JPH0799888B2 - Insulation spacer for gas insulated switchgear - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an insulating spacer used for supporting a gas section and a conductor in a gas-insulated switchgear or the like.

[Conventional technology]

FIG. 4 is a partial fragmentary sectional view showing the general structure of a gas insulated switchgear (hereinafter abbreviated as GIS). In the figure, 31A, 31B and 31C are ground metal containers of GIS, for example, the metal containers 31A and 31B are hermetically flange-bonded with the insulating spacer 1 interposed therebetween, so that the gas partition chamber defined by the insulating spacer 1 is formed. 39A and 39B are formed. The insulating spacer 1 is shown in a plan view in FIG. 5A and AA in FIG. 5B.
As shown in the sectional view in the direction, a resin mold layer 2 in which a metal flange 4 having a circular inner peripheral surface having a through hole 4B of a tightening bolt and an embedded conductor 3 are made of a cured product of an epoxy-based casting resin composition The O-ring groove 2B formed on the outer peripheral portion of the resin mold layer 2
The ring keeps confidentiality and the buried conductor 3
The charging portion of the switchgear including, for example, a large current conductor 32 electrically conductively coupled to the grounding metal container 31A, 31B, 31C and the like 31 is insulated and supported.

Further, the large current conductor 32 is, for example, a fixed contact portion of a ground switch.
33A has a movable contact 33C guided by a movable contact holder 33C provided on the side of the metal container 33A facing the movable contact 33C, which is conductively coupled to the fixed contact, thereby grounding the charging portion from the outside of the metal container. The operation is performed. Therefore, the insulating spacer 1 positions and insulates the high-voltage charging part at a predetermined position, and also has a positioning function of withstanding mechanical force generated by opening and closing of the ground switch or electromagnetic mechanical force acting on a large current conductor. Required to hold. Therefore, a U-shaped concave groove 4A is preliminarily formed on the inner peripheral surface of the metal flange 4 along the circumference thereof, and the liquid casting resin fills the U-shaped concave groove 4A during the casting operation. By hardening, the metal flange 4 firmly supports the outer peripheral portion of the resin mold layer 2 in which the embedded conductor 3 is integrated, and the storage device can be insulated and supported in a state of being positioned at a predetermined position.

[Problems to be Solved by the Invention]

In the conventional insulating spacer, since the resin mold layer 2 cures and shrinks when the resin is heated and cured, the embedded conductor 3 is tightly bound by the stress generated by the cure and shrinkage, and the airtightness is maintained at the interface between the two to strengthen the resin. Although integrated, a stress is generated between the inner peripheral surface of the metal flange 4 and the adhesive surface in the direction of peeling. Therefore, in general, the metal flange 4
A release agent is applied to the inner peripheral surface of the resin in advance to avoid local adhesion, and a treatment is performed so that no internal stress remains in the resin mold layer. Therefore, a minute gap exists between the resin mold layer 2 and the metal flange 4, absorbs the difference in thermal expansion between the resin mold layer and the metal flange, and relaxes the thermal stress generated in the resin mold layer. However, since this gap allows the resin mold layer to rotate in the circumferential direction, there arises a problem that the positioning function for regulating the circumferential position of the large current conductor connected through the embedded conductor cannot be obtained. As a means for eliminating such a problem, it is known to use the protrusion 2A protruding from the resin mold layer toward the injection port of the casting resin penetrating the metal flange 4 to prevent the resin mold layer from rotating around the metal flange 4. Has been. However, the use of only one protrusion in the circumferential direction is not sufficient to suppress the rotation of the resin mold layer, and the external force applied during the assembly work and the mechanical force applied to the large current conductor after the assembly work. The protrusion 2A is often cut off and the detent function deteriorates, and when the protrusion 2A comes off the root, the detent function may be lost and the flange 4 and the embedded There is a problem that the positional relationship with the conductor 3 in the circumferential direction becomes uncertain.

An object of the present invention is to provide a rotation preventing means that can stably maintain a relative position in the circumferential direction of each other without causing thermal stress between the metal flange and the resin mold layer.

[Means for Solving the Problems]

In order to solve the above problems, according to the present invention, a metal flange having a U-shaped groove along the inner peripheral surface and an embedded conductor are integrally resin-molded with an epoxy-based casting resin composition. An opening / closing connected to the embedded conductor while an outer peripheral portion of the resin mold layer including the metal flange is hermetically sandwiched between the flanges of adjacent ground metal containers of the gas insulated switchgear to form a gas compartment. In a device for insulating and supporting a charged part of a device, it comprises a recess formed in a plurality of circumferential U-shaped concave grooves and a protrusion formed in a resin mold layer so as to fill the recess. It is assumed that the resin mold layer has a rotation preventing portion which is separated from the flange and has a gap.

[Action]

In the above means, a mold releasing agent is applied to the U-shaped concave groove of the metal flange to form a plurality of depressions distributed in the circumferential direction in advance. By forming a protrusion that engages with the recess in the resin mold layer after being filled and heat-cured, a whirl-stop is formed by the recess and the protrusion, and thermal stress is generated between the resin mold layer and the metal flange. It is possible to obtain a whirl-stop function that prevents rotation of the resin mold layer by leaving a gap that avoids the occurrence of

〔Example〕

 The present invention will be described below based on examples.

