Covered electrical wire, terminal-equipped electrical wire, and method for manufacturing terminal-equipped electrical wire

Abstract

To provide a coated electric wire, an electric wire with a terminal, and a method of manufacturing the electric wire with the terminal, having versatility for easily sharing a wire seal.SOLUTION: The coated wire 10 includes a core 11 and a coating 12 for circumferentially covering the core 11. The covering portion 12 is provided with a mounting portion 14 for supporting the tubular rubber plug 20 by being inserted into the rubber plug 20. The mounting portion 14 is formed integrally with the coating portion 12 by resin molding, and is formed in a different-diameter tubular shape having an outer diameter different from that of a portion of the coating portion 12 other than the mounting portion 14.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a coated electric wire, an electric wire with a terminal, and a method for manufacturing an electric wire with a terminal. [Background technology]

[0002] Conventionally, electric wires with terminals used in wire-seal type waterproof connectors have been known (see, for example, Patent Document 1). The electric wire with terminal described in Patent Document 1 includes a covered electric wire composed of an exposed core wire and a covering portion, a crimp terminal connected to an end portion of the covered electric wire, and a rubber stopper as a wire seal interposed between the crimp terminal and the covered electric wire. The rubber stopper is formed in a tubular shape that circumferentially surrounds the covered electric wire. The crimp terminal includes a covering crimping portion that circumferentially surrounds and crimps the rubber stopper. By crimping the covering crimping portion, the crimp terminal and the rubber stopper are integrated, and the rubber stopper is pressed against the covering portion of the covered electric wire, thereby integrating the crimp terminal, the rubber stopper, and the covered electric wire. For example, a plurality of electric wires with terminals are housed together in a housing to be connected, forming a waterproof connector, which is connected to various devices such as home appliances, automobiles, and machine tools. When the terminal-equipped wire is connected to the housing, the outer surface of the insulated wire is closely attached to the inner surface of the rubber stopper, and the outer surface of the rubber stopper is closely attached to the object to be connected, thereby improving waterproofing at the closely attached parts. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2023-9515 [Patent Document 2] Japanese Patent Application Publication No. 07-335282 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-168257 Summary of the Invention [Problem to be solved by the invention]

[0004] In the electric wire with terminal described in Patent Document 1, the adhesion between the rubber stopper and the insulated electric wire is determined by the balance between the inner diameter of the rubber stopper and the outer diameter of the insulated electric wire. However, the insulated electric wires with terminals used in waterproof connectors generally are not limited to a single type. For example, an electric wire with terminals may be manufactured using multiple insulated electric wires with different outer diameters, and each of the insulated electric wires may be connected to a connection target. In this case, multiple rubber stoppers with different inner diameters corresponding to the respective insulated electric wires must be molded. Furthermore, an insertion machine for inserting these rubber stoppers into the insulated electric wires must be prepared for each rubber stopper. This makes it difficult to manufacture waterproof connectors. To address this issue, it is conceivable to standardize the rubber stoppers by making the outer diameter of a portion of the insulated electric wire a predetermined size, thereby aligning the outer diameter at the installation position of the rubber stopper (see, for example, Patent Documents 2 and 3).

[0005] In the crimp terminal connection structure described in Patent Document 2, the outer diameter of the end of the insulating coating of the electric wire is reduced by stripping the end of the insulating coating into a stepped shape using a slitter. However, with this configuration, the stepped portion has an inconsistent outer diameter, which tends to reduce adhesion between the electric wire and the rubber plug, raising concerns about the aforementioned waterproofing. Alternatively, it is conceivable to use a slitter to cut and remove the insulating coating at a constant thickness to ensure a constant outer diameter at the rubber plug's installation location. However, for example, electric wires used in waterproof connectors can have small diameters, approximately 0.1 mm to 2 mm, making the above-mentioned cutting and other operations difficult. In contrast, the increased-diameter electric wire described in Patent Document 3 uses an increased-diameter member, which is a tubular member one size larger than the electric wire. The electric wire is inserted through the increased-diameter member, and the electric wire and the increased-diameter member are brought into close contact with each other, thereby increasing the outer diameter of a portion of the electric wire. However, this configuration requires a separate increased-diameter member, which increases the component costs of the waterproof connector. Furthermore, this configuration is not able to accommodate smaller electric wire diameters. Therefore, it is difficult to standardize the rubber plug (wire seal).

[0006] An object of the present invention is to provide a versatile coated electric wire, an electric wire with a terminal, and a method for manufacturing an electric wire with a terminal, which allows for easy standardization of wire seals. [Means for solving the problem]

[0007] In order to solve the above problems and achieve the object, the insulated electric wire is an insulated electric wire comprising a core wire portion and a covering portion that circumferentially covers the core wire portion, wherein the covering portion is provided with an attachment portion for inserting into a cylindrical wire seal to support the wire seal, and the attachment portion is formed integrally with the covering portion by resin molding and into a cylindrical shape with a different outer diameter that is different from the outer diameter of the portion of the covering portion other than the attachment portion. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide a coated electric wire, an electric wire with a terminal, and a method for manufacturing an electric wire with a terminal, which are versatile and allow wire seals to be easily standardized. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a partially simplified side view showing a waterproof connector provided with a coated electric wire according to a first embodiment. [Figure 2] 1A is a partially simplified side view of the insulated electric wire before the attachment portion is formed, FIG. 1B is a partially simplified side view of the insulated electric wire after the attachment portion is formed, and FIG. 1C is a partially simplified side view of the insulated electric wire with a wire seal attached to the attachment portion. [Figure 3] 10(A) to 10(C) are side views corresponding to FIGS. 2(A) to 2(C) in a modified example of the first embodiment. [Figure 4] 10(A) to 10(C) are side views corresponding to FIGS. 2(A) to 2(C) in the second embodiment. [Figure 5] 10A to 10D are side views showing displacement of a wire seal in a waterproof connector that does not have a first restricting portion and a second restricting portion. [Figure 6] 10(A) to 10(C) are side views corresponding to FIGS. 2(A) to 2(C) in a first modified example of the second embodiment. [Figure 7]10(A) to 10(C) are side views corresponding to FIGS. 2(A) to 2(C) in a second modified example of the second embodiment. [Figure 8] 10(A) to 10(C) are side views corresponding to FIGS. 2(A) to 2(C) in a third modified example of the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] A waterproof connector 100 including a covered electric wire 10 will be described below. FIG. 1 is a side view showing, in a partially simplified form, the waterproof connector 100 including the covered electric wire 10 of a first embodiment. FIG. 2(A) is a side view showing, in a partially simplified form, the covered electric wire 10 before the fitting portion is formed, FIG. 2(B) is a side view showing, in a partially simplified form, the covered electric wire 10 after the fitting portion is formed, and FIG. 2(C) is a side view showing, in a partially simplified form, the covered electric wire 10 with a rubber stopper 20 (wire seal) attached to the fitting portion. The waterproof connector 100 is a connector connected to various devices such as home appliances, automobiles, and machine tools. As shown in FIG. 1, the waterproof connector 100 includes a terminal-fitted electric wire 1 and a housing 2 (connection target) that accommodates the terminal-fitted electric wire 1. The terminal-fitted electric wire 1 includes the covered electric wire 10, the rubber stopper 20 (wire seal), and a crimp terminal 30 (terminal). In the drawings, the axial direction of the core 11 of the coated electric wire 10 is referred to as the "axial direction X." One side of the axial direction X is referred to as the "front side X1," and the other side of the axial direction X is referred to as the "rear side X2." Note that these definitions of directions are merely for the convenience of explanation and do not limit the directions when the waterproof connector 100 is actually used, etc.

[0011] As shown in FIG. 2A, the coated electric wire 10 includes a core portion 11 as a conductor. The core portion 11 is formed into a linear shape by processing a conductive metal such as copper, copper alloy, or aluminum, or by bundling multiple wires of an aluminum alloy or the like. The core portion 11 may also be a twisted core wire formed by twisting multiple wires together. A cylindrical coating portion 12 is formed on the outer circumferential surface of the core portion 11, covering the core portion 11 in the circumferential direction around the axis. The coating portion 12 is formed, for example, by extrusion molding a thermoplastic insulating resin material. The material of the coating portion 12 is selected appropriately from PP (polypropylene), PVC (polyvinyl chloride), cross-linked PE (polyethylene), etc., taking into consideration abrasion resistance, chemical resistance, heat resistance, etc. The front side X1 end of the coating portion 12 forms an installation position 13 (predetermined position) where the rubber stopper 20 is installed in this embodiment.

[0012] As shown in FIG. 2(B), an attachment portion 14 (terminal structure) is formed at the installation position 13 to be inserted into the rubber stopper 20 and support the rubber stopper 20. The attachment portion 14 includes a main body portion 15 formed in a cylindrical shape integral with the covering portion 12. The main body portion 15 includes an outer peripheral surface 15a (outer surface) that extends in the axial direction X and abuts against the inner peripheral surface of the rubber stopper 20. The outer diameter of the main body portion 15 is set to a predetermined dimension that allows the outer peripheral surface 15a to be in close contact with the inner surface of the rubber stopper 20. Specifically, in this embodiment, the predetermined dimension is smaller than the portion of the covering portion 12 where the attachment portion 14 is not provided, and is set to be approximately the same as or slightly larger than the inner diameter of the rubber stopper 20 before elastic deformation.

[0013] That is, the attachment portion 14 is formed by resin molding into a cylindrical shape that is integral with the covering portion 12 and has a different outer diameter from the other portions of the covering portion 12 (portions other than the attachment portion 14). The attachment portion 14 can be formed by resin molding using pellets made of the same material as the covering portion 12, or recycled material obtained by peeling (separating) a portion of the covering portion 12. Note that, when the outer diameter of the main body portion 15 (attachment portion 14) is smaller than the other portions of the covering portion 12, as in this embodiment, this covering portion 12 may be referred to as a large-diameter covering for convenience. In other words, a covering portion 12 in which the outer diameter of the portion continuing to the attachment portion 14 is larger than the outer diameter of the main body portion 15 (attachment portion 14) is referred to as a large-diameter covering.

[0014] As shown in FIG. 2(C), a rubber stopper 20 is attached (placed) on the attachment portion 14. The rubber stopper 20 is formed in a cylindrical shape extending in the axial direction X and covers the covering portion 12 in the circumferential direction around the axis. The rubber stopper 20 includes a large diameter portion 21 constituting the rear side X2 portion and a small diameter portion 22 constituting the front side X1 portion. The outer peripheral surface 21a of the large diameter portion 21 can be closely fitted to the inner peripheral surface of the housing 2. The close contact of the outer peripheral surface 21a of the large diameter portion 21 with the inner peripheral surface of the housing 2 seals the gap between the rubber stopper 20 and the housing 2. The small diameter portion 22 is formed in a cylindrical shape that is coaxial with the large diameter portion 21 and has a smaller diameter than the large diameter portion 21. The rubber stopper 20 formed in this manner is elastically deformable radially outward using a jig such as an insertion machine, and its inner diameter increases during elastic deformation. This makes it easier to insert the coated electric wire 10 into the rubber plug 20 in the elastically deformed state, and in this state, the rubber plug 20 can be easily moved in the axial direction X.

[0015] Then, the rubber stopper 20 is moved to the position of the attachment portion 14 and returned to its pre-elastic deformation state, whereby the inner diameter of the rubber stopper 20 returns to its pre-elastic deformation state, and the rubber stopper 20 is securely attached to the attachment portion 14. When the rubber stopper 20 is attached, the inner peripheral surface of the rubber stopper 20 is in close contact with the outer peripheral surface 15a of the main body 15, and this close contact seals the gap between the rubber stopper 20 and the coating portion 12. As shown in FIG. 1 , a crimp terminal 30 is connected to the insulated electric wire 10 and the rubber stopper 20. The crimp terminal 30 is formed by subjecting a conductive metal plate to processes such as punching and bending, and includes a flat bottom plate portion 31 extending in the axial direction X. A pair of plate-shaped coating crimping portions 32 (terminal rear legs) rising from both left and right edges are formed at the end of the rear side X2 of the bottom plate portion 31. The covering crimping portion 32 is crimped radially inward of the rubber stopper 20 with its inner surface positioned along the outer circumferential surface 22a of the small diameter portion 22 of the rubber stopper 20. By this crimping, the covering crimping portion 32 is directly fixed to the small diameter portion 22 and indirectly fixed to the covering portion 12.

[0016] A core wire crimping portion 33 (terminal front legs) composed of a pair of barrel pieces rising from both left and right edge portions of the bottom plate portion 31 is formed on the front side X1 of the coating crimping portion 32. The core wire crimping portion 33 is crimped radially inward of the core wire portion 11 with its inner surface positioned along the exposed portion of the core wire portion 11. This crimping allows the core wire crimping portion 33 to be directly fixed to the core wire portion 11. Fixing the core wire crimping portion 33 to the core wire portion 11 establishes electrical continuity between the coated electric wire 10 and the crimp terminal 30. An electrical connection portion 34 is formed on the front side X1 of the core wire crimping portion 33. The electrical connection portion 34 is a portion that is conductive with a mating terminal (not shown) to which the terminal-fitted electric wire 1 is connected within the housing 2, and is formed into a box shape extending in the axial direction X by bending plate members rising from both left and right edge portions of the bottom plate portion 31. The electric wire with terminal 1 thus formed is inserted into the housing 2 from the rear side X2 toward the front side X1, with the electrical connection portion 34 at the front. The housing 2 is formed into a box shape using, for example, a synthetic resin, and is configured to be able to accommodate a plurality of electric wires with terminal 1.

[0017] Here, the types of the insulated electric wires 10 constituting the electric wire with terminal 1 inserted into the housing 2 are not necessarily the same. For example, as described above, there is a case where an electric wire with terminal 1 constituted by an insulated electric wire 10 having a large outer diameter coating portion 12 (large diameter coating) and an electric wire with terminal 1 constituted by an insulated electric wire having a small outer diameter coating portion (small diameter coating, described later) are inserted into one housing 2. There is also a case where a plurality of electric wires with terminal 1 constituted by insulated electric wires 10 having coating portions 12 (large diameter coating) are inserted into one housing 2. And there is a case where a plurality of electric wires with terminal 1 constituted by insulated electric wires having a small outer diameter coating portion (small diameter coating, described later) are inserted into another housing 2. That is, there is a case where the type of the electric wire with terminal 1 to be connected to each of the plurality of housings 2 is changed. In such a case, if rubber stoppers 20 are prepared according to the outer diameter of each coating portion 12 without providing the attachment portion 14 of this embodiment, rubber stoppers 20 with different inner diameters are required at least for the number of patterns of the outer diameter of the coating portions 12. This increases the number of parts in the waterproof connector 100, and increases the cost of the parts.

[0018] Furthermore, the outer diameter of the rubber stoppers 20 often remains the same regardless of the type, making it difficult to distinguish the type of rubber stopper 20 from its appearance. In this case, it is necessary to color-code the rubber stoppers 20 according to their type to prevent incorrect installation of the insulated electric wire 10, which is cumbersome. Furthermore, color-coding the rubber stoppers 20 does not completely prevent such incorrect installation. In such cases, the seal between the insulated electric wire 10 and the rubber stopper 20 may be insufficient, resulting in a reduced or lost waterproofing. Furthermore, if multiple rubber stoppers 20 are prepared, the above-mentioned insertion machine must be prepared for each type, making the manufacture of the waterproof connector 100 difficult. However, in this embodiment, the insulated electric wire 10 constituting the terminal-fitted electric wire 1 is provided with the attachment portion 14, thereby making it possible to maintain a consistent shape and outer diameter of the portion where the rubber stopper 20 is to be installed, regardless of the type or shape of the insulated electric wire 10. Therefore, only one type of rubber stopper 20 is required for multiple types of insulated electric wires 10, allowing for standardization of the rubber stopper 20.

[0019] Next, a method for manufacturing the waterproof connector 100 will be described. First, as shown in FIG. 2(A), a coated electric wire 10 is prepared. Next, a predetermined length of the end (installation position 13) of the front side X1 of the coating 12 is stripped in the axial direction X. The stripped portion and the front end of the coating 12 connected to that portion are placed in a mold, and the mounting portion 14 shown in FIG. 2(B) is formed by resin molding. In this case, as described above, the material for the mounting portion 14 can be pellets made of the same material as the coating 12 or recycled material generated by stripping. That is, the manufacturing method for the terminal-attached electric wire 1 includes a step of molding the mounting portion 14 at the installation position 13 by resin molding using pellets or recycled material. This completes the mounting portion 14.

[0020] The material of the attachment portion 14 may be an insulating resin that undergoes cross-linking when irradiated with an electron beam. Then, a step of irradiating with an electron beam may be added after the step of molding the attachment portion 14 by resin molding. By generating cross-linking in this step, it is possible to, for example, harden the attachment portion 14 and improve the heat resistance of the electric wire with terminal 1. In other words, the manufacturing method of the electric wire with terminal 1 may include a step of hardening the attachment portion 14 by cross-linking through irradiation with an electron beam.

[0021] In the present embodiment, the mounting portion 14 is formed with a main body 15 having an outer diameter smaller than that of the insulated electric wire 10. However, the configuration of the mounting portion 14 is not limited to this. FIGS. 3A to 3C are schematic diagrams corresponding to FIGS. 2A to 2C, illustrating a modified example of the first embodiment. As shown in FIG. 3A, the covering portion 12B of the insulated electric wire 10B has the same outer diameter as that of the covering portion 12 of the insulated electric wire 10. As shown in FIG. 3B, the mounting portion 14B is formed at the installation position 13 with a main body 15B having an outer diameter larger than that of the other portions of the covering portion 12B. The material and molding method of the mounting portion 14B are the same as those in the first embodiment. In this way, the mounting portion 14B may be formed with a main body 15B having an outer diameter larger than that of the other portions of the covering portion 12B. The mounting portion 14B may be provided on multiple types of insulated electric wires 10B, and one type of rubber stopper 20B may be attached thereto, as shown in FIG. 3C.

[0022] According to the first embodiment and the modified example thereof, the attachment portion 14 (attachment portion 14B) having a predetermined outer diameter is integrally formed with the sheath 12, and a rubber stopper 20 (rubber stopper 20B, wire seal) is attached to the attachment portion 14, thereby ensuring close contact between the sheathed electric wire 10 and the rubber stopper 20. Because the attachment portion 14 can be easily molded integrally with the sheath 12 by resin molding or the like, it is possible to easily provide the attachment portion 14 for each of multiple sheathed electric wires 10 having sheaths 12 with different diameters or shapes, for example. Therefore, a versatile sheathed electric wire 10 can be provided, allowing for easy standardization of the rubber stopper 20. Furthermore, with this configuration, for example, a sheathed electric wire that has become unusable due to a change in standards or the like and is no longer compatible with the rubber stopper 20 can be reused by molding a new attachment portion 14. This allows for effective use of excess sheathed electric wire inventory.

[0023] Furthermore, according to the first embodiment and the modified example of the first embodiment, the mounting portion 14 can be formed by resin molding using pellets made of the same material as the covering portion 12, or recycled material obtained by peeling (separating) part of the covering portion 12. This eliminates the need to prepare a special material for the mounting portion 14. This allows for a reduction in the cost of molding the mounting portion 14.

[0024] Furthermore, according to the first embodiment and the modified example of the first embodiment, it is possible to manufacture an electric wire with terminal 1 including a versatile coated electric wire 10 that allows the rubber plug 20 to be easily standardized.

[0025] Furthermore, according to the first embodiment and the modified example of the first embodiment, the attachment portion 14 can be molded by a simple method such as resin molding, and the electric wire with terminal 1 that uses the same rubber plug 20 can be easily manufactured.

[0026] According to the first embodiment and the modified example of the first embodiment, when manufacturing the electric wire with terminal 1, cross-linking is caused by electron beam irradiation, hardening the attachment portion 14, thereby improving the heat resistance of the coated electric wire 10, etc.

[0027] Next, a second embodiment will be described. FIGS. 4A to 4C are side views of the second embodiment, corresponding to FIGS. 2A to 2C. As shown in FIG. 4B, a fitting portion 14C is formed in a covering portion 12C constituting a covered electric wire 10C of the second embodiment. The fitting portion 14C has a configuration corresponding to the above-described fitting portion 14 and includes a main body portion 15C having the same outer diameter as the above-described main body portion 15. In the fitting portion 14C, a first restricting portion 15C1 is formed at an end portion of the front side X1 of the main body portion 15C (one side in the axial direction X of the main body portion 15C). The first restricting portion 15C1 has a flange shape and protrudes radially outward from the outer peripheral surface of the main body portion 15C. As shown in FIG. 4C, a surface 16 facing the rear side X2 abuts against a surface 22b of the rubber plug 20 facing the front side X1 (one end portion in the axial direction X). 4(B), a second restricting portion 15C2 is formed at the end of the rear side X2 of the main body 15C (the other side in the axial direction X of the main body 15C). The second restricting portion 15C2 is flange-shaped and protrudes radially outward from the outer peripheral surface of the main body 15C, and its surface 17 facing the front side X1 abuts against a surface 21b (the other end in the axial direction X) of the rubber stopper 20 facing the rear side X2. The rubber stopper 20 has the same inner diameter as the rubber stopper 20 of the first embodiment.

[0028] With this configuration, the first restricting portion 15C1 restricts the displacement of the rubber stopper 20 circumferentially covering the main body 15C toward the front side X1, and the second restricting portion 15C2 restricts the displacement of the rubber stopper 20 toward the rear side X2. This accurately defines the position of the rubber stopper 20, reliably preventing the rubber stopper 20 from displacing or falling off. The first restricting portion 15C1 or the second restricting portion 15C2 may be omitted. However, omitting the first restricting portion 15C1 or the second restricting portion 15C2 may result in the following problems. FIGS. 5A to 5D are side views showing the displacement of a wire seal in a waterproof connector that does not have a first restricting portion or a second restricting portion. In this connector, the first restricting portion 15C1 and the second restricting portion 15C2 are not formed on the insulated electric wire A. In this configuration, the sheath crimping portion B1 of the crimp terminal B may become loose due to temperature changes that occur when a thermal shock test is performed on the connector, vibrations, or deterioration over time.

[0029] As the sheath crimping portion B1 loosens, the rubber stopper 20 is displaced toward the rear side X2 indicated by the white arrow as shown in FIG. 5B, making it difficult to maintain close contact between the sheathed electric wire A and the rubber stopper 20. Furthermore, if the rubber stopper 20 is further displaced from this state, the rubber stopper 20 falls off the housing 2 as shown in FIGS. 5C-5D, causing the rubber stopper 20 to lose close contact with the housing 2. This reduces or eliminates the waterproofness of the connector. Furthermore, the position of the rubber stopper 20 relative to the sheathed electric wire A may require a positional accuracy of ±0.5 mm. In this case, in a configuration without the first restricting portion 15C1 and the second restricting portion 15C2, the rubber stopper 20 may become misaligned when the sheath crimping portion B1 is crimped. If the rubber stopper 20 is crimped while still misaligned, installation problems may occur, which may result in a decrease in waterproofness. For the above reasons, from the viewpoint of maintaining waterproofness, it is preferable that the first restricting portion 15C1 and the second restricting portion 15C2 are molded without being omitted.

[0030] Next, a first modified example of the second embodiment will be described. FIGS. 6A to 6C are side views corresponding to FIGS. 2A to 2C of the first modified example of the second embodiment. In the first modified example, as shown in FIG. 6A, the outer diameter of the covering portion 12D constituting the covered electric wire 10D is smaller than the outer diameter of the covering portion 12 of the first embodiment. In this configuration, as shown in FIG. 6B, an attachment portion 14D including a main body portion 15D having an outer diameter larger than that of other portions of the covered electric wire 10D is formed at the installation position 13. The attachment portion 14D has a configuration corresponding to the above-described attachment portion 14, and the main body portion 15D has the same outer diameter as the above-described main body portion 15. A first restricting portion 15D1 is formed at an end of the front side X1 of the main body portion 15D, and a second restricting portion 15D2 is formed at an end of the rear side X2 of the main body portion 15D. The first and second restricting portions 15D1 and 15D2 correspond to the first and second restricting portions 15C1 and 15C2, respectively. As shown in FIG. 6C, the rubber stopper 20 surrounds the main body 15D in the circumferential direction about the axis, is sandwiched in the axial direction X between the first and second restricting portions 15D1 and 15D2, and is attached in a compressed state in the axial direction X. Due to this attachment, the second restricting portion 15D2 is slightly bent toward the rear side X2 due to a force that causes the rubber stopper 20 to return to its pre-compression state. The rubber stopper 20 has the same inner diameter as the rubber stopper 20 of the first embodiment.

[0031] This configuration can achieve the same effects and advantages as the second embodiment. Furthermore, by sandwiching the rubber stopper 20 between the first restricting portion 15D1 and the second restricting portion 15D2 and compressing it, displacement of the rubber stopper 20 can be further suppressed. When the outer diameter of the main body portion 15D (attachment portion 14D) is larger than that of the other portions of the sheath portion 12D, as in this modification, this sheath portion 12D may be referred to as a small-diameter sheath for convenience. In other words, the sheath portion 12D whose outer diameter is smaller than that of the main body portion 15D (attachment portion 14D) that is continuous with the attachment portion 14D is referred to as a small-diameter sheath. According to the first modification, in the sheathed electric wire 10D having the sheath portion 12D as a small-diameter sheath, the attachment portion 14D with a larger diameter is formed at the installation position 13, which contributes to the standardization of the rubber stopper 20 and the improvement of the waterproofness of the waterproof connector 100.

