SK280250B6 - Automatic circuit breaker - Google Patents

Abstract

Circuit breakers are provided inside their insulating material housing (1) with an extinguishing chamber (3) which is divided into the actual arc extinguishing region, generally filled with an arc splitter stack (4), and into a funnel-shape antechamber space (3c), located in front of said region, having the contact arrangement (5). Two webs (3d, 3e), projecting in the opening plane of the contact lever (5b) which can be pivoted, are integrally formed on the inner side surfaces (3a) in the antechamber space (3c), which webs are arranged running closely from the contact arrangement (5) along arc running rails (5a', 6, 7) to the arc splitter stack (4). A plurality of columns (3f), rising from the base of the side surfaces (3a), are arranged distributed approximately evenly between the webs (3d, 3e), which columns, in conjunction with the webs (3d, 3e), result in close lateral guidance of the switching arc (9). The gas pressure produced in front of the wandering arc (9') can be relieved in the flow channels (8) between the columns (3f).

Description

Technical field

BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a self-contained switch mounted in a housing made of insulating material and comprising a contact device and a switching mechanism, having an arc chute in the housing having a pre-chamber space adjacent to the contact device. arc quenching.

BACKGROUND OF THE INVENTION

Such switches with specially adapted arc chambers are known in many embodiments, for example from DE 1 185 269, DE 1 185 274. Known switches comprise inside the insulating material housing a light arc chamber associated with a contact point and equipped with arc quenching plates for efficient arc quenching. switching arc of light produced by short circuit.

Further development of these basic chamber shapes is described in DE 27 16 619 B1,

DE 33 37 562 A1, EP 0 123 090 B1, EP 0 158 124 A2 and EP 0 251 160 A2. All these arc-quenching devices have in common that they have a plurality of spaced-apart arc-quench plates and two insulating material plates arranged transversely in front of the arc-quench plates next to the contact device in a so-called pre-chamber. Insulating plates, mostly made of ceramic or plastic, are always arranged at a distance from the outer walls of the cabinet. This makes it possible to bypass the plates with arc light gases or to allow pressure equalization.

A disadvantage of these prior art arc-quenching devices is the two additional insulating material boards, which, in addition to the increased costs, also require corresponding installation. In addition, there is a significant risk of breakage if the ceramic plates do not accurately insert and / or slip when closing the housing parts. Easily the malfunction of the switch will then occur due to the fragments of the insulating pads flying around the cabinet.

In order to save the insulation plates, FR 25 75 861 B1 already discloses a solution when the circuit breaker is equipped with integrated arc guides in a pre-chamber. These means consist of opposing rows of ribs on the walls of the arc box housing. Among the rows of ribs which have a tree-like structure or can also be formed as individual straight walls, a central channel remains. Depending on the shape of the fins, the fins are surrounded by grooves or notches that retain the deionized cold gas reserve and, after disconnection, provide backflow of gas in the direction of the contact zone. However, the rib rows standing freely approximately in the middle of the pre-chamber widen the groove between the contacts so that the required switching arc and the resulting gases during the discharge do not occur. In this case, the shape and surface of the grooves are essentially aimed at maintaining a uniform thickness of the ribs, in order to eliminate the bunkers and unevenness of the housing components. Thus, the manufacturing and pressing technical equipment is at the forefront in forming a series of ribs of this switch. On the other hand, optimized gas conduction or rapid discharge of the switching arc from the contact point to the arc quench plates is not achieved with such arc quench chamber.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to simplify the arc chute in the pre-chamber region of a self-acting switch and to provide improved arc guiding and to provide a particularly low flow resistance in the pre-chamber space.

