U.S. patent application number 14/687255 was filed with the patent office on 2015-08-06 for method for connecting leader line.
This patent application is currently assigned to SUMIDA CORPORATION. The applicant listed for this patent is SUMIDA CORPORATION. Invention is credited to Yoshiyuki HATAYAMA, Yasunori MORIMOTO.
Application Number | 20150222070 14/687255 |
Document ID | / |
Family ID | 47742137 |
Filed Date | 2015-08-06 |
United States Patent
Application |
20150222070 |
Kind Code |
A1 |
MORIMOTO; Yasunori ; et
al. |
August 6, 2015 |
METHOD FOR CONNECTING LEADER LINE
Abstract
Disclosed is a method for connecting a core wire of a wire rod
covered with an insulating coating and pulled out from a coil
component with a substrate by irradiating a laser beam, the method
comprising the steps of: (a) forming a bond part between the wire
rod and the substrate, the bond part being made of a material
having a high optical absorptance for laser beam; and (b)
irradiating a laser beam on an area to be connected under a state
that at least one of the wire rod and the substrate is being pulled
toward the other.
Inventors: |
MORIMOTO; Yasunori; (Tokyo,
JP) ; HATAYAMA; Yoshiyuki; (Tokyo, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
SUMIDA CORPORATION |
Tokyo |
|
JP |
|
|
Assignee: |
SUMIDA CORPORATION
Tokyo
JP
|
Family ID: |
47742137 |
Appl. No.: |
14/687255 |
Filed: |
April 15, 2015 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
13561814 |
Jul 30, 2012 |
9035214 |
|
|
14687255 |
|
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Current U.S.
Class: |
29/860 |
Current CPC
Class: |
B23K 2101/32 20180801;
B23K 2101/38 20180801; H01F 41/10 20130101; B23K 2101/42 20180801;
B23K 26/323 20151001; B23K 2103/08 20180801; B23K 2101/34 20180801;
B23K 2103/12 20180801; B23K 26/20 20130101; H01R 43/0221 20130101;
B23K 1/0056 20130101; H01F 27/2828 20130101; Y10T 29/49179
20150115 |
International
Class: |
H01R 43/02 20060101
H01R043/02 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 29, 2011 |
JP |
2011-186493 |
Claims
1. A method for connecting a core wire of a wire rod pulled out
from a coil component with a substrate by irradiating a laser beam,
the method comprising the steps of: (a) forming a bond part between
the wire rod and the substrate, the wire rod being placed on the
bond part which is formed on the substrate; and (b) irradiating a
laser beam on an area to be connected where the wire rod and the
substrate are to be connected to each other via the bond part,
under a state that at least one of the wire rod and the substrate
is being pulled toward the other, wherein the laser beam is
irradiated on the area to be connected so that the bond part melts,
and the core wire of the wire rod sinks into the bond part.
2. The method according to claim 1, wherein the bond part is formed
of a material having a high optical absorptance for laser beam.
3. The method according to claim 2, wherein the bond part is formed
of a material containing at least tin.
4. The method according to claim 1, wherein a periphery of the core
wire of the wire rod is covered by the bond part.
Description
[0001] This is a Continuation of application Ser. No. 13/561,814
filed Jul. 30, 2012, which claims priority to Japanese Patent
Application No. 2011-186493 filed Aug. 29, 2011. The disclosure of
the prior applications are hereby incorporated by reference herein
in their entireties.
TECHNICAL FIELD
[0002] The present invention relates to a method for connecting a
leader line, in particular, to a method for connecting a core wire
of a wire rod of wire material pulled out from a coil component to
a substrate such as a terminal by irradiating a laser beam.
BACKGROUND ART
[0003] In general, a method, which has been known as a method for
connecting a core wire of a wire rod to a substrate such as a
terminal, includes: winding a wire rod having an insulating coating
formed on the periphery of the core wire around a substrate such as
a terminal, followed by soaking the wire rod in a solder tub,
removing the insulating coating from the wire rod by melting the
insulating coating under the melting heat of the solder; and
adhesion-fixing copper or the like, which is the core wire of the
wire rod, to the substrate such as the terminal.
[0004] Miniaturization and operating environment of electronic
apparatus have become severe in recent years. The operating
environment of electronic components, such as a coil incorporated
therein, has also become extremely severe. Therefore, the high heat
resistance of the electronic component itself has been also
requested simultaneously with miniaturization of electronic
components. In order to respond to such demands, for example, there
is no way to avoid the use of a wire having an insulating coating
with high heat resistance on the periphery of its core wire and the
use of a thin wire as a wire rod for the miniaturization of
electronic components. However, when connecting a wire rod to a
substrate such as a terminal, mechanical removal of an insulating
coating tends to cause wire disconnection. On the other hand, in
the case of removal of the insulating coating of a wire rod by
melting with the melting heat of solder, there is a problem of
difficulty in placing a miniaturized substrate into a solder
tub.
