JPH0445925B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an arc extinguishing device for circuits and breakers.

[Prior art] Conventionally, a yoke is provided at the contact part, a conductor is wound around the yoke, and a short circuit current is passed through the coil part.
A method was proposed in which the arc was driven by the magnetic flux generated by this current (for example, in 1983-
115060).

[Problem to be solved by the invention]

However, in high-capacity circuits and disconnectors of 400 A or more, the wire cross-sectional area of the coil section becomes large, making it difficult to wind the coil, and if the coil section is a lead wire, it is not fixed, so The disadvantage is that the coil itself vibrates when current is applied, reducing the magnetic driving force of the arc and impairing the interrupting performance.

On the other hand, there was a device in which a pair of current wire rings were provided on both sides of the contact part so that the axial direction of the arch-shaped current wire ring crossed the opening direction of the contact part (for example, Utility Model No. 51-018963 However, since 1/2 of the current is shunted into each current wire ring, the number of turns is actually 1, so the generated magnetic flux is small, and the leakage of magnetic flux linked to the arc is large, so the arc driving force is The drawback was that it was small. Furthermore, since the current wire ring extends to the open position of the movable contact, it is necessary to increase the insulation interval between the current wire ring and the movable contact, which has the disadvantage of increasing the size of the case.

Therefore, an object of the present invention is to provide an arc extinguishing device that is easy to assemble and can increase arc driving force without increasing the size of the case.

[Means to solve the problem]

The arc extinguishing device of this invention has a U-shaped yoke 16.
, the main fixed contact 14 whose tip 14a has entered the inside of the yoke 16, and the main fixed contact 14, which has a substantially helical planar shape and whose winding portion is connected to the side columns 16a and 16b of the yoke 16.
The main fixed contact 14 is wound in such a way that the current flowing through the part that is wound around at least one of the yoke 16 and overlaps the main fixed contact 14 is in the same direction as the main fixed contact 14. Tip 1
A flat spiral plate 18 with one end 19 connected to 4a
The fixed contact 21 is connected to the other end 22 of the spiral plate 18 and the current flowing through the part passing inside the yoke 16 is in the same direction as the main fixed contact 14.
, a fixed contact 23 provided inside the yoke 16 of this fixed contact 21, and this fixed contact 23.
a movable contact 8 having a movable contact 29 that separates from the
28.

[Effect]

According to the configuration of the present invention, since the main fixed contact, the spiral plate, and the fixed contact pass inside the yoke, the number of interlinked magnetic fluxes when an arc is generated can be increased, and therefore the arc driving force can be increased. Moreover, since the spiral lathe can be wound multiple times, it is possible to further increase the arc driving force. In addition, since the lathe is fitted onto the side column and both ends are connected to the main fixed contact and the fixed contact, the conventional winding work is not required, making the structure simple and easy to assemble. By setting the thickness, vibration can also be suppressed compared to conventional methods. Furthermore, since the spiral plate is wound around the side pillars of the yoke, it is closer to the arc driving point than when the coil part is provided in the center of the U-shaped yoke.Therefore, there is less leakage magnetic flux, so the arc driving point Therefore, the arc driving force can be increased. Moreover, since the lathe does not extend to the open position of the movable contact, the case does not become large.

〔Example〕

A circuit breaker to which an embodiment of the present invention is applied will be explained based on FIGS. 1 to 4. That is, 1 is a stand, 2 is a cover, and these form the main body of the cutter. 3 is the power supply side terminal,
4 is a load side terminal, 5 is a contact section, 6 is an arc extinguishing device including the contact section 5, 7 is an overcurrent operating element, 8 is a main movable contact with a reversing mechanism, 9 is a handle, and 10 is an opening/closing/trip switch. It is a link mechanism for

