JPS6049524A - 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] [Technical field of invention] This invention relates to a circuit breaker.

[Prior art]

Figures 1 to 3 are cross-sectional views showing conventional circuit breakers.
Each shows a different operating state.

(υ is a cover, <2) is a base, and the cover (υ and base (2) constitute a container (3). (4) is a fixed contact, and one end of its fixed conductor (5) is It has a fixed contact (6), and the other end is a terminal part to be connected to an external conductor (not shown). (7) is a movable contact, and one end of the movable conductor (8) The fixed contact (6) has a movable contact (9) facing +C. αQ is a movable contact device, and (B) is a movable arm, which is fixed to the crossbar U and is opened and closed when each pole is spaced. μ is an arc extinguishing chamber, and an arc extinguishing plate O→ is held by a side plate 0Q. αQ is a toggle link 41, which is composed of an upper link αη and a lower link (T). One end of the upper link αη is connected to Freddle 01, and the other end is connected to one end of the lower link (to) by shafts (7) and υ.The other end of the lower link (to) is It is connected to the movable arm Uυ of the movable contact device α1. (A) is an adjustable operating handle, and 2 is an operating spring, which is connected between the axis CD of the toggle link mechanism aQ and the operating hand lv@. (c) and (c) are the sliding and electromagnetic pulling mechanisms, respectively, and when activated, the retracting bar (e) is moved by the bimetal/L') and movable iron core (a), respectively. It is designed to rotate clockwise. (G) is a latch whose one end is locked to the trip bar (7) and the other end is locked to Credo/kQ'J.

When Credo/L' 4 is locked to the latch (E), tilt the operating hand/I/@ to the closing position to activate the toggle link mechanism a.
Q is extended, the axis Qυ is locked to the credo /l' (11), and the movable contact (9) is joined to the fixed contact (6). This state is shown in FIG.

Next, when the operation handle @ is tilted to the open position, the toggle link mechanism is bent to open the movable contact (9) from the fixed contact (6), and the movable arm (B) engages with the fredle shaft (A). will be stopped. This state is shown in FIG. Also, the above 1st (8)
When an overcurrent flows through the circuit in the closed circuit state shown in Fig. 1, the thermal tripping mechanism cl/Q or the electromagnetic tripping mechanism (c) is activated to release the engagement between the credo lva* and the latch (a), causing the credo shaft to disengage. (to) in a clockwise direction
is rotated and the stopper shaft (latched first. Credo IVA
Since the connecting point between * and upper link 0η crosses the line of action of the above operating spring), the toggle link mechanism QQ is bent by the spring force of the operating spring), and each pole is interlocked with the crossbar @ to automatically shut off. Do the following. This state is shown in FIG.

Next, the behavior of the arc that occurs when the circuit breaker interrupts the current will be explained.

Now, when the movable contact (9) and the fixed contact (6) are in contact, the power is transferred from the power supply side to the fixed conductor (5).
), fixed contacts (6), movable contacts (9) and movable conductors (
8) and is supplied to the load side. In this state, when a large current such as a short-circuit current flows through this circuit, the movable contact (9) is separated from the fixed contact (6) as described above.
9) An arc 0'4 is generated between the fixed and movable contacts (Ci), and an arc voltage is generated between the fixed and movable contacts (Ci). This arc voltage increases as the separation distance of the movable contact (9) from the fixed contact (6) increases, and at the same time, the arc (at the same time) is attracted and expanded in the direction of the arc extinguishing plate Q4 by magnetic force. and further rises.

In this way, the arc current reaches the current zero point, the arcs C are extinguished, and the interruption is completed. During such a break-opening operation, a large amount of energy is generated between the movable contact (9) and the fixed contact (6) due to an arc within a short period of time, ie, within a few milliseconds. Therefore, the temperature of the gas inside the container (3) rises, and the pressure also rises rapidly, but this high-temperature, high-pressure gas flows into the outlet formed on the side wall of the container (3) on the power supply side. released into the atmosphere.

In the operation of the circuit breaker as described above, arc resistance R is generally given by the following formula.

