent material of the base 81 is ceramic as described above, it is preferable to use an alloy such as Kovar. In addition, the joining method of the base 81 and the lid 82 is not specifically limited, For example, it can join via an adhesive material or a brazing material.

  Connection terminals 831, 832, 833, 834, 835, and 836 are formed on the bottom surface of the recess 811. Each of the connection terminals 831 to 836 is drawn to the lower surface of the base 81 (the outer peripheral surface of the package 8) by a through electrode (not shown) formed on the base 81. The structure of the connection terminals 831 to 836 is not particularly limited as long as it has conductivity. For example, Ni (nickel) or Au is used as a metallization layer (underlayer) such as Cr (chromium) or W (tungsten). (Gold), Ag (silver), Cu (copper), etc. can be comprised by the metal film which laminated | stacked each film.

In the vibration element 1, the first support portion 251 is fixed to the bottom surface of the concave portion 811 by the conductive adhesives 861, 862, and 863, and the second support portion 252 is formed of the concave portion 811 by the conductive adhesive materials 864, 865, and 866. It is fixed to the bottom. In addition, one detection signal terminal 312 and the connection terminal 831 are electrically connected by the conductive adhesive 861, and one detection ground terminal 322 and the connection terminal 832 are electrically connected by the conductive adhesive 862. The drive ground terminal 342 and the connection terminal 833 are electrically connected by the conductive adhesive 863, and the other detection signal terminal 312 and the connection terminal 834 are electrically connected by the conductive adhesive 864. The other detection ground terminal 322 and the connection terminal 835 are electrically connected by the conductive adhesive 865, and the drive signal terminal 332 and the connection terminal 836 are electrically connected by the conductive adhesive 866.
The conductive adhesives 861 to 866 are not particularly limited as long as they have electrical conductivity and adhesiveness. For example, silver particles are bonded to adhesives such as silicone, epoxy, acrylic, polyimide, and bismaleimide. What disperse | distributed conductive fillers, such as these, can be used.

3. Physical Quantity Sensor Next, the physical quantity sensor 100 using the vibration element 1 will be described.
FIG. 19 is a cross-sectional view illustrating a preferred embodiment of a physical quantity sensor including the vibration element of the present invention. 20 and 21 are top views of the physical quantity sensor shown in FIG. 19, respectively. In FIG. 16, for convenience of explanation, illustration of the lid and the vibration element is omitted.

As shown in FIGS. 19, 20, and 21, the physical quantity sensor 100 includes the vibration element 1, a package 8 that houses the vibration element 1, and an IC chip 9.
As shown in FIG. 19, the package 8 includes a box-shaped base 81 having a concave portion 811 and a plate-shaped lid 82 that blocks the opening of the concave portion 811 and is joined to the base 81. The resonator element 1 and the IC chip 9 are housed in a housing space formed by closing the recess 811 with the lid 82. The housing space may be in a reduced pressure (vacuum) state or may be filled with an inert gas such as nitrogen, helium, or argon.

  The recess 811 includes a first recess 811a that opens to the top surface of the base 81, a second recess 811b that opens to the center of the bottom surface of the first recess 811a, and a third recess that opens to the center of the bottom surface of the second recess 811b. 811c. Connection wires 871, 872, 873, 874, 875, and 876 are formed from the bottom surface of the first recess 811a to the bottom surface of the second recess 811b.

  As shown in FIG. 20, in the vibration element 1, the first support portion 251 is fixed to the bottom surface of the first recess 811 a by the conductive adhesives 861, 862, and 863, and the second support portion 252 is the conductive adhesive material. 864, 865, and 866 are fixed to the bottom surface of the first recess 811a. Then, one detection signal terminal 312 and the connection wiring 871 are electrically connected by the conductive adhesive 861, and one detection ground terminal 322 and the connection wiring 872 are electrically connected by the conductive adhesive 862. The drive ground terminal 342 and the connection wiring 873 are electrically connected by the conductive adhesive 863, and the other detection signal terminal 312 and the connection wiring 874 are electrically connected by the conductive adhesive 864. The other detection ground terminal 322 and the connection wiring 875 are electrically connected by the conductive adhesive 865, and the drive signal terminal 332 and the connection wiring 876 are electrically connected by the conductive adhesive 866.

