Terminal structure of shield electric wire, electric wire with terminal, and electric wire with connector

Abstract

To provide a terminal structure of a shield electric wire that has a high tensile strength of a ferrule, has a compact terminal structure formed easily, and an electric wire with a terminal and an electric wire with a connector including the same.SOLUTION: A terminal structure of a shield electric wire has a core part, a shield layer, and a casing, and the terminal structure of a shield electric wire comprises: a ferrule that has a wave-shaped cylindrical part located between the core part and an exposed portion of the shield layer; a sleeve that has a sleeve barrel part fixed and arranged at a position facing an outer peripheral surface of the cylindrical part, while sandwiching the exposed portion with the cylindrical part; and a holder that includes a holder barrel part and a holder contact part extending radially outward from an end of the holder barrel part on the side of a cylindrical part base, wherein the holder barrel part is located between the cylindrical part and the core part located inside the exposed portion, and holds a pressure-fixation state of the cylindrical part to the sleeve barrel part with the exposed portion therebetween, and the holder contact part is located closer to a shield electric wire leading end than the cylindrical part, and holds a contact state of the cylindrical part with a casing exposed end with the exposed portion therebetween.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present disclosure relates to a terminal structure for a shielded electric wire, an electric wire with a terminal, and an electric wire with a connector. [Background technology]

[0002] BACKGROUND ART Conventionally, shielded electric wires have been used in electric wires used in, for example, wire harnesses in automobiles in order to prevent leakage of electromagnetic waves to the outside or to suppress the influence of electromagnetic waves from the outside on the electric wires.

[0003] As such a shielded electric wire, for example, a shielded electric wire has been proposed in which a shield layer made of a braided wire is formed on the outer periphery of an insulated coated electric wire, and an outer sheath is formed on the outer periphery of this shield layer. When a terminal or the like is connected to the tip of such a shielded electric wire to form a connector, it is necessary to form a terminal structure for grounding the shield layer.

[0004] 9A and 9B are explanatory diagrams showing the steps for forming a conventional terminal structure. First, as shown in Fig. 9A and Fig. 9B, the outermost outer sheath 103 of the shielded electric wire 100 is cut and removed over a predetermined length from the end, exposing the shield layer 105 of the inner braided wire.

[0005] 9(c), the shield layer 105 is cut to a predetermined length to expose the internal core portion 107. That is, a predetermined length of the shield layer 105 is exposed from the tip of the outer jacket 103, and a predetermined length of the core portion 107 is exposed from the tip of the shield layer 105. The core portion 107 is an electric wire with an insulating coating on a conductor.

[0006] Next, as shown in Fig. 9(d), a predetermined length of inner ferrule 109 is placed near the end of the outer jacket 103. The inner ferrule 109 is a ring-shaped metal member. After that, as shown in Fig. 9(e), the shielding layer 105 exposed from the outer jacket 103 is folded back toward the outer jacket 103 (toward the inner ferrule 109). As a result, the inner ferrule 109 is covered with the shielding layer 105.

[0007] 9(f), the outer ferrule 113 is disposed on the outer periphery of the shield layer 105. The outer ferrule 113 is a metal annular member similar to the inner ferrule 109, and has an inner diameter larger than the outer diameter of the inner ferrule 109. In this state, by compressing the outer ferrule 113 from the periphery, the inner ferrule 109 and the outer ferrule 113 can be crimped together with the shield layer 105 sandwiched between them.

[0008] Thereafter, a terminal is connected to the core portion 107 and accommodated in the connector housing. At this time, the outer ferrule 113 is brought into contact with a metal member disposed in the connector housing, and the metal member is connected to a ground wire, thereby grounding the shield layer of the shielded electric wire 100.

[0009] However, in the conventional terminal structure shown in Fig. 9 , the inner ferrule 109 and the outer ferrule 113 are fixed to the folded portion of the shield layer 105, which is made of a braided wire that easily expands and contracts. Therefore, the inner ferrule 109 and the outer ferrule 113, which are fixed while sandwiching the braided wire, follow the expansion and contraction of the shield layer 105 and are therefore not sufficiently fixed in the axial direction of the shielded wire 100 and tend to move easily. This raises concerns about a decrease in the tensile strength of these ferrules relative to the shielded wire 100. Furthermore, because the inner ferrule 109 and the outer ferrule 113, which are fixed while sandwiching the shield layer 105, are formed on the outer sheath 103 of the shielded wire 100, they tend to significantly protrude from the outer periphery of the shielded wire 100, resulting in an increase in the size of the structure in question. Furthermore, because the required length of the shield layer 105 increases by the amount of folding, stripping cannot be performed in one go. In other words, before folding back the shield layer 105, it is necessary to expose the shield layer 105 by stripping, and after folding back the shield layer 105, it is necessary to perform stripping to expose the conductor from the core portion 107, so there is room for improvement in terms of ease of forming the terminal structure. [Prior art documents] [Patent documents]

[0010] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-51141 [Patent Document 2] Patent Publication No. 2021-182467 Summary of the Invention [Problem to be solved by the invention]

[0011] An object of the present disclosure is to provide a terminal structure for a shielded electric wire that has a high tensile strength of a ferrule relative to the shielded electric wire, has a compact structure, and is easy to form, as well as a terminal-equipped electric wire and a connector-equipped electric wire that include the same. [Means for solving the problem]

