JP3394078B2 - Connection structure of conductor terminals for connection - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a connecting structure of connecting conductor terminals used in a cable head or the like for connecting a cable line and equipment.

[0002]

2. Description of the Related Art Conventionally, GIS (gas insulated switchgear)
As a cable head for connecting a cable line with a high voltage device such as the one having a structure as shown in FIG. 5, for example, is known.

That is, in this cable head, the electrical connection between the cable line 1 and the internal circuit of the device is such that the internal electrode 4 embedded in the central portion of the bushing 3 attached to the wall surface 2 of the device and the projection thereof. It is performed through the conductor pull-out rod 5 embedded in the portion (device side). Furthermore, in detail, one end of the conductor pull-out rod 5 is connected to the internal circuit of the device, and the other end thereof is electrically connected to the internal electrode 4 via a substantially conical connecting conductor terminal 7. It should be noted that spring-shaped contacts 6 having spring properties in the radial direction are attached to both ends on the outer circumferences of both ends of the connecting conductor terminal 7, and the conductor-drawing rod 5,
The connecting conductor terminal 7 and the internal electrode 4 are electrically connected. The internal electrode 4 is connected via a tulip contact 8 to a conductor terminal 9 attached to the conductor end of the end of the cable line 1. In addition, in FIG. 5, 10 has shown the electricity application terminal part for connecting the cable for electricity application. 6 (a) and 6 (b) show the structure of the spring-shaped contactor 6, in which the annular conductive leaf spring 6a is provided with a large number of cuts 6b parallel to the axial direction and a plurality of ends are connected to each other. The bridge pieces 6c are formed, and the bridge pieces 6c are twisted around the center line in the longitudinal direction as an axis to provide a spring property in the radial direction.

[0004]

By the way, in such a cable head, sufficient ground fault characteristics cannot be obtained at the connecting portion of the connecting conductor terminal 7, and when a ground fault test is conducted, the desired result is obtained. There is a problem that melting loss occurs under conditions much lower than the ground fault capacity.

Therefore, the present inventor has conducted earnest research to elucidate the cause of such a decrease in the ground fault capacity, and as a result, melting damage due to the ground fault test has occurred at the tip surface of the connecting conductor terminal 7. As enlarged and shown in FIG. 7, it has been found that there is a problem in the connecting structure in which the leading end surface of the connecting conductor terminal 7 is inserted until it comes into contact with the bottom surface 5a of the receiving hole of the conductor pull-out rod 5. That is, when the connecting conductor terminal 7 and the conductor pull-out rod 5 are in contact with each other at a portion other than the spring-shaped contactor 6 as described above,
As shown by the arrow in the figure, since the current is shunted to the contact portion, the spring contact 6 itself has a sufficient current capacity when a large current such as a ground fault current flows. However, since the contact resistance is high in other contact portions, heat is generated and the metal in the portion melts.

The present invention has been made on the basis of such knowledge, and prevents melting damage at the tip of the connecting conductor terminal.
It is an object of the present invention to provide a connection structure of a conductor terminal for connection, which can substantially increase the ground fault capacity and can be used to obtain a connection device such as a cable head having excellent electrical characteristics.

[0007]

SUMMARY OF THE INVENTION According to the present invention, a connecting conductor terminal is provided in the receiving hole of a connecting conductor having a receiving hole for receiving the tip of the connecting conductor terminal. In a connection structure of a connecting conductor terminal, which is detachably inserted through a spring-shaped contactor fitted to an inner peripheral surface of the receiving hole of the connecting conductor, a tip surface of the connecting conductor terminal and the receiving hole Between the bottom and the front of the connecting conductor terminal
A void is formed by preventing movement toward the receiving hole, and the connecting conductor terminal and the connecting conductor are electrically connected only by the spring contact.

In the present invention, the voids are
An insulating spacer may be interposed, and in this case, the non-contact state between the tip end surface of the connecting conductor terminal and the bottom surface of the receiving hole of the connecting conductor can be reliably formed and held, which is more advantageous.

[0009]

In the connection structure of the connection conductor terminal of the present invention, the gap between the tip end surface of the connection conductor terminal and the bottom surface of the receiving hole of the connection conductor is made non-contact by the formation of the void. Even if a large current such as a leak current is generated, the tip of the connecting conductor terminal is not melted and the grounding capacitance of the connecting conductor terminal can be substantially increased.

Further, when the insulating spacer is interposed in the gap, the non-contact state can be surely formed and held, so that the reliability is improved and the assembly is easy.

