JP2807157B2 - High pressure air switch - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a high-pressure air switch which is excellent in insulation and can be reduced in size and weight.

[0002]

2. Description of the Related Art As shown in FIG. 4, a conventional high-pressure air switch has a fixed contact 7 supported and fixed together with an arc-extinguishing tube 17 in a metal outer box 1 and a movable contact 9 connected to the metal contact. The coaxially supported insulating shaft 10 is rotatably supported. Similarly, a lightning proof element 13 and a voltage detection element (PT) 1
4 is stored and fixed. A bushing 4 is provided so as to penetrate the outer case 1, and a current detection element (CT) 15 is fitted to an outer peripheral portion of the bushing 4 in the outer case 1. The high-pressure air switch constructed as described above incorporates a plate-shaped insulating barrier 12 as shown in FIG. 5 in order to reinforce insulation between the internal charging part and the outer case 1 which is a ground potential. ing.

[0003]

However, the high-pressure air switch having such a structure is manually operated using a special tool for assembling each component into the inside of the outer box 1. It is difficult to mechanize parts assembly. In addition, the fitting accuracy of the fixed contact 7 and the movable contact 9 constituting the opening / closing portion depends on the accuracy of the can making of the outer box 1, so that the fitting of the opening / closing portion needs to be adjusted.

As described above, in the conventional high-pressure air switch, it is necessary to secure a working space inside the outer box 1 because the parts are manually assembled, and the outer box 1 is downsized. However, there is a problem that the manufacturing cost is high while the manufacturing is impossible. In addition, since the insulating barrier 12 also has a structure in which the plate-shaped divided members are combined, the charging section and the outer box 1 cannot be completely separated from each other. When the outer box 1 is miniaturized, a lightning impulse test is performed. Then, the occurrence of flashover was confirmed, and there was a problem that insulation was insufficient.

[0005] In particular, in the installation work of an overhead distribution line switch using a high-pressure air switch, an uninterruptible construction method is required. There has been a demand for smaller and lighter air switches.
As a countermeasure, gas switches with better insulation can be substituted.However, gas switches are better than air switches in terms of sealing the outer box, detecting gas leaks, and adding a locking device. Because it becomes expensive. In addition, there are drawbacks such as the inability to incorporate a lightning proof element. SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a high-pressure air switch capable of improving the insulation performance and mechanizing and miniaturizing parts assembly. It is in.

[0006]

SUMMARY OF THE INVENTION To achieve the above object, the present invention provides a method for supporting and fixing each fixed contact in an outer box having a bushing for each phase penetrating the opposing side face. In a high-pressure air switch in which an insulating shaft fitted with the movable contact is rotatably supported from the outside and is supported on an outer box, the insulating shaft is formed into a box shape having four side surfaces and a bottom surface by an insulating material. In addition, the inner side is used as a support fixing part of the fixed contact, and an insulating frame built inside the outer box, a bearing hole formed in the insulating frame to support the insulating shaft, and a phase-by-phase built inside the insulating frame. A partition formed integrally with the insulating frame to insulate the opening and closing portions of the fixed contact and the movable contact from each other, and a partition formed integrally with the insulating frame outside the insulating frame at a position facing the bushing of the outer box. Formed by two cylindrical portions having a cylindrical shape and fitted to the cylindrical bushing end with a gap between the inside and the outside with a gap, and a conductive thin plate attached to the surface of the insulating frame between the adjacent fitting portions. And a ground electrode whose lower end is connected to the outer case.

[0007]

According to the present invention, a box-shaped insulating frame having four side faces and a bottom face made of an insulating material is incorporated inside an outer box, and fixed contacts are supported inside the outer box.
Fixed. The insulating shaft is supported by a bearing hole formed in the insulating frame. The opening / closing portions of the fixed contact and the movable contact incorporated inside the insulating frame are isolated from the opening / closing portions of the other phases, respectively, by the partition walls formed integrally with the insulating frame.

