JP2000277399A - Manufacturing method of chip capacitor and forming tool for lead wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To smoothly and properly carry out crushing of a lead wire at low costs without generating excessive stress on the lead wire by using a tool having a simple constitution. SOLUTION: In this manufacturing method for a leading base from a chip capacitor body 20 of a pair of lead wires 21a and 21b, a tool 22 that retains the leading base and is used as an inner die, and a pair of pressure-welding tools 24 and 25 that are used as a pair of outer dies that are arranged opposed toward the tool, performs advance/retraction movement for the lead wire being retained by the tool, allows the leading base to be subjected to crushing are provided. Also, in the tool used as the inner die, two formation processes that freely retain one lead wire and the other, and allow the leading base of one lead wire and the other to be subjected to crushing by one pressure-welding tool 24 and the other 25, respectively, are conducted successively.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of manufacturing a chip-type capacitor, and more particularly to a method of manufacturing a chip-type capacitor capable of smoothly forming a connecting end portion of a lead wire in the chip-type capacitor. The present invention relates to a manufacturing method and a jig for forming a lead wire used in the manufacturing method.

[0002]

2. Description of the Related Art Conventionally, a chip-type aluminum electrolytic capacitor has been known as a chip-type capacitor. This aluminum electrolytic capacitor has a lead-less configuration so that it is suitable for surface mounting on a printed circuit board or the like. Capacitors have been put to practical use.

[0003] Therefore, as a chip type capacitor of this type, an anode foil formed by roughening an aluminum foil and further forming a dielectric film by anodic oxidation, and a cathode foil formed by roughening the aluminum foil are separated by a separator. , And impregnated with a driving electrolyte to form a capacitor element,
The capacitor element is housed in a bottomed cylindrical metal case, and the open end is sealed using a sealing member having elasticity such as rubber to constitute an aluminum electrolytic capacitor, and a lead wire drawn from the aluminum electrolytic capacitor. Are electrically and mechanically connected to the terminals by a method such as welding, and the whole except for the terminals is coated with a molded resin to obtain a finished product.

[0004] The chip-type capacitor thus configured is provided with a mold resin exterior as described above in order to maintain solder heat resistance when mounted on the printed circuit board or the like. Therefore, when a mold resin exterior is implemented in this type of chip type capacitor, generally 100 ° C.
At a temperature of about 150 ° C., pressure is applied at a pressure of 10 kg / cm 2 for about 5 minutes. Electrolytic capacitors exposed to such harsh conditions cause the driving electrolyte to evaporate and the capacitance to rise. And the deterioration of characteristics such as an increase in tan δ.

Conventionally, however, as shown in FIG. 4, a through hole 16a is provided on the end face of the electrolytic capacitor 10 from which the lead wire 11 is drawn out so as to be in contact with the lead wire and can penetrate the lead wire. An insulating plate 16 is disposed on the outer surface of the insulating plate 16, and a concave portion 16b continuous with the through-hole 16a is provided on the outer surface of the insulating plate 16, and a tip end of the lead wire 11 penetrating the through-hole 16a is inserted into the concave portion 16b. A structure that is bent so as to fit is proposed (JP-A-60-245107).

However, when the lead wire of the electrolytic capacitor according to the above proposal is bent along an insulating plate, the lead wire is easily bent, and when the chip type capacitor is mounted on a printed circuit board or the like, the printed circuit board is printed. In order to increase the area of the lead wire facing the printed circuit board in order to improve the solderability to the lead wire, it is preferable that the lead wire is formed in a flat plate shape. For this reason, a part of the lead wire, that is, the lead base of the lead wire is crushed by using a pressure welding jig or the like.

Therefore, in a conventional manufacturing process of a chip-type capacitor in which such a lead wire is crushed, for example, as shown in FIG.
Lead wires 11a, 1a derived from one end face of
1b, the jig 12 as the inner mold is inserted, and the pressing jigs 13 and 14 as the outer mold are moved from both sides thereof,
By pressing the jig 12 and the pressing jigs 13 and 14 by the pressing force, a part of the two lead wires 11a and 11b is crushed at the same time.

[0008]

However, the thickness w of the jig 12 inserted between the lead wires 11a and 11b in the crushing of the lead wire of the conventional chip type electrolytic capacitor described above is limited to the lead wire 11a. , 11b with a slightly smaller width (w <p) than the pitch p. This is because the lead pitch p has a slight variation, so that it is necessary to make the thickness of the jig 12 smaller than the lead pitch to accommodate all capacitors. is there.

