JP2005044662A - Coaxial cable fixing structure of interphone - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an interphone coaxial cable fixing structure that can fix a plurality of coaxial cables simply to the circuit board with only one side of the substrate. <P>SOLUTION: The coaxial cable 3 is arranged so that it is crimped to the surface of the circuit board 2 with a crimp fittings 4, one terminal fittings 5 having a plurality of tap holes to fix a plurality of the crimp fittings 4 is arranged at the rear face of the circuit board 2, and these crimp fittings 4 are screwed into the terminal fittings 5 and 3 coaxial cables 3, 3, 3 are fixed to the circuit board 2. The terminal fittings 5 has a braided conductor coupling part protruding to the lower part of the crimp fittings 4 via the aperture part of the circuit board 2, and when the coaxial cable 3 is fixed, the braided conductor of the coaxial cable 3 is connected to the terminal fittings 5. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a coaxial cable fixing structure of an interphone, and more particularly to a coaxial cable fixing structure of an interphone using a fixing portion of the coaxial cable as a circuit board.

As a form of fixing a coaxial cable to an intercom device, a configuration shown in Patent Document 1 and a configuration shown in FIG. 5 are known. Patent Document 1 has a structure that is fixed to a case of an interphone device formed by resin molding or the like. A coaxial cable is sandwiched between a terminal metal fitting and a holding metal fitting, and a screw is tightened to fix.
FIG. 5 shows a form of fixing on the circuit board of the interphone device, 21 is a case of the interphone device, 22 is a coaxial cable, 23 is a pressing metal fitting, and 24 is a circuit board. The presser fitting 23 has a cable holding portion 23a in the center and is provided with screwing portions at both ends thereof. The coaxial cable 22 is held by the presser fitting 23 and pressed against the circuit board 24 to hold the coaxial cable 22 in place. It was fixed. The fixing is performed by connecting the presser fitting 23 and the circuit board 24 with the screw 25 and the nut 26 and the case 21. The central conductor 22a of the coaxial cable 22 was fixed to the circuit board 24 by a connection fitting 27 provided separately.
Japanese Utility Model Publication No. 62-77875

However, among the above configurations, the one shown in Patent Document 1 is a case where the fixing portion is a case, so that it is difficult to obtain a sufficient strength because the rigidity of the screw stopper is weak. In addition, a pair of terminal bracket and holding bracket was necessary. Further, it is necessary to separately connect the ground portion of the circuit board and the ground conductor of the coaxial cable.
In the configuration shown in FIG. 5, the coaxial cable 22 can be firmly fixed by using the screw 25 and the nut 26, but when there are a plurality of the coaxial cables 22, the holding fitting 23 is provided for each coaxial cable 22. A pair of screws 25 and a pair of nuts 26 are necessary, and the number of parts used is large, and the fixing work is troublesome. Further, the central conductor 22a of the coaxial cable 22 can be connected to the circuit pattern formed on the back surface by projecting the connection fitting 27 on the back surface of the circuit board 24, but the braided conductor (earth conductor) 22b is the front surface. The circuit pattern formed in (2) is connected by the press-contacting action of the presser fitting 23, and can only be handled by a double-sided board.

  Therefore, in view of the above-mentioned problems, the present invention can easily fix a plurality of coaxial cables in a form of fixing to a circuit board that is easy to obtain strength, and even if a single-sided board is used, electrical connection between the coaxial cable and the circuit board can be achieved. It is an object of the present invention to provide a coaxial cable fixing structure of an intercom that can be easily realized.

In order to solve the above-mentioned problems, the invention of claim 1 is directed to an interphone coaxial for connecting and fixing a plurality of coaxial cables to which signals from a plurality of external devices such as an entrance cordless handset and a surveillance camera are transmitted to an interphone master unit. A cable fixing structure having a plurality of pressure fittings for individually pressing a plurality of coaxial cables against the component surface of the circuit board of the interphone master unit, and a tap hole for fixing the plurality of pressure fittings. And a terminal fitting disposed on the solder surface of the board, and the plurality of coaxial cables are fixed to the circuit board by connecting the pressure fitting and the terminal fitting with screws with the circuit board interposed therebetween.
With this configuration, nuts are not individually required for a plurality of coaxial cables, so that fixing members can be reduced. Therefore, the number of work steps to be fixed can be reduced, and the fixing work can be simplified.

