Electric wire with terminal, wire harness, and method for manufacturing electric wire with terminal

Abstract

A wire (10) with a terminal is configured by electrically connecting a terminal (1) and a covered conductor (11). A crimping portion (5) of the terminal (1) is a portion that is crimped to the covered conductor (11), and has a conductor crimping portion (7) that crimps a conductor (13) that is exposed from a covering portion (15) of the covered conductor (11) on a front end side, and a covering crimping portion (9) that crimps the covering portion (15) of the covered conductor (11). The covered conductor (11) has a tensile strength body (17) that is disposed at substantially the center of a cross section, and the conductor (13) that is configured by a plurality of conductors disposed on the outer periphery of the tensile strength body (17). The tensile strength body (17) is configured by a plurality of strands. The conductor (13) is crimped from the entire circumference of the conductor (13) in the conductor crimping portion (7). It is preferable that the tensile strength of the tensile strength body (17) be higher than the tensile strength of the conductor (13).

Description

Technical Field

[0001] This invention relates to terminald wires, for example, used in automobiles and the like. Background Technology

[0002] Typically, automotive wiring harnesses are bundled together after the crimp terminals are connected to the conductors of the covered wires, and are arranged as signal lines for vehicles, etc. Regarding typical covered wires and crimp terminals, the coating at the front end of the covered wire is removed, and the exposed conductor and wire crimp portion are crimped together, with the covered portion crimped within the covered crimp portion to form a connection. At this time, although an oxide film with poor conductivity forms on the surface of the conductor, this oxide film can be broken by applying strong compression when tightening the wire crimp portion. Therefore, the strands constituting the conductor contact the wire crimp portion of the crimp terminal, and conductivity is achieved between the strands and the crimp terminal.

[0003] However, especially in automotive wiring harnesses, thinner wires are sometimes used for weight reduction, requiring 0.35sq (sq refers to mm). 2 For wires with a diameter of less than 10 mm, there is a problem that the tensile strength of the connection is significantly reduced due to strand breakage or damage caused by excessive compression. However, if the compression is reduced, as mentioned above, the oxide film is not sufficiently destroyed, resulting in an increase in the resistance of the connection.

[0004] In other words, strong compression damages the strands, easily reducing the strength of the crimped joint. Weak compression, however, results in insufficient oxide film breakdown, increased resistance at the crimped joint, and pull-out due to inadequate crimping, thus failing to guarantee the strength of the crimped joint. Therefore, especially in thin-diameter coated wires, it is difficult to control the balance between conductivity and tensile strength solely through compression ratio. Consequently, a connector that allows for easy control of the balance between conductivity and tensile strength using compression ratio in a single crimping operation is desired.

[0005] In response, wires with tensile strength elements have been studied. For example, when using wires made of conductors with a tensile strength of about 30N, in order to ensure a tensile strength exceeding the 80N required for automotive wiring, a wire with a tensile strength element has been proposed, in which the conductor is spirally wound around the outer periphery of a metallic or non-metallic tensile strength element. Such a wire is produced by stripping the conductor to expose the tensile strength element and inserting it into a sleeve, crimping the tensile strength element using steel clamps, then integrating it with a curable resin such as an adhesive, and crimping the conductor portion using clamps such as aluminum (Patent Document 1).

[0006] In addition, a type of sheathed wire has been proposed, which is provided with a conductor portion made of multiple strands bundled together, and fibrous tensile strength bodies are provided on the outer periphery of the conductor portion, the inner periphery of the sheathing material, and in the valleys between the strands (Patent Document 2).

[0007] Existing technical documents

[0008] Patent documents

[0009] Patent Document 1: Japanese Utility Model Application Publication No. 61-046827

[0010] Patent Document 2: Japanese Patent Application Publication No. 2012-3856 Summary of the Invention

[0011] The problem that the invention aims to solve

[0012] However, in both Patent Document 1 and Patent Document 2, for example, when using thick-diameter coated wires to connect with crimp terminals, although crimping at the wire crimping point can be performed with a compression ratio that balances connection strength and connection resistance, the appropriate range of crimping conditions for both connection strength and resistance narrows as the wire diameter decreases. This is because, as mentioned above, when ensuring connection strength, the conductor breaks and the connection resistance increases; when focusing on connection resistance, connection strength cannot be obtained, and this becomes the main cause of wire detachment. Thus, the thinner the wire diameter, the more difficult it is to balance connection strength and resistance.

[0013] Furthermore, for example, in Patent Document 1, if the compression ratio during crimping is low (i.e., strong compression), the tensile strength is reduced due to damage to the tensile material; conversely, if the compression ratio during crimping is high (i.e., low compression), the resistance of the crimped section increases. In particular, if crimping is performed in an open cylindrical shape, the conductor and tensile material become scattered during crimping, resulting in reduced tensile strength and increased resistance at the crimped section. Additionally, in existing wire connections with tensile materials, separate crimping processes are required, including stripping, crimping the tensile material, and crimping the wire. This increases the number of components, operation time, and cost. Especially if the wire diameter becomes thinner, stripping itself becomes difficult. Thus, in Patent Document 1, the manufacturing process becomes more complex, leading to increased processing costs.

[0014] Furthermore, Patent Document 2 discloses an example of increasing strength without reducing electrical properties by having a fibrous tensile body between the conductors. However, when crimping the wires of Patent Document 2, the resistance of the crimped section may increase because the tensile body enters between the conductor and the terminal. Even assuming the tensile body is a conductor, a gap will be created between the tensile body and the conductor due to the difference in thermal expansion coefficients when a temperature change is applied, thus increasing the crimping resistance. Thus, like Patent Document 1, Patent Document 2 fails to solve the problem that if the compression ratio during crimping is low, the tensile body will be damaged and the tensile strength will decrease; if the compression ratio during crimping is high, the resistance of the crimped section will increase.

