JP2965331B2 - Circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the present invention pertains] In the present invention, when a short circuit occurs, only a movable conductor is rotated by an electromagnetic repulsion force to open a contact at a high speed without waiting for an opening operation by an opening / closing mechanism. The present invention relates to an improvement of an insulator mounted on a movable conductor for the purpose of improving current limiting performance and insulating performance of a circuit breaker of a type that performs extreme breaking and preventing damage to a mechanism.

[Conventional technology]

Conventional circuit breakers guide the arc generated between the contacts due to the effect of the magnetic field from the arc extinguishing device, arc runner, parallel conductor, etc., to the arc extinguishing device, and extinguish the arc. It has a great effect on driving the arc,
When the short-circuit current increases, a large amount of arc gas is explosively generated, and the gas flows to the mechanism side opposite to the arc extinguishing device, and the gas flow causes the arc to be drawn back to the mechanism side and is driven by the above-described magnetic field effect. There was a problem of halving power.

As a countermeasure, a method has been devised in which the flow of the arc gas is restrained so that the gas does not diffuse from the arc-extinguishing chamber to the mechanism side, so that the above-mentioned arc driving force is not reduced by half.

FIG. 10 is an example, FIG. 11 is a plan view thereof, and FIG. 12 is a view showing a state in which the contacts are also opened. In the figure, 31, 32
Is a contact, 36 is an arc extinguishing device, 33 is a movable conductor, 37 is a crossbar connected to the mechanism, 38 is a rotation axis of the crossbar, 39 is a rotation axis of the movable conductor, and 34 is a movable conductor. The attached insulating shielding wall, 35 is a rib formed on the body, the arc gas generated in a state where the contacts are separated as shown in FIG. 12,
Shielding wall to prevent flow from contact point to mechanism section (B direction)
The arc is prevented by the ribs 34 and the ribs 35 so that the arc is efficiently driven to the arc extinguishing device 36 side.

In order to prevent the arc generated between the contacts from migrating from the contacts to the fixed part on the mechanical side and onto the movable conductor, fix the part that is difficult to move or attach a tube or plate-shaped insulator to the movable conductor There was something that did.

[Problems of the prior art]

However, the above-mentioned conventional technology has the following problems. That is, in the method according to FIG. 10, the shielding of the space by the closing wall and the rib is performed similarly when the contact is closed and when the contact is open. There is no flow, the heat generated by the contacts 31 and 32 and the heat generated by the conductors are not effectively cooled, the temperature rises too high, the convection of the air inside the circuit breaker deteriorates, and the temperature rise of the entire circuit breaker also increases. It becomes.

When the contacts are open, the shielding wall 34 and the base rib
There was also a problem that the gap of 35 became larger and the shielding efficiency became worse.

[Object of the invention]

Accordingly, the present invention effectively blocks an unnecessary arc gas passage inside the circuit breaker only when the short-circuit current is very strong and the arc cannot be extinguished without controlling the arc gas flow, and the arc gas is removed from the arc extinguishing chamber. To prevent arc gas from diffusing into the circuit breaker, and to guide the arc gas to the outside of the circuit breaker immediately from the exhaust holes, thereby improving the breaking performance and minimizing the deterioration of insulation inside the circuit breaker and the deterioration of the function of the mechanism. In an overload or small short-circuit current region where it is not always necessary to control the arc gas flow under normal conditions, the above-mentioned passage is not blocked, and there is no problem of the above-mentioned temperature rise, and It is an object of the present invention to provide a circuit breaker which prevents an arc from being transferred to unnecessary portions of a movable conductor and a fixed conductor, and which is very simple and inexpensive.

[Means and actions]

In order to achieve the above object, in the present invention, an insulator consisting of a front portion, a bottom view, and a portion close to the bottom of a body is attached to a movable conductor, and an electromagnetic repulsion is generated between the fixed conductor and the movable conductor by a short-circuit current, and Only when the movable conductor rotates in the contact opening direction without waiting for the operation, the above-mentioned front part, bottom part, and body bottom part of the insulator, and a partition plate, body bottom, and body side wall described later. The raw space enclosed by is configured to communicate with the arc-extinguishing chamber to block the gas flow, and in other cases, the gap between the body bottom bottom portion of the insulator and the body bottom is expanded, The air passage can be sufficiently secured, and the heat generated by the conductors, contacts, etc. can be effectively cooled.
In addition, the insulator is mounted on the movable conductor by a shaft that rotatably supports the movable conductor on the crossbar, preventing the number of parts other than the insulator from increasing, and minimizing increases in the number of parts and assembly costs. It is a thing.