According to a second aspect of the present invention, in the first aspect of the invention, the connection fitting for connecting the central conductor of the coaxial cable is disposed on the component surface of the circuit board, and is formed on the solder surface through an opening provided in the circuit board. While the terminal is electrically connected to the circuit pattern, a portion of the terminal fitting has a protruding portion that penetrates the circuit board and is exposed on the component surface, and the braided conductor of the coaxial cable comes into contact with the protruding portion. The ground is taken by the circuit pattern of the solder surface in contact with the terminal metal fitting through the metal fitting, and the circuit board can be connected to the coaxial cable only by the circuit pattern of the solder surface.
According to the second aspect of the present invention, a single-sided board provided with a circuit pattern only on the solder surface can be connected to the coaxial cable, and the circuit board can be made inexpensive.

According to a third aspect of the present invention, in the second aspect of the present invention, the protruding portion of the terminal fitting is exposed to the component surface through an opening formed in the circuit board and is located directly below the cable holding portion of the pressure fitting. It is characterized by.
With this configuration, the braided conductor of the coaxial cable can be surely brought into contact with the terminal fitting by the press-contacting action of the pressing fitting, and a good connection state can be obtained.

According to a fourth aspect of the present invention, in the invention of any one of the first to third aspects, when three or more coaxial cables to be fixed are parallel to each other, the plurality of press-fit fittings are staggered so as to be staggered in the cable direction. It is characterized by becoming.
With this configuration, a plurality of press fittings can be arranged in a space-saving manner, and even if there are a plurality of coaxial cables to be fixed, only a small space is required.

The invention of claim 5 is the invention according to any one of claims 1 to 4, wherein the terminal fitting is fixed to the interphone base unit case together with the circuit board with at least one screw, and is formed in the case fixing portion of the circuit board. The screw insertion hole is provided with a circuit pattern without a protective resist around it, and by fixing the terminal fitting to the case, the terminal fitting and the circuit pattern without the protective resist are in contact with each other, and both are in a conductive state.
With this configuration, the terminal board and the circuit board can be securely connected to each other by fixing the circuit board to the case.

The invention of claim 6 is characterized in that, in the invention of claim 5, only one of the screw insertion holes of the case fixing portion of the circuit board is provided with a circuit pattern having no protective resist around it.
With this configuration, since the terminal fitting and the circuit board are electrically connected to each other only at one place, high-frequency signals such as video signals can be transmitted satisfactorily.

  As described above, according to the present invention, the use of the terminal fitting does not require a nut for each of the plurality of coaxial cables, the number of fixing members can be reduced, and the fixing operation can be simplified. Further, since the ground portion of the coaxial cable can be grounded on the solder surface of the circuit board by the projecting portion exposed on the component surface, it can be handled by a single-sided board, and an inexpensive circuit board can be used.

  DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, embodiments of the invention will be described in detail with reference to the drawings. FIG. 1 shows a coaxial cable fixing structure of an interphone according to the present invention, and shows a perspective view inside the interphone base unit. In the figure, 1 is a base unit case, 2 is a circuit board, 3 is a coaxial cable, 4 is a press-contact metal fitting for press-contacting the coaxial cable 3 to the circuit board 2, and 5 is arranged on the back surface, which is the solder surface of the circuit board 2. A terminal metal fitting 6 for fixing the metal fitting 4 is a connection metal fitting 6 for connecting the central conductor 3a of the coaxial cable 3 to the circuit board 2. Here, a configuration for fixing the three coaxial cables 3, 3, 3 is shown. ing.

  The press fitting 4 has a cable holding portion 4a formed in an arch shape in the center, and is formed by providing a fixing piece 4b provided with screw insertion holes at both left and right ends thereof. The circuit board 2 is formed by two screws 7 and 7. It is fixed to the surface which is the component surface. Further, as shown in the exploded view of FIG. 4, the connection fitting 6 is formed by bending a U-shape and is provided with a metal seat plate 6a having a screw hole in the center and a central conductor 3a pressed against the seat plate 6a. And a pressure contact plate 6b for connecting the two, the two are connected by a screw 8, and the central conductor 3a is connected. And the seat board 6a has the tongue piece 6c extended below, the tongue piece 6c is inserted in the hole provided in the circuit board 2, and is soldered to the circuit pattern formed on the back surface. Simultaneously with the electrical connection, the seat plate 6a is fixed.

FIG. 2 is an explanatory diagram in which the terminal fitting 5 and the coaxial cable 3 are extracted. As shown in the figure, the terminal fitting 5 has three press-fit fitting connecting portions 9 that are staggered forward and backward with respect to the coaxial cable entry direction. The three coaxial cables are arranged in parallel. Specifically, the press-connecting bracket connecting portion 9 is composed of a braided conductor connecting portion 9a as a projecting portion formed by bending upward, and a tap hole 9b for connecting the press-connecting bracket 4 provided on both sides of the braided conductor connecting portion 9a. The conductor connecting portion 9a is formed as a pair of parallel sides formed by bending in a U-shape, and its tip is flush with the surface of the circuit board 2 when the terminal fitting 5 is assembled to the back surface of the circuit board 2. It is formed with the height which becomes.
Thus, by providing the braided conductor connecting portion 9a in the middle of the pair of tap holes 9b, 9b, the braided conductor connecting portion 9a is arranged directly below the cable holding portion 4a of the press fitting 4, and the coaxial cable 3 is fixed by pressure. In this case, the braided conductor 3b lifted up can be securely connected to the terminal fitting, and when there are a plurality of pressure fittings, the coaxial cable can be fixed in a space-saving manner by arranging them in a staggered manner. Reference numeral 10 denotes a screw insertion hole for fixing the base case 1 with screws.

FIG. 3 is a rear view of the circuit board 2, and the terminal fitting 5 assembled on the rear surface is indicated by a two-dot chain line. As shown in FIG. 3, the circuit board 2 is formed with a pair of rectangular openings 11 through which the braided conductor connecting portion 9a of the terminal fitting 5 is inserted and exposed to the surface. A screw insertion hole 12 for screwing the screw 7 into the tap hole 9b of the metal fitting 5 is provided. Reference numeral 13 denotes a hole through which the tongue 6c of the seat plate 6a is inserted. The signal circuit pattern P1 connected to the central conductor 3a of the coaxial cable 3 and the braided conductor 3b are connected to the back surface of the circuit board 2. Both the ground part circuit pattern P2 and the seat plate 6a are connected to the signal part circuit pattern P1 by soldering the tongue piece 6c.
Further, around the screw insertion hole 15 of the circuit board 2 that coincides with the screw insertion hole 10 of the terminal fitting 5, a circuit pattern 14 is formed in which a part of the earth circuit pattern P2 is exposed without providing a protective resist. ing. When the circuit board 2 is fixed to the base case 1 with screws, the terminal fitting 5 is connected to the exposed circuit pattern 14 and is connected to the earth circuit pattern P2. All circuit patterns that can be in contact with the terminal fitting 5 other than the exposed circuit pattern 14 are covered with the protective resist so that they do not come into contact with each other.

  In this way, the terminal fitting 5 and the circuit board are electrically connected at one place and become in a conductive state, whereby a good connection can be made without causing an electrical wrap around the high frequency signal, and the coaxial cable 3. And the connection with the circuit pattern of the circuit board 2 can be made favorable.

Next, the coaxial cable fixing procedure of the coaxial cable fixing structure will be described. First, the end of the coaxial cable 3 to be connected is processed as shown in FIG. By this processing, an appropriate amount of the central conductor 3a is exposed, and the braided conductor 3b, which is an external conductor, is rolled up on the protective coating. Next, as shown in FIG. 1, the center conductor 3 a is inserted between the seat plate 6 a and the pressure contact plate 6 b that are soldered and fixed to the circuit board 2 of the connection fitting 6 in advance. At this time, the coaxial cable 3 is positioned so that the braided conductor 3b of the coaxial cable 3 is placed on the braided conductor connecting portion 9a of the press-fit fitting connecting portion 9 (on the opening 11 through which the braided conductor connecting portion 9a is inserted). Keep it. Then, the central conductor 3a is fixed with the screw 8. By this operation, the center conductor 3a is connected to the circuit pattern P1 formed on the back surface of the circuit board 2 through the seat plate 6a.
Then, the pressure fitting 4 is placed on the coaxial cable 3, the terminal fitting 5 is disposed at a predetermined position on the back surface of the circuit board 2, and the pressure fitting 4 is fixed to the terminal fitting 5 with screws 7. At this time, since the braided conductor 3b of the coaxial cable 3 is on the braided conductor connecting portion 9a exposed flush with the surface of the circuit board 2, the braided conductor 3b is excellently connected to the terminal metal fitting 5 by pressure contact with the pressure welding metal fitting 4. Connected. In addition, the fixing procedure of the connection fitting and the pressure fitting may be reversed.
Thereafter, the circuit board 2 and the terminal fitting 5 are fixed to the base unit case 1. That is, the braided conductor 3b is connected to the circuit pattern P2 via the terminal fitting 5 by inserting screws into the screw insertion holes 15 of the circuit board 2 and the screw insertion holes 10 of the terminal fitting 5 and fixing them with screws. .

