JPH1080026A - Insulating spacer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To ensure the secure contact of a movable contact to a fixed contact at the disconnector of a gas insulated swithgear by holding the outer surface part of a resin composition layer at the dovetail groove of a metal ring by the contraction in the formation of thermosetting resin composition layer between the charging- conductor connecting metal fitting and the metal ring in the metal ring. SOLUTION: For example, a metal ring 1 and a charging-conductor connecting metal fitting 2 are set in a sprit-ring metal mold, which is closed in the direction. The mold is closed and arranged in the longitudinal direction. Air is drawn out by pressure reduction from the resin injecting port on the metal mold through a resin flow-path port 12 of the metal ring 1. Thereafter, filler-adding-liquid shaped liquid is injected, the resin is hardened by the heating of the metal mold, and the mold releasing is performed. In this case, pressure acts on the contraction in the diametrical direction of the thermosetting resin formation 3 in a side surface 111 of the taper (angle of taper surface is 3 deg.-20 deg.) in a dovetail groove 11. The outer surface part of the resin forming layer 3 is held with the taper surface 111 at the inner surface of the dovetail groove 11. Therefore, the movement is restricted by the holding time point for the arbitrary diagonal direction acting on the resin forming layer 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a spacer used for insulating and supporting a charging part conductor in a cylindrical metal container, and is particularly useful for insulating and supporting the charging part conductor in a gas insulated switchgear. It is something.

[0002]

2. Description of the Related Art In a gas insulated switchgear, the components of the switchgear, that is, the charging section of the busbar, circuit breaker, disconnector, lightning arrestor, and other devices are arranged in the center of a cylindrical grounded metal container and charged. Space at predetermined intervals in the length direction.
Supported by support, and pressure filling pressure to the cylindrical ground metal container with excellent gas insulation characteristics such as SF _6. Figure 4 shows an example of a disconnector-grounding switch portion of the phase-separated in the gas insulated switchgear, the conductive rod 42 having a grounding switch fixed contact 41 to the tip insulating space - supported by the support a _1, the tip the conductor rod 52 having a main fixed contact 51 in the insulating space - is supported by support a _2, a main movable contact 53 and the grounding switch movable contact 43
Are provided so as to be able to linearly move from the outside, and the main movable contact 53 is slidably inserted into the conductor rod 42 in a direction perpendicular to the conductor bar 42, and the cylindrical grounded metal container 6 is filled with SF ₆ gas and pressurized. The disconnection is carried out by an external operation of 53, and in this disconnected state, the grounding switch side movable contact 43 is brought into contact with the grounding switch fixed contact 41 by an external operation so that the cable line can be grounded.

FIG. 5A shows an insulation spacer in a gas insulated switchgear, in which a metal part 1 'for connecting a charged part is disposed at the center of a metal ring 1' having a concave groove 11 'along the inner peripheral surface. Then, the thermosetting resin composition 3 ′ is cast into a layer between the metal ring 1 ′ and the metal fitting 2 ′ for connecting the charging section, and a packing mounting groove 31 ′ is provided on each side of the outer periphery of the resin partition 3 ′. For fixing to the grounded metal container, as shown in FIG. 5B, packings 62 are attached between the outer peripheral side surfaces of the resin layer 3 ′ and the metal container end flanges 61, respectively. A structure in which the metal ring 1 'is bolted between the metal container end flanges 61, 61 is used.

[0004] To form the insulating spacer, the metal ring and the charging portion connection metal fitting are set in a cracking mold, and the space between the metal ring and the charging portion connection metal fitting is vented. A so-called casting method is used in which a thermosetting resin liquid is injected while charging the resin liquid, the mold is carried into a heating furnace, the resin is heated and cured, and then taken out of the furnace and removed from the mold. Have been. However, in the casting method, the heat shrinkage of the resin is considerably larger than the heat shrinkage of the metal. Heat shrinks greatly, and this shrinkage also overlaps with hardening shrinkage, and the interface between the metal ring and the hardened resin layer peels off, forcing the generation of a gap.

