Switching pole for electrical systems

Abstract

The present disclosure relates to a switching pole for an electrical system. A switching pole for a low voltage switching device, comprising: an insulating housing defining an interior space having a contact region and an arc extinction region of the switching pole; a first pole terminal and a second pole terminal couplable with corresponding line conductors of a power line; a stationary contact assembly and a movable contact assembly positioned in the contact region, the stationary contact assembly and the movable contact assembly comprising a stationary contact and a movable contact respectively couplable or separable from each other.

Description

Technical Field

[0001] This invention relates to a switching electrode suitable for use in a switchgear installed in a low-voltage electrical system. The invention also relates to a switchgear comprising one or more of the aforementioned switching electrodes.

[0002] Low-voltage switchgear, such as circuit breakers, disconnectors, contactors, etc., includes one or more switching poles, each of which includes electrical contacts that can be coupled and disconnected from each other. Background Technology

[0003] As is well known, during the opening and closing operation of a switchgear, in the disconnected state, especially under stress conditions (e.g., in the presence of overload current or short-circuit current), an electric arc can be generated between the electrical contacts of the switch poles.

[0004] To interrupt the current flowing along the switching pole, such arcing must be extinguished as quickly as possible. Therefore, for each switching pole, the switching device generally includes an arc chamber containing multiple arc-extinguishing elements positioned near the electrical contacts and designed to extinguish any arcs that may form between them. Unfortunately, the arc-extinguishing effect exerted by the arc-extinguishing elements is not always uniform and effective, which can lead to a decrease in arc-extinguishing performance and the re-ignition of the arc between the electrical contacts of the switching pole. Furthermore, it has been observed that during the opening and closing operation of the switching device, the arc can sometimes break down to other conductive parts of the switching pole located outside the arc chamber. Clearly, components affected by these phenomena can suffer severe damage because they are generally not designed to withstand high electrical and thermal stresses.

[0005] The aforementioned problems become even more critical in the context of modern power distribution networks, as switching equipment often needs to operate at relatively high operating voltages (e.g., up to 2.0 kV to 2.5 kV AC or DC). Consequently, during the opening and closing operations of the switching equipment, an electric arc with enormous energy can be generated between the disconnected electrical contacts. Summary of the Invention

[0006] The main objective of this invention is to provide a switching electrode for low-voltage switchgear that allows for overcoming or mitigating the aforementioned disadvantages.

[0007] In particular, the present invention aims to provide a switching electrode in which an electric arc generated between electrical contacts in the disconnected state during the opening and closing operation of a switching device is effectively confined within the arc-extinguishing region of the switching electrode.

[0008] Another object of the present invention is to provide a switching electrode in which arcing is prevented or significantly reduced in the portion of the electrode outside the arc-extinguishing region.

[0009] Another object of the present invention is to provide a switch electrode that is reliable in operation and relatively easy and inexpensive to manufacture at the industrial level.

[0010] According to the present invention, the above-mentioned objects and purposes, as well as other objects that will become apparent from the following description and drawings, are achieved by the switching poles for a low-voltage switchgear according to claim 1 and related dependent claims.

[0011] According to the present invention, the switching electrode includes an insulating housing defining the internal space of the switching electrode, a first terminal and a second terminal that can be coupled to a corresponding line conductor of a power line.

[0012] According to the present invention, the switching electrode includes a fixed contact assembly comprising a plurality of fixed electrical contacts electrically connected to a first terminal. The fixed electrical contacts include one or more first fixed contacts and one or more second fixed contacts spaced apart from and electrically insulated from the first fixed contacts.

[0013] According to the present invention, the switch electrode includes a movable contact assembly comprising a plurality of movable electrical contacts electrically connected to a second terminal. The movable electrical contacts include one or more first movable contacts and one or more second movable contacts.

[0014] The movable contact assembly is reversibly movable about a rotation axis, such that during the operation of the switching poles, as the movable contact assembly moves about the rotation axis, the first movable contact can be coupled to or disengaged from the first fixed contact, and the second movable contact can be coupled to or disengaged from the second fixed contact.

[0015] The movable contact assembly also includes a support structure for the movable contact of the movable contact assembly.

[0016] Preferably, the movable contact of the movable contact assembly is mounted on a conductive contact, which is electrically connected to the second terminal and hinged to the support structure.

[0017] According to the present invention, the movable contact assembly includes an insulating cover that at least partially covers one or more conductive portions of the movable contact assembly.

[0018] During operation of the switching electrode, the insulating cover moves together with the support structure about the rotation axis of the movable contact assembly.

[0019] However, during the operation of the switching poles, the insulating cover can move relative to the support structure as the movable contact assembly moves about its axis of rotation.

[0020] Preferably, the insulating cover is reversibly movable between a first shielding position and a second shielding position. In the first shielding position, the insulating cover is not inserted between the electrical contacts of the switch poles. In the second shielding position, the insulating cover has a shielding portion inserted between one or more first fixed contacts of the fixed contact assembly and one or more first movable contacts of the movable contact assembly.

[0021] Preferably, during the switching operation, the insulating cover moves from the first shielding position to the second shielding position.

[0022] Preferably, when the insulating cover is in the second shielding position, the shielding portion of the insulating cover covers one or more first movable contacts of the movable contact assembly.

[0023] During the switching operation of the switch pole, the insulating cover reaches the second shielding position after the first movable contact of the movable contact assembly separates from the first fixed contact of the fixed contact assembly.

[0024] Preferably, the insulating cover is hinged to the support structure at a hinge axis parallel to the rotation axis of the movable contact assembly.

[0025] According to some embodiments of the invention, the movable contact assembly includes an insulating partition that protrudes toward the fixed contact assembly and is at least partially slidably inserted into a receiving cavity defined by an insulating housing.

[0026] An insulating partition is inserted between one or more first fixed contacts and one or more second fixed contacts of a fixed contact assembly, and is also inserted between one or more first movable contacts and one or more second movable contacts of a movable contact assembly.

[0027] Preferably, the insulating partition is fixed to the support structure of the movable contact assembly such that during operation of the switching poles, as the movable contact assembly moves about its axis of rotation, the insulating partition moves together with the support structure.

[0028] Preferably, the insulating partition is positioned in a first gap region between one or more first movable contacts and one or more second movable contacts of the movable contact assembly.

[0029] Preferably, the receiving cavity has an opening for the passage of an insulating partition, the opening being located in a second spacing region between one or more first fixed contacts and one or more second fixed contacts of the fixed contact assembly.

[0030] Preferably, the insulating partition has a free end positioned relative to the movable contact of the movable contact assembly. During operation of the switching pole, as the movable contact assembly moves about the axis of rotation, the free end of the insulating partition is inserted into the receiving cavity and slides along the receiving cavity.

[0031] According to some embodiments of the invention, the insulating partition has a piston portion that slides along a receiving cavity during operation of the switching electrode as the movable contact assembly moves about a rotation axis. During the opening and closing operation of the switching electrode, such a piston portion of the insulating partition causes a pressurized airflow to blow towards one or more second fixed contacts of the fixed contact assembly and one or more second movable contacts of the movable contact assembly.

[0032] Preferably, the piston portion is formed from the L-shaped free end of an insulating diaphragm.

