JP2009193889A - Terminal fitting and wire harness - Google Patents

Abstract

The present invention provides a terminal fitting and a wire harness that improve the contact resistance with an electric wire and suppress a decrease in mechanical strength.
A female terminal fitting (12) having a wire barrel (16) caulked from the outside to a terminal of an electric wire (11) and a connecting portion (17) connected to the male terminal fitting connected to the wire barrel (16). Of these, a recess group consisting of a plurality of recesses 18 extending in a direction intersecting the axial direction of the electric wire 11 and spaced in the axial direction of the electric wire 11 is formed on the surface on the electric wire 11 side. A plurality of sets are formed side by side in the direction crossing the axial direction of the electric wire 11.
[Selection] Figure 2

Description

  The present invention relates to a terminal fitting and a wire harness.

  2. Description of the Related Art Conventionally, as a terminal fitting connected to an end of an electric wire, for example, the one described in Patent Document 1 is known. The terminal fitting is made of a metal plate material, and includes a crimping portion that is caulked from the outside to a wire core exposed from the end of the electric wire, and a connection portion that is connected to the mating terminal connected to the crimping portion.

  When an oxide film is formed on the surface of the above-described wire core, there is a concern that the contact resistance between the wire core and the crimping portion may increase due to the oxide film interposed between the wire core and the crimping portion. The

  Therefore, in the prior art, a concave portion (serration) continuously extending in a direction intersecting the axial direction of the electric wire is formed on the inner side (wire core side) of the crimping portion. A plurality of the recesses are formed side by side in the axial direction of the electric wire.

When the crimping portion is caulked to the wire core of the electric wire, the wire core is pressed by the crimping portion and extends in the axial direction. Then, the oxide film formed on the surface of the wire core is peeled off by being in sliding contact with the opening edge of the recess. Then, the new surface of the wire core comes into contact with the crimping portion. Thereby, the contact resistance between an electric wire and a terminal metal fitting can be made small.
JP-A-10-125362

  In recent years, the use of aluminum or an aluminum alloy as a material for the wire core has been studied. An oxide film is relatively easily formed on the surface of the aluminum or aluminum alloy. For this reason, for example, when aluminum or an aluminum alloy is used for the wire core of the electric wire, the contact resistance between the wire core and the crimping portion may not be sufficiently reduced even when the recess is formed. .

  Therefore, it is conceivable to increase the compression rate of the crimping part. As a result, the oxide film formed on the wire core is sufficiently peeled off, and the opening edge of the recess bites into the wire core, so that it is expected that the contact resistance between the wire core and the crimping portion can be reduced. .

  However, when the compression rate of the crimping part is increased as described above, the crimping part is greatly plastically deformed in the axial direction of the electric wire. Then, we are anxious about the mechanical strength in a recessed part with a comparatively small board thickness falling among crimping | compression-bonding parts.

  This invention was completed based on the above situations, and improved the contact resistance between electric wires, and the terminal metal fitting which suppressed the fall of mechanical strength, and the wire harness provided with this terminal metal fitting The purpose is to provide.

  The present invention provides a terminal fitting having a crimping portion caulked from the outside exposed to the conductor exposed from the end of the electric wire including the conductor, and a connection portion connected to the mating terminal fitting connected to the crimping portion, or this A wire harness including a terminal fitting, wherein a plurality of the crimping portions on a surface on the electric wire side extend in a direction intersecting an axial direction of the electric wire and are arranged at intervals in the axial direction of the electric wire. A recess group consisting of recesses is formed, and a plurality of the recess groups are formed in a row in the direction intersecting the axial direction of the electric wire.

  When the crimping portion is caulked to the electric wire, the electric wire is pressed by the crimping portion and extends in the axial direction. According to the present invention, a relatively large stress is concentrated on the electric wire in the region between the concave portions constituting the concave group. Then, in the opening edge located between each recessed part, the oxide film formed in the surface of an electric wire peels, and the new surface of an electric wire is exposed. The contact resistance between the electric wire and the terminal fitting can be reduced by contacting the new surface of the electric wire and the crimping portion.

