JP2011015102A - Flexural-mode tuning-fork type crystal vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To attenuate vibration to a supporting part.SOLUTION: A flexural-mode tuning-fork type crystal vibrator includes a base, a pair of vibrating arms extending from the base, and a pair of support arms extending from the base along the vibrating arms where the vibrating arms extend from the base inside the support arms provided in the pair, and the support arms have first concave portions in groove shapes to the overall width in the width direction. The support arms may be provided having the first concave portions on both principal surfaces of the vibrating arms at a predetermined interval without facing each other.

Description

  The present invention relates to a tuning fork-type bent quartz crystal resonator used in electronic equipment.

Conventionally, a piezoelectric vibrator or a piezoelectric oscillator is mounted as an electronic component in an electronic device such as a computer, a mobile phone, or a small information device. This piezoelectric vibrator or piezoelectric oscillator is used as a reference signal source or a clock signal source. In addition, the piezoelectric vibrator and the piezoelectric oscillator have a tuning fork-type bent quartz crystal made of quartz inside.
Hereinafter, a tuning fork-type bending quartz crystal resonator using quartz as a piezoelectric material will be described.

FIG. 16 is a perspective view showing an example of a conventional tuning fork-type bent quartz resonator. FIG. 17 is a perspective view showing an example of a piezoelectric piece used in a conventional tuning fork-type bent quartz resonator.
As shown in FIG. 16, the tuning fork type quartz crystal resonator 400 includes a piezoelectric piece 410 (see FIG. 17), excitation electrodes 421a, 421b, 422a and 422b provided on the surface of the piezoelectric piece 410, and a connection The electrodes 423a and 423b, frequency adjusting metal films 424a and 424b, and conductive wiring patterns 425 and 426 are roughly configured (see, for example, Patent Document 1 and Patent Document 2).

As shown in FIG. 17, the piezoelectric piece 410 includes a base portion 411 that is a substantially rectangular flat plate in plan view, a vibrating arm portion 412 that extends in the same direction from one side of the base portion 411, and extends from the other side of the base portion 411. It is comprised by the extended support arm part 413,414 (for example, refer patent document 3).
Hereinafter, since the vibrating arm portion 412 is configured as a pair of two, it will be described as a first vibrating arm portion 412a and a second vibrating arm portion 412b.
Further, since the support arm portions 413 and 414 are configured as a pair of two, the first support arm portion 413 and the second support arm portion 414 will be described.

The 1st support arm part 413 is comprised from the 1st extension part 413a and the 2nd extension part 413b.
The first extending portion 413a extends from the base portion 411 in a direction perpendicular to the extending direction of the first vibrating arm portion 412a and the second vibrating arm portion 412b. The second extending portion 413b extends from a predetermined position of the first extending portion 413a in parallel with the first vibrating arm portion 412a.
The second support arm portion 414 includes a first extension portion 414a and a second extension portion 414b.
The first extending portion 414a is a direction perpendicular to the extending direction of the first vibrating arm portion 412a and the second vibrating arm portion 412b, and the first extending portion of the first supporting arm portion 413. It extends from the base part 411 in the direction opposite to the protruding part 413a. The second extending portion 414b extends from a predetermined position of the first extending portion 414a in parallel with the second vibrating arm portion 412b.

  The piezoelectric piece 410 includes a base portion 411, a first vibrating arm portion 412a, a second vibrating arm portion 412b, a first supporting arm portion 413, and a second supporting arm portion 414 that are integrally formed (for example, Patent Document 1).

As shown in FIG. 16, the excitation electrode 421 a is provided on the front and back main surfaces of the first vibrating arm portion 412 a constituting the piezoelectric piece 410 facing each other. The front and back main surfaces are the surfaces formed with the largest surface area of the base part 411, and are two surfaces in which one surface and the other surface are parallel to each other. The surface facing the same direction is also included. In FIG. 16 and FIG. 17, a surface appearing in the drawings is a “front surface”, and a hidden surface is a “back surface”.
The excitation electrode 421b is provided on both opposing side surfaces of the first vibrating arm portion 412a. Further, the excitation electrode 422a is provided on the front and back main surfaces of the second vibrating arm portion 412b facing each other. Further, the excitation electrode 422b is provided on both opposite side surfaces of the second vibrating arm portion 412b.

The connection electrode 423 a is provided on the entire front and back main surfaces of the first support arm 413.
The connection electrode 423a is electrically connected to the excitation electrode 422a of the second vibrating arm 413 through a conductive wiring pattern provided on the back main surface of the base 411.
The connection electrode 423a is also electrically connected to the excitation electrode 421b and the frequency adjustment metal film 424a provided on both side surfaces of the first vibrating arm portion 412a.
The excitation electrode 422a provided on the front and back main surfaces of the second vibrating arm portion 412b is electrically connected to the exciting electrode 421b of the first vibrating arm portion 412a by a conductive wiring pattern 426.

The connection electrode 423 b is provided on the entire front and back main surfaces of the second support arm 414.
The connection electrode 423b is electrically connected to the excitation electrode 421a through a conductive wiring pattern 425 provided on the main surface of the base 411.
The connection electrode 423b is also electrically connected to the excitation electrode 422b and the frequency adjusting metal film 424b provided on both side surfaces of the second vibrating arm portion 412b.
The excitation electrode 421a provided on the front and back main surfaces of the first vibrating arm portion 412a is electrically connected to the exciting electrode 422b of the second vibrating arm portion 412b by a conductive wiring pattern.

The frequency adjusting metal film 424a is provided on the front surface and the tip of the side surface of the first vibrating arm portion 412a, and is electrically connected to the excitation electrodes 421b provided on both side surfaces of the first vibrating arm portion 412a. Connected. In addition, the frequency adjusting metal film 424b is provided on the front surface and the tip of the side surface of the second vibrating arm portion 412b, and is electrically connected to the excitation electrode 422b provided on both side surfaces of the second vibrating arm portion 412b. Connected.
Note that the piezoelectric vibration element 400 can adjust the vibration frequency value to a desired value by increasing or decreasing the amount of the metal constituting the frequency adjusting metal films 424a and 424b.