[0012] [1] A terminal structure of a shielded electric wire having a core portion in which a conductor is covered with an insulating layer, a shielding layer arranged on the outer periphery of the core portion, and an outer sheath covering the outer periphery of the shielding layer, the terminal structure comprising a cylindrical portion having an inner diameter larger than the outer diameter of the core portion and extending in a wave shape, the cylindrical portion having an exposed portion of the shielding layer exposed when a predetermined length of the outer sheath is peeled off, a ferrule positioned between the cylindrical portion and the core portion, a sleeve body portion having an inner diameter larger than the outer diameter of the shielded electric wire, the sleeve body portion being fixedly arranged at a position facing the outer peripheral surface of the cylindrical portion in a state where the exposed portion of the shielding layer is sandwiched between the cylindrical portion, and a ring-shaped sleeve having an outer diameter smaller than the inner diameter of the cylindrical portion. and a holder abutment portion extending radially outward from an end of the holder body portion on the cylindrical portion base side, wherein the holder body portion is located between the inner peripheral surface of the cylindrical portion and a portion of the outer peripheral surface of the core portion located on the inner peripheral surface side of the exposed portion of the shielding layer, and holds the cylindrical portion in a state where it is pressed and fixed to the sleeve body portion via the exposed portion of the shielding layer, and the holder abutment portion is located closer to the tip of the shielded electric wire than the cylindrical portion and holds the end side of the cylindrical portion in a state where it abuts against the exposed end of the outer jacket via the exposed portion of the shielding layer. [2] The sleeve further includes a sleeve abutment portion extending radially inward from the end of the sleeve body on the tubular portion end side, and the holder abutment portion maintains the end side of the tubular portion in abutment against the exposed end of the outer jacket and the sleeve abutment portion via the exposed portion of the shielding layer, in the terminal structure of the shielded electric wire described in [1] above. [3] An electric wire with terminal having the terminal structure of the shielded electric wire described in [1] or [2] above, wherein a predetermined length of the insulating layer is peeled off from the tip of the core portion, and the portion of the conductor exposed by the peeling is connected to a terminal. [4] An electric wire with a connector in which the electric wire with terminal described in [3] above is accommodated in a connector housing, and a metal member is arranged in the connector housing over an area facing the terminal and the ferrule, and the ferrule and the metal member are electrically connected. [Effects of the Invention]

[0013] According to the present disclosure, it is possible to provide a terminal structure for a shielded electric wire that has a high tensile strength of the ferrule relative to the shielded electric wire, has a compact structure, and is easy to form, as well as an electric wire with a terminal and an electric wire with a connector that include the same. [Brief explanation of the drawings]

[0014] [Figure 1] FIG. 1 is a vertical cross-sectional view showing an example of an end structure of a shielded electric wire according to an embodiment. [Figure 2] FIG. 2 is a vertical cross-sectional view showing an example of a shielded electric wire used in the terminal structure of the shielded electric wire according to the embodiment. [Figure 3] FIG. 3 is an enlarged perspective view showing an example of a ferrule used in the terminal structure of the shielded electric wire according to the embodiment. [Figure 4] FIG. 4 is a vertical cross-sectional view showing the state of the tip of the shielded electric wire after the stripping process. [Figure 5] FIG. 5 is a vertical cross-sectional view showing the state of the tip end of the shielded electric wire after the sleeve fitting step has been performed. [Figure 6] FIG. 6 is a vertical cross-sectional view showing the state of the tip end of the shielded electric wire after the ferrule arrangement step has been performed. [Figure 7] FIG. 7 is a vertical cross-sectional view showing the state of the tip end of the shielded electric wire after the sleeve arrangement step has been performed. [Figure 8] FIG. 8 is a schematic diagram showing a connector-attached electric wire in which a terminal-attached electric wire having the terminal structure of the shielded electric wire according to the embodiment is accommodated in a connector housing. [Figure 9] FIG. 9 is an explanatory diagram showing a process for forming a conventional terminal structure of a shielded electric wire. DETAILED DESCRIPTION OF THE INVENTION

[0015] Hereinafter, a detailed description will be given based on an embodiment.

[0016] As a result of extensive research into the terminal structure of a shielded electric wire, the inventors have discovered that a ferrule having a corrugated tubular portion, with the ferrule tubular portion and the sleeve body portion sandwiching the exposed portion of the shielding layer without folding it back, with the holder body holding the ferrule tubular portion pressed and fixed against the sleeve body portion via the exposed portion of the shielding layer, and the holder abutment portion holding the end side of the ferrule tubular portion abutting against the exposed end of the outer jacket via the exposed portion of the shielding layer, results in a ferrule with high tensile strength against the shielded electric wire, a compact structure, and easy formation, and have completed the present disclosure based on this finding.

