JP2003110276A - Simple electromagnetic wave shield structure - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a simple electromagnetic wave shield structure which can obtain satisfactory electromagnetic wave shield performance by tightly being connected to shielding braiding for an electromagnetic wave generated by, specially, a large-current and high-voltage transmission line at low cost with a small number of components. SOLUTION: The braiding 20 which cover an electric conductor 10 can easily and securely be connected directly to an external plate case B of a fitted body, e.g. a motor by inserting a clamping bolt 35 into a bolt hole 24 bored in an overlap part 23 of the braiding 20. An electromagnetic wave which is generated by the electric conductor 10 is absorbed through a shield conduction path consisting of a metallic cover 30, a braiding anchor claw 33, the overlap part 23 of the braiding 20, a metallic collar 42, the clamping bolt 35, the external plate case B, and grounding G.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a simple electromagnetic wave shield structure for connecting a wire / cable or a wire harness to an input / output terminal of a motor mounted in an electric vehicle or an input / output terminal of general electronic equipment.

[0002]

2. Description of the Related Art In recent years, the number of weak electric circuits and electronic circuits in automobiles has been increasing more and more.
As high voltage is advancing, effective and low-cost electromagnetic wave shield measures are required to protect weak electric circuits that are weak against electromagnetic wave noise and prevent detection accuracy of various sensors in electronic circuits from being deteriorated by the influence of electromagnetic wave noise.

FIG. 11 is a side sectional view showing a shielded cable connector described in Japanese Utility Model Publication No. 6-23179 as a conventional example of such an electromagnetic wave shield structure. A plurality of pin terminals 3 are held by a terminal holding retainer 2 provided in a cylindrical metal shell 1. The shielded cable 4 is formed by twisting a plurality of insulated wire cores 5 in which a conductor 5a such as a copper wire is covered with an insulator 5b, and winding a metal braid 6 on the twisted insulated wire cores 5 It is covered with the outermost sheath 7. Each end of the insulated core 5 of the shielded cable 4 is stripped off and the conductor 5a is connected to the pin terminal 3. Further, the sheath 7 of the cable end is peeled off to expose the braid 6, and the braid 6
A cylindrical metal net 8 is covered on the bottom end of the, and a heat shrinkable tube 9 is further covered on the metal net 8. The heat-shrinkable tube 9 is heated to press the metal net 8 from above by the shrinking pressure, and the metal net 8
Are pressed against the outer peripheral surface of the metal shell 1 to be connected to the metal shell 1 via the braid 6 and the metal net 8.
Is electrically connected to each other to absorb and shield electromagnetic waves generated from each insulated wire core 5 of the shielded cable 4.

[0004] For example, in the case of a motor mounted in an electric vehicle, electromagnetic waves generated from a high-current / high-voltage power supply wire or cable connected to its input / output terminals can prevent external equipment from being affected, Effective electromagnetic wave shielding measures are required to prevent the effects of electromagnetic waves.

FIG. 12 shows an example of an electromagnetic wave shield structure in the electric wire connecting portion of such a motor input / output terminal. The outer case B of the motor is made of metal such as aluminum, and the wire lead-in port b ₁ provided in the outer case B
Fix the electrical connector to and connect the electric wire 1 through the electrical connector.
0 is drawn into the inside of the outer case B, and the end of the electric wire 10 is connected to the motor input / output terminal by the terminal fitting 13.
In this case, by grounding the outer case B to earth ground G,
The electromagnetic wave generated from the electric wire 10 is dropped to the ground and absorbed.

The electric wire 10 is made up of a plurality of wires, and is covered with a braid 14 in which conductive metal wires are braided in a tubular shape, and a hem end 14a of the braid 14 is an electromagnetic wave shield terminal member. It is connected to the metal shell 15 in the shape of a ring. In that case, the hem end portion 14a of the braid 14 is pressed against the entire outer circumference of the metal shell 15 by crimping the fixing band 17 by crimping the fixing band 17. The metal shell 15 has the bracket portion 15a and the bolt 1
It is connected to the outer plate case B which is grounded and grounded by the reference numeral 6. That is, the electromagnetic wave generated from the electric wire 10 is transferred to the braid 14 → the metal shell 15 → the bolt 16 → the outer case B.
→ Shielding path is established and absorbed in the order of earth ground G.

