JP2017027696A - Water cutoff structure of drain wire of shielded wire - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water stop for a drain wire of a shield wire easily and inexpensively.
A metal cap formed by processing a metal foil or a thin and flexible metal thin plate, a terminal fitting provided with a barrel that is caulked and fixed to an outer peripheral surface of the metal cap, the terminal fitting, and others A batch waterproof rubber sheet provided with a plurality of through-holes closely contacting the outer peripheral surface of the metal cap to be inserted and the outer peripheral surface of another electric wire as a connector for inserting and locking the terminal fittings crimped to the electric wires in the terminal accommodating chambers. It is equipped with an internal connector, and a drain wire composed of a plurality of twisted shield wires is inserted into the metal cap and fixed by crimping with a barrel of the terminal fitting, and the terminal fitting is inserted and locked into the connector. ing.
[Selection] Figure 6

Description

  The present invention relates to a drain wire waterproof structure for a shield wire, and more specifically, a plurality of shield wire drain wires connected to an ECU (electronic control unit) mounted on a vehicle are connected by splice connection to an earth circuit in the ECU. In doing so, it is intended to prevent water from entering the ECU from the drain line side.

  Recently, the number of ECUs mounted on a vehicle has increased, and a shielded wire is often used to transmit a control signal from the ECU to an auxiliary device such as a drive device. In this case, as shown in FIG. 7, the ECU 100 and the auxiliary machine 102 are connected by a wire harness including a plurality of shield wires 105 (105A, 105B). Each shield wire 105 peels off the sheath 106 at the connection terminal between the ECU 100 and the auxiliary machine 102 to expose the core wire (covered electric wire) 108 and the drain wire 109, and the terminal T connected to the terminal of the core wire 108 is connected to the ECU 100 and the auxiliary device 102. It is connected to the connector of the machine 102. On the other hand, the drain wire 109 which is a bare wire not covered with the plurality of shield wires 105 and the core wire 113 on one end side of the general covered electric wire 112 are spliced, and the terminal T connected to the other end of the covered electric wire 112 is connected to the ECU 100. The connector is connected.

  In many cases, the drain wire 109 is formed by twisting a plurality of strands (as a stranded wire) in order to ensure flexibility during wiring. When water is applied to the drain wire composed of the twisted wire, water enters the gaps between the drain wires, and the infiltrated water penetrates in the length direction inside the drain wire. In order to prevent permeation of water in the drain wire, the splice between the drain wire 109 and the core wire 113 of the covered electric wire 112 is performed by crimping or welding using an intermediate crimping terminal. Furthermore, butyl tape and adhesive tape are wound around the crimped or crimped or welded splice with this terminal, or the splice is inserted into a resin water-stop cap and filled with a water-stopper, or resin-molded. The water is stopped.

  The present applicant has disclosed a patent No. 5188713 as a water stop structure of one drain wire exposed from one shield wire, not a water stop of a ground wire formed by splicing a plurality of drain wires of shield wires. A terminal in which a drain wire exposed at the end of a shielded wire is covered with a heat-shrinkable tube, filled with a water-stopping agent in the heat-shrinkable tube, and thermally contracted, and crimped at the end of the drain wire And a water-stop structure for covering the boundary between the heat-shrinkable tube with a rubber stopper.

Japanese Patent No. 5188713

  When the water-stopping structure shown in FIG. 7 is used and a butyl tape or an adhesive tape is wound around the splice portion where the drain wire and the core wire of the ground wire are connected, the water-stopping reliability is poor if the tape winding accuracy is low. Further, when the splice portion is inserted into the resin water-stop cap and filled with the water-stopping agent, there are problems that it takes time to fill the water-stopper and takes time to cure the water-stopper. In addition, in the case of resin molding, there is a problem that a mold and a molding facility are required and the cost is increased.

  In the water stop structure of one drain wire of Patent Document 1, a heat shrinkable tube is required and the tube needs to be filled with a water stop agent. Therefore, there is a problem that the parts cost is high and the work time is long. In addition, there is a possibility that the water-stopping agent may adhere to the terminal and cause poor conduction, and the water-stopping agent in the tube will harden, increasing the rigidity of the wire, making it difficult to wire, and room for improvement. There is. In particular, when a plurality of drain wires are connected by splice, there is a problem that cannot be adopted.

  The present invention has been made in view of the above problems, and when the drain wires drawn out at the terminals of the plurality of shielded wires are spliced and connected to the ground circuit of the ECU, the drain wire side is immersed in the ECU. An object of the present invention is to provide a drain wire waterproof structure for a shielded wire that can be surely prevented and that can reduce cost and working time.