  Furthermore, the deformation of the electric wire is promoted by the concentration of relatively large stress on the electric wire. Thereby, since the opening edge located between each recessed part bites into an electric wire, the contact resistance of an electric wire and a terminal metal fitting can be made still smaller.

  Further, when the crimping portion is caulked to the electric wire, the crimping portion is also plastically deformed in the axial direction of the electric wire. In view of this point, in the present invention, a plurality of sets of the recess groups are formed side by side in the circumferential direction of the electric wire with a space therebetween. Thereby, the area | region where a recessed part does not exist is formed between recessed part groups. Since the region in which the concave portion group does not exist absorbs the force that plastically deforms the crimp portion in the axial direction of the electric wire, the concave portion is prevented from being greatly plastically deformed in the axial direction of the electric wire. As a result, the mechanical strength of the terminal fitting can be maintained.

  The following configuration is preferable as an embodiment of the present invention.

  The space | interval of each said recessed part about the axial direction of the said electric wire in each said recessed part group may be set to 1-4 times the depth dimension of the said recessed part.

  If the distance between the recesses in the axial direction of the electric wire is smaller than the depth dimension of the recesses, it is not preferable because it becomes difficult to process the recesses. On the other hand, if the interval between the recesses exceeds 4 times the depth of the recesses, it is not preferable because it cannot be distinguished from normal serrations.

  The recess group may be formed in a plurality of rows at intervals in the axial direction of the electric wire.

  With the above configuration, the contact area between the electric wire and the terminal fitting can be increased as compared with the case where the recess group is formed in only one row. Thereby, the contact resistance between an electric wire and a terminal metal fitting can be made still smaller.

  The recess groups adjacent to each other in the axial direction of the electric wire may be arranged at positions shifted from each other in the axial direction of the electric wire.

  In the region where no recess group is formed in the circumferential direction of the electric wire, the electric wire and the opening edge of each recess do not slide. Then, we are anxious about the contact resistance between an electric wire and a terminal metal fitting becoming non-uniform | heterogenous.

  In view of the above points, in this configuration, the recess group is arranged at a position shifted from each other in the axial direction of the electric wire. Thereby, each recessed part group can be distributed and arranged about the axial direction of an electric wire. Then, since an electric wire and each recessed part are slidably contacted on the average with respect to the axial direction of an electric wire, the contact resistance between an electric wire and a terminal metal fitting can be equalized.

  The recess group may include a pair of recesses.

  The said electric wire is good also as a structure provided with the wire core which consists of aluminum or aluminum alloy, and the insulation coating which surrounds the outer periphery of the said wire core.

  When the wire core is made of aluminum or an aluminum alloy, in order to break the oxide film formed on the surface of the wire core and reduce the contact resistance, it is necessary to crimp the crimping portion to the wire core with a high compression rate. In such a case, this configuration is effective.

  ADVANTAGE OF THE INVENTION According to this invention, while reducing the contact resistance between an electric wire and a terminal metal fitting, the fall of the mechanical strength of a terminal metal fitting can be suppressed.

<Embodiment 1>
Embodiment 1 of the present invention will be described with reference to FIGS. The wire harness 10 according to the present embodiment includes an electric wire 11 and a female terminal fitting 12 (corresponding to a terminal fitting) connected to the end of the electric wire 11.

  As shown in FIG. 1, the electric wire 11 is formed by surrounding an outer periphery of a wire core (corresponding to a conductor) 13 with an insulating coating 14. The wire core 13 can be made of any metal such as aluminum, aluminum alloy, copper, copper alloy, or the like as required. The wire core 13 may be a stranded wire in which a large number of fine wires are brought together, or may be a single core wire.