[0007]

By the way, as shown in FIG.
1 and the conventional electromagnetic wave shield structure shown in FIG. 12 have the following problems.

First, in the case of the structure shown in FIG. 11, a metal net 8 is provided in order to shield the braid 6 from the metal shell 1 by conducting the shield.
Using such a troublesome connecting member, this metal net 8
Is pressed against the metal shell 1 with the heat shrink tube 9. The number of costly members such as the metal net 8 and the heat shrink tube 9 increases, which is disadvantageous in terms of cost, and the heat shrink force of the heat shrink tube 9 alone pushes the metal net 8 against the metal shell 1. Is insufficient. Therefore, the shield resistance is also unstable and effective electromagnetic wave shielding cannot be performed, and the reliability of the shield conduction from the braid 6 to the metal shell 1 is lacking. In addition, if the heat-shrinkable tube 9 is damaged such as ruptured, the metal net 8 comes off and loses the role of connecting the metal shell 1 and the braid 6 to cause electrical discontinuity, and the original electromagnetic wave is lost. There is a concern that the shield function will be impaired.

Further, in the case of the structure shown in FIG. 12, in order to insert a plurality of electric wires 13 for a shield measure, the momentary metal shell 15 and the fixing band 17 have a large diameter and are disadvantageous in terms of cost. Is. As in the case of the heat-shrinkable tube 9 shown in the conventional structure of FIG. 11, the entire circumference of the tube opening of the hem end 14a of the braid 14 is pressed uniformly and firmly to the outer peripheral surface of the metal shell 15 with the fixing band 17. It is difficult to do so, and uneven contact occurs, and sufficient electromagnetic wave shielding performance cannot be obtained.

From the above, the object of the present invention is particularly
To provide a simple electromagnetic wave shield structure that can obtain a satisfactory electromagnetic wave shield performance by firmly connecting to a braid for shielding an electromagnetic wave generated from a high-voltage distribution line with a small number of parts and securely connecting. It is in.

[0011]

In order to achieve the above object, a simple electromagnetic wave shield structure according to a first aspect of the present invention, as shown in FIG.
The electric wire 10 crimped with is covered from the outside with a braid 20 in which a conductive wire is braided in a tubular shape, and a bolt hole 24 is provided in an overlapping portion 23 in which the braid 20 near the tube opening 22 is doubled. As shown in FIGS. 2 and 3 of the first embodiment and FIGS. 4 and 5 of the second embodiment, a fastening bolt 35 is passed through the bolt hole 24 to fasten the overlapping portion 23 of the braid 20 together with the electrical connector. It is characterized in that it is connected to an attached body B which is grounded and grounded on the device side.

With the above structure, the overlapping portion 23 of the braid 20
It has a structure in which a fastening bolt 35 is inserted into a bolt hole 24 provided in the mounting body B such as an outer plate case of a motor mounted on an electric vehicle together with an electric connector. That is, since the braid 20 can be joined to the motor outer case B by an inexpensive and strong joining means such as bolt fastening, reliable electromagnetic wave shielding performance can be obtained. Also, the electrical connector must be at least the overlap 23 of the braid 20.
Since it is only necessary to locally fasten them together,
The shape is simple and can be miniaturized.

In a simple electromagnetic wave shield structure according to a second aspect of the present invention, as shown in FIGS. 2 and 3 as a first embodiment, the electric connector comprises a metal cover 30 and a resin housing 40, and Body 31 of the cover 30
Is provided with a bolt hole 32 that is a bare hole through which the fastening bolt 35 is passed, and a knitting claw 33 that is erected from the hole edge of the bolt hole 32 and can be bent. The knitting claw 33 is used to overlap the braid 20. Metal cover body 31 by crimping 23
The resin-made housing 40 in a state where it is positioned and held by the
And the fastening bolts 35 are connected to the attached body B.

With the above structure, the metal cover 30 forming the electric connector is provided with the braiding claws 33 so that the overlapping portion 23 of the braid 20 is crimped and held. The initial provisional positioning is performed to facilitate the engagement with the resin housing 40 and the assembling work.

