JPS6054131A - 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 the Invention] This invention relates to a circuit breaker having a pair of electrical contacts.

[Prior Art] Conventionally, there have been circuit breakers of this type as shown in FIGS. 1 to 3. In FIG. 1, (1) is a cover, (2) is a base, and the cover (1) and the base (2) constitute a case (3). (4) is a fixed contact, which has a fixed conductor (5), has a fixed contact (6) at one end, and has a terminal portion at the other end to be connected to an external conductor (not shown). ing. (7) is a movable contact, which has a movable conductor (8), and has at one end a movable contact (9) facing the fixed contact (8). (10) is a movable contact device, and (11) is a movable arm that is fixed to a crossbar (12) and is configured to be opened and closed when each pole is spaced. The fixed contact (4) and the movable contact (7) form approximately 14+7 wires when closed, resulting in a so-called butting electrode arrangement. (13) is an arc extinguishing chamber in which an arc extinguishing plate (14) is held by a side plate (15). (16) is a toggle link mechanism composed of an upper link (17) and a lower link (18). One end of the upper link (17) is Freddle (
18), and the other end is connected to one end of the lower link (18) by respective shafts (20) and 2'1).

The other end of the lower link (18) is connected to the movable contact device (
10) is connected to the movable arm (11). (22)
(23) is an operating spring that connects the shaft (21) of the toggle link mechanism (16) with the operating handle (2).
2). (24) and (25) are thermal and electromagnetic trip mechanisms, respectively, and when activated, the tripper (28) is rotated counterclockwise by a bimetal (2G) and a movable iron core (27), respectively. . (29) has one end connected to the above tripper (2
8), and the other end is a latch that is locked to the fredle (19). When the operating handle (22) is tilted to the closing position with the fredle (18) locked in the latch (29), the toggle link mechanism (16) is extended and the shaft (21) is engaged with the fredle (19). The movable contact (9) is joined to the fixed contact (8). This state is shown in FIG.

Next, when the operation handle (22) is tilted to the open position, the toggle link mechanism (16) is bent to separate the movable contact (9) from the fixed contact (6) and move the movable arm (11) to the fredl shaft (30). is locked. This state is shown in FIG. Also, if an overcurrent flows through the circuit in the closed circuit state shown in Figure 1 above,
The thermal tripping mechanism (24) or the electromagnetic tripping mechanism (25) operates to release the fredle (19) and the latch (23).
) is released, the fredle (18) rotates clockwise around the fredle shaft (30), and the stopper shaft (31)
is locked. Fredl (19) and Kamilink (17)
Since the connection point of the above-mentioned operating spring (23) exceeds the line of action of the above-mentioned operating spring (23), the toggle link mechanism (
16) is bent and each pole is interlocked with each other to perform automatic shutoff by the cross spar (12). This state is shown in FIG.

Next, the behavior of the arc that occurs when the circuit breaker cuts off 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 contact (6), movable contact (9) and movable conductor (8)
) is sequentially supplied to the load side.

In this state, when a short circuit current flows through this circuit, the movable contacts (9) are opened as described above. On this occasion,
There is an arc (
32) occurs, fixed and movable contacts (6), (11)
An arc voltage is generated between them. This arc voltage increases as the separation distance of the movable contact (9) from the fixed contact (6) increases.1. At the same time, the arc (32) is drawn toward the arc-extinguishing plate (14) by the magnetic force and extends, so that it further rises. In this way, the arc current reaches a current zero point and the arc (32) is extinguished, completing the interruption.

According to the above-mentioned conventional circuit breaker, when the circuit breaker is cut off, the contact (
8) The legs of the arc (32) generated between 8) and (9) do not move easily and remain on the contacts (it) and (9) for a long time, resulting in wear and tear on the contacts (8) and (9)'. The disadvantage was that there was a significant Also, arc (32) from contacts (e) and (9)
Since the legs do not move, the cooling effect of the arc-extinguishing plate (14) is insufficient, and the breaking performance at the zero current point is also insufficient, which is particularly an obstacle to increasing the voltage.

[Summary of the invention] This invention was made to solve the above-mentioned drawbacks.
By forming a tip of the movable contact as a protrusion that protrudes in the direction of the fixed contact from the contact point, and forming a recess into which the protrusion fits into a portion of the movable contact that faces the protrusion. It is an object of the present invention to provide a circuit breaker which reduces the wear and tear of the contacts and improves the breaking performance by quickly moving the arc generated between the contacts to other parts of the electrode.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to the drawings.

