JP2003037466A - Surface mounting type of piezoelectric oscillator, mounting method therefor, and mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a thin, small, and low-cost surface mounting type of piezoelectric oscillator by removing the short circuit at mounting, while the dimensions in the thickness direction and in width direction of itself are approximate to those of a tubular piezoelectric oscillator, in a surface mounting type of oscillator where the stems of a tubular piezoelectric oscillator, having two pieces of stems at one end are fixed to the lead frame and are insert-molded by resin and the lead frame serves as the electrode of itself and the bottom of that electrode is not covered with resin. SOLUTION: In the surface mounting type of oscillator, where the stems of the tubular piezoelectric oscillator having two pieces of stems at one end are fixed to the lead frame and are insert-molded by resin and the lead frame serves as the electrode of itself and the bottom of that electrode is not covered with resin, the tubular piezoelectric oscillator within itself is positioned, by using a press member in thickness direction installed in an insert molding mold and a press member for positioning the flank in longitudinal direction of the tubular piezoelectric oscillator.

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, a method for manufacturing the same and a mold.

[0002]

2. Description of the Related Art With the progress of surface mounting of electronic parts, the number of piezoelectric vibrators, which are one of the electronic parts, is also increasing. The surface mount type structure of a piezoelectric vibrator is roughly classified into a structure in which a piezoelectric element is directly mounted in a case compatible with surface mounting and a structure in which a cylindrical piezoelectric vibrator is fixed to a lead frame forming an electrode and molded with resin. It The present invention relates to the latter.

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 of the cylindrical piezoelectric vibrator insert-molded in a resin and a lead frame are shown by dotted lines. is doing. Surface mount type piezoelectric vibrator
Step of fixing the stems 2 and 3 of the cylindrical piezoelectric vibrator 1 to the terminal portions 4 and 5 which become the electrodes of the surface mount piezoelectric vibrator of the lead frame by resistance welding or laser welding, the electrode 4,
5, the step of insert molding with resin 8 leaving the terminals 5 and 6 and 7 from the lead frame to the electrodes 4 and 5 and the terminals 6 and 7.
Is manufactured by bending the electrodes 4, 5 and the terminals 6, 7 and disposing one end of the electrodes 4, 5 and the terminals 6, 7 under the resin 8.

Mobile products typified by mobile phones are strongly required to be small, thin, and inexpensive, and have a thickness of 0.1 mm, 0.
Various structures have been devised for surface-mounted piezoelectric vibrators in order to achieve miniaturization, thinning, and weight reduction of 1 g. FIG. 6 is a front view of a surface-mounted piezoelectric vibrator that meets the above requirements, and FIG.
Is a bottom view, and the cylindrical piezoelectric vibrator insert-molded inside the resin is indicated by a dotted line. A terminal portion 14 serving as an electrode of the surface mount piezoelectric vibrator 10 of the lead frame;
15 and the terminal portion 16 are arranged on the lower surface of the resin 17, and the upper surfaces of the terminal portions 14 and 15 and the terminal portion 16 serving as electrodes are the resin 1
The structure is fixed to 7. The stems 12 and 13 of the cylindrical piezoelectric vibrator 11 are formed as shown in the figure for connecting and fixing to the electrodes 14 and 15. Compared with the structure of FIG. 1, the electrodes 5, (4) and the terminals 7 (6) are made thinner. Further, the structure is capable of reducing the cost by omitting the bending process of the electrodes and terminals after insert molding.

[0005]

The surface-mounted piezoelectric vibrator described above, which can be made thin and inexpensive, is required to be further downsized. It is possible to further reduce the size by reducing the thickness of the resin in the width direction of the surface-mounted piezoelectric vibrator, but the pressing pin in the thickness direction installed in the conventional insert molding die can be used to With the pressing method and the mold, it is difficult to press the cylindrical piezoelectric vibrator in the center of the molding die in the width direction. The surface of the cylindrical part of the cylindrical piezoelectric vibrator that is insert-molded inside is largely exposed on the lateral surface of the surface-mounted piezoelectric vibrator, and after mounting on the board, it contacts with other parts nearby and causes a short circuit failure. There is a problem that ends up.

An object of the present invention is to mount a stem of a cylindrical piezoelectric vibrator having two stems at one end on a lead frame and insert-mold it with a resin. In the surface mount type piezoelectric vibrator, the lead frame is surface mounted. Of the surface-mounted piezoelectric vibrator whose bottom surface is not covered with resin, and the dimensions of the surface-mounted piezoelectric vibrator in the thickness direction and the width direction are the same as those of the cylindrical piezoelectric vibrator. An object of the present invention is to provide a thin, small, and low-priced surface-mount type piezoelectric vibrator that eliminates short-circuit defects during mounting while making the size close to the size, and a manufacturing method and a mold for the same.

[0007]

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 is insert-molded with a resin, wherein the lead frame is In the surface-mounted piezoelectric vibrator, which becomes the electrode of the surface-mounted piezoelectric vibrator and the lower surface of the electrode is not covered with resin, the pressing member in the thickness direction installed in the insert molding die and the cylindrical piezoelectric vibrator By using the pressing member for positioning the side surface in the longitudinal direction, the cylindrical piezoelectric vibrator in the surface-mounted piezoelectric vibrator is positioned, and thus the surface-mounted piezoelectric vibrator is obtained.

At least the step of fixing the stem of the cylindrical piezoelectric vibrator having two stems at one end to the lead frame, and the insert molding die are used to position and regulate the longitudinal side surface and the thickness direction of the cylindrical piezoelectric vibrator. A method of manufacturing a surface-mounted piezoelectric vibrator including a step and an insert molding step.

A surface mount type piezoelectric vibrator die, in which a stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame and is insert-molded with resin,
The mold is a mold having a member for positioning and regulating the longitudinal side surface and the thickness direction of the cylindrical piezoelectric vibrator.

[0010]

FIG. 4 and FIG. 5 are a front sectional view of an insert molding die of a surface mount type piezoelectric vibrator which is one embodiment of the present invention and a bottom view of a main portion of an upper die. The outer shape of the cylindrical piezoelectric vibrator 20 is shown by a dotted line in the drawing. The insert molding die is formed of an upper die 21 and a lower die 22.
The lower die 22 has a flat surface 22a on which the cylindrical piezoelectric vibrator 20 is attached.
Are formed with projections 25 and 26 that come into contact with the outer peripheral surface of the lower part of the. The upper mold 21 is formed with projections 23, 24 that come into contact with the upper outer peripheral surface of the cylindrical piezoelectric vibrator 20 and projections 27, 28, 29, 30 that come into contact with the longitudinal side surfaces of the cylindrical piezoelectric vibrator 20. There is. The protrusions 23 to 30 may be integrated with the mold or may be separate members.

A stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame. The lead frame is set on the upper surface 22a of the lower mold 22. Next, the upper die 21 is set. When the upper mold 22 is covered, the projections 27 to 30 position the longitudinal side surface of the cylindrical piezoelectric vibrator. Therefore, it is preferable that the protrusions 27 to 30 have a tapered shape on the opening side of the upper mold. Upper mold 21
When the lower die 22 and the lower die 22 are combined, the projections 25 and 26 formed on the lower die in the thickness direction (vertical direction) of the cylindrical piezoelectric vibrator 20.
The positioning is regulated by the projections 23 and 24 formed on the upper mold 21. That is, in this embodiment, the cylindrical piezoelectric vibrator is positioned by the eight protrusions. Resin is injected in this state.

FIG. 3 is a perspective view of a surface mount type piezoelectric vibrator according to the present invention. The cylindrical piezoelectric vibrator 20 insert-molded with the resin 17 has exposed portions positioned by the projections of the mold (four positions in this figure). As can be seen from the positional relationship between the upper die 21 and the cylindrical piezoelectric vibrator 20 shown in FIG. 5, the resin thickness on the longitudinal side surface (shorter direction) of the cylindrical piezoelectric vibrator may be the height of the protrusion. Can be miniaturized.

[0013]

According to the first aspect of the present invention, it is possible to obtain a small-sized surface mount type piezoelectric vibrator in which the surface exposure of the cylindrical piezoelectric vibrator does not vary.

According to the second aspect of the present invention, there is provided a small-sized method of manufacturing a surface-mounted piezoelectric vibrator in which the surface exposure of the cylindrical piezoelectric vibrator does not vary.

According to the third aspect of the present invention, it is possible to obtain a mold for manufacturing a surface-mounted piezoelectric vibrator, which is small and has no variation in surface exposure of the cylindrical piezoelectric vibrator.

[Brief description of drawings]

FIG. 1 is a front view of a typical surface mount piezoelectric vibrator according to a conventional technique.

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

FIG. 3 is a perspective view of a surface-mounted piezoelectric vibrator according to the present invention.

FIG. 4 is a front sectional view of an insert molding die of a surface-mounted piezoelectric vibrator according to an embodiment of the present invention.

FIG. 5: Bottom view of the main part of the upper die

FIG. 6 is a front view of a surface-mounted piezoelectric vibrator.

[Figure 7] Bottom view

[Explanation of symbols]

1 Cylindrical piezoelectric vibrator 2 stems 3 stems 4 electrodes 5 electrodes 6 terminals 7 terminals 8 resin 10 Surface mount piezoelectric vibrator 14 terminal 15 terminals 16 terminals 17 Resin 20 Cylindrical piezoelectric vibrator 21 Upper mold 22 Lower mold 22a flat surface 23 Protrusion 24 protrusions 25 protrusions 26 Protrusion 27 protrusions 28 Protrusion 29 Protrusion 30 protrusions

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) H03H 3/02 H01L 41/08 C 41/22 Z

Claims (3)

[Claims] 1. A surface mount type piezoelectric vibrator, wherein a stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame and is insert-molded with a resin, wherein the lead frame is a surface mount type piezoelectric vibrator. It becomes the electrode of the oscillator,
In the surface mount type piezoelectric vibrator in which the lower surface of the electrode is not covered with resin, a pressing member arranged in the insert molding die in the thickness direction and a pressing member for positioning the longitudinal side surface of the cylindrical piezoelectric vibrator are used. Thus, the surface-mounted piezoelectric vibrator is characterized in that the cylindrical piezoelectric vibrator in the surface-mounted piezoelectric vibrator is positioned. 2. A step of fixing at least a stem of a cylindrical piezoelectric vibrator having two stems at one end to a lead frame, and a longitudinal side surface and a thickness direction of the cylindrical piezoelectric vibrator are positioned by an insert molding die. A method of manufacturing a surface-mounted piezoelectric vibrator, comprising: a step of regulating and a step of insert-molding. 3. A surface mount type piezoelectric vibrator mold, wherein a stem of a cylindrical piezoelectric vibrator having two stems at one end is fixed to a lead frame and is insert-molded with a resin, wherein the mold is a cylindrical piezoelectric vibrator. A metal mold having a member for positioning and controlling the longitudinal side surface and the thickness direction of the vibrator.