Further, by integrally forming the movable insulating portion with the insulator, the arc is prevented from being transferred to unnecessary portions of the movable conductor and the fixed conductor.

〔Example〕

1 to 5 show a first embodiment of a circuit breaker using an insulator according to the present invention.

FIG. 1 is a diagram showing the contacts 7 and 18 of the circuit breaker of the embodiment in a closed state, FIG. 2 is a plan view of the main part thereof, and FIG. Open figure,
FIG. 4 is a cross-sectional view of FIG. 3 viewed from a different direction, and FIG. 5 is a perspective view of the insulator of the present invention.

In FIG. 1, reference numerals 1 and 2 denote an arc-extinguishing chamber 3 and other spaces 4 inside, and a vessel which divides a general space into an inside and an outside except for an exhaust hole 6, and further includes a vessel as shown in FIG. Each pole is separated by body side walls 2 ', 2'.

Reference numeral 5 denotes a partition plate for further partitioning the interior partitioned for each pole into the arc-extinguishing chamber 3 and other spaces 4, and may be a partition wall integrally formed with the bodies 1 and 2 in some cases.

7 and 18 are contacts arranged in the arc-extinguishing chamber 3, 7 is a movable contact fixed to the movable conductor 8, and 18 is a fixed contact fixed to the fixed conductor 9. Reference numeral 19 denotes an arc extinguishing device arranged in the arc extinguishing chamber 3, and in this example, a magnetic arc extinguishing plate is illustrated, but the invention is not particularly limited to this.

The movable conductor 8 is rotatably supported on a crossbar 13 by a shaft 14, and the crossbar 13 is a mechanical unit including a link, a spring, and the like that automatically trips when manually opened / closed or overloaded.
Mechanically connected to 17, the mechanism section 17 crossbar 13 is a body
It is arranged in the other space 4 inside 1 and 2.

Reference numeral 15 denotes a spring suspended between the cross bar 13 and the movable conductor 8, which is suspended in a toggle manner in this embodiment, and the contacts 7, 8 are provided when the movable conductor is located closer to the contact than the dead center. Urges the movable conductor 8 in the direction in which the contacts are closed, and urges the movable conductor 8 in the direction in which the contacts 7, 18 are separated when the movable conductor is located on the contact separation side from the dead center. . The movable conductor 8 extends through the groove 51 of the partition plate 5 and extends from the other space 4 into the arc-extinguishing chamber 3.

10 and 11 are terminals, 12 is a connection conductor for electrically connecting between the movable conductor 8 and the terminal 11, and the electric path is a fixed conductor 9, a fixed contact 18, a movable contact 7, a movable conductor 8 with the terminal 10 as a power supply side. The conductor 12 and the load-side terminal 11 are connected in this order.

Numeral 20 denotes an insulator according to the present invention, which is formed integrally with a movable insulating portion 201, a front portion 202, a bottom view 203, a body bottom proximity portion 204, and a spacer portion 205 as shown in FIG. . In addition, 207 is a rib for reinforcing 202, 203, and 204, and 206 is a hole provided in the spacer portion 205.
As shown in FIGS. 2 and 3, this insulator 20 is
Spacers 205, 205 are narrowly fitted between 13 ′, 13 ′ and the movable conductor 8, and the shaft 14 is inserted through a hole 206 provided in the spacer 205 to be axially mounted on the crossbar 13 together with the movable conductor 8.

As shown in FIG. 3, the movable insulating part 201 substantially covers and insulates the movable conductor 8 on the load side from the movable contact 7 with respect to the fixed conductor 9, and the front part 202 is close to the partition plate 5. Overhanging from the movable insulating part 201 in a substantially parallel shape,
Is disposed between the movable conductor 8 and the body bottom surface 21 on the load side of the shaft 14, and the front portion 202 and the body bottom proximity portion 204 are continuously fleshed and integrated by the bottom portion 203. Also, the front part 202,
Bottom part 203 Container bottom proximity part 204 is provided with partition plate 5 as shown in FIG.
The groove 51 is wider than the groove 51 and almost completely protrudes with a slight gap left between the body side walls 2 ', 2'.

Since the movable conductor 8 and the inner surface of the movable insulating portion 201 and the bottom surface 203 of the insulator 20 are substantially in close contact with each other, and the movable conductor 8 and the insulator 20 are supported by the crossbar 13 by the shaft 14, the movable conductor 8
On the other hand, the insulator 20 is attached substantially integrally, and rotates in accordance with the rotation of the movable conductor 8 as shown in FIGS.

