JP6892988B2 - Tuning fork type crystal vibration element and tuning fork type crystal oscillator equipped with it - Google Patents

Description

The present invention relates to a tuning fork type crystal vibrating element that operates based on the piezoelectric effect of quartz and a tuning fork type crystal oscillator provided therewith.

A tuning fork-type crystal vibrating element having a pair of vibrating arms extending in parallel from the base of the base material and a tuning fork-type crystal oscillator having the same are known. A driving voltage is applied to the pair of vibrating arms to excite them. Such a tuning fork type crystal oscillator is used for a timing device, a vibration gyro sensor, or the like mounted on an electronic device such as a mobile computer, a portable game machine, a mobile phone, an IC card, or a communication base station. With the miniaturization and higher performance of electronic devices, tuning fork type crystal oscillators and tuning fork type crystal vibration elements built therein are required to have improved vibration characteristics and reliability.

For example, Patent Document 1 describes a tuning fork type including 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. Bent crystal oscillators are disclosed. Specifically, the vibrating arm portion is configured to extend from the base portion inside the support arm portion provided in pairs, and the support arm portion is configured to have a groove-shaped first recess in the width direction. Disclosed is a configuration in which the support arm portions are provided at predetermined intervals without facing each other while having the first concave portion on the front and back main surfaces of the vibrating arm portion. According to this, the vibration leaking from the vibrating arm portion to the supporting arm portion can be damped.

Japanese Unexamined Patent Publication No. 2011-015102

However, in the tuning fork type bent crystal oscillator described in Patent Document 1, the mechanical strength of the support arm portion is lowered by the groove-shaped first recess in the width direction. In particular, when the tuning fork type bending crystal vibrating element is mounted on the element connecting electrode pad of the element mounting member at the tip of the support arm and airtightly sealed by the lid, the element mounting portion or the lid is externally sealed by dropping or the like. The applied impact concentrates stress on the first recess when it is transmitted to the tuning fork type bent crystal unit. Therefore, the tuning fork type crystal oscillator may be damaged in the support arm portion due to the decrease in impact resistance caused by the first recess.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a tuning fork type crystal vibration element capable of improving vibration characteristics and suppressing deterioration of reliability.

The tuning fork type crystal vibrating element according to one aspect of the present invention has a base, a plurality of vibrating arms extending in the first direction from the base and arranging in a second direction intersecting the first direction, and from the base in the first direction. At least one support arm that extends and is provided outside the plurality of vibrating arms in the second direction, and at least one that is provided on at least one support arm and extends along the first direction. It has a hole.

The tuning fork type crystal oscillator according to another aspect of the present invention includes a base member, a lid member forming an internal space between the base members, a tuning fork type crystal vibrating element housed in the internal space, and a tuning fork type. The tuning fork type crystal vibrating element is provided with a conductive holding member that exciteably holds the crystal vibrating element to the base member, and the tuning fork type crystal vibrating element is arranged in the base and the second direction extending from the base in the first direction and intersecting the first direction. A plurality of vibrating arms, at least one supporting arm extending from the base in the first direction and provided outside the plurality of vibrating arms in the second direction, and at least one supporting arm. , At least one hole extending along the first direction and at least one support arm portion away from the base than at least one hole and fixed to the base member via a conductive holding member. It has a fixed part.

According to the present invention, it is possible to provide a piezoelectric vibration element capable of improving vibration characteristics and suppressing a decrease in reliability.

FIG. 1 is an exploded perspective view schematically showing the configuration of the tuning fork type crystal oscillator according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the configuration of the cross section of the tuning fork type crystal oscillator shown in FIG. 1 along the line II-II. FIG. 3 is a plan view schematically showing the configuration of the tuning fork type crystal vibrating element according to the first embodiment. FIG. 4 is a cross-sectional view schematically showing the configuration of the cross section of the tuning fork type crystal vibrating element shown in FIG. 3 along the IV-IV line. FIG. 5 is a cross-sectional view schematically showing the configuration of a cross section of the tuning fork type crystal vibrating element shown in FIG. 3 along the VV line. FIG. 6 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the second embodiment. FIG. 7 is a plan view schematically showing the configuration of the tuning fork type crystal vibrating element according to the third embodiment. FIG. 8 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the third embodiment. FIG. 9 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the fourth embodiment.

Hereinafter, embodiments of the present invention will be described with reference to the drawings. However, in the second and subsequent embodiments, the components that are the same as or similar to those of the first embodiment are represented by the same or similar reference numerals as those of the first embodiment, and detailed description thereof will be omitted as appropriate. Further, regarding the effects obtained in the second and subsequent embodiments, the same as those in the first embodiment will be omitted as appropriate. The drawings of each embodiment are examples, and the dimensions and shapes of each part are schematic, and the technical scope of the present invention should not be limited to the embodiment.

