JPS6353673B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to the cable configuration and terminal processing of a coaxial cable that connects electronic devices with connectors.

[Conventional technology]

2. Description of the Related Art Conventionally, a coaxial cable as shown in a sectional view of FIG. 1 has been used as a coaxial cable of a connector mechanism for connecting electronic devices, and a perspective view of FIG. 2 shows a connector mounting structure thereof.

In FIG. 1, a coaxial cable 1 consists of a plurality of coaxial wires 11 bundled together and coated with an insulator, the outer circumferential surface of the insulator is covered with an entire cable shield 2, and the outer circumferential surface of the entire cable shield 2 is covered with a synthetic resin. It is covered with an outer skin.

The center conductor 3 of each coaxial strand 11 is covered with a shield layer 4 via an insulator.

In addition, 20 wires having 20 such coaxial wires 11
Core coaxial cables are widely used.

In the perspective view of FIG. 2, a connector 6 is accommodated in the opening on the front end side of a connector case 5 made of steel and forming a housing structure, and is fixed by screws.

The connector case 5 is symmetrical and partitioned left and right by a partition member provided at the center, and a lid made of a metal plate is screwed to the opening surface of the upper connector case 5.

The connector 6 is a rectangular parallelepiped molded body in which a large number of connector terminals 6a are embedded and molded, and the connector terminals 6a are a pair of connection terminals that connect each center conductor 3 and shield layer 4 of the coaxial cable 1. It consists of

Before connecting the coaxial wires 11 to the connector, the coaxial wires 11 are bundled by wrapping tape or the like and connected directly to the connector terminal 6a, or each coaxial wire 11 is divided into two sets and each set is connected using a cable clamp 8. It is fixed to the bottom of the connector case 5 with screws.

Center conductor 3 and shield layer 4 of coaxial wire 11
is attached to the connector terminal 6a by soldering, etc., and is connected to the connector on the device side.
Serves as a cable connector for connecting devices.

After inserting such a connector 6 into the device side connector attached to the device frame, the device fixing screw 7 is inserted into the hole provided in the partition member of the connector case 5, and the connector case 5, that is, the connector 6 is inserted. It is designed to be fixed to the equipment frame.

On the other hand, a shield lead wire is provided at the end of the entire cable shield 2 of the coaxial cable 1 via a crimp terminal 9, and another crimp terminal 10 provided at the tip of the shield lead wire is fixed to the device frame with screws.
The frame is grounded.

[Problem to be solved by the invention]

However, in this method, the length of the coaxial wire 11 required for connection is exposed between the coaxial cable 1 and the connector case 5, which reduces the effectiveness of the overall cable shield 2 of the coaxial cable.

In addition, the exposed part of this coaxial wire 11 is generally 20 cm.
If it is made shorter than this, the cable loses its flexibility and connection operations become difficult.

Therefore, the conventional coaxial cable terminal processing method has a problem in that it hinders the reinforcement of the shield required for electronic equipment.

The present invention was created in view of these points, and an object of the present invention is to provide a coaxial cable and a terminal processing method that are effective in shielding.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides each coaxial strand of a coaxial cable with a dual shielding structure in which the center conductor has a primary shield layer and a secondary shield layer.

On the other hand, connector terminals for connecting the center conductor and the primary shield layer to the rear part by soldering are arranged in the molded body so that the tips of the terminals can be inserted into and removed from the connector on the apparatus side.

The connector is housed and fixed in the opening of a box-shaped connector case made of metal material.

The secondary shield layer 23 of the coaxial wires is exposed and aligned within the connector case, and the secondary shield layer is pressed into contact with the bottom surface of the case using a cable clamp made of a metal plate.

A pair of clamp plates made of metal plates, which are U-shaped when viewed from the front and whose end faces on the device frame side are bent tongues, are sandwiched and tightly attached to the outer surfaces of the connector case, facing each other.

The bent tongue piece is configured to come into elastic contact with the device frame while the connector case is fixed to the device frame using device fixing screws.

[Effect]

According to the present invention, the center conductor and the primary shield layer are exposed at the part where the coaxial wire and the connector terminal are connected, but this connection part is covered with a connector case made of a metal material and is shielded. has been done.

Further, the secondary shield layer of each coaxial wire is connected to the connector case by a cable clamp made of a metal material, and the bent tongue piece of the clamp plate that is in close contact with the connector case is in elastic contact with the device frame.

Therefore, coaxial cables, connector cases,
Ensure that the equipment frame is grounded.

Therefore, there is little possibility that the coaxial strands will cause electromagnetic interference, and there is also little possibility that radio waves will be radiated from the joint between the coaxial cable and the connector, or that electromagnetic noise will invade the center conductor.

〔Example〕

The present invention will be specifically described below with reference to the drawings.

FIG. 3 is a cross-sectional view of a coaxial cable with a double shield structure according to an embodiment of the present invention, and FIG. 4 is a diagram of the terminal portion of the cable according to an embodiment of the present invention.
B is a plan view, and FIG. 5 is a configuration diagram of a connector portion of an embodiment of the present invention.

The coaxial cable 21 according to the present invention has a large number of coaxial strands 31 bundled together and covered with a cable jacket made of an insulator to have a circular cross section. Therefore, unlike the conventional coaxial cable shown in FIG. 1, this coaxial cable 21 is not provided with an entire cable shield.

Each coaxial wire 31 of the coaxial cable 21
The outside of the center conductor 24 is covered with a primary shield layer 22 via an insulator, the outside of the primary shield layer 22 is covered with an insulator, and the outside of this insulation coating is further covered with a secondary shield layer 23, The outer peripheral surface of the secondary shield layer 23 is covered with a wire sheath made of synthetic resin.