In Figure 4, the iJf moving contact (9) of the movable conductor (8)
A protrusion (81) protruding in the direction of the fixed conductor (5) is formed at the tip end.
) A recess (51) into which the protrusion (81) fits when the circuit is closed is formed in the upper part of the fixed conductor (5) facing the protrusion (81) (FIG. 5(A)). ) and recess (
51) means the quantity ratio l! of contacts (8) and (9) when opened, as shown in Figure 5 CB). Side surface (51S) of recess (51) and side surface (81S) of protrusion (81) from Ilb 17)
The configuration is such that there is a position where the distance #a is shorter.

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

FIG. 6 shows the movement of the electrode during the shear breakage operation and the movement of the arc (32) accompanying this. When the opening operation starts from the state where the flow is flowing between the contacts (8) and (9) at the time of closing as shown in Fig. 6 (A), an arc (32) is generated between the contacts (6 Figure (B)). Then, when the protrusion (81) and the recess (51) are opened to a position where the distance between the side surfaces (81S) and (51S) is shorter than that between the contact points (8) and (9), as shown in FIG. As shown in (C), an arc (32
) is transposed. Further, the arc (32) approaches the arc extinguishing plate (14) due to the above dislocation, but the arc (32) approaches the arc extinguishing plate (14).
14), it is further attracted to the arc-extinguishing plate (14) (FIG. 6(D)). Therefore, arc (32)
is sufficiently cooled and is reliably cut off at the current zero point. Furthermore, the dislocation of the arc (32) depends on the distance between the contacts (8) and (9), the protrusion (81) and the recess (51).
) becomes equal, so if the distance between the protrusion (81) and the recess (51) is set short,
At the same time as opening, the arc (32) is quickly dislocated,
Wear of the contacts (6) and (11) is also significantly reduced.

In addition, by forming the recess (51) as a through hole as shown in FIG. 7(A) CB), the current I can flow into the fixed contact (6) from the side of the fixed contact (6). Therefore, the negative magnetic influence of the current I on the arc (32) can be reduced, and the dislocation of the arc (32) becomes easier.

[Effects of the Invention] As explained above, according to the present invention, the distal end portion of the movable contact is formed as a protrusion that protrudes in the direction of the fixed contact, and the fixed contact facing the protrusion is formed as a protrusion. By forming a recess into which the protrusion fits into the contact, the arc generated between the contacts is quickly moved to the tip of the movable contact, which reduces contact wear and improves the breaking performance. can be improved.

[Brief explanation of the drawing]

Figures 1 to 3 are cross-sectional views showing conventional circuit breakers. Figure 1 shows the closed circuit state, Figure 2 shows the open circuit state, Figure 3 shows the open circuit state due to tripping operation, and Figure 4 shows the circuit breaker in the open circuit state. FIG. 6 is a perspective view showing a circuit breaker according to an embodiment of the invention, FIG. 5 is a partial sectional view of the same embodiment, FIG. An example is shown in which FIG. 7(A) is a side view and FIG. 7(B) is a plan view. (4)...Fixed contact, (6)...Fixed contact, (7
)...Movable contact, (8)...Movable contact, (5 work)
... recess, (81) ... protrusion. Note that the same reference numerals in the figures indicate the same or corresponding parts. Agent Oiwa Masu〃U Figure 1 Figure 3 Figure 4 Blood Figure 5 Figure 6 Figure 7 Procedure correction sound (i゛1 sound) Mr. Commissioner of the Japan Patent Office 1, Indication of the case Japanese Patent Application No. 161379/1979 2. Title of the invention, circuit breaker 3. Person making the amendment; 6. Contents of amendment A. Description: (1) The scope of claims will be amended as shown in the attached sheet. (2) Page 6, first line; "Movable contact" should be corrected to "fixed contact." Claims as amended above: ``(1) A movable contactor and a fixed contactor each having at least one pair of conductors and a contact fixed to each of the conductors, in which electricity flows through each conductor in the closed state. In a circuit breaker installed so that the directions of the movable contacts are the same and are substantially straight, the tips of the movable contacts are formed as protrusions that protrude in the direction of the fixed contacts. A circuit breaker characterized in that a recess into which the second protruding part fits is formed at a location of the fixed contact facing the part. (2) The circuit breaker according to claim 1, wherein the recess is formed as a through hole passing through the fixed contact. ”

Claims (2)

[Claims] (1) A movable contactor and a fixed contactor each having at least one pair of conductors and a contact fixed to each conductor,
In a circuit breaker installed 1τi so that the direction of electricity flowing through each conductor in the closed state is the same and almost linear, the above IIf! I! The tip of the II contact is formed as a protrusion that protrudes in the direction of the fixed contact from the contact point, and a recess into which the protrusion fits is formed at a portion of the movable contact opposite to this protrusion. Characteristic circuit breaker. (2) The circuit breaker according to claim 1, wherein the recess is formed as a through hole passing through the fixed contact.゛