  As shown in FIG. 1, the female terminal fitting 12 is formed by press-molding a metal plate (not shown) into a predetermined shape. The female terminal fitting 12 has an insulation barrel 15 that crimps the insulation coating 14 of the electric wire 11 from outside. On the left side of the insulation barrel 15 in FIG. 1, a wire barrel 16 (corresponding to a crimping portion) is formed which is connected to the insulation barrel 15 and caulked so as to hold the core wire of the electric wire 11 from the outside.

  On the left side of the wire barrel 16 in FIG. 1, a cylindrical connection portion 17 is connected to the wire barrel 16 and is electrically connected by fitting with a male terminal fitting (not shown) (corresponding to a counterpart terminal fitting). Is formed.

  Now, in FIG. 2, the wire barrel 16 in the state before crimping to the electric wire 11 is shown. The surface on the front side in FIG. 2 is the inner side when the electric wire 11 is caulked to the wire barrel 16 and is located on the electric wire 11 side. A plurality of recesses 18 are formed in the wire barrel 16 on the front side in FIG. The recess 18 extends in a direction (indicated by an arrow B in FIG. 2) intersecting with an axial direction (direction indicated by an arrow A in FIG. 2) of the electric wire 11 in a state where the wire barrel 16 is caulked to the electric wire 11. It has a substantially rectangular shape.

  As shown in FIG. 2, the recesses 18 form a pair (corresponding to a recess group) side by side with an interval in the axial direction of the electric wire 11 (direction indicated by the arrow A). A plurality of pairs of the recesses 18 and 18 are formed in a line at a certain interval in a direction intersecting the axial direction of the electric wire 11.

  Further, the pair of recesses 18 and 18 are formed in a plurality of rows (two rows in the present embodiment) at intervals in the axial direction of the electric wire 11. Further, the pair of recesses 18 and 18 adjacent to each other in the axial direction of the electric wire 11 are arranged at positions shifted from each other in the axial direction of the electric wire 11. Thereby, a pair of recessed part 18 and 18 is distribute | arranged as what is called a zigzag form as a whole.

  As shown in FIGS. 3 and 4, the cross section of the recess 18 has a substantially trapezoidal shape, and is formed in a wider shape from the bottom surface of the recess 18 toward the opening edge. An edge is formed at the opening edge of the recess 18.

  As shown in FIG. 5, the recess 18 is formed such that the area of the opening is larger than the area of the bottom surface. The pair of recesses 18 and 18 are arranged side by side at relatively close positions.

  The distance between the recesses 18 in the pair of recesses 18 and 18 in the axial direction of the electric wire 11 is set to 1 to 4 times the depth dimension of the recess 18.

  If the distance between the recesses in the axial direction of the electric wire is smaller than the depth dimension of the recesses, it is not preferable because it becomes difficult to process the recesses. On the other hand, if the interval between the recesses exceeds 4 times the depth of the recesses, it is not preferable because it cannot be distinguished from normal serrations. Moreover, since the whole recessed part group enlarges, it is not preferable.

  Next, the operation and effect of this embodiment will be described. Below, an example of the attachment process of the female terminal metal fitting 12 with respect to the electric wire 11 is shown. First, a metal plate is formed into a predetermined shape by press molding. At this time, you may form the recessed part 18 simultaneously.

  Then, the connection part 17 is formed by bending the metal plate material formed in the predetermined shape. At this time, the recess 18 may be formed.

  Subsequently, the insulation coating 14 of the electric wire 11 is removed to expose the wire core 13. With the wire core 13 placed on the wire barrel 16 and the insulation coating 14 placed on the insulation barrel 15, both barrels are caulked from the outside with respect to the electric wire 11 by a mold (not shown).

  When the wire barrel 16 is caulked to the wire core 13, the wire core 13 is pressed by the wire barrel 16 and plastically extends in the axial direction and extends. In the present embodiment, the concave portion 18 includes a pair of concave portions 18 and 18 formed side by side in the axial direction of the electric wire 11 with a space therebetween. Thereby, a pair of recessed parts 18 and 18 are arranged along with the position which adjoined comparatively (refer FIG. 9). Thereby, in this embodiment, a relatively large stress is concentrated on the wire core 13 in the region between the recesses 18 constituting the pair of recesses 18, 18. Then, at the opening edge located between the recesses 18, the oxide film formed on the surface of the wire core 13 is peeled off, and the new surface of the wire core 13 is exposed. The contact resistance between the electric wire 11 and the female terminal fitting 12 can be reduced by bringing the new surface of the wire core 13 into contact with the wire barrel 16.

  Furthermore, a relatively large stress is concentrated on the wire core 13, so that the deformation of the wire core 13 is promoted. Thereby, since the opening edge located between each recessed part 18 bites into the wire core 13, the contact resistance of the electric wire 11 and the female terminal metal fitting 12 can be made still smaller.

  In the present embodiment, the pair of recesses 18 and 18 are formed in a plurality of rows at intervals in the axial direction of the electric wire 11. Thereby, compared with the case where a pair of recessed parts 18 and 18 are formed in one row, the contact area of the wire core 13 and a terminal metal fitting can be enlarged. Thereby, the contact resistance between the electric wire 11 and a terminal metal fitting can be made still smaller.

  Further, when the wire barrel 16 is caulked to the electric wire 11, the wire barrel 16 also extends by being plastically deformed in the axial direction of the electric wire 11. Then, there is a concern that the recess 18 formed in the wire barrel 16 is stretched and the mechanical strength in the recess 18 is lowered.

  In view of this point, in the present invention, the pair of recesses 18 and 18 are configured to be formed side by side in a direction intersecting the axial direction of the electric wire 11. Thereby, a region where no recess 18 exists is formed between the pair of recesses 18, 18. Since the region where the recess 18 does not exist absorbs the force that plastically deforms the wire barrel 16 in the axial direction of the electric wire 11, it is possible to suppress the recess 18 from being greatly plastically deformed in the axial direction of the electric wire 11. As a result, the mechanical strength of the female terminal fitting 12 can be maintained.

  In the present embodiment, the pair of recesses 18 and 18 are formed in a plurality of rows at intervals in the axial direction of the electric wire 11. Thereby, compared with the case where a pair of recessed parts 18 and 18 are formed in one row, the contact area of the wire core 13 and a terminal metal fitting can be enlarged. Thereby, the contact resistance between the electric wire 11 and the female terminal fitting 12 can be further reduced.

  Moreover, in the area | region where a pair of recessed part 18 and 18 is not formed about the direction which cross | intersects the axial direction of the electric wire 11, the wire core 13 and the opening edge of each recessed part 18 do not slide. Then, we are anxious about the contact resistance between the electric wire 11 and the female terminal metal fitting 12 becoming non-uniform | heterogenous.

  In view of the above points, in the present embodiment, the pair of recesses 18 and 18 are configured to be disposed at positions shifted from each other in the axial direction of the electric wire 11. Thereby, about the axial direction of the electric wire 11, each recessed part 18 group can be distributed and arranged. Then, since the wire core 13 and each recessed part 18 are slidably contacted on the average with respect to the axial direction of the electric wire 11, the contact resistance between the electric wire 11 and the female terminal metal fitting 12 can be equalized.

  Moreover, in this embodiment, the space | interval of each recessed part 18 about the axial direction of the electric wire 11 in each pair of recessed parts 18 and 18 is set to 1-4 times the depth dimension of the recessed part 18. As shown in FIG.

  If the distance between the recesses 18 in the axial direction of the electric wire 11 is smaller than the depth dimension of the recess 18, processing of the recess 18 becomes difficult, which is not preferable. On the other hand, if the interval between the recesses 18 exceeds 4 times the depth dimension of the recesses 18, it is not preferable because it cannot be distinguished from normal serrations. Moreover, since a pair of recessed part 18 and 18 enlarges as a whole, it is unpreferable.

