JPH0223020B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a cylindrical capacitor that can be stably attached to a substrate such as a metal chassis or a printed circuit board.

Conventionally, the ones shown in FIGS. 1 and 2 are typical examples of cylindrical capacitors to be attached to a substrate. The first figure shows a cylindrical capacitor 1 having an inner electrode 2 on the inner circumferential surface and an outer electrode 3 on the outer circumferential surface, and a metal eyelet terminal 4 that is electrically conductive with the outer electrode 3 and fixed to the outer circumferential surface of the cylindrical capacitor 1. The one shown in the second figure is one in which a cylindrical capacitor 1 is integrally formed with a collar 5 projecting outward at one end thereof. When attaching these cylindrical capacitors 1 to a board, one end is inserted into a through hole 7 formed in the board 6, locked with the eyelet terminal 4 or collar 5, and in this state, soldered. It is something that sticks. However, when these conventional cylindrical capacitors 1 are attached to the board 6, the cylindrical capacitors 1 are simply placed in the holes 7 of the board 6, so it is very difficult to handle them until they are fixed with solder. It is in a stable state, and the cylindrical capacitor 1 is not tilted or
There was a problem with it falling off. If the cylindrical capacitor 1 is tilted, it actually has a drawback that it becomes impossible to solder it to the board 6. Furthermore, when soldering the cylindrical capacitor 1 to the board 6, the board 6 is often tilted from the beginning, and if you want to stably attach the cylindrical capacitor 1 to it, you will have to However, until soldering, it must be held using some kind of special holding jig, which has the drawback of making the process extremely complicated. Furthermore, when soldering the cylindrical capacitor 1 and the board 6, the cylindrical capacitor 1 is generally preheated by conduction by heating the board 6. Since the contact area between the shaped capacitor 1 and the board 6 is not very large, and the cylindrical capacitor 1 is simply placed on it, heat conduction is insufficient and the preheating efficiency of the cylindrical capacitor 1 is poor, causing problems during soldering. It also has the disadvantage that cracks may occur in the cylindrical capacitor 1 due to the temperature difference.

The present invention has been made in view of the above-mentioned points, and is characterized in that at least a pair of protrusions are formed on the outer periphery of a cylindrical capacitor that protrudes outward at a constant interval in the length direction. The present invention aims to provide a cylindrical capacitor that

Embodiments of the present invention will be described in detail below with reference to the drawings.

3 to 6 are side sectional views showing examples of the shape of a cylindrical capacitor.

3 and 4 are improved examples of the conventional device shown in FIG. 1, in which one additional metal eyelet terminal 10 is provided. This metal eyelet terminal 10 is externally fitted and fixed to other metal eyelet terminals 4 so as to be spaced apart from each other by a constant distance in the length direction of the cylindrical capacitor 1 . The distance between the two metal eyelet terminals 4 and 10 is approximately matched to the thickness of the substrate 6, and the structure is such that the substrate 6 can be held between the two terminals 4 and 10.

5 and 6 are improved examples of the conventional example shown in FIG. 2. In FIG. 5, a metal eyelet terminal 10 is externally fitted and fixed on the end side where the flange 5 of the cylindrical capacitor 1 is not formed. This is what I did. In this example,
The structure is such that the distance between the collar 5 and the metal eyelet terminal 10 almost matches the thickness of the substrate 6. In FIG. 6, flanges 5, 5 are formed at both ends of the cylindrical capacitor 1, and the spacing between the flanges 5, 5 is configured to approximately match the thickness of the substrate 6.

As is clear from each of these examples, the cylindrical capacitor 1 of the present invention sandwiches the substrate 6 between the protrusions formed by the metal eyelet terminals 4, 10 and the flanges 5, 5 formed on the outer peripheral surface of the cylindrical capacitor 1. The structure is such that the shaped capacitor 1 can be held well on the board 6 until it is soldered to the board 6.

Next, a specific example of actually attaching the above-described cylindrical capacitor of the present invention to a substrate will be described.

