JPH0414911Y2 - - Google Patents

Description

[Detailed description of the invention] Industrial field of application The invention relates to oil-filled electrical equipment equipped with a safety device that utilizes the deformation of the case due to gas generated in the event of an internal failure to cut the conductive part and interrupt the current. It is something.

BACKGROUND ART When an internal failure occurs in a conventional oil-filled electrical device, such as an oil-filled capacitor, the oil decomposes due to heat generation or arcing in the failed part, generating gas and increasing the internal pressure of the case. If left as it was, there was a risk that the case would explode and oil would gush out, leading to a major accident. To prevent this, various safety devices have been proposed for oil-filled capacitors. For example, in a ``safety device configured such that a bridge section provided on an insulating plate breaks and a lead plate placed to bridge the break breaks,'' parallel to the bridge section of the insulating plate during assembly and handling. A reinforcing plate is placed in contact with at least one side of the insulating board (Japanese Utility Model Publication No. 59-78624), or "a weak point is provided in the middle of the insulating board, and the top surface of the board including the top of the weak point is In order to solve the problem that the weak point of a "safety board with a conductive part formed on it" breaks due to an inward force against the security board, an auxiliary board is divided in the middle so that it touches one side of the board. There is a model with a (Utility Model Application Publication No. 58-66626).

Problems that the invention aims to solve: In a safety device that includes an insulating plate and a conductive part arranged to bridge this insulating plate, the safety device can be attached directly or indirectly to the case, for example by hooking a holder attached to the case. In this structure, a play space is provided in this part, and after the safety device is activated, a sufficient distance is obtained between the cutting part of the conductive part by applying a spring plate, etc. (see Utility Model Application No. 58-18027). When multiple conductive parts arranged to bridge the insulating plate are cut as the internal pressure of the case increases, the insulating plate opens on one side, causing a time lag without being cut at the same time, or the conductive parts There were drawbacks such as some parts of the cut may not be cut.

Means for Solving the Problems The present invention seeks to provide oil-filled electrical equipment that eliminates the above-mentioned drawbacks.

That is, a plurality of auxiliary plates are provided in contact with at least one side of an insulating plate supported and fixed to the inner wall of a case of oil-filled electrical equipment, and the auxiliary plates have a comb-like shape in which the shapes are intertwined with each other. This shape prevents the insulating plate from opening on one side due to deformation of the case due to the rise in internal pressure of the case caused by gas generated when an internal failure occurs in oil-filled electrical equipment. This is an oil-filled electrical device that uses a safety device configured so that the conductive parts equally share the internal pressure of the case and disconnect at the same time, interrupting the electrical circuit and preventing an explosion. Note that the smaller the gap between the intertwined parts of the auxiliary plate, the easier it is to cut the plurality of conductive parts at the same time.

Hereinafter, an oil-filled capacitor will be described using the present invention as an example.

Embodiment FIG. 1 is a perspective view of an embodiment of the safety device used in the oil-filled capacitor of the present invention before assembly, and FIG.
In the assembled safety device shown in the figure, A is a plan view and B is a sectional view taken along line A-A' of A.

In FIG. 1, 1 is a bridge portion 1a whose shape is set so as to break at a predetermined pressure approximately at the center;
The insulating plate 2 receives the elongated hole 1b, the notch 1c, and the through holes 1d and 1e. Reference numeral 2 is a support fitting that supports the insulating plate 1 in the case, and is provided with a through hole 2e. 3 is a lead plate made of thin and flat metal that can withstand the allowable current and is easy to break, and has through holes 3d and 3f.
is provided. Reference numeral 4 denotes an L-shaped flat plate made of metal, and teeth are provided on the through hole 4d and the end surface 4a in contact with the lead plate 3 so that the lead plate 3 can be easily cut. 5
is an auxiliary plate provided with a through hole 5e. When the two auxiliary plates 5 are placed facing each other, they have a comb-like shape in which the opposing side surfaces of the long convex portions 5g touch and intertwine with each other. 6 is a crimp fitting such as a rivet that is inserted into the through holes 2e, 1e, 5e and fixes the support fitting 2, the insulating plate 1, and the auxiliary plate 5; 7 is the through hole 1d, 4;
These are crimping fittings such as rivets and eyelets that are inserted into the holes d and 3d to fix the metal L-shaped flat plate 4 and the lead plate 3 to the insulating plate 1.

The through hole 4d of the metal L-shaped flat plate 4 and the through hole 3d of the lead plate 3 are overlapped with the through hole 1d of the insulating plate 1, and the crimping fitting 7 is inserted, and the metal L-shaped flat plate 4 and the lead plate 3 are inserted into the insulating plate 1. Crimp and secure. Then, the through hole 5e of the auxiliary plate 5 of the through hole 1e of the insulating plate 1 is overlapped with the through hole 2e of the support fitting 2 under the through hole 1e, and the crimping fitting 6
are inserted, and the support fitting 2, insulating plate 1, and auxiliary plate 5 are crimped and fixed. The safety device constructed in this manner is shown in FIG. 2, in which A is a plan view thereof and B is a sectional view taken along line A-A' in A.

4 and 5 are cross-sectional views for explaining the oil-immersed capacitor of the present invention equipped with the above-mentioned safety device.
The figure shows a normal case, and FIG. 5 shows a case where the safety device is activated due to an abnormality.

