Electrical cable equipped with connection

Abstract

To comprise: an electrical conductor (10) comprising a core conductor (11) comprising a bundle of element wires and a sheath (12) that covers the core conductor (11) over a circumferential direction and includes an exposed section (11a) of the core conductor in which part of the core conductor (11) is exposed over the circumferential direction; and a connector (20) comprising a core conductor connection section (22) comprising a flat surface (22a) on which the exposed section (11a) of the core conductor is arranged and in which a bonding section (11b) of the exposed section (11a) of the core conductor is ultrasonically bonded to the flat surface (22a) of a bonded section (22b) of the core conductor connection section (22).Between the bonding section (11b) and an end face of the sheathing (12), the exposed section (11a) of the core conductor includes a compressed depression (14) which is compressed in the direction of the flat surface (22a) of the core conductor connection section (22) and is recessed to a position that is lower than the height of the bonding section (11b) from the flat surface (22a) of the core conductor connection section (22).

Description

Area

[0001] The present invention relates to an electrical cable equipped with a terminal. background

[0002] Regarding a method for manufacturing a terminal-equipped electric wire, a conventionally known technique for physically and electrically connecting an electric wire and a terminal fitting is ultrasonic bonding, in which ultrasonic vibration is applied to an exposed portion of a core wire of the electric wire and a connecting portion of a core wire of the terminal fitting while applying pressure thereto. In this ultrasonic bonding, while the exposed portion of the core wire and the connecting portion of the core wire are clamped and pressed between two punches, ultrasonic vibration, whose vibration direction is along the axial direction of the exposed portion of the core wire, is applied to the exposed portion of the core wire from a punch (vibration punch).Such pressing and ultrasonic vibration cause the element wires of the exposed portion of the core wire to be ultrasonically bonded to each other, and cause the element wire of the exposed portion of the core wire and the connecting portion of the core wire to be ultrasonically bonded to each other. Thus, the electric wire and the terminal fitting are formed as a terminal-equipped electric wire. This type of terminal-equipped electric wire is disclosed, for example, in the following Patent Literature 1 to Patent Literature 5. Citation listPatent literature Patent Literature 1: Japanese Patent Application Laid-Open No. 2006-172917 Patent Literature 2: Japanese Patent Application Laid-Open No. 2014-107104 Patent Literature 3: Japanese Patent Application Laid-Open No. 2014-211952 Patent Literature 4: Japanese Patent Application Laid-Open No. 2019-040778 Patent Literature 5: Japanese Patent Application Laid-Open No. 2019-145263 SummaryTechnical task

[0003] The exposed portion of the core wire of the electric wire is squeezed by the vibration punch along with the pressure in a direction toward the core wire connection portion side. Accordingly, the height of the exposed portion of the core wire gradually decreases from the core wire connection portion to the portion squeezed by the vibration punch. For this reason, in the exposed portion of the core wire, when the vibration punch reciprocating in the vibration direction collides with the incline changing in height, an element wire at the incline may cause an element wire breakage.

[0004] In view of the foregoing, it is an object of the present invention to provide a terminal-equipped electric wire in which an element wire breakage is prevented from occurring. Solution to the task

[0005] A terminal-equipped electric wire according to the present invention comprises an electric wire including a core wire including an element wire bundle and a cover covering the core wire over a circumferential direction, the electric wire including a core wire exposed portion in which a part of the core wire is exposed over the circumferential direction;and a terminal fitting comprising a core wire connecting portion having a flat surface on which the exposed portion of the core wire is disposed, wherein a bonding portion of the exposed portion of the core wire is ultrasonically bonded to the flat surface of a bonded portion of the core wire connecting portion, wherein the exposed portion of the core wire includes a compressed recess between the bonding portion and an end face of the cover, wherein the compressed recess is compressed toward the flat surface of the core wire connecting portion and is depressed to a position lower than a height of the bonding portion from the flat surface of the core wire connecting portion;

