JP2014093132A - Cable clamp structure also serving as earth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve such a problem that addition of earth to a production car due to a reason of improving performance, or the like, results in change of body parts and since the scale of change increases, quick response is impossible, and production cost increases due to increase in the number of parts.SOLUTION: In a cable clamp structure also serving as earth, a clamp metal fitting having a claw projecting toward the inside of an opening is used at one bend of an S-shaped conductive spring member having two bends. The clamp metal fitting is clamped by inserting one bend, where the claw of clamp metal fitting is formed, into the body panel end. A shield cable is held by inserting a shield exposed part, where the coating of the shield cable is removed partially, into the other bend of the clamp metal fitting and being clamped thereby.

Description

  The present invention relates to a clamp structure for fixing a shielded cable of a radio antenna for a vehicle such as an automobile to a vehicle body (hereinafter also referred to as a vehicle body or simply a body), and attachment of a ground to the vehicle body. In particular, the present invention relates to an earth / cable clamp structure having both an earth structure and a cable clamp structure.

  A coaxial cable for an automobile radio is attached to a vehicle body structure such as a body panel. The coaxial cable has a concentric structure in which an inner conductor is covered with an insulator, an outer conductor is covered around the inner conductor, and a protective coating is covered on the outermost surface. The outer conductor is formed by knitting a thin copper wire called a braided wire. A coaxial cable refers to a single-core shielded cable with a specified characteristic impedance. In the present invention, the present invention can be used for all cables in which the inner conductor is covered with an insulator and the periphery is covered with the outer conductor. Therefore, in the present invention, a shielded cable including a coaxial cable is used.

  In some cases, the shield cable is provided with a midpoint ground in the vehicle body in order to make the electric potential of the outer conductor the same as that of the vehicle body. A conventional technique for installing this ground will be described with reference to FIG. First, a part of the shield cable 121 is removed to expose the outer conductor 122. One end portion of the lead wire 131 from which the insulating coating has been removed is connected to the exposed external conductor 122 by soldering 124, and the periphery thereof is insulated and protected by the insulating tape 123.

  Next, a conductive earth terminal 133 is provided at the other tip of the lead wire 131. Then, after inserting the ground bolt 132 into the ground terminal 133, the ground bolt 132 is inserted into the conductive weld nut 134 embedded in the body panel 101 and tightened. Accordingly, the shield cable 121 and the body panel 101 are electrically coupled via the lead wire 131, and the shield cable 121 is grounded. As described above, the conventional ground installation method has a large number of parts and is expensive.

  Further, separately from the ground, the shielded cable 121 itself needs to be fixed on the body panel 101. Therefore, first, the clamp fitting 117 is attached to the shield cable 121 by various means such as tape winding. The attached clamp fitting 117 is inserted into the clamp fitting insertion port 103 opened on the body panel 101. As a result, the shielded cable 121 is attached on the body panel 101. As described above, conventionally, in addition to the ground, it is necessary to provide the clamp fitting 117 for fixing the shielded cable 121 to the body panel 101 as a separate member. For this reason, there has been a problem that the number of parts is increased and the cost is increased.

  With respect to this problem, Patent Document 1 discloses an invention in which a clamp fitting is attached to a base with a screw after the clamp fitting is attached to a shield exposed fixing portion formed by cutting a sheath of a shield cable. When this method is applied to a vehicle, the shield cable can be fixed to the vehicle body and grounded with only a clamp fitting and two screws. Therefore, the problem that the number of parts is large and the cost is high can be solved.

Japanese Utility Model Publication No. 1-140768

  In Patent Document 1, the number of parts is only a clamp metal fitting and two screws, and no lead wire is required, so the number of parts is reduced and the problem of high cost is solved. However, the processing man-hour of a screw and a screw hole is required, and the problem of high production cost by the processing man-hour remains. In addition, when it is necessary to add a ground to the production vehicle from the viewpoint of performance improvement or the like, the method of Patent Document 1 is accompanied by a change in the body parts because the clamp fitting is screwed and the mounting portion is limited. Therefore, the scale of change becomes large, and there arises a problem that quick response cannot be made.

  The present invention is a ground and cable clamp structure conceived in view of the above problems, and in a vehicle shield cable mounting structure, a body panel end portion and a shield cable are connected via a clamp fitting having two curved portions. It is characterized by securing and fixing conductivity.

More specifically, the ground and cable clamp structure of the present invention is:
The end of the body panel;
A metal plate is bent into an S shape to form two curved portions, and one of the curved portion inlets has a clamp fitting formed with a claw protruding toward the inside of the opening;
Consists of shielded cable,
The clamp fitting clamps the end of the body panel by inserting one of the curved portions where the claws of the clamp fitting are formed,
The shielded cable is held by inserting a shield exposed part obtained by removing a part of the shielded cable cover into the other curved part of the clamp fitting.