  In addition, for the tuning fork type bending crystal resonator having the support arm portion, a structure in which a notch is provided in the thickness direction of the support arm portion has been proposed, and the vibration leaking from the vibration arm portion is attenuated by this notch, The vibration is prevented from propagating (for example, see Patent Document 4).

Further, as another structure of the tuning fork-type bent quartz resonator, a structure in which a groove-like recess is formed on the main surface of the base has been proposed. This tuning fork-type bent quartz crystal resonator has a groove-like recess formed so as to attenuate the vibration leaking from the vibrating arm and prevent the propagation of the vibration (see, for example, Patent Document 5).
Similarly, the tuning-fork type bending crystal resonator disclosed in Patent Document 5 also attenuates the vibration leaking from the vibrating arm portion by the groove-like concave portion provided on the main surface of the base portion to prevent the propagation of the vibration.

Note that these tuning fork-type bent quartz crystal resonators are mounted on, for example, an element connection electrode pad formed on the bottom surface of the recess of an element mounting member having a recess having an opening on one main surface. The opening is hermetically sealed by a lid to form a piezoelectric vibrator (see, for example, Patent Document 6).
In addition, these tuning-fork type bent quartz resonators are mounted on, for example, an element connection electrode pad formed on the bottom surface of the recess of an element mounting member having a recess having an opening on one main surface, The opening is hermetically sealed with a lid, and at least an integrated circuit element including an oscillation circuit is electrically connected to the piezoelectric vibration element to form a piezoelectric oscillator (see, for example, Patent Document 6).

JP 2004-357178 A JP 2004-297198 A JP-A-2005-94724 JP 2006-148857 A Japanese Utility Model Publication No. 51-138076 JP 2008-252800 A

However, as the tuning fork type bent quartz crystal unit becomes smaller, the outer shape of the element is relied on chemical etching. However, in the chemical etching, the thickness direction of the tuning fork type bent crystal unit provided on the support arm portion is relied on. Since a residue is generated in the notch, it is difficult to form into an accurate shape. Due to such a residue, the vibration is not sufficiently attenuated by the notch and is propagated to the portion where the vibration is supported, and the value of the frequency deviation at a predetermined temperature (hereinafter referred to as “temperature characteristic”) is deteriorated. In addition, the value of crystal impedance (hereinafter sometimes referred to as “CI value”) may be deteriorated.
In addition, the tuning fork-type bending quartz crystal whose supporting arm part is not a part of the constituent element has a groove-like recess in the width direction of the base part, that is, in the direction perpendicular to the direction in which the vibrating arm part extends from the base part. Even if formed, the vibration leaking from the vibrating arm portion cannot be sufficiently attenuated, and the temperature characteristics and the CI value may be deteriorated.

  Accordingly, an object of the present invention is to provide a tuning fork-type bent quartz crystal resonator that solves the above-described problems, attenuates vibration from the vibrating arm portion, and reduces propagation of vibration.

  In order to solve the above-described problems, the present invention provides a base, a pair of two vibrating arms extending from the base, and a pair of supporting arms extending from the base along the vibrating arms. The vibrating arm portion is configured to extend from the base portion on the inner side of the support arm portion provided in pairs, and the support arm portion includes a groove-shaped first recess in the width direction. This is a tuning fork-type bent quartz crystal.

  In the present invention, the support arm portion may be provided with a predetermined interval without facing each other while having the first concave portion on the front and back main surfaces of the vibrating arm portion.

  In the present invention, the support arm portion may extend from a position away from the boundary between the base portion and the vibrating arm portion in a direction perpendicular to the extending direction of the vibrating arm portion. It may be configured to extend in parallel with the vibrating arm portion at a position.

  Further, in the present invention, the base is between a boundary between the base and the vibrating arm and a boundary between the base and the supporting arm, with respect to a direction in which the vibrating arm extends. You may comprise having a groove-shaped 2nd recessed part in the direction which becomes a right angle.

  In the present invention, the base portion may be provided at a predetermined interval without facing each other while having the second concave portion on the front and back main surfaces of the base portion.

  In the present invention, the support arm portion may be configured to have a groove-like third concave portion in the width direction on the boundary side with the base portion.

  In the present invention, the support arm portion may be provided at a predetermined interval without facing each other while having the third concave portion on the front and back main surfaces of the vibrating arm portion.

  In the present invention, each of the pair of vibrating arm portions may have a groove-shaped fourth recess that is shorter than the vibrating arm portion.

  Further, the present invention may be configured such that each of the pair of vibrating arm portions has a groove-shaped fourth concave portion in which two or more shorter than the vibrating arm portion are arranged.

  According to such a tuning fork type bent quartz crystal resonator, the support arm portion extending from the base portion has the groove-shaped first concave portion in the width direction thereof, so that the first concave portion is formed by chemical etching. Even if formed, the change in shape due to the residue can be reduced. In addition, since the support arm portion extending from the base portion has a groove-shaped first recess in the width direction, vibration leaking from the vibrating arm portion reaches the first recess of the support arm portion. Since the vibration is further attenuated by the first recess after being attenuated by the base or the supporting arm partway, it is possible to reduce the propagation of vibration to the supporting part and prevent deterioration of temperature characteristics and CI value. it can.

  Further, according to the present invention, since the support arm portion has the first recess on the front and back main surfaces of the vibrating arm portion and is provided at a predetermined interval without facing each other, the front main surface side The vibration propagating on the back main surface side can be attenuated while the vibration propagating through is attenuated.

  Further, in the present invention, when the width of the base portion is a direction perpendicular to the extending direction of the vibrating arm portion, and the length of the base portion is a direction perpendicular to the direction defined as the width, the support arm portion Even if the width is smaller than the length of the base portion, vibration leaking from the vibrating arm portion can be attenuated by the first concave portion of the support arm portion.