At this time, in either of the states shown in FIGS. 1 and 3, the front portion 202 and the partition plate 5 are arranged close to and substantially parallel to each other. Although the gap is small between the body bottom proximity portion 204 and the body side walls 2 ', 2' as described above,
Only between the ribs 22 and the ribs 22 on the bottom 21 (the ribs 22 need not be present), the bottom portion proximity portion 204 moves in accordance with the rotation trajectory around the shaft 14, and is wide in FIG. In the figure, it is narrow with a slight gap left.

Further, the movable conductor 8 is provided on the side wall of the crossbar 13 as shown in FIG.
The shaft 13 is mounted on the shaft 13 'by a shaft 14 via a spacer portion 205, and is held substantially at the center with the side walls 13', 13 'of the crossbar 13.

In the circuit breaker configured as described above, first, in the contact closed state shown in FIG.
Since there is a wide gap between 4 and the rib 22 on the bottom of the body and it is not shielded, even if the conductors 8, 9 contacts 7, 18 generate heat, air flows in through the gap and is effective Therefore, the conventional problem does not occur.

On the other hand, in the state shown in FIG. 1, if a short circuit occurs on the load-side circuit of the circuit breaker and a very strong short-circuit current passes through the circuit breaker, the short-circuit current causes a strong force between the fixed conductor 9 and the movable conductor 8. The movable conductor 8 instantaneously moves to the shaft 14 without waiting for the rotation of the crossbar due to the operation of the mechanism 17 due to the strong electromagnetic repulsion.
3 in the contact separating direction, and the state shown in FIG. 3 is obtained. At this time, a strong arc and arc gas accompanying the arc are generated between the contacts 7 and 18.

If there is no space generated by the implementation of the present invention described later, the arc gas generated due to the generation of the arc expands instantaneously in the arc-extinguishing chamber 3 and the pressure in the arc-extinguishing chamber 3 rapidly increases. The part is exhausted to the outside of the body through the exhaust hole 6, but the remainder diffuses to fill the other space 4 inside the body, and after the pressure difference between the arc-extinguishing chamber 3 and the other space 4 disappears, the exhaust hole 6 is exhausted. From the body. Usually, the volume of the space of the arc-extinguishing chamber 3 and the volume of the other space 4 is very large, and the time until the pressure difference between the arc-extinguishing chamber 3 and the other space 4 disappears. Is considerably long and the constant pressure is considerably lower than the original pressure in the arc-extinguishing chamber 3, so that it takes time until all the gas inside the body is discharged from the discharge hole 6 to the outside of the body. As a result, the momentum is weak, and for example, it is difficult to expect an improvement in the current limiting performance by pressing the arc against the arc extinguishing device 19 with the arc gas and further guiding the arc to the exhaust hole side. In addition, the arc gas that has spread completely inside the vessel body causes carbonization of the inside corners and adhesion of a metallic arc welded product, and thus easily causes deterioration of insulation resistance performance and mechanism deterioration.

The diffusion of the arc gas from the arc-extinguishing chamber 3 to the other space 4 is performed through a gap between the partition plate 5 and the bodies 1 and 2 and a groove 51 of the partition plate 5, and the main passage is shown in FIG. It is presumed that it is between the movable conductor 8 and the fixed conductor 9 in the groove 51 of the partition plate 5 shown in FIG.

In the present invention, when the movable conductor 8 is separated as shown in FIG. 3, the body bottom proximity portion 204 moves on the rotation locus around the shaft 14 toward the body bottom side, so that the front portion 202 The partition plate 5, the front surface 202, and the bottom plate 203, the body side walls 2 ′, 2 ′, and the body bottom proximity 204 and the rib 22 formed on the body bottom 21 are left with a slight gap. Bottom part 203, near body bottom
204, a small space surrounded by the body bottom surface 21 and the side surfaces 2 ', 2' communicates with the arc extinguishing chamber 3 by the groove 51.

In the present invention described above, the arc gas generated between the contacts 7 and 18 in the state shown in FIG. 3 first fully expands into the arc-extinguishing chamber 3 and then a part of the gas is discharged from the exhaust hole 6 to the outside of the body. But,
Most of the rest flows out of the groove 51 into the aforementioned small space. However, the space volume of the small space is much smaller than the space volume of the other space 4 described above, and is substantially the same as compared with the arc extinguishing chamber 3.
Therefore, the time until the arc gas immediately fills the small space and the pressure difference between the arc extinguishing chamber 3 and the small space disappears is very short. Since the pressure is higher than in the case where there is no small space, an attempt is made to quickly and rapidly exhaust the arc gas from the exhaust hole 6 to the outside of the body after the arc gas is generated.

The arc gas moving at high speed from the small space and the arc-extinguishing chamber 3 toward the exhaust hole 6 blows the arc itself to the arc-extinguishing device 19, so that the arc is extinguished only by the electromagnetic force between the arc and the arc-extinguishing device 19. Since it is faster than being moved to the arc device side and is rapidly cooled and divided, the current limiting effect is also significantly improved.

In the above process, the arc gas diffuses into the other space 4 through the gap, but the amount is very small as compared with the case where the insulator 20 of the present invention is not provided. In addition, problems such as a decrease in insulation resistance due to carbonization and a deterioration in function due to adhesion of an arc melt to the mechanism can be significantly improved.

The arc generated between the contacts is attracted to the magnetic extinguishing device 19 by the magnetic arc extinguishing device 19 and the electromagnetic force of the current of the arc itself, and the movable conductor is located on the load side (left side in the drawing) from the contacts 7 and 18. Since the distance between the fixed conductor 8 and the fixed conductor 9 is smaller than the distance between the contacts 7 and 18, it is likely to shift to the left side of the drawing or to generate a spot. If the arc is partially shifted or spotted to the left of the figure, the arc extinguishing device
Very far from 19, the electromagnetic force between the arc extinguisher 19 and their arcs is also weakened and those arcs are extinguished
Although the arc is hardly attracted to the 19 side and the arc extinguishing performance is reduced, in the present invention, since the movable insulating portion 201 of the insulator 20 is interposed between the movable conductor 8 and the fixed conductor 9, the arc is more leftward than the contacts 7 and 18 in the figure. In this case, the arc is not generated in a transitional or spot-like manner, and all of the arc is strongly sucked by the arc extinguishing device 19 to extinguish the cooling divided arc, thereby improving the arc extinguishing performance.

Also, after the movable conductor 8 has rotated to the position shown in FIG. 3 due to the electromagnetic repulsive force due to the short-circuit current, or in a small short-circuit current region in which the overload or the above-mentioned electromagnetic repulsive force does not occur, the third
Without the state shown in the figure, the crossbar 13 is rotated by the trip operation on the opening and closing mechanism side to reach the state shown in FIG. If the state of FIG. 6 is reached via the state of FIG.
The movable conductor 8 rotated with respect to the
Reset to the state shown in the figure.

In the state shown in FIG. 6, the gap between the body bottom proximity portion 204 and the body bottom rib 22 is widened. However, after the state shown in FIG. 3, the arc is extinguished and the arc gas is discharged. Emissions are almost complete and there is no problem in that regard. In the case of transition from the state shown in FIG. 1 to the state shown in FIG. 6 in an overload or small short-circuit current region, the arc and the arc gas generated originally are small, so that the magnetic arc extinguishing plate 19 alone can sufficiently extinguish the arc. There is little deterioration in performance. In addition, the insulator 20
Since it is fixed to the movable conductor 8 by using 14, only the insulator 20 needs to be added as compared with the conventional circuit breaker, and the increase in the cost of the component assembling process can be minimized.

A spacer 205 integrally formed with the insulator 20 is provided between the movable conductor 8 and the side plates 13 ', 13' of the crossbar 13.
, The movable conductor 8 is correctly positioned substantially at the center with respect to the side walls 13 ′, 13 ′ of the crossbar 13.

FIG. 7 and FIG. 8 show another embodiment of the present invention in which
Can achieve the same effect as that of the first embodiment even if it is almost immediately below the shaft 14 as shown in the figure. The mounting of the insulator 20 on the movable conductor 8 is performed by using the concave portion 209 formed in the spacer portion 205 and the claw. Part 21
A value of 0 allows the same as in the case of the hole 206.

Further, the container bottom surface proximity portion 204 may be formed by using an extended end of the bottom portion 203 as shown in FIG. 9 without using the rib shape described in FIGS.

In the above description, the movable insulating portion 201 has been described as being formed integrally with the insulator 20. However, for example, the main object of the invention can be almost achieved without the configuration of the movable insulating portion. Alternatively, the movable conductor may be covered with a tube or the like separately.

〔effect〕

As described above, in the circuit breaker of the type in which the insulator is attached and the contacts are rapidly separated by using the electromagnetic repulsion generated between the conductors due to the short-circuit current, the conductors and the contacts are not normally energized. Temperature rise can be kept low.In addition, when a very strong arc and arc gas are generated due to the electromagnetic repulsion, the gas passage from the arc extinction chamber to other spaces is blocked. , Preventing the arc gas from diffusing into the circuit breaker, improving the breaking performance, preventing the insulation resistance from lowering, and preventing the mechanical function from deteriorating.
In addition, there is an effect that it is possible to provide a low-cost circuit breaker in which an increase in the number of parts and a complicated assembling operation are minimized.

