Electrical wire with terminals

Abstract

To provide an electric wire with a terminal, capable of reducing an increase in electrical resistance between a conductor and a terminal even in a high temperature environment.SOLUTION: An electric wire with a terminal includes: an assembled twisted conductor comprising a plurality of conductors; an inclusion tape wound around an outer peripheral surface of the assembled twisted conductor at an end of the assembled twisted conductor; and a terminal caulked and attached to the end of the assembled twisted conductor through the inclusion tape. The plurality of conductors each comprise a conductor containing aluminum. The terminal includes: a body part comprising copper or a copper alloy; and a tin plating layer formed on a surface of the body part. The inclusion tape contains copper.SELECTED DRAWING: Figure 4

Description

[[Technical Field]]

[0001] The present disclosure relates to an electric wire with a terminal. [[Background Art]]

[0002] Patent Document 1 discloses an electric wire with a terminal. An electric wire with a terminal is manufactured by crimping a terminal to an end portion of an electric wire. As a conductor included in the electric wire, a conductor made of aluminum or an aluminum alloy is described. As the terminal, a terminal made of copper or a copper alloy is described. [[Prior Art Document]] [[Patent Document]]

[0003] [[Patent Document 1]] Japanese Unexamined Patent Application Publication No. 2010-108828 [[Summary of the Invention]] [[Problem to be Solved by the Invention]]

[0004] As a terminal, a tin-plated copper terminal is known. A tin-plated copper terminal includes a main body portion made of copper or a copper alloy, and a tin plating layer formed on a surface of the main body portion. When a conductor included in an electric wire is made of aluminum and the terminal is a tin-plated copper terminal, the conductor is easily oxidized in a high-temperature environment, and as a result, the electrical resistance between the conductor and the terminal tends to easily increase.

[0005] In one aspect of the present disclosure, it is preferable to provide an electric wire with a terminal that can reduce an increase in electrical resistance between the conductor and the terminal even in a high-temperature environment. [[Means for Solving the Problem]]

[0006] One aspect of the present disclosure includes: an aggregated twisted conductor composed of a plurality of conductors; an interposition tape wound around an outer peripheral surface of the aggregated twisted conductor at an end portion of the aggregated twisted conductor; and a terminal attached by crimping to the end portion of the aggregated twisted conductor via the interposition tape.

[0007] The plurality of conductors are composed of conductors containing aluminum. The terminal includes a body made of copper or a copper alloy and a tin-plated layer formed on the surface of the body. The intervening tape contains copper. One aspect of this disclosure, a wire with a terminal, can reduce the increase in electrical resistance between the conductor and the terminal even in high-temperature environments. [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view showing the configuration of a wire with terminals. [Figure 2] This is a side view showing the configuration of a wire with terminals. [Figure 3] This is a cross-sectional view taken along section III-III in Figure 1. [Figure 4] This is a cross-sectional view taken at section IV-IV in Figure 1. [Figure 5] This is an explanatory diagram showing the shape and position of the rod at the end of an electric wire. [Figure 6] This is an explanatory diagram illustrating the behavior of a terminal-equipped electric wire during a heat cycle, as shown in the example. [Figure 7] This is an explanatory diagram illustrating the behavior of the terminal-equipped electric wire during a heat cycle in the present disclosure. [Figure 8] This is a cross-sectional view showing the cross-section of the terminal-equipped wire in Example 1. [Figure 9] This graph shows the measurement results of the resistance ratio Y2 after heat cycling in Example 1. [Figure 10] This graph shows the measurement results of the resistance ratio change Z in Example 1. [Figure 11] This is a cross-sectional view showing the layer structure of an intervening tape comprising a main layer made of copper and Sn-plated layers formed on both sides of the main layer. [Modes for carrying out the invention]

[0009] Exemplary embodiments of this disclosure will be described with reference to the drawings. 1. Configuration of terminal-equipped wire 1 The configuration of the terminal-equipped wire 1 will be explained based on Figures 1 to 5. As shown in Figures 1 and 2, the terminal-equipped wire 1 comprises a wire 3 and a terminal 5. In Figures 1 and 2, terminals 5 are attached to both ends 3A of the wire 3, but terminals 5 may be attached to only one end 3A of the wire 3.