[0017] The terminal structure of the shielded electric wire of the embodiment is a terminal structure of the shielded electric wire having a core portion in which a conductor is covered with an insulating layer, a shielding layer arranged on the outer periphery of the core portion, and an outer sheath covering the outer periphery of the shielding layer. The terminal structure of the shielded electric wire includes a tubular portion having an inner diameter larger than the outer diameter of the core portion and extending in a wave shape, the tubular portion having an exposed portion of the shielding layer exposed when a predetermined length of the outer covering is peeled off, and a ferrule located between the tubular portion and the core portion; a sleeve body portion having an inner diameter larger than the outer diameter of the shielded electric wire, the sleeve body being fixed and disposed opposite the outer peripheral surface of the tubular portion with the exposed portion of the shielding layer sandwiched between the tubular portion and the sleeve body; a holder body portion having an outer diameter smaller than the inner diameter of the tubular portion, and a holder abutment portion extending radially outward from the end of the holder body on the base side of the tubular portion, the holder body portion being located between the inner peripheral surface of the tubular portion and a part of the outer peripheral surface of the core portion located on the inner peripheral surface side of the exposed portion of the shielding layer, and maintaining a state in which the tubular portion is pressed and fixed against the sleeve body portion via the exposed portion of the shielding layer, and the holder abutment portion being located closer to the tip of the shielded electric wire than the tubular portion and maintaining a state in which the end side of the tubular portion abuts against the exposed end of the outer covering via the exposed portion of the shielding layer.

[0018] Fig. 1 is a longitudinal sectional view showing an example of a terminal structure of a shielded electric wire according to an embodiment. Fig. 2 is a longitudinal sectional view showing an example of a shielded electric wire used in the terminal structure of a shielded electric wire according to an embodiment. Fig. 3 is an enlarged perspective view showing an example of a ferrule used in the terminal structure of a shielded electric wire according to an embodiment. As shown in Fig. 1, the terminal structure 1 of a shielded electric wire according to an embodiment (hereinafter also simply referred to as the terminal structure) includes a shielded electric wire 10, a ferrule 20, a sleeve 30, and a holder 50.

[0019] As shown in Fig. 2, the shielded wire 10 used in the terminal structure 1 has a core 11, a shield layer 14 arranged on the outer periphery of the core 11, and an outer sheath 15 that covers the outer periphery of the shield layer 14. The core 11 has a conductor 12 and an insulating layer 13, and the outer periphery of the conductor 12 is covered with the insulating layer 13. The shield layer 14 covers the outer periphery of the core 11. The outer sheath 15 is arranged on the outer periphery of the shield layer 14.

[0020] The conductor 12 of the shielded wire 10 is electrically conductive and made of a metal or alloy such as copper or a copper alloy, aluminum or an aluminum alloy, iron or an iron alloy such as stainless steel, or silver or a silver alloy. The insulating layer 13 and the outer jacket 15 are electrically insulating and made of an electrically insulating resin such as polyvinyl chloride or polyethylene.

[0021] The shield layer 14 is an electrically conductive layer made of a metal or alloy, such as copper or a copper alloy, aluminum or an aluminum alloy, iron or an iron alloy such as stainless steel, or silver or a silver alloy. Examples of the shield layer 14 include a braided wire made of these metal or alloy wires, a foil-wound wire made of unbraided metal or alloy foil wound in a spiral shape, or a layer made of a conductive polymer. The shield layer 14 may have any of these structures. It may also have a structure combining two or more of these layers (for example, a laminate of a braided wire layer and a foil-wound wire layer). The shield layer 14 is easily deformed by expansion and contraction.

[0022] In the terminal structure 1, as shown in FIG. 1 and FIG. 4 described later, the shielded wire 10 is stripped in a stepped manner from the tip 10e of the shielded wire 10 toward the base end (not shown) of the shielded wire 10 so that the outer periphery of the conductor 12, the outer periphery of the insulating layer 13, the outer periphery of the shielding layer 14, and the outer periphery of the outer jacket 15 each become the outermost periphery of the shielded wire 10.

[0023] 1 and 3, the ferrule 20 has an inner diameter larger than the outer diameter of the core portion 11 of the shielded electric wire 10 and includes a tubular portion 22 that extends in a corrugated shape. The ferrule 20 is a component that terminates an electric wire. The corrugated shape of the tubular portion 22 may extend along the circumferential direction of the tubular portion 22, but from the viewpoint of contracting the tubular portion 22 in the axial direction of the tubular portion 22 as described below, it is preferable that the corrugated shape extend along the axial direction of the tubular portion 22 as shown in FIGS.

[0024] As shown in Fig. 1, in the terminal structure 1, the tubular portion 22 is arranged so as to be located between the core portion 11 and an exposed portion of the shielding layer 14 that is exposed when a predetermined length of the outer jacket 15 is peeled off. The outer peripheral surface of the tubular portion 22 contacts the inner peripheral surface of the exposed portion of the shielding layer 14, and the inner peripheral surface of the tubular portion 22 contacts the outer peripheral surface of the holder body portion 51. The shielding layer 14 (exposed portion of the shielding layer 14) is not arranged on the inner peripheral side of the tubular portion 22. For example, as shown in Fig. 1, the thickness of the tubular portion 22 is approximately the same as the thickness of the shielding layer 14.

[0025] The ferrule 20 also includes a connecting portion 21 that is connected to a connected portion (not shown) of an external electronic device. The connecting portion 21 and the cylindrical portion 22 may be connected via a connecting portion 23 as shown in Figures 1 and 3, or may be connected directly.

