High voltage arc quenching system and electrical switching device including the same

Abstract

To provide an arc quenching system for suppressing an arc between at least one contact pair of an electrical switching device.SOLUTION: An arc-quenching system provides enhanced arc suppression in direct correlation with a preferential electric polarity of operation of a switching device by magnetically blowing an arc discharge generated at a contact pair towards a dedicated arc chute. The arc chute is relatively positioned in the direction of the Lorenz force produced for one given direction of the arc discharge. As a result, in addition to the advantage provided by the magnetically assisted arc-quenching, the amount of arc chutes provided in the switching device may be reduced to a minimum since only one arc chute per contact pair is required for receiving and extinguishing the arc discharge produced at each contact pair.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to the field of arc suppression, and more particularly to an arc quenching system for suppressing arcs between contacts of switching devices designed to operate under high loads, such as contactors and high voltage relays, and a switching device comprising the arc quenching system. [Background technology]

[0002] Electrical switching devices such as contactors and high voltage relays are widely used in a wide range of applications where high power must be safely delivered to load circuits, such as in vehicles, equipment for charging power batteries, industrial equipment, and the like.

[0003] A contactor or relay in a typical configuration typically includes a moving contact and a respective stationary contact that remain in direct contact with each other during normal power delivery operation by closing the power delivery path to the load circuit. When the moving contact moves away from the stationary contact, the contactor or relay opens, thereby interrupting the power delivery path. However, due to the high currents flowing or to flow through the moving and stationary contacts, high current discharges (or arc currents) may still occur across the separation gap between the moving and stationary contacts when the contactor or high voltage relay opens and / or closes. For this reason, it is common for such switching devices to include safety mechanisms to suppress (or eliminate) the arc current and protect the switching device and the load circuit from the harmful effects of arcing. For example, arc chutes for interrupting the arc are widely used in combination with guide runners that guide and direct the arc to the arc chute.

[0004] Key parameters of efficiency and reliability of a safe system for arc suppression are the contact distance (i.e., the distance between the moving contact in the open state and the respective stationary contact) and the expected voltage drop. For example, a high-voltage contactor operating at a voltage load of 800V may require a larger contact distance to interrupt an arc than a relay operating at a lower voltage. However, the increased contact distance not only means that the overall size of the relay is larger, but also that the actuator responsible for the movement of the moving contact must be more robust to cover the larger contact distance to return the moving contact from the open state back to the closed state. For example, in the case of an electromagnetic relay, it may not be feasible to implement a coil-induced magnetic actuator robust enough to close a large contact distance relay.

[0005] Therefore, considering the constant need for safe equipment that can operate under increasing high voltage loads and at the same time is compact in size, some approaches have been tried to enhance the arc suppression by other factors that rely only on increasing the physical separation between the moving contact and the stationary contact. For example, a bridge approach is used that splits the contact voltage into two. However, the arc discharge per contact is still strong enough or difficult to interrupt with the contact distances used in common contacts and relays. Moreover, this solution still has the problem that the relay cannot interrupt a wide range of high voltage arcs with a small contact distance.

[0006] Another approach relies on using magnetic arc suppression to compensate for the shortened contact distance and help achieve the same or enhanced arc suppression while using a smaller contact distance. This approach is based on extending the path that the arc must travel between the contacts by adding magnets that can create a magnetic field in the area between the moving and stationary contacts that is strong enough to displace the arc current along the extended arc length. Enhanced arc suppression can thereby be achieved when this extended path is greater than the energy available to overcome it. However, this approach has some limitations. For example, the size of the magnets required to achieve the required enhanced effect on arc suppression can adversely affect the compactness of the contactor or high voltage relay. Inexpensively available magnets may not have the strength required to achieve the required arc suppression.

[0007] Therefore, in view of the ever-developing electrical equipment that operates at ever-higher voltages, a need remains for a solution that can provide enhanced high voltage arc suppression in electrical switching devices without compromising the compactness and overall cost of the switching device. Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the shortcomings and drawbacks of the prior art, and has an object to provide an arc quenching system and an electrical switching device that can provide enhanced high voltage arc suppression without compromising compactness in size and overall cost. It is a further object of the present invention to provide an arc quenching system and a switching device including the arc quenching system having a structure that can extend the arc discharge path and divert the arc discharge path from the gap area between the contacts of the switching device to provide effective arc suppression for a given high voltage load without having to excessively change the width of the gap area. [Means for solving the problem]

[0009] These objects are solved by the subject matter of the attached independent claims. Advantageous embodiments of the invention are the subject matter of the attached dependent claims.

[0010] The underlying concept of the present invention is based on providing a high voltage arc quenching solution that can efficiently suppress arcs occurring between moving and stationary contacts of an electrical switching device by adding a magnetic mechanism that can interrupt the arc by magnetically blowing (i.e., deflecting) the arc away from the discharge zone towards an arc chute located near the contact pair.

[0011] According to the present invention, there is provided an arc quenching system for suppressing an arc across at least one contact pair of an electrical switching device, each contact pair having a stationary contact and a movable contact, the movable contact being movable relative to the stationary contact between a closed state in which the movable contact is in contact with the stationary contact and an open state in which the movable contact is spaced apart from the stationary contact by a gap in a direction of relative movement between the movable contact and the stationary contact, the arc quenching system comprising at least one arc quenching unit, one arc quenching unit provided for each of the at least one contact pair, for quenching an arc discharge occurring upon switching of the corresponding contact pair from a closed state to an open state, and at least one arc-blowing magnetic unit configured to generate a magnetic field having magnetic field lines along a respective predetermined magnetic field direction and across a gap region of each contact pair. and at least one arc blow magnetic unit configured to generate magnetic field lines in a predetermined direction based on a preferred electrical polarity of the stationary contacts of each contact pair and a position of an associated arc quenching unit to magnetically blow an arc discharge generated in a gap region of each contact pair towards the arc quenching unit associated with the contact pair.

[0012] In a further development, the at least one contact pair comprises a first contact pair and a second contact pair arranged adjacent to each other along a longitudinal direction transverse to the direction of relative movement, the at least one arc blow magnetic unit comprises one arc blow magnetic unit configured to generate said magnetic field having magnetic field lines crossing the gap area of ​​the first and second contact pairs along said predetermined magnetic field direction, the arc blow magnetic unit being configured to be arranged relative to the first and second contact pairs such that the predetermined magnetic field direction is parallel to the longitudinal direction, and / or the at least one arc quenching unit comprises a first arc quenching unit configured to be located opposite the first contact pair and a second arc quenching unit configured to be located opposite the second contact pair, the first arc quenching being arranged on one side of a plane of symmetry parallel to the longitudinal direction crossing the first and second contact pairs along the direction of relative movement.

