JP2000011783A - Resin insulator and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a resin insulator capable of preventing an electrical defect arising due to a parting line. SOLUTION: In this resin insulator 1 with a plurality of shed parts 2b provided on the periphery of an insulator body 2 at fixed intervals in the longitudinal direction of the insulator body 2, parting lines 7 existing on surfaces of the insulator body 2 and of the respective shed parts 2b are provided in a circumferentially shifted manner from each other at every fixed interval in the longitudinal direction of the insulator body 2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin insulator provided with a plurality of umbrella portions and used for manufacturing various insulators, arrestors, bushings, cutouts and the like in the field of power transmission and the like, and a method of manufacturing the same. .

[0002]

2. Description of the Related Art As a resin insulator, an epoxy insulator for indoor use has been known for a long time, and recently, an outdoor insulator using a cycloaliphatic glycidyl ester-based epoxy resin, and a weather resistant material around an FRP rod. Developed an outdoor insulator with an umbrella using a resin with tracking resistance, etc.
It is being commercialized. In this case, resins having weather resistance and tracking resistance include EPDM (ethylene propylene diene monomer), PTFE (polytellorafluoroethylene), silicone rubber, EVA (ethylene vinyl acetate copolymer) and the like.

[0003] These resin insulators can be designed to be more compact than conventional porcelain insulators, and the specific gravity of the material itself is small, so that the weight can be reduced. Therefore, the mounting workability can be improved and the mounting structure can be simplified. Is spreading.

FIG. 9 shows an example of a conventional resin insulator 1 applied to a bushing. This resin insulator 1
An umbrella portion 2b is formed on the outer periphery of the cylindrical insulator main body 2 at a plurality of stages at predetermined intervals in the longitudinal direction of the insulator main body 2. This resin insulator 1 is mounted on the outer circumference of an insulating cylinder 4 made of FRP. A conductor is accommodated in the insulating cylinder 4, and connection terminals 5 a and 5 b for connecting to the conductor are provided outside the insulating cylinder 4.
At the connection terminal 5b side, on the outer periphery of the insulating cylinder 4, a mounting bracket 6 is provided.
Is installed.

[0005]

However, such a resin insulator 1 is resistant to leakage current due to fouling and rainfall.
Compared to porcelain insulators, erosion such as tracking degradation and the formation of carbonized conductive paths are more likely to occur. For this reason, for example, an additive (for example, Mg (OH) ₂ , Al (OH) ₃ ) for improving the tracking resistance is added to the umbrella portion 2 b as described above.
However, since the resin insulator 1 is a molded product using a metal mold, a burr called a parting line 7 which always occurs at the joint of the mold is generated on the surface.

The parting line 7 is usually continuous in the longitudinal direction, and has a problem that it becomes an electric weak point. This is because pollutants such as dust in the atmosphere are continuously adhered to the parting line 7, and rainwater easily accumulates during rainfall or becomes a path of rainwater. However, there is a problem that the leakage current tends to flow in a concentrated manner, leading to deterioration of the dielectric strength and tracking, and lowering the reliability of the electrical insulation.

An object of the present invention is to provide a resin insulator which can prevent the occurrence of electrical defects caused by a parting line, and a method of manufacturing the same.

Another object of the present invention is to provide a resin insulator which can more effectively prevent the occurrence of electrical defects caused by a parting line, and a method of manufacturing the same.

[0009]

According to the present invention, there is provided a resin insulator having a structure in which umbrella portions are provided at a plurality of stages at predetermined intervals in the longitudinal direction of the insulator main body on the outer periphery of the insulator main body and are formed of synthetic resin. Is to improve.

In the resin insulator according to the present invention, the parting lines provided on the surfaces of the insulator main body and each umbrella portion are circumferentially shifted at predetermined intervals in the longitudinal direction of the insulator main body.

If the parting line is shifted in the circumferential direction at predetermined intervals in the longitudinal direction of the insulator main body, the parting line will not be continuous in the longitudinal direction of the resin insulator. For this reason, it is possible to prevent the occurrence of an electrical defect caused by the parting line.

