JPH057122A - Electronic parts - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide an electronic component having a high yield, a high mechanical strength, and a simple structure. [Configuration] A piezoelectric filter 30 as an electronic component includes a plate-shaped piezoelectric filter element 10. The main surface of the element 10 is supported on one main surface of the metal plate 21 having substantially the same size and shape. In this case, the metal plate 21 is connected to the drawer portion of the element 10. Further, the lead terminal 22 is formed extending from the metal plate 21. Furthermore, the tips of the other lead terminals 24a and 24b are connected to the other lead-out portions 18a and 18b of the element 10. These lead terminals 24a and 24
Notches 25a and 25b are formed in the vicinity of the tips of b, and the tips thereof are notches 25a and 25b.
Can be bent with the fulcrum as a fulcrum.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to electronic parts, and more particularly to electronic parts having plate-shaped elements such as ceramic resonators, ceramic filters or integrated circuit elements.

[0002]

7 (A) and 7 (B) show a filter element as a background of the present invention, FIG. 7 (A) is a front view thereof, and FIG. 7 (B) is a rear view thereof. is there. The filter element 10 shown in FIGS. 7 (A) and 7 (B) is an energy trapping type piezoelectric filter utilizing a thickness shear vibration mode (share mode). Since the present invention is particularly suitable for such a piezoelectric filter, the filter element will be described here to the extent necessary for understanding the present invention.

The element 10 includes a strip-shaped piezoelectric substrate 12 made of piezoelectric ceramic, for example.
The slit 13 is formed on the upper end 2 from the upper end to the almost center thereof in the longitudinal direction. Further, a pair of vibrating electrodes 14a and 14c1 and 14b and 14c2 are formed on both left and right sides divided by the slit 13 on the one main surface of the piezoelectric substrate 12, respectively. Electrode 14c of the left and right vibrating electrodes
1 and 14c2 are commonly connected. On the other main surface of the piezoelectric substrate 12, the common electrodes 16a and 1 are provided so as to face the respective vibrating electrodes 14a and 14c1 and 14b and 14c2.
6b are formed.

A lead portion 18a extending from the vibrating electrode 14a to the upper end of the piezoelectric substrate 12 is formed on one main surface of the piezoelectric substrate 12, and the vibrating electrode 14b and the piezoelectric substrate 12 are formed.
To the upper end of the pull-out part 18b. Further, a lead-out portion 20 that is commonly connected to the common electrodes 16 a and 16 b and extends to the lower end of the piezoelectric substrate 12 is formed on the other main surface of the piezoelectric substrate 12. These electrodes and lead portions are formed by vapor deposition or sputtering of silver, nickel, or the like.

Lead terminals are connected to such a filter element 10. That is, as shown in FIG. 8, the lead terminal 22 is the lead-out portion 20, the lead terminal 24a is the lead-out portion 18a, and the lead terminal 24b is the lead-out portion 18b.
Respectively, for example by soldering.

Further, as shown in FIG.
The filter element 10 to which 2, 24a and 24b are connected is covered with an elastic material 26 such as silicon rubber, and further covered with an exterior material 28 such as resin, and has a circuit configuration as shown in FIG. Formed as 30.

In this piezoelectric filter 30, since the filter element 10 is in the form of floating in the elastic material 26 not only during manufacturing but also after completion, the element 10 may be destroyed by an external impact. there were. In particular, it is remarkable when the slit 13 is formed in the center of the piezoelectric substrate 12 of the element 10.

[0008]

Such a piezoelectric substrate 1
In order to prevent 2 cracks or cracks,
Japanese Patent No. 85723 proposes to use a reinforcing substrate as shown in FIG. That is, on the surface of the reinforcing substrate 40 made of an insulating material, the lead terminals 2 of FIG.
Conductor patterns 42, 44a and 44b corresponding to the respective tip portions of 2, 24a and 24b are formed. The filter element 10 is provided on the surface of the reinforcing substrate 40.
Is placed and one end of each of the conductor patterns 42, 44a and 44b is soldered to the lead portions 20, 18a and 18b of the element 10, for example. The lead terminals 22, 24a and 24 are provided on the other ends of the conductor patterns 42, 44a and 44b, respectively.
b is soldered, for example.

