JP2010119148A - Piezoelectric vibrator - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide: a tuning-fork type piezoelectric vibrator piece preventing a package for mounting the tuning-fork type piezoelectric vibrator piece thereon from colliding with a vibrating arm even if a shock is applied to the tuning-fork type piezoelectric vibrator piece; and a method of mounting the same. <P>SOLUTION: This piezoelectric vibrator is formed by housing this tuning-fork type piezoelectric vibrator piece in a package. The tuning-fork type piezoelectric vibrator piece includes: a tuning-fork type piezoelectric vibrator piece body having a plurality of vibrating arms; a first short-side part formed along a direction intersecting a direction in which the vibrating arms extends and connected to the piezoelectric vibrator piece body; a long-side part formed along the direction in which the vibrating arms extends from the first short-side part up to the front side relative to the tips of the vibrating arms toward the direction in which the vibrating arms extends; and a second short-side part formed by extending the tip of the long-side part along the direction intersecting the direction in which the vibrating arms extend on the front side relative to the tips of the vibrating arms. The undersurface of the second short-side part is fixed to the package. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a piezoelectric vibrator, and more particularly to a piezoelectric vibrator suitable for preventing a resonator element from being damaged by an impact.

  The surface mount type tuning fork type piezoelectric vibrating piece includes a structure in which a vibrating arm extends from one end of a base, or a tuning fork type piezoelectric vibrating piece main body in which a vibrating arm extends from one end of a base and a tuning fork connected to the base. There is a structure composed of a supporting portion that surrounds the main body of the piezoelectric piezoelectric resonator element in a frame shape. 4 and 5 are explanatory views of a tuning fork type piezoelectric vibrating piece according to the prior art. 4 (a) and 5 (a) are plan views of the tuning fork type piezoelectric vibrating piece, and FIGS. 4 (b) and 5 (b) are cross-sectional views when the tuning fork type piezoelectric vibrating piece is mounted on a package. When the tuning fork-type piezoelectric vibrating piece 112 including the base 110 and the vibrating arm 111 is mounted on the package 113, the connection electrode provided on the back surface of the base 110 and the package-side mount electrode 114 provided on the package 113 are conductively bonded. It is bonded and fixed via the agent 115 (see FIG. 4). When the tuning fork type piezoelectric vibrating piece main body 122 including the base 120 and the vibrating arm 121 and the tuning fork type piezoelectric vibrating piece 124 including the supporting portion 123 surrounding the tuning fork type piezoelectric vibrating piece main body 122 in a frame shape are mounted on the package 125, The connection electrodes provided at both ends in the longitudinal direction of the support portion 123 and the package side mount electrodes 126 provided in the package are bonded and fixed via a conductive adhesive 127 (see FIG. 5).

  Further, there is a tuning fork type piezoelectric vibrating piece having a structure including a base, a vibrating arm, and an L-shaped branch projecting from the base (Patent Document 1). In addition, a case is joined to the support portion of the tuning fork type piezoelectric vibrating piece composed of a tuning fork type piezoelectric vibrating piece body and a supporting portion surrounding the tuning fork type piezoelectric vibrating piece body in a frame shape via solder materials from above and below. There is a structure of a tuning fork type piezoelectric vibrator (Patent Document 2).

JP-A-57-185717 JP 54-58395 A

  By the way, since the tuning fork type piezoelectric vibrating piece including the base and the vibrating arm is supported only at two places with the package, the tuning fork type piezoelectric vibrating piece may not be mounted parallel to the bottom surface of the package. That is, there is a problem in that the tuning fork type piezoelectric vibrating piece is inclined upward or downward as compared with the case where the tip side is mounted in parallel, resulting in variations in mounting. Moreover, when the tuning fork type piezoelectric vibrating piece consisting of the base and the vibrating arm is supported only at two places with the package, and when the tuning fork type piezoelectric vibrating piece consisting of the base, the vibrating arm and the supporting part is mounted as described above, dropping, etc. When a strong impact due to is applied to the tuning fork type piezoelectric vibrating piece, the tip of the vibrating arm may collide with the package. Due to this collision, there is a problem that breakage or chipping of the vibrating arm occurs, and the frequency characteristics of the tuning fork type piezoelectric vibrating piece deteriorate. In particular, in recent years, the tuning fork type piezoelectric vibrating piece has been reduced in size and thickness, so that there has been a problem that it is vulnerable to impact.

  The tuning fork type piezoelectric vibrating piece described in Patent Document 1 does not describe mounting on a package, and there is no place for absorbing a shock or the like in the tuning fork type vibrating piece. Further, in the tuning fork type piezoelectric vibrating piece described in Patent Document 2, since the support portion is sandwiched between the cases as described above, there is no place to absorb the impact.

  The present invention has been made to solve the above problems, and provides a piezoelectric vibrator that can be mounted parallel to the bottom surface of a package and that can prevent a vibrating arm from colliding with the package. With the goal.

  In order to achieve the above object, a piezoelectric vibrator according to the present invention is a piezoelectric vibrator in which a tuning fork type piezoelectric vibrating piece is accommodated in a package, and the tuning fork type piezoelectric vibrating piece has a plurality of vibrating arms. A piezoelectric vibrating reed body, a first short side part formed along a direction intersecting with the extending direction of the vibrating arm, and connected to the piezoelectric vibrating piece body, and the vibrating arm extends from the first short side part. A long side portion formed along a direction in which the vibrating arm extends from the tip of the vibrating arm toward the direction, and a tip of the long side portion of the vibrating arm before the tip of the vibrating arm. And a second short side portion formed so as to extend along a direction intersecting with the extending direction, and a lower surface of the second short side portion is fixed to the package. When an impact is applied to the piezoelectric vibrator, the impact can be reduced by vibrating up and down while the long side portion becomes an impact relaxation portion and curves. For this reason, the tuning fork type piezoelectric vibrating reed main body is not vibrated vigorously and only moves up and down slightly, so that it does not collide with the package. Therefore, it is possible to prevent the tuning fork type piezoelectric vibrating reed body from colliding with the package.

