JPH07170633A - Bus duct - Google Patents

Abstract

PURPOSE:To provide a bus duct which is simple to assemble and easy to change a supporting interval of bus bars as required. CONSTITUTION:A connecting fitting 11 of an insulating holder 14 to be disposed down is so engaged with a receptacle fitting 7a fixed under inner wall surfaces of a pair of side plates 7 that protruding end faces of extended part 11b is dropped down. Then, bus bars 9 of each phase are inserted between arbitrary annular flutes of the holder 14 to support lower parts of the bars 9, and the fitting 11 of the holder to be disposed above is so engaged as to drop the end face of the part 11b upward. Eventually, upper end faces of both side plates 7 are covered with cover plates 8, which are clamped by bolts to the plates 7 while pressing the end face of the part 11b of the fitting 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bus duct useful when used as a power supply line having a large current capacity, for example.

[0002]

2. Description of the Related Art As a conventional bus duct, one having a plate-shaped comb-shaped insulating holder having a recess for supporting a bus bar is known. However, when this comb-shaped insulation holder is used for a high-voltage bus duct, the holder is simply formed in a plate shape.Therefore, increase the bus bar distance and the distance between the bus bar and the housing wall surface to secure the creepage distance. There is a need to. Therefore, the bus duct becomes larger by that amount, and there is a problem in terms of installation space and economy. In addition, as shown in FIG. 2, a high-voltage bus duct having a structure in which a plurality of insulators 2 are fixed in a housing 1 and each bus bar 4 is supported by the pressure of a support metal fitting 3 mounted on these insulators 2 has been put into practical use. However, in the bus duct having such a structure, since the support fitting 3 is formed wide to support the bus bar 4, it is necessary to secure a predetermined interphase distance and ground distance. Also, it is necessary to increase the distance between the housing 1 and the support fitting 3, which in turn has the drawback that the bus duct becomes large in size as described above, and since the support fitting is used for each bus bar, the number of parts is small. As a result, the number of bus ducts becomes large, and it takes a lot of time and labor to assemble the bus duct. By the way, in Japanese Utility Model Laid-Open No. 56-63218, an insulating holder having a quadrangular cross section is arranged in a non-contact state with a wall surface inside a housing via a buffer, and a concave groove is provided on surfaces of the insulating holder which face each other. A high-voltage bus duct having a structure in which a buffer body is provided and the busbar is supported through the buffer body is shown. Then, when the insulating holder and the cushioning body are combined in this way, leg portions for attaching the spacing cushioning body are formed at both ends of the insulating holder,
Further, by providing or embedding a protrusion for increasing the creepage distance in the insulating holder, each creepage distance between the phase and the ground can be increased. Therefore, even if the bus bar interval and the space between the bus bar and the housing wall surface are reduced, a sufficient creeping distance can be ensured, so that the bus duct can be downsized. However, when the legs or protrusions for increasing the creepage distance are provided in the insulating holder or the protrusions are embedded in the holder, the holder shape becomes complicated, so the holder must be manufactured by die processing rather than mechanical processing. Therefore, the unit price of each holder becomes expensive, which is uneconomical. Further, as described above, when the buffer body for separating and supporting the bus bar is used, the number of man-hours for assembling the bus duct increases, which requires time and labor for the work, and further, an insulating holder having a rectangular cross section is required. When it is used, dust easily adheres to its upper surface, which also has a drawback that it causes a creeping flash on the surface. Therefore, the present applicant proposes a bus duct in which the bus bar 9 is supported by upper and lower cylindrical cylindrical insulating holders 10 having a plurality of annular grooves 10a for supporting the bus bar as shown in FIG. (Practical application Sho 59-8906
No. 3). By the way, when the bus duct having such a structure is connected to a transformer or a switchboard as shown in FIG. 4, the distance l1 between the conductors 13 of the electrical equipment such as the transformer or switchboard is reduced.
Is larger than the distance l2 between the bus bars 9 of the bus duct,
It is necessary to increase the distance between the annular grooves 10a of the insulating holder 14 that supports the connecting bus bar 9 '. However, in order to connect the bus duct to the transformer, the switchboard, or the like, it is necessary to manufacture a new insulating holder 14 suitable for this, because a new mold, a manufacturing jig, or the like is required.
There are disadvantages that are economically disadvantageous.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of such a point, and provides a bus duct which is easy to assemble and which can easily change a supporting interval of bus bars as needed. Is intended.

[0004]

The bus duct of the present invention comprises:
The upper and lower insulating holders, which have the same number of annular folds on the peripheral surface at the same interval along the axial direction and have the same axial thickness, respectively, are used to move the bus bar above and below the bus bar. Ends are supported as if they are arranged between the annular folds, and engaging fittings provided at both ends of each insulating holder are receiving fittings provided on opposite side surfaces of the housing. It is characterized in that each is engaged.

