JP3230980B2 - Wire shield structure - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield structure of an electric wire constructed so as to obtain the same electromagnetic shield (hereinafter simply referred to as "shield") effect without using a shield wire, as in the case of using a shield wire. In particular, the present invention relates to a shield structure of an electric wire which is suitable for use in a device requiring a reliable shielding performance, such as a control device mounted on an automobile, and requiring a reduction in cost and an improvement in maintainability.

[0002]

2. Description of the Related Art Various types of electronic equipment including a CPU are mounted on a current automobile, and a shielded wire is used for transmitting and receiving a high-frequency signal. However, the shield wire is expensive, and when wiring, the ground wire of the shield braided wire is required together with the wiring of the core wire, so that the wiring work is troublesome. From such a viewpoint, a wire shield structure has been adopted in which wiring is performed using a normal wire and the wire is shielded to obtain the same shielding effect as when a shield wire is used. An example of the shield structure of the electric wire will be described with reference to FIGS.

[0003] First, the mode of use of the electric wire shield structure 41 will be described. As shown in FIG. 7, the electric shield structure 41 is used to connect electronic equipment such as a CPU and a motor housed in a box 42 with electric wires 45. The electric wire 45 is not a shielded wire, but is shielded by the electric wire shield structure 41 and the corrugated tube 46. Although the shield structure 41 of the electric wire is not a kind as shown by different appearances on the left and right of FIG. 7, an example of the configuration of the shield structure 41 of the electric wire shown on the right side of FIG. 7 will be described with reference to FIGS. I will explain.

An electric wire shield structure 41 includes a box 42 containing electronic equipment such as a CPU, a coupler 44 fixed to a side surface of the box 42 by screws 43, and an electric wire 45.
A corrugated tube 46 for covering the corrugated tube and a corrugated retainer 47 for locking the corrugated tube 46 to the coupler 44.
It is composed of

As shown in FIG. 9, the coupler 44 comprises a flange portion 51 and a tubular portion 52. The tubular portion 52 has a fitting portion 52a fitted into the box 42 and a portion projecting out of the box 42. And divided into A locking groove 53 for locking the corrugated retainer 47 and a locking groove 54 for locking the corrugated tube 46 are formed in a portion protruding outside the box 42.

[0006] As shown in FIG.
Are two half-split members 47a and 47b formed in a gutter shape.
And locked by a locking portion 55 to form a cylindrical shape. At one end of the corrugated retainer 47, an annular locking projection 56 is provided.
When it is assembled to the device, it is locked in the locking groove 53. On the inner surface of the other end of the corrugated retainer 47, a locking projection 57 that locks with the locking groove 54 is formed as shown on the right side of FIG.

Next, the procedure for assembling the electric wire shield structure 41 will be described. First, as shown in FIG. 8, the fitting portion 5 of the coupler 44 is inserted into the mounting opening 42a formed in the box 42.
2a is inserted and tightened and fixed by the mounting screw 43. At this time, as shown in FIG. 8, an annular waterproof packing 62 made of a rubber material or the like is fitted in an annular groove 61 formed in the fitting portion 52a.
The waterproof packing 62 is attached to the
The inside of the box 42 is made watertight by contacting the opening edge of a.

As shown in FIG. 8, one end of a corrugated tube 46 covering the electric wire 45 is covered by a locking groove 54 formed in the cylindrical portion 52, and an end of the electric wire 45 connected to the crimp terminal 45a. Is positioned in box 42.
Then, the half-split member 47 is covered so as to cover the cylindrical portion 52.
a and 47b are covered and inseparably locked by the locking part 55, and the cylindrical corrugated retainer 47 is assembled so as to cover the entire cylindrical part 52 shown in FIG. In this state, the locking projection 56 is locked in the locking groove 53, so that the corrugated retainer 47 cannot be pulled out.

The coupler 44 and the corrugated retainer 47
Is molded of a synthetic resin, but the entire surface is plated with metal. The corrugated tube 46 is also formed into a cylindrical body having flexibility using synthetic resin, and the surface thereof is plated with metal. Therefore, the corrugated tube 46, the corrugated retainer 47, and the coupler 4 are locked by the corrugated tube 46 being locked in the locking groove 54 and being tightened by covering the corrugated retainer 47.
4. The box 42 is electrically connected, and the electric wire 45 is shielded.

[0010]

Although the corrugated tube 46 is integrally formed of a synthetic resin, dimensional variations are likely to occur at the time of finishing. Corrugated retainer 4
Since the corrugated tube 7 presses the corrugated tube 46 from the outside, if the dimensional variation of the corrugated tube 46 always shows a large diameter, there is little danger of a poor contact with the corrugated tube 47. However, the dimensional variation is literally a variation and may appear on a small diameter. In such a case, the corrugated tube 46 and the corrugated retainer 47 have poor contact, and the shielding action becomes unstable.

If the shielding effect of the electric wire 45 becomes unstable, a noise component is superimposed on the electric wire 45, or noise is generated when the power supply of the electric wire 45 is interrupted, which adversely affects other control devices. If the shield structure 41 of the electric wire is applied to, for example, driving control of an automobile, it causes a poor driving control of the automobile. In addition, even when the vehicle is in contact with the vehicle in a stationary state, inconvenience such as poor contact due to the running of the automobile is likely to occur.

An object of the present invention is to provide a shield structure of an electric wire configured to exert a shielding effect without using a shielded wire and to reliably shield an electric wire regardless of dimensional variations of a corrugated tube performing a shielding action. Is to do.

[0013]

SUMMARY OF THE INVENTION The object of the present invention is to provide a corrugated tube which covers an electric wire and has a conductive plating on a surface thereof, the above-mentioned corrugated tube is locked at one end, and the electric wire is inserted inside the corrugated tube. In a shield structure of an electric wire provided with a coupler having a conductive plated surface and a corrugated retainer having a conductive plated surface for connecting the corrugated tube to the coupler, the tubular shape is provided in combination. This is achieved by an electric wire shield structure comprising: a half-split member constituting a corrugated retainer; and a rib formed substantially in an elliptical shape by a combination of the half-split members and engaged with the corrugate tube. can do.

According to the above-described shield structure of the electric wire, the rib is formed into an elliptical shape by combining the half-split members.
Therefore, even if the diameter of the corrugated tube is reduced, the corrugated tube can be locked by the small-diameter portion of the rib, and a defective shield can be prevented.

[0015]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a perspective view showing an embodiment of a shield structure of an electric wire to which the present invention is applied. 1 is a perspective view showing a configuration of a shield structure of an electric wire of the present invention, FIG. 2 is a front view showing a configuration of a corrugated retainer, FIG. 3 is a perspective view showing an external shape of the corrugated retainer, and FIGS. FIG. 6 is an enlarged cross-sectional view of a main part showing the shield structure, showing the locking of the corrugated tube.

An electric wire shield structure (hereinafter simply referred to as a shield structure) 1 according to the present embodiment has the same function as the case where a shielded wire is used without using a shielded wire, that is, when transmitting a high-frequency signal. To prevent oscillation,
It exerts a shielding effect such as preventing the influence of noise. As shown in FIGS. 1, 4 and 5, the shield structure 1 includes a flange 3 fixed to a box 2 containing, for example, a CPU, and a coupler 4 removably fitted to the flange 3. And a corrugated retainer 6 for fixing the corrugated tube 5 to the coupler 4 in a press-contact state, and shields an electric wire 7 wired in the box 2.

The flange portion 3 is formed by integrally molding a synthetic resin, and the entire surface thereof is subjected to conductive plating. The planar shape of the flange portion 3 is formed substantially in the shape of a rhombus,
A screw insertion hole 3a for screwing to the box 2 is formed. A cylindrical portion (not shown) for fitting the coupler 4 is formed at the center of the flange portion 3.
Further, a fixed locking portion 11 for locking the coupler 4 is provided so as to protrude forward from the side surface. Although the flange portion 3 may be a part of the coupler 4, it is separated in the present embodiment for convenience of explanation.

The coupler 4 is formed by integrally molding a synthetic resin, and the entire surface thereof is subjected to conductive plating.
The coupler 4 has a large-diameter first fitting portion 4a fitted so as to cover the cylindrical portion provided on the flange portion 3, and a small-diameter second fitting portion for locking a corrugated retainer 6 described later. And a movable locking portion 12 that locks to the locking portion 11 on an outer peripheral portion of the first fitting portion 4a. The second fitting portion 4b has a cylindrical shape, and a partition 13 is provided therein as shown in FIGS. 4 and 5, and the rubber stopper 14 is positioned by the partition 13. 4 corresponds to a vertical sectional view of the shield structure 1, and FIG. 5 corresponds to a horizontal sectional view of a central portion of the shield structure 1.

