JPH055800Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Technical Field of the Invention) The present invention relates to a bus duct used as a power supply line with a large current capacity.

(Technical background of the invention and its problems) As a conventional bus duct, one is known that includes a plate-shaped comb-shaped insulating holder having a recess for supporting a conductor. However, when this comb-shaped insulating holder is used in a high-voltage bus duct, since the holder is simply formed into a plate shape, the distance between the conductors and the distance between the conductor and the housing wall must be increased to ensure creepage distance. There is a need to. Therefore,
Since the bus duct is correspondingly larger, there are problems in terms of installation space and economy.

In addition, as shown in Fig. 4, a high-voltage bus duct has been commercialized in which a plurality of insulators 2 are fixed in a housing 1 and each conductor 4 is supported by the clamping force of a support fitting 3 attached to these insulators 2. has been done. In the bus duct having such a structure, the supporting metal fittings 3 are formed wide to support the conductors 4, so in order to ensure a predetermined interphase distance and ground distance, the mutual spacing between the supporting metal fittings 3 and the distance between the housing 1 and the supporting metal fittings 3 are required. It is necessary to increase the distance between Therefore, the bus duct becomes large in size as described above. In addition, since the number of parts increases when insulators and supporting metal fittings are used for each conductor, it takes a lot of time and effort to assemble the bus duct, and the bus duct itself becomes expensive. cannot be avoided.

By the way, in Japanese Utility Model Application Publication No. 56-63218, an insulating holder with a rectangular cross section is disposed in a housing without contacting the wall surface via a buffer, and grooves are formed on mutually opposing surfaces of the insulating holder. A high-voltage bus duct is shown that has a structure in which a buffer body is provided and a conductor is supported through the buffer body. When the insulating holder and the buffer are combined in this way, legs are formed at both ends of the insulating holder to attach the above-mentioned spacing buffer, and the insulating holder is provided with protrusions or buried to increase the creepage distance. By doing so, each creepage distance between the phases and the ground can be increased. Therefore, even if the conductor spacing and the spacing between the conductor and the housing wall surface are reduced, a sufficient creepage distance can be ensured, making it possible to downsize the bus duct. However, if the insulating holder is provided with legs or protrusions to increase the creepage distance, or if the holder is structured to bury the protrusions, the holder shape becomes very complicated.
The holder must be made by mold processing rather than mechanical processing, and therefore the unit price for each holder becomes very high, which is uneconomical. Furthermore, as described above, when using buffers for separating and supporting conductors, the number of man-hours required for assembling the bus duct increases, resulting in labor and time required for the work. Furthermore, when an insulating holder with a rectangular cross section is used, dust tends to adhere to the upper surface of the insulating holder, which has the disadvantage of causing creeping flash.

On the other hand, a bus duct equipped with a cylindrical insulating holder is known (Utility Application No. 153850-1981). This bus duct includes a structure in which a conductor 6 is supported by an insulating holder 10 having an annular groove 11, holes are provided in the side plates 2 and 3, the insertion holes 12 of the insulating holder 10 are aligned with these holes, and bolts 13 and 14 are inserted. It is assembled by inserting and tightening.

However, a bus duct with such a structure has only one bolt.
If the tightening force of 3 and 14 is large, the insulating holder 10
There is a risk of damaging it. Also, the work of aligning the insertion hole 12 of the insulating holder 10 with the holes of the side plates 2 and 3, and maintaining this alignment state, the bolt 1
3 and 14 are required, and iron plate 1
Temporarily tighten the bolts at the bottom of the side plates 2 and 3, align the lower insulating holder 10, insert and temporarily tighten the bolts 14, align the upper insulating holder 10,
Insertion and temporary tightening of bolts 13, side plate 2 of iron top plate 9,
3 Perform each step of tightening the bolts to the upper end in this order,
Finally, each temporarily tightened bolt must be tightened to a predetermined torque to prevent deformation of the housing, which requires a great deal of effort and time for assembly.

(Objective of the invention) An object of the invention is to provide a bus duct that is easy to assemble and has a compact structure while effectively preventing the occurrence of creeping flash.

(Summary of the invention) The present invention consists of a plurality of conductors disposed inside the housing along its longitudinal direction, and a cylindrical housing provided with a plurality of annular grooves that support both ends of each conductor along the longitudinal direction. The bus duct is equipped with an insulating holder and is characterized in that the engaging fittings attached to both ends of the insulating holder are engaged with receiving fittings provided on opposing walls of the housing.

(Embodiments of the invention) Hereinafter, embodiments of the invention will be described in detail with reference to the drawings.