[0013] In a further development, the at least one contact pair comprises a first contact pair and a second contact pair arranged adjacent to each other along a longitudinal direction transverse to the direction of relative movement, the at least one arc blow magnetic unit comprises a first arc blow magnetic unit configured to generate a first magnetic field having magnetic field lines along a first predetermined magnetic field direction in the area of ​​a gap of the first contact pair and a second arc blow magnetic unit configured to generate a second magnetic field having magnetic field lines along a second predetermined magnetic field direction in the area of ​​a gap of the second contact pair, the second arc blow magnetic unit being spaced apart from the first arc blow magnetic unit, and / or the at least one arc quenching unit comprises a first arc quenching unit configured to be located opposite the first contact pair and a second arc quenching unit configured to be located opposite the second contact pair, the first arc quenching being located on one side of a plane of symmetry between the first contact pair and the second contact pair, transverse to said longitudinal direction along the direction of relative movement.

[0014] In a further development, the stationary contacts of the first and second contact pairs have opposite polarities and the second arc quenching unit associated with the second contact pair is located on a side of the symmetry plane opposite to the side on which the first arc quenching unit associated with the first contact pair is located.

[0015] In a further development, each of the at least one arc quenching unit comprises a number of split blades arranged parallel to one another and configured to split the voltage of the arc discharge across the arc quenching unit.

[0016] In a further development, the multiple split blades are multiple L-shaped plates arranged with the short leg of the L oriented to protrude toward the gap area of ​​the associated contact pair, and the multiple split blades are further arranged transversely to the direction of relative movement.

[0017] In a further development, each of the at least one arc quenching unit includes an electrical contact element configured to make a direct electrical connection between the split blade and a terminal of a switching device to which the stationary contact of the respective contact pair is attached, and / or each arc quenching unit is located opposite a gap region of the respective contact pair.

[0018] In a further development, each of the at least one arc blow magnetic unit comprises a first permanent magnet and a second permanent magnet, the first permanent magnet and the second permanent magnet being arranged with their front faces facing each other such that magnetic flux lines in the gap area of ​​the associated contact pair flow from the front face of the first permanent magnet towards the front face of the second permanent magnet along the predetermined magnetic field direction.

[0019] In a further development, the arc blow magnetic unit further includes a flux frame in which the first permanent magnet and the second permanent magnet are mounted, the flux frame being configured to provide a magnetic flux path for magnetic field lines flowing from a rear surface of the second permanent magnet to a rear surface of the first permanent magnet.

[0020] In a further development, the flux frame is a plate having a U-shape defined by a central plate and two extension arms extending respectively from the left and right sides of the central plate, the central plate being configured to mount the flux frame to a chassis of the switching device, and the first permanent magnet and the second permanent magnet are each positioned on the extension arms of the flux frame at a distance from the central plate that is adapted to position the first permanent magnet and the second permanent magnet in alignment with the gap regions of the respective contact pairs when the flux frame is mounted to the chassis of the switching device.

[0021] In a further development, the magnetic polarization of the first and second permanent magnets is selected according to an orientation established for the preferred electrical polarity of each stationary contact such that the resulting magnetic field lines are directed from the first permanent magnet to the second permanent magnet in the gap region of each contact pair.

[0022] According to the present invention there is further provided an electrical switching device comprising a first contact pair and a second contact pair arranged adjacent to each other along a longitudinal direction of the electrical switching device, each of the first contact pair and the second contact pair including a stationary contact and a movable contact, the movable contact being movable relative to the stationary contact between a closed state in which the movable contact is in contact with the stationary contact and an open state in which the movable contact is spaced from the stationary contact by a gap in a direction of relative movement between the movable contact and the stationary contact, the electrical switching device comprising an arc quenching system as defined in any one of claims 1 to 11, the arc quenching system being arranged in alignment with the first contact pair and the second contact pair, at least one arc blow magnetic unit generating the magnetic field having magnetic field lines along a respective predetermined magnetic field direction and across the gap region of each contact pair, each arc quenching unit being located opposite a respective contact pair.

[0023] In a further development, the electrical switching device further comprises a first terminal and a second terminal connected to the stationary contacts of the first and second contact pairs, respectively, the first terminal and the second terminal being configured to electrically connect the switching device to an external potential or to a load circuit according to a preferred polarity of operation of the switching device.

[0024] In a further development, the switching device is a contactor or a high-voltage relay.

[0025] In a further development, the electrical switching device and the arc quenching system does not have a guide runner for guiding the arc discharge between the first and second contact pairs directly towards an associated arc quenching unit.

[0026] Thus, the present invention uses a magnetic blow effect based on the Lorentz force principle instead of sending the arc directly to the arc chute, thereby eliminating the need for a guide runner to guide the arc towards the arc chute, as is commonly used in conventional switching devices. Furthermore, for the same contact distance, the arc suppression is enhanced, since the magnetic blow effect effectively extends the arc path between the moving and stationary contacts of a contact pair. In addition to the magnetic enhancement of arc suppression, additional advantageous effects of the claimed invention are that it requires less space to implement, the contact life is increased, the contact voltage is increased, and even the contact distance can be reduced.

[0027] The invention can be used in any application where increased arc voltage resistance is required. In particular, the claimed invention can be advantageously used in low resistance contactors and relays, protection devices against battery discharge, power equipment in industrial equipment and vehicles such as electric cars.

[0028] The accompanying drawings are incorporated in and form a part of this specification to illustrate some embodiments of the present invention. These drawings, together with the description, serve to explain the principles of the present invention. The drawings are only intended to illustrate preferred and alternative examples in which the present invention can be made and used, and should not be construed as limiting the present invention to only the embodiments shown and described. Furthermore, some aspects of the embodiments can be formed individually or in different combinations to form a solution according to the present invention. Thus, the embodiments described below can be considered alone or in any combination.

[0029] Further features and advantages will become apparent from the following more particular description of various embodiments of the invention, as illustrated in the accompanying drawings, in which like reference numerals refer to like elements, and in which: [Brief description of the drawings]

[0030] [Figure 1]FIG. 2 is a perspective view of an arc quenching system and a switching device according to an embodiment of the present invention. [Diagram 2] 2 is a side cross-sectional view showing a section through the switching device of FIG. 1 taken along intersection line AA′ shown in FIG. 1 (looking in the positive Y direction). [Diagram 3] FIG. 2 is a perspective view of an arc-blow magnetic unit of an arc extinguishing system according to an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic diagram showing the orientation of the magnetic field lines of the magnetic field (Bmag) generated in the intermediate region where the movable and stationary contacts are located by the arc blow magnetic unit of FIG. 3, the direction of the magnetic field (BBridge) generated by the current flowing along the contact bridge between the two contact pairs of the switching device, and the direction of the magnetic field (Barc) generated by the arc columns generated at each contact pair, where the resultant Lorenz force (F) acting on each arc column has opposite directions due to the opposite directions of the current associated with the arc discharge generated at each contact pair. [Diagram 5] FIG. 13 is a perspective view of an arc quenching system and a switching device according to a further embodiment of the present invention. [Figure 6] 6 is a schematic cross-sectional view of a section through the switching device of FIG. 5 along line BB' shown in FIG. 5 (looking in the positive Y direction). [Figure 7] 2 is a schematic diagram illustrating a pair of stationary and movable contacts of a contact pair and an arc chute directly connected to a terminal of the stationary contact by a conductive element according to an embodiment of the present invention. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] The present invention will now be described more fully with reference to the drawings, in which exemplary embodiments of the invention are shown. However, the present invention may be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art.