[0012] In this case, the parting line is formed by using each umbrella portion and one trunk portion connected to one side thereof as a unit insulator portion.
It is preferable to dispose in a circumferential direction for each adjacent unit insulator portion. By doing so, the parting line is shifted in the circumferential direction for each unit insulator portion, and the occurrence of electrical defects due to the parting line can be more effectively prevented.

The present invention also includes a plurality of molding pieces positioned with their end faces facing each other, and each of the molding pieces is divided by a dividing plane in the longitudinal direction through the center or the vicinity thereof. In a plurality of molding pieces arranged with their end faces facing each other, a resin having a structure in which umbrella portions are provided in a plurality of stages at predetermined intervals in the longitudinal direction of the insulator main body on the outer periphery of the insulator main body. A molding die hole for molding an insulator is formed in a state of being divided by a plurality of molding pieces, and the method for filling a resin into the molding hole and molding a resin insulator is improved. It is.

In the method for manufacturing a resin insulator according to the present invention, the molding pieces are arranged such that the divided surfaces thereof are shifted in the circumferential direction between adjacent ones and the laminated surfaces are brought into close contact with each other. A resin is filled into a molding die hole continuously formed in each molding piece to form a resin insulator.

As described above, when the molding pieces are arranged such that the divided surfaces thereof are shifted from each other in the circumferential direction between the adjacent pieces, the resin is filled into the molding die holes formed continuously in these molding pieces and the resin is filled. When the insulator is formed, the parting line is generated at a predetermined interval in the longitudinal direction of the insulator main body and shifted in the circumferential direction.

In this case, as each molding piece, a molding die hole for molding each unit insulator portion composed of each umbrella portion of the resin insulator to be molded and one body portion connected to one side thereof is formed therein. It is preferable to use those having the structures provided respectively, and to dispose these molding pieces such that their division surfaces are shifted in the circumferential direction between adjacent ones. This makes it possible to easily form a resin insulator in which the parting line is shifted in the circumferential direction for each unit insulator portion.

[0017]

FIG. 1 is a perspective view showing an example of an embodiment of a resin insulator according to the present invention.

This resin insulator 1 shows an example applied to a bushing as in the conventional example. This resin insulator 1
In the above, the parting lines 7 provided on the surfaces of the insulator main body 2 and each umbrella portion 2b are shifted in the circumferential direction at predetermined intervals in the longitudinal direction of the insulator main body 2. In particular, in the present example, the parting line 7 is configured such that each umbrella portion 2 b and one trunk portion 2 a connected to one side thereof are unit insulator portions 8.
Each adjacent unit insulator portion 8 is shifted in the circumferential direction. In this example, an example is shown in which the parting lines 7 are alternately shifted by 90 ° in the circumferential direction for each adjacent unit insulator portion 8, but the shift angle is not limited to 90 °. The angle is not limited to being shifted alternately, and may be shifted to an appropriate angle in accordance with the mounting situation, use environment, application, and the like. Other configurations are the same as those in FIG. 9 described above, and corresponding portions are denoted by the same reference numerals.

When the parting line 7 is shifted in the circumferential direction at predetermined intervals in the longitudinal direction of the insulator main body 2 as described above, the parting line 7 does not continue in the longitudinal direction of the resin insulator 1. For this reason, it is possible to prevent the occurrence of an electrical defect caused by the parting line 7. In particular, if the parting line 7 is displaced in the circumferential direction for each adjacent unit insulator portion 8 with each umbrella portion 2b and one trunk portion 2a connected to one side thereof as a unit insulator portion 8, a unit insulator The parting line 7 is displaced in the circumferential direction for each part 8, so that it is possible to more effectively prevent the occurrence of electrical defects caused by the parting line 7.

