JP3538693B2 - Manufacturing method of electronic component with insulated lead wire - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing an electronic component with an insulated lead, in which an insulating coating is formed so as to cover a predetermined length of the lead in the electronic component with a lead. The present invention relates to an improvement in a method of forming an insulating coating on a lead wire by a dipping method.

[0002]

2. Description of the Related Art FIG. 6 shows an electronic component 1 with lead wires which is of interest to the present invention. This electronic component 1
Is manufactured through the steps shown in FIG. The form of the electronic component 1 with lead wires shown in the drawing is, for example,
It is applied to thermistors, varistors, capacitors, oscillators and the like.

Referring to FIGS. 6 and 7, an electronic component 1 with lead wires includes, for example, a disk-shaped electronic component main body 2, and two opposing main surfaces of the electronic component main body 2 respectively have: Electrodes are formed. Each electrode has a lead wire 3
Are electrically connected by soldering or the like. A structure including the above-described components is shown in FIG. To cover the electronic component body 2 in this structure,
The insulating sheath 4 is formed. In order to form this insulating sheath 4, as shown in FIG. 7 (2), it is dipped in an uncured resin 5, and then, as shown in FIG. 7 (3), a structure including the electronic component body 2 is formed. After being lifted from the resin 5, the uncured resin 5 applied on the electronic component body 2 is cured by, for example, heat treatment.

[0004] The electronic component 1 with leads thus obtained is called a radial lead type electronic component because it has the leads 3 extending in the same direction and parallel to each other from the electronic component body 2. ing. When such an electronic component with leads 1 is mounted on a circuit board (not shown), the leads 3 are usually inserted into holes provided in the circuit board, and in that state, the leads 3 are mounted on the circuit board. Is soldered to the conductive land formed on the substrate. In this case, lead 3
Is not so long, so lead 3
Unnecessary parts are cut off and removed.

On the other hand, in a specific situation, a part of the lead wire 3 may be used as a part of the wiring. In this case, the lead wire 3 is left in a relatively long state, and the lead wire 3 is routed along the circuit board or other electronic components and then soldered to a predetermined position. Such a situation is often encountered, for example, when the electronic component 1 is a temperature detecting thermistor.

[0006] As described above, when the lead wire 3 is routed, a predetermined length of the lead wire 3 is used to avoid undesired electrical contact or interference with a circuit board or other electronic components. It is necessary to apply an insulating coating 6 as shown by imaginary lines in FIG. The insulating coating 6 is generally formed by a method as shown in FIG. That is, FIG.
As shown in (1), first, an uncured resin 7 to be an insulating coating 6 is prepared. As the resin 5 constituting the insulating sheath 4 on the electronic component body 2 described above, a resin having relatively high mechanical strength is used to secure the strength.
Must be made of a material that allows the lead wire 3 to be easily bent, so that the resin 7 for the insulating coating 6 needs to have flexibility.

Next, as shown in FIG. 8A, the electronic component 1 with a lead wire is dipped in the uncured resin 7 described above. At this time, the electronic component main body 2 side is directed downward, so that a predetermined length of the lead wire 3 is buried in the resin 7. Next, as shown in FIG. 8B, the resin 7 applied on the electronic component 1 with leads after being pulled up from the resin 7 is cured to form the insulating coating 6.

[0008]

However, the insulating coating 6 formed by the above-described method is not only on the required lead wire 3 but also on the insulating sheath 4 which covers the electronic component body 2 which is an unnecessary area. Is also formed. For this reason, the resin 7 for the insulating coating 6 is wasted and the unnecessary cost is increased accordingly.

Further, since the electronic component body 2 is covered not only by the insulating sheath 4 but also by the insulating coating 6, the thickness 8 of the portion covering the electronic component body 2 becomes considerably large. As a result, the space required for mounting the electronic component 1 with leads provided with the leads 3 having such an insulating coating 6 increases, which is not preferable. In addition, the variation in the liquid level of the uncured resin 7 when the electronic component 1 with lead wires is dipped affects the length 9 of the insulating coating 6. 9
However, there is also a problem that the variation is relatively large.