  In the present invention, since the second concave portion is provided in the width direction of the base portion, the vibration is attenuated by the first concave portion of the support arm portion and the vibration is attenuated by the second concave portion of the base portion. Damping of vibration leaking from the arm portion can be further improved.

  In the present invention, the second recesses on the front and back main surfaces of the base are provided at predetermined intervals without facing each other. Vibrations propagating on the surface side can be attenuated.

  Further, in the present invention, since the support arm part is on the boundary side with the base part and has a groove-shaped third recess part in the width direction, in addition to the vibration attenuation by the first recess part of the support arm part. Since the vibration can be attenuated by the third recess, it is possible to further improve the attenuation of vibration leaking from the vibrating arm portion.

  Further, according to the present invention, the third recesses provided on the front and back main surfaces of the support arm portion are provided at predetermined intervals without facing each other, so that vibration propagating on the front main surface side is attenuated. The vibration propagating on the back main surface side can be attenuated.

  Further, the present invention is configured such that the support arm portion extends in a direction opposite to the vibrating arm portion extending from the base portion, and vibration leaking from the vibrating arm portion is attenuated by the first recess portion of the support arm portion. Can be made.

  Further, in the present invention, each of the pair of vibrating arms has a structure having a groove-shaped fourth recess shorter than the vibrating arm portion, and the supporting arm portion has vibration leaking from the vibrating arm portion. It can be attenuated at the first recess.

  Further, according to the present invention, each of the pair of vibrating arms has a structure having a groove-like fourth concave portion in which two or more shorter than the vibrating arm portions are arranged, and vibration leaks from the vibrating arm portions. Can be attenuated by the first concave portion of the support arm portion.

It is a perspective view which shows an example of the tuning fork type bending quartz crystal vibrator concerning a first embodiment of the present invention. It is a perspective view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a first embodiment of the present invention. It is a perspective view which shows an example of the tuning fork type | mold bending crystal oscillator based on the modification of 1st embodiment of this invention. It is a conceptual diagram which shows an example of the state of a 1st recessed part. It is a perspective view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a second embodiment of the present invention. It is a perspective view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning the modification of the second embodiment of the present invention. (A) is a perspective view which shows an example of the piezoelectric piece used for the tuning fork type | mold bending crystal resonator which concerns on 3rd embodiment of this invention, (b) is used for the tuning fork type | mold bending crystal resonator of (a). It is a conceptual diagram of a piezoelectric piece. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning the modification of 3rd embodiment of this invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a 4th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning the modification of the 4th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a 5th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning the modification of the 5th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a 6th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning a 7th embodiment of the present invention. It is a top view which shows an example of the piezoelectric piece used for the tuning fork type bending quartz crystal vibrator concerning the further modification of this invention. It is a perspective view which shows an example of the conventional tuning fork type bending crystal oscillator. It is a perspective view which shows an example of the piezoelectric piece used for the conventional tuning fork type bending crystal oscillator.

  The best mode for carrying out the present invention (hereinafter referred to as “embodiment”) will be described in detail with reference to the drawings as appropriate. Note that each component is exaggerated for easy understanding of the state.

(First embodiment)
As shown in FIG. 1, the tuning-fork type bending crystal resonator 100 according to the first embodiment of the present invention includes a piezoelectric piece 110a (see FIG. 2) and an excitation electrode 121a provided on the surface of the piezoelectric piece 110a. 121b, 122a and 122b, connection electrodes 123a and 123b, frequency adjusting metal films 124a and 124b, and conductive wiring patterns 125 and 126.

As shown in FIGS. 1 and 2, the piezoelectric piece 110 a is made of, for example, quartz and has a base portion 111 that is a substantially rectangular flat plate shape in plan view, and a pair of two extending in one direction from one side of the base portion 111 The vibrating arm portion 112 and support arm portions 113 and 114 extending from the base portion 111 are configured.
In addition, since the vibration arm part 112 is a pair of two, it demonstrates as the 1st vibration arm part 112a and the 2nd vibration arm part 112b. Further, since the support arm portions 113 and 114 are a pair of two, the first support arm portion 113 and the second support arm portion 114 will be described.

The 1st support arm part 113 is comprised from the 1st extension part 113a and the 2nd extension part 113b.
The first extending portion 113a extends from the side portion of the base portion 111 on the first vibrating arm portion 112a side in a direction perpendicular to the extending direction of the first vibrating arm portion 112a with a predetermined length. Has been.
The second extending portion 113b extends from the end of the first extending portion 113a with a predetermined length in the same direction as the extending direction of the first vibrating arm portion 112a.
A first recess 31 is provided in the second extension 113b.

The first recess 31 included in the second extension 113b is formed in a groove shape, and has a length shorter than the entire width of the second extension 113b, and the vibrating arm of the second extension 113b. It is provided close to the part 112 side.
The first recess 31 is provided at a position away from a position where a conductive adhesive used for mounting is attached. For example, when the tip portion of the second extension portion 113b is a portion to which a conductive adhesive can be applied, it is provided at a position away from the tip portion of the second extension portion 113b toward the first extension portion 113a. Will be.

  In the second extending portions 113b and 114b, the direction perpendicular to the direction extending from the first extending portions 113a and 114a is defined as the width, and the extending direction is defined as the length direction.

The cross-sectional shape of the first recess 31 may be formed in, for example, a U-shape, a V-shape, or a cross-sectional shape in which wall surfaces are formed so that the inclination angles are different.
The first recess 31 is formed with a depth exceeding the center of the thickness of the second extension 113b.
Therefore, the first recess 31 can reduce the propagation of the vibration to the supporting portion by attenuating the vibration leaked from the vibrating arm portion 112 and can reduce the reflected wave returning to the vibrating arm portion 112. .

The second support arm portion 114 includes a first extension portion 114a and a second extension portion 114b.
The first extending portion 114a extends from the side portion of the base 111 on the second vibrating arm portion 112b side in a direction perpendicular to the extending direction of the second vibrating arm portion 112b with a predetermined length. Has been.
The second extending portion 114b extends from the end of the first extending portion 114a with a predetermined length in the same direction as the extending direction of the second vibrating arm portion 112b.
The second recess 114b is also provided with the first recess 31.

The first recess 31 included in the second extension portion 114b is formed in a groove shape, and has a length shorter than the entire width of the second extension portion 114b, and the vibrating arm of the second extension portion 114b. It is provided close to the part 112 side.
The cross-sectional shape of the first recess 31 may be formed in, for example, a U-shape, a V-shape, or a cross-sectional shape with wall surfaces formed so as to have different inclination angles.
The first recess 31 is formed with a depth exceeding the thickness center of the second extension 114b.

  Therefore, the first concave portion 31 can reduce the vibration that leaks from the vibrating arm portion 112 and reduce the propagation of the vibration to the supporting portion, and can reduce the reflected wave returning to the vibrating arm portion 112. . In addition, the first recess 31 can reduce the vibration that has leaked from the vibrating arm portion 112 and reduce the propagation of the vibration to the supporting portion, and can reduce the reflected wave that returns to the vibrating arm portion 112. .

  Similarly, the first recess 31 is provided at a position away from a position where a conductive adhesive used for mounting is attached. For example, when the tip portion of the second extending portion 113b, 114b is a portion to which the conductive adhesive can be applied, that is, the supporting portion, the first extending portion from the tip portion of the second extending portion 113b, 114b. It will be provided at a position away from the projecting portions 113a and 114a.

The first concave portion 31 provided in the first support arm portion 113 and the first concave portion 31 provided in the second support arm portion 114 are arranged on the same straight line so as to be positioned on the same straight line. Provided in the extending portions 113b and 114b.
Moreover, the external shape of such a 1st recessed part 31 can be formed using a well-known photolithography technique and an etching technique.

As shown in FIG. 1, the excitation electrode 121a is provided on the front and back main surfaces of the first vibrating arm portion 112a. In addition, the excitation electrode 121b is provided on both opposing side surfaces of the first vibrating arm portion 112a.
The frequency adjusting metal film 124a is provided on the front surface and the tip of the side surface of the first vibrating arm portion 112a, and is electrically connected to the excitation electrodes 121b provided on both side surfaces of the first vibrating arm portion 112a. Connected.
Connecting electrode 123a
Are provided on the front and back main surfaces of the first support arm 113.

The excitation electrode 122a is provided on the front and back main surfaces of the second vibrating arm portion 112b. The excitation electrode 122b is provided on both opposing side surfaces of the second vibrating arm portion 112b.
The frequency adjusting metal film 124b is provided on the front surface and the tip of the side surface of the second vibrating arm portion 112b, and is electrically connected to the excitation electrodes 122b provided on both side surfaces of the second vibrating arm portion 112b. Connected.
The connection electrode 123b is provided on the front and back main surfaces of the second support arm 114.

  Note that the tuning fork type quartz crystal resonator 100 can adjust the vibration frequency value to a desired value by increasing or decreasing the amount of metal constituting the frequency adjusting metal films 124a and 124b.

As shown in FIG. 1, the excitation electrodes 121a and 122b, the frequency adjusting metal film 124b, and the connection electrode 123b are electrically connected by, for example, a conductive wiring pattern 125 provided on the surface of the piezoelectric piece 110a. Yes. The connection electrode 123b is provided on the entire surface of the second support arm portion 114, and is electrically connected to the excitation electrode 122b provided on the side surface of the second vibration arm portion 112b.
The excitation electrode 121 a provided on the front main surface of the first vibrating arm portion 112 a is electrically connected to the connection electrode 123 b through the conductive wiring pattern 125.
The excitation electrode 121a provided on the back main surface of the first vibrating arm portion 112a is provided on a side surface facing the inside of the second vibrating arm portion 112b via a conductive wiring pattern (not shown). It is electrically connected to the excitation electrode 122b.

As shown in FIG. 1, the excitation electrodes 121b and 122a, the frequency adjusting metal film 124a, and the connection electrode 123a are electrically connected by, for example, a conductive wiring pattern 126 provided on the surface of the piezoelectric piece 110a. is doing. The connection electrode 123a is provided on the entire surface of the first support arm portion 113, and is electrically connected to the excitation electrode 121b provided on the side surface of the first vibration arm portion 112a.
In addition, the excitation electrode 122a provided on the back main surface of the second vibrating arm portion 112b is electrically connected to the connection electrode 123a through a conductive wiring pattern (not shown).
The excitation electrode 122a provided on the front main surface of the second vibrating arm portion 112a is provided on the side surface facing the inside of the first vibrating arm portion 112a via the conductive wiring pattern 126. And is electrically connected.

  Each excitation electrode, connection electrode, frequency adjusting metal film, and conductive wiring pattern are composed of, for example, a Cr layer as a base metal and an Au layer provided on the base metal. Yes.

  When vibrating the tuning fork-type bent quartz crystal resonator 100, an alternating voltage is applied to the connection electrodes 123a and 123b. When an electrical state after application is instantaneously captured, the excitation electrode 121b of the first vibrating arm portion 112b has a + (plus) potential, the excitation electrode 121a has a-(minus) potential, and changes from + to-. An electric field is generated. On the other hand, the excitation electrodes 122a and 122b of the second vibrating arm portion 112b at this time have a polarity opposite to the polarity generated in the exciting electrodes 121a and 121b of the first vibrating arm portion 112a. These applied electric fields cause an expansion / contraction phenomenon in the first vibrating arm portion 112a and the second vibrating arm portion 112b, and a bending vibration having a resonance frequency set in each vibrating arm portion 112 is obtained.

  The tuning fork-type bent quartz crystal resonator 100 can form the excitation electrode, the connection electrode, the conductive wiring pattern, and the frequency adjusting metal film on the surface of the piezoelectric piece 110a by the photolithography technique and the vapor deposition technique. Further, the tuning fork type bent quartz crystal resonator 100 is mounted on, for example, an element connection electrode pad formed on the bottom surface in the concave portion of a container body provided with a concave portion having an opening portion on one main surface. The opening is hermetically sealed with a lid to form a crystal resonator.

