JPS6326912Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention is a current limiting element that has a built-in current limiting element unit that discharges abnormal voltages such as incoming lightning surges to the ground in a bag-shaped storage part formed integrally with the main insulator. The present invention relates to an improvement of a built-in box type high voltage cutout, and particularly to a structure that allows a current limiting element unit to be easily and securely attached.

In recent years, in high-voltage distribution lines in lightning-damaged areas, lightning surges that propagate through the distribution lines and try to infiltrate pole transformers are diverted to the ground by current-limiting elements (surge arresters) built into the insulators of the cut-out bodies, thereby preventing abnormalities. A high-voltage cutout with a built-in current limiting element that protects the pole transformer from voltage is used by being connected to the primary side of the transformer.

By the way, in the above-mentioned high-voltage cutout with a built-in current-limiting element, the current-limiting element, both upper and lower terminals, both terminals excluding a part of these terminals, and the current-limiting element A current limiting element unit consisting of an insulating material integrally coated and molded on the outer peripheral surface of the current limiting element unit is built in.

The present invention proposes an improved structure for mounting the current limiting element unit in such a case, and a bag-shaped storage section 2c that is closed at the front and open at the rear is integrally formed at the rear of the lower part of the main body insulator 2. At the same time, a current limiting element 22 having voltage non-linearity and this current limiting element 2 are further integrated with the housing part 2c.
Both upper and lower terminals 2 are connected to both the upper and lower end surfaces of 2, respectively.
3, 24, and an insulator 25 that integrally covers and molds both terminals 23, 24, excluding a part of both upper and lower terminals 23, 24, and the outer peripheral surface of the current limiting element 22 . A hole-shaped guide portion 2e that connects the upper terminal 23 to the innermost side of the storage portion 2c.
The upper terminal and the lower fixed electrode fixed in the lower recessed part 2a of the main insulator 2 formed adjacent to the upper side of the housing part 2c are inserted into the guide part 2e and the lower part. It is screw-connected by a screw-shaped relay conductor 26 inserted into a through hole 2f that connects the concave notch 2a, and further houses an elastic support ring 32 fitted to the outer peripheral surface of the insulator 25 on the lower terminal side. This invention relates to the structure of a box-shaped high-voltage cutout with a built-in current-limiting element, which is characterized in that it is brought into pressure contact with the inner circumferential surface of the rear open end 2d of the cut-out.

Examples of the present invention will be described in detail below.

1 shows a box-shaped high-voltage cutout with a built-in current-limiting element, and an upper fixed electrode 3, an upper arc extinguishing chamber 4, and an upper electric wire connection terminal 5 are fixed to the upper recessed part 2a of the main body insulator 2 with a metal fitting 6. Similarly, a lower fixed electrode 7, a lower arc-extinguishing chamber 8, and a lower wire connection terminal 9 are fixed to the lower concave cutout 25b with a metal fitting 10. 11 indicates an adhesive. 12 is the axis 13
This is a lid insulator which is pivoted so as to be openable and closable, and a fuse tube 15 is removably mounted on the inner surface of the lid by means of a fitting metal fitting 14. Reference numerals 17 and 18 denote an upper movable electrode and a lower movable electrode of the fuse tube 15, and insertion blades 17a and 18a protruding downward are provided corresponding to the upper and lower fixed electrodes 3 and 7, respectively, on the insulator side of the main body. When the cage lid is closed, it is inserted into the fixed electrode, and when the lid is opened, it is detached to open and close the electric circuit. 19 is a fuse loaded to connect between the upper and lower movable electrodes 17 and 18 of the fuse tube 15; 20 is a shielding plate made of rubber or the like fixed to the rear of the main body insulator 2; 2c is a lid insulator 12
It is a bag-shaped storage part whose opening end 2d is extended to approximately the same extent as the rear opening 12a of the main body insulator 2, and is located at the rear of the lower part of the main insulator 2 and is formed integrally with the insulator body 2. Reference numeral 2e designates a hole-shaped guide portion formed at the innermost portion (front) of the storage portion 2c into which an upper terminal 23 (to be described later) can be inserted, and the guide portion and the lower recessed notch portion 2b are provided on the upper side thereof. A through hole 2f is formed to connect the two. In addition, 21 is a current limiting element unit, which is made of zinc oxide (ZnO).
A current limiting element 22 made of a voltage non-linear resistor whose main component is a current limiting element 22; A discharge portion 24 that contacts the lower end surface 22b and has a protruding tip.
a, and both terminals 23 except for the screw connection part 23a and the discharge part 24a,
24 and an insulating material 25 made of rubber or synthetic resin that integrally covers and molds the outer peripheral surface of the current limiting element 22 . With the 23 side facing forward, the screw connection part 23a is the guide part 2e.
Then, screw the screw-shaped relay conductor 26 inserted into the through hole 2f from the lower recessed part 2b side into the screw connection part 23a to connect the upper terminal 23 to the lower fixed electrode 7. Installed and connected. Reference numeral 27 indicates an elastic conductive piece connecting between the relay conductor 26 and the lower fixed electrode 7.

