JP2015222737A - Connection structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a connection structure that can ensure reliable water-stop performance by forming, at a front end part of at least one of barrel pieces and a barrel bottom surface, an engaging part for engaging the barrel bottom surface and the barrel pieces when a crimp allowable part is brought into a crimped state.SOLUTION: A connection structure comprises a crimp contact 10 including barrel pieces 32 and a barrel bottom surface 31, which constitute a crimp allowable part that crimps at least a conductor exposed part of a wire tip. The barrel pieces are respectively disposed on both sides of the barrel bottom surface in the width direction thereof. The barrel pieces are formed so that their length in the longitudinal direction thereof is longer than the length of the conductor exposed part, and are formed continuously in the longitudinal direction in order to continuously integrally surround from the conductor exposed part to the front end of an insulation coating. An engaging part 34 for engaging the barrel bottom surface and the barrel pieces when the crimp allowable part is brought into a crimped state is formed at a front end part of at least one of the barrel pieces and the barrel bottom surface.

Description

  The present invention relates to a connection structure using, for example, a crimp terminal attached to a connector or the like for connecting an automobile wire harness.

In recent automobiles, various electric devices are equipped, and their electric circuits are becoming more and more complicated, and a stable power supply is indispensable. As described above, an automobile equipped with various electrical equipments has a wire harness in which covered electric wires are bundled, and the wire harnesses are connected with a connector to constitute an electric circuit.
These connectors have a crimp terminal in which a covered electric wire is crimped and connected at a crimping portion, and are configured to fit a male connector and a female connector.

  In an electric circuit configured by such an electrical connection, when moisture enters from the crimped portion between the crimp terminal and the coated wire mounted inside the connector, the surface of the wire conductor constituting the coated wire is corroded and the conductivity is lowered. There was a problem such as.

  Such a problem is that there is a gap between the insulation barrel that crimps the tip portion of the insulation coating of the coated wire in the crimping portion and the wire barrel that crimps the exposed portion of the wire conductor exposed on the tip side of the insulation coating. This is considered to be caused by the exposed end portion of the insulating coating.

  Therefore, in order to integrally surround from the tip of the insulation coating to the tip of the wire conductor, it is possible to prevent intrusion of moisture by using a crimp terminal having a barrel in which a wire barrel and an insulation barrel are integrated. Conceivable. However, in recent complicated electric circuits, it is necessary to ensure more stable conductivity, and the above crimp terminal is not sufficient.

In addition, there is an increasing number of electric vehicles and hybrid vehicles that use wire harnesses more frequently than gasoline vehicles at the time when reduction of carbon dioxide emissions (CO ₂ emissions) from vehicles is required. In all automobiles, including gasoline cars, the weight reduction of vehicles has a significant impact on fuel efficiency. Therefore, not only copper (or copper alloys) but also aluminum (or aluminum alloys) are used for wire harnesses and battery cables. To reduce the weight.

  When such an aluminum wire made of aluminum or an aluminum alloy is crimped and connected to a crimp terminal made of copper or a copper alloy, an electrochemical reaction occurs when moisture such as dew condensation or seawater intervenes between the two contact portions, There is a problem that a noble metal such as tin plating, gold plating, copper alloy, etc. of the terminal material corrodes a base metal such as aluminum or aluminum alloy, that is, a different metal corrosion (hereinafter referred to as “electrolytic corrosion”). .

  In particular, when the wire conductor is crimped with a barrel, the gap between the strands extends in the longitudinal direction of the strands due to the position of the strands constituting the wire conductor and the slight difference in conditions during press crimping (FIG. 2). , See gap 3 shown in FIG. 3), and among the crimped portions between the crimp terminal and the covered electric wire, moisture penetrates from the crimp portion between the front end side of the exposed conductor where the insulation coating is peeled off and the crimp terminal. Then, there is a problem that this moisture enters into the gap due to a capillary phenomenon, and electrolytic corrosion occurs due to a difference in ionization tendency between a noble metal species and a base metal.

  Due to this electrolytic corrosion, the aluminum wire crimped at the crimping portion of the crimp terminal is corroded, dissolved, or disappeared, and eventually the electrical resistance increases, and as a result, it may not be able to perform a sufficient conductive function. In the case of using an electric wire, there is a need for more reliably preventing moisture from entering.

Various documents have been proposed for improving the water stop performance of a connection structure using a crimp terminal. For example, Patent Documents 1 and 2 below are one of them.
Patent Document 1 also describes resin molding of a mold resin as a waterproof material on the pressure-bonded portion in order to improve water stopping performance. Moreover, in patent document 2, when a crimp terminal is crimped to a covered electric wire, a contact layer that maintains a contact state so that a gap for moisture to enter does not occur at a contact portion between the barrel piece of the crimp terminal and the conductor of the covered electric wire. It is described to provide.

  However, since the mold resin described in Patent Document 1 and the resin used for the contact layer described in Patent Document 2 are organic materials, they are lower in strength and inferior in heat resistance than metal materials.

  For example, when the connection structure is applied as an automotive part such as for connecting an automotive wire harness, it will stop at the initial stage if the time of exposure to a high temperature environment becomes long during a long period of use of 10 to 20 years. What satisfies the water performance is that a gap is formed at the interface between the connection structure and the mold resin, which are generally made of a metal material, or at the interface between the connection structure and the contact layer. It may not be possible.

  Further, when the connection structure is applied as an automotive part, if the time of exposure to a high temperature environment becomes long, the above-mentioned resins and other rubbers generally used as seal members are likely to be deteriorated, and are originally required. There is a risk that the water performance will be reduced.

  As described above, when the water stop performance is lowered, moisture permeates between the conductor and the insulating coating covering the conductor, the conductor is corroded, the contact resistance between the conductor and the crimp terminal is increased, and the electric resistance is increased. Thus, there arises a problem that the conductivity is lowered.

JP 2010-135121 A JP 2010-205583 A

  In view of this, the present invention forms an engaging portion that engages the bottom surface of the barrel and the barrel piece when the crimping allowable portion is brought into the crimped state at the tip of at least one of the barrel piece and the bottom surface of the barrel. An object of the present invention is to provide a connection structure that can ensure reliable water stopping performance.