A cylindrical bushing end is inserted into a fitting portion formed by two coaxial cylindrical portions integral with the insulating frame on the outer side of the insulating frame at a position facing the bushing of the outer box. When they are fitted together, the flashing paths formed in the gaps of the fitting portions reciprocate and overlap, and the insulation distance becomes longer by that amount. If a grounding electrode is formed by attaching a conductive thin plate between the surface between the mating parts adjacent to the insulating frame and the outer box, if the insulating frame that insulates the phases is damaged or deteriorated, The ground fault is preceded, and the transition to the interphase short circuit can be avoided.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention, and FIG. 2 is an exploded perspective view of FIG. 1 excluding an outer box. In the figure, reference numeral 21 denotes a metal outer box, and a box-shaped insulating frame 2 having an upper surface opened inside the outer box 21 is incorporated. The insulating frame 2 is manufactured by integral molding using a material having a small linear expansion coefficient and a small molding contraction rate.
In this embodiment, the material is an unsaturated polyester-based GFRP.
Injection molding (BMC) was used. Outer box 21
And the insulating frame 2 are connected and fixed at the bottom by bolts (not shown).

The inside of the insulating frame 2 is divided into three rooms in the longitudinal direction by a partition wall 3, and an opening / closing member for each phase is attached to each room. That is, substantially cylindrical storage spaces are respectively formed at the joint positions between both ends of each partition 3 and the insulating frame 2, and the lightning proof elements 13 are attached. Further, the voltage detecting elements 14 are attached to the inside of the longitudinal end side surface of the insulating frame 2 and to the upper portions at both ends in the width direction. In each of the rooms defined by the partition walls 3, mounting holes 8 are formed on both inner wall surfaces in the width direction, and the fixed contact mounting seats 16 are fixed thereto. This mounting seat 16
Thus, the fixed contacts 7 are supported and fixed, respectively.

A partition wall 3 extends in the longitudinal direction of the insulating frame 2.
And the insulating shaft 10 is mounted on the shaft, and both ends of the insulating shaft 10 are supported by bearing holes 11 formed on both side walls of the insulating frame 2. The movable contact 9 for each phase is fitted to the insulating shaft 10, and when the insulating shaft 10 is rotated, the opening and closing operation with the fixed contact 7 attached to each room is performed. In this case, since the fitting accuracy of the movable contact 9 and the fixed contact 7 depends on the processing accuracy of the insulating frame 2, the fitting accuracy is remarkably improved as compared with an outer box made of a conventional can, and adjustment of fitting is unnecessary. become.

At the position of the mounting hole 8 on the outer surface in the width direction of the insulating frame 2, a fitting portion 5 formed of a double cylinder is protruded outwardly, and the bushing 4 is fitted. FIG.
FIG. 3 is an enlarged cross-sectional view showing a fitting portion 5 and a bushing 4 protruding from an insulating frame 2. As shown in the figure, the cylindrical portion 4a formed at the end of the bushing 4 is inserted into a space between the outer cylindrical portion 5a and the inner cylindrical portion 5b of the fitting portion 5, and is inserted through a slight gap. Supported. as a result,
As shown by the arrow L in the figure, the insulation distance between the conductor 19 of the bushing four-core portion and the outer box 21 that is the ground potential is increased by the amount of bypassing the cylindrical portion 4a.

At the center of the fitting portion 5, a mounting seat 16 supported by the insulating frame 2 is located.
Is fitted with the conductor 19 located at the core portion of the wire. The bushing 4 is in contact with the edge of the hole 22 formed in the outer box 21 via the packing 18 having an L-shaped cross section inside the flange portion 4b formed on the outer periphery thereof. The hole 22 is formed sufficiently larger than the outer diameter of the cylindrical portion 4a of the bushing 4,
As a result, the accuracy of the can 21 of the outer box 21 is reduced. Further, a current detecting element 15 is fitted to the outside of the cylindrical portion 5a outside the fitting portion 5.

