JPH0711030U - Ceramic filter - Google Patents

Abstract

(57) [Abstract] [Structure] L-shaped frame 11 with lead 12 and connecting piece 13
An input terminal 10 integrally formed with the lead terminal 22, an output terminal 20 integrally formed with a lead portion 22 and a connecting piece 23 on an L-shaped frame portion 21, and a ground terminal 30 integrally formed with a lead portion 32 and a connecting portion 33.
And a piezoelectric vibrator 40 having an input electrode 41 and an output electrode 42 on the front surface and a ground electrode 43 on the back surface.
In the middle of the rectangular area surrounded by the frame portion 11 of the input terminal 10 and the frame portion 21 of the output terminal 20 with the lead portions 12, 22, 32 of the three terminals arranged in parallel on the same plane. The piezoelectric vibrator 40 is arranged in, the connection piece 13 is connected to the input electrode 41,
Connect the connection piece 23 to the output electrode 42 and connect it to the ground terminal.
Bending 30 connects the connecting portion 33 to the ground electrode 43. [Effect] The assembly is performed continuously on the lead frame, the productivity is good, and the assembly can be easily automated.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a structure of a three-terminal type ceramic filter using a strip-shaped piezoelectric vibrator.

[0002]

[Prior art]

 A conventional ceramic filter of this type is shown in FIG. This is because the input terminal 1 and the output terminal 2 are planted in the lower portion of the base 3, and the pair of ridges 1a and 2a formed respectively on the terminals 1 and 2 are projected into the concave portion 3a of the base 3, and the concave portion 3 is formed. The electrode on the lower surface of the piezoelectric vibrator 4 mounted in a is brought into contact with the ridges 1a and 2a, and the ground terminal 5 is fixed to the upper surface of the base 3 to fix the ridge 5a to the electrode on the upper surface of the piezoelectric vibrator 4. 4a is brought into contact with the ground terminal 5 by utilizing the elasticity of the ground terminal 5, the case 6 is covered, and the projection 3b of the base 3 is fitted into the window hole 6a.

[0003]

[Problems to be solved by the device]

 However, in such a configuration, the assembly is complicated, such as insert molding of the terminals 1 and 2 and the base 3 and the incorporation of the ground terminal 5, and the connection state of the piezoelectric vibrator and the terminal is affected by the variation of the contact pressure. There was a problem that was easily received.

[0004]

[The purpose of the device]

 SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned conventional drawbacks and to provide a ceramic filter which is easy to assemble automatically and has high productivity and which has a stable connection state between the piezoelectric vibrator and the terminal. To do.

[0005]

[Means for Solving the Problems]

 The ceramic filter of the present invention has an input terminal in which a lead portion and a connecting piece are integrally molded in a substantially L-shaped frame portion, and an output terminal in which the lead portion and a connecting piece are integrally molded in a substantially L-shaped frame portion. , A grounding terminal in which the lead portion and the connecting portion are integrally molded, and a piezoelectric vibrator having an input electrode and an output electrode on the front surface and a grounding electrode on the back surface. And the lead parts of the output terminal and the ground terminal are arranged in parallel on the same plane, and the piezoelectric vibrator is arranged in a substantially rectangular area surrounded by the frame part of the input terminal and the frame part of the output terminal. The input terminal connecting piece is connected to the input electrode, the output terminal connecting piece is connected to the output electrode, and the earth terminal is bent to connect the connecting portion to the ground electrode.

[0006]

【Example】

 1 and 2 show an embodiment of the ceramic filter of the present invention. In these figures, 10 is an input terminal in which a lead portion 12 and a connecting piece 13 are integrally formed on a wide frame portion 11 having a substantially L shape, and 20 is a lead portion 21 having a substantially L shape similar to the frame portion 11. An output terminal in which the portion 22 and the connecting piece 23 are integrally molded. The lead portion 12 is drawn out from the corner of the L-shaped frame portion 11, and the lead portion 22 is drawn out from one end of the L-shaped frame portion 21. Reference numeral 30 is a ground terminal integrally formed with the lead portion 32 and connection portion 33, and 40 is a piezoelectric vibrator having an input electrode 41 and an output electrode 42 on the front surface and a ground electrode 43 on the back surface. The piezoelectric vibrator 40 stretches and vibrates in the length direction. The input terminal 10, the output terminal 20 and the ground terminal 30 are arranged such that the lead portions 12, 22, 32 of the respective terminals are located on the same plane and are parallel to each other with the ground terminal 30 as the center.

A piezoelectric vibrator 40 is attached in a substantially rectangular area surrounded by the frame portion 11 and the frame portion 21. From the facing surfaces of the frame portions 11 and 21, the connecting piece 13 and the connecting piece 23 extend in parallel to the respective terminal portions 12, 22, and 32 toward the central portion of the piezoelectric vibrator 40, which is a node of vibration. ing. The connecting piece 13 of the input terminal 10 is soldered to the input electrode 41, and the connecting piece 23 of the output terminal 20 is soldered to the output electrode 42 at the center of the piezoelectric vibrator 40 in the longitudinal direction. The ground terminal 30 is formed by bending so that the connecting portion 33 is located on the side of the ground electrode 43 of the piezoelectric vibrator 40, and the tip of the connecting portion 33 is soldered to the ground electrode 43. Then, with the void 50 formed around the piezoelectric vibrator 40, the portion excluding the lead portions 12, 22, and 32 is covered with a resin layer 60 made of a thermosetting resin or the like.

