JPS60230321A - Arc extinguisher for electric switch - Google Patents

Abstract

The invention relates to an extinguishing device for power and line protective circuit breakers, consisting of an antechamber located in the circuit breaker housing and an extinguishing laminant stack connected thereto, the antechamber having two lateral antechamber plates used for guiding and limiting the arc, the antechamber plates (25) being produced connected to one another in one piece by means of two crossbars (28, 29, 30), and being inserted as an antechamber block (26) in the antechamber (24). <IMAGE>

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention consists of a front chamber in a switchdex and a stack of arc-extinguishing plates connected thereto. The present invention relates to an arc extinguishing device for electrical switches, particularly power switches and automatic circuit breakers, having a front chamber side plate.

[Technical background of the invention]

In order to avoid damage to the contact piece caused by an arc occurring when the electrical circuit is opened, i.e. when the contact piece is cut, especially at high current intensities, measures have traditionally been taken to remove and extinguish the arc as quickly as possible. It is being

One end of the pivotable contact piece is rotatably supported on one of the two arc conductor plates of the arc extinguishing plate row, and is directly connected to the end of the other arc conductor plate, which is configured as a fixed contact piece and an electrical connection point. A high power cut-off section having an array of arc-extinguishing plates in an arc-extinguishing chamber, carrying electrical contacts at opposite free ends, is disclosed in West German Patent Application No. 24
It is known from specification No. 23207. The base point of the interrupting arc that occurs when the interrupting section is opened moves along the movable contact piece, reaches the rotational support of the movable contact piece on one of the arc guide plates, and then passes through the two arc conductor plates and reaches the end face. It wraps around the arc extinguishing board row from the side. Since a magnetic field is generated when the contact piece is cut, one base point of the ignited interrupting arc rests on the rotating contact piece and is driven toward the fulcrum to one of the arc guide plates in the arc extinguishing plate row. , the other base point of the arc remains in the area of the fixed contact of the other arc guide plate. As soon as the arc has extended to the full height of the arc-extinguishing plate array, it enters the arc-extinguishing plate array and is divided into a suitable number of partial arcs, where it is sufficiently cooled and deionized.

Another solution for the extinguishment of interrupting arcs is disclosed in West German Patent Application Publication No. 27, the subject of which is a current-limiting automatic circuit breaker with arc extinguishing device.
It is known from specification No. 16619. One of the insulating plates that protect the sides of the contact mechanism is made of ceramic, and the other is made of gas-emitting material with a pig insert. The insulating plate is arranged in such a way that the force component resulting from the stray magnetic field emanating from the tripping coil and acting on the arc generated during opening of the contact is directed to the insulating plate having the insert.

If the current reverses, the direction of the magnetic field also reverses, so the above forces always have the same direction. The arc-attracting force of the plane insert of the insulating plate also acts in the same direction. In this way, a sufficient but not too strong outgassing is obtained in a self-regulating manner for cooling the arc. Because the forces are mutually opposed, the arc is symmetrical, resulting in higher travel speeds and avoiding asymmetrical contact burnout.

A West German patent application has been filed for an arc extinguishing chamber for electrical wiring equipment, especially for automatic circuit breakers, which has an arc extinguishing plate assigned to each contact part and a floor plate member surrounded by an insulating material on both sides of each contact part. Publication No. 30
It is known from specification No. 30429. This structure, on the one hand, improves the magnetic blowing of the arc, so that the arc leaves the contact part more quickly and enters the arc extinguishing plate, resulting in an improved breaking process, and on the other hand, the U-shaped insulating curved piece Alternatively, there is an advantage that an auxiliary arc extinguishing effect can be obtained by releasing gas from the insulating material. As a result of good arc blowout, another advantage is obtained by protecting the contacts from burning out. Therefore, the precious metal coating on the contact piece can be reduced.

The above-mentioned arc extinguishing device, which operates using the forced arc extinguishing method, consists of a front chamber that constricts the arc to an appropriate length, and a stack of arc extinguishing plates that is connected to this and divides the arc into partial arcs. It is preferable that To form the vestibule, intercalated metal fittings or plates of ceramic, plastic or gas-releasing material are often used. It is preferable to support this type of element from the outside by suitably shaping the walls of the dex. The inside of the vestibule is usually obtained by suitably arranging the arc displacement rods.

[Problems with background technology]

Considering the number and dimensions of the installed parts, the compact construction of circuit breakers and the trend towards further reduction in dimensions,
The drawbacks are clear. Assembling a large number of small parts is tedious and time consuming.