As shown in FIG. 21, the IC chip 9 is fixed to the bottom surface of the third recess 811c with a brazing material or the like. The IC chip 9 is electrically connected to each connection wiring 871, 872, 873, 874, 875, 876 by a conductive wire. Accordingly, each of the two detection signal terminals 312, the two detection ground terminals 322, the drive signal terminal 332, and the drive ground terminal 342 is in a state of being electrically connected to the IC chip 9. The IC chip 9 has a drive circuit for driving and vibrating the vibration element 1 and a detection circuit for detecting a detection vibration generated in the vibration element 1 when an angular velocity is applied.
In the present embodiment, the IC chip 9 is provided inside the package 8, but the IC chip 9 may be provided outside the package 8.

4). Physical Quantity Detection Device Next, a physical quantity detection device 1000 using the vibration element 1 will be described.
FIG. 22 is a block diagram of a physical quantity detection device including the vibration element of the present invention.
As illustrated in FIG. 22, the physical quantity detection device 1000 includes the vibration element 1, a drive circuit 71, and a detection circuit 72. The drive circuit 71 and the detection circuit 72 can be incorporated into the IC chip 9 as described above, for example.

The drive circuit 71 functions as a drive circuit, and includes an I / V conversion circuit (current / voltage conversion circuit) 711, an AC amplification circuit 712, and an amplitude adjustment circuit 713. Such a drive circuit 71 is a circuit for supplying a drive signal to the drive signal electrode 331 formed in the vibration element 1.
When the vibration element 1 vibrates, an alternating current based on the piezoelectric effect is output from the drive signal electrode 331 formed on the vibration element 1 and input to the I / V conversion circuit 711 via the drive signal terminal 332. The I / V conversion circuit 711 converts the input alternating current into an alternating voltage signal having the same frequency as the vibration frequency of the vibration element 1 and outputs it. The AC voltage signal output from the I / V conversion circuit 711 is input to the AC amplifier circuit 712, and the AC amplifier circuit 712 amplifies and outputs the input AC voltage signal.

  The AC voltage signal output from the AC amplifier circuit 712 is input to the amplitude adjustment circuit 713. The amplitude adjustment circuit 713 controls the gain so that the amplitude of the input AC voltage signal is held at a constant value, and the AC voltage signal after gain control is supplied via the drive signal terminal 332 formed in the vibration element 1. Output to the drive signal electrode 331. The vibration element 1 vibrates by an AC voltage signal (drive signal) input to the drive signal electrode 331.

  The detection circuit 72 functions as a detection circuit, and includes charge amplifier circuits 721 and 722, a differential amplifier circuit 723, an AC amplifier circuit 724, a synchronous detection circuit 725, a smoothing circuit 726, a variable amplifier circuit 727, and a filter. A circuit 728. The detection circuit 72 includes a first detection signal generated at the detection signal electrode 311 formed on the first detection arm 221 of the vibration element 1 and a second detection signal generated at the detection signal electrode 311 formed on the second detection arm 222. Are differentially amplified to generate a differential amplification signal, and a predetermined physical quantity is detected based on the differential amplification signal.

  In the charge amplifier circuits 721 and 722, detection signals (AC currents) of opposite phases detected by the detection signal electrodes 311 formed on the first and second detection arms 221 and 222 of the vibration element 1 are detected signal terminals. It is input via 312. For example, the charge amplifier circuit 721 receives the first detection signal detected by the detection signal electrode 311 formed on the first detection arm 221, and the charge amplifier circuit 722 detects the detection signal formed on the second detection arm 222. A second detection signal detected by the electrode 311 is input. Then, the charge amplifier circuits 721 and 722 convert the input detection signal (alternating current) into an alternating voltage signal centered on the reference voltage Vref.