[0010] Figure 3 is a cross-sectional view of the electric wire 3. The cross-section shown in Figure 3 is perpendicular to the longitudinal direction L of the electric wire 3 and the stranded conductor 7 (described later), and does not pass through the end portion 3A. As shown in Figure 3, the electric wire 3 comprises a stranded conductor 7 and an insulating layer 9. In the cross-section perpendicular to the longitudinal direction L, the shape of the stranded conductor 7 is, for example, circular. The diameter of the stranded conductor 7 is preferably 7 mm or more and 25 mm or less. However, the portion of the stranded conductor 7 that is crimped together with the electric wire connection portion 31 (described later) is deformed.

[0011] The stranded conductor 7 consists of multiple conductors 21. The multiple conductors 21 are twisted together. The direction in which the multiple conductors 21 are twisted together may be clockwise or counterclockwise.

[0012] Each of the multiple conductors 21 is a linear member extending along the longitudinal direction L. In a cross-section perpendicular to the longitudinal direction L, the shape of each conductor 21 is, for example, circular. The diameter of the conductor 21 is preferably 1 mm or more and 5 mm or less.

[0013] The conductor 21 may be a single wire or a combination of multiple wires twisted together. For example, a plating layer may be formed on the surface of the wires. In this case, corrosion of the wires can be suppressed. The direction in which the multiple wires are twisted together may be clockwise or counterclockwise. The direction in which the multiple wires are twisted together may be the same as or different from the direction in which the multiple conductors 21 are twisted together.

[0014] The plurality of conductors 21 are composed of conductors 21 containing aluminum. That is, any conductor 21 included in the plurality of conductors 21 is a conductor 21 containing aluminum. The conductor 21 containing aluminum is, for example, a conductor 21 made of aluminum or a conductor 21 made of an aluminum alloy.

[0015] The conductor 21 is, for example, provided with a plating layer on a surface thereof. The plating layer exhibits a function of suppressing corrosion, for example. The plating layer is, for example, a tin plating layer. For example, as shown in FIG. 3, the collective twisted conductor 7 includes two or more layers each formed by arranging a plurality of conductors 21 in the circumferential direction. Note that the circumferential direction refers to a circumferential direction centered on the center of the electric wire 3 in a cross section orthogonal to the longitudinal direction L.

[0016] For example, the collective twisted conductor 7 includes a conductor 21A positioned at the center of the collective twisted conductor 7, a layer formed by arranging conductors 21B in the circumferential direction, a layer formed by arranging conductors 21C in the circumferential direction, and a layer formed by arranging conductors 21D in the circumferential direction, excluding a portion where a rod material 11 described later is inserted. Note that the conductors 21A, 21B, 21C, and 21D are one form of the conductor 21.

[0017] The layer formed by arranging the conductors 21B in the circumferential direction is provided on the outer peripheral side of the conductor 21A. Note that the outer peripheral side refers to an outer peripheral side centered on the center of the electric wire 3 in a cross section orthogonal to the longitudinal direction L. The number of conductors 21B arranged in the circumferential direction is, for example, six.

[0018] The layer formed by arranging the conductors 21C in the circumferential direction is provided on the outer peripheral side of the layer formed by arranging the conductors 21B in the circumferential direction. The number of conductors 21C arranged in the circumferential direction is, for example, twelve.

[0019] The layer formed by arranging the conductors 21D in the circumferential direction is provided on the outer peripheral side of the layer formed by arranging the conductors 21C in the circumferential direction. The number of conductors 21D arranged in the circumferential direction is, for example, eighteen.

[0020] As shown in Figure 3, the insulating layer 9 covers the stranded conductor 7. However, as shown in Figures 1 and 2, at end 3A, the stranded conductor 7 is not covered by the insulating layer 9 and is exposed. Examples of materials for the insulating layer 9 include resin and rubber. The electric wire 3 may further include a shielding layer or the like.

[0021] As shown in Figures 1 and 2, the terminal 5 is electrically connected to the electric wire 3 at its end 3A. As shown in Figure 4, the terminal 5 comprises a main body 5A made of copper or a copper alloy and a tin plating layer 5B. The tin plating layer 5B is formed on the surface of the main body 5A. The thickness of the tin plating layer 5B is, for example, 0.1 μm to 2 μm. The tin plating layer 5B has a function of suppressing corrosion, for example.

