JP6181934B2 - Terminal connection structure and manufacturing method thereof - Google Patents

Description

  The present invention relates to an aluminum wire connecting terminal and a method for manufacturing the same.

In recent years , there has been a growing demand for lightweight and inexpensive aluminum wires, aiming to achieve both energy efficiency and cost. Although this electric wire has the above characteristics, when connecting to electrical equipment, the wiring inside the electrical equipment is often copper, so a means to connect copper and aluminum is necessary. It is often connected with . The this terminal connection and a method according to the method, a laser according to the method and fusing by methods and ultrasonic waves by soldering, have been proposed various methods. Again for connecting the aluminum wire of multiple solderability is present therein, a method of bonding reliability and excellent high since the entire connection portion can be firmly connected.

However, in general, when connecting an aluminum wire to a copper alloy terminal, the copper alloy terminal has a low thermal conductivity, so even if the terminal is heated by soldering, the aluminum wire inside the terminal is at the required temperature. However, there is a problem that flux and molten solder are difficult to be introduced into the entire inside of the terminal. Results or can voids in the solder as the reliability of the soldered or can point not easy Ku Electrical junction there is a problem of low. Voids are undesirable because they cause discharge, galvanic corrosion, increased electrical resistance, and heat generation during energization. Furthermore, there is a high possibility that air and moisture are present inside the void, and this kind of intervention makes it difficult to conduct heat and lowers the joining reliability. On the other hand, if the terminal and the end of the electric wire are caulked and compressed with a large force in order to reduce the void and improve the heat conduction, the electric wire may be damaged, and it may cause a disconnection.

  In addition, there exist patent document 1 and patent document 2 in the technique regarding joining of an electric wire and a terminal, for example. Patent Document 1 discloses a technique of a connection terminal that ultrasonically joins an aluminum electric wire and a copper terminal using an ultrasonic horn chip, and Patent Document 2 discloses an aluminum battledore unit body. A technique of a terminal fitting provided with an integral pipe-like conductor connecting portion, inserting a stranded conductor into the conductor connecting portion, and having a dissimilar metal layer that is a different metal from aluminum on the bottom surface of the vane plate body is disclosed.

JP 2007-12329 A JP 09-204947 A

  In view of the above, the applicant of the present application considers the terminal joint structure of the wire end portion shown in FIG. This structure is provided by the present applicant in Japanese Patent Application No. 2010-200802.

  The terminal junction structure of the electric wire end part of FIG. 11 is demonstrated. The terminal 11 includes a cylindrical terminal main portion 11a and a flat terminal piece 11b coupled to the terminal main portion 11a. The terminal piece 11b has a terminal hole 11c. The electric wire 12 is obtained by twisting together a large number of aluminum strands, and the enamel insulating coating is removed from the end 12a. The wire end portion 12a is inserted into the terminal main portion 11a and is exposed on the terminal piece 11b outside the terminal main portion 11a.

  A plurality of linear heat transfer members 13 are inserted into the wire end portion 12a with appropriate mutual intervals. The heat transfer member 13 forms a high heat path for introducing solder in the wire end portion 12a during soldering. In this state, during soldering, the first and second electrodes 14a and 14b are disposed radially outward of the terminal main portion 11a, and the third and fourth electrodes 15a and 15b are disposed radially outward of the terminal piece 11b. These are arranged opposite to each other.

  Next, as shown in FIG. 11 to FIG. 12, the first and second electrodes 14a and 14b are moved from the above arrangement positions in the directions indicated by the arrows and pressed against the terminal main portion 11a from both sides thereof, thereby the terminal main portion 11a. Is sandwiched between the first and second electrodes 14a and 14b. Similarly, as shown in FIGS. 10 to 11, the third and fourth electrodes 15a and 15b are moved from the arrangement position in the direction indicated by the arrow and pressed against the terminal piece 11b and the wire end 12a from both sides, Thus, the terminal piece 11b and the wire end portion 12a are sandwiched between the third and fourth electrodes 15a and 15b.