  The differential amplifier circuit 723 differentially amplifies the output signal of the charge amplifier circuit 721 and the output signal of the charge amplifier circuit 722 to generate a differential amplified signal. The output signal (differential amplified signal) of the differential amplifier circuit 723 is further amplified by the AC amplifier circuit 724. The synchronous detection circuit 725 functions as a detection circuit, and extracts an angular velocity component by synchronously detecting the output signal of the AC amplification circuit 724 based on the AC voltage signal output from the AC amplification circuit 712 of the drive circuit 71.

  The angular velocity component signal extracted by the synchronous detection circuit 725 is smoothed into a DC voltage signal by the smoothing circuit 726 and input to the variable amplification circuit 727. The variable amplifier circuit 727 amplifies (or attenuates) the output signal (DC voltage signal) of the smoothing circuit 726 with a set amplification factor (or attenuation factor) to change the angular velocity sensitivity. The signal amplified (or attenuated) by the variable amplifier circuit 727 is input to the filter circuit 728.

The filter circuit 728 removes a high-frequency noise component from the output signal of the variable amplifier circuit 727 (more precisely, attenuates to a predetermined level or less), and generates a detection signal having a polarity and a voltage level corresponding to the direction and magnitude of the angular velocity. To do. This detection signal is output to the outside from an external output terminal (not shown).
According to such a physical quantity detection apparatus 1000, as described above, the first detection signal generated in the detection signal electrode 311 formed in the first detection arm 221 and the detection signal electrode 311 formed in the second detection arm 222 are detected. The generated second detection signal is differentially amplified to generate a differential amplification signal, and a predetermined physical quantity can be detected based on the differential amplification signal.

5. Electronic Device Next, an electronic device to which the vibration element 1 is applied will be described in detail with reference to FIGS.
FIG. 23 is a perspective view illustrating a configuration of a mobile (or notebook) personal computer to which an electronic device including the resonator element according to the invention is applied.

  In this figure, a personal computer 1100 includes a main body portion 1104 provided with a keyboard 1102 and a display unit 1106 provided with a display portion 1108. The display unit 1106 is rotated with respect to the main body portion 1104 via a hinge structure portion. It is supported movably. Such a personal computer 1100 incorporates a vibration element 1 that functions as an angular velocity detection means (gyro sensor).

FIG. 24 is a perspective view illustrating a configuration of a mobile phone (including PHS) to which an electronic device including the resonator element according to the invention is applied.
In this figure, a cellular phone 1200 includes a plurality of operation buttons 1202, an earpiece 1204, and a mouthpiece 1206, and a display unit 1208 is disposed between the operation buttons 1202 and the earpiece 1204. Such a cellular phone 1200 incorporates a vibration element 1 that functions as an angular velocity detection means (gyro sensor).

  FIG. 25 is a perspective view illustrating a configuration of a digital still camera to which an electronic device including the resonator element according to the invention is applied. In this figure, connection with an external device is also simply shown. Here, an ordinary camera sensitizes a silver halide photographic film with a light image of a subject, whereas a digital still camera 1300 photoelectrically converts a light image of a subject with an imaging device such as a CCD (Charge Coupled Device). An imaging signal (image signal) is generated.

A display unit is provided on the back of a case (body) 1302 in the digital still camera 1300, and is configured to perform display based on an imaging signal from the CCD. The display unit 1310 displays a subject as an electronic image. Function as.
A light receiving unit 1304 including an optical lens (imaging optical system), a CCD, and the like is provided on the front side (the back side in the drawing) of the case 1302.
When the photographer confirms the subject image displayed on the display unit and presses the shutter button 1306, the CCD image pickup signal at that time is transferred and stored in the memory 1308.

In the digital still camera 1300, a video signal output terminal 1312 and an input / output terminal 1314 for data communication are provided on the side surface of the case 1302. As shown in the figure, a television monitor 1430 is connected to the video signal output terminal 1312 and a personal computer 1440 is connected to the input / output terminal 1314 for data communication as necessary. Further, the imaging signal stored in the memory 1308 is output to the television monitor 1430 or the personal computer 1440 by a predetermined operation.
Such a digital still camera 1300 incorporates a vibration element 1 that functions as an angular velocity detection means (gyro sensor).