In order to solve the above problems, the present invention provides:
A metal cap formed by processing a metal foil or a thin metal plate that is thin and flexible; and
A terminal fitting provided with a barrel for crimping and crimping to the outer peripheral surface of the metal cap;
As the connectors for inserting and locking the terminal fittings to be crimped to the metal cap and the terminal fittings to be crimped to other electric wires into the terminal receiving chambers, a plurality of the metal fittings closely contacting the outer circumferential surface of the metal cap to be inserted and the outer circumferential surface of the other electric wires. Equipped with a waterproof connector with a built-in batch waterproof rubber sheet with through-holes,
A drain wire of a shield wire in which a drain wire composed of a plurality of shield wires is inserted into the metal cap and crimped with a barrel of the terminal fitting, and the terminal fitting is inserted and locked into the waterproof connector. Provides a water stop structure.

  As described above, a stranded drain wire exposed by peeling off the sheath at the end of the shield wire is inserted into the metal cap, and the drain wires of the plurality of shield wires are brought into contact with each other in the metal cap and spliced. The drain wire splice portion is inserted into the metal cap that functions as a water stop cap to simultaneously achieve water stop and conduction between the drain wires. Moreover, since the terminal fitting to be crimped and crimped to the metal cap is inserted and locked to the waterproof connector, the metal cap in the waterproof connector can be prevented from being immersed in the drain wire, and the waterproof connector is fitted. It is possible to reliably prevent the occurrence of water in the electrical component.

  It is preferable that the waterproof connector connected to the terminals of the plurality of shielded wires is fitted into a connector fitting portion provided in an electronic control unit (ECU) mounted in the engine room in the flooded area. In addition, the electrical component of the other party part which fits this waterproof connector is not limited to ECU, It can use also for electrical connection boxes other than ECU.

An electronic control unit (ECU) is used as an electrical junction box connected to the shielded wire, and the ECU is preferably used when mounted in an engine room in a flooded area.
A signal line connected to a sensor or the like is connected to the ECU, and a shield line is preferably used as the signal line. The shield wire is wired by bringing a drain wire into contact with a shield material made of a metal braided wire or a metal foil surrounding the core wire, and as shown in the conventional example of FIG. In order to connect to the ground circuit, the drain wire of multiple shield wires is spliced to form one ground wire and connected to one connector together with the core wire, and the connector is fitted to the connector fitting part of the ECU doing. In this configuration, in order to prevent water from entering the ECU through a drain wire connected to the ground circuit in the ECU, the present invention includes a metal cap, a terminal fitting that is crimped to the metal cap, In order to prevent water from entering the ECU, a waterproof connector in which a terminal fitting with a metal cap crimped is inserted in a water-stopped state is used.

If it is the structure of the said invention, in order to stop water of the drain wire of a shield wire, the water stop agent and heat-shrinkable tube which are required in patent document 1 can be made unnecessary, and the terminal of the terminal of this drain wire It is possible to save the work of attaching a waterproof rubber plug to the boundary.
Note that the drain line penetrating through the shield wire and located on the other end side (the side opposite to the ECU connection side) may be cut off and separated, or the vehicle body panel may be grounded.

The metal cap is formed by pressing the metal foil or the metal thin plate to close one end and make the other end cylindrical with an opening, and has an inner diameter that contacts the outer periphery of a plurality of drain wires to be inserted inside. It is preferable to provide a trumpet-shaped insertion portion that expands in diameter at the periphery of the opening.
In particular, it is preferable that the metal cap is formed of a metal having good conductivity and an ionization tendency with the metal material of the terminal fitting and the drain wire, for example, copper foil or aluminum foil. The metal foil or metal sheet used as the metal cap preferably has a thickness of 0.2 to 0.4 mm and an outer diameter of 1.2 to 2.0φ.

The terminal fitting for caulking and fixing a pair of barrels to the metal cap with the drain wire inserted is formed by stamping a copper-based metal plate and then pressing it.
Specifically, the terminal fitting made of a copper-based metal plate is provided with a female terminal portion or a male terminal portion as an electrical contact portion on one side of a rectangular substrate, and is crimped and crimped to the metal cap on the other side of the substrate. A pair of barrels projecting from both ends of the substrate in the width direction are set so that the tips of the barrels are joined to each other in a state of crimping and crimping to the metal cap so as to form an annular cross section.