An electric wire insertion hole 15 is formed in the rubber stopper 14, and is pressed against the surface of the electric wire 7 inserted through the electric wire insertion hole 15 to prevent infiltration of moisture. The rubber plug 14 is inserted from the open end of the second fitting portion 4b, that is, from left to right in FIGS. 4 and 5, and is positioned while being pressed against the partition wall 13. Further, two locking grooves 16a and 16b for locking the corrugated retainer 6 are formed around the outer periphery of the second fitting portion 4b.

Next, the corrugated retainer 6 will be described. The corrugated retainer 6 is formed by combining gutter-shaped half-split members 6a and 6b as shown in FIG. The half members 6a and 6b are formed by integrally molding a synthetic resin, and the entire surface is subjected to conductive plating. Since the half-split members 6a and 6b have the same structure, they will be denoted by the same reference numerals and described. A large-diameter portion 21a fitted to the second fitting portion 4b and a small-diameter And an engagement portion 21b.

Inside the small-diameter portion 21b, semicircular ribs 22a, 22a from the tip end toward the large-diameter portion 21a are provided.
b and 22c are formed at predetermined intervals. The rib 22
As shown in FIGS. 4 to 6, a and 22b are engaged with locking grooves 5a of the corrugated tube 5 to prevent the corrugated tube 5 from coming out. Ribs 22c are positioned by bringing the ends of the corrugated tube 5 into contact. Is what you do. In addition, the large-diameter portion 21
The ribs 23a and 23b formed on the a are locked in the locking grooves 16a and 16b formed outside the second fitting portion 4b so that the corrugated retainer 6 cannot be pulled out.

At both outer ends of the half members 6a and 6b,
A locking claw 25a for forming one cylindrical body by combination and a locking portion 25b for locking the locking claw 25a are provided. A locking projection 26 is provided at an end of the large diameter portion 21a. When the corrugated retainer 6 is assembled to the coupler 4, the retaining projection 26 is retained by a retaining groove 4 c radially formed on the outer surface of the first fitting portion 4 a so as to rotate the corrugated retainer 6. This is to prevent movement.

Next, the assembly of the shield structure 1 will be described. At the time of this assembling, first, the end of the flange portion 3 is inserted into the fitting opening 2a formed in the box 2, and FIG.
As shown in (2), the O-ring 27 is pressed against the fitting opening 2a to make the inside of the box 2 watertight. Next, the coupler 4 is fitted and locked to the flange portion 3. This operation is performed simply by applying the coupler 4 to the flange portion 3 and pushing it in, so that the operation can be performed as easily as almost one-touch operation. An O-ring (not shown) is also interposed between the flange portion 3 and the coupler 4 to prevent the infiltration of moisture into the coupler 4. At this time, the locking claw 12a constituting the movable locking portion 12 bends and deforms downward in FIGS.
Then, it returns upward due to its own elasticity, and is fixed.
To lock. As a result, the box 2, the flange portion 3, and the coupler 4 are integrated as shown by a solid line in FIG.

Next, the electric wire 7 is inserted through the flange portion 3 and the coupler 4, and the corrugated tube 5 covered on the electric wire 7 is formed.
The half-split members 6a and 6b are placed so as to sandwich the end of the second fitting portion 4b. And each half member 6a,
The locking projection 26 formed on the 6b is aligned with the locking groove 4c, and the locking claw 25a is locked with the locking portion 25b to be integrated, and assembled as a tubular corrugated retainer 6. As a result, the entire electric wire 7 is shielded, but in the present embodiment, the following remarkable functions are performed by the corrugated retainer 6.

That is, the ribs 22a formed at the ends of the half-split members 6a and 6b do not have a shape obtained by dividing a perfect circle into two as shown in the enlarged view of FIG. ing. Therefore, when the half members 6a and 6b are combined, a portion having a large diameter and a portion having a small diameter appear, and the rib 22a has an elliptical shape. Incidentally, in the present embodiment, the outer dimension A of the corrugated retainer 6 is 3
Although it is a perfect circle of about 0.70 mm, the horizontal inner diameter of the rib 22a is about 24.30 mm, and the vertical inner diameter of the rib 22a is about 26.70 mm. In addition, the said dimension is an example to the last, The corrugated tube 5
Are appropriately changed according to the size of the wire 7 and the thickness and the number of the wires 7.

By forming the inner diameter of the rib 22a into an ellipse in this way, even if the corrugated tube 5 becomes smaller due to dimensional variations, for example, the small diameter portion of the rib 22a is engaged as shown in an enlarged view in FIG. It comes into close contact with the stop groove 5a. As a result, the conductivity between the corrugated tube 5 and the corrugated retainer 6 is not impaired, and the contact area is increased, so that the contact resistance is reduced and the shielding effect is ensured. If the dimensions of the corrugated tube 5 vary to a large diameter, the corrugated tube 5 is deformed into an elliptical shape, so that wrinkles and the like are not formed, and there is an advantage that the locking operation is easily performed. For this reason, even when the present invention is applied to, for example, an automobile which vibrates or shakes a lot, the shield of the electric wire 7 is reliably performed, and it is possible to prevent a problem that hinders traveling.

The corrugated retainer 6 has a locking projection 2.
6 are formed, and the rotation of the corrugated retainer 6 can be prevented. Accordingly, the contact between the corrugated tube 5 and the corrugated retainer 6 and the contact between the corrugated retainer 6 and the coupler 4 are improved, and together, the shielding effect of the electric wire 7 can be further ensured.

[0028]

As described above, in the electric wire shield structure according to the present invention, an elliptical rib is formed at one end of a corrugated retainer whose surface has been subjected to a conductive treatment, and the rib is provided on the surface with the conductive treatment. The corrugated tube is locked in the locking groove of the corrugated tube so that the contact between the corrugated tube and the corrugated retainer can be maintained well regardless of the dimensional variation of the corrugated tube. Therefore, the electric wire wired in the corrugated tube is reliably shielded, and not only the bad contact between the corrugated retainer and the corrugated tube but also the poor shielding caused by this poor contact can be prevented. As a result, when this shield structure is applied to, for example, an automobile or the like, malfunction or control failure due to noise can be prevented, and the reliability of various devices and electronic devices such as an automobile can be greatly improved.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of an electric wire shield structure of the present invention.

FIG. 2 is a front view showing a shape of a corrugated retainer.

FIG. 3 is an exploded perspective view showing a configuration of a corrugated retainer.

FIG. 4 is a longitudinal sectional view showing a configuration of a shield structure.

FIG. 5 is a horizontal sectional view showing a configuration of a shield structure.

FIG. 6 is an enlarged sectional view showing a locked state of a rib and a locking groove.

FIG. 7 is a schematic connection diagram showing an application example of a conventional shield structure.

FIG. 8 is a cross-sectional view showing a configuration of a conventional shield structure.

FIG. 9 is a perspective view showing an assembled state of the coupler in FIG. 8;

FIG. 10 is a perspective view showing a configuration of a corrugated retainer in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Shield structure of electric wire 2 Box 3 Flange part 4 Coupler 5 Corrugated tube 6 Corrugated retainer 6a, 6b Half-split member 7 Electric wire 11 Fixed locking part 12 Movable locking part 13 Partition wall 14 Rubber wire 15 Wire insertion hole 16a, 16b Lock Groove 21a Large diameter portion 21b Small diameter portion 22a, 22b, 22c, 23a, 23b Rib 25a Locking claw 25b Locking portion 26 Locking protrusion 270 Ring A, B, C dimensions

Claims (1)

(57) [Claims] 1. A corrugated tube that covers an electric wire and has a conductive plating on the surface, a coupler that has one end on which the corrugated tube is locked, and has a conductive plating applied on a surface through which the electric wire is inserted. In a wire shield structure including a corrugated retainer having a surface plated with conductive plating for connecting the corrugated tube to the coupler, a half-split member that constitutes the tubular corrugated retainer in combination, And a rib formed substantially in an elliptical shape by a combination of the split members and engaging with the corrugated tube.