Thus, since it can respond and fix with respect to several coaxial cable with one terminal metal fitting, a fixing member can be reduced without requiring a nut individually. As a result, the number of work steps to be fixed can be reduced, and the fixing work can be simplified.
In addition, the terminal fitting has a braided conductor connecting part that contacts the braided conductor, and the coaxial cable arranged on the front surface of the circuit board can be easily connected to the circuit pattern provided on the back surface. Can reduce costs.
Furthermore, since the coaxial cable is pressed and fixed on the circuit board by the press-contact fitting, the braided conductor can surely contact the terminal fitting, and a good connection state can be obtained.

In the above embodiment, one place of the terminal metal fitting 5 is fixed to the base unit case 1 together with the circuit board 2, and the circuit board 2 and the terminal metal fitting 5 are electrically connected at the fixing portion to improve the high frequency characteristics. However, when the terminal fitting 5 is fixed to the base unit case at a plurality of locations, the terminal fitting 5 and the circuit board may be electrically connected at the plurality of locations, and the high frequency characteristics may deteriorate. The electrical connection with can be ensured.
The braided conductor connecting portion 9a is formed so as to be flush with the surface of the circuit board 2. However, the braided conductor connecting portion 9a may be formed so as to slightly protrude from the surface. You may form so that a cable may be hold | maintained easily. Moreover, although formed by two parallel sides forming a pair, it may be formed by only one side.

It is an internal perspective view of the intercom master which shows the coaxial cable fixing structure of the intercom which concerns on this invention. It is the perspective view which extracted the terminal metal fitting and coaxial cable of FIG. It is the figure which looked at the circuit board of FIG. 1 from the back surface. It is a disassembled perspective view of a connection metal fitting. The coaxial cable fixing structure of the conventional intercom is shown, (a) is plane explanatory drawing, (b) is AA sectional view.

Explanation of symbols

  1 .... Base unit case 2 .... Circuit board 3 .... Coaxial cable 4 .... Pressure fitting 5 ... Terminal fitting 6 ... Connection fitting 7 ... Screw 9 ... Pressure fitting connecting part 9a ... Braided conductor connecting part (projection part), 9b ... Tap hole, 10 ... Screw insertion hole, 11 ... Opening part, 13 ... Hole (opening part), 14 ... Exposed circuit pattern, 15 ..Screw insertion hole, P1..Signal part circuit pattern, P2..Earth part circuit pattern.

Claims (6)

An interphone coaxial cable fixing structure for connecting and fixing a plurality of coaxial cables to which the signals from a plurality of external devices such as an entrance unit and a surveillance camera are transmitted to the interphone main unit,
A plurality of press fittings for individually press-contacting the plurality of coaxial cables to a component surface of the circuit board of the interphone master unit; and a tap hole for fixing the plurality of press-contact fittings, and soldering the circuit board With one terminal fitting placed on the surface,
A coaxial cable fixing structure for an interphone, wherein the plurality of coaxial cables are fixed to the circuit board by connecting the pressure-contact metal fitting and the terminal metal fitting with a screw across the circuit board. The connection fitting for connecting the central conductor of the coaxial cable is disposed on the component surface of the circuit board and is electrically connected to a circuit pattern formed on the solder surface through an opening provided in the circuit board.
A part of the terminal fitting includes a protruding portion that penetrates the circuit board and is exposed on a component surface thereof, and a braided conductor of the coaxial cable contacts the protruding portion, and the terminal fitting is interposed via the terminal fitting. Is grounded by the circuit pattern of the solder surface in contact with
2. The interphone coaxial cable fixing structure according to claim 1, wherein the circuit board can be connected to the coaxial cable only by a circuit pattern on a solder surface. 3. The interphone coaxial according to claim 2, wherein the protruding portion of the terminal fitting is exposed to the component surface through an opening formed in the circuit board and is located directly below the cable holding portion of the pressure fitting. Cable fixing structure. 4. When the number of coaxial cables to be fixed is three or more parallel to each other, the plurality of press-fitting metal fittings are staggered so as to be staggered back and forth in the cable direction. Intercom coaxial cable fixing structure. The terminal fitting is fixed to the intercom base unit case together with the circuit board with at least one screw, and the screw insertion hole formed in the case fixing portion of the circuit board includes a circuit pattern without a protective resist around the terminal fitting.
5. The interphone according to claim 1, wherein the terminal metal fitting is fixed to the case so that the terminal metal fitting and the circuit pattern without the protective resist come into contact with each other, and both are in a conductive state. Coaxial cable fixing structure. 6. The interphone coaxial cable fixing structure according to claim 5, wherein only one of the screw insertion holes of the case fixing portion of the circuit board is provided with a circuit pattern having no protective resist around it.

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