When the electronic component 1 with the lead wire is pulled out from the uncured resin 7, the lead wire 3 is oriented in the vertical direction. There is also a problem that the thickness of the obtained insulation coating 6 varies in the longitudinal direction of each lead wire 3. If the insulating sheath 4 and the insulating coating 6 may be made of the same resin, for example, in the step of FIG. By doing so, the insulating sheath 4 and the insulating coating 6 can be simultaneously formed, which is efficient. Further, according to this method, problems such as the waste of the resin 7 and the increase in the thickness 8 as described above are solved.

However, in practice, it is not practical to form the insulating sheath 4 and the insulating coating 6 with the same resin.
Because, as described above, a dipping resin that simultaneously satisfies the function of ensuring the strength required for the resin 5 constituting the insulating sheath 4 and the flexibility and flame retardancy required for the resin constituting the insulating coating 6 is as follows: It has not been developed yet.

It is an object of the present invention to provide a method of manufacturing an electronic component with an insulated lead wire that can solve the various problems described above.

[0013]

SUMMARY OF THE INVENTION The present invention provides a process for preparing an electronic component with a lead wire, comprising: an electronic component main body; a lead wire extending from the electronic component main body; and an insulating sheath covering the electronic component main body. The present invention is directed to a method for manufacturing an electronic component with an insulating-coated lead wire, comprising a step of forming an insulating coating so as to cover a predetermined length of the lead wire in the electronic component with a lead wire. In order to solve the technical problem, the following features are provided.

That is, in the manufacturing method according to the present invention,
A coating tank having an open upper surface is provided for storing an uncured resin to be an insulating coating and forming a bath of the resin. Then, in the step of forming the insulating coating described above,
(1) A lead wire such that a predetermined length of the lead wire is buried in an uncured resin, and one end of a portion where an insulating coating is to be formed is in contact with one side edge defining an opening of the coating tank. Positioning the electronic components with the paint tank.
(2) Then, at least one of the coating tank and the electronic component with a lead wire is inclined so that the other side edge opposite to the side where the one side edge is located is separated from the portion where the insulating coating is to be formed. Thereby removing the lead from the uncured resin bath in the coating tank in a horizontal or nearly horizontal position; and (3) then curing the resin applied on the lead to form an insulating coating. The forming is performed.

In the present invention, preferably, a notch having a size that can hold the uncured resin based on its surface tension is formed in the other side edge of the coating tank. In the step of positioning the electronic component with the lead wire with respect to the coating tank, the lead wire is located in the notch.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows a manufacturing apparatus 11 for carrying out a method for manufacturing an electronic component with an insulated lead wire according to an embodiment of the present invention. This device 11
Handles the electronic component 1 with leads obtained through the process shown in FIG. 7 described above. The lead 3 of the electronic component 1 with leads is insulated as shown by an imaginary line in FIG. The coating 6 is applied to manufacture an electronic component with an insulating coating lead wire.

Referring to FIG. 1, a manufacturing apparatus 11 includes a supply tank 12 for supplying an uncured resin 7 to be an insulating coating 6. The apparatus 11 further includes a coating tank 13 that receives the supply of the resin 7 from the supply tank 12. The coating tank 13 is provided so as to be movable in the vertical direction as shown by a double-headed arrow 14, whereby the coating tank 13 is positioned in the resin 7 in the supply tank 12 as shown by a broken line, and as shown by a solid line. And a state in which the resin 7 is located above the liquid level of the resin 7 in the supply tank 12.

FIG. 2 is a perspective view showing the positional relationship between the coating tank 13 and the electronic component 1 with lead wires when the coating tank 13 is at the upper position. The electronic component 1 with lead wires is held by a holder 15 made of, for example, a tape-shaped sheet member. The holder 15 holds a plurality of electronic components 1 with leads distributed in the longitudinal direction, and the plurality of electronic components 1 with leads are handled by the device 11 at the same time.

As described above, the electronic component with lead wire 1 held by the holder 15 is positioned with respect to the coating tank 13 by positioning the holder 15 on the positioning rail 18. At this time, each lead wire 3 extends horizontally or almost horizontally. The coating tank 13 includes a fixed plate 19 and a movable plate 20. The movable plate 20 has an L-shaped cross section including a bottom wall and a side wall, and is connected to a lower end of the fixed plate 19 via a shaft 21 at a tip end of the bottom wall. Accordingly, the movable plate 20 is rotatable as shown by an arrow 22 in FIG. 1, and by this rotation, as shown by an imaginary line, it can be tilted downward, for example, by about 45 degrees.

