JPH0443952Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field The present invention relates to an arc extinguishing device suitably used in a circuit breaker.

Prior Art In a circuit breaker that is connected to an electric circuit and performs opening and closing operations, arcing is unavoidable when the circuit breaker is turned on and off, and an arc extinguishing device has been proposed to reduce and prevent damage to the contacts caused by this. ,It is used.

FIG. 5 1 is a plan view showing the structure of the fixed contact side of a circuit breaker according to the prior art, and FIG. 5 2 is a side view thereof. However, in FIG. 51, the movable contactor 27 shown in FIG. 52 is omitted. Fifth
In Figures 1 and 2, the circuit breaker (not shown) is ON.
It is assumed that the fixed contact 26 and the movable contact 28 are in crimping contact, and the circuit current I is flowing from the terminal member 23 in the direction shown by the arrow.
The circuit current I flowing from the terminal member 23 flows through the end portion 23.
a, each of which is bent at right angles to the plane containing the terminal member 23, and flows through inverted U-shaped arc extinguishing members 24a and 24b disposed parallel to each other to extinguish the arc. The members 24a and 24b meet at the other end, and the fixed contact 25→fixed contact 26→movable contact 2
8 → flows through the path of the movable contact 27. At this time, the current I/2 flowing through each arc extinguishing member 24a, 24b generates magnetic flux that interlinks the arc extinguishing members 24a, 24b. If the circuit breaker is now in the OFF state, the fixed contact 26 and the movable contact 28 will separate, and at this time an arc will occur between both contacts. If the current flowing in this arc is Ia, the magnetic flux and the arc current Ia generate a magnetic force according to Fleming's left-hand rule on the left side of Fig. 5, and this force drives the arc.
It moves to the left in the figure and disappears. The conventional method was to arrange the arc extinguishing members 24a and 24b facing each other in this manner, and to utilize the magnetic flux caused by the current flowing therein and the force caused by the arc current Ia to drive the arc.

Problems to be Solved by the Invention However, in the prior art as described above, the current I flowing from the terminal member 23 is divided into two parts to each arc extinguishing member, and only 1/2 of the current flows through each arc extinguishing member. Therefore, the arc driving force is not generated in excess of the current I minute. Therefore, there has been a demand for an arc extinguishing device that can generate a stronger arc driving force under the same current conditions and has excellent arc extinguishing ability.

The purpose of this invention is to solve the above technical problems,
To provide an arc extinguishing device that has a simple structure and generates a strong arc driving force.

Means for Solving the Problems The present invention provides a fixed contact 6 fixed to the upper part of the fixed contact 5, and a movable contact 8 fixed to the lower part of the movable contact 7 above the fixed contact 5. In an arc extinguishing device for a circuit breaker configured to abut and separate from each other, a terminal member 3 elongated toward a fixed contact 6;
, an end portion 3a of the terminal member 3 extending to one side near the fixed contact 6, first and second leg portions 4c, 4d, and these first
and a first connecting portion 4g that connects the upper portions of the second leg portions 4c and 4d, forming an inverted U-shape.
a, a first current-carrying end portion 13a extending from the second leg portion 4d toward the fixed contact 6, and a direction approaching the terminal member 3 from the first current-carrying path end portion 13a substantially parallel to the longitudinal direction of the terminal member 3. a second energizing path end 13b extending from near the terminal member 3 of the energizing path 13 to the other side; and a third leg 4e continuous to the second energizing path end 13b. A second connecting portion 4h that connects another fourth leg portion 4f and the upper portions of these third and fourth leg portions 4e and 4f.
The first arc-extinguishing member 4 is formed into an inverted U-shape by
a and a second arc-extinguishing member 4b disposed in parallel with
3a, the movable contactor 7 extends in a direction away from the terminal member 3, and connects the terminal member 3, the end portion 3a, and the first arc extinguishing member 4a.
The first energizing path end 13a, the energizing path 13, the second energizing path end 13b, the second arc-extinguishing member 4b, and the fixed contact 5 are formed by punching and bending a single flat plate. This is an arc extinguishing device characterized by:

Function According to the present invention, by connecting the opposing arc extinguishing members so that the same current flows and the current direction is the same, a strong arc driving force is generated and the arc extinguishing action is performed. .