The through hole 7 formed in the substrate is connected to the cylindrical capacitor 1.
It is preferable to form the shape as shown in FIGS. 7 and 8 so that it can be held by the protrusions 4, 10, and 5. The one shown in FIG. 7 is a slit-shaped one extending inward from one end of the substrate 6, and its width is the same as that of the cylindrical capacitor 1 located between each protrusion 4, 10, 5.
The diameter is approximately the same as that of the Therefore, when attaching the cylindrical capacitor 1 to this, from the open end of the slit-like through hole 7, the protrusions 5 and 10 of the cylindrical capacitor 1 are positioned on the upper and lower surfaces of the substrate 6, that is, both protrusions are The cylindrical capacitor 1 may be inserted so that the substrate 6 is sandwiched between the parts 5 and 10 and held at a predetermined position. The one shown in Figure 8 is
The substrate 6 is provided with a through hole 7 in which a large diameter portion 7a and a small diameter portion 7b are connected. The large diameter portion 7a is larger than the diameter of the protrusion 10 of the cylindrical capacitor 1, and the small diameter portion 7b is smaller than the diameter of the protrusion 10 of the cylindrical capacitor 1, and is located between the protrusions 5 and 10 of the cylindrical capacitor 1. The diameter is larger than the diameter of the part located at. Therefore, when attaching the cylindrical capacitor 1 to the substrate 6, first attach the protrusion 1.
Only the 0 side is inserted into the large diameter part 7a of the through hole 7, and then, in this state, the cylindrical capacitor 1 is moved to the small diameter part 7b, and the board 6 is held between the protrusions 5 and 10. Bye.

Then, the cylindrical capacitor 1 held on the substrate 6 may be fixed to the substrate 6 with solder (not shown).

Note that the drawings are for embodying the present invention, and there is no hindrance to making various design changes without departing from the spirit of the present invention. In particular, the shape and structure of the cylindrical capacitor are arbitrary, and for example, a through terminal (not shown) can be electrically conductively fixed to the inner surface electrode 2 to form a through capacitor. Further, the shape of each protrusion is not limited to that shown in the drawings, and for example, the tip of each protrusion may be separated into a plurality of pieces. Furthermore, if necessary, the through hole formed in the substrate may be made into an elongated shape, and a plurality of cylindrical capacitors may be held and fixed in line in this through hole. In this case, if the protruding parts (metal eyelet terminals) of each cylindrical capacitor are made into a square shape and placed side by side with one end side touching each other, the positioning of each cylindrical capacitor will be even better. Moreover, as a result, the protruding portions (metal eyelet terminals) are connected and act to cover the through hole, so that a shielding effect can be obtained, which is very convenient. Further, the protruding portion may be formed in three or more layers, and in this way, it is possible to adapt to changes in the thickness of the substrate.

As described above, in the present invention, by providing a protrusion on the outer peripheral surface of the cylindrical capacitor that can hold and hold the board, even if the board is tilted or vibration is applied during handling, the cylindrical capacitor The capacitor does not easily fall off, and subsequent solder fixation can be performed stably and well. Furthermore, since the present invention has a configuration in which the cylindrical capacitor can be held on the substrate, there is no need for any special holding jig as in the prior art, and the process can be significantly simplified. Furthermore, in the present invention, since both protrusions of the cylindrical capacitor can be brought into contact with the board, the contact area with the board can be increased, and even when the board is heated during soldering and the cylindrical capacitor is preheated by conduction, This has many advantages, such as good preheating, no rapid heating of the cylindrical capacitor, and no cracking even when soldered.

[Brief explanation of drawings]

Figures 1 and 2 are side sectional views of a conventional cylindrical capacitor, Figures 3 to 6 are side sectional views showing examples of the shape of the cylindrical capacitor of the present invention, and Figures 7 and 8 are side sectional views of a conventional cylindrical capacitor. FIG. 2 is a perspective view showing an example of the shape of a substrate to which a cylindrical capacitor is attached. 1... Cylindrical capacitor, 4, 10, 5... Protrusion, 6... Substrate, 7... Through hole.

Claims (1)

[Claims] 1. An inner surface electrode and an outer surface electrode are provided on the inner peripheral surface and the outer peripheral surface, respectively, and at least one pair of protrusions projecting outward are formed on the outer peripheral surface at a constant interval from each other in the length direction. A cylindrical capacitor.