  The plurality of resonating arms include a pair of resonating arms, and the long side portion is between the pair of resonating arms and the resonating arm extends in a direction in which the resonating arm extends from the first short side portion. It is characterized by being formed beyond the tip. As a result, when an impact is applied, the long side portion is preferentially curved as an impact relaxation portion, and the displacement of the tuning fork type piezoelectric vibrating piece itself is suppressed, thus preventing the tuning fork type piezoelectric vibrating piece from colliding with the package. can do. In addition, since the vibration leaking from the vibrating arm can be attenuated at the long side portion, a piezoelectric vibrator having excellent vibration characteristics can be obtained.

  The plurality of resonating arms include a pair of resonating arms, and the long side portion is outside the pair of resonating arms, and the resonating arm extends in a direction in which the resonating arm extends from the first short side portion. Including a first long side portion and a second long side portion formed from the tip end to the tip end side of the vibrating arm. The second short sides are connected to each other. Since the frame portion is formed by the first and second short side portions and the first and second long side portions, the frame portion can be mounted when the tuning fork type piezoelectric vibrating piece is mounted on the package base. . When an impact is applied to the tuning fork type piezoelectric vibrating piece, the long side portion becomes an impact relaxation portion and vibrates up and down while curving, so that the impact can be reduced. Since the tuning fork type piezoelectric vibrating piece main body only slightly moves up and down, it is possible to prevent the tuning fork type piezoelectric vibrating piece main body from colliding with the package.

  Further, the long side portion may be an impact relaxation portion formed by providing a hole or a recess. Even if an impact is applied to the tuning fork type piezoelectric vibrating piece by designing the thickness and thickness of the impact relaxation part, the size of the hole or the recess, etc. according to the size and position of the center of gravity of the tuning fork type piezoelectric vibrating piece, This impact can be mitigated by the impact mitigating portion.

  Further, the distance between the vibrating arm and the long side portion may be wider than an amplitude at which the vibrating arm vibrates when an impact is applied to the piezoelectric vibrator. The mount portion is positioned closer to the tip side of the vibrating arm than the center of gravity of the tuning fork type piezoelectric vibrating piece. Therefore, the impact applied to the tuning fork type piezoelectric vibrating piece can be mitigated at the long side portion, and the tuning fork type piezoelectric vibrating piece body can be prevented from colliding with the package. The vibrating arm does not collide with the long side portion and damage such as cracks or chipping occurs. Further, since the tuning fork type piezoelectric vibrating piece does not have a base portion, it can be miniaturized.

It is explanatory drawing of the tuning fork type piezoelectric vibrating piece and tuning fork type piezoelectric vibrator which concern on 1st related embodiment. It is explanatory drawing of the tuning fork type piezoelectric vibrating piece and tuning fork type piezoelectric vibrator which concern on 2nd related embodiment. It is a figure explaining the modification of the tuning fork type piezoelectric vibrating piece which concerns on 2nd related embodiment. It is explanatory drawing of the tuning fork type piezoelectric vibrating piece which has a base and a vibrating arm in connection with the prior art. It is explanatory drawing of the tuning fork type piezoelectric vibrating piece which has a base part, a vibrating arm, and a support part according to the prior art. It is a graph which shows the result of an impact test. It is a figure explaining the modification of the tuning fork type piezoelectric vibrator which concerns on 2nd related embodiment. It is explanatory drawing of the tuning fork type piezoelectric vibrating piece which concerns on embodiment of this invention. It is explanatory drawing of the tuning fork type piezoelectric vibrating piece and tuning fork type piezoelectric vibrator which concern on 3rd related embodiment. It is explanatory drawing of the groove | channel provided in a vibrating arm. It is explanatory drawing of an impact relaxation part.

  Hereinafter, embodiments of the piezoelectric vibrator according to the present invention will be described. In addition, what is described below is only one embodiment of the present invention, and the present invention is not limited to this. First, an embodiment related to the present invention will be described. FIG. 1 is an explanatory diagram of a tuning fork type piezoelectric vibrating piece and a tuning fork type piezoelectric vibrator according to a first related embodiment. FIG. 1A is a plan view of a tuning fork type piezoelectric vibrating piece, FIG. 1B is a cross-sectional view of the tuning fork type piezoelectric vibrator, and FIG. 1C shows an impact applied to the tuning fork type piezoelectric vibrator. It is explanatory drawing which a vibration piece eases.

  The tuning fork type piezoelectric vibrating piece 10 has a tuning fork type piezoelectric vibrating piece main body 16 in which a vibrating arm 14 extends from one end of a base 12. The tuning fork type piezoelectric vibrating piece main body 16 includes a short side portion 18 along a direction intersecting with a longitudinal direction of the tuning fork type piezoelectric vibrating piece main body 16, and a longitudinal direction of the tuning fork type piezoelectric vibrating piece main body 16 from both ends of the short side portion 18. The impact relaxation part 22 which consists of the long side part 20 formed along is connected. The interval between the vibrating arm 14 and the long side portion 20 is formed wider than the amplitude in the left-right direction in which the vibrating arm 14 vibrates when an impact is applied to the tuning fork type piezoelectric vibrating piece 10.