SUMMARY OF THE INVENTION

This is accomplished by a self-contained switch arranged in a housing made of insulating material and comprising a contact device and a switching mechanism, with an arc chute in the housing having a pre-chamber space adjacent to the contact device, and auxiliary means for introducing the switching arc from the contact device The arc extinguishing system according to the invention is characterized in that in the pre-chamber space on at least one side surface of the inner side surfaces of the housing, arranged parallel to the plane opening the movement of the contacts, the webs of insulating material extending from the contact device and further along the arc guiding which besides the gap in the plane of opening of the contacts surround the arc guide to the pre-chamber space and at the same time form sealing walls against the switching mechanism, while in the remaining channel of the pre-chamber space there are posts arranged by sealing walls, protruding from the bottom of the inner side surfaces in the direction of the plane of opening of the contacts.

Preferred embodiments of the invention will now be described.

According to a preferred embodiment of the invention, the housing consists of two halves, the contact device consisting of a fixed contact and a movable contact lever with a single interruption which together form a U-shaped current loop, wherein a quench plate stack oriented perpendicular to the current loop is inserted in the arc chute. the posts are evenly distributed between the contact device and the quench plate stack, and a gap is provided between the end faces of the posts arranged on opposite inner side surfaces of the housing.

According to a further preferred embodiment of the invention, the posts are arranged inside the channel between the sealing walls and against each other such that the intended circles of equal diameter around their heel are adjacent to one another and on the other hand contact the sealing walls on the periphery.

The posts are preferably arranged at equal intervals in a row.

The posts are preferably arranged with their heels in an ideal arc midway between the curved webs.

The columns are preferably arranged with their heels in a zigzag line on the inner side surfaces evenly distributed between the uprights in the channel.

The columns of the first inner side surface are preferably arranged opposite the columns of the second inner side surface of the cabinet with a gap.

The height of the pillars of one inner side surface is preferably equal to the height of the respective webs and their faces are in one plane.

The webs and posts are preferably made of one piece.

Preferably, five to nine columns are arranged on each inner side surface within the pre-chamber space.

Preferably, 5 to 15% of the total channel area between the sealing walls is covered by the base surfaces of the posts.

The posts are preferably round or square and have a side diameter or length of 2 mm.

The posts preferably have a height of 6 mm on both sides of the plane of the contact opening.

The posts are preferably conical with a conicity of 10% and taper in the direction of the contact opening plane.

The gap between the front surfaces of the posts or the upper sides of the webs of both housing halves has a width of 3 mm.

According to a further preferred embodiment of the invention, the fixed contact and the contact device guide as well as the lower arc guide opposite to the contact device are located and fixed on the webs.

The arc chute arrangement according to the invention is advantageous in that the switching arc of light is driven by the magnetic field of the arc of light guiding between the protruding upper sides of the closely adjoining uprights and is laterally narrowly bounded by the end faces of the columns individually distributed in the pre-chamber space. As a result, in addition to better guidance of the arc of light, there is also a high acceleration of the arc of light at low gas pressure. At the same time, the drive effect of the web material and the gas-releasing columns is used to create an additional light arc drive. On the other hand, with side panels closed, this effect is usually already too strong. Furthermore, the pressure of the gas before the light arc can be reduced in the free spaces between the columns, so that the light arc has only a slight flow resistance on its way in the direction of the quench plates and can be quickly and safely removed from the contact point. In the course of the arc of light, the eventual braking pressure difference before and after the arc of light is effectively compensated for by the backflow of gases between the columns. This pressure equalization also causes good deionization of the contact point area behind the arc of light at risk of re-ignition. In addition, the webs in the form of webs increase the escape routes at the contact point. Since the edges of the webs are only slightly loaded by the light arc, the result is high insulation strength even with open contacts. Another particular advantage is that it is possible to achieve a high arc speed and low gas pressure in the pre-chamber space, in addition to the described effects by direct pillar molding as well as sealing walls in the manufacture of duroplastic or thermoplastic casing components at increased cost. By eliminating the conventional insulation boards in the pre-chamber region, the overall cost savings are also considerable.

BRIEF DESCRIPTION OF THE DRAWINGS

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a simplified illustration of a circuit breaker with an upper housing part open in the arc chute area; FIG. 2 shows a section II-II of the arc chute according to FIG. 1, FIG. 3 is a perspective view of the arc chute area of the housing half according to the invention; and FIG. 4 schematically explodes in the area of the inner contours of the two compartment halves separated from each other in the area of the arc chute.

DETAILED DESCRIPTION OF THE INVENTION

The line circuit breaker in the basic embodiment has a housing 1 consisting of two halves 1a, 1b. In the upper part, the housing 1 contains only the indicated switching and breaking mechanism

2. The housing 1, made of duroplastic or thermoplastic material, is in the part located below the switching and stopping mechanism 2, predominantly designed as an arc quenching chamber 3, which is filled predominantly with a row of arc quenching plates 4 arranged parallel to the lower surface lc switch. The depth of the arc chute 3 between its two inner side surfaces 3a, 3b is first determined by the usual wall thickness for manufacturing reasons when starting from the normalized width of the switch limited by the outer walls 1a ', 1b' of the housing 1.

The row 4 of the quench plates 4a, inserted into the quench chamber 3 and abutting the left narrow faces on the wall ld of the housing equipped with the exhaust opening, is limited at its upper and lower longitudinal sides by arc guides 6, 7 facing the contact device 5 The pre-chamber space 3c of the arc chamber 3. For example, when nine arc plates 4a of ferromagnetic material are arranged side by side at a distance, the arc plate 4a fills the completely box-like part of the arc chamber 3 between the two inner side faces 3a, 3b. and is fixed here in a manner not shown in more detail.

The contact device 5 arranged in the upper right corner of the arc chute 3 in the approximately funnel shape of the chamber 3c consists of a fixed contact 5a which is connected to the output terminal 11 via the conductive parts 10a and the trigger coil 10 and This contact lever 5b is connected via the movable guides 12a, 12b with the engagement of the thermal trigger 12 with the input terminal 13 and, in the switch-off operation, it is folded in a counter-clockwise direction. The fixed contact 5a and the contact lever 5b form, in their own contact with their current leads, a current loop, approximately U-shaped, oriented perpendicularly to the quench plates 4a. The individual quench plates 4a have a V-shaped notch 4b on their face facing the pre-chamber 3c, enhancing the arc start, and cover the open contour of the pre-chamber 3c closed by other wall regions 1 against the other regions of the housing 1. They only have recesses for the pivoting movement of the touch lever 5b, so that the pre-chamber space 3c in connection with the arc guide 6, 7 is almost pressure-tight in the direction of the switching and breaking mechanism.

Of particular importance are the narrow webs 3d, 3e, which are two in the pre-chamber space 3c on both side surfaces 3a, 3b, and which prismically project towards the center of the housing 1, which normally have a rectangular cross-section, but may also be trapezoidal or graduated cross section. They are formed directly on the two housing halves 1a, 1b from the base of the outer walls 1a ', 1b' up to about the pivot plane of the movable contact lever 5b and end with their upper side preferably equidistant from the two side surfaces. In the plane of the arc chute 3, i. j. in the plane of the drawing of FIG. 1, the webs 3d, 3e extend approximately equally, but with a different arc shape, from the area of the contact device 5 to the front contour of the row 4 of the quench plates 4a.

The upper web 3 abuts tightly on the fixed contact 5a and follows its guide 5a 'on the side facing the pre-chamber space 3c up to the wall of the arc chute 3 in the region of the upper guide 6 of the arc. Together, the two legs 3d enclose the two housing halves 1a, 1b of the fixed contact 5a on the contact side as well as on both narrow sides so that only a gap corresponding to the width of the contact lever 5b along the guide 5a 'remains in the middle between the legs.

The same is true for the web 3e along the lower arc guide 7. This lower arc guide 7 is also surrounded by the webs 3e on both sides of the longitudinal edges facing the pre-chamber space 3c, so that there is also only a slit of the width of the contact lever 5b which serves to form the heel of the switching light arc 9. 3d, 3e, the arc of light 9 can extend inside the slot into the row 4 of the quench plates 4a. A slight projection 7 'on the lower arc guide 7 near the gap promotes an additional straight course of the light arc 9 foot point. In addition, the light arc drive 9 is also positively influenced by parts of the wider, ferromagnetic lower arc guide 7 covered by lateral webs 3e. since a larger cross-section of the material improves the action on the drive of the arc 9.