  In addition, when the wire core 13 is made of aluminum or an aluminum alloy, in order to break the oxide film formed on the surface of the wire core 13 and reduce the contact resistance, the wire is made with a high compression ratio (for example, about 40 to 70%). It is necessary to caulk the barrel 16 to the wire core 13. In such a case, the present embodiment is extremely effective. The compression rate is defined by {(conductor area after compression) / (conductor area before compression)} × 100.

<Embodiment 2>
Next, a second embodiment of the present invention will be described with reference to FIGS. In the present embodiment, except that the distance between the pair of recesses 18 and 18 is narrower than that of the first embodiment, the configuration is substantially the same as that of the first embodiment. Is omitted.

  According to the present embodiment, the distance between the pair of recesses 18 and 18 is narrower than that of the first embodiment, so that in the region between the recesses 18 constituting the pair of recesses 18 and 18, A relatively larger stress is concentrated on the wire core 13. Thereby, since the opening edge located between each recessed part 18 can be made to bite with respect to the wire core 13, the contact resistance of the electric wire 11 and the female terminal metal fitting 12 can be made still smaller.

<Embodiment 3>
Next, Embodiment 3 of the present invention will be described with reference to FIG. In the present embodiment, the pair of recesses 18 and 18 are formed in three rows at intervals in the axial direction of the electric wire 11. Moreover, a pair of recessed parts 18 and 18 adjacent to the axial direction of the electric wire 11 are shifted | deviated and arrange | positioned below in FIG. Since the configuration other than the above configuration is substantially the same as that of the first embodiment, the same members are denoted by the same reference numerals, and redundant description is omitted.

  According to this embodiment, the pair of recesses 18 and 18 are formed in three rows in the axial direction of the electric wire 11. Thereby, since the contact area between the electric wire 11 and the female terminal metal fitting 12 can be enlarged, contact resistance can be made still smaller.

  Further, since the dispersibility of the pair of recesses 18 in the wire barrel 16 is improved, the contact resistance between the electric wire 11 and the female terminal fitting 12 can be made more uniform.

<Other embodiments>
The present invention is not limited to the embodiments described with reference to the above description and drawings. For example, the following embodiments are also included in the technical scope of the present invention.
(1) In the present embodiment, the recess group is a pair of recesses 18, 18. However, the present invention is not limited to this, and the recess group may include three or more recesses 18.
(2) In the present embodiment, the pair of recesses 18 and 18 are arranged with a certain interval in the direction intersecting the axial direction of the electric wire 11, but the present invention is not limited to this, and the stress distribution in the wire barrel 16 is not limited thereto. Depending on, the interval between the pair of recesses 18 may be varied.
(3) In the present embodiment, the pair of recesses 18 and 18 are configured to form a plurality of rows with a certain interval in the axial direction of the electric wire 11, but the present invention is not limited to this, and the axial direction of the electric wire 11 is not limited thereto. The distance between the pair of recesses 18, 18 may not be equal and may be varied according to the stress distribution in the wire barrel 16.
(4) In the present embodiment, the pair of recesses 18 and 18 adjacent to each other in the axial direction of the electric wire 11 are arranged so as to be shifted in the axial direction of the electric wire 11. , 18 may be formed in alignment with respect to the axial direction of the electric wire 11 and the direction intersecting the axial direction.
(5) The depth dimensions of the recesses 18 may all be the same, or may differ depending on the site where the recesses 18 are formed.
(6) In the present embodiment, the terminal fitting is the female terminal fitting 12, but is not limited thereto, and may be a male terminal fitting, or a shape in which a through-hole penetrating the disk is formed (a so-called LA terminal). ). That is, the connection part 17 of a terminal metal fitting can take arbitrary shapes as needed.
(7) In the present embodiment, the electric wire 11 is a covered electric wire. Can be used. The conductor of the electric wire 11 may be the core 13 of the covered electric wire, or may be the central conductor of the shielded electric wire or the braided wire, and can take any configuration as necessary.
(8) Three or more barrel pieces of the insulation barrel 15 may be alternately formed from the left and right sides, or only one may be formed.
(9) The pair of recesses 18 and 18 may be formed in two rows, three rows, or five rows or more in the axial direction of the electric wire 11.

The principal part expanded side view of the wire harness of Embodiment 1 in this embodiment. The principal part enlarged plan view which shows the state of the wire barrel before crimping to an electric wire III-III sectional view in FIG. IV-IV sectional view in FIG. The principal part expansion perspective view which shows a pair of recessed part The principal part enlarged plan view which shows the state of the wire barrel of the female terminal metal fitting which concerns on Embodiment 2. FIG. VII-VII line sectional view in FIG. The principal part expansion perspective view which shows a pair of recessed part The principal part enlarged plan view which shows the state of the wire barrel of the female terminal metal fitting which concerns on Embodiment 3. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Wire harness 11 ... Electric wire 12 ... Female terminal metal fitting (terminal metal fitting)
13 ... Wire core 14 ... Insulation coating 16 ... Wire barrel (crimp)
17 ... Connection 18 ... Recess

Claims (11)

A terminal fitting having a crimped portion crimped from the outside to the end of the electric wire, and a connecting portion connected to the counterpart terminal fitting connected to the crimped portion,
On the surface on the wire side of the crimp portion, a recess group is formed that includes a plurality of recesses that extend in a direction intersecting the axial direction of the wire and are arranged at intervals in the axial direction of the wire. The terminal fitting is characterized in that a plurality of the recess groups are formed side by side in a direction intersecting with the axial direction of the electric wire. It is a terminal metal fitting of Claim 1, Comprising: The space | interval of each said recessed parts about the axial direction of the said electric wire in each said recessed part group is set to 1-4 times the depth dimension of the said recessed part. Terminal fittings characterized by 3. The terminal fitting according to claim 1, wherein the recess group is formed in a plurality of rows at intervals in the axial direction of the electric wire. It is a terminal metal fitting of Claim 3, Comprising: The said recessed part group adjacent to the axial direction of the said electric wire is distribute | arranged to the position mutually shifted | deviated about the axial direction of the said electric wire. 5. The terminal fitting according to claim 1, wherein the recess group includes a pair of recesses. A wire harness comprising an electric wire including a conductor, and a terminal fitting connected to the conductor exposed from an end of the electric wire,
The terminal fitting includes a crimping portion that is caulked from the outside to the end of the electric wire, and a connection portion that is connected to the mating terminal fitting in connection with the crimping portion,
On the surface on the wire side of the crimp portion, a recess group is formed that includes a plurality of recesses that extend in a direction intersecting the axial direction of the wire and are arranged at intervals in the axial direction of the wire. The said recessed part group is formed in multiple sets along with the space | interval in the direction which cross | intersects the axial direction of the said electric wire, The wire harness characterized by the above-mentioned. It is a wire harness of Claim 6, Comprising: The space | interval of each said recessed part about the axial direction of the said electric wire in each said recessed part group is set to 1-4 times the depth dimension of the said recessed part. Wire harness characterized by The wire harness according to claim 6 or 7, wherein the recess group is formed in a plurality of rows at intervals in the axial direction of the electric wire. It is a terminal metal fitting of Claim 8, Comprising: The said recessed group adjacent to the axial direction of the said electric wire is distribute | arranged to the position mutually shifted | deviated about the axial direction of the said electric wire, The wire harness characterized by the above-mentioned. The wire harness according to any one of claims 6 to 9, wherein the recess group includes a pair of recesses. It is a wire harness as described in any one of Claim 6 thru | or 10, Comprising: The said conductor consists of aluminum or aluminum alloy, It is characterized by the above-mentioned.

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