In other words, where, R: arc resistance (Ω) ρ: arc resistivity (Ω, α) S: arc length 3) S: arc runner area (d) However, in general, at a large current of several KA or more and with an arc length e In short arc runners with a diameter of less than 50 mm, 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, these released metal particles are
At the time of release, the temperature is close to the boiling point of the metal at the contact point,
Furthermore, as soon as it is injected into the arc space, the injection of electrical energy is stopped and the temperature and pressure are increased.

If the contacts (i) and (9) are exposed for a long time under such conditions, it is likely that the contacts (6) and (9) will melt. ), as shown in (B), an arc runner is disposed on the rear side of the contact fixing position at the fixed conductor (5).

This can be done by quickly transferring the foot of the June rule of the fixed contact (to the arc that occurred between the contact point (6) and t (9)) to the arc runner ■.
The main purpose is to protect 9).

However, in the above case, even if the arc (to the arc) is dislocated to the arc runner, it is difficult to completely separate from the fixed contact (6), and the arc current when this dislocation occurs is as indicated by the arrow in Fig. 4 (B). As shown, since the current flows from the base end of the fixed conductor (5) to the arc runner by bypassing the fixed contact (6), the fixed contact (6) is overheated by the passage of the current, and therefore the contact (( It had the disadvantage of being easily worn out.

[Summary of the invention]

This invention was made in order to eliminate the drawbacks of the above-mentioned conventional ones, and the tip of the conductor of one of the pair of electric contacts is made into a specific shape, so that the arc at the time of opening is removed from the power source. To provide a circuit breaker which can prevent wear of contacts and can adjust commutation by disposing an arc runner that moves to the side on the conductor and setting it so that it can move forward and backward with respect to the arc generation source. It is an object.

[Embodiments of the invention]

FIGS. 5 and 6 show an example of a circuit breaker according to the present invention, and the same parts as in FIGS. 1 to 4 are given the same reference numerals, and the explanation thereof will be omitted.

In the same figure, Q51) is a fixed contactor, a fixed conductor←wire, and a fixed contact (consisting of 6 pins.The above fixed conductor is also 2
The distal end side (520) of the U-shaped distal end (520) is bent into a substantially U-shape.
The tip of the contact fixing piece (521) extends horizontally toward the power source side.

Q is a plate-shaped arc runner screwed onto the base end side (521) of the fixed conductor QA with a screw body, etc., and the contact point is <0.
), (the arc that occurred between 97 and 97) is transferred to the full power supply side. The bag has a 6D screw body through-hole formed in the arc runner (goods) and passing through the screw body (goods).
, consists of a long hole extending in the longitudinal direction of the fixed conductor (a), which allows the arc runner Q to move along the arc cQ.
It is set to be slidable so that it can move forward and backward with respect to the generation source side, specifically, the fixed contact (6).

←Q is a screw hole formed in the fixed conductor ←4.

＠ is a pressure reflector made of a high-resistance material having a high resistivity as well as the above-mentioned fixed conductor, and is fixed to the above-mentioned fixed conductor QIJ so as to cover the surrounding area of the fixed conductor G contacts. . Examples of the high-resistance material include organic or inorganic insulators, nickel, and iron.

It is provided by methods such as coating with high-resistance metal such as copper nickel, copper manganese, iron nickel, and iron chromium, coating with thermal spraying, or fixing the molded product. As shown in FIG. 7, the movable conductor (8) is provided with a pressure reflector (a) having the same structure as above.

Next, the operation of the above configuration will be explained.

The opening/closing operation itself by the fixed and movable contacts Qυ, (7) is the same as the conventional one, and the explanation will be omitted.

With the opening operation of the movable contact (7), the contact (
An arc 64 is generated between 6) and (9) as shown in FIG. 7(A), and this arc 64 begins to be drawn and expanded by the magnetic force of the arc-extinguishing plate α force. Now, when the arc runner is set at the position shown in FIG. 7(A), the tip (530) of the arc runner Q is heated to the point where the arc 6 is broken. For this reason, the foot of the arc) does not easily move from the arc 0 to the tip (320) side, but in the middle of the opening period, the arc 0'';4 quickly moves to the arc runner 63, and the It is then expanded further, and at the current zero point, the arc voltage rises and the arc is extinguished.

