JP2008305571A - Crimp terminal and method for manufacturing crimp terminal - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a crimp terminal having a new structure in which electrical resistance in a region connected to an electric wire can be efficiently reduced with a simple structure and shape without being enlarged. <P>SOLUTION: In the crimp terminal 10 crimped to the outer peripheral surface of the electric wire 12, on the inner surface of the crimping part 16, a plurality of strips of recesses and projections 26 for conduction are provided which extend in the same direction as that of the electric wire 12 over an area longer than a semicircle of the outer peripheral surface of the electric wire 12 in the circumferential direction. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a conductive crimp terminal attached by crimping to an electric wire, an electric wire provided with such a crimp terminal, and a method of manufacturing such a crimp terminal.

  Conventionally, various terminals have been used for electrical connection portions with respect to other members of an electric wire for the purpose of stabilizing conduction and facilitating attachment / detachment work at the connection portions. As one type of terminal, there is known a crimp terminal that is formed by integrally forming a crimp portion on the terminal, and crimping and fixing the crimp portion to the outer peripheral surface of the electric wire and directly crimping the wire.

  By the way, in the connection part to the other member of an electric wire, in order to suppress electric power loss, it is requested | required that electrical resistance should be made small enough. In order to suppress the electric resistance, for example, it is conceivable to increase the diameter of the electric wire or enlarge the crimp terminal.

  However, the increase in the diameter of the electric wire and the increase in the size of the crimp terminal are limited by the installation space, are troublesome to handle, and increase the cost significantly, and thus are not easily adopted.

  Moreover, although it is possible to suppress the electrical resistance of the electric wire and the crimp terminal itself by enlarging the diameter of the electric wire or increasing the size of the crimp terminal, the contact resistance of the connection portion between the electric wire and the crimp terminal should be sufficiently suppressed. Is difficult. Therefore, there is a problem that the electrical resistance of such a connection part becomes a bottleneck, and it is difficult to sufficiently reduce the electrical resistance.

In particular, in order to prevent the wire from coming out of the crimp terminal, as described in Japanese Utility Model Laid-Open No. 05-23389 (Patent Document 1), the circumference of the wire is It has been proposed to form a circumferential ridge extending in the direction and lock the circumferential ridge so as to bite into the electric wire, but when such a circumferential ridge is formed, In the longitudinal direction, a gap is easily generated between the inner surface of the crimp terminal at both sides sandwiching the circumferential protrusion. And since the contact area of an electric wire and a crimp terminal becomes small by this clearance gap, there also existed a possibility that the electrical resistance in the connection part of an electric wire and a crimp terminal might become still larger.

Japanese Utility Model Publication No. 05-23389

  Here, the present invention has been made against the background as described above, and the problem to be solved is that it is possible to reduce the electrical resistance at the connection site with respect to the electric wire, and thereby the electric wire and the crimp terminal. An object of the present invention is to provide a crimp terminal having a novel structure capable of effectively suppressing power loss during energization while avoiding an increase in size.

Another object of the present invention is to provide an electric wire with a crimp terminal provided with such a crimp terminal and a suitable method for producing such a crimp terminal.

  Hereinafter, the aspect of this invention made in order to solve the above-mentioned subject is described. In addition, the component employ | adopted in each aspect as described below is employable by arbitrary combinations as much as possible. Further, aspects or technical features of the present invention are not limited to those described below, but are described in the entire specification and drawings, or an invention that can be understood by those skilled in the art from those descriptions. It should be understood that it is recognized based on thought.

  That is, a feature of the present invention is a crimp terminal that is crimped to the outer peripheral surface of the electric wire, and the inner surface of the crimp portion that is crimped to the outer peripheral surface of the electric wire is a region that extends over a half circumference in the circumferential direction of the electric wire. In the crimp terminal, a plurality of conductive irregularities extending in the same direction as the electric wire are formed.

  In the crimp terminal having such a structure according to the present invention, the contact area between the crimp part and the electric wire is increased by increasing the area of the inner surface of the crimp part by the concavity and convexity for conduction.

  In addition, since the conductive irregularities extend in the same direction as the electric wires, the bottom surfaces of the concave portions and the tip surfaces of the convex portions of the conductive irregularities can be effectively brought into contact with each other in a shape along the outer peripheral surface of the electric wires. Thereby, the trouble that a big clearance gap arises between the crimping | compression-bonding part provided with the unevenness | corrugation for conduction | electrical_connection and the contact surface of an electric wire is avoided, and a contact area is fully ensured.

