JPH02239525A - Power switch - Google Patents

Abstract

PURPOSE:To shorten arc shift time to a transfer electrode by enhancing driving and expansion of arc between contacts during the process of opening. CONSTITUTION:As a moveable contact 11 moves in opening direction, the moveable contact opposite portion 22c of a transfer electrode 22 and the moveable contact 11 come near to each other, and arc 23 which is thereby further driven and expanded has its end shifted from a moving contact point 11a to a U-shaped portion 22a and the other end from a fixed contact 13a to an arc runner 13b, and the arc 23 is further driven and expanded by the action of the fixed contact 1 and the arc runner 13b caused by the shift, and is shifted between the B point of the arc runner 13b and the transfer electrode 22. Since the position of the arc 25 shifted is distant from the vertical portion 22d of the transfer electrode 22, the arc 23 is drawn into an arc-extinguishing grid 21 in a short time and operation of cutting off a current is thus completed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a power switching device that opens and closes an electric circuit.

[Prior Art] Figures 6 to 9 are diagrams showing an example of the configuration of a conventional power switchgear disclosed in, for example, Japanese Patent Laid-Open No. 59-191914, and in these figures, (l) is a steel plate. The mounting base is formed with a plurality of mounting holes (1a) that are used when installing the power switchgear main body. (2)
is a base made of insulating material, and is fixed by a mounting base (1) and screws (3).

(4) is a fixed core made of laminated silicon steel plates, on which is attached an operating coil (5), and furthermore, a leaf spring (6) is arranged as a cushioning material in the gap between it and the mounting base (1).

(7) is a movable iron core disposed opposite to the fixed iron core (4), and is adapted to be attracted to the fixed iron core (4) when the operation coil (5) is energized. (8) is a cross bar made of insulating material, which connects the movable iron core (7) via the bin (9).
) is connected. (lO) is a trip spring disposed between the crossbar (8) and the mounting base (1), which normally pushes the crossbar (8) so that the main circuit of the power switchgear is opened. I'm raising it.

(l1) is a movable contact equipped with a movable contact (lla),
It is inserted into a holding hole (8a) provided in the cross bar (8) and is pressurized by a pressure spring (l2). (l3
) is a fixed contact equipped with a movable contact (1l) and a fixed contact (18a) facing the movable contact (lla).
14) to the terminal (l5), and to the base (2) with screws (16) and (17).

(13b) is an arc runner, which is electrically connected to the fixed contact (13) or integrated with the fixed contact (13). (18) is a terminal screw connected to the main circuit electric wire, and is screwed into the terminal (15). (19) is an arc box made of insulating material, which is fixed to the base (2) with screws (20), and includes a hole (19a) for discharging arced gas to the outside, a ceiling part (19b), and a side plate (19c).
). (21) is an arc extinguishing grid made of a magnetic material having a shape as shown in FIG. 9, and (22) is a commutation electrode, which is fixed to the ceiling (19b) of the arc box (19). Further, the fixed contact (lla) and the movable contact (lla) are configured to be accommodated in the internal space of the arc extinguishing chamber (A) as shown in FIG.

Next, the operation will be explained. As shown in Fig. 6, when a voltage is applied to the operating coil (5) while the main circuit is open, magnetic flux is generated between the fixed iron core (4) and the movable iron core (7), and the tripping spring The movable core (7) is attracted to the fixed core (4) against the urging force of (10). At this time, the crossbar (8) connected to the movable iron core (A)
operates in the same way, and the movable contact (ll) of the movable contact (l1)
a) comes into contact with the fixed contact (13a) of the fixed contact (13), and a predetermined pressure is applied by the pressure spring (12) to close the main circuit.

Next, when the fixed core (4) is demagnetized, the movable core (7) is moved from the fixed core (
4), and the crossbar (8) also moves in conjunction with this movable iron core (7). Therefore, the crossbar (8
>> returns to the state shown in Figure 6, and the movable contact (
lia) and the fixed contact (i3a) are separated, and upon this separation, an arc is generated between the movable point (lla) and the fixed contact (13a).

Hereinafter, the process from the generation of the arc to the extinction of the arc will be explained in detail with reference to FIGS. 10(a) to (r).

