JP2004214051A - Coaxial cable fixing mechanism - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coaxial cable fixing mechanism capable of stably fixing a coaxial cable to a holding fitting, and improved in reliability in electrically connecting an external conductor to a ground of a board. <P>SOLUTION: Solder is melted into a space between the inside surface of a cylindrical sleeve 1 and an external conductor exposure part 3a to fix the cylindrical sleeve 1 to the exposure part 3a; the holding fitting 11 covering the cylindrical sleeve 1 up to an area exceeding 270° is mounted; a stepped part 1a formed in the circumference of the cylindrical sleeve 1 is caught and fitted to hold and fix it to the holding fitting 11; and the coaxial cable 8 is electrically connected to the ground of the board 10. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a coaxial cable fixing mechanism, and more particularly to a coaxial cable fixing mechanism used for a foldable mobile phone.
[0002]
[Prior art]
2. Description of the Related Art In recent years, the spread of mobile phones has been remarkable. Particularly, in the case of a foldable mobile phone, an antenna is arranged on an upper part of the fold, a wireless circuit board is arranged on a lower part, and the antenna and the wireless circuit are arranged. Although a coaxial cable is used to deliver an RF (Radio Frequency) signal, an external conductor at an intermediate portion of the coaxial cable is generally connected to a substrate in order to secure radio characteristics such as impedance characteristics and shield characteristics. It is configured to be electrically connected to the ground (GND).
[0003]
A conventional coaxial cable fixing mechanism of this type will be described with reference to the drawings.
[0004]
FIG. 6 is a perspective view showing a conventional coaxial cable fixing mechanism 100, and FIG. 7 is a cross-sectional view showing the relationship between the holding fitting 111 and the caulking member 101 in FIG.
[0005]
Referring to FIGS. 6 and 7, the coaxial cable fixing mechanism 100 includes a coaxial cable 108 and a holding bracket 111 fixed to a ground (not shown) of the substrate 110. A portion where the outer conductor 103 is exposed by removing the coating, and a caulking member 101 fixed to the exposed portion of the outer conductor 103 by a caulking method are provided. The caulking member 101 is held by the elastic deformation force of the holding metal 111. It is configured so as to be held and fixed by being sandwiched inside, so that conduction between the external conductor 103 and the ground (GND) of the substrate 110 is established.
[0006]
When the caulking member 101 is attached to the outer periphery of the outer conductor 103 of the coaxial cable 108, the finished outer shape of the caulking member 101 does not have a cylindrical shape, but has an elliptical shape or a distorted shape. There is a problem that the member 101 cannot be fixed stably, and there is a case where the member 101 comes off the holding bracket 111 due to the influence of external force such as vibration and impact.
[0007]
Therefore, instead of a caulking member, a cap made of a hollow cylindrical metal tube and provided with a large diameter portion and a small diameter portion in the longitudinal direction is attached to the end of the coaxial cable, and the outer conductor of the coaxial cable and the ground of the board case are mounted. There is also a device that electrically connects (for example, see Patent Document 1).
[0008]
In the technique disclosed in Patent Document 1, the inner diameter of the large diameter portion of the cap is substantially equal to the outer diameter of the outer sheath of the coaxial cable, and the inner diameter of the small diameter portion of the cap and the outer diameter of the outer conductor of the coaxial cable are substantially equal. Although they are equal, when the cap is attached to the end of the coaxial cable, three types of cases such as gap fitting, trimming fitting, and shimming occur due to variations in dimensional accuracy of the two. In addition to poor productivity, there is a problem that the production yield is deteriorated.
[0009]
[Patent Document 1]
JP-A-2-201883
[0010]
[Problems to be solved by the invention]
As described above, a conventional coaxial cable fixing mechanism that attaches a caulking member to the outer periphery of an external conductor, sandwiches the caulking member in a holding bracket, holds and fixes the caulking member, and establishes electrical continuity between the external conductor and the ground of the substrate is a caulking member. The finished outer shape becomes an elliptical shape or a distorted shape, so that the caulking member cannot be stably fixed to the holding metal, and there is a problem that a case may occur in which the caulking member comes off the holding metal due to an external force such as vibration or impact.
[0011]
Also, a technique of attaching a cap provided with a large-diameter portion and a small-diameter portion to a hollow cylindrical metal tube at an end of a coaxial cable and electrically connecting an external conductor of the coaxial cable and a ground of a board case is known. However, there is a problem in that the dimensional accuracy between the coaxial cable and the cap is difficult to manage, the productivity in the process of attaching the cap to the end of the coaxial cable is reduced, and the manufacturing yield is deteriorated.
