JPH051149Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field) In recent years, the demand for piezoelectric vibrators has been increasing, and they are particularly widely used as clock sources for microcomputers. The present invention relates to this piezoelectric vibrator, and more specifically relates to the connection between a piezoelectric vibrating element plate and a lead terminal.

(Conventional technology) The prior art will be explained with reference to FIGS. 2a and 2b.

The piezoelectric vibrating plate 71 is made by cutting a polarized piezoelectric ceramic plate into a rectangular shape so as to perform vertical vibration, and has an excitation electrode 7 approximately at the center of the front and back plate surfaces.
2 (74 on the back surface) and an extraction electrode 73 drawn out to the lower end surface of the piezoelectric vibrating blank following this excitation electrode.
(75 on the back side) is formed. Platy lead terminals are brought into contact with the front and back surfaces of the lead electrodes 73 and 75 formed on the front and back surfaces of the piezoelectric vibrating element 71, respectively, and then the enlarged view of the lead terminal connection portion shown in FIG. 2b is shown. As shown in FIG. 3, a paste-like solder (a paste-like mixture of fine particle solder and flux) 62 is applied to this abutting portion and heated and melted to establish an electrical and mechanical connection. Although not shown, the piezoelectric vibrating element 71 is placed in a state where a space is provided only in the central part (main vibrating part) of the piezoelectric vibrating element 71.
1 and part of the lead terminals 76 and 77 were covered with a resin mold.

However, according to the above embodiment, in order to strengthen the mechanical bond between the piezoelectric vibrating element 71 and the lead terminals 76 and 77, a large amount of paste solder is inevitably applied. The flow reaches near the center of the vibrating plate, and the crystal impedance of the piezoelectric vibrator itself deteriorates.
This had the disadvantage of adversely affecting electrical characteristics. Further, generally, the lead terminals 76 and 77 are formed into a lead frame and arranged in a row at a predetermined interval, but when installing the piezoelectric vibrating plate 71 between a pair of lead terminals, positioning is not easy. The bottom side of the piezoelectric vibrating plate 71 may not be perpendicular to the direction in which the lead terminals 76, 77 stand, but may be installed at an angle, and the tips of the lead terminals 76, 77 may interfere with the piezoelectric vibration. The overlapping portion of the blank plates 71 was smaller than desired, making it impossible to obtain sufficient mechanical bonding, and also adversely affecting the vibration of the piezoelectric vibrating blank plates.

(Purpose of the invention) The present invention was made in view of the above circumstances, and it is possible to eliminate the negative influence of solder on the piezoelectric vibrating element, and to make it possible to accurately and easily position the piezoelectric vibrating element on the lead terminal. The object is to provide a piezoelectric vibrator.

(Structure of the invention) According to the invention, the support structure of a piezoelectric vibrator is provided by bringing a plate-shaped lead terminal into contact with the extraction electrode of a rectangular piezoelectric vibrating element having excitation electrodes and extraction electrodes on the front and back surfaces, and applying solder to the piezoelectric vibrator. electrical and mechanical connection is made, and the extraction electrode is pulled out near the corner of the piezoelectric vibrating blank, and a part of the tip of the plate-shaped lead terminal is attached to two continuous sides of the outer periphery of the piezoelectric vibrating blank. It is characterized by extending along the length.

(Embodiment of the invention) An embodiment of the invention is shown in the front view of FIG.
This will be explained with reference to the plan view shown in FIG. b.

The piezoelectric vibrating blank plate 12 is formed by cutting a piezoelectric ceramic plate polarized into a rectangular shape so as to perform thickness shear vibration, and has a pair of excitation electrodes on the front and back surfaces of the piezoelectric ceramic plate. On the front surface of this piezoelectric vibrating element, excitation electrodes 41 are formed all the way in the width direction from one end in the long side direction to a predetermined position including the center, and on the back surface, excitation electrodes 42 are formed from the other end in the same manner. It is formed completely in the width direction up to a predetermined position including the central part. Therefore, the electrode portion formed at the end in the long side direction serves as an extraction electrode. The tip portions of the two plate-shaped lead terminals 51, 55 each consist of a cutting edge portion 52, 56 and a horizontally extending portion 53, 57 extending only inwardly, and wide portions 54, 58 are provided below the tip portion. It is provided to prevent the flow of resin during resin mold coating. Lead terminal 5
The connections 1 and 55 are made by aligning the outer sides of the leading edge parts 52 and 56 and the bottom sides of the horizontally extending parts 53 and 57 with a part of the outer periphery (both short sides and the bottom side) of the piezoelectric vibrating plate 12 so that they overlap each other. Connect by soldering. Although not shown, the molten solder approaches the shape of the tip of the lead terminal due to the surface tension, thereby making the joint stronger. Furthermore, if the amount of paste solder applied is too large, the excess paste solder can be scraped off with a spatula or the like.

The present invention may have a structure in which the lead terminals are connected only on the front surface, and in this case, it is necessary to route the lead electrode on the back surface to the front surface.

(Effect of the invention) According to the invention, the extraction electrode is drawn out near the corner of the piezoelectric vibrating blank, and a part of the tip of the plate-like lead terminal is connected to two continuous areas on the outer periphery of the piezoelectric vibrating blank. Since it is configured to extend along the sides, the tip of one lead terminal extends on both the vertical and horizontal sides of the piezoelectric vibrating plate, making it extremely easy to position the piezoelectric vibrating plate. A piezoelectric vibrator with stable electrical characteristics that allows for stable electrical and mechanical connections without the piezoelectric vibrating plate being connected at an angle, the connection shifting laterally, or the connection becoming shallow. can be provided.

[Brief explanation of the drawing]

1a and 1b are views showing an embodiment of the present invention, and FIGS. 2a and 2b are views showing a conventional example. 12, 71...Piezoelectric vibrating plate, 51, 55, 7
6, 77... Lead terminal, 53, 57... Horizontal extension part.

Claims (1)

[Scope of utility model registration request] A piezoelectric vibrator in which a plate-shaped lead terminal is brought into contact with the lead electrode of a rectangular piezoelectric vibrating plate having excitation electrodes and lead electrodes on the front and back surfaces, and an electrical and mechanical connection is made by soldering, The electrode is drawn out near the corner of the piezoelectric vibrating blank, and a part of the tip of the plate-shaped lead terminal extends along two continuous sides of the outer periphery of the piezoelectric vibrating blank. A support structure for a piezoelectric vibrator.