The arc extinguishing device 6 is connected to the grid 1 facing the contact portion 5.
1 is arranged, and an exhaust plate 12 is provided on the rear surface of the grid 11.
has. The contact portion 5 is connected to the terminal plate 1 of the power supply side terminal 3.
The end of the main fixed contact 14 is welded to the end of the main fixed contact 14 and is arranged above the terminal plate 13, and U-shaped yokes 15 and 16 are arranged between the terminal plate 13 and the main fixed contact 14. A main fixed contact 14 passes through each inner side of the main fixed contact 14 corresponding to the position of the yoke 15.
A main fixed contact 17 is fixedly installed at 4. Further, as shown in FIGS. 3 and 4, the S-shaped plate 18 forming a spiral plate is loosely fitted into the side columns 16a, 16b of the yoke 16, and one end 19 thereof, which forms a bent step, is connected to the yoke 16.
The fixed contact 21 is welded to the bent tip 14a of the main fixed contact 14 passing through the inside of the yoke 16, and is integrated with the arc travel plate 20 formed of a T-shaped flat plate, to the S-shaped plate 18 inside the yoke 16. They are loosely fitted so as to overlap, one end of which is welded to the other end 22 which is a bent step of the S-shaped plate 18, and an auxiliary fixed contact 23 is individually provided at a position inside the yoke 16 of this fixed contact 21. , a grid 11 is placed on the tip of the arc running plate 20. In this way, the main fixed contact 14, the S-shaped plate 18, and the arc travel plate 20 or the fixed contact 21 pass inside the yoke 16. The yokes 15 and 16 are made of laminated thin plates.
These are fixed to the yoke holding plate 24 with pins 25 and covered with an insulating plate 26 to insulate the terminal plate 13 and the main fixed contact 14. The movable contact 8 has a main movable contact 2 facing the main fixed contact 17 at its tip.
7, and an auxiliary movable contact 28 is pivotally attached to the tip, and an auxiliary movable contact 29 is provided thereto facing the auxiliary fixed contact 23, and the auxiliary movable contact 29 is fixed with a torsion coil spring (not shown). It is biased to rotate toward the contact 23 side.

FIG. 1 shows the on state, and the terminal board 13 and the main fixed contact 1 are connected between the power supply side terminal 3 and the load side terminal 4.
4, the main fixed contact 17, the main movable contact 27, the movable contact 8, the braided wire 30, and the overcurrent operation element 7 are connected to each other by an electric circuit, and electricity is applied to this. Note that when the movable contact 8 is turned on, the movable contact 29 of the auxiliary movable contact 28 first contacts the auxiliary fixed contact 23, and then the main movable contact 27 contacts the main fixed contact 17.

The off state is when the handle 9 is tilted to the right (clockwise) in FIG. At this time, the center line of the tension spring 31 of the link mechanism 10 crosses the tripping plate connecting shaft 32 to the right, the link connecting shaft 33 is pulled upward, the arm 34 rotates, and the movable contact 8 performs the opening operation. do.

A trip state occurs when an overcurrent flows through the electrical circuit. In this case, the armature 35 is attracted to the magnetic arm 34 by the magnetic flux created by the braided wire 30, and when the contact pressure spring 36 crosses the reversal axis 37, the movable contact 8 is reversed and opened. At the same time, overcurrent operating element 7
operates to operate the latch fitting 38, and the trip plate 3
9 is released and the linkage mechanism 10 becomes unbalanced.
As a result, the arm 34 is connected via the links 40 and 41.
rotates, the main movable contact 8 performs an opening operation, and the handle 9 becomes neutral and enters a trip state.

With these opening operations, the main movable contact 27 first separates from the main fixed contact 17, and then the auxiliary movable contact 29 separates from the auxiliary fixed point 23. Therefore, the short-circuit current at the time of opening flows through the auxiliary movable contact 29, and a main arc is generated between the auxiliary movable contact 29 and the auxiliary fixed contact 23. At this time, the short circuit current flows through the main fixed contact 14, the S-shaped plate 18, the fixed contact 21, and the arc travel plate 20, so it interlinks with the yoke 16 three times, and the side columns 16a, 1 of the yoke 16
A magnetic field is generated between the ends of 6b. This magnetic field drives the arc toward grid 11, and
1, it is cooled and the arc is extinguished. A slight arc is also generated when the main movable contact 27 is opened, but this is also driven toward the grid 11 by the magnetic field generated by the yoke 15.

With this configuration, the main fixed contact 14,
S-shaped plate 18 which is a spiral plate and fixed contactor 21
passes inside the yoke 16, it is possible to increase the number of interlinked magnetic fluxes when an arc is generated, thereby increasing the arc driving force.Moreover, since the S-shaped plate 18 can be wound multiple times, the arc can be further improved. It is possible to increase the driving force.

