JPH0430752Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention relates to the improvement of open cutouts.
This relates to a structure devised to provide load switching performance by attaching a semiconductor-type arc extinguishing device to an existing open cutout that does not have an arc extinguishing device. In the case where the current flowing between the upper contact and the same electrode is commutated to the thyristor side after the upper contact is opened, a configuration is proposed in which this commutation circuit is reliably formed even after the upper contact is opened. It is something.

(Prior Art) Open cutouts are used in high voltage or extra high voltage distribution lines to protect the primary side of transformers. Most of the open cutouts used in this case were not equipped with an arc extinguisher for switching the load.

(Problem that the invention aims to solve) Therefore, when opening the electrical circuit, it is necessary to first put the electrical circuit in a no-voltage state using a disconnector, and then open it.
Alternatively, there were many inconveniences in load switching operations, such as cutting the fuse attached to the fuse tube and forcibly opening the electrical circuit.

In addition, in order to solve the above problems, some devices are equipped with an arc extinguishing device consisting of a narrow arc extinguishing chamber and a quick cutting mechanism, but this arc extinguishing device has a complicated structure and is large. There were other problems.

Furthermore, it is also possible to connect a semiconductor-type arc extinguishing device that utilizes the characteristics of semiconductor elements such as thyristors and diodes in parallel to the main contact (wire break), but in such a case, the commutation to the thyristor If the circuit is not formed reliably, there are problems such as failure of commutation and failure to open/close or shut off.

(Means for Solving the Problems) This proposal is intended to solve the various problems mentioned above, and consists of a main body 1 having an upper fixed electrode 2 on the upper part and a lower fixed electrode 9 on the lower part, and upper and lower contacts. 1
A fuse 21 is connected between 8 and 19, and its upper contact 18 is brought into contact with the upper fixed electrode 2, and its lower lower contact 19 is brought into contact with the lower fixed electrode 9. a fuse tube 17 that is removable from the main body 1 such that the upper contact 18 is separated from the upper fixed electrode 2 around the hinge engagement portion of the fixed contact 19 to open the electric circuit; , the upper fixed electrode 2
The main body consists of an anti-parallel connection of thyristors connected in parallel to the fixed electrode 2 and the contact 18, which commutates the current flowing between the upper contact 18 and extinguishes the arc generated between the electrode 2 and the contact 18. 2
4, the main body 24 has one end fixedly connected to the fixed electrode 2, and an auxiliary contact piece 26 of an elastic member connected to the other end of the main body 24 is connected to the above of the fuse tube 17. Top surface 28a of cap screw 28 screwed onto contact 18
When the tip 26a side of the contact piece 26 is separated from the upper fixed electrode 2, the contact piece 26 contacts the cap screw 28 with a delay in the separation of the upper contact 18. top surface 2
The present invention proposes an open cutout characterized in that it is formed to extend in the direction of opening of the fuse tube 17 so as to be separated from the fuse tube 8a.

(Example) An example of the present invention will be specifically described below. Since the open cutout of the present invention is not particularly different from the existing one except for the main body of the arc extinguishing device, the structure will be briefly explained based on FIG. 4.

1 is a porcelain body formed in a cylindrical shape,
A plurality of hats 1a are provided extending from the upper part to the lower part. 2 is an upper fixed electrode located on the upper part of the main body 1 and fixed by a U-shaped band 3, a U-shaped auxiliary mounting bracket 4, and a nut 5; , a mounting support 6 that also serves as a stopper, an L-shaped guide fitting 8 riveted to the top side of the mounting support 6 with rivets 7, and a power supply side electric wire connection terminal 9 attached to the vertical portion 8a of the guide fitting. The electrode 2 made of a spring member such as a phosphor bronze plate is located on the lower surface 8c side of the guide fitting 8 and is integrally riveted thereto.

A lower fixed electrode 9 is located at the lower part of the main body 1 and is fixed by a mounting band 10, a U-shaped auxiliary fitting 11, and a nut (not particularly shown). On the outside, a mounting support 12 that also serves as a cover and a load-side wire connection terminal 13 provided at the lower end of the support 12 bent into a crank shape are provided, and the electrode 9 made of a phosphor bronze plate is attached to the support 12. It is riveted along the inner surface 12b of.

Reference numeral 14 denotes a main body support fitting for attaching a cutout, which is located at the center of the main body 1 and is tightened and fixed by a U-shaped band 15 and a nut 16, to an arm of a utility pole.