[0011]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

In FIG. 1, 11 is a rod-shaped conductor, and 12 is a connection conductor having a receiving hole 13 for receiving the tip of the rod-shaped conductor 11. A concave groove 13a is provided in the inner peripheral surface of the receiving hole 13 of the connecting conductor 12 in the circumferential direction. In the concave groove 13a, a band-shaped contactor made of beryllium or the like as shown in FIG. Is fitted along the inner wall of
As a result, the spring-like contactor 14 is provided with a spring property in the radial direction. In the figure, 14a represents a stop ring made of brass or the like for fixing the band-shaped contactor. Then, the rod-shaped conductor 11 is plugged into the receiving hole 13 of the connecting conductor 12, and the tip end surface thereof is plugged into the spring-shaped contactor 14 arranged in a ring shape.
The rod-shaped conductor 11 and the connection conductor 12 are electrically connected by being inserted to a position reaching the vicinity of 2a. Note that FIG.
FIG. 3 illustrates a state before the rod-shaped conductor 11 is attached to the connection conductor 12.

In such a connection structure, the tip end surface of the rod-shaped conductor 11 and the bottom surface 12a of the receiving hole 13 of the connection conductor 12 are connected.
Since the gap G is formed between them, the rod-shaped conductor 11 and the connection conductor 12 are mechanically and electrically connected only by the spring-shaped contactor 14. Therefore, even if a large current such as a ground fault current may flow between the rod-shaped conductor 11 and the connection conductor 12, the current flows only through the spring-shaped contactor 14, that is, the tip portion of the rod-shaped conductor 11 Since there is no possibility of shunting, the tip end surface of the rod-shaped conductor 11 will not be melted and the ground fault characteristic will be improved.
By the way, in the connection structure having the above configuration, the rod-shaped conductor 11
A ground fault test was conducted in which a direct current of 20 kA, 25 kA, 31.5 kA, and 40 kA was passed between the connection conductor 12 and the connecting conductor 12 for 2 seconds, respectively. On the other hand, when a similar ground fault test was carried out on a conventional structure having no gap G between the tip end surface of the rod-shaped conductor 11 and the bottom surface 12a of the receiving hole 13 of the connection conductor 12, a current of 20 kA was applied to the rod-shaped conductor 11. Melting occurred.

The embodiment described above is an example of a connection structure in which the rod-shaped conductor 11 is inserted into the connection conductor 12 in which the spring-shaped contactor 14 is fitted in advance. As shown in FIG. 3, a concave groove 11a is provided in the circumferential direction on the outer peripheral surface of the end portion of the rod-shaped conductor 11, and the spring-shaped contactor 14 fitted into the concave groove 11a is inserted into the connection conductor 12. The connection structure may be configured, and the rod-shaped conductor 11
The same effect can be obtained by forming the gap G between the tip surface of the above and the bottom surface 12a of the receiving hole 13 of the connection conductor 12. 3A shows a state before the rod-shaped conductor 11 is inserted into the connection conductor 12, and FIG. 3B is a cross-sectional view of the main part thereof, in which the groove 11a of the rod-shaped conductor 11 is spring-loaded. It shows a state in which the linear contactor 14 is fitted. The spring contact 14 is fixed in the groove 11a by utilizing its elastic deformation.

In the above embodiment, the gap G is formed between the tip end surface of the rod-shaped conductor 11 and the bottom surface 12a of the receiving hole 13 of the connecting conductor 12, but in the present invention, a ceramic is provided between them. Alternatively, an insulating spacer made of epoxy resin or the like may be interposed to prevent contact between the two. The insulating spacer does not have to completely fill the gap G, and a ring-shaped one can be used. The insulating spacer may be fixed in advance to the tip end surface of the rod-shaped conductor 11 or the bottom surface of the receiving hole 13 of the connection conductor 12, or may be inserted during assembly.

Next, another embodiment of the present invention will be described. That is, FIG. 4 is a vertical cross-sectional view showing a main part of a device connection cable head to which the connection structure of the connection conductor terminal of the present invention is applied.

Although not shown in FIG. 4, reference numeral 15 denotes a bushing made of an insulating resin such as an epoxy resin, which is attached to the wall surface of the equipment, and is connected to the internal circuit of the equipment. Conductor withdrawal bar 16
The internal electrodes 17 connected to the cable lines (not shown) are embedded. The conductor lead-out rod 16 and the internal electrode 17 have a cylindrical small-diameter portion 20 in which spring-shaped contacts 19 are provided on the outer circumferences at both ends of the tapered portion 18, respectively.
And a cylindrical large-diameter portion 21, and is electrically connected by a detachable rod-shaped connecting conductor terminal 22 for connection. That is, between the conductor pull-out rod 16 of the bushing 15 and the internal electrode 17, a tapered hollow portion 23 having a shape corresponding to the tapered portion 18 of the connecting conductor terminal 22 that expands toward the internal electrode 11 side is provided. The cylindrical small diameter portion 20 of the connecting conductor terminal 22 communicating with the tapered hollow portion 23 of the conductor pull-out rod 16.
Is provided with a connecting conductor terminal receiving hole 24. The connecting conductor terminal 22 has a cylindrical small-diameter portion 20 as a connecting conductor terminal receiving hole 24 and a tapered portion 18 as a tapered hollow portion 23. Further, the tubular large-diameter portion 21 is fitted and mounted in the through hole 25 of the internal electrode 15. A gap G is provided between the cylindrical small-diameter portion 20 fitted in the connecting conductor terminal receiving hole 24 and the connecting conductor terminal receiving hole 24, and the receiving end of the cylindrical small-diameter portion 20 is received. The structure prevents direct contact with the holes 24. Note that reference numeral 26 denotes a fixing fitting screwed into the through hole 25 of the internal electrode 17 for fixing the connecting conductor terminal 22.

