JPH0628902Y2 - Insulation spacer - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an insulating spacer used for supporting a conductor and dividing a gas in a gas-insulated electric device such as a gas-insulated switchgear.

[Prior Art] In a gas-insulated electric device such as a gas-insulated switchgear, when a plurality of containers that house the components of the device are connected to each other, an insulating spacer is provided between the containers, The spacers provide gas distribution between the containers and support for the conductors that connect the components of the device. When the conductor is led out through an opening provided in the container of the gas-insulated electrical equipment, an insulating spacer is attached so as to close the opening, and the insulating spacer serves to support the conductor and separate gas inside and outside the container. Planned.

FIG. 4 shows a main part of a conventionally used insulating spacer 1 together with containers 2 and 3 arranged on both sides thereof. The insulating spacer 1 includes a spacer body 100 made of an insulating material such as epoxy resin. The through conductor 102 provided by penetrating the conical conductor supporting portion 101 provided in the spacer body 100, the embedded metal fitting 104 provided on the peripheral flange portion 103 of the spacer main body 100, and the embedded metal fitting 104. The stud bolt 106 is screwed into the through-screw hole 105 provided in the flange portion 103, and the O-ring fitting grooves 107 and 107 are provided in the flange surfaces 103a and 103a at both ends of the flange portion 103. The conductor support portions 101 are provided by the required number of phases, and the through conductors 102 are cast into the conductor support portions 101.

On the flange surfaces 103a, 103a at both ends of the flange portion 103 of the insulating spacer 1, the flanges 201 and 3 of the containers 2 and 3 accommodating the components of the gas-insulated electric equipment, respectively.
01 is abutted, and the stud bolt 106 screwed into the through screw hole 105 of the embedded metal fitting 104 of the insulating spacer is screwed into the fool holes 202 and 302 provided in the flanges 201 and 301, respectively. Then, nuts 4 and 5 are screwed into both ends of the stud bolt protruding from the flanges 201 and 301 of the containers 2 and 3, and the flanges 201 and 3 of the containers 2 and 3 are tightened by tightening these nuts.
01 is fastened via the flange portion 103. The O-ring 6 is fitted in the O-ring screw groove 107, and the O-ring keeps the airtightness of the joint between the flanges 201 and 301 of the container and the flange portion 103 of the insulating spacer. The through conductor 102 supported by each conductor supporting portion 101 has a container 2
The conductors connected to the devices respectively arranged in and 3 are connected by bolts or the like.

[Problems to be Solved by the Invention] In the conventional insulating spacer 1, the embedded metal fitting 104 is provided so as to extend over the entire flange portion 103 of the spacer body 100 in the thickness direction, and the through screw hole 105 is It was provided over the entire length of the embedded metal fitting 104. Therefore, the flange portion 103 is attached to the flange portions 201 and 30 of the container.
In the state in which 1 is fastened, the resin in the vicinity of both end flange surfaces 103a, 103a of the flange portion 103 cannot be freely expanded and stored while being strongly restrained by the embedded metal fitting 104 and the stud bolt 106, so that the temperature of the insulating spacer rises or When it descended, there was a risk that a stress concentration portion would occur in the flange portion 103 and a crack would occur in this portion. That is, when the temperature rises, FIG.
As shown in FIG. 10, the flange portion 103 of the spacer body expands more than the embedded metal fitting 104.
Since the resin in the peripheral portion of No. 4 is constrained by the embedded metal fitting 104, it cannot be freely expanded and the flange portion 1
The surface pressure P acts intensively on the outer peripheral side A part of 03
Concentration of surface pressure occurs on the part. Further, when the temperature of the insulating spacer is lowered, as shown in FIG.
Since the contraction on the flange portion 103 side of the pacer body is larger than the contraction of 04, the contact surfaces of the flange portion 103 and the container flanges 201 and 301 are concentrated in the peripheral portion B of the embedding metal fitting 104. Excessive surface pressure P concentrates and stress concentrates. Particularly in this state, the flange portion 1
03 is constrained by the flanges 201 and 301 of the container only at the B portion and a contracting force acts in the central direction, so that the stress concentration at the B portion becomes extremely large.