[0026] The connecting portion 21 of the ferrule 20 is connected to a connected portion (not shown) of an external electronic device. The external electronic device is an electronic device separate from the shielded electric wire 10 and the terminal structure 1 of the embodiment, and examples thereof include various ECUs (Electronic Control Units), control devices, various motors, monitors, meters, various lamps, various sensors, and various other electrical components installed in automobiles. The connected portion of the external electronic device may be, but is not limited to, a connector 60 (described later), and may be anything electrically connected to the external electronic device. For example, the connected portion may be directly provided on the external electronic device, or may be connected to the external electronic device via a cable or the like. In particular, when the connected portion of the external electronic device is a connector 60 as shown in FIG. 8 , the shape of the connecting portion 21 of the ferrule 20 preferably corresponds to the shape of the connector 60.

[0027] Furthermore, although the connecting portion 21 of the ferrule 20 has a shape with a rectangular opening in FIG. 3, this is not limited to this, and the shape of the opening may be, for example, circular, elliptical, other polygonal, or irregular, as long as it is a shape that can be connected to the connecting portion of the external electronic device.

[0028] The ferrule 20 is electrically conductive and made of a metal or alloy, such as copper or a copper alloy, aluminum or an aluminum alloy, iron or an iron alloy such as stainless steel, etc. The ferrule 20 also has a hardness that allows it to maintain a predetermined shape.

[0029] The ring-shaped sleeve 30 has a sleeve body portion 31. The sleeve body portion 31 is ring-shaped and has an inner diameter larger than the outer diameter of the shielded wire 10. The thickness of the sleeve body portion 31 is larger than the thickness of the tubular portion 22 of the ferrule 20. As shown in FIG. 1 , the sleeve body portion 31 of the sleeve 30 is fixedly disposed in a position facing the outer peripheral surface of the tubular portion 22 of the ferrule 20, with the exposed portion of the shielding layer 14 sandwiched between the tubular portion 22 of the ferrule 20. The inner peripheral surface of the sleeve body portion 31 is in contact with the outer peripheral surface of the exposed portion of the shielding layer 14. The sleeve body portion 31 may also be formed by wrapping a band-shaped (strip-shaped) material around it to form a ring. The thickness of the sleeve body portion 31 is not particularly limited as long as it is larger than the thickness of the tubular portion 22, and is set appropriately depending on the application of the terminal structure 1, etc.

[0030] In the terminal structure 1, the state in which the exposed portion of the shielding layer 14 is sandwiched between the sleeve body 31 and the tubular portion 22 of the ferrule 20 means that the exposed portion of the shielding layer 14 is not folded back, and the exposed portion extending from the base end (not shown) of the shielded electric wire 10 to the tip end 10e is sandwiched between the sleeve body 31 and the tubular portion 22 of the ferrule 20.

[0031] The holder 50 includes a ring-shaped holder body 51 and a holder abutment portion 52. The holder body 51 has an outer diameter smaller than the inner diameter of the cylindrical portion 22 of the ferrule 20 and an inner diameter larger than the outer diameter of the insulating layer 13. The holder abutment portion 52 extends from the entire circumference of the end of the holder body 51 on the cylindrical portion base side toward the radially outer side of the holder body 51. The cylindrical portion base side is the side of the cylindrical portion 22 on which the connecting portion 23 (base) is located.

[0032] Regarding the holder 50, the holder body 51 is located between the outer surface portion of the insulating layer 13 of the core portion 11 located on the inner surface side of the exposed portion of the shielding layer 14 and the inner surface of the tubular portion 22 of the ferrule 20, and maintains a state in which the tubular portion 22 of the ferrule 20 is pressed and fixed against the inner surface of the sleeve body 31 via the exposed portion of the shielding layer 14, while the holder abutment portion 52 is located closer to the tip 10e of the shielded wire 10 than the tubular portion 22 of the ferrule 20, and maintains a state in which the portion on the end 22e side of the tubular portion 22 abuts against the exposed end 15a of the outer jacket 15 via the exposed portion of the shielding layer 14.

[0033] The inner peripheral surface of the holder body portion 51 faces the outer surface of the insulating layer 13. As shown in FIG. 1 , the entire inner surface of the holder body portion 51 may be in contact with the outer surface of the insulating layer 13, or a portion of the inner surface of the holder body portion 51 may be in contact with the outer surface of the insulating layer 13, or the inner surface of the holder body portion 51 may not be in contact with the outer surface of the insulating layer 13. In addition, the outer peripheral surface of the holder body portion 51 presses against the inner peripheral surface of the tubular portion 22 of the ferrule 20. The shield layer 14 (the exposed portion of the shield layer 14) is not arranged on the inner peripheral side of the holder body portion 51.

[0034] Here, when forming the terminal structure 1 described later, when the holder 50 is inserted into the ferrule 20 in which the tubular portion 22 is arranged between the outside of the insulating layer 13 and the inside of the exposed portion of the shielding layer 14, so that the holder body 51 is arranged between the outer surface portion of the insulating layer 13 and the inner surface of the tubular portion 22, the holder body 51 presses the tubular portion 22 radially outward from the tubular portion 22, and further the holder abutment portion 52 presses the tubular portion 22 toward the end 22e side.

