JPH0577865U - Coaxial cable terminal - Google Patents

Abstract

(57) [Abstract] [Purpose] For example, when circuit boards are connected to each other by a coaxial cable, the conventional method causes the central conductor of the coaxial cable to be exposed, which causes deterioration of the standing wave ratio. The idea is to prevent it. [Structure] An inner conductor (8), a cylindrical insulator (9) provided so as to expose a contact portion (83) of the inner conductor (8) with the outer periphery of a fixed portion (82) of the inner conductor, and a cylindrical insulator (9) enclosing these. Of the outer conductor (5) provided so as to cover, the conductive annular body (6) provided so as to communicate with the side portion of the inner conductor enclosing portion of the outer conductor (5), and the outer conductor (5) This is prevented by forming a coaxial cable terminal having a ground terminal leg provided at the end of the side portion and connecting the exposed center conductor of the coaxial cable (2) to the inner conductor (8) thereof.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a coaxial cable terminal when a coaxial cable is directly fixedly connected to a circuit board by soldering or the like.

[0002]

[Prior Art]

 With the development of electronic technology, various circuit boards are used in electronic devices, and coaxial cables have come to be often used for electrical connection between circuit boards and between circuit boards and other electronic devices. In such a case, the connection between the circuit board and the coaxial cable may be made by connecting with a connector or directly connecting the end of the coaxial cable to a circuit terminal or the like of the circuit board by soldering or electric welding. 3A and 3B show a conventional specific example in which the coaxial cable is directly fixedly connected to the circuit board by soldering. In FIG. 3A, (1) is a circuit board. (2) is a coaxial cable, (21) is a central conductor of the coaxial cable (2), and (22) is an insulator provided on the outer peripheral portion of the central conductor (21). (23) is an outer conductor provided on the outer peripheral side of the insulator, which is generally a braid of thin metal wires. Reference numeral (24) is a sheath provided on the outer side of the outer conductor (23). In the concrete example shown by A in FIG. 3, the center conductor (21) of the coaxial cable (2) is directly soldered (13) to the circuit terminal (11) of the circuit board (1) to form the center of the coaxial cable (2). The conductor (21) is electrically connected to the circuit of the circuit board (1). The outer conductor (23) of the coaxial cable (2) is soldered (13) to the ground terminal (12) of the circuit board (1) and electrically connected to the ground circuit of the circuit board (1). The example shown in FIG. 3B is basically the same as the example shown in FIG. 3A, except that the outer conductor (23) of the coaxial cable (2) and the ground circuit of the circuit board (1) are different. This means that the electrical connection of (3) was made with the clasps (3) and the screws (4).

[0003]

[Problems to be solved by the device]

 In the conventional connection method shown in FIGS. 3A and 3B, since the central conductor (21) of the coaxial cable (1) is exposed, the change in the voltage standing wave ratio (VSWR) due to the impedance mismatch and the electromagnetic wave. Induction (EMI) occurred, which was a cause of deterioration of characteristics. The present invention has been made in view of the above circumstances, and an object thereof is to provide a coaxial cable terminal having improved VSWR and EMI characteristics.

[0004]

[Means of the Invention for Solving the Problems]

 The above object can be achieved by taking the following means. The means is a connecting part at the tip of the coaxial cable, an internal conductor consisting of three parts, a fixing part and a connecting part, a cylindrical insulator provided on the outer periphery of the fixing part of this conductor, and this insulator. An annular body made of an electrically conductive material, which is made up of a tubular outer conductor as a whole, which covers the inner conductor connection part and the inner conductor covering part of the outer conductor. And a cable terminal provided with a ground terminal leg is attached to the side portion of the end portion of the fixed portion of the inner conductor of the outer conductor.

[0005]

[Action]

 When the cable terminal of the present invention is used, the inner conductor and the center conductor of the coaxial cable are covered up to the circuit board surface, so that the VSWR value as designed can be obtained and protection from electromagnetic interference is also provided.