  That is, the barrel provided on the terminal fitting for crimping the metal cap is normally set so that the tip of the barrel protrudes toward the inner peripheral side and bites into the core wire to be swaged. In the present invention, the tip of the barrel is strong against the metal cap. If pressed, the metal cap may be damaged, so that the barrel tip does not protrude inwardly sticking into the metal cap during crimping.

  As described above, in the drain wire waterproof structure of the shield wire of the present invention, the drain wires of the plurality of shield wires to be spliced are inserted into the metal cap, and the metal cap for inserting the plurality of drain wires is inserted into the terminal fitting. Clamping and crimping with a barrel, splice connection between multiple drain wires inside the metal cap, and the splice-connected drain wire, metal cap and terminal fitting are fixed together, and the terminal fitting is attached with a waterproof rubber sheet It is waterproofed in a lump and inserted and locked to the connector. As described above, since the water is stopped without using the water-stopping agent, the working time can be shortened, and the cost can be reduced by not using the heat-shrinkable tube.

  In addition, it is possible to block the drainage of the drain wire made of stranded wire, which is likely to be flooded, inside the metal cap, and to conduct the splice connection portion of the drain wire to the terminal fitting through the metal cap, and insert and lock the terminal fitting. By connecting to the ECU via the waterproof connector, it is possible to conduct in a state in which water is reliably blocked from the ground circuit in the ECU. As a result, it is possible to reliably eliminate the occurrence of corrosion due to water immersion in the ECU and to improve electrical connection reliability.

1 is an overall configuration diagram showing an embodiment of the present invention. (A) is sectional drawing of a shield wire, (B) is a front view which shows the connection state of the core wire of a shield wire, and a terminal metal fitting. The metal cap used by this invention is shown, (A) is a front view of a metal cap, (B) is the left view of (A), (C) is the state which has spliced several drain wires in the metal cap It is drawing which shows. The terminal metal fitting which crimps and crimps | bonds to the said metal cap is shown, (A) is a perspective view, (B) is a front view. The crimping | compression-bonding state of the said drain wire and a terminal metal fitting is shown, (A) is a front view, (B) is a BB sectional drawing of (A). (A) is a partial cross-sectional view of a connector for inserting and locking the terminal fitting, (B) is a perspective view of a waterproof rubber sheet mounted in the connector, and (C) is an enlarged view of a main part of (A). . It is the schematic which shows a prior art example.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In the embodiment, a drain wire 4 of a plurality of shield wires 3 (3A, 3B) connected to an electronic control unit 2 (hereinafter abbreviated as ECU) mounted in an engine room that is a flooded area of a vehicle and an auxiliary machine 50. (4A, 4B) is stopped and water is prevented from flowing through the drain wire 4 inside the ECU 2.

The shield wire 3A connected to the ECU 2 has one core wire 5, and as shown in FIG. 2 (A), the drain wire 4 (4A) and the core wire 5 are made of a metal braided wire or a metal foil tape. The shield material 6 is surrounded by a shield material 6 and covered with a sheath (outer skin) 7 made of an insulating resin. The core wire 5 is a round electric wire in which the core wire 5a is covered with an insulating coating 5b, and the drain wire 4 is a stranded wire of a plurality of strands and is a bare wire without an insulating coating.
The shield wire 3B connected to the ECU 2 has two core wires 5, and the two core wires 5 and one drain wire 4B are surrounded by a shield material 6 and covered with a sheath 7.

  The shield wires 3A and 3B are peeled off the sheath 7 and the shield material 6 on the terminal side connected to the ECU 2 to expose the core wire 5 and the drain wires 4 (4A, 4B), as shown in FIG. The core wire 5 is further stripped of the insulation coating 5b on the terminal side to expose the core wire 5a, and the terminal fitting 8 is crimped and crimped as shown in FIG. The terminal fitting 8 is a female terminal made of a general-purpose copper-based metal, and has a female terminal portion 8a on one side of the substrate 8b, and is crimped to the core wire barrel 8c and the insulation coating 5b that are crimped to the core wire 5a on the other side of the substrate. A coating barrel 8d is provided.

  The drain wire 4A of the shield wire 3A and the drain wire 4B of the shield wire 3B are each composed of a large number of strands of strands, and are inserted into the metal cap 1 made of the metal foil shown in FIG. Are crimped with a pair of barrels 11c of the terminal fitting 11 shown in FIG. The terminal fitting 11 is a female terminal made of a copper-based metal similar to the terminal fitting 8 connected to the core wire 5, and is provided with a female terminal portion 11b on one side of the rectangular substrate 11a and in the width direction on the other side of the substrate 11a. A pair of barrels 11c that are crimped and crimped to the metal cap 1 from both sides are provided so as to face each other.