<First Embodiment>
First, the tuning fork type crystal vibrating element 10 and the tuning fork type crystal oscillator 1 provided with the tuning fork type crystal vibrating element 10 according to the first embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is an exploded perspective view schematically showing the configuration of the tuning fork type crystal oscillator according to the first embodiment. FIG. 2 is a cross-sectional view schematically showing the configuration of the cross section of the tuning fork type crystal oscillator shown in FIG. 1 along the line II-II. FIG. 3 is a plan view schematically showing the configuration of the tuning fork type crystal vibrating element according to the first embodiment.

In FIGS. 1 to 3, the excitation electrodes, connection electrodes, and other electrodes provided in the tuning fork type crystal vibration element 10 are not shown. Further, the first direction D1, the second direction D2, and the third direction D3 shown in the drawing are, for example, directions orthogonal to each other, but are not limited to these as long as they intersect each other. , They may intersect each other at an angle other than 90 °. The first direction D1, the second direction D2, and the third direction D3 mean the three reference directions shown in FIG. 1, respectively, in the positive direction (direction of the arrow) and the negative direction (opposite to the arrow). Direction) shall be included.

The tuning fork type crystal oscillator 1 is a kind of crystal oscillator (Quartz Crystal Resonator Unit). The tuning fork type crystal vibrating element 10 is a kind of crystal vibrating element (Quartz Crystal Resator), and is a crystal vibrating element in which an exciting portion that excites according to an applied voltage corresponds to a parallel arm portion in a tuning fork shape. The crystal vibrating element utilizes a crystal piece (Quartz Crystal Piece) that vibrates according to an applied voltage.

As shown in FIG. 1, the tuning fork type crystal oscillator 1 includes a tuning fork type crystal vibrating element 10, a lid member 20, a base member 30, and a joining member 40. The base member 30 and the lid member 20 are cages for accommodating the tuning fork type crystal vibrating element 10. In the example shown here, the lid member 20 has a concave shape, specifically, a box shape having an opening, and the base member 30 has a flat plate shape. The shapes of the lid member 20 and the base member 30 are not limited to the above, and for example, the base member may have a concave shape, and both the lid member and the base member have an opening on the side facing each other. It may be.

The tuning fork type crystal vibrating element 10 has a crystal piece 11. The crystal piece 11 is a tuning fork type Z plate crystal piece. Specifically, the Z-plate crystal piece is rotated clockwise around the Z-axis in a range of 0 to 5 degrees in a Cartesian coordinate system consisting of the X-axis, the Y-axis, and the Z-axis, and the X-axis and the Y-axis are rotated. A plane parallel to the plane specified by the axis (hereinafter referred to as "XY plane"; the same applies to a plane specified by another axis or another direction) is the main plane, and the direction parallel to the Z axis. Use the one obtained by cutting and polishing the artificial crystal so that the thickness becomes thick. The surface of the crystal piece 11 is not limited to the XY surface, and may be a surface inclined several degrees from the XY surface. The X-axis, Y-axis, and Z-axis are crystal axes of artificial crystals, respectively, and the X-axis corresponds to the electric axis, the Y-axis corresponds to the mechanical axis, and the Z-axis corresponds to the optical axis. The X-axis is a polar axis having a positive direction. Hereinafter, the direction parallel to the Y-axis is referred to as the Y-axis direction. The same applies to the other axial directions. As the crystal piece, a different cut other than the Z-plate crystal piece may be applied.

In the first embodiment, in the sound fork type crystal vibrating element 10, the Y axis is parallel to the first direction D1, the X axis is parallel to the second direction D2, and the Z axis is parallel to the third direction D3. Is located in. In the X-axis direction, which is the polar axis, the + X-axis direction is the positive direction of the second direction D2, and the −X-axis direction is the negative direction of the second direction D2. However, the first direction D1 may be along the Y-axis direction, and may be tilted in the range of −5 degrees to +5 degrees from the Y-axis direction, for example. Similarly, the second direction D2 may also be along the X-axis direction, and the third direction D3 may also be along the Z-axis direction.

As shown in FIGS. 1 and 3, the tuning fork type crystal vibrating element 10 composed of the crystal piece 11 of the Z plate has a base portion 50, a pair of vibrating arm portions 60, and a pair of supporting arm portions 70. Further, a plurality of holes 80 are formed in the pair of support arm portions 70.

The base portion 50 connects a pair of vibrating arm portions 60 at the end portion of the crystal piece 11 on the negative direction side of the first direction D1. Similarly, the base portion 50 also connects a pair of support arm portions 70. The base portion 50 has a front surface (first main surface) 50a on the side facing the lid member 20, and a back surface (second main surface) 50b on the side facing the base member 30.

The pair of vibrating arm portions 60 is a general term for the first vibrating arm portion 61 and the second vibrating arm portion 62 extending from the base portion 50 in the positive direction of the first direction D1 and lining up in the second direction D2. The first vibrating arm portion 61 is provided on the second direction D2 positive direction side of the second vibrating arm portion 62. Similar to the base 50, the pair of vibrating arm portions 60 also have a front surface (first main surface) 60a on the side facing the lid member 20, and a back surface (second main surface) on the side facing the base member 30. Has 60b. The first main surface 60a and the second main surface 60b of the pair of vibrating arm portions 60 are continuous with the first main surface 50a and the second main surface 50b of the base 50, respectively.

The first vibrating arm portion 61 and the second vibrating arm portion 62 are provided with a bottomed first groove 63a along the first direction D1 on the first main surface 60a, respectively, and the first direction is provided on the second main surface 60b. A bottomed second groove 63b along D1 is provided. The first groove 63a and the second groove 63b face each other in the third direction D3. By providing the first groove 63a and the second groove 63b in this way, the tuning fork type crystal vibrating element 10 improves the ease of movement of the first vibrating arm portion 61 and the second vibrating arm portion 62, and the first vibration. Vibration leakage from the arm 61 and the second vibrating arm 62 to the base 50 can be suppressed. The number of vibrating arms is not limited to two, and may be three or more.

The pair of support arms 70 extend from the base 50 in the positive direction D1 in the first direction, and the first support arms 71 and the second support arms provided outside the pair of vibrating arms 60 in the second direction D2. It is a generic term for unit 72. The first support arm portion 71 is provided on the second direction D2 positive direction side of the first vibrating arm portion 61, and the second support arm portion 72 is provided on the second direction D2 negative direction side of the second vibrating arm portion 62. Has been done. That is, the pair of vibrating arm portions 60 and the pair of supporting arm portions 70 are arranged in the second direction D2. Similar to the base 50, the pair of support arm portions 70 also have a front surface (first main surface) 70a on the side facing the lid member 20, and a back surface (second main surface) on the side facing the base member 30. It has 70b. The first main surface 70a and the second main surface 70b of the pair of support arm portions 70 are continuous with the first main surface 50a and the second main surface 50b of the base portion 50, respectively.

The length of the first support arm 71 and the second support arm 72 in the first direction D1 (hereinafter, simply referred to as “length”. The same applies to the first vibrating arm 61 and the second vibrating arm 62. ) Are substantially the same, and are shorter than the lengths of the first vibrating arm portion 61 and the second vibrating arm portion 62, respectively. Further, the lengths of the first support arm portion 71 and the second support arm portion 72 are about ½ of the lengths of the first vibrating arm portion 61 and the second vibrating arm portion 62, respectively. Fixing portions 76a and 76b fixed to the base member 30 are provided at the tip portions of the first support arm portion 71 and the second support arm portion 72, respectively. That is, the posture of the tuning fork type crystal vibrating element 10 is held via the fixing portions 76a and 76b. Since the fixing portions 76a and 76b are provided near the intermediate point in the first direction D1 of the tuning fork type crystal vibrating element 10, the posture of the tuning fork type crystal vibrating element 10 with respect to the base member 30 is stable, and the tuning fork type crystal vibrating element 10 It is possible to suppress deterioration of vibration characteristics due to contact with the lid member 20 or the base member 30.

The lengths of the first support arm 71 and the second support arm 72 are not particularly limited, and are 1/2 or less of the lengths of the first vibrating arm 61 and the second vibrating arm 62, respectively. It may be ½ or more of the length of the first vibrating arm portion 61 and the second vibrating arm portion 62. Further, the positions of the fixing portions 76a and 76b are not limited to the tip portions of the first supporting arm portion 71 and the second supporting arm portion 72. For example, when the lengths of the first support arm 71 and the second support arm 72 are the same as those of the first vibrating arm 61 and the second vibrating arm 62, respectively, the posture of the tuning fork type crystal vibrating element 10 It is desirable that the fixing portions 76a and 76b are provided in the intermediate portions of the first support arm portion 71 and the second support arm portion 72 in the first direction D1 in order to stabilize the above. The length of the first support arm portion 71 may be different from the length of the second support arm portion 72. Further, the position of the fixed portion 76a on the first support arm portion 71 may be different from the position of the fixed portion 76b on the second support arm portion 72. The number of supporting arms is not particularly limited and may be one. That is, either one of the first support arm portion 71 and the second support arm portion 72 may be omitted. The fixing portion may also be provided on the base portion 50.

A plurality of holes 80 are formed in the pair of support arm portions 70. The plurality of holes 80 extend along the first direction D1 and collectively refer to the groove-shaped first hole 81, the second hole 82, the third hole 83, and the fourth hole 84 that line up in the second direction D2. is there. The first hole 81 and the second hole 82 are bottomed grooves having openings on the first main surface 70a side of the first support arm portion 71. The first hole 81 and the second hole 82 are formed between the base portion 50 and the fixing portion 76a in the first support arm portion 71. The third hole 83 and the fourth hole 84 are bottomed grooves having openings on the first main surface 70a side of the second support arm portion 72. The third hole 83 and the fourth hole 84 are formed between the base portion 50 and the fixing portion 76b in the second support arm portion 72. The first hole 81 and the second hole 82 are formed in parallel, and the third hole 83 and the fourth hole 84 are formed in parallel.