In the above case, the current-limiting element unit 21 is attached with the discharge part 24a of the lower terminal 24 located at the rear slightly protruding from the open end 2d.
9a is attached to the support bolt 28 on the lower surface 2g of the main insulator 2, and the other end 29b of the ground side mounting bracket 29 is formed to extend backward from the open end 2d.
9b through a discharge gap G. When the cutout is installed, the above-mentioned mounting bracket 29 is attached to the arm of a grounded utility pole and is grounded through the arm. 30 is a mounting nut for tightening and fixing the mounting bracket 29; 31 is a buffer plate interposed between the mounting bracket 29 and the lower surface 2g of the main body insulator 2; and 2h is a mounting nut for tightening and fixing the mounting bracket 29;
This is an engagement protrusion formed on the lower surface 2g of the holder, and serves to restrict the mounting position (direction) of the mounting fitting 29.

Reference numeral 32 denotes a support ring made of a resilient member such as rubber that is fitted onto the outer peripheral surface of the insulator 25 on the lower terminal side. The ring 32 fitted onto the inner wall surface 2i of the storage section 2c
The unit is fixed by resiliently coming into close contact with the unit. 33 is a buffer piece such as kraft paper interposed between the outer peripheral surface of the upper terminal 23 and the inner wall surface of the guide portion 2e, and 34 is a gap between the storage portion 2c formed near the open end 2d after the element unit 21 is inserted. is a sealing material 35 filled in the gap between the guide part 2e in front of the storage part 2c, and the current-limiting element 21
An annular recess 25 in the insulator 25 is used to maintain airtightness between the upper and lower terminals 23 and 24 when assembling the
The same silicone resin sealing material as the sealing material filled in a and 25b is used. 36 is the lower terminal 2
Opening end 2d of storage section 2c excluding discharge section 24a of No. 4
This is a cap-shaped insulating cover made of rubber or synthetic resin that has tracking resistance and heat resistance, and is fitted onto the annular raised portion 2j formed near the opening end 2d, and is further bonded. It is tightly fixed with material. Note that the discharging hole 36a of the insulating cover 36 formed corresponding to the discharging section 24a has its tip protruded largely rearward so that the discharging section 24 is not exposed. Reference numeral 37 denotes a rear electrode closely interposed between the locking step portion of the discharge portion 24a and the inner surface of the insulating cover 36, and this electrode increases the apparent electrode area of the discharge portion 24a and equalizes the electric field in the discharge gap. This ensures that there will be no difference in the discharge starting voltage even if a lightning surge of either positive or negative polarity enters.

In the above configuration, if an abnormal lightning surge enters now, it will be discharged in the discharge gap G, and the surge will be dissipated from the cut-out upper wire connection terminal 5 - upper fixed electrode 3 - upper movable electrode 17 -
Fuse 19 - Lower movable electrode 18 - Lower fixed electrode 7 - Elastic conductive piece 27 - Relay conductor 26 - Upper terminal 2
3 - Current limiting element 22 - Lower terminal 24 - Discharge gap G - The discharge path of the mounting bracket 29 flows to the ground and protects the transformer from dielectric breakdown.

Note that since the lower terminal 24 and the mounting bracket 29 are normally insulated by the discharge gap G, the discharge path is not formed.