The present invention provides a covered electric wire having an electric wire tip portion having a conductor exposed portion that is exposed by covering the electric wire conductor with an insulating coating and peeling off the insulating coating on the tip side, and at least the conductor exposure of the electric wire tip portion. A connecting structure comprising a barrel piece that constitutes a crimping allowable portion for crimping a portion and a crimp terminal having a barrel bottom surface, wherein the barrel pieces are arranged on both sides in the width direction of the barrel bottom surface, and the barrel The piece is continuously formed in the longitudinal direction so that the length in the longitudinal direction is longer than the length of the exposed portion of the conductor, and the piece is continuously and integrally surrounded from the exposed portion of the conductor to the tip of the insulating coating. An engagement portion is formed at the tip of at least one of the barrel piece and the barrel bottom surface to engage the barrel bottom surface and the barrel piece when the crimping permission portion is brought into a crimped state. Features To.
The above-mentioned engaging portion may be a combination of an engaging concave portion and an engaging convex portion, or may be a structure in which only the engaging concave portion is set and the barrel piece is press-fitted into the engaging concave portion during crimping. Alternatively, a structure in which only the engaging convex portion is set and the engaging convex portion bites into the barrel piece at the time of pressure bonding may be used.

Since the connecting structure of the present invention has an engaging portion that engages the barrel bottom surface and the barrel piece, when the crimping allowable portion is brought into the crimping state, the barrel piece is closely attached to the barrel bottom surface by the engaging portion. The engaged state can be ensured.
Therefore, it is possible to ensure a water-stopping performance that is remarkably superior compared to a structure in which the barrel piece is simply overlapped with the bottom surface of the barrel, and in particular, the above-mentioned engaging portion is formed at the tip of the barrel piece and the bottom surface of the barrel. Therefore, it is possible to prevent the intrusion of moisture at the site where the intrusion of moisture is most concerned (the tip of the crimping portion).
Therefore, it is possible to obtain a sufficiently excellent waterproof performance without sealing the crimped portion between the crimp portion and the wire tip portion with, for example, a waterproof material or a sealing material such as a mold resin for waterproofing or rubber. it can.

Specifically, when the connection structure is exposed to high temperatures and humidity or severe environments with severe changes in temperature and humidity over a long period of time, the resin and rubber that are commonly used as waterproofing materials and sealing materials will be altered and originally required. There is a risk that the water stop function will deteriorate.
On the other hand, the connection structure of the present invention ensures a sufficiently high waterproof performance over a long period of time without sealing the crimped portion between the crimped portion and the wire tip with a waterproof material or a sealing material. be able to.

  In general, the waterproof material and the seal material are formed of a resin material, and the crimp portion between the crimp portion and the wire tip is formed of a metal material. In the case of a configuration sealed with a material, the crimped portion is easily separated from the waterproofing material and the sealing material because it is a different material, and moisture enters through the gap between the waterproofing material and the sealing material and the metal material. It becomes easy.

  On the other hand, the connection structure of the present invention engages the bottom surface of the barrel and the barrel piece when the crimping allowable portion is brought into a crimped state at the tip of at least one of the barrel piece and the bottom surface of the barrel. Since the joint portion is formed, it is possible to secure a sufficiently good water-stopping performance without sealing the crimping portion with a waterproofing material or a sealing material. As in the case of the sealed structure, the waterproofing material and the sealing material are peeled off from the crimped part, and water does not enter from each other's interface. Can be secured.

Furthermore, since the connection structure of the present invention does not need to be subjected to water-stopping treatment such as sealing with a waterproof material or a sealing material, the number of manufacturing steps can be increased.
Specifically, if the crimping part between the crimping part and the wire tip in the connection structure is subjected to a water-stop treatment such as providing a mold resin or contact layer, the manufacturing efficiency of the connection structure increases, resulting in poor production efficiency. Further, since a waterproof material such as a mold resin and a sealing material made of PET, FEP, nylon, and PP are required, there arises a problem that the material cost and the management cost of the material increase.

  On the other hand, the connection structure of the present invention has a crimping between the crimping part and the wire tip as in the case where the crimping part between the crimping part and the wire tip is sealed with a sealing material. Since it is not necessary to perform water-stopping treatment such as sealing the part with a sealing material, the manufacturing process can be simplified and the efficiency can be improved, and a waterproof material and a sealing material are not required. Costs and management costs can be reduced.

In addition, since the connection structure of the present invention does not have a waterproof material or a seal material between the crimping portion and the wire tip portion, it ensures excellent conduction performance between the crimping portion and the wire tip portion. be able to.
In detail, most of the resins and rubbers are generally insulative, and some of the resins also contain conductive resins, but even if they are conductive resins, they are generally used as the constituent material for crimp terminals. It is a material that is extremely low in electrical conductivity compared to the above-mentioned copper and tin.

  When placing such a waterproof or sealing material made of a material with low conductivity or an insulating material in the vicinity of the crimping part between the crimping part and the wire tip part that needs to ensure continuity, it is contrary to the intention. If there is a displacement of the placement position or the crimping conditions change, there is a risk of crimping with the waterproofing material or sealing material interposed between the wire conductor and the crimping terminal. If the sealing material is interposed, there is a risk of hindering the conduction performance.

  On the other hand, since the connection structure of the present invention can ensure a sufficiently high waterproof performance without sealing the crimping portion with a sealing material, the crimping portion between the crimping portion and the wire tip portion is waterproof. In the case of sealing with a sealing material, there is no risk of accidental intervention due to the waterproof material and the sealing material, and excellent conduction performance between the crimping portion and the wire tip portion can be secured stably.