It is assumed that the jig 12 has the same width as the lead pitch p or the jig 12 is thicker than the lead pitch.
When the jig 12 is used, when the jig 12 is inserted between the lead wires, the jig rubs the surface of the lead wire, resulting in damage to the lead wire. Further, when the jig is thicker than the pitch of the lead wires (w> p), the more the jig is pushed toward the base of the lead wire, the wider the pitch of the lead wire is. There is a drawback of applying mechanical stress to the inside.

Therefore, as in the prior art, a jig thinner than the pitch between the lead wires is inserted between the lead wires, and the pressure welding jig is moved from both ends thereof to simultaneously crush the two lead wires. Therefore, the stress that the lead wire is pulled inward from the pitch width is applied. This stress is transmitted to the inside of the capacitor, and not only adversely affects the capacitor, but also exerts excessive mechanical stress on the lead base of the lead wire.

The inventor of the present invention has made intensive studies and studies, and as a result, squeezes the lead-out bases of a pair of lead wires led out from a sealing portion formed on one end face of the chip-type capacitor body. In the manufacture of a chip capacitor that is formed by bending and forming a connection end portion on an insulating plate abutted on the lead wire lead-out end face of the chip capacitor body, the pair of lead wires from the chip capacitor body is With respect to the lead-out base, a jig as an inner die holding the lead-out base, and a front-rearwardly-displaced movable member disposed to face the outside of the jig and moved forward and backward with respect to the lead wire held by the jig, and crushing the lead-out base. And a pair of press-fitting jigs as an outer mold for holding the other lead wire in a free state in the jig as the inner mold, and deriving a base of one lead wire by the one press-fitting jig. Press By setting to sequentially perform the forming step of crushing and the forming step of crushing the lead base of the other lead wire by holding the one lead wire in a free state and pressing the other lead wire by the other pressure welding jig, It has been found that smooth and proper crushing of the lead wire can be achieved without causing excessive stress to the lead wire.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to perform smooth and proper crushing of a lead wire at low cost by using a jig having a simple structure without causing excessive stress to the lead wire. An object of the present invention is to provide a method of manufacturing a chip-type capacitor which can be achieved and a jig for forming a lead wire used in the manufacturing method.

[0013]

In order to achieve the above object, a method for forming a lead wire of an electrolytic capacitor according to the present invention comprises a pair of lead wires led out from a sealing portion formed on one end surface of a chip type capacitor body. In contrast, in the method of manufacturing a chip-type capacitor, the connection base is formed by crushing the lead-out base and bending and forming the connection end on an insulating plate in contact with the lead-out lead end surface of the chip-type capacitor body. A jig as an inner die holding the pair of lead wires from the chip-type capacitor main body with respect to the lead-out portion from the chip-type capacitor main body, and a lead wire disposed opposite to the jig and held by the jig. A pair of press-fitting jigs as an outer die for moving forward and backward to crush the lead-out base portion, and in the jig as the inner die, the other lead wire is held in a free state and A forming step of crushing the lead-out base of one lead wire using a pressure welding jig, and then crushing the lead-out base of the other lead wire using the other pressure welding jig while holding one lead wire in a free state. And forming steps to be performed sequentially.

In this case, in the jig serving as the inner mold, a first forming step of holding the other lead wire in a free state and crushing the lead base of one lead wire by the one pressure welding jig. And a second molding step of inserting the lead bases of the two lead wires through an expansion guide to form a mutually expanded shape, and further holding one of the lead wires in a free state and using the other pressure welding jig. It is preferable that the third forming step of crushing and processing the lead base of the other lead wire be sequentially performed.

