JPH08149674A - Termination of cable - Google Patents

Abstract

PURPOSE: To reduce the overall size of a cable terminal and to enhance the worke by decreasing the inserting/drawing force thereof. CONSTITUTION: An inner electrode 23 is provided above a bushing and in order to secure a connection terminal 31, for connecting the conductor 4 of a cable 1 electrically with the inner electrode 23 and suspending the cable 1, to the inner electrode in a connection hole opening to the lower part thereof, a projecting ball 39, inner and outer positioning pipes 37, 36, etc., are employed. The connection terminal 31 and an adapter 32 can be slipped easily onto the inner electrode 23 and prevented from removing after connection by means of the projecting bal 39 and the like thus preventing the cable 1 from slipping.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cable end connecting portion formed at a connecting portion between a cable and a device or a rising end of the cable.

[0002]

2. Description of the Related Art At the end of a high-voltage cable, a terminal using a bushing is formed in order to protect an electric connection portion with equipment or the like. FIG. 2 shows a vertical sectional view of a conventional general cable terminating connection portion. In the figure, in a cable 1, a jacket 2 and an insulator 3 are peeled off in order to expose a conductor 4, and a connection terminal 5 is compression-connected to the conductor 4. The cable 1 is inserted from the lower part of the bushing 6 and is terminated inside this. The bushing 6 is formed by molding an insulator or epoxy resin, and an internal electrode 7 made of copper or the like is provided inside the upper portion. The tulip contact 9 is arranged inside the internal electrode 7, and the connecting terminal 5 of the cable described above is electrically connected via the tulip contact 9 at the lower end of the conductor withdrawing rod 8 protruding upward from the top of the bushing 6. Has been done. The conductor lead-out rod 8 is fixed to the bushing 6 by the upper metal fitting 10 above the internal electrode 7. A cylindrical corona shield 15 is arranged so as to be supported by the upper metal fitting 10 in order to prevent corona generation around the upper metal fitting 10 and the conductor withdrawing rod 8.

When such a bushing 6 is arranged inside the wall surface of the equipment and the cable 1 is connected to the internal circuit of the equipment (not shown), the tip of the conductor drawing rod 8 is surrounded by the one-dot chain line in the figure. A battledore-shaped connecting plate 8A as shown in circle A is provided. A stress cone 11 is fitted in the insulator 3 of the cable 1 and is pressed against the inner wall surface of the lower portion of the bushing 6 with a predetermined pressure by using a pressing metal fitting 12 and a spring unit 13.

[0004]

By the way, the above-mentioned conventional cable terminal connecting portion has the following problems to be solved. When the cable terminating connection portion as described above is attached to a portion having a relatively small space, such as an inner wall surface of a device, it is preferable that the cable terminating portion be as small as possible. Moreover, it is preferable that the assembling work is easy. However, in order to insert the above cable end into the tulip contact, a pressing force of, for example, about 40 kg is required, and when pulling out, a pulling force of about 300 kg is required. This imposes a heavy burden on the worker, and the workability is poor. The present invention has been made in view of the above points, and it is possible to provide a cable termination connecting portion that enables downsizing of the entire termination and further reduces the insertion / extraction force of the cable termination to improve workability. It is intended.

[0005]

SUMMARY OF THE INVENTION The cable termination connection of the present invention comprises a bushing for receiving the cable termination and an internal electrode within the bushing that is electrically connected to a conductor of a cable inserted from the base of the bushing. The internal electrode is provided with a connection terminal for receiving and electrically connecting the end of the conductor for external circuit inserted from the opening of the top of the bushing, and the conductor tip of the cable inserted from the base of the bushing has an internal A connection terminal that is inserted into the connection port opened on the bottom surface of the electrode is fixed, and when this connection terminal is inserted into a fixed position of the connection port, a protrusion is projected toward the wall surface of the connection port to disconnect the connection terminal. It is characterized in that a projection projecting / retracting mechanism for preventing the above is provided.

[0006]

Function: An internal electrode is provided on the upper part of the bushing, and an internal connection hole is provided at the lower part of the bushing to provide an electrical connection between the conductor of the cable and the internal electrode and a connection terminal for suspending the cable. To fix to the electrode,
A projecting ball and an inner pipe or an outer pipe for positioning the projecting ball are used. The connection terminal and the adapter can be easily and lightly inserted into the internal electrode in a slip-on manner, and after the connection is completed, the projecting ball or the like prevents the cable from slipping off and prevents the cable from slipping off.