[0005]

In the bus duct of the present invention, the fittings attached to both ends of the cylindrical insulating holder are fitted into the receiving fittings provided on the opposite wall surfaces of the housing.
The assembly work of the bus duct can be efficiently performed in a short time. Further, by forming the insulating holder in a cylindrical shape and providing a plurality of annular grooves for supporting the busbars on the peripheral surface thereof, it is possible to effectively prevent dust from adhering to the insulating holders, and in addition, between the busbars. Since there is an annular crease for securing the creepage distance, it is possible to sufficiently secure the creepage distance by using the insulating holder without using any other member, even if the bus bar interval or the like is reduced. Furthermore, since the insulating holder has a simple structure in which an annular fold is provided on the cylinder or column,
Its production is very easy. Therefore, it is possible to provide an inexpensive bus duct with excellent electrical characteristics, and
Since the number of parts of the bus duct is small, the transport cost is reduced accordingly, and even the bus duct for high voltage can support the bus bar only with the insulating holder,
It has the same structure as the low-voltage bus duct, so that common jigs can be used. Furthermore, since the annular folds are formed at equal intervals, it is possible to easily change the support interval of the busbars, and thus a biduct that can be easily connected to a transformer, switchboard, etc. without the need to manufacture a new insulating holder. Can be provided. Further, when at least 7 annular folds are formed, at least 6 annular grooves are formed by these annular folds, so at least 6 bus bars can be arranged between the upper and lower insulating holders. Furthermore, since at least two busbars can be arranged for each phase, it is possible to provide a bus duct that can easily cope with an increase in current capacity without preparing a new insulating holder.

[0006]

Embodiments of the present invention will now be described in detail with reference to the drawings. FIG. 1 shows an example in which the present invention is applied to a high-voltage bus duct, and the bus duct according to the present invention includes a housing 5. The housing 5 includes a bottom plate 6, a pair of side plates 7 and 7 fixed to both sides of the bottom plate 6 so as to face each other along the longitudinal direction thereof, and a lid plate fixed to the side plates 7 and 7. 8 and. In this housing 5, a plurality of bus bars 9 are arranged in parallel along the side plate 7, and each bus bar 9 is supported by insulating holders 14, 14 which are vertically opposed to each other. ◎
As shown in FIG. 1, FIG. 5 and FIG. 6, each insulating holder 14 is formed in a cylindrical shape, and the fittings 11, 11 are attached to both ends thereof. The engaging fitting 11 extends in the radial direction of the insulating holder 14 and a semicircular portion 11a formed to have a smaller diameter than the outer diameter of the insulating holder 14, and projects slightly in the radial direction from the outer peripheral surface of the insulating holder 14. The bonding agent 1 such as cement is used to connect the peripheral wall of the protruding portion 11c protruding into the insulating holder 14 and the inner peripheral wall of the insulating holder 14 including the extending portion 11b.
It is attached to the insulating holder 14 by being fixed via 2. And on the peripheral surface of the insulating holder 14,
A large number of annular folds 10b for supporting each bus bar 9 are provided at equal intervals 13 along the axial direction. Further, the axial thickness t of each annular fold 10b is also made uniform. Next, a process of assembling the high-voltage bus duct according to the present invention will be described. That is, the metal fittings 11a of the insulating holder 14 to be arranged below are attached to the receiving metal fittings 7a, 7a fixed to the lower inner wall surfaces of the pair of side plates 7, 7 by attaching the protruding end surfaces of the respective extending portions 11b, 11b. Engage as if dropping downwards. Thereby, the extension parts 11b, 11b
Insulation holder 1 with its protruding end face in contact with bottom plate 6
4 can be arranged below the housing 5. Next, any annular folds 1 of the insulating holder 14 arranged above
The busbar 9 of each phase is inserted between 0b to support the lower part of the busbar 9 and the bracket 7 fixed above the side plates 7 and 7.
The fittings 11 and 11 of the insulating holder 14 to be arranged above are inserted into a and 7a so that the projecting end surfaces of the extension portions 11b and 11b are dropped upward. As a result, the upper portion of the bus bar 9 of each phase can be inserted and supported between the annular folds 10b at positions corresponding to the insulating holder below the insulating holder 14. In this case, since the extended portions 11b of the engaging fittings 11 of the upper insulating holder 14 project beyond the outer circumference of the holder 14, the extended portions 11b project slightly upward from the upper end surface of the side plate 7. Finally, the upper end surfaces of the both side plates 7, 7 are covered with the cover plates 8, and the cover plates 8 are attached to the extended portions 11b, 11 of the fittings 11, 11.
While pressing the end face b, the side plates 7 and 7 are fixed with bolts (not shown). In the high-pressure bus duct of the present invention assembled in this manner, since there are a plurality of annular folds 10b for securing creepage distances between the busbars 9, the busbars 9 are arranged in close proximity to each other, and Side plate 7
Even if the distance between the inner wall surface and the inner wall surface is small, a sufficient creeping distance can be secured. Therefore, the high-voltage bus duct of the present invention has a duct cross-sectional area of about 1/3 of that of the conventional bus duct of this type, and is small in size. Also, the insulation holder 14
As a result of the presence of the annular crease for securing the creepage distance, the insulating holder 14 is simply dropped into the housing 5 without using any other member such as a cushioning member as described above, and the cover plate 8 is disposed. You can assemble the bus duct just by bolting it, so the assembly work is easy,
And it can be completed in a short time. Further, when the insulating holder 14 is formed in a cylindrical shape or a cylindrical shape, dust is hardly attached to the holder 14, so that there is almost no risk of creeping flash on the surface due to dust, and it is curved because it is hollow. Therefore, it is possible to effectively prevent the internal pressure from rising. If the insulating holder 14 is formed in a cylindrical shape or a cylindrical shape and has a simple structure in which the annular folds 10b are provided on the peripheral surface, the insulating holder 14 has a symmetrical shape. For example, the insulating holder 14 according to the present invention can be produced only by forming the circumferential folds on the circumferential surface of the cylindrical material with a lathe. Therefore, coupled with the small size and the small number of parts, the bus duct can be provided at a very low cost. By the way, when the extending portion 11b of the fitting 11 is projected from the outer periphery of the holder 14, as described above, the lid plate 8 can be bolted while pressing the end surface of the extending portion 11b. The insulating holders 14 and 14 of FIG. Therefore, even if the bus duct of the present invention is laid vertically, the bus bar 9 does not come off the holder and fall from the bus duct.
In the above embodiment, the insulating holder 14 may be made of an insulating material such as porcelain or epoxy, and may be made of an inorganic material having good tracking resistance. Needless to say, either a bare busbar or an insulating coated busbar may be used as the busbar 9. In addition, in the above-described embodiment, the case where the insulating holder 14 shown in FIG. 1 is formed as an integral body has been described, but the present invention is not limited to this, and is shown in FIGS. 7 and 8, for example. As described above, the divided insulating holders 14a, 14b, 14a 'and 1 having the same structure are
Prepare at least two 4b ', and one end portion 11 of each of them,
You may connect and form 1, 10c, and 10c.
In this case, it is desirable that the thickness of the engaging fitting 11 or the annular fold 10c in the connected portion in the axial direction be about half of that in the non-connected portion. In the figure, 15 is a connecting metal fitting embedded in the center of one end of the split insulating holders 14a ', 14b' via a cement 16 such as cement, and 17, 18 are
It shows a connecting bolt screwed into a screw formed on the engaging fitting 11 and the connecting fitting 15. In the above-mentioned embodiment, the high-voltage bus duct is described,
The present invention is not limited to this, and may be applied to a low pressure bus duct.

