JPS5846540A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a circuit breaker69, and particularly relates to a circuit breaker with improved current-limiting performance during interruption.

Figure 1(a) is a cross-sectional plan view showing a general circuit breaker, and Figure 1(b) is Mb+bl of Figure 1(a).
FIG.

In the figure, (1) is an enclosure made of insulators, which circuits and constitutes the outer frame of the interrupter, and (2) is a fixed conductor ('20
1) is a fixed contactor with a fixed contact (202) fixed to the tip; (3) is a movable conductor (801) with a movable contact (202) fixed to the tip;
202) is fixed to the movable m* tentacle, (4) is the movable tdJ rod, (3) the operating mechanism section for operating the t-t, and (5) is the arc extinguishing plate 1.
．． The connection is an exhaust hole formed in the enclosure (1), and A is both contact points (202).

(802) indicates an arc occurring between.

In the circuit breaker with the above configuration, the town m torsion point (80
2) and the fixed contact (202) are closed, the current flows from the fixed conductor (201) to the fixed contact (202) to the movable contact (
802)→flows along the path of the movable conductor (801).

In this state, when a large current such as a short circuit current flows through this circuit, the operating mechanism section (4) is activated and the 0T torsion point (8
02) Open from the t-fixed contact (202). At this time, an arc A is generated between the fixed contact (202) and the movable contact (802), and the arc A is generated between the fixed contact (202) and the movable contact (802).
2) An arc voltage is generated between the two. This arc voltage increases as the separation distance of the glue # contact (802) from the fixed contact (202) increases. At the same time, the arc A is attracted by the magnetic force and extends in the direction of the arc extinguishing plate (5), so that the arc cross-sectional area further increases.

In this way, the arc current reaches the current zero point, the arc A'f: is extinguished, and the interruption is completed. During such critical operation, the movable contact (802) and the fixed contact C20
2,), a large amount of energy is generated by the arc A in a short period of time, ie, within a few milliseconds. Therefore, the temperature of the gas inside the enclosure (1) rises, and the pressure also rises rapidly.
1) is released into the atmosphere.

The circuit interrupter and its internal components operate as described above when interrupting the circuit.Next, the operations of the fixed contact (202) and the movable contact (8G2) will be specifically explained. Generally, arc resistance R is given by the following formula. That is, R constraint e- However, R: Arc resistance (Ω) e: Arc resistivity (Ω, tx) l: Arc length @L) - 8: Arc cross-sectional area (7) - When the arc length l is 50 inches or less In the short arc A, the arc space is occupied by metal particles. Moreover, this release of metal particles occurs in a direction perpendicular to the contact surface. In addition, the ejected metal particles have a temperature close to the boiling point of the metal at the contact point at the time of ejection, and as soon as they are injected into the arc space, they are injected with electrical energy to become high temperature and high pressure, and conduct It flows away from the conductor at high speed while expanding in the same direction as the pressure distribution in the arc space. - The arc resistivity p and the arc cross-sectional area SII'i in the arc space are determined by the amount of metal particles generated and the direction in which they are released. therefore,
The arc voltage is also determined by the behavior of metal particles. Next, the behavior of such metal particles will be explained using Section 2.

In Figure 2, (202) is the fixed ridge point, (802) is the point 1, and the contact points (202) and (8
The respective X planes of 02) are contact points (202) and (802)
1 on the opposing surface when vibrating, contact point C202),
Each of the seven faces of C802) covers a portion of the contact surface and conductor surface other than the opposing X face. In addition, the ring 2 shown by the dashed line in the figure indicates the outer circle of the arc A that occurs between the dotted line (202) and (802). Furthermore, metal particles a and metal particles S are schematic representations of metal particles emitted from the X-plane and 7-plane of the contacts (202) and (802) by evaporation, etc., and the emission directions are respectively This is the direction of each streamline drawn by arrow m and arrow n.

The metal particles at b emitted from such contacts (202) and (802) rise from about 8,000°C, which is the boiling point temperature of a conductive metal, to a temperature that becomes conductive due to the energy in the arc space, that is, 8,000°C. The arc is externally heated to a temperature of 20,000° C. or higher, or even higher, about 20,000° C., and in the process of external heating, energy is removed from the arc space, lowering the temperature of the arc space, and as a result, increasing the arc resistance R1-. Note that the amount of energy taken away by metal particles amb from the arc space increases as the degree of external temperature of the metal particles increases, and the degree of external temperature is
It is determined by the position of the metal particles a+b emitted from the arc space and the emission meridian.

However, in the conventional circuit breaker shown in Figure 2,
The metal particles a emitted from near the center of the opposing surface XIm release a large amount of energy from the arc space. The amount of energy taken away from the arc space is small. That is, in the range where metal particles A flow, a large amount of energy is taken away to lower the temperature of the arc space, thus increasing the arc resistivity P, but in the range where metal particles A flow, a large amount of energy t-S is not lost. Ark space! The decrease in i degree is small, and therefore the arc resistivity e cannot be increased, and the opposing surface X1lffij
, - and the Y-face of the contact, the arc cross-sectional area also increases and the arc resistance decreases.

Since the outflow of energy from the arc space due to such metal particles is balanced with the electrically injected energy, if the injection of metal particles generated between the points into the arc space is increased, the arc It is thought that the temperature of the space is greatly reduced, and as a result, the arc resistivity is increased, and the arc voltage and metal value can be greatly increased.

On the other hand, another major drawback of the conventional inertia conductor is that the arc leg tends to expand directly to the part where it meets the conductor, which is generally provided on the Y plane. This heat causes the low melting point of the torsional member to melt, causing the contact to fall off at the pressure point.

This construction was made to improve the above-mentioned conventional drawbacks, and on each conductor of a pair of screw contactors that perform opening and closing operations,
By arranging a pressure reflector made of an electrically insulating material made of a resin material containing inorganic powder so as to surround the outer periphery of the adult fish, it is possible to generate a high arc voltage and The purpose of the present invention is to provide a circuit interrupter that has good current limiting performance and is free from the risk of contacts falling off.

Embodiments of the present invention will be described below based on the drawings. f
88(1) is a plan cross-sectional view of one embodiment of the Ill device according to the present invention, and FIG. 8(b) is a side I! at 411 bg-bm of FIG. 8(a). Fr direction map is available. In FIGS. 8(a) and (b), the enclosure (1)
is made of an insulator, forms the outer frame of the switchgear, and is provided with a discharge port (101). Fixed method tentacle (2)
A fixed conductor (201) fixed to the enclosure (1) and a fixed contact (2) attached to one end of the fixed conductor (201).
02). The Machido Takeshi contactor (3) opens and closes with respect to the fixed screw contactor (2), and the fixed conductor (20
1) consists of a movable conductor (80 points) that opens and closes with respect to The operating mechanism section (4) is for opening and closing the movable contactor (3).The arc extinguishing plate (s) 11 has a movable H point (
8o2) Kaz fixed point (202) Karae! This is to extinguish the arc that occurs when moving J4m. (6).

(7) is a plate-shaped pressure reflector arranged on the conductors (201) and (801) of both carrier probes (2) and (3), respectively. They are made of electric material made of a resin material containing Wi111 powdered wood, and are provided so as to face each other and surround each fold point (202), (208).

Now, if the town moving station (802) and the fixed point (202) are closed, the current flows from the fixed conductor (201) to the fixed point (202).
02) -> town moving point (802) -> movable conductor (801), flowing from the power supply side to the load side. In this state, if a large current such as a short circuit current flows through this circuit, the operating mechanism (
4) is activated to move the movable fold point (802) to the fixed fold point (20
2) Separate from. At this time, fixed ship point (!02)
An arc A occurs between and the moving score (802). In this arc A, as shown in Fig. 4, a pressure reflector (a
The metal particles are reflected by L (7), creating a high pressure between the arcs 1, and as a result, the arc is effectively cooled and extinguished.

