JPH0236266Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a capacitor that can be mounted on a circuit board etc. using an external terminal while maintaining a distance from the board. This invention relates to a capacitor with improved shape and improved heat resistance during soldering.

(b) Prior Art Recently, with the miniaturization of electronic devices, capacitors mounted in these devices have come to be widely used. However, in order to miniaturize the capacitors mentioned above, their exteriors have become thin, and when soldering is done while the capacitors are in close contact with the circuit boards of electronic devices, the parts that are in close contact with the circuit boards may be soldered. Heat is easily conducted to the internal capacitor element through the exterior, and there is a risk that electrical characteristics and reliability may be impaired. Therefore, as a countermeasure to this problem, a capacitor has been proposed in which the shape of the external terminal is devised and the capacitor can be mounted while maintaining a distance from the circuit board. That is, as shown in FIG. 4, in the capacitor 1, the external terminal 2 is led out from the end face of the sheath 3 that covers the capacitor element (not shown), and the external terminal 2 is bent downward along the end face of the sheath 3. It has a unique structure. The external terminal 2 has a wide part 5 formed from the connecting part with the capacitor element to the middle part, and the tip part 4 is formed into a thin pin shape, and the lower end of the wide part 5 and the tip part 4 are connected to the outer casing 3. It is arranged to protrude downward from the bottom surface.

When the capacitor 1 is mounted on the circuit board 8, the pin-shaped tip 4 of the external terminal 2 is inserted into the board hole 8a.
The lower end of the wide part 5 contacts the board 8 and is soldered while maintaining a distance between the sheath 3 and the board 8, so that the conduction is conducted to the internal capacitor element through the sheath 3. This can reduce the amount of heat generated.

(c) Problems to be solved by the invention However, in the conventional capacitor 1 described above, although the heat conduction through the exterior 3 is reduced,
As shown in FIG. 5, since the entire lower end of the wide part 5 of the external terminal 2 comes into contact with the circuit board 8, the melted solder 1
A large amount of 0 creeps up to the external terminal 2, and this large amount of heat from the large contact area with the solder 10 and the board 8 is conducted through the external terminal 2 and reaches the internal capacitor element, reducing the heat resistance during soldering. There is a problem that cannot be sufficiently improved.

This invention was devised in view of the above points,
The purpose is to provide a capacitor with sufficient heat resistance during soldering and high electrical characteristics and reliability by reducing the amount of heat that is conducted through the exterior and external terminals and reaches the internal capacitor element. shall be.

(d) Means for solving the problem The above objectives are to maintain the distance between the exterior and the board and to reduce the contact area of the external terminals with the board when mounting the capacitor on the circuit board. Therefore, the capacitor of the present invention provides an exterior covering to the capacitor element, leads out an external terminal from this, and forms a wide part wider than the tip of the external terminal. Further, in the capacitor in which the wide lower ends and tip portions of the external terminals are arranged so as to protrude from the exterior bottom surface, a notch is formed in the wide lower ends. Furthermore, when the external terminal is formed with a notch extending from a portion buried in the exterior to a portion exposed to the outside of the exterior, heat resistance is further improved.

(e) Effect When the capacitor of the present invention is mounted on a circuit board by soldering, the tip of the external terminal is inserted into the board hole, and the wide lower end contacts the board, causing a gap between the exterior and the board. The notch formed at the wide lower end of the external terminal reduces the contact area between the board and the external terminal and prevents solder from creeping up to the external terminal.

(f) Embodiment An embodiment of the present invention will be described below based on the drawings.

FIG. 1 is a schematic perspective view of a capacitor according to an embodiment of the present invention, and in the figure, a capacitor 1 is
For example, after laminating and winding a metalized film such as a metalized polyester film, it is flattened to form a capacitor element (not shown), and plate-shaped external terminals 2 are connected to both end faces of the capacitor element. The external terminal 2 is led out from both end faces of the outer case and is bent downward along the end face of the outer case 3.

The external terminal 2 is made of a metal plate of about 0.25 mm, and has a wide part 5 that is wider than the tip 4 from the connection part with the capacitor element to the middle part, and has a rectangular shape at the lower end of the wide part 5. A shaped notch 6 is bored, and the tip 4 is inserted into the board hole 8 of the circuit board 8.
The lower end of the wide portion 5 and the tip portion 4 are arranged so as to protrude downward from the bottom surface of the outer sheath 3. Further, the external terminal 2 has a wide part 5 from the part buried in the exterior 3.
A notch 7 consisting of a through hole is formed above the lower end of the external terminal 2 to prevent it from coming off from the exterior 3 when an excessive external force is applied to the external terminal 2, and to prevent the external terminal tip 4 from coming off from the exterior 3.
In addition, heat conduction from the lower end of the wide portion 5 is reduced.

However, when soldering the capacitor 1 of the present invention to the circuit board 8, if the tip 4 of the external terminal 2 is inserted into the board hole 8a as shown in FIG. 5 bottom end is board 8
A gap 9 is created between the outer casing 3 and the substrate 8 by contacting the outer casing 3 and the substrate 8 . Further, in this case, due to the notch 6 formed at the lower end of the wide part 5 of the external terminal 2, the contact area of the external terminal 2 with the board 8 is extremely small, so that when soldering, The amount of molten solder 10 creeping up is reduced. Furthermore, the wide part 4 of the external terminal 2
Due to the notch 7 formed above the lower end, the area of the external terminal 2 extending from the lower end of the wide part 4 to the inside of the exterior 3 is reduced.

Note that the notch 6 at the lower end of the wide part 5 of the external terminal 2 is
As mentioned above, in addition to the rectangular shape with both ends of the lower end remaining, the semicircular shape as shown in Figure 3A, and the one with a hole in the middle of the lower end as shown in Figure 3B. The shape and formation position can be arbitrarily selected as long as the area of the lower end of the wide portion 5 of the external terminal 2 can be reduced.

(g) Effect of the invention As detailed above, the capacitor of the invention has the lower end of the wide part formed on the external terminal protruding from the bottom of the exterior case and is placed below, so that it is easy to install the capacitor on the circuit board. A gap is maintained between the sheath and the board, reducing the amount of heat conducted from the board through the sheath into the capacitor, and a notch formed at the wide lower end of the external terminal allows the external terminal to Since the contact area with the board is small, the amount of solder creeping up to the external terminal during soldering is reduced, and the amount of heat that is conducted from the board and solder through the external terminal and reaches the inside of the capacitor is reduced.
Therefore, the amount of heat reaching the internal capacitor element is extremely small and its influence is small, resulting in a capacitor with good electrical characteristics and high reliability.

[Brief explanation of drawings]

Figures 1 and 2 show an embodiment of the present invention, with Figure 1 being a schematic perspective view, Figure 2 being a side view showing the state in which it is attached to a board, and Figures 3A and 3B. 4 is a side view of another embodiment of the present invention, and FIGS. 4 and 5 are a schematic perspective view and a side view of the conventional example, respectively, showing the state in which it is mounted on a board. DESCRIPTION OF SYMBOLS 1... Capacitor, 2... External terminal, 3... Exterior, 4... Tip, 5... Wide part, 6... Notch, 7... Notch.

Claims (1)

[Claims for Utility Model Registration] (1) A capacitor element is coated with an exterior, from which an external terminal is led out, and a wide part wider than the tip of the external terminal is formed, and 1. A capacitor in which a wide lower end and a leading end are arranged so as to protrude from the bottom surface of the exterior case, wherein a notch is formed in the wide lower end. (2) The external terminal is characterized in that a notch is formed from the part buried in the exterior to the part exposed to the outside of the exterior. capacitor.