According to the tuning fork-type quartz crystal resonator 100 described above, the first recess 31 is formed in the first support arm 113 and the second support arm 114 that constitute the piezoelectric piece 110a, and the second extension 114b. The vibration that leaks from the first vibrating arm portion 112a and the second vibrating arm portion 112b has a length shorter than the entire width and is provided close to the vibrating arm portion 112 side of the second extending portion 114b. After the first recess 31 of the support arm 113 and the first recess 31 of the second support arm 114 reach the first recess 31, the first recess 31, 31 can further reduce the propagation of vibration. Thus, the first recesses 31 and 31 reduce reflection of vibration leaked from the first vibrating arm portion 112a and the second vibrating arm portion 112b, and the first vibrating arm portion 112a and the second vibrating arm portion. It is possible to prevent the vibration of the portion 112b from being hindered.
Further, the first concave portion 31 of the first support arm portion 113 and the first concave portion 31 of the second support arm portion 114 can be easily formed without considering the etching residue.

(Modification of the first embodiment)
As shown in FIG. 3, the tuning-fork type bending crystal resonator according to the modification of the first embodiment of the present invention includes a piezoelectric piece 110b used for the tuning-fork type bending crystal resonator. The first concave portion 31 provided in the second support arm portion 114 is formed with the front and back main surfaces of the second extension portion 113b, which is a component of the first support arm portion 113, and the second support arm portion 114. The second embodiment differs from the first embodiment in that it is provided on the front and back main surfaces of the second extending portion 114b, which is a component.
Hereinafter, the description which overlaps about the component same as 1st embodiment is abbreviate | omitted, and attaches | subjects the same code | symbol.

First, as shown in FIG. 3, the first concave portion 31 provided in the first support arm portion 113 is formed on the front and back main surfaces of the second extension portion 113 b and the first concave portion on the front main surface side. The recessed portion 31 and the first recessed portion 31 on the back main surface side are not opposed to each other and are provided with a predetermined interval.
For example, the 1st recessed part 31 provided in the front main surface is provided in the position near the 1st extension part 113a side rather than the 1st recessed part 31 provided in the back main surface.

Next, the 1st recessed part 31 provided in the 2nd support arm part 114 is formed in the front-and-back main surface of the 2nd extension part 114b, and the 1st recessed part 31 and back-side surface of the front main surface side are formed. The first concave portion 31 on the surface side is not opposed to the first concave portion 31 and is provided at a predetermined interval.
For example, the 1st recessed part 31 provided in the front main surface is provided in the position near the 1st extension part 114a side rather than the 1st recessed part 31 provided in the back main surface.

The first recess 31 will be specifically described. The depth of the first recess 31 is greater than 50% and less than 90% with respect to the thickness of the base 111.
For example, when the depth of the first concave portion 31 is 50% or less, the vibration propagating through the support arm portions 113 and 114 passes through the first concave portion 31, and the vibration leaks and the CI is leaked. It becomes difficult to improve the value. Moreover, when the depth of the 1st recessed part 31 is 90% or more, the intensity | strength of the support arm parts 113 and 114 cannot be ensured and there exists a possibility of damaging in the middle of manufacture.
Therefore, as shown in FIG. 4, the first concave portion 31 attenuates the vibration W propagating on the front main surface by the first concave portion 31 provided on the front main surface side, and propagates the vibration W propagating on the back main surface. Is attenuated by the first recess 31 provided on the back main surface side. In addition, since each of the first recesses 31 is formed at a depth exceeding the center CL of the thickness of the support arm portions 113 and 114, vibration propagating through the support arm portions 113 and 114 is also caused by the first recess 31. Can be attenuated. Accordingly, the first recess 31 can attenuate the vibration leaking from the vibrating arm portion 112 and further attenuate the vibration propagating to the supporting portions of the support arm portions 113 and 114.

(Second embodiment)
As shown in FIG. 5, the tuning fork type quartz crystal resonator according to the second embodiment of the present invention is a piezoelectric piece 110 c used in the tuning fork type quartz crystal resonator. The first extending portion 114a of the extending portion 113a and the second support arm portion 114 extends from a position away from the boundary between the first vibrating arm portion 112a and the second vibrating arm portion 112b and the base portion 111. This is different from the first embodiment.
That is, even if it comprises 2nd embodiment in this way, there exists an effect similar to 1st embodiment. Moreover, even if this second embodiment is combined with the modification of the first embodiment, the same effects as the modification of the first embodiment can be obtained.

(Modification of the second embodiment)
As shown in FIG. 6, the tuning fork-type bent quartz crystal resonator according to the modification of the second embodiment of the present invention includes the piezoelectric piece 110 d having the second extending portion 113 b and the first extending portion 113 b of the first supporting arm portion 113. The second embodiment differs from the second embodiment in that the first recess 31 provided in the second extension 114b of the second support arm 114 is provided on the front and back main surfaces.
The first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 are respectively connected to the second extension 113b,
114b is provided at a predetermined interval so as not to face the front and back main surfaces of 114b.
The first concave portion 31 provided on the front main surface is provided closer to the first extending portions 113a and 114a than the first concave portion 31 provided on the back main surface.
Thus, since the modification of 2nd embodiment was comprised, the 1st recessed part 31 of the front and back main surfaces of the 1st support arm part 113 and the 2nd support arm part 114 is provided at predetermined intervals. Therefore, the vibration can be further attenuated with respect to the configuration of the second embodiment.