[0007]

According to the present invention, the insulating holder engaging fitting is engaged with the receiving fitting of the housing, so that the assembling work can be performed efficiently in a short time. In addition, since the insulating holder has a cylindrical shape and the peripheral surface thereof is provided with a plurality of annular grooves for supporting the busbar, it is possible to effectively prevent dust from adhering to the insulating holder. In addition, it is possible to secure a sufficient creeping distance even if the bus bar interval is reduced. Further, since the insulating holder has a simple structure in which an annular fold is provided on the cylindrical body or the columnar body, its manufacture is very easy. Therefore, it is possible to provide a bus duct that is inexpensive and has excellent electrical characteristics, and since the number of parts of the bus duct is small,
Transport costs are reduced by that amount, and even for high-voltage bus ducts, if the busbar is supported only by the insulating holder as described above, the structure will be the same as the low-voltage bus duct. Can also be used. Further, in the present invention, since the annular folds are formed at equal intervals, it is possible to easily change the support interval of the busbars, and thus it is possible to easily connect to the transformer, switchboard, etc. without manufacturing a new insulating holder. A bus duct can be provided. Further, since a large number of annular folds are formed, it is possible to arrange at least two busbars per phase, and it is possible to easily cope with an increase in current capacity without preparing a new insulating holder. A bus duct can be provided.

[Brief description of drawings]

FIG. 1 is a sectional view of a bus duct according to the present invention.

FIG. 2 is a sectional view of a conventional bus duct.

FIG. 3 is a sectional view of a conventional bus duct.

FIG. 4 is an explanatory view showing a connection state between bus bars of a bus duct and bus bars of a transformer or the like.

FIG. 5 is a vertical sectional view of an insulating holder used in the present invention.

6 is a side view of the insulation holder shown in FIG.

FIG. 7 is a cross-sectional view of main parts showing another embodiment of the insulating holder.

FIG. 8 is a sectional view of an essential part showing another embodiment of the insulating holder.

[Explanation of symbols]

 5 ... Housing 7 ... Side plate 7a ... Bracket 8 ... Lid plate 9 ... Bus bar 10b ... Annular fold 11 ... Engagement metal fitting 14 ... Insulation holder

Claims (1)

[Claims] 1. A bus duct comprising a plurality of bus bars arranged in a housing along a longitudinal direction thereof, and a pair of insulating holders for supporting upper and lower ends of the bus bars along the longitudinal direction at predetermined intervals. In the above, on the peripheral surface of each of the insulating holders, at the same intervals along the axial direction,
In addition, several other annular folds are formed so that each of them has the same axial thickness. Further, at both ends of each of the insulating holders, there are receivers provided on opposite sides of the housing. Bus ducts, characterized in that there are provided fittings for fitting into the fittings, and the fittings of the respective insulating holders are fitted into the receiving fittings by dropping the insulating holders into the housing. .