JP2965332B2 - Circuit breaker - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical field to which the invention pertains] The present invention relates to a type in which, when a short circuit occurs, a crossbar is rotated by an opening operation of an opening / closing mechanism to open a contact and cut off a current. Improve current limiting performance and insulation performance of circuit breakers,
In addition, the present invention relates to improvement of an insulator attached to a crossbar or a movable conductor for the purpose of 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.

[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]

Therefore, the invention of the present invention, when the contact is opened and an arc is generated, effectively shields an unnecessary arc gas passage to prevent the arc gas from diffusing from the arc extinguishing chamber into the circuit breaker,
It guides the arc gas to the outside of the circuit breaker immediately from the exhaust hole, improves the breaking performance, and also minimizes the deterioration of the insulation inside the circuit breaker and the deterioration of the function of the mechanism. It is an object of the present invention to provide a circuit breaker very simply and inexpensively, in which the above-mentioned passage is not shielded and which does not have the above-mentioned problem of temperature rise.

[Means and actions]

In order to achieve the above object, according to the present invention, an insulator consisting of a front portion, a bottom portion, and a portion near the bottom of a body is attached to a crossbar or a movable conductor, or is formed integrally with a crossbar made of an insulator, and is short-circuited. When the contact is opened by rotating the crossbar by the operation of the mechanism by the electric current, the front part, the bottom part, and the part near the body bottom of the insulator and the partition plate, the body bottom, and the body side wall described later. The gas flow is shielded by configuring the small space enclosed by with the arc-extinguishing chamber, and in the normal energized state, the gap between the vicinity of the body bottom of the insulator and the body bottom is widened. In addition, a sufficient air passage can be ensured, so that heat generated by conductors, contacts, and the like can be effectively cooled.

〔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 a main part thereof, and FIG. 3 is a cross-sectional view of the state shown in FIG. 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. The crossbar 13 is a mechanism unit 17 including a link, a spring, and the like, which automatically trips due to manual opening / closing or overload.
The mechanical section 17 and the crossbar 13 are mechanically connected to
It is arranged in the other space 4 inside 2.

The movable conductor 8 slightly rotates about the shaft 14 and the contacts 7, 18 are urged against the crossbar 13 by a spring (not shown) in the closing direction. 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.

Reference numeral 20 denotes an insulator according to the present invention, as shown in FIG.
2. The bottom part 203, the body bottom part proximity part 204, and the spacer part 205 are integrally formed, and are made of an electrically insulating material. Note that
207 is a rib for reinforcing 202, 203, 204, and 206 is a hole provided in the spacer portion 205. This insulator 20
As shown in FIGS. 2 and 3, spacers 205, 205 are narrowed between the crossbar side walls 13 ', 13' and the movable conductor 8, and the shaft 14 is inserted through a hole 206 formed in the spacer 205. And is mounted on the crossbar 13 together with the movable conductor 8.

The front part 202 is close to and substantially parallel to the partition plate 5, and the body bottom proximity part 204 is arranged between the movable conductor 8 and the body bottom 21 on the load side with respect to the rotation axis 15 of the crossbar 13. The front portion 202 and the body bottom portion proximity portion 204 are continuously fleshed and integrated by the bottom portion 203.

In addition, the front part 202, the bottom part 203, the body bottom proximity part 204,
As shown in FIG. 2, the partition wall 5 is wider than the groove 51 of the partition plate 5 and almost completely protrudes with a slight gap left between the body side walls 2 ', 2'.

The crossbar 13 and the inner surface of the bottom surface 203 of the insulator 20 are almost 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. Are mounted substantially integrally, and rotate as the crossbar 13 rotates as shown in FIGS.

At this time, in each 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 between the bottom surface proximity portion 204 and the body side walls 2 ', 2' is small as described above, the rib 22 between the body bottom proximity portion 204 and the body bottom surface 21 (even if the rib 22 is not provided). Only during (good), the body bottom proximity portion 204 moves in accordance with the rotation locus about the rotation shaft 15, and is wide in FIG. 1 and narrow with a slight gap in FIG.

Further, the movable conductor 8 is provided on the side wall of the crossbar 13 as shown in FIG.
13 ', 13' are mounted on a shaft 14 via a spacer portion 205, and are held substantially at the center with respect to 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.
There is a wide gap between 204 and the rib 22 on the bottom of the body,
Since it is not shielded, even if the portions of the conductors 8 and 9 at the contacts 7 and 18 generate heat, the air flows through the gaps and is effectively cooled, so that the conventional problem does not occur.

