JPH0517859Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Purpose of the Invention] (Field of Industrial Application) The present invention relates to a terminal switching device for a transformer, particularly a dry type transformer.

(Prior Art) The secondary terminal switching system of a conventional dry type transformer will be explained with reference to the single line diagram in FIG.

As shown in the figure, transformers 1 and 2 of the same capacity are connected in parallel, and transformers 1 and 2 are connected in parallel.
Loads 3 and 4 and loads 5 and 6 are connected to them, respectively. A switching device 7 or 8 is provided between the transformer 1 or 2 and the loads 3 and 4 or loads 5 and 6, respectively, and a circuit breaker 9 or 10 is provided on the power receiving side of the transformer 1 or 2. Normally, two transformers 1 and 2 are operated in parallel, but if a problem occurs with transformer 1, for example, the circuit breaker 9 is opened and the switching device 7 is removed to disconnect the load side circuit, and the transformer The load side terminals of the transformer 1 and the load side terminals of the transformer 1 are connected by cables 11 and 12 as shown by broken lines, and the transformer 2 is configured to supply power to all the loads 3 to 6.

The structure of this load-side switching device 7 or 8 is, for example, as shown in FIG. That is, the secondary side lead wire 14 led out from the coil of the transformer main body is connected to the upper surface of the L-shaped terminal connection lever 13, and the switching piece 15 is connected to the vertical surface of this terminal connection bar 13. Connect. This switching piece 1
5, an external terminal connecting bar 16 is connected to the external terminal connecting bar 16, an external cable 17 is connected to the external terminal connecting bar 16, and the external cable 17 is fixed with a cable bracket 18.

(Problems to be Solved by the Invention) However, the conventional dry transformer having the above structure has the following drawbacks.

The lead-in length (dimension b) of the external cable 17, that is, the length from the position of the cable bracket 18 to the terminal, is determined by the cable size and cannot be made extremely small. Further, the height of the cable bracket 18 from the floor (dimension c) is determined by the bending curvature R of the cable 17, and this dimension cannot be made extremely small. In contrast, the total height of the switching piece 15 mounting part (dimension a)
The contact surfaces between the terminal connection bar 13 and the external terminal connection bar 16 and the switching piece 15 are arranged along the height direction, and the total height (h dimension) of this part from the floor Since it occupies a large proportion, it was not possible to downsize it.

For example, in the case of a single-phase three-wire system, the switching piece 15
At least 6 terminal portions having . When switching these terminals, it is necessary to prevent the bolt head on the back side of the L-shaped terminal connection bar 13 from rotating, which is difficult and inefficient. Moreover, if two bolts are used at one location to connect the switching piece 15, eight bolts will be used for each terminal of one phase, which increases the switching time in the event of an emergency trouble.

The present invention has been devised to eliminate the above-mentioned drawbacks, and its purpose is to provide a transformer switching device that is small in size and has good switching workability.

[Structure of the invention] (Means and effects for solving the problem) In order to achieve the above object, the present invention provides a switching method for a transformer configured to separate the secondary terminal of the transformer from the main body of the transformer. In the device, horizontally align the connection surfaces of the switching valve pieces of the secondary side terminal connection bar that connects the secondary side outlet wire led out from the coil of the transformer body and the external terminal connection bar that connects external cables, etc. The two terminal connecting bars are arranged to face each other along the direction, a switching piece is inserted between the opposing faces, and the two terminal connecting bars are fastened together with bolts and nuts. It is.

As described above, in the transformer switching device according to the present invention, the contact portions of each terminal connection bar and the switching piece are lined up horizontally, so the height dimension can be reduced, and the Since the nuts can be tightened and removed, and the number of bolts is reduced, bolts and nuts can be easily attached and removed.

(Example) Embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view of an embodiment of the present invention, and FIG. 2 is a side view of the entire transformer using the switching device of the present invention. Note that the same parts as those of the conventional example already explained will be described with the same reference numerals.

In these figures, the transformer body 23 is connected to the iron core 2
A coil 25 is wound around the transformer container 2.
It is housed in 6. A secondary side lead wire 14 led out from the coil of the transformer main body is connected to a terminal connection bar 19 that is upwardly L-shaped. An external cable 17 is connected to the external terminal connection bar 21 . The terminal connection bar 19 and the external terminal connection bar 21 are arranged so that their switching piece contact surfaces face each other along the horizontal direction, and the switching piece 2 is placed between them.
0 are arranged and these are collectively tightened and fixed with bolts and nuts 22. Note that 27 is a protective case.

Since this embodiment is configured as described above,
By attaching and detaching each terminal connecting bar 19, 21 and switching piece 20 using bolts and nuts 22, each terminal connecting bar 19, 21 and switching piece 20 can be connected and disconnected.

Therefore, the present embodiment has the following advantages. Since the connection parts of the secondary terminal connection bar 19 and the external terminal connection bar 21 and the switching piece 20 are at the same height, only one contact part is required, and the height of the switching device is reduced. In addition, since the secondary terminal connection bar 19 and the external terminal connection bar 21 are fastened together in this embodiment, the number of bolts and nuts 22 required is half that of the conventional fastening structure. Moreover, the switching operation can be performed from the top of the protective case 27 above the switching device, and the bolts and nuts 22 are located outside the terminal connection bars 19 and 21, so that the bolts can be easily fastened or removed.

Furthermore, in this embodiment, the current in the switching piece 20 flows in the thickness direction of the switching piece 20, so the current density is low and the amount of heat generated is small, so the size of the switching piece 20 can be made small.

Note that the present invention is not limited to the shape of the above-mentioned embodiments; for example, the shape of each terminal connection bar may be changed depending on the support insulator of the bar or other parts, etc., and the present invention will not be considered. It is not different from the effect of example. However, if the secondary side terminal connecting bar is shaped into a downward L-shape, there is a problem that the workability of tightening or removing the tightening bolt becomes poor.

[Effects of the invention] As explained above, the invention provides the following effects.

(1) The height of the switching device becomes smaller, reducing the overall height of the transformer.

(2) It becomes easier to tighten and remove the tightening bolts of the switching device, and the switching time is shortened.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the present invention, and FIG. 2 is a side view of the entire transformer using the switching device of the present invention.
FIG. 3 is a perspective view of a conventional switching device, and FIG. 4 is a single line diagram in which a transformer equipped with the switching device is incorporated. 14...Secondary side outlet wire, 17...External cable, 19...Terminal connection bar, 20...Switching piece,
21...External terminal connection bar, 22...Volt,
Natsuto, 23...The main body of the transformer. 24... Iron core, 2
5... Coil, 26... Transformer container.

Claims (1)

[Scope of utility model registration request] In a transformer switching device configured to separate the secondary side terminal led out from the coil of the transformer main body and the external terminal such as an external cable, the secondary side lead wire led out from the coil of the transformer main body. The switching piece connecting surfaces of the terminal connecting bar that connects the terminal and the external terminal connecting bar that connects the external cable etc. are horizontally opposed, and the switching piece is inserted between the opposing surfaces to connect the two A switching device for a transformer, characterized in that it is configured to be tightened together with a terminal connection bar together with bolts and nuts.