Embodiment FIG. 1 is a partially cutaway sectional view showing a contact portion of a circuit breaker according to an embodiment of the present invention. The handle 2 of the circuit breaker 1 is angularly displaced in the direction indicated by the arrow a (to the right in FIG. The movable contact 8 fixed to the movable contact 7 is in pressure contact with the fixed contact 5 and the fixed contact 6 fixed to the fixed contact 5. The fixed contact 5 extends from the terminal member 3 to the right in FIG. 1 and is integrally formed at one end of the arc extinguishing member 4, which is integrally formed with the terminal member 3. A plurality of ventilation holes 12 are formed in a separator plate 11 provided in a recess 10 of a terminal portion 9 of a circuit breaker 1 . When the handle 2 is angularly displaced in the direction opposite to the arrow a (to the left in Figure 1), the movable contact 7 is spring-biased upward in Figure 1 by an internal mechanism (not shown), and the movable contact 8 is fixed. It separates from contact 6, and the circuit becomes OFF. An arc occurs when these contacts separate from each other.

FIG. 2 1 is a plan view showing the structure on the fixed contact side of an embodiment of the present invention, and 2 is a side view thereof;
3 is a perspective view thereof. A pair of arc extinguishing members 4a and 4b having an inverted U shape are provided perpendicularly to the plane containing the terminal member 3. End portion 3a of terminal member 3
is connected to one leg 4c of the arc extinguishing member 4a, and the other leg 4d of the arc extinguishing member 4a is connected to the current conducting path 13.
The other end 13b of the energizing path 13 is connected to one leg 4e of the other arc extinguishing member 4b. The other leg 4f of the arc extinguishing member 4b is bent at a right angle to form a fixed contact 5, and a fixed contact 6 is fixed to the fixed contact 5. the terminal member 3, arc extinguishing members 4a, 4b,
The energizing path 13 and the fixed contact 5 are integrally formed by punching and bending a single flat plate, so the structure is simple and the assembly cost is reduced.

FIG. 3 1 is a perspective view showing the operation of this embodiment, and FIG. 3 2 is a side view thereof. The operation will be explained with reference to FIGS. 1 and 2. Circuit current I
is assumed to be flowing from the terminal member 3 in the direction shown by the arrow, that is, in the direction path of the terminal member 3 → fixed contact 6 → movable contact 8, and the fixed contact 6 and movable contact 8 are separated, so that there is a gap between the two contacts. It is assumed that an arc 14 is generated due to arc current Ia. The currents I flowing through the arc extinguishing members 4a and 4b are in the same direction,
Further, since the arc extinguishing members 4a and 4b facing each other form a two-turn coil with the current conduction path 13, the magnetic flux 15 shown by the virtual line generated by the current I has the structure described in the prior art section. This is approximately twice as much as in the case of the arc extinguishing member, and therefore a proportional driving force acts on the arc 14. Therefore arc 14
arc extinguishing members 4a, 4b as shown in FIG.
Arc 14a → 14b → 14 in the space sandwiched between
c, and is cooled and disappears by the outside air flowing in through a ventilation hole (not shown) provided close to the terminal member 3 side.

In this arc extinguishing device, the terminal member 3 extends long and narrow in the left-right direction in FIGS. 21 and 2 toward the fixed contact 6. The end portion 3a is located near the fixed contact 6 of the terminal member 3 (to the right in FIGS. 2 1 and 2)
and extends to one side (downward in FIG. 2). The arc-extinguishing member 4a is formed into an inverted U-shape by connecting the upper portions of the leg portions 4c and 4d via the connecting portion 4g. The leg portion 4c continues to the end portion 3a.

The energizing path end portion 13a extends from the leg portion 4b toward the fixed contact 6 (ie, upward in FIG. 21).
The current-carrying path 13 extends from the current-carrying path end 13a in a direction substantially parallel to the longitudinal direction of the terminal member 3 (that is, in the left-right direction in FIGS. 2 1 and 2) and in a direction approaching the terminal member 3 (that is, a second (to the left in FIG. 1) and extends to the vicinity of the terminal member 3. The energizing path end portion 13b extends from near the terminal member 3 (left side in FIG. 2 1) to the other side (upper side in FIG. 2 1). Leg portion 4 of arc extinguishing member 4b
e is connected to the current-carrying path end portion 13b, and this leg portion 4e
The upper parts of the other leg part 4f are connected to each other by a connecting part 4h, and thus the arc extinguishing member 4b is formed in an inverted U-shape as described above. The arc extinguishing member 4b is arranged parallel to the arc extinguishing member 4a.

The fixed contact 5 extends from the leg portion 4f to the current-carrying path end portion 13.
a (downward in FIG. 2) to the vicinity of the current-carrying path end portion 13a.

The movable contact 7 extends in a direction away from the terminal member 3 (to the right in FIGS. 2 1 and 2). The fixed contact 6 is fixed to the upper part of the fixed contact 5. A movable contact 8 is fixed to the lower part of the movable contact 7.

FIG. 4 1 is a perspective view showing another embodiment of the present invention, and 2 is a side view thereof. FIGS. 4 1 and 2 are similar to FIGS. 3 1 and 2, and corresponding parts are given the same reference numerals. What should be noted in this embodiment is that an arc travel plate 16 is formed which is connected to the end of the fixed contactor 5 and extends toward the terminal member 3 side. The operation of this embodiment will be explained with reference to FIGS. 1 and 2.
It is assumed that the direction of the current I is the same as in FIGS. 1 and 2. The arc 14 initially occurs between the fixed contact 6 and the movable contact 8, and if the arc running plate 16 were not present, the arc 14 would curve and still exist between both contacts, but if the arc running plate 16 is present. Therefore, its path quickly leaves both contacts due to the aforementioned driving force, moves sequentially to the left in FIG. 42 like the arcs 14a to 14d, and disappears. Therefore, damage to the contacts is reduced and prevented, and the reliability and life of the contacts can be increased.

Effects As described above, according to the present invention, it is possible to obtain a strong driving force with a simple structure, so the arc extinguishing ability is increased, thereby achieving high reliability and
A circuit breaker having a long-life contact structure can be realized.

In the present invention, the first and second arc extinguishing members 4a, 4
b and the energizing path 13 contribute to arc drive, so the arc extinguishing ability is increased as described above.

Further, in the present invention, the terminal member 3, the end portion 3a and the first
Arc extinguishing member 4a, first energizing path terminal 13a, and energizing path 1
3, the second current-carrying path terminal 13b, the second arc-extinguishing member 4b, and the fixed contact 5 are formed by punching and bending a single flat plate, thus achieving the excellent effect of being extremely easy to manufacture. be done.

[Brief explanation of the drawing]

A partially cutaway sectional view, FIG. 2 1 is a plan view showing an embodiment of the present invention, FIG. 2 2 is a side view thereof, FIG. 2 3 is a perspective view thereof, and FIGS. FIG. 4 is a perspective view showing the operation of one embodiment; FIGS. 1 and 2 are perspective views and side views of another embodiment of the present invention; FIGS.
FIG. 1 is a plan view and a side view showing a conventional technique. 3, 23...terminal member, 4, 4a, 4b, 24
a, 24b... arc extinguishing member, 5, 25... fixed contact, 6, 26... fixed contact, 7, 27... movable contact, 8, 28... movable contact, 13... energizing path,
14...Arc, 16...Arc traveling plate, I...
Circuit current.

Claims (1)

[Claim for Utility Model Registration] A movable contact 8 fixed above the fixed contact 5 and below the movable contact 7 is brought into contact with a fixed contact 6 fixed on the upper part of the fixed contact 5. and an arc extinguishing device for a circuit breaker configured to be spaced apart, the terminal member 3 extending in an elongated direction toward the fixed contact 6.
, an end portion 3a of the terminal member 3 extending to one side near the fixed contact 6, first and second leg portions 4c, 4d, and these first
and a first connecting portion 4g that connects the upper portions of the second leg portions 4c and 4d, forming an inverted U-shape.
a, a first energizing path end portion 13a extending from the second leg portion 4d toward the fixed contact 6, and approaching the terminal member 3 from the first energizing path end portion 13a substantially parallel to the longitudinal direction of the terminal member 3. An energizing path 13 extending in the direction close to the terminal member 3, a second energizing path end 13b extending from the terminal member 3 side of the energizing path 13 to the other side, and a third leg continuous to the second energizing path end 13b. 4e, another fourth leg portion 4f, and a second connecting portion 4h that connects the upper portions of the third and fourth leg portions 4e and 4f.
The first arc-extinguishing member 4 is formed into an inverted U-shape by
a and a second arc-extinguishing member 4b disposed in parallel with
3a, the movable contactor 7 extends in a direction away from the terminal member 3, and connects the terminal member 3, the end portion 3a, and the first arc extinguishing member 4a.
The first energizing path end 13a, the energizing path 13, the second energizing path end 13b, the second arc-extinguishing member 4b, and the fixed contact 5 are formed by punching and bending a single flat plate. An arc extinguishing device characterized by: