JPH045250B2 - - Google Patents

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to an electronic component having an elongated electronic component body, such as a cylindrical or cylindrical capacitor with an open end or both ends. This invention relates to an improvement for improving the bending strength of a component body.

[Summary of the Invention] The present invention provides an electronic component having a long electronic component body, in which fibers mainly oriented in the longitudinal direction of the electronic component body are hardened with a resin so as to surround the outer periphery of the electronic component body. By forming the layer, the flexural strength of the electronic component body is increased or the flexural strength is prevented from decreasing.

[Prior Art] Examples of objects to which this invention is directed include:
There are cylindrical capacitors and cylindrical capacitors as shown in FIGS. 6 and 7, respectively.

The cylindrical capacitor shown in FIG. 6 includes a cylindrical dielectric 1 made of, for example, ceramic, and has electrodes 2 and 3 formed on its inner and outer circumferential surfaces, respectively. The electrode 2 on the inner peripheral surface is formed to extend from one end surface of the dielectric 1 to a part of the outer peripheral surface. On the other hand, the electrode 3 on the outer peripheral surface is
It is formed so as to extend to the other end of the dielectric 1. Usually, each end of the dielectric 1 is covered with metal caps 4 and 5, which serve as external terminals, and one metal cap 4 is connected to an electrode 2 formed on the inner peripheral surface of the dielectric 1 by soldering. The other metal cap 5 is soldered to the electrode 3 formed on the outer peripheral surface of the dielectric 1. Note that, as shown by phantom lines, lead wires 6 and 7 extending in the axial direction may be connected to the metal caps 4 and 5.

In such a cylindrical capacitor, in order to electrically insulate it from the outside, an exterior material 8 is formed to cover the main body of the capacitor except for the main parts of the metal caps 4 and 5. This exterior material 8 includes
For example, a thermosetting resin such as epoxy resin is used.

In the cylindrical capacitor shown in FIG. 7, a solid dielectric 1 made of ceramic, for example, is used.
1, and electrodes 12 and 13 are formed on the outer surface of each end thereof, respectively. In addition, the dielectric 11
Metal caps 14 that serve as external terminals are provided at both ends of the
and 15 are covered and soldered to electrodes 12 and 13, respectively.

In this cylindrical capacitor as well, an exterior material 16 is formed to cover the capacitor body except for the main parts of the metal caps 14 and 15 in order to achieve electrical insulation from the outside.

[Problems to be Solved by the Invention] Cylindrical or cylindrical capacitors as described above are usually handled in a so-called chip state when they are mounted on a suitable printed circuit board, and furthermore, this handling is not automatic. It is done by machine.
The automatic machine is equipped with a chuck for gripping a chip-shaped electronic component such as the above-mentioned capacitor, and such a chuck grips the cylindrical or cylindrical capacitor by sandwiching it in the longitudinal center. The main body of the capacitor sometimes cracked or broke. This is due to the thinness of the dielectric 1 in the case of a cylindrical capacitor and the thinness of the dielectric 11 in the case of a cylindrical capacitor. For cylindrical capacitors, dielectric 1
The wall thickness of some is as thin as around 0.2mm. In addition,
Damage to the main body of a capacitor is not limited to the damage caused by the chuck mentioned above, but can occur in any process.

As mentioned above, damage to the capacitor body, particularly caused by chuck gripping, is to some extent eliminated by the formation of the outer jacket 8 or 16. However, on the other hand, in the case of cylindrical capacitors, for example, in order to obtain large capacitance, the dielectric material
There is a tendency for the wall thickness to become even thinner. Processing by automatic machines will also be faster, and therefore the operating speed of the chuck will necessarily be increased. As a result, the impact exerted on the capacitor body when the chuck performs the gripping operation also becomes larger. Due to these trends, the capacitor body has an increased chance of being damaged during handling, so it is important to improve the mechanical strength of the capacitor body, especially the bending strength, or to prevent the decline in the bending strength. It is hoped that this will be done.

Note that if the exterior material 8 or 16 is formed thickly,
Although the above-mentioned improvement in bending strength is brought about, such measures have limitations. Because exterior material 8
Or as the cost of materials for 16 increases,
If the exterior material 8 or 16 is formed too thick, the chip-shaped electronic component will have a bulging shape near the longitudinal center, and the metal caps 4, 5 or 14, 15 provided at both ends will become a printed circuit board. This is because the soldering pattern may be lifted high from the conductive pattern, making it difficult to stably achieve the desired soldering.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide a structure for an electronic component in which the bending strength of the main body of the electronic component is improved or reduced without causing the above-mentioned problems.

[Means for Solving the Problems] The present invention is directed to an electronic component having an elongated electronic component body, as exemplified by the above-mentioned cylindrical or cylindrical capacitor. The challenges are disclosed as follows.

That is, fibers mainly oriented in the longitudinal direction of the electronic component body are hardened with resin so as to surround the outer periphery of the electronic component body.

[Operations and Effects of the Invention] According to the present invention, at least a part of the fibers hardened by the resin on the outer periphery of the electronic component body are mainly oriented in the longitudinal direction of the electronic component body, so that the fibers themselves have High tensile strength works to increase the bending strength of the electronic component body. Therefore, it is possible to obtain an electronic component main body that has high bending strength, or an electronic component main body that does not have a decrease in bending strength even if the wall thickness of a cylindrical electronic component main body or the thickness of a columnar electronic component main body is reduced. be able to.

Therefore, it is possible to prevent damage from being handled by an automatic machine, and it is possible to cope with higher speeds of automatic machines without any problems. Further, even if the thickness of the dielectric is made thinner in order to obtain a large capacity, as in the case of a cylindrical capacitor, for example, a decrease in bending strength can be prevented.

In addition, high bending strength can be obtained while keeping the external dimensions small without increasing the thickness of the exterior material, so processing operations on printed circuit boards are not hindered.

Furthermore, even if the electronic component body is subjected to various processing such as forming grooves or applying sandblasting, the fibers maintain a predetermined or higher bending strength.

[Embodiment] An embodiment of the present invention will be described below with reference to FIGS. 1 to 5, in which the electronic component main body 21 is schematically shown. That is, in these drawings, the electronic component main body 21 is shown as a simple round rod,
Metal caps 22 and 23 are fitted into both ends thereof. The electronic component main body 21 corresponds to a component including the dielectric 1 and the electrodes 2 and 3 in the cylindrical capacitor shown in FIG. and 13. In this way, the electronic component main body 21 is intended to be simply shown as an electronic component main body for a general electronic component rather than a specific electronic component, so this part and the metal caps 22, 2
3, only the outer surface is omitted and not the cross section, and only the components formed to cover the electronic component body 21 are shown in the cross section.

First, a first embodiment of the present invention is shown in FIG. A fiber reinforced layer 24 is formed on the outer peripheral surface of the electronic component body 21. This fiber reinforced layer 24 contains fibers 25 oriented in the longitudinal direction of the electronic component main body 21, and the fibers 25 are hardened with a resin 26.

In the second embodiment of the present invention shown in FIG. 2, a fiber reinforced layer 27 is first formed on the outer peripheral surface of the electronic component body 21, similar to the first embodiment. Then, an exterior material 28 is formed thereon, similar to conventional electronic components. Any resin can be used as the exterior material 28, but preferably a thermosetting resin such as epoxy resin is used.

In the third embodiment of the present invention shown in FIG.
is formed. This exterior material 29 is made of the same material as the exterior material 28 in FIG. In this embodiment, a fiber reinforced layer 30 is formed on the exterior material 29. This fiber reinforced layer 30 is also made by hardening fibers 31 oriented in the longitudinal direction of the electronic component body 21 with a resin 32, like the fiber reinforced layer 24 in FIG. 1, for example.

In the fourth embodiment of the present invention shown in FIG. 4, a fiber reinforced layer 33 is first formed on the outer peripheral surface of the electronic component main body 21.
It is formed into a tube shape from fibers. That is, for example, it is possible to first produce yarn from fibers and use this yarn to weave or knit into a tube shape, or to form tubes made of nonwoven fabric directly from the fibers. Tube-shaped fiber reinforced layer 3
3 is placed so as to surround the outer periphery of the electronic component main body 21. Note that this fiber-reinforced layer 33 may be formed by wrapping a planar cloth around the outer peripheral surface of the electronic component main body 21. An exterior material 34 is formed on the fiber reinforced layer 33. The exterior material 34 is made of resin, like the aforementioned exterior material 28 or 29, and this exterior material 34 itself functions to harden the fibers included in the fiber reinforced layer 33.

Note that instead of hardening the fibers included in the fiber-reinforced layer 33 only with the sheathing material 34, the fiber-reinforced layer 33 may be impregnated with a resin. Therefore, in this fourth embodiment, the exterior material 34 is not particularly necessary.

A fifth embodiment of the invention shown in FIG.
Similar to the second embodiment shown in the figure, the fiber reinforced layer 2
7 and an exterior material 28 are formed. This fifth
The embodiment is characterized by the shape of the electronic component main body 21. That is, a groove 35 extending in the circumferential direction is formed on the outer peripheral surface of the electronic component main body 21.
For example, in the cylindrical capacitor shown in FIG. 6, this groove 35 is formed at the boundary between electrode 2 and electrode 3, and is intended to increase the creepage distance between the two electrodes and increase the voltage resistance. It is something. Processing such as forming the groove 35 is performed on the electronic component body 21.
However, such a decrease can be advantageously prevented by the fiber reinforced layer 27.