[0022] As shown in Figures 1 and 2, the main body of the terminal 5 comprises a wire connection portion 31 and a mating connection portion 33. The terminal 5 is, for example, a ring crimp terminal. When the terminal 5 is a ring crimp terminal, the wire connection portion 31 is a hollow cylindrical part. The mating connection portion 33 is, for example, a flat plate-shaped part. In accordance with JIS C2805:2010 (Crimping terminals for copper wires), a terminal 5 having an inner diameter of the wire connection portion 31 suitable for the cross-sectional area of ​​the stranded conductor 7 can be selected.

[0023] End portion 3A is inserted into the wire connection portion 31. With end portion 3A inserted into the wire connection portion 31, the wire connection portion 31 is crimped. As a result, terminal 5 is fixed to wire 3. A commercially available crimping jig or compression jig can be used for crimping.

[0024] The terminal-equipped wire 1 includes a rod 11, as shown in Figures 4 and 5. A plating layer is formed on the inner and outer surfaces of the wire connection portion 31. Figure 4 shows a cross-section perpendicular to the longitudinal direction L, passing through the end portion 3A and the wire connection portion 31. The rod 11 is inserted into the twisted conductor 7 at the end portion 3A. The rod 11 is inserted between the conductors 21. The rod 11 extends along the longitudinal direction L. That is, the longitudinal direction of the rod 11 coincides with or approximates the longitudinal direction L.

[0025] As shown in Figure 4, in a cross-section perpendicular to the longitudinal direction L, the rod 11 is preferably surrounded by the conductor 21, and more preferably located near the center of the stranded conductor 7.

[0026] In a cross-section perpendicular to the longitudinal direction L, if the rod 11 is located near the center of the stranded conductor 7, for example, one conductor 21A and six conductors 21B surround the rod 11. Figure 4 shows the state before the wire connection 31 is crimped. After the wire connection 31 is crimped, the wire connection 31 and the stranded conductor 7 are deformed, as shown in Figure 7.

[0027] As shown in Figure 5, in the longitudinal direction L, the area where the rod 11 is located preferably includes at least a portion of the area where the wire connection portion 31 is located, and more preferably includes the entire area where the wire connection portion 31 is located. In the longitudinal direction L, it is preferable that the rod 11 does not protrude from the area where the wire connection portion 31 is located. In this case, even when the wire 3 is bent near the end portion 3A, damage to the stranded conductor 7 by the rod 11 can be suppressed.

[0028] The coefficient of thermal expansion of the rod 11 is preferably smaller than the coefficient of thermal expansion of the wire connection part 31. The coefficient of thermal expansion of the rod 11 is preferably smaller than the coefficient of thermal expansion of copper. The material of the rod 11 is preferably iron, steel, stainless steel, nickel steel, titanium, or Invar. The coefficient of thermal expansion of these materials is preferably smaller than the coefficient of thermal expansion of copper (17.7 × 10⁻⁶). -6 Smaller than / ℃

[0029] A plating layer may be formed on the surface of the rod 11. When a plating layer is formed, corrosion of the rod 11 can be suppressed. The rod 11 may be a single wire or a plurality of linear members twisted together. Examples of the shape of the rod 11 in a cross section perpendicular to the longitudinal direction L include circular, elliptical, and other shapes. The shape of the tip of the rod 11 may be tapered to facilitate insertion into the twisted conductor 7. Preferable plating layers formed on the surface of the rod 11 include zinc plating, nickel plating, and chromium plating. Zinc plating is preferably chromate-treated.

[0030] As shown in Figure 4, the terminal-equipped wire 1 further comprises an intervening tape 41. The intervening tape 41 is wound around the outer surface of the stranded conductor 7 in an area that includes at least a portion of the end 3A. The intervening tape 41 is located between the tin-plated layer 5B of the terminal 5 and the stranded conductor 7 in the radial direction of the wire 3. Therefore, the wire connection portion 31 of the terminal 5 is crimped and attached to the end 3A of the stranded conductor 7 via the intervening tape 41. In the longitudinal direction L, the area over which the intervening tape 41 is wound may be the entire portion facing the wire connection portion 31, or it may be only a portion of that portion. In the circumferential direction of the stranded conductor 7, the area over which the intervening tape 41 is wound may be the entire circumference of the outer surface, or it may be only a portion of the outer surface.

