JP2011066107A - Oil-filled electric apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an oil-filled electric apparatus such that an oil leak preventive cover can be easily attached to an accessory even when the oil-filled electric apparatus is an on-site assembling type article. <P>SOLUTION: This invention relates to the oil-filled electric apparatus including a case filled with insulating oil, and accessories fixed to a side part of the case via a gasket by clamping bolts, wherein the oil leak preventive cover to which stud bolts are attached instead of an arbitrary plurality of bolts among the bolts clamping the accessories and which has stud bolt insertion holes formed corresponding to the stud bolts is mounted via the gasket so as to cover the respective accessories by threadably engaging clamping nuts with the stud bolts protruding from a tip surface of the oil preventive cover and clamping them. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an oil-filled electrical device including an accessory attached via a packing to a mounting seat welded to a side surface of a case filled with insulating oil.

  As shown in Patent Document 1, Patent Document 2 or Patent Document 3, the oil-filled electrical apparatus includes a thermometer that monitors the temperature of the tap position viewing window and insulating oil so that the tap position can be confirmed from the outside of the case. In addition, accessories such as an oil level gauge for monitoring the oil level position of the insulating oil are mounted. Accessories for these tap position viewing windows, thermometers, oil level gauges, etc. are packed on each mounting seat having a plurality of tap holes welded to the periphery of each notch formed on the side of the case. It is oil-tightly mounted by tightening with bolts.

  For example, as disclosed in Patent Document 1, an automatic voltage regulator for power distribution that is an oil-filled electrical device includes a transformer with a tap, a tap changer at the time of switching taps of the transformer with a tap, and a tap changer at the time of load. And a tap position display plate that mechanically displays the tap position in conjunction with the oil, and these are housed in the case filled with insulating oil together with the filled insulating oil, and an automatic voltage regulator for power distribution The tapping position can be checked outside the case at the time of operation and inspection.

  As shown in FIGS. 3A and 3B, the tap position viewing window 1a of the automatic voltage regulator for power distribution includes a mounting seat 2, a transparent member 3, a window frame 4, and packings 5a and 5b. The mounting seat 2 is formed of a circular notch 6a formed on a side surface of the case 6 with a metal plate having a relatively large thickness formed in a circular ring shape and one flat surface of the circular shape facing the case 6. A plurality of tap holes 7 are formed at predetermined intervals in the circumferential direction on the other flat surface of the circle. The transparent member 3 is formed of an acrylic plate or the like in a circular shape, the window frame 4 is formed of a metal plate or the like in a circular ring shape, and the packings 5a and 5b are formed in a circular shape. Bolt through-holes 8 are respectively formed corresponding to the tap holes 7 formed in. In the window frame 4, the packing 5 a, the transparent member 3, and the packing 5 b are sequentially interposed in the mounting seat 2, and the bolt 9 is inserted into the bolt through hole 8 formed in the window frame 4 and screwed into the tap hole 7. It is attached by tightening.

JP 2006-179680 A (FIG. 14) Japanese Patent Laid-Open No. 9-46828 (FIG. 1) Japanese Patent Laid-Open No. 52-151977 (FIG. 1)

  However, in oil-filled electrical equipment, it is often used for 30 years or more, and with the passage of time, the packing interposed in the tap position viewing window, thermometer, and oil level gauge deteriorates and the oil tightness decreases. As a result, there is a problem that an oil leak (oil leak is about the extent of oil oozing) occurs.

  Therefore, as a countermeasure against oil leakage, periodic replacement of the packing in 10 to 15 years is recommended. However, the replacement of packing is performed when the oil level of the insulating oil in the case is at the tap position viewing window, thermometer, oil It is necessary to pull out until it is below the packing interposed in the accessories such as the surface gauge, and to remove the accessories such as the tap position observation window, thermometer, and oil level gauge. Moreover, about the oil-filled electrical equipment installed on the pillar, not only the power failure work but also the descending pillar work is necessary, and there is a problem that much labor and cost are required.

  The object of the present invention is to prevent the insulating oil leaking from the accessories attached to the case from leaking out of the case without performing power outage work, oil removal work or packing replacement work. It is to provide an oil-filled electrical device.