  Therefore, according to the crimp terminal of the present invention, since the contact area with the electric wire is effectively increased, the attachment portion of the crimp terminal to the electric wire can be achieved without enlarging the diameter of the electric wire or increasing the size of the crimp terminal. In addition to reducing the electrical resistance in the power supply and suppressing the power loss during energization, the frictional force proportional to the contact area and the contact pressure is increased. This also improves the adhesion strength.

  Further, in the crimp terminal according to the present invention, the inner surface of the crimp portion is formed with a locking unevenness extending in a circumferential direction of the electric wire in a region different from the region where the conductive unevenness is formed. A structure in which the concave and convex portions for locking come into contact with the outer peripheral surface of each of them may be adopted. According to such a structure, the engagement unevenness is crimped to the electric wire so as to partially bite the electric wire in the longitudinal direction that is the electric wire removal direction, thereby preventing the crimp terminal from coming out of the electric wire. A stopping effect can be exerted. In particular, in this aspect, the increase in the contact area of the crimp terminal to the electric wire due to the conductive unevenness is not hindered by the locking unevenness.

  However, it is also possible to employ, for example, irregularities in an aspect extending in the circumferential direction of the electric wire as the irregularities for locking, and in addition to the irregularities in the aspect extending in the circumferential direction of the electric wire as the irregularities for locking. You may form the unevenness | corrugation extended in the length direction of an electric wire piled up. In the formation area of the concavity and convexity for conduction, the contact area of the electric wire with respect to the crimp terminal is sufficiently ensured, and in the formation area of the concavity and convexity for locking, the securing of the contact area to the electric wire is not considered so important. The emphasis can be placed on the locking action to the surface, so that various types of locking irregularities can be adopted, and even when such various types of locking irregularities are employed, as described above Further, the effects of the present invention such as reduction of energization resistance and increase of wire pulling effect due to the conductive irregularities can be exhibited.

  Note that, in the crimp terminal according to the present invention, the structure in which the engaging unevenness and the conductive unevenness extending in the circumferential direction of the electric wire are alternately formed in the length direction of the electric wire at the contact portion with the outer peripheral surface of the electric wire. However, it may be adopted.

  Further, in the crimp terminal according to the present invention, the outer peripheral surface of the electric wire is covered with an insulation coating, and the crimp portion is crimped to the exposed portion of the electric wire partially exposed from the insulation coating in the length direction of the electric wire. In addition, a fixing portion for insulating coating that is crimped to the outer peripheral surface of the insulating coating covering the electric wire is provided, and the inner peripheral surface of the insulating coating fixing portion is provided in the circumferential direction of the electric wire. A structure in which fixing irregularities extending in the direction are formed may be employed. According to such a structure, the crimp terminal is directly fixed to the insulation coating, and the displacement of the insulation coating with respect to the electric wire, such as turning up of the insulation coating, is prevented.

  Further, in the crimp terminal according to the present invention, the crimp portion is configured to include a bottom wall portion and a pair of caulking portions rising from both sides in the width direction of the bottom wall portion, and at least the bottom wall portion of the crimp portion is electrically connected. A structure in which irregularities are formed may be employed. According to such a structure, the crimping operation is easily and surely realized by using the caulking fixing of the caulking portion, and the conductive irregularities are formed at least on the bottom wall portion of the crimping portion. The abutting area can be suitably secured.

  Furthermore, a feature of the present invention is an electric wire with a crimp terminal to which the above-mentioned crimp terminal is fixed, wherein the crimp portion of the crimp terminal is crimped to the electric wire, and the conductive irregularities are formed on the outer peripheral surface of the electric wire. On the other hand, it is in the electric wire with a crimping terminal that is in contact with over a half circumference.

  Moreover, in the electric wire with a crimp terminal according to the present invention, the electric wire is a multi-core electric wire in which a plurality of fine wires are bundled in parallel, and the concave and convex portions for conduction are larger in radius of curvature than the fine wires of the multi-core electric wire. A structure having an arcuate curved concave shape having the shape may be adopted. According to such a structure, a plurality of fine wires can be brought into contact with each other so as to enter the concave portion of the conductive irregularity, thereby further efficiently ensuring the contact area of the conductive irregularity with the electric wire. It becomes possible.

  Furthermore, the feature of the present invention relating to the method of manufacturing the crimp terminal is that when the crimp terminal having the structure according to the present invention as described above is manufactured by punching the blank, Then, after forming conductive concavities and convexities on the surface of the base plate by press working, the crimping portion is formed by punching the base plate.

  According to such a method of the present invention, since the conductive irregularities are formed prior to the crimping part, for example, the base plate is punched to form the crimping part, and then press working is performed to form the conductive irregularities. In some cases, it is possible to avoid the possibility that the end portion of the conductive unevenness is generated as a burr at the end edge portion of the pressure-bonding portion along with the plastic deformation during press molding of the conductive unevenness.