[0005] Thus, the resin layer is movable in the circumferential direction with respect to the metal ring, so that the positioning in the circumferential direction cannot be restricted, which hinders the assembly of the gas insulated switchgear. In order to eliminate such inconvenience, a recess is provided on the bottom surface of the concave groove of the metal ring, and a protrusion is formed on the outer periphery of the resin layer to be locked in the recess, and the protrusion is locked in the recess with respect to the rotation in the circumferential direction. It has been proposed to perform a function as a detent (Japanese Patent Publication No. 7-99888).

[0006]

However, even in this detent structure, a gap is formed between the metal ring and the resin layer over the entire circumference of the metal ring, and the gap in the circumferential and radial directions within this gap is reduced. Because it is inevitable,
The positioning accuracy with respect to the charged part has a limit due to the displacement based on the gap. Therefore, in FIG. 4, the positions of the fixed contacts 41 and 51 in the grounded metal container 6 are shifted within this limit, and the movable contacts 43 and 53 are eccentrically contacted with the fixed contacts 41 and 51. There is a fear that the contact operation of the movable contact may be hindered. In particular, in the case of the three-phase package type, the center of the insulating spacer does not coincide with the center of each phase connecting part fitting. As a result of displacing the center of the charger connection fitting in the circumferential direction by the distance aΔθ, the deviation of the center of each phase fixed contact from the center of each phase movable contact becomes significantly large, and the phase fixed contact of each phase movable contact There is a fear that contact with the child may not be possible. Furthermore, in the case of the three-phase batch type, each phase charging unit receives an alternating electromagnetic force having a frequency twice the current frequency based on the supplied current, and the resin layer of the spacer vibrates in the gap to cause noise. There is fear.

[0007] An object of the present invention is to provide a live part connecting metal fitting in a metal ring having a concave groove along the inner peripheral surface,
In the insulating spacer in which the thermosetting resin composition layer is cast between the metal fitting and the metal ring, the inner peripheral surface of the metal ring and the resin composition layer are shrunk by the shrinkage of the resin composition layer at the time of casting. Even if there is a gap between them, it is possible to assemble the gas insulated switchgear with high dimensional accuracy by eliminating the backlash, and to ensure that the movable contact to the fixed contact at the disconnector part of the gas insulated switchgear. An object of the present invention is to provide an insulating spacer capable of guaranteeing a contact.

[0008]

According to the present invention, there is provided an insulating space according to the present invention.
The spacer is a spacer used to insulate and support the charging part conductor in the cylindrical metal container, and both side surfaces of the inner surface are provided with dovetail grooves of the taper surface along the inner peripheral surface of the metal ring. A metal part for connecting a charged part conductor is provided in the metal ring, a thermosetting resin composition layer is cast between the metal part and the metal ring, and the resin composition layer shrinks during casting. The outer periphery of the resin composition layer is bitten by the dovetail groove of the metal ring, and the angle of the taper surface in the dovetail groove to the radial line of the metal ring is usually 3 ° to 20 °. °.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. 1A is a side view showing an example of the insulating spacer according to the present invention, FIG. 1B is a cross-sectional view of FIG. 1A, and FIG. It is an enlarged view in the dotted frame in (b) of FIG. In FIG. 1A and FIG. 1B, reference numeral 1 denotes a metal ring, and a dovetail groove 11 is provided along the inner peripheral surface. As shown in FIG. 1C, the angle (the angle α in the figure) between the taper side surface 111 on the inner surface of the dovetail groove 11 and the radial line RR of the metal ring 1 is as described later. , Usually 3 °
２０20 °. Reference numeral 12 denotes a resin flow passage hole formed in the metal ring 1, and reference numerals 13, ... denote bolt insertion holes. Reference numeral 2 denotes a metal fitting for connecting the charging portion conductor, and the center of the metal fitting 2 substantially coincides with the center of the metal ring 1. 3 is a metal ring
A thermosetting resin composition layer cast between the metal ring and the charging part conductor connection fitting 2, and as described later, the metal ring has a dovetail bottom surface and an inner peripheral surface outside the dovetail groove due to shrinkage during casting. Although the interface with the resin composition layer has been peeled off, the outer periphery of the resin composition layer is bitten on the side surface of the tape in the dovetail groove. Reference numeral 31 denotes a packing mounting groove formed near the outer periphery of both side surfaces of the resin composition layer 3.

