JP2829858B2 - Chip type capacitor and manufacturing method thereof - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement in a capacitor, and more particularly to a chip-type capacitor suitable for surface mounting on a substrate.

[Conventional technology]

Conventionally, in order to realize a capacitor chip, the capacitor element was subjected to resin molding, the lead wire for external connection derived from the resin end face was bent along the resin side face, and faced the wiring pattern of the printed board .

Alternatively, for example, as in the invention described in Japanese Utility Model Publication No. 59-3557, a capacitor in which a conventional capacitor is housed in an exterior frame and lead wires are arranged on substantially the same plane as an end surface of the exterior frame has been proposed. . Further, as in the inventions described in JP-A-60-245116 and JP-A-60-245115,
A capacitor has been proposed in which a capacitor is placed in a bottomed cylindrical outer frame, a lead wire is derived from a through hole in the bottom surface of the outer frame, and the lead wire is bent so as to be accommodated in a concave portion provided on the outer surface of the outer frame. ing.

[Problems to be solved by the invention]

However, in a chip-type capacitor subjected to molding, the capacitor element may be thermally degraded due to thermal stress at the time of molding, and many parts are structurally different from conventional capacitors, and the manufacturing method is complicated.

In addition, when a conventional capacitor, that is, a capacitor in which the opening end and the side surface of the outer case are sealed with a groove that tightens the outer case is housed in the outer frame, the gap between the groove on the outer case side and the inner surface of the outer frame is stored. A space is created. Then, the air existing in the space expands due to solder heat or the like, which may cause the capacitor body to protrude from the exterior frame or damage the exterior frame.

When soldering electronic components, there is a method using a reflow furnace. In the case of this reflow method, the temperature of the reflow furnace is basically restricted by the heat-resistant temperature of the outer frame made of synthetic resin or the like. However, heat is actually conducted from the outer frame to the electronic component body. Therefore, the temperature of the exterior frame is lower by about 10 ° C. than the temperature of the reflow furnace, and soldering in a temperature range higher than the heat-resistant temperature of the synthetic resin forming the exterior frame becomes possible.

However, the capacitor body and the outer frame are not in contact with each other in the groove on the side surface of the capacitor. Therefore, in this non-contact portion, the heat of the reflow furnace is not directly conducted to the capacitor body. For this reason, the outer frame may be partially softened and melted, which causes inconvenience such as poor appearance and makes it difficult to make the capacitor into a chip.

An object of the present invention is to realize a chip-type capacitor that can be operated and used in a high temperature range.

[Means for solving the problem]

The present invention is configured such that a capacitor which is tightly sealed by a groove provided in a side surface portion of an outer case and has an annular body fitted in the groove is housed in an outer frame having a storage space adapted to an outer diameter of the capacitor, The lead wire derived from the end face of the capacitor is bent along the opening face and the bottom face of the exterior frame.

Further, as another means, a capacitor provided with a resin layer in the groove portion, which is tightly sealed by a groove portion provided on a side surface portion of the outer case, is formed into an outer frame having a storage space adapted to the outer diameter of the capacitor. It is characterized in that the lead wire housed and led out from the end face of the capacitor is bent along the opening face and the bottom face of the exterior frame.

As another means, the capacitor tightly sealed by the groove provided on the side surface of the outer case is housed in an outer frame having a storage space adapted to the outer diameter of the capacitor, and the capacitor is housed in the outer frame. There is a manufacturing method in which a resin is injected and solidified from a through hole provided in a part of an exterior frame to close a groove of a capacitor.

(Operation)

As shown in the drawing, the storage space 13 of the exterior frame 2 stores the capacitor 1 in which the annular body 8 or the resin layer 9 is disposed in the groove provided on the side surface. Therefore, the inner surface of the storage space 13 of the outer frame 2 and the capacitor 1 are in close contact with each other. Therefore, the reflow heat in the soldering process is uniformly conducted to the capacitor 1 body. And the temperature distribution on the surface of the exterior frame 2 becomes uniform, and the local high-temperature portion is eliminated.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.
FIG. 1 is a partial sectional perspective view showing an embodiment of the present invention,
FIG. 2 is a partial sectional view showing a second embodiment of the present invention. FIG. 3 is a partial sectional view for explaining a manufacturing method according to a third embodiment of the present invention.