[0006] The terminal-equipped electric wire according to the present invention includes a compressed recess between the bonding portion of the exposed portion of the core wire and the end face of the covering. The compressed recess is recessed to a position lower than the height of the bonding portion above the flat surface of the core wire connecting portion.Therefore, when a tool used for ultrasonic bonding reciprocates in the axial direction of the exposed portion of the core wire while applying ultrasonic vibration and pressure to the bonding portion, the bonding portion of the exposed portion of the core wire can be ultrasonically bonded to the flat surface of the bonded portion of the core wire connecting portion to form the terminal-equipped electric wire without colliding with a portion between the bonding portion of the exposed portion of the core wire and the end face of the cover. Therefore, the terminal-equipped electric wire according to the present invention can prevent element wire breakage from occurring at the exposed portion of the core wire. Short description of the drawings Fig. 1 is an explanatory view illustrating a terminal-equipped electric wire according to an embodiment. Fig. 2 is an explanatory view for describing a core line processing step. Fig. 3 is an explanatory view for describing a bonding step. Fig. 4 is an explanatory view illustrating a manufacturing facility according to the embodiment. Description of embodiments

[0007] Hereinafter, an embodiment of a terminal-equipped electric wire according to the present invention will be described in detail with reference to the drawings. Note that this invention is not limited to the embodiment. [Embodiment]

[0008] Hereinafter, an embodiment of an electric cable equipped with a cable according to the present invention will be described with reference to Fig. 1 to 4 described.

[0009] The reference number 1 in Fig. 1 denotes an electric wire equipped with a terminal in the present embodiment.

[0010] The electrical line 1 equipped with a connector comprises an electrical line 10 and a connector 20 which are physically and electrically connected to each other ( Fig. 1).

[0011] The electric wire 10 comprises a core wire 11 and a sheath 12. The core wire 11 is covered with the tubular sheath 12 from the outer peripheral surface side over the circumferential direction ( Fig. 1 to 3). The core wire 11 is formed as an element wire bundle in which a plurality of element wires 13, each made of a conductive metal wire material, are bundled. The sheath 12 is formed of an insulating resin material that covers the core wire 11 from the outer peripheral surface side.

[0012] The electric wire 10 includes a core wire exposed portion 11a in which a part of the core wire 11 is exposed over the circumferential direction ( Fig. 1 to 3). For example, in the electric wire 10, the covering 12 of the electric wire 10 is subjected to processing such as peeling the end of the covering 12 in the circumferential direction at a terminal (hereinafter referred to as an "electric wire terminal") 10a of the electric wire 10. With this processing, the core wire exposed portion 11a exposed over the entire circumference is provided at the electric wire terminal 10a. The core wire exposed portion 11a of the electric wire terminal 10a protrudes from the annular end face of the covering 12 and is ultrasonically bonded to the terminal fitting 20 at a location away from the end face of the covering 12 toward the free end side. For example, in the electric wire 10, the covering 12 is peeled in the circumferential direction at the center of the axis of the electric wire 10.With such processing, the exposed portion 11a of the core wire exposed over the entire circumference is provided between the two annular end faces of the sheath 12 at the center of the axis of the electric wire 10. The exposed portion 11a of the core wire in the center of the electric wire 10 is ultrasonically bonded to the terminal fitting 20 at a location between the two end faces of the sheath 12 and away from each end face.

[0013] In the terminal-equipped electric wire 1, the terminal fitting 20 is attached to the exposed portion 11a of the core wire at the terminal or in the middle of the electric wire 10. The electric wire 10 illustrated here includes the exposed portion 11a of the core wire at the electric wire terminal 10a. Accordingly, in this terminal-equipped electric wire 1, the terminal fitting 20 is attached to the exposed portion 11a of the core wire at the electric wire terminal 10a.

[0014] The terminal piece 20 is formed from a conductive material, such as metal. The terminal piece 20 is formed into a predetermined shape, for example, by press forming, such as bending or cutting a metal plate that serves as the starting material.