Another main feature of the invention are the columns 3f, which are arranged in a larger number in the pre-chamber space 3c and are arranged approximately uniformly in the free cross-section between the webs 3d, 3e. The columns 3f, the cross-section of which is circular or angular, are approximately equidistant from the webs 3d, 3e and each other and extend from the side walls 3a, 3b to almost the swivel plane of the touch lever 5b, so that only a narrow gap remains between their lower faces 3f '. The front surfaces of both groups of posts 3f thus define a light arc 9 drawn at the point of contact in connection with preferably equally high webs 3d, 3e, wherein its foci for the guide 5a 'and the guide 6, 7 are pulled apart and are driven in the contact area in the direction of the quench plates 4a in an accelerated manner, see the arc of light 9 ', 9.

The posts 3f are preferably arranged in a slight lateral zigzag deflection relative to the central ideal line between the two uprights 3d, 3e from the area of contact in the direction of the end walls of the quench plates 4a, but may also be arranged directly in line on this ideal line. Only in the region of the funnel-shaped extension directly in front of the quench plates 4a, two posts are ideally arranged (FIG. 1, FIG. 3). According to an exemplary embodiment, the columns 1f of seven pieces are molded on each half 1a, 1b of the housing 1 immediately in the manufacture of the parts of the housing 1, the columns 3f preferably having a slightly truncated cone shape with an average diameter of approximately 2 mm and a height of approximately 6 mm. Since different circuit breakers 3c are technically advantageous for the circuit breakers because of the shape of the contact device and their position against the guidance of the arc 9 on the one hand and the number of quenching plates 4a and their arrangement in the arc chute 3 on the other also the dependent arrangement of the columns 3f. The number of posts 3f on each part of the housing 1 will essentially depend on the size of the pre-chamber space 3c, the posts 3f preferably being evenly distributed between the contact area and the end faces of the quench plates 4a. Ideally, the pillar groups 3f in both halves of the housing 1 are each arranged in a gap offset, as shown in particular in FIG. Thus, the friction exerted by the posts 3f on the arc 9 is reduced by means of a narrow guide, since only one front surface of the two groups of posts 3f is alternately in operation during the course of the arc of light 9.

Irrespective of the number, size and position of the posts 3f, the posts 3f occupy approximately a base area between 5 to 15% of the area remaining between the webs 3d, 3e in the pre-chamber space 3c, leaving open channels 8 around the posts 3f closed by sealing walls against the other parts of the switch. le and the wall portions of the webs 3d, 3e as well as the sealing walls. Due to the small volume of the columns 3f in relation to the total space of the pre-chamber 3c, an optimally large space for gas expansion thus results, even though the arc of light 9 is guided narrowly and its current density is thus kept as high as possible. The resulting high electrodynamic drive, as well as the virtually negligible friction on the front surfaces of the posts 3f, influence the fast and safe passage of the switching arc 9 from the contact point to the row 4 of the quench plates 4a. The existing expansion space and flow channels around the pillars 3f simultaneously ensure low gas pressure, which in turn reduces the ion concentration and the risk of re-ignition behind the light arc 9. The space behind the fixed contact 5a can serve as a type of silencer and air reserve. if the web 3d containing the guide 5a 'up to the upper guide of the arc 9 ends approximately at the upper side of the contact point. Thereby, a direct flow channel 8 'remains between the end of the web 3d and a portion of the wall 1e, which allows pressure equalization above the contact point up to the actual pre-chamber space 3c.

The described arrangement, which is supplemented by the accompanying drawings and shows both the columns and the overall arrangement of the pre-chamber space of the circuit breaker, can also be used with other automatic switches, while respecting the above criteria. In doing so, the skilled person will have to adapt the columns and webs to the spatial dimensions of the arc chute and the pre-chamber space in individual cases so that the scope of the invention is not impaired.