The plurality of holes 80 may be formed from the pair of support arm portions 70 to the base portion 50. That is, the openings of the first hole 81 and the second hole 82 may extend from the first main surface 70a of the first support arm 71 to the first main surface 50a of the base 50. Similarly, the openings of the third hole 83 and the fourth hole 84 may extend from the first main surface 70a of the second support arm 72 to the first main surface 50a of the base 50. The positions of the first hole 81 and the second hole 82 are not particularly limited, and as will be described later, the first hole 81 and the second hole 82 may have an opening in the second main surface 70b of the first support arm portion 71. It may be a through hole having openings in the first main surface 70a and the second main surface 70b. Further, the first hole 81 and the second hole 82 may be displaced from each other in the first direction D1 or may be arranged in the first direction D1. The same applies to the third hole 83 and the fourth hole 84. The number of holes formed in the support arm is not particularly limited, and may be one per support arm or three or more per support arm. Further, the hole may be formed in one of the pair of supporting arms and may not be formed in the other.

The lid member 20 has a concave shape, and has a box shape that opens toward the first main surface 32a of the base member 30. The lid member 20 is joined to the base member 30 to provide an internal space 26 surrounded by the lid member 20 and the base member 30, and the tuning fork type crystal vibration element 10 is housed in the internal space 26. The shape of the lid member 20 is not particularly limited as long as it can accommodate the tuning fork type crystal vibrating element 10. For example, the lid member 20 has a rectangular shape when viewed in a plan view from the normal direction of the main surface of the top surface portion 21. ing. The lid member 20 has, for example, a long side parallel to the first direction D1, a short side parallel to the second direction D2, and a height parallel to the third direction D3. The material of the lid member 20 is not particularly limited, but is made of a conductive material such as metal. By including the conductive material, the lid member 20 can be provided with an electromagnetic shield function that shields the ingress and egress of electromagnetic waves into the internal space 26.

As shown in FIG. 2, the lid member 20 has an inner surface 24 and an outer surface 25. The inner surface 24 is a surface on the inner space 26 side, and the outer surface 25 is a surface on the opposite side to the inner surface 24. The lid member 20 is connected to the top surface portion 21 facing the first main surface 32a of the base member 30 and the outer edge of the top surface portion 21, and is a side wall extending in a direction intersecting the main surface of the top surface portion 21. It has a part 22 and. Further, the lid member 20 has a facing surface 23 facing the first main surface 32a of the base member 30 at the concave opening end portion (the end portion of the side wall portion 22 on the side closer to the base member 30). The facing surface 23 extends in a frame shape so as to surround the tuning fork type crystal vibrating element 10.

The base member 30 holds the tuning fork type crystal vibrating element 10 in an excitable manner. The base member 30 has a flat plate shape. The base member 30 has a long side parallel to the first direction D1 direction, a short side parallel to the second direction D2, and a thickness parallel to the third direction D3. The base member 30 has a base 31. The substrate 31 has a first main surface 32a (front surface) and a second main surface 32b (back surface) facing each other. The substrate 31 is a sintered material such as an insulating ceramic (alumina). The substrate 31 is preferably made of a heat resistant material.

The base member 30 has electrode pads 33a and 33b provided on the first main surface 32a and external electrodes 35a, 35b, 35c and 35d provided on the second main surface 32b. The electrode pads 33a and 33b are terminals for electrically connecting the base member 30 and the tuning fork type crystal oscillator 10. Further, the external electrodes 35a, 35b, 35c, 35d are terminals for electrically connecting a circuit board (not shown) and the tuning fork type crystal oscillator 1. The external electrodes 35a, 35b, 35c, and 35d are provided at the four corners of the base member 30, respectively. The external electrodes 35a and 35b to which the electric signal is input / output are arranged in the second direction D2 at the end of the base member 30 on the negative direction side of the first direction D1. The electrode pad 33a is electrically connected to the external electrode 35a via the via electrode 34a extending in the third direction D3, and extends in the first direction D1. The electrode pad 33b is electrically connected to the external electrode 35b via the via electrode 34b extending in the third direction D3, and extends in the first direction D1. The via electrodes 34a and 34b are formed in the via holes penetrating the substrate 31 in the third direction D3.

The external electrodes 35a and 35b may be provided at the central portion of the base member 30 in the first direction D1 so as to face the fixing portions 76a and 76b in the third direction D3, respectively. In this case, the via electrodes 34a and 34b are formed in the via holes penetrating the fixed portions 76a and 76b and the regions facing each other in the third direction D3, respectively. The external electrodes 35c and 35d may be dummy electrodes to which electric signals or the like are not input / output, or may be ground electrodes that supply a ground potential to the lid member 20 to improve the electromagnetic shield function of the lid member 20. The external electrodes 35c and 35d may be omitted.