[0012]
An object of the present invention is to solve the above-mentioned problems, to stably fix a coaxial cable to a holding bracket without lowering a manufacturing yield, and to improve reliability when establishing continuity between an external conductor and a ground of a substrate. To provide a coaxial cable fixing mechanism.
[0013]
[Means for Solving the Problems]
The coaxial cable fixing mechanism of the present invention has a coaxial cable and a holding metal fixed to the ground of the substrate, and the coaxial cable is inserted into the exposed outer conductor and the outer conductor where the coating of the intermediate portion is removed. And a cylindrical sleeve fixed to the outer conductor exposed portion by solder, and the holding fitting holds and fixes the cylindrical sleeve.
[0014]
The inside diameter of the cylindrical sleeve and the outside diameter of the coaxial cable have a clearance fit, and the solder is melted in the gap between the inside diameter of the cylindrical sleeve and the external conductor exposed portion to fix the cylindrical sleeve and the external conductor exposed portion. It is characterized by.
[0015]
The cylindrical sleeve is characterized in that it has a step portion wider than the width of the holding bracket at the center.
[0016]
The cylindrical sleeve has a bent shape of 90 degrees or less, and the holding fitting holds and fixes the cylindrical sleeve at a plurality of positions.
[0017]
The holding fitting holds and fixes the cylindrical sleeve at two linear portions sandwiching the bent portion of the cylindrical sleeve.
[0018]
The holding fitting has an arc-shaped portion that covers the outer diameter of the cylindrical sleeve, and the side opposite to the side fixed to the substrate has an arc-shaped outer folded portion.
[0019]
The arc-shaped portion has an angle of more than 270 degrees.
[0020]
The holding fitting includes a metal material for a spring.
[0021]
The holding fitting holds and fixes the outer diameter of the cylindrical sleeve by elastic deformation force.
[0022]
The external conductor exposed portion and the ground of the substrate are electrically connected via a cylindrical sleeve and a holding metal.
[0023]
The cylindrical sleeve has a long hole in the longitudinal direction.
[0024]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, a first embodiment of the coaxial cable fixing mechanism of the present invention will be described with reference to the drawings.
[0025]
FIG. 1 is a schematic perspective view showing a first embodiment of a coaxial cable fixing mechanism 20 of the present invention, FIG. 2 is a perspective view showing details of a coaxial cable 8 in FIG. 1, and FIG. FIG. 4 is a perspective view showing details of the inner cylindrical sleeve 1, and FIG. 4 is a sectional view showing a relationship between the holding fitting 11 and the cylindrical sleeve 1 in FIG.
[0026]
Referring to FIGS. 1 and 2, the coaxial cable fixing mechanism 20 includes a coaxial cable 8 and a holding bracket 11 fixed to a ground (not shown) of the substrate 10. An insulator 6 covering the outside of the center conductor 5; an outer conductor 3 covering the outside of the insulator 6 in a mesh form; a coating 4 covering the outside of the external conductor 3; It has an exposed portion 3a, and a cylindrical sleeve 1 inserted into the outer conductor exposed portion 3a and fixed to the outer conductor 3 of the outer conductor exposed portion 3a by solder 2, and holds the cylindrical sleeve 1 by the elastic deformation force of the holding fitting 11. It is configured so as to be held and fixed by being sandwiched in the metal fittings 11 so as to establish conduction between the external conductor 3 and the ground of the substrate 1.
[0027]
A method of fixing the holding metal 11 to the ground of the substrate 10 is not shown, but is fixed by screws or fixed by soldering.
[0028]
Referring to FIG. 3, the cylindrical sleeve 1 is provided with a step portion 1a wider than the width of the holding metal fitting 11 and a long hole 1b drawn in the longitudinal direction L at the center.
[0029]
Referring to FIG. 4, the holding bracket 11 is made of a metal material for a spring (for example, a material such as SUP3 is formed into a sheet metal and then subjected to a baking process), and has an arc-shaped portion covering the outer diameter of the cylindrical sleeve 1. An arc-shaped outer folded portion 11a is provided on the side opposite to the fixing portion 11b on the side fixed to 10, and the arc-shaped portion is provided to extend beyond the radius of the cylindrical sleeve 1, that is, has an angle larger than 270 degrees It has a configuration.