[0031] The intervening tape 41 is a tape made of a material containing copper. The intervening tape 41 has, for example, a plating layer on its surface. For example, the intervening tape 41 has the configuration shown in Figure 11. Figure 11 is a cross-sectional view of the intervening tape 41 perpendicular to the main surface. The intervening tape 41 comprises a main layer 41A made of copper and Sn plating layers 41B and 41C. The Sn plating layer 41B is formed on one surface of the main layer 41A. The Sn plating layer 41C is formed on the surface of the main layer 41A opposite to the surface on which the Sn plating layer 41B is formed.

[0032] The plating layer is formed on both sides of the intervening tape 41. Examples of the plating layer include a tin plating layer. When a tin plating layer is formed, the copper contained in the intervening tape 41 diffuses into the plating layer, so that at least a portion of the composition of the plating layer becomes a SnCu compound.

[0033] The thickness of the intervening tape 41 is preferably 5 μm or more and 50 μm or less. The thickness of the plating layer is preferably 0.1 μm or more and 2 μm or less.

[0034] If the intervening tape 41 has a plating layer, corrosion of the terminals 5 and the stranded conductors 7 can be suppressed.

[0035] The winding method of the intervening tape 41 is not particularly limited. Examples of winding methods for the intervening tape 41 include wrap winding and longitudinal winding. Furthermore, the winding direction of wrap winding may be the same as or opposite to the main twisting direction of the bundled twisted conductor 7. 2. Manufacturing method of terminal-equipped electric wire 1 The terminal-equipped wire 1 can be manufactured, for example, by the following method.

[0036] (1) Prepare the electric wire 3. At this point, the stranded conductor 7 is covered with an insulating layer 9, even at its end 3A. Also, at this point, the rod 11 is not inserted into the inside of the stranded conductor 7.

[0037] (2) Insert the rod 11 into the twisted conductor 7 from the end face 3B of the twisted conductor 7 shown in Figures 1, 2, and 5. The insertion direction is parallel to the longitudinal direction L. The end face 3B is the surface of the twisted conductor 7 at the tip in the longitudinal direction L.

[0038] (3) Remove the insulating layer 9 at end 3A. The length of the insulating layer 9 to be removed is the same length as or longer than the length of the wire connection part 31. (4) At end 3A, an intervening tape 41 is wrapped around the outer surface of the stranded conductor 7. (5) Insert the end portion 3A into the wire connection portion 31 and crimp the wire connection portion 31. Alternatively, (2) may be performed after (3). However, performing (2) first is preferable because when (2) is performed, the multiple conductors 21 are held by the insulating layer 9 and the multiple conductors 21 are less likely to spread outwards. If the terminal wire 1 does not have a rod 11, (2) can be omitted.

[0039] 3. Effects of the terminal-equipped wire 1 (3A) When the conductor 21 constituting the stranded conductor 7 is an aluminum-containing conductor 21, and the terminal 5 is a tin-plated copper terminal, the conductor 21 is prone to oxidation in high-temperature environments, and the electrical resistance between the terminal 5 of the terminal-equipped wire 1 and the wire 3 tends to increase. The intervening tape 41 can suppress the oxidation of the conductor 21 even in high-temperature environments and reduce the increase in electrical resistance between the terminal 5 of the terminal-equipped wire 1 and the wire 3.

[0040] (3B) When the terminal-equipped wire 1 is equipped with a rod 11, the terminal-equipped wire 1 can reduce the increase in electrical resistance between the terminal 5 and the wire 3 even when placed in an environment with drastic temperature changes. The reason for this is presumed to be as follows. Figure 6 shows a cross-section of a reference example of a terminal-equipped wire during a heat cycle. The cross-section shown in Figure 6 is perpendicular to the longitudinal direction L and passes through the wire connection portion 31. The reference example terminal-equipped wire differs from the terminal-equipped wire 1 shown in Figures 1 to 5 in that it does not have a rod 11, but is otherwise identical. In the reference example terminal-equipped wire, a bundled stranded conductor 7 is present inside the wire connection portion 31. The wire connection portion 31 and the bundled stranded conductor 7 are deformed due to the crimping of the wire connection portion 31. Note that the intervening tape 41 and the tin-plated layer 5B are omitted from Figure 6 and Figure 7, which will be described later.

[0041] State A in Figure 6 represents the terminal-equipped wire of the reference example at room temperature. Room temperature is 25°C. State B in Figure 6 represents the terminal-equipped wire of the reference example after being heated to a high temperature following state A. High temperature is 125°C. Since the coefficient of linear expansion of the bundled stranded conductor 7 is greater than that of the wire connection portion 31, in state B, the bundled stranded conductor 7 tends to expand significantly outward beyond the wire connection portion 31. If the wire connection portion 31 were not present, the bundled stranded conductor 7 would expand to the virtual wire 101, but because the wire connection portion 31 is actually present, it is difficult for it to expand. Therefore, in state B, the bundled stranded conductor 7 undergoes plastic deformation to extend in the longitudinal direction L, and the amount of bundled stranded conductor 7 in the cross-section shown in Figure 6 decreases.

[0042] State C in Figure 6 represents the state after state B, when the terminal-equipped wire of the reference example is brought to room temperature. In state B, the amount of bundled stranded conductor 7 in the cross-section shown in Figure 6 is reduced, so in state C, the bundled stranded conductor 7 shrinks significantly. On the other hand, in state C, the wire connection part 31 shrinks less than the bundled stranded conductor 7. As a result, a gap 103 is created between the bundled stranded conductor 7 and the wire connection part 31, and the electrical resistance between the terminal 5 and the wire 3 increases.

[0043] Figure 7 shows a cross-section of the terminal-equipped wire 1 in the configuration shown in Figures 1 to 5 during a heat cycle. The cross-section shown in Figure 7 is perpendicular to the longitudinal direction L and passes through the wire connection portion 31. In the terminal-equipped wire 1, a bundled stranded conductor 7 exists inside the wire connection portion 31. Due to the crimping of the wire connection portion 31, the wire connection portion 31 and the bundled stranded conductor 7 are deformed. A rod 11 exists inside the bundled stranded conductor 7.

[0044] State A in Figure 7 represents the state where the terminal-equipped wire 1 is at room temperature. State B in Figure 7 represents the state after the terminal-equipped wire 1 has been heated to a high temperature after state A. Because the terminal-equipped wire 1 is equipped with a rod material 11 with a small coefficient of linear expansion, in state B, the bundled stranded conductor 7 is less likely to expand compared to the terminal-equipped wire of the reference example. Because the bundled stranded conductor 7 is less likely to expand, in state B, the bundled stranded conductor 7 is less likely to undergo plastic deformation, and the amount of bundled stranded conductor 7 in the cross-section shown in Figure 7 is less likely to decrease.

[0045] State C in Figure 7 represents the state after state B, when the terminal-attached wire 1 has been brought to room temperature. In state B, the amount of bundled stranded conductor 7 in the cross-section shown in Figure 7 does not decrease easily, so even in state C, the bundled stranded conductor 7 does not shrink easily. As a result, a gap 103 is unlikely to occur between the bundled stranded conductor 7 and the wire connection part 31, and the increase in electrical resistance between the terminal 5 and the wire 3 can be reduced.

[0046] (3C) The material of the bar stock 11 is, for example, iron, steel, stainless steel, nickel steel, titanium, or Invar. These materials have a small coefficient of thermal expansion. Therefore, when the material of the bar stock 11 is iron, steel, stainless steel, nickel steel, titanium, or Invar, the effect of (3B) is even greater.

[0047] 4. Example 1 (1) Manufacturing of terminal-equipped electric wire 1A A terminal-equipped wire 1A was manufactured. In terminal-equipped wire 1A, as shown in Figure 8, the bundled stranded conductor 7 consisted of one conductor 21A, six conductors 21B, and twelve conductors 21C, and did not include a conductor 21D. Conductors 21A, 21B, and 21C each consisted of 34 strands of 0.45 mm diameter aluminum wire twisted together. Conductors 21A, 21B, and 21C correspond to conductor 21 which contains aluminum.

[0048] In the stranded conductor 7, the conductor 21A was located at the center of the stranded conductor 7, except for the portion where the rod 11 was inserted. A layer consisting of six conductors 21B arranged circumferentially was located on the outer periphery of the conductor 21A. A layer consisting of twelve conductors 21C arranged circumferentially was located further out on the outer periphery of that layer. The diameter of the stranded conductor 7 was 15 mm.

[0049] Furthermore, the terminal-equipped wire 1A was equipped with an intervening tape 41. The intervening tape 41 was wound around the entire outer circumference of the stranded conductor 7 at end 3A. In the longitudinal direction L, the area over which the intervening tape 41 was wound was the entire portion of end 3A facing the wire connection portion 31. In the radial direction of the wire 3, the intervening tape 41 was located between the tin-plated layer 5B of the terminal 5 and the stranded conductor 7.

[0050] As shown in Figure 11, the intervening tape 41 comprised a main layer 41A made of copper and Sn plating layers 41B and 41C. The Sn plating layer 41B was formed on one surface of the main layer 41A. The Sn plating layer 41C was formed on the surface of the main layer 41A opposite to the surface on which the Sn plating layer 41B was formed. The composition of the Sn plating layers 41B and 41C was a SnCu compound. The thickness of the main body layer 41A, which was made of copper, was 35 μm. The thickness of the Sn plating layers 41B and 41C was 0.7 μm, each.

[0051] The terminal-equipped wire 1A had a rod 11. The rod 11 was located near the center of the stranded conductor 7 in a cross section perpendicular to the longitudinal direction L. One conductor 21A and six conductors 21B surrounded the rod 11. The material of the rod 11 was mild steel. Mild steel is low-carbon steel conforming to JIS G 3505:2017. In a cross section perpendicular to the longitudinal direction L, the shape of the rod 11 was circular. The diameter of the rod 11 was 3 mm. Even in the portion where the rod 11 was inserted, the diameter of the stranded conductor 7 was 15 mm. The length of the rod 11 in the longitudinal direction L was 30 mm.

[0052] As shown in Figure 5, one end of the rod 11 was on the end face 3B. Also, in the longitudinal direction L, the area where the rod 11 was located encompassed the entire area where the wire connection portion 31 was located.

[0053] The terminal 5 comprised a main body 5A made of copper and a tin-plated layer 5B. The tin-plated layer 5B was formed on the surface of the main body 5A. The tin-plated layer 5B consisted of a lower layer made of SnCu alloy and an upper layer made of Sn. The thickness of the tin-plated layer 5B was 8 μm.

[0054] (2) Manufacturing of wires RA with terminals We manufactured a terminal-equipped wire RA that basically had the same configuration as terminal-equipped wire 1A. However, although terminal-equipped wire RA had a rod 11, it did not have an intervening tape 41. (3) Manufacturing of terminal-equipped electric wire RB We manufactured a terminal-equipped wire RB that basically had the same configuration as terminal-equipped wire 1A. However, terminal-equipped wire RB did not have a rod 11 and an intervening tape 41. (4) Evaluation of terminal-equipped wires 1A, RA, RB The terminal-equipped wires 1A, RA, and RB were evaluated using the following procedure. First, Rt and Rc were measured. Rt is the electrical resistance between point P1 on wire 3 and point P2 on the mating connection part 33, as shown in Figure 1. Point P1 is a point on wire 3 and is a point on the stranded conductor 7. The electrical connection path between point P1 and point P2 includes the connection part between wire 3 and terminal 5. Rc is the electrical resistance between point P1 and point P3 on wire 3. The distance between point P1 and point P2 is equal to the distance between point P1 and point P3.

[0055] Next, the resistance ratio Y (%) was calculated by substituting Rt and Rc into the following equation (1). Equation (1) Y = (Rt / Rc) × 100 Next, terminal-equipped wires 1A, RA, and RB were placed in an environment where a predetermined number of heat cycles were repeated. Each heat cycle involved raising the temperature to 125°C, holding it at 125°C for 1 hour, cooling it to -40°C, and holding it at -40°C for 1 hour.

[0056] After repeating the heat cycle a predetermined number of times, the resistance ratio Y was calculated again. The resistance ratio Y calculated before the heat cycle is defined as the initial resistance ratio Y1 (%). The resistance ratio Y calculated after the heat cycle is defined as the post-heat cycle resistance ratio Y2 (%). The resistance ratio change Z (%), expressed by the following equation (2), was calculated.

