JP2013012965A - Piezoelectric vibration piece and piezoelectric device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a piezoelectric vibration piece and a piezoelectric device which are configured to reduce the influence of stress on an exciting part.SOLUTION: A piezoelectric vibration piece (130) comprises: an exciting part (131) having a first side (138a) and a second side (138b); a frame part (132) that surrounds the exciting part; and a connection part (133) which connects the first side of the exciting part and the frame part, and has a length in a first direction that is a second length. The exciting part has on both main surfaces thereof a first region (131a) for forming an excitation electrode (134) and a second region (131b). The second region (131b) includes a slit (137) extending through both the main surfaces of the exciting part and extending in the first direction, and the first side, and is formed with being surrounded by an end of the slit closer to the first region and the first side. The slit is formed at a position shifted from the first side in a second direction of the connection part by a dimension of a third length. The second length is smaller than the first length. The length of the slit in the first direction is not less than the second length nor more than the first length.

Description

  The present invention relates to a piezoelectric vibrating piece or a piezoelectric device in which the influence of stress on an excitation unit is suppressed.

  A piezoelectric vibrating piece having an excitation unit that vibrates at a predetermined frequency is known. For example, the piezoelectric vibrating piece is fixedly held in a package by a holding member or the like to form a piezoelectric device, and is used by being mounted on a printed board or the like. In such a piezoelectric vibrating piece, there is a problem that the vibration characteristics change due to stress such as strain generated at the time of packaging.

  To deal with such a problem, for example, Patent Document 1 discloses a piezoelectric vibrator piece that is formed as a slit through an outer periphery of a vibration part that generates main vibration. In the piezoelectric vibrator piece disclosed in Patent Document 1, the portion held by the holding member and the vibration portion are mechanically separated, so that distortion generated during packaging is not easily transmitted to the vibration portion. .

JP-A-5-226963

  However, even in Patent Document 1, it is not sufficient to suppress the change in the vibration characteristics of the piezoelectric vibrating piece. In addition to the strain generated during packaging, bending stress applied to the printed circuit board is transmitted to the piezoelectric vibrating piece, so that stress is always applied to the piezoelectric vibrating piece even when the piezoelectric device is mounted on the printed circuit board. Exposed to the possibility of receiving. Therefore, in the piezoelectric vibrating piece, it is desired that stress is not further applied to the excitation unit, and the change in vibration characteristics is suppressed.

  An object of the present invention is to provide a piezoelectric vibrating piece and a piezoelectric device in which the influence of stress on the excitation unit is suppressed by forming a slit in the excitation unit.

  A piezoelectric vibrating piece according to a first aspect is a rectangular shape having a first side extending in a first direction and a pair of second sides extending in a second direction orthogonal to the first direction. An excitation unit, a frame surrounding the excitation unit, a first side of the excitation unit and the frame unit, and a connection unit having a second length in the first direction. The excitation unit includes a rectangular first region in which excitation electrodes are formed on both main surfaces, a slit and a first side extending through both main surfaces of the excitation unit in a first direction, and the first region side of the slit A rectangular second region formed by being sandwiched between the first end and the first side. The slit is formed at a position moved by a third length from the first side in the second direction of the connecting portion, the second length is smaller than the first length, and the length of the slit in the first direction is the second length. It is not less than the first length.

  In the piezoelectric vibrating piece according to the second aspect, the second side is longer than the first side in the first aspect.

  In the piezoelectric vibrating piece according to the third aspect, in the first aspect or the second aspect, the connecting portion is connected to one end of the first side, and the slit is connected to the end of the first side to which the connecting portion is connected. It is formed through the second side.

  In the piezoelectric vibrating piece according to the fourth aspect, in the first aspect or the second aspect, the connecting portions are respectively connected to both ends of the first side. Each slit extending in the second direction of each connecting portion is formed so as to penetrate through each second side connected to the end of the first side to which each connecting portion is connected, and each slit is separated from each other.

  In the piezoelectric vibrating piece according to the fifth aspect, in the first aspect or the second aspect, the connecting portion is connected to the center of the first side, and the slit does not penetrate through the pair of second sides.

  In the piezoelectric vibrating piece according to the sixth aspect, the third length is smaller than the second length in the first to fifth aspects.

  A piezoelectric device according to a seventh aspect includes a piezoelectric vibrating piece according to the first to sixth aspects, a lid joined to one main surface of the frame portion of the piezoelectric vibrating piece, and the other main surface of the frame portion of the piezoelectric vibrating piece. And a base bonded to.

  According to the piezoelectric vibrating piece of the present invention, the effect of stress on the excitation unit can be suppressed by forming the slit in the excitation unit.

1 is an exploded perspective view of a piezoelectric device 100. FIG. 1 is a cross-sectional view of a piezoelectric device 100. FIG. FIG. 4A is a plan view of the piezoelectric vibrating piece 130. FIG. FIG. 4B is a cross-sectional view of the piezoelectric vibrating piece 130. (A) is a top view of the piezoelectric vibrating piece 130 in which no electrode is formed. FIG. 4B is an enlarged view of a region 161 surrounded by a dotted line in FIG. (A) is a top view of the piezoelectric vibrating piece 230b. FIG. 6B is a cross-sectional view of the piezoelectric vibrating piece 230b. (A) is a schematic sectional drawing of the printed circuit board 200 and the piezoelectric device 100 mounted in the printed circuit board 200. FIG. (B) is a schematic plan view of the piezoelectric vibrating piece 230a. (C) is a schematic plan view of the piezoelectric vibrating piece 230b. It is a graph in which the maximum stress value concerning the mesa part 231 was shown. It is the result of the simulation of the stress concerning a piezoelectric vibrating piece. (A) is a schematic plan view of the piezoelectric vibrating piece 230d. (B) is a schematic plan view of the piezoelectric vibrating piece 230e. FIG. 4A is a plan view of the piezoelectric vibrating piece 330. FIG. 5B is a plan view of the piezoelectric vibrating piece 330 on which no electrode is formed. FIG. 6A is a plan view of the piezoelectric vibrating piece 430. FIG. FIG. 4B is a plan view of the piezoelectric vibrating piece 430 on which no electrode is formed.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, preferred embodiments of the invention will be described in detail with reference to the drawings. It should be noted that the scope of the present invention is not limited to these forms unless otherwise specified in the following description.

(First embodiment)
<Configuration of Piezoelectric Device 100>
FIG. 1 is an exploded perspective view of the piezoelectric device 100. The piezoelectric device 100 includes a lid 110, a base 120, and a piezoelectric vibrating piece 130. As the piezoelectric vibrating piece 130, for example, an AT-cut crystal vibrating piece is used. The AT-cut quartz crystal resonator element has a principal surface (YZ plane) inclined with respect to the Y axis of the crystal axis (XYZ) by 35 degrees 15 minutes from the Z axis in the Y axis direction around the X axis. In the following description, the new axes tilted with respect to the axial direction of the AT-cut quartz crystal vibrating piece are used as the Y ′ axis and the Z ′ axis. That is, in the piezoelectric device 100, the long side direction of the piezoelectric device 100 is described as the X-axis direction, the height direction of the piezoelectric device 100 is defined as the Y′-axis direction, and the direction perpendicular to the X and Y′-axis directions is described as the Z′-axis direction. .

  The piezoelectric vibrating piece 130 includes an excitation part 131 that vibrates at a predetermined frequency, a frame part 132 that surrounds the excitation part 131, and a connection part 133 that connects the excitation part 131 and the frame part 132. A region other than the coupling portion 133 between the excitation portion 131 and the frame portion 132 is a through hole 136 that penetrates the piezoelectric vibrating piece 130 in the Y′-axis direction. Excitation electrodes 134 are formed on the surface on the + Y′-axis side and the surface on the −Y′-axis side of the excitation unit 131, and the extraction electrode 135 extends from each excitation electrode 134 to the frame portion 132 through the coupling portion 133. Has been pulled out. The excitation unit 131 is formed with a slit 137 that extends through the excitation unit 131 in the Y′-axis direction and extends in the Z′-axis direction.

  The base 120 is disposed on the −Y′-axis side of the piezoelectric vibrating piece 130. The base 120 is formed in a rectangular shape having a long side in the X-axis direction and a short side in the Z′-axis direction. A pair of mounting terminals 124 is formed on the surface of the base 120 on the −Y′-axis side. The mounting terminal 124 is fixed and electrically connected to a printed circuit board or the like via solder, whereby the piezoelectric device 100 is mounted on the printed circuit board or the like. Further, castellations 126 are formed on the side surfaces of the four corners of the base 120, and side electrodes 125 are formed on the castellations 126. A recess 121 is formed on the surface of the base 120 on the + Y′-axis side, and a bonding surface 122 is formed around the recess 121. In addition, connection electrodes 123 are formed around the castellations 126 at the four corners of the joint surface 122. The connection electrode 123 is electrically connected to the mounting terminal 124 via a side electrode 125 formed on the castellation 126. The base 120 is bonded to the surface at the −Y′-axis side of the frame portion 132 of the piezoelectric vibrating piece 130 via the sealing material 141 (see FIG. 2) at the bonding surface 122. Further, the connection electrode 123 and the extraction electrode 135 of the piezoelectric vibrating piece 130 are electrically connected.

  The lid 110 is disposed on the + Y′-axis side of the piezoelectric vibrating piece 130. A recess 111 is formed on the surface of the lid 110 on the −Y′-axis side, and a bonding surface 112 is formed around the recess 111. The lid 110 is bonded to the surface on the + Y′-axis side of the frame portion 132 of the piezoelectric vibrating piece 130 via the sealing material 141 (see FIG. 2) at the bonding surface 112.

  FIG. 2 is a cross-sectional view of the piezoelectric device 100. 2 is a cross-sectional view taken along the line AA of FIG. In the piezoelectric device 100, the bonding surface 112 of the lid 110 is bonded to the surface on the + Y′-axis side of the frame portion 132 of the piezoelectric vibrating piece 130 via the sealing material 141, and the surface on the −Y′-axis side of the frame portion 132. The joining surface 122 of the base 120 is joined via the sealing material 141. When the frame portion 132 of the piezoelectric vibrating piece 130 and the bonding surface 122 of the base 120 are bonded, the bonding surface 122 of the extraction electrode 135 and the base 120 formed on the surface at the −Y′-axis side of the frame portion 132. Are electrically connected to the connection electrode 123. Thus, the excitation electrode 134 is electrically connected to the mounting terminal 124 via the extraction electrode 135, the connection electrode 123, and the side electrode 125.

  FIG. 3A is a plan view of the piezoelectric vibrating piece 130. The piezoelectric vibrating piece 130 includes an excitation part 131, a frame part 132 that surrounds the excitation part 131, and a connecting part 133 that connects the excitation part 131 and the frame part 132. The connecting portion 133 is connected to the + Z′-axis side of the first side 138 a that is the −X-axis side side of the excitation unit 131, and extends in the −X-axis direction therefrom to be connected to the frame portion 132. Further, a region other than the coupling portion 133 between the excitation portion 131 and the frame portion 132 is a through hole 136 that penetrates the piezoelectric vibrating piece 130 in the Y′-axis direction.

  The excitation unit 131 is formed in a rectangular shape including a first side 138a and a second side 138b that is a side of the excitation unit 131 on the + Z′-axis side and the −Z′-axis side. The excitation unit 131 can be divided into two regions, a first region 131a and a second region 131b. The first region 131 a is a rectangular region on the + X-axis side of the excitation unit 131, and is a region where the excitation electrode 134 is formed on the surface on the + Y′-axis side and the −Y′-axis side. The second region 131b is a region formed in a rectangular shape on the −X axis side of the first region 131a. The second region 131b includes a first side 138a and a slit 137 connected to the connecting portion 133, and the first side 138a and the end of the slit 137 on the first region 131a side (the end on the + X axis side of the slit 137). And a straight line 139 parallel to the Z ′ axis. The slit 137 formed in the second region 131b is formed in the + X-axis direction of the connecting portion 133 and penetrates the second side 138b on the + Z′-axis side of the excitation portion 131 and is connected to the through hole 136.

  In the piezoelectric vibrating piece 130, the extraction electrode 135 extracted from the excitation electrode 134 formed on the surface on the + Y′-axis side is extracted to the −X-axis side frame portion 132 through the second region 131 b and the connection portion 133. Further, the side surface 135a including the corner portion on the + Z-axis side of the + X-axis side of the frame portion 132 that extends in the + X-axis direction through the + Z′-axis side of the frame portion 132 and faces the through hole 136 (FIGS. 1 and 2) Through the + Y′-axis side to the surface on the −Y′-axis side through the + Y′-axis side to the corner on the + Z-axis side of the −Y′-axis side surface of the frame portion 132. . In addition, the extraction electrode 135 extracted from the excitation electrode 134 formed on the surface at the −Y′-axis side is extracted to the −X-axis side frame portion 132 through the second region 131b and the connecting portion 133, and − It extends in the Z′-axis direction and is formed up to the −Z′-axis side corner of the −X′-axis side surface of the frame 132 on the −Y′-axis side.