[Brief description of the drawings]

FIG. 1 is a diagram of a first embodiment of the present invention. FIG. 2 is a plan view of a main part of FIG. 3 FIG. 3 is a diagram of FIG. 1 when a movable conductor is opened by an electromagnetic repulsive force due to a short-circuit current FIG. 5 is a cross-sectional view of FIG. 3 as viewed from the terminal 10 direction. FIG. 5 is a perspective view of an insulator used in the embodiment of FIG. 1. FIG. 6 is a cross-sectional view of FIG. Fig. 7: Another embodiment of the present invention Fig. 8: Perspective view of the same insulator Fig. 9: Another embodiment of the present invention Figs. 10, 11, 12 ... Figs. ... body, 3 ... arc-extinguishing chamber 4 ... other space, 5 ... partition plate (partition wall) 6 ... exhaust hole, 7, 8 ... contact point 8 ... movable conductor, 9 ... fixed conductor 10, 11 terminal, 12 connecting conductor 13 cross bar, 14 shaft 15 contact pressure spring, 17 mechanism part 19 arc extinguishing device, 20 insulator 201 movable Insulation part, 202: Front part 203: Bottom part, 204: Container Body bottom proximity part 205: spacer part, 206: hole 207: rib, 209: concave part 210: nail

──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masazumi Hioka 3-1-24-1 Oshu, Minami-ku, Hiroshima City, Hiroshima Prefecture Inside Templar Industries Co., Ltd. (72) Inventor Tetsuo Furumoto 3 Oshu, Minami-ku, Hiroshima Hiroshima Prefecture Citation No. 1-42 Examiner at Tempal Industrial Co., Ltd. Shinichi Nakagawa (56) References JP-A-61-85741 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) H01H 73/18

Claims (3)

(57) [Claims] An arc extinguishing chamber is provided in the interior of the arc extinguishing chamber. Except for an exhaust hole provided in the arc extinguishing chamber, there is provided a body which divides a general space into an inside and an outside. The internal space for each pole is further divided into an arc-extinguishing chamber and other spaces by a partition plate or a partition wall. Wherein the fixed contact is fixed to a fixed conductor, the fixed conductor is fixed to a power source side external terminal, and the movable contact is fixed to a movable conductor, and the movable conductor is fixed to the fixed conductor. Is connected to the external terminal on the load side via a connection conductor,
The partition plate or the partition wall has a groove for introducing the movable conductor from another space into the arc-extinguishing chamber, and the other space has a direction in which the movable conductor is pivotally supported and the movable conductor is closed by a contact. An open / close mechanism consisting of a link, a spring, etc., which is equipped with a contact bar that biases the contact bar and that automatically trips the cross bar together with the movable conductor or automatically trips due to an overload, etc., has resulted in an extremely large short circuit in the electric circuit. In the case of a circuit breaker that uses an electromagnetic repulsive force generated between the contacts due to the short-circuit current to quickly separate the contacts without waiting for a trip operation of the switching mechanism, the circuit breaker is made of an electrical insulator, and is made of a partition plate or a partition. A front surface portion substantially parallel to the wall, a rotation axis position of the movable conductor or a load terminal side with respect to the rotation axis, and a body bottom proximity portion formed on the body bottom surface side; Continuous between and the bottom proximity A front portion, a bottom portion, and a body bottom proximity portion are formed to a width such that a slight gap is left between the body side walls, and the front portion, the bottom portion, and the body bottom are formed. An insulator consisting of a proximity portion is integrally attached to the movable conductor, and a gap between the body bottom proximity portion of the insulator and the body bottom is large when the movable contact is in close contact with a fixed contact, and a short circuit current is generated. A circuit breaker, which is reduced in a state where only a movable conductor is rotated in a direction to open a contact by an electromagnetic repulsive force. 2. A movable conductor and a spacer narrowly mounted on a side wall of the crossbar are integrally formed near the movable conductor rotating shaft of the insulator, and a hole or a recess is provided in the spacer. The insulator is attached to the movable conductor rotating shaft together with the movable conductor, and the movable conductor is integrally attached with the insulator. Circuit breaker. 3. The insulator according to claim 1, wherein a movable insulating portion interposed between the movable conductor and the fixed conductor is formed integrally with the insulator on the side of the switching mechanism from the movable contact. The circuit breaker according to item 1) or item (2).