[0033] In another aspect, the present invention relates to a low-voltage switchgear, preferably a circuit breaker, comprising at least one switching pole according to the invention, as described above. Attached Figure Description

[0034] Further features and advantages of the invention will become apparent from the description of preferred, but not exclusive, embodiments of the switching poles according to the invention, which are illustrated by way of example in the accompanying drawings, in which:

[0035] Figure 1 This is a schematic diagram of a switching device including switching electrodes according to the present invention;

[0036] Figure 2 , Figures 2A to 2B , Figures 3 to 5 The structure and operation of the switching electrode according to an embodiment of the present invention are schematically illustrated;

[0037] Figures 6 to 9 The structure and operation of the switching electrode according to another embodiment of the present invention are illustrated schematically;

[0038] Figures 10 to 12 The structure and operation of the switching electrode according to another embodiment of the present invention are illustrated schematically. Detailed Implementation

[0039] Referring to the accompanying drawings, the present invention relates to a switching pole 1 for a low-voltage switchgear 100, such as a circuit breaker, disconnector, contactor, etc. The switchgear 100 is particularly suitable for AC low-voltage electrical systems, and will be described with particular reference to these applications. However, in principle, it can also be used in different types of electrical systems, such as DC low-voltage electrical systems.

[0040] For the purposes of this invention, the term "low voltage" generally refers to operating voltages typically up to 1.0 kV AC and 1.5 kV DC, and for some applications, this voltage can be extended to 2.0 kV AC and 2.5 kV DC.

[0041] According to the present invention, the switching device 100 includes one or more switching poles 1. The number of switching poles can be varied as needed.

[0042] In some embodiments, the switching device 100 may be three-phase and includes three switching poles. However, according to other embodiments of the invention, the switching device may include a different number of switching poles, depending on the number of electrical phases of the circuit in which it must be installed.

[0043] According to the present invention, the switching electrode 1 includes an insulating housing 2, which defines an internal volume comprising a contact region 3 and an arc-extinguishing region 4. Figure 5 , Figure 9 , Figure 12 ).

[0044] Generally, contact region 3 is part of the internal volume of the switching electrode, in which the contact assembly of the switching electrode is arranged and operates. On the other hand, arc extinguishing region 4 is part of the internal volume of the switching electrode, in which an arc extinguishing device is arranged, which is designed to extinguish any arc that may be generated between the electrical contacts of the switching electrode during the breaking operation.

[0045] Contact region 3 and arc extinguishing region 4 are adjacent and fluidly connected to each other.

[0046] Preferably, the arc-extinguishing region 4 is positioned at a higher level relative to the contact region 3, that is, at a proximal position relative to the top side of the contact region 3.

[0047] For clarity, it is hereby stated that the relevant terms used in this disclosure, such as “front,” “rear,” “side,” “upper,” “lower,” “top,” and “bottom,” refer to switch pole 1 in its normal installation state, i.e., in the “vertical” installation mode. Figure 1 ).

[0048] The insulating housing 2 of the switch electrode is formed as an irregularly shaped box having opposing front walls 23 and rear walls 24, opposing side walls 21 and 22, and opposing top walls 25 and bottom walls 26.

[0049] Preferably, the insulating housing 2 is formed by a first half-shield and a second half-shield joined together. Preferably, the top wall 25 is provided with a plurality of openings to allow hot gases to escape from the internal volume of the switching electrode, particularly from the arc-extinguishing region. The insulating housing 2 is made of an electrically insulating material, such as a thermosetting or thermoplastic material.

[0050] According to the present invention, the switch pole 1 includes a first terminal 7 and a second terminal 8, which can be coupled to the corresponding line conductor of the power line.

[0051] In operation, the terminals 7 and 8 are electrically coupled (in a known manner) to the corresponding line conductors of the power line. These line conductors can then be electrically connected to the power source (e.g., a segment of a power transmission or generation system or grid) and the electrical load (e.g., a segment of an electrical system or equipment or grid).

[0052] For clarity, it is hereby stated that, unless otherwise stated or self-evident from the specification or drawings, the terms “coupled,” “disconnected,” or “coupleable” as used in this disclosure refer to the electrical and mechanical coupling / disconnection of various parts.

[0053] Preferably, the extreme terminals 7 and 8 are positioned at the rear wall 24 of the insulating housing of the switching electrode.

[0054] According to the present invention, the switch electrode 1 includes a fixed contact assembly 5 and a movable contact assembly 6 arