JPH0221791Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a vibrator configured using a piezoelectric vibrator that performs area vibration, and mainly relates to a metal piece that presses the piezoelectric vibrator from both sides.

As shown in the exploded tactile view of FIG. 1, a conventional vibrator of this type includes a flat metal piece 4 having a protrusion 2 integrally formed with a lead 3, a square piezoelectric vibrator 5,
In order to elastically press the piezoelectric vibrator 5 together with the metal piece 4, the portion facing the piezoelectric vibrator 5 is curved downward from the periphery in a dome shape, and a protrusion 7 is provided on the curved portion 6. The lead 8 and the metal pieces 9 formed as one body are stacked one after another and housed in the box body 1 made of synthetic resin, and finally the box body 1 is closed with a flat lid 10.
is configured to seal. Piezoelectric vibrator 5
is elastically pressed at its center by the projections 2 and 7 from the front and back, and the surrounding vibration nodes are brought into contact with the columnar parts 11 located symmetrically at four locations on the inner surface of the box body 1. Supported. Reference numerals 12 and 13 are grooves in the box body 1 into which the leads 3 and 8 are fitted, respectively, and 14 and 15 are recesses in the metal pieces 4 and 9, respectively, into which the columnar portion 11 is fitted.

By the way, such a vibrator needs to accurately support the intersection of the diagonals of the piezoelectric vibrator 5 that performs area vibration, that is, the center, to reduce the resonance resistance and to increase Qm, but it is not easy to achieve this accuracy. do not have. FIG. 2 is an assembled plan view of the vibrator when the lid 10 is removed. Unlike the metal piece 4 whose periphery is completely in contact with the inner surface of the box body 1, the metal piece 9 is inside the box body 1. A spacing D exists between the side surface and the side surface to enable elastic deformation. When the lid 10 is put on, the curved portion 6 is elastically deformed, and the piezoelectric vibrator 5 of the metal piece 9
The entire area facing the area expands in all directions. Since the lead 8 also moves laterally at this time, it is necessary to make the width of the groove 13 wider than the width of the lead 8. If the widths are the same, it would be difficult to fit the leads 8 into the grooves 13 without forcefully bending them to prevent movement when the lid 10 is placed on the lead 8. Therefore, the metal piece 9 can be moved laterally as desired by the difference in width between the groove 13 and the lead 8. Further, the lead 8 can also move in the length direction due to the existence of the interval D. As described above, the metal piece 9 easily moves in the horizontal direction, and it is difficult to position the protrusion 7 at the center of the piezoelectric vibrator 5 unlike the protrusion 2 of the metal piece 4 which is completely fixed. Of course, the metal piece 9 can be formed into a flat plate shape like the metal piece 4 to prevent movement, but in that case, it is necessary to separately arrange a spring material on the metal piece 9 in order to obtain elastic force. This increases the material cost and increases the size of the vibrator.

The present invention improves these conventional drawbacks and provides a vibrator that can accurately support the center of the piezoelectric vibrator from both sides.

In this invention, a piezoelectric vibrator that performs area vibration is housed in a box with the center of its main surface being elastically pressed by other metal pieces from both sides, and the leads of each metal piece are connected to the outside from the box. In the vibrator protruding to the top, the metal piece on one side curves the portion facing the piezoelectric vibrator into a dome shape, and the lengths of diagonal lines connecting the four corners of the metal piece facing the piezoelectric vibrator are made different. It is characterized by having leads formed at the shorter diagonal corners.

Embodiments of the vibrator of the present invention will be described below with reference to FIGS. 3, 4, 5, and 6.
Figure 3 is an exploded perspective view, Figure 4 is an assembled perspective view, and Figure 5 is an exploded perspective view.
The figure is an assembled plan view with the lid removed, and FIG. 6 is an assembled cross-sectional view taken along line A-A' in FIG. 5.

3 to 6, 20 is a synthetic resin box, 21 and 23 are metal pieces, 22 is a piezoelectric vibrator made of piezoelectric ceramic, and 24 is a synthetic resin lid.

The box body 20 has a substantially square recess 2 open to the upper side.
5, and a semi-cylindrical columnar portion 26 that extends inward is formed on each side of the inner surface 42. The metal piece 21 is a flat plate consisting of an elongated part serving as a lead 27 and a substantially square part 30 facing the piezoelectric vibrator 22, and a protrusion 28 is formed in the center of the part 30. The metal piece 21 connects the portion 30 to the recess 2
The lead 27 is fitted into the bottom surface 31 of the box body 20 and housed in the recess 25, and the lead 27 projects horizontally from the groove 33 of the box body 20. The portion 30 is 3 other than the lead 27 side.
The sides completely abut the inner surface 42 as shown in FIG. Note that 29 is a recess into which the columnar portion 26 is fitted. A piezoelectric vibrator 22 is placed on the metal piece 21 . The piezoelectric vibrator 22 has electrodes 3 on its front and back main surfaces.
2 is formed, and the projection 28 contacts the metal piece 21 at the center of the back main surface, and the periphery abuts the columnar part 26 as shown in FIG. The abutting position corresponds to a vibration node of the piezoelectric vibrator 22. A metal piece 23 is placed on the piezoelectric vibrator 22 .

The metal piece 23 consists of an elongated portion that serves as a lead 34 and a substantially rectangular portion 35 that faces the piezoelectric vibrator 22. A protrusion 36 is formed in the center of the portion 35, and the entire center portion is raised by curving from the periphery into a dome shape as shown in FIG. When the piezoelectric vibrator 25 is sealed, the periphery of the portion 35 is pressed by the lid 24 and the curved portion 43 is deformed, so that a protrusion 36 is formed to elastically press the center of the front main surface of the piezoelectric vibrator 22. ing. Further, the lengths of the diagonal line L1 connecting the four corners of the portion 35 and the diagonal line L2 are different, and the diagonal line L2 connecting the corner where the lead 34 is formed is shortened. As a result, the horizontal position of the corner where the lead 34 is formed is lower than the corner connected by the diagonal line L1. The lead 34 can be positioned and fitted at the bottom of the groove 41 of the box body 20, which is formed to have the same width before the lid 24 is attached. Furthermore, the lead 34 is provided with two protrusions 37 and 38 formed by widening its cross section, and when the lead 34 is fitted into the groove 41, the protrusions 37 and 38 form the box body 20, respectively. It is locked on the inside and outside of the side surface 39. Note that 44 is a recess into which the columnar portion 26 is fitted.

By covering the lid 24 over the metal piece 23 stored in the recess 25 in this way, the recess 25 is
is sealed.

The lid 24 has a prismatic convex portion 40A and a convex portion 40B formed at positions corresponding to the grooves 33 and 41 of the box body 20, and the convex portion 40A is formed in the groove 33 in which the lead 27 is fitted, and the convex portion 40B. are formed so as to fit into the grooves 41 into which the leads 34 are fitted. In FIG. 5, the positions of the protrusions 40A and 40B are indicated by dotted lines.

By configuring the vibrator of the present invention in this way, the metal piece 23 can move in a plane even if there is a gap D between the elastically deforming portion 35 of the metal piece 23 and the inner surface 42 of the recess 25. Never. In particular, due to the length of the diagonal line, the horizontal position of the lead 34 is lower than the corner connected by the long diagonal line L1. This is because the corners connected by the diagonal line L2 are closer to the center than the corners connected by the diagonal line L1, since the metal piece 23 is curved around with substantially the same curvature from the center, that is, the position where the protrusion 36 is located. When the lid 24 is put on, only the corners connected by the diagonal line L1 of the portion 35 of the metal piece 23 are pushed by the lid 24 and spread in the direction of the diagonal line L1. However, the corner connected by the diagonal line L2 is the lid 24.
Since the groove 41 does not come into contact with the lead 34, it does not spread in the direction of the diagonal line L1, and the lead 34 does not move laterally, so the width of the groove 41 can be made the same as the width of the lead 34 from the beginning. When the lid 24 is completely covered, the lead 34 contacts the convex portion 40B, but the lead 34 is already at the bottom of the groove 41 and the diagonal line L
The portion 35 does not widen in one direction. Further, even if the lead 34 is slightly above the bottom of the groove 41 and the convex portion 40B contacts the lead 34 before the lid 24 is completely covered, the corner opposite to the lead 34 side connected by the diagonal line L2 will be the lid 24. Since the portion 35 is not in contact with the portion 35, the portion 35 still does not expand in this direction. Of course, the movement of the lead 34 in the length direction is caused by the protrusion 37 and the protrusion 3.
8 is locked to the side surface 39.
In this way, the projection 36 of the elastically deformable metal piece 23 can always contact the center of the main surface of the piezoelectric vibrator 22 as originally designed.

In addition, it is possible to obtain an excellent resonator with small resonance resistance and large Qm. Needless to say, the variation in characteristics between each vibrator is reduced and the quality during manufacturing is improved. Furthermore, since there is no need to separately arrange a spring material, the price is low and assembly is easy.

[Brief explanation of the drawing]

Fig. 1 is an exploded perspective view of a conventional vibrator, Fig. 2 is an assembled plan view, Fig. 3 is an exploded perspective view showing an embodiment of the vibrator of the present invention, Fig. 4 is an assembled perspective view, and Fig. 5. 6 is an assembled plan view, and FIG. 6 is an assembled sectional view taken along line A-A' in FIG. 5. 1, 20... Box body, 2, 7, 28, 36... Protrusion, 3, 8, 27, 34... Lead, 4, 9, 2
1, 23...metal piece, 5, 22...piezoelectric vibrator,
6,43...Curved part, 10,24...Lid, 1
1, 26... Columnar part, 12, 13, 33, 41...
... Groove, 14, 15, 29, 44... Recess, 25...
... recess, 30, 35... portion, 31... bottom, 3
2... Electrode, 37, 38, 40A, 40B... Convex portion, 39... Side surface, 42... Inner surface.

Claims (1)

[Scope of utility model registration request] A piezoelectric vibrator that performs area vibration is housed in a box with the center of its main surface being elastically pressed by other metal pieces from both sides, and the leads of each metal piece protrude from the box to the outside. In the vibrator, the metal piece on one side has the part facing the piezoelectric vibrator curved into a dome shape, and the lengths of the diagonals connecting the four corners of the metal piece facing the piezoelectric vibrator are different. A vibrator characterized in that a lead is formed in the short corner of the oscillator.