FIG. 1 shows an example in which the present invention is applied to a high-pressure bus duct, and the bus duct according to the present invention includes a housing 5. This housing 5 is
A bottom plate 6, and a pair of side plates 7, 7 fixed to opposite sides of the bottom plate 6 along its longitudinal direction.
and a lid plate 8 fixed on these side plates 7, 7. Inside this housing 5, a plurality of conductors 9 are arranged in parallel along the side plate 7, and each conductor 9 is arranged in an insulating holder 1 arranged vertically facing each other.
0,10.

Each insulating holder 10 is shown in FIGS. 1 and 2 a,
As shown in b, it is formed into a cylindrical shape, and engagement fittings 11, 11 are attached to both ends. Engagement fitting 1
1 includes a semicircular part 11a formed to have a smaller diameter than the outer diameter of the insulating holder 10, and an extension part 11b extending in the radial direction of the holder 10 and slightly protruding in the radial direction than the outer peripheral surface of the holder 10. It is attached to the holder 10 by fixing the peripheral wall of the protrusion 11c that projects into the holder 10 and the inner peripheral wall of the holder 10 via a bonding agent 12 such as cement. A plurality of annular grooves 10 are provided on the circumferential surface of the insulating holder 10 to support each conductor 9.
a are provided at equal intervals along the axial direction, and a plurality of annular grooves 10b for ensuring creepage distance are provided between these annular grooves 10a and on both end sides.

On the other hand, receiving metal fittings 7a are fixed to upper and lower positions of the opposing wall surfaces of the side plates 7,7. These receiving fittings 7a are formed in a U-shape, and the bent portions at both ends protrude in a direction perpendicular to the plate surface of the side plate 7.

Next, the assembly process of the high-pressure bus duct according to the present invention will be explained.

That is, the lower ends of the side plates 7, 7 are fixed to both ends of the bottom plate 6 with bolts, etc., and the insulating holder 10 to be disposed below is placed on the receiving metal fittings 7a, 7a fixed below each side plate 7, 7. The engaging fittings 11, 11 are inserted so that the protruding end surfaces of the extension portions 11b, 11b are directed downward, respectively. Thereby, the insulating holder 10 can be disposed below the housing 1 with the protruding end surfaces of the respective extensions 11b, 11b in contact with the bottom plate 6.

Next, the conductors 9 of each phase are inserted into the supporting annular grooves 10a of the insulating holder 10 arranged above to support the lower part of the conductors 9, and are attached to the receiving fittings 7a, 7a fixed above the side plates 7, 7. The engaging fittings 11, 11 of the insulating holder 10 to be placed above are inserted so that the protruding end surfaces of the respective extension portions 11b, 11b are directed upward and dropped. Thereby, the upper part of the conductor 9 of each phase can be inserted into each supporting annular groove 10a of the insulating holder 10 and supported. In this case, both engagement fittings 11 of the upper insulating holder 10
Since the extended portion 11b protrudes beyond the outer periphery of the holder 10, the extended portion 11b slightly protrudes upward from the upper end surface of the side plate 7.

Finally, cover the upper end surfaces of the side plates 7, 7 with the cover plate 8, and attach the cover plate 8 to the side plates 7, 7 with the fittings 11, 1.
While pressing the end faces of the extension parts 11b and 11b of 1, they are fixed with bolts.

Now, in the high-voltage bus duct of the present invention assembled in this way, the conductor 9 is supported using the insulating holder 10 having a plurality of annular grooves 10b on the circumferential surface for ensuring creepage distance. Even if the conductor 9 and the inner wall surface of the side plate 7 are arranged close to each other and the distance between the conductor 9 and the inner wall surface of the side plate 7 is reduced, a sufficient creepage distance can be ensured. Therefore, the high-pressure bus duct of the present invention has a duct cross-sectional area that is approximately 1/3 that of conventional bus ducts of this type, making it more compact. Furthermore, if the insulating holder 10 is provided with an annular groove for ensuring creepage distance, as described above, there is no need to use any other members such as a buffer, and the insulating holder 10 can be dropped into the housing 1 and engaged. Since the bus duct can be assembled by simply placing the metal fitting into the receiving metal fitting 7a and bolting the cover plate 8, the assembly work can be completed easily and in a short time. Furthermore, if the insulating holder 10 is formed into a cylindrical shape, the adhesion of dust to the holder 10 is extremely reduced, so there is almost no risk of creeping flash due to dust, and since it is hollow, it will not curve, making it easier to use. Therefore, an increase in internal pressure can be effectively prevented. The insulating holder 10 is formed into a cylindrical shape, and has annular grooves 10a, 10a on the circumferential surface.
If the insulating holder 10 has a symmetrical structure, the structure of the present invention can be easily achieved by simple machining, for example, by forming a circumferential groove on the circumferential surface of a cylindrical material using a lathe. An insulating holder 10 can be created. Therefore, small size,
Combined with the small number of parts, the bus duct can be provided at a very low cost.