The insulating spacer shown in FIG. 1 is used when one charging conductor is insulated and supported in each cylindrical metal container for each of the three phases. In the case where the charging section conductors are insulated and supported in a three-phase batch type, as shown in FIG. 2, each phase charging section conductor connection fitting 2 is an equilateral triangle, and the center of the equilateral triangle is substantially at the center of the metal ring 1. Arranged to be coincident.

If the angle α of the tapered surface in the dovetail groove with respect to the radial line of the metal ring 1 is too large, the tensile stress acting on the outer periphery of the thermosetting resin layer due to shrinkage during casting becomes excessive, as will be described later. Since the occurrence of resin cracks is a concern, the angle α of the tapered face in the dovetail groove is usually set to 3 ° to 20 °. The metal ring 1 can be made of copper, aluminum, steel, an alloy of each metal, or the like, and the charging part conductor connection fitting 2 can be made of copper, aluminum, or the like. An epoxy resin can be used in the thermosetting resin composition, and a filler such as an alumina powder, a silica powder, and a calcium carbonate powder is usually added.

The above-mentioned insulating spacer is usually manufactured by a casting method. For example, in FIG. 1 (b), a metal ring and a metal fitting are set in a two-piece mold that is closed from the direction, and the mold is closed and arranged vertically, and a resin injection port on the top of the mold is set. From the above, through a resin flow passage hole of the metal ring, air is evacuated by pressure reduction, and then a filler-added liquid resin is injected, and the resin is cured by heating the mold.
It is manufactured by demolding. In this case, the heat shrinkage of the resin is considerably larger than the heat shrinkage of the metal, so that upon cooling, the resin shrinks considerably more than the metal ring, and the hardening shrinkage overlaps with this large shrinkage. As shown in FIG. 3, the dovetail bottom 112 of the metal ring 1 and the cured resin layer 3
And the interface between the outer peripheral surface 113 of the dovetail groove of the metal ring 1 and the cured resin layer 3 are peeled off, and a gap g is generated.

However, the taper side surface 1 in the dovetail groove 11
At 11, pressure acts on the resin layer 3 in radial contraction, and the outer peripheral portion of the resin layer is bitten by the tapered surface 111 on the inner surface of the dovetail groove. Is restricted by the gripping point p, and the opposite radial force −x is restricted by the gripping point p ′.
Further, when the circumferential force acting on the resin layer 3 is applied,
A high frictional force is ensured by the pressure acting on the taper side surface 111 in the inside 1, and circumferential movement is well restrained. In the above description, the resin flow passage hole of the metal ring 1 [(a) of FIG.
In step 12), inject the resin by packing the resin.
If the curing is performed, it can be expected that the stuffed cured resin also shares a part of the above-described circumferential fixing action.

In the above, since the radial shrinkage of the thermosetting resin layer is restricted only by the biting of the inner surface of the dovetail groove of the metal ring by the taper side, the total radial shrinking force of the thermosetting resin layer is limited by the biting. Acts on interfaces. Thus, the tape on the inner surface of the dovetail
It is effective to reduce the par angle α to reduce the concentration of tensile stress at the corner of the dovetail entrance. However, if the taper angle on the inner surface of the dovetail groove is made too small, the above-mentioned pressure becomes small, and it is impossible to expect the contraction of the thermosetting resin layer in the radial direction. Therefore, the taper angle of the inner surface of the dovetail groove is 3 ° to 20 °.
Is appropriate.