As an aspect of the present invention, the pressure-bonding allowable portion allows pressure-bonding between the barrel-to-barrel pressure-bonding portion that allows pressure-bonding between the barrel piece and the bottom of the barrel at the front portion of the pressure-bonding-permitted portion, and crimping of the conductor exposed portion at the tip of the electric wire. A conductor crimping permitting portion and a coating crimping permitting portion permitting crimping of the insulation coating on the tip of the electric wire, and the engaging portion is formed on at least one of the barrel piece and the barrel bottom surface of the inter-barrel crimping permitting portion can do.
With the above-described configuration, the engaging portion can be formed in the inter-barrel press allowable portion that allows the barrel piece and the barrel bottom surface to be pressed in the front portion of the press allowable portion of the press allowable portion.
That is, since the crimping allowable portion between the barrels is a portion where the electric wire conductor is not interposed between the barrel bottom surface and the barrel piece, the tight engagement between the barrel piece and the barrel bottom surface by the engaging portion is influenced by the electric wire conductor. Without intruding, and it is possible to more reliably prevent moisture from entering.

As an aspect of the present invention, the engaging portion can be continuously formed on the barrel bottom surface and the pair of barrel pieces.
With the configuration described above, the engagement portion can be easily formed and the formation space of the engagement portion is relatively narrow as compared with the structure in which the engagement portion is formed to be separated in the longitudinal direction of the covered electric wire. Even in a space, the engaging portion can be formed appropriately.

Moreover, as an aspect of the present invention, a plurality of the engaging portions can be formed.
With the above-described configuration, water can be stopped by a plurality of engaging portions, so that the water stopping effect can be further improved.

Moreover, as an aspect of the present invention, a transition portion is integrally formed at the tip of the crimp terminal, and a drain hole can be formed at the bottom of the transition portion.
With the configuration described above, water attached to or accumulated in the transition part can be discharged from the drain hole, so that water tends to enter the inside of the crimping part from the tip of the crimping part in which the crimping allowable part is in the crimped state. Can be prevented, and further improvement in water stopping performance can be achieved.

Further, as an aspect of the present invention, the drain hole can be formed such that the rear end of the hole edge coincides with the tip of the crimping portion in which the crimping allowable portion is in a crimped state.
With the configuration described above, it is possible to improve the drain performance while appropriately securing the crimping portion.
That is, when the hole edge rear end of the drain hole is excessively separated from the front end of the crimping part, water easily collects in the step part between the tip of the crimping part and the transition part. In the case of a structure in which the rear edge of the hole edge is located behind the tip of the crimping part, the crimping part and the drain hole overlap with each other, so that the crimping part is reduced and securing of the sufficient crimping part is hindered. In addition, a step portion is separately formed between the drain hole and the rear surface of the transition portion, and water easily collects in this portion.
On the other hand, the connection structure of the present invention makes the transition at the drain hole without causing the drain hole to adversely affect the crimping part by matching the rear end of the hole edge of the drain hole with the tip of the crimping part. The water adhering to or accumulating in the portion can be discharged to prevent the water from entering the inside of the crimping portion.

Further, as an aspect of the present invention, a barrel overlapped portion in which at least a part of the pair of barrel pieces is overlapped with each other is formed on a pressure-bonded portion in which the pressure-bonding allowable portion is in a pressure-bonded state. The barrel piece located at the outer barrel piece is set as the outer barrel piece, the barrel piece located inside the outer barrel piece is set as the inner barrel piece, and the outer end of the outer barrel piece in the barrel overlap portion is the width of the crimping portion. It can be made to be located outside from the center in the direction beyond the center in the width direction.
With the above-described configuration, the outer end of the outer barrel piece in the barrel overlapping portion is located outward from the center in the width direction of the crimping portion and beyond the center in the width direction. The amount of wrapping can be secured, and this overlap structure can prevent water from entering the inside of the crimping portion.

Moreover, as an aspect of the present invention, the outer end of the outer barrel piece in the barrel overlapping portion can be folded back so as to wind up the outer end portion of the crimping portion.
With the configuration described above, the outer end of the outer barrel piece in the barrel overlapped portion is folded back so as to wind up the outer end portion of the crimping portion, so in addition to the overlap structure described above, The close contact state between the outer barrel piece and the inner barrel piece can be maintained, whereby the water stopping performance can be further improved.

  According to the present invention, at the tip of at least one of the barrel piece and the barrel bottom surface, the engagement portion that engages the barrel bottom surface and the barrel piece is formed when the crimping permission portion is brought into the crimped state. The connection structure which ensures reliable water stop performance can be provided.

External view of crimped connection structure Configuration illustration of crimp connection structure Cross-sectional view in the width direction of the crimped connection structure Configuration illustration of female crimp terminal and covered wire Configuration illustration of female crimp terminal Configuration illustration of female crimp terminal Sectional drawing which shows structure of engaging part Sectional drawing which shows the winding structure of the outer barrel piece outer end

An embodiment of the present invention will be described below with reference to the drawings.
The crimp connection structure 1 of the present embodiment includes a covered electric wire 200 including an electric wire tip portion 200a having a conductor exposed portion 201a that is exposed by covering the electric wire conductor 203 with an insulating coating 202 and peeling off the insulating coating 202 on the tip side. And a female crimp terminal 10 having a barrel piece 32 and a barrel bottom surface 31 that constitute a crimping allowance portion 30A that allows crimping to the covered electric wire 200, and at least the conductor exposed portion 201a of the wire tip portion 200a. Are integrally formed by pressure bonding with the pressure bonding allowable portion 30A.

The female crimp terminal 10 includes a pair of barrel pieces 32 on both sides in the width direction Y of the barrel bottom surface 31, and the barrel pieces 32 are formed so that the length in the longitudinal direction X is longer than the length of the conductor exposed portion 201 a. It is formed continuously in the longitudinal direction X so as to continuously and integrally surround the exposed portion 201a to the coating tip 202a at the tip of the insulating coating 202.
A barrel overlapped part D is formed in which at least a part of the pair of barrel pieces 32 are overlapped with each other on the crimping part 30 to which the crimping allowable part 30A is crimped.

Here, in the barrel overlap portion D, the barrel piece 32 positioned outside is set as the outer barrel piece 32a, and the barrel piece 32 positioned inside the outer barrel piece 32a is set as the inner barrel piece 32b.
In addition, an engagement portion 34 that engages the barrel bottom surface 31 and the barrel piece 32 when the crimping permission portion 30A is brought into the crimped state is formed at the tip of at least one of the barrel piece 32 and the barrel bottom surface 31. Has been.

