JPH039321Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] This invention relates to an electrolytic capacitor mounted on a so-called face bonding substrate, which does not have a through hole through which a lead wire of an electronic component is inserted.

[Conventional technology]

2. Description of the Related Art In recent years, due to demands for smaller and lighter electronic devices and for simpler and faster manufacturing processes, there has been a demand for leadless electrolytic capacitors mounted on so-called face bonding substrates.

As shown in FIG. 2, a conventional leadless electrolytic capacitor is manufactured by molding a capacitor element 1 impregnated with an electrolytic solution with a synthetic resin 7 or the like.
The lead wire 4 and the lead frame 6 are electrically connected, and the lead frame 6 is bent along the surface of the outer case to form a lead portion.

[The problem that the idea aims to solve]

In the case of leadless electrolytic capacitors with this structure, the structure of conventional electrolytic capacitors has to be significantly modified, and the heat generated during molding has a significant negative effect on the electrical characteristics of the capacitor element. Ta.

Furthermore, since it is difficult to join the lead frame and the synthetic resin, there is a risk that the electrolyte inside may leak to the outside.

The purpose of this invention is to provide a leadless electrolytic capacitor without changing the structure of conventional electrolytic capacitors.

[Means to solve the problem]

This idea involves forming a protrusion of an insulating sheathing member made of heat-shrinkable synthetic resin and tightly attached to the exterior case on the end face side from which the lead wire for drawing out the electrodes is drawn out, and also forming a protrusion on the end face of the insulating sheathing member that is in close contact with the exterior case. The present invention is characterized in that a portion of the lead wire for drawing out the electrodes forms a substantially flat surface on the end face of the protrusion of the insulating exterior member.

[Effect]

In this invention, as shown in the drawing, the lower side of the electrolytic capacitor body is covered with an insulating exterior member made of heat-shrinkable synthetic resin, the so-called sleeve 5.
It is in close contact with the outer case 2 due to heat treatment. The lead wire 4 led out from the capacitor element 1 is bent along the end surface of the sealing body 3 and forms a substantially flat surface together with the sleeve 5, allowing the electrolytic capacitor body to stand on its own and to be surface mounted on a printed circuit board, etc. become able to.

〔Example〕

This invention will be explained below according to the drawings.

The electrolytic capacitor body is as shown in Figure 1.
A capacitor element 1 is housed in an exterior case 2 made of aluminum or the like, and the opening of the exterior case 2 is sealed with a sealing body 3 made of elastic rubber or the like. The lead wire 4 led out from the end face of the capacitor element 1 penetrates the sealing body 3 and projects from the end face of the sealing body 3. The sleeve 5, which is an insulating exterior member made of a heat-shrinkable synthetic resin, is made of polyolefin, vinyl chloride, or polyester, which has a higher ratio of lateral shrinkage to heat shrinkage. In this embodiment, the sleeve 5 is made of vinyl chloride. The sleeve 5 is heat-treated after being coated on the outer case 2, and is brought into close contact with the outer case 2. Moreover, one end thereof is made to protrude from the end face of the electrolytic capacitor main body.

On the other hand, the lead wire 4 protruding from the end surface of the sealing body 3 has a flat tip and is formed at a substantially right angle toward the peripheral edge. Furthermore, the tip of the flat lead wire 4 is in contact with the end surface of the protrusion of the insulating exterior member 5.

In this embodiment, the tip of the lead wire 4 is formed into a substantially right-angled shape, but any forming process will deviate from this idea as long as it forms a substantially flat surface at the end surface with the sleeve 5. isn't it.

Further, the sleeve 5 may cover the entire side surface of the outer case 2.

[Effect of idea]

As described above, this invention has a protrusion of an insulating exterior member made of heat-shrinkable synthetic resin and tightly attached to the exterior case on the end face side from which the lead wire for drawing out the electrode is drawn out, and a Since the end face of the electrolytic capacitor and a part of the electrode lead wire form a substantially flat surface on the end face of the protruding part of the insulating exterior member, the electrolytic capacitor can stand on its own. Therefore, it can also be mounted on a face bonding board.

In addition, in this invention, the outer case is covered with a heat-shrinkable insulating outer member, which is heat-treated and adhered to the outer surface of the outer case, making it possible to change the structure and electrical characteristics of conventional electrolytic capacitors. Therefore, it is possible to provide an electrolytic capacitor compatible with a face bonding board, which is easy to manufacture, and the number of parts, manufacturing cost, etc. do not increase.

In addition, when the electrolytic capacitor body end face is mounted on a printed circuit board, it is placed apart from the printed circuit board, so it is less affected by heat from reflow processing, etc., and therefore affects the electrical characteristics of the capacitor element. does not affect

Furthermore, if a polarity display is printed on the insulating exterior member in advance, the polarity can be easily determined.

In summary, this invention is a useful invention that provides a leadless electrolytic capacitor compatible with a face bonding substrate without making any changes to the structure of conventional electrolytic capacitors.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing the structure of an electrolytic capacitor according to this invention, and FIG. 2 is a sectional view showing a conventional leadless electrolytic capacitor. 1...Capacitor element, 2...Exterior case, 3
... Sealing body, 4 ... Lead wire, 5 ... Insulating exterior member (sleeve), 6 ... Lead frame, 7 ...
Synthetic resin.

Claims (1)

[Scope of Claim for Utility Model Registration] (1) A protrusion of an insulating exterior member made of heat-shrinkable synthetic resin and tightly attached to the exterior case is formed on the end face side from which the electrode lead wire is led out, and an insulating An electrolytic capacitor characterized in that an end face of a protrusion of an exterior member and a portion of an electrode lead wire form a substantially flat surface. (2) The electrolytic capacitor according to claim 1, wherein the insulating exterior member is made of one of polyolefin, polyester, and vinyl chloride.