[0032] Next, a second modified example of the second embodiment will be described. FIGS. 7A to 7C are side views corresponding to FIGS. 2A to 2C of the second modified example of the second embodiment. In the second modified example, as shown in FIG. 7A, the outer diameter of the covering portion 12E constituting the covered electric wire 10E is larger than the outer diameter of the covering portion 12 of the first embodiment. In this configuration, as shown in FIG. 7B, a mounting portion 14E including a main body portion 15E having a smaller outer diameter than the other portions of the covering portion 12E is formed at the installation position 13. The mounting portion 14E has a configuration corresponding to the mounting portion 14 described above, and the main body portion 15E has the same outer diameter as the main body portion 15 described above. A first restricting portion 15E1 is formed at an end of the front side X1 of the main body portion 15E, and a second restricting portion 15E2 is formed at an end of the rear side X2 of the main body portion 15E. The first restricting portion 15E1 and the second restricting portion 15E2 correspond to the above-described first restricting portion 15C1 and second restricting portion 15C2, respectively.

[0033] In the second modified example, a sloping portion 15E3 is formed, the diameter of which gradually increases from the rear X2 portion of the main body portion 15E toward the second restricting portion 15E2. As shown in FIG. 7(C), the rubber stopper 20 surrounds the main body portion 15E in the circumferential direction around the axis and is attached by being sandwiched in the axial direction X between the first restricting portion 15E1 and the second restricting portion 15E2. The rubber stopper 20 has the same inner diameter as the rubber stopper 20 of the first embodiment. This configuration can achieve the same effects and advantages as the first modified example described above. Furthermore, with this configuration, the sloping portion 15E3 is formed, so that the rubber stopper 20 circumferentially covering the main body portion 15E becomes more difficult to pass through the main body portion 15E in the axial direction X as it approaches the second restricting portion 15E2. Therefore, the sloping portion 15E3 can restrict movement of the rubber stopper 20 in the axial direction X. It should be noted that the configuration is not limited to that of the second modified example, and the inclined portion 15E3 may be formed so as to gradually increase in diameter toward the first restricting portion 15E1.

[0034] Alternatively, both the inclined portion 15E3 whose diameter increases toward the second restricting portion 15E2 and the inclined portion 15E3 whose diameter increases toward the first restricting portion 15E1 may be formed. As described above, the covering portion 12D of the first modified example shown in FIG. 6 is a small-diameter covering. In contrast, the covering portion 12E of the second modified example is a large-diameter covering because the outer diameter of the portion continuing to the mounting portion 14E is larger than the outer diameter of the main body 15E (mounting portion 14E). This allows the covering portion 12E of the insulated electric wire 10E having the covering portion 12E as a large-diameter covering to have the mounting portion 14E with a reduced diameter formed at the installation position 13, contributing to the sharing of the rubber stopper 20 and the improvement of the waterproofness of the waterproof connector 100.

[0035] Next, a third modified example of the second embodiment will be described. FIGS. 8A to 8C are side views corresponding to FIGS. 2A to 2C of the third modified example of the second embodiment. In the third modified example, as shown in FIG. 8A, the outer diameter of the covering portion 12F constituting the covered electric wire 10F is smaller than the outer diameter of the covering portion 12 of the first embodiment. In this configuration, as shown in FIG. 8B, an attachment portion 14F including a main body portion 15F having a larger outer diameter than the other portions is formed at the installation position 13. The attachment portion 14F has a configuration corresponding to the above-described attachment portion 14, and the main body portion 15F has the same outer diameter as the above-described main body portion 15. That is, the covered electric wire 10F of the third modified example is a small-diameter electric wire. A first restricting portion 15F1 is formed at the end of the front side X1 of the main body portion 15F, and a second restricting portion 15F2 is formed at the end of the rear side X2 of the main body portion 15F. The first restriction portion 15F1 and the second restriction portion 15F2 correspond to the above-described first restriction portion 15C1 and second restriction portion 15C2, respectively.

[0036] In this modification, an inclined portion 15F3 is formed, the diameter of which gradually increases from the rear side X2 portion of the main body 15F toward the second restricting portion 15F2. The inclined portion 15F3 corresponds to the inclined portion 15E3 described above. As shown in FIG. 8(C), the rubber stopper 20 has the same inner diameter as the rubber stopper 20 of the first embodiment, surrounds the main body 15F in the circumferential direction about the axis, and is attached by being sandwiched in the axial direction X between the first restricting portion 15F1 and the second restricting portion 15F2. With this configuration, even with a coated electric wire 10F as a small-diameter electric wire, the same functions and effects as those of the second modification described above can be achieved.

