DE102021126432A1 - BI-DIRECTIONAL ARC FLASH EXTINGUISHING DEVICE - Google Patents

Abstract

The present invention relates to a bidirectional switching device with at least one contact point and at least one arc blowing device assigned to the contact point, the contact point having a fixed contact and a movable contact, and the movable contact moving from an open position along a closing direction to a closed position and thereby can be brought into contact with the fixed contact in order to electrically connect the movable contact with the fixed contact, a first transverse direction being defined orthogonally to the closing direction, and a second transverse direction being defined both orthogonally to the closing direction and orthogonally to the first transverse direction, such that the closing direction, the first transverse direction and the second transverse direction together span an orthogonal coordinate system, with the arc blowing device having a blowing magnet and a ferromagnetic profile which interacts with the blowing magnet and is magnetically connected to the blowing magnet to generate a magnetic blowout field, the magnetic blowout field being such that a When the contact point is opened, the switching arc that occurs is blown away from the contact point, the ferromagnetic profile having a profile cross-section open on one side and being arranged in such a way that the profile cross-section, viewed in the first transverse direction, is open towards the contact point and surrounds the contact point on both sides, viewed in the second transverse direction, wherein magnetic field lines of the magnetic blowout field are fanned out in such a way that the switching arc is driven depending on the current direction viewed in the second transverse direction either to a first side or to an opposite second side and in both cases in the first transverse direction away from the contact point towards the ferromagnetic profile is blown, and wherein the blow magnet is arranged within the ferromagnetic profile. According to the invention, the blowout magnet is arranged centrally in relation to the profile cross section of the ferromagnetic profile, with the direction of magnetization of the blowout magnet coinciding with the first transverse direction.

Description

The present invention relates to a bidirectional switching device according to the preamble of independent claim 1.

A bidirectional switching device according to the preamble of independent claim 1 has at least one contact point and at least one arc blowing device assigned to the contact point, the contact point having a fixed contact and a movable contact, and the movable contact moving from an open position along a closing direction into a closed position and can be brought into contact with the fixed contact in order to electrically connect the movable contact to the fixed contact, a first transverse direction being defined orthogonally to the closing direction, and a second transverse direction being defined both orthogonally to the closing direction and orthogonally to the first transverse direction, so that the closing direction, the first transverse direction and the second transverse direction together span an orthogonal coordinate system, with the arc blowing device having a blowing magnet and a ferromagnetic profile which interacts with the blowing magnet and is magnetically connected to the blowing magnet to generate a magnetic blowout field, the magnetic blowout field being configured in this way that a switching arc occurring when the contact point is opened is blown away from the contact point, with the ferromagnetic profile having a profile cross-section open on one side and being arranged in such a way that the profile cross-section, viewed in the first transverse direction, is open towards the contact point and the contact point in the second transverse direction viewed on both sides, with magnetic field lines of the magnetic blowout field being fanned out in such a way that the switching arc, viewed in the second transverse direction, is driven either to a first side or to an opposite second side, depending on the direction of the current, and in both cases in the first transverse direction away from the contact point blown towards the ferromagnetic profile, and wherein the blown magnet is located within the ferromagnetic profile.

A bi-directional switching device according to the preamble of independent claim 1 is off U.S. 2012/145675 A1 known. The profile cross-section, which is open on one side, forms two channels open towards the contact point. These are formed by two outer walls, which surround the contact point viewed in the second transverse direction, and by a central partition wall aligned in the first transverse direction, which is part of both channels. Blower magnets are arranged on each of the two outer walls, the directions of magnetization of which lying in the second transverse direction are aligned in opposite directions. This creates a blowout field that blows the switching arc away from the contact point and into one of the channels, depending on the direction of the current. This results in an elongation and extinction of the switching arc that is independent of the current direction.

However, such a design requires a lot of space. In the automotive sector in particular, there is a need for bi-directional switching devices that enable a compact design with effective arc quenching that is independent of the current direction and a high switching capacity.

The object of the present invention is therefore to further develop and improve the bidirectional switching device according to the preamble of independent claim 1 in such a way that an improved compact design is made possible with a high switching capacity.

The object is achieved by the features of independent claim 1. Accordingly, in the case of a bidirectional switching device according to the preamble of independent claim 1, the object is achieved according to the invention if the blowout magnet is arranged centrally in relation to the profile cross section of the ferromagnetic profile, with the magnetization direction of the blow magnet coincides with the first transverse direction.

A very compact design is achieved by the solution according to the invention. At the same time, a very effective arc quenching is made possible by the fact that a strong blowout field can be built up, with the arc first being lengthened from its switching arc extension direction at the time of creation, which corresponds to the closing direction, depending on the current direction in the second transverse direction and then being blown in the direction of the neutral fiber of the blowout magnet . The strength of the magnetic field increases, which leads to a further elongation of the arc. As a result of this effective arc extinguishing, the bidirectional switching device according to the invention has a high switching capacity.

A longitudinal axis of the ferromagnetic profile is preferably aligned essentially parallel to the closing direction. This means that a longitudinal axis of the ferromagnetic profile has a maximum angle of +/- 20° to the closing direction. More preferably, the longitudinal axis of the ferromagnetic profile is aligned parallel to the closing direction. This enables a particularly compact arrangement, since the contact point and the ferromagnetic profile can be arranged in a compact manner in relation to one another.

More preferably, the ferromagnetic profile, the fixed contact and the movable contact are designed and arranged mirror-symmetrical to a common plane of symmetry. The plane of symmetry is preferably arranged orthogonally to the first transverse direction. This results in an arc quenching and thus switching capacity that is independent of the current direction.

The switching device can have two contact points, each of which is assigned its own arc blowing device according to the invention. The movable contacts of the two contact points can be arranged on a common movable contact bridge. The directions of magnetization of the blow-out magnets of the two arc blow-out devices are preferably aligned parallel and opposite. More preferably, the longitudinal axis of the contact bridge is also arranged parallel to the two directions of magnetization of the blowout magnets.

Advantageous embodiments of the present invention are the subject matter of the dependent claims.

In a preferred embodiment of the present invention, it is provided that the fixed contact, viewed in the second transverse direction, has a greater extent than the movable contact, so that a first base point of the switching arc existing on the fixed contact at a point caused by the blowout field and leading away from the contact point Movement of the switching arc in the second transverse direction is driven further away from the point at which the switching arc originates than a second base point of the switching arc existing on the movable contact, as a result of which the switching arc is subsequently also deflected in or against the closing direction and is thereby additionally lengthened . In this case, the greater extent of the fixed contact can also mean that two arc guide plates protruding in opposite directions in the second transverse direction are connected to the actual fixed contact. By using such a fixed contact, the switching capacity of the switching device can be additionally increased, since the movement of the first base point of the switching arc on the fixed contact enables an additional elongation of the switching arc. More preferably, the fixed contact extends in the second transverse direction and the first transverse direction in such a way that the fixed contact extends under the ferromagnetic profile in the closing direction. In this way, the first base point of the switching arc can be blown close to the ferromagnetic profile, thereby lengthening it more and ultimately quenching it better.

According to a further particularly preferred embodiment of the present invention, it is provided that the cross section of the ferromagnetic profile is U-shaped, with the blowout magnet being in contact with a bottom of the profile, and with the profile having two lateral legs protruding from the bottom, the magnetic pole plates of the arc blowing device. This embodiment contributes to a very compact design of the switching device. At the same time, this arrangement can create a very strong blowout field that effectively lengthens and extinguishes the switching arc.

According to a further preferred embodiment of the present invention, it is provided that both the ferromagnetic profile and the blowout magnet are protected from the switching arc by a lining, with the lining also being intended to ensure that the switching arc ultimately strikes the lining due to the effect of the magnetic blowout field and extinguished by the liner. This also enables a very compact switching device. Since the ferromagnetic profile, protected by the lining, draws the switching arc to itself and extinguishes it there, no further arc extinguishing elements are required, which means that the entire switching device can be constructed in a particularly compact manner. The fixed contact preferably extends up to or under the lining. In this way, the first base point of the switching arc on the fixed contact can be blown up to the lining, which enables the switching arc to be stretched particularly far.

The lining is preferably made of plastic or ceramic.

According to a further particularly preferred embodiment, the lining in the area of the blow-out magnet has a stepped elevation extending towards the contact point. If the switching arc is not extinguished beforehand, the arc is blown to the neutral phase of the blowout magnet and thus to the stepped elevation by the blowout field. The switching arc is caught there, which enables a defined end position of the switching arc. At the same time, the magnetic field strength is highest there, which leads to increased extinguishing capacity in this position.

According to a further particularly preferred embodiment of the present invention, it is provided that only a single blowout magnet is provided per arc blowout device. This simplifies the structure of the construction. At the same time, this can be particularly compact.

According to a further particularly preferred embodiment of the present invention, it is provided that the blowout magnet is designed as a bar magnet, with a longitudinal extent of the blowout magnet coinciding with a longitudinal extent of the ferromagnetic profile. A thickness of the blow magnet measured in the first transverse direction is preferably smaller than a width of the blow magnet measured in the second transverse direction. This also simplifies the construction of the structure, which can at the same time be constructed in a particularly compact manner.

According to a further preferred embodiment of the present invention, the bi-directional switching device is designed to be sealed. This means that when the contact point opens, a local pressure increase is generated, which has a positive effect on the switching arc being extinguished and thus on the switching capacity. However, the bidirectional switching device is preferably not designed to be gas-tight. This can prevent a risk of explosion.

An exemplary embodiment of the present invention is explained in more detail below with reference to drawings.

• 1: ein erfindungsgemäßes bi-direktionale Schaltgerät gemäß einem Ausführungsbeispiel in einer perspektivischen Draufsicht,
• 2 a, b: eine Oberansicht sowie eine Seitenansicht des erfindungsgemäßen Schaltgeräts,
• 3: einen Querschnitt durch das erfindungsgemäße Schaltgerät entlang der in 2 a eingezeichneten Schnittlinie V,
• 4: durch das erfindungsgemäße Schaltgerät entlang der in 2 b eingezeichneten Schnittlinie VI.

Show it:

• 1 : an inventive bidirectional switching device according to an embodiment in a perspective top view,
• 2a, b : a top view and a side view of the switching device according to the invention,
• 3 : a cross section through the switching device according to the invention along the in 2 a marked cutting line V,
• 4 : by the switching device according to the invention along the in 2 B marked cutting line VI.

For the following explanations, the same parts are denoted by the same reference symbols. If a figure contains reference symbols that are not discussed in more detail in the associated description of the figures, reference is made to the preceding or following descriptions of the figures.

The 1 until 4 show a first exemplary embodiment of a bidirectional switching device 1 according to the invention. The switching device 1 has a first fixed contact 2, a second fixed contact 2' and a contact bridge 3 with a first and a second movable contact 4, 4', which can be moved from an open position along a closing direction z can be converted into a closed position in order to bring the two fixed contacts 2, 2' into contact with the movable contacts 4, 4' and to connect them electrically to one another. The first fixed contact 2 forms a contact point with the first movable contact 4 and the second fixed contact 2 'forms a second contact point with the second movable contact 4'.

The longitudinal axis of the contact bridge 3 is aligned parallel to a first transverse direction x, a second transverse direction y being defined, which is orthogonal to the closing direction z and the first transverse direction x.

The fixed contacts 2, 2' have a greater extent than the movable contacts 3, 3', particularly when viewed in the second transverse direction y.

Arranged at the first and second contact points are arc blowing devices with a blowing magnet 5, 5' and a U-shaped ferromagnetic profile 6, 6' as a pole plate. Viewed in the first transverse direction x, the cross section of the U-shaped profile 6 , 6 ′ is open towards the respective contact point and has a bottom 7 and a first and second leg 8 . The first and second legs 8 are aligned orthogonally to the second transverse direction y and surround the respective contact point in this direction. It should be noted that the U-shaped profile 6, 6′ is arranged above the respective fixed contact 2, 2′ in the closing direction z and the respective fixed contact 2, 2′ extends below the bottom 7 of the respective profile in the first transverse direction x 6, 6' and in the second transverse direction y to below the two legs 8 of the respective profile 6, 6'. A blowout magnet 5, 5' is arranged on the floor 7 within the respective U-shaped profile 6, 6`, the magnetization direction of which runs parallel to the first transverse direction x, the magnetization direction of the blowout magnet 5 of one arc blower device being aligned with the magnetization direction of the blowout magnet 5` of the other Arc blower runs in opposite directions. This creates an as in 3 The blowout field shown for an arc blower device with magnetic field lines 10.

The bi-directional switching device 1 also has a lining 11 which is arranged between the respective contact point and the respective arc blower device with regard to the first and second transverse direction x, y, the lining 11 around the respective blower magnet 5 extending in a stepped manner towards the contact point Elevation 12 has. The lining 11 is arranged on the respective fixed contact 6 in the closing direction z and forms an arcing chamber 13 assigned to the respective contact point. The liner 11 together with a housing 14 and The fixed contacts 2, 2' form a largely sealed switching device 1, although this is not designed to be gas-tight.

The arc quenching in the exemplary embodiment shown of a switching device 1 according to the invention takes place as follows. Since a switching arc always runs perpendicularly to the magnetic field lines of a blowout field, a switching arc 9, which initially forms in the closing direction z between the respective fixed contact 2, 2' and movable contact 4, 4', is, depending on the direction of the current, caused by the current generated in the respective arc blowing device Blasfeld first deflected in the second transverse direction y. It is then pulled towards the bottom 7 of the respective U-shaped ferromagnetic profile on the liner 11 and then pulled to the neutral axis of the respective blow-out magnet 5 in the region of the stepped elevation 12 of the liner 11 . Due to the extension of the respective fixed contact 2, 2', a first base point of the switching arc 9 on the fixed contact 2, 2' migrates first in the direction of a leg 8, then to the bottom 7 and finally to the neutral fiber of the blowout magnet 5. There it is then caught at the stepped elevation 12 of the liner 11 . Since the second base point of the switching arc 9 on the movable contact 4, 4' cannot leave this, the switching arc stretches at the same time in the closing direction z and is also lengthened as a result. Since the magnetic field strength to the neutral fiber of the blowout magnet 5 increases, the quenching capacity increases at the same time as the switching arc 9 moves, since the switching arc is stretched further by the increasing magnetic field. As soon as the switching arc 9 reaches a critical length, it goes out.

Since the switching device 1 is designed to be largely sealed, the formation of a switching arc 9 causes an excess pressure, which at the same time promotes the rapid extinguishing of the switching arc 9 .

At this point it should be pointed out that some of the illustrations are of a schematic nature. Various elements such as the movement mechanism of the contact bridge 3 are not shown.

reference list

1

bi-directional switching device

2, 2'

fixed contact

3

contact bridge

4, 4'

moving contact

5, 5'

blow magnet

6, 6'

ferromagnetic profile

7

Floor

8th

leg

9

switching arc

10

magnetic field line

11

lining

12

stepped elevation

13

arcing chamber

14

Housing

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• US2012145675A1 [0003]

Claims (10)

Bidirectional switching device with at least one contact point and at least one arc blowing device assigned to the contact point, the contact point having a fixed contact and a movable contact, and wherein the movable contact moves from an open position along a closing direction into a closed position and is in contact with the fixed contact can be brought in order to electrically connect the movable contact to the fixed contact, a first transverse direction being defined orthogonally to the closing direction, and a second transverse direction being defined both orthogonally to the closing direction and orthogonally to the first transverse direction, such that the closing direction, the first transverse direction and the second transverse direction together span an orthogonal coordinate system, with the arc blower device having a blower magnet and a ferromagnetic profile which interacts with the blower magnet and is magnetically connected to the blower magnet for generating a magnetic blowout field, the magnetic blowout field being such that a switching arc occurs when the contact point is opened is blown away from the contact point, with the ferromagnetic profile having a profile cross-section open on one side and being arranged in such a way that the profile cross-section, viewed in the first transverse direction, is open towards the contact point and, viewed in the second transverse direction, surrounds the contact point on both sides, with magnetic field lines of the magnetic blast field are fanned out in such a way that the switching arc, viewed in the second transverse direction, is driven either to a first side or to an opposite second side, depending on the direction of the current, and in both cases is blown in the first transverse direction away from the contact point towards the ferromagnetic profile, and wherein the blowout magnet is arranged within the ferromagnetic profile, characterized in that the blowout magnet is arranged centrally in relation to the profile cross section of the ferromagnetic profile, the magnetization direction of the blowout magnet coinciding with the first transverse direction. Bi-directional switching device according to claim 1 , characterized in that the fixed contact, viewed in the second transverse direction, has a greater extent than the movable contact, so that a first base point of the switching arc on the fixed contact, when the switching arc moves away from the contact point and is caused by the blowout field, in the second Transverse direction is driven further away from the point of origin of the switching arc than a second base point of the switching arc existing on the movable contact, whereby the switching arc is subsequently also deflected in or against the closing direction and is thereby additionally lengthened. Bi-directional switching device according to claim 1 or 2 , characterized in that the cross-section of the ferromagnetic profile is U-shaped, the blowout magnet being in contact with a bottom of the profile, and the profile having two lateral legs projecting from the bottom, which form magnetic pole plates of the arc blower. Bi-directional switching device according to one of Claims 1 until 3 , characterized in that both the ferromagnetic profile and the blowout magnet are protected from the switching arc by a lining, the lining also being intended to ensure that the switching arc is ultimately extinguished on the lining and through the lining due to the effect of the magnetic blowout field becomes. Bi-directional switching device according to claim 4 , characterized in that the lining consists of plastic. Bi-directional switching device according to claim 4 , characterized in that the lining is made of ceramic. Bi-directional switching device according to one of Claims 4 until 6 , characterized in that the lining in the region of the blow-out magnet has a stepped elevation extending towards the contact point. Bi-directional switching device according to one of Claims 1 until 7 , characterized in that only a single blowout magnet is provided per arc blowout device. Bi-directional switching device according to one of Claims 1 until 8th , characterized in that the blowout magnet is designed as a bar magnet, with a longitudinal extent of the blowout magnet coinciding with a longitudinal extent of the ferromagnetic profile. Bi-directional switching device according to claim 9 , characterized in that a thickness of the blow magnet measured in the first transverse direction is smaller than a width of the blow magnet measured in the second transverse direction.

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