  Note that the electronic device including the vibration element of the present invention includes, for example, an ink jet type ejection device (for example, a personal computer (mobile personal computer) in FIG. 23, a mobile phone in FIG. 24, and a digital still camera in FIG. 25). Inkjet printers), laptop personal computers, televisions, video cameras, video tape recorders, car navigation devices, pagers, electronic notebooks (including those with communication functions), electronic dictionaries, calculators, electronic game devices, word processors, workstations, televisions Telephone, crime prevention TV monitor, electronic binoculars, POS terminal, medical equipment (for example, electronic thermometer, blood pressure monitor, blood glucose meter, electrocardiogram measuring device, ultrasonic diagnostic device, electronic endoscope), fish detector, various measuring devices, instruments Class (eg, vehicle, aircraft) Gauges of a ship), can be applied to a flight simulator or the like.

6). Next, a moving body to which the vibration element shown in FIG. 1 is applied will be described in detail with reference to FIG.
FIG. 26 is a perspective view illustrating a configuration of an automobile to which a moving body including the vibration element according to the invention is applied.

  The automobile 1500 has a built-in vibration element 1 that functions as an angular velocity detection means (gyro sensor), and the posture of the vehicle body 1501 can be detected by the vibration element 1. The detection signal of the vibration element 1 is supplied to the vehicle body posture control device 1502, and the vehicle body posture control device 1502 detects the posture of the vehicle body 1501 based on the signal and controls the hardness of the suspension according to the detection result. The brakes of the individual wheels 1503 can be controlled. In addition, such posture control can be used by a biped robot or a radio control helicopter. As described above, the vibration element 1 is incorporated in realizing the posture control of various moving bodies.

  As described above, the resonator element, the vibrator, the electronic device, and the moving body of the present invention have been described based on the illustrated embodiment. However, the present invention is not limited to this, and the configuration of each part has the same function. Any configuration can be substituted. In addition, any other component may be added to the present invention. Further, the present invention may be a combination of any two or more configurations (features) of the above embodiments.

Specifically, for example, the first beam and the fourth beam have the beam shape of the first embodiment, the second beam and the third beam have the beam shape of the second embodiment, and the first and third beams are the first beam shape. The beam shape of the first embodiment may be used, and the second and fourth beams may be the beam shape of the second embodiment. Thereby, it becomes a vibration element which can exhibit both the effect of 1st Embodiment and the effect of 2nd Embodiment.
Further, in the above-described embodiment, the configuration in which the vibration element has four beams has been described, but the number of beams is not particularly limited, and may be 1 to 3, or 5 or more. There may be. More specifically, for example, the second support portion and the second and fourth beams may be omitted, and the first support portion and the first and third beams may be supported on one side.

  In the embodiment described above, each beam has a configuration in which a total of four extending portions extending in the X-axis direction and extending portions extending in the Y-axis direction are connected alternately. The configuration of the beam is not limited to this. For example, a total of six extending portions extending in the X-axis direction and extending portions extending in the Y-axis direction are connected. There may be a configuration in which a total of eight are connected alternately.

  In the embodiment described above, the vibration unit included in the vibration element includes the base, the first and second detection arms, the first and second connection arms, and the first to fourth drive arms. However, the configuration of the vibration unit is not limited to this. For example, a base, a pair of drive arms extending from the base in the + Y-axis direction and arranged side by side in the X-axis direction, and extending from the base to the −Y-axis direction and arranged side by side in the X-axis direction A configuration having a pair of detection arms may be used. In this case, the beam can be arranged to pass between the detection arm and the drive arm so as to connect the base portion and the support portion. In this configuration, when an angular velocity around the Y axis is applied in a state where the pair of driving arms is driven in the driving mode that is the X anti-phase mode, vibration in the detection mode that drives the pair of detecting arms in the Z anti-phase mode. Is excited. Then, the angular velocity around the Y axis can be detected based on the signal output from the detection arm at that time.