The coating tank 13 has an opening 23 on the upper surface. One side edge 24 defining the opening 23 is provided by the upper edge of the fixed plate 19, and the other side edge 25 is similarly provided by the upper edge of the side wall of the movable plate 29. As described above, the coating tank 13 is connected to the supply tank 12.
When the resin 7 is lifted up and takes an upper position, the uncured resin 7 supplied from the supply tank 12 is stored therein to form a bath of the resin 7. At this time, coating tank 1
The resin 7 in the edge portion 3 is applied to the edge portion 2 while exerting its surface tension.
The liquid surface slightly rises from 4 and 25.

Preferably, the other side edge portion 25 described above is used.
As shown in FIG. 2, a plurality of notches 26 are formed so as to be distributed in the longitudinal direction of the coating tank 13.
In FIG. 3, as shown by one notch 26, the notch 26 is selected to have a size capable of holding the resin 7 based on its surface tension. Further, the coating tank 13 can be reciprocated in its longitudinal direction as shown by a double-headed arrow 27 in FIG.

Using the apparatus 11 as described above, the resin 7 which becomes the insulating coating 6 is applied to the lead wire 3 of the electronic component 1 with the lead wire as shown in FIG. . First, the coating tank 13 moves upward from the supply tank 12 in a state where the electronic component with leads 1 before forming the insulating coating 6 is positioned by the positioning rail 18. As a result, as shown by the solid line in FIG.
The uncured resin 7 is stored in the resin 3, and a predetermined length of the lead wire 3 is buried in the resin 7.

At this time, as shown in FIG.
Is located within the notch 26, and the surface of the resin 7 held at the notch 26 with surface tension defines the end of the region of the lead wire 3 where the resin 7 is to be applied. Further, one end of a portion where the insulating coating 6 is to be formed, that is, in the illustrated embodiment, the end of the insulating sheath 4 on the electronic component body 2 on the side of the lead wire 3 contacts the above-described one side edge 24. State.

In this manner, the electronic component with lead wire 1
After being positioned with respect to the coating tank 13, as shown in FIG. 4, the movable plate 20 is moved around the shaft 21 so as to lower the other side edge 25, that is, the arrow 22.
Tilted in the direction. Accordingly, the uncured resin 7 existing around the lead wire 3 not only partially falls off the coating tank 13, but also has a plurality of surfaces on the movable plate 20 with respect to the resin 7. An arrow 28 extends along the longitudinal direction of the lead wire 3 as indicated by a two-dot chain line.
Move in the direction. The movable plate 20 is inclined to, for example, about 45 degrees.

In this manner, the lead 3 and the bath of the uncured resin 7 are separated while the resin 7 serving as the insulating coating 6 is adhered on each lead 3, and the uncured lead 7 is separated. It is taken out of the resin 7. In addition, the posture of the lead wire 3 at the time of this removal is horizontal or almost horizontal. From these facts, the extra resin 7 does not adhere to the lead wire 3 and the dripping of the resin 7 on the lead wire 3 can be prevented. The thickness of the insulating coating 6 can be made uniform or almost uniform in the longitudinal direction of the lead wire 3.

As described above, even after the lead wire 3 is taken out of the resin 7, the one side edge 24 of the opening 23 provided by the upper edge of the fixing plate 19 remains in contact with the insulating sheath 4 on the electronic component body 2. It remains in contact with the end. The uncured resin 7 exists in this contacted part. Next, the coating tank 13 is moved in the direction indicated by the arrow 29 in FIG. 5 so as to be submerged in the supply tank 12 again. Resin 7 (not shown in FIG. 5) present between the portions may hang down like a string. In order to prevent this, the coating tank 13 is reciprocated as indicated by the double-headed arrow 27 before or simultaneously with the movement in the direction of the arrow 29.

Next, the coating tank 13 is moved in the direction of the arrow 29, is sunk in the supply tank 12, and the movable plate 20 is returned to the original horizontal state. In addition, the coating tank 13
It is preferable to stir the uncured resin 7 in the supply tank 12 at any time when is not present in the supply tank 12. On the other hand, as described above, the resin 7 applied on each lead wire 3 is cured by, for example, heat treatment,
Thereby, as shown by the imaginary line in FIG. 6, the insulating coating 6 is formed on each lead wire 3. At this time, in order to obtain the insulating coating 6 having a more uniform thickness, it is preferable to keep the lead wire 3 as horizontal as possible until the resin 7 is cured.