  In the cable clamp structure for both earth and ground according to the present invention, except for the shielded cable and the end of the body panel, the component configuration is a single sheet metal part that integrates the cable clamp and the earth terminal. For this reason, the number of parts is only one, and the screw for fixing to the vehicle body and the screw hole machining are not required. Therefore, the number of parts and the number of parts processing man-hours can be further reduced, and the problem of high cost due to the number of parts can be further reduced.

  In addition, the clamp fitting that sandwiches the shield cable is inserted into the end portion of the body panel such as the mating surface of the body panel. At this time, the claws provided on the clamp fitting are inserted while scraping off the vehicle body coating film. The clamp metal fitting after insertion is in direct contact with the iron panel of the body panel, ensuring electrical continuity with the body panel and fixing the shield cable to the vehicle body.

  Therefore, it is not necessary to fix the clamp fitting with screws, so that the limitation of the attachment portion is eliminated. For this reason, even if it is necessary to add ground to the production vehicle for reasons such as performance improvement, the scale of the change is small without any change in body parts. Also, depending on the case, it is possible to obtain an effect that even a quick response can be made without changing.

It is a top view which shows the component of the cable clamp structure for earth | ground which concerns on this invention. It is an assembly completion figure of the cable clamp structure for earth combined according to the present invention. It is AA sectional drawing of FIG. It is a figure which shows the example of a shape of the nail | claw of the earth combined use clamp of FIG. It is a figure showing the conventional earth structure and cable clamp structure.

  The ground / cable clamp structure of the present invention will be described below with reference to the drawings. The following description exemplifies an embodiment of the present invention, and changes within the scope of the present invention are included in the technical scope of the present invention without departing from the spirit of the present invention. Needless to say.

  FIG. 1 is an assembly view of the ground / cable clamp structure of the present invention. The shielded cable 21 is assembled to the body panel 1 via the earth / clamp fitting 11. FIG. 2 is a diagram showing a ground / cable clamp structure after the assembly of the components shown in FIG. 1 is completed.

  The surface of the body panel 1 is covered with a non-conductive coating film. The body panel 1 is formed by combining a plurality of panels. For this reason, the body panel 1 has the mating part 3 and has the body panel end part 2 which is a flange-like protrusion. In the ground / cable clamp structure according to the present invention, the body panel end 2 may include not only the mating portion 3 of the body panel 1 but also a member end that can hold the ground / clamp fitting 11.

  In order to prevent noise from being mixed into the signal in the shielded cable 21, it is necessary to provide the vehicle body with a midpoint ground where the potential of the outer conductor of the shielded cable 21 is the same as that of the vehicle body. The outermost surface of the shield cable 21 is covered with an insulating protective coating. For this reason, in order to provide the ground, it is necessary to remove the protective coating and expose the outer conductor.

  The ground / clamp metal fitting 11 is formed of an S-shaped spring member that is formed into a S-shaped cross section by performing a mountain fold and a valley fold on a conductive sheet metal. More preferably, the whole may be plated with a material having a low electrical resistance such as tin. The ground / clamp metal fitting 11 has two curved portions, a first curved portion 13 and a second curved portion 14. Further, the end of the first curved portion 13 has a claw 12 protruding toward the inside of the opening 15.

  The end portion of the first bending portion 13 may be referred to as the inlet of the first bending portion 13. Although FIG. 1 shows a state in which two claws are formed, the number of claws is not limited to two. In the present embodiment, description will be made assuming that there are two claws. Details regarding the grounding clamp metal fitting 11 will be described later.

  The AA cross section of FIG. 2 is shown in FIG. Here, referring to FIG. 1, FIG. 2, and FIG. 3 at the same time, the earth-cable cable clamp structure of the present invention will be described. In the ground / cable clamp structure of the present invention, the ground / clamp fitting 11 is fixed to the body panel 1 by the first curved portion 13, and the shield cable 21 is sandwiched between the second curved portion 14 of the ground / clamp fitting 11. It is configured by being held.

  The shielded cable 21 is partially stripped of the shielded cable 21 to provide conductivity for providing a ground, and the external conductor 22 is exposed (see FIG. 1). The external conductor 22 is inserted into the second curved portion 14 of the ground / clamp fitting 11 and is held by the ground / clamp fitting 11. At this time, the outer conductor 22 is in contact with the grounding clamp fitting 11 having conductivity, and is in an electrically conductive state.

  The body panel end 2 and the earth clamp metal fitting 11 are fixed by inserting the first curved portion 13 of the earth clamp metal fitting 11 into the body panel end 2 and pinching the body panel end 2. In some cases, after insertion, the ground / clamp fitting 11 may be pressurized from above and below to increase the gripping force. This pressurization is performed with both the shield cable 21 and the body panel end 2 inserted into the respective curved portions 13 and 14 of the ground / clamp metal fitting 11 with the upper and lower surfaces of the ground / clamp metal fitting 11 held between the pliers and the like. This can be done by pressing.