[0035] When the corrugated tubular portion 22 is pressed radially outward by the holder body portion 51, the tubular portion 22 abuts against the inner surface of the sleeve body portion 31 via the exposed portion of the shielding layer 14 and is gradually pressed against the sleeve body portion 31 via the exposed portion of the shielding layer 14, and in some cases, the tubular portion 22 is deformed so that the height of the corrugations becomes smaller. The fact that the tubular portion 22 of the ferrule 20 is pressed against the sleeve body portion 31 via the exposed portion of the shielding layer 14 is maintained by the holder body portion 51 being provided between the insulating layer 13 and the tubular portion 22. Furthermore, when the corrugated tubular portion 22 is pressed toward the end portion 22e by the holder abutment portion 52, the end portion 22e of the tubular portion 22 is pressed against the exposed end portion 15a of the jacket 15 via the exposed portion of the shielding layer 14, and the tubular portion 22 contracts in the axial direction from the end portion 22e side so that the corrugations gradually become smaller. The pressure of the cylindrical portion 22 against the exposed end portion 15 a is maintained by the holder body portion 51 pressing the cylindrical portion 22 against the sleeve body portion 31 .

[0036] In this way, the holder body portion 51 holds the corrugated tubular portion 22 in a state in which it is pressed and fixed against the inner circumferential surface of the sleeve body portion 31 via the exposed portion of the shielding layer 14. Furthermore, the holder abutting portion 52 holds the end side of the tubular portion 22 in a state in which it is pressed against the exposed end portion 15a of the outer jacket 15 via the exposed portion of the shielding layer 14. Due to the pressing force in the radial expansion direction from the holder body portion 51, the tubular portion 22 is pressed against the inner circumferential surface of the exposed portion of the shielding layer 14, and the outer circumferential surface of the exposed portion of the shielding layer 14 is pressed against the inner circumferential surface of the sleeve body portion 31. Furthermore, due to the axial pressing force from the holder abutting portion 52, the end side of the tubular portion 22 is fixed to the exposed end portion 15a of the outer jacket 15 via the exposed portion of the shielding layer 14. In this way, the exposed portion of the shielding layer 14 is sandwiched and fixed between the outer peripheral surface of the tubular portion 22 and the inner peripheral surface of the sleeve body portion 31, and the exposed portion of the shielding layer 14 is fixed between the end side of the tubular portion 22 and the exposed end portion 15a of the jacket 15. This improves the tensile strength of the ferrule 20 relative to the shielded wire 10.

[0037] Furthermore, in the terminal structure 1, the cylindrical portion 22 of the ferrule 20 and the sleeve body portion 31 of the sleeve 30 are each crimped and fixed to the shielded wire 10 with the corrugated cylindrical portion 22 from the inside and the sleeve body portion 31 from the outside sandwiching the exposed portion of the shielding layer 14 without folding it back. Furthermore, the shielding layer 14 is not provided inside the cylindrical portion 22 of the ferrule 20. In this way, the corrugated cylindrical portion 22 and the sleeve body portion 31 are crimped together with the shielding layer 14 sandwiched between them without folding back the exposed portion, and the shielding layer 14 is not disposed inside the cylindrical portion 22. This allows the tensile strength of the ferrule 20 relative to the shielded wire 10 to be increased.

[0038] In addition, in the termination structure 1, the tubular portion 22 of the ferrule 20, which sandwiches the exposed portion of the shielding layer 14 from the inside without folding it back, is provided on the holder body portion 51 that is placed on the exposed portion of the insulating layer 13 after the shielding layer 14 and the outer jacket 15 have been removed. In addition, the sleeve body portion 31 of the sleeve 30, which sandwiches the exposed portion of the shielding layer 14 from the outside without folding it back, is provided on the exposed portion of the shielding layer 14 after the outer jacket 15 has been removed. In this way, the shielding layer 14 is crimped to the tubular portion 22 of the ferrule 20 and the sleeve 30 without folding back the exposed portion, and the tubular portion 22 and sleeve body portion 31 that sandwich the exposed portion of the shielding layer 14 are not provided on the outer periphery of the outer jacket 15 of the shielded electric wire 10. This allows the termination structure 1 to be made compact.

[0039] Furthermore, the shielded wire 10 is stripped in a stepped pattern so that the outer circumferential surfaces of the conductor 12, insulating layer 13, shielding layer 14, and jacket 15 all become outermost from the tip 10e of the shielded wire 10 toward the base end (not shown) of the shielded wire 10. The ferrule 20 and sleeve 30 are fixed to the shielding layer 14 without folding back the shielding layer 14. This allows the termination structure 1 to be easily formed.

[0040] Furthermore, as shown in FIG. 1, in the terminal structure 1, the sleeve 30 further includes a sleeve abutment portion 32 extending radially inward from the end of the sleeve body 31 on the tubular portion end side, and it is preferable that the holder abutment portion 52 maintains the end side of the tubular portion 22 in a state of abutting against the exposed end portion 15a of the outer jacket 15 and the sleeve abutment portion 32 via the exposed portion of the shielding layer 14.

[0041] The sleeve abutment portion 32 extends from the entire circumference of the end portion of the sleeve body portion 31 on the tubular portion end side toward the radially inner side of the sleeve body portion 31. The tubular portion end side is the side opposite to the tubular portion base side. In order to maintain a state in which the end side of the tubular portion 22 abuts against the sleeve abutment portion 32 via the exposed portion of the shielding layer 14, it is preferable that the radially inner end face of the sleeve abutment portion 32 (end face of the sleeve abutment portion) abuts against the outer peripheral surface of the jacket 15 as shown in FIG. 1 .