[0007]

The present invention will be described in detail below with reference to the embodiments shown in the drawings. FIG. 1 is a longitudinal sectional view of a main part showing an embodiment of a cable terminating connection part of the present invention. Before describing the configuration of this figure, first, a schematic configuration of the entire cable connecting portion of the present invention will be described with reference to FIG.
Will be explained. In FIG. 3, the cable 1 has the outer cover 2 and the insulator 3 peeled off to expose the conductor 4 at the end. Connection terminals and the like, which will be described later with reference to FIG. 1, are attached to the conductor 4, and these are inserted into the connection holes 23A of the internal electrodes 23 arranged inside the bushing 20.
A protective fitting 25 is fixed to the lower portion of the bushing 20 to protect the end portion of the cable 1 together with the seal 26 from water. Further, the stress cone 11 fitted into the insulator 3 is configured to be pressed against the inner wall surface of the bushing 20 with an appropriate pressure by the spring 22A and the pressing metal member 22 mounted on the upper surface of the protective metal member 25.

The internal electrode 23 disposed inside the bushing 20 is provided with a male projection 23D on the upper portion thereof. The male protrusion 23D is fitted into the female end portion of the external circuit conductor 24 drawn from the circuit of the device or the like. On the outer peripheral surface of the male protrusion 23D, a contactor 23C that enhances electrical contact and enables slip-on connection is arranged. This is an arrangement in which various types of ribbon-shaped leaf spring assemblies are arranged on the circumference and is widely used for this type of electrical connection. This has the same structure as a contactor attached to a connection terminal or the like of a cable described later.

In the cable terminating connection portion of the present invention having the configuration shown in this figure, the cable is inserted from below, and the electrical connection is completed by the slip-on type connection. Further, the external circuit conductor 24 can be connected to the upper portion by a similar slip-on type connection. Therefore, the end can be assembled by a relatively simple connecting operation. In such a configuration, it is preferable that the weight of the cable is supported by the conductor 4. Therefore, in the present invention, the terminal structure as shown in the one-dot chain line circle B is adopted.

FIG. 1 shows a detailed sectional view of the terminal structure. In the illustrated cable 1, the conductor 4 is exposed for a predetermined length from the end of the insulator 3, and the connection terminal 31 is compression-connected thereto. On the outer peripheral surface of the upper portion of the connection terminal 31, the contactor 33 for reducing the electrical contact resistance at the time of slip-on connection or the like is arranged as described above. This connection terminal 31
The adapter 32 is fitted on the outside so that the adapter 32 just fits on the outside. That is, the connection terminal 31 is fitted into the through hole provided in the shaft portion of the adapter 32, and the tip of the connection terminal 31 slightly projects from the adapter 32 so that the two do not come off.
The mold stop ring 35 is fitted. This has the same structure as a C ring which is well known as a mechanical part.

The adapter 32 is made of a cylindrical conductor having a thick upper portion and a thin lower portion, and a female screw portion 32A is formed on the inner surface of the lower end. On the other hand, below the adapter 32, a protrusion retracting mechanism including an outer pipe 36, an inner pipe 37, a spring 38, a projecting ball 39 and the like is provided. A male screw portion 36A is formed on the outer periphery of the upper end of the outer pipe 36, and is screwed into the female screw portion 32A of the adapter 32 to connect them. Also, the outer pipe 3
A step portion 36B is formed on the inner surface of the upper portion of 6.

The spring 3 is provided between the step 36B and the step 37B provided at the center of the inner pipe 37.
8, the spring 38 pushes the outer pipe 36 upward and the inner pipe 37 downward. The outer pipe 36 is provided with several ball storage holes 36C in the lower part thereof. A projecting ball 39 is housed in the ball housing hole 36C. The projecting ball 39 is made of a steel ball or the like, and the outer diameter is selected so that a part of the projecting ball 39 projects outward from the ball storage hole 36C. Further, a receiving groove 37C for receiving a part of the projecting ball 39 is provided on the outer peripheral surface of the inner pipe 37 as described later.

Further, the projecting ball 39 is provided with a ball storage hole 36.
When protruding outward from C, the internal electrode 23 is provided with a positioning groove 23B so as to receive the protruding portion. That is, in the state shown in this figure, the protruding ball 3
Reference numeral 9 indicates a part of the outer pipe 36 protruding from the ball storage hole 36C to the outside, and a part thereof projects into the positioning groove 23B. The adapter 32 slides up and down with respect to the inner wall surface of the connection hole of the inner electrode 23. Be blocked. That is, the connection terminal 31 is prevented from coming off.

The tip or upper end of the stress cone 11 fitted on the outer peripheral surface of the cable 1 is provided with a stopper 17
To push the flange portion 37D of the inner pipe 37 against the lower end surface of the internal electrode 23. The position of the inner pipe 37 is determined by this force as shown in the figure. In this state, the projecting ball 39 stored in the ball storage hole 36C of the outer pipe 36 is pushed outward by the outer wall surface of the inner pipe 37, The portion projects into the positioning groove 23B.

FIG. 4 illustrates the state of the cable terminal before positioning the connection terminal at the fixed position of the connection hole as described above. Before completing the cable end assembly, stress cone 1
There is a gap between 1 and the bushing 20, and the inner pipe 37 is still below the home position. When forming such an end, first, the connection terminal 31 is compressed and connected to the conductor 4 of the cable, then the inner pipe 37 is fitted, the spring 38 is fitted on the outer side thereof, and the outer pipe 36 is further arranged on the outer side thereof. Cover. Next, the upper end of the inner pipe 37 is projected onto the outer pipe 36 while compressing the spring 38. Then, the retaining ring 41 is fixed to the upper end of the inner pipe 37 to prevent the two from coming off.