The conductive holding members 36a and 36b are provided between the first main surface 32a of the base member 30 and the fixing portions 76a and 76b of the tuning fork type crystal vibration element 10. The conductive holding members 36a and 36b electrically connect the tuning fork type crystal vibration element 10 to the pair of electrode pads 33a and 33b of the base member 30. Further, the conductive holding members 36a and 36b hold the tuning fork type crystal vibrating element 10 to the base member 30 so as to be excited by fixing the fixing portions 76a and 76b to the first main surface 32a of the base member 30. .. The conductive holding members 36a and 36b are formed of, for example, a conductive adhesive containing a thermosetting resin, an ultraviolet curable resin, or the like, and are a filler or conductive material for maintaining a distance between the base member and the tuning fork type crystal vibrating element. It contains additives such as conductive particles for imparting conductivity to the holding member.

A sealing member 37 is provided on the first main surface 32a of the base member 30. In the example shown in FIG. 1, the sealing member 37 has a rectangular frame shape when viewed in a plan view from the normal direction of the first main surface 32a. When viewed in a plan view from the normal direction of the first main surface 32a, the electrode pads 33a and 33b are arranged inside the sealing member 37, and the sealing member 37 surrounds the tuning fork type crystal vibrating element 10. It is provided. The sealing member 37 is made of a conductive material. For example, by configuring the sealing member 37 with the same material as the electrode pads 33a and 33b, the sealing member 37 can be provided at the same time in the step of providing the electrode pads 33a and 33b.

The joining member 40 is provided over the entire circumference of each of the lid member 20 and the base member 30. Specifically, the joining member 40 is provided on the sealing member 37 and is formed in a rectangular frame shape. The sealing member 37 and the joining member 40 are sandwiched between the facing surface 23 of the side wall portion 22 of the lid member 20 and the first main surface 32a of the base member 30.

By joining the lid member 20 and the base member 30 with the sealing member 37 and the joining member 40 sandwiched between them, the tuning fork type crystal vibrating element 10 is surrounded by the lid member 20 and the base member 30. Cavity) 26 is sealed. The internal space 26 preferably has an atmospheric pressure lower than the atmospheric pressure, and more preferably a vacuum state. According to this, it is possible to reduce the time-dependent fluctuation of the frequency characteristics of the tuning fork type crystal oscillator 1 due to the oxidation of the first excitation electrode 91 and the second excitation electrode 92, which will be described later. The sealing member 37 may be provided in a discontinuous frame shape, or the joining member 40 may be provided in a discontinuous frame shape.

Next, the operation of the tuning fork type crystal vibration element 10 will be described with reference to FIG. FIG. 4 is a cross-sectional view schematically showing the configuration of the cross section of the tuning fork type crystal vibrating element shown in FIG. 3 along the IV-IV line. The IV-IV line is a line parallel to the second direction D2 passing through the fixed portion 76a of the first support arm portion 71 and the fixed portion 76b of the second support arm portion 72.

A first excitation electrode 91 and a second excitation electrode 92 are provided on the surfaces of the first vibrating arm portion 61 and the second vibrating arm portion 62, respectively. The first excitation electrode 91 is provided on both side surfaces of the first vibrating arm portion 61 and the second vibrating arm portion 62. Both side surfaces are a pair of side surfaces connecting the first main surface 60a and the second main surface 60b. That is, the first excitation electrode 91 faces each other so as to sandwich the first vibrating arm portion 61 and the second vibrating arm portion 62 in the second direction D2. The second excitation electrode 92 is provided inside each of the first groove 63a and the second groove 63b on the first main surface 60a and the second main surface 60b. The second excitation electrode 92 is also provided on the outside of the first groove 63a and the second groove 63b.

A first connection electrode 93 is provided on the second main surface 70b of the first support arm portion 71, and a second connection electrode 94 is provided on the second main surface 70b of the second support arm portion 72. The first connection electrode 93 electrically connects the first excitation electrode 91 and the conductive holding member 36a. Further, the second connection electrode 94 electrically connects the second excitation electrode 92 and the conductive holding member 36b.

The first excitation electrode 91 and the second excitation electrode 92 are electrodes made of, for example, a multi-layered metal film having nickel (Ni) or chromium (Cr) as a base layer and gold (Au) as the outermost layer. Since chromium has high adhesion to the crystal piece, it is possible to suppress peeling of the excitation electrode due to continuous operation for a long period of time or the like. Since gold has high chemical stability, it is possible to suppress fluctuations in vibration characteristics due to oxidation of the excitation electrode. The first connection electrode 93 and the second connection electrode 94 are provided with the same material as the first excitation electrode 91 and the second excitation electrode 92, respectively, and are integrated with the first excitation electrode 91 and the second excitation electrode 92 so as to be continuous with each other. Is formed. According to this, the first excitation electrode 91 and the second excitation electrode 92, and the first connection electrode 93 and the second connection electrode 94 can be formed at the same time by the same process.