1A and 1B are a plan view and a side cross-sectional view of an insulating spacer showing an embodiment of the present invention, and FIG. 2 is an enlarged cross-sectional view of the main part thereof, and the same reference numerals are given to the same parts as those in the prior art. Detailed description is omitted by using. In the figure,
20A, 20B, and 20C are anti-rotation parts, and the half-moon shaped dents 21 formed in three places are distributed in the circumferential direction at the bottom of the U-shaped concave groove 14A of the metal flange 14 and the epoxy casting resin. Casting,
The resin mold layer (12) is formed with a half-moon shaped protrusion (22) corresponding to the depression (21) on the outer periphery of the resin mold layer (12) by heat curing.

In the embodiment insulating spacer thus configured, the concave groove portion of the metal flange 14 is treated with a release agent, and therefore the outer peripheral surface of the resin mold layer 12 including the protrusion 22 due to the curing shrinkage of the resin mold layer 12 and the metal. When the resin mold layer 12 thermally expands due to a temperature rise caused by a current flowing through the embedded conductor 3 and a large current conductor connected to the embedded conductor 3 when a gap having a gap length g is formed between the metal flange 14 and the flange 14. The gap length g absorbs the difference in thermal expansion between and to avoid occurrence of thermal stress. On the other hand, when the insulating spacer is airtightly sandwiched between the flanges of the grounded metal containers 31A and 31B as already described with reference to FIG. 4, and the large current conductor 32 or the like is connected to the embedded conductor 3,
The width W of the metal flange 14 is the resin mold layer.
It is held by being formed slightly larger than the thickness of 12, and the resin mold layer 12 comes into a state of airtightly contacting the flange surface of the grounded metal container through the O-ring 2B.
The resin mold layer 12 can be rotated with respect to the metal flange 14 by using the sealing surface of the O-ring as a sliding surface.
Rotation is suppressed within the range of the gap length g by the recess 21 of 20 and the protrusion 22 engaging with this. Therefore, rotation of the large current conductor connected to the resin mold layer 12 through the embedded conductor 3 is suppressed.

FIG. 3 is a partially crushed sectional view showing an essential part of a different embodiment of the present invention, showing a state of the resin mold layer as viewed from the outer peripheral surface side thereof. In the figure, the protrusions 22A, 22B
Is formed in a half-moon shape that is convex to the side of the width w _{1 in} a portion that fits into the U-shaped groove having the width w ₁ of the resin mold layer 12, and a protrusion is formed on the side wall side of the groove 14A of the metal flange 14. By forming a recess (not shown) corresponding to 22A and 22B, a rotation stop portion is formed. When the anti-rotation part is configured in this way, the width w ₁
Is smaller than the diameter of the resin mold layer 12, the gap length g caused by curing shrinkage can be made smaller than that of the above-described embodiment, so that a more accurate anti-rotation function can be obtained.

〔The invention's effect〕

As described above, according to the present invention, the depression is formed in advance in the U-shaped groove of the metal flange, and the corresponding resin mold layer side is formed by casting, and is released from the metal flange. A plurality of anti-rotation parts composed of protrusions are distributed in the circumferential direction and provided at a plurality of positions. as a result,
Since the rotation range of the resin mold layer with respect to the metal flange can be suppressed to the range of the gap length generated between the resin mold layer and the metal flange by curing and shrinking, it remains at the injection port of the casting resin. The relative position of the resin mold layer with respect to the metal flange can be held more accurately and stably compared to the conventional method in which the protrusion is used as the rotation stopping means, and the resin mold layer is connected and supported through the embedded conductor. It is possible to provide a gas-insulated switchgear provided with an insulating spacer that can accurately hold the position of the switchgear, particularly the position in the circumferential direction. In addition, the positioning accuracy of the resin mold layer with respect to the metal flange improves the positioning of the storage device including the high-current conductor and the ground switch with the insulating spacer fixed to the ground metal container when the GIS assembly work is performed. It is possible to do so, and there is an advantage that it can contribute to the improvement of the assembly dimension accuracy of GIS and the labor saving and time saving of the assembling work.

[Brief description of drawings]

1A and 1B are a plan view and a side sectional view of an insulating spacer showing an embodiment of the present invention, FIG. 2 is an enlarged sectional view of an essential part of the embodiment, and FIG. 3 is a different embodiment of the present invention. Fig. 4 is a partial crushed sectional view of the main part, Fig. 4 is a side sectional view of the main part showing the general structure of the gas-insulated switchgear, and Figs. 5A and 5B are plan views and A showing a conventional insulating spacer. -A
It is sectional drawing of a direction. 1 ... Insulating spacer, 2, 12 ... Resin mold layer, 3 ...
Embedded conductor, 4,14 …… Metal flange, 4A, 14A …… U-shaped recessed groove, 20,20A, 20B, 20C …… Roll stop, 21 …… Dimple,
22,22A, 22B …… Projection part, 31A, 31B, 31C …… Grounded metal container, 32 …… Charging part (high current conductor), 39A, 39B …… Gas compartment, w …… Width of metal flange, w ₁ Width of groove, g ...
… Gap length.

Claims (1)

[Claims] 1. A resin mold layer including a metal flange having a U-shaped groove along an inner peripheral surface and an embedded conductor, which are integrally resin-molded with an epoxy-based casting resin composition. The outer peripheral portion of the gas-insulated switchgear is airtightly sandwiched between the flanges of the grounded metal containers adjacent to each other to form a gas division chamber, and the charging part of the switchgear connected to the embedded conductor is insulated and supported. At
It is composed of recesses formed at a plurality of positions in the circumferential direction of the U-shaped groove, and protrusions formed on the resin mold layer so as to fill the recesses, and is separated from the metal flange to have a gap. An insulating spacer for a gas-insulated switchgear, characterized in that a rotation preventing portion of a resin mold layer is provided.