As described above, in the conventional insulating spacer, there is a problem in that stress concentration occurs in the B portion near both ends of the embedded metal fitting due to temperature change, and the vicinity of the B portion becomes a weak point of strength of the insulating spacer.

It is an object of the present invention to provide an insulating spacer that has improved strength by eliminating a portion where large stress is concentrated.

[Means for Solving the Problems] According to the present invention, an embedded metal fitting having a through screw hole is provided in a flange portion of a spacer body made of an insulating material, and a stud bolt screwed into the through screw hole of the embedded metal fitting is used. This is an improved insulation spacer for connecting and fixing the flange portion to the flange of the container. In the present invention, the length of the embedded metal fitting is equal to or greater than the inner diameter of the through screw hole and 10 mm from the thickness of the flange.
The embedding metal fitting is set shorter than that described above, and the embedding metal fitting is provided with both ends thereof located at least 5 mm inside the flange surfaces of both ends of the flange portion. Further, in the present invention, recesses which are open to the flange surface side are formed between both ends of the embedded metal fitting and the flange surfaces at both ends of the flange portion, and the inner diameter of the recess is set to be equal to or larger than the outer diameter of the embedded metal fitting.

[Operation] With the above configuration, since both end surfaces of the embedded metal fitting are located away from the flange surface of the flange portion, the resin between the both ends of the embedded metal fitting and the flange surface is free. Then, the resin in this portion plays a cushioning role and prevents the surface pressure and the stress from concentrating on a specific portion.

In addition, as described above, when recesses that open on the flange surface side are formed between both ends of the embedded metal fitting and the flange surfaces on both ends of the flange portion, and the inner diameter of the recess is set to be equal to or larger than the outer diameter of the embedded metal fitting, It is possible to prevent concentration of stress on the resin near both ends of the metal fitting.

Therefore, it is possible to eliminate the possibility that surface pressure is concentrated on the outer peripheral side of the flange part or stress is concentrated on the resin near both ends of the embedded metal fitting, and cracks occur in the flange part. It is possible to improve the sex.

Also, if the length of the embedding metal fitting is set to be equal to or greater than the inner diameter of the through screw hole as described above, the force acting on the embedding metal fitting through the stud bolt when the container flange is connected to both sides of the flange part by the stud bolt. Can withstand.

The distance that must be ensured between both ends of the embedded fitting and the flange surface is at least 5 mm in order to prevent concentration of stress that would cause cracks in a specific portion of the resin that constitutes the flange portion. This has been confirmed by experiments.

[Embodiment] An embodiment of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 shows an embodiment of the present invention. In FIG. 1, parts that are the same as the parts of the conventional example shown in FIG. Reference numerals 3 and 3 respectively denote containers of gas-insulated electrical equipment connected in a gas-divided state via the insulating spacer 1. Insulation spacer 1
Is a spacer body 100 made of resin and a spacer body 1
No. 00, the through conductor 102 cast and supported by the conductor support portion 101, the embedded metal fitting 104 provided on the flange portion 103 of the spacer body 100, and the through screw hole 105 over the entire length of the embedded metal fitting. Threaded stud bolt 10
6 and. The flanges 201 and 301 of the containers 2 and 3 are the flange surfaces 103 at both ends of the flange portion 103.
a, 103a, and the flanges 201 and 3 of the container
The stud bolt 106 is inserted into the holes 202 and 302 provided in the No. 01. Nuts 4 and 5 are screwed into both ends of the stud bolt 106, and the flanges 201 and 301 of the containers 2 and 3 are connected and fixed to the flange portion 103 by tightening these nuts. Flange 103
The O-ring 6 is fitted into the O-ring fitting groove 107 provided in the container, and the O-ring serves to keep the connecting portion between the flange of the container and the flange of the spacer body airtight.