[0037] As described above, the first embodiment and the first to third modified examples of the second embodiment have the following advantages. That is, the fitting portion 14 (fitting portion 14C, fitting portion 14E) can be easily formed by reducing the diameter of a portion of the covered electric wire 10 (covered electric wire 10C, covered electric wire 10E) having a large-diameter covering (covering portion 12, etc.) by resin molding or the like. Also, the fitting portion 14D (fitting portion 14F) can be easily formed by increasing the diameter of a portion of the covered electric wire 10D (covered electric wire 10F) having a small-diameter covering (covering portion 12D, etc.) by resin molding or the like. That is, the fitting portion 14, fitting portion 14C, fitting portion 14D, fitting portion 14E, fitting portion 14F can be easily provided for each of a plurality of covered electric wires 10, covered electric wires 10C, covered electric wires 10D, covered electric wires 10E, and covered electric wires 10F having different diameters. In this case, as described above, since the main body 15, the main body 15C, the main body 15D, the main body 15E, and the main body 15F have the same outer diameter, it is possible to use only one type of rubber stopper 20. In other words, regardless of the types of the coating 12, the coating 12C, the coating 12D, the coating 12E, the coating 12F, etc., the rubber stopper 20 can be shared by multiple coated electric wires 10, 10C, 10D, 10E, and 10F.

[0038] The above-described embodiment and modified examples merely illustrate one aspect of the insulated electric wire 10, the electric wire with terminal 1, and the manufacturing method of the electric wire with terminal 1, and the aspect is not limited thereto. For example, in the above-described embodiment and modified examples, the mounting portion 14 is formed at the end of the front side X1 of the covering portion 12, but the mounting portion 14 may be formed at any position on the insulated electric wire 10 without being limited to this end. Furthermore, the connection target of the electric wire with terminal 1 may be any structure other than the housing 2. Furthermore, the rubber stopper 20 is merely an example, and a member having various shapes and materials that function as a wire seal may be installed instead of the rubber stopper 20. Furthermore, the structures described in the first to third modified examples of the second embodiment as described above may be used alone or in combination of two or more of them. [Explanation of symbols]

[0039] 10. Insulated wire 11 Core section 12 Covering part 13 Installation position 20 Rubber plug (wire seal)

Claims

1. A coated electric wire including a core portion and a coating portion that circumferentially covers the core portion, The covering portion is provided with an attachment portion for inserting a cylindrical wire seal therethrough to support the wire seal, The insulated electric wire is characterized in that the attachment portion is formed integrally with the covering portion by resin molding and is formed into a cylindrical shape with a different outer diameter from that of a portion of the covering portion other than the attachment portion.

2. The covering portion is a large-diameter coating having an outer diameter of a portion continuous with the mounting portion that is larger than an outer diameter of the mounting portion; 2. The insulated electric wire according to claim 1, wherein the outer diameter of the portion continuing to the mounting portion is smaller than the outer diameter of the mounting portion.

3. The mounting portion is a main body portion extending in the axial direction of the core portion and abutting against an inner circumferential surface of the wire seal; a first restricting portion that is located on the one axial side of the main body portion and that abuts against an end portion of the wire seal on the one axial side; 2. The insulated electric wire according to claim 1, further comprising: a second restricting portion that is disposed on the other axial side of the main body and abuts against an end portion of the wire seal on the other axial side.

4. The insulated electric wire according to claim 3 , wherein the main body portion is provided with an inclined portion whose diameter increases toward the first restricting portion or the second restricting portion.

5. A terminal-attached electric wire comprising: the coated electric wire according to claim 1; the wire seal; and a terminal.

6. A method for manufacturing an electric wire with a terminal according to claim 5, A method for manufacturing an electric wire with a terminal, comprising a step of molding the attachment portion by resin molding at a predetermined position on the coating portion using pellets made of the same material as the coating portion, or recycled material obtained by separating a portion of the coating portion.

7. The method for manufacturing an electric wire with a terminal according to claim 6, further comprising the step of curing the mounting portion by cross-linking it with electron beams after the step of forming the mounting portion.

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