The alternating magnetic field input from the electrode pad 33a and the electrode pad 33b is applied to the inside of the first vibrating arm portion 61 and the second vibrating arm portion 62 via the first exciting electrode 91 and the second exciting electrode 92, respectively. .. Then, each side surface of the first vibrating arm portion 61 and the second vibrating arm portion 62 expands and contracts based on the magnitude of the voltage of the alternating electric field. By applying an alternating electric field of a specific driving voltage between the first excitation electrode 91 and the second excitation electrode 92, the first vibrating arm portion 61 and the second vibrating arm portion 62 are formed into a pair of vibrating arms in FIG. It vibrates at a specific resonance frequency so as to approach or separate from each other in the direction of the arrow shown at the tip of the portion 60.

Next, with reference to FIG. 5, the functions of the plurality of holes 80 in the tuning fork type crystal vibrating element 10 will be described. FIG. 5 is a cross-sectional view schematically showing the configuration of a cross section of the tuning fork type crystal vibrating element shown in FIG. 3 along the VV line.

The plurality of holes 80 dampen the leaked vibration W that leaks from the pair of vibrating arms 60 and propagates through the base 50 and the pair of supporting arms 70. In particular, since the plurality of holes 80 have openings on the first main surface 70a side of the pair of support arm portions 70, the leakage vibration W that propagates on the first main surface 70a side is attenuated. From the viewpoint of the damping efficiency of the leakage vibration W, the depth of the plurality of holes 80 in the third direction D3 (hereinafter, simply referred to as “depth”; the same applies to the depths of other grooves and holes). Larger is preferred. If the plurality of holes 80 have the same depth as the first groove 63a of the pair of vibrating arms 60, the plurality of holes 80 and the first groove 63a can be formed at the same time by the same process.

<Second Embodiment>
Next, the configuration of the tuning fork type crystal vibration element 210 according to the second embodiment will be described with reference to FIG. FIG. 6 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the second embodiment. In each of the following embodiments, the matters common to those of the first embodiment will be omitted, and only the differences will be described. In particular, the same effects of the same configuration will not be mentioned sequentially. Further, the configuration with the same reference numerals as those in the first embodiment shall have the same configurations and functions as those in the first embodiment.

The tuning fork type crystal vibrating element 210 according to the second embodiment has the first embodiment in that the second hole 282 and the third hole 283 have an opening on the second main surface 270b side of the pair of support arm portions 270. It is different from the tuning fork type crystal vibration element 10. Further, the first hole 281 and the fourth hole 284 are deeper than the first groove 263a of the pair of vibrating arm portions 260, and the second hole 282 and the third hole 283 are deeper than the second groove 263b of the pair of vibrating arm portions 260. deep. A part of the first hole 281 and the second hole 282 face each other in the second direction D2. A part of the third hole 283 and the fourth hole 284 face each other in the second direction D2. The second hole 282 and the third hole 283 attenuate the leakage vibration W that propagates on the second main surface 270b side.

<Third Embodiment>
Next, the configuration of the tuning fork type crystal vibration element 310 according to the third embodiment will be described with reference to FIGS. 7 and 8. FIG. 7 is a plan view schematically showing the configuration of the tuning fork type crystal vibrating element according to the third embodiment. FIG. 8 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the third embodiment.

The tuning fork type crystal vibrating element 310 according to the third embodiment is different from the tuning fork type crystal vibrating element 10 according to the first embodiment in that a plurality of holes 380 extend in a direction intersecting the first direction D1. doing. Specifically, the first hole 381 extends in the fifth direction D5 inclined by an angle θ2 from the first direction D1 to the positive direction side of the second direction D2. The second hole 382 extends in the fourth direction D4 tilted by an angle θ1 from the first direction D1 to the negative direction side of the second direction D2. The angle θ1 and the angle θ2 are smaller than 45 degrees. The first hole 381 has an opening on the first main surface 370a side of the first support arm portion 371, and the second hole 382 has an opening on the second main surface 370b side. The first hole 381 and the second hole 382 are formed so as to intersect each other when viewed in a plan view from the normal direction of the first main surface 370a. The first hole 381 and the second hole 382 are separated from each other in the third direction D3 in the intersecting region. As a result, the decrease in rigidity of the first support arm portion 371 in the region where the first hole 381 and the second hole 382 intersect is suppressed. When the first hole 381 and the second hole 382 are connected in the intersecting region, the damping efficiency of the leakage vibration W can be improved. The first hole 381 and the second hole 382 may have openings on the same main surface side, or may be arranged side by side without intersecting in a plan view.

The third hole 383 and the fourth hole 384 are similarly formed. That is, the third hole 383 extends in the fifth direction D5 and has an opening on the second main surface 370b side. The fourth hole 384 extends in the fourth direction D4 and has an opening on the first main surface 370a side. The third hole 383 and the fourth hole 384 are also formed so as to intersect when viewed in a plan view from the normal direction of the first main surface 370a.