As described above, the insulating spacer of the present invention is basically composed of the same constituent elements as the conventional insulating spacer, but in the present invention, the length 1 of the embedded metal fitting 104 is D ≦ l ≦ ( L-
10) It is set to [Unit: mm]. Here, D is the inner diameter of the through screw hole 106 provided in the embedded metal fitting 104, and L is the thickness of the flange portion 103. Here, the length l of the embedded metal fitting 104 is set to be equal to or larger than the inner diameter D of the through screw hole 105 when the flanges 201 and 301 of the container are connected to both sides of the flange portion 103.
This is to withstand the force acting on the embedded metal fitting 104 through the screw portions of the screw holes 6 and the screw holes 105. Also embedded metal fittings 10
The length l of 4 is set to (L-10) [mm] or less,
This is because both ends of the embedded metal fitting 104 are located at least 5 mm inside the flange surface 103a of the flange portion 103.
That is, in the present invention, the distance l'between both ends of the embedded metal fitting 104 and the flange surface of the flange portion 103 is set to 5 mm or more, and the both ends of the embedded metal fitting 104 and the flange surfaces 103a of both ends of the flange portion 103, The concave recesses 108, 108 that open to both flange surfaces are formed between the recesses 103 and 103a.
The inner diameter D1 of each recess 108 is set to be substantially equal to the outer diameter of the embedding metal fitting 104, or, as shown, the embedding metal fitting 10
It is preferable to set the diameter slightly larger than the outer diameter of No. 4. The cross-sectional shape of the recess 108 may be circular or elliptical.

In the insulating spacer 1 of the above-described embodiment, the outer peripheral A portion of the both end flange surfaces 103a, 103a of the flange portion which is constrained by receiving the surface pressure of the flanges 201 and 301 of the container,
Since the distance between the embedding metal fitting 104 and the peripheral portion B is long, the portion between the portions A and B can freely expand and contract. Therefore, when the flange portion of the insulating spacer expands due to the temperature rise and when the flange portion contracts due to the temperature decrease, the portion between the A portion and the B portion plays the role of a cushion and the A portion has a surface pressure. Prevent people from concentrating. In order to suppress the concentration of the surface pressure at the A portion and the stress concentration at the B portion to the extent that the risk of cracks is eliminated, the distance l'between both ends of the embedded metal fitting 104 and the flange surface 103a. It has been confirmed by experiments that the distance should be 5 mm or more.

As described with reference to FIGS. 5 (a) and 5 (b), in the conventional insulating spacer, the contact state between the flange surface 103a and the container flange changes due to the temperature change, and the surface pressure distribution of the flange surface 103a changes with temperature. Therefore, the surface pressure is concentrated on a specific portion, and the strength tends to be unstable. On the other hand, according to the present invention, the surface pressure distribution of the flange surface 103a hardly changes with temperature, and the surface pressure hardly concentrates, so that an insulating spacer with stable strength can be obtained.

The inventor of the present invention, as shown in FIG.
Keep the length of 4 the same as the thickness of the flange 103,
The length 1 of the screw hole 105 provided in the embedded metal fitting 104 is D ≦ l
By setting ≦ L / 2, the both ends of the screw hole 105 are embedded with the metal fitting 10.
Insulating spacers positioned inside both ends of No. 4 were proposed. In this insulating spacer, the length of the screw hole 105 is shortened to connect the embedded metal fitting 104 to the stud bolt 106 only partially, so that the flange portion of the spacer body acts from the stud bolt and embedded metal fitting side. The restraining force exerted is reduced, the concentration of the surface pressure on the outer peripheral side portion A of the flange portion is suppressed, and the concentration of stress on the portions B near both ends of the embedded metal fitting is suppressed. Therefore, the crack resistance can be improved as compared with the conventional insulating spacer shown in FIG. However, in the previously proposed insulating spacer, since the embedding metal fitting 104 is provided over the entire length of the flange portion 103 in the thickness direction, the embedding metal fitting 10
It is unavoidable that the resin is restrained to some extent near both ends of No. 4 and stress concentration occurs near both ends of the embedded metal fitting 104. According to the present invention, such stress concentration can be avoided, and the crack resistance performance can be further improved.

Further, as shown in FIG. 2, a recess 10 formed between both ends of the embedded metal fitting 104 and the flange surfaces 103a, 103.
It is also conceivable to set the inner diameters of 8 and 108 smaller than the outer diameter of the embedded metal fitting 104. However, in such a configuration, stress is likely to be concentrated on the resin in the vicinity C of both ends of the embedded metal fitting 104, so that the shape of the embedded metal fitting should be taken into consideration by rounding the both end corners of the embedded metal fitting. This is necessary and limits the shape of the implant that can be used. Even if the shape of the embedded metal fitting is taken into consideration, it is unavoidable that a certain amount of stress concentration occurs near both ends of the embedded metal fitting. Therefore, as shown in Fig. 1, when the inner diameter of the recess is set to be larger than the outer diameter of the embedded metal fitting. The crack resistance performance is lower than that of.

[Effects of the Invention] As described above, according to the present invention, both ends of the embedded metal fitting are located at least 5 mm inward from the flange surfaces at both ends of the flange portion, and a recess is formed between both ends of the embedded metal fitting and the flange surface. Since the inner diameter of the recess is set to be larger than the outer diameter of the embedding metal fitting, the resin portion interposed between both ends of the embedding metal fitting and the flange surface can be freely expanded and contracted, and the resin portion can be sufficiently expanded. In addition to providing a good cushioning effect, it prevents cracking resistance by preventing concentration of surface pressure on the outer peripheral side of the flange surface and excessive stress concentration near both ends of the mounting bracket. Can be improved and reliability can be improved.

Since the length of the embedded metal fitting is set to be equal to or larger than the inner diameter of the through threaded hole, the stud bolt screwed into the through threaded hole of the embedded metal fitting is used to fasten the container flange to either side of the flange portion. Also, the embedded metal fitting can sufficiently withstand the tightening force.

Further, since the embedded metal fitting may be shorter than the conventional one, it is possible to reduce the weight and the cost.

[Brief description of drawings]

FIG. 1 is a sectional view showing an essential part of an embodiment of the present invention, FIG. 2 is a sectional view showing an essential part of a reference example to be compared with an insulating spacer according to the present invention, and FIG. 3 is an already proposed insulation. FIG. 4 is a cross-sectional view showing a main part of a spacer, FIG. 4 is a cross-sectional view showing a main part of a conventional insulating spacer, and FIGS. 5 (a) and 5 (b) are respectively a high temperature and a low temperature of the conventional insulating spacer. It is explanatory drawing explaining a state. 1 ... Insulating spacer, 100 ... Spacer body, 101
...... Conductor supporting part, 102 ...... through conductor, 103 ...... flange part, 103a ...... flange surface, 104 ...... embedding metal fitting, 105 ...... through screw hole, 106 ...... stud bolt, 107 ...... O ring fitting Ditch, 108 ... hollow,
2,3 ... Container, 201, 301 ... Container flange.

Claims (1)

[Scope of utility model registration request] 1. A spacer main body made of an insulating material is provided with an embedded metal fitting having a through screw hole in the flange portion, and the flange portion is a flange of a container by a stud bolt screwed into the through screw hole of the embedded metal fitting. In the insulating spacer connected and fixed to, the length of the embedding metal fitting is set to be equal to or more than the inner diameter of the through screw hole and 10 mm or more shorter than the thickness of the flange portion, and the embedding metal fitting has both ends of the embedding metal fitting of the flange portion. It is provided in a state of being located at least 5 mm inward from the flange surfaces on both ends, and recesses that open on the flange surface side are formed between both ends of the embedded metal fitting and the flange surfaces on both ends of the flange portion. An insulating spacer whose inner diameter is set to be larger than the outer diameter of the embedded metal fitting.