  The long side portion 20 is formed with a mount portion 26 for mounting the tuning fork type piezoelectric vibrating piece 10 to the package base 24. The mount portion 26 is provided corresponding to the position of the center of gravity of the tuning fork type piezoelectric vibrating piece 10 in the longitudinal direction, and a connection electrode (not shown) is formed on the lower surface of the mount portion 26. The mount portion 26 is preferably provided on the distal end side of the vibrating arm 14 with respect to the position of the center of gravity of the tuning fork type piezoelectric vibrating piece 10 including the tuning fork type piezoelectric vibrating piece main body 16, the short side portion 18 and the long side portion 20. In the present embodiment, the mount portion 26 is provided at the tip of the long side portion 20, but it is not always necessary to provide it at the tip.

Further, the impact relaxation portion 22 positioned on the base 12 side from the mount portion 26 has a function of reducing the impact when the impact is applied to the tuning fork type piezoelectric vibrating piece 10 by adjusting the thickness and width.
Excitation electrodes (not shown) are formed on the upper and lower surfaces of the tuning-fork type piezoelectric vibrating reed body 16, and the excitation electrode and the connection electrode are electrically connected to each other by an extraction electrode (not shown) provided in the impact relaxation portion 22. It has become.

  In the tuning fork type piezoelectric vibrating piece 10 having such a configuration, the connection electrode provided on the mount portion 26 and the package side mount electrode 28 provided on the package base 24 are bonded and fixed by the bonding material 30. To be implemented. As the bonding material 30, a conductive adhesive, a conductive sheet, a conductive film, a gold bump, a gold-tin alloy brazing material, or the like is used. In particular, when a silicone-based conductive adhesive is used, heat resistance is improved and gas generated from the conductive adhesive can be suppressed. Further, when gold bumps are used, no gas is generated, which is suitable for vacuum-sealing the package 32. In addition, when desired electrical conductivity is not obtained, you may make it obtain electroconductivity via a bonding wire. Then, a lid 34 is joined to the upper end surface of the package base 24 via a low melting point glass or by seam welding to constitute a tuning fork type piezoelectric vibrator 36.

  Next, the operation of the tuning fork type piezoelectric vibrating piece 10 when an impact due to dropping or the like is applied to the tuning fork type piezoelectric vibrator 36 will be described. When an impact is applied to the tuning fork type piezoelectric vibrator 36, the impact is propagated to the tuning fork type piezoelectric vibrating piece 10. The tuning-fork type piezoelectric vibrating piece 10 vibrates due to an impact, but the impact mitigating portion 22 having a function of mitigating the impact mainly vibrates. That is, when an impact is applied to the tuning-fork type piezoelectric vibrating piece 10, the impact relaxation portion 22 vibrates up and down while curving around the mount portion 26 to relax the impact. At this time, the tuning fork type piezoelectric vibrating reed body 16 only moves up and down while being parallel to the bottom surface of the package base 24, so that the tuning fork type piezoelectric vibrating reed body 16 does not collide with the package 32 (FIG. 1 (c). )reference). Further, the vibrating arm 14 and the long side portion 20 do not collide.

  In such a configuration, the impact forcing portion 22 of the tuning fork type piezoelectric vibrating piece 10 has a function to reduce the impact, so that even when an impact is applied to the tuning fork type piezoelectric vibrator 36, the tuning fork type piezoelectric vibrating piece 10. Does not collide with the package 32 and cause breakage, chipping or the like. Further, even if the tuning fork type piezoelectric vibrating piece is reduced in size and thickness, damage due to collision does not occur. For this reason, the frequency characteristic etc. do not change with an impact, and the highly reliable tuning fork type piezoelectric vibrating piece 10 can be provided.

  Further, since the impact relaxation unit 22 has a function of relaxing impact, that is, vibration, it is possible to attenuate vibration leakage that propagates from the bending vibration of the tuning fork type piezoelectric vibrating piece 10. For this reason, the crystal impedance value can be reduced, and the tuning fork type piezoelectric vibrator 36 having excellent vibration characteristics can be obtained.

Further, the distance between the vibrating arm 14 and the long side portion 20 has a distance that does not collide with the long side portion 20 even if the vibrating arm 14 swings left and right when an impact is applied to the tuning fork type piezoelectric vibrating piece 10. The vibrating arm 14 and the long side portion 20 do not collide and cause damage such as chipping or cracking.
A tuning fork type piezoelectric oscillator and a real time clock can be formed using the tuning fork type piezoelectric vibrating piece 10 described above.

  In the present embodiment, the long side portion 20 is provided with the mount portion 26, but one long side portion 20 is provided with one mount portion, and the other long side portion 20 is provided with two mount portions. It can also be configured. Further, it is possible to provide a structure in which two or more mount portions are provided on the long side portion 20 on one side, and four or more mount portions are provided as a whole. With such a configuration, the package base 24 can be mounted so as to be surely parallel to the bottom surface.

  Next, a second related embodiment will be described. 2A is a plan view of the tuning-fork type piezoelectric vibrating piece, FIG. 2B is a cross-sectional view of the tuning-fork type piezoelectric vibrator, and FIG. 2C is a tuning fork type piezoelectric vibrator. It is explanatory drawing which a vibration piece eases. The tuning fork type piezoelectric vibrating piece 50 has a tuning fork type piezoelectric vibrating piece main body 56 in which a vibrating arm 54 extends from one end of a base 52. The tuning fork type piezoelectric vibrating piece main body 56 includes a short side portion 57 along a direction intersecting with a longitudinal direction of the tuning fork type piezoelectric vibrating piece main body 56, and a longitudinal direction of the tuning fork type piezoelectric vibrating piece main body 56 from both ends of the short side portion 57. The impact relaxation part 72 which consists of the long side part 58 formed along is connected. A support portion 59 is connected to the distal end side of the vibrating arm 54 of the long side portion 58 along the direction intersecting with the longitudinal direction of the tuning fork type piezoelectric vibrating piece main body 56. The support portion 59 and the impact relaxation portion 72 surround the tuning fork type piezoelectric vibrating piece main body 56.

