JP2004312298A - Surface mounted piezoelectric vibrator and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a thin, small-sized and inexpensive surface mounted piezoelectric vibrator by eliminating defects peculiar to an insertion-molded surface mounted piezoelectric vibrator and the surface mounted piezoelectric vibrator for which the reed of a reed type cylindrical piezoelectric vibrator is cut and formed in the surface mounted piezoelectric vibrator. <P>SOLUTION: For the surface mounted piezoelectric vibrator, thermoplastic resin having planes at one or more planes is provided around the cylinder part of the reed type cylindrical piezoelectric vibrator having two reeds at one end. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a surface mount type piezoelectric vibrator and a method for manufacturing the same.
[0002]
[Prior art]
With the progress of surface mounting of electronic components, the number of piezoelectric vibrators, which are one of the electronic components, corresponding to surface mounting is increasing. The surface mount type structure of the piezoelectric vibrator is composed of a structure in which a piezoelectric element is directly incorporated in a case corresponding to surface mounting, and a lead type cylindrical piezoelectric vibrator, which is fixed to a lead frame and insert-molded with resin to form the lead frame. Or a structure in which the leads of the lead-type cylindrical piezoelectric vibrator are cut and formed. The present invention relates to the latter structure.
[0003]
FIG. 1 is a front view of a typical surface mount type piezoelectric vibrator insert-molded with a resin according to the prior art, and FIG. 2 is a top view showing a lead-type cylindrical piezoelectric vibrator insert-molded inside a resin and a lead. The frame is displayed with a dotted line. The lead type cylindrical piezoelectric vibrator is a general vibrator in which a vibrating piece is fixed to an airtight terminal having two leads and sealed with a cylindrical sealing tube. The surface mount type piezoelectric vibrator fixes the leads 2 and 3 of the lead type cylindrical piezoelectric vibrator 1 to terminal portions 4 and 5 serving as electrodes of the surface mount type piezoelectric vibrator of the lead frame by resistance welding or laser welding or the like. Process, a process of insert molding with the resin 8 while leaving the electrodes 4, 5 and the terminals 6, 7, a process of separating the electrodes 4, 5 and the terminals 6, 7 from the lead frame, and bending the electrodes 4, 5, and the terminals 6, 7 Then, it is manufactured by a process in which the electrodes 4 and 5 and one end of the terminals 6 and 7 are arranged below the resin 8. The model number, manufacturing date, etc. are printed on the upper surface of the surface mount type piezoelectric vibrator. (For example, see Patent Document 1)
[0004]
FIG. 3 is a front view of a surface mount type piezoelectric vibrator in which leads of a typical lead type cylindrical piezoelectric vibrator according to the prior art are cut and formed, and FIG. 4 is a top view of the lead type cylindrical piezoelectric vibrator 1. Is manufactured by cutting and forming the leads 12 and 13 of FIG. The model number, manufacturing date, etc. are printed on the surface of the cylindrical piezoelectric vibrator. (For example, see Patent Document 2)
[0005]
[Patent Document 1]
Japanese Patent Application Laid-Open No. 08-023252 [Patent Document 2]
JP 2000-155178 A
[Problems to be solved by the invention]
In the surface mount type piezoelectric vibrator insert-molded with the above-mentioned resin, the lead type cylindrical piezoelectric vibrator is deformed or broken by the resin pressure during insert molding, or the resin surface warps due to resin shrinkage after molding. There is a problem that appearance is poor such as occurrence of sink marks and insufficient filling of the resin, such as exposure of the lead type cylindrical piezoelectric vibrator. In the case of a surface mount type piezoelectric vibrator in which the lead of a lead type cylindrical piezoelectric vibrator is cut and formed, the vibrator surface is a curved surface. In this case, there is a problem that a cut and forming defect occurs, a user makes a suction error during mounting, and a mounting position shift occurs.
[0007]
SUMMARY OF THE INVENTION An object of the present invention is to provide a surface mount type piezoelectric vibrator which has a defect peculiar to a surface mount type piezoelectric vibrator in which leads of an insert molded surface mount type piezoelectric vibrator and a lead type cylindrical piezoelectric vibrator are cut and formed. An object of the present invention is to provide a thin, small, and inexpensive surface mount type piezoelectric vibrator.
[0008]
[Means for Solving the Problems]
A surface mount type piezoelectric vibrator is provided in which a thermoplastic resin having one or more flat surfaces is provided around a cylindrical portion of a lead type cylindrical piezoelectric vibrator having two leads at one end. Preferably, the lead type cylindrical piezoelectric vibrator is a surface-mounted piezoelectric vibrator in which the tip of the lead type cylindrical piezoelectric vibrator is exposed from the thermoplastic resin.
[0009]
A step of covering at least one end of a lead-type tubular piezoelectric vibrator having two leads at one end with a tubular thermoplastic resin, and heating the thermoplastic resin to form one or more flat portions; And a step of cutting and forming the lead with reference to the plane portion.
[0010]
BEST MODE FOR CARRYING OUT THE INVENTION
5 is a front view of a surface mount type piezoelectric vibrator according to an embodiment of the present invention, FIG. 6 is a top view, and FIG. 7 is a side view. A lead type cylindrical piezoelectric vibrator 11, a thermoplastic resin 17 having a flat surface 18 formed on the upper surface and a flat surface 19 formed on the lower surface by heating, and cut and formed leads 22 and 23 are shown. FIG. 8 is a perspective view of a thermoplastic resin molded product 20 covering a surface-mount type piezoelectric vibrator according to an embodiment of the present invention.
[0011]
FIG. 10 is a diagram in which a surface-mount type piezoelectric vibrator according to one embodiment of the present invention is fixed to a substrate. When the length of the thermoplastic resin molded product 20 is shorter than the length of the lead-type cylindrical piezoelectric vibrator 11, the tip of the lead-type cylindrical piezoelectric vibrator 11 is exposed from the thermoplastic resin 17, and the substrate 26 is mounted at the time of mounting. Can be fixed with the solder 25.
[0012]
FIG. 9 is a front view of a surface mount type piezoelectric vibrator according to another embodiment of the present invention, which is in the middle of a manufacturing process. After the lead type cylindrical piezoelectric vibrator 11 is completed, a state in which a thermoplastic resin molded product 20 is manually or automatically placed on the lead type cylindrical piezoelectric vibrator 11 is shown. The space in which the lead-type cylindrical piezoelectric vibrator 11 enters the thermoplastic resin molded product 20 is larger than the diameter of the lead-type cylindrical piezoelectric vibrator 11. It does not get stuck when the article 20 is put on, and can be worked efficiently both manually and with an automatic machine, so that the lead type cylindrical piezoelectric vibrator 11 and the stems 22 and 23 are not deformed. At this time, when the lead type cylindrical piezoelectric vibrator 11 is attached to the dedicated jig 9 and is in a vertical state, the work is easier.
[0013]
FIG. 11 is a front view of a heating plate according to one embodiment of the present invention, and FIG. 12 is a top view of the heating plate according to one embodiment of the present invention. The thermoplastic resin molded product 20 is sandwiched by a set of heating plates 30 in which two sheets heated by a heater face each other in parallel with the leads 22 and 23 of the lead type cylindrical piezoelectric vibrator 11, and the thermoplastic resin is heated. The molded product 20 is deformed while being melted, crushed to a certain size, and then the heating plate 30 is slowly removed. Thus, the lead-type cylindrical piezoelectric vibrator 11 and the thermoplastic resin 17 are fixed, and flat surfaces 18 and 19 are formed on the surface of the thermoplastic resin 17. At this time, the heating plate 30 has positioning protrusions 31, 32, 33, 34, 35, 36, 37, 38 (36 and 38 are not shown) for the lead type cylindrical piezoelectric vibrator 11, and the lead type cylindrical piezoelectric vibrator 11 is provided. The displacement of the vibrator 11 does not cause a defect, and the thickness of the flat surfaces 18, 19 of the thermoplastic resin 17 is adjusted by the dimensions of the projections 31, 32, 33, 34, 35, 36, 37, 38. By setting the dimensions to obtain the minimum strength, it is possible to further reduce the size and thickness.
[0014]
In addition, the lead-type cylindrical piezoelectric vibrator 11 may be deformed or broken by the resin pressure during insert molding, or the resin surface may be warped or shrunk due to resin shrinkage after molding, or the lead-type cylindrical mold may be insufficiently filled with resin. The appearance defect such as the exposure of the piezoelectric vibrator 11 is eliminated.
[0015]
Thereafter, the leads 22 and 23 are cut and formed with reference to the planes 18 and 19 of the thermoplastic resin 17. At this time, rotation and misalignment of the lead-type cylindrical piezoelectric vibrator 11 are eliminated, and cut-and-forming defects of the leads 22 and 23 are reduced. The problems that occur are eliminated.
[0016]
In the description of the present embodiment, the cross-sectional shape of the thermoplastic resin molded product 20 has been described as a cylindrical shape, but the outside may be a square and the inside is a circle, the outside is a circle and the inside is a square, or the outside and the inside may be a rectangle. In addition, the shape may be such that a resin molding die can be manufactured at low cost and molding defects do not occur. Further, the method of heating the thermoplastic resin molded article 20 has been described using the heating plate 30 using a heater, but other heating methods such as ultrasonic heating or high frequency induction heating may be used.
[0017]
【The invention's effect】
According to the present invention, a lead-type cylindrical piezoelectric vibrator is deformed or broken by resin pressure during insert molding, or warpage or sink occurs on the resin surface due to resin shrinkage after molding, and lead-type cylinder is insufficiently filled with resin. Surface-mounted crystal resonators, which reduce appearance defects such as the exposure of a piezoelectric resonator and cut and forming defects of leads, and eliminate user-induced suction errors and mounting position deviations due to the curved shape of the suction surface. can get.
[0018]
According to the present invention, a lead-type cylindrical piezoelectric vibrator is deformed or broken by resin pressure during insert molding, or warpage or sink occurs on the resin surface due to resin shrinkage after molding, and lead-type cylinder is insufficiently filled with resin. The appearance defects such as the exposure of the die-type piezoelectric vibrator and the cut and forming defects of the lead are reduced, and the user does not have a suction error at the time of mounting due to the curved shape of the suction surface and the mounting position is not shifted. A surface mount type crystal unit that can be fixed can be obtained.
[0019]
According to the present invention, a lead-type cylindrical piezoelectric vibrator is deformed or broken by resin pressure during insert molding, or warpage or sink occurs on the resin surface due to resin shrinkage after molding, and lead-type cylinder is insufficiently filled with resin. Appearance defects, such as the exposure of the piezo-type piezoelectric vibrator, and lead cut-and-forming defects are reduced. A manufacturing method is obtained.
[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. FIG. 4 is a front view of a typical surface-mount type piezoelectric vibrator according to the prior art. FIG. 5 is a front view of a surface-mount type piezoelectric vibrator according to the present invention. FIG. FIG. 7 is a top view of a related surface-mounted piezoelectric vibrator. FIG. 7 is a side view of a surface-mounted piezoelectric vibrator according to the present invention. FIG. 8 is a thermoplastic covering a surface-mounted piezoelectric vibrator according to an embodiment of the present invention. FIG. 9 is a perspective view of a resin molded product. FIG. 9 is a front view of a surface mounting type piezoelectric vibrator according to another embodiment of the present invention in a manufacturing process. FIG. 10 is a surface mounting type piezoelectric vibrating embodiment of the present invention. FIG. 11 is a front view of a heating plate according to an embodiment of the present invention. Top view of a heating plate which is an embodiment of the 12 present invention EXPLANATION OF REFERENCE NUMERALS
DESCRIPTION OF SYMBOLS 1 Lead type cylindrical piezoelectric vibrator 2 Lead 3 Lead 4 Electrode 5 Electrode 6 Terminal 7 Terminal 8 Thermoplastic resin 9 Special jig 11 Lead type cylindrical piezoelectric vibrator 12 Lead 13 Lead 17 Thermoplastic resin 18 Plane of thermoplastic resin Part 19 Flat part of thermoplastic resin 20 Thermoplastic resin molded product 22 Lead 23 Lead 25 Solder 26 Substrate 30 Heating plate 31 Projection 32 Projection 33 Projection 34 Projection 35 Projection 36 Projection 37 Projection 38 Projection

Claims (3)

A surface-mounted piezoelectric vibrator characterized in that a thermoplastic resin having one or more flat surfaces is provided around a cylindrical portion of a lead-type cylindrical piezoelectric vibrator having two leads at one end. 2. The surface mount type piezoelectric vibrator according to claim 1, wherein the tip of the lead type cylindrical piezoelectric vibrator is exposed from the thermoplastic resin. At least a step of covering a cylindrical portion of a lead-type cylindrical piezoelectric vibrator having two leads at one end with a cylindrical thermoplastic resin, and heating the thermoplastic resin to form one or more flat portions. And a step of cutting and forming the lead with reference to the flat portion.

Images