[0032] FIG. 1 is a schematic perspective view of a switching device 100 and an arc quenching system for protecting a contact assembly of the switching device 100 in accordance with an embodiment of the present invention. The switching device 100 may be a contactor, a high voltage relay, or the like. Components of the switching device, such as an electromagnetic drive mechanism for operating the contact assembly of the switching device, a housing, and the like, are omitted in FIG. 1 to facilitate illustrating the mechanism of the arc quenching system in accordance with the present invention and explaining its operating principles. For ease of reference, the term "contactor" is used in the following description when referring to a switching device in accordance with the principles of the present invention. However, it should be understood that the present disclosure is also applicable to other types of switching devices, such as high voltage relays.

[0033] As shown in Fig. 1, the contactor 100 includes an assembly of contacts operable to switch between a closed state and an open state to connect and disconnect the contactor 100 to lines of an external power source and / or load circuit (not shown). In particular, the contact assembly includes a plurality of stationary contacts, e.g., two stationary contacts 102, 104 in the illustrated configuration, arranged adjacent to one another along a longitudinal direction L of the contactor 100 (i.e., the Y direction in Fig. 1). Each of the stationary contacts 102, 104 is disposed at a respective terminal 106, 108 through which the contactor 100 is connected to an external potential, such as the terminals of a power source equipment and / or load (not shown). The contacts 102, 104 are stationary in the sense that they do not move relative to other fixed parts of the contactor 100, such as the contactor chassis 130.

[0034] The contact assembly further includes a plurality of movable contacts 112, 114 (preferably the same number as the stationary contacts 102, 112) disposed adjacent to one another along a longitudinal direction L. The movable contacts 112, 114 are movable with respect to the chassis 130 and the stationary contacts 102, 104 between a closed state and an open state of the contactor 100 along a direction of relative movement T perpendicular to the longitudinal direction L in which the stationary contacts 102, 104 and the movable contacts 112, 114 are disposed. Each of the movable contacts 112, 114 is disposed opposite and aligned with a respective one of the stationary contacts 102, 104 to form a respective contact pair. Thus, each contact pair, such as the pair of movable contact 112 and stationary contact 102, establishes an electrical path when the movable contact 102 and stationary contact 114 are in direct contact with one another (closed state), and the electrical path is interrupted upon movement of the movable contact 112 away from the stationary contact 104 in the direction of relative movement T (open state). In the open state, the movable contacts 112, 114 are separated from the stationary contacts 102, 104 in the direction of relative movement T by a gap of a given contact distance.

[0035] The movable contacts 112, 114 are preferably attached to a contact bridge 120 extending parallel to a longitudinal direction L, which can move along a direction of relative movement T towards and away from the stationary contacts 102, 104 under the actuation of an armature of a drive mechanism, e.g. an electromagnetic driver (not shown), during a switching operation to bring the movable contacts 112, 114 into direct contact with the respective stationary contacts 102, 104 to close the contact pair, or to separate the movable and stationary contacts 102, 104 to open the contact pair. The contact bridge 120 is preferably formed from a conductive material to electrically connect the movable contacts 112, 114 to each other. A current path may thereby be established or interrupted from terminal 106 to terminal 108 and through contactor 100 when movable contacts 112, 114 directly contact or separate from the respective stationary contacts 102, 104. As shown in Figure 2, contact bridge 120 may be secured to chassis 130 of contactor 100 via springs 124, which allow contact bridge 120 to be displaced between open and closed states in a direction T of relative movement.

[0036] As previously mentioned, during a switching operation to open the switching device 100, an arc is generated across a gap between the stationary and movable contacts of each contact pair (e.g., pairs of contacts 102, 112 and pairs of contacts 104, 114 shown in FIG. 1). In the open state, each movable contact 112, 114 is separated from its respective stationary contact 102, 104 by a gap in a direction of relative movement T. The width of the gap in the direction T, also referred to as the contact distance, depends on the characteristics of the switching device 100 and the particular application, such as the insulating medium surrounding the contact assembly and high voltage load carried by the switching device 100. The ability of the insulating medium alone to suppress an arc across the contact gap decreases as the contact distance decreases and the high voltage load increases. It would therefore be advantageous to provide an arc quenching system that can effectively extinguish the arc and avoid damaging the switching device 100 for a given contact distance and high voltage load.

[0037] The present invention prevents arcing that could damage the switching device 100 by providing an arc quenching system that diverts the arcing from the contact gap area towards an arc quenching mechanism located close to the gap area but outside the chamber in which the contacts 102, 104, 112, 114 are located to safely extinguish or quench the arc. More specifically, as described in the following embodiments, the arc quenching system is based on the concept of providing an arc blow magnetic unit that can generate a permanent magnetic field in the gap area of ​​each contact pair to extend the arc path along the arc path towards a dedicated arc quenching unit located outside the area of ​​the contact assemblies 102, 112, 104, 114 to extinguish the diverted arc.

[0038] 1, the contactor 100 has an arc elimination system including a number of arc blow magnetic units 140, 150, each corresponding to a respective contact pair for magnetically blowing an arc discharge generated between the stationary contact and the moving contact of the contact pair. In particular, the arc elimination system has a first arc blow magnetic unit 140 for magnetically blowing an arc discharge generated across a gap between the first pair of contacts 102, 112 away from the respective contact gap, and a second arc blow magnetic unit 150 for magnetically blowing an arc discharge generated across a gap between the second pair of contacts 104, 114 away from the respective contact gap. In other words, in this configuration, the arc elimination system includes a number of arc blow magnetic units corresponding to the number of contact pairs to be protected from arc discharge.

[0039] The arc-blow magnetic units 140, 150 are fixed to the contactor chassis 130, spaced apart along the longitudinal direction L of the contact assembly, and aligned with the respective associated contact pairs. Each of the plurality of arc-blow magnetic units 140, 150 is configured to generate a permanent magnetic field in a gap region of a corresponding contact pair, with magnetic field lines in the gap region generally oriented along a direction perpendicular to both the longitudinal direction L and the lateral direction T.

[0040] In detail, the first arc-blow magnetic unit 140 includes a first magnet 142 disposed on one side of the contact pair 102, 112 and the contact assembly 102, 112, 104, 114 (i.e., the rear side of the switching device in FIG. 1 ) and a second magnet 144 disposed opposite the first magnet 142 with respect to a symmetry plane parallel to the line AA′ shown in FIG. 1 and disposed on the opposite side of the contact pair 102, 112 and the contact assembly 102, 112, 104, 114 (i.e., the front side of the switching device in FIG. 1 ). The first arc-blow magnetic unit 140 is disposed in alignment with the first contact pair 102, 112 (i.e., does not overlap the second contact pair 104, 114) and generates a first magnetic field having magnetic field lines along a predetermined magnetic field direction (i.e., parallel to the predetermined magnetic field direction) in the gap region of the first contact pair 102, 112.