Hereinafter, the behavior of the circuit interrupter of the present invention as shown in FIG. 8 will be explained with reference to FIG. 4. In other words, space qic's? The pressure value of the arc A cannot exceed the pressure value of the space within the arc A itself, but it is at least an overwhelmingly higher value than the case where the pressure reflector (a) e (7) is not provided. shows. Therefore, the surrounding space Qri with a fairly high pressure generated by the pressure reflector (als (7)) provides a force that suppresses the spread between arc AO!2 and ``squeezes'' arc A into the narrow space. This means that the opposite surface
Streamlines of metal particles emitted from the surface, such as C, mwot-
It becomes Jin, who is trapped in the arc space. Therefore, the emitted metal particles asC are effectively injected into the arc space. As a result, a large amount of effectively injected metal particles (a+C) remove a large amount of energy from the arc space, which is incomparable with conventional devices, and thus cool the arc space (t-) properly. This force significantly increases the resistivity P, that is, the arc resistance R, and the arc voltage.

Also, due to the presence of these pressure reflectors (6) and (7), the foot of arc A becomes difficult to expand toward the Y plane, and the contact point (j1
02).

The legs of the arc no longer come into contact with the joints between (802) and the conductors (!!01) and (801), and as a result, adult fish are prevented from falling off.

Furthermore, the pressure reflector in this invention is made of inorganic powder t-
Since it is made of a dense material made of a gold-containing resin material, when a high temperature arc occurs, the resin material thermally decomposes due to the temperature rise and generates decomposed gas. The energy consumption accompanying the generation of this decomposed gas deprives the arc of energy and cools it. In addition, the pressure on the surface of the pressure reflector increases due to the generation of decomposed gas, and the opening speed of the contactor can be increased due to the narrowing of the arc. In this manner, in the circuit breaker of the present invention, the effects unique to the constituent materials of the pressure reflector are added to the effects of the pressure reflector itself, making it possible to further increase the arc voltage.

On the other hand, when the pressure reflector is made of only a resin component, the effect of the decomposition gas generated during thermal decomposition is good in terms of shadow flow performance. However, with only a resin component, the heat resistance and mechanical strength are insufficient, and the pressure reflector itself is significantly worn out due to repeated arcing.
There is a problem in terms of lifespan, as it deteriorates and eventually disappears. 'Since the pressure reflector of this invention contains inorganic powder in the resin material, it has better heat resistance and mechanical strength compared to a resin alone69, and has far superior thermal conductivity. When exposed to the high temperature of the arc, the temperature rise of the pressure reflector itself is suppressed, and it has good resistance to deterioration and wear, resulting in a long life, and the effects of decomposed gas are almost the same.

As the inorganic powder, powders of alumina, borax, mica, calcium carbonate, etc., which are generally used as fillers or aggregates, can be used.

In addition, as a resin component, when removed from the high temperature of the arc,
It is desirable to use a resin that vaporizes in a sublimation-like state without precipitating carbonaceous components, such as acetal-based, acrylic-based, fluorine-based, V-licon-based, polyimide-based, and drill-based resins. On the other hand, phenolic resins and the like are unsuitable because they undergo thermal decomposition and precipitate carbonaceous components, resulting in a decrease in MEG resistance pressure.

Note that resin materials containing such inorganic powders are inexpensive, and can be processed using the same method as the above-mentioned resin alone, and can also be processed by die cutting.

The pressure reflector can have any shape. For example, in the above embodiment, the pressure reflector to)+ (7) is plate-shaped;
As shown in the plan view of the conductor (201) of each forceps (2)e (a), by taping, coating, etc.
, (gol).

Further, in this invention, at least one of the pressure reflectors includes:
An arc path may be formed that originates at the contact point and extends away from this point and has a higher conductivity than the pressure reflector. Due to the existence of such an arc travel path, the legs of the arc move quickly along the arc travel path, making it easier for the arc to contact the arc extinguishing plate and be cooled down, thereby further improving the interruption performance.

Fig. 6 (5K) is a side view of an embodiment of the pressure reflector (aL (7)) forming the arc travel path, Fig. 6 (b) is its plan view, #I6 Fig. (C) is W, C1- in Figure 6 (a)
A cross section of C1 is shown. In this embodiment, the arc traveling path is a pressure reflector (e), t(υ), a conductor (201), (801) and a groove (601) where the surface is exposed.

(701) is formed by k.