[0015] The connector 20 comprises a terminal connecting portion 21 which is physically and electrically connected to a counterpart (not shown) ( Fig. 1 and Fig. 3). The terminal connecting portion 21 can be physically and electrically connected to the mating terminal in any form. For example, the terminal connecting portion 21 can be formed into a flat plate shape having a through hole (not shown) and can be screwed and fixed to the terminal connecting portion of the mating terminal fitting by screwing a female thread member to a male thread member inserted through the through hole of the terminal connecting portion 21 and a through hole of the terminal connecting portion of the mating terminal fitting (not shown). In another example, one of the terminal connecting portion 21 of the terminal fitting 20 and the terminal connecting portion of the mating terminal fitting can be formed into a female terminal shape, and the other of them can be formed into a male terminal shape.With this configuration, the plug terminal-shaped terminal connecting portion can be inserted into the socket terminal-shaped terminal connecting portion, and these terminal connecting portions can be assembled to each other.

[0016] The terminal 20 includes: a flat surface 22a on which the exposed portion 11a of the core wire of the electric wire 10 is arranged; and a core wire connecting portion 22 that physically and electrically connects the exposed portion 11a of the core wire to the flat surface 22a ( Fig. 1 and Fig. 3). In the core wire connecting portion 22, a bonding portion 11b of the exposed portion 11a of the core wire is ultrasonically bonded to the flat surface 22a of a bonded portion 22b. The core wire connecting portion 22 shown here is formed in a flat plate shape.

[0017] The connector 20 comprises a sheath holder 23 which holds the sheath 12 of the electrical line connection 10a ( Fig. 1 and Fig. 3). The sheath holder 23 holds the sheath 12, for example, by swaging and crimping a pair of cylinder pieces 23a to the sheath 12 of the electrical wire terminal 10a.

[0018] The terminal fitting 20 shown here is formed to include: a flat plate-shaped piece including the terminal connecting portion 21, the core wire connecting portion 22, and a bottom 23b of the sheath holder 23; and the pair of cylinder pieces 23a protruding from the bottom 23b of the sheath holder 23. However, the terminal fitting 20 may be formed in any shape, such as an intersecting shape obtained by bending the terminal fitting 20 to have a portion on the terminal connecting portion 21 side and a portion on the core wire connecting portion 22 and the sheath holder 23 side.

[0019] The above-described electrical cable 1 equipped with a connector is manufactured using a manufacturing plant 101 ( Fig. 4) and a manufacturing process using the same.

[0020] The method for manufacturing the terminal-equipped electric wire 1 includes: an electric wire arranging step of arranging the electric wire terminal 10a on the flat surface 22a of the core wire connecting portion 22 and the bottom 23b of the cover holder 23; an electric wire holding step of swaging and crimping the pair of cylinder pieces 23a of the cover holder 23 to the cover 12 of the electric wire terminal 10a; and a bonding step of ultrasonically bonding the bonding portion 11b of the core wire exposed portion 11a and the bonded portion 22b of the flat surface 22a of the core wire connecting portion 22.The terminal-equipped electric wire 1 manufacturing plant 101 includes a crimping device 110 for performing the electric wire arranging step and the electric wire holding step, and an ultrasonic bonding device 120 for performing the bonding step (. Fig. 4).

[0021] The crimping device 110 includes a pair of punches (not shown) for swaging and crimping the sheath holder 23 to the sheath 12 of the electrical wire terminal 10a while squeezing and pressing the bottom 23b of the sheath holder 23 and the pair of cylinder pieces 23a.

[0022] The terminal 20 is placed on a die. The electrical wire terminal 10a is placed on the terminal 20 placed on one die. The other die is a die that can reciprocate to be brought closer to or away from the one die. The other die is attached to a drive unit (not shown) that causes the reciprocation. The other die is brought closer to the one die to swage and crimp the sheath holder 23 onto the sheath 12 of the electrical wire terminal 10a.