In FIG. 1 and FIG. 2, a narrow copper foil is vertically stuck on the outer side in the width direction of the insulating frame 2 and at an intermediate position of the adjacent fitting portion 5 so that the grounding electrode 6 is formed. Is formed. The lower end of the ground electrode 6 is continuous with the lower surface of the insulating frame 2 and is formed up to a bolt hole (not shown) for connecting to the outer case 21 by bolts. Thereby, the lower end of the ground electrode 6 is electrically connected to the outer case 21 and has a ground potential. The ground electrode 6 can be made of other materials as long as it is conductive other than the copper foil. In the high-pressure air switch of this embodiment, since the insulating frame 2 is incorporated in the outer case 21, the insulation distance between the outer case 21 and the internal charging unit and the insulation distance between phases are ensured, and the insulation is improved. .

In the event that the insulating frame 2 itself, which is an insulator, is damaged or deteriorated, a fitting portion 5 made of a double cylinder is formed in the fitting portion of the bushing 4 and a ground electrode 6 is provided. As a result, safety is maintained in advance of a ground fault before the phases are short-circuited. Further, the insulating frame 2 in which the components of the high-pressure air switch are incorporated is finished with higher precision than the outer box 21 and, once the components are attached to the insulating frame 2, the insulating frame 2 is removed from the outer box. Since this is a work process to be incorporated into the assembly 21, the assembly can be mechanized. In addition, an extra space for the assembling work, which is required in the case of manual work, is not required, and the space can be saved. Accordingly, the high-pressure air switch can be miniaturized in combination with the improvement of the insulating property.

[0016]

As described above, according to the present invention, by incorporating the insulating frame inside the outer case, the insulation between the charged portion and the outer case and between the phases is improved, and the size can be reduced. . In addition, since the contacts and other components are attached to the insulating frame, the assembly can be mechanized, and the assembly accuracy is improved, and high-quality high-pressure air with excellent safety, reliability, and productivity is provided. A middle switch can be obtained.

[Brief description of the drawings]

FIG. 1 is a partially cutaway perspective view of an embodiment of the present invention.

FIG. 2 is an exploded perspective view showing the outer box of FIG. 1 without the outer box.

FIG. 3 is an enlarged sectional view showing a main part of FIG. 1;

FIG. 4 is a sectional view showing a conventional example.

FIG. 5 is a perspective view illustrating an internal configuration of a conventional example.

[Explanation of symbols]

 2 Insulating frame 3 Partition wall 4 Bushing 4a Cylindrical part 4b Flange part 5 Fitting part 5a, 5b Cylindrical part 6 Grounding pole 7 Fixed contact 8 Mounting hole 9 Movable contact 10 Insulating shaft 11 Bearing hole 13 Lightning proof element 14 Voltage detecting element 15 Current detection element 16 Fixed contact mounting seat 18 Packing 19 Conductor 21 Outer box 22 Hole

Claims (1)

(57) [Claims] 1. A fixed contact is supported and fixed inside an outer box having a bushing for each phase penetrated on opposing side surfaces, and an insulating shaft fitted with a movable contact for each phase is externally rotated. A high-pressure air switch that is pivotally supported on an outer box by being freely formed into a box shape having four sides and a bottom portion with an insulating material, and the inside as a support fixing portion of a fixed contact,
The insulation frame built inside the outer box, the bearing holes formed in the insulation frame to support the insulation shaft, and the open / close parts of the fixed and movable contacts for each phase built inside the insulation frame A partition formed integrally with the insulating frame to insulate each other, and a cylindrical bushing formed by two coaxial cylindrical portions integral with the insulating frame outside the insulating frame at a position facing the bushing of the outer box. A fitting portion fitted with a gap between the end and the inside and outside, and a ground electrode formed by attaching a conductive thin plate to the surface of an insulating frame between the fitting portions adjacent to each other and having a lower end connected to the outer case; A high pressure air switch characterized by comprising: