JPH056931U - Surface mount type piezoelectric component - Google Patents

Abstract

(57) [Summary] [Purpose] In surface-mounted piezoelectric components, a resin that seals the opening of the case can be bent accurately with the external lead-out part of the terminal parallel to the surface of the case. Prevent peeling. [Structure] The terminal lead-out portion 10 is provided in the opening 3 of the case 1.
A guide member 21 for holding a and 11b at predetermined heights H1 and H2 is provided. The lead portions 10a, 11b are bent downward with the corner portions 22a ', 22b' of the guide member 21 as positioning portions.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a surface mount type piezoelectric component in which an internal component including a piezoelectric element and a terminal is housed in a case.

[0002]

[Prior Art]

 In recent years, surface mount type devices have been required for various devices mounted on a wiring board, and various measures have been taken even for ladder filters. FIG. 4 shows a part of such a surface-mounted ladder filter in which an insulating paper 31 is set in the opening of the case 30 and an epoxy resin 32 is filled and hardened by potting. The input / output terminals 33, 34 project outward from the resin 32 and are bent at two locations indicated by arrows A, B. In this case, it is preferable that the lead-out portions 33a and 34a of the terminals 33 and 34 be located as parallel to the bottom surface of the case 30 as possible.

However, in the conventional ladder filter, due to the displacement of the insulating paper 31 and the variation in the filling amount of the epoxy resin 32, as shown in FIG. Bending may be performed in the lifted state. Reference numeral 35a is a ground terminal lead-out portion. Such products have problems such as poor soldering to the wiring board and higher mounting height than the standard. Further, the resin 32 peels off from the inner surface of the case 30 due to the stress generated in the epoxy resin 32 during bending (in many cases, the portion indicated by the arrow c peels off), or peels between the resin 32 and the terminals 33 and 34. Occurs, and the hermeticity inside the case 30 is impaired.

[0004]

[Purpose, configuration, operation of the device]

 Therefore, an object of the present invention is to provide a surface-mounted piezoelectric component in which the external lead-out portion of the terminal can be accurately bent in parallel with the surface of the case and the sealing resin does not peel off. Especially. In order to achieve the above object, the surface-mounted piezoelectric component according to the present invention is provided with a guide member for holding the lead portion of the terminal at a predetermined height at the opening portion of the case, and positioning the corner portion of the guide member. It is characterized in that the lead portion of the terminal is bent as a part.

The lead-out portion of the terminal is held at an accurate position by the guide member, and is bent based on the position. Therefore, the accuracy of the bending process is improved, and the drawer portion comes into close contact with the case. Further, the sealing resin may be filled in the opening of the case after the bending process, and is not peeled off from the case due to the stress generated during the bending process. Of course, the opening may be filled with a resin for sealing before the bending process. Even in this case, the bending force applied to the terminal is received by the guide member, does not act on the resin, and the resin does not peel in any case.

[0006]

【Example】

 Hereinafter, embodiments of the surface mount type piezoelectric component according to the present invention will be described with reference to the accompanying drawings. The embodiment described below is a ladder filter. In FIG. 1, the ladder filter includes a case 1, four piezoelectric elements 5, 6, 7, and 8, an input terminal 10 and an output terminal 11, a relay terminal 12, a ground terminal 15, and a spring plate 19. It is configured. The piezoelectric elements 5, 6, 7, and 8 are well-known ones having electrodes on the front and back surfaces, respectively.

The case 1 is integrally formed of a resin material such as polyphenylene sulfide or epoxy, and has an opening 3 on one side surface. As shown in FIG. 3, each of the terminals 10, 11, 12, and 15 is provided with a projection, and the piezoelectric elements 5, 6, 7, and 8 are sandwiched by these projections, and the spring plate 19 entirely covers the case. It is held elastically within 1. The ground terminal 15 is attached in advance to the other side wall portion 2 of the case 1 by insert molding or insertion, and other parts are housed in the case 1 through the opening 3.

In the opening 3 of the case 1, the insulating paper 20 and the guide member 21 are set in a state where the lead-out portions 10 a and 11 a of the terminals 10 and 11 are straightly extended. As shown in FIG. 2, the guide member 21 is on a block having pedestals 22a and 22b of heights H1 and H2 corresponding to the drawers 10a and 11a, and is made of a relatively rigid phenol, epoxy, or the like. It is molded from resin. The drawer portions 10a, 11a are bent downward while being held at a predetermined height by the pedestals 22a, 22b of the guide member 21, that is, the corner portions 22a ', 22b' functioning as positioning portions. Further, it is bent so as to be parallel to the bottom surface of the case 1. The lead-out portion 15a of the earth terminal 15 is also bent along the surface of the case 1. Since the case 1 itself serves as a positioning portion and is bent, the lead-out portion 15a is bent accurately.

After that, the epoxy resin 25 is potted in the opening 3 to seal the inside of the case 1. It is preferable to form notches 23a, 23b, 23c in the guide member 21 at arbitrary positions so that the molten resin can be easily filled between the insulating paper 20 and the guide member 21 when the resin 25 is potted. The molten resin flows in between the drawer portions 10a and 11a and the guide member 21 by a capillary phenomenon, and the hermeticity inside the case is secured.

According to the above configuration, the lead-out portions 10a and 11a of the terminals 10 and 11 are positioned and bent by the guide member 21, so that the displacement of the insulating paper 20 and the filling amount of the potting resin are increased as in the conventional case. Accurate bending, the parts 10a and 11a float up from the bottom of the case 1, and soldering failure may occur during mounting on the wiring board, or the mounting height is out of specification. There is no inconvenience.

Further, since the sealing resin 25 is potted after the bending process, no stress is generated during the bending process, and peeling occurs between the inner surface of the case 1 and the terminals 10 and 11. There is no. Alternatively, after the resin 25 is potted and cured, the lead portions 10a and 11a may be bent. Even in such a process, the bending force is not applied to the resin 25 but only to the guide member 21, the resin 25 is not peeled off like the above, and the hermeticity inside the case 19 is secured. ..

[0012]

[Effect of the device]

 As is clear from the above description, according to the present invention, the guide member is provided in the opening of the case to function as the positioning portion when bending the lead portion of the terminal, so that the lead portion can be bent accurately. This eliminates the trouble (soldering failure, mounting height variation) during mounting on the wiring board. In addition, stress due to bending does not occur in the sealing resin with which the opening of the case is filled, and peeling of the sealing resin and the resulting defective sealing inside the case do not occur.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a ladder filter according to an embodiment of the present invention.

FIG. 2 is a front view of the ladder filter shown in FIG. 1 immediately before a terminal bending process.

3 is a cross-sectional view showing a completed product of the ladder filter shown in FIG. 1, and the left portion in the drawing is shown as a cross section corresponding to line XX in FIG.

FIG. 4 is a partial sectional view of a conventional ladder filter.

FIG. 5 is a side view of a conventional ladder filter.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Case 5, 6, 7, 8 ... Piezoelectric element 10 ... Input terminal 10a ... Draw-out part 11 ... Output terminal 11a ... Draw-out part 20 ... Insulating paper 21 ... Guide member 22a, 22b ... Pedestal part 22a ', 22b' ... Corner Part 25 ... Resin for sealing

Claims (1)

[Claims for utility model registration] [Claim 1] An internal component including a piezoelectric element and a terminal is housed in a case, the terminal extends outward from an opening of the case, and is bent along a side surface of the case, and In a surface-mounted piezoelectric component in which the opening of the case is sealed with resin, a guide member for holding the lead-out portion of the terminal at a predetermined height is provided in the opening of the case, and a corner portion of the guide member serves as a positioning portion. A surface-mounted piezoelectric component characterized in that the lead-out parts of the terminals are bent.