Reference numeral 17 is a release type in which an upper contact 18 and a lower contact 19, which are capable of contacting or separating from the upper fixed electrode 2 and lower fixed electrode 9 on the main body 1 side, are fixed to the upper and lower parts of the insulating cylinder 20, respectively. One of the upper contacts 18, which is a fuse cylinder and is fixed to the insulating cylinder 20, has a stopper part 18a protruding forward (to the fixed electrode side), a contact part 18b, and a switch hook part 18C provided at the rear. , the cap screw 28 screwed onto the upper end, and the mounting portion 1
8d, and its mounting part 18d is
It is fixed to the outer periphery of the upper end of the insulating cylinder 20 made of FRP by adhesive and screws. In addition, the insulation cylinder 20
The other lower contact 19 fixed to the outer periphery of the lower end has a mounting part 19a, a contact part 19c pivotally attached to the mounting part 19a by a shaft 19b so as to be freely openable, and an engaging protrusion provided at the rear of the contact part 19c. 19d and a fuse lead tightening part 19e. Note that the fuse tube 17 is connected to the above-mentioned engaging protrusion 19.
d is rotatably hinged to a notch-shaped engagement hole 12c formed in the mounting support base 12 on the main body 1 side, and the fuse tube 17 is in the open state, that is, centered around the hinge engagement part. When the upper contact 18 is at the lower side, pull the opening/closing hook 18c provided on the upper contact 3 side onto an operating rod (not shown) and push it upward to open the fuse cylinder 1.
7 rotates counterclockwise around the hinge engagement portion between the engagement protrusion 19d and the engagement hole 12c, the upper contact 3 contacts the upper fixed electrode 2 on the main body 1 side, and the lower contact 19 contacts the upper fixed electrode 2 on the main body 1 side. The fuse tubes 17 are held in the closed (closed) state as shown in FIG. 4 by contacting the fixed electrodes 9 on the first side.

Reference numeral 21 denotes a fuse loaded in the fuse tube 17, which connects the upper contact 18 and the lower contact 19, and one end (not particularly shown) is connected to the cap screw 2.
The fuse lead 21a at the other end connected to the insulating tube 8 and led out from the lower end of the insulating tube 20 is connected to the fuse lead tightening portion 19e of the lower contact 19. Next, an embodiment will be described in which the main body 24 of the arc extinguishing device, the current transformer 29, and the trigger circuit 30 are attached to the open cutout having the above structure. 1st
In the case of the figure, the main body 24 consisting of anti-parallel connection of thyristors is attached to the main body 1 side, and the main body 24 is as shown in the circuit diagram of Fig. 2.
It has a structure in which high-voltage thyristors 22a and 22b are connected in reverse parallel and housed in a sealed insulating case 23, and one of the main bodies 24 is electrically connected to the upper fixed electrode 2 via a terminal 25 that also serves as a mounting bracket. The other side of the main body 24 is connected to the upper surface 8b of the guide fitting 8 which is connected to the fuse tube 1 via an auxiliary contact piece 26 made of an elastic member such as a phosphor bronze plate.
The upper surface 28a of the cap screw 28, which is electrically connected to the upper contact 18 on the 7 side, is in elastic pressure contact from above. In other words, the main body 24 has the thyristors 22a and 22b connected in antiparallel as described above.
is the upper fixed electrode 2 and fuse tube 17 on the main body 1 side.
It is connected in parallel to the upper contact 18 on the side. The above-mentioned auxiliary contact piece 26 is shown in FIG. 1 in order to continue for a while even after the upper contact point 18 of the fuse tube 17 is separated from the upper fixed electrode 2 on the main body 1 side to form a commutation circuit to the thyristor. Like that tip 2
The 6a side is formed to extend in the opening direction of the fuse tube 17, that is, in the opening direction of the upper contact 18. A current transformer 29 is used to detect the current flowing between the upper fixed electrode 2 and the upper contact 18. The through-type current transformer 29 is inserted into the guide fitting 8 so as to pass through the upper fixed electrode 2. The signal detected by the current transformer 29 is input to a trigger circuit 30 housed in a sealed case, and the output signal from the circuit is used to trigger the thyristor 22 of the main body 24.
a and 22b are designed to fire. The sealed case of the trigger circuit 30 is attached to the upper surface 8b of the guide fitting 8. In this case, the trigger circuit 30 is driven not only by a dry battery but also by a rechargeable battery such as a solar battery.