  Each of the long side portions 58 is provided with a mount portion, and a connection electrode (not shown) used when the tuning fork type piezoelectric vibrating piece 50 is mounted on the package base 60 is formed on the lower surface of the mount portion. The mount portion provided with the connection electrode is provided closer to the vibrating arm 54 than the position of the center of gravity in the longitudinal direction of the tuning fork type piezoelectric vibrating piece 50 (the tip side of the vibrating arm 54). The connection electrode is electrically connected via an excitation electrode (not shown) provided on the tuning-fork type piezoelectric vibrating piece main body 56 and an extraction electrode (not shown) provided on the impact relaxation portion 72. The support portion 59 serves as a mount portion for mounting the tuning fork type piezoelectric vibrating piece 50 on the package base 60. A plurality of mount portions may be provided on the long side portion 58 on the distal end side of the vibrating arm 54 with respect to the connection electrode.

  The interval between the vibrating arm 54 and the long side portion 58 is formed wider than the amplitude in the left-right direction in which the vibrating arm 54 vibrates when an impact is applied to the tuning-fork type piezoelectric vibrating piece 50. Further, the thickness and width of the impact relaxation portion 72 are adjusted, and the impact relaxation portion 72 has a function of relaxing the impact when an impact is applied to the tuning fork type piezoelectric vibrating piece 50.

  In the tuning fork type piezoelectric vibrating piece 50 having such a configuration, the connection electrode provided on the long side portion 58 and the package side mount electrode 62 provided on the package base 60 are bonded and fixed by a bonding material 64. Further, the lower surface of the support portion 59 is bonded and fixed to the package base 60 via a bonding material 64. When the support portion 59 and the package base 60 are joined, the joining material 64 may be applied and joined to two places on both ends of the lower surface of the support portion 59, and the joining material 64 may be joined to one place on the entire lower surface of the support portion 59. May be applied and bonded. A conductive adhesive, a conductive sheet, a conductive film, a gold bump, a gold-tin alloy brazing material, or the like is used as the bonding material 64 for bonding the connection electrode and the package side mount electrode 62. In particular, when a silicone-based conductive adhesive is used, heat resistance is improved and gas generated from the conductive adhesive can be suppressed. Further, when gold bumps are used, no gas is generated, which is suitable for vacuum-sealing the package 66. In addition, when desired electrical conductivity is not obtained, you may make it obtain electroconductivity via a bonding wire. Further, the bonding material described above can be used as the bonding material 64 for bonding the support portion 59 and the package base 60, and a bonding material having no conductivity can also be used. Then, a lid 68 is joined to the upper end surface of the package base 60 via a low melting point glass or by seam welding to constitute a tuning fork type piezoelectric vibrator 70.

  Next, the operation of the tuning fork type piezoelectric vibrating piece 50 when an impact due to dropping or the like is applied to the tuning fork type piezoelectric vibrator 70 will be described. When an impact is applied to the tuning fork type piezoelectric vibrator 70, the impact is propagated to the tuning fork type piezoelectric vibrating piece 50. Then, since the impact relaxation portion 72 has a function of relaxing the impact, the impact relaxation portion 72 vibrates up and down while curving around the position of the connection electrode. By this vibration, the impact transmitted to the tuning fork type piezoelectric vibrating piece 50 is alleviated. For this reason, since the tuning fork type piezoelectric vibrating piece 50 only moves the tip of the vibrating arm 54 slightly up and down, the tuning fork type piezoelectric vibrating piece main body 56 does not collide with the package 66 (see FIG. 2C). Further, the vibrating arm 54 and the long side portion 58 do not collide.

  In such a configuration, the shock relaxation unit 72 of the tuning fork type piezoelectric vibrating piece 50 has a function of buffering the impact. Therefore, even when an impact is applied to the tuning fork type piezoelectric vibrator 70, the shock relaxation unit 72 applies the shock. The tuning fork type piezoelectric vibrating reed main body 56 is not vigorously shaken. For this reason, the tuning fork type piezoelectric vibrating piece 50 does not collide with the package 66 and damage such as cracking or chipping occurs. Further, the tuning fork type piezoelectric vibrating piece has a function of mitigating the impact, so that the tuning fork type piezoelectric vibrating piece is not damaged even if the tuning fork type piezoelectric vibrating piece is reduced in size and thickness. Further, the tuning fork type piezoelectric vibrating piece 50 can be provided with high reliability without changing frequency characteristics and the like due to impact.

  Further, the impact relaxation unit 72 can also attenuate the vibration leakage that propagates from the bending vibration of the tuning fork type piezoelectric vibrating piece 50. For this reason, the crystal impedance value is reduced, and the tuning fork type piezoelectric vibrator 70 having excellent vibration characteristics can be obtained.

  Further, the distance between the vibrating arm 54 and the long side portion 58 is a distance that does not collide with the long side portion 58 even if the vibrating arm 54 swings left and right when an impact is applied to the tuning fork type piezoelectric vibrating piece 50. The vibrating arm 54 and the long side portion 58 do not collide and cause damage such as chipping or cracking.

  Further, by providing the mount portion provided on the long side portion 58 closer to the vibrating arm 54 than the longitudinal center of gravity of the tuning-fork type piezoelectric vibrating piece 50, the displacement on the base 52 side occurs preferentially and an impact is applied. In this case, the amount of displacement of the tuning fork type piezoelectric vibrating piece 50 itself is suppressed, and the tuning fork type piezoelectric vibrating piece 50 does not collide with the package and generate cracks or chips.