Hereinafter, the above-described crimp connection structure 1 and female crimp terminal 10 will be described in detail with reference to the drawings.
FIG. 1A is a perspective view of the crimping connection structure 1, and FIG. 1B is a perspective view of the crimping connection structure that constitutes the crimp 301 in a pre-crimped state.
2A is a longitudinal sectional view of the crimped connection structure 1 taken along the longitudinal direction at the center in the width direction Y, FIG. 2B is an enlarged view of a portion X1 in FIG. 2A, and FIG. ) Is an enlarged view of a portion X2 in FIG.
3A is a cross-sectional view taken along line AA in FIG. 2A, FIG. 3B is a cross-sectional view taken along line BB in FIG. 2A, and FIG. 3C is a cross-sectional view taken from FIG. FIG. 3D is a sectional view taken along the line DD of FIG. 2A, FIG. 3E is a sectional view taken along the line EE of FIG. 2A, and FIG. FIG. 5 is a cross-sectional view taken along line FF in FIG.
FIG. 4 is an external view of the female crimp terminal 10 and the tip side portion of the covered electric wire 200.
5 (a) is a right side view of the female crimp terminal 10, FIG. 5 (b) is a longitudinal sectional view of the female crimp terminal 10 taken along the longitudinal direction at the center in the width direction Y, and FIG. 5 (c). FIG. 3 is a rear view of the female crimp terminal 10.
6 (a) is a development view of the female crimp terminal 10, FIG. 6 (b) is an enlarged view of the main part of FIG. 6 (a), and FIG. 6 (c) is an AA line view of FIG. 6 (b). 6D is a cross-sectional view taken along line BB in FIG. 6B, FIG. 6E is a cross-sectional view taken along line CC in FIG. 6B, and FIG. FIG. 7 is a sectional view taken along the line D-D in FIG.
7A is a cross-sectional view showing a section of the engaging portion in the female crimp terminal 10 of FIG. 4, FIG. 7B is a cross-sectional view showing another embodiment of the engaging portion structure, and FIG. (C) is sectional drawing which shows other embodiment of an engaging part structure.

  The crimp connection structure 1 of the present embodiment has a configuration in which the female crimp terminal 10 is crimped and connected to the tip of the covered electric wire 200 by the crimp portion 30, and is attached to the crimp portion of the covered electric wire 200 and the female crimp terminal 10. Constitutes the crimping portion 30 in which the crimping allowable portion 30A is crimped to the wire tip portion 200a, that is, the conductor exposed portion 201a and the coated tip portion 202a (see FIG. 1A).

As shown in FIG. 1A, the crimping portion 30 constitutes an inter-barrel crimping portion 30a, a conductor crimping portion 30b, and a covering crimping portion 30c in order from the front side (front end side) to the rear end side in the longitudinal direction. .
2 and 4, the inter-barrel crimping portion 30a is a crimping portion obtained by crimping the barrel bottom surface 31 and the barrel piece 32 in the inter-barrel crimping permitting portion 30Aa of the crimping permitting portion 30A, and the conductor crimping portion 30b is The crimping portion 30A of the crimping allowable portion 30A is a crimped portion that is crimped to the exposed conductor portion 201a, and the crimping portion 30c is a crimping portion of the crimping permitting portion 30Ac of the crimping allowable portion 30A that is crimped to the insulating coating 202. is there.

  As shown in FIG. 4, the coated electric wire 200 that is crimped by the crimping portion 30 and connected to the female crimp terminal 10 includes a plurality of aluminum core wires 201 in which aluminum strands are bundled with an insulating coating 202 that is made of an insulating resin. Covered and configured. On the distal end side of the covered electric wire 200, an electric wire distal end portion 200a having a conductor exposed portion 201a in which the insulating coating 202 on the distal end side is peeled to expose the electric wire conductor 203 is configured.

The female crimp terminal 10 includes a box portion 20 that allows insertion of an insertion tab in a male connector (not shown) from the front, which is the front end side in the longitudinal direction X, to the rear of the box portion 20. The pressure admissible portion 30A disposed via a transition portion 20a having a predetermined length is integrally formed. The longitudinal direction X is a direction that coincides with the longitudinal direction X of the covered electric wire 200 to be connected by being crimped at the box portion 20.
The female crimp terminal 10 is an open barrel type terminal that is three-dimensionally configured by punching and bending a copper alloy strip such as brass whose surface is tin-plated (Sn-plated).

The box portion 20 is formed of an inverted hollow square column body, and has a dimple 21a that is bent toward the rear in the longitudinal direction X and contacts an insertion tab (not shown) of the male connector to be inserted. An elastic contact piece 21 is provided.
The ceiling part 22 (22a, 22b) of the box part 20 which is a hollow quadrangular column body overlaps with an extended part extending outward in the width direction Y with respect to the side part 23 (23a, 23b) (see FIG. 5). It is constructed by bending.

As shown in FIGS. 4 and 5, the crimping allowable portion 30 </ b> A includes a barrel bottom surface 31, and a pair of barrel pieces 32 (32 </ b> Aa, 32 </ b> Ab) that extend obliquely outward from both sides in the width direction Y of the barrel bottom surface 31. It consists of.
The pair of barrel pieces 32 is composed of a long barrel piece 32Aa and a short barrel piece 32Ab, and the long barrel piece 32Aa, as shown in FIG. It is located on the right side in the width direction Y and is formed slightly longer than the protruding length of the short barrel piece 32Ab located on the left side in the width direction Y.

  As shown in FIG. 4, the length Xb of the barrel piece 32 in the longitudinal direction X is a wire exposed portion exposed in front of the longitudinal direction X from the coating tip 202 a that is the tip of the insulating coating 202 on the front side in the longitudinal direction X. It is formed longer than the exposed length Xw in the longitudinal direction X of 201a.

  Specifically, the crimping allowable part 30A includes an inter-barrel crimping allowable part 30Aa, a conductor crimping allowable part 30Ab, and a covering crimping allowable part 30Ac in order from the front to the rear in the longitudinal direction X, and these are integrated in the longitudinal direction X. Is formed. The inter-barrel press-allowing portion 30Aa of the press-bonding allowable portion 30A is a portion that allows press-bonding between the barrel piece 32 and the barrel bottom surface 31 in front of the press-bonding allowable portion 30A. The conductor crimping allowable portion 30Ab is a portion that allows crimping of the conductor exposed portion 201a of the wire tip portion 200a, and the coating crimping allowable portion 30Ac is a portion that permits crimping of the insulating coating 202 of the wire tip portion 200a.

  The conductor crimping allowance portion 30Ab and the coating crimping allowance portion 30Ac are respectively formed in a shape corresponding to the outer diameter of the wire conductor 203 and the insulation coating 202 to be crimped. The 30Ac barrel piece 32 is formed to have a longer inner peripheral length than the barrel piece 32 of the conductor crimping allowable portion 30Ab to which the aluminum core wire 201 is crimped.

  Further, as shown in FIG. 6, the crimping allowable portion 30 </ b> A is formed with a conductor engagement groove 33, a virtual barrel boundary line α, a front engagement portion 34, and a rear barrel engagement groove portion 35. Yes.

  The conductor engaging groove 33 is a groove formed continuously along the width direction Y from the barrel bottom surface 31 to the barrel pieces 32 on both sides on the inner surface of the conductor crimping allowable portion 30Ab in the crimping allowable portion 30A. A plurality of, for example, four are formed in parallel with each other at a predetermined interval in X.

  The virtual barrel boundary line α is a boundary portion between the barrel bottom surface 31 and the barrel piece 32 on the inner surface of the crimping allowable portion 30A, that is, a barrel bending portion β that bends the barrel piece 32 with respect to the barrel bottom surface 31 (FIG. 5C). In the reference direction) along the longitudinal direction.

  The front engaging portion 34 is formed on the inner surface of the tip end of the barrel piece 32 and the barrel bottom surface 31, that is, between the barrels of the pressing allowable portion 30 </ b> A. It is an engaging means for engaging the barrel bottom surface 31 and the barrel piece 32 when the crimping permission portion 30Aa is brought into the crimped state.

In this embodiment, as shown also in FIG. 7A, the engaging portion 34 is continuous with the engaging recess 34a located between the pair of virtual barrel boundary lines α and α, and the engaging recess 34a. A pair of engagement protrusions 34b formed on the inner surface of the barrel 32, and the engagement recesses 34a and the engagement protrusions 34b formed on the inner surface of the barrel bottom surface 31 are continuous in a straight line. In addition to being formed, a plurality of strips, for example, two strips are formed in parallel with each other at a predetermined interval in the longitudinal direction.
Here, the engagement concave portion 34a formed in the central portion of the crimping allowable portion 30A is a concave shape at the time of press working for punching a copper alloy strip and processing it into a developed shape of the female crimp terminal 10 shown in FIG. The engaging convex portion 34b formed on the inner surface of the barrel piece 32 outside the virtual barrel boundary line α is formed into a convex shape at the time of the above pressing. It can be formed using a lower mold having a surface.
That is, the engaging portion 34 is formed on the contact surface portion that makes contact in the vertical direction when the press-bonding allowable portion 30A is brought into the press-bonded state (see FIG. 3A).

  On the other hand, the rear barrel engaging groove portion 35 is formed by a rear barrel engaging groove 35a and a rear barrel engaged groove 35b, both of which are formed along the width direction Y in the covering press bonding allowance portion 30Ac in the press bonding allowance portion 30A. doing. A plurality of, for example, three rear barrel engaged grooves 35b are formed on the inner surface of the long barrel piece 32Aa in parallel with each other at a predetermined interval slightly narrower than the width of the rear barrel engaging groove 35a in the longitudinal direction X. ing.

  Between these three rear barrel engaged grooves 35b, 35b, there is a convex portion with respect to the rear barrel engaged groove 35b, and the convex portion is provided as a rear barrel engaging protrusion 35b. It is set to '.

  The rear barrel engaging groove 35a is formed along the width direction Y on the outer surface of the short barrel piece 32Ab, and a plurality of, for example, two are formed in parallel with each other at a predetermined interval in the longitudinal direction X. The rear barrel engagement groove 35a is formed at a position that coincides with the rear barrel engagement protrusion 35b 'in the longitudinal direction X.

By the way, as shown in FIGS. 6A and 6B, a transition portion 20a is integrally formed at the tip of the female crimp terminal 10 described above, and at the center position of the transition portion 20a which becomes the bottom after processing. A drain hole 40 is formed through.
The drain hole 40 described above is formed so that the rear end of the hole edge coincides with the tip of the crimping portion 30 in which the crimping allowable portion 30A is in a crimped state (see FIG. 2).

In this embodiment, as shown in FIG. 6, a round hole is exemplified as the drain hole 40, but this may be a square hole, and the hole edge rear end portion is formed with a diameter portion (or a straight portion). It may be a semicircular through hole (through hole), or may be an elliptical or polygonal hole.
In addition, in the figure, 201aa shows the front-end | tip of the electric wire exposure part 201a, Z shows the space | gap formed along the longitudinal direction between the aluminum core wires 201. FIG.

Below, the manufacturing process of the crimping | bonding connection structure 1 is demonstrated roughly.
First, a flat copper alloy strip is prepared, and this copper alloy strip is press punched to form a developed female crimp terminal 10 shown in FIG. 6 (a).
At this time, the conductor engaging groove 33, the engaging part 34, the barrel engaging groove part 35, and the drain hole 40 shown in FIG. 6B can be simultaneously formed. After the punching process, the elements 33, 34, 35, and 40 may be formed by pressing.

  Next, the box portion 20 is processed into a hollow rectangular column body by a well-known process, and the female crimp terminal 10 is formed into an open barrel type terminal shown in FIG. 4 by bending.

  Next, the covered electric wire 200 is arranged on the barrel bottom surface 31 of the open barrel type terminal shown in FIG. 4, and the two barrel pieces 32b and 32a are placed so that the outer barrel piece 32a is positioned outside the inner barrel piece 32b in this state. Temporary caulking is performed to achieve the pre-compression state shown in FIG.

Next, when the pre-crimped female crimp terminal 10 shown in FIG. 1B is caulked using the lower and upper molds for main caulking, the female crimp terminal 10 shown in FIG. Become.
2A, 2B, 2C, and 3A to 3F are sectional shapes of the respective parts of the crimped connection structure 1 of FIG. ).

As shown in FIG. 2B and FIG. 3A, when the inter-barrel press-bonding allowable portion 30Aa of the press-bonding allowable portion 30A is brought into the press-bonded state, the engaging portion that engages the barrel bottom surface 31 and the barrel piece 32. 3 is formed, after the crimping by crimping is completed, the engagement convex portions 34b of the inner barrel piece 32b and the outer barrel piece 32a are brought into close contact with the engagement concave portion 34a on the barrel bottom surface 31 side, and FIG. ), It is possible to prevent a moisture intrusion gap from being formed at the tip of the crimping portion 30, and to tightly fit the barrel bottom surface 31 and the barrel pieces 32a and 32b without any gap. .
Accordingly, it is possible to prevent moisture from entering the inside of the crimping portion 30 from the distal end side of the crimping portion 30 where the entry of moisture is most concerned, and it is possible to ensure sufficient water stopping performance.

Further, the barrel piece 32 in which the above-described engagement portion 34 is formed and the tip end portion of the barrel bottom surface 31, that is, the inter-barrel crimping allowable portion 30Aa are portions where the aluminum core wire 201 is not interposed during the crimping. Since the liquid-tight crimping state is not hindered by the aluminum core wire 201, the water stop performance can be improved.
Furthermore, since the above-mentioned engaging part 34 is formed in a plurality of strips (two strips in this embodiment) at intervals in the longitudinal direction, the water can be stopped by a plurality of stages before and after, Further improvement can be achieved.
3A, the inner surface of the barrel bottom surface 31 and the inner surface of the inner barrel piece 32b, the inner surface of the barrel bottom surface 31 and the inner surface of the outer barrel piece 32a, and the outer surface of the inner barrel piece 32b. And the inner surface of the outer barrel piece 32a may employ a configuration in which the engaging portion 34 is formed on the entire contact surface portion where the barrel element is vertically contacted or substantially the entire surface.

On the other hand, as shown in FIG. 2A, the aluminum core wire 201 bites into the conductor engagement groove 33 at a predetermined position of the conductor crimping portion 30b where the conductor engagement groove 33 is formed. With the close contact structure, the conductivity can be improved.
Further, as shown in FIG. 2 (c), an enlarged view of the portion X2 in FIG. 2 (a) is such that the rear barrel engagement protrusion 35b ′ bites into the rear barrel engagement groove 35a in the cover crimping portion 30c. The inner barrel piece 32b and the outer barrel piece 32a are brought into close contact with each other, so that moisture can be prevented from entering from the rear end side of the crimping portion 30 and water stopping performance can be further improved.

  Further, as shown in the cross-sectional structure of each part in FIGS. 3A to 3F, a part of the pair of barrel pieces 32 a and 32 b is mutually attached to the crimping part 30 in which the crimping allowable part 30 </ b> A is in the crimped state. The overlapped barrel overlap portion D is formed, and the outer end of the outer barrel piece 32a in the barrel overlap portion D is located outward from the width direction center of the crimping portion 30 beyond the width direction center. .

  Specifically, the inter-barrel crimping portion 30a in which the inter-barrel crimping allowable portion 30Aa shown in FIG. 3A is in a crimped state and the conductor crimping allowable portion 30Ab adjacent to the inter-barrel crimping allowable portion 30Aa shown in FIG. At the tip of the conductor crimping portion 30b with the tip crimped, the outer end of the outer barrel piece 32a is against a virtual line L1 connecting the center of curvature C1 of the barrel overlap portion D and the center of the crimping portion 30 in the width direction. It is set at a position of 30 degrees or more outward, and a sufficient amount of overlap between the inner barrel piece 32b and the outer barrel piece 32a is secured, so that water can enter the inside of the crimping portion 30 by this overlap structure. It has a structure that prevents this.

Further, in the conductor crimping portion 30b and the covering crimping portion 30c in which the conductor crimping allowable portion 30Ab and the covering crimping allowable portion 30Ac shown in FIGS. 3C to 3F are in a crimping state, the virtual center C2 of the crimping portion 30 is provided. With respect to a virtual vertical line L2 passing through, the outside of the outer barrel piece 32a is set at a position of 60 degrees or more outward, and a sufficient overlap amount between the inner barrel piece 32b and the outer barrel piece 32a is secured. Thus, this overlap structure prevents water from entering the inside of the crimping portion 30.
In short, the outer end of the outer barrel piece 32a in the barrel overlap portion D exceeds the center in the width direction from the center in the width direction of the crimping portion 30 in any of the cross-sectional positions in FIGS. 3 (a) to 3 (f). The outer barrel piece 32b and the outer barrel piece 32a are secured so as to obtain an adequate water-stopping effect.

  On the other hand, as shown in FIGS. 2 (a) and 2 (b), a drain hole 40 for discharging water or water adhering to or accumulating on the female crimp terminal 10 is formed at the center of the bottom of the transition portion 20a. Since the drain hole 40 is formed, water can be drained from the drain hole 40. In particular, water can enter the inside of the crimping part 30 from the tip of the crimping part 30 in the crimping allowable part 30A. It is possible to prevent the water stoppage performance.