  FIG. 3B is a cross-sectional view of the piezoelectric vibrating piece 130. FIG.3 (b) is sectional drawing of the BB cross section of Fig.3 (a). FIG. 3B shows the relationship between the first region 131a, the second region 131b, and the connecting portion 133. The first region 131a and the second region 131b are adjacent to each other in the X-axis direction. The first region 131a is sandwiched between the through hole 136 and the second region 131b in the X-axis direction, and excitation electrodes 134 are formed on the surfaces of the first region 131a on the + Y′-axis side and the −Y′-axis side. Yes. The second region 131b is formed between the first region 131a and the connecting portion 133 in the X-axis direction. A slit 137 is formed on the + X axis side of the second region 131b, and a first side 138a is provided on the −X axis side of the second region 131b. In the piezoelectric vibrating piece 130, the excitation unit 131, the coupling unit 133, and the frame unit 132 are formed with the same thickness in the Y′-axis direction, and the thickness is defined as thickness WY <b> 1.

  FIG. 4A is a plan view of the piezoelectric vibrating piece 130 on which no electrode is formed. The length of the first side 138a of the excitation unit 131 is the first length L1, and the second side 138b is formed to the length LX2. In the piezoelectric vibrating piece 130, since the first side 138a is the short side of the excitation unit 131 and the second side 138b is the long side of the excitation unit 131, the first length L1 is shorter than the length LX2. Further, the entire length of the frame portion 132 of the piezoelectric vibrating piece 130 is the length WX1, the entire length of the Z′-axis direction is the length WZ1, and the X-axis of the frame portion 132 extends in the Z′-axis direction. The length in the direction is defined as length WX2, and the length in the Z′-axis direction of the frame portion 132 extending in the X-axis direction is defined as length WZ2. In the piezoelectric vibrating piece 130, for example, the first length L1 is 1.0 mm, the length LX2 is 1.4 mm, the length WX1 is 2.0 mm, the length WX2 is 0.2 mm, and the length is, for example, WZ1 is 1.6 mm and length WZ2 is 0.2 mm.

  FIG. 4B is an enlarged view of a region 161 surrounded by a dotted line in FIG. The length in the Z′-axis direction of the connecting portion 133 of the piezoelectric vibrating piece 130 is the second length L2, and the length in the X-axis direction between the slit 137 and the first side 138a is formed to the third length L3. Has been. The length of the slit 137 in the X-axis direction is the length SX1, the length of the Z′-axis direction is the length SZ1, and the width of the through-hole 136 in the X-axis direction and the Z′-axis direction is the width MX1 and the width MZ1. . In the piezoelectric vibrating piece 130, for example, the second length L2 is 0.5 mm, the third length L3 is 0.18 mm, the length SX1 is 0.07 mm, the length SZ1 is 0.5 mm, the length MZ1 and the length. Both MX1 are formed to 0.1 mm. In the piezoelectric vibrating piece 130, in order to make the excitation electrode 134 as large as possible, the area of the first region 131a is widened and the area of the second region 131b is narrowed. That is, the third length L3 is formed short. In addition, since strong stress is applied to the connecting portion 133 as shown in FIG. 8 to be described later, the second length L2 of the connecting portion 133 is formed long in order to improve the impact resistance of the piezoelectric vibrating piece. Is desirable. Therefore, in the piezoelectric vibrating piece 130, the second length L2 is formed longer than the third length L3.

<Simulation>
When bending stress is applied to the printed circuit board on which the piezoelectric device is mounted, stress is also applied to the piezoelectric device and the piezoelectric vibrating piece. The portion of the piezoelectric vibrating piece to which these stresses are applied and the size thereof can be calculated by simulation, and it has been confirmed that the value of this simulation is close to the value of the actually measured stress. Hereinafter, simulation results regarding the stress applied to the piezoelectric vibrating piece when a bending stress is applied to the printed circuit board on which the piezoelectric device is mounted will be described. In the following description, the same parts as those of the piezoelectric vibrating piece 130 are denoted by the same symbols as those of the piezoelectric vibrating piece 130, and the description thereof is omitted.

  FIG. 5A is a plan view of the piezoelectric vibrating piece 230b. The simulation was performed on the assumption that the piezoelectric vibrating piece 230b and the modified example thereof were used in the piezoelectric device 100 instead of the piezoelectric vibrating piece 130. The piezoelectric vibrating piece 230b is a mesa-type piezoelectric vibration in which the region where the excitation electrode 134 of the first region 131a of the piezoelectric vibrating piece 130 is formed is a mesa portion 231 that is thicker in the Y′-axis direction than the second region 131b. It is a piece. The other partial configurations are the same as those of the piezoelectric vibrating piece 130.

