JPH0474814B2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to an arc extinguishing device for a wire cutter for wiring, and the present invention relates to a plurality of arc extinguishing grids arranged in tandem in a stepped manner to extinguish arcs in sections. and an arc transfer guide running plate formed by extending the upper end of the fixed contact base to which the fixed contact is fixed, and the extended end plate of the arc transfer guide running plate is arranged vertically outside the arc extinguishing grid. The arc extinguishing device is arranged such that the traveling plate for the arc transfer guide is arranged to obliquely traverse the inside of the ∧-shaped portion of the arc extinguishing grid arranged in tandem in a stepped manner.

[Technical background of the invention and its problems]

This type of arc extinguishing device is composed of a pair of arc running plates 31 and 32 arranged oppositely, and a plurality of arc extinguishing grids 33 arranged between the arc running plates, as shown in FIG. The arc that sometimes occurs between the contacts 34 and 35 is transferred to the arc traveling plate by the magnetic driving force obtained from the arc current, and
The arc was extinguished by guiding it to an arc extinguishing grid, but in the early stages of arc travel, the arc driving force due to the magnetic action of the crid is weak, so the speed of arc travel is slow, and the arc is split within the arc extinguishing grid block. The problem was that it took a long time to generate a high arc voltage, the arc extinguishing current limiting effect was halved, and contact wear was large.

[Purpose of the invention]

As shown in FIGS. 1 to 5, the present invention includes an arc transfer guide running plate that is inclined across the ∧-shaped part of the arc extinguishing grid to transfer the arc generated at the time of contact opening to the running plate. The synergistic effect of the magnetic driving force obtained from the current and the arc attraction force caused by the magnetic action of the arc extinguishing grid allows the arc to quickly move from the contact to the arc extinguishing grid, reducing contact wear and current limiting. The purpose is to provide an arc extinguishing device with improved performance.

[Embodiments of the invention]

An embodiment of the present invention is shown in FIGS. 1 to 5.
The present invention will be specifically explained based on embodiments shown in the drawings. In FIGS. 1 to 5, an opening/closing mechanism is arranged in the center, and a contact part, an arc extinguisher, and a tripping element are arranged on both sides of the opening/closing mechanism, and on the load side. A handle 3 is disposed at the upper center of the insulating cover 2, and as the handle is turned on and off, the crossbar 4 moves up and down in the direction of the arrow shown.

Reference numeral 5 denotes a movable contact base, the base end 6 of which is supported by a support end 7 formed inside the insulating base 1, and is always urged upward by a spring 8.

9 is a movable contact; 10 is an arc travel plate mounted perpendicularly to the movable contact plate at the tip of the movable contact base;
11 is a fixed contact; 12 is a U-shaped fixed contact stand, which has a U-shaped bent end surface 13;

Reference numeral 14 denotes a running plate for arc transfer guide, one of which is attached to the bent end surface 13 of the fixed contact base 12, and moves the fixed contact 1 diagonally upward with respect to the fixed contact fixing surface.
1, that is, as the movable contact opens from the fixed contact and the distance between the fixed contact and the movable contact increases, the distance between the movable contact and the ∧-shaped 14' also increases. The ∧-shaped portion 14' of the traveling plate for arc transfer guide and the fixed contact 11 of the ∧-shaped portion 14' are arranged so as to be approximately equidistant from each other.
It has an extended end plate 15 formed perpendicularly to the fixed contact fixing surface 13 on a side different from the fixed contact fixing surface 13 .

16 is a power terminal metal fitting, and 17 is a power supply side terminal screw.

Reference numeral 18 denotes a plurality of extinguishing grids, which connect the movable contact 1
Corresponding to the locus of the arc traveling plate 10 due to the opening of the electrode 1, a ∧-shaped part 18' of the arc extinguishing grid is provided in a stepped manner.
The extended end plate 15 of the arc transfer guide running plate and the arc running plate 10 fixed perpendicularly to the movable contact base at the time of contact opening are arranged in a vertical line so as to be substantially parallel to each other, and the steps of the arc extinguishing grid are The ∧-shaped portion 18' is arranged so that the ∧-shaped portion 14' of the arc transfer guide running plate crosses the arc-shaped portion 18' at an angle.

Reference numeral 19 denotes an extended end of one of the plurality of extinguishing grids, which is fitted into a groove 20 formed inside the insulating base. Reference numeral 21 denotes an insulating support plate to which the extinguishing grids are vertically fixed from both sides.

Reference numeral 22 denotes a flexible conductor wire with one end fixed to the movable contact base and the other end fixed near the free end of the bimetal 23. Reference numeral 24 denotes an actuating plate having a locking end 25 facing the free end of the bimetal, and the free end 26 of the bimetal bending in response to overcurrent or short circuit current.
is configured to drive the locking end 25 to release a trip latch of the opening/closing mechanism (not shown).

27 is a load terminal plate to which the bimetal is fixed;
8 is a load terminal fitting, and 29 is a load terminal screw.

Furthermore, FIG. 4 shows a traveling plate 30 for arc transfer guide.
This is another embodiment of the structure in which the end face A of the arc transfer guide is press punched, made into a curved shape, and bent into an L shape.

The present invention is constructed as described above, and its functions and effects will now be described in detail.

1 to 5, when a short circuit accident occurs with the handle 3 in the ON state, the bimetal 23, which is rapidly heated by the short circuit overcurrent, curves and the free end 26 engages the locking end 25 of the actuating plate 24. Although not shown in the drawings, the tripping latch of the opening/closing mechanism is released by pressing.

By this tripping of the engagement, the opening/closing mechanism is interlocked, and the cross bar 4 is rapidly driven upward in the figure, and the movable contact block 5 is biased by the spring 8 and operates upward, causing the fixed contact 11 to move from the fixed contact 11 to the movable contact. 9 opens and opens.

The arc generated between both contacts due to this opening is an arc formed with a cross section of Shifting to the base end of the traveling plate 14 for the transfer guide, the ∧-shaped portion of the traveling plate for the arc transfer guide is located between the ∧-shaped portion 14' and the movable contact 9 along the movement of the movable contact and opening, as described above. Since the arc is disposed approximately at the same distance between the fixed contact 11 and the movable contact 9, the arc quickly moves from the contact to the grit side along the ∧-shaped portion of the arc transfer guide traveling plate.

Further, the ∧-shaped portion 14' of the arc transfer guide traveling plate is a ∧-shaped portion of an arc extinguishing grid arranged in a stepwise manner along the locus of the moving arc traveling plate along the opening movement of the movable contact. 18', the arc is quickly traversed by the driving force generated between the conductors of the fixed contact block and the movable contact block, and by the attractive force caused by the magnetic action of the arc extinguishing device consisting of a plurality of grids 18. The arc is guided into the arc extinguishing grid device and divided into multiple arc extinguishing grids to increase the arc voltage, enhance the current limiting effect, and prevent wear of the contacts, thereby extremely smoothing the arc current. This is a serious matter.

Furthermore, in the other embodiment shown in FIG. 4, the arc transfer guide traveling plate 30 is curved into an L shape, and the arc transfer guide end surface A has a curved plate thickness end surface so that the arc transfer travel is extremely easy. As described above, the formed structure allows the initial arc to elongate and transfer extremely quickly.

As described above, the present invention provides an arc transfer guide which is formed by extending the upper end of a U-shaped fixed contact stand to which a plurality of arc extinguishing grids are arranged in tandem in a stepwise manner to divide and extinguish an arc, and a fixed contact is fixed. Equipped with a running board,
The extended end plates of the arc transfer guide running plates are arranged in a row on the outside of the arc extinguishing grid, and the arc transfer guide running plates slope across the inside of the ∧-shaped part of the arc extinguishing grid arranged in a stepwise manner. Because the arc extinguishing device is arranged to Since the arc can be quickly extended and transferred from the contact point, it is possible to prevent wear of the contact and deterioration of the insulation around the contact.Furthermore, the arc can be quickly transferred to the extinguishing grid, dividing the arc and increasing the arc voltage. In order to enhance the current limiting effect, it is possible to shorten the short-circuiting time and stabilize the short-circuit performance, which is extremely effective.

[Brief explanation of drawings]

FIG. 1 is a cutaway sectional view of one embodiment of the present invention, and FIG.
The figure is a sectional view of the main part of the present invention, FIG. 3 is a perspective view of the main part,
FIG. 4 is a cross-sectional perspective view of a main part of another embodiment of the present invention;
FIG. 5 is a plan assembly view of the arc extinguishing grid, and FIG. 6 is a sectional view of a main part of a conventional embodiment. 1...Insulator stand, 2...Insulation cover, 3...Handle, 4...Cross bar, 5...Movable contact stand,
6... Base end of the movable contact plate, 7... Supporting end, 8...
Spring, 9... Movable contact, 10... Arc travel plate,
11...Fixed contact, 12...Fixed contact stand, 13...
... U-shaped bent end surface, 14... Running plate for arc transfer guide, 14'... ∧ of running plate for arc transfer guide
15... Extension end plate, 16... Power supply side terminal fitting, 17... Power supply side terminal screw, 18... Arc extinguishing grid, 18'... ∧ shaped part of arc extinguishing grid, 19...
... Extended end of arc extinguishing grid, 20 ... Concave groove, 21
... Insulating support plate, 22 ... Flexible conductor, 23 ... Bimetal, 24 ... Actuation plate, 25 ... Locking end, 2
6... Free end of bimetal, 27... Load terminal plate, 28... Load terminal fitting, 29... Load terminal screw.

Claims (1)

[Claims] 1. To the upper end of the U-shaped fixed contact base to which the fixed contact is fixed, a ∧-shaped part that moves diagonally upward and away from the fixed contact with respect to the fixed contact fixing surface, and the ∧-shaped part an arc transfer guide traveling plate having an extension plate formed perpendicular to the fixed contact fixing surface on a side different from the fixed contact; An arc traveling plate is fixed perpendicularly to the movable contact plate, and a stepwise pattern ∧ corresponds to the trajectory of the arc traveling plate due to the opening of the movable contact.
A plurality of arc extinguishing grids provided with shaped portions are arranged in tandem so as to be substantially parallel between the extension plate of the arc transfer guide traveling plate and the arc traveling plate fixed perpendicularly to the movable contact. 1. An arc extinguishing device for a wiring sheath breaker, characterized in that the ∧-shaped portion of the arc transfer guide running plate is arranged to traverse the step-like ∧-shaped portion of the arc grid at an angle. 2. The plurality of extinction grids arranged in a column are
The electrode is fixed by a pair of insulating support plates, and one of the plurality of electrode extinguishing grids is formed inside the insulating base with the lower end of the ∧-shaped part of the electrode extinguishing grid straddling the running plate for the arc transfer guide. The arc extinguisher according to claim 1, wherein the arc extinguisher is fixed to an insulating base by fitting into the groove. 3 The arc transfer guide traveling plate has a cross section of L.
The arc extinguishing device according to claim 1 or 2, characterized in that the arc transfer end surface A is curved.