[0042] In this way, the holder abutment portion 52 keeps the end 22e side of the tubular portion 22 in abutment with the exposed end 15a of the outer jacket 15 and the sleeve abutment portion 32 of the sleeve 30 via the exposed portion of the shielding layer 14, thereby further increasing the tensile strength of the ferrule 20 relative to the shielded wire 10.

[0043] Next, a method for forming the terminal structure of the embodiment will be described. The method for forming the terminal structure 1 includes a stripping step, a sleeve fitting step, a ferrule arrangement step, a sleeve arrangement step, and a crimping step.

[0044] The stripping step is a step of stripping the tip of the shielded electric wire 10 shown in Fig. 2. Fig. 4 is a vertical cross-sectional view showing the state of the tip of the shielded electric wire 10 after the stripping step has been performed.

[0045] In the stripping process, as shown in FIG. 4, stripping is performed so that the outer surface 12s of the conductor 12, the outer surface 13s of the insulating layer 13, the outer surface 14s of the shielding layer 14, and the outer surface 15s of the jacket 15 appear in a stepped pattern from the tip 10e of the shielded wire 10 toward the base end (not shown) of the shielded wire 10. Stripping can be completed in a single operation of stripping the jacket 15, shielding layer 14, and insulating layer 13 toward the tip 10e of the shielded wire 10. This improves the work efficiency when forming the termination structure 1. The stripping can be performed using conventionally known devices and tools, such as a measuring stripping device.

[0046] In the sleeve fitting process carried out after the stripping process, a sleeve 30 is fitted onto the tip 10e of the shielded electric wire 10 and left standing at the outer peripheral surface 15s of the jacket 15. Fig. 5 is a vertical cross-sectional view showing the state of the tip end of the shielded electric wire 10 after the sleeve fitting process has been carried out.

[0047] 5, in the sleeve fitting step, the sleeve 30 is arranged so as to be retracted to the position of the outer peripheral surface 15s of the jacket 15 of the shielded electric wire 10. In this embodiment, a metal molded product formed into a ring shape is used as the sleeve 30.

[0048] After the sleeve 30 is fitted onto the shielded electric wire 10, the shield layer 14 constituting the shielded electric wire 10 is expanded (expanded in diameter) into a horn shape (reference symbol 14f), and a gap 14g is provided between the shield layer 14 and the insulating layer 13. As will be described later, the cylindrical portion 22 of the ferrule 20 and the holder body portion 51 of the holder 50 are fitted into this gap 14g. Here, one method for expanding the shield layer 14 of the shielded electric wire 10 to form the gap 14g is to loosen the braid of the shield layer 14 and bend it outward to expand it into a horn shape. Figure 5 shows the shield layer 14 in the horn shape (reference symbol 14f).

[0049] The ferrule arrangement process, which is performed after the sleeve fitting process, is a process of fitting the cylindrical portion 22 of the ferrule 20 from the side of the tip portion 14e of the shield layer 14 into the gap 14g between the shield layer 14 and the core portion 11, more strictly speaking, between the shield layer 14 and the insulating layer 13. In the sleeve fitting process, the shield layer 14 is expanded to provide the gap 14g, so that the cylindrical portion 22 of the ferrule 20 can be smoothly fitted into the gap 14g.

[0050] Fig. 6 is a vertical cross-sectional view showing the state of the tip end of the shielded wire 10 after the ferrule arrangement step has been performed. Fig. 6 shows the state in which the trumpet-shaped portion 14f of the shielding layer 14 is further expanded (jumped up) when the cylindrical portion 22 of the ferrule 20 is fitted into the small gap 14g between the shielding layer 14 and the insulating layer 13.

[0051] The sleeve placement process, which is performed after the ferrule placement process, is a process in which the sleeve 30 is moved to the area where the tubular portion 22 of the ferrule 20 is located and placed in a position facing the outer circumferential surface of the tubular portion 22, sandwiching the exposed portion of the shielding layer 14. In the sleeve placement process, the sleeve 30 moves in the direction indicated by arrow X in FIG.

[0052] 7 is a vertical cross-sectional view showing the state of the tip end of the shielded wire 10 after the sleeve placement step has been performed. In the sleeve placement step, the trumpet-shaped portion 14f of the expanded (flung up) shield layer 14 is pressed down and placed over the outer circumferential surface of the tubular portion 22 when the sleeve 30 is moved to a position facing the outer circumferential surface of the tubular portion 22. In other words, the exposed portion of the shield layer 14 is sandwiched between the tubular portion 22 of the ferrule 20 and the sleeve body portion 31.

[0053] The crimping process, which is performed after the sleeve arrangement process, is a process in which the tubular portion 22 is deformed and expanded outward to crimp the tubular portion 22 and the sleeve body portion 31 onto the exposed portion of the shielding layer 14, and the tubular portion 22 is pressed in the axial direction to crimp the end side of the tubular portion 22 and the sleeve abutting portion 32 onto the exposed portion of the shielding layer 14. As a result, with the exposed portion of the shielding layer 14 sandwiched between them, the tubular portion 22 and the sleeve 30 are crimped and fixed, and the tubular portion 22 and the sleeve abutting portion 32 are also crimped and fixed, thereby fixing the ferrule 20 and the sleeve 30 to the shielded electric wire 10.