  Further, in the method for manufacturing a crimp terminal according to the present invention, a progressive plate having a long plate shape is adopted as a blank, and the progressive plate is fed to a plurality of stages to perform a multi-stage press process. In addition, a method of performing a punching process on a portion where the conductive unevenness is formed on another stage after the press working stage for forming the conductive unevenness may be employed. Thereby, manufacturing efficiency is improved and mass production of crimp terminals can be advantageously realized.

  Hereinafter, in order to clarify the present invention more specifically, embodiments of the present invention will be described. 1 and 2 show a terminal fitting 10 as an embodiment according to the crimp terminal of the present invention. As shown in FIGS. 3 and 4, for example, the terminal fitting 10 is attached by crimping to an electric wire 12 that electrically connects parts of an electric machine or an electronic device of an automobile. It has become. If the electric wire 12 with a crimp terminal by which such a terminal metal fitting 10 was crimped is illustrated concretely, it will be a clamping bolt with respect to the end part of the earthing electricity wire which earth-connects the negative terminal of the battery of a motor vehicle to a body. A terminal with a washer for insertion, or a power line connected to a power supply cord of various electronic devices, and a terminal such as a flat terminal or a terminal for fixing to the power supply cord is fixed. Things.

  More specifically, the terminal fitting 10 is formed using various metal materials that have conductivity and can be pressed or punched, such as brass, copper, copper alloy, aluminum, aluminum alloy, and the like. Has been. In the present embodiment, the thickness dimension of the terminal fitting 10 is substantially constant over the entire area, but portions with greatly different thickness dimensions are partially formed depending on required manufacturability, electrical resistance, and the like. May be. Although the shape of the terminal fitting 10 is not particularly limited, in the present embodiment, the terminal fitting 10 is integrally formed including the connection portion 14 and the crimping portion 16.

  The connecting portion 14 has a flat plate shape with a substantially elliptical plane, and a through hole 18 is provided through the central portion. For example, in the case of the above-described grounding wire, the through hole 18 is used to insert a tightening bolt that is screwed into the body ground portion.

  The crimping part 16 extends from one place on the circumference of the outer peripheral edge of the connection part 14 and is integrally formed. Further, the crimping portion 16 has a substantially groove shape that linearly extends from the connection portion 14 outward (downward in FIG. 1). That is, the crimping portion 16 includes a bottom wall portion 20 having a substantially rectangular plate shape that is long, and both side edges of the bottom wall portion 20 in the width direction (left and right directions in FIGS. 1 and 2) A pair of caulking portions 22 and 22 rising on one surface side (upper surface side in FIG. 2) is formed. These caulking portions 22, 22 are formed in a substantially rectangular plate shape over the entire length in the length direction of the bottom wall portion 20, and constitute both side walls of the bottom wall portion 20. The portion 16 has a groove shape with a substantially constant concave cross section.

  Reinforcing portions 23, 23 extending along the outer peripheral edge portion of the connecting portion 14 from the respective end faces in the length direction of the crimping portions 22, 22 of the crimping portion 16 are provided at the connecting portion of the connecting portion 14 and the crimping portion 16. Stands up and is integrally formed. Further, a bent portion 24 that is slightly bent inward is integrally formed at the tip edge portion of each caulking portion 22.

  Here, a plurality of concave grooves 26 are formed in the crimping portion 16 over substantially the entire inner surface thereof. The concave groove 26 is formed on a groove inner surface (hereinafter also referred to as an inner surface of the crimping portion 16) that is a surface on the side where the pair of caulking portions 22, 22 in the crimping portion 16 rises from the bottom wall portion 20. Is formed. As is clear from this, in this embodiment, the concave groove 26 is formed in at least the bottom wall portion 20 of the crimping portion 16. Further, the concave groove 26 has a substantially constant cross-sectional shape (substantially semicircular shape in the present embodiment), and is linearly continuous in the length direction of the pressure-bonding portion 16 having a groove shape, that is, in the vertical direction in FIG. Extended.

  Each concave groove 26 may be divided in the length direction or may be partially formed in the length direction of the crimping portion 16, but in the present embodiment, substantially in the length direction of the crimping portion 16. The groove 26 is formed continuously over the entire length, and each concave groove 26 is opened at the distal end surface of the crimping portion 16 in the length direction. In addition, although the depth dimension of the concave groove 26 is not particularly limited, in order to ensure the strength of the crimping portion 16, it is preferably 2/3 or less of the member thickness of the crimping portion 16, more preferably 1 /. 2 or less.

  A plurality of such concave grooves 26 are provided at a predetermined distance in the width direction of the crimping portion 16. In particular, in this embodiment, the bottom wall portion 20 and the two caulking portions 22 and 22 are formed with a total of eight strips at substantially equal intervals.