[0023] In the electric wire arranging step, the terminal 20 is arranged on one die, and the electric wire terminal 10a is arranged on the flat surface 22a of the core wire connecting portion 22 and the bottom 23b of the cover holder 23 in the terminal 20. In the electric wire holding step, while the other die is brought closer to one die, the pair of cylinder pieces 23a of the cover holder 23 are wound around the cover 12 of the electric wire terminal 10a and swaged and crimped simultaneously by the other die. In the electric wire arranging step shown here, the bonding portion 11b of the core wire exposed portion 11a is arranged on the flat surface 22a of the bonded portion 22b of the core wire connecting portion 22.Then, in the electric wire holding step, the cover holder 23 is swaged and crimped to the cover 12 of the electric wire terminal 10a in a state in which the bonding portion 11b of the core wire exposed portion 11a is disposed on the bonded portion 12b of the core wire connecting portion 22.

[0024] Here, the exposed portion 11a of the core wire is ultrasonically bonded to the terminal 20 that holds the electric wire 10 with the sheath holder 23. The ultrasonic bonding device 120 includes a first punch 121 and a second punch 122 that apply ultrasonic vibration to the bonding portion 11b and the bonded portion 22b while squeezing and pressing the bonding portion 11b of the exposed portion 11a of the core wire and the bonded portion 22b of the core wire connecting portion 22 ( Fig. 3).

[0025] The bonded portion 22b of the core wire connecting portion 22 is arranged on the first die 121. The first die 121 shown here includes a contact portion 121a having a plurality of projections and recesses, and the bonded portion 22b is arranged on the contact portion 121a ( Fig. 3). The contact portion 121a is, for example, a plurality of projections and recesses formed by knurling performed on the first punch 121.

[0026] The second punch 122 is a punch that can reciprocate to be brought closer to or away from the first punch 121. The second punch 122 is attached to a drive unit (not shown) that causes the reciprocation. By bringing the second punch 122 closer to the first punch 121, it comes into contact with the bonding portion 11b of the core wire exposed portion 11a on the bonded portion 22b of the core wire connecting portion 22, and the bonding portion 11b and the bonded portion 22b are squeezed and pressed between the first punch 121 and the second punch 122. The second stamp 122 shown here includes a contact portion 122a similar to the contact portion 121a of the first stamp 121, and the contact portion 122a is brought into contact with the bonding portion 11b of the exposed portion 11a of the core line ( Fig. 3).

[0027] In the bonding step, the other flat surface of the bonded portion 22b of the core wire connecting portion 22 is placed on the first die 121. In this state, the bonding portion 11b of the core wire exposed portion 11a is placed on the flat surface 22a of the bonded portion 22b of the core wire connecting portion 22. Therefore, in this bonding step, the bonded portion 22b and the bonding portion 11b are ultrasonically bonded to each other by the ultrasonic vibration applied to the second punch 122, while the bonded portion 22b and the bonding portion 11b are squeezed and pressed by the first punch 121 brought into contact with the other flat surface of the bonded portion 22b and the second punch 122 brought into contact with the bonding portion 11b of the core wire exposed portion 11a.The ultrasonic bonding apparatus 120 includes an ultrasonic vibrator (not shown) and applies an ultrasonic vibration from the ultrasonic vibrator to the second punch 122.

[0028] Here, ultrasonic vibration is applied along the axial direction of the core wire exposed portion 11a to the second punch 122. In the bonding step, the bonding portion 11b is compressed to a position lower than the height of the core wire 11, corresponding to the core wire diameter thereof measured from the flat surface 22a of the core wire connecting portion 22, by the pressure applied to the bonding portion 11b between the first punch 121 and the second punch 122. Therefore, in the bonding step, the height of the core wire exposed portion 11a gradually decreases from the flat surface 22a of the core wire connecting portion 22 from the end face of the covering 12 of the electric wire terminal 10a to the bonding portion 11b.That is, in the bonding step, the second punch 122 compresses the bonding portion 11b while reciprocating in the vibration direction of the ultrasonic vibration to create a slope on the exposed portion 11a of the core wire from the end face of the cover 12 to the bonding portion 11b. Therefore, in this bonding step, the second punch 122, reciprocating in the axial direction of the exposed portion 11a of the core wire, may collide with the slope. When the second punch 122 collides with the slope, the element wires 13 may be cut off at the surface of the slope.