[0005] In recent years, therefore, other methods have been
proposed, where an insulating coating on the periphery of a core
wire of a wire rod is delaminated therefrom by burning with laser
beam irradiation, and simultaneously the core wire of the wire rod
is connected to a substrate such as a terminal.
[0006] For instance, Japanese Laid-Open Patent Publication No.
3-155300 (JP 3-155300 A) discloses a method including: previously
applying solder to a lead wire installed in a coil bobbin to form a
solder layer; winding a wire rod around the lead wire, the wire rod
being pulled out from a coil component and covered with an
insulating coating; melting the solder layer portion by laser beam
irradiation thereon; and burning an insulating coating with the
melting heat of solder to remove the insulating coating, while
connecting the wire rod to the lead wire. This method allows
soldering operation to be flexible even if electronic components
are miniaturized, compared with other conventional methods where
soaking in a solder tub is employed for connection.
SUMMARY OF INVENTION
Technical Problem
[0007] However, the invention disclosed in JP 3-155300 A, a leader
line from a coil is only wound around a lead wire which is provided
with a solder layer by application of solder. Therefore, removal of
the insulating coating and adhesion between the lead wire and the
leader line from the coil are not always performed in a reliable
manner even if performed by laser beam irradiation, resulting in
problem in reliability.
[0008] Accordingly the present invention has been made in
consideration of the aforementioned problem, and it is an object of
the present invention to provide a method for connection of a
leader line, which is able to remove an insulating coating from a
wire rod pulled out from a coil component and ensure adhesive
fixation between the core wire of the wire rod and a substrate.
Solution to Problem
[0009] Embodiments of the present invention have been proposed to
attain the above object. One aspect of the present invention is a
method for connecting a core wire of a wire rod covered with an
insulating coating and pulled out from a coil component with a
substrate, the method comprising the steps of: (a) forming a bond
part between the wire rod and the substrate, the bond part being
made of a material having a high optical absorptance for laser
beam; and (b) irradiating a laser beam on an area to be connected
under a state that at least one of the wire rod and the substrate
is being pulled toward the other.
[0010] The bond part may be formed of a material containing at
least tin.
[0011] The insulating coating may be colored blue or green.
Advantageous Effects of Invention
[0012] According to one aspect of the present invention, a wire rod
is arranged on the substrate via the bond part formed of the
material having a high optical absorptance for laser beam. A laser
beam is then irradiated on an area to be connected between the bond
part and the wire rod while force is applied so that at least one
of the wire rod and the substrate is pulled toward the other. As a
result, the bond part arranged between the wire rod and the
substrate generates heat. The heat burns the insulating coating of
the wire rod adhesively arranged on the bond part, and
simultaneously melts the bond part. Subsequently, a core wire of
the wire rod sinks into the bond part, and the periphery of the
core wire is covered by the bond part. A series of these actions
makes possible to remove the insulating covering from the wire rod
and to adhesively fix the substrate on the core wire on the wire
rod together, simultaneously. Consequently, these procedures can be
easily performed with high accuracy.
BRIEF DESCRIPTION OF DRAWINGS
[0013] FIG. 1 is a cross-sectional diagram schematically
illustrating a leader connector for carrying out a method for
connecting a leader line according to one embodiment of the present
invention; and
[0014] FIG. 2 is an explanatory diagram sequentially illustrating
the steps of the method for connecting a leader line according to
the embodiment of the present invention.
DESCRIPTION OF EMBODIMENTS
[0015] Hereinafter, a mode for carrying out the invention
(hereinafter, referred to as an "embodiment") will be described in
detail with reference to the attached drawings.
[0016] FIG. 1 is a cross-sectional diagram schematically
illustrating an exemplary leader connector for carrying out a
method for connecting a leader line according to an embodiment of
the preset invention. As depicted in FIG. 1, a leader connector 10
includes a laser beam irradiator 11 for irradiation of a laser
beam. A printed circuit board 16 is placed under the laser beam
irradiator 11. On the printed circuit board 16, a wire rod 12,
which is pulled out from a coil component (not shown), and a
substrate (such as a terminal formed as a wiring pattern or the
like) 15, which is to be connected to the wire rod 12 via a bond
part 14, are arranged. Here, for example, the printed circuit 16
may be a glass epoxy board. The substrate 15 may be formed by, for
example, application of phosphor bronze or the like is applied to
the print circuit board 16; or plating, coating, or printing of a
conductive metal on any of other metals (e.g., materials such as
plated tin, copper, silver, cadmium, and composites thereof).
[0017] The core rod 12 includes a conductive core wire 12a made of
copper or the like. The periphery of the core wire 12a is covered
with an insulating coating 13 made of polyurethane, polyimide, or
the like.
[0018] The laser beam irradiator 11 is configured to irradiate a
laser beam on the bond part 14 and keep the irradiation in a state
that the wire rod 12 is pulled toward the bond part 13 (i.e.,
pulled toward the substrate 15) to place them under tension T.
[0019] FIG. 2 is a diagram sequentially illustrating the steps of
an exemplary connection method using the leader connector 10
depicted in FIG. 1. In the figure, the core wire 12a of the wire
rod 12 pulled out from the coil component (not shown) is
adhesion-fixed on the substrate 15 via the bond part 14. Hereafter,
the connection steps (a) to (d) will be described in this order
with reference to FIG. 2.