[0054] In the crimping process, the holder body portion 51 is fitted into the gap 14g between the tubular portion 22 and the insulating layer 13 from the side of the tip 10e of the shielded wire 10 along the direction indicated by arrow Y in FIG. 7 until the holder abutting portion 52 abuts the connecting portion 23. As a result, the tubular portion 22 is expanded in diameter and deformed and is pressed against the exposed end portion 15a of the outer jacket 15 and the sleeve abutting portion 32, so that the tubular portion 22, the sleeve body portion 31, and the sleeve abutting portion 32 are crimped and fixed to the exposed portion of the shielding layer 14. In addition, the tip side of the tubular portion 22 is pressed and fixed to the exposed end portion 15a of the outer jacket 15. In this way, the exposed portion of the shielding layer 14 sandwiched between the tubular portion 22 and the sleeve 30 can be crimped and fixed to the tubular portion 22 and the sleeve 30.

[0055] In this way, it is possible to form the shielded electric wire terminal structure 1 shown in Fig. 1. According to this method for forming the terminal structure 1, it is possible to complete the stripping process of the tip portion of the shielded electric wire 10 in one go so that the conductor 12, the insulating layer 13, the shielding layer 14, and the outer jacket 15 each form the outermost periphery, and it is also possible to eliminate the need for folding back the shielding layer 14, so that the shielded electric wire terminal structure 1 with excellent properties can be easily formed with a reduced amount of work.

[0056] Next, an electric wire with terminal of an embodiment will be described. The electric wire with terminal of the embodiment has a terminal structure 1 of a shielded electric wire, in which a predetermined length of insulating layer is peeled from the tip of the core part, and the part of the conductor exposed by the peeling is connected to a terminal.

[0057] Fig. 8 is a schematic diagram showing a connector-attached electric wire in which an electric wire with a terminal having the terminal structure of the shielded electric wire of the embodiment is accommodated in a connector housing. As shown in Fig. 8, the electric wire with terminal 4 has the terminal structure 1 of the shielded electric wire of the above embodiment, and a terminal 40 is connected to the end of the conductor wire 12, and the conductor wire 12 and the terminal 40 can be connected by, for example, ultrasonic welding. Here, the electric wire with terminal 4 is formed by peeling a predetermined length of the insulating layer 13 from the tip of the core portion 11 of the shielded electric wire 10, and connecting the portion of the conductor wire 12 exposed by the peeling to the terminal 40, thereby electrically connecting the terminal 40 and the conductor wire 12.

[0058] In the shielded electric wire termination structure 1, a predetermined length of the insulating layer 13 is peeled off from the tip of the core portion 11 of the shielded electric wire 10, so that the exposed conductor 12 in the shielded electric wire termination structure 1 can be connected to a terminal 40 to form an electric wire with terminal 4. This terminal 40 may be electrically connected to a connection terminal (not shown) provided on a connected portion of an external electronic device.

[0059] The electric wire with terminal 4 is formed by connecting the terminal 40 to the end of the conductor 12 in the shielded electric wire termination structure 1. The connection between the conductor 12 and the terminal 40 may be by welding, or by other connection methods such as soldering, crimping, or locking.

[0060] Next, a description will be given of an electric wire with a connector according to an embodiment. In the electric wire with a connector according to the embodiment, an electric wire with a terminal 4 is accommodated in a connector housing, and a metal member is disposed in the connector housing over an area facing the terminal and the ferrule, and the ferrule and the metal member are electrically connected.

[0061] As shown in Fig. 8, in the connector-attached electric wire 6, the terminal-attached electric wire 4 is accommodated in a connector 60, more specifically, a connector housing 60a. In this connector-attached electric wire 6, a metal member 61 is disposed in the connector housing 60a over an area facing the terminal 40 and the ferrule 20, and the ferrule 20 and the metal member 61 are configured to be electrically conductive. Here, the shape of the metal member 61 is not particularly limited as long as it has a shape that roughly corresponds to the outer shape of the ferrule 20. Note that Fig. 8 shows a case where the shape of the metal member 61 is formed into a rectangular tube shape.

[0062] The terminal 40 constituting the terminal-fitted wire 4 is disposed at the tip side of the connector 60, and by inserting another terminal to be connected, the terminals can be electrically connected to each other. Meanwhile, inside the connector 60, the ferrule 20 comes into contact with a metal member 61 for electrical continuity. The metal member 61 is connected to a ground wire (not shown), so the shield layer 14 constituting the shielded wire 10 can be grounded.

[0063] The connector-attached electric wire 6 is formed by attaching the terminal-attached electric wire 4 to a connector 60, more specifically, a connector housing 60a, to form the connector-attached electric wire 6. The connector 60 is formed by arranging a metal member 61 in the connector housing 60a over an area facing the terminal 40 and the ferrule 20, and the terminal 40 of the terminal-attached electric wire 4 is inserted into the terminal insertion portion of the connector housing 60a, and the shield layer 14 and the connection portion 21 of the ferrule 20 are brought into contact with each other. This prevents contact between the terminal 40 inserted into the terminal insertion portion and the metal member 61, and also enables electrical conduction between the ferrule 20 and the metal member 61 arranged on the inner surface of the terminal insertion portion of the connector housing.

[0064] According to the embodiment described above, the ferrule has a corrugated tubular portion, and with the ferrule tubular portion and the sleeve body portion sandwiching the exposed portion of the shielding layer without folding it back, the holder body holds the ferrule tubular portion pressed and fixed to the sleeve body portion via the exposed portion of the shielding layer, and the holder abutment portion holds the end side of the ferrule tubular portion in abutment against the exposed end of the outer jacket via the exposed portion of the shielding layer, so that the terminal structure of the shielded electric wire has a high tensile strength of the ferrule against the shielded electric wire, a compact structure, and can be easily formed.

[0065] The above-described embodiments merely show typical examples of the present invention, and the present invention is not limited to the above-described embodiments. For example, in the above-described embodiments, the shielded electric wire 10 is described as a shielded electric wire of a so-called coaxial cable, in which the core portion 11 is made of one conductor wire 12 covered with one insulating layer 13. However, in the present invention, the core portion may be a bundle of two or more electric wires (i.e., conductor wires covered with an insulating layer). Furthermore, in the above-described embodiments, the conductor wire 12 is described as a single wire, but the conductor wire 12 of the present invention may be a twisted wire in which two or more wires are twisted together.

[0066] Furthermore, although the above example shows the case where the holder 50 is installed as shown in Figure 1, as long as the deformed state of the tubular portion 22 can be maintained in the same manner as when the holder 50 is installed, the configuration may be such that the corrugated tubular portion 22 is deformed using a deformation jig or the like, the deformed state of the deformed tubular portion 22 is maintained, and the holder 50 is not installed.

[0067] In addition, those skilled in the art can implement various modifications in accordance with conventionally known knowledge without departing from the gist of the present invention. As long as such modifications still provide the configuration of the shielded electric wire terminal structure, electric wire with terminal, and electric wire with connector of the present invention, they are of course included in the scope of the present invention. [Explanation of symbols]

[0068] 1: Terminal structure of shielded wire (Terminal structure) 4: Wire with terminal 6: Wire with connector 10: Shielded wire 11: Core section 12: Conductor 13: Insulating layer 14: Shield layer 15:Outer cover 15a:Exposed end 20: Ferrule 21: Connection 22: Cylindrical part 22e: End 23:Connection part 30: Sleeve 31: Sleeve body 32: Sleeve contact part 40: Terminal 50: Holder 51: Holder body 52: Holder contact part 60: Connector 60a: Connector housing 61: Metal parts 100: Shielded wire 103:Outer cover 105: Shield layer 107: Core section 109: Inner ferrule 113: Outer ferrule

Claims

1. A terminal structure of a shielded electric wire having a core portion in which a conductor is covered with an insulating layer, a shield layer disposed on the outer periphery of the core portion, and an outer sheath covering the outer periphery of the shield layer, a ferrule having an inner diameter larger than the outer diameter of the core portion and including a cylindrical portion extending in a wave shape, the cylindrical portion being positioned between the core portion and an exposed portion of the shielding layer exposed when a predetermined length of the outer jacket is stripped off; a ring-shaped sleeve including a sleeve body portion having an inner diameter larger than an outer diameter of the shielded electric wire, the sleeve body portion being fixed and disposed at a position facing an outer peripheral surface of the cylindrical portion in a state in which the exposed portion of the shielding layer is sandwiched between the sleeve body portion and the cylindrical portion; a holder including a holder body having an outer diameter smaller than the inner diameter of the cylindrical portion, and a holder abutment portion extending radially outward from an end of the holder body on the cylindrical portion base side, the holder body being located between an inner peripheral surface of the cylindrical portion and a portion of an outer peripheral surface of the core portion located on the inner peripheral surface side of the exposed portion of the shielding layer, and maintaining a state in which the cylindrical portion is pressed and fixed to the sleeve body via the exposed portion of the shielding layer, and the holder abutment portion being located closer to the tip of the shielded electric wire than the cylindrical portion, and maintaining a state in which the end side of the cylindrical portion abuts against the exposed end of the outer jacket via the exposed portion of the shielding layer; A terminal structure of a shielded electric wire comprising:

2. the sleeve further includes a sleeve abutment portion extending radially inward from an end of the sleeve body portion on a cylindrical portion end side thereof, 2. The shielded wire terminal structure according to claim 1, wherein the holder abutment portion maintains the end side of the tubular portion in abutment with the exposed end of the outer jacket and the sleeve abutment portion via the exposed portion of the shielding layer.

3. A terminal-attached electric wire having the terminal structure of the shielded electric wire according to claim 1 or 2, The electric wire with terminal, wherein a predetermined length of the insulating layer is peeled off from the tip of the core portion, and the portion of the conductor exposed by the peeling is connected to a terminal.

4. A connector-attached electric wire in which the terminal-attached electric wire according to claim 3 is accommodated in a connector housing, a metal member is disposed in the connector housing over an area facing the terminal and the ferrule; The ferrule and the metal member are electrically connected to each other.

Images