When constructing the arc moving rod, its isolation function must be considered. In order to fix the position of the insert, each half of the cutlet must have a different fulcrum.

[Purpose of the invention]

SUMMARY OF THE INVENTION The object of the present invention is to provide an arc extinguishing device for an electric switch which avoids the above-mentioned drawbacks, simplifies the assembly of the front chamber, and improves functionality.

[Summary of the invention]

According to the invention, the vestibule plate realizing the lateral restriction of the vestibule is made of injection or pouring material, the two plates being connected to each other by at least two crossbars so as to form a single piece. It is installed inside the front room as a front room block. A preferred improvement is to provide a projection on the front chamber rim, which is used for positioning the switch in the box, so that the switch can omit an auxiliary fulcrum in the box.

As a result, it is particularly cost advantageous for the manufacture of switch boxes or their breath dies.

A further improvement is obtained if the switch is provided with a recess in the box, and the protrusion projecting on the front chamber block engages in this recess for fixing the front chamber block.

As an alternative, the switch box can also be provided with a recess for receiving a front chamber protrusion configured as a resilient snap element. To ensure secure fixation during the assembly process,
You can also repeat and tighten the prongs from the outside. In a preferred embodiment of the one-piece vestibule block, the vestibule block is made of thermoplastic glass, and in order to rigidly fix it to the vestibule, protruding protrusions pass through the wall of the dex, and the outside It is then deformed into a rivet shape by a thermal plunger. This construction requires only a single component, which is advantageous to manufacture and much easier to handle during assembly of the circuit breaker. The above-mentioned horizontal bar that connects the two front chamber plates to each other is preferably arranged as follows. One horizontal bar is located above or behind the arc transition point, that is, the place where the base point of the arc moves or transfers from the tip of the contact to the arc conductor bar, and one or more horizontal bars are located in front of the arc extinguishing plate row. It is done so that it is as follows. The advantage thereby obtained is that the crossbar behind the transition point enlarges the gas emission surface behind the arc. When the arc is divided into individual arcs by the arc-extinguishing plate row, one or more transverse bars in front of the arc-extinguishing plate row prevent the prechamber area from being re-ignited.

This is because the arc is rapidly deionized by the horizontal bar. The gas release effect of the front chamber plate is greatly promoted by one horizontal bar and even affects the metal plate pieces of one arc extinguishing plate stack. The partial arc is thus kept more stable between the arc-extinguishing plates. As soon as the partial arc is re-ignited in the sheet metal piece, the outgassing action of the crossbar begins, and the arc is accelerated and driven into the stack of arc-extinguishing plates, where it is split again. At the same time, the crossbar prevents the restriked arc from entering the prechamber. The number of crossbars depends on the interrupting power in question and the associated arc energy.

Other preferred embodiments and refinements of the invention are shown in the dependent frames. The invention, preferred embodiments, improvements and other advantages thereof will be explained and described in detail on the basis of the drawings which show examples of the invention.

[Embodiments of the invention]

In the contact mechanism shown in FIG. 1, a movable contact piece 10 is rotatably supported at a rotation center 7J in a box (not shown in detail). The rectangular contact 12 contacts a fixed contact piece 14 coupled to an arc guide rod 16 . The arc guiding rod 16 is the upper boundary of the arc extinguishing chamber 18 that accommodates the arc extinguishing plate stack 20.

The lower side of the arc extinguishing chamber 18 is defined by an arc guiding rod 22 . The arc guiding rod 22 defines the side and lower side of the front chamber 24 which is directly connected to the arc extinguishing chamber. A front chamber block 26 configured according to the present invention is installed inside the front chamber 24 defined by the stack of arc-extinguishing plates 20 and the arc guiding rod 22.

A horizontal bar 28 is installed on the back side of the front chamber protrusion 26, facing the contact portion between the rectangular contact 12 of the movable contact piece 10 and the fixed contact piece J4.
Below this contact portion, the side walls of the front chamber block are rigidly connected to each other by two horizontal bars 30.