  As a result, the concave inner surfaces of the plurality of concave grooves 26 and the substantially flat surface at the distal end portion further than the outermost concave grooves 26 between the concave grooves 26, 26 adjacent to each other and the caulking portions 22, 22. Thus, the inner surface of the crimping portion 16 is formed, and the entire surface has a concavo-convex shape. That is, the plurality of concave grooves 26 and the flat portion constitute conductive irregularities over substantially the entire inner surface of the crimping portion 16.

  The terminal fitting 10 having the above-described structure is crimped to the electric wire 12 as shown in FIGS. The electric wire 12 is a multi-core electric wire in which a plurality of thin wires 28 made of copper, aluminum, or other metal wires used as a conductor for passing current are bundled in parallel. Further, the outer peripheral surface of the electric wire 12 that requires insulation is covered with an insulating coating 30 having electrical insulation such as ethylene resin or styrene resin.

  In particular, in the present embodiment, the thin wire 28 extends with a substantially constant circular cross section, and the concave groove 26 of the terminal fitting 10 has an arcuate curved concave shape having a radius of curvature larger than the radius of the thin wire 28. Particularly preferably, the inner diameter dimension (curvature radius) D2 of the concave groove 26 is D1 / D2 ≦ 1/2 with respect to the outer diameter dimension D1 of the thin wire 28. More preferably, D1 / D2 ≦ 1/3, and more preferably D1 / D2 ≦ 1/5.

  In order to crimp the terminal fitting 10 according to the present embodiment on the electric wire 12 composed of the plurality of thin wires 28, the longitudinal direction of the terminal fitting 10, that is, the extending direction of the plurality of conductive irregularities is substantially the same as the longitudinal direction of the electric wire 12. For example, a known caulking device as shown in Patent Document 1 (Japanese Utility Model Laid-Open No. 05-23389) is used in a state where the electric wire 12 is placed on the bottom wall portion 20 in the groove of the crimping portion 16 so as to extend in parallel. Then, the crimping portion 16 including the pair of caulking portions 22 and 22 is caulked. As a result, as shown in FIGS. 3 and 4, the crimping portion 16 including the pair of caulking portions 22 and 22 is plastically deformed, and the electric wire 12 is exposed so as to wrap the electric wire 12 from the outer peripheral surface. The crimping part 16 is crimped | bonded with respect to an edge part. Thereby, the inner surface of the crimping part 16 is brought into contact with the outermost peripheral surface of the electric wire 12 composed of multiple wires in a crimped state.

  Further, in the present embodiment, the bent portions 24 and 24 bent inward are formed at the tip portions of the caulking portions 22 and 22, respectively. Against the inner side, it is more strongly crimped. In addition, the end portions of the caulking portions 22, 22 are overlapped so as to partially embrace the multi-wire electric wires 12, so that a larger crimping force is exerted on the thin wire 28 and the crimping portion 16 of the thin wire 28. It is designed to prevent slipping out of the camera.

  By such crimping by caulking, the inner surface of each groove 26 in the crimping part 16 is curved into a shape along the outer peripheral surface of the electric wire 12 as a whole and is in contact with the surface of the thin wire 28. That is, a plurality of concave grooves 26 extending in the same direction as the electric wire 12 are formed in the inner surface of the crimping portion 16 in a region extending over a half circumference in the circumferential direction of the outer peripheral surface of the electric wire 12 in contact with the inner surface. . In addition, based on the fact that the concave groove 26 has a sufficiently large radius of curvature compared to the radius of the thin wire 28, the fine wire 28 enters and contacts each concave groove 26 formed on the inner surface of the crimping portion 16. I'm hurt.

  Thereby, in the crimping | compression-bonding part 16, the surface area of an inner surface is enlarged by the multiple groove | channels 26, and the contact area to the electric wire 12 is ensured large. Moreover, since the electric wire 12 is composed of the multi-core thin wires 28, even if the inner surface of the crimping portion 16 has an uneven shape, the surface of the electric wire 12 composed of many thin wires 28 is the inner surface of the crimping portion 16. A large contact area can be stably secured by deformation along the shape.

  As a result, it is possible to set a large contact area between the electric wire 12 and the crimping portion 16 without increasing the size of the crimping portion 16 or increasing the diameter of the electric wire 12. The electrical resistance between the parts 16 can be kept low.

  In addition, since the plurality of concave grooves 26 are formed over substantially the entire inner surface of the crimping part 16 as in the present embodiment, bending of the crimping part 16 in the circumferential direction is facilitated. As a result, the caulking operation can be facilitated, and the crimping portion 16 is caulked and deformed along the outer peripheral surface of the electric wire 12 with higher accuracy, thereby further improving the contact area and the electric resistance based thereon. Further reduction of the above can also be achieved.