[0020] First, using a known coating technique or the like, the bond
part 14 formed of a material having a high optical absorptance for
laser beam is placed on the substrate 15 of the printed circuit
board 16 (step (a)).
[0021] Next, under force that is tension T for pulling the wire rod
12, which has been pulled out from the coil component, toward the
substrate 15, the wire rod 12 is placed on the bond part 14 on the
substrate 15 and a laser beam is then irradiated on an area to be
connected where the wire rod 12 and the substrate 15 are to be
connected to each other via the bond part 14 (step (b)). In the
figure, reference sign "t" denotes "reaction force" acting from the
bond part 14 to the wire rod 12.
[0022] Tension T is applied so that the wire rod 12 can be pulled
toward the substrate 15, while a laser beam is irradiated on the
area to be connected. As a result, the bond part 14 absorbs the
laser beam and generates heat. Subsequently, the heat burns out the
insulating coating 13 of the wire rod 12, which is in contact with
the bond part 14. Then, the core wire 12a is exposed and the bond
part 14 starts to melt (step (c)).
[0023] The bond part 14 can be further softened by successively
irradiating the laser beam on the bond part 14 while applying
tension T so as to pull the wire rod 12 toward the substrate 15.
Due the presence of reaction force t as well as tension T pulling
the wire rod 12 toward the substrate 15, the core wire 12a of the
wire rod 12, which faces the substrate 15, sinks into the bond part
14. Thus, the periphery of the core wire 12a is brought into a
state of being covered with the bond part 14. After that, the laser
beam irradiation is stopped to cool and solidify the bond part 14,
completing the adhesion-fixing between the core wire 12a of the
wire rod 12 and the substrate 15 (step (d)).
[0024] Therefore, by completing the above steps (a) to (d), the
removal of the insulating coating 13 from the wire rod 12 and the
adhesion-fixing between the core wire 12a and the substrate 15
while being kept in conductive state can be simultaneously
attained. Therefore, the removal of the insulating coating 13 from
the wire rod 12 and the adhesion fixing between the core wire 12a
and the substrate 15 can be performed in a complete manner.
[0025] In summary, according to the present embodiment, the wire
rod 12 is arranged on the substrate 15 via the bond part 14 formed
of the material having a high optical absorptance for laser beam. A
laser beam is then irradiated on the area to be connected while
force is applied so that at least one of the wire rod 12 and the
substrate 15 is pulled toward the other. Then, heat is generated
from the bond part 14 which is formed by application or the like.
The heat burns the insulating coating 13 arranged in close contact
with the bond part 14, causing the core wire 12a of the wire rod 12
to be exposed. Simultaneously, the bond part 14 melts and becomes
soft. Since the core wire 12a of the wire rod 12 is pulled toward
the substrate 15, the core wire 12a of the wire rod 12, which faces
the substrate 15, sinks into the bond part 14. Thus, the periphery
of the core wire 12a is brought into a state of being covered with
the bond part 14. A series of these actions makes possible to
remove the insulating coating 13 from the wire rod 12 and to
adhesively fix the core wire 12a and the substrate 15 together
while being kept in conductive state can be simultaneously
attained.
[0026] The bond part 14 may be formed of any material as long as it
is easy to absorb laser beams. Among the materials, for example, it
may be formed of only tin or a tin-containing material.
[0027] Tin is applicable to soldering while having a high optical
absorptance for laser beam. Therefore, removal of the insulating
coating 13 from the wire rod 12 and adhesive fixing between the
core wire 12a and the substrate 15 can be much more easily
performed with high accuracy.
[0028] The laser beam may be any of beams of solid state laser, gas
laser, and liquid laser, or more specifically, for example, any of
beams of carbon dioxide gas laser, semiconductor laser, excimer
laser, and YAG laser.
[0029] In this embodiment, with respect to an area on which a laser
beam is directly irradiated on the insulating coating 13, it is
preferable that the wire rod 12 to be used may have a blue- or
green-colored insulating coating 13 to facilitate removal of the
insulating coating 13. Alternatively, any of other colors, such as
natural color (daytime color) may be applicable.
[0030] The use of blue- or green-colored insulating coating 13
facilitates removal of the insulating coating 13 more easily by
allowing the insulating film 13 being separated during the laser
beam irradiation.
[0031] In the above description, the bond part 14 has been
described as one being formed by application or the like on the
substrate 15. Alternatively, however, it may be applied to the
periphery of the wire rod 12 or may be applied to both the
substrate 15 and the wire rod 12.
[0032] In the above description, tension T has been described as
one for pulling the wire rod 12 toward the substrate 15.
Conversely, tension T may be applied for pulling the substrate 15
toward the wire rod 12.
[0033] The scope of the present invention is not limited to the
above embodiment. It goes without saying that the present invention
can be implemented in various modified modes without departing from
the gist of the present invention.
* * * * *