Therefore, even if the cable sheath of the coaxial cable 21 is peeled off to expose the coaxial wire 31, there is no risk of interference due to radio wave radiation, and there is also no risk of causing electromagnetic interference between the coaxial wires. There is no.

On the other hand, the connector 61 has almost the same shape as the connector 6 shown in FIG. They are arranged in a substantially rectangular parallelepiped molded body so that they can be inserted into and removed from the connector.

Reference numeral 62 is a box-shaped connector case made of metal, such as steel, with open front and rear sides, and is symmetrical and partitioned into left and right sides by a partition member provided at the center.

The connector 61 is inserted and housed in the opening of the connector case 62 on the device side, and is fixed to the connector case 62 by screwing.

Further, the upper opening surface of the connector case 62 is
It is covered by a lid made of a metal plate that is screwed on.

Immediately before pulling into the connector case 62, the cable sheath of the coaxial cable 21 is peeled off to expose the coaxial wire 31, and the coaxial wire 31 is divided into two groups.
Each is drawn into the left and right chambers of the connector case 62, and the respective primary shield layer 22 and center conductor 24 are connected to the connector terminals of the corresponding connector 61 by soldering.

Then, as shown in FIG. 4, each of the coaxial strands 3 drawn into the connector case 62
The outer sheath of the first wire is peeled off and aligned, and a shallow inverted U-shaped cable clamp 81 made of a metal plate is placed on the cable clamp 81 so as to bridge the wire. Then, the cable clamp 81 is fixed to the case bottom 32 using the screw 33, each coaxial wire 31 is pressed against the case bottom 32 in a close state, and each secondary shield layer 23 is connected to the connector case 62. ing.

Reference numerals 63 and 64 shown in FIG. 5 are clamp plates that are made of springy metal plates such as stainless steel and have a U-shape when viewed from the front.

Bent tongue pieces 68 are provided on the end faces of the clamp plates 63 and 64 on the apparatus frame side, respectively.

The clamp plates 63 and 64 are clamped by left and right side plates on the left and right outer surfaces of the connector case 62 on the side where the connector 61 is inserted, due to their spring properties.
It is held in close contact with the connector case 62.

Note that the end face of the clamp plate 63 opposite to the bent tongue piece 68 is bent inward to form flanges 63a and 63b that fit into and engage grooves 65 provided on the outer circumferential surface (outer circumferential surface including the lid) of the connector case 62. is provided to prevent the clamp plate 63 from shifting. Similarly, a groove 65 is formed on the outer peripheral surface of the connector case 62 by bending the end surface of the clamp plate 64 opposite to the bent tongue piece 68 inward.
Flanges 64a and 64b that fit into and engage with the clamp plate 64 are provided to prevent the clamp plate 64 from shifting.

After the connector 61 as described above is inserted into the device side connector, the device fixing screw 66 is inserted into the hole provided in the partition member of the connector case 62, and the connector case 62, that is, the connector 61 is attached to the device frame. It's stuck.

At this time, the bent tongue piece 68 is configured to have such a relational dimension that it comes into elastic contact with the device frame.

〔Effect of the invention〕

As explained above, each coaxial wire of the coaxial cable has a double-shield structure, so even if the cable jacket is peeled off, there is no fear that the coaxial wires will cause electromagnetic interference with each other. , the connection between the coaxial cable and the connector is covered by the connector case, and the secondary shield layer and the connector case are grounded to the device frame via the clamp plate, so radio waves may be emitted from the connection, or This has excellent practical effects, such as less fear of electromagnetic noise entering the center conductor.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a conventional coaxial cable, Fig. 2 is a perspective view of a connector connection part of a conventional example, Fig. 3 is a cross-sectional view of a coaxial cable according to an embodiment of the present invention, and Fig. 4 is a cross-sectional view of a coaxial cable according to an embodiment of the present invention. FIG. 5 is a diagram of the terminal portion of the cable in the example, in which A is a sectional view, B is a plan view, and FIG. 5 is a configuration diagram of a connector portion of an embodiment of the present invention. In the figure, 1 and 12 are coaxial cables, 3 and 2
4 is a center conductor, 4 is a shield layer, 5, 62 are connector cases, 6, 61 are connectors, 7, 66 are device fixing screws, 8, 81 are cable clamps, 1
1 and 31 are coaxial wires, 22 is a primary shield layer, 2
3 is the secondary shield layer, 32 is the bottom of the case, 63,
Reference numeral 64 indicates a clamp plate, and reference numeral 68 indicates a bent tongue piece.

Claims (1)

[Scope of Claims] 1. In a device configured to connect electronic devices with a coaxial cable by attaching a connector to the terminal of a multicore coaxial cable having a large number of coaxial strands, each coaxial strand 31 However, a primary shield layer 22 and a secondary shield layer 23 are provided outside the center conductor 24.
A multi-core coaxial cable 21 with a double shield structure provided with a connector terminal, which connects the center conductor 24 and the primary shield layer 22 by soldering, is molded so that the tip side can be inserted into and removed from the connector on the device side. A box-shaped connector case 62 made of a metal material that accommodates and fixes the connectors 61 in the opening, and the coaxial wires 31 are aligned in the connector case 62 and exposed. A cable clamp 81 made of a metal plate brings the secondary shield layer 23 into pressure contact with the case bottom 32, and the end face on the device frame side serves as a bent tongue piece 68.
A pair of clamp plates 63 and 64 made of metal plates, which are U-shaped in front view and are clamped and tightly attached to the outer surface of the connector case 62, respectively, are provided, and the connector is fixed using mounting and fixing screws 66. A coaxial cable termination method characterized in that the bent tongue piece 68 comes into elastic contact with the device frame while the case 62 is fixed to the device frame.