In addition, the S-shaped plate 18 is fitted onto the side columns 16a and 16b, and both ends are connected to the main fixed contact 14 and the fixed contact 21.
Since the conventional winding work is not required, the structure is simple and easy to assemble.
By setting the thickness of the S-shaped plate 18, vibration can also be suppressed compared to the conventional case.

Furthermore, since the S-shaped plate 18 is wound around the side columns 16a and 16b of the yoke 16 as shown in FIG. 5a, a coil portion C is provided at the center of the U-shaped yoke 16 as shown in FIG. 5b. It is closer to the arc driving point A than the yoke, so even if the yoke is energized to magnetic saturation, there is less magnetic flux leaking to the arc driving point A, so the magnetic flux density at the arc driving point can be increased. Arc driving force can be increased.

Moreover, since the S-shaped plate 18 does not extend to the open position of the movable contact 29, the case does not become large.

Incidentally, the spiral plate of the present invention can be formed by stacking a plurality of S-shaped plates and joining them to each other to substantially form a plurality of turns. Further, the spiral plate can be formed by a combination of a U-shaped plate and a rectangular plate, or may be formed by a combination of a plurality of flat plates regardless of shape. Furthermore, in this invention, including the case where there is no auxiliary movable contact 28, the yoke 16, the S-shaped plate 18, the auxiliary fixed contact 23, etc. are replaced with the main fixed contact 17 and the yoke 15, and the main movable contact 27 is directly connected. It may also be provided against the

〔Effect of the invention〕

According to the arc extinguishing device of this invention, the main fixed contact;
Since the spiral plate and the fixed contact pass inside the yoke, the number of interlinked magnetic fluxes when an arc is generated can be increased, thus increasing the arc driving force, and the lathe plate can be wound multiple times. Therefore, it is possible to further increase the arc driving force. In addition, since the spiral plate is fitted onto the side column and both ends are connected to the main fixed contact and the fixed contact, the conventional winding work is not required, making the structure simple and easy to assemble. By setting the plate thickness, vibration can also be suppressed compared to conventional methods. Furthermore, since the spiral plate is wound around the side pillars of the yoke, it is closer to the arc driving point than when the coil part is provided in the center of the U-shaped yoke.Therefore, there is less leakage magnetic flux, so the arc driving point Therefore, the arc driving force can be increased. Moreover, since the lathe does not extend to the open position of the movable contact, there is an effect that the case does not become large.

[Brief explanation of drawings]

Fig. 1 is a cross-sectional view of a circuit board or stage device to which an embodiment of the present invention is applied, Fig. 2 is a partial side view of the arc extinguishing device with the auxiliary movable contact removed, and Fig. 3 is its side view. A plan view, FIG. 4 is an exploded perspective view of the main fixed contact, the spiral plate and the fixed contact, and FIG. 5 is an explanatory diagram of the yoke portion. 8, 28...Movable contact, 14...Main fixed contact, 14a...Tip, 16...Yoke, 16a,
16b... Side pillar, 18... S-shaped plate which is a spiral plate, 19... One end, 21... Fixed contact, 22...
...Other end, 23... Fixed contact, 29... Movable contact.

Claims (1)

[Claims] 1. A U-shaped yoke 16, a main fixed contact 14 whose tip 14a enters inside the yoke 16,
It has a substantially helical shape in plan view, and its winding portion is connected to the yoke 1.
The electric current is wound around at least one of the side columns 16a and 16b of No. 6 and flows through a portion inside the yoke 16 that overlaps with the main fixed contact 14, so that the current flows in the same direction as the main fixed contact 14. A current flows through a flat spiral plate 18 whose one end 19 is connected to the tip 14a of the main fixed contact 14, and through a portion connected to the other end 22 of this spiral plate 18 and passing inside the yoke 16. A fixed contact 21 which is in the same direction as the main fixed contact 14, and this fixed contact 21.
A fixed contact 2 provided inside the yoke 16 of
3, and a movable contact 29 that separates from this fixed contact 23.
An arc extinguishing device equipped with movable contacts 8 and 28. 2. The arc extinguishing device according to claim 1, wherein the spiral plate 18 is an S-shaped plate wound around the pair of side columns 16a, 16b of the yoke 16.