  By the way, although the manufacturing method of the terminal metal fitting 10 made into the above structures is not specifically limited, For example, it manufactures efficiently by progressive press processing using the base plate 32 for progressive feed shown by FIG. I can do it.

  This progressive base plate 32 has a thin long plate shape or a strip shape before processing. Then, the target terminal fitting 10 is obtained by processing the progressive sheet 32 with a progressive press device, and the process relating to the manufacturing method will be briefly described.

  First, FIG. 5 shows a progressive press state processed through a plurality of progressive press stages in order from right to left. Specifically, such a press stage includes (1) a first stage (not shown) for forming the through holes 18 in the base plate 32 by punching, and (2) a plurality of recesses in the base plate 32 by press processing. A second stage 40 for forming the groove 26; (3) a third stage 42 for forming one side in the width direction of the base plate 32 by pressing (punching); and (4) a base by pressing (punching). A fourth stage 44 for forming the other side in the width direction of the plate 32; (5) a fifth stage 46 for forming the pair of bent portions 24, 24 on the base plate 32 by pressing; and (6) a pair by pressing. A sixth stage 48 for forming the crimped portions 22 and 22; and (7) a seventh stage (not shown) for obtaining the target terminal fitting 10 by cutting the connecting portion 51 in the center in the width direction by punching. Consists of, including .

  As is well known, these first to seventh stages are arranged in series. For example, the base plate 32 is sequentially fed in the length direction by feed pitch control using the through holes 18, and each stage is placed. By sequentially guiding, a progressive press is performed.

  In addition, after penetrating the through hole 18 in the first stage, in the second stage 40, a plurality of concave grooves 26 are formed at a predetermined distance from the through hole 18 to the rear in the feed direction (right in FIG. 5). However, you may make it process these through-holes 18 and the concave groove 26 simultaneously with one press stage. In the embodiment shown in FIG. 5, the groove 26 extends in parallel with the feed direction of the base plate 32 (from right to left in FIG. 5). However, as in another embodiment to be described later, the groove 26 Can be progressively pressed in a state in which the target terminal fitting 10 is arranged in a direction rotated approximately 90 degrees with respect to FIG.

  Further, the third stage 42 and the fourth stage 44 are formed by punching the left and right outer edges in the width direction of the terminal fitting 10 in the shape of a flat plate in order. By processing with two press stages, the left and right outer edges in the width direction of the terminal fitting 10 may be simultaneously punched and formed.

  Further, a pair of caulking portions 22 and 22 are formed by raising both sides in the width direction of the bottom wall portion 20 by the sixth stage 48. The raising processing of the caulking portions 22 and 22 is performed by a plurality of stages. You may make it start up gradually over a period.

  In particular, according to such a manufacturing method of the terminal fitting 10, the base plate 32 is sent to the first stage to form the through hole 18, and the concave groove 26 is formed on the second stage 40, and then the third and second Through the four stages 42 and 44, a punching process is performed on the portion where the concave groove 26 is formed. For example, before the stage for forming the concave groove on the base plate, the base plate is After progressively feeding to multiple stages and performing multiple press processing, it is also possible to form concave grooves on the concave groove forming stage, and then punch the concave groove forming part on another stage is there. In short, in this manufacturing method, after pressing the base plate 32 to form the conductive irregularities (concave grooves 26) on the surface of the base plate 32, the base plate 32 is punched to form the crimping portion 16. It will be. Further, it is possible to simultaneously process the first to seventh stages at a plurality of locations of the progressive sheet 32 while causing the progressive sheet 32 to be sequentially fed to the first to sixth stages. As shown in FIG. 5, it is possible to form the terminal fittings 10 in order from the leading end side (left in FIG. 5) in the feed direction of the base plate 32.

  Thereby, in the terminal metal fitting 10 obtained by progressive pressing, the burr-like overhang | projection in the outer periphery part resulting from forming the unevenness | corrugation for conduction | electrical_connection is completely prevented. That is, the product of the terminal fitting 10 having high-precision dimensions and quality can be obtained only by progressive pressing and without requiring post-processing such as deburring.

  In addition, since the concave groove 26 is press-formed first, and the subsequent stage is subjected to press molding of bending or bending (starting up) along the concave groove 26, the caulking portions 22 and 22 are provided. The press molding of the crimping portion 16 becomes easy, and the molding dimensional accuracy can be improved by pressing.

  In addition, the manufacturing method of the terminal metal fitting 10 of this embodiment is not limited to the thing by such a progressive press, Of course, it is also possible to manufacture by the press work etc. of a single item. Moreover, when manufacturing the terminal metal fitting 10 by progressive press, the specific aspect of progressive press processing is not limited.

  Specifically, as shown in FIG. 6, the single piece of the terminal fitting 10 may be separated from the strip-shaped base plate 50 by a punching press and formed into a single piece. Even in the case of punching alone as described above, the punching of the through hole 18 and the press forming of the concave groove 26 are performed in advance in the process before punching the outer shape of the terminal fitting 10. It is desirable that these processes be performed using a progressive press.

  Further, as shown in FIG. 7, a strip-shaped base plate 52 having a width dimension shorter than twice the entire length of the terminal fitting 10, more specifically, a width dimension of about 1.5 times is adopted. It is also possible to perform progressive press molding in which two molded products (terminal fittings 10) are taken in the width direction of the base plate 52.

  For example, a stage for punching feed pitch holes 54 at a constant interval is provided at a position avoiding the molding region of the terminal fitting 10 at the center in the width direction of the base plate 52, and the progressive pitch is controlled by the feed pitch holes 54. Further, the unnecessary portion 56 between the adjacent terminal fittings 10 is punched out on the same stage as the feed pitch hole 54 or on the next stage, and the concave groove 26 is press-formed on the next separate stage. Next, a punching process for separating both end edges of the crimping portion 16 (the leading edge portion of the caulking portion 22) in the adjacent terminal fittings 10 and 10 is performed, and subsequently, a bent portion with respect to the leading end portion of the caulking portion 22 24 and 24 are press-molded. Further, on the subsequent stage, the crimping portion 16 is bent to raise the caulking portions 22 and 22, and the reinforcing portions 23 and 23 are press-molded. Then, the terminal fitting 10 is obtained by cutting out the tip portion of the connecting portion 14 to form an outer shape.

  According to such a forming method using a progressive press, a wide base plate 52 can be adopted, a plurality of terminal fittings 10 can be taken in the width direction, and the production efficiency of the terminal fitting 10 can be improved. .

  Although the embodiments of the present invention have been described above, the present invention is not limited to the specific descriptions in the embodiments, and various changes, modifications, improvements, and the like based on the knowledge of those skilled in the art. Needless to say, any of these embodiments is included in the scope of the present invention without departing from the gist of the present invention.

  For example, as shown in FIG. 8, the present invention can be applied to a connection terminal fitting 60 for electrically connecting the ends of two electric wires 12 and 12 to each other. Specifically, at least one of the two crimping portions 16, 16 provided on the terminal fitting 60 is provided with an unevenness extending in the length direction of the electric wire 12 on its inner surface (not shown). The present invention can be applied.

  Further, as shown in FIG. 9, a cover crimping portion 62 is further integrally formed as a fixed portion for insulation coating by extending further from the distal end side of the crimping portion 16 that extends from the connecting portion 14 and is integrally formed. Yes. The covering crimping portion 62 includes a pair of caulking portions 64 and 64 that rise from both side edges in the width direction of the bottom wall portion, as in the crimping portion 16, and has a concave groove shape as a whole. Then, it is caulked and fixed to the insulating coating 30 covering the electric wires 12 so as to be in close contact with the outer peripheral surface thereof. Note that the inner surface of the covering crimping portion 62 may be provided with unevenness as fixing unevenness extending in the circumferential direction orthogonal to the length direction of the electric wire 12. By forming such unevenness extending in the circumferential direction, it is possible to advantageously exert a restraining force in the removal direction on the insulating coating 30.

  Furthermore, as shown in FIGS. 10 and 11, the present invention can also be applied to a terminal fitting 66 that is wound around the outer peripheral surface of the electric wire 12 and fixed by pressure bonding. That is, the terminal fitting 66 is integrally formed with a crimping portion 68 having a flat strip shape extending linearly from the connection portion 14. The crimping portion 68 is formed with a plurality of protrusions and recesses 67 extending in the length direction of the electric wire 12 over substantially the entire one surface thereof. In the present embodiment, the unevenness 67 is formed over the entire pressure-bonding portion 68 as a whole with a constant cross-sectional shape having a waveform, and in particular, has a smooth substantially sine waveform cross section.

  The terminal fitting 66 is caulked and fixed so that the electric wire 12 is superimposed on the inner surface of the crimping portion 68 (the surface on which the irregularities 67 are formed), and then the crimping portion 68 is wound around the outer peripheral surface of the electric wire 12. The As a result, the inner surface of the crimping portion 68 with the unevenness 67 is crimped to the outer peripheral surface of the electric wire 12.

  Accordingly, even with such a terminal fitting 66, various effects such as reduction in energization resistance based on an increase in the contact area with the electric wire 12 can be effectively exhibited. In particular, it can be attached by caulking and fixing to an intermediate portion in the longitudinal direction of the electric wire 12.