[0015] The present invention was made in view of the following problems, and its object is to provide terminald wires, etc., that have good crimping workability and can balance connection strength and connection resistance.

[0016] Methods for solving problems

[0017] To achieve the above objectives, the first invention provides a terminal wire, which is electrically connected to a covered conductor and a terminal. The covered conductor has a tensile strength body and a conductor disposed around the periphery of the tensile strength body and composed of a plurality of conductors. The cross-sectional area of ​​the conductor is 0.35 sq or less, and the tensile strength of the tensile strength body is higher than the tensile strength of the conductor. The terminal has: a conductor crimping portion that crimps the conductor exposed from the covered portion at the front end of the covered conductor; and a covered crimping portion that crimps the covered portion of the covered conductor, wherein the conductor is crimped in the conductor crimping portion from the entire circumference of the conductor.

[0018] Alternatively, the tensile body may be composed of multiple strands of wire.

[0019] Preferably, the compression rate of the conductor is less than or equal to the compression rate of the area where the tensile body is disposed.

[0020] Alternatively, the wire may be twisted around the periphery of the tensile body.

[0021] Alternatively, at least the front end of the conductor may be compressed from the outer peripheral side.

[0022] Alternatively, a plating process can be performed on the conductor.

[0023] Preferably, the conductor is crimped around the entire circumference at a predetermined position in the axial direction by the conductor crimping portion.

[0024] Preferably, the wire crimping portion does not contact the tensile body.

[0025] Alternatively, the cross-sectional area of ​​the conductor may be less than 0.35 sq.

[0026] According to the first invention, in a cross-section perpendicular to the length direction of the covered conductor, a conductor is disposed on the outer periphery of the tensile body. Therefore, when the conductor is crimped using the conductor crimping portion, the conductor can reliably contact the conductor crimping portion and achieve conductivity. Furthermore, in the conductor crimping portion, crimping is performed from the entire circumference of the conductor, thus suppressing localized stress (deformation) on the conductor during crimping and ensuring the contact area between the conductor and the conductor crimping portion.

[0027] Furthermore, the tensile strength of the conductor is ensured by the central tensile body. Unlike in the past, there is no need to use different clamps to connect the tensile body to the conductor, thus reducing the number of parts and simplifying the connection process.

[0028] The aforementioned effect is particularly effective when using covered conductors with a cross-sectional area of ​​0.35 sq or less, and more specifically, when using covered conductors with a cross-sectional area of ​​0.3 sq or less.

[0029] Furthermore, since the tensile strength of the tensile conductor is higher than that of the wire, deformation of the tensile conductor is suppressed during compression, thus preventing a decrease in the tensile strength of the wire. In this case, if the tensile conductor is composed of multiple strands, during compression, irregularities are formed on the outer periphery of the tensile conductor through the strands. Therefore, for the wire, even with the same amount of deformation, compared to deformation on the outer periphery of a single tensile conductor, a portion of the wire can deform while entering the irregularities, thus preventing excessive flattening of the wire.

[0030] Furthermore, when crimping the conductor crimp section, the high tensile strength of the tensile resistive body ensures that the conductor's compression rate is less than or equal to the apparent compression rate of the area where the tensile resistive body is located. Therefore, deformation of the tensile resistive body can be suppressed, and reliable compression deformation of the conductor can be achieved.

[0031] In addition, if the conductor is twisted around the periphery of the tensile body, the occurrence of conductor unraveling can be suppressed.

[0032] Similarly, by compressing the front end of the wire from the outer periphery to form a terminal processing section, wire scattering can be suppressed when the front end of the wire is inserted into the tubular wire crimping section.

[0033] Furthermore, plating the surface of the conductor with a conductive metal is effective in improving conductivity and tensile strength. Additionally, it offers an improvement in workability, such as reducing the scattering of conductor strands during wire crimping.

[0034] In addition, by crimping the wire from the full circumference at a specified axial position of the wire crimping portion, it is possible to more reliably suppress localized stress on the wire during crimping and ensure the contact area between the wire and the wire crimping portion.

[0035] Furthermore, by crimping in a manner where the wire crimp portion does not contact the tensile strength, conductor alignment irregularities can be suppressed, reliable contact between the wire and the crimp portion can be ensured, and reliable compression of both the wire and the tensile strength can be achieved. For example, in the case of crimping where the coil is forcefully bitten into the center of the cross-section due to the open cylindrical shape, the cross-sectional shape of the wire changes drastically, and neither the wire nor the tensile strength reduces the compression ratio, making it difficult to ensure the desired performance. Moreover, by preventing the wire crimp portion from contacting the tensile strength, damage to the tensile strength at the wire crimp portion can be prevented.

[0036] The second invention is a wire harness, characterized in that the wire harness is integrally formed of a plurality of terminal wires including the terminal wires of the first invention.

[0037] According to the second invention, it is possible to obtain a wire bundle consisting of multiple thin-diameter wires.

[0038] The third invention is a method for manufacturing a terminal wire, which manufactures the terminal wire of the first invention. The method is characterized in that, when crimping the wire crimping portion, in the initial stage of compression, both the compression ratio of the wire and the apparent compression ratio of the tensile body decrease. Subsequently, as compression continues, the decrease in the apparent compression ratio of the tensile body becomes relatively smaller, and the main reduction is in the compression ratio of the wire.

[0039] According to the third invention, the covered conductor and the terminal can be easily crimped using the same process as conventional terminald wires. For example, the compressibility of the tensile body and the conductor decreases simultaneously in the initial stage of compression, but the tensile body reaches its compression limit first, after which the compressibility is difficult to decrease further, thus easily creating a difference in compressibility between the tensile body and the conductor. In crimping where such a difference in compressibility occurs, the compressibility of the conductor can be reduced while maintaining a high compressibility of the tensile body, making it particularly effective for conductors requiring strong crimping to reduce the resistance of the crimped section. Furthermore, even in crimping where the compressibility of the tensile body and the conductor are equal, since the tensile body is not excessively flattened, higher tensile strength than in the prior art can be exhibited.