  As described above, in the connection structure according to the embodiment shown in FIGS. 1 to 7A, the conductor exposed portion is formed by covering the electric wire conductor 203 with the insulating coating 202 and peeling off the insulating coating 202 on the distal end side. Crimp terminal provided with a covered wire 200 having a wire tip portion 200a having 201a, a barrel piece 32 and a barrel bottom surface 31 constituting a crimp allowance portion 30A for crimping at least the conductor exposed portion 201a of the wire tip portion 200a. (Refer to the female crimp terminal 10), wherein the barrel pieces 32 are arranged on both sides of the barrel bottom surface 31 in the width direction, and the barrel pieces 32 are arranged with the length of the conductor exposed portion. The length Xb in the longitudinal direction is longer than the length Xw (Xb> Xw), and the portion from the conductor exposed portion 201a to the tip of the insulating coating 202 is continuously and integrally surrounded. The barrel bottom surface 31 and the barrel piece 32 are formed when the crimping allowable portion 30A is brought into a crimped state at the tip of at least one of the barrel piece 32 and the barrel bottom surface 31. An engaging portion 34 to be engaged is formed (see FIGS. 1, 2, and 4).

According to this configuration, the engaging portion 34 that engages the barrel bottom surface 31 and the barrel piece 32 is formed. It is possible to ensure a state of being in close contact with 31 without a gap.
Therefore, it is possible to ensure a water stopping performance that is remarkably superior as compared with a structure in which the barrel piece 32 is simply overlapped with the barrel bottom surface 31. In particular, the above-described engaging portion 34 has the barrel piece 32 and the barrel bottom surface 31. Since it formed in the front-end | tip part, invasion of a water | moisture content can be prevented in the site | part (front-end | tip part of a crimping | compression-bonding part) where water | moisture content is most concerned, and high water stop performance can be exhibited.

  Further, the crimping allowable portion 30A includes a crimping allowable portion 30Aa between the barrels that allows the barrel piece 32 and the barrel bottom surface 31 to be crimped at a front portion of the crimping allowable portion 30A, and a crimping of the conductor exposed portion 201a of the wire tip 200a. A conductor crimping allowable portion 30Ab that permits the crimping of the insulating coating 202 of the wire tip portion 200a, and the engagement portion 34 includes the barrel piece 32 of the inter-barrel crimping allowable portion 30Aa. And formed on at least one of the barrel bottom 31 (see FIGS. 5 and 7A).

According to this configuration, the engaging portion 34 can be formed in the inter-barrel pressure-bonding allowable portion 30Aa that allows pressure-bonding between the barrel piece 32 and the barrel bottom surface 31 in the front portion of the pressure-bonding allowable portion 30A in the pressure-bonding allowable portion 30A. it can.
In other words, the inter-barrel crimping allowable portion 30 </ b> Aa is a portion where the electric wire conductor 203 is not interposed between the barrel bottom surface 31 and the barrel piece 32, and thus the close engagement between the barrel piece 32 and the barrel bottom surface 31 by the engaging portion 34. Can be performed more reliably without being influenced by the electric wire conductor 203, and the intrusion of moisture can be prevented even better.
Further, the engaging portion 34 is formed continuously on the barrel bottom surface 31 and the pair of barrel pieces 32 (see FIGS. 5B and 6B).

According to this configuration, the engagement portion 34 can be easily formed and the space for forming the engagement portion 34 can be reduced as compared with the structure in which the engagement portion 34 is formed to be separated in the longitudinal direction of the covered electric wire 200. Even in a relatively narrow limited space, the engaging portion 34 can be appropriately formed.
Furthermore, a plurality of the engaging portions 34 are formed (see FIGS. 5B and 6B).

According to this configuration, water can be stopped by the plurality of engaging portions 34, so that the water stopping effect can be further improved.
Moreover, a transition portion 20a is integrally formed at the tip of the crimp terminal 10,
A drain hole 40 is formed at the bottom of the transition portion 20a (see FIG. 2).

According to this configuration, water adhering to or accumulating in the transition portion 20a can be discharged from the drain hole 40, so that water can be introduced into the inside of the crimping portion 30 from the tip of the crimping portion 30 in which the crimping allowable portion 30A is in a crimped state. It is possible to prevent entry into the water and further improve the water stopping performance.
Further, the drain hole 40 is formed such that the rear end of the hole edge coincides with the tip of the crimping part 30 in which the crimping allowable part 30A is in a crimped state (see FIG. 2).

According to this configuration, it is possible to improve the drain performance while appropriately securing the crimping portion 30.
That is, when the hole edge rear end of the drain hole is excessively separated from the front end of the crimping part, water easily collects in the step part between the tip of the crimping part and the transition part. In the case of a structure in which the rear edge of the hole edge is located behind the tip of the crimping part, the crimping part and the drain hole overlap with each other, so that the crimping part is reduced and securing of the sufficient crimping part is hindered. In addition, a step portion is separately formed between the drain hole and the rear surface of the transition portion, and water easily collects in this portion.
On the other hand, in the connection structure of the present embodiment, the drain hole 40 does not adversely affect the crimping part 30 by making the hole edge rear end of the drain hole 40 coincide with the tip of the crimping part 30, The water adhering to or accumulating in the transition portion 20 a through the drain hole 40 can be discharged, and water can be prevented from entering the inside of the crimping portion 30.

  Furthermore, the pressure-bonding portion 30 in which the pressure-bonding allowable portion 30A is in a pressure-bonded state forms a barrel overlap portion D in which at least a part of the pair of barrel pieces 32 and 32 are overlapped with each other, and among the barrel overlap portions D, The barrel piece 32 positioned outside is set as the outer barrel piece 32a, the barrel piece 32 positioned inside the outer barrel piece 32a is set as the inner barrel piece 32b, and the outside of the outer barrel piece 32a in the barrel overlap portion D is set. The end is formed so as to be located outward from the center in the width direction of the crimping portion 30 beyond the center in the width direction (see FIG. 3).

  According to this configuration, since the outer end of the outer barrel piece 32a in the barrel overlap portion D is located outward from the center in the width direction of the crimping portion 30 beyond the center in the width direction, the inner barrel piece 32b and the outer barrel piece A sufficient amount of overlap with 32a can be ensured, and this overlap structure can prevent water from entering the crimping portion 32.