  Moreover, in the terminal metal fitting 70 shown by FIG. 12, 13, the crimping | crimped part 72 which has the flat strip shape extended linearly from the connection part 14 is integrally formed. A rectangular cut-and-raised piece 74 is formed in the crimping portion 72 in a direction from the substantially central portion in the extending direction toward the connecting portion 14. The cut-and-raised piece 74 is formed by providing a cutting line 76 in a U-shape that opens toward the extending direction of the crimping portion 72 at the center portion in the width direction of the crimping portion 72. The cutting line 76 can be formed by pressing or laser processing.

  Further, a plurality of grooves 26 extending linearly in the vertical direction in FIG. 12, which is the length direction of the electric wire, are formed on the inner surface (side surface of the crimping portion 72 in contact with the electric wire (not shown)). It is formed over. As a result, the inner surface of the crimping part 72 is formed into a concavo-convex shape as a whole, including the part where the cut and raised pieces 74 are formed.

  Further, as shown in FIG. 13, the crimping portion 72 has a tip portion and a cut-and-raised piece 74 with respect to the inner surface side from the center in the extending direction, respectively, at appropriate angles (for example, 30 degrees to 90 degrees). It is bent by press working so that it can be launched at a degree. Thereby, the crimping | compression-bonding part 72 is made into the ditch | groove shape extended in the length direction of an electric wire as a whole.

  Also in the terminal fitting 70 having such a structure, like the terminal fitting 66 shown in FIGS. 10 to 11, it can be crimped and fixed to the outer peripheral surface of the intermediate portion in the length direction of the electric wire. In addition, since a plurality of concave and convex strips (concave grooves 26) extending in the length direction of the electric wire are formed on the inner surface of the crimping portion 72 that is in contact with the outer peripheral surface of the electric wire, the resistance to conduction with the electric wire is reduced. Any of the same effects as those of the above-described embodiment can be effectively exhibited.

  Furthermore, in the present invention, various forms of irregularities formed on the inner surface of the crimping portion of the terminal fitting are employed. For example, as shown in FIG. 14, a plurality of recesses as conductive concavities and convexities extending in the length direction of the electric wire 12 at different positions in the length direction of the electric wire 12 on the inner surface of the concave groove of the crimping portion 16. You may form the groove | channel 26 and the circumferential groove | channel 80 as the uneven | corrugated uneven | corrugated for multiple extending | stretching extended in the circumferential direction of the electric wire 12. FIG. By forming such a circumferential groove 80, it is possible to improve the fixing force in the direction in which the electric wire 12 is pulled out with respect to the terminal fitting 82. In this specific example, in the region where the terminal fitting 82 is brought into contact with the outer peripheral surface of the electric wire 12, regions where the peripheral grooves 80 are formed are provided on both sides of the region where the concave groove 26 is formed in the length direction of the electric wire 12. It has been. As is clear from this, at least one circumferential groove 80 and one concave groove 26 are alternately formed in the length direction of the electric wire 12.

  Further, as shown in FIG. 15, in the terminal fitting 84, the concave groove 26 that forms the concavity and convexity for conduction according to the present invention extending in the length direction of the electric wire 12 in the region brought into contact with the outer peripheral surface of the electric wire 12. May be formed, and a lattice-shaped unevenness 86 or the like may be formed in another region. In the figure, reference numeral 88 denotes a concave groove as a concavity and convexity for fixing that extends in the circumferential direction of the electric wire 12 and is formed on the inner surface of the coating crimping part 62 that is caulked and fixed to the insulating coating layer 30.

  Furthermore, the present invention can be similarly applied to a terminal fitting fixed to a single-core electric wire by caulking or the like. In that case, for example, as shown in FIG. 16, for example, an uneven strip extending in the length direction (direction perpendicular to the paper surface) of the single-core electric wire 90 with a relatively smooth continuous wave-shaped cross-sectional shape. A terminal fitting having a crimping portion 94 having an inner surface 92, or a convex extending in the length direction of the single-core electric wire 90 with a mountain-shaped cross section having a sharp projecting corner as shown in FIG. A terminal fitting or the like having a crimping portion 98 provided with a plurality of uneven surfaces of the strip 96 can be adopted.

  In such a terminal fitting, the contact area on the concavo-convex surface can be more effectively improved and secured with respect to the outer peripheral surface of the single-core electric wire 90.

  Further, in the above embodiment, a progressive press using the progressive feed base plate 32 is adopted when manufacturing the terminal fitting, but the present invention is not limited to this. For example, a plurality of presses are provided at appropriate locations on the base plate. To form one or more terminal fittings, or press fitting (punching) as necessary for fittings with through holes and concave grooves formed by casting. It is also possible to form terminal fittings.