In FIGS. 4 and 5, 8 is a flexible metal case such as a tin plate, 9 is a receiving metal fitting for supporting the supporting metal fitting 2, 10 is a capacitor unit, 1
1 is a drawer lead connecting the capacitor unit 10 and the lead plate 3; 12 is the lead plate 3 and the terminal portion 13;
It is a drawer lead that connects.

In the oil-filled capacitor equipped with the safety device of the present invention shown in FIG. 4, when the internal pressure of the capacitor exceeds the allowable pressure, the side peripheral wall of the case 8 is exposed to stress as it is directed outward as shown in FIG. When it swells after receiving it,
The insulating plate 1, which is supported at both ends by the supporting metal fittings 2 supported and fixed to the inner wall of the case 1 by the receiving metal fittings 9, is pulled in the horizontal direction, and the bridge portion 1a of the insulating plate 1 is broken. When the insulating plate 1 is broken and separated at the bridge portion 1a, the lead plate 3 is cut, or the lead plate 3 is pulled through the L-shaped flat plate 4, and finally the L-shaped plate 3 is pulled.
The lead plate 3 is similarly cut by the tooth-shaped end surface 4a of the shaped flat plate 4.

In this case, since the auxiliary plate 5 is fixed in contact with the insulating plate 1 in parallel to the bridge part 1a, the bridge part 1a
Since the lead plate 3 is reliably pulled in the horizontal direction without warping or breaking, the tensile breaking stress of the bridge portion 1a is instantaneously applied to the lead plate 3 and the lead plate 3 is cut.

Note that the end surface 4a of the L-shaped flat plate 4 may be flat instead of tooth-shaped. Although the lead plate 3 is formed into a thin layered flat plate, the portion in contact with the end surface 4a of the L-shaped flat plate 4 may be formed into a thin layered flat plate shape, and the other portions may have an appropriate shape.
In short, the shape does not matter as long as it can withstand the allowable current of the capacitor and is easy to cut. L
When the tooth-shaped end surface 4a of the shaped flat plate 4 touches the lead plate 3 obliquely, the lead plate 3 is more likely to be cut.

Further, if a laminate of phenolic resin and paper base material is used as the insulating plate 1, and the direction of the fibers is perpendicular to the cross-linking direction of the lead plate 3, it will be advantageous in terms of operation.

Figure 3 shows another embodiment of the safety device used in the oil-filled capacitor of the present invention, in which A is a plan view and B is a B of A.
B′ cross-sectional view.

The difference between FIG. 3 and FIG. 2 is the structure of the auxiliary plate 5, in which the auxiliary plate 5 is provided with two long protrusions 5g, and when the two auxiliary plates 5 are placed facing each other,
It has a comb-shape in which the opposing side surfaces of the long convex portions 5g touch and intertwine with each other, and have the same effect as the security device shown in FIG. 2.

Effects of the invention Since the oil-filled electrical equipment of the invention is configured as described above, arcing does not occur intermittently and the internal electrical circuit is safely and reliably interrupted, thereby avoiding dangers such as explosions and fires. be able to. Furthermore, even if an external force is applied to the insulating plate during assembly, the bridge portion will not be damaged, allowing efficient production. By placing the lead plate at the neutral point of the electrical equipment, the fault current is limited, the insulation distance can be shortened, and the safety device can be made more compact. Furthermore, multiple conductive parts can be disconnected at the same time as the internal pressure of the case increases, so for example, in the case of a three-phase capacitor, single-phase operation can be prevented, and multiple conductive parts of a safety device can be connected in series. When increasing the voltage resistance, multiple conductive parts are cut at the same time, so the series effect can be fully realized, and highly safe oil-filled electrical equipment can be obtained, which has great industrial and practical value. It is something.

[Brief explanation of the drawing]

FIG. 1 is a perspective view of an embodiment of the safety device used in the oil-filled capacitor of the present invention before assembly, and FIG.
The safety device is assembled as shown in the figure, A is the plan view and B is the A of A.
-A' sectional view, Figure 3 is another embodiment of the safety device used in the oil-filled capacitor of the present invention, A is a plan view,
B is a sectional view taken along line B-B' in A, and FIGS. 4 and 5 are explanatory sectional views of the oil-filled capacitor of the present invention equipped with a safety device. This shows the case where the safety device is activated. DESCRIPTION OF SYMBOLS 1...Insulating plate, 1a...Bridge part, 1b...Long hole, 1c...Notch part, 2...Supporting metal fittings, 3...Lead plate (conductive part), 4...L-shaped flat plate, 5... ...Auxiliary plate, 5g...Long protrusion, 8...Case, 9...Bracket, 10...Capacitor unit.

Claims (1)

[Scope of utility model registration request] Due to the increase in internal pressure, the insulating plate fixed to the inner wall of the case is pulled, and when a predetermined pressure is reached, the bridge section provided on the insulating plate breaks, and the conductive section arranged to bridge this breaks. In the oil-filled electrical equipment equipped with the safety device configured, a comb-shaped auxiliary plate is provided parallel to the bridge portion and in contact with at least one side of the insulating plate, and in such a manner that the long convex portions facing each other touch and intertwine. Oil-filled electrical equipment characterized by having multiple sheets arranged.