  According to a first aspect of the present invention, a bolt is inserted through a packing into a mounting seat having a case filled with insulating oil and a plurality of tap holes welded to the periphery of a notch formed in a side portion of the case. Targeting oil-filled electrical equipment with accessories such as a tapping position viewing window, a thermometer, or an oil level gauge that are tightened and fixed, to any of the bolts that are tightening the accessories A stud bolt is attached instead, and an oil leakage prevention cover having a stud bolt insertion hole formed corresponding to the stud bolt is inserted into the stud bolt, and tightened to the stud bolt protruding from the front end surface of the oil leakage prevention cover. The oil leakage prevention cover is attached so as to cover the respective accessories by screwing and tightening the attached nuts.

  According to a second aspect of the present invention, a notch is formed in the tip surface of the oil leakage prevention cover, and a transparent member such as an acrylic plate is attached and fixed so as to close the notch.

  In a third aspect of the invention, the oil leakage prevention cover is formed of a transparent member such as an acrylic plate.

  According to a fourth aspect of the present invention, a coil spring and a presser plate are loosely fitted to the stud bolt protruding from the front end surface of the oil leakage prevention cover, and a tightening nut is screwed onto the stud bolt to tighten. The coil spring is pressed to the case side.

  As described above, according to the first invention, a stud bolt and a nut are provided for an oil-filled electrical device that is an existing local product that is likely to cause oil leakage from an accessory attached to the device. This makes it possible to easily attach the oil leakage prevention cover to the accessory and prevent leakage of the insulating oil to the outside of the case, eliminating the need for power outage work, oil removal work and packing replacement work. Column work is also unnecessary, and labor and cost can be greatly reduced.

  According to the second invention, in addition to the effects of the first invention, the tap position, the temperature of the insulating oil or the oil surface position of the insulating oil can be confirmed from the outside of the oil leakage preventing cover without removing the oil leakage preventing cover. can do.

  According to the third invention, in addition to the effects of the first invention and the second invention, the notch portion is formed on the front end surface of the oil leakage prevention cover, or the notch portion is made of a transparent member such as an acrylic plate. The work of closing is unnecessary, the oil leakage prevention cover can be easily formed, and the cost can be reduced.

  According to the fourth invention, in addition to the effects of the first invention, the second invention, and the third invention, the flange portion of the oil leakage prevention cover is pressed against the case by the coil spring loosely fitted to the stud bolt. Therefore, even if the elastic force of the packing interposed between the case and the flange portion decreases, the surface pressure can be constantly applied to the flange portion for a long period of time, and the oil leakage prevention life of the oil leakage prevention cover Can be extended.

(A) is a front view which shows the principal part which showed an example of preferable embodiment of the oil-filled electrical equipment concerning this invention, (B) is the AA sectional view taken on the line in FIG. (A) is a front view which shows the principal part of other embodiment of the oil-filled electrical equipment concerning this invention, (B) is an AA sectional view taken on the line in FIG. (A) is a front view which shows the principal part of the oil-filled electrical equipment which has the conventional tap position observation window, (B) is an AA sectional view taken on the line in FIG.

Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.
(First embodiment)
1A and 1B show the configuration of the main part of the first embodiment of the present invention using an automatic voltage regulator for power distribution. The basic configuration of the tap position inspection window 1a shown in FIG. 1 is the same as that of the tap position inspection window 1a shown in FIG. 3, and includes a mounting seat 22, a transparent member 23, a window frame 24, and packings 25a and 25b. The attachment seat 22 is attached by welding to a circumferential circle of a notch 6a formed on the side surface of the case 6, and a plurality of tap holes 27 are formed. Bolt through holes 28 are formed in the window frame 24 so as to correspond to the tap holes 27 formed in the mounting seat 22. The window frame 24 is attached by inserting a bolt 29 into the bolt through hole 28, screwing it into the tap hole 27, and tightening.

  An oil leakage prevention cover 30 is disposed outside the tap position inspection window 1a so as to cover the tap position inspection window 1a, and is screwed onto the stud bolts 31a, 31b, 31c and the stud bolts 31a, 31b, 31c. The fastening nuts 32a, 32b, and 32c are fixed. The stud bolts 31 a, 31 b, and 31 c are set to be longer than the height of the oil leakage prevention cover 30. A stud bolt insertion hole 33 is formed on the front end surface of the oil leakage prevention cover 30 so as to correspond to the stud bolts 31a, 31b and 31c, and a flange portion 35 for interposing the packing 34 is formed on the lower end portion. ing.