Figure lO (a) shows the fixed contact (13a) and the movable contact (ll
a) shows the closed state. When the fixed contact (13a) and the movable contact (Ila) are opened while the operating coil (5) is energized, an arc is created between the fixed contact (13a) and the movable contact (Ila) as shown in figure (b). (28) occurs. The contact separation distance increases over time until it reaches a certain distance, and the movable contact (1l) is moved by the current flowing through the fixed contact (l3) and the arc-extinguishing grid (2l) made of a magnetic material, as shown in Figure (C). It is driven and extended like an arc (23), and further transferred from the surface of the fixed contact (13a) to the arc runner (13b) as shown in FIG.

Next, dielectric breakdown occurs between the tip of the arc (23) shown in figure (d) and the part of the arc runner (13b) shown at point (B), and one end of the arc (23) breaks down as shown in figure (e). As shown in the figure ('), the other end of the arc (23) is transferred from the fixed contact (13) to the commutating electrode (22), and the arc (23 ) is attracted between the arc extinguishing grids (2l) and the arc is extinguished, completing the current cutting operation.

[Problems to be Solved by the Invention] In the conventional power switchgear as described above, this is caused by the fact that the distance between the movable contactor (II) and the commutating electrode (22) is wide when the contact is opened. The arc (23) generated between the fixed and movable contacts (13a) and (Ila) is insufficient when the contacts are opened.
3) One end is connected to the commutating electrode (22) from the movable contact (1.1a).
), and the expensive movable contact (lla) wears out more quickly.

This invention was made in order to solve the above-mentioned problems, and by shortening the time required for arc transfer between contacts when opening, it is possible to reduce wear and tear on the movable contacts. The purpose is to obtain a vessel.

[Means to solve the problem]

The power switchgear according to the present invention includes: a fixed contact joined to a fixed contact; an arc runner electrically connected to the fixed contact; a movable contact joined to a movable contact and disposed opposite to the fixed contact; In order to transfer the arc generated between both contacts during the opening process, a commutating electrode is provided, which consists of a protrusion whose top faces the arc runner, and a horizontal portion that is close to the movable contact at least in the upper part of the movable contact; An arc extinguishing grid for drawing in the arc is provided.

[Function] The commutation electrode of the present invention shortens the time required for arc transfer to the commutation electrode by increasing the driving and elongation of the arc between the contacts during the breaking process.

Furthermore, the strength of the magnetic field generated by the current flowing through the commutating electrode at the position of the arc after the transition is suppressed, thereby shortening the time required to draw the transition arc into the arc extinguishing grid.

[Embodiment] A power switchgear according to an embodiment of the present invention is completely the same as the configuration of the mounting base (1) to the arc extinguishing grid (2l) in FIGS. 6 to 9 showing the conventional example, and these Duplicate configuration explanation regarding the part will be omitted.

FIG. 1 shows the essential parts of a power switchgear according to an embodiment of the invention, and is a block diagram of fixed and movable contacts and means for extinguishing an arc generated between them when they are opened. In the figure, (11) is a movable contact to which the movable contact (11.a) is joined, and (l3) is a fixed contact to which the fixed contact (13a) is joined and electrically connected to the arc runner (13b). , (2l) is an arc extinguishing grid, and (22) is a commutation electrode, which is a feature of the present invention, and the top of the protrusion is a U-shaped part (22) facing the arc runner (13b).
a), a movable contact facing part (22b), and a movable contact facing part (22b) formed so as to be close to the tip of the movable contact (11) at the upper limit opening position (the position shown in FIG. 1).
c) and a vertical portion (22d) that connects the movable contact facing portion (22c) and the movable contact facing portion (22b).

As mentioned earlier, in the power switchgear according to the present invention having the above-described configuration, the mounting base (1) to the arc extinguishing grid (21) in the overall configuration are the same as in the conventional example, and their operation is also different. Since the operation is exactly the same as that described with reference to FIGS. 6 to 9 in the conventional example, redundant explanation will be omitted, and the operation will be explained based on the configuration shown in FIG. 1 and with reference to FIG. 2. However, movable and fixed contacts (lla), (13a)
The operations shown in FIGS. 2(a) to (C), which show the opening process from the closed state of
), the explanation of these operations will also be omitted.

As shown in FIG. 2(d), as the movable contact (11) moves in the opening direction, the movable contact facing portion (22c) of the commutation electrode (22) and the movable contact (l1) One end of the arc (23), which is close and thus further driven and extended, is directed from the movable contact (lla) to the U-shaped part (22a), and the other end from the fixed contact (13a) to the arc runner (13b).
), and due to the current flowing through the fixed contact (l3), arc runner (13b) and commutating electrode (22) due to the transfer of this arc (23) and the action of the arc extinguishing grid (2l), the arc (23) ) is further driven and stretched,
B of the arc runner (13b) as shown in Fig. 2(e).
A transposition occurs between the point and the commutating electrode (22). The position of this transposed arc (23) and the vertical part (22d) of the commutating electrode (22)
), the magnetic field generated by the current flowing through the vertical part (22d) has a weak attraction to the arc (23) in the direction of the arrow (C) in the figure.
), the arc (23) is drawn into the arc extinguishing grid (2l) in a short time, and the current interruption operation is completed.

In addition, in the above embodiment, the commutation electrode <22) is the movable contact (
11) was formed as a movable contact facing part (22e) that was close only to the tip of the movable contact (l1), but as shown in Fig. 3, the horizontal part of the commutation electrode (22) The portions may be formed so as to be close to each other over the entire length of the movable contact (l1), in this way, as shown in FIG. 2(e).
The attractive force to the arc (23) shown by the arrow (C) can be reduced to zero, further improving the breaking performance.

In addition, as shown in Fig. 4, the arc runner (13b) does not extend to the side of the arc extinguishing grid (2l), and as shown in Fig. 5, the arc runner (13b) is divided into sections (1
3bl). (lab2) also provides the same effect as the above embodiment.

[Effects of the Invention] As described above, according to the present invention, the shape of the commutation electrode for transferring the arc generated between the contacts when the contacts are opened is such that the movable contact and the commutation electrode are brought close to each other. In addition to increasing the drive and extension of the arc, the arc after transition is easily drawn into the arc extinguishing grid, which shortens the time required for the arc to displace and extinguish, and reduces contact wear. be able to.

[Brief explanation of drawings]

FIG. 1 is a configuration diagram showing the main parts of a power switchgear according to an embodiment of the present invention, FIGS. 2(a) to (r) are explanatory diagrams of the operation of the present invention, and FIGS. 5 is a configuration diagram showing the main parts of another embodiment of the present invention, FIG. 6 is a sectional view showing an example of a conventional power switchgear, FIG. 17 is a side view of FIG. 6, and FIG.
The figure is a plan view of FIG. 6, FIG. 9 is a perspective view of an arc extinguishing grid used in the power switchgear of FIG. 6, and FIG. 10 is an explanatory diagram of the operation of the conventional power switchgear. In the figure, (1-1) is a movable contact, (11&> is a movable contact, (I3) is a fixed contact, (13a) is a fixed contact, (13b) is an arc runner, (21) is an arc extinguishing grid, ( 22) is a commutation electrode, (22a) is a U-shaped part, (
22c) is a movable contact opposing part. Note that the same reference numerals in the figures indicate the same or equivalent parts. Agent Patent Attorney Souji Sasaki 11: Movable contact 11a: 珂vJ窗子13: Fixed contact angle Mushiko 13a: Fixed contact 22C: Possible! j] Entrance dimension Muka Toyoshi 10 diagram (d) (b) fe) fc) (f)

Claims (1)

[Claims] A fixed contact joined to a fixed contact, an arc runner electrically connected to the fixed contact, a movable contact joined to a movable contact and arranged opposite to the fixed contact, and the movable contact is connected to the fixed contact. A protrusion is provided to transfer the arc generated between both contacts during the opening process of the twist, and the protrusion is formed such that the top thereof faces the arc runner, and at least the upper part of the movable contact is close to the movable contact. 1. A power switchgear comprising: a commutating electrode consisting of a horizontal portion formed in a horizontal portion; and an arc extinguishing grid that draws in the arc after the transition.