[0041] The first magnet 142 and the second magnet 144 are preferably permanent magnets, however, other types of magnets may be used depending on the application, such as magnets formed from soft magnetic materials.

[0042] The first permanent magnet 142 and the second permanent magnet 144 are positioned with their front faces facing each other such that the magnetic flux lines in the gap region flow along a predetermined magnetic field direction from the front face of the first permanent magnet 142 to the front face of the second permanent magnet 144. In addition, the first permanent magnet 142 and the second permanent magnet 144 are positioned at substantially the same distance from the chassis 130 and oriented parallel to each other with opposite polarizations selected to produce a magnetic field in the region around the gap between the stationary contact 102 and the movable contact 112 having magnetic field lines substantially aligned along a direction transverse to both the longitudinal direction L and the direction of relative movement T. In addition, the dimensions of the first permanent magnet 142 and the second permanent magnet 144 are preferably selected to produce a substantially uniform magnetic field across the gap region of each contact pair 102, 112. The magnetic strength of the first permanent magnet 142 and the second permanent magnet 144 depends on the strength of the desired arc blow magnetic effect and, therefore, the particular application and characteristics of the contactor 100 .

[0043] If the associated contact pairs have similar characteristics, such as similar contact distances and arcing strengths, the second arc blow magnetic unit 150 will have similar structural and magnetic features as described above for the first arc blow magnetic unit 140 to generate parallel magnetic fields of approximately the same strength. However, the first arc blow magnetic unit 140 and the second arc blow magnetic unit 150 are separate and independent units in the sense that they do not share any features with each other to generate their respective magnetic fields. In particular, the second arc blow magnetic unit 150 includes a first magnet 152 arranged on one side of the contact pairs 104, 114 and the contact assemblies 102, 112, 104, 114 (i.e., the rear side of the switching device in FIG. 1), and a second magnet 154 arranged opposite the first magnet 152 with respect to a plane of symmetry parallel to line AA' shown in FIG. 1 and arranged on the opposite side of the contact pairs 104, 114 and the contact assemblies 102, 112, 104, 114 (i.e., the front side of the switching device in FIG. 1). The second arc blow magnetic unit 150 is thereby aligned with the second contact pair 104, 114 (and does not overlap the first contact pair 102, 112) to generate a second magnetic field having magnetic field lines along (i.e., parallel to) the predetermined magnetic field direction within the gap area of ​​the second contact pair 104, 114.

[0044] In addition, the first arc blow magnetic unit 140 includes a flux frame 146 to which the first permanent magnet 142 and the second permanent magnet 144 are attached, and the flux frame 146 also serves as a support for positioning the first permanent magnet 142 and the second permanent magnet 144 on the contactor chassis 130.

[0045] Similarly, the second arc blow magnetic unit 150 also includes a flux frame 156, which carries the first permanent magnet 152 and the second permanent magnet 154 and is mounted to the contactor chassis 130. Each of the flux frames 146, 156 provides a respective flux path for the magnetic field lines flowing from the rear face of the respective second permanent magnet 144, 154 to the rear face of the respective first permanent magnet 142, 152. The flux frames 146, 156 are preferably U-shaped plates with a central flat area configured to facilitate mounting the arc blow magnetic units 140, 150 to the contactor chassis 130, with left and right arms extending perpendicularly from the central plate (i.e., away from the chassis 130 towards the terminals 106, 108) such that the first permanent magnet 142 and the second permanent magnet 146 are mounted in a parallel orientation relative to each other and parallel to the direction of the relative lateral movement T. The left and right arms of the U-shaped flux frames 146, 156 have lengths suitable to position the respective first and second permanent magnets in alignment with the gap regions of the respective contact pairs 102, 112 and 104, 114 when the flux frames are mounted to the chassis 130. As will be described below, the magnetic polarizations of the first and second permanent magnets 142, 144 are selected such that the resulting magnetic field lines are directed from the first permanent magnet 142 to the second permanent magnet 144 within the gap region and follow an orientation determined for the preferred electrical polarity of the stationary contacts 102 (corresponding to the electrical polarity of the terminals 106).

[0046] 1, the arc quenching system further includes a plurality of arc quenching units 160, 170, i.e., the same number as the contact pairs. Each of the arc quenching units 160, 170 is disposed corresponding to a respective contact pair, i.e., pairs 102, 112 and 104, 114, for receiving and quenching an arc discharge generated between the stationary contact and the moving contact of the associated contact pair and independently deflected by the arc blow magnetic unit 140, 150. More specifically, a first arc quenching unit 160 is disposed on a side of the contact assembly 102, 104, 112, 114 corresponding to the first contact pair 102, 112 and the first arc blow magnetic unit 140. A second arc quenching unit 170 associated with the second contact pair 104, 114 is disposed on the opposite side of the contact assemblies 102, 104, 112, 114 corresponding to the second contact pair 104, 114 and the second arc blow magnetic unit 150. Because both arc quenching units 160, 170 are provided on the sides of the contact assemblies 102, 104, 112, 114 (i.e., outside the area in which the contact assemblies 102, 104, 112, 114 are disposed), the arc quenching system can be easily retrofitted to existing switching devices since there is no need to modify the spacing between switching device terminals, contact bridge dimensions, etc. to accommodate the arc quenching units in close proximity to the respective contact pairs.

[0047] To direct the arc discharge generated at a contact pair, e.g., contact pair 102, 112, towards the respectively located arc quenching unit, e.g., arc quenching unit 160, the relative polarization of the first permanent magnet 142 and the second permanent magnet 144 of each arc blow magnetic unit 140 is selected corresponding to the electrical polarity of the contactor terminals 106, 108 to set a preferred direction of the generated magnetic blow effect that deflects the arc discharge generated during the opening operation of the contacts 102, 112 towards the arc quenching unit 160. More specifically, the electrical polarity of the contactor terminals 106, 108 determines the direction of the current flowing across the contactor 100 and the pair of contacts 102, 112 in the closed state, which is the same direction as the arc discharge generated across the contact pair 102, 112 during the switching operation to open the contactor 100. The direction of the arc discharge and the orientation of the magnetic field lines generated by the first permanent magnet 142 and the second permanent magnet 144 across the gap region determine the direction of the Lorentz force applied to the charge of the arc current. Therefore, it is sufficient to provide a single arc quenching unit for each contact pair, close to the contact pair and located in the direction of the generated Lorentz force. Thus, by correlating the polarizations of the first permanent magnet 142 and the second permanent magnet 144 according to their electrical polarity and preferentially connecting them to the corresponding stationary contacts 102 (or terminals 106) of the contactor 100, it is ensured that the magnetic blow effect generated by the arc blow magnetic unit 140 extends and diverts the arc path towards the respective arc quenching unit 150 located in particular in the magnetic blow direction.

[0048] 1, when the terminals 106, 108 are set to connect to positive and negative potentials, respectively, the direction of the arc current in the contact pair 102, 112 is generally upward. Thus, the polarization of the first permanent magnet 142 and the second permanent magnet 144 of the first arc-blow magnetic unit 140 is selected such that the magnetic field lines are directed from the first permanent magnet 142 to the second permanent magnet 144 across the gap region between the contacts 102, 112. As a result, the arc discharge generated in the gap region during the switching operation to open the contactor 100 is deflected toward the arc quenching unit 160 by the generated Lorentz force.