Below the through hole 25 of the internal electrode 17, there is provided a cable end insertion hole 27 into which the end of the cable line is inserted, and a conductor terminal 29 is connected to the conductor end portion 28. The cable end is inserted, and the conductor terminal 29 is inserted into the tulip contact 31 attached to the boss 30 projecting to the center of the bottom of the cable end insertion hole 27, whereby the internal electrode 17 and the cable line are electrically connected. Tei Ru.

In FIG. 4, numeral 32 indicates a blind plug,
When conducting a power application test, a power supply cable can be connected to the blind plug 32 instead of the blind plug 32.

In such a structure, since the gap G is provided between the tip end surface of the connecting conductor terminal 22 and the bottom surface of the connecting conductor terminal receiving hole 24 of the conductor pull-out rod 16,
Similar to the case of the embodiment described above, the connecting conductor terminal 22 is used.
Even if a large current such as a ground fault current may flow between the lead wire 16 and the conductor pull-out rod 16, the tip of the connecting conductor terminal 22 is not melted due to the shunt of the current, and the ground fault capacity is improved. .

The tapered hollow portion 2 of the bushing 15 is also provided.
Since the tapered portion 18 of the connecting conductor terminal 22 is fitted to the connector 3, the movement of the connecting conductor terminal 22 toward the conductor pull-out bar 16 is prevented, so that the assembly is easy and once formed. The void G does not disappear, and stable ground fault characteristics can be obtained.

[0023]

[0024]

As described above, in the present invention, melting damage of the tip end portion of the connecting conductor terminal can be prevented, and the ground fault capacitance of the connecting conductor terminal can be substantially increased.

[Brief description of drawings]

FIG. 1 is a sectional view showing a main part of an embodiment of the present invention.

FIG. 2 is a cross-sectional view showing a state before assembly.

FIG. 3 is a sectional view showing a state before assembly of another embodiment.

FIG. 4 is a vertical cross-sectional view showing a main part of a device connection cable head to which the connection structure of the connection conductor terminal of the present invention is applied.

FIG. 5 is a vertical cross-sectional view showing an example of a connection structure of connection conductor terminals in a conventional cable head.

FIG. 6 is a perspective view showing the structure of a spring contact.

FIG. 7 is an enlarged view of a main part of a connection structure example of a conventional connection conductor terminal.

[Explanation of symbols]

11 ………… Rod-shaped conductor 12 ......... Connecting conductor 12a ......... bottom of receiving hole 13 ... Receiving hole 14, 19 ... Spring-shaped contacts 15 ... Bushing 16 ... Conductor lead-out rod 17 ......... Internal electrode 22 ......... Conductor terminal for connection 24: Connection conductor terminal receiving hole 29 ... Conductor terminals 31 ……… Tulip contact

─────────────────────────────────────────────────── ─── Continuation of front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) H01R 4/48 H02G 15/02 H02G 15/06

Claims (2)

(57) [Claims] 1. An outer peripheral surface of the connecting conductor terminal or an inner periphery of the receiving hole of the connecting conductor, wherein the connecting conductor terminal has the receiving hole of the connecting conductor having a receiving hole for receiving the leading end of the connecting conductor terminal. in the connection structure of the connection conductor terminal via a spring-like contacts which is fitted to the surface detachably formed by inserted, between the front end surface of the connection conductor terminal and the bottom surface of the receiving hole, the connecting The movement of the conductor terminal for use toward the receiving hole.
A connection conductor terminal connecting structure, characterized in that a void portion is formed by preventing the connection conductor terminal and the connection conductor are electrically connected only by the spring contact. 2. A conductor terminal for connection, wherein the conductor terminal for connection is
Said receiving hole of a connecting conductor having a receiving hole for receiving a tip
The outer peripheral surface of the connection conductor terminal or the connection conductor
Attaching / detaching via a spring-like contact fitted on the inner peripheral surface of the receiving hole.
In the connection structure of the connecting conductor terminal that is inserted in the Between the tip surface of the connecting conductor terminal and the bottom surface of the receiving hole
A void is formed in the space, and an insulating spacer is interposed in the void.
The connecting conductor terminal and the connecting conductor are
Characterized by being electrically connected only by contacts
And the connection structure of the conductor terminals for connection.