JPH07263284A - Electronic component - Google Patents

Abstract

PURPOSE:To obtain an electronic component which has the total length of a lead terminal elongated to enhance heat-dissipating property in a soldering operation by a method wherein the lead terminal protrudes from a position near the surface of a resin molded part at a taper part and is guided downwards so as to be along the tape part and the edge of the molded part. CONSTITUTION:A capacitor element 1, an anode-side lead terminal 2 and cathode-side lead terminal 3 are packaged in such a way that they protrude from positions which are comparatively close to the surface 4c at taper parts 4a', 4b' from halfway parts of edges 4a, 4b of a resin molded part 4 toward the upper part over the surface 4c of the resin molded part 4. The lead terminals 2, 3 which protrude from the taper parts 4a', 4b' are extended along the taper parts 4a', 4b' and the edges 4a, 4b, and they are bent toward the inside at the bottom face of the resin molded part. Consequently, the total length of the lead terminals can be elongated, and the heat of molten solder or the like in a soldering and mounting operation can be dissipated by the lead terminals.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin mold type electronic component, and more particularly to a structure for assembling a resin mold type electronic component such as a solid electrolytic capacitor, a diode, a transistor, etc., whose characteristics are easily affected by heat.

[0002]

2. Description of the Related Art Conventionally, an electronic component of this type, for example, a solid electrolytic capacitor, is shown in FIGS. 5 (a) and 5 (b).
In the capacitor element 11, the anode rod 11b protruding from the element body 11a provided with the cathode layer on its surface is connected to the left and right lead terminals 12, 1 made of a metal plate.
3 is fixed to the lead terminal 12 on the anode side, while the element body 11b is connected to the lead terminal 13 on the cathode side. The external lead terminals 12a and 13a of the resin molds 12 and 13 are on both left and right end surfaces 1 of the resin mold portion 14.
The external lead terminals 12a and 13a are packaged so as to protrude from the middle of the resin mold portions 14a and 14b or to protrude from the bottom surface of the resin mold portion 14 (not shown).

[0003]

However, in the above-mentioned conventional solid electrolytic capacitor, the lead terminal 1 is used.
Since the external lead terminals 12a and 13a in 2 and 13 are efficiently arranged so as to project from the middle of the left and right end surfaces 14a and 14b of the resin mold portion 14 or the bottom surface of the resin mold portion 14, respectively. In addition, the length of the lead terminal is relatively short, and the external lead terminal portion is also short. As described above, in the conventional resin-molded electronic component, the lead terminal is short, and the heat during soldering is easily transferred to the electronic element such as the capacitor element 11 via the lead terminal depending on the mounting conditions when mounting on the board. Further, since the external lead terminal is short, when the electronic element such as the capacitor element 11 self-heats due to a ripple current or the like depending on the usage conditions, it is difficult for the heat to be dissipated from the electronic component. It was not always sufficient to deal with the problem of heat stress on electronic devices.

By the way, the resin mold type solid electrolytic capacitor, the diode and the like are polar parts having two lead terminals, and when the anode side and the cathode side are mounted in opposite directions, the element is broken or the A failure will occur in the applied electric circuit. Therefore, in a conventional solid electrolytic capacitor, diode, or the like, a slit hole is provided in either one of the two lead terminals so as to be left-right asymmetrical, or the upper surface of the resin mold portion is close to the anode side or the cathode side. The polarity can be identified by providing a polarity mark on the part, but it is never too efficient to provide a slit on the lead terminal or to provide a polarity mark on the resin mold part only for polarity determination. I couldn't say that.

It is an object of the present invention to improve the heat dissipation of a resin mold type electronic part by reducing the thermal effect such as thermal stress on the electronic element and further improve the reliability of the electronic part. And

[0006]

The present invention has been made to achieve the above object and relates to the following electronic parts. A taper portion is provided on the end surface of the resin mold portion so as to narrow from the middle of the end surface to the upper surface of the resin mold portion and upwardly narrow. An electronic component, characterized in that it protrudes from a position relatively close to the upper surface of the portion and is led out downward along the taper portion and the end surface of the resin mold portion. The electronic component is a polar electronic component having two opposing lead terminals, and only one of the two lead terminals projects from a taper portion provided in the resin mold portion. . The electronic component according to the above or, wherein at least one lead terminal has a corrugated plate-shaped portion.