  FIG. 5B is a cross-sectional view of the piezoelectric vibrating piece 230b. FIG.5 (b) is sectional drawing of CC cross section of Fig.5 (a). The piezoelectric vibrating piece 230 has a mesa portion 231 formed in the first region 131a. The thickness of the mesa portion in the Y′-axis direction is formed to a thickness RY1, and the thickness RY1 is around the frame portion 132, the connecting portion 133, the second region 131b, and the mesa portion 231 of the first region 131a. Is thicker than WY1.

  FIG. 6A is a schematic cross-sectional view of the printed circuit board 200 and the piezoelectric device 100 mounted on the printed circuit board 200. The piezoelectric device 100 is mounted on the surface at the + Y′-axis side of the printed circuit board 200. In the simulation, it is assumed that a force 170 in the + Y′-axis direction is applied to the −Y′-axis side surface of the printed circuit board 200 and a bending stress is generated in the printed circuit board 200. Further, in the simulation, bending stress occurs when the printed circuit board 200 is bent in the X-axis direction (when the right direction is the + X-axis direction in FIG. 6A) and when bent in the Z′-axis direction (FIG. 6A). ) Is assumed that the right direction is the + Z′-axis direction).

  FIG. 6B is a schematic plan view of the piezoelectric vibrating piece 230a. In the second region 131b of the piezoelectric vibrating piece 230a, a slit 137a that penetrates through the second side 138b on the + Z′-axis side of the piezoelectric vibrating piece 230a and is connected to the through hole 136 is formed. The slit 137a is formed to have a length SZ2 in the Z′-axis direction, and the length SZ2 is half the second length L2 of the connecting portion 133 in the Z′-axis direction. Other components are the same as those of the piezoelectric vibrating piece 230b.

  FIG. 6C is a schematic plan view of the piezoelectric vibrating piece 230b. A slit 137 is formed in the second region 131b of the piezoelectric vibrating piece 230b. As described with reference to FIG. 4B, the slit 137 has a length in the Z′-axis direction that is the length SZ1, and is the same length as the second length L2 of the connecting portion 133 in the Z′-axis direction. Therefore, the −Z′-axis side end of the slit 137 and the −Z′-axis side end of the connecting portion 133 exist on the same straight line extending in the X-axis direction.

  FIG. 6D is a schematic plan view of the piezoelectric vibrating piece 230c. In the piezoelectric vibrating piece 230c, a slit 137c is formed in the second region 131b. Other components are the same as those of the piezoelectric vibrating piece 230b. The slit 137c is formed to have a length SZ3 in the Z′-axis direction, and the length SZ3 is 1.5 times the second length L2 of the connecting portion 133 in the Z′-axis direction.

  FIG. 7 is a graph showing the maximum stress value applied to the mesa portion 231. In the graph of FIG. 7, regarding the piezoelectric vibrating piece 230a, the piezoelectric vibrating piece 230b, and the piezoelectric vibrating piece 230c, when the printed circuit board 200 is bent in the X-axis direction and when the printed circuit board 200 is bent in the Z′-axis direction, respectively. The maximum stress value applied in the mesa portion 231 is shown. The maximum stress value is expressed as a positive value of the stress in the pulling direction and a negative value of the stress in the compressing direction. The vertical axis of the graph represents the maximum stress value (MPa) applied to the mesa portion 231, and the horizontal axis represents Z ′ of each piezoelectric vibrating piece of the piezoelectric vibrating piece 230 a, the piezoelectric vibrating piece 230 b, and the piezoelectric vibrating piece 230 c. The case where the printed circuit board 200 is bent in the axial direction and the X-axis direction is shown separately.

  The piezoelectric vibrating piece 230 a is shown to have a maximum stress of slightly less than −1.00 MPa applied to the mesa portion 231 when the printed circuit board is bent in the Z′-axis direction. Further, it is shown that a maximum stress of slightly less than 0.2 MPa is applied in the mesa portion 231 when bent in the X-axis direction. In the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c, it is shown that a maximum stress of approximately 0 MPa is applied to the mesa portion 231 in each case bent in the Z′-axis direction and the X-axis direction. That is, it can be seen that the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c are hardly stressed in the mesa portion 231.