Thereafter, the above steps are repeated. As described above, the present invention has been described with reference to the illustrated embodiments, but other embodiments are possible within the scope of the present invention. For example, in the illustrated embodiment, the resin 7 in the coating tank 13 is stored so as to swell from the edges 24 and 25 of the opening 23, but such swelling lifts the coating tank 13 from the supply tank 12. Sometimes formed naturally, it is not always necessary to form positively. In particular, as in the illustrated embodiment, the notch 26
Is formed, and when the lead wire 3 is positioned in the notch 26, the swelling of the resin 7 has little meaning.

In the illustrated embodiment, the resin 7 is supplied to the coating tank 13 by moving the coating tank 13 as indicated by a double-headed arrow 14 and pumping up the resin 7 in the supply tank 12. Alternatively, another method such as directly injecting the resin 7 into the coating tank 13 may be used. In addition, in the illustrated embodiment, the coating tank 13 includes the fixed plate 19 and the movable plate 20, but may have an integral structure as a whole and may be configured to be inclined as a whole.

In the illustrated embodiment, the coating tank 13,
More specifically, the fulcrum for tilting the movable plate 20 is selected so as to be located on one side of the electronic component main body 2, but may be selected so as to be located on the tip side of the lead wire 3. . Further, in the illustrated embodiment, the electronic component 1 with the lead wire is held while the lead wire 3 is in a horizontal or almost horizontal posture.
The coating tank 13, more specifically the movable plate 20, was tilted in order to remove the lead wire 3 from the bath of the resin 7, but on the contrary or in addition to this, the electronic device with the lead wire was tilted. The component 1 may be tilted. When the electronic component with lead wire 1 is tilted, the lead wire 3 only needs to be in a horizontal or almost horizontal posture at least when it is taken out of the bath of the resin 7, and is buried in the resin 7 in the coating tank 13. Sometimes it is not always necessary to be in a horizontal or nearly horizontal position.

Further, in the illustrated embodiment, the electronic component 1 with leads having two leads 3 is handled. However, the same applies to the electronic component with leads having three or more leads. Handling is possible. In the illustrated embodiment, the electronic component 1 with a lead wire to be handled is a radial lead type. However, the present invention can be applied to an electronic component with a lead line of an axial lead type. That is, when an insulating coating is formed on the lead wire of an electronic component with an axial lead type lead wire, a resin for insulating coating is applied to the lead wire on each side of the electronic component body at another stage. In this case, the above-described embodiment can be applied substantially as it is. Also, if two coating tanks are prepared and operated simultaneously, lead wires on each side can be used. At the same time, a resin can be applied.

[0032]

As described above, according to the present invention, the coating tank for storing the uncured resin is used, and the lead wire is provided so that a predetermined length of the lead wire is embedded in the uncured resin. Since the electronic component is positioned with respect to the coating tank, a resin serving as an insulating coating can be applied only to a necessary portion of the lead wire.

Therefore, the resin used as the insulating coating is
Since it is not provided so as to cover the entire insulating sheath on the electronic component body, the thickness of the electronic component body does not needlessly increase, and the mounting space of the electronic component with the insulating coating lead wire does not increase. . In addition, unnecessary resin is not consumed for insulating coating, and unnecessary cost can be suppressed.

Further, since the electronic component with the lead wire is positioned with respect to the coating tank, the length of the lead wire to which the resin is to be applied is determined quite accurately by the amount or form of the resin stored in the coating tank. can do. Therefore, the accuracy of the length of the insulating coating applied to the lead wire can be made relatively high. Further, according to the present invention, the electronic component with the lead wire is attached to the coating tank such that one end of a portion of the electronic component with the lead wire where the insulating coating is to be formed is in contact with one side edge defining the opening of the coating tank. After positioning, at least one of the coating tank and the electronic component with a lead wire is inclined so as to separate the other side edge opposite to the side where the one side edge is located from the portion where the insulating coating is to be formed, Thereby, the lead wire is taken out from the uncured resin bath in a state of taking a horizontal or almost horizontal posture.

Therefore, the posture of the lead wire at the time of this extraction is first horizontal or almost horizontal. In addition, by tilting at least one of the coating tank and the electronic component with a lead wire, uncured resin existing around the lead wire can be moved along the longitudinal direction of the lead wire. Extra resin does not adhere to the wire, and such dripping of the extra resin can be prevented. From these, the thickness of the obtained insulating coating can be made uniform or almost uniform in the longitudinal direction of the lead wire.