<Fourth Embodiment>
Next, the configuration of the tuning fork type crystal vibration element 410 according to the fourth embodiment will be described with reference to FIG. 9. FIG. 9 is a cross-sectional view schematically showing the configuration of the tuning fork type crystal vibrating element according to the fourth embodiment.

The tuning fork type crystal vibration element 410 according to the fourth embodiment is a tuning fork type crystal vibration element according to the first embodiment in that a plurality of holes 480 are through holes penetrating a pair of support arm portions 470 in the third direction D3. It is different from the element 10. That is, the first hole 481 and the second hole 482 have openings on both sides of the first main surface 470a and the second main surface 470b of the first support arm portion 471. The third hole 483 and the fourth hole 484 have openings on both sides of the first main surface 470a and the second main surface 470b of the second support arm portion 472. The plurality of holes 480 attenuate the leakage vibration W propagating through the pair of support arm portions 470 that propagates on both the first main surface 470a side and the second main surface 470b side.

As described above, according to one aspect of the present invention, the base portion 50, and the plurality of vibrating arm portions 60 extending from the base portion 50 in the first direction D1 and lining up in the second direction D2 intersecting the first direction D1. It extends from the base 50 to the first direction D1 and is provided on at least one support arm 70 and at least one support arm 70 provided outside the plurality of vibrating arm 60s in the second direction D2. Provided is a tuning fork-type crystal vibrating element 10 having at least one hole 80 extending along the first direction D1.

According to the above aspect, the hole formed in the support arm portion can attenuate the leaking vibration that leaks from the vibrating arm portion and propagates through the support arm portion. Further, since the hole is formed along the extending direction of the support arm portion, it is possible to suppress the decrease in the rigidity of the support arm portion due to the hole.

At least one hole 80 may be a groove having a bottom surface, in other words, a recess. According to this, it is possible to suppress a decrease in the rigidity of the support arm portion due to the hole.

At least one hole 480 may be a through hole. According to this, the hole can more efficiently attenuate the leakage vibration W propagating in the support arm portion.

Further comprising a fixing portion 76a provided on at least one support arm 70, the fixing portion 76a may be more distant from the base 50 than at least one hole 80. According to this, when the tuning fork type crystal oscillator is displaced with respect to the cage due to the impact of dropping, stress is concentrated in the hole of the support arm, but the hole is formed along the extension direction of the support arm. Therefore, it is possible to suppress damage to the support arm portion due to the hole. Further, since the posture of the tuning fork type crystal vibration element when mounted on the base member can be stabilized, the interference of the tuning fork type crystal vibration element with the base member or the lid member is reduced, and the deterioration of the vibration characteristics is suppressed. be able to.

At least one hole 380 may extend in directions D4 and D5 intersecting the first direction D1 at angles θ1 and θ2 smaller than 45 degrees. According to this, the hole can more efficiently attenuate the leakage vibration W propagating in the support arm portion.

At least one hole 80 may extend in a direction parallel to the first direction D1. According to this, it is possible to suppress a decrease in the rigidity of the support arm portion due to the hole.

The at least one hole 80 may have a plurality of holes 81, 82 aligned in the second direction D2 in one of the at least one support arm 70. According to this, the hole can more efficiently attenuate the leakage vibration W propagating in the support arm portion.

The at least one hole 280 is a first hole 281 having an opening in one main surface 270a of the at least one support arm 270 and the other main surface 270b in one of the at least one support arm 270. It may have a second hole 282 having an opening in the hole 282. According to this, the hole can more efficiently attenuate the leakage vibration W propagating in the support arm portion.

According to another aspect of the present invention, the base member 30, the lid member 20 forming the internal space 26 between the base member 30, the tuning fork type crystal vibrating element 10 housed in the internal space 26, and the tuning fork. The tuning fork type crystal vibrating element 10 includes a conductive holding member 36a that vibrates and holds the type crystal vibrating element 10 to the base member 30, and the tuning fork type crystal vibrating element 10 extends from the base 50 to the first direction D1 and extends in the first direction. A plurality of vibrating arm portions 60 arranged in the second direction D2 intersecting with D1, and at least one provided from the base portion 50 to the first direction D1 and provided outside the plurality of vibrating arm portions 60 in the second direction D2. One support arm 70, at least one hole 80 provided in at least one support arm 70 and extending along the first direction D1, and at least one more away from the base 50 than at least one hole 80. Provided is a tuning fork type crystal oscillator 1 provided on one support arm 70 and including a fixing portion 76a fixed to a base member 30 via a conductive holding member 36a.

According to the above aspect, the hole formed in the support arm portion can attenuate the leaking vibration that leaks from the vibrating arm portion and propagates through the support arm portion. That is, it is possible to suppress vibration leakage to the base member. Further, since the hole is formed along the extending direction of the support arm portion, it is possible to suppress the decrease in the rigidity of the support arm portion due to the hole. That is, it is possible to suppress damage to the support arm portion due to the stress applied to the support arm portion being concentrated in the hole.