  FIG. 8 shows the result of the simulation of the stress applied to the piezoelectric vibrating piece. FIG. 8 shows simulation results of the piezoelectric vibrating piece 230a, the piezoelectric vibrating piece 230b, and the piezoelectric vibrating piece 230c when the printed circuit board is bent in the Z′-axis direction and the X-axis direction. In the simulation result shown in FIG. 8, only the excitation part 131 and the connection part 133 of each piezoelectric vibrating piece are shown, and the stress is almost 0 MPa in the region where the color of the mesa part 231 is uniform. .

  In bending the printed circuit board in the Z′-axis direction, it can be confirmed that stress is applied mainly to the −X axis side of the slit and the connecting portion 133 of each piezoelectric vibrating piece. In the piezoelectric vibrating piece 230a, it can be confirmed that the stress applied to the vicinity of the connecting portion 133 and the slit 137a extends in the direction of the first region 131a. On the other hand, in the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c, the influence of the stress on the first region 131a is not seen. In the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c, the length of the stress generated on the −X axis side of the slit in the Z′-axis direction is close to the length of the connecting portion 133 in the Z′-axis direction. On the other hand, in the piezoelectric vibrating piece 230c, no stress is generated at the end of the slit 137c on the −Z′-axis side.

  In bending the printed circuit board in the X-axis direction, it can be confirmed that stress is applied mainly to the −X-axis side of the slit and the connecting portion 133 of each piezoelectric vibrating piece. In the piezoelectric vibrating piece 230a, generation of stress is observed on the −X axis side and the −Z ′ axis side of the slit 137a. Further, in the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c, stress is generated on the −X axis side of the slit in the same manner as the result of bending the piezoelectric vibrating piece in the X axis direction. The length is close to the length of the connecting portion 133 in the Z′-axis direction. In the connecting portion 133, a stress distribution similar to that of each piezoelectric vibrating piece is observed.

  7 and 8, it can be seen that in the piezoelectric vibrating piece 230a, the stress in the vicinity of the slit 137a and the connecting portion 133 extends to the first region 131a. On the other hand, in the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c, it can be seen that the stress in the vicinity of the slit and the connecting portion 133 does not extend to the first region 131a. The stress observed in the vicinity of the slit has a similar shape in the piezoelectric vibrating piece 230b and the piezoelectric vibrating piece 230c and corresponds to the length of the connecting portion 133 in the Z′-axis direction. This is considered to be related to the length of the portion 133 in the Z′-axis direction. That is, when the slit is formed on the + X-axis side of the connecting portion 133 and the length of the slit in the Z′-axis direction is longer than the second length of the connecting portion 133 in the Z′-axis direction, It can be seen that the stress generated in the portion 133 does not extend to the first region 131a, and the stress is less likely to be applied to the first region 131a.

(Second Embodiment)
The length of the connecting portion of the piezoelectric vibrating piece in the Z′-axis direction can be formed in various lengths. Hereinafter, the piezoelectric vibrating piece in which the length of the connecting portion in the Z′-axis direction is changed will be described with reference to FIGS. 9A and 9B. In the following description, the same components as those in the first embodiment are denoted by the same symbols, and the description thereof is omitted.

<Configuration of Piezoelectric Vibrating Piece 230d and Piezoelectric Vibrating Piece 230e>
FIG. 9A is a schematic plan view of the piezoelectric vibrating piece 230d. In FIG. 9A, the electrode formed on the piezoelectric vibrating piece 230d is omitted. The piezoelectric vibrating piece 230d is formed by an excitation unit 131, a frame unit 132, and a connection unit 233d. In the piezoelectric vibrating piece 230d, the second length L2 in the Z′-axis direction of the coupling portion 233d is formed to be longer than half the length of the first side 138a, and the Z′-axis direction of the slit 137d formed in the second region 131b. Is formed to have the same length as the length L2 of the connecting portion 233d in the Z′-axis direction. The other configuration of the piezoelectric vibrating piece 230d is the same as that of the piezoelectric vibrating piece 230b shown in FIG. As shown in FIG. 8, the stress applied to the piezoelectric vibrating piece is mainly applied to the −X axis side of the connecting portion and the slit. For this reason, in the piezoelectric vibrating piece 230d, the impact resistance of the connecting portion where stress is easily applied is improved by increasing the length of the connecting portion 233d in the Z′-axis direction.

  FIG. 9B is a schematic plan view of the piezoelectric vibrating piece 230e. In FIG. 9B, the electrode formed on the piezoelectric vibrating piece 230e is omitted. The piezoelectric vibrating piece 230e is formed by an excitation part 131, a frame part 132, and a connection part 233e. In the piezoelectric vibrating piece 230e, the second length L2 of the coupling portion 233e in the Z′-axis direction is formed to be shorter than half the length of the first side 138a, and the Z′-axis direction of the slit 137e formed in the second region 131b. The length SZ5 is formed to the same length as the length L2 of the connecting portion 233e in the Z′-axis direction. The other configuration of the piezoelectric vibrating piece 230e is the same as that of the piezoelectric vibrating piece 230b shown in FIG. In the piezoelectric vibrating piece 230e, since the second length L2 in the Z′-axis direction of the connecting portion 233e is short, the stress applied when the printed circuit board as shown in FIG. 8 is bent is transmitted from the frame portion 132 to the excitation portion 131. It has become difficult.

(Third embodiment)
The connecting portion of the piezoelectric vibrating piece may be connected to the center of the first side 138a of the excitation portion. Hereinafter, the piezoelectric vibrating piece 330 in which the connecting portion is connected to the center of the first side 138a of the excitation portion will be described with reference to FIGS. 10 (a) and 10 (b).

<Configuration of Piezoelectric Vibrating Piece 330>
FIG. 10A is a plan view of the piezoelectric vibrating piece 330. The piezoelectric vibrating piece 330 is formed by an excitation unit 131, a connection unit 333, and a frame unit 132. The excitation unit 131 includes a first region 131a and a second region 131b. An excitation electrode 134 is formed in the first region 131a, and a slit 337 is formed in the second region 131b. In addition, the connecting portion 333 is connected to the center of the first side 138 a of the excitation portion 331. The slit 337 is formed in the + X-axis direction of the connecting portion 333 and is not connected to the through hole 136. In the piezoelectric vibrating piece 330, the extraction electrode 335 extracted from the excitation electrode 134 formed on the surface on the + Y′-axis side is extracted to the frame portion 132 via the + Z′-axis side of the slit 337 and the connecting portion 333. Further, from the surface on the + Y′-axis side through the side surface 135a that extends in the + Z′-axis direction and the + X-axis direction and faces the through hole 136 of the frame portion 132 and includes the corners on the + X-axis side and the + Z′-axis side − The surface is pulled out to the surface on the Y′-axis side, and is pulled out to the corner portion on the + Z-axis side on the + X-axis side of the surface on the −Y′-axis side of the frame portion 132. In addition, the extraction electrode 335 extracted from the excitation electrode 134 formed on the surface at the −Y′-axis side is extracted to the frame portion 132 via the −Z′-axis side of the slit 337 and the connecting portion 333, and −Z ′. It extends in the axial direction and is drawn out to the −Z′-axis-side corner of the −X′-axis side surface of the frame 132 on the −Y′-axis-side surface. Other configurations of the piezoelectric vibrating piece 330 are the same as those of the piezoelectric vibrating piece 130.

  FIG. 10B is a plan view of the piezoelectric vibrating piece 330 on which no electrode is formed. The length of the connecting portion 333 in the Z′-axis direction is formed to the second length L2, and the length of the slit 337 in the Z′-axis direction is formed to the length SZ6. The length SZ6 is the same length as the second length L2 that is the length of the connecting portion 333 in the Z′-axis direction. Therefore, the stress generated on the −X axis side of the connecting portion 333 and the slit 337 is not easily transmitted to the first region 131a.

(Fourth embodiment)
Two connecting portions of the piezoelectric vibrating piece may be formed and connected to the exciting portion at two locations. Hereinafter, the piezoelectric vibrating piece 430 formed with two coupling portions and coupled to the excitation portion at two locations will be described with reference to FIGS. 11 (a) and 11 (b).

<Configuration of Piezoelectric Vibrating Piece 430>
FIG. 11A is a plan view of the piezoelectric vibrating piece 430. The piezoelectric vibrating piece 430 includes an excitation part 131, a connection part 433, and a frame part 132. The excitation unit 431 has a first region 131a and a second region 131b. Excitation electrodes 134 are formed on the surfaces of the first region 131a on the + Y′-axis side and the −Y′-axis side. The second region 131b has a first side 138a that is a side on the −X axis side of the excitation unit 131, and a slit 437 is formed therein. The connecting portion 433 is connected at two locations, the end on the + Z′-axis side and the end on the −Z′-axis side of the first side 138a, and the slits 437 are formed in the + X-axis direction of each connecting portion 433, respectively. . The extraction electrode 435 extracted from the excitation electrode 134 formed on the + Y′-axis side is extracted to the frame portion 132 through the second region 131b and the + Z′-axis side connection portion 433, and Proceed in the + Z ′ axis direction and the + X axis direction. Then, the frame part 132 is pulled out from the surface on the + Y′-axis side to the surface on the −Y′-axis side by the side surface 135a including the corner portion facing the through hole 136 on the + Z′-axis side on the + X-axis side of the frame portion 132, and −Y′-axis It is pulled out to the corner of the + Z′-axis side on the + X-axis side of the side surface. The extraction electrode 435 extracted from the excitation electrode 134 formed on the −Y′-axis side is extracted to the frame portion 132 through the second region 131 b and the −Z′-axis side connection portion 433, and the frame portion 132. Of the surface on the −Y′-axis side of the −Z′-axis side of the −X′-side surface.