In addition, the tuning fork type piezoelectric vibrating piece 50 according to the second embodiment is formed with a frame portion surrounding the tuning fork type piezoelectric vibrating piece 50, so that the tuning fork type piezoelectric vibrating piece 50 does not have this frame portion. The mechanical strength can be improved.
A tuning fork type piezoelectric oscillator and a real time clock can be formed using the tuning fork type piezoelectric vibrating piece 50 described above.

  Next, an impact test of the tuning fork type piezoelectric vibrator 70 will be described. For this impact test, the tuning fork type piezoelectric vibrator 70 described above and a tuning fork type piezoelectric vibrator according to the prior art which does not include the impact relaxation portion 72 were used. In the impact test, the tuning fork type piezoelectric vibrator was set on a jig and then dropped from the height of 150 cm 10 times in the length, width and height directions of the tuning fork type piezoelectric vibrator. FIG. 6 shows the result of the impact test. The frequency change rate indicates how much the oscillation frequency after the impact test is deviated with reference to the oscillation frequency of the tuning fork type piezoelectric vibrator before the impact test. FIG. 6A shows a test result of the tuning fork type piezoelectric vibrator 70 described above, and FIG. 6B shows a result of an impact test of the tuning fork type piezoelectric vibrator according to the prior art. It can be seen from FIG. 6A that the tuning fork type piezoelectric vibrator 70 described above has almost no deviation in the oscillation frequency even after the impact test. When the variation in the oscillation frequency after the impact test is obtained, σ = 0.221. It was. On the other hand, the tuning fork type piezoelectric vibrator according to the prior art shows that the oscillation frequency greatly deviates after the impact test as shown in FIG. 6B, and when the variation of the oscillation frequency after the impact test is obtained, σ = 2. 061. From this, it can be said that the tuning fork type piezoelectric vibrator 70 described above relaxed the impact by the impact mitigating portion 72 of the tuning fork type piezoelectric vibrating piece 50, and thus it can be said that there was almost no deviation in the oscillation frequency. In addition, since the tuning fork type piezoelectric vibrator according to the related art does not include the impact relaxation part, it can be said that the base part and the vibrating arm are subjected to an impact, and the oscillation frequency is greatly shifted.

  The tuning fork type piezoelectric vibrator 70 according to the second related embodiment includes the mount for electrically and mechanically connecting the tuning fork type piezoelectric vibrating piece 50 and the package side mount electrode 62, and the tuning fork type piezoelectric vibrating piece 50. However, the tuning fork-type piezoelectric vibrating piece 50 may be mounted on the package base 60 only by the mount portion. FIG. 7 shows an explanatory view of a modification of the tuning fork type piezoelectric vibrator according to the second embodiment. FIG. 7A is a plan view of the tuning fork type piezoelectric vibrator, and FIG. 7B is a cross-sectional view of the tuning fork type piezoelectric vibrator. In FIG. 7A, the lid is omitted. In the long side portion 58, the mount portion 74 is provided on the distal end side of the vibrating arm 54 from the position of the center of gravity of the tuning fork type piezoelectric vibrating piece 50. The mount portion 74 is formed long along the long side portion 58 and is connected to the package base 60 in a line. That is, the bonding material 64 is provided in a portion surrounded by a dotted line in FIG. 7A, and the tuning fork type piezoelectric vibrating piece 50 is mounted on the package base 60. Thus, even if the tuning fork type piezoelectric vibrating piece 50 is supported at two locations, the tuning fork type piezoelectric vibrating piece 50 is mounted in parallel to the bottom surface of the package base 60. Therefore, even if an impact is applied to the tuning fork type piezoelectric vibrator 70, the tuning fork type piezoelectric vibrating piece 50 does not collide with the package base 60.

  Next, a modification of the tuning fork type piezoelectric vibrating piece according to the second related embodiment will be described. FIG. 3 is an explanatory view of a modification of the tuning fork type piezoelectric vibrating piece. 3 (a) and 3 (b) are views showing a first modification, FIG. 3 (a) is a plan view, and FIG. 3 (b) is a side view. The first modified example has the same outer shape as the tuning-fork type piezoelectric vibrating piece 50 according to the second embodiment, but the connection electrode 82 (mount part 85) of the long side part 80 to the short side part 81 are thinly formed. It is a thing. Half etching or the like may be used for thinning the long side portion 80. FIG. 3C is a diagram showing a second modification. In the second modified example, a portion between the mount portion 85 provided on the long side portion 80 and the short side portion 81 is formed thin, and the long side portion 80 between the mount portion 85 and the support portion 84 is thickened inward. Formed. FIG. 3D is a diagram showing a third modification. In the third modified example, the long side portion 80 is formed thin, and only the mount portion 85 provided with the connection electrode is formed thick. FIG. 3E is a diagram showing a fourth modification. In the fourth modified example, a portion between the mount portion 85 provided on the long side portion 80 and the short side portion 81 is formed thin, and a portion between the mount portion 85 and the support portion 84 is formed thick outside. . FIG. 3F is a diagram showing a fifth modification. In the fifth modified example, a portion between the mount portion 85 provided on the long side portion 80 and the short side portion 81 is formed thin, and a portion between the mount portion 85 and the support portion 84 is formed thick on the inside and outside. It is. FIG. 3G shows a sixth modification. In the sixth modified example, the long side portion 80 is formed thin, the mount portion 85 provided with the connection electrode is formed thick on the inside, and between the vicinity of the connection portion between the base portion and the vibrating arm to the support portion 84 on the outside. It is thick. The mount portions 85 of the first to sixth modifications are provided on the tip side of the vibrating arm with respect to the center of gravity of the tuning fork type piezoelectric vibrating piece. The mount portion 85 is formed longer than the place where the bonding material is provided, that is, the connection electrode. Therefore, when the impact relaxation portion vibrates due to impact, the stress of the vibration is concentrated on the long side portion 80 located on the end portion of the bonding material, but the width of the long side portion 80 where the stress is applied is formed thick. Therefore, the long side part 80 does not break. Such first to sixth modifications can exhibit the same operations and effects as the tuning fork type piezoelectric vibrating piece 50 according to the second embodiment.