[0029] In view of the foregoing, a compressed recess 14 is provided in advance before proceeding to the bonding step between the bonding portion 11b of the exposed portion 11a of the core wire and the end face of the sheath 12 ( Fig. 2). The compressed recess 14 is a recess located on the second punch 122 side in the bonding step and is more compressed than the bonding portion 11b after ultrasonic bonding in the same compression direction as the compression direction for the bonding portion 11b at the time of ultrasonic bonding. As a result, the terminal-equipped electric wire 1 includes, between the bonding portion 11b of the core wire exposed portion 11a and the end face of the cover 12, the compressed recess 14 compressed toward the flat surface 22a of the core wire connecting portion 22 and recessed to a position lower than the height of the bonding portion 11b from the flat surface 22a of the core wire connecting portion 22 ( Fig. 1 and Fig. 3).

[0030] To prevent the second punch 122, which reciprocates in the vibration direction of the ultrasonic vibration, from coming into contact with a portion further to the cover 12 side than the bonding portion 11b of the core wire exposed portion 11a, the compressed groove 14 between the bonding portion 11b of the core wire exposed portion 11a and the end face of the cover 12 is formed as a groove having a position and shape that can avoid the reciprocating second punch 122. If the configuration with only one compressed groove 14 cannot avoid the reciprocating second punch 122, a plurality of compressed grooves may be provided.The compressed recess 14 shown here is a single groove-shaped recess having an arcuate bottom and is continuously connected to one end of the bonding portion 11b on the side of the sheath 12.

[0031] The method for manufacturing the terminal-equipped electric wire 1 includes a core wire processing step of forming the compressed recess 14 on the exposed portion 11a of the core wire. The manufacturing plant 101 for the terminal-equipped electric wire 1 includes a core wire forming device 130 for performing the core wire processing step ( Fig. 4). For example, the core wire processing step may be performed on the electric wire alone before the electric wire placement step, or may be performed on the electric wire 10 in a state where it is held by the terminal 20 before the bonding step is performed after the electric wire holding step is completed. Here, the core wire processing step performed on the electric wire alone will be described.

[0032] The core line forming device 130 includes a first pressing tool 131 and a second pressing tool 132, which form the compressed recess 14 on the exposed portion 11a of the core line while squeezing and pressing the exposed portion 11a of the core line ( Fig.2). In the core wire forming apparatus 130, the exposed portion 11a of the core wire is placed on the first pressing die 131, and while the first pressing die 131 and the second pressing die 132 are brought closer to each other, the compressed recess 14 is formed on the exposed portion 11a of the core wire by a protrusion 132a provided on the second pressing die 132. At least one protrusion 132a is provided in accordance with the number of the compressed recesses 14.

[0033] For example, the first pressing die 131 includes a semi-arc-shaped wall surface along the outer peripheral surface of the core wire exposed portion 11a, and the core wire exposed portion 11a is placed on the wall surface. The second pressing die 132 includes a wall surface to be brought into contact with the outer peripheral surface of the core wire exposed portion 11a; and the protrusion 132a protruding from a part of the wall surface. For example, the second pressing die 132 may include the wall surface formed in a semi-arc shape and only form the compressed recess 14 at the core wire exposed portion 11a using the protrusion 132a.Alternatively, in the second pressing tool 132, not only can the compressed recess 14 be formed in the exposed portion 11a of the core wire by the protrusion 132a, but also, for example, the wall surface of the second pressing tool 132 can be flat to press the bonding portion 11b to a predetermined position with the wall surface. The second pressing tool 132 shown here includes the latter flat wall surface. The second pressing tool 132 shown here is a tool that can reciprocate to be brought closer to or away from the first pressing tool 130. The second pressing tool 132 is attached to a drive unit (not shown) that effects the reciprocation.