[0006]

【Example】

 A coaxial cable terminal according to the present invention will be described with reference to the drawings. FIG. 1 shows a specific example of the coaxial cable terminal according to the present invention. In FIG. 1, (1) is a circuit board. (2) is a coaxial cable. (5) is an outer conductor of the coaxial cable terminal, and has a cylindrical shape as a whole, and is provided with a lid (51) on the top thereof. This outer conductor (5) is usually made of metal, and can be manufactured by using a metal plate as a material, such as punching, bending, and other sheet metal working. Of course, it may be manufactured by machining such as cutting from a metal material. (6) is a ring. This annular body (6) may be manufactured integrally with the outer conductor (5) or may be separately prepared and attached to the outer conductor (5) by welding, soldering, bending or the like. (7) is a ground terminal leg. Similar to the ring-shaped body (6), the ground terminal leg (7) may be integrally formed with the outer conductor (5) or may be separately prepared and attached to the outer conductor (5) later. Good. The internal structure of the coaxial cable terminal shown in FIG. 1 is as shown in FIG. In FIG. 2, (8) is the internal conductor of the terminal. Roughly speaking, the inner conductor is formed of a wire connecting portion (81), a fixing portion (82), and a connecting portion (83). (9) is an insulator. This insulator (9) is widely used in plastics having a low dielectric constant such as polyethylene and polytetrafluoroethylene, and foams thereof.

When the terminal according to the present invention is attached to the coaxial cable, first, the sheath (24) at the tip of the coaxial cable (2) is stripped off to expose the outer conductor (23) of the coaxial cable (2). Then, a part of the outer conductor (23) and the insulator (22) at the tip of the coaxial cable (2) is removed to expose the central conductor (21) of the coaxial cable (2), and the tip of the cable is removed. Finish the process. Then, the coaxial cable (2) with the tip treated is inserted into the annular body (6) of the coaxial cable terminal according to the present invention with the lid (51) at the top opened, and the center conductor (21) of the coaxial cable (2) is inserted. ) Is connected to the connection part (81) of the internal conductor (8) of the terminal. This connection may be performed by a known connection technique, and generally, soldering, welding, crimping method, etc. are adopted. Next, the coaxial cable (2) and the terminal according to the present invention are integrally fixed to each other by crimping or the like so that the annular body (6) cannot be mechanically disengaged. Then close the lid (51). By this fixing, the outer conductor (5) of the terminal according to the present invention and the outer conductor (23) of the coaxial cable (2) are electrically connected via the annular body (6). In this way, the terminal treatment of the coaxial cable for attaching the terminal according to the present invention is completed. When attaching the coaxial cable (2) to which the terminal according to the present invention is attached to the circuit board (1), insert the terminal according to the present invention into the through hole of the circuit terminal provided on the circuit board (1). Insert the contact part (83) of the internal conductor (8), and weld the ground terminal leg (7) to the ground terminal of the circuit board (1) by soldering, welding, etc. to make electrical and mechanical connection. .. The internal conductor (8) of the terminal inserted in the through hole of the circuit board can be electrically connected by soldering or the like.

[0008]

[Effect of the device]

 In the terminal of the coaxial cable according to the present invention, the inner conductor and the center conductor of the coaxial cable are covered up to the circuit board board surface, and the center conductor of the coaxial cable is not exposed. This is a remarkable effect that excellent VSWR and EMI characteristics can be obtained.

[Brief description of drawings]

FIG. 1 shows a specific example of a coaxial cable terminal according to the present invention.

FIG. 2 shows an internal structure of a coaxial cable terminal according to the present invention.

FIG. 3 is an explanatory diagram of a conventional method of connecting a coaxial cable to a circuit board.

[Explanation of symbols]

 (1) Circuit board (2) Coaxial cable (3) Fastener (4) Screwing (5) Coaxial cable terminal outer conductor (6) Annular body (7) Ground terminal leg (8) Inner conductor (9) Insulator (13) Soldering (21) Central conductor (22) Insulator (23) Outer conductor (24) Sheath (51) Lid (81) Connection part (82) Fixed part (83) Contact part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Hironobu Ishizaka 1150 Gogomiya, Shimodate City, Ibaraki Prefecture Gotomiya Plant, Hitachi Chemical Co., Ltd.

Claims (1)

[Scope of utility model registration request] 1. An internal conductor consisting of a wire connecting portion, a fixed portion and a connecting portion, a cylindrical insulator provided on the outer periphery of the fixed portion of the internal conductor, and a wire connecting portion between the insulator and the internal conductor. And an annular body made of a conductive material is provided on a side portion of the inner conductor enclosing portion of the outer conductor, which is a tubular outer conductor as a whole. Coaxial cable terminal with ground terminal legs on the side of the inner conductor end of the outer conductor.