  Next, an embodiment of the present invention will be described. FIG. 8 is an explanatory diagram of a tuning fork type piezoelectric vibrating piece according to an embodiment of the present invention. The tuning fork type piezoelectric vibrating piece according to the embodiment of the present invention is a form in which the base is not provided on the tuning fork type piezoelectric vibrating piece main body. 8A is a plan view of a tuning fork type piezoelectric vibrating piece having a frame portion, and FIG. 8B is a plan view of a tuning fork type piezoelectric vibrating piece having no frame portion. A tuning fork-type piezoelectric vibrating piece 200 shown in FIG. 8A has a rectangular frame portion 202, and a vibrating arm 208 extending toward the other short side portion 206 inside one short side portion 204 of the frame portion 202. Is provided. The other short side portion 206 is formed to have a wide width, and a mounting portion 209 for mounting the tuning fork type piezoelectric vibrating piece 200 on a package base (not shown) is formed on the lower surface thereof. The long side portion 210 of the frame portion 202 is an impact relaxation portion, and the thickness and width of the long side portion 210 are adjusted in accordance with the size and position of the center of gravity of the vibrating arm. It has a function (impact mitigation part) to relieve this impact when an impact is applied. Further, the impact relaxation function may be provided in a part of the long side portion. In this case, the length, width, and thickness of the impact relaxation function are adjusted. Furthermore, the long side part 210 may be formed in the shape of the long side part 80 described in the modification of the second related embodiment. An excitation electrode (not shown) is formed on the vibrating arm 208 of the tuning fork type piezoelectric vibrating piece 200, and a connection electrode connected to a package side mount electrode (not shown) formed on the package base is formed on the mount portion 209. (Not shown) is formed. The excitation electrode and the mount electrode are connected via an extraction electrode (not shown) provided on the long side portion 210. Then, a bonding material is provided in a portion surrounded by a dotted line shown in FIG. 8A, the connection electrode and the mount electrode are conducted, and the tuning fork type piezoelectric vibrating piece 200 is mounted on the package base. As the bonding material, the bonding material 30 described in the first embodiment may be used. In this way, a tuning fork type piezoelectric vibrator is formed.

  A tuning fork type piezoelectric vibrating piece 220 shown in FIG. 8B has two vibrating arms 222 arranged in parallel, and one ends of these vibrating arms 222 are connected by a short side 224. A long side portion 226 is provided between the vibrating arms 222 along the vibrating arms 222. The tip of the long side portion 226 is extended in a direction intersecting with the direction along the vibrating arm 222 to form a short side portion 228. A foot portion is formed from the long side portion 226 and the short side portion 228, and the foot portion has a T shape. The lower surface of the short side portion 228 becomes a mount portion 230. The long side portion 226 is an impact relaxation portion, and the thickness and width are adjusted in accordance with the size of the vibrating arm 222, the position of the center of gravity, and the like. The long side portion 226 may be designed to have a thickness and a width in consideration of the size and the position of the center of gravity of the vibrating arm 222 in order to prevent the vibrating arm 222 from being twisted when an impact is applied. An excitation electrode (not shown) is formed on the vibrating arm 222 of the tuning-fork type piezoelectric vibrating piece 220, and the mount 230 is connected to a package side mount electrode (not shown) formed on a package base (not shown). A connection electrode (not shown) is formed. The excitation electrode and the mount electrode are connected via an extraction electrode (not shown) provided on the long side portion 226. Then, a bonding material is provided in a portion surrounded by a dotted line shown in FIG. 8B, the connection electrode and the mount electrode are conducted, and the tuning fork type piezoelectric vibrating piece 220 is mounted on the package base. As the bonding material, the bonding material 30 described in the first embodiment may be used. In this way, a tuning fork type piezoelectric vibrator is formed.

  When an impact due to dropping or the like is applied to the tuning-fork type piezoelectric vibrator mounting the tuning-fork type piezoelectric vibrating piece 200, 220 shown in FIG. 8A or FIG. 8B, the tuning-fork type piezoelectric vibrating piece 200, 220 is mounted. Although the impact is transmitted from the package base via the portions 209 and 230, the impact is mitigated by the long side portions 210 and 226 whose thickness and width are adjusted, and the vibrating arms 208 and 222 are not vigorously shaken. As a result, the tuning fork type piezoelectric vibrating reeds 200 and 220 can alleviate the impact, and the vibrating arms 208 and 222 are not damaged such as cracks or chips. The vibration arms 208 and 222 and the long side portions 210 and 226 have a distance larger than the amplitude at which the vibration arms 208 and 222 vibrate when an impact is applied to the tuning-fork type piezoelectric vibration pieces 200 and 220. Therefore, the vibrating arms 208 and 222 do not collide with the long side portions 210 and 226 to cause breakage, chipping, or the like. Further, since the tuning fork type piezoelectric vibrating reeds 200 and 220 do not have a base portion, the size can be reduced.

In addition, since the long side portions 210 and 226 are provided between the vibrating arms 208 and 222 and the mount portions 209 and 230, the vibration leaking from the vibrating arms 208 and 222 can be attenuated in the long side portions 210 and 226. it can. Therefore, a tuning fork type piezoelectric vibrator having excellent vibration characteristics can be obtained.
When a circuit for oscillating the tuning fork type piezoelectric vibrating pieces 200 and 220 is mounted on the tuning fork type piezoelectric vibrator described above, a tuning fork type piezoelectric oscillator can be obtained.