  DESCRIPTION OF SYMBOLS 1 ... Vibration element 2 ... Piezoelectric substrate 20 ... Vibrating part 21 ... Base part 221 ... 1st detection arm 2211 ... Hammer head 222 ... 2nd detection arm 2221 ... Hammer head 231 ... 1st connection arm 232 …… Second connecting arm 241 …… First driving arm 2411 …… Hammer head 242 …… Second driving arm 2421 …… Hammer head 243 …… Third driving arm 2431 …… Hammer head 244 …… Fourth driving arm 2441 …… Hammer head 251 …… First support portion 252 …… Second support portion 261 …… First beam 261A …… Upper beam portion 261B …… Lower beam portion 261C …… Through hole 261D …… Inner beam portion 261E …… Outer beam portion 261F …… Through hole 261G …… Inner beam portion 261H …… Outer beam portion 261I …… Through hole 2611 …… Extension portion 261 …… Extension part 2613 …… Extension part 2614 …… Extension part 262 …… Second beam 263 …… Third beam 264 …… Fourth beam 311 …… Detection signal electrode 312 …… Detection signal terminal 321 …… Detection ground electrode 322 ... Detection ground terminal 331 ... Drive signal electrode 332 ... Drive signal terminal 341 ... Drive ground electrode 342 ... Drive ground terminal 71 ... Drive circuit 711 ... I / V conversion circuit 712 ... AC Amplifier circuit 713 ... Amplitude adjustment circuit 72 ... Detection circuit 721 ... Charge amplifier circuit 722 ... Charge amplifier circuit 723 ... Differential amplification circuit 724 ... AC amplification circuit 725 ... Synchronous detection circuit 726 ... Smoothing circuit 727 ...... Variable amplifier circuit 728 ... Filter circuit 8 ... Package 81 ... Base 811 ... Recess 811a ... First recess 81 b ...... second recess 811c ...... third recess 82 ... lid 831, 832, 833, 834, 835, 836 ... connection terminal 861, 862, 863, 864, 865, 866 ... conductive adhesive 871, 872, 873, 874, 875, 876 ... connection wiring 9 ... IC chip 10 ... vibrator 100 ... physical quantity sensor 1000 ... physical quantity detection device 1100 ... personal computer 1102 ... keyboard 1104 ... main body 1106 ... Display unit 1108 ... Display unit 1200 ... Mobile phone 1202 ... Operation buttons 1204 ... Earpiece 1206 ... Mouthpiece 1208 ... Display unit 1300 ... Digital still camera 1302 ... Case 1304 ... Light receiving unit 1306 …… Shutter button 130 …… Memory 1310 …… Display 1312 …… Video signal output terminal 1314 …… Input / output terminal 1430 …… TV monitor 1440 …… Personal computer 1500 …… Automobile 1501 …… Body 1502 …… Body attitude control device 1503 …… Wheel G: Center of gravity T1, T2: Both ends d, D: Thickness w, W: Width

Claims (11)

A vibrating part;
A support part for supporting the vibration part;
A beam connecting the vibrating portion and the support portion;
The beam has a through-hole penetrating two different places on the surface of the beam.   2. The vibration element according to claim 1, wherein the through-hole passes through two portions of the beam that are opposed to each other in a thickness direction of the vibration portion.   2. The vibration element according to claim 1, wherein the through-hole passes through two locations of the beam that face each other in an in-plane direction of the vibration portion.   The 1st site | part located in one side with respect to the said through-hole of the said beam, and the 2nd site | part located in the other side are provided symmetrically via the said through-hole. Vibration element.   5. The vibration element according to claim 1, wherein the through hole is provided in 50% or more of the total length of the beam.   The vibration element according to claim 1, wherein the through-hole is provided at least at both ends of the beam. The beam has a first extension portion extending in a predetermined direction and a second extension portion extending in a direction different from the predetermined direction,
The vibration element according to claim 1, wherein the through hole is formed in at least a part of the first extension part and at least a part of the second extension part. The vibrating part includes a base part,
A detection arm extending along the first axis from the base;
A connecting arm extending along a second axis intersecting the first axis from the base;
A drive arm extending from the connection arm along the first axis,
The vibrating element according to claim 1, wherein the beam passes between the detection arm and the drive arm and connects the base portion and the support portion. The vibration element according to any one of claims 1 to 8,
And a package containing the vibration element.   An electronic apparatus comprising the vibration element according to claim 1.   A moving body comprising the vibration element according to claim 1.

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