The top view of the terminal metal fitting as one Embodiment of this invention. The expansion explanatory view of the lower end surface in Drawing 1 of the terminal metal fitting shown in Drawing 1. The top view of the electric wire with a crimp terminal to which the terminal metal fitting shown by FIG. 1 was attached. Explanatory explanatory drawing of the IV-IV cross section in FIG. Plane | planar explanatory drawing of the base plate for demonstrating the manufacturing process by the progressive press of the terminal metal fitting shown by FIG. Plane explanatory drawing of the base plate for demonstrating an example of another manufacturing method of the terminal metal fitting shown by FIG. Plane explanatory drawing of the base plate for demonstrating an example of another manufacturing method of the terminal metal fitting shown by FIG. The top view of the electric wire with a crimp terminal to which the terminal metal fitting as another one embodiment of the present invention was attached. The top view of the electric wire with a crimp terminal to which the terminal metal fitting as another embodiment of this invention was attached. The top view of the electric wire with a crimp terminal to which the terminal metal fitting as another embodiment of this invention was attached. The enlarged view of the XI-XI cross section in FIG. The top view of the terminal metal fitting as another one Embodiment of this invention. XIII-XIII sectional drawing in FIG. Plane explanatory drawing which shows the terminal metal fitting as another one Embodiment of this invention. Plane explanatory drawing which shows the terminal metal fitting as another one Embodiment of this invention. The transverse cross section of the electric wire with a crimp terminal to which the terminal metal fitting as another embodiment of the present invention was attached. The transverse cross section of the electric wire with a crimp terminal to which the terminal metal fitting as another embodiment of the present invention was attached.

Explanation of symbols

10: terminal fitting, 12: electric wire, 16: crimping part, 26: concave groove

Claims (9)

A crimp terminal that is crimped to the outer peripheral surface of the electric wire,
A plurality of conductive irregularities extending in the same direction as the electric wire are formed on the inner surface of the crimping portion to be crimped to the outer peripheral surface of the electric wire in a region extending over a half circumference in the circumferential direction of the electric wire. Crimp terminal to be used.   On the inner surface of the crimping portion, a locking unevenness extending in the circumferential direction of the electric wire is formed in a region different from the region where the conductive unevenness is formed. The crimp terminal according to claim 1, wherein the unevenness for stopping comes into contact.   The at least one each of the unevenness | corrugation for latching and the said unevenness | corrugation for conduction | electrical_connection extended in the circumferential direction of this electric wire are alternately formed in the length direction of this electric wire in the contact part to the outer peripheral surface of the said electric wire. Or the crimp terminal as described in 2.   The electric wire is covered with an insulation coating and the outer peripheral surface is covered, and the crimping portion is crimped to an exposed portion of the electric wire partially exposed from the insulation coating in the length direction of the electric wire. And an insulating coating fixing portion that is crimped to the outer peripheral surface of the insulating coating that covers the electric wire, and an inner peripheral surface of the insulating coating fixing portion that extends in the circumferential direction of the electric wire. The crimp terminal as described in any one of Claims 1 thru | or 3 with which the unevenness | corrugation is formed.   The crimping portion includes a bottom wall portion and a pair of caulking portions rising from both sides in the width direction of the bottom wall portion, and the conductive irregularities are formed on at least the bottom wall portion of the crimping portion. The crimp terminal as described in any one of Claims 1 thru | or 4. A wire with a crimp terminal to which the crimp terminal according to any one of claims 1 to 5 is fixed,
The electric wire with a crimp terminal, wherein the crimp portion of the crimp terminal is crimped to the electric wire, and the conductive irregularities are in contact with the outer peripheral surface of the electric wire over a half circumference.   The electric wire is a multi-core electric wire in which a plurality of thin wires are bundled in parallel, and the concave portion of the concavo-convex for conduction has an arcuate curved concave cross section having a larger radius of curvature than the fine wire of the multi-core electric wire. The electric wire with a crimp terminal according to claim 6. When manufacturing the crimp terminal according to any one of claims 1 to 5 by punching the base plate,
Forming the concavity and convexity on the surface of the base plate by pressing the base plate, and then forming the pressure-bonding portion by punching the base plate. The manufacturing method of the crimp terminal.   A long plate-shaped progressive plate is adopted as the blank, and the progressive plate is fed to a plurality of stages to perform a multi-stage press process and a press process to form the conductive irregularities. The manufacturing method of the crimp terminal of Claim 8 which punches with respect to the part in which this unevenness | corrugation for conduction | electrical_connection was formed in another stage after this stage.

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