In this conventional technique, the mechanical strength is increased to the extent that the element is not cracked, but it is necessary to prepare a reinforcing substrate having a predetermined conductor pattern as a separate component, and the number of components is increased. In addition, the number of soldering points increases and the manufacturing process becomes complicated.
As a result, the cost becomes high. Further, since it is necessary to form a conductor pattern on the reinforcing substrate, the reinforcing substrate cannot be made smaller than the element, which causes a problem in downsizing the piezoelectric filter.

Further, Japanese Patent Application Laid-Open No. 56-131219 discloses an energy confinement type piezoelectric filter. In this piezoelectric filter, a thin metal plate formed by integrally forming a recess corresponding to the working electrode provided on the piezoelectric ceramic plate and a lead leg corresponding to the leg electrode connected to the working electrode is bonded to the piezoelectric ceramic plate. Cover the actuating electrode with a gap, and electrically connect the lead leg to the leg electrode, and insulate the thin metal plate excluding a part of the projecting part of the lead leg from the piezoelectric ceramic plate with resin or the like. It is covered with layers. In this piezoelectric filter, since the thin metal plate is bonded to the piezoelectric ceramic plate, the piezoelectric ceramic plate is reinforced. However, in this piezoelectric filter, the manufacturing process is complicated because the recess must be formed at a predetermined position of the thin metal plate and the structure is complicated.

Further, Japanese Utility Model Laid-Open No. 59-108329 discloses an energy trap type piezoelectric vibrating component. This piezoelectric vibrating component comprises a piezoelectric substrate, and electrodes having electrodes facing each other with the piezoelectric substrates interposed therebetween on both main surfaces of the piezoelectric substrate. In at least one of the main surfaces, a vibration space around the electrodes is provided. Therefore, a reinforcing plate is provided to reinforce the mechanical strength of the piezoelectric substrate. In this piezoelectric vibration component, the mechanical strength of the piezoelectric substrate is reinforced by the reinforcing plate. However, since this piezoelectric vibrating component does not have a lead terminal extending to the outside of the element, it cannot be easily connected to other components, and if a lead terminal is provided to facilitate such connection, the structure is Becomes complicated and the manufacturing process becomes complicated.

Therefore, the inventor of the present invention has devised an electronic component such as a piezoelectric filter having a simple structure and improved mechanical strength. 12 is a front view showing an example of such a piezoelectric filter, FIG. 13 is a front view showing a hoop material used in the piezoelectric filter shown in FIG. 12, and FIG. 14 is a side view of the piezoelectric filter shown in FIG. Is. In this piezoelectric filter, the piezoelectric filter element 10 shown in FIGS. 7A and 7B is used.

Referring to FIG. 13, metal plate 21 is made of metal such as nickel silver, brass, or 42 nickel (nickel-iron alloy containing 42% nickel), and has substantially the same shape as element 10. Formed to the same size. Then, on the metal plate 21, as shown in FIG. 13, at a position corresponding to the pull-out portion 20 of the element 10,
The through hole 21a is formed. In addition, this through hole 21a
Can visually confirm the positional deviation between the metal plate 21 and the element 10 through it.
Although there is an advantage that connection fixing such as soldering with the metal plate 21 can be easily performed, it may not be formed in some cases.

A lead terminal 22 is formed extending downward from the center of the lower end of the metal plate 21. The lead terminal 22 is formed so as to extend upward from the frame 25. Further, the lead terminals 24 a and 24 b are formed on both sides of the lead terminal 22 so as to extend upward from the frame 25 in parallel at predetermined intervals. Therefore, the metal plate 21 and the lead terminals 22, 2
4a and 24b extend from the frame 25 and are integrally formed, and are configured as a so-called hoop material. Further, the free ends of the lead terminals 24a and 24b are bent inwardly to form bent portions 24a1 and 24b1. It is formed. The bent portions 24a1 and 24b1 are formed by the metal plate 2
Element 1 shown in FIGS. 7 (A) and 7 (B) on top of FIG.
When 0 is placed, it corresponds to the drawer portions 18a and 18b, respectively.

Referring to FIGS. 12 and 14, the metal plate 2
The surface of the element 1 has an element 10 (FIG. 7A and FIG.
(See (B)) is placed. In this case, the element 10
Is sandwiched between the metal plate 21 and the bent portions 24a1 and 24b1 and is temporarily fixed. That is, the metal plate 2
1, the element 10 is wholly supported, and the bent portions 24a1 and 24a are formed on the main surface of the upper end portion of the element 10.
b1 is placed. Since each of the lead terminals 24a and 24b extends integrally from the frame 25, it has a spring property. Due to the springiness of the lead terminals 24a and 24b, the element 10 can be sandwiched between it and the metal plate 21.

Next, the lead terminals 22, 24a and 2
4b and the element 10 are connected. First, as shown in FIG. 14, the lead-out portion 20 of the element 10 is electrically connected and mechanically fixed to the peripheral portion of the metal plate 21 defining the through hole 21a by, for example, soldering. Such a metal plate 21, that is, a lead terminal 22
Alternatively, the connection and fixation of the element 10 and the lead-out portion 20 of the element 10 may be performed by, for example, a conductive adhesive or the like. The lead-out portions 18a and 18b of the element 10 are
The bent portions 24 of the lead terminals 24a and 24b, respectively
It is electrically connected and mechanically fixed to a1 and 24b1 by, for example, soldering or a conductive adhesive.

After that, the lead terminals 22, 24a and 2
In the state in which 4b is connected, the periphery of the element 10 is covered with an elastic material (not shown) such as silicon rubber, and a surrounding material (not shown) such as resin is further formed around the element.

Finally, the lead terminals 22, 24a and 2
4b is separated from the frame 25 to complete the piezoelectric filter 30 as shown in FIG.

Further, the piezoelectric filter shown in FIG.
Compared with the conventional piezoelectric filter shown in FIG. 11 and FIG. 11, the spurious characteristic in the attenuation region is improved.

That is, FIG. 15 is a graph showing the frequency characteristic of the piezoelectric filter. The solid line shows the characteristic of the piezoelectric filter 30 shown in FIG. 12, and the dotted line shows the characteristic of the conventional example.

As is apparent from FIG. 15, the piezoelectric filter 30 shown in FIG. 12 has a spurious characteristic of about 5d in the attenuation region as compared with the conventional piezoelectric filters shown in FIGS. 8 and 11.
B has been improved. This is because the metal plate 21 worked as a shield plate. That is, in the piezoelectric filter 30 shown in FIG. 12, the metal plate 21 exists between the input and the output of the circuit configuration shown in FIG.
The grounding of the capacitor acts as a shield plate between the input and output, improving the isolation between the input and output and improving the spurious characteristics as a filter.

Further, the metal plate 21 and the lead terminals 22 and 24
When 42 nickel is used as the material of a and 24b, the temperature characteristics of the piezoelectric filter 30 can be improved as compared with the case of using other general materials such as nickel silver and brass. This is because 42 nickel has almost the same linear expansion coefficient and Young's modulus as the piezoelectric substrate 12, as can be seen from Table 1. If the coefficient of linear expansion of the substrate 12, that is, the element 10 and the metal plate 21 is very different, not only the center frequency greatly changes due to temperature change, but also the stress increases due to heat shock, and the piezoelectric substrate 12 and the metal plate 21 increase. 21 may lead to breakage at the joints with the lead terminals 22 and 24a and 24b or cracks to the piezoelectric substrate 12, but in the case of 42 nickel, such changes in electrical characteristics and deterioration of mechanical strength may occur. Is effectively prevented.

[0023]

[Table 1]

According to experiments by the inventors, for example, in the case of nickel silver, the temperature characteristic of the center frequency of the filter is N30pp.
In contrast to m / ° C, the temperature characteristic of the center frequency when using 42 nickel was as low as N10ppm / ° C.

However, the piezoelectric filter 30 shown in FIG.
Then, by bending the free ends of the lead terminals 24a and 24b inward with respect to each other, the bent portions 24a1 and 2a
4b1 is formed, the bent portions 24a1 and 24b are formed.
1 has a large variation in shape and size, and the product yield is poor.

Therefore, a main object of the present invention is to provide an electronic component having a good yield, a high mechanical strength and a simple structure.

[0027]

DISCLOSURE OF THE INVENTION According to the present invention, a plate-shaped element and an element having substantially the same shape and size as that of the element, the main surface of the element being supported on one main surface thereof, are provided. A metal plate connected to the lead-out portion on the main surface, a lead terminal extending from this metal plate, and its tip connected to another lead-out portion on another main surface of the element and parallel to the lead terminal And another lead terminal extending to the, a notch is formed in the vicinity of the tip of the other lead terminal, and the tip of the other lead terminal is bent by using the notch as a fulcrum.

[0028]

The plate-shaped element is wholly supported on one main surface of the metal plate. Therefore, the lead terminal extending from this metal plate is connected to the lead-out portion on the main surface of the element. On the other hand, the tip of another lead terminal is bent with the notch as a fulcrum. Then, the tips of the other lead terminals are connected to the other lead portions on the other main surface of the element.
In this way, elements such as resistors, capacitors, filters or integrated circuits are connected between the lead terminals.

[0029]

According to the present invention, since the tip of the lead terminal is bent around the notch formed near the tip as a fulcrum, it is possible to reduce variations in the shape and size of the tip of the lead terminal. This improves the product yield.

Further, according to the present invention, since the element is wholly supported by the metal plate, the shock resistance is improved as compared with the conventional element in which the element is simply covered with the elastic material, and the element is improved. It is possible to effectively prevent the cracks and breakages. Moreover, since the metal plate is integrated with the lead terminal, the structure is simpler than that of the conventional one using the auxiliary substrate. That is, in the conventional device shown in FIG. 11, the reinforcing substrate and the lead terminal are separate, so that the number of parts and the process are complicated as compared with the conventional device shown in FIG. On the other hand, in the present invention, since the reinforcing metal plate is integrated with the lead terminals, it has mechanical strength equal to or higher than that using the reinforcing substrate, and there is no need to prepare a separate component. ,further,
There is no increase in man-hours such as soldering. Further, since the metal plate and the lead terminal can be simultaneously formed by, for example, press working, the process is further simplified.

Further, according to the present invention, the metal plate may act effectively as a shield plate. That is, for example, in an electronic component having a piezoelectric filter element as shown in FIGS. 7A and 7B, the input side and the output side of the filter are directly coupled via the stray capacitance, and therefore the attenuation range is reduced. The spurious characteristics were poor. However, if the metal plate of the present invention is used to ground it, there is the same effect as if a shield plate were interposed between the input and output, and therefore, according to the present invention, the isolation between the input and output is improved. When the present invention is applied to the piezoelectric filter element shown in FIGS. 7 (A) and 7 (B) as an example, the spurious characteristic in the attenuation region is improved by, for example, 5 dB as compared with the conventional one.

Further, according to the present invention, holding of the element in the manufacturing process is simplified. That is, in the conventional structure shown in FIG. 8, the element cannot be sandwiched between the lead terminals, the lead terminal cannot be temporarily fixed and held before soldering, and in the conventional structure shown in FIG. It was difficult to hold the reinforcing substrate integrally. On the other hand, according to the present invention, since the element is entirely supported on the metal plate, the element is sandwiched and temporarily fixed (temporary holding) by the metal plate and another lead terminal.
This is very convenient, especially when electronic parts are produced using an automatic assembling apparatus.

The above-mentioned objects, other objects, features and advantages of the present invention will become more apparent from the following detailed description of the embodiments with reference to the drawings.

[0034]

1 is a front view showing an embodiment of the present invention. 2 (A) to 2 (D) show the hoop material used in the embodiment shown in FIG. 1, FIG. 2 (A) is a front view before forming the bent portion, and FIG. 2 (B) is the same. 2 is a side view, FIG.
FIG. 2C is a front view of a main part before forming a bent portion, and FIG.
FIG. 4 is a front view of a main part after forming a bent part.

In this embodiment, FIG. 7A and FIG.
Although the piezoelectric filter element 10 shown in (B) is used, the present invention can be applied to an element using another piezoelectric ceramic such as a ceramic resonator, a single crystal piezoelectric material such as quartz or an integrated circuit other than the piezoelectric material. It should be pointed out in advance that it can be applied to the electronic components of.

The metal plate 21 of this embodiment is particularly shown in FIG.
As shown in (B), the central portion, that is, the portion facing the common electrode (not shown) of the piezoelectric element 10 is curved. The curvature of the metal plate 21 is particularly shown in FIG.
(B) As shown by arrow B, it is formed relatively large. By thus forming the curvature in the metal plate 21, when the element 10 is mounted on the metal plate 21, the common electrodes 16a and 16b of the metal plate 21 and the element 10 are attached.
A large gap is formed between and. This gap helps prevent solder from flowing and adhering to the common electrodes 16a and 16b due to a capillary phenomenon between the element 10 and the metal plate 21. Thereby, it is possible to effectively prevent damping of vibration of the element 10 that occurs when solder is attached to the common electrodes 16a and 16b. Further, since the gap is formed large, the cleaning efficiency of the flux is improved, and as a result, the risk of corrosion of the vibrating electrode and the extraction electrode formed on the metal plate 21 and the element 10 due to the residual flux can be reduced.

Further, as shown in FIGS. 2A and 2C, notches 25a and 25b are formed inside the lead terminals 24a and 24b in the vicinity of the tips thereof, respectively. Then, with the notches 25a and 25b as fulcrums, a force is applied to their tip portions in the direction indicated by the arrow A in FIG. By doing so, the bent portions 24a1 and 24b1 are formed as shown in FIG.

Thus, the lead terminals 24a and 24
If notches 25a and 25b are formed at predetermined positions of b and the bent portions 24a1 and 24b1 are formed by using the notches 25a and 25b, variations in the shapes and dimensions of the bent portions 24a1 and 24b1 can be reduced. Therefore, the yield of products can be improved.

In this embodiment, like the piezoelectric filter shown in FIG. 12, the lead terminals 22, 24a and 24 are also provided.
After b is connected to the element 10, the periphery of the element 10 is covered with an elastic material (not shown), and an exterior material (not shown) is further formed around it, and finally, the frame 25
Is separated.

FIG. 3 is a perspective view showing a modification of the metal plate. In this example, the solder resistant film 32 is formed on the tip of the surface of the metal plate 21. The solder resistant film 32 is formed, for example, by applying a solder resistant resin such as solder resist ink. Solder resistant film 32
Otherwise, when the lead terminals 24a and 24b are soldered to the lead-out portions 18a and 18b, the lead-out portion 18
A short circuit due to a solder bridge may occur between a and 18b and the tip portion of the metal plate 21. If the solder resistant film 32 is formed, such a short circuit due to the solder bridge can be prevented, and the product yield can be improved. Therefore, when the solder resistant film 32 is formed, the lead terminals 24a and 24b and the lead portions 18a and 18b can be soldered by dipping, which can be expected to improve mass productivity.

4 (A) and 4 (B) show a modified example of the element, and FIG. 4 (A) is a front view thereof.
(B) is a rear view thereof. In this example, in particular FIG.
As is clear from (B), the solder-resistant film 34 is formed on and around the common electrodes 16a and 16b of the element 10.
Is formed. The solder resistant film 34 may also be a solder resist ink or the like. Thus, the solder resistant film 3
If No. 4 is not formed, solder will adhere to the common electrodes 16a and 16b in that portion, and the vibration will be damped. However, since the solder-resistant film 34 prevents the solder from adhering to the portions of the common electrodes 16a and 16b, it is possible to effectively prevent the vibration damping as described above. Therefore, the solder resistant film 34 is preferably the common electrodes 16a and 16b.
Is formed to have a length substantially equal to the width of the above and longer than the length in the vertical direction. The vibration frequency of the element 10 can be adjusted by changing the thickness and size of the solder resistant film 34.

Further, as shown in FIG. 4B, other solder resistant films 34a and 34b may be formed. The solder resistant film 34a is formed between the common electrodes 16a and 16b and the lead portion 20, and prevents the solder from flowing from the lead portion 20 and attaching to the common electrodes 16a and 16b. The solder-resistant film 34b is formed on the upper end portion of the back surface of the element 10, whereby the element 10 is formed.
It is possible to prevent the solder from flowing from the lead-out portions 18a and 18b to adhere to the common electrodes 16a and 16b.

The solder resistant films 34a and 3
Forming 4b also has an advantage that the element 10 can be prevented from tilting when the elements 10 are stacked and cut.

5 (A) and 5 (B) show another embodiment of the present invention, FIG. 5 (A) is a front view thereof, and FIG. 5 (B) is a side view thereof. This embodiment includes a reinforcing member 36 made of resin or adhesive, for example. The reinforcing member 36 is formed so as to cover the upper end portion of the piezoelectric substrate 12 of the element 10 and the bent portions 24a1 and 24b1 of the lead terminals 24a and 24b. Reinforcement member 36
Are lead terminals 24a and 24a when an external force is applied.
Prevent one of b from moving alone. That is, if there is no reinforcing member 36, the lead terminal 24a or 24b
However, if the reinforcing member 36 deforms both terminals 24a and 24b in the same manner, the element 10 may be destroyed. It can be effectively prevented. This can improve the reliability of the electronic component.

FIG. 6 is a perspective view showing a modification of the embodiment shown in FIGS. 5 (A) and 5 (B). In this example, FIG.
A reinforcing cap 38 is used in place of the reinforcing member 36 shown in FIGS. The reinforcing cap 38 is formed of, for example, a synthetic resin in a shape that covers the tip portion of the piezoelectric filter 30, and is fixed to the tip of the piezoelectric filter 30 with an adhesive, for example. In this way, the reinforcing cap 38 also prevents the element 10 from being broken and the reliability of the electronic component can be improved, as in the previous embodiment.

[Brief description of drawings]

FIG. 1 is a front view showing an embodiment of the present invention.

FIG. 2 shows a hoop member used in the embodiment shown in FIG. 1, and FIG. 2 (A) is a front view before forming a bent portion.
FIG. 2B is a side view thereof, FIG. 2C is a front view of an essential part before forming the bent part, and FIG. 2D is a front view of the essential part after forming the bent part.

FIG. 3 is a perspective view showing a modified example of a metal plate.

FIG. 4 shows a modified example of an element, FIG. 4 (A) is a front view thereof, and FIG. 4 (B) is a rear view thereof.

5 shows another embodiment of the present invention, FIG. 5 (A) is a front view thereof, and FIG. 5 (B) is a side view thereof.

FIG. 6 is a perspective view showing a modified example of the embodiment shown in FIGS. 5 (A) and 5 (B).

FIG. 7 shows an example of a piezoelectric filter element which is the background of the present invention and can be used in the present invention, and FIG.
Is a front view thereof, and FIG. 7B is a rear view thereof.

FIG. 8 is a front view in which lead terminals are attached to the elements shown in FIGS. 7A and 7B.

FIG. 9 is a cross-sectional view showing an example of a conventional piezoelectric filter.

10 is a circuit diagram of the piezoelectric filter shown in FIG.

FIG. 11 is a front view showing another example of a conventional piezoelectric filter.

FIG. 12 is a front view showing an example of a piezoelectric filter which is the background of the present invention.

13 is a front view showing a hoop material used in the piezoelectric filter shown in FIG.

FIG. 14 is a side view of the piezoelectric filter shown in FIG.

FIG. 15 is a graph showing frequency characteristics, where the solid line is shown in FIG.
2 shows the characteristics of the piezoelectric filter, and the dotted line shows the characteristics of the conventional example.

[Explanation of symbols]

 10 Piezoelectric Filter Element 12 Piezoelectric Substrate 14a, 14b, 14c1, 14c2 Vibrating Electrodes 16a, 16b Common Electrodes 18a, 18b, 20 Leading Part 21 Metal Plates 22, 24a, 24b Lead Terminals 24a1, 24b1 Bending Part 25a, 25b Notch Part 30 Piezoelectric filter

Claims (1)

Claim: What is claimed is: 1. A plate-shaped element, which is formed to have substantially the same shape and size as the element, the main surface of the element being supported on one main surface thereof, and the main surface of the element. A metal plate connected to the drawn-out portion on the surface, a lead terminal extending from the metal plate, and a tip connected to another drawn-out portion on the other main surface of the element, and parallel to the lead terminal. An electronic component that includes another lead terminal that extends in the form of a cutout, the notch being formed in the vicinity of the tip of the other lead terminal, and the tip of the other lead terminal being bent around the notch as a fulcrum.