FIG. 7B shows another embodiment of the structure of the engaging portion, in which an engaging recess 34a is formed on the inner surface on the barrel bottom surface 31 side between a pair of virtual barrel boundary lines α and α.
When formed in this way, the inner barrel piece 32b is bent inward, and then the barrel piece 32a is bent inward so that the outer barrel piece 32a is positioned outside the inner barrel piece 32b, and then crimped. When the allowance portion 30A is caulked to form the crimping portion 30, a part of the inner barrel piece 32b is plastically deformed by the pressure applied during caulking and bites into the engaging recess 34a, and the same applies to a part of the outer barrel piece 32a. In addition, since the plastic deformation causes biting into the engagement recess 34a, the engagement recess 34a constituting the engagement portion can ensure that the barrel piece 32 is in close contact with the barrel bottom surface 31 without any gap, Water performance can be ensured.

FIG. 7C shows still another embodiment of the structure of the engaging portion, in which an engaging convex portion 34b is formed on the inner surface on the barrel bottom surface 31 side between the pair of virtual barrel boundary lines α and α.
When formed in this way, the inner barrel piece 32b is bent inward, and then the barrel piece 32a is bent inward so that the outer barrel piece 32a is positioned outside the inner barrel piece 32b, and then crimped. When the allowable portion 30A is caulked to form the crimping portion 30, the engaging convex portion 34b bites into a part of the inner barrel piece 32b by the pressure applied during caulking, and the outer barrel piece 32a is similarly engaged with the engagement portion 34a. Since the joint convex portion 34b bites in, the engagement convex portion 34b constituting the engaging portion can ensure that the barrel piece 32 is in close contact with the barrel bottom surface 31 without any gap, and ensures water stopping performance. Can do.
In the embodiment shown in FIGS. 7B and 7C, the other configurations, operations, and effects are almost the same as those in the previous embodiment, so FIGS. 7B and 7C. In the figure, the same parts as those in the previous figure are denoted by the same reference numerals, and detailed description thereof is omitted.

FIG. 8 shows another embodiment of the crimped connection structure, and in particular, a cross-sectional view showing a wound-back structure of the outer end of the outer barrel piece.
As shown in FIG. 8, in this embodiment, the outer end of the outer barrel piece 32a in the barrel overlap portion D is the outer end portion of the crimping portion 30, more specifically, the inter-barrel crimping portion corresponding to the virtual barrel boundary line α. The folded portion 30e is formed by folding the outer end portion 30b on one side of 30a so as to be wound.
As described above, when the outer end of the outer barrel piece 32a in the barrel overlap portion D is folded back so as to wind the outer end portion 30d of the crimping portion 30, the outer barrel piece 32a is wound on the outer end in addition to the overlap structure described above. The close-in folding structure allows the outer barrel piece 32a and the inner barrel piece 32b to be kept in close contact with each other, thereby further improving the water stopping performance.

In correspondence between the configuration of the present invention and the above-described embodiment,
The connection structure of the present invention corresponds to the crimp connection structure of the embodiment,
Similarly,
The crimp terminal corresponds to the female crimp terminal,
The present invention is not limited to the configuration of the above-described embodiment.

DESCRIPTION OF SYMBOLS 1 ... Crimp connection structure 10 ... Female type | mold crimp terminal 20a ... Transition part 30 ... Crimp part 30A ... Crimp allowance part 30Aa ... Inter-barrel crimping allowance part 30Ac ... Conductor crimping allowance part 30Ac ... Cover crimping allowance part 31 ... Barrel bottom face 32 ... Barrel piece 32a ... outer barrel piece 32b ... inner barrel piece 34 ... engagement portion 40 ... drain hole 200 ... covered wire 200a ... wire tip 201a ... conductor exposed portion 202 ... insulation coating 203 ... wire conductor D ... barrel overlap portion

Claims (8)

A covered electric wire having an electric wire tip having a conductor exposed portion that is exposed by covering the electric wire conductor with an insulating coating and peeling off the insulating coating on the tip side; and
A connection structure composed of a barrel piece and a crimp terminal provided with a barrel bottom surface that constitute a crimp-acceptable portion for crimping at least the conductor exposed portion of the wire tip,
The barrel pieces are arranged on both sides in the width direction of the barrel bottom surface,
The barrel piece has a length in the longitudinal direction longer than the length of the conductor exposed portion, and is continuous in the longitudinal direction so as to continuously and integrally surround from the conductor exposed portion to the tip of the insulating coating. Formed,
A connection structure in which at least one of the barrel piece and the bottom surface of the barrel is formed with an engagement portion that engages the bottom surface of the barrel and the barrel piece when the crimping permission portion is brought into a crimped state. The crimping-permitted portion includes an inter-barrel crimping permitting portion that allows crimping between the barrel piece and the bottom of the barrel at the front portion of the crimping permitting portion, and a conductor crimping permitting portion that allows crimping of the conductor exposed portion of the wire tip portion,
With a coating crimping allowable part that allows crimping of the insulation coating of the wire tip,
2. The connection structure according to claim 1, wherein the engaging portion is formed on an inner surface of at least one of a barrel piece and a barrel bottom surface of the inter-barrel press-fitting allowable portion. The connection structure according to claim 1 or 2, wherein the engaging portion is formed continuously on the barrel bottom surface and the pair of barrel pieces. The connection structure according to claim 1, wherein a plurality of the engaging portions are formed. A transition part is integrally formed at the tip of the crimp terminal,
The connection structure according to any one of claims 1 to 4, wherein a drain hole is formed in a bottom portion of the transition portion. The connection structure according to claim 5, wherein the drain hole is formed so that a rear end of the hole edge coincides with a tip of a crimping portion in which the crimping allowable portion is in a crimped state. Forming a barrel overlapped portion in which at least a part of the pair of barrel pieces is overlapped with each other in the crimping portion in which the crimping allowable portion is in a crimped state,
Out of the barrel overlapping part, the barrel piece located outside is set as the outer barrel piece, the barrel piece located inside the outer barrel piece is set as the inner barrel piece,
The connection structure according to any one of claims 1 to 6, wherein an outer end of the outer barrel piece in the barrel overlapping portion is located outward from the center in the width direction of the crimping portion beyond the center in the width direction. The connection structure according to claim 7, wherein an outer end of the outer barrel piece in the barrel overlapping portion is folded back so as to wind the outer end portion of the crimping portion.

Images