[0030]
Next, an operation of attaching the coaxial cable 8 to the substrate 10 of the coaxial cable fixing mechanism 20 configured as described above will be described with reference to the drawings.
[0031]
Referring to FIGS. 1 to 4, the coating 4 of the intermediate portion of the coaxial cable 8 is removed, and the cylindrical sleeve 1 is inserted into the exposed outer conductor 3 of the exposed outer conductor 3 a. Is fixed by the solder 2, and the step portion 1 a of the cylindrical sleeve 1 is fitted into the holding metal 11 provided on the substrate 10 and fixed to the ground (GND) pattern.
[0032]
The gap between the outer conductor 3 and the inner diameter of the cylindrical sleeve 1 is fixed by the solder 2 at both ends of the cylindrical sleeve 1 and also by the solder 2 at the long hole 1b so that the gap between the two can be further improved. Can be fixed firmly.
[0033]
The inner diameter of the cylindrical sleeve 1 and the outer diameter 8a of the coaxial cable form a clearance fit, the solder is melted into the gap between the inner diameter of the cylindrical sleeve 1 and the outer conductor exposed part 3a, and the cylindrical sleeve 1 and the outer conductor exposed part 3a Is fixed, and the step portion 1a of the cylindrical sleeve 1 is fitted into the holding metal fitting 11, whereby the external conductor exposed portion 3a and the ground of the substrate 10 are electrically connected via the cylindrical sleeve 1 and the holding metal fitting 11.
[0034]
Generally, the dimensional accuracy of the finished outer shape of the step portion 1a of the cylindrical sleeve 1 can be manufactured with high accuracy, the coaxial cable 8 can be stably fixed to the holding metal member 11, and the holding metal member 11 is made of a metal material for a spring. A structure that covers a position lower than the center (center of gravity) of the sleeve 1 (a range exceeding the 270 degree of the cylindrical sleeve 1). The elastic deformation force sandwiches and holds and holds the step portion 1a of the cylindrical sleeve 1, thereby causing vibration and impact. Thus, it is completely prevented from being detached from the holding fitting 11 due to the influence of an external force such as the above.
[0035]
Next, a second embodiment of the coaxial cable fixing mechanism of the present invention will be described with reference to the drawings.
[0036]
FIG. 5 is a schematic plan view showing a second embodiment of the coaxial cable fixing mechanism 30 of the present invention (the same components as those of the coaxial cable fixing mechanism 20 of the first embodiment are denoted by the same reference numerals). To display).
[0037]
Referring to FIG. 5, the coaxial cable fixing mechanism 30 includes a coaxial cable 8 and a holding bracket 11 fixed to a ground (not shown) of the substrate 13. A covering film 4, an outer conductor exposed portion 3a from which an intermediate portion of the covering 4 has been removed, and a bent cylinder inserted into the outer conductor exposed portion 3a and fixed to the outer conductor 3 of the outer conductor exposed portion 3a by solder (not shown). A sleeve 18 is provided, and the stepped portion 18b of the bent cylindrical sleeve 18 is sandwiched and held and fixed in the holding metal fitting 11 by the elastic deformation force of each of the two holding metal fittings 11. (Not shown).
[0038]
As described above, the difference from the coaxial cable fixing mechanism 20 of the first embodiment is that the bent cylindrical sleeve 18 is disposed instead of the cylindrical sleeve 1 and the holding fitting 11 is bent at the straight portion of the bent cylindrical sleeve 18. Only the point of holding and fixing at two places will be described below.
[0039]
The bent cylindrical sleeve 18 is formed with a bent shape of 90 degrees or less (an angle at which the cylindrical sleeve is bent), and the holding metal fitting 11 is bent at two positions of a straight portion sandwiching the bent portion 18a of the bent cylindrical sleeve 18. The sleeve 18 is held and fixed.
[0040]
Accordingly, when wiring is performed at a location where the coaxial cable 8 is formed into a curved shape, bending forming can be performed accurately and easily, and adverse effects on electrical characteristics due to variations in the wiring at the location where the forming is performed can be prevented. .
[0041]
【The invention's effect】
As described above, the coaxial cable fixing mechanism of the present invention fixes the cylindrical sleeve and the outer conductor exposed portion by melting the solder between the inner diameter of the cylindrical sleeve and the outer conductor exposed portion, and fixes the outer periphery of the cylindrical sleeve. The coaxial cable is stably fixed to the holding bracket by fitting the stepped portion into the holding bracket and connecting the ground between the coaxial cable and the board in a conductive manner, and the reliability when establishing continuity between the coaxial cable and the ground of the board. There is an effect that can be improved.