(Third embodiment)
As shown in FIGS. 7A and 7B, the tuning fork-type bent quartz crystal resonator according to the third embodiment of the present invention has a piezoelectric piece 110e having a second recess 32 in the width direction of the base 111. This is different from the second embodiment. Here, the width of the base 111 is a direction perpendicular to the extending direction of the first vibrating arm 112 a and the second vibrating arm 112 b extending from the base 111.
At this time, the second concave portion 32 has a length shorter than the entire width of the base portion 111, except for a portion where the excitation electrodes 121 a, 121 b, 122 a and 122 b and the connection electrodes 123 a and 123 b are electrically connected. 111 is provided in a groove shape over the entire width.
The second recess 32 is provided on the base 111 so as to be positioned on the same straight line LN as the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114. ing.
As described above, since the third embodiment is configured, in addition to the vibration attenuation by the first recess 31 of the first support arm 113 and the second support arm 114, the second of the base 111 is provided. Since the vibration can be attenuated by the concave portion 32, it is possible to improve the reduction of the propagation of vibration leaking from the first vibrating arm portion 112a and the second vibrating arm portion 112b.

(Modification of the third embodiment)
As shown in FIG. 8, in the tuning fork-type bent quartz crystal resonator according to the modification of the third embodiment of the present invention, the piezoelectric piece 110 f has the second recess 32 extending in the width direction on the front and back main surfaces of the base 111. It differs from the third embodiment in having it.
The first concave portion 31 of the first support arm portion 113 and the first concave portion 31 of the second support arm portion 114 are set so as not to face the front and back main surfaces of the respective second extending portions 113b and 114b. Are provided at intervals.
The first concave portion 32 provided on the front main surface side of the base 111 is closer to the first vibrating arm portion 112a and the second vibrating arm portion 112b than the second concave portion 32 provided on the back main surface side. Provided.
The second recess 32 will be specifically described. The depth of the second recess 32 is greater than 50% and less than 90% with respect to the thickness of the base 111.
For example, when the depth of the second concave portion 32 is 50% or less, the vibration propagating through the base 111 passes through the second concave portion 32 and the vibration leaks to improve the CI value. It becomes difficult. Moreover, when the depth of the 2nd recessed part 32 is 90% or more, the intensity | strength of the base 111 cannot be ensured and there exists a possibility of damaging in the middle of manufacture.
Therefore, like the concept shown in FIG. 4, the second recess 32 attenuates the vibration W propagating on the front main surface by the second recess 32 provided on the front main surface side and propagates the back main surface. The vibration W is attenuated by the second recess 32 provided on the back main surface side. In addition, since each second recess 32 is formed with a depth exceeding the center of the thickness of the base 111, vibration propagating through the base 111 can also be attenuated by the second recess 32. Therefore, the vibration that has leaked from the vibrating arm portion 112 can be further attenuated by the second recess 32.
Thus, since the modification of 3rd embodiment was comprised, the 2nd recessed part 32 of the front and back main surface of the base 111 is provided at predetermined intervals, and it becomes the structure of 3rd embodiment. On the other hand, vibration can be further attenuated.

(Fourth embodiment)
As shown in FIG. 9, the piezoelectric vibrating element according to the fourth embodiment of the present invention has a piezoelectric piece 110 g in addition to the first recess 31 in the first support arm 113 and the second support arm 114. Further, the third embodiment differs from the first embodiment in that a third recess 33 is provided.
First, the third recess 33 provided in the first support arm portion 113 has a length shorter than the entire width of the first extension portion 113a, and is brought closer to the vibrating arm portion 112 side to the first extension portion 113a. Are provided in a groove shape.
The third recess 33 provided in the second support arm portion 114 is shorter than the entire width of the first extension portion 114a, and is brought closer to the vibrating arm portion 112 side to the first extension portion 114a. Are provided in a groove shape.
As described above, since the fourth embodiment is configured, the first recess 31 included in the first support arm 123 and the first recess 31 included in the second support arm 114 attenuate the vibration. Since the vibration can be attenuated by the three concave portions 33, it is possible to further improve the reduction of the propagation of vibration leaking from the first vibrating arm portion 112a and the second vibrating arm portion 112b.

(Modification of the fourth embodiment)
As shown in FIG. 10, the tuning fork-type bent quartz crystal resonator according to the modification of the fourth embodiment of the present invention includes a piezoelectric piece 110 h that includes the first extension portion 113 a and the first extension portion 113 a of the first support arm portion 113. The second embodiment differs from the fourth embodiment in that a third recess 33 is provided on the front and back main surfaces of the first extension portion 114a of the second support arm portion 114 in the width direction.
First, the third recess 33 provided on the front main surface side of the first extension 113a of the first support arm 113 is closer to the base 111 than the third recess 33 provided on the back main surface side. Provided.
Moreover, the 3rd recessed part 33 provided in the front main surface side of the 1st extension part 114a of the 2nd support arm part 114 is the side closer to the base 111 than the 3rd recessed part 33 provided in the back main surface side. Provided.
The third recess 33 will be specifically described. The depth of the third recess 33 is greater than 50% and 90% or less with respect to the thickness of the base 111.
For example, when the depth of the third concave portion 33 is 50% or less, the vibration propagating through the support arm portions 113 and 114 passes through the third concave portion 33, and the vibration leaks and becomes CI. It becomes difficult to improve the value. Further, when the depth of the third recess 33 is 90% or more, the strength of the support arm portions 113 and 114 cannot be ensured, and there is a possibility that the third recess portion 33 is damaged during the manufacturing.
Accordingly, in the same manner as the concept shown in FIG. 4, the third recess 33 attenuates the vibration W propagating on the front main surface by the third recess 33 provided on the front main surface side, and propagates the back main surface. The vibration W is damped by the third concave portion 33 provided on the back main surface side. Further, since the third recesses 33 are formed with a depth exceeding the center of the thickness of the support arm portions 113, 114, vibration propagating through the support arm portions 113, 114 is also caused by the third recesses 33. Can be attenuated. Therefore, the third recess 33 can attenuate the vibration leaking from the vibrating arm portion 112 and further attenuate the vibration propagating to the supporting portions of the support arm portions 113 and 114.
Thus, since the modification of 4th embodiment was comprised, the 3rd recessed part 33 of the front-back main surface of the 1st support arm part 113 and the 2nd support arm part 114 is provided at predetermined intervals. Therefore, the vibration can be further attenuated with respect to the configuration of the fourth embodiment.

(Fifth embodiment)
As shown in FIG. 11, the tuning-fork type bent quartz crystal resonator according to the fifth embodiment of the present invention is the fourth embodiment in that the second concave portion 32 is provided in the base portion 111 of the piezoelectric piece 110i. And different. That is, the fifth embodiment is configured by combining the third embodiment and the fourth embodiment.
In the fifth embodiment, the piezoelectric piece 110i includes a first support arm portion 113 and a second support arm portion 114 each having a first recess 31 and a third recess 33, and the base 111 is The structure has a second recess 32.
Note that the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. May be provided at predetermined intervals.
Further, the third recess 33 of the first support arm 113 and the third recess 33 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. May be provided at predetermined intervals.
Since the fifth embodiment is configured as described above, the second recess 32 is provided in the base 111, whereby vibration can be further attenuated with respect to the configuration of the fourth embodiment.

(Modification of the fifth embodiment)
As shown in FIG. 12, in the tuning fork type bent quartz crystal resonator according to the modification of the fifth embodiment of the present invention, the piezoelectric piece 110j has the second recess 32 on the front and back main surfaces of the base 111. This is different from the fifth embodiment.
The first concave portion 32 provided on the front main surface side of the base portion 111 is, like the modified example of the fourth embodiment, the first vibrating arm portion 112a than the second concave portion 32 provided on the back main surface side. And provided on the side close to the second vibrating arm portion 112b.
Note that the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. May be provided at predetermined intervals.
Thus, since the modification of 5th Embodiment was comprised, the 2nd recessed part 32 of the front and back main surface of the base 111 is provided at predetermined intervals, and it becomes the structure of 5th Embodiment. On the other hand, vibration can be further attenuated.

(Sixth embodiment)
The tuning-fork type bending quartz crystal resonator according to the sixth embodiment of the present invention is a vibrating arm portion 112 of the piezoelectric pieces 110a to 110j used in the first to fifth embodiments and the modifications. One vibrating arm portion 112 a and second vibrating arm portion 112 b are configured to have a fourth recess 34.
As an example, the piezoelectric piece 110k shown in FIG. 13 will be described.
The piezoelectric piece 110k includes a base 111, a first vibrating arm 112a and a second vibrating arm 112b extending from the base 111, and the first vibrating arm 112a and the second vibrating arm 112b. A first support arm portion 113 and a second support arm portion 114 extending from the base portion 111 in the same direction are provided.

A groove-shaped fourth recess 34 is provided in the first vibrating arm portion 112a and the second vibrating arm portion 112b.
These fourth recesses 34 are the same as the extending direction extending from the bases of the first vibrating arm portion 112a and the second vibrating arm portion 112b, and the first vibrating arm has a predetermined depth. It is formed in the part 112a and the 2nd vibration arm part 112b.
The fourth recess 34 is provided in the first vibrating arm portion 112a and the second vibrating arm portion 112b so as to be shorter than the first vibrating arm portion 112a and the second vibrating arm portion 112b. It is done.
Such a fourth recess 34 does not play a role of reducing the propagation of vibration, and plays a role of reducing the CI value of the first vibrating arm portion 112a and the second vibrating arm portion 112b.

Here, the base 111 has a length shorter than the entire width of the base 111, and the entire width of the base 111 is excluded except for a portion where the excitation electrodes 121a, 121b, 122a and 122b and the connection electrodes 123a and 123b are electrically connected. A groove-shaped second recess 32 is provided over the entire area.
First, the first support arm portion 113 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 113b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 113b. The third recess 33 has a length shorter than the entire width of the first extension 113a and is provided in a groove shape in the first extension 113a close to the vibrating arm 112 side. .
Further, the second support arm portion 114 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 114b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 114b. The third recess 33 has a length shorter than the entire width of the first extension portion 114a and is provided in a groove shape in the first extension portion 114a so as to approach the vibrating arm portion 112 side. .

Note that the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. Are provided at predetermined intervals.
Further, the third recess 33 of the first support arm 113 and the third recess 33 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113a and 114a. Are provided at predetermined intervals.
Thus, even if it comprises 6th embodiment, propagation of the vibration which leaks from the vibrating arm part 112 can be attenuated.

(Seventh embodiment)
The tuning-fork type bent quartz crystal resonator according to the seventh embodiment of the present invention is the vibrating arm portion 112 of the piezoelectric pieces 110a to 110j used in the first to fifth embodiments and the modifications. Each of the one vibrating arm portion 112a and the second vibrating arm portion 112b includes two pairs of fourth concave portions 34.
As an example, a piezoelectric piece 110l shown in FIG. 14 will be described.
The piezoelectric piece 110l includes a base 111, a first vibrating arm 112a and a second vibrating arm 112b extending from the base 111, the first vibrating arm 112a and the second vibrating arm 112b. A first support arm portion 113 and a second support arm portion 114 extending from the base portion in the same direction are provided.

For example, two groove-shaped fourth concave portions 34 are provided in the first vibrating arm portion 112a and the second vibrating arm portion 112b.
These fourth recesses 34 are the same as the extending direction extending from the bases of the first vibrating arm portion 112a and the second vibrating arm portion 112b, and the first vibrating arm has a predetermined depth. It is formed in the part 112a and the 2nd vibration arm part 112b.
The fourth recess 34 is provided in the first vibrating arm portion 112a and the second vibrating arm portion 112b so as to be shorter than the first vibrating arm portion 112a and the second vibrating arm portion 112b. It is done.
Such a fourth recess 34 does not play a role of reducing the propagation of vibration, and plays a role of reducing the CI value of the first vibrating arm portion 112a and the second vibrating arm portion 112b.

Here, the base 111 has a length shorter than the entire width of the base 111, and the entire width of the base 111 is excluded except for a portion where the excitation electrodes 121a, 121b, 122a and 122b and the connection electrodes 123a and 123b are electrically connected. A groove-shaped second recess 32 is provided over the entire area.
First, the first support arm portion 113 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 113b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 113b. The third recess 33 has a length shorter than the entire width of the first extension 113a and is provided in a groove shape in the first extension 113a close to the vibrating arm 112 side. .
Further, the second support arm portion 114 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 114b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 114b. The third recess 33 has a length shorter than the entire width of the first extension portion 114a and is provided in a groove shape in the first extension portion 114a so as to approach the vibrating arm portion 112 side. .