[0007]

In the electronic component of the present invention, the lead terminal projects from a relatively upper portion of the resin mold portion,
Since the lead terminals are extended to the bottom, the lead terminals are long. Therefore,
When mounted on a mounting substrate such as a printed circuit board by soldering, the amount of heat of the molten solder or the like is transmitted through the lead terminals to the electronic element is reduced. In addition, since the lead terminal becomes long, the inductance increases as the length increases, and the electronic element is less likely to be damaged by an overcurrent such as an inrush current.

Further, in the electronic component of the present invention, the lead terminal is projected from the taper portion provided above the end surface of the resin mold portion and led out downward, so that the lead protruding from the resin mold portion is formed. The exposed area of the terminal becomes wider, and when soldered to the mounting board, the lead terminal of the portion along the taper portion of the resin mold portion can be mounted without being in contact with the solder. Functions as a heat dissipation plate, and the heat dissipation of electronic components is further improved. Therefore, even if the electronic element self-heats, the heat is effectively dissipated.

Further, in the case where the electronic component of the present invention is a polar two-terminal electronic component, a taper portion is provided on the end surface of the resin mold portion on one terminal side so that the lead terminal projects from the resin mold portion. If the length is made longer, the two terminals become asymmetric, so that it is possible to improve the heat dissipation and to easily determine the polarity. Also,
When the corrugated plate portion is provided on the lead terminal, the surface area of the lead terminal becomes larger, so that the heat dissipation is further improved, and the distance between the lead terminals becomes longer, so that the amount of heat conduction to the electronic element can be further reduced. .

As described above, the electronic component of the present invention is not easily affected by heat and has extremely high reliability.

[0011]

EXAMPLES The features of the present invention will be described in more detail below by showing examples in which the present invention is applied to a solid electrolytic capacitor, but the present invention is not limited thereto. In the solid electrolytic capacitor of the first embodiment, as shown in FIGS. 1 (a) and 1 (b), in the capacitor element 1, the anode rod 1b protruding from the element body 1a having the cathode layer provided on the surface thereof is opposed to the anode rod 1b. Of the pair of anode side and cathode side lead terminals 2 and 3 is fixed to one end of the anode side lead terminal 2, while the element body 1a is attached to one end side 3a of the cathode side lead terminal 3. Connecting. At this time, the lead terminals 2 and 3 on the anode side and the cathode side are bent upward.

Then, the capacitor element 1 and the lead terminals 2 and 3 on the anode side and the cathode side are connected to the resin mold portion 4, and the lead terminals 2 and 3 on the anode side and the cathode side are respectively connected to the resin mold portion 4. Of the resin mold portion 4 provided in the taper portions 4a ', 4b' extending from the middle of the end surfaces 4a, 4b to the upper surface 4c of the resin mold portion 4 and extending upward. Is packaged so as to project from a position relatively close to the upper surface 4c. The lead terminals 2 and 3 protruding from the taper portions 4a ′ and 4b ′ have the taper portions 4a ′ and 4
It extends along b'and the end faces 4a, 4b, and is bent inward at the bottom surface of the resin mold portion.

As shown in FIG. 2, when the solid electrolytic capacitor of the first embodiment constructed as described above is mounted on the printed circuit board B with the solder A, the solder A is the end surface 4a of the resin mold portion 4. , 4b and the lead terminals 2, 3 in the portions along the bottom surface 4d so that the solder A does not adhere to the lead terminals 2, 3 in the portions along the tapered portions 4a ', 4b'. . Therefore, the lead terminals 2, which are not attached to the solder A, are located along the tapered portions 4a ′, 4b ′.
No. 3 has a high heat dissipation effect.