(Second Embodiment)
FIG. 2 shows the structure of the main part of the oil leakage prevention cover 30 used in the second embodiment of the present invention. In this embodiment, the notch 30a is formed in the front end surface of the oil leakage prevention cover 30, and the flange part 37 is formed in the notch 30a. A transparent member 38 such as an acrylic plate is placed on the flange portion 37 so as to close the notch portion 30a, and is attached and fixed by an adhesive. Other configurations are the same as those of the embodiment shown in FIG.

  When the transparent member 38 such as an acrylic plate is attached and fixed as described above, it is preferable to use a silicon-based resin such as a sealant from the viewpoint of water tightness and air tightness as an adhesive to be bonded.

(Third embodiment)
In the third embodiment of the present invention, the oil leakage prevention cover 30 shown in FIG. 1 is formed of a transparent member such as an acrylic plate. Other configurations are the same as those of the embodiment shown in FIG.

(Fourth embodiment)
In the fourth embodiment of the present invention, as shown in FIGS. 1 and 2, the coil spring 39 and the presser plate 40a are attached to the stud bolts 31a, 31b, 31c protruding from the front end surface of the oil leakage prevention cover 30. , 40b, 40c are loosely fitted, and the tightening nuts 32a, 32b, 32c screwed to the stud bolts 31a, 31b, 31c are tightened to press the coil spring 39 toward the case. Other configurations are the same as those of the embodiment shown in FIGS.

  The procedure for attaching the oil leakage prevention cover 30 to the accessory 1 for the existing and new oil-filled electrical equipment is as follows. First, an arbitrary plurality of bolts 29 (in the example shown in the drawing) are tightened. The three bolts 29 are removed, one of the stud bolts 31a, 31b, 31c is screwed into the plurality of tap holes 27 after the bolt 29 is removed, and then the fixing nut 41 is tightened to tighten the stud bolts 31a, 31b. , 31c. Next, the oil leakage prevention cover 30 in which the stud bolt insertion holes 33 are formed corresponding to the stud bolts 31a, 31b, and 31c is inserted into the stud bolts 31a, 31b, and 31c. Next, the coil spring 39 and the presser plates 40a, 40b, and 40c are loosely fitted to the stud bolts 31a, 31b, and 31c protruding from the front end surface of the oil leakage prevention cover 30, and tightened to the other stud bolts 31a, 31b, and 31c. The attachment nuts 32a, 32b, and 32c are screwed and tightened to be attached so as to cover the respective accessories 1 in which oil leakage is a concern.

DESCRIPTION OF SYMBOLS 1 Accessory 1a Tap position observation window 6 Case 6a Notch 22 Mounting seat 23 Transparent member 24 Window frame 25a, 25b Packing 27 Tap hole 28 Bolt through-hole 29 Bolt 30 Oil leakage prevention cover 30a Notch 31a, 31b, 31c Stud Bolts 32a, 32b, 32c Tightening nut 33 Stud bolt insertion hole 34 Packing 35 Flange portion 37 Flange portion 38 Transparent member 39 Coil springs 40a, 40b, 40c Holding plate 41 Fixing nut

Claims (4)

A tap that is fastened with bolts via a packing to a mounting seat that has a case filled with insulating oil and a plurality of tap holes welded to the periphery of the notch formed on the side of the case. In oil-filled electrical equipment equipped with accessories such as a position inspection window, thermometer or oil level gauge,
A stud bolt is attached in place of any of the plurality of bolts tightening the accessory, and an oil leakage prevention cover in which stud bolt insertion holes are formed corresponding to the stud bolts is attached to the stud bolt. The oil leakage prevention cover is attached via a packing so as to cover the respective accessories by inserting and tightening a nut to a stud bolt protruding from the front end surface of the oil leakage prevention cover and tightening the nut. Oil-filled electrical equipment characterized by 2. The oil-filled electricity according to claim 1, wherein a cutout portion is formed at a front end surface of the oil leakage prevention cover, and a transparent member such as an acrylic plate is attached so as to close the cutout portion. machine.   The oil-filled electrical device according to claim 1, wherein the oil leakage prevention cover is formed of a transparent member such as an acrylic plate. A coil spring and a presser plate are loosely fitted to the stud bolt protruding from the front end surface of the oil leakage prevention cover, and a nut is screwed into the stud bolt and tightened to tighten the coil spring toward the case. The oil-filled electrical device according to claim 1, 2, or 3.

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