[0040] Invention Effects

[0041] According to the present invention, it is possible to provide wires with terminals that have good crimping performance and can balance connection strength and connection resistance. Attached Figure Description

[0042] Figure 1 This is a perspective view showing the wire 10 with terminals.

[0043] Figure 2A This is an axial cross-sectional view showing the wire 10 with terminals.

[0044] Figure 2B This is a radial sectional view of the wire crimping part 7.

[0045] Figure 3 This is a diagram showing the terminal 1 and the covered wire 11 before crimping.

[0046] Figure 4A This is a diagram showing the front end of conductor 13.

[0047] Figure 4B This is a diagram showing the configuration of the terminal processing unit 19.

[0048] Figure 4C This is a diagram showing the configuration of the terminal processing unit 19.

[0049] Figure 4D This is a diagram showing the configuration of the terminal processing unit 19.

[0050] Figure 5 This is a diagram showing other configurations of the terminal processing unit 19.

[0051] Figure 6A This is a schematic diagram showing the changes in the wire crimping portion 7 during the crimping process.

[0052] Figure 6B This is a schematic diagram showing the changes in the wire crimping portion 7 during the crimping process.

[0053] Figure 6C This is a schematic diagram showing the changes in the wire crimping portion 7 during the crimping process.

[0054] Figure 7 This is a schematic diagram showing the crimped portion 7 of the wire after crimping.

[0055] Figure 8 This is a diagram showing the terminal 1a before crimping and the covered wire 11.

[0056] Figure 9A This is a top view showing the wire 10a with terminals.

[0057] Figure 9B yes Figure 9A A sectional view along line AA.

[0058] Figure 9C yes Figure 9A BB line section view.

[0059] Figure 10A This is another radial cross-sectional view of the wire crimping part 7.

[0060] Figure 10B This is another radial cross-sectional view of the wire crimping part 7.

[0061] Figure 10C This is another radial cross-sectional view of the wire crimping part 7.

[0062] Figure 11A This is a diagram showing the cross-section of other covered conductors 11.

[0063] Figure 11B This is a diagram showing the cross-section of other covered conductors 11. Detailed Implementation

[0064] (First Embodiment)

[0065] Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings. Figure 1 This is a perspective view showing the wire 10 with terminals. Figure 2A This is an axial cross-sectional view of the wire 10 with terminals. Figure 2B This is a radial cross-sectional view of the wire crimping portion 7. The terminald wire 10 is formed by electrically connecting the terminal 1 and the covered wire 11.

[0066] The sheathed conductor 11 is composed of, for example, a conductor 13 made of copper, copper alloy, aluminum, or aluminum alloy and a sheathing portion 15 covering the conductor 13. That is, the sheathed conductor 11 has a sheathing portion 15 and a conductor 13 protruding from the front end of the sheathing portion 15.

[0067] Terminal 1 is made of, for example, copper, copper alloy, aluminum, or aluminum alloy. A covered wire 11 is connected to terminal 1. Terminal 1 is configured such that terminal body 3 and crimping portion 5 are connected via transition portion 4.

[0068] The terminal body 3 is a component formed by shaping a plate-like material of a predetermined shape into a cylindrical body with a rectangular cross-section. The terminal body 3 has an elastic contact piece inside, formed by folding the plate-like material into the rectangular cylindrical body. The terminal body 3 is used for connection by inserting a male terminal or the like into the front end. Furthermore, in the following description, an example of a female terminal is shown where the terminal body 3 allows the insertion of a male terminal or the like through an insertion tab (not shown). However, in this invention, the shape of the details of the terminal body 3 is not particularly limited. For example, an insertion tab for a male terminal may be provided instead of a female terminal body 3, and a bolt fastening portion such as a circular terminal may also be provided.

[0069] The crimping portion 5 of terminal 1 is the part that crimps the covered wire 11. This crimping portion 5 includes: a wire crimping portion 7, which crimps the wire 13 exposed from the covered portion 15 at the front end of the covered wire 11; and a covering crimping portion 9, which crimps the covered portion 15 of the covered wire 11. That is, the wire 13 exposed after the covered portion 15 is peeled off is crimped by the wire crimping portion 7, and the wire 13 is electrically connected to terminal 1. Furthermore, the covered portion 15 of the covered wire 11 is crimped by the covering crimping portion 9 of terminal 1. In this embodiment, the wire crimping portion 7 and the covering crimping portion 9 are each configured as a tubular (generally cylindrical) shape that is closed in the circumferential direction.

[0070] Alternatively, serrations (not shown) can be provided along the width direction (perpendicular to the length direction) in a portion of the inner surface of the wire crimping portion 7. By forming serrations in this way, the oxide film on the surface of the wire 13 can be easily broken during crimping, and the contact area with the wire 13 can be increased.

[0071] like Figure 2BAs shown, the sheathed conductor 11 has a tensile body 17 disposed approximately at the center of its cross-section and conductors 13 composed of multiple conductors disposed around the periphery of the tensile body 17. The tensile body 17 is a component that bears tension for tensile loads. Further details will be described later, but the tensile body 17 is composed of multiple strands. Additionally, the conductors 13 may be helically twisted along the length of the sheathed conductor 11 at the periphery of the tensile body 17. In this case, each conductor 13 (strand) disposed around the periphery of the tensile body 17 may also be conductors 13 (strands) of the same shape with the same cross-sectional area. For example, the conductor 13 may be soft copper wire, hard copper wire, copper alloy wire, aluminum wire, aluminum alloy wire, etc., but from the viewpoint of electrical conductivity, soft copper wire is preferred.

[0072] As described above, the wire crimping portion 7 is tubular. Therefore, at a predetermined axial position (cross-section of the predetermined position) in the wire crimping portion 7, the wire crimping portion 7 can crimp the wire 13 from its entire circumference 360°. That is, the wire 13 is crimped from its entire circumference in the wire crimping portion 7. Therefore, the inner surface of the wire crimping portion 7 is in contact with the wire 13 in the entire circumferential direction, and during crimping, it is also possible to suppress the generation of local stress (deformation) on the wire 13.