The following operation will be explained regarding the open cutout having the above configuration.

The state shown in FIG. 1 shows the closed (circuit) state, and normally a current flows between the upper fixed electrode 2 on the main body 1 side and the upper contact 18 on the fuse cylinder side.
An ignition signal is constantly applied to the gate 27 of the thyristor by the current transformer 29 and the trigger circuit 30.

In this state (state A in Fig. 3), when the opening/closing hook portion 18c is hooked onto the hook portion of the operating rod and pulled diagonally downward to open the electric circuit, the fuse tube 17 is connected to the lower fixed electrode. 9 and the hinge engagement portion of the lower contact 19, the contact portion 18b of the upper contact 18 of the fuse tube 17 is separated from the upper fixed electrode 2 on the main body 1 side, and an arc is created between the two. Occur. The generated arc is connected to the fixed electrode 2.
Even after the contact point 3 is separated, the tip 26a of the auxiliary contact piece 26 of the main body 24 is still attached to the cap screw 28.
Since it is in contact with the upper surface 28a, a commutation circuit to the thyristor 22a or 22b is formed.
The above arc voltage will be applied to the thyristor. When the arc voltage reaches the minimum operating voltage, one of the thyristors with matching polarity is immediately turned on, and the upper fixed electrode 2 - guide metal fitting 8
Current flows through the commutation circuit of - terminal 25 - thyristor 22a or 22b - auxiliary contact piece 26 - cap screw 28 - upper contact 18 (state in FIG. 3B).

In other words, when an arc voltage is generated, an arc current flows between the upper fixed electrode 2 and the upper contact 18, and therefore the current transformer 29 detects this current, and an arcing signal is continuously applied to the gate 27 via the trigger circuit 30, so that the thyristor immediately turns on when the arc voltage reaches the minimum operating voltage of the thyristor as described above.

As a result, the upper fixed electrode 2 on the main body 1 side and the upper contact 18 of the fuse tube 17 become non-voltage, and the arc is extinguished. and the phase of the power supply is 0° or 180°
Then, the thyristor 22a or 22b is turned off. In this state, the fuse tube 17 is further rotated, so that the auxiliary contact piece 26 is attached to the cap screw 28.
However, at that time there is no voltage, and even if the auxiliary contact piece 26 separates from the cap screw 28, no arc will occur between them. (Status shown in Figure 3 C).

On the other hand, when the fuse tube 17 is turned on to close the electric circuit, when the fuse tube 17 rotates counterclockwise, the cap screw 28 of the fuse tube 17 first pushes up the auxiliary contact piece 26. and comes into contact with the same contact piece 26. In this case, the thyristors 22a and 22b are off and are therefore non-conductive. Eventually, when the contact portion 18b of the upper contact on the fuse cylinder 17 side comes very close to the upper fixed electrode 2 on the main body 1 side, an arc of advance discharge is generated between the two. Due to the generation of this arc voltage, a current flows through the upper fixed electrode 2 and the upper contact 18, this current is detected by the current transformer 29, and is further passed through the trigger circuit 30 to the gates 27 of the thyristors 22a and 22b. On the other hand, it continues to be given as an ignition signal.

At the same time, the arc voltage is applied to the thyristor and when it reaches the minimum operating voltage, the thyristor 22
a and 22b are immediately turned on and current commutates to thyristor 22a or 22b.

When the contact part 18b moves further and completely contacts the upper fixed electrode 2, the voltage between the electrodes, that is, the thyristor 2
The voltage applied across terminals 2a and 22b becomes 0, turning off the thyristor, and the current flowing through the thyristor becomes less than the holding current, turning the thyristor off. In this state, the current returns to the normal state in which it flows through the main circuit composed of the upper fixed electrode 2 and the upper contact 18.