On the other hand, in the state of 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 short-circuit (not shown) included in the mechanism unit 17. The crossbar 13 connected to the mechanism section 17 by the operation of the sensor rotates in the contact separating direction about the rotation shaft 15, 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 pressure in the arc extinguishing chamber 3, so that it takes time until all the gas inside the body through the discharge hole 6 is discharged outside the body. Therefore, for example, it is difficult to expect the current limiting performance to be improved 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 contacts 7, 18 are separated as shown in FIG. 3, the body bottom proximity portion 204 moves on the rotation locus about the crossbar rotation shaft 15 toward the body bottom. Therefore, the partition plate is left with a slight gap between the front part 202 and the partition plate 5, the bottom part 203 and the body side walls 2 ', 2', the body bottom proximity part 204 and the rib 22 formed on the body bottom 21. 5, Front 202, Bottom 20
3. The small space surrounded by the container bottom proximity portion 204, the container bottom 21, and the side surfaces 2 ', 2' is configured to communicate 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. In addition, since the insulator 20 is fixed to the crossbar 13 using the shaft 14, only the insulator 20 needs to be added as compared with the conventional circuit breaker, minimizing the cost increase in the component assembly process. It is held down. Further, since the spacer portion 205 integrally formed with the insulator 20 is narrowly provided between the movable conductor 8 and the side plates 13 ', 13' of the crossbar 13, the side walls 13 ', 13' of the crossbar 13 are provided. In contrast, the movable conductor 8 is correctly positioned substantially at the center.

6, 7 and 8 show another embodiment, and the same effect as that of the first embodiment is realized even when the body bottom proximity portion 204 is almost directly below the rotating shaft 15 as shown in the drawing. Yes, and crossbar 13
Attachment of the insulator 20 to the insulator 206 can be performed by the concave portion 209 and the claw portion 210 as in the case of the hole 206.

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

FIG. 13 to FIG. 16 show a cross bar 13 formed of an insulating material in still another embodiment, a rotating shaft 15, a front portion 202, and a body bottom proximity portion 2.
04 is formed integrally with the crossbar 13;
The effect is the same as the case where the cross bar 13 and the insulator 20 of the first embodiment of FIGS. 1 to 3 are separately formed and combined. [Effect] As described above, the insulator according to the present invention is attached. Or, in a circuit breaker integrally molded with a crossbar, the temperature rise of conductors and contacts can be kept low in a normal energized state, and furthermore, the mechanism breaks the contacts due to a short circuit, and a very strong arc and arc gas When the arc occurs, the gas passage leading from the arc extinguishing chamber to the other space is blocked, preventing the diffusion of arc gas into the circuit breaker, improving the breaking performance, preventing the insulation resistance from lowering, and deteriorating the mechanical function. This has the effect of providing a low-cost circuit breaker that is prevented, and the increase in the number of parts and the complexity of the assembling work 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 cross-sectional view of FIG. FIG. 4 is a cross-sectional view of FIG. 3 viewed from the terminal 10 direction. FIG. 5 is a perspective view of an insulator used in the first embodiment. FIGS. 6 and 7 are views of another embodiment of the present invention. Fig. 8: Fig. 9 of another embodiment of the present invention Fig. 9: 図 Fig. 10, 11, 12 ... Fig. 13 of conventional example Fig. 13, 14, 15, 16 ... Fig. 1 of another embodiment of the present invention , 2 ... container, 3 ... arc extinguishing chamber 4 ... other space, 5 ... partition plate (partition wall) 6 ... exhaust hole, 7,18 ... contact point 8 ... movable conductor, 9 ... Fixed conductors 10, 11… Terminals, 12… Connection conductors 13… Crossbars, 14… Shafts 15… Rotating shafts, 17… Mechanical parts 19… Arc extinguishing devices, 20… Insulators 202… … Front, 203… Bottom 204… Near the bottom of the body 205… Spacer 206… Hole, 207 ... Rib 209 ... Recess, 210 ... Claw

──────────────────────────────────────────────────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 is rotatably supported on the movable conductor in a direction in which the movable conductor is closed. A circuit breaker, comprising: a crossbar equipped with a contact spring to be energized, and a switching mechanism including a link, a spring, and the like, which automatically opens and closes the crossbar together with the movable conductor or detects an overload short circuit or the like. It is made of an insulating material, and is formed on the front surface portion substantially parallel to and close to the partition plate or the partition wall, on the rotation axis position of the crossbar or on the load terminal side with respect to the rotation axis, and formed on the bottom side inside the body. A bottom part close to the body, a bottom part which is continuously fleshed between the front part and the bottom part, and the front part, the bottom part, and the bottom part close to the body leave a slight gap between the body side walls. The front part An insulator consisting of a bottom portion and a body bottom proximity portion is integrally attached to a crossbar or a movable conductor, and a gap between the body bottom proximity portion of the insulator and the body bottom is such that the movable contact closes to a fixed contact. The circuit breaker is characterized in that the circuit breaker is large in a state in which the crossbar and the movable conductor are rotated in a direction in which a contact is separated by the action of a mechanism unit due to a short-circuit current. 2. The insulator is formed separately from the crossbar, and a movable conductor and a spacer narrowed on a side wall of the crossbar are integrally formed near the movable conductor rotation axis of the insulator. The insulator is integrally attached to a crossbar or a movable conductor by forming a hole or a recess in the spacer portion, supporting the insulator together with the movable conductor on the movable conductor rotating shaft, and integrally attaching the insulator to the crossbar or the movable conductor. Claim (1)
Circuit breaker described in the paragraph. 3. The circuit breaker according to claim 1, wherein said front part, bottom part and body proximity part are formed integrally with a crossbar made of an insulating material. .