[0073] Here, the present invention is particularly effective when the cross-sectional area of ​​the conductor 13 (total cross-sectional area of ​​the strands) is 0.35 sq or less. That is, the terminal 1 can crimp the conductor 13 with a cross-sectional area of ​​0.35 sq or less. Furthermore, the cross-sectional area of ​​the conductor 13 (total cross-sectional area of ​​the strands) is preferably 0.3 sq or less, in which case the terminal 1 is preferably capable of crimping the conductor 13 with a cross-sectional area of ​​0.3 sq or less. In addition, since the conductor 13 is used with the tensile strength body 17, the cross-sectional area of ​​the conductor 13 can also be 0.05 sq or less. The smaller the cross-sectional area of ​​the conductor 13, the greater the effect of this embodiment. Furthermore, from the viewpoint of ensuring crimp strength, the cross-sectional area of ​​the conductor 13 is preferably 0.01 sq or more, and more preferably 0.03 sq or more.

[0074] Furthermore, the tensile body 17 can be a metal wire such as steel wire, or a resin or fiber-reinforced resin, or it can be composed of multiple strands bundled together. For example, PBO (poly(p-phenylenebenzobisoxazole)) fiber, aromatic polyamide fiber, carbon steel wire, stainless steel wire, liquid crystal polyester fiber, glass fiber, carbon fiber, etc., can be used as the strands constituting the tensile body 17, but considering corrosion resistance, non-metallic wire is preferred.

[0075] Furthermore, the tensile strength of the tensile body 17 is preferably higher than that of the conductor 13. While tensile strength refers to the maximum stress at which fracture occurs under tensile stress, in this embodiment, it is defined as a relative indicator of the ease of fracture due to the flattening of the material during crimping. That is, the tensile body 17 is made of a material that is less prone to deformation during crimping compared to the conductor 13. Additionally, the Young's modulus of the tensile body 17 is preferably higher than that of the conductor 13, and the yield stress (or yield strength) of the tensile body 17 is preferably higher than that of the conductor 13.

[0076] Next, the manufacturing method of the wire 10 with terminals will be described. Figure 3 This is a perspective view showing the terminal 1 and the covered wire 11 before crimping. As described above, the terminal 1 has a terminal body 3 and a crimping portion 5. The crimping portion 5 is integrally formed into a generally cylindrical shape by the wire crimping portion 7 and the covered crimping portion 9. For example, the crimping portion 5 can be formed by rounding a plate component and butting its ends together, joining them in the longitudinal direction by welding or brazing, or by unfolding a tubular component to form the terminal 1. In addition, the wire crimping portion 7 and the covered crimping portion 9 can have the same diameter, but as shown in the figure, the inner diameter of the covered crimping portion 9 can also be larger than the inner diameter of the wire crimping portion 7.

[0077] First, as described above, the covering portion 15 at the front end of the conductor 11 is peeled off to expose the conductor 13 at the front end. Next, as... Figure 4A As shown, a terminal processing section 19 can be formed at the front end of the wire 13 before it is inserted into the crimping portion 5 of the terminal 1. The terminal processing section 19 is a processing section integrated in such a way that the individual strands of the wire 13 do not separate.

[0078] As described above, the tensile body 17 is positioned approximately in the center, with conductors 13 arranged around its periphery. The conductors 13 are composed of multiple conductors. In such a case, as... Figure 4B As shown, by compressing at least the front end of the conductor 13 from the outer periphery, a terminal processing section 19 can be formed. In this way, by compressing the front end of the conductor 13 from the outer periphery, strand unraveling can be suppressed, making it easier to insert into the tubular crimping section 5.

[0079] In addition, such as Figure 4C As shown, at least the front end of the conductor 13 can also be plated together, forming the terminal processing section 19 through the plating layer 21. In this way, by plating the front end of the conductor 13 from the outer periphery, strand fraying can be suppressed, making it easier to insert into the tubular crimping section 5.

[0080] Furthermore, when plating is performed on the outer circumference of the conductor 13, the temperature can sometimes be high depending on the plating method. With such a plating method, when the conductors 13 are twisted together and then plated together, the tensile body 17 may deteriorate due to heat, and the tensile strength may decrease.

[0081] In such a situation, such as Figure 4D As shown, a plating layer 21 can also be formed on each conductor and then twisted to the outer periphery of the tensile body 17. Additionally, as... Figure 5 As shown, plating layer 21 can also be formed on each conductor, and then plating treatment can be performed on the front ends of multiple conductors together from the outer perimeter. In this case, the type of plating for each conductor and the type of plating together can also be changed. As mentioned above, by performing plating together, conductor scattering can be suppressed, but if the conductors are bundled together and plating is performed together, due to the influence of the conductor shape, etc., it is possible to locally produce areas with thicker or thinner plating. In this regard, by performing substrate plating treatment on each conductor in advance, this effect can be reduced, and approximately uniform plating can be performed.

[0082] Furthermore, the terminal processing unit 19 is not limited to methods based on compression and plating. For example, soldering or welding can be used at the tip of the conductor 13 to suppress strand unraveling. Additionally, multiple terminal processing methods, such as compression from the periphery and simultaneous plating, can be used.

[0083] Next, the coated wire 11 with its front end treated as described is inserted into the rear end of the tubular crimping portion 5 of the terminal 1. When the front end of the coated wire 11 is inserted into the crimping portion 5, the exposed portion of the wire 13 is located inside the wire crimping portion 7, and the coated portion 15 is located inside the coated crimping portion 9. At this time, the front end of the wire 13 can also be exposed from the front end of the wire crimping portion 7.

