JP2001285008A - Surface-mounted piezoelectric vibrator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin, small-sized, and low-priced surface mount type piezoelectric vibrator by improving the fixing force between an electrode and resin, in such a surface-mounted type piezoelectric vibrator that the lead frame of the surface-mounted type piezoelectric vibrator which has stems of a cylindrical piezoelectric vibrator, having the two stems at one end and is formed by insertion molding using resin, fixed to the lead frame serves as the electrode of the surface mount type piezoelectric vibrator and the reverse surface of the electrode is not coated with resin. SOLUTION: The surface-mounted type piezoelectric vibrator is formed by fixing the stems of the cylindrical piezoelectric vibrator, having the two stems at one end to the lead frame and carrying out insertion molding using the resin, the lead frame serves as the electrode of the surface mount type piezoelectric vibrator, and the reverse surface of the electrode is not coated with resin. Part of the electrode center part is cut and raised and then embedded in the resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface mount type piezoelectric vibrator.

[0002]

2. Description of the Related Art The surface mounting of electronic components has progressed, and the number of piezoelectric vibrators, which are one of the electronic components, which are compatible with surface mounting is increasing. The surface mount type structure of a piezoelectric vibrator is roughly divided into a structure in which a piezoelectric element is directly incorporated in a case corresponding to surface mounting, and a structure in which a cylindrical piezoelectric vibrator is fixed to a lead frame constituting electrodes and molded with resin. You. The present invention relates to the latter structure.

FIG. 1 is a front view of a typical surface-mount type piezoelectric vibrator according to the prior art, and FIG. 2 is a top view. The piezoelectric vibrator and the lead frame, which are insert-molded in a resin, are indicated by dotted lines. I have. The surface-mount type piezoelectric vibrator includes a step of fixing the stems 2 and 3 of the piezoelectric vibrator 1 to terminals 4 and 5 serving as electrodes of the surface-mount type piezoelectric vibrator of the lead frame by resistance welding or laser welding. 5, a step of insert molding with the resin 8 leaving the terminals 6 and 7;
A step of separating the electrodes 4, 5 and the terminals 6, 7 from the lead frame, a step of bending the electrodes 4, 5 and the terminals 6, 7 and arranging one end of the electrodes 4, 5 and the terminals 6, 7 below the resin 8 It is manufactured by

[0004] Mobile products such as mobile phones are strongly required to be small, thin, and inexpensive.
Various structures have been devised for the surface mount type piezoelectric vibrator in order to achieve a reduction in size, thickness and weight of 1 g. FIG. 3 is a front view of the surface mount type piezoelectric vibrator according to the present invention, and FIG. 4 is a bottom view, in which the piezoelectric vibrator insert-molded inside the resin is indicated by a dotted line. The terminal portions 14 and 15 and the terminal portions 16 serving as electrodes of the surface-mount type piezoelectric vibrator 10 of the lead frame are disposed on the lower surface of the resin 17, and the upper surfaces of the terminal portions 14 and 15 and the terminal portions 16 serving as the electrodes correspond to the resin 17. The structure is fixed. Stem 1 of piezoelectric vibrator 11
2 and 13 are formed as shown in the figure to connect and fix to the electrodes 14 and 15. Compared to the structure of FIG.
(4) and the thickness of the terminal 7 (6) are reduced in thickness. Further, the electrode and the terminal after the insert molding are not required to be bent, so that the cost can be reduced.

[0005]

The above-mentioned surface-mount type piezoelectric vibrator, which can be made thinner and less expensive, has a problem that the fixed area between the electrode and the resin is reduced as the size is reduced. Since the adhesive strength between the resin and the resin becomes weak, the electrodes are peeled off from the resin in a reliability test or the like.

An object of the present invention is to provide a surface-mount type piezoelectric vibrator in which a stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame and insert-molded with a resin. A low-cost, low-cost, surface-mount type piezoelectric vibrator that serves as an electrode of a piezoelectric vibrator and has a lower surface that is not covered with resin. Is to provide.

[0007]

A cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame, and the lead frame of the surface mounted piezoelectric vibrator is insert-molded with a resin. Surface of a surface-mounted piezoelectric vibrator, in which the lower surface of the electrode is not covered with resin, and a part of the center of the electrode is cut out and raised to be buried in the resin. Vibrator.

In the above-mentioned surface-mount type piezoelectric vibrator, the stem of the piezoelectric vibrator is fixed to the upper surface of the hole formed by the notch rising.

[0009]

FIG. 6 is a bottom view of a surface mount type piezoelectric vibrator according to an embodiment of the present invention, in which a piezoelectric vibrator insert-molded inside a resin is indicated by a dotted line. FIG. 5 is a front sectional view, and is an AA section of FIG. When the electrodes 21, 22 and the terminals 23 of the lead frame are formed, rising portions 21a (not shown), 22a, and 23a are formed at the center of the electrodes 21, 22, and the terminals 23. The rising portion is formed so as to be buried in the resin 17 during insert molding as shown in FIG. 5, and preferably has a rising angle of about 45 degrees with respect to the bottom surface. The rising portion is preferably located at the center of the electrode.
In the case where the squares 1 and 22 are square, the peeling strength can be increased by setting the rising portion to be a central portion that is not deviated vertically and horizontally. When the terminals 23 are rectangular as in the present embodiment, the peel strength can be increased by forming a plurality of (two in FIG. 6) rising portions.

The stems 12 and 13 of the piezoelectric vibrator are fixed to face the upper surfaces of the holes 21b and 22b formed by the notch rising. As shown in FIG. 5, the resin wraps around the stem 13, so that the resin is firmly fixed to the stems 12, 13 fixed to the electrodes 21, 22, and as a result, the peel strength of the electrode is improved.

[0011]

According to the present invention, a part of the center of the electrode is cut out and raised, and the electrode is buried in the resin, so that the adhesion between the electrode and the resin is improved and the peeling of the electrode in a reliability test or the like can be prevented.

The fixing force between the electrode and the resin can be improved by fixing the stem of the piezoelectric vibrator so as to face the upper surface of the hole formed by cutting up the notch. The size can be reduced.

[Brief description of the drawings]

FIG. 1 is a front view of a typical surface mount type piezoelectric vibrator according to the related art.

FIG. 2 is a top view of a typical surface mount type piezoelectric vibrator according to the related art.

FIG. 3 is a front view of the surface mount type piezoelectric vibrator according to the present invention.

FIG. 4 is a bottom view of the surface mount type piezoelectric vibrator according to the present invention.

5 is a front sectional view of a surface mount type piezoelectric vibrator according to an embodiment of the present invention, and is a sectional view taken along line AA of FIG. 6;

FIG. 6 is a bottom view of a surface-mount type piezoelectric vibrator according to an embodiment of the present invention.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 piezoelectric vibrator 2 stem 3 stem 4 electrode 5 electrode 6 terminal 7 terminal 8 resin 10 surface mount type piezoelectric vibrator 11 piezoelectric vibrator 12 stem 13 stem 14 electrode 15 electrode 16 terminal portion 17 resin 21 electrode 21a rising portion 21b hole 22 electrode 22a rising part 22b hole 23 terminal 23a rising part

Claims (2)

[Claims] 1. A surface-mounted piezoelectric vibrator in which a stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame and insert-molded with resin, wherein the lead frame is a surface-mounted piezoelectric vibrator. A surface mount type piezoelectric vibrator in which the lower surface of the electrode is not covered with a resin, and a part of the center portion of the electrode is cut out and raised to be buried in the resin. Piezoelectric vibrator. 2. The surface mount type piezoelectric vibrator according to claim 1, wherein a lead wire of the piezoelectric vibrator faces and is fixed to an upper surface of a hole formed by raising the notch.