Next, a method for manufacturing the ceramic filter will be described with reference to FIGS. First, one conductive plate is punched to form a lead frame 70 as shown in FIG. 3 in which the input terminal 10, the ground terminal 30, and the output terminal 20 are continuously provided. Then, as shown in FIG. 4, the tip of the grounding terminal 30 is separated from the frame portion 11 of the input terminal 10, and the grounding terminal 30 is bent and formed so that the connecting portion 33 is located downward in the drawing. Next, the piezoelectric vibrator 40 is attached in a substantially rectangular area 80 (FIG. 4) surrounded by the frame portion 11 and the frame portion 21, and the connecting piece 13 of the input terminal 10 is connected to the input electrode 41 as shown in FIG. Then, the connection piece 23 of the output terminal 20 is soldered to the output electrode 42. Further, as shown in FIG. 6 in which the lead frame 70 is turned upside down, the lead portions 12, 22 of the input terminal 10 and the output terminal 20 are arranged so that the connecting portion 33 of the earth terminal 30 faces the earth electrode 43 of the piezoelectric vibrator 40. The length is shortened by bending and forming the connection part 33 to the ground electrode 43.

After that, for example, the piezoelectric vibrator 40 is coated with wax and then immersed in a molten resin for exterior such as DuPont (trademark) manufactured by DuPont to remove the leads 12, 22, 32. The remaining portion is covered with the resin layer 60, and the resin layer 60 is further heated and cured, and at the same time, the wax around the piezoelectric vibrator 40 is melted out through the porous resin layer 60, or A space 50 is formed between the piezoelectric vibrator 40 and the resin layer 60 by removing it by absorbing it. Then, the three terminals 10, 20 and 30 are separated from the lead frame 70, and the ceramic filter as shown in FIGS. 1 and 2 is completed. As a method of forming the voids 50, other known means such as using a resin layer 60 that shrinks when irradiated with ultraviolet rays can be used. Further, in the above embodiment, the tip of the ground terminal 30 is connected to the frame portion 11 of the input terminal 10 in order to facilitate handling of the lead frame 70, but the tip of the ground terminal 30 is punched out of the lead frame 70. It may be separated from the frame portion 11 from the beginning at the time of molding.

[0010]

[Effect of device]

 The ceramic filter of the present invention is constructed so as to be continuously assembled on the lead frame, has high productivity and is easy to assemble automatically. Further, since the connection piece integrally molded with the terminal is directly connected to the piezoelectric vibrator by means of soldering or the like, a stable and highly reliable ceramic filter in which the piezoelectric vibrator and the terminal are connected can be obtained.

[Brief description of drawings]

1 is a sectional view taken along the line AA of FIG. 2 showing an embodiment of the present invention.

FIG. 2 is a side sectional view of the same.

FIG. 3 is a process diagram showing a method for manufacturing the same ceramic filter.

FIG. 4 is a process diagram showing a method for manufacturing the same ceramic filter.

FIG. 5 is a process drawing showing the method for manufacturing the same ceramic filter.

FIG. 6 is a process diagram showing a method for manufacturing the same ceramic filter.

FIG. 7 is an exploded perspective view showing a conventional example.

[Explanation of symbols]

 10 Input terminal 11 ・ 21 Frame part 12 ・ 22 Lead part 20 Output terminal 30 Ground terminal 32 Lead part 40 Piezoelectric vibrator 41 Input electrode 42 Output electrode 43 Ground electrode

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Minoru Sawada Minoru Sawada 828 Hinohara, Hamahara, Tamagawa-mura, Hiki-gun, Saitama Prefecture Toko Co., Ltd.Tamagawa Factory (72) Shinkichi Umezu, 828 Hinohara, Hinohara, Hiki-gun, Hiki-gun, Saitama Prefecture Tamagawa factory

Claims (1)

[Scope of utility model registration request] 1. An input terminal in which a lead portion and a connecting piece are integrally molded in a substantially L-shaped frame portion, an output terminal in which a lead portion and a connecting piece are integrally molded in a substantially L-shaped frame portion, and a lead. And a connecting portion are integrally molded, and a grounding terminal, and a piezoelectric vibrator having an input electrode and an output electrode on the front surface and a grounding electrode on the back surface. Place the lead parts of the ground terminals in parallel on the same plane, and place the piezoelectric vibrator in the approximately rectangular area surrounded by the frame part of the input terminal and the frame part of the output terminal. Is connected to the input electrode, the connecting piece of the output terminal is connected to the output electrode, and the earth terminal is bent to connect the connecting portion to the earth electrode.