[0034] In the core wire processing step, the exposed portion 11a of the core wire is placed on the semi-arc-shaped wall surface of the first pressing die 131, and the second pressing die 132 is brought closer to the exposed portion 11a of the core wire. Accordingly, in the core wire processing step, the second pressing die 132 first comes into contact with the exposed portion 11a of the core wire on the first pressing die 131 from the projection 132a, and the exposed portion 11a of the core wire is pressed by the projection 132a, while the exposed portion 11a of the core wire is squeezed and pressed between the projection 132a and the first pressing die 131 to form the compressed recess 14.

[0035] Therefore, in the electric wire arranging step of the present embodiment, the exposed portion 11a of the core wire is arranged with the compressed recess 14 facing upward relative to the flat surface 22a of the core wire connecting portion 22 of the die-mounted terminal 20. Then, in the electric wire holding step, the cover holder 23 is swaged and crimped onto the cover 12 of the electric wire terminal 10a with the compressed recess 14 facing upward.

[0036] Next, in the bonding step of the present embodiment, when the bonded portion 22b of the core wire connecting portion 22 is placed on the first punch 121, the compressed recess 14 of the core wire exposed portion 11a faces upward and is placed on the second punch 122 side. Accordingly, in this bonding step, the bundled portion 22b and the bonding portion 11b are ultrasonically bonded to each other by the ultrasonic vibration applied to the second punch 122, while the bonded portion 22b of the core wire connecting portion 22 and the bonding portion 11b of the core wire exposed portion 11a are squeezed and pressed by the first punch 121 and the second punch 122.At this time in this bonding step, the second punch 122, which reciprocates in the vibration direction of the ultrasonic vibration, does not collide with a portion between the bonding portion 11b of the core wire exposed portion 11a and the end face of the cover 12. Thus, the occurrence of element wire buckling of the element wire 13 of the core wire exposed portion 11a can be prevented. Therefore, in this bonding step, the pressing force on the bonded portion 22b and the bonding portion 11b from the first punch 121 and the second punch 122 can be increased compared to that in the conventional case. As a result, it is possible to perform ultrasonic bonding in which the portion between the bonded portion 22b and the bonding portion 11b and between the element wires 13 of the bonding portion 11b are brought into closer contact with each other.Therefore, in this bonding step, the time required for ultrasonic bonding can be made shorter than in the conventional case. As described above, the terminal-equipped electric wire 1 of the present embodiment is produced by this bonding step in a shorter time than the conventional terminal-equipped electric wire, while preventing the occurrence of element wire breakage. List of reference symbols 1 electrical cable equipped with a connector 10 electrical cables 11 Core line 11a exposed section of the core line 11b Bonding section 12 Sheathing 13 Element wire 14 compressed depression 20 connector 22 Core line connection section 22a flat surface 22b bonded section QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] JP 2006-172917

[0002] JP 2014-107104

[0002] JP 2014-211952

[0002] JP 2019-040778

[0002] JP 2019-145263

[0002]

Claims

[1] Electrical cable equipped with a connector, comprising: an electric wire comprising a core wire including an element wire bundle and a cover covering the core wire over a circumferential direction, the electric wire comprising an exposed portion of the core wire in which a part of the core wire is exposed over the circumferential direction; and a connector comprising a core wire connecting portion having a flat surface on which the exposed portion of the core wire is disposed, wherein a bonding portion of the exposed portion of the core wire is ultrasonically bonded to the flat surface of a bonded portion of the core wire connecting portion, wherein the exposed portion of the core wire comprises a compressed recess between the bonding portion and an end face of the cover, the compressed recess being compressed toward the flat surface of the core wire connecting portion and being recessed to a position lower than a height of the bonding portion from the flat surface of the core wire connecting portion. [2] The terminal-equipped electric wire according to claim 1, wherein the compressed recess is continuously connected to one end of the bonding portion on the cover side. [3] The terminal-equipped electric wire according to claim 1 or 2, wherein the bonding portion is compressed to a position lower than a height of the core wire corresponding to a diameter of the core wire, the height being measured from the flat surface of the core wire connecting portion.

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