FIGS. 2 to 5 show the construction of a resin insulator manufacturing apparatus used in a first embodiment of the method for manufacturing a resin insulator according to the present invention. FIG. 2 shows a piece holder used in the present embodiment. FIG. 3 is a perspective view showing a process of sandwiching each molding piece in a piece holder in this example, FIG. 4 is a perspective view of the molding piece used in this example, and FIG. 5 is each molding piece used in this example. FIG. 6 is a plan view showing the configuration of the lower half of the resin insulator manufacturing apparatus of the present example.

In the method for manufacturing the resin insulator of this embodiment, the opposing surface 9
a, 9a 'are used in a pair, and a pair of piece holders 9, 9' are combined. Combined piece holder 9, 9 '
Inside, a cylindrical piece positioning housing chamber 10, a cylindrical body positioning housing hole 11, and a mandrel positioning housing hole 12 are provided by being divided into two by opposing surfaces 9 a and 9 a ′. The frame positioning housing chamber 10 is located at the center of the frame holders 9 and 9 ', the cylindrical positioning housing holes 11 are located on both sides in the central axis direction of the frame positioning housing chamber 10, and the mandrel positioning housing holes 12 are provided in the respective cylinders. It is provided as shown in the figure so as to be present at the end of the body positioning accommodation hole 11 in the center axis direction and to be opened at the end faces of the piece holders 9 and 9 '.

A plurality of annular forming pieces 13 are positioned in the piece positioning chamber 10 at predetermined intervals 14 for forming the umbrella portion 2b on adjacent end faces 13a, and the outer peripheral face is positioned. The container is accommodated in a state where it is positioned in the circumferential direction by contacting the inner peripheral surface of the accommodation room 10. Although not shown, the positioning of each molding piece 13 in the longitudinal direction in the piece positioning accommodation chamber 10 is performed by providing concave or convex positioning means on the inner surface of the piece positioning accommodation chamber 10 and the outer peripheral surface of each molding piece 13. ing. In the plurality of molding pieces 13 arranged in this way, a molding die hole 15 for molding the resin insulator 1 as shown in FIG. In particular, in the present example, each unit insulator portion 8 composed of each umbrella portion 2b of the resin insulator 1 to be molded and one body portion 2a connected to one side thereof is formed in each molding piece 13 as shown in FIG. The mold holes 15P are provided as shown in FIG. The mold hole 15P is provided with the insulating cylinder 4 at the center.
And a body forming hole 15pa for forming the body 2a by securing the thickness of the body 2a of the resin insulator 1 on the outer periphery of the insulating cylindrical body 4 and one umbrella portion 2b of the resin insulator 1 adjacent to the body 2a. And an umbrella forming hole 15pb formed between the forming pieces 13 to be formed.
Each of the forming pieces 13 passes through the center of the body forming hole 15pa or in the vicinity thereof, and the dividing surface 13b extends in the longitudinal direction.
Is divided into two.

In this embodiment, each molding piece 13 having such a structure is used.
Are stored in the frame positioning housing chamber 10 with the dividing surface 13b shifted by, for example, 90 ° in the circumferential direction between adjacent ones as shown in FIG. Each of the molding pieces 13 and the upper piece holder 9 'are provided with resin injection holes 16 for injecting resin into the internal mold hole 15P as shown in FIGS. The resin is supplied to these resin injection holes 16 from a resin reservoir 17 formed by recessing the upper surface of the upper piece holder 9 ′.

The body forming hole 15pa of each forming piece 13 is made to penetrate the insulating cylinder 4 made of FRP with a required gap (interval corresponding to the thickness of the body 2a) from the inner periphery thereof. . An iron mandrel 18 is passed through the insulating cylinder 4 with its outer peripheral surface in close contact with the inner peripheral surface of the insulating cylinder 4. Both ends of the insulating cylinder 4 are positioned and accommodated in the cylinder positioning accommodation holes 11 in the piece holders 9, 9 ′.
′ Is positioned and accommodated in the mandrel positioning and accommodating hole 12. The mandrel 18 fits its flanges 18a, 18b into the flange fitting portions 12a, 12b of the mandrel positioning accommodation hole 12, whereby
Position in the axial direction. In this state, the insulating cylinder 4
6, there is a gap between the outer peripheral surface of the insulating cylinder 4 and the inner peripheral surface of the body forming hole 15pa corresponding to the thickness of the body 2a, as shown in FIG. Can be.