(Effects of the invention) As described above, the present invention has a main body 1 having an upper fixed electrode 2 at the upper part and a lower fixed electrode 9 at the lower part.
A fuse 21 is connected between the upper and lower contacts 18 and 19, and the upper contact 18 is brought into contact with the upper fixed electrode 2, and the lower contact 19 is brought into contact with the lower fixed electrode 9, and the fuse 21 is opened. At times, the upper contact 18 is separated from the upper fixed electrode 2 around the hinge engagement portion between the lower fixed electrode 9 and the fixed contact 19, so that the electric circuit is opened. And, when the above is released,
A reverse thyristor connected in parallel to the fixed electrode 2 and the contact 18, which commutates the current flowing between the upper fixed electrode 2 and the upper contact 18 to extinguish the arc generated between the electrode 2 and the contact 18. In an arc extinguishing device comprising a main body 24 connected in parallel, the main body 24 has one end fixedly connected to the fixed electrode 2, and an auxiliary contact piece 26 of an elastic member connected to the other end of the main body 24. The upper surface 28a of the cap screw 28 screwed onto the contact 18 of the fuse cylinder 17 is pressed from above into contact with the upper surface 28a, and the tip 26a of the contact piece 26 is further pressed against the upper surface 28a when the upper contact 18 is separated from the upper fixed electrode 2. As a result of forming the contact piece 26 to extend in the opening direction of the fuse tube 17 in order to separate from the upper surface 28a of the cap screw 28 after the opening of the contact 18, the upper contact of the fuse tube opens from the upper fixed electrode on the main body side. Even when an arc is about to occur between the upper fixed electrode 2 on the main body 1 side and the upper contact 18 on the fuse cylinder 17 side when the arc is released, that is, when the load is switched on and off, the thyristor interposed in advance as described above prevents the arc from occurring. Electrical conduction occurs due to the arc voltage, and there is no voltage between the upper fixed electrode and the upper contact, and the arc is immediately extinguished, so the circuit can be opened safely in a voltage-free and arc-free state.

In addition, as mentioned above, the upper fixed electrode 2 on the main body 1 side
The main body 24, which consists of a thyristor connected in parallel to the upper contact 18 of the fuse tube 17, is small and lightweight, so even if these are installed in an existing open cutout, the cutout will not become particularly large or heavy. do not have.

Further, when the upper contact 18 is separated from the upper fixed electrode 2, the auxiliary contact piece 26 of the elastic member
The upper surface 28a of the cap screw 28 of No. 8 is elastically pressed into contact with the upper surface 28a of the cap screw 28 from above, and the same contact piece 2
Since the tip 26a side of the contact piece 6 is extended in the opening direction of the fuse tube 17, even after the fixed contact 18 separates from the fixed electrode 2, a commutation circuit to the thyristor is reliably formed by the contact piece 28. As a result,
The extinction of the arc by the same thyristor is ensured.
It has the following features and is extremely practical.

[Brief explanation of drawings]

1 to 3 show embodiments of the present invention. FIG. 1 is a front view showing the main parts of the open cutout of the present invention, FIG. 2 is a schematic circuit diagram of the arc extinguishing device, and FIG. The figure is an explanatory diagram of the operating situation, and FIG. 4 is a front view of a conventional open cutout. DESCRIPTION OF SYMBOLS 1... Main body, 2... Upper fixed electrode, 9... Lower fixed electrode, 17... Fuse tube, 18... Upper contact, 19... Lower contact, 20... Insulating tube, 22
a, 22b...thyristor, 24...subject, 25
... terminal, 26 ... auxiliary contact, 2, 26a ... tip, 7 ... gate, 29 ... current transformer, 30 ... trigger circuit.

Claims (1)

[Scope of utility model registration request] A main body 1 provided with an upper fixed electrode 2 on the upper part and a lower fixed electrode 9 on the lower part, and upper and lower contacts 1.
A fuse 21 is connected between the fuses 8 and 19, and the upper contact 18 above the fuse 21 is brought into contact with the upper fixed electrode 2, and the lower lower contact 19 is brought into contact with the lower fixed electrode 9. a fuse tube 17 that is removable from the main body 1 such that the upper contact 18 is separated from the upper fixed electrode 2 around the hinge engagement portion of the fixed contact 19 to open the electric circuit; , the upper fixed electrode 2
The main body consists of an anti-parallel connection of thyristors connected in parallel to the fixed electrode 2 and the contact 18, which commutates the current flowing between the upper contact 18 and extinguishes the arc generated between the electrode 2 and the contact 18. 2
4, the main body 24 has one end fixedly connected to the fixed electrode 2, and an auxiliary contact piece 26 of an elastic member connected to the other end of the main body 24 is connected to the upper part of the fuse cylinder 17. Top surface 28a of cap screw 28 screwed onto contact 18
When the tip 26a side of the contact piece 26 is separated from the upper fixed electrode 2, the contact piece 26 contacts the cap screw 28 with a delay in the separation of the upper contact 18. top surface 2
The open cutout is characterized in that it is formed to extend in the direction of opening of the fuse tube 17 so as to be separated from the fuse tube 8a.