By the way, if the extension part 11b of the engagement fitting 11 is made to protrude from the outer periphery of the holder 10, as described above, the cover plate 8 can be bolted while pressing the end face of the extension part 11b, so that each conductor 9 can be fixed vertically. The insulating holders 10, 10 can reliably clamp and support. Therefore, even if the bus duct of the present invention is installed vertically, the conductor 9 will not come off the holder and fall from the bus duct.

In the above embodiment, the insulating holder 10 may be made of an insulating material such as porcelain or epoxy, or may be made of an inorganic material with good tracking resistance.

It goes without saying that the conductor 9 may be either a bare conductor or an insulated conductor.

FIG. 3 shows an example in which the present invention is applied to a two-stage high-pressure bus duct. That is, in this application example, the conductors 9 of each phase are separately arranged in two stages, upper and lower, and the plurality of conductors 9 in the upper stage are used for supporting each of the upper and central cylindrical insulating holders 10, 10. The lower conductors 9 are supported in the housing 1 by the grooves 10a, and the lower conductors 9 are supported by the supporting grooves 10a of the central and lower cylindrical insulating holders 10, 10. In this way, by forming the insulating holder 10 into a cylindrical shape and providing the annular grooves 10a, 10a on the circumferential surface, the insulating holder 10 can be used in the upper and lower parts without using an insulating holder having a special shape in the center. By simply disposing an insulating holder 10 identical to 10 in the center, the conductors 9 of each phase can be separated and supported in two stages. Therefore, since it is sufficient to use a type of insulating holder, mass production of holders can be achieved.
Furthermore, assembly errors will not occur.

Although the above two embodiments show examples in which the present invention is applied to high-pressure bus ducts, the present invention can also be applied to low-pressure bus ducts. In this case, the insulating holder 10 has an annular groove 10 for supporting the conductor.
It is sufficient to provide only a.

(Effects of the invention) According to the invention, the fittings attached to both ends of the cylindrical insulating holder are made to fit into the receiving fittings provided on the opposing walls of the housing, ensuring a sufficient creepage distance. However, it is possible to provide a bus duct that can be assembled in a short time and with good workability. Therefore, it is possible to provide a bus duct with excellent electrical characteristics at low cost, and when an annular groove is provided on the holder circumferential surface to ensure creepage distance, assembly is extremely simple. It can be provided at low cost. In addition, if the number of parts in the bus duct is small, transportation costs are reduced accordingly, and even in high-voltage bus ducts, if the conductors are supported only with insulating holders as described above, the structure will be different from that of low-voltage bus ducts. Since they are the same, there are also advantages such as being able to use common jigs.

[Brief explanation of the drawing]

Figure 1 is a cross-sectional view of a high-pressure bus duct according to the present invention, Figures 2 a and b are cross-sectional views and side views of an insulating holder according to the present invention, and Figure 3 is a cross-sectional view of a high-pressure bus duct according to an application example of the present invention. FIG. 4 is a cross-sectional view of a conventional high-pressure bus duct. 1, 5...Housing, 3...Supporting metal fittings, 4,
9...Conductor, 7...Side plate, 7a...Bracket, 8...
...Lid plate, 10...Insulation holder, 10a, 10b
... Annular groove, 11 ... Engagement fitting, 11b ... Extension part.

Claims (1)

[Claims for Utility Model Registration] 1. A plurality of conductors disposed inside the housing along its longitudinal direction, and a plurality of annular grooves supporting both ends of each conductor at predetermined intervals along the longitudinal direction. In a bus duct comprising a cylindrical insulating holder provided with a cylindrical insulating holder, each insulating holder is provided at both ends with engaging fittings that engage with receiving fittings provided on opposing walls of the housing, A bus duct characterized in that the engagement fittings of each of these insulating holders are respectively engaged with the receiving fittings by dropping the insulating holder into the housing. 2. The bus duct according to claim 1, wherein the insulating holder is provided with a plurality of annular grooves for ensuring creepage distance on the circumferential surface of the insulating holder for use in a high-voltage bus duct.