[0049] For the contact pair 104, 114 connected to the negative terminal 108, the arc current generated during the switching operation to open the contactor 100 is directed downwards and towards the arc elimination unit 170 arranged to the left of the contact pair 104, 114. In this case, the polarization of the first permanent magnet 152 and the second permanent magnet 154 of the second arc blow magnetic unit 150 is selected so that the magnetic field lines are directed from the first permanent magnet 152 to the second permanent magnet 154 across the gap area between the contacts 104, 114, i.e. have the same relative polarization as the arc blow magnetic unit 140. For example, the first permanent magnet 142 may be oriented with its front surface corresponding to the north pole relative to the second permanent magnet 144, and the front surface of the second permanent magnet 144 corresponding to the south pole. As a result, the arc discharge generated in the gap area of ​​the contact pair 104, 114 is deflected to the left, i.e. towards the arc elimination unit 170, by the generated Lorentz force.

[0050] Thus, the arc quenching system according to the principles of the present invention enhances arc suppression in direct correlation with the preferential mode of operation of the switching device (i.e., the preferred electrical polarity of the stationary contacts). This is because arcs generated at a particular contact pair are magnetically blown toward a dedicated arc chute that is located in an area outside the contact assembly and positioned relative to the direction of the Lorentz force generated for one particular direction of the arc to capture the magnetically blown arc. As a result, in addition to the benefits provided by magnetically assisted arc quenching, the number of arc chutes provided in the switching device can be minimized since only one arc chute per contact pair is required to receive and extinguish the arcs generated at each contact pair. The arc quenching system thus allows for a reduction in the component count, overall size, and associated manufacturing costs of the switching device by minimizing the polarity compromises imposed on the switching device terminals.

[0051] The first and second arc quenching units 160, 170 may each be an arc chute having multiple arc quenching elements, such as flat split blades or fins, arranged parallel to each other in close proximity to divide the voltage of the arc captured in the arc chute. As shown in FIG. 1, the first and second arc quenching units 160, 170 may each be arranged to have parallel split blades oriented transverse to the direction T of relative movement.

[0052] In addition, as shown in FIG. 7, one of the split blades of the first arc quenching unit 160 is preferably electrically connected to the terminal 106 of the contactor 100 and remains at the same potential. The contact terminal 106 is preferably connected to a high voltage potential V2 through a load 180. For example, a high voltage potential V2 of 225V and a load of 0.2Ω can be used, with the contact bridge 120 being maintained at a potential V1 of 0V. However, these are merely exemplary values ​​and should not be considered as limiting the invention. Similarly, one of the split blades of the second arc quenching unit 170 is electrically connected to the terminal 108 of the contactor 100. By electrically connecting the lower split blades of the arc quenching units 160, 170 to the same potential as the corresponding terminals 106, 108, respectively, the split blades of the first arc quenching unit 160 and the second arc quenching unit 170 can prevent an increase in arcing between the stationary contacts 102, 104 and the movable contacts 112, 114 during an opening operation due to their proximity to the respective contact pairs 102, 112 and 104, 114.

[0053] The electrical connection between the split blades of the first arc quenching unit 160 and the second arc quenching unit 170 and the contactor terminals 106, 108 can be made via conductive elements such as stripes 164, 174 or wires made of a conductive material. The conductive elements 164, 174 are provided to maintain each split blade at the same potential as the terminal to which it is connected, and thus are different from the guide runners used in conventional arc chutes to guide and direct the arc discharge directly to the arc chute.

[0054] 1, the arc quenching system comprises one arc blow magnetic unit per contact pair (i.e., a first arc blow magnetic unit 140 associated with contact pair 102, 112 and a second arc blow magnetic unit 150 associated with contact pair 104, 114), and divides the arrangement of the arc quenching units 160, 170 into left and right sides of the contact assembly 102, 104, 112, 114, i.e., the left and right sides of the corresponding switching device 100, with respect to a plane of symmetry (not shown) that transversely intersects the intermediate region between the first contact pair 102, 112 and the second contact pair 104, 114 along the direction of relative movement T and transverse to the longitudinal direction L. Thus, as shown in FIG. 1, the arc quenching units 160, 170 are arranged on opposite sides of the electrical switching device 100, spaced apart in the longitudinal direction L.

[0055] In an alternative configuration, the magnetic blow effect can be achieved using a single arc-blow magnetic unit having some features similar to those described with reference to Figure 1, but designed and oriented to produce a magnetic field acting on the gap regions of all or at least two of the contact pairs that form the contact assembly of the switching device, so that the desired magnetic blow effect can be produced in all of the arc columns using the same magnetic field, as described below with reference to Figures 3 and 4.

[0056] Figures 3 and 4 show an arc-blow magnetic unit 210 of an arc quenching system of a switching device 200 according to another embodiment. The structure, operation and relative positions of the terminals 106, 108, stationary contacts 102, 104, movable contacts 112, 114 and conductive bridge 120 of switching device 100 described above with reference to Figures 1 and 2 are the same for switching device 200 of the present embodiment, and therefore a description of these features of switching device 200 will not be repeated here.

[0057] Referring to FIG. 3, the arc blow magnetic unit 210 includes a first permanent magnet 212 arranged on one side of the first contact pair 102, 112, which is the side of the contact assembly formed by the first contact pair 102, 112 and the second contact pair 104, 114 (i.e., the left side with respect to the front side of the contact assembly 102, 112, 104, 114 shown in FIG. 3), and a second permanent magnet 214 arranged on the opposite side of the contact assembly 102, 112, 104, 114, directly opposite the first permanent magnet 212 in the longitudinal direction L (i.e., the right side with respect to the front side of the contact assembly 102, 112, 104, 114, which corresponds to the positive direction of the Y-axis shown in FIG. 3). The first permanent magnet 212 and the second permanent magnet 214 are positioned approximately the same distance from a chassis (not shown) of the switching device and are oriented parallel to each other with opposite polarization to produce a magnetic field having magnetic field lines extending across the area between the contact pairs 102, 112 and 104, 114, at least in the area around the gap between the stationary contacts 102, 104 and the movable contacts 112, 114, and thus approximately aligned along a direction parallel to the longitudinal direction L and transverse to the direction of relative movement T. The dimensions and magnetic strength of the first permanent magnet 212 and the second permanent magnet 214 are selected to produce a substantially uniform magnetic field across the gap areas of both the first contact pair 102, 112 and the second contact pair 104, 114. Additionally, the magnetic strength of the first permanent magnet 212 and the second permanent magnet 214 are also selected based on the desired strength of the arc blow magnetic effect and the distance between the contact pairs 102, 112 and 104, 114, and thus the particular application and characteristics of the switching device 200.

[0058] As in the previous embodiment, the arc-blow magnetic unit 210 includes a flux frame 230 to which the first and second permanent magnets 214 are attached, which also serves as a support for arranging the first and second permanent magnets 212 and 214 on the contactor chassis 130. The flux frame 230 is a U-shaped plate with a central flat area designed to extend in the longitudinal direction L and with a length suitable to cover the first pair of stationary contacts 102 and movable contacts 112 and the second pair of stationary contacts 104 and movable contacts 114, and therefore it is preferred to arrange the first and second permanent magnets 212 and 214 on each side of the contact assemblies 102, 112, 104, 114. The flux frame 230 further includes a left arm 232 and a right arm 234 extending toward the front side of the contact assemblies 102, 112, 104, 114 (i.e., toward the positive direction of the X-axis in FIG. 3 ), with the first permanent magnet 212 and the second permanent magnet 214 mounted on the left arm 232 and right arm 234, respectively, in a parallel orientation relative to one another, which orientation is also parallel to the direction of relative lateral movement T and transverse to the longitudinal direction L. The left arm 232 and right arm 234 of the U-shaped flux frame 230 have a length suitable to position the permanent magnets 212, 214 aligned in the gap regions of both the first pair of stationary and movable contacts 102 and 112 and the second pair of stationary and movable contacts 104 and 114.

[0059] As shown in FIG. 4, the first permanent magnet 212 and the second permanent magnet 214 are selected to have relative polarizations to create magnetic field lines (B mag) is directed from the first permanent magnet 212 to the second permanent magnet 214 along the region in which the contact assemblies 102, 112, 104, 114 are located. The magnetic field generated by the arc blow magnetic unit 210, together with the magnetic fields generated by the currents flowing through the stationary and movable contacts of the contact pairs, produces a total electromagnetic force F that is generally directed away from the center of the gap of each contact pair. The resultant electromagnetic force F acts on the charges of the arc generated between the contacts, causing the arc column to elongate and deform in the direction of the resultant electromagnetic force F. 1 and 2, the orientation of the resultant magnetic blow effect, i.e., whether the arc column is deflected toward the front or rear of the contact assemblies 102, 112, 104, 114 as in the configuration of FIG 3, still correlates to the direction of the arcing current and, therefore, to the electrical polarity of the terminals 106, 108 (which corresponds to the electrical polarity of the stationary contacts 102, 104). For example, if the terminals 106, 108 are configured to connect to positive and negative potentials, respectively, the direction of the arcing current is upward between the first pair of contacts 102, 112 and downward between the second pair of contacts 104, 114, as shown in FIG 4.

[0060] Thus, the relative polarization between the first and second permanent magnets 212, 214 of the arc-blowing magnetic unit 210 can be selected such that magnetic field lines are directed from the first permanent magnet 212 to the second permanent magnet 214 across the gap region between the stationary and movable contacts 102, 112 of the first contact pair and across the gap region between the stationary and movable contacts 104, 114 of the second contact pair. As a result, the arc columns generated at the contact pairs 102, 112 and 104, 114 are extended and deflected (magnetically blown) in opposite directions due to the action of symmetrically opposing Lorentz forces.

[0061] As described with reference to the embodiment shown in Figures 5 and 6, the arc column magnetically blown by the arc-blowing magnetic unit 210 can be contained and extinguished in respective arc quenching units associated with each contact pair and arranged corresponding to each contact pair and terminal polarity.

[0062] 5 is a perspective view illustrating an arc quenching system and switching device 200 according to an embodiment in which the arc quenching system includes an arc blow magnetic unit 210. Additionally, the arc quenching system includes a plurality of arc quenching units 240, 250 corresponding to each of the terminals 106, 108 and the associated contact pairs 102, 112 and 104, 114, respectively. The first arc quenching unit 240 and the second arc quenching unit 250 are disposed proximate to the respective contact pairs 102, 112 and 104, 114 in the direction of the magnetic blow generated by the arc blow magnetic unit 210 in the gap regions of the respective contact pairs 102, 112 and 104, 114, the direction of the magnetic blow being determined by the electrical polarity of the respective terminals 106, 108.

[0063] 3 and 4, for a polarity configuration in which the terminal 106 is positive with respect to the polarity of the terminal 108, and the first and second magnets 212 and 214 are magnetically polarized to produce magnetic field lines directed from the first magnet 212 to the second magnet 214, the arc quenching system comprises a first arc quenching unit 240 associated with the first contact pair of the stationary and movable contacts 102 and 112, the first arc quenching unit 240 being disposed on the front side of the contact assemblies 102, 104, 112, 114 (i.e., in the positive direction of the X-axis shown in FIG. 6) corresponding to the gap region between the stationary and movable contacts 102 and 112 to receive and quench the arc discharge generated across the gap of the first contact pair 102, 112 during an opening operation. The arc discharge is blown from the contact gap region toward the first arc quenching unit 240 by a resultant Lorentz force generated by the arc blow magnetic unit 210.

[0064] In addition, the arc quenching system includes a second arc quenching unit 250 associated with the second pair of stationary and movable contacts 104, 114, the second arc quenching unit 250 being positioned in a direction of an arc current generated across the gap area of ​​the second contact pair 104, 114 during an opening operation, corresponding to the gap area between the stationary and movable contacts 104, 114. Thus, the direction of the Lorentz force acting on the arc discharge between the second contact pair 104, 114 is reversed relative to the Lorentz force generated across the gap region of the first contact pair 102, 112 (the direction of the arc current is reversed due to the opposite polarity of the second terminal 108), and the second arc quenching unit 250 is disposed on the rear side of the contact assembly 102, 104, 112, 114 and the contact pairs 104, 114 (i.e., opposite the side on which the first arc quenching unit 240 is disposed) to receive the arc discharge generated across this gap region of the second contact pair 104, 114 during the opening operation, and this arc discharge is magnetically blown by the arc blow magnetic unit 210 towards the rear side of the contact assembly 102, 104, 112, 114.

[0065] The arc quenching system of the present configuration therefore divides the arrangement of the arc quenching units 240, 250 between the front and rear sides of the contact assemblies 102, 104, 112, 114, i.e., between the front and rear sides of the corresponding switching device 200, with respect to a plane of symmetry parallel to the longitudinal direction L of the electrical switching device 200 (which in the illustrated configuration is generally aligned with the predetermined magnetic field direction) that intersects both contact pairs 102, 112 and 104, 114 along the direction of relative movement T.

[0066] As a result, the arc quenching system of the present embodiment provides a switching device 200 with enhanced arc suppression and compact size because only one arc quenching unit is used per contact pair (or terminal) of the switching device 200, and no additional space is required between the stationary contacts and the respective terminals to accommodate the arc quenching mechanism. The arc quenching system can also be advantageously used and easily implemented in existing switching devices because the arc blow magnetic unit 210 and the arc quenching units 240, 250 can be simply accommodated in the areas around the respective contact pairs and terminals, and therefore no modification of the structural features of the switching device, the driving features of the contact bridges, etc. is required to increase the spacing between the terminals and / or between the stationary and movable contacts to accommodate the arc chutes within the spaces between the contact pairs and / or terminals. The use of a single arc-blowing magnetic unit 210 to deflect arcing from both the first pair of contacts 102, 112 and the second pair of contacts 104, 114 also has the advantage of reducing the number of magnetic components, assembly steps, and therefore overall manufacturing costs. This configuration of the arc quenching system can also be easily implemented in switching devices having three or more terminals arranged longitudinally along the direction L by providing respective arc quenching units for each of the contact pairs located at the same front or rear side of the contact assembly depending on the polarity of each switching device terminal that affects the direction of the resultant Lorentz force generated at each individual contact pair.

[0067] Similar to the embodiment described with reference to Figures 1 and 2, the first arc quenching unit 240 and the second arc quenching unit 250 may be arc chutes having multiple arc quenching elements 242, 252, such as split blades or fins, respectively. Figure 5 shows a configuration in which the split blades 242, 252 of the first arc quenching unit 240 and the second arc quenching unit 250 are arranged parallel to each other and transverse to the direction T of relative movement that coincides with the direction of the gap between the stationary contact and the movable contact of each contact pair 102, 112 and 104, 114. In addition, the split blades 242, 252 of the first arc quenching unit 240 and the second arc quenching unit 250 are designed as L-shaped flat plates, allowing the split blades to be placed close to the respective contact pairs, minimizing the distance to the contact gap. For example, as shown in Figures 5 and 6, the L-shaped split blade 242 of the first arc quenching unit 240 is arranged with the short leg of the L oriented to protrude toward the gap between the contacts 102, 112, thereby shortening the distance that the arc discharge must be deflected by the arc magnetic blow unit 210. The long leg of the L-shaped split blade 242 is arranged to extend toward the center of the arc quenching system along the longitudinal direction L, thereby realizing a compact arc quenching system. As a result, the distance from the gap region to the L-shaped split blade 242 of the arc quenching unit 240 can be shortened, and the magnetically blown arc discharge can be contained at an earlier stage compared to the square split blade as described with reference to Figures 1 and 2. Furthermore, the L-shaped design allows a large portion of the arc discharge to be extinguished over the long leg of the L and therefore at a safer distance from the stationary contact 102 and the movable contact 112. The L-shaped design and orientation of the split blades also compensate for the reduction in magnetic field strength caused by the increased distance between the first permanent magnet 212 and the second permanent magnet 214 of the arc blow magnetic unit 210 in this embodiment compared to the distance of the magnets of the arc blow magnetic unit provided on a single contact pair, such as the arc blow magnetic units 140, 150 of the previous embodiment, which use permanent magnets of similar strength. Similarly, the split blades 252 of the second arc quenching unit 250 are oriented with respect to the second contact pair 104, 114 such that the short leg of the L is located close to and protrudes toward the gap area between the stationary contact 104 and the movable contact 114. The long leg of the split blade 252 is positioned to extend along the longitudinal direction L toward the center of the arc quenching system. Similar to the embodiment of FIG. 1, each of the first arc quenching unit 240 and the second arc quenching unit 250 can have one split blade directly connected to the contactor terminals 106, 108, respectively, via a conductive element, such as stripes 244, 254 formed from a conductive material or the like, to maintain the respective split blades at the potential of the respective terminals 106, 108. For example, in the configuration of FIG. 5, the bottommost blade of the first arc quenching unit 240 (i.e., the blade closest to the underside of the terminal 106) is electrically connected to the terminal 106. Similarly, the bottommost blade of the second arc quenching unit 250 is electrically connected to the terminal 108. As previously mentioned, conductive elements 244, 254 are provided to maintain each arc quenching element at the same potential as the terminal to which it is electrically connected, and therefore do not function as guide runners used in conventional arc chutes.

[0068] It should be noted that the L-shape and orientation of the split blades 242, 252 described above with respect to the embodiment of FIGS. 5-7 may also be implemented in the configuration of the arc extinguishing system described with reference to FIGS.

[0069] It is further noted that the shape, size, and number of the split blades of the arc quenching units described in the above embodiments, as well as their distance from the associated contact pairs, may vary depending on the particular characteristics of the electrical switching device (e.g., separation gap between stationary and movable contacts, operating voltage, etc.) and therefore can be advantageously determined and optimized for a particular design and application of the electrical switching device, e.g., based on simulation analysis and / or experimentation.

[0070] In summary, the arc quenching system according to the principles of the present invention uses the directionality of the magnetic blow effect exerted by the polarity of the switching device terminals to reduce the number of arc quenching units to one per contact pair (or terminal), thereby providing a switching device with enhanced arc suppression and compact size. As a result, there is no need to provide additional space between the stationary contacts, contact pairs, and / or respective terminals to accommodate the arc quenching mechanism. The arc quenching system of the present invention can be advantageously used and easily implemented in existing switching devices, since the arc quenching system can be simply accommodated around the respective contact pairs and terminals and fixed to the chassis of the existing switching device without the need to modify the structural features of the switching device, such as the spacing between the terminals of the switching device, between the stationary contacts and the moving contacts, the driving mechanism of the contact bridge, etc. Furthermore, the configuration of the arc quenching system described above with reference to Figures 3 to 6 can be easily implemented and adapted to switching devices having one or more terminals arranged longitudinally along direction L by providing respective arc quenching units to be located at the front or rear of the contact assembly corresponding to each of the contact pairs depending on the polarity of each switching device terminal and the resultant Lorentz force generated by the arc blow magnetic unit at each individual contact pair.

[0071] While certain features of the exemplary embodiments above have been described with reference to the figures and using relative terms such as "front", "back", "left", "right", "top", "bottom", etc., it should be understood that these terms are defined with reference to the coordinate system shown in each figure. Unless otherwise specified in the description, the terms "front", "right", and "upper" are used to describe features that are located in the positive directions of the X, Y, and Z coordinate axes relative to other features of the switching device. Nevertheless, it should be understood that these terms are used solely for the purpose of facilitating the description of the respective features and how they are positioned / oriented relative to one another, and should not be construed as limiting the claimed invention or any of its components to mounting or use in a particular spatial orientation. Additionally, in the context of this disclosure, phrases such as "along a given direction" should be understood to describe a direction that is generally consistent with or parallel to the "predetermined direction." Additionally, the term "orientation" is used in the context of magnetic flux lines to refer to the direction and orientation of the magnetic flux vector along the magnetic field lines. Finally, although the present invention has been described with respect to electrical switching devices such as contactors and high voltage relays, the principles of the present invention may be advantageously applied to other types of switching equipment in which it may be advantageous to protect against arcing during opening of contact terminals. [Explanation of symbols]

[0072] 100 Switching Devices 102, 104 Static contact 106, 108 Electrical terminal 112, 114 Movable contact 120 Contact Bridge 124 Contact bridge support spring 130 Chassis 140 First Arc Blow Magnetic Unit 142 First permanent magnet 144 Second permanent magnet 146, 156 Flux Frame 150 Second Arc Blow Magnetic Unit 152 First permanent magnet 154 Second permanent magnet 160 First Arc Quenching Unit 170 Second Arc Quenching Unit 164, 174 Electrical Contact Stripes 180 Load V1, V2 potential 200 Switching Devices 210 Arc Blow Magnetic Unit 212 First permanent magnet 214 Second permanent magnet 230 Magnetic flux frame 232, 234 Arms of U-shaped flux frame 240 First Arc Quenching Unit 250 Second Arc Quenching Unit 242, 252 split blade 244, 254 Electrical Contact Stripes

Claims

1. 1. An arc quenching system for suppressing an arc between a contact pair of an electrical switching device, the contact pair having a stationary contact and a movable contact, the movable contact being movable relative to the stationary contact between a closed state in which the movable contact contacts the stationary contact and an open state in which the movable contact is spaced from the stationary contact by a gap in a direction of relative movement between the movable contact and the stationary contact, the arc quenching system comprising: an arc quenching unit provided to the contact pair to quench an arc discharge that occurs when the contact pair is switched from the closed state to the open state; an arc blow magnetic unit configured to generate a magnetic field having magnetic field lines that are aligned with a predetermined magnetic field direction and cross a gap region of the contact pair; Equipped with the arc blow magnetic unit is configured to generate magnetic field lines in a predetermined orientation based on a preferred electrical polarity of the stationary contacts of the contact pair and a position of the arc quenching unit to magnetically blow an arc discharge generated in the gap region of the contact pair toward the arc quenching unit associated with the contact pair; the arc quenching unit includes a plurality of split blades arranged parallel to one another and configured to split a voltage of the arc discharge across the arc quenching unit; the plurality of split blades are a plurality of L-shaped plates oriented such that a short leg of the L projects toward the gap region of an associated pair of contacts; The plurality of split blades are further disposed transversely to the direction of the relative movement. Arc quenching system.

2. the contact pairs include a first contact pair and a second contact pair disposed adjacent to one another along a longitudinal direction transverse to the direction of the relative movement; the arc blow magnetic unit is configured to generate the magnetic field having magnetic field lines that cross the gap regions of the first and second contact pairs along the predetermined magnetic field direction; the arc blow magnetic unit is configured to be arranged with respect to the first and second contact pairs such that the predetermined magnetic field direction is parallel to the longitudinal direction; and / or the arc quenching units include a first arc quenching unit configured to be positioned opposite the first contact pair and a second arc quenching unit configured to be positioned opposite the second contact pair, the first arc quenching unit being disposed on one side of a plane of symmetry parallel to the longitudinal direction that intersects the first contact pair and the second contact pair along the direction of the relative movement; 10. The arc quenching system of claim 1.

3. the contact pairs include a first contact pair and a second contact pair disposed adjacent to one another along a longitudinal direction transverse to the direction of the relative movement; The arc blow magnetic unit includes: a first arc blow magnetic unit configured to generate a first magnetic field having magnetic field lines along a first predetermined magnetic field direction in a region of a gap between the first pair of contacts; a second arc blow magnetic unit configured to generate a second magnetic field having magnetic field lines along a second predetermined magnetic field direction in a region of the gap of the second contact pair; the second arc blow magnetic unit is spaced apart from the first arc blow magnetic unit; and / or the arc quenching units include a first arc quenching unit configured to be positioned opposite the first contact pair and a second arc quenching unit configured to be positioned opposite the second contact pair, the first arc quenching unit being disposed on one side of a plane of symmetry between the first contact pair and the second contact pair that is transverse to the longitudinal direction along the direction of the relative movement; 10. The arc quenching system of claim 1.

4. the stationary contacts of the first and second contact pairs have opposite polarities; the second arc quenching unit associated with the second contact pair is located on a side of the symmetry plane opposite to the side on which the first arc quenching unit associated with the first contact pair is located; 3. The arc extinguishing system of claim 2.

5. the stationary contacts of the first and second contact pairs have opposite polarities; the second arc quenching unit associated with the second contact pair is located on a side of the symmetry plane opposite to the side on which the first arc quenching unit associated with the first contact pair is located; 4. The arc extinguishing system of claim 3.

6. the arc quenching unit includes an electrical contact element configured to provide a direct electrical connection between the split blade and a terminal of the switching device to which the stationary contact of the contact pair is attached; and / or The arc quenching unit is located opposite the gap region of the contact pair.

10. The arc quenching system of claim 1.

7. The arc blow magnetic unit includes a first permanent magnet and a second permanent magnet; the first permanent magnet and the second permanent magnet are arranged with their front faces facing each other such that magnetic flux lines in the gap area of ​​an associated contact pair flow from the front face of the first permanent magnet to the front face of the second permanent magnet along the predetermined magnetic field direction.

10. The arc quenching system of claim 1.

8. the arc blow magnetic unit further includes a flux frame to which the first permanent magnet and the second permanent magnet are attached; the flux frame is configured to provide a flux path for magnetic field lines flowing from a rear surface of the second permanent magnet to a rear surface of the first permanent magnet; 8. The arc extinguishing system of claim 7.

9. the flux frame is a plate having a U-shape defined by a central plate and two extending arms respectively extending from the left and right sides of the central plate; the central plate is configured to mount the flux frame to a chassis of the switching device; the first permanent magnet and the second permanent magnet are each disposed on the extension arm of the flux frame at a distance from the central plate adapted to position the first permanent magnet and the second permanent magnet in alignment with the gap region of the contact pair when the flux frame is attached to the chassis of the switching device.

9. The arc extinguishing system of claim 8.

10. the magnetic polarization of the first permanent magnet and the second permanent magnet is selected according to an established orientation of the preferred electrical polarity of the stationary contact such that the resulting magnetic field lines are directed from the first permanent magnet to the second permanent magnet within the gap region of the contact pair.

8. The arc extinguishing system of claim 7.

11. 1. An electrical switching device comprising: a first pair of contacts and a second pair of contacts disposed adjacent to each other along a longitudinal direction of the electrical switching device; each of the first and second contact pairs includes a stationary contact and a movable contact, the movable contact being movable relative to the stationary contact between a closed state in which the movable contact is in contact with the stationary contact and an open state in which the movable contact is spaced apart from the stationary contact by a gap in a direction of relative movement between the movable contact and the stationary contact; The electrical switching device comprises: The arc extinguishing system according to any one of claims 1 to 10, the arc quenching system is positioned in alignment with the first contact pair and the second contact pair such that the arc blow magnetic unit generates the magnetic field having magnetic field lines that cross the gap region of each contact pair along the predetermined magnetic field direction; The arc quenching unit is located opposite each of the contact pairs. Electrical switching devices.

12. a first terminal and a second terminal connected to the stationary contacts of the first and second contact pairs, respectively; the first terminal and the second terminal are configured to electrically connect the switching device to an external potential or to a load circuit according to a preferred polarity of operation of the switching device.

12. The electrical switching device of claim 11.

13. The electrical switching device of claim 11 , wherein the switching device is a contactor or a high voltage relay.

14. the electrical switching device and the arc quenching system are free of guide runners for guiding the arc discharge between the first contact pair and the second contact pair directly toward the associated arc quenching unit; 12. The electrical switching device of claim 11.

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