When the arc relay 4 is transferred from the arc runner to the arc runner, the shape of the fixed conductor is such that the arc current does not flow to the fixed contact (6), and the arc current can quickly transfer to the arc runner side. ) etc. is suppressed as much as possible. Moreover, since the arcs r and 3a are easily transferred to the arc runner and are greatly expanded, the breaking performance is also improved.

On the other hand, at the beginning of contact opening, the vertical piece (520'
b) When a current flows in the direction of the arrow in Fig. 6,
An initial current limit is obtained, especially when the pressure reflector 6″I), (to)
Coupled with the arc squeezing action, the above-mentioned current limiting property is ensured.

When the tip (530) of the arc runner is brought closer to the contact (6) side, the current limiting property is slightly reduced, but on the contrary, the commutation property of the arc CI4 is improved.

That is, if the distance G (Fig. 6) between the tip (530) of the arc runner 6 and the contact (6) is adjusted and the arc runner (II) is set, the current limiting property will not deteriorate.
This has the advantage of ensuring excellent commutation effects.

By the way, in the above embodiment, the arc runner is attached to the base end (521) of the fixed conductor shape, but if the fixed contact (6λ) in the fixed conductor G is also on the power supply side in the direction of the electric path, For example, the same effect as above can be achieved by attaching it to the power supply side vertical piece (5201) of the approximately U-shaped tip (520) and allowing it to slide vertically. .

Furthermore, even if the tip end of the fixed conductor (5) is simply formed into a 5-shape, the same effect can be expected in combination with the arc runner so.

〔Effect of the invention〕

As described above, in the present invention, the tip of the conductor of one of a pair of electric contacts is made into a specific shape, and the arc runner disposed thereon is movable toward and away from the arc source. This setting has the effect of not only preventing contact wear and tear but also achieving a good balance between current limiting and commutation properties.

[Brief explanation of drawings]

Figures 1 to 3 are cross-sectional views of a conventional circuit breaker in different operating states, and Figures 4 (A) and (B) are perspective views of a fixed contact with an arc runner in the conventional circuit breaker, respectively. 5 and 6 are circuit diagrams according to the present invention. An exploded perspective view and a sectional view showing a fixed contact incorporated in an example of +B, FIGS. 7(A) and 7(B) are explanatory diagrams of the operation of the 1qr device in the same circuit, and FIG. 8 is an illustration of the main part of the present invention. Showing a modified example -
It is an r-plane view. (3)...Container, (6), (9J...Contact, (
7), G5υ...electric contact, (11), ?
i force...conductor, a→...arc extinguishing plate, ci group...arc, so...arc runner, (520a)...load side vertical piece. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Masuo Oiwa Figure 1 2 Figure 2 2 Figure 3 2 Figure 4 (A) (B) Figure 5 Figure 6 KotJ Figure 7 (A) CB) Figure 8 Procedural Amendment ( (Voluntary) Commissioner of the Japan Patent Office 1, Indication of the case, Japanese Patent Application No. 156695/1982, 2, Name of the invention, circuit breaker 3, To Katayuni, representative of the person making the amendment, Department 4, Attorney 5, Statement of the specification to be amended. “Claims” column. 6. Contents of amendment A. Description: (1) The scope of claims will be amended as shown in the attached sheet. Scope of Claims after Paper Amendment

Claims (1)

[Claims] <1) At least one pair of electrical contacts that are configured with a conductor and contacts fixed thereto and that open and close within the container, and extinguish the arc that occurs between the contacts when the electrical contacts open and close. a plurality of arc-extinguishing plates disposed in the container, and a vertical piece that extends the tip side of the conductor of one of the pair of electric contacts to the contact fixing position. The arc scanner, which transfers the arc generated during the opening/closing operation from the contact to the power source side, is located on the power source side in the direction of the electric circuit from the contact point of the one conductor, and the arc source A circuit breaker installed so that it can move forward and backward from the side.