  Next, a third related embodiment will be described. FIG. 9 is an explanatory view of a tuning fork type piezoelectric vibrating piece and a tuning fork type piezoelectric vibrator according to a third related embodiment. A tuning fork type piezoelectric vibrating piece 240 according to the third related embodiment has a tuning fork type piezoelectric vibrating piece main body 246 including a base 242 and a plurality of vibrating arms 244 extending from one end of the base 242. This is a configuration in which a rectangular frame portion 248 is provided around the piezoelectric piezoelectric vibrating piece body 246. One short side 250 of the frame 248 is connected to the other end of the base 242. Further, the long side portion 252 of the frame portion 248 is provided with a shock absorbing portion 254 and a mount portion 256 on the distal end side of the vibrating arm 244 with respect to the center of gravity of the tuning fork type piezoelectric vibrating piece 240.

  The impact relaxation portion 254 is formed from the mount portion 256 to one short side portion 250, and is formed by making this portion thinner and thinner as shown in FIG. Further, as shown in FIG. 9B, the impact relaxation portion 254 is formed thin and thin in a part of the long side portion 252, that is, in a portion from the mount portion 256 to one short side portion 250 in the long side portion 252. A portion may be provided. The thin and thin portion, that is, the constricted portion may be provided in the vicinity of the central portion between the mount portion 256 and one short side portion 250. A plurality of constricted portions may be formed on the long side portion 252. Further, the thickness, thickness, and length of the thin and thin portion are designed according to the size of the tuning fork type piezoelectric vibrating piece 240, the position of the center of gravity, and the like.

  A connection electrode (not shown) is provided on the lower surface of the mount portion 256, and the connection electrode may be formed in a dot shape or may be formed in a line shape along the long side portion 252. When the tuning fork type piezoelectric vibrating piece 240 shown in FIG. 9A or 9B is mounted on the package base 258, the mount portion 256 and the package base 258 are bonded via the bonding material 260. As the bonding material 260, the bonding material 30 described in the first embodiment may be used. FIG. 9C is a cross-sectional view of a tuning fork type piezoelectric vibrator. FIG. 9C shows a form in which the tuning fork type piezoelectric vibrating piece 240 shown in FIG. The bonding material 260 is provided closer to the distal end side of the vibrating arm 244 than the connection portion between the mount portion 256 and the thin and thin portion. That is, the tuning fork type piezoelectric vibrating piece 240 and the package base 258 are joined at a position away from the connection location. By the way, when the end portion of the bonding material 260 is positioned on the lower surface of the connection portion, when the impact is applied to the tuning fork type piezoelectric vibrating piece 240 and the impact relaxation portion 254 is shaken, stress due to the vibration is concentrated on the connection portion. To do. And since the intensity | strength of the part which formed the long side part 252 thinly and thinly is weak, the said connection location will be broken by the said stress. However, in the present embodiment, since the mount portion 256 is located above the end portion of the bonding material 260, it does not break even if stress is concentrated due to the vibration of the impact relaxation portion 254. Since the tuning fork type piezoelectric vibrating piece 240 is linearly bonded to the package base 258 at each mount portion 256, the tuning fork type piezoelectric vibrating piece 240 can be mounted in parallel to the bottom surface of the package base 258. Further, when the connection electrode is provided in a dot shape, the lower surface of the short side portion 262 on the distal end side of the vibrating arm 244 may be used as a support portion. As a result, the tuning fork type piezoelectric vibrating piece 240 is joined to the package base 258 at each mount portion 256 and the support portion, and the tuning fork type piezoelectric vibrating piece 240 can be mounted in parallel to the bottom surface of the package base 258.

  Moreover, the impact relaxation part 254 may be formed by providing the hole part 264 in the long side part 252 as shown in FIG.9 (d). As the shape of the hole portion 264, any shape may be used according to the design of the impact relaxation portion 254. For example, a circle, an ellipse, a rectangle, a triangle, or the like can be used. Further, the size and the arrangement interval of the hole portions 264 can be arbitrarily set according to the design of the impact relaxation portion 254. The hole may be formed at the same time as the tuning fork type piezoelectric vibrating piece 240 is formed by etching. A concave portion can be used instead of the hole portion 264. The recess may be formed at the same time as the groove provided in the vibrating arm 244. And the depth of the said recessed part can be arbitrarily adjusted by stopping etching only the said recessed part in the middle of forming the said groove | channel by etching. The concave portion may be formed only on either the upper surface or the lower surface of the long side portion 252 or may be formed on both surfaces.

  When an impact due to dropping or the like is applied to the tuning fork type piezoelectric vibrator mounting the tuning fork type piezoelectric vibrating piece 240 described above, the impact is transmitted from the package to the tuning fork type piezoelectric vibrating piece 240 through the mount portion 256. When the portion 252 vibrates, the impact is alleviated and the tuning fork type piezoelectric vibrating reed main body 246 is not vigorously shaken. As a result, the tuning fork type piezoelectric vibrating piece 240 can alleviate the impact, and the vibrating arm 244 is not damaged such as cracking or chipping. Further, since the vibration arm 244 and the long side portion 252 have a distance larger than the amplitude at which the vibration arm 244 vibrates when an impact is applied to the tuning fork type piezoelectric vibrating piece 240, the vibration arm 244 is long. It does not collide with the side 252 and damage such as cracks or chipping occurs.