[0042]
In addition, the holding fitting covers the cylindrical sleeve to a range exceeding 270 degrees, and holds and fixes the stepped portion of the cylindrical sleeve by its elastic deformation force. Therefore, the holding fitting is detached from the holding fitting by the influence of external force such as vibration and impact. This has the effect that it can be completely prevented.
[0043]
Furthermore, by forming a bent cylindrical sleeve and forming the coaxial cable in a curved shape inside the bent cylindrical sleeve, the forming of the coaxial cable can be performed accurately and easily, and the electrical characteristics resulting from the variation in the wiring at the forming location. This has the effect of preventing the above adverse effects.
[Brief description of the drawings]
FIG. 1 is a schematic configuration perspective view showing a first embodiment of a coaxial cable fixing mechanism of the present invention.
FIG. 2 is a perspective view showing details of a coaxial cable shown in FIG. 1;
FIG. 3 is a perspective view showing details of a cylindrical sleeve in FIG. 2;
FIG. 4 is a cross-sectional view showing a relationship between a holding bracket and a cylindrical sleeve in FIG.
FIG. 5 is a schematic configuration plan view showing a second embodiment of the coaxial cable fixing mechanism of the present invention.
FIG. 6 is a plan view showing a conventional coaxial cable fixing mechanism.
FIG. 7 is a cross-sectional view showing a relationship between a holding bracket and a caulking member in FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Cylindrical sleeve 1a, 18b Step part 1b Slotted hole 2 Solder 3, 103 External conductor 3a External conductor exposed part 4 Coating 5 Center conductor 6 Insulator 8, 108 Coaxial cable 8a Coaxial cable outer diameter 10, 13, 110 Substrate 11, 111 Holding metal fitting 11a Outer folded portion 11b Fixed portion 18 Bending cylindrical sleeve 18a Bending portion 101 Caulking members 20, 30, 100 Coaxial cable fixing mechanism L Longitudinal direction

Claims (11)

A coaxial cable, and a holding bracket fixed to a ground of the substrate, wherein the coaxial cable has an outer conductor exposed portion having an intermediate portion removed, and an outer conductor exposed portion inserted into the outer conductor exposed portion and soldered. A coaxial cable fixing mechanism, comprising: a cylindrical sleeve fixed to the portion; and the holding fitting holds and fixes the cylindrical sleeve. The inner diameter of the cylindrical sleeve and the outer diameter of the coaxial cable have a clearance fit, and the solder is melted in the gap between the inner diameter of the cylindrical sleeve and the outer conductor exposed portion to expose the cylindrical sleeve and the outer conductor exposed portion. 2. The coaxial cable fixing mechanism according to claim 1, wherein the first and second portions are fixed. The coaxial cable fixing mechanism according to claim 1, wherein the cylindrical sleeve has a step portion wider than a width of the holding bracket at a central portion. The coaxial cable fixing mechanism according to claim 1, wherein the cylindrical sleeve has a bent shape of 90 degrees or less, and the holding fitting holds and fixes the cylindrical sleeve at a plurality of positions. The coaxial cable fixing mechanism according to claim 4, wherein the holding fitting holds and fixes the cylindrical sleeve at two linear portions sandwiching the bent portion of the cylindrical sleeve. 2. The coaxial cable according to claim 1, wherein the holding metal has an arc-shaped portion covering an outer diameter of the cylindrical sleeve, and a side opposite to a side fixed to the substrate has an arc-shaped outside folded portion. 3. Cable fixing mechanism. The coaxial cable fixing mechanism according to claim 6, wherein the arc-shaped portion has an angle greater than 270 degrees. The coaxial cable fixing mechanism according to any one of claims 1, 4, 5, and 6, wherein the holding fitting has a metal material for a spring. The coaxial cable fixing mechanism according to any one of claims 1, 4, 5, and 6, wherein the holding fitting holds and fixes the outer diameter of the cylindrical sleeve by an elastic deformation force. 2. The coaxial cable fixing mechanism according to claim 1, wherein the outer conductor exposed portion and the ground of the substrate are electrically connected via the cylindrical sleeve and the holding metal. 3. The coaxial cable fixing mechanism according to claim 1, wherein the cylindrical sleeve has a long hole in a longitudinal direction.

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