The present invention has the above-mentioned configuration, and a bag-shaped storage section 2c whose front side is closed and rear side is open is integrally formed at the rear of the lower part of the main body insulator 2. A current limiting element 22 having non-linearity, upper and lower terminals 23 and 24 connected to both upper and lower end surfaces of the current limiting element 22, respectively;
The current limiting element unit 21 is made up of both the upper and lower terminals 23 and 24, except for a part of them, and an insulator 25 that integrally covers and molds the outer peripheral surface of the current limiting element 22. A lower recessed hole portion of the main body insulator 2 is inserted and stored in a hole-shaped guide portion 2e located at the innermost side of the storage portion 2c, and is further formed adjacent to the upper terminal and the upper side of the storage portion 2c. The lower fixed electrode fixed in the inside of the lower terminal 2a is screw-connected by a threaded relay conductor 26 inserted into the through hole 2f connecting the guide part 2e and the lower recessed part 2a, and the insulation on the lower terminal side is further connected. It consists of a box-shaped high-voltage cut-out structure with a built-in current-limiting element, characterized in that an elastic support ring 32 fitted on the outer peripheral surface of the object 25 is brought into pressure contact with the inner peripheral surface of the rear open end 2d of the storage section. , When the current limiting element unit 21 is built into the housing part 2c of the main body insulator 1, the upper terminal 2 of the unit is
3 is securely attached by a screw-shaped relay conductor 26, and a resilient support ring 32 fitted on the outer circumferential surface of the insulator 25 on the lower terminal 24 side is inserted into the rear open end 2d of the storage portion 2c. Since the current limiting element unit 21 is mounted in pressure contact with the peripheral surface, the current limiting element unit 21 can be mounted reliably.

In addition, when installing the above current limiting element unit 21 , after pushing the unit in, the relay conductor 2
Since the lower fixed electrode 3 and the upper terminal 23 are simply connected by screws at step 6, the installation work can be easily performed, and is thus practically effective.

[Brief explanation of the drawing]

The drawings show an embodiment of the present invention. Fig. 1 is a longitudinal cross-sectional view of a box-shaped high-voltage cutout with a built-in current limiting element showing an embodiment of the invention, and Fig. 2 shows the state before an insulating cover is attached by gluing. Fig. 3 is a structural diagram of the vicinity of the storage part with the insulating cover attached with adhesive, 2...Main insulator, 2a...Top recessed part, 2b...
... lower concave notch, 2c ... storage section, 2d ... open end, 2g ... bottom surface, 2f ... through hole, 3 ... upper fixed electrode, 4 ... arc extinguishing chamber, 5 ... upper wire connection terminal , 7...Lower fixed electrode, 8...Lower arc extinguishing chamber, 9
... Lower electric wire connection terminal, 12 ... Lid body cover, 12
a... opening, 15... fuse tube, 19... fuse, 21 ... current limiting element unit, 22... current limiting element, 22a... upper end surface, 22b... lower end surface, 23... upper terminal, 23a...screw connection part,
24...lower terminal, 24a...discharge part, 25...
Insulator, 26... Relay conductor, 28... Support bolt, 29... Mounting bracket, 29a... One end, 29b
...Other end, 36...Insulating cover, 36a...Discharge hole, G...Discharge gap.

Claims (1)

[Scope of utility model registration request] At the rear of the lower part of the main body insulator 2, there is integrally formed a bag-shaped storage section 2c which is closed at the front and open at the rear, and further includes a current-limiting element 22 having voltage non-linearity with respect to the storage section 2c which is integrally formed. The upper and lower terminals 23 and 24 connected to the upper and lower end surfaces of the current-limiting element 22, respectively, and the outer peripheral surface of the current-limiting element 22 and the upper and lower terminals 23 and 24, excluding a part of the upper and lower terminals 23 and 24, are A current limiting element unit 21 consisting of an insulating material 25 which is integrally coated and molded is stored with the upper terminal 23 inserted into the hole-shaped guide portion 2e located at the innermost side of the storage portion 2c, and further The upper terminal and the lower fixed electrode fixed in the lower recessed part 2a of the main body insulator 2 formed adjacent to the upper side of the housing part 2c are connected to the guide part 2e and the lower recessed part 2.
A is screw-connected by a screw-shaped relay conductor 26 inserted into the through hole 2f that connects to open end 2
A box-shaped high-voltage cutout with a built-in current-limiting element, which is characterized by being brought into pressure contact with the inner peripheral surface of d.