JPH0758575A - Piezoelectric component use lead terminal - Google Patents

Abstract

PURPOSE:To improve a electric characteristic by arranging a sealing agent for a piezoelectric component to a gap between a folded part and a non-folded part of an electrode chip so as to part a natural resonance frequency of a lead terminal from a main frequency of the piezoelectric component. CONSTITUTION:A lead terminal 11 provided with an electrode chip 11a, an external connection section 11b, and projections 11c, 11d is cut from e.g. a metallic raw material and formed by folding processing. The electrode chip 11a is overlapped double through folding processing and made up of a non- folding part 111 and a folded part 112. Furthermore, a projection 11d is provided to the non-folding part 111 and a projection 11c is provided to a folded part 112 and a seal agent flowing prevention claw 113 is provided to a tip of the folded part 112. Then the external connection part 11b is connected to the non-folding part 111 of the electrode chip 11a and part of the sealing agent 31 flows to the gap between the non-folded part 111 and the folded part 112.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lead terminal which is a component of a piezoelectric component, and more particularly to a lead terminal for a piezoelectric component which has an electrode piece portion which is bent and is double overlapped.

[0002]

BACKGROUND OF THE INVENTION Conventionally, as a lead terminal used in a piezoelectric component, an electrode piece portion is bent and superposed in a double manner, and a projection is provided in each of a non-bent portion and a bent portion. Things are known. One problem has been pointed out in the piezoelectric component in which the bent double-sided protruding terminals, the piezoelectric resonator, and the like are stacked and housed in a substantially box-shaped case. That is, the natural resonance frequency of the double-sided protruding terminal and the main frequency of the piezoelectric component (for example, 455 kHz)
Are close to each other, so that the natural resonance frequency of the double-sided protruding terminal adversely affects the electrical characteristics of the piezoelectric component.

Therefore, an object of the present invention is to provide a lead terminal for a piezoelectric component that does not adversely affect the electrical characteristics of the piezoelectric component at the main frequency.

[0004]

In order to solve the above problems, a lead terminal for a piezoelectric component according to the present invention comprises:
(A) An electrode piece part that is bent and double-superposed.
A protrusion provided on a bent portion of the electrode piece portion and a protrusion provided on a non-folded portion, and an external connection portion connected to the electrode piece portion; The sealant for sealing the piezoelectric component is provided in the gap between the non-bent portions.

In the above structure, since the sealant for sealing the piezoelectric component is provided in the gap between the bent portion and the non-bent portion of the electrode piece portion, the natural resonance frequency of the lead terminal is deviated, and the piezoelectric component is displaced. Will move away from the main frequency.

[0006]

Embodiments of the lead terminal for a piezoelectric component according to the present invention will be described below with reference to the accompanying drawings. [First Embodiment, FIGS. 1 to 3] As shown in FIG. 1, the lead terminal 11 includes an electrode piece portion 11a, an external connection portion 11b, and a protrusion 1.
It is equipped with 1c and 11d. The lead terminal 11 is manufactured, for example, by cutting it from a metal material by a press cut method and then bending it. Electrode piece 1
Reference numeral 1a has a structure in which it is bent and doubled, and includes a non-bent portion 111 and a bent portion 112. The non-folded portion 111 is provided with a protrusion 11d, and the folded portion 112 is provided with a protrusion 11c. Further, a sealing sealant inflow preventing claw 113 is provided at the tip of the bent portion 112. The external connection portion 11b is connected to the non-bent portion 111 of the electrode piece portion 11a. As will be described later, a part 31a of the sealing agent 31 for sealing flows into the gap between the non-bent portion 111 and the folded portion 112.

In the lead terminal 11 having the above structure, the sealing material 31a for sealing is disposed in the gap between the non-bent portion 111 and the bent portion 112, so that the natural resonance frequency shifts and the main component of the piezoelectric component is displaced. It will move away from the frequency. Therefore, the piezoelectric component including the lead terminal 11 is
The electrical characteristics at the main frequency are improved. Next, the function and effect of the lead terminal 11 will be described by taking a ladder type filter using the lead terminal 11 as an output terminal as an example.

As shown in FIG. 2, the ladder type filter is
It is composed of a substantially box-shaped case 1, two piezoelectric resonators 5 and 6, an input terminal 10, a lead terminal 11, a ground terminal 12, and a spring terminal 20. The piezoelectric resonators 5 and 6 are well-known ones in which vibration electrodes are provided on the front and back surfaces, respectively, and vibrate in a spreading vibration mode. The case 1 has an opening 1a on the right side and is made of resin, ceramics or the like.