[0084] Figure 6A The central diagram is a schematic cross-sectional view of the wire crimping portion 7 before crimping. The left diagram shows the shape of the region of the tensile body 17, and the right diagram is an enlarged view of the region of the tensile body 17. As described above, the tensile body 17 is formed by bundling together multiple tensile body strands 17a. The wire 13 is disposed around the outer periphery of the tensile body strands 17a.

[0085] Furthermore, the cross-sectional area of ​​the conductor 13 before crimping is the sum of the cross-sectional areas of all conductors. This is the product specification for the conductor 11, and even in image analysis at the cross-section, the total cross-sectional area can be calculated relatively easily. On the other hand, the tensile body strands 17a are thinner than the conductors constituting the conductor 13, making it difficult to clearly distinguish the gaps between the tensile body strands 17a and each other. Therefore, the cross-sectional area of ​​the tensile body 17a before crimping is defined as the area of ​​the tensile body region surrounded by the conductor 13. Figure 6A A in the middle.

[0086] Figure 6B It is during the compression process and Figure 6A The corresponding diagram. When compression begins, deformation occurs in the conductor 13 and the tensile body strands 17a. At this initial stage of deformation, even if the total cross-sectional area of ​​the tensile body strands 17a does not change significantly, the gaps between the tensile body strands 17a decrease, thus increasing the apparent cross-sectional area of ​​the tensile body 17a region ( Figure 6B The compression ratio (A1) in the figure is reduced. That is, when the wire crimping part 7 is crimped, both the compression ratio caused by the deformation of the wire 13 and the compression ratio of the appearance of the tensile body 17 are reduced in the initial stage of compression.

[0087] Figure 6C It is the state when all the pressing is completed. Figure 6A The corresponding figure. As mentioned above, the tensile body strand 17a has higher strength than the conductor 13 and is less prone to deformation. Therefore, after the gap is reduced, the cross-sectional area of ​​the tensile body 17 ( Figure 6C The cross-sectional area of ​​conductor 13 will not decrease significantly; the main change is the deformation of conductor 13 (reduction in cross-sectional area). Furthermore, the cross-sectional area of ​​the compressed tensile body 17 is obtained by subtracting the cross-sectional area of ​​conductor 13 from the internal cross-sectional area of ​​conductor crimping portion 7. Thus, from... Figure 6B Starting from the state, after further compression, the reduction in the compression ratio of the tensile body 17 becomes relatively smaller, mainly reducing the compression ratio of the conductor 13.

[0088] Here, the compression rate of the crimped wire 13 is less than or equal to the compression rate of the area where the tensile strength body 17 is disposed. Furthermore, if the total cross-sectional area of ​​the wire 13 before the crimping process is set to A0 (… Figure 6A The total cross-sectional area of ​​the compressed wire 13 is set as A3. Figure 6C If the compression ratio of conductor 13 is A3 / A0 (%), then the compression ratio of conductor 13 is A3 / A0 (%). Additionally, if the cross-sectional area of ​​the tensile body region before the crimping process is set as A ( Figure 6A Let the cross-sectional area of ​​the compressed tensile body region be A2. Figure 6C If the area containing the tensile strength 17 is compressed, then the apparent compression ratio of the region is A2 / A (%). Therefore, A3 / A0 ≤ A2 / A. Furthermore, the area ratio A3 / A2 of the compressed conductor 13 to the tensile strength 17 can vary depending on the overall compression ratio of the wire.

[0089] As described above, the wire 13 is crimped around its entire circumference in the wire crimping portion 7. Additionally, as... Figure 6CAs shown, the tensile body 17 is formed by multiple tensile body strands 17a, thus creating an uneven surface on the outer periphery of the tensile body 17 (region). Therefore, at the interface between the tensile body 17 and the conductor 13, the conductor 13 deforms according to the uneven surface formed by the tensile body strands 17a. Because the tensile body 17 has an uneven shape, the contact area between the conductor 13 and the tensile body 17 increases, and the frictional force increases. Therefore, for tension, it is easier to transfer force from the conductor 13 to the tensile body 17, and an increase in strength can be anticipated when a tensile force is applied to the conductor 13.

[0090] For example, if the tensile body 17 is a single wire, the interface between the tensile body 17 and the conductor 13 is generally smooth. In this case, since the tensile body 17 is not easily deformed relative to the conductor 13, the conductor 13 deforms by flattening along the surface of the tensile body 17. Therefore, the conductor 13 becomes too thin and may break. In contrast, if an irregularity is formed on the outer peripheral surface of the tensile body 17, the conductor 13 can deform by embedding itself into the irregularity, thus preventing excessive flattening and suppressing breakage.

[0091] Furthermore, since the tensile body 17 (tensile body strand 17a) deforms less than the conductor 13, it is less prone to breakage due to the reduction in cross-sectional area. In particular, since the conductor crimping portion 7 is tubular, the conductor 13 is compressed throughout the entire circumference. The conductor 13 is positioned between the tensile body 17 and the conductor crimping portion 7, and the tensile body 17 does not contact the conductor crimping portion 7, thus preventing damage to the tensile body 17.

[0092] In addition, such as Figure 7 As shown, sometimes the tensile body 17 (tensile body strand 17a) enters between the conductors 13, and a portion of the tensile body 17 contacts the conductor crimping portion 7 (part C in the figure). As described above, it is preferable that the tensile body 17 does not contact the conductor crimping portion 7, but as shown, a portion of the tensile body 17 may also make slight contact with the conductor crimping portion 7. For example, in any cross-section, if the perimeter of the tensile body 17 in contact with the conductor crimping portion 7 within the total outer perimeter of the tensile body 17 is 30% or less, a damage suppression effect of the tensile body 17 can be obtained.

[0093] The above provides a terminal wire 10. Furthermore, a wire harness formed by integrating multiple terminal wires including the obtained terminal wire 10 can be obtained.

[0094] As explained above, according to this embodiment, in the wire crimping portion 7, the wire 13 is crimped from a full 360° circumference, thus suppressing localized stress (deformation) on the wire 13 during crimping. Furthermore, crimping can be performed without significantly damaging the structure of the central tension-resistant body 17 and the wire 13 twisted around it. Additionally, since the wire crimping portion 7 contacts the wire 13 throughout its entire circumference, resistance degradation can also be suppressed.

[0095] Furthermore, since the tensile strength of the tensile body 17 is higher than that of the conductor 13, a stronger crimping can be performed. That is, even with strong crimping, the tensile body 17 will not be damaged, thus preventing the covered conductor 11 from breaking in the conductor crimping portion 7. In addition, by performing strong crimping, the oxide film of the conductor 13 can be broken, allowing the conductor 13 to adhere more reliably to the terminal 1, thus achieving both low resistance and high tensile strength of the crimped portion. Therefore, it is particularly effective for fine wires of 0.35 sq or less.

[0096] Furthermore, since the tensile body 17 is composed of tensile body strands 17a, deformation of the conductor 13 and deformation to eliminate gaps between the tensile body strands 17a occur during the initial crimping stage. Therefore, by applying compressive force only to the conductor 13, moderate compressive deformation can be achieved. Additionally, since the outer peripheral surface of the tensile body 17 has irregularities, the conductor 13 deforms along these irregularities, thus suppressing excessive flattening of the conductor 13.

[0097] Furthermore, in the wire crimping section 7, the terminal 1 (wire crimping section 7) crimps the internal wire 13, and the wire 13 crimps the internal tension body 17 (tension body strand 17a). At this time, if the wire crimping section 7 has sufficient compression, both the frictional force between the terminal 1 (wire crimping section 7) and the wire 13, and the frictional force between the wire 13 and the tension body 17 (tension body strand 17a), are sufficient, thus achieving a high pull-out force. On the other hand, if there is insufficient compression, although the frictional force between the terminal 1 (wire crimping section 7) and the wire 13 can be relatively easily ensured, the frictional force between the wire 13 and the tension body 17 (tension body strand 17a) cannot be sufficiently ensured, thus failing to achieve a high pull-out force. Therefore, in the wire crimping section 7, it is preferable to ensure a sufficiently large compression (low compression ratio) within the range where the wire 13 will not break.

[0098] Furthermore, as in this embodiment, the wire crimping portion 7 is cylindrical. In the case where there is a brazing portion at the joint, the brazing portion, with its low hardness, exerts less compressive stress on the wire 13, making it easier for the tension-resistant body 17 to be pulled out. Therefore, it is preferable to remove the brazing portion or to omit the brazing portion altogether, so that the hardness of the joint formed in the wire crimping portion 7 is equal to the hardness of the material in the wire crimping portion 7.

[0099] (Second Implementation)

[0100] Next, the second embodiment will be described. Figure 8 This is a perspective view of the terminal 1a of the second embodiment before the covered wire 11 is crimped. Furthermore, in the following description, structures that perform the same function as in the first embodiment are labeled with the same meaning. Figures 1 to 6C The same labels are used, and repeated descriptions are omitted.

[0101] Terminal 1a has a structure that is roughly the same as terminal 1, but it differs in that the crimping part 5 is an open cylindrical shape. Terminal 1a can also be crimped in the same way as terminal 1. Figure 9A This is a top view showing a terminald wire 10a obtained by crimping the terminal 1a and the covered wire 11 together.

[0102] Here, in the open cylindrical wire crimping portion 7, at least one pair of opposing cylindrical plates are folded in, and the wire 13 is crimped. In this embodiment, the opposing cylindrical plates are arranged in a staggered configuration relative to the axial direction of the wire crimping portion 7. Alternatively, the covering crimping portion 9 can allow the opposing cylindrical plates to be butted together, or it can be arranged similarly to the wire crimping portion 7, with the cylindrical plates staggered axially.

[0103] In this way, the open cylindrical crimping section with staggered cylindrical plates generally does not damage the object being crimped, and can reliably make the cylindrical plates fit tightly against the object being crimped.

[0104] In addition, in the crimping of tubes arranged in an interlaced pattern, it is sometimes impossible to completely crimp the outer periphery of the conductor 13 throughout the entire circumference. Figure 9B yes Figure 9A AA-line sectional view, Figure 9C yes Figure 9A A BB-line sectional view. For example... Figure 9B , Figure 9C As shown, in a cross-section at a predetermined position in the axial direction of the wire crimping portion 7, a gap 23 is formed on a portion in the circumferential direction that is not crimped by the wire crimping portion 7.

[0105] However, in this case, the gaps 23 are not arranged in a straight line along the axial direction of the wire crimping portion 7, but are formed at different circumferential positions at their respective cross-sectional locations. Therefore, it can be said that the wire 13 is necessarily crimped around its entire circumference at any position along the axial direction of the wire crimping portion 7. For example, Figure 9B The circumferential position of gap 23 in the middle is Figure 9C The cross-section is crimped by the wire crimping part 7. Figure 9C The circumferential position of gap 23 in the middle is Figure 9B The conductor 13 is crimped at the cross-sectional position by the wire crimping part 7. In this way, the entire circumference of the conductor 13 can be crimped at any position of the wire crimping part 7.

[0106] Thus, even if the crimping portion 5 is made into an open cylindrical shape, the same effect as in the first embodiment can be obtained in the wire crimping portion 7. In addition, by making the crimping portion 5 into an open cylindrical shape, it is easy to place the wire 13 in the crimping portion 5.

[0107] Thus, in the wire crimping section 7, as long as the wire 13 is compressed from the entire circumference, the wire crimping section 7 does not need to be tubular. In addition, even in the open cylindrical type wire crimping section 7, the cylindrical pieces can be arranged without staggering, but rather the cylindrical pieces can be arranged opposite each other in the same position relative to the axial direction of the wire crimping section 7.

[0108] For example, Figure 10A This is a cross-sectional view showing an example of crimping in an open cylindrical wire crimping section 7 where the tubes are arranged opposite each other. Figure 10A In the example shown, the cylindrical plates are positioned opposite each other at the same location relative to the axial direction of the wire crimping portion 7, and are crimped in such a way that the cylindrical plates overlap each other. That is, the opposing cylindrical plates overlap each other, and one cylindrical plate is crimped in such a way that it wraps around the other cylindrical plate.

[0109] In addition, such as Figure 10B As shown, the front ends of the cylindrical plates positioned opposite each other can also be joined together. Additionally, in this case, as... Figure 10C As shown, when the front end of the tube bites into the interior and contacts the tension resisting body 17, the arrangement of the wire 13 becomes disordered, and the tension resisting body 17 may break, which is therefore not preferred. Thus, even with an open cylindrical wire crimping section, although the wire 13 can be crimped from the entire circumference, it is preferable not to allow the tube to bite into contact with the tension resisting body 17.

[0110]

Example

[0111] Various types of wires with terminals were manufactured, and the electrical characteristics (resistance performance), mechanical characteristics (tensile strength performance), and corrosion resistance of the crimped joints were evaluated. Furthermore, as coated conductors, all were coated conductors with a tensile strength element disposed in the center of the cross-section and wire twisted around the outer periphery. For electrical characteristics, the resistance between the terminals and the coated conductors was measured for evaluation. For mechanical characteristics, the tensile strength was measured by pulling the coated conductor from the terminals and applying the load during the pull-out process. Corrosion resistance was evaluated using a salt spray test. The materials used are shown in Table 1, and the conditions and evaluation results are shown in Tables 2 to 10.

[0112] [Table 1]

[0113]

[0114] [Table 2]

[0115]

[0116] [Table 3]

[0117]

[0118] [Table 4]

[0119]

[0120] [Table 5]

[0121]

[0122] [Table 6]

[0123]

[0124] [Table 7]

[0125]

[0126] [Table 8]

[0127]

[0128] * Copper alloy wire: 0.51Fe - 0.11Ti - 0.13Mg - Remaining Cu and unavoidable impurities (wt%) [Table 9]

[0129]

[0130] [Table 10]

[0131]

[0132] The cross-sectional area of ​​an electrical wire is the total cross-sectional area of ​​the conductor. The conductor material is the material that makes up the conductor, and the tensile strength material is the material that makes up the tensile strength material. Furthermore, the term "fiber" in tensile strength material refers to multiple thin strands (fibers) bundled together, while "single wire" refers to a single thick tensile strength material.

[0133] Wire treatment refers to the treatment of the wire's termination; "tin plating" is, for example... Figure 4C The process of tin-plating each conductor as shown is called "plating together". Figure 4B The entire assembly is tin-plated as shown.

[0134] The "tube" in the shape of a terminal and Figure 1 Terminal 1 shown is also tubular in shape. Additionally, "open tube overlap" is... Figure 10A The shape shown is "interlaced open tubes". Figure 9A The shape shown is "open tube (no bite)". Figure 10B The shape shown is "open tube (with bite)". Figure 10C The shape shown.

[0135] Conductor compressibility refers to the total cross-sectional area of ​​the compressed conductor in the wire crimping section relative to the total cross-sectional area of ​​the conductor before compression. Additionally, tensile body compressibility is the apparent compressibility of a region of the tensile body; it refers to the cross-sectional area of ​​the region surrounded by the compressed conductor in the wire crimping section relative to the cross-sectional area of ​​the region surrounded by the uncompressed conductor.

[0136] The crimp resistance is the resistance between the front end of the terminal and the rear end of a 100mm long covered conductor. For crimp resistance, less than 1mΩ is designated "Excellent," 1mΩ to 2mΩ is designated "Good," and more than 2mΩ is designated "Poor." Tensile strength is the load when the covered conductor is pulled out of the terminal. For tensile strength, 50N or more is designated "Excellent," 40N or more but less than 50N is designated "Good," and less than 40N is designated "Poor." Regarding corrosion resistance, the conductor is sprayed with a 5mass salt solution at 35°C at 68.6–176.5 kPa for 96 hours, then left to stand at 80°C and 90–95% humidity for 96 hours. After drying at room temperature, it is confirmed whether it can be energized; those that can be energized are designated "Excellent."

[0137] As shown in Tables 2 to 8, for components where the tensile strength of the tensile body is higher than that of the conductor material and the tensile body is composed of multiple strands, the crimping resistance and tensile strength properties of all components with a conductor cross-sectional area of ​​0.05 sq to 0.35 sq are "good" or better. In particular, the crimping resistance of all components whose conductor material is not Cosun alloy wire is "very good". Furthermore, the tensile strength properties of all components whose tensile body is made of resin fiber other than carbon fiber are "very good".

[0138] On the other hand, Comparative Examples 1 and 3 did not have tensile strength and were subjected to medium to strong crimping, so the wire broke during crimping, and the tensile strength performance was "poor". In contrast, Comparative Example 2 was subjected to weak crimping, so the tensile strength performance was "very good", but the oxide film on the surface of the wire was not sufficiently destroyed, and the resistance performance of the crimped part was "poor".

[0139] In Comparative Examples 4 and 5, the tensile body is a single wire with almost no deformation on the outer surface. Therefore, the wire is excessively flattened and breaks during crimping, resulting in a "poor" resistance performance at the crimped joint. On the other hand, compared to Comparative Examples 4 and 5, Comparative Example 6 uses a weak crimp, thus suppressing wire flattening, resulting in a "good" resistance performance at the crimped joint. However, due to insufficient crimping, the tensile strength performance is "poor." Similarly, in Comparative Example 7, the tensile body is also a single wire with almost no deformation on the outer surface. Therefore, the resistance performance at the crimped joint is "poor," and due to electrolytic corrosion caused by the contact between dissimilar metals, copper and stainless steel wires, the corrosion resistance is "poor."