  In this state, a current is passed between the first and second electrodes 14a and 14b and between the third and fourth electrodes 15a and 15b to heat the terminal main portion 11a, the terminal piece 11b, and the wire end portion 12a. The heating of the wire end portion 12a by the third and fourth electrodes 15a and 15b is transferred to the wire end portion 12a via the heat transfer member 13 in the terminal main portion 11a, and as a result, the wire end portion in the terminal main portion 11a. 12a is heated evenly, flux and solder are efficiently introduced into the wire end portion 12a in the terminal main portion 11a, and reliable soldering is possible.

  However, when the wire end portion 12a exposed on the terminal piece 11b is divided into an end portion 12a1 in the vicinity of the terminal main portion 11a and an end portion 12a2 far from the terminal main portion 11a, the end portion 12a1 has the third electrode. The end 12a2 is not pressed inside the terminal piece 11b by 15a, and the end 12a2 is pressed inside the terminal piece 11b by the third electrode 15a.

  As a result, a sharp difference in height occurs between the end 12a1 and the end 12a2, and the wire end 12a is an aluminum element wire, so it is difficult to heat, and therefore, between the third and fourth electrodes 15a and 15b. The current that flows through is excessive. Moreover, it turned out that the heating temperature of end part 12a2 also becomes excessive by this, stress acts between end part 12a1, 12a2, and there exists a malfunction that the possibility that the electric wire end part 12a will be damaged becomes high.

  Therefore, the main object of the present invention is to provide a method for manufacturing such a terminal connection structure by improving the terminal connection structure without the sharp step and the shape of the third electrode.

  In order to achieve the above-mentioned object, the terminal connection structure according to the present invention is a terminal connection structure in which the end portion of the electric wire is exposed and soldered on the flat plate-shaped terminal piece coupled to the tip end side from the inside of the terminal main portion. When the electric wire end exposed from the terminal main part onto the terminal piece is divided into a first end side near the terminal main part and a second end side far from the terminal main part, The shape of the electric wire end portion in a side view is a shape compressed at the first end portion into a gently curved shape close to the terminal piece side toward the second end portion side.

  In the terminal connection structure of the present invention, the side view shape of the end of the electric wire exposed on the terminal piece is compressed into a gently curved surface close to the terminal piece side toward the second end side at the first end. Therefore, even if stress is applied between the first and second end portions, the stress is dispersed, and the end portion of the electric wire is cut off at the location exposed on the terminal piece from the terminal main portion. Therefore, a mechanically reliable terminal connection structure can be provided.

  In one aspect of the present invention, on the upper side which is the side farther from the soldering surface to which the wire end portion on the terminal piece is soldered, the inclination angle θ of the first intermediate portion in the longitudinal direction is 20 to 70 °. It is.

  In another aspect of the present invention, the soldering surface to which the end portion of the electric wire on the terminal piece is soldered has a concave portion having a gently inclined side wall surface. The recess is preferably provided with a protrusion that promotes heat conduction between the wire end and the terminal piece, or a protrusion around which the wire end is wound.

  As another aspect of the present invention, a pair of regulating walls for regulating the spread of the end portion of the electric wire on the soldering surface is provided on each side edge of the soldering surface to be soldered of the terminal piece.

  The method for manufacturing a terminal connection structure according to the present invention is a method for manufacturing a terminal connection structure in which an end portion of an electric wire is exposed and soldered onto a flat terminal piece continuous from the inner side of the terminal main portion to the tip end side thereof. And heating the terminal piece and the wire end by passing a current between the terminal piece and a wire end exposed on the terminal piece while pressing a pair of electrodes from both sides in the radial direction. And a step of introducing a flux onto the inner side of the terminal main part and the terminal piece in the heated state, and then introducing solder, and the radial direction of the electrode pressing the end of the wire of the two electrodes The terminal main portion side edge of the inner end is formed into a curved surface shape or a tapered surface shape.

  In the manufacturing method of the terminal connection structure of the present invention, since the terminal main part side edge of the inner end in the radial direction of the electrode pressing the wire end of both electrodes is formed into a curved surface shape or a tapered surface shape, When the pair of electrodes is pressed from both sides in the radial direction against the end of the electric wire exposed on the terminal piece, the end of the electric wire exposed on the terminal piece has a shape in a side view of the first end. It is pressed in a shape compressed into a gently curved surface so as to approach the terminal piece side toward the side. As a result, even if a stress acts between the first and second end portions, the stress is dispersed, and the end portion of the electric wire is not cut off at a portion exposed from the terminal main portion onto the terminal piece.

  In addition, when the terminal piece and the wire end are heated by passing an electric current between both electrodes, the current is totally dispersed from the first end side to the second end side of the wire end. As a result, the temperature rise due to heating of the end portion of the electric wire is moderated, and the solderability by subsequent introduction of flux and solder is improved. Further, in a state where the end of the electric wire is sandwiched between a pair of third and fourth electrodes opposed in the radial direction, an electric current is passed between the third and fourth electrodes to heat the end of the electric wire and solder the inner side of the terminal main portion. And flux are introduced and soldered. As a result, the end of the wire and the terminal are soldered without generating voids inside the terminal. A terminal connection structure in a state can be obtained.

  One aspect of the present invention is a method in which a current is passed between the first and second electrodes while a pair of first and second electrodes are pressed against the terminal main portion from both sides in the radial direction. Heating a wire end inside the main portion.

  Another aspect of the present invention includes the step of inserting a plurality of heat transfer members made of metal having a linear shape at the end of the electric wire and having a higher thermal conductivity than the end of the electric wire.

  In another aspect of the present invention, the surface of the terminal piece to which the end portion of the wire is soldered is provided with a concave portion having a gently inclined side wall surface, and the terminal piece of the two electrodes is provided. The pressing electrode presses the terminal piece portion at a position where the concave portion is removed on the side opposite to the terminal main portion.

  In still another aspect of the present invention, a pair of restricting walls are provided on both side edges of the terminal piece, and the step is executed by restricting the spread of the end portion of the electric wire exposed to the terminal piece by the pair of restricting walls.

  According to the terminal connection structure of the present invention, the end portion of the electric wire on the terminal piece is applied from the first end portion in the vicinity of the terminal main portion to the second end portion far from the terminal main portion, and the step shape having a gentle side view shape is obtained. Thus, since the wire ends are soldered in a state compressed in the radial direction, it is possible to provide a terminal connection structure in which the end portions of the electric wires are soldered with little thermal damage and less mechanical damage.

  In addition, according to the manufacturing method of the present invention, when the terminal piece and the wire end are heated by passing a current between both electrodes, the current flows from the first end side of the wire end to the second end. As a result, the flow is distributed as a whole toward the part side, the temperature rise due to heating of the end of the electric wire becomes moderate, and the solderability by the subsequent introduction of flux and solder is improved. In addition, in the state where the end of the electric wire on the terminal piece is sandwiched between a pair of third and fourth electrodes opposed in the radial direction, an electric current is passed between the third and fourth electrodes to heat the end of the electric wire, Since solder and flux are introduced and soldered on the inside, the end of the wire and the terminal are soldered without generating voids inside the terminal. As a result, defects caused by the void are eliminated and good It is possible to obtain a terminal connection structure in a proper solder connection state.

FIG. 1 is a perspective view of a terminal used in a terminal connection structure for an end portion of an electric wire according to an embodiment of the present invention. 2 is a cross-sectional view taken along line AA in FIG. 3A is an enlarged cross-sectional view of the main part of FIG. 2, FIG. 3B is a plan view, and FIG. 3C is a cross-sectional view along the line BB of FIG. FIG. 4 is a cross-sectional view of a state where the electric wire is inserted into the terminal main portion. FIG. 5A is a plan view showing a state in which the end of the electric wire is regulated by the restriction wall of the terminal piece, and FIG. 5B is a plan view showing an expanded state of the end of the electric wire when the terminal piece has no restriction wall. FIG. FIG. 6 is a cross-sectional view showing a state in which the end portion of the electric wire is inserted into the terminal main portion of the terminal and exposed on the terminal piece, and electrodes are arranged on both sides in the radial direction in each of the terminal main portion and the terminal piece. FIG. 7 is a diagram showing an example of each shape of the third electrode in FIG. FIG. 8 is a cross-sectional view showing a state in which the terminal main portion, the terminal piece, and the like are pressed by the first to fourth electrodes. FIG. 9 is a cross-sectional view of the terminal connection structure according to the embodiment after the first to fourth electrodes are removed in FIG. FIG. 10A is a plan view showing another embodiment, FIG. 10B is a longitudinal sectional view thereof, and FIG. 10C is a plan view showing a modification. FIG. 11 is a cross-sectional view illustrating a problem to be solved by the present invention in a state where the first to fourth electrodes are not pressed against the terminal main portion, the terminal pieces, and the like. 12 is a cross-sectional view of the first to fourth electrodes pressed from the state shown in FIG.