Further, since the long side portion 252 is provided between the vibrating arm 244 and the mount portion 256, vibration leaking from the vibrating arm 244 can be attenuated at the long side portion 252. Therefore, a tuning fork type piezoelectric vibrator having excellent vibration characteristics can be obtained.
When a circuit for oscillating the tuning fork type piezoelectric vibrating piece 240 is mounted on the tuning fork type piezoelectric vibrator described above, a tuning fork type piezoelectric oscillator can be obtained.

  Next, the groove will be described. Since the groove is provided in the vibrating arm, it can be provided in the vibrating arms of all tuning fork type piezoelectric vibrating pieces regardless of the shape of the tuning fork type piezoelectric vibrating piece. Therefore, the groove can be formed in the tuning fork type piezoelectric vibrating piece according to the first to fourth embodiments. FIG. 10 is an explanatory diagram of grooves provided in the vibrating arm. 10A is a plan view of the tuning-fork type piezoelectric vibrating piece main body, and FIG. 10B is a cross-sectional view taken along the line AA. In FIG. 10, the excitation electrode and the like are omitted. The grooves 266 are formed on the upper and lower surfaces of the vibrating arm 268 along the longitudinal direction of the vibrating arm 268. Therefore, the cross-sectional shape of the vibrating arm 268 is H-shaped. Providing the groove 266 in the vibrating arm 268 improves the electric field efficiency of the vibrating arm 268 due to the voltage applied to the excitation electrode, and even if the vibrating arm 268 is shortened and / or thinned to reduce the size, the vibration loss of flexural vibration Is low and the crystal impedance value can be kept low.

  In the above-described embodiments, the impact mitigating portions have been described. However, instead of these impact mitigating portions, an impact mitigating portion having a form described below can be used. FIG. 11 is an explanatory diagram of the impact relaxation portion. Note that, as an example of a tuning fork type piezoelectric vibrating piece to which the impact relaxation unit 270 is applied, a tuning fork type piezoelectric vibrating piece 272 having a tuning fork type piezoelectric vibrating piece main body 274 and a rectangular frame portion 276 surrounding the main body is provided. The form used is described. The impact relaxation portion 270 is provided between the mount portion 280 in the long side portion 278 of the frame portion 276 and the short side portion 282 on the base side. Then, along the length direction of the long side portion 278, it is formed by making cuts alternately from the inside and outside of the long side portion 278. That is, the impact relaxation part 270 is formed in a spring shape. The length of the impact relaxation portion 270 and the width and length of the cut are appropriately designed according to the size of the tuning fork type piezoelectric vibrating piece 272, the position of the center of gravity, and the like. Such an impact relaxation part 270 may be formed at the same time as the tuning fork type piezoelectric vibrating piece 272 is formed by etching. When such a tuning fork type piezoelectric vibrating piece 272 is mounted on a package (not shown), a tuning fork type piezoelectric vibrator is formed. When an impact is applied to the tuning fork type piezoelectric vibrator, the impact is transmitted to the tuning fork type piezoelectric vibrating piece 272. However, the impact relaxation unit 270 is shaken to reduce the impact. Further, since the distance from the tuning fork type piezoelectric vibrating piece main body 274 to the mount portion 280 is increased, the vibration leakage of the bending vibration can be attenuated, and a tuning fork type piezoelectric vibrator having excellent vibration characteristics can be obtained.

10 ......... Tuning Fork Type Piezoelectric Vibrating Piece, 12 ......... Base, 14 ......... Vibrating Arm, 16 ......... Tuning Fork Type Piezoelectric Vibrating Body, 18 ......... Short Side, 20 ......... Long Side, 22 ......... Shock mitigating portion, 26 ......... Mounting portion, 50 ......... Tuning fork type piezoelectric vibrating piece, 52 ......... Base, 54 ......... Vibrating arm, 56 ......... Tuning fork type piezoelectric vibrating piece main body, 58 ......... long side, 72 ......... impact mitigating part.

Claims (5)

A piezoelectric vibrator in which a tuning fork type piezoelectric vibrating piece is housed in a package,
The tuning fork type piezoelectric vibrating piece is
A tuning-fork type piezoelectric vibrating piece main body having a plurality of vibrating arms;
A first short side portion formed along a direction intersecting with the extending direction of the vibrating arm and connected to the piezoelectric vibrating piece main body;
A long side portion formed along the extending direction of the vibrating arm from the first short side portion toward the extending direction of the vibrating arm to the tip of the vibrating arm;
A second short side portion formed by extending a tip of the long side portion along a direction intersecting with a direction in which the vibrating arm extends before the tip of the vibrating arm;
With
The piezoelectric vibrator having a lower surface of the second short side portion fixed to the package. The piezoelectric vibrator according to claim 1,
The plurality of vibrating arms includes a pair of vibrating arms,
The long side portion is formed between the pair of vibrating arms from the first short side portion to the tip of the vibrating arm in a direction in which the vibrating arm extends. Piezoelectric vibrator. The piezoelectric vibrator according to claim 1,
The plurality of vibrating arms includes a pair of vibrating arms,
The long side portion is formed on the outer side of the pair of vibrating arms from the first short side portion to the tip of the vibrating arm toward the extending direction of the vibrating arm. Part and a second long side part,
The first long side portion and the second long side portion are connected to each other by the second short side portion on the distal end side of the vibrating arm. The piezoelectric vibrator according to any one of claims 1 to 3,
The piezoelectric vibrator according to claim 1, wherein the long side portion is an impact relaxation portion formed by providing a hole portion or a concave portion. The piezoelectric vibrator according to any one of claims 1 to 4,
The piezoelectric vibrator according to claim 1, wherein an interval between the vibrating arm and the long side portion is wider than an amplitude at which the vibrating arm vibrates when an impact is applied to the piezoelectric vibrator.

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