The capacitor 1 body houses a capacitor element formed by winding an electrode foil (not shown) and electrolytic paper (not shown) in a bottomed cylindrical outer case made of aluminum or the like, and attaches a sealing body 4 to an opening end of the outer case. At the same time, the opening end of the outer case is tightened and sealed, and a groove 7 is formed on the side surface of the outer case.
Are formed to seal the capacitor 1. And the first
As shown in the figure, a lead wire 3 led from a capacitor element is penetrated through the sealing body 4 and is drawn out to the outside.

An annular body 8 is fitted into the groove 7 on the side surface of the capacitor 1. The annular body 8 is made of a metal ring such as aluminum, and has a cut portion at a part thereof, and is formed to be openable and closable.

The capacitor 1 in which the annular body 8 is fitted into the groove 7 is
The capacitor 1 is housed in an exterior frame 2 having a cylindrical storage space 13 adapted to the outer diameter and outer shape of the capacitor 1. It is desired that the exterior frame 2 be made of a material having excellent heat resistance.
Preferably, a heat-resistant synthetic resin such as epoxy, phenol, or polyimide having excellent heat resistance, or a ceramic material is suitable.

In this embodiment, the storage space 13 of the outer frame 2 is formed in a cylindrical shape having an inner diameter substantially the same as the outer diameter of the capacitor 1 because the outer shape of the capacitor 1 is used in this embodiment. When a non-cylindrical capacitor, for example, a capacitor having an elliptical cross-sectional shape is used, an exterior frame having an elliptical cylindrical storage space suitable for the shape is used.

In addition, a protrusion 5 that covers a part of the opening surface is provided on one of the end surfaces of the exterior frame 2. The protrusion 5 comes into contact with the end face of the capacitor 1 stored in the storage space 13 of the outer frame 2. Therefore, the main body of the capacitor 1 is fixed in the storage space 13 of the outer frame 2 by the protrusions 5 and the bent lead wires 3.

The lead wire 3 protruding from the capacitor 1 housed in the exterior frame 2 is bent along the opening surface and the bottom surface of the exterior frame 2 near the front end portion and the center of the lead wire 3, and is formed on the bottom surface of the exterior frame 2. It is stored in the notch 6 provided.

In the case of this embodiment, a capacitor 1 having a normal structure can be used. Therefore, the capacitor 1
The sealing performance of the main body can be maintained at the same level as before, and the reliability is excellent. Then, the outer surface of the capacitor 1
The annular body 8 comes into contact with the inner surface of the storage space 13 of the exterior frame 2 without any gap on one surface.

In this embodiment, the annular body 8 has a circular cross section. However, the annular body 8 may have any other shape such as an elliptical shape, a trapezoidal shape, or a rectangular shape suitable for the shape of the groove. In addition to a metal ring such as aluminum, a synthetic resin ring having high thermal conductivity can be used.

Next, a second embodiment of the present invention shown in FIG. 2 will be described.

As in the case of the above embodiment, the capacitor 1 has a capacitor element housed in an outer case and has a sealing body 4
Is attached, and the opening end and side surfaces of the outer case are tightly sealed.

A resin layer 9 made of a heat-resistant synthetic resin such as epoxy, phenol, or polyimide having excellent heat resistance is formed in the groove 7 of the capacitor 1 body. The outer peripheral dimension of the resin layer 9 is formed substantially the same as the outer peripheral dimension of the capacitor 1 body.

The main body of the capacitor 1 in which the resin layer 9 is formed in the groove 7 is
Similarly to the first embodiment, the lead wire 3 housed in the exterior frame 2 having the storage space 13 and led out from the capacitor 1 is bent along the opening surface and the bottom surface of the exterior frame 2.

In the case of this embodiment, as compared with the first embodiment, the exterior frame 2 and the main body of the capacitor 1 come into close contact with almost no gap, and the gap is further reduced.

Next, a third embodiment of the present invention shown in FIG. 3 will be described.

The main body of the capacitor 1 is formed in the same manner as that used in the first and second embodiments. In addition, the outer frame 2
A through hole 11 for injecting resin and a through hole 12 for venting air are provided at arbitrary positions corresponding to the grooves 7 of the capacitor 1 to be housed.