- Fig. 7(a) is a side view of another embodiment of the pressure reflector (a)s (7) forming the above-mentioned arc travel path, Fig. 7(b)
) is its plan view, and Fig. 7(c) is c2- of Fig. 7(a).
A Cm cross-sectional view is shown. In this embodiment, the arc traveling path is the convex part (801) of the conductor (201, 1° (801)), (90
1) The conductor surface has a pressure reflector (a
) * The grooves (601) and (701) in Figure 6 of Figure 6 of (y) protrude higher than the grooves (601) and (701), and the arc A moves faster than the grooves (601) and (701) shown in Figure 6. This has the effect of further improving performance.

As described above, according to the present invention, the arc space is effectively cooled by the pressure reflector, the arc extinguishing performance is increased, and spot dropout is also prevented. It is possible to obtain a narrowing effect and an effect of improving the opening speed, and also to have a long life.

Furthermore, by adopting a configuration in which an arc travel path is formed in the pressure reflector, the effect of further improving the breaking performance can be achieved.

[Brief explanation of the drawing]

Figure 1 (a) is a plan view showing a general circuit breaker, Figure 1 (b) is a sectional view at 1 m bs-1) + of Figure 1 1a), and Figure 2 is the circuit of Figure 1. FIG. 8(a) is a schematic illustration of the behavior of metal particles in a circuit breaker, and FIG. 8(b) is a plan view showing an embodiment of the circuit breaker according to the present invention.
) is a side cross-sectional view at line -b in Figure 8(a), Figure 4 is a schematic explanatory diagram of the behavior of metal particles in the circuit breaker in Figure 8, and Figure 5(a) is a cross-sectional view at line -b in Figure 8(a). Water other examples of reflectors 1i111! Figure j, Figure 6(b) is Figure 6(a)
The plan view of FIG. 6 (Jl) shows the other 5j! Example T-Boss; Figure, Figure 6 (
b) is gga diagram (a) (D plan view, Figure 6 TC) is #! of Figure 6 (a). Cross-sectional view at cl-C, Fig. 7 (
a is another example t of a pressure reflector forming an arc travel path
-Boss 1141 view, Figure 7(b)! The plan view of @7 (a) and Figure 7 (c) are the lines c2-C of @7 (a),
FIG. (2)...Fixed number of touches, (3)...Movable range of touches, (
a) + (7)...Pressure reflector, (201)-...Fixed conductor, (202) =, Ia constant torsion a, 2. The same reference numerals in the drawings indicate the same or corresponding parts. Agent Shin Kuzuno - (1 other person) Figure 1 (a) Figure 1m (b) Figure 2 Figure 4 Figure 3 (a) 4 Figure 3 (b) Figure 5 (b) Figure 6 (b) Figure 7 (b) Procedural amendment (spontaneous) Commissioner of the Japan Patent Office 1, Indication of the case Patent application No. 56-444154
No. 2, the name of the invention, interrupter 3, the person making the amendment, the "Detailed Description of the Invention" column of the specification subject to the amendment. Details of the amendment (1) The detailed calculation will be corrected as follows. Page line correction Previous correction
Positive after -678,00σ(”! 3.000
°C (more than)

Claims (1)

[Claims] (1) Completely equipped with at least one pair of contactors, each consisting of a conductor and a dot fixed thereto, for opening and closing operations;
On each conductor of the pair of electric contacts, a pressure reflector made of an electrically insulating material made of a resin material containing Tsubame Isobake powder is arranged so as to be recessed by 9 degrees around the outer periphery of the point. A circuit breaker. (2) The circuit breaker according to claim 1, wherein the pressure reflector covers the tip of the electric contact. (3) The circuit breaker according to claim 1, wherein the pressure reflector is made of a plate material. (4) At least one of the pressure reflectors is formed with an arc traveling path starting from the dot and extending away from the dot, and having higher conductivity than the pressure reflector. The circuit breaker according to item 1, 2 or 8. (6) The circuit breaker according to claim 4, wherein the arc traveling path is formed of a groove exposed on the conductor surface 1. (6) A circuit breaker according to claim 6, wherein the surface of the conductor forming the arc traveling path protrudes beyond the surface of the pressure reflector.