After each of the molding pieces 13, the insulating cylinder 4 and the mandrel 18 are set in the lower piece holder 9 as described above, the upper piece holder 9 'is put thereon, and the pressure is applied from above. Then, the resin is supplied from the resin reservoir 17 to the molding die holes 15P in the molding pieces 13, and the resin insulator 1 is molded.

When the resin insulator 1 is molded in this way, each molding piece 13 molded from the resin insulator 1 has its divided surface 13b shifted by 90 ° in the circumferential direction, for example, by 90 °. Therefore, as shown in FIG. The resin insulator 1 in which the line 7 is shifted in the circumferential direction can be easily formed.

In the case of the resin insulator manufacturing apparatus of the first example, each molding piece 13 is fitted and supported in the piece positioning housing chamber 10 of the piece holders 9 and 9 '.
There is an advantage that the position of the dividing surface 13b in the circumferential direction between the adjacent three can be set arbitrarily, and therefore, the parting line 7 can be shifted at an arbitrary angle in the circumferential direction.

FIGS. 7A and 7B show a lower half of a second embodiment of the resin insulator manufacturing apparatus for carrying out the method for manufacturing a resin insulator according to the present invention. Has a similar structure. In these figures, FIG.
FIG. 7B is a plan view showing a state in which the molded pieces are stacked in a continuous state and sandwiched between the piece holders at both ends, and FIG.
It is a right view of the piece holder shown to (A).

In the method of manufacturing a resin insulator according to the present embodiment, a plurality of molding pieces 13 are brought into close contact with each other at their end surfaces 13a, and
Positioning of the molding pieces 13 is carried out, and the piece holders 9 are placed on both ends of the molding pieces 13 in the laminating direction. Each forming piece 13 and the piece holder 9 are connected by connecting bolts (not shown) that pass through a plurality of connecting holes 19 penetrating in the stacking direction.
The connecting holes 19 are provided at predetermined intervals (for example, at intervals of 5 ° to 20 °) on each molding piece 13 and the piece holder 9 on the same circumference having a predetermined radius from the center when viewed from the end in the stacking direction. Keep it.

As described above, a plurality of molding pieces 13 for molding the resin insulator 1 as shown in FIG. It is formed in a state divided by 13. In particular, in the present example, each unit insulator portion 8 composed of each umbrella portion 2b of the resin insulator 1 to be molded and one body portion 2a connected to one side thereof is formed in each molding piece 13 as shown in FIG. Forming holes 15P are provided. The mold hole 15P is
A body forming hole 15pa for penetrating the insulating cylinder 4 at the center and securing the thickness of the body 2a of the resin insulator 1 around the outer periphery of the insulating cylinder 4 to form the body 2a; And a head forming hole 15pb for forming two heads 2b. Each of the forming pieces 13 is divided into two by a dividing surface 13b in the longitudinal direction through the center of the body forming hole 15pa or the vicinity thereof.

In this embodiment, each molding piece 13 having such a structure is used.
Are arranged such that the divided surface 13b is shifted around the center of the molding piece 13 by, for example, 5 ° to 20 ° between adjacent ones. In this way, the adjacent forming pieces 13 are moved around their centers by 5 ° to 20 °.
Even if they are staggered, since the connecting holes 19 are provided at an interval of 5 ° to 20 ° with respect to the center of each forming piece 13, the connecting holes 19 of the adjacent forming pieces 13 match. In this example,
It is not necessary to pass the connecting bolts through all of the plurality of rows of the matched connecting holes 19, and the connecting bolts may be connected through appropriate rows of the matching rows of the connecting holes 19. However, the divided surfaces 13b of the molding pieces 13 do not coincide as shown in FIG. 7 (A), and enter and exit according to the angle to be shifted. Dividing surface 13b of each molding piece 13 on the opposite side (not shown)
When the divided surface 13b of the lower molding piece 13 shown in the drawing protrudes, it is in a retreating state, and when it is retracted, it is in a protruding state, so that the upper mold and the lower mold mesh with each other.

Each of the molding pieces 13 has an internal molding hole 15.
A resin injection hole 15 for injecting resin into P is provided. Resin is supplied to these resin injection holes 15 from a resin supply unit (not shown).

The FRP insulating cylinder 4 is made to penetrate the body forming hole 15pa of each forming piece 13 with a required gap (interval corresponding to the thickness of the body 2a) from the inner periphery thereof. . An iron mandrel 18 is passed through the insulating cylinder 4 with its outer peripheral surface in close contact with the inner peripheral surface of the insulating cylinder 4. Both ends of the insulating cylinder 4 are positioned and accommodated in a cylinder positioning accommodation hole 11 in the piece holder 9, and the mandrel 18 is positioned and accommodated in the mandrel positioning accommodation hole 12 in the piece holder 9. The mandrel 18 is positioned in the axial direction by fitting the flanges 18 a and 18 b into the flange fitting portions 12 a and 12 b in the middle of the mandrel positioning accommodation hole 12. In this state, due to the presence of the mandrel 18 supporting the insulating cylinder 4, the trunk 2a is placed between the outer peripheral surface of the insulating cylinder 4 and the inner peripheral surface of the trunk forming hole 15pa as shown in the figure.
At intervals corresponding to the wall thickness of

In the manufacturing method of this embodiment, it is preferable that the upper and lower ends (pressurized surfaces) of the manufacturing apparatus are cut to make a flat surface, or that an attachment is attached to make the flat surface.

The connecting holes 19 as in the present embodiment are provided at predetermined intervals on the same circumference (for example, at the above-mentioned interval of 5 ° to 20 °).
However, the present invention is not limited to the example in which the molding pieces 13 are shifted at the time of design, and the molding pieces 13 are manufactured according to the respective displacement dimensions. As shown in FIG.
It is also possible to provide a plurality of connection holes 19 corresponding to 3. If a predetermined number of such molding pieces 13 are manufactured in advance and the molding pieces 13 are alternately turned upside down and combined, the connecting holes 19 are arranged at a predetermined interval (for example, 5 ° to It is not necessary to provide them at intervals of 20 °).

Even if the above-described resin insulator manufacturing apparatus is used, the resin insulator 1 in which the parting line 7 is displaced in the circumferential direction for each unit insulator portion as shown in FIG. 1 can be easily formed.

In the above example, an example in which the present invention is applied to a bushing is shown. However, the present invention is not limited to this, and is similarly applied to various insulators, arresters, cutouts and the like in the field of power transmission. You can do it.

[0038]

In the resin insulator according to the present invention, the parting lines provided on the surfaces of the insulator main body and each umbrella portion are circumferentially shifted at predetermined intervals in the longitudinal direction of the insulator main body. Therefore, the parting line is not continuous in the longitudinal direction of the resin insulator, and therefore, it is possible to prevent the occurrence of electrical defects due to the parting line.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of an embodiment of a resin insulator according to the present invention.

FIG. 2 is a perspective view showing a configuration of a piece holder of a resin insulator manufacturing apparatus used in a first example of an embodiment of a method for manufacturing a resin insulator according to the present invention.

FIG. 3 is a perspective view showing a process of sandwiching each molding piece in a piece holder in this example.

FIG. 4 is a perspective view of a molding piece used in this example.

FIG. 5 is a perspective view showing a state in which molding pieces used in the present example are arranged.

FIG. 6 is a plan view showing a configuration of a lower half portion of the resin insulator manufacturing apparatus of the present example.

FIGS. 7A and 7B show a lower half part of a second example of the embodiment of the resin insulator manufacturing apparatus for performing the resin insulator manufacturing method according to the present invention, and FIG. FIG. 4B is a plan view showing a state in which the molded pieces are stacked in a continuous state sandwiched between the piece holders at both ends, and FIG. 4B is a right side view of the piece holder shown in FIG.

FIG. 8 is a front view showing another example of a molding piece used in the resin insulator manufacturing apparatus of the second example.

FIG. 9 is a perspective view showing a conventional resin insulator.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Resin insulator 2 Insulator main body 2a Body part 2b Umbrella part 4 Insulating cylinder 5a, 5b Connection terminal 6 Mounting bracket 7 Parting line 8 Unit insulator part 9, 9 'Piece holder 9a, 9a' Opposing surface 10 Piece positioning accommodation room 11 Cylindrical positioning receiving hole 12 Mandrel positioning receiving hole 13 Molding piece 13a End face 13b Dividing surface 14 Spacing 15 Molding hole 15P Molding hole 15pa Body molding hole 15pb Umbrella molding hole 16 Resin injection hole 17 Resin reservoir 18 Mandrel 18a , 18b Tsuba 19 Connection hole

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Takushi Yoshikura 2-1-1-11 Tagawa, Yodogawa-ku, Osaka-shi F-term in Daihen Corporation (reference) 5G331 AA03 AA07 BB29 BC09 CA04 DA01 DA04 5G333 AA09 AA11 AB01 AB28 BA01 CB15 CC09 DA03 EA02

Claims (4)

[Claims] 1. A resin insulator formed of a synthetic resin having a plurality of umbrella portions provided on a periphery of the insulator main body at predetermined intervals in a longitudinal direction of the insulator main body, wherein the insulator main body and the respective umbrella portions are provided. Wherein the parting line provided on the surface of the resin insulator is circumferentially shifted at predetermined intervals in the longitudinal direction of the insulator main body. 2. A resin insulator formed of a synthetic resin having umbrella portions provided at a plurality of stages at predetermined intervals in a longitudinal direction of the insulator main body on an outer periphery of the insulator main body, wherein the insulator main body and each of the umbrella portions are provided. The parting line provided on the surface of the umbrella section is connected to each umbrella section and one side thereof.
A resin insulator characterized in that the two body portions are adjacent to each other as unit insulator portions and are shifted in the circumferential direction for each adjacent unit insulator portion. 3. A plurality of molding pieces positioned so that end faces between adjacent ones are opposed to each other, wherein each of the molding pieces is divided by a dividing surface in a longitudinal direction through a center or a vicinity thereof. In the plurality of molding pieces arranged with the end faces facing each other, an umbrella portion is provided on the outer periphery of the insulator main body at a plurality of stages at predetermined intervals in the longitudinal direction of the insulator main body. A method of manufacturing a resin insulator, wherein a molding die hole for molding a resin insulator is formed in a state divided by the plurality of molding pieces, and a resin is filled in the molding die hole to mold the resin insulator. In the above, each of the molding pieces is arranged such that the division surface thereof is shifted in the circumferential direction between adjacent ones, and a resin is filled into the molding die holes formed continuously in each of the molding pieces, and the resin is filled. Manufacture of resin insulator characterized by molding insulator Law. 4. A plurality of molding pieces which are positioned in a state where end faces between adjacent ones are opposed to each other, wherein each of the molding pieces is divided by a dividing plane in a longitudinal direction through a center or a vicinity thereof. In the plurality of molding pieces arranged with the end faces facing each other, an umbrella portion is provided on the outer periphery of the insulator main body at a plurality of stages at predetermined intervals in the longitudinal direction of the insulator main body. A method of manufacturing a resin insulator, wherein a molding die hole for molding a resin insulator is formed in a state divided by the plurality of molding pieces, and a resin is filled in the molding die hole to mold the resin insulator. In each of the molding pieces, a molding die hole for molding each of the unit insulator portions each including the umbrella portion of the resin insulator to be molded and one body portion connected to one side thereof is formed therein. Use the one provided The molding pieces are arranged such that the dividing surfaces thereof are shifted from each other in the circumferential direction between adjacent molding pieces, and a resin is filled in the molding die holes continuously formed in the respective molding pieces to form the resin insulator. A method for producing a resin insulator, which comprises molding.