Lead terminal 11 functioning as an output terminal
The protrusion 11c is pressed against the lower surface of the piezoelectric resonator 6,
1d is in pressure contact with the upper surface of the piezoelectric resonator 5. Input terminal 1
Reference numeral 0 includes an electrode piece portion 10a, an external connection portion 10b, and a protrusion 10c, and the protrusion 10c is in pressure contact with the lower surface of the piezoelectric resonator 5. The ground terminal 12 includes the electrode piece portion 12a and the external connection portion 1
2b and a protrusion 12c are provided, and the protrusion 12c is in pressure contact with the upper surface of the piezoelectric resonator 6.

The above piezoelectric resonators 5 and 6 and terminals 10 to 1
2 is accommodated in the case 1. The spring terminal 20 is sandwiched between the case 1 and the terminal 10 so as to generate an appropriate pressure contact force between the piezoelectric resonators 5 and 6 and the terminals 10 to 12. Next, after setting the insulating paper 30 on the step portion of the opening 1a of the case 1,
The opening 1a of the case 1 is filled with a sealing sealant 31 such as a thermosetting resin.

A part 31 of the filled sealing agent 31
a flows into the gap between the non-bent portion 111 and the bent portion 112 through the gap between the hole 30a provided in the insulating paper 30 and the lead terminal 11, and the sealing agent inflow prevention claw 113 for sealing.
Prevents the sealing agent 31 for sealing from flowing into the outer surface of the electrode piece portion 11a. Next, the case 1 is heated with hot air or the like to cure the sealing sealant 31. In this way, the sealing agent 31a can be easily disposed in the gap between the non-bent portion 111 and the bent portion 112 of the lead terminal 11.

FIG. 3 is an electrical equivalent circuit diagram of the obtained ladder type filter. The piezoelectric resonator 5 connected in series between the input terminal 10 and the lead terminal 11 and the piezoelectric resonator 6 connected in parallel form a ladder structure. Since the sealing material 31a is disposed in the gap between the non-bent portion 111 and the bent portion 112 of the lead terminal 11, the natural resonance frequency of the lead terminal 11 becomes far from the main frequency of the ladder filter. . Therefore, it is possible to obtain a ladder type filter that is less affected by the terminal resonance frequency at the main frequency, as compared with the conventional ladder type filter having a lead terminal.

[Second Embodiment, FIG. 4] As shown in FIG.
The lead terminal 21 includes an electrode piece portion 21a, an external connection portion 21b, and protrusions 21c and 21d. The electrode piece portion 21a has a structure in which the electrode piece portion 21a is bent and superposed in a doubled manner, and includes an unfolded portion 121 and a folded portion 122. The non-bent portion 121 is provided with a protrusion 21d, and the bent portion 122 is provided with a protrusion 21c. External connection 2
1b is connected to the non-bent portion 121 of the electrode piece portion 21a.

Further, a thin groove 123 is provided extending from the external connection portion 21b to the non-bent portion 121. Groove 1
23 has one end branched into a plurality of branches, and the other end extends to a position where the non-bent portion 121 and the bent portion 122 overlap each other. A part of the sealing agent for sealing the piezoelectric component flows along the groove 123 by the capillary phenomenon, flows into the gap between the non-bent portion 121 and the bent portion 122, and is disposed.

The lead terminal 21 having the above structure has the same effect as the lead terminal 11 of the first embodiment. [Other Embodiments] The lead terminal for a piezoelectric component according to the present invention is not limited to the above embodiment, but can be variously modified within the scope of the gist thereof. In particular, this lead terminal may be used as an input terminal, a ground terminal, a relay terminal, or the like, or may be used for two or more terminals.

[0016]

As is apparent from the above description, according to the present invention, since the sealant for sealing the piezoelectric component is arranged in the gap between the bent portion and the non-folded portion of the electrode piece portion, The natural resonance frequency of the terminal will move away from the main frequency of the piezoelectric component. Therefore, the piezoelectric component including the lead terminal has improved electrical characteristics at the main frequency.

[Brief description of drawings]

FIG. 1 is a perspective view showing a first embodiment of a lead terminal for a piezoelectric component according to the present invention.

FIG. 2 is a partial cross-sectional view of a ladder type filter including the lead terminal for the piezoelectric component shown in FIG.

FIG. 3 is an electrical equivalent circuit diagram of the ladder filter shown in FIG.

FIG. 4 is a perspective view showing a second embodiment of the lead terminal for a piezoelectric component according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 ... Lead terminal 11a ... Electrode piece 31a ... Sealing agent 111 for sealing 111 ... Non-bending part 112 ... Bending part 21 ... Lead terminal 21a ... Electrode piece 121 ... Non-bending part 122 ... Bending part

Claims (1)

[Claims] 1. An electrode piece part that is bent and superposed in a double manner, a protrusion provided on a bent part of the electrode piece part and a protrusion provided on a non-bent part, and connected to the electrode piece part. A lead for a piezoelectric component, wherein a sealant for sealing a piezoelectric component is provided in a gap between the bent portion and the non-bent portion of the electrode piece portion. Terminal.