In order to prevent a strong electric stress such as causing an electric discharge from acting on the gap, a conductive paint having excellent releasability for metal and easy adhesion to resin, for example, Alternatively, a silicone resin solution containing a metal powder is applied to the inner peripheral surface of the metal ring, and a conductive resin film can be formed on the resin layer surface separated from the inner peripheral surface of the metal ring.

The insulating spacer according to the present invention is used for a case in which the components of a gas insulated switchgear, that is, the charging portion of a device such as a bus, a circuit breaker, and a disconnector is insulated and supported at the center of a cylindrical grounded metal container. Used for It can also be used to insulate and support the inner conductor in the cylindrical outer conductor in a pipeline air transmission line. In this case, except for the spacer for stopping the gas, the resin layer is used to flow gas. Openings can be provided.

[0017]

In the insulating spacer according to the present invention,
Despite the occurrence of a gap at the interface between the metal ring and the thermosetting resin layer, the thermosetting resin layer is stably held without rattling between the dovetail grooves on the inner circumference of the metal ring. In addition, the metal part for connecting the conductor of the charged part at the center of the thermosetting resin layer can be positioned with high precision,
The contact of the movable contact to the fixed contact of the grounding switch can be smoothly performed. Further, since the thermosetting resin layer can be held without play, generation of noise due to the alternating electromagnetic force acting on the metal fitting for connecting the charged portion conductor can be eliminated.

[Brief description of the drawings]

FIG.

FIG. 1A is a side view showing an example of an insulating spacer according to the present invention, FIG. 1B is a cross-sectional view taken along a line in FIG. 1A, and FIG. (C) is an enlarged view in a dotted frame in (b) of FIG.

FIG. 2 is a side view showing another example of the insulating spacer according to the present invention.

FIG. 3 is an explanatory view showing a state in which a dovetail groove of a metal ring is held by a thermosetting resin layer in an insulating spacer according to the present invention.

FIG. 4 is an explanatory diagram showing an example of a disconnector / grounding switch unit in the gas insulated switchgear.

FIG. 5 is an explanatory view showing a conventional insulating spacer.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Metal ring 11 Dovetail 2 Charger conductor connection fitting 3 Thermosetting resin composition layer

[Procedure amendment]

[Submission date] October 18, 1996

[Procedure amendment 1]

[Document name to be amended] Statement

[Correction target item name] Brief description of drawings

[Correction method] Change

[Correction contents]

[Brief description of the drawings]

FIG. 1A is a side view showing an example of an insulating spacer according to the present invention, FIG. 1B is a cross-sectional view of the roll in FIG. 1A, and FIG. It is an enlarged view in the dotted frame in (b) of FIG.

FIG. 2 is a side view showing another example of the insulating spacer according to the present invention.

FIG. 3 is an explanatory view showing a state in which the dovetail groove of the metal ring in the insulating spacer according to the present invention is engaged with the thermosetting resin layer.

FIG. 4 is an explanatory diagram showing an example of a disconnector / grounding switch unit in the gas insulated switchgear.

FIG. 5 is an explanatory view showing a conventional insulating spacer.

[Description of Signs] 1 Metal ring 11 Dovetail 2 Charging part conductor connection fitting 3 Thermosetting resin composition layer

Claims (2)

[Claims] 1. A spacer used to insulate and support a charged part conductor in a cylindrical metal container, and a dovetail groove formed on both sides of the inner surface along a tapered surface along an inner peripheral surface of the metal ring. Provided
A metal part for connecting the live part conductor is arranged in the metal ring,
A thermosetting resin composition layer is cast between the metal fitting and the metal ring, and the outer periphery of the resin composition layer is bitten by a dovetail groove of the metal ring due to shrinkage of the resin composition layer during casting. An insulating spacer characterized by the above. 2. The insulating spacer according to claim 1, wherein an angle of the tapered surface in the dovetail groove with respect to a radial line of the metal ring is 3 ° to 20 °.