In each of the above-mentioned examples, the resin used to harden the fibers includes, for example, epoxy resin, polyimide resin, unsaturated polyester resin,
Thermosetting resins such as phenolic resins are preferred. For example, when the exterior materials 28 and 29 are used as in the embodiments shown in FIGS. 2, 3, and 5, the resin for hardening the fibers should have compatibility or adhesiveness with the exterior material. Taking this into consideration, it is more preferable to use a resin of the same type as the exterior material. In this regard, when a thermosetting resin is used, the resin contained in the fiber reinforced layer and the resin constituting the exterior material may be cured in the same process.

Further, as the fibers included in the fiber reinforced layer used in each example, resins having high tensile strength, heat resistance, and insulation properties are particularly preferable. As such fibers, either organic or inorganic fibers can be used. As organic fibers, aromatic polyamide fibers such as aramid fibers are advantageously used, and as inorganic fibers, for example, glass fibers, silica fibers, alumina fibers, alumina-silica fibers, silicon carbide,
Asbestos, carbon fiber, etc. are advantageously used.
Note that a mixture of several types of fibers may be used.

In addition, as shown in Figures 1 to 3 and Figure 5, when the fibers themselves are used mixed in the resin, such fibers have a thickness on the micron order and a length of 0.3 to 5.0 mm. A thickness of approximately 1 mm is particularly preferred. The amount of fiber mixed with the resin is preferably about 0.1 to 95% by weight, particularly about 0.1 to 10% by weight.

As shown in FIG. 4, in the case of the fiber-reinforced layer 33 having a predetermined shape, the system may be made of short fibers to form a woven or knitted fabric, or yarns are made from long fibers, that is, filaments, and this is woven into a woven fabric. Or you can knit it.

Alternatively, a method may be adopted in which a resin is applied in advance and the fibers are sprinkled thereon while orienting in a certain direction.

As can be inferred from the embodiment shown in FIG. 4, the fact that the fibers are mainly oriented in the longitudinal direction of the electronic component body must be interpreted as follows. That is, the fiber reinforced layer 33 in FIG. 4 may be made of, for example, a fabric in which fibers are arranged in an orderly manner in the length and weft, but in this case, about half of the fibers are arranged in the longitudinal direction of the electronic component body. may not line up. However, it is true that there are many fibers oriented in the longitudinal direction of the electronic component body, and such fibers arranged in the longitudinal direction contribute to improving the bending strength. Therefore, it cannot be limited that 50% or more of the fibers are oriented in the longitudinal direction of the electronic component body, but at least a number of fibers that can contribute to improving the bending strength are oriented in the longitudinal direction of the electronic component body. It would be a good thing if it were. From this, "mainly oriented" means
It cannot be specified as a proportion to the total number of fibers.

Moreover, the "longitudinal direction" does not necessarily have to be exactly the longitudinal direction. Therefore, even if the fibers are oriented in a direction that is slightly deviated from the longitudinal direction, it can contribute to improving the bending strength, and the fibers can be oriented "substantially in the longitudinal direction."
It should be interpreted as Furthermore, in the case of a single fiber, it is only necessary that the main portion of the fiber be oriented substantially in the longitudinal direction, and there is no problem even if a part of the fiber deviates greatly from the longitudinal direction.

Further, although the electronic component main body disclosed in the drawings has a cylindrical or cylindrical shape, it may have a rectangular prism shape, for example.In short, the present invention is applicable to any elongated electronic component main body. I can do it.

Further, even if the electronic component to which the present invention is applied does not include the metal caps 22 and 23,
Conversely, it may be provided with lead wires 6, 7 (FIG. 6).

Furthermore, the present invention is applicable not only to capacitors but also to various other electronic components.

[Brief explanation of drawings]

1, 2, 3, 4 and 5 respectively show first, second, third, fourth and fifth embodiments of the present invention, in which an electronic component main body 21
The portion excluding the metal caps 22 and 23 is shown in a cross-sectional view. FIG. 6 and FIG. 7 are cross-sectional views showing a conventional cylindrical capacitor and a cylindrical capacitor, respectively. In the figure, 21 is the electronic component body, 24, 2
7, 30, 33 are fiber reinforced layers, 25, 31 are fibers, 26, 32 are resins, and 28, 29, 34 are exterior materials.

Claims (1)

[Claims] 1. An electronic component comprising a longitudinal electronic component body, characterized in that fibers mainly oriented in the longitudinal direction of the electronic component body are hardened with a resin so as to surround the outer periphery of the electronic component body.