At this time, the projecting balls 39 are formed on the outer pipe 36.
The ball storage hole 36C and the receiving groove 37C of the inner pipe 37 are stored. Therefore, the entire protruding ball 39 is the outer pipe 3
6 is located inside the outer peripheral surface and is not projected to the outside. Here, finally, the adapter 32 is screwed into the outer pipe 36, and the tip of the connection terminal 31 is projected from the adapter 32.
When the C-shaped stop ring 35 is fitted, the assembly of the terminal portion is completed. Then, the adapter 32 is inserted into the connection hole of the internal electrode 23 in the state as shown in FIG. In this case,
Since the projecting ball 39 does not project to the outside, the adapter 32 is completely housed in the connection hole of the internal electrode 23 as shown in the figure.

In this state, the projecting ball 39 is arranged so as to face the positioning groove 23B. Here, the stress cone 11 shown in FIG. 3 is replaced with the spring 2 shown in FIG.
When pushed using 2A or the like, the flange portion 37D of the inner pipe 37 is pushed upward via the stopper 17. As a result, the protruding ball 39 is pushed out from the receiving groove 37C,
It is pushed by the outer wall surface of the inner pipe 37, and a part thereof is projected to the positioning groove 23B side. In this way, the projecting ball 39 positions the adapter 32 and the like in the state as shown in FIG. 1, whereby the cable is suspended from the internal electrode 23 via the conductor 4.

As described above with reference to FIG. 3, in the cable terminating connection portion of the present invention having the above-described structure, the external circuit conductor is connected from the upper portion by a simple connection structure such as a slip-on type, and from the lower portion. Connect the cable conductors in the slip-on manner as described above. Then, the protrusion / retraction mechanism including the protrusion ball 39 and the like prevents the connection terminal from coming off,
A reliable high mechanical strength end is formed. In addition, the size of the tulip contact can be reduced as a whole. In addition, a guard ring portion 23E, which is an extension of the internal electrode 23, is formed on the bushing 20 at a portion connected to the external circuit conductor to prevent electrical protection and corona generation at this portion. This embodiment does not require the large corona shield as described in FIG.

The present invention is not limited to the above embodiments. In the above-described embodiment, the example in which the male protrusion 23D is used in the portion connected to the external circuit conductor in the upper portion of the internal electrode 23 has been shown, but this portion may have a slip-on type structure, for example. It may be a plug-in type configuration. If the cable end is a slip-on type connection as described above, the force required for insertion / removal work can be made sufficiently small and workability can be improved as compared with the conventional plug-in connection or the like. Various other well-known connection structures may be used for the other portions. Further, the projection retracting mechanism itself may have a structure in which a pin or the like is projected in addition to the structure in which the ball is projected as described above.

[0020]

In the cable terminating connection portion of the present invention described above, the connection terminal inserted into the connection hole opened to the lower surface of the internal electrode is fixed to the conductor tip of the cable inserted from the base of the bushing, and this connection is made. When the terminal is inserted in the fixed position of the connection hole, the projection is projected toward the side wall surface and the projection retracting mechanism is provided to prevent the connection terminal from coming off. The force can be reduced to facilitate workability, and a terminal having high mechanical strength that strongly supports the cable once connected can be obtained.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a main part showing an embodiment of a cable terminating connection part of the present invention.

FIG. 2 is a vertical cross-sectional view of a conventional cable termination connection portion.

FIG. 3 is a vertical cross-sectional view showing the overall configuration of a cable termination connection portion of the present invention.

FIG. 4 is a vertical cross-sectional view for explaining the assembling procedure of the cable terminating connection portion of the present invention.

[Explanation of symbols]

 1 Cable 3 Insulator 4 Conductor 11 Stress Cone 17 Stopper 23 Internal Electrode 23B Positioning Groove 31 Connection Terminal 32 Adapter 33, 34 Contact 36 External Pipe 37 Inner Pipe 37D Flange 39 Projecting Ball

Claims (1)

[Claims] 1. A bushing for accommodating a cable termination, and an internal electrode, inside the bushing, electrically connected to a conductor of a cable inserted from the base of the bushing, the internal electrode having an opening at the top of the bushing. A connection terminal for receiving and electrically connecting the end of the external circuit conductor inserted from is provided, and the conductor tip of the cable inserted from the base of the bushing is inserted into the connection opening opened to the lower surface of the internal electrode. The connection terminal is fixed, and the connection terminal is provided with a protrusion retracting mechanism that protrudes a protrusion toward the wall surface of the connection port to prevent the connection terminal from coming off when the connection terminal is inserted into a fixed position of the connection port. A cable termination connection characterized in that