In the present invention, a notch selected to have a size capable of holding the uncured resin based on the surface tension thereof is formed at the other side edge of the coating tank, and an electronic device with a lead wire is provided. By positioning the lead wire in this notch in the process of positioning the component with respect to the coating tank, not only can the lead wire be more reliably embedded in the resin, but also the surface of the uncured resin Since the surface held by the tension defines the end of the resin application area on the lead wire, the dimension of the application area can be further stabilized.

[Brief description of the drawings]

FIG. 1 is a diagram showing a manufacturing apparatus 11 for carrying out a method for manufacturing an electronic component with an insulation-coated lead wire according to an embodiment of the present invention.
It is sectional front view which shows schematically.

FIG. 2 is a perspective view showing a positional relationship between the coating tank 13 and the electronic component 1 with lead wires shown in FIG.

FIG. 3 is a perspective view showing a state in which an uncured resin 7 is stored in a coating tank 13 shown in FIG. 2 at a portion where a notch 26 is provided.

FIG. 4 is a cross-sectional view schematically showing a state in which a movable plate 20 in the coating tank 13 shown in FIG. 1 is tilted.

FIG. 5 is a coating tank 13 performed after the step shown in FIG.
For explaining a process for separating the electronic component 1 with the lead wire from the coating tank 13 and the electronic component 1 with the lead wire.
It is a perspective view which shows each one part of FIG.

FIG. 6 is a front view showing an electronic component with leads 1 which is interesting for the present invention.

FIG. 7 is a schematic front view sequentially showing steps for forming an insulating sheath 4 which is performed to manufacture the electronic component 1 with leads shown in FIG.

8 is an illustrative front view sequentially showing a conventional process for forming an insulating coating 6 on the lead wire 3 of the electronic component with lead wire 1 shown in FIG.

[Explanation of symbols]

1 Electronic components with lead wires 2 Electronic component body 3 Lead wire 4 insulation sheath 6 Insulation coating 7 Uncured resin 11 Manufacturing equipment 13 Painting tank 15 Holder 18 Positioning rail 19 Fixing plate 20 movable plate 21 axes 23 opening 24 One side edge 25 The other side edge 26 Notch

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁷ Identification code FI H01G 13/00 321 H01G 1/02 Q (72) Inventor Masahisa Yasuhisa 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Murata Co., Ltd. In the factory (72) Inventor Toru Watanabe 2-26-10 Tenjin, Nagaokakyo-shi, Kyoto Murata Manufacturing Co., Ltd. (56) References JP-A-61-163602 (JP, A) Jika-sho-56-167536 (JP) , U) (58) Field surveyed (Int. Cl. ⁷ , DB name) H01G 4/224 B05D 5/12 B05D 7/00 H01C 1/034 H01C 17/00 H01G 13/00 321

Claims (2)

(57) [Claims] 1. A step of preparing an electronic component with a lead, comprising: an electronic component main body; a lead wire extending from the electronic component main body; and an insulating sheath covering the electronic component main body. A method for manufacturing an electronic component with an insulating coating lead wire, comprising a step of forming an insulating coating so as to cover a length portion, wherein an uncured resin serving as the insulating coating is stored to form a bath of the resin. Further comprising a step of preparing a coating tank having an opening, wherein the step of forming the insulating coating comprises forming a predetermined length portion of the lead wire in the uncured resin, and forming the insulating coating. The electronic component with the lead wire is positioned with respect to the coating tank so that one end of a part to be contacted is on one side edge defining the opening of the coating tank, and then the insulating coating is formed. Know, so release the other side edge opposite to the side where the one side edge portion is located,
Tilting at least one of the coating tank and the electronic component with the lead wire, thereby removing the lead wire from the bath of the uncured resin in the coating tank in a horizontal or almost horizontal posture, A method for manufacturing an electronic component with an insulating-coated lead, comprising: a step of curing the resin applied on a lead to form the insulating coating. 2. A notch selected to have a size capable of holding the uncured resin based on its surface tension is formed at the other side edge of the coating tank, and 2. The method of claim 1, wherein in the step of positioning the component with respect to the coating tank, the lead wire is positioned within the notch. 3.