A structure similar to that shown in FIG. 1 is shown in FIG. Unlike Fig. 1, the contact part is not shown in detail, but the fulcrum 1 in the box is
The rectangular contact J2 of the movable contact piece 10 is rotatably fixed to
It is between 3 and 3. Therefore, other structures have been slightly modified. An arc conductor rod 22 is connected to the fixed contact piece 23 and defines the side and lower side of the front chamber 24 together with the front chamber block 27 and the arc extinguishing chamber 18 installed therein. The upper part of the arc extinguishing room is specified by the arc guide rod 17
carried out by The front chamber block 27 has a square contact 12
A horizontal bar 28 is provided at the height of the contact portion between the fixed contact piece 230 and the fixed contact piece 230.

Below the horizontal bar 28, three horizontal bars 3J are arranged immediately in front of the stack of arc-extinguishing plates 20.

FIG. 3 shows a side view of the anterior chamber block. The cross bar 28 facing the contact area and the transition point has a rectangular cross section, and the cross bar 30 in front of the stack of arc-extinguishing plates has a circular cross section. The outer shape of the front chamber 26 resembles the outline of a box. The side surface 25 of the front chamber block 26 containing the transition point is a rectangular cavity 32
A hypotenuse 34 is provided on the diagonally opposite side and contacts the arc guiding rod 22 that matches the outline of the box. In this case, the movable contact piece 10. Fixed contact piece J4 and arc guide rod 22
The shape of the cavity was selected so that the front chamber block 26 could be attached even if the front chamber block 26 (as shown in FIG. 1) had already been assembled.

2 connected to each other by one horizontal bar 28 and three horizontal bars 30
A front view of the front chamber block 26 having two front chamber plates 26 is shown in FIG.

FIG. 5 shows a side view of a vestibule 26 having a rectangular cavity 32 and a hypotenuse 34 according to FIG. The transverse bar 29 next to the transition point has a triangular cross section. Rectangular cavity 32
Below, in the forward area of the arc-extinguishing plate stack 20 in the mounted state, there is a horizontal bar 30 of circular cross section.

FIG. 6 shows a front view of the above-mentioned front chamber block, which is made up of two front chamber plates 25 connected to each other by a horizontal bar 29 and a horizontal bar 30.

FIG. 7 shows a plan view of the front chamber block 26.

In the front chamber plate 25 connected to each other by the horizontal bar 28 and the horizontal bar 30,
Four protrusions 36 are provided in a protruding manner, and are passed through a cavity 42 arranged correspondingly to the side wall 40 of the box to fix the front chamber 26.

FIG. 8 also shows a plan view of the front chamber block 26.

In this case, four protrusions 36 are provided in a protruding manner on the front chamber plate 25 which is connected to each other by the horizontal bars 28 and 3o, and pass through the hollow part 44 of the wall 4o of the box. For fixing the front chamber protrusion, the protrusion 37 is fixed from the outside to the wall 40 of the box by means of rivets 38.

FIG. 9 shows a partial view of the snap joint of the front chamber connector 26 in the box. A pin 46 fixed to the front chamber plate 25 and cut in the longitudinal direction from the end face has a raised thickened portion 48 directly at its free end. When the front chamber part 26 is installed inside the switch box, the thickened part 48 of the core engages with the appropriately formed cavity 517 in a secure and restraining manner, and at that time,
Due to the notch 52 in the pin 46, its end is radially compressed and resumes its original position when the load is removed.

The functions of the integrated vestibule pro 26.27 are as follows. That is, when the movable contact piece 10 separates from the fixed contact piece J4.23, an arc is ignited, but the side part is restricted by the front chamber plate 25, and from the fixed contact piece J4e23, the arc guiding rod 16° J7 and Arc-extinguishing plate stack 2 arranged between 22
Move to 0. The horizontal bars 2B' and 29 accelerate the arc and drive it to the stack of arc-extinguishing plates by the gas release action, thereby contributing to extinguishing the arc there.

In this case, the horizontal bar 28 behind the transition point is the arc-extinguishing plate stack 20
It is configured to have a much larger gas discharge surface than the horizontal bar 30 in front of. As a result, the gas discharge surface on the rear side of the arc is many times larger, so that the arc travel speed is not adversely affected by the crossbar 30 in front of the stack of arc-extinguishing plates 20. Next, when the arc is in the stack of arc-extinguishing plates 20 and is divided into individual arcs, it is transferred from the arc-extinguishing chamber 18 to the front chamber 2.
4 is weak, the side bar or bars 30 prevents re-ignition in the front chamber 24 by the gas release action.

With particular reference to FIG.
The primary mission is to isolate the

The gas release surface is the surface of the front chamber plate 25. That is, the arc energy is mostly converted into decomposition energy in the prechamber area.

The horizontal rods 28 and 29 are arranged so that the arc movement speed is increased after the transition of the arc base point from the movable contact piece JO to the arc guiding rod 16 or 22 by bringing the horizontal rods 28 or 29 as close as possible above the transition point. It is even more advantageous to configure.

The crossbar 30, which has the same primary mission as the crossbar 28.29,
It has the basic disadvantage of reducing arc travel speed. However, the crossbar 30 is arranged at the end of the front chamber plate (seen in the direction of arc movement), so that the gas discharge surface behind this crossbar by the front chamber plate 25 is directly located on the front chamber plate in the area of this crossbar. Since the gas ejection surface of the face and cross bar surface is much larger, the driving force on the arc is much greater than the restraining action of the cross bar 30, so that the arc movement speed is virtually not adversely affected.

〔Effect of the invention〕

According to this invention, it is possible to simplify the assembly and improve the arc extinguishing function.

[Brief explanation of drawings]

FIG. 1 is a side view of a conventional contact mechanism of a circuit breaker having a front chamber in which an arc extinguishing chamber and a front chamber block according to the present invention are installed, and FIG. 2 is a side view of a conventional contact mechanism of a circuit breaker having an arc extinguishing chamber and a front chamber block according to the present invention. A side view of a conventional contact mechanism having a front chamber with a built-in front chamber (arrangement of movable contact pieces changed from FIG. 1); FIG. 3 shows a side view of a front chamber block with three horizontal bars. Fig. 4 is a front view of Fig. 3, Fig. 5 is a side view of the front chamber block provided in Fig. 1 with one horizontal bar, Fig. 6 is a front view of Fig. 5, Figure 7 is a plan view of the front chamber protrusion, which is attached to the box and the protrusion engages with the hollow part on the box side. FIG. 9 is a partial view of the vestibule block having snap members as protrusions. 24... Front chamber, 25... Front chamber plate, 26... Front chamber block, 28... Horizontal bar, 29... Horizontal bar, 30...
Horizontal bar.

Claims (1)

[Claims] 1) The switch consists of a front chamber located in the box and a stack of arc extinguishing plates connected thereto, and the front chamber has a front chamber side plate for guiding and restricting the arc. In the arc extinguishing device for a power switch and an automatic circuit breaker, the front chamber plate (25) is connected to each other by at least two horizontal bars (28m29*3') and is made integrally, and is used as a front chamber block (26). Antechamber (2
4) An arc extinguishing device characterized by being installed inside the arc extinguishing device. 2) The protrusion (36) protruding from the front chamber protrusion (26) is used for positioning the switch within the box, and therefore the corresponding fulcrum is not located within the box. An arc extinguishing device according to claim 1. 3) The front chamber block (26) is injected or ejected - f4
The arc extinguishing device according to claim 1 or 2, wherein the arc extinguisher also plows hφIh=r-reduction 1--1->'L. 4) The front chamber block (26) can be fixed by fitting the protrusion (36) into the corresponding cavity (42) in the switchdex. The arc extinguishing device according to any one of ranges 1 to 3. 5) Sui, chi? , a hollow part (44) is provided in the wall of the box,
In order to position the anterior chamber protrusion (26), its protrusion (3
The arc extinguishing device according to any one of claims 1 to 4, wherein the arc extinguisher (6) passes through the cavity (44). 6) The protrusion (36) protruding from the front chamber is configured as an elastic snap member, and the hollow part (44) in the wall of the switch
) The arc extinguishing device according to any one of claims 1 to 5, wherein the arc extinguishing device is locked to the arc extinguisher according to any one of claims 1 to 5. 7) The arc extinguishing device according to any one of claims 1 to 6, characterized in that the front chamber block (26) can be fixed to the switchdex with rivets, screws, or pin joints. 8) The arc extinguishing device according to any one of claims 1 to 7, wherein the fixing portion provided for fixing is accessible from the outside. 9) Horizontal bar (2) provided for connecting the front chamber plate (25)
8, 29, 30), the first horizontal bar (28, 29) is located above or behind the arc transition point on one side or on a plurality of second horizontal bars (28, 29).
The arc extinguishing device according to any one of claims 1 to 8, characterized in that the horizontal bar (30) is disposed in front of the stack of arc extinguishing plates (20). . 10) The extinguisher according to any one of claims 1 to 9, characterized in that the horizontal bars (28, 29, 30) are configured to emit gas when an arc occurs. arc device.