Further, in the simple electromagnetic wave shield structure according to the third aspect, as shown in FIGS. 4 and 5 as the second embodiment, the bracket 36 provided so as to project outward from the side wall of the metal cover body 31. The bolt hole 32 and the knitting claw 33 are formed in the bracket, and the bracket 36 is knitted by the knitting claw 33 to crimp the overlapping portion 23 of the braid 20 to position and hold the bracket, and the fastening bolt 35 holds the attached body. It is characterized by being directly connected to B.

With the above construction, the bracket 36 provided on the metal cover 30 is used as a substitute for the resin housing 40, so that the resin housing 40 is unnecessary and the number of members can be reduced. In this case, the knitting claw 33 provided on the bracket 36 presses and holds the overlapping portion 23 of the braid 20 for temporary positioning, whereby the direct connection property with the mounted body B is further enhanced.

On the other hand, in the simple electromagnetic wave shield structure according to the fourth aspect, as shown in FIG. 6, the conductive wires are thermocompression bonded to each other along the bolt holes 24 provided in the overlapping portion 23 of the braid 20. A ring-shaped shield terminal portion 25 is provided.

With the above structure, in this case, the shield terminal portion 25 is formed by thermocompression bonding along the bolt hole 24 provided in the overlapping portion 23 of the braid 20, thereby forming a mesh around the bolt hole 24. All of the individual wires of are connected to each other in an electrically conductive state, and the braid 20 is metal-bonded to the mounted body B by the fastening bolts 35 by the shield terminal portion 25. The effect of absorbing and dropping to the ground to escape is increased, and an effective electromagnetic wave shielding function can be obtained.

[0019]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a simple electromagnetic wave shield structure according to the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, electric wires / cables and wire harnesses (hereinafter collectively referred to as electric wires 10 for convenience) that have been routed around a vehicle body of an electric vehicle or the like are braided from above over their entire length. It can be protected by being covered with a corrugated tube 20 and covered with a corrugated tube (not shown) at each of the important points of the wiring position from above the braid 20.
In this example, the braid 20 is formed by braiding a conductive metal wire into a tubular shape. However, a resin wire such as polyester is made of Cu (copper).
It is also well known that a spirally wound plated wire is used as a mesh wire and is braided into a tubular shape.
When the tube mouth 22 of the braid 20 is thermocompression-bonded and hardened and shaped, the metal wires in the tube mouth 22 are electrically connected to each other without fraying or loosening. Such shaping of the tube mouth 22 also enhances the efficiency of dimensioning in the wiring work, the connection work to the equipment, and the like.

The electric wire 10 is shown by extruding and covering an insulator 12 on a conductor 11 such as a copper wire. The conductor 12 which is obtained by peeling off the insulator 12 of each terminal is exposed to a terminal fitting such as an LA terminal. 13 is crimped and crimped at the crimped portion 13a. Such electric wire terminals and terminal fittings 13
Is mounted on an outer plate case B made of metal such as aluminum of the mounted motor, and is drawn in from an electric wire drawing port b ₁ (see FIG. 12) provided through the outer case. A bolt (not shown) is fastened to the motor input / output terminal in the bolt hole 13b of the drawn-in terminal fitting 13 so as to establish electrical continuity. At this time, an electromagnetic wave shield treatment is performed on the braid 20 and the following members so that the electromagnetic waves do not affect other devices due to the large current and high voltage flowing through the electric wire 10.

The braid 20 is provided with an overlapping portion 23 so as to double-fold the vicinity of the tube opening 22 in a state where each electric wire 10 is passed through, and a bolt hole 24 is formed therein. The bolt hole 24 is a hole through which the fastening bolt 35 is inserted, and is provided for bolting the braid 20 to the motor outer plate case B (FIGS. 2 and 3) which is grounded and grounded as an attached body. .

2 and 3, the overlapping portion 23 of the braid 20 is screwed together with the electrical connector with the fastening bolt 35 into the female screw hole b ₂ of the motor outer plate case B, and is fastened together.
FIG. 3 is an exploded view and an assembly view showing a first embodiment of a structure for establishing a shield conduction path between the braid 20 and the outer case B.

First, in the first embodiment, in the metal cover 30 constituting the electric connector, the main body 3
In this case, a rectangular bolt hole 32 is formed in an appropriate place on the top plate which is the main portion of the first plate 1, and a pair of opposed knitting claws 33 are provided upright at the edge of the bolt hole 32. Further, a lock hole 34 for fitting and assembling into a resin housing 40, which will be described next, is provided on the side wall of the main body 31.

The resin housing 40, which also constitutes an electrical connector, has a metal collar 42 at a proper position in the main portion of the main body 41.
Is fitted and provided, and the fastening bolt 35 can be inserted into the metal collar 42. As is apparent from the assembly diagram of FIG. 3, the metal collar 42 is in contact with both the overlapping portion 23 of the braid 20 and the outer case B via the fastening bolts 35 to relay the electrical continuity. Is. Therefore, the metal collar 42 can be regarded as a member having an electromagnetic wave shield terminal function. Further, on the side portion of the main body 41, the lock protrusion 4 for fitting and assembling into the lock hole 34 provided in the metal cover 30 is provided.
3 is provided.

As described above, since the metal cover 30 and the resin housing 40 constituting the electric connector may have a size and a shape capable of accommodating at least the overlapping portion 23 of the braid 20, the entire electric connector can be simplified. It has the advantage that it can be miniaturized with a simple shape.

With the above structure, the simple electromagnetic wave shield structure according to the first embodiment has the following function. In FIG. 3, with the terminal metal fitting 13 of the wire end set in the outer plate case B from the wire lead-in port b ₁ (see FIG. 12), the fastening bolt 35 is inserted into the bolt hole 24 of the overlapping portion 23 of the braid 20.
Through, and is screwed into the female screw hole b ₂ of the outer plate case B to be coupled. At that time, in the metal cover 30 of the electrical connector,
The knitting claw 33 is bent, locked in the bolt hole 24 of the overlapping portion 23 of the braid 20 and crimped, and the overlapping portion 23 is temporarily positioned in advance and set. After that, the fastening bolt 35
Are sequentially passed through the bolt holes 32 of the metal cover 30 and the metal collar 42 of the resin housing 40, and screwed into the female screw holes b ₂ of the outer case B. At this time, the braid 20
The overlapping portion 23 contacts the metal collar 42 on the resin housing 40 side.

As a result, the electromagnetic waves generated from the high-current / high-voltage electric wire 10 during energization and use after being mounted on the actual machine are: metal cover 30 → braiding claw 33 → overlapping portion 23 of braid 20 → metal collar 42 → It is absorbed in the shield conduction path of the fastening bolt 35 → the outer case B → the earth ground G.

Next, FIGS. 4 and 5 are an exploded view and an assembly view showing a simplified electromagnetic wave shield structure of the second embodiment according to the present invention which should be called a modification of the first embodiment. The same parts and portions as those shown in the first embodiment are designated by the same reference numerals.

In the second embodiment, the metal cover 30 is used.
The bracket 36 is integrally formed by projecting from the side wall of the braid 20.
Is pressure-bonded to be temporarily positioned and held, and the overlapping portion 23 is directly connected to the main body case B of the motor. That is, the number is reduced without using the resin housing 40 of the first embodiment, which contributes greatly to the cost reduction, and the assembly height and bulk of the electrical connector can be made thin and compact,
It is effective when the installation space is strictly limited such as the vehicle body.

In the metal cover 30, the bracket 3
6 is provided with a bolt hole 37, which is a hole for passing the fastening bolt 35,
A pair of facing knitting claws 38 are formed upright on the hole edge. In addition, knitting claws 39 are provided so as to project also on both sides of the bracket 36. Therefore, the overlapping portion 23 of the braid 20 is bent and held by crimping the knitting claw 38 from the bolt hole 37 side, and the overlapping portion 23 is crimped and held from the outside by bending the knitting claw 39 to hold the overlapping portion 23. The portion 23 can be temporarily positioned on the metal cover 30.

With the above structure, the simple electromagnetic wave shield structure according to the second embodiment operates as follows. In the assembly drawing of FIG. 5, the terminal metal fitting 13 of the wire end is attached to the outer plate case B.
In the state where it is set from the wire lead-in port b ₁ (see FIG. 12), the fastening bolt 35 is passed through the bolt hole 24 of the overlapping portion 23 of the braid 20 and screwed into the female screw hole b ₂ of the outer plate case B to be connected. To do. At this time, in the metal cover 30 of the electric connector, the overlapping portion 23 of the braid 20 is previously bent and crimped by the knitting claws 38 and 39 to the bracket 36, and the bracket 36 is set in the temporary positioning state. After that, the fastening bolts 35 are sequentially passed through the bolt holes 37 of the bracket 36 and the bolt holes 24 of the braid 20 and screwed into the female screw holes b ₂ of the outer plate case B, so that the overlapping portion 23 of the braid 20 is removed. Directly connect to plate case B.

As a result, the electromagnetic waves generated from the high-current / high-voltage electric wire 10 during energization and use after being mounted on the actual machine are such that the metal cover 30 → braiding claws 38, 39 → overlapping portion 2 of the braid 20.
It is absorbed in the shield conduction path of 3 → fastening bolt 35 → outer plate case B → earth ground G.

On the other hand, FIG. 6 shows that all of the conductive wires around the bolt holes 24 are mutually bonded by thermocompression and hardening along the bolt holes 24 in the overlapping portion 23 of the braid 20 shown in FIG. It shows a structure in which a ring-shaped shield terminal portion 25 is formed so as to be electrically connected.

In this way, the periphery of the bolt hole 24 on the side of the braid 20 is formed into the shield terminal portion 25 which is thermocompression bonded, and the shield terminal portion 25 is attached to the outer case B by the fastening bolts 3.
If 5 is metal-bonded, the induced current generated in all of the conductive wires forming the mesh of the braid 20 is absorbed,
The electromagnetic shield effect that drops into the ground and escapes is doubled.

In FIGS. 7 and 8, the shield terminal portion 25 thus formed on the overlapping portion 23 of the braid 20 is tightened together with the metal cover 30 and the electric connector of the resin housing 40 with the fastening bolts 35, and the outside of the motor. Board case B
Is an exploded view and assembled view showing a third embodiment is screwed in the female screw hole b _2. This establishes a shield conduction path between the braid 20 and the outer case B. Metal cover 30 and resin housing 40 that form an electrical connector
2 is the same as that shown in FIGS. 2 and 3 of the first embodiment.

9 and 10 are an exploded view and an assembly view showing a simple electromagnetic wave shield structure of the fourth embodiment, which should be called a modification of the third embodiment. The electrical connector in this case is the same as that shown in FIGS. 4 and 5 of the second embodiment, which is composed of only the metal cover 30.

Therefore, in the third and fourth embodiments described above, the ring-shaped shield terminal portion 25 is formed by solidifying the periphery of the bolt hole 24 on the side of the braid 20 by thermocompression bonding, so that the conductive wire All are in electrical communication with each other. That is, if the shield terminal portion 25 is metal-bonded to the outer case B with the fastening bolts 35, the braid 2
It is possible to effectively absorb the induced current generated in each of the conductive wires forming the 0 mesh.

[0039]

As described above, in the simple electromagnetic wave shield structure according to the first aspect of the present invention, the fastening bolt is passed through the bolt hole provided in the overlapping portion of the braid, for example, the outer plate of the motor mounted in the electric vehicle. Since the braid can be bonded to the motor outer case by an inexpensive and strong connecting means such as a bolt, it is possible to obtain a reliable electromagnetic wave shielding performance. In addition, since the electrical connector only needs to be fastened together with only the overlapping portion of the braid locally accommodated, the electrical connector has a simple shape and can be downsized.

Further, in the simple electromagnetic wave shield structure according to the present invention, the metal cover constituting the housing of the electric connector is provided with the braiding claws so that the overlapping portion of the braid is crimped and held. The initial provisional positioning of the braid with respect to the electrical connector facilitates engagement with the resin housing and assembly work.

Further, in the simple electromagnetic wave shield structure according to the present invention, the bracket provided on the metal cover as an electric connector is used as a substitute for the resin housing, so that the resin housing is not required and the number of members of the electric connector is reduced. Since the braided claws provided on the bracket are pressure-bonded to the overlapping portions of the braid for temporary positioning, the direct connection with the motor outer case, which is the mounted body, is further enhanced.

On the other hand, in the simple electromagnetic wave shield structure according to the fourth aspect, the shield terminal portion is formed by thermocompression bonding along the bolt hole provided in the overlapping portion of the braid,
One of the conductive wires forming the mesh around the bolt holes 1
All the books are electrically connected to each other, and if the braided metal shield is connected to the attached body with a fastening terminal, the effect of absorbing the induced current generated in the entire braid and dropping it to the ground is increased, An effective electromagnetic wave shielding function can be obtained.

[Brief description of drawings]

FIG. 1 is a plan view showing a state in which an electric wire is covered with a braid which is a main part of a simple electromagnetic wave shield structure according to the present invention.

FIG. 2 is an exploded perspective view showing a mode in which the motor outer plate case is fastened together with the electric connector at the overlapping portion of the braid in the first embodiment.

FIG. 3 is an assembled sectional view of the first embodiment.

FIG. 4 is an exploded perspective view showing a mode in which the motor outer plate case is fastened together with the electric connector at the overlapping portion of the braid in the second embodiment.

FIG. 5 is an assembled sectional view of the second embodiment.

FIG. 6 is a plan view showing a state in which an electric wire is covered with a braid, which is a main part of the simple electromagnetic wave shield structure according to the present invention, when the shield terminal is provided.

FIG. 7 is an exploded perspective view showing a mode in which the motor outer plate case is fastened together with the electric connector at the overlapping portion of the braid in the third embodiment.

FIG. 8 is an assembled sectional view of the third embodiment.

FIG. 9 is an exploded perspective view showing a mode in which a motor outer plate case is fastened together with an electric connector at an overlapping portion of a braid in a fourth embodiment.

FIG. 10 is an assembled sectional view of the fourth embodiment.

FIG. 11 is an assembled side sectional view showing an example of a conventional structure relating to an electromagnetic wave shield structure.

FIG. 12 is an assembled side sectional view showing an example of a conventional structure relating to another electromagnetic wave shield structure.

[Explanation of Codes] 10 Electric Wire 11 Conductor 12 Insulator 13 Terminal Bracket 20 Braid 21 Braid Main Body 22 Tube Mouth 23 Overlap 24 Bolt Hole 25 Shield Terminal 30 Metal Cover (Electrical Connector) 32 Bolt Hole 34, 37 Lock Hole 35 Fastening Bolts 36 Brackets 33, 38, 39 Braiding claws 40 Resin housing (electrical connector) 42 Metal collar 43 Lock protrusion B Motor outer plate case (attached body) b ₁ Wire lead-in port b ₂ Bolt screw female Screw hole

Claims (4)

[Claims] 1. An electric wire is covered from the outside with a braid in which a conductive wire is braided in a tubular shape, and a bolt hole is provided in an overlapping portion where the tubular mouth of this braid is doubled and fastened to this bolt hole. A simple electromagnetic wave shield structure characterized in that the overlapping portion is fastened together with an electric connector through a bolt and is coupled to a grounded grounded body on a device side. 2. The electric connector comprises a metal cover and a resin housing, the main body of the metal cover is provided with a bolt hole through which the fastening bolt is passed, and the knitting is erected from the hole edge of the bolt hole and bendable. A claw is provided, and the knitting claw is used to crimp the overlapping portion of the braid to position and hold it on the metal cover main body, and in the state of being clamped together with the resin housing and the fastening bolt, it is coupled to the attached body. The simple electromagnetic wave shield structure according to claim 1, wherein 3. The bracket hole extending outward from the side wall of the metal cover body is formed with the bolt hole and the braiding claw, and the bracket is positioned by crimping the overlapping portion of the braid with the braiding claw. The simple electromagnetic wave shield structure according to claim 2, wherein the fastening bolt is directly connected to the attached body while being held. 4. A ring-shaped shield terminal portion, which is formed by thermocompressing conductive wires to each other, is provided along a bolt hole provided in the overlapping portion of the braid. Simple electromagnetic wave shield structure described in.