Claims (16)

An automatic switch arranged in a housing (1) made of insulating material and comprising a contact device (5) and a switching mechanism (2) with an arc chute (3) in the housing (1) having a pre-chamber space (3c) arranged next to it and with auxiliary means for introducing the switching arc from the contacting device (5) into the arc quenching area (4), characterized in that in the pre-chamber space (3c) on at least one side surface of the inner surfaces (3a, 3b) ) housings (1) arranged parallel to the opening movement plane of the contacts are provided with insulating material webs (3d, 3e) extending from the contact device (5) and further along an arc guide (5a ') which apart from the gap in the opening plane of the contacts surround the arc guide (5a) in the pre-chamber space (3c) and at the same time form sealing walls against the switching mechanism (2), while in the remaining channel To the pre-chamber space (3c), columns (3f) extending from the bottom of the inner side surfaces (3a, 3b) in the direction of the plane of opening of the contacts are arranged between the sealing walls. The automatic switch according to claim 1, characterized in that the housing (1) consists of two halves (1a, 1b), the contact device (5) consisting of a fixed contact (5a) and a movable contact lever (5b) with a single break, which together form a U-shaped current loop, wherein a quench plate stack (4) is inserted in the arc chute (3), oriented perpendicularly to the current loop and the posts (3f) are distributed between the contact device (5) and the quench plate stack (4) uniformly and wherein a gap is provided between the end faces (3 f ') of the posts (3f) arranged on opposite inner side faces (3a, 3b) of the housing (1). The automatic switch according to claim 1 or 2, characterized in that the posts (3f) are arranged inside the canary (8) between the sealing walls and the na4 opposite each other so that the intended circles of equal diameter around their heel are adjacent to each other. touching the sealing walls on the perimeter. The automatic switch according to claims 1 to 3, characterized in that the posts (3f) are arranged at equal intervals in a row. The automatic switch according to claims 1 to 4, characterized in that the posts (3f) are arranged by their heels in an ideal arc in the middle between the curved webs (3d, 3e). The automatic switch according to one of claims 1 to 4, characterized in that the columns (3f) are arranged with their heels in a zigzag line on the inner side surfaces (3a, 3b), evenly distributed between the uprights (3d, 3e) in the channel (8). ). The automatic switch according to one of claims 1 to 6, characterized in that the posts (3f) of the first inner side surface (3a) are arranged offset from the posts (3f) of the second inner side surface (3b) of the housing (1). The automatic switch according to claims 1 to 7, characterized in that the height of the posts (3f) of one inner side surface (3a, 3b) is equal to the height of the respective webs (3d, 3e) and their faces (3f ') lie in one plane. The automatic switch according to claims 1 to 8, characterized in that the webs (3d, 3e) and the posts (3f) are made in one piece. The automatic switch according to claims 1 to 9, characterized in that five to nine columns (3f) are arranged on each inner side surface (3a, 3b) inside the pre-chamber space (3c). The automatic switch according to claim 1 to 10, characterized in that 5 to 15% of the total area of the channel (8) between the sealing walls is covered by the base surfaces of the posts (3f). The automatic switch according to claims 1 to 11, characterized in that the posts (31) are of round or square shape and have a side diameter or length of 2 mm. The automatic switch according to one of claims 1 to 12, characterized in that the posts (3f) each have a height of 6 mm on both sides of the plane of the contact opening. The automatic switch according to claims 1 to 13, characterized in that the posts (3f) are conical with a conicity of 10% and taper in the direction of the contact opening plane. The automatic switch according to claims 1 to 14, characterized in that the gap between the end faces (3f j of the posts (3f) or the upper sides of the webs (3d, 3e), the two halves (1a, 1b) of the housing (1) has a width 3 mm. The automatic switch according to claims 1 to 15, characterized in that the fixed contact (5a) and the guide (5a ') of the contact device (5) as well as the lower arc guide (7) opposite to the contact device (5) are located. and mounted on the webs (3d, 3e).