As described above, according to one aspect of the present invention, it is possible to provide a tuning fork type crystal vibration element capable of improving the vibration characteristics and suppressing the decrease in reliability.

It should be noted that the embodiments described above are for facilitating the understanding of the present invention, and are not for limiting and interpreting the present invention. The present invention can be modified / improved without departing from the spirit of the present invention, and the present invention also includes an equivalent thereof. That is, those skilled in the art with appropriate design changes to each embodiment are also included in the scope of the present invention as long as they have the features of the present invention. For example, each element included in each embodiment and its arrangement, material, condition, shape, size, and the like are not limited to those exemplified, and can be changed as appropriate. In addition, the elements included in each embodiment can be combined as much as technically possible, and the combination thereof is also included in the scope of the present invention as long as the features of the present invention are included.

1 ... Tuning fork type crystal oscillator 10 ... Tuning fork type crystal vibrating element 11 ... Crystal piece 30 ... Base member 40 ... Joining member 50 ... Base 60 ... Pair of vibrating arms 61 ... First vibrating arm 62 ... Second vibrating arm 70 ... A pair of support arms 71 ... 1st support arm 72 ... 2nd support arm 76a ... Fixed part 80 ... Multiple holes 81 ... 1st hole 82 ... 2nd hole 83 ... 3rd hole 84 ... 4th hole W ... Leakage vibration

Claims (9)

At the base,
A plurality of vibrating arms extending in the first direction from the base and lining up in the second direction intersecting the first direction.
At least one support arm portion extending from the base portion in the first direction and provided outside the plurality of vibrating arm portions in the second direction.
With at least one hole provided in the at least one support arm and extending along the first direction.
A tuning fork-type crystal oscillator whose at least one hole extends in a direction intersecting the first direction at an angle smaller than 45 degrees. At the base,
A plurality of vibrating arms extending in the first direction from the base and lining up in the second direction intersecting the first direction.
At least one support arm portion extending from the base portion in the first direction and provided outside the plurality of vibrating arm portions in the second direction.
With at least one hole provided in the at least one support arm and extending along the first direction.
Wherein said at least one hole, the have a plurality of holes arranged in the second direction in one of the at least one support arm portion,
Further provided with a fixing portion provided on the at least one support arm portion,
The fixed portion is a tuning fork type crystal vibrating element that is separated from the base portion by the at least one hole. The at least one hole is a groove having a bottom.
The tuning fork type crystal vibrating element according to claim 1 or 2. The at least one hole is a through hole.
The tuning fork type crystal vibrating element according to claim 1 or 2. Further provided with a fixing portion provided on the at least one support arm portion,
The fixing portion is separated from the base portion by the at least one hole.
The tuning fork type crystal vibrating element according to claim 1. The at least one hole extends in a direction parallel to the first direction.
The tuning fork type crystal vibrating element according to claim 2. The at least one hole is a first hole having an opening on one main surface of the at least one support arm portion and an opening on the other main surface in one of the at least one support arm portions. With a second hole with
The tuning fork type crystal vibrating element according to any one of claims 1 to 6. With the base member
A lid member that forms an internal space between the base member and
The tuning fork type crystal vibrating element housed in the internal space and
The tuning fork type crystal vibrating element is provided with a conductive holding member that holds the tuning fork type crystal vibrating element in an excitable manner in the base member.
The tuning fork type crystal vibrating element is
At the base,
A plurality of vibrating arms extending in the first direction from the base and lining up in the second direction intersecting the first direction.
At least one support arm portion extending from the base portion in the first direction and provided outside the plurality of vibrating arm portions in the second direction.
With at least one hole provided in the at least one support arm and extending along the first direction.
The support arm portion is provided with the support arm portion so as to be separated from the base portion by the at least one hole, and is provided with a fixing portion fixed to the base member via the conductive holding member.
A tuning fork type crystal oscillator in which the at least one hole extends in a direction intersecting the first direction at an angle smaller than 45 degrees. With the base member
A lid member that forms an internal space between the base member and
The tuning fork type crystal vibrating element housed in the internal space and
The tuning fork type crystal vibrating element is provided with a conductive holding member that holds the tuning fork type crystal vibrating element in an excitable manner in the base member.
The tuning fork type crystal vibrating element is
At the base,
A plurality of vibrating arms extending in the first direction from the base and lining up in the second direction intersecting the first direction.
At least one support arm portion extending from the base portion in the first direction and provided outside the plurality of vibrating arm portions in the second direction.
With at least one hole provided in the at least one support arm and extending along the first direction.
The support arm portion is provided with the support arm portion so as to be separated from the base portion by the at least one hole, and is provided with a fixing portion fixed to the base member via the conductive holding member.
The at least one hole is a tuning fork type crystal oscillator having a plurality of holes arranged in the second direction in one of the at least one support arm portion.

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