[0015] When the method for manufacturing a chip-type capacitor is performed, a jig as an inner mold for forming a lead wire is provided with one lead wire led out from the chip-type capacitor main body in the first forming step. And a first insertion hole for inserting the other lead wire in a substantially free state and performing a mutual sense of both the lead wires in the first molding step. A second insertion hole provided with an expansion guide at a central portion for forming and maintaining an appropriate expanded state, and the other lead wire is crushed by a pressure contact portion of the other pressure welding jig in a third molding step. A third insertion hole for processing and inserting one of the lead wires in a substantially free state may be provided.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an embodiment of a manufacturing method for crushing a lead wire in a chip type capacitor according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 and FIG. 2 show schematic structures of a jig and a pressure welding jig for crushing a lead wire of a chip type capacitor according to the present invention. In other words, the jig for crushing the lead wire of the pressure welding jig and the pressure welding jig in the present embodiment are a pair of lead wires 21a and 21b led out from the same end face of the chip type capacitor body 20.
On the other hand, a jig 22 as an inner die capable of sequentially performing the crushing process including three steps, and an outer die movably provided at both end portions of the jig 22 so as to be able to press and separate from each other. It is composed of a pair of pressure welding jigs 24 and 25.

However, the jig 22 as the inner die of the present embodiment moves the one lead wire 21a led out of the chip-type capacitor body 20 and the one pressure welding jig 24 in the first molding step. A first insertion hole 22a through which the press-contact portion 24a can be crushed and the other lead wire 21b can be inserted in a substantially free state is provided. Further, the jig 22 is used in the second molding step.
A second insertion hole 22b provided with an expansion guide 23 in the center is provided so as to form and hold an interval between the two lead wires 21a and 21b in an appropriate expanded state. And the jig 23
In the third molding step, the other lead 21
b, by moving the other pressing jig 25 to
a to perform the crushing process and one lead wire 2
3a, through which the first insertion hole 1a can be inserted in a substantially free state.
c.

As described above, in the present embodiment, on the jig 22 as the inner die, the chip-type capacitor main body 20 is moved from the first insertion hole 22a to the third insertion hole 22c. In the three-stage molding process, the chip-type capacitor body 20 can be smoothly achieved while sequentially moving the chip-type capacitor body 20 at a required pitch interval.

Next, the crushing of the lead wires 21a and 21b of the chip-type capacitor body 20 when the jig 22 and the press-welding jigs 24 and 25 having the above-described configurations are used will be described.

[0021]First molding process  At one end of the jig 22, the chip type capacitor body 20
Of one lead wire 21a derived from
While positioning it to face the tool 24, and
Lead wire 21b into the first insertion hole 22a, and
And keep it free. In this state, the pressure welding
The jig 24 is moved so that the press contact portion 24a is
With the required pressing force against the lead base of the lead wire 21a
A predetermined crushing process is performed by pressing.

[0022]Second molding process  Next, the chip type capacitor body 20 is connected to the jig 2.
2 along the longitudinal direction of the two lead wires 2
1a and 21b are inserted into the second insertion hole 22b. This place
In this case, the expansion guide provided inside the second insertion hole 22b
23, the lead wires 21a and 21b are mutually expanded.
Then, the gap is formed and held in an appropriate expanded state.

[0023]Third molding process  Thereafter, the chip-type capacitor body 20 is connected to the jig 2.
2 to the other end of the lead wire 21b.
Is positioned so as to face the other pressure welding jig 24.
At the same time, one lead wire 21a is inserted into the third insertion hole 22c.
Insert it and keep it almost free. In this state
Then, the pressing jig 25 is moved and the pressing portion 2 is moved.
5a with respect to the lead base of the other lead wire 21b.
A predetermined crushing process is performed by pressing with a necessary pressing force.

Therefore, in the present invention, the chip-shaped capacitors are sequentially and continuously supplied to the first to third molding steps to crush each lead wire continuously. Continuous production of such a chip-type capacitor can be smoothly achieved.

Then, in the chip type capacitor in which the crushing of the lead wire is completed, the lead wire on the tip side from the crushed portion is appropriately cut and removed, and as shown in FIG. The crushed tip of the lead wire led out from the hole 16a is bent so as to fit into the recess 16b provided on the outer surface thereof and continuing to the through hole 16a, so that a finished product can be obtained.

The preferred embodiment of the present invention has been described above. However, the present invention is not limited to the above-described embodiment, and for example, the second molding step may be omitted in the above-described embodiment.
Various design changes can be made without departing from the spirit of the present invention.