  FIG. 11B is a plan view of the piezoelectric vibrating piece 430 on which no electrode is formed. The length of each connecting portion 433 in the Z′-axis direction is formed to a second length L2, and the length of each slit 437 in the Z′-axis direction is the same length as the second length L2. It is formed in SZ7. In the piezoelectric vibrating piece 430, the excitation portion 131 and the frame portion 132 are connected by the two connecting portions 433, thereby improving the connection strength between the exciting portion 131 and the frame portion 132, and the impact resistance of the piezoelectric vibrating piece 430. Will improve.

  The optimum embodiment of the present invention has been described in detail above. However, as will be apparent to those skilled in the art, the present invention can be implemented with various modifications and variations within the technical scope thereof.

  For example, in the above embodiment, the first side is formed shorter than the second side, but the first side may be formed longer than the second side.

  In the above embodiment, the case where the piezoelectric vibrating piece is an AT-cut crystal vibrating piece has been described. However, the present invention can be similarly applied to a BT cut that vibrates in the thickness-slip mode. Further, the piezoelectric vibrating piece can be basically applied not only to a quartz material but also to a piezoelectric material including lithium tantalate, lithium niobate, or piezoelectric ceramic.

DESCRIPTION OF SYMBOLS 100 ... Piezoelectric device 110 ... Lid 111, 121 ... Recessed part 112, 122 ... Bonding surface 120 ... Base 123 ... Connection electrode 124 ... Mounting terminal 125 ... Side electrode 126 ... Castellation 130, 230a, 230b, 230c, 230d, 230e, 330 430 ... Piezoelectric vibrating piece 131 ... Excitation part 132 ... Frame part 133, 233d, 233e, 333 ... Connection part 134 ... Excitation electrode 135, 335, 435 ... Extraction electrode 136 ... Through-hole 137, 137a, 137c, 137d, 137e, 337, 437 ... slit 138a ... first side 138b ... second side 141 ... sealing material 200 ... printed circuit board 231 ... mesa portion

Claims (7)

A rectangular-shaped excitation unit that extends in a first direction and has a pair of second sides extending in a second direction perpendicular to the first direction and a first side having a length formed in the first length;
A frame surrounding the excitation unit;
A coupling portion that couples the first side of the excitation unit and the frame portion, and a length in the first direction is a second length;
The excitation part includes a rectangular first region where excitation electrodes are formed on both main surfaces, a slit extending through the main surfaces of the excitation part and extending in the first direction, and the first side. A rectangular second region formed by being sandwiched between an end of the first region side and the first side,
The slit is formed at a position moved from the first side by a third length in the second direction of the connecting portion;
The piezoelectric vibrating piece, wherein the second length is smaller than the first length, and the length of the slit in the first direction is not less than the second length and not more than the first length.   The piezoelectric vibrating piece according to claim 1, wherein the second side is longer than the first side. The connecting portion is connected to one end of the first side,
3. The piezoelectric vibrating piece according to claim 1, wherein the slit is formed by penetrating the second side connected to an end of the first side to which the connecting portion is connected. The connecting portions are respectively connected to both ends of the first side;
The slits extending in the second direction of the connecting portions are formed through the second sides connected to ends of the first sides to which the connecting portions are connected, respectively.
The piezoelectric vibrating piece according to claim 1, wherein the slits are separated from each other. The connecting portion is connected to the center of the first side;
The piezoelectric vibrating piece according to claim 1, wherein the slit does not penetrate through the pair of second sides.   6. The piezoelectric vibrating piece according to claim 1, wherein the third length is smaller than the second length. The piezoelectric vibrating piece according to any one of claims 1 to 6,
A lid joined to one main surface of the frame portion of the piezoelectric vibrating piece;
A base bonded to the other main surface of the frame portion of the piezoelectric vibrating piece;
Piezoelectric device including: