JPH0258412A - Manufacture of piezoelectric element and intermediate molded goods used for the manufacture - Google Patents

Abstract

PURPOSE:To evade the silver wear to spread while the component of an electrode is soldered by applying a soldering resist material beforehand to a pair of auxiliary terminals held by sandwiching a piezoelectric substrate. CONSTITUTION:At auxiliary terminals 11 and 12 provided continuously between a pair of lead terminals 9 and 10, a soldering resist material 13 with a poor soldering is applied. Consequently, in the process to stick the preliminary solder to the lead terminals 9 and 10, the solder is not stuck to the auxiliary terminals 11 and 12 and the preliminary solder is stuck to only the lead terminals 9 and 10. Thus, when by the heating, the solder is melted and taken out and the lead terminals 9 and 10 are connected to electrodes 5 and 6, the silver wear does not occur and the melted solder does not scatter regardless of the fact that tip parts 11a and 12a of the auxiliary terminals 11 and 12 to sandwich a piezoelectric substrate 2 are abutted to the oscillation electrodes 3 and 4 and the vicinity of a piezoelectric substrate 1.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for manufacturing a piezoelectric element and an intermediate molded product used in the manufacturing method. As shown in FIG. 1, the piezoelectric resonator has vibrating electrodes 3.4 made of silver or the like facing approximately the center of the front and back surfaces of the piezoelectric substrate 2.
Lead terminals 9 and 10 are connected by soldering to extraction electrodes 5 and 6 extending from the vibrating electrodes 3 and 4 to the edge side of the piezoelectric substrate 2. Although FIG. 1 shows a piezoelectric element manufactured by the method according to the present invention, it is structurally the same as a conventional one, and will be cited here for explanation of the conventional example.

In manufacturing this type of piezoelectric element 1, a hoop material is first punched out, and a pair of lead terminals and a pair of auxiliary terminals connected between the lead terminals are formed in a comb-teeth shape on the tie bar. Note that this auxiliary terminal provides stability when the lead terminal is taken out and soldered to the electrodes 5 and 6, and is essential for automation. Next, the tips of the terminal group consisting of lead terminals and auxiliary terminals are immersed in molten preliminary solder 2, and a pre-fit half 111 is attached to each tip. Next, the lead terminals are brought into contact with each of the lead-out electrodes 5.about.6 of the piezoelectric substrate 2, and the auxiliary terminals are brought into contact with and held against the front and back surfaces of the piezoelectric substrate 20, and the piezoelectric substrate 2 is held by each tip. . Then, in this state, it is heated by blowing hot air, passing it through a high-temperature furnace, etc., and the lead terminals are connected to the extraction electrodes 5.6 of the piezoelectric substrate 2. Finally, cut out the lead terminals and auxiliary terminals from the tie bar, and
A piezoelectric element 1 with only lead terminals 9 and 10 remaining is obtained.

Problems to be Solved by the Invention However, in the conventional manufacturing method, preliminary solder is attached to the auxiliary terminals that clamp the piezoelectric substrate 2, and furthermore, the preliminary solder is located between the lead terminals and comes into contact with the vibrating electrode 3.4 or its vicinity. Therefore, during the soldering process of the lead terminals, there is a problem in that the F-rings in the vibrating electrodes 3 and 4 diffuse into the solder of the auxiliary terminals, resulting in so-called silver cracks.

Also, when soldering by blowing hot air,
There was also a problem in that the solder adhering to the auxiliary terminals was scattered, albeit slightly, by melting and adhering to the vibrating electrodes 3 and 4. Due to these silver cracks and adhesion of foreign matter, the piezoelectric element has problems in that desired vibration characteristics cannot be obtained and reliability is also poor. Moreover, the yield was poor and the production efficiency was low. Furthermore, in order to avoid the problem of solder flying, attempts have been made to use a high-temperature furnace instead of the hot-air blowing method, but the high-temperature furnace requires a longer working time than the hot-air blowing method. Therefore, there remained problems such as a limit to the improvement of work efficiency.

The present invention was developed in view of the above-mentioned problems, and its object is to provide excellent vibration characteristics by simply applying a simple treatment to the auxiliary terminal that holds the 1E electric board in the manufacturing process of the piezoelectric element. Another object of the present invention is to obtain a piezoelectric element with high reliability, improve workability, and increase production efficiency.

In order to achieve the problem 1-, the method for manufacturing a piezoelectric element according to the present invention includes: In a method for manufacturing a piezoelectric element in which lead terminals are connected to electrodes, (b) a pair of lead terminals are formed in a comb-teeth shape in a hoop material, and a pair of auxiliary terminals are arranged in series between the lead terminals. (c) applying a solder resist material to the auxiliary terminal in advance; (d) attaching the tips of the lead terminal and the auxiliary terminal to a preliminary half [H
(e) sandwiching the piezoelectric substrate between the lead terminal and the auxiliary terminal and bringing the lead terminal into contact with the lead terminal 17; (g) cutting the lead terminal and the auxiliary terminal from the quiver; and (g) cutting the lead terminal and the auxiliary terminal from the quiver.

Effects In the present invention, since the auxiliary terminal connected between the pair of lead terminals is coated with a solder resist material that has poor soldering properties, it is difficult to attach the preliminary half FD to the lead terminal in the step of attaching the preliminary half FD to the lead terminal. , the half FD does not adhere to the auxiliary terminal, and the preliminary solder adheres only to the lead terminal. Therefore, when the solder is melted by heating and the lead terminal is connected to the extraction electrode, the tip of the auxiliary terminal that clamps the piezoelectric substrate comes into contact with the vibrating electrode of the piezoelectric substrate or its vicinity.
゛No silver holes or molten solder will be scattered. Heating for soldering may be done using a high-temperature furnace, but if a hot air blowing method is adopted, it will be advantageous in terms of productivity.

Hereinafter, embodiments of the present invention will be explained based on the attached drawings.
Figure 1 shows the pressure and gravity f obtained by the manufacturing method according to the present invention.
-1 is shown, , piezoelectric J, (handling 2 and its front and back surfaces 2a.

2b, vibrating electrodes 3, 4 provided on the vibrating electrodes 3, 4, lead-out electrodes 5, 6 extending from the vibrating electrodes 3, 4;
6 and lead terminals 9 and 10 which are connected to each other make up 114 terminals. The piezoelectric circumferential plate 2 is a rectangular shaped plate, vibrates approximately at the center, and generates energy-trapped thickness longitudinal vibration at the opposing portions of the poles 3 and 4.

Next, a method for manufacturing the piezoelectric element 1 having the above configuration will be described.

Masataka: As shown in FIG. 2, a tie bar 8 for forming a feed 68a in the hoop material 7 and a group of comb-shaped terminals 9 to 12 connected to the tie bar 8 are formed by punching. These terminal groups 9 to 12 are located at the lead terminal 1 of the piezoelectric element 1, and the lead terminals 9 and 10 are connected at equal intervals of 60, and the lead terminals 9 and 10 are connected at equal intervals between the pair of lead terminals 9 and 10. It consists of a pair of auxiliary terminals 11 and 12 provided. Among the terminal groups 9 to 12, the node terminal 10 and the auxiliary terminal 11
means that the tip portions 10a and 11a are bent closer to each other, and the distance in the thickness direction between the tip portions 9g and 12a of the lead terminal 9 and the auxiliary terminal 12 and the tip portions 10a and lla of the lead terminal 10 and the auxiliary terminal 11 is, It is formed to have the same thickness as the piezoelectric substrate 2.

Next, as shown in FIG. 3, a solder resist material 13 is applied to the tips 11a, 12a of the auxiliary terminals 11.12.

As the solder resist material 13, a solder resist ink is used which has poor soldering properties and has the property of emitting solder at high temperatures. Specifically, a base plate is placed on a flat iron 14 and applied sequentially only to the tips 11a and 12a of the auxiliary terminals 11.12.

Note that this coating work employs a method in which the movement of the tie bar 8 and the forward and backward movement of the edge 14 are linked.

That is, while the terminal group of the tie bar 8 is tact-feeded in the horizontal direction, the iron 14 is moved up and down, and the pair of auxiliary ends "i" 41
．． 12 is positioned directly above the soldering iron 14, simultaneously preventing the soldering iron 14 from rising, and inserting the auxiliary terminal 11.1 into the solder resist material 13.
2. Embed the tip portions 11a and 12a of '2. Then, at the same time as the tie bar 8 is transferred to the next process, the iron L4 is lowered. This allows the solder resist material 13 to be applied around the tips 11a and 12a without deforming the auxiliary terminals 11 and 12! 1 can be added to the top.

As shown in FIG. 4, the terminal groups 9 to 12 are immersed in the molten solder 15 in the solder dip bath 16 in order to prevent the preliminary half [1iJ] from adhering to the lead terminals 9 and 1°. At this time, the tips 9a to 12a of each terminal group 9 to 12 come into contact with the solder 15, but since the solder resist material 13 is applied to the auxiliary terminals 11 and 12, it repels the solder 15 and prevents its adhesion. be done. Therefore, the tips 98.1 of lead terminals 9, 1o
Solder 15 is attached only to 0a.

Thereafter, as shown in FIG. 5, the lead terminals 9 and 1° are connected to the lead-out electrodes 5 and 6 of the piezoelectric substrate 2 by soldering.

First, the piezoelectric substrate 2 is inserted into the terminal group 9 to 12, the lead terminal 9 is taken out and the lead terminal 10 is taken out to the electrode 5, and the lead terminal 10 is taken out to the terminal group TL.
The electrodes are brought into contact with each other, and the auxiliary terminals 11 and 12 are brought into contact with the front surface 2a and the back surface 2b of the piezoelectric substrate 2, respectively. With this, the piezoelectric substrate 2 is attached to each terminal, 9 to 1.
It is held in a state where it is held between two.

Next, by blowing hot air, the lead terminal 9.10
The solder 15 attached to the is heated. melting of solder 15;
Lead terminals 9, 10 and extraction electrodes 5, 6 are removed by re-hardening.
The connection is floating. At this time, since no solder is attached to the tips 11a and 12a of the auxiliary terminals 11 and 12,
For example, even if the vibrating electrodes 3, 4 and the auxiliary terminals 11.12 are in contact with each other or in close proximity to each other, the vibrating electrodes 3.4 will not suffer from silver dents. Further, there is no scattering of solder from the auxiliary terminals 11 and 12.

Finally, the lead terminals 9, 10 and the auxiliary terminals 11.12 are cut along the line CC in FIG. 5 by dicing, and the tie bars 8 and the auxiliary terminals 11.12 are removed.

j3. The manufacturing method according to the present invention and its intermediate molded product are as follows:
The present invention is not limited to the embodiments described above, and various modifications can be made within the scope of the gist thereof.

As detailed above, according to the present invention, a solder resist material is applied in advance to a pair of auxiliary terminals that are connected between a pair of lead terminals and hold the piezoelectric substrate between them. When applying preliminary solder to the terminals, the solder does not adhere to the auxiliary terminals, but only to the lead terminals. For this reason, even if the vibrating electrode of the piezoelectric substrate or the auxiliary terminal comes into contact with the vibrating electrode, when soldering is connected by heating, the constituent material of the electrode will diffuse into the solder as in the past. Avoided. Furthermore, since no solder is attached to the auxiliary terminals as described above, there is no problem of solder flying when soldering is performed by blowing hot air. Therefore, a piezoelectric element with good vibration characteristics and high reliability can be manufactured with a high yield.

In addition, the process of applying solder resist material is extremely simple and can be automated, and hot air blowing can be used during the soldering process, making it possible to significantly shorten work time and significantly improve production efficiency. It has the effect of

[Brief explanation of the drawing]

FIG. 1 is a perspective view of a piezoelectric element manufactured by the manufacturing method according to the present invention, and FIGS. 2 to 5 are process explanatory diagrams showing one embodiment of the piezoelectric element manufacturing method. DESCRIPTION OF SYMBOLS 1... Piezoelectric element, 2... Piezoelectric substrate, 3, 4... Vibration electrode, 5, 6... Extraction electrode, 7... Hoop material,
9, 10... Lead terminal, 11.12... Auxiliary terminal, 13... Solder resist material. Patent applicant Murata Manufacturing Co., Ltd.

Claims (2)

[Claims] 1. A method for manufacturing a piezoelectric element in which a lead terminal is connected to an extraction electrode extending from a vibrating electrode provided opposite to the front and back surfaces of a piezoelectric substrate, which includes forming a pair of lead terminals in a comb-like shape on a hoop material, and , a step of arranging a pair of auxiliary terminals in series between the lead terminals; a step of applying a solder resist material to the auxiliary terminals in advance; a step of immersing the tips of the lead terminals and the auxiliary terminals in preliminary solder; sandwiching the piezoelectric substrate between a lead terminal and an auxiliary terminal, and bringing the lead terminal into contact with the extraction electrode; and connecting the lead terminal and the extraction electrode by heating the solder attached to the lead terminal. A method for manufacturing a piezoelectric element, comprising: a step of separating the lead terminal and the auxiliary terminal from the tie bar. 2. 1. An intermediate molded product of a piezoelectric element, characterized in that a plurality of lead terminals and an auxiliary terminal are arranged in series on a hoop material, and the auxiliary terminal is coated with a solder resist material.