In the first embodiment, both lead terminals 2,
3 is bent inward at the bottom surface 4d of the resin mold portion 4. However, it goes without saying that both lead terminals 2 and 3 are connected to the bottom surface 4d of the resin mold portion 4 in the present invention.
May be bent outward at. Next, a second embodiment is shown in FIGS. 3 (a) and 3 (b). The solid electrolytic capacitor of this example is different from the solid electrolytic capacitor of the first example except that the lead terminal on the anode side is bent downward from the middle of one end surface of the resin mold portion as in the conventional case. The configuration is similar to that of the first embodiment.
That is, the anode-side lead terminal 5 protruding from the anode-side end surface 7a of the resin mold portion 7 is led out downward from the middle of the end surface 7a, and the tip portion of the anode-side lead terminal 5 is The bottom surface 7d of the resin mold portion 7 is bent inward. On the other hand, the cathode-side end surface 7b of the resin mold portion 7 is provided with a taper portion 7b 'across the upper surface 7c of the resin mold portion 7 so that the resin mold portion 4 becomes narrower upward. The lead terminal 6 on the cathode side projects from the tapered portion 7b ′ at a position relatively close to the upper surface 7c of the resin mold portion 7, is led out along the tapered portion 7b ′ and the end surface 7b, and the lead on the cathode side is formed. The tip portion of the terminal 6 is bent inward at the bottom surface 7d of the resin mold portion 7.

In the solid electrolytic capacitor of the second embodiment, only the lead terminal 6 on the cathode side is provided long, but in the present invention, the lead terminal 5 on the anode side may be provided long. Good. Next, a third embodiment is shown in FIG.
In this embodiment, both lead terminals 2 and 3 in the solid electrolytic capacitor of the first embodiment are provided with corrugated plate portions. That is, a part or all of the lead terminals 8 and 9 on the anode side and the cathode side are formed in a corrugated plate shape, and the surface areas of these lead terminals 8 and 9 are increased and the length is increased. When all the external lead portions projecting from the resin mold portion 4 of the lead terminals 8 and 9 are formed in a corrugated plate shape, the heat dissipation from the lead terminals 8 and 9 can be improved, and the soldering strength can also be improved. In the present invention, both lead terminals 8 and 9 are
Only one of them may be shaped like a corrugated plate, and in this case, it can be used as a polarity determining means in a polar component such as a solid electrolytic capacitor. Further, the lead terminal 6 on the cathode side in the solid electrolytic capacitor of the second embodiment described above.
May be corrugated.

The embodiments in which the present invention is applied to a solid electrolytic capacitor have been described above, but the present invention can be widely applied not only to diodes but also to electronic parts having three or more terminals such as transistors. Is.

[Brief description of drawings]

FIG. 1 is a sectional view (a) and a perspective view (b) showing a solid electrolytic capacitor of a first embodiment.

FIG. 2 is a side view illustrating a state when the solid electrolytic capacitor according to the first embodiment is mounted on a printed board.

3 (a) is a sectional view and FIG. 3 (b) is a perspective view showing a solid electrolytic capacitor according to a second embodiment.

FIG. 4 is a perspective view showing a solid electrolytic capacitor of a third embodiment.

5 (a) is a sectional view and FIG. 5 (b) is a perspective view showing a conventional solid electrolytic capacitor.

[Explanation of reference numerals] 1 capacitor element 1a element body 1b anode rod 2,3,5,6,8,9 lead terminal 4,7 resin mold part 4a, 4b, 7a, 7b end face 4a ', 4b' in the resin mold part , 7b 'Tapered part in resin mold part A Solder B Printed circuit board

Claims (3)

[Claims] 1. A taper portion is provided on an end face of the resin mold portion so as to become narrower from the middle of the end face to the upper surface of the resin mold portion and upwardly narrow, and the lead terminal is provided with the taper portion. The electronic component is characterized in that it protrudes from a position relatively close to the upper surface of the resin mold portion in the portion and is led out downward along the tapered portion and the end surface of the resin mold portion. 2. The electronic component is a polar electronic component having two opposing lead terminals, and only one lead terminal of the two lead terminals projects from a taper portion provided in the resin mold portion. Item 1. The electronic component according to Item 1. 3. The electronic component according to claim 1, wherein at least one lead terminal has a corrugated plate portion.