Note that the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. Are provided at predetermined intervals.
Further, the third recess 33 of the first support arm 113 and the third recess 33 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113a and 114a. Are provided at predetermined intervals.
Thus, even if it comprises 7th embodiment, propagation of the vibration which leaks from the vibration arm part 112 can be attenuated.

In addition, although embodiment of this invention was described, this invention can be changed suitably.
For example, it is needless to say that the present invention includes a tuning fork-type bent quartz crystal having a structure obtained by variously combining the second to ninth embodiments based on the first embodiment.
Moreover, you may provide the 1st recessed part 31, the 2nd recessed part 32, and the 3rd recessed part 33 so that two or more may be arranged in one main surface or both main surfaces.
Even if a tuning fork type bending crystal resonator is configured as described above, the vibration leaking from the vibrating arm portion is attenuated, the propagation of the vibration to the supporting portion is reduced, and the deterioration of the temperature characteristic and the CI value is reduced. Can do.

Further modifications can be configured.
The tuning-fork type bending crystal resonator according to a further modification of the present invention is a component of the supporting arm portions 113 and 114 of the piezoelectric pieces 110a to 110l used in the first to seventh embodiments and each modification. The first support arm portion 113 and the second support arm portion 114 are extended from the base portion 111 in the opposite direction to the first vibration arm portion 112a and the second vibration arm portion which are the vibration arm portions 112. It is made out.
As an example, a piezoelectric piece 110m shown in FIG. 15 will be described.
The piezoelectric piece 110m includes a base 111, a first vibrating arm 112a and a second vibrating arm 112b extending from the base 111, the first vibrating arm 112a and the second vibrating arm 112b. Comprises a first support arm 113 and a second support arm 114 extending from the base in opposite directions.

Here, the base 111 has a length shorter than the entire width of the base 111, and the entire width of the base 111 is excluded except for a portion where the excitation electrodes 121a, 121b, 122a and 122b and the connection electrodes 123a and 123b are electrically connected. A groove-shaped second recess 32 is provided over the entire area.
First, the first support arm portion 113 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 113b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 113b. The third recess 33 has a length shorter than the entire width of the first extension 113a and is provided in a groove shape in the first extension 113a close to the vibrating arm 112 side. .
Further, the second support arm portion 114 has a length in which the first recess 31 is shorter than the entire width of the second extension portion 114b, and moves toward the vibrating arm portion 112 side so as to form a groove in the second extension portion 114b. The third recess 33 has a length shorter than the entire width of the first extension portion 114a and is provided in a groove shape in the first extension portion 114a so as to approach the vibrating arm portion 112 side. .

Note that the first recess 31 of the first support arm 113 and the first recess 31 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113b and 114b. May be provided at predetermined intervals.
Further, the third recess 33 of the first support arm 113 and the third recess 33 of the second support arm 114 do not face the front and back main surfaces of the respective second extending portions 113a and 114a. May be provided at predetermined intervals.
Thus, even if a further modification is configured, the propagation of vibration leaking from the vibrating arm portion 112 can be attenuated.

DESCRIPTION OF SYMBOLS 100 Tuning fork type bending crystal oscillator 31 1st recessed part 32 2nd recessed part 33 3rd recessed part 34 4th recessed part 110a-110m Piezoelectric piece 111 Base 112 Vibration arm part 112a First vibration arm part 112b Second vibration Arm 113 Support arm (first support arm)
113a 1st extension part 113b 2nd extension part 114 Support arm part (2nd support arm part)
114a 1st extension part 114b 2nd extension part

Claims (9)

A base, two pairs of vibrating arms extending from the base, and two pairs of supporting arms extending from the base along the vibrating arms,
The vibrating arm portion is configured to extend from the base portion inside the support arm portion provided in pairs,
The tuning fork-type bent quartz crystal resonator, wherein the support arm portion is configured to have a groove-shaped first recess in the width direction. The support arm portion is
2. The tuning fork-type bending crystal resonator according to claim 1, wherein the first concave portion is provided on the front and back main surfaces of the vibrating arm portion and is provided at a predetermined interval without facing each other. The support arm portion is
From a position away from the boundary between the base and the vibrating arm portion, it extends in a direction perpendicular to the extending direction of the vibrating arm portion and extends in parallel with the vibrating arm portion at a predetermined position. The tuning-fork type bending crystal resonator according to claim 1 or 2, wherein the tuning-fork type bending crystal resonator is configured. The base is
A groove-shaped second groove is formed between the boundary between the base and the vibrating arm and the boundary between the base and the supporting arm and is perpendicular to the extending direction of the vibrating arm. The tuning fork-type bent quartz crystal resonator according to claim 3, wherein the tuning-fork type bent crystal resonator is configured to have a concave portion. The base is
5. The tuning-fork type bent quartz crystal resonator according to claim 4, wherein the tuning fork type quartz crystal resonator is provided with a predetermined interval without facing each other while having the second concave portion on the front and back main surfaces of the base portion. The support arm portion is
The tuning fork-type bent quartz crystal according to any one of claims 1 to 5, wherein a groove-shaped third concave portion is formed in a width direction on a boundary side with the base portion. Vibrator. The support arm portion is
The tuning fork-type bent quartz crystal resonator according to claim 6, wherein the tuning fork-type bent quartz crystal resonator is provided with a predetermined interval without facing each other while having the third concave portion on the front and back main surfaces of the vibrating arm portion.   8. Each of the pair of vibrating arms is configured to have a groove-shaped fourth recess that is shorter than the vibrating arms. The tuning-fork type bending crystal resonator according to item.   2. Each of the pair of vibrating arm portions is configured to have a groove-shaped fourth recess that is arranged in two or more shorter than the vibrating arm portion. 8. A tuning-fork type bending crystal resonator according to any one of items 7 to 9.

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