After the main body of the capacitor 1 is housed in the outer frame, the heat-resistant synthetic resin 1 is inserted through the through hole 11 for resin injection.
0, for example, an epoxy resin, a phenol resin or the like is injected and filled.

In this embodiment, the groove 7 of the capacitor is filled with the resin 10 after the main body of the capacitor 1 is housed in the outer frame 2. Therefore, as compared with the first and second embodiments, the main body of the capacitor 1 and the storage space 13 of the outer frame 2 are more closely adhered to each other.

In addition, since the resin 10 is filled after the main body of the capacitor 1 is housed in the outer frame 2, it is also possible to fix the main body of the capacitor 1 to the housing space 13 of the outer frame 2.

In any of the above embodiments, when the lead wire 3 is bent, a flat portion is provided on a part of the lead wire 3 and the lead wire 3 is bent from the flat portion as a base point, thereby facilitating the bending process.

〔The invention's effect〕

As described above, the present invention provides an external frame having a storage space which is tightly sealed by a groove provided in a side surface portion of an external case and in which an annular body is fitted in the groove, and which has a storage space adapted to the outer diameter of the capacitor. And the lead wire led out from the end face of the capacitor is bent along the opening surface and the bottom surface of the exterior frame, so that the space between the storage space of the exterior frame and the capacitor body is reduced. Therefore, even when the chip-type capacitor according to the present invention is mounted on a printed circuit board and subjected to a soldering process such as reflow, the storage space of the outer frame does not expand, preventing the capacitor main body from projecting and the outer frame from being deformed. can do.

Further, the reflow heat in the reflow processing or the like is uniformly conducted to the capacitor body. Therefore, the temperature distribution on the outer surface of the exterior frame becomes uniform, and it is possible to prevent the temperature from becoming partially high. Therefore, the deformation and melting of the outer frame due to the temperature distribution imbalance as in the related art are eliminated. Further, since the set temperature of the reflow furnace can be set higher than before, the efficiency of the soldering step is improved.

Further, the effect of preventing the capacitor body from projecting or the like can be obtained without changing the structure of the capacitor body, particularly the sealing structure, as compared with a normal capacitor. Therefore, it is possible to make the capacitor into a chip while maintaining the same sealing accuracy as that of a normal capacitor, that is, while maintaining the reliability.

Further, when a resin layer is provided in the groove, the closed state in the groove is further improved, and the heat dissipation can be improved more than the first means.

Further, after the capacitor is housed in the outer frame, the resin is injected and solidified through a through hole provided in a part of the outer frame to close the groove of the capacitor. The resin becomes an adhesive, and the storage state of the capacitor in the storage space of the outer frame is strengthened, and the reliability is further improved.

[Brief description of the drawings]

FIG. 1 is a partial sectional perspective view showing an embodiment of the present invention,
FIG. 2 is a partial sectional view showing a second embodiment of the present invention. FIG. 3 is a partial sectional view for explaining a manufacturing method according to a third embodiment of the present invention. 1 ... capacitor, 2 ... outer frame, 3 ... lead wire, 4
... sealing body, 5 ... projection, 6 ... notch, 7 ... groove, 8 ... annular body, 9 ... resin layer, 10 ... resin, 11, 12 ... through-hole, 13 ... ... storage space.

Claims (3)

(57) [Claims] A capacitor, which is tightly sealed by a groove provided on a side surface of an outer case and has an annular body fitted in the groove, is housed in an outer frame having a housing space adapted to an outer diameter of the capacitor. A chip-type capacitor characterized in that a lead wire derived from an end face of the capacitor is bent along an opening surface and a bottom surface of an exterior frame. 2. A capacitor which is tightly sealed by a groove provided on a side surface of an outer case and has a resin layer provided in the groove is housed in an outer frame having a housing space adapted to the outer diameter of the capacitor. A chip-type capacitor characterized in that a lead wire derived from an end face of the capacitor is bent along an opening surface and a bottom surface of an exterior frame. 3. A capacitor tightly sealed by a groove provided in a side surface portion of an outer case is housed in an outer frame having a housing space adapted to the outer diameter of the capacitor, and the capacitor is housed in the outer frame. A method for manufacturing a chip-type capacitor, comprising: injecting and solidifying a resin through a through hole provided in a part of an exterior frame to close a groove of the capacitor.