[0057] Equation (2) Z = Y² - Y¹ Figure 9 shows the post-heat cycle resistance ratio Y2 for terminal-equipped wires 1A, RA, and RB when the number of heat cycles is 10, 20, and 50. Figure 10 shows the change in resistance ratio Z when the number of heat cycles is 10, 20, and 50. In Figures 9 and 10, "Number of Cycles" on the horizontal axis represents the number of heat cycles. The post-heat cycle resistance ratio Y2 and the change in resistance ratio Z for terminal-equipped wire 1A were significantly smaller than those for terminal-equipped wires RA and RB. The heat cycle resistance ratio Y2 and resistance ratio change Z in terminal-equipped wire RA were significantly smaller than those in terminal-equipped wire RB. Therefore, it was found that applying either the rod 11 or the intervening tape 41 to terminal-equipped wire 1 can reduce the heat cycle resistance ratio Y2 and resistance ratio change. Furthermore, it was found that applying both the rod 11 and the intervening tape 41 to terminal-equipped wire 1 can further reduce the heat cycle resistance ratio Y2 and resistance ratio change.

[0058] For each of the terminal-equipped wires 1A, RA, and RB, two samples were prepared and evaluated. The two samples of terminal-equipped wire 1A are denoted as 1A_1 and 1A_2. The two samples of terminal-equipped wire RA are denoted as RA_1 and RA_2. The two samples of terminal-equipped wire RB are denoted as RB_1 and RB_2.

[0059] 7. Other Embodiments Although embodiments of the present disclosure have been described above, the present disclosure is not limited to the embodiments described above and can be implemented in various modified forms.

[0060] (1) In the stranded conductor 7, the number of layers in which the multiple conductors 21 are arranged in the circumferential direction may be other than 3 layers, for example, 2 layers, 4 layers, 5 layers, 6 layers, etc. (2) In a cross section perpendicular to the longitudinal direction L, the multiple conductors 21 do not have to be arranged in the circumferential direction. For example, in a cross section perpendicular to the longitudinal direction L, the multiple conductors 21 may be arranged randomly.

[0061] (3) In a cross section perpendicular to the longitudinal direction L, the rod 11 may be located off-center from the center of the stranded conductor 7. In this case as well, it is preferable that the rod 11 is surrounded by the conductor 21. (4) The terminal-equipped wire 1 does not need to be equipped with a rod 11. Even if the rod 11 is not equipped, the terminal-equipped wire 1 can achieve the effect of (3A) above by the intervening tape 41.

[0062] (5) The function of one component in each of the above embodiments may be divided among multiple components, or the function of multiple components may be performed by one component. Also, some of the configurations of each of the above embodiments may be omitted. Also, at least some of the configurations of each of the above embodiments may be added to, replaced with, etc., the configurations of other embodiments.

[0063] (6) In addition to the terminal-equipped wire 1 described above, this disclosure can also be realized in various forms, such as a system that uses the terminal-equipped wire 1 as a component, a method for manufacturing the terminal-equipped wire 1, etc. [Explanation of Symbols]

[0064] 1...Wire with terminal, 3...Wire, 3A...End, 3B...End face, 5...Terminal, 5A...Main body, 5B...Tin plating layer, 7...Twisted conductor, 9...Insulating layer, 11...Rod, 21, 21A, 21B, 21C, 21D...Conductor, 31...Wire connection part, 33...Mating connection part, 41...Interfacing tape, 101...Imaginary line, 103...Gap

Claims

1. A stranded conductor consisting of multiple conductors, At the end of the aforementioned stranded conductor, an intervening tape is wrapped around the outer surface of the stranded conductor, A terminal crimped to the end of the stranded conductor via the intervening tape, Equipped with, The plurality of conductors are composed of conductors containing aluminum, The terminal includes a main body made of copper or a copper alloy and a first tin plating layer formed on the inner surface of the main body. The intervening tape comprises a main body layer made of copper and a second tin plating layer formed on each of the two sides of the main body layer. The aforementioned first tin plating layer is composed of a lower layer made of a SnCu alloy and an upper layer made of Sn. The aforementioned second tin plating layer is composed of a SnCu compound. Electrical wire with terminals.

2. A wire with terminals as described in claim 1, The device further comprises a rod inserted into the twisted conductor at the end and extending along the longitudinal direction of the twisted conductor, The coefficient of linear thermal expansion of the aforementioned rod is smaller than that of copper. The tip of the aforementioned rod is tapered. Electrical wire with terminals.

3. A wire with terminals as described in claim 2, The aforementioned rod material is an electric wire with terminals, made of iron, steel, stainless steel, nickel steel, titanium, or Invar.

4. A wire with terminals as described in Claim 3, The surface of the aforementioned rod material is formed with a zinc plating layer, a nickel plating layer, or a chromium plating layer. Electrical wire with terminals.

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