  As a result, the two claws 12 projecting toward the inside of the opening 15 at the entrance of the first curved portion 13 are press-fitted while scraping the body coating film as shown in FIG. After the press-fitting, the clamp member 11 for grounding has the claws 12 directly contact with the iron panel of the body panel 1 to secure the ground and fix the shield cable 21 to the vehicle body. At the same time, since the shield cable 21 held by the second curved portion 14 of the clamp fitting 11 for grounding is held in contact with the second curved portion 14, electrical connection for grounding is reliably ensured. Is done.

  Next, the earth / clamp fitting 11 will be described in detail. A claw 12 projects from the distal end (entrance) of the first curved portion 13 of the ground / clamp fitting 11 toward the inside of the opening 15. Although there are two nails 12 in this embodiment, two or more nails may be used.

  What is necessary is just to select suitably so that earthing | grounding can be ensured reliably and can be clamped to a vehicle body reliably. With one claw 12, the ground and clamp metal fitting 11 rotates around the claw 12, and therefore two or more claw 12 is preferable for the purpose of secure fixing. On the other hand, when it is better for the shielded cable 21 to move somewhat, the number of the claws 12 may be one.

  The claw 12 is preferably installed at the end of the first bending portion 13 and at the end located at the end of the ground / clamp fitting 11. If a claw is installed also in the facing part 16 of the claw 12 shown in FIG. 1, resistance more than necessary will be generated at the time of insertion, and it will become difficult to insert. The facing portion 16 has an effect that it is easier to operate at the initial stage of insertion if it has a smooth surface (see FIG. 4). Further, the processing of the nail to the facing portion 16 leads to an increase in the number of processing steps for the grounding / clamp fitting 11. For this reason, it is preferable to install the nail | claw 12 only in the terminal part located in the terminal of the clamp clamp 11 for earth | ground combined use.

  Further, FIG. 4 shows a side view of the grounding clamp metal fitting 11. Reference is now made to FIGS. FIG. 4A shows the shape of the claw 12 projecting directly upward toward the inside of the opening 15. FIG. 4 (b) shows the shape of the claw 12 that protrudes toward the inner side of the opening 15 in an inclined manner toward the back of the first curved portion 13 opposite to the opening 15.

  If the claw 12 protrudes toward the back of the first curved portion 13 as shown in FIG. 4 (b), the grounding clamp metal fitting 11 will come out after the grounding clamp metal fitting 11 is inserted. Even if the force is applied, the claw 12 is caught so as to oppose the direction in which it is about to come off. Therefore, it is preferable because the clamping to the body panel 1 becomes stronger and the grounding / clamp fitting 11 is difficult to come off.

  As described above, the ground / clamp metal fitting 11 according to the present invention has the nail 12 as the body panel if there is a plate-like end portion such as the mating portion 3 of the body panel 1 that can be clamped by the first curved portion 13. Since the non-conductive coating film 1 can be peeled off and grounding can be performed reliably, the workability is improved and the degree of freedom in setting the grounding clamp metal fitting 11 is increased.

  Further, since the body panel 1 is pinched, there is no need to set screws or screw holes, the manufacturing cost can be suppressed, and the flexibility of the setting location of the grounding clamp metal fitting 11 can be expanded from the viewpoint of fixing. . That is, a dual-purpose metal fitting that serves as both the ground and the clamp metal fitting (fixed) can be obtained.

  INDUSTRIAL APPLICABILITY The present invention can be suitably used not only for grounding and fixing a shield cable for a radio antenna installed in a vehicle such as an automobile, but also when other shielded cables that require grounding are routed inside the vehicle body. .

DESCRIPTION OF SYMBOLS 1 Body panel 2 Body panel edge part 3 Matching part 11 Grounding clamp metal fitting 12 Claw 13 First curved part 14 Second curved part 15 Opening 16 Claw opposing part 117 Clamp metal 21, 121 Shield cable 22, 122 External conductor 123 Insulating tape 124 Soldering 131 Lead wire 132 Earth bolt 133 Earth terminal 134 Weld nut

Claims (1)

The end of the body panel;
A metal plate is bent into an S shape to form two curved portions, and one of the curved portion inlets has a clamp fitting formed with a claw protruding toward the inside of the opening;
Consists of shielded cable,
The clamp fitting clamps the end of the body panel by inserting one of the curved portions where the claws of the clamp fitting are formed,
The shielded cable clamp structure according to claim 1, wherein the shielded cable is held by inserting a shield exposed portion from which a part of the shielded cable is removed into the other curved portion of the clamp fitting.