[0027]

As is apparent from the above-described embodiment, the method for manufacturing a chip-type capacitor according to the present invention is applied to a pair of lead wires led out from a sealing portion formed on one end surface of a chip-type capacitor body. A method for manufacturing a chip-type capacitor, wherein the connection base is formed by crushing the lead-out base and bending and forming the connection end on an insulating plate in contact with the lead-out lead end of the chip-type capacitor body. The jig as an inner die for holding the lead wire from the chip-type capacitor main body with respect to the lead-out portion of the chip-type capacitor body, and the reciprocating movement with respect to the lead wire held opposite to the jig and arranged outside the jig. To crush the lead-out base
A pair of press-fitting jigs as an outer mold is provided, and in the jig as the inner mold, the other lead wire is held in a free state and the lead-out base of one lead wire is crushed by the one press-fitting jig. By forming the forming step of processing and then the forming step of holding the one lead wire in a free state and crushing the lead base of the other lead wire with the other pressure welding jig, the lead forming step is sequentially performed. Smooth and appropriate crushing of the lead wire can be achieved without causing excessive stress on the wire.

In particular, according to the method for manufacturing a chip capacitor according to the present invention, a jig having a specific configuration is used,
Each lead wire is separately crushed at the required process interval, so that no sudden stress is applied to the lead wire, so that deterioration and breakage of the lead wire can be suppressed, and the inside of the capacitor can be suppressed. Thus, it is possible to easily manufacture a chip-type capacitor with stable quality by preventing the application of mechanical stress to the capacitor.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional side view showing one embodiment of a lead wire forming jig for performing a method of manufacturing a chip capacitor according to the present invention.

FIG. 2 is a schematic plan view of the lead wire forming jig shown in FIG.

FIG. 3 is a schematic side view of a conventional jig for forming a lead wire of a chip-type capacitor.

FIG. 4 is a cross-sectional front view of a main part of a conventional chip-type capacitor having a leadless configuration.

[Explanation of symbols]

 Reference Signs List 20 chip-type capacitor main body 21a, 21b lead wire 22 jig (inner die) 22a first insertion hole 22b second insertion hole 22c third insertion hole 23 expansion guide 24, 25 pressure welding jig (outer die) 24a , 25a

Claims (3)

[Claims] 1. A pair of lead wires led out from a sealing portion formed on one end face of a chip-type capacitor body, the lead-out bases of which are crushed and abutted against the lead wire lead-out end face of the chip-type capacitor body. A method for manufacturing a chip-type capacitor, which is formed by bending and forming a connection end portion on an insulating plate that has been formed, wherein an inner die for holding the pair of lead wires from the base of the chip-type capacitor body is held. And a pair of press-fitting jigs as outer molds for displacing and retracting a lead wire held by the jig and squeezing a lead-out base of the jig. In the jig as the inner mold, a molding step of holding the other lead wire in a free state and crushing the lead base of one lead wire by the one pressure welding jig; Lee Method for manufacturing a chip type capacitor, which comprises carrying out the holding of the line in a free state the other pressing jig and molding step of processing crushed derivation base of other lead successively. 2. A pair of lead wires led out from a sealing portion formed on one end face of a chip type capacitor body, and the lead-out base portions thereof are crushed and abut on the lead wire leading end face of the chip type capacitor body. A method for manufacturing a chip-type capacitor, which is formed by bending and forming a connection end portion on an insulating plate that has been formed, wherein an inner die for holding the pair of lead wires from the base of the chip-type capacitor body is held. And a pair of press-fitting jigs as outer molds for displacing and retracting a lead wire held by the jig and squeezing a lead-out base of the jig. In the jig as the inner mold, a first molding step of holding the other lead wire in a free state and crushing the lead base of one lead wire by the one pressure welding jig,
Next, a second forming step in which the lead bases of the two lead wires are inserted into the spreading guide to form a widening with each other, and one of the lead wires is held in a free state and the other is pressed by the other pressure welding jig. The third to crush the lead base of the lead wire
And a step of forming the chip-type capacitor in sequence. 3. A jig serving as an inner mold, wherein one lead wire led out of the chip-type capacitor main body in the first molding step is crushed by a press-contact portion of one press-contact jig, and the other lead is processed. A first insertion hole for inserting a wire in a substantially free state, and an expansion guide provided at a central portion for forming and holding a mutual sense of both lead wires in an appropriate expanded state in a first molding process. The second through hole and the third
In the forming step, the other lead wire is crushed by a pressure contact portion of the other pressure welding jig, and a third insertion hole for inserting the one lead wire in a substantially free state is provided. 3. A jig for forming a lead wire used in the method for manufacturing a chip-type capacitor according to claim 2.