  The terminal fitting 11 for connecting the drain wires 4A and 4B via the metal cap 1 and the terminal fitting 8 for connecting with the core wire 5 are inserted and locked to the connector 10 as shown in FIGS. The connector 10 is fitted to a connector fitting portion 2a provided in the ECU 2, and is fitted and connected to a male terminal (not shown) connected to a circuit in the ECU 2. The drain wires 4A and 4B are connected to the ground circuit 22 in the ECU 2 through the metal cap 1 and the terminal fitting 11, and are connected through the connector 10 to the ground wire 13 for grounding the ground circuit 22 to the vehicle body panel or the like.

  The metal cap 1 into which the drain wires 4A and 4B to be spliced are inserted is formed by pressing a copper-based metal foil made of the same material as the drain wire, and as shown in FIG. 3, one end of the cylindrical portion 1a is made into a closed portion 1b. In addition, a trumpet-shaped insertion portion 1c having an opening at the other end and expanding in diameter at the periphery of the opening is provided. The cylindrical part 1a is set to the magnitude | size which has an internal diameter which contacts the outer periphery of the strand wire of several drain wire 4A, 4B inserted in an inside. The metal cap 1 of this embodiment has a thickness of 0.3 mm, an outer diameter of 1.6φ, and an inner diameter of 1.0φ.

  As shown in FIG. 5, the pair of barrels 11 c of the terminal fitting 11 that crimps and crimps the intermediate portion of the cylindrical portion 1 a of the metal cap 1 into which the drain wires 4 </ b> A and 4 </ b> B are inserted is crimped. The ends of the barrels 11c and 11c are joined to each other in a crimped state to form an annular cross section, and the outer peripheral surface of the metal cap 1 is set to be crimped and crimped by the barrels 11c and 11c.

  By crimping and crimping the metal cap 1 with the barrels 11c and 11c of the terminal fitting 11, the outer peripheral wall of the cylindrical portion 1a of the metal cap 1 made of metal foil is compressed and deformed in the inner diameter direction, and the internal drain wire 4A, The 4B strands are brought into close contact with each other, and the inner peripheral surface of the metal cap 1 is brought into close contact with the drain wires 4A and 4B. As a result, the three members of the two drain wires 4A and 4B, the metal cap 1 and the terminal fitting 11 are fixed together. In addition, the splices of the drain wires 4A and 4B and the splice can be conducted to the terminal fitting 11 via the metal cap 1 and can be conducted to the ground circuit in the ECU 2 via the terminal fitting 11.

  As shown in FIG. 6, the connector 10 for inserting and locking the terminal fitting 11 connected to the drain wires 4A and 4B and the terminal fitting 8 connected to the core wire 5 is separated by a partition wall 10a provided in the connector housing. A plurality of terminal accommodating chambers 10b into which terminal fittings are respectively inserted are provided. In the connector 10, a collective waterproof rubber sheet 12 shown in FIG. 6B is attached through an attachment hole 11h provided in the upper wall of the connector housing and the partition wall 10a. The collective waterproof rubber sheet 12 is provided with four through-holes 12a located in each terminal accommodating chamber 10b in parallel in the vertical direction.

  With the collective waterproof rubber sheet 12 mounted inside the connector housing, the outer surface of the collective waterproof rubber sheet 12 is in close contact with the inner peripheral surface of the terminal accommodating chamber 10b at a position close to the terminal insertion side opening 10c of each terminal accommodating chamber 10b. In addition, water intrusion into the terminal accommodating chamber 10b communicating with the insertion side opening 10d of the counterpart terminal is blocked.

  The inner peripheral surface of the through hole 12a of the collective waterproof rubber sheet 12 disposed in each terminal accommodating chamber 10b is sized to be in close contact with the outer peripheral surface of the core wire 5 and the outer peripheral surface of the metal cap 1, as shown in FIG. There are four on the top and bottom. That is, the outer diameter of the metal cap 1 is made equal to the outer diameter of the core wire 5, and the outer peripheral surface of the metal cap 1 together with the core wire 5 is in close contact with the inner peripheral surface of the through hole 12 a.

  Since the connector 10 is a waterproof connector in which the batch waterproof rubber sheet 12 is attached, there is no need to attach a rubber plug to each of the wires inserted into the connector 10, and the number of rubber plugs attached to each wire can be saved. Can do.

  In the drain wire waterproof structure of the shield wire of the present invention, the core wire 5 of the shield wires 3A and 3B to the ECU 2 is connected to the signal circuit and the power circuit in the ECU 2 as described above. On the other hand, the drain wires 4A and 4B of the shield wires 3A and 3B are spliced inside the metal cap 1, the metal cap 1 is crimped to the terminal fitting 11, and the terminal fitting 11 is connected to the ground circuit 22 in the ECU 2. Yes.

  At that time, since the core wire 5 is covered with the insulating coating 5b, the core wire 5 is inserted into and locked to the connector 10 provided with the batch waterproof rubber sheet 12, so that the water entering the ECU 2 transmitted through the core wire 5 is prevented. Can be prevented.

  On the other hand, since the drain wires 4A and 4B to which the shield wires 3A and 3B are spliced are bare wires without insulation coating and are twisted wires, water is likely to be generated in the gaps between the drain wires 4A and 4B. . The drain wires 4A and 4B are inserted into the metal cap 1 to prevent water from entering, and the drain wires 4A and 4B are brought into contact with each other in the metal cap 1 to form a splice portion. By inserting the splices of the drain wires 4A and 4B into the metal cap 1 that functions as a water stop cap, the water stop and the metal cap 1 are connected to each other at the same time. In addition, since the terminal metal fitting 11 that is caulked and fixed to the metal cap 1 is inserted and locked into the connector 10 having a built-in waterproof rubber sheet 12 and having a waterproof function, the connector 10 is transmitted through the drain wires 4A and 4B. It is possible to reliably prevent water from entering the ECU 2 via

  In particular, according to the present invention, as in Patent Document 1, in order to stop the drain wire of the shield wire, a water stop agent and a heat-shrinkable tube can be unnecessary, and the terminal of the drain wire and It is possible to save the work of attaching a waterproof rubber stopper to the boundary. As a result, it is possible to significantly reduce the work time required for water stop and reduce the cost.

  The present invention is not limited to the above-described embodiment, and the drain wire of the shield wire may be a metal braided wire used as a shield material drawn out and twisted into one. It may be inserted into and spliced. Further, the drain wire of three or more shield wires may be spliced in the metal cap.

1 Metal cap 2 ECU
3 (3A, 3B) Shielded wire 4 (4A, 4B) Drain wire 5 Core wire 10 Connector 11 Terminal fitting 11c Barrel 12 Collective waterproof rubber sheet 50 Auxiliary machine

Claims (4)

A metal cap formed by processing a metal foil or a thin metal plate that is thin and flexible; and
A terminal fitting provided with a barrel for crimping and crimping to the outer peripheral surface of the metal cap;
As the connectors for inserting and locking the terminal fittings to be crimped to the metal cap and the terminal fittings to be crimped to other electric wires into the terminal receiving chambers, a plurality of the metal fittings closely contacting the outer circumferential surface of the metal cap to be inserted and the outer circumferential surface of the other electric wires. Equipped with a waterproof connector with a built-in batch waterproof rubber sheet with through-holes,
A drain wire of a shield wire in which a drain wire composed of a plurality of shield wires is inserted into the metal cap and crimped with a barrel of the terminal fitting, and the terminal fitting is inserted and locked into the waterproof connector. Water stop structure.   2. The drain wire waterproof structure for a shield wire according to claim 1, wherein the connector is fitted into a connector fitting portion provided in an ECU mounted in an engine room in a flooded area.   The metal cap is formed by pressing the metal foil or the metal thin plate so that one end is closed and the other end is a cylindrical shape, and has an inner diameter that contacts an outer periphery of a plurality of drain wires inserted therein. The drain wire waterproof structure for a shield wire according to claim 1 or 2, wherein a trumpet-shaped insertion portion that is enlarged and has a diameter increased at the periphery of the opening.   The terminal fitting for crimping and crimping to the metal cap is provided with a female terminal portion or a male terminal portion as an electrical contact portion on one side of a rectangular substrate made of a conductive metal plate, and the other side of the substrate A pair of barrels projecting from both ends in the width direction of the substrate, and the ends of the pair of barrels are joined to each other in a state of crimping and crimping to the metal cap to form an annular cross section. The drain wire waterproof structure of the shield wire according to any one of claims 1 to 3.

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