[0140] Furthermore, in Comparative Example 8, although the tensile body was made of resin fiber, its tensile strength was lower than that of the conductor material. Therefore, the tensile body was flattened during crimping, resulting in a "poor" tensile strength performance. In Comparative Example 9, the cylindrical piece in the conductor crimping portion bit into the tensile body, causing the conductors to become disordered. This resulted in a "poor" resistance performance at the crimping portion, and the tensile body was damaged, leading to a "poor" tensile strength performance as well.

[0141] The embodiments of the present invention have been described above with reference to the accompanying drawings, but the technical scope of the present invention is not affected by the above embodiments. Those skilled in the art will be able to conceive of various modifications or alterations within the scope of the technical concept described in the claims, and these naturally also fall within the technical scope of the present invention.

[0142] For example, the above description shows an example where a layer of wire 13 is arranged on the outer periphery of the tensile body 17, but the arrangement of the wire 13 is not limited to this. As long as the wire 13 is arranged on the outer periphery of the tensile body 17, it can be arranged as follows: Figure 11A As shown, two layers of conductors 13 are arranged around the tensile body 17, or as... Figure 11BAs shown, three layers of wires 13 are arranged around the tensile body 17. Furthermore, from the viewpoint of the conductivity and strength of the wires 13 themselves, the number of wires 13 is only required to be three or more in the layers connected to the tensile body 17, and preferably 20 or fewer. For example, as... Figures 4B to 4D , Figure 5 , Figure 11A , Figure 11B As shown, there can be 12 sticks, 14 sticks, 6 sticks, or 8 sticks, etc.

[0143] Furthermore, in the above description, an example of tensile body 17 being composed of multiple tensile body strands 17a was given. However, even if tensile body 17 is a single wire, its shape can deform along with the conductor 13 during compression, as long as a concave-convex shape is formed on the outer periphery after compression. For example, the tensile body of the aforementioned Comparative Examples 4 to 7 was a single wire, which was unacceptable. However, even if it is a single wire, if the outer surface deforms slightly during conductor compression, the decrease in the resistance performance of the crimped portion can be suppressed. However, if tensile body 17 is more easily deformed than conductor 13, it will not function as tensile body 17. Therefore, it is preferable that when conductor 13 is preferentially flattened and extends axially during compression, a slight concave-convex shape is formed on the surface of the tensile body under the pressure from conductor 13.

[0144] Label Explanation

[0145] 1, 1a: Terminal; 3: Terminal body; 4: Transition part; 5: Crimping part; 7: Wire crimping part; 9: Covered crimping part; 10, 10a: Wire with terminal; 11: Covered wire; 13: Wire; 15: Covering part; 17: Tensile body; 17a: Tensile body strand; 19: Terminal processing part; 21: Plating; 23: Gap.

Claims

1. A terminal-equipped wire, comprising a covered conductor and terminals electrically connected together, characterized in that, The covered conductor has a tensile strength body and a conductor disposed on the outer periphery of the tensile strength body and composed of a plurality of conductors. The cross-sectional area of ​​the conductor is less than 0.35 sq. The tensile strength of the tensile resisting body is higher than that of the conductor. The terminal has: A wire crimping portion that crimps the wire exposed from the front end of the covered wire; as well as A crimping portion that crimps the crimping portion of the crimped wire. The wire is crimped around its entire circumference in the wire crimping section. The outer peripheral surface of the tensile body has irregularities. The conductor deforms in a manner that enters the irregularities formed on the outer peripheral surface of the tensile body, thereby preventing the conductor from being excessively flattened and breaking.

2. The wire with terminals according to claim 1, characterized in that, The tensile body is composed of multiple strands of wire.

3. The terminal-equipped wire according to claim 1 or 2, characterized in that, The compression rate of the conductor is less than the compression rate of the area where the tensile body is disposed.

4. The terminal-equipped wire according to claim 1 or 2, characterized in that, The wire is twisted around the periphery of the tensile body.

5. The terminal-equipped wire according to claim 1 or 2, characterized in that, At least the front end of the conductor is compressed from the outer peripheral side.

6. The terminal-equipped wire according to claim 1 or 2, characterized in that, A plating process is performed on the conductor.

7. The terminal-equipped wire according to claim 1 or 2, characterized in that, The conductor is crimped around the entire circumference at a predetermined position in the axial direction by the conductor crimping portion.

8. The terminal-equipped wire according to claim 1 or 2, characterized in that, The wire crimping portion does not contact the tensile body.

9. The terminal-equipped wire according to claim 1 or 2, characterized in that, The cross-sectional area of ​​the conductor is less than 0.3 sq.

10. A wire harness, characterized in that, The harness is integrally formed of a plurality of terminal wires comprising the terminal wires as described in any one of claims 1 to 9.

11. A method for manufacturing a wire with terminals, wherein the wire with terminals is manufactured. The terminal-equipped wire is composed of a covered conductor and terminals electrically connected together. The covered conductor has a tensile strength body and a conductor disposed on the outer periphery of the tensile strength body and composed of a plurality of conductors. The cross-sectional area of ​​the conductor is less than 0.35 sq. The tensile strength of the tensile resisting body is higher than that of the conductor. The terminal has: A wire crimping portion that crimps the wire exposed from the front end of the covered wire; and A crimping portion that crimps the crimping portion of the crimped wire. The wire is crimped around its entire circumference in the wire crimping section. The outer peripheral surface of the tensile body has irregularities. The conductor deforms in a manner that enters the unevenness formed on the outer peripheral surface of the tensile body, thereby preventing the conductor from being excessively flattened and breaking. Its features are, When the wire crimping portion is crimped, in the initial stage of compression, both the compression ratio of the wire and the apparent compression ratio of the tensile body decrease. Afterward, as compression continues, the decrease in the apparent compression ratio of the tensile body becomes relatively smaller, and the main reduction is in the compression ratio of the wire.

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