  The manufacturing method of the terminal connection structure of the electric wire end part which concerns on one Embodiment of this invention, and this structure are demonstrated. With reference to FIG. 1 thru | or FIG. 3, the terminal 11 is demonstrated in the said terminal connection structure. The terminal 11 includes a cylindrical terminal main portion 11a and a flat terminal piece 11b coupled to the tip end side thereof, and is made of copper, brass, another copper alloy, or a copper-based composite material. The terminal piece 11b has a terminal hole 11c. The terminal 11 has a metal plating layer (not shown) such as tin or solder formed on at least the inner surface of the terminal main portion 11a. A concave portion 11e is formed on the soldering surface 11d, which is the upper surface of the terminal piece 11b, and a pair of regulating walls 11f are provided on both side edges of the soldering surface 11d.

  The side wall surface 11g of the recess 11e has a gentle inclined surface as shown in an enlarged view in FIG. The side wall surface 11g may be a more gentle inclined surface as necessary. The concave portion 11e acts as a flux pool and a solder pool when the wire end portion 12a is soldered on the soldering surface 11d of the terminal piece 11b, thereby improving the soldering. There may be one or more recesses 11e. The width of the recess 11e in the direction perpendicular to the longitudinal direction C is approximately the same as the entire width of the wire end 12a, and the length is shorter than the width. The depth of the recess 11e is about ½ of the thickness of the terminal piece 11b.

  A plurality of protrusions 110 are provided on the bottom surface of the recess 11e. Each protrusion 110 has an elongated shape extending in the longitudinal direction C, which is the axial direction, as can be seen from FIG. The protruding end surface of the protrusion 110 is positioned flush with or slightly above or below the soldering surface 11d, which is the upper surface of the terminal piece 11b. A part of the wire end portion 12a passes between the protrusions 110 and 110. The protrusion 110 increases the contact area between the wire end 12a and the terminal piece 11b, promotes heat conduction between the two ends 12a and 11b, and can uniformly heat the inside of the wire end 12a. Good soldering. In addition, since the tip surface of the protrusion 110 approaches the electrode 15a, heat transfer from the electrode 15a is improved, which is particularly effective when an aluminum electric wire having a lower thermal conductivity than copper is used. Note that the protrusion 110 may not be provided.

  Further, the restriction wall 11f rises in the direction of the soldering surface 11d so that the spread of the wire end 12a can be restricted as shown in FIGS. 5 (a) and 5 (b). In order to perform this regulation effectively, it is preferable to place the regulation wall 11f on the side of the recess 11e.

  In the terminal 11 having the above configuration, as shown in FIG. 4, an electric wire 12 made of aluminum, copper, or the like is attached from one side opening of the terminal main portion 11a, and the end portion 12a on the tip side is inside the terminal main portion 11a. And it solders on the soldering surface 11d which is the upper surface of the terminal piece 11b. The electric wire 12 is composed of a stranded wire in which a large number of aluminum strands are twisted together. The end portion of the stranded wire has the enamel insulation coating removed. In the following description, the stranded wire has been previously removed at places where the enamel insulation coating needs to be removed. However, the present invention is not limited to a stranded wire, and includes an assembly line in which a plurality of wires are simply assembled.

  A plurality of linear heat transfer members 13 are inserted in parallel to the longitudinal direction C of the wire end portion 12a with a predetermined distance from each other in the wire end portion 12a inside the terminal main portion 11a. The heat transfer member 13 is inserted in a wire shape so as to form a high heat path in the wire end 12a during soldering, and solder (not shown) is introduced into the inserted terminal main part 11a via the high heat path. Is done. The heat transfer member 13 also has a function of promoting the flow of solder and flux in the wire end portion 12a. A plurality of heat transfer members 13 may be inserted into the wire end portion 12a, or only one may be inserted.

  The heat transfer member 13 is made of, for example, copper, which is a metal having higher thermal conductivity than the wire end portion 12a, and a metal plating layer of, for example, tin or solder having a thickness of about 6 to 10 μm is formed on the surface of the material. A high heat path is more easily formed by melting a metal plating layer (not shown) on the surface of the terminal 11 due to the high heat applied to the terminal 11 during soldering and also melting the metal plating layer on the surface of the heat transfer body 13. It is like that.

  As shown in FIG. 5A, the wire end portion 12a is aligned along the regulating wall 11f without spreading by the pair of regulating walls 11f on the soldering surface 11d of the terminal piece 11b. Without the regulating wall 11f, as shown in FIG. 5B, the wire end portion 12a spreads on the soldering surface 11d, so that the soldering cannot be performed satisfactorily.

  Next, the soldering method of the embodiment will be described with reference to FIGS. First, as shown in FIG. 6, the wire end portion 12a is inserted through the terminal main portion 11a and exposed on the terminal piece 11b outside the terminal main portion 11a. Next, the pair of first and second electrodes 14a and 14b are disposed opposite to the terminal main portion 11a in the radial direction, and the terminal piece 11b is formed outside the terminal main portion 11a. A pair of third and fourth electrodes 15a and 15b are disposed opposite to the electric wire end 12a in the radially outward direction.

  In this case, each of the first, second electrodes 14a, 14b and the fourth electrode 15b has a cubic shape, whereas the third electrode 15a has a radius as shown in FIG. 7 (a1). The edge on the terminal main portion 11a side at the inner end in the direction has a predetermined curved surface shape that bulges toward the terminal main portion 11a. Explaining the shape of this curved surface, as shown in FIG. 7A2, for example, the third electrode 15a is orthogonal to the soldering surface 11d of the terminal piece 11b from the terminal main portion 11a, that is, orthogonal to the longitudinal direction C. Between the flat side surface S1 extending in the direction and the flat bottom surface S2 facing the wire end 12a on the terminal piece 11b, there is a curved surface S3 that gently curves with a large curvature radius.

  The shape of the curved surface S3 includes a shape that changes exponentially or parabolically in addition to the partial cylindrical surface. In this case, as shown in FIG. 7B, the third electrode 15a may have the curved surface S4 with the curved surface formed without the side surface S1 and the entire surface facing the wire end portion 12a. Alternatively, instead of the curved surface, a flat tapered surface S5 may be used as shown in FIG. Even in the case of the flat tapered surface S5, the electric wire portion pressed against the tapered surface S5 becomes a curved surface by the spring back.

  Next, as shown in FIG. 8, the terminal main portion 11a is held between the first and second electrodes 14a and 14b by pressing the first and second electrodes 14a and 14b from both sides in the radial direction against the terminal main portion 11a. In this state, a current is passed between the first and second electrodes 14a and 14b to heat the terminal main portion 11a.

  Similarly, by pressing the third and fourth electrodes 15a and 15b from both sides in the radial direction against the terminal piece 11b and the electric wire end 12a on the outside of the terminal main part 11a, the electric wire end 12a together with the terminal piece 11b 3. In this state, a current is passed between the third and fourth electrodes 15a and 15b to heat the terminal piece 11b and the wire end portion 12a. The method of applying this current is not particularly limited.

  In this case, since the edge 15a1 on the terminal main portion 11a side at the radially inner end of the third electrode 15a is the curved surface S3 or the tapered surface S5, the wire end portion 12a is connected to the vicinity of the terminal main portion 11a. When the first end portion 12a1 and the second end portion 12a2 on the distal end side far from the terminal main portion 11a are divided, the first end portion 12a1 is directed toward the second end portion 12a2, that is, toward the distal end side. The shape is a gentle curve or taper so as to be close to the terminal piece 11b. Therefore, when the third and fourth electrodes 15a and 15b are pressed against the wire end 12a on the terminal piece 11b and soldered, the first end 12a1 of the wire end 12a is connected to the third electrode 15a. Thus, the second end 12a2 is not pressed against the soldering surface 11d by the third electrode 15a without being pressed against the soldering surface 11d inside the terminal piece 11b. As a result, there is no need for a steep step between the first end 12a1 and the second end 12a2.

  That is, the rear end edge 121 that is the uppermost portion on the upper side (the side far from the terminal piece 11) of the curved first end portion 12a1 of the electric wire end portion 12a and the portion where the straight line portion starts after the bending ends. The ratio between the rear end edge 122 of the two end portions 12a2 is gently inclined, and the ratio L / H between the longitudinal dimension L between the rear end edges 121 and 122 and the height difference H thereof is 0. It is 4-2.8, Preferably it is 0.7-2.5, More preferably, it is 1.0-2.0. When the three ranges of the ratio L / H are represented by an inclination angle θ with respect to the longitudinal direction C of the longitudinal middle portion 12m of the first end portion 12a1, it is 20 to 70 °, preferably 20 to 55 °, and more preferably 25. ~ 45 °. When the inclination angle θ is 70 ° or more, the first end portion 12a1 becomes a sharp curved surface, and the wire end portion 12a is easily damaged. When the inclination angle θ is less than 20 °, the first end portion 12a1 is It becomes too long, leading to an increase in the size of the terminal connection structure.

Further, between the third and fourth electrodes 15a and 15b, the portion of the terminal piece 11b having no recess 11e is pressed from both sides with the wire end 12a sandwiched therebetween, so the second end 12a2 of the wire end 12a. While a sufficient amount of current flows through the side to be heated, the temperature in the recess 11e does not need to be raised and the heat is gradually transferred. The heat accumulated in the recess 11e gradually evaporates by this heat, and the solder introduced from the second end 12a2 to the first end 12a1 is sufficiently introduced into the end of the electric wire and soldered. In this case, since there is a recess 11e and the side wall surface 11g of the recess 11e is gentle, and the edge 15a1 of the third electrode 15a is tapered, the wire end 12a is not damaged by heat. The mechanical damage is also small because there is little and no excessive stress is applied.

  From the above, the wire end portion 12a outside the terminal main portion 11a does not cause a sharp difference in height between the first end portion 12a1 and the second end portion 12a2. As a result, the wire end portion 12a can be soldered and connected to the soldering surface 11d of the terminal piece 11b with high reliability.

  The heat transfer member 13 is substantially parallel to the stranded wire of the wire end 12a in the wire end 12a. When the terminal main portion 11a is heated from the outside, high heat is transmitted to the heat transfer member 13, whereby the metal plating layer on the surface of the heat transfer portion 13 is melted, and a high heat path is formed around the heat transfer portion 13. In this state, flux and molten solder such as aluminum solder are introduced into the terminal main portion 11a from above. The flux introduced inside the terminal main portion 11a flows into the electric wire end portion 12a along the heat transfer portion 13 that has become high temperature, and spreads inside the terminal main portion 11a.

  Further, the flux is sucked into the wire end portion 12a by the capillary phenomenon due to the gap around the heat transfer portion 13. Thereby, the flux acts on the surface of the wire end portion 12a, and the oxide film formed on the surface of the wire end portion 12a is removed. Next, the introduced molten solder is guided to the heat transfer portion 13 and flows into the electric wire end portion 12a, like the flux. Thereby, solder spreads inside the terminal main part 11a, and connects the stranded wires in the electric wire end part 12a and the electric wire end part 12a and the terminal main part 11a. Thus, the flux acts on the surface of the wire end portion 12a inside the terminal main portion 11a, and the molten solder comes into contact with the wire end portion 12a from which the oxide film has been removed by the flux. No good soldering part is formed.

  FIG. 9 shows a terminal joint structure at the end of the wire after soldering without an electrode. FIG. 9 shows a terminal connection structure after the electrodes are removed after soldering in FIG.

  10A to 10C show another embodiment. As shown in FIGS. 10A and 10B, a protrusion 112 is provided at the center of the recess 11 e, and the second end 12 a 2 of the wire end 12 a is wound around the protrusion 112. A recess 130 is formed in the bottom surface of the upper third electrode 15a so that the tip of the protrusion 112 enters, and the second end 12a2 is pushed into the recess 11e by the third electrode 15a, and the solder collected in the recess 11e. Is firmly joined to the terminal 11. A plurality of protrusions 112 may be provided.

  Further, as shown in FIG. 10C, the wire end portion 12 a may be divided into two in the width direction orthogonal to the longitudinal direction C and wound around the protrusion 112. Thereby, the inside of the electric wire end part 12a is heated uniformly.

11 terminal 11a terminal main part 11b terminal piece 11d soldering surface 11e recess 11g side wall surface 11f regulating wall 12 electric wire 12a electric wire end 13 heat transfer member 14a first electrode 14b second electrode 15a third electrode (electrode for pressing electric wire end) )
15b 4th electrode (electrode to press the end of the wire)
110 Projection for heat conduction 112 Projection for winding S3, S4 Curved surface S5 Tapered surface θ Inclination angle

Claims (8)

A terminal connection structure in which the end of the electric wire is exposed and soldered onto a flat terminal piece connected to the tip side of the terminal main portion from the inside,
When the electric wire end exposed on the terminal piece from the terminal main part is divided into the first end part near the terminal main part and the second end part far from the terminal main part,
The shape of the electric wire end portion in a side view is a shape that is compressed into a gently curved surface that is close to the terminal piece side toward the second end portion side in the first end portion,
Further, the soldering surface to which the end of the electric wire on the terminal piece is soldered has a concave portion whose side wall surface is a gently inclined surface ,
The recess is provided with a protrusion that promotes heat conduction between the wire end and the terminal piece,
Terminal junction structure at the end of the wire. The structure according to claim 1 , wherein a protrusion around which the end of the electric wire is wound is provided in the recess. In the upper to be farther from the soldering surface of the electric wire end portion on the strip the terminal is soldered, the inclination angle of the longitudinal direction intermediate portion of the first end portion θ is 20 to 70 °, according to claim 1 or 2. The structure according to 2 . Each side edge of the soldering surface to be soldered of the terminal strip, having a pair of regulation walls for restricting the spread of the electric wire end portion on the soldering surface, in any one of claims 1 to 3 Description structure. A method of manufacturing a terminal connection structure in which an end portion of an electric wire is exposed and soldered on a flat plate-shaped terminal piece coupled to the tip end side of the terminal main portion from the inside,
Heating the terminal piece and the wire end by passing a current between the terminal piece and a wire end exposed on the terminal piece while pressing a pair of electrodes from both sides in the radial direction; ,
Introducing flux and solder on the inside of the terminal main part and on the terminal piece in the heated state,
The terminal main portion side edge of the inner end in the radial direction of the electrode that presses the wire end portion of the two electrodes is formed into a curved surface shape or a tapered surface shape,
A concave surface having a gentle slope is provided on a soldering surface of the terminal piece to which the end of the electric wire is soldered, and an electrode that presses the terminal piece out of the two electrodes has the concave portion as the main terminal. In the state where the terminal piece portion at the position removed on the side opposite to the portion is pressed, the step is executed.
Manufacturing method of terminal connection structure. A step of heating the terminal main portion and the wire end inside the terminal main portion by passing a current between the other pair of electrodes while pressing another pair of electrodes against both sides of the terminal main portion in the radial direction. The manufacturing method of Claim 5 containing this. The method according to claim 5 or 6 , comprising a step of inserting a plurality of heat transfer members made of metal having a linear shape at the end of the electric wire and having a higher thermal conductivity than the end of the electric wire. A pair of regulation walls on the terminal strip side edges, to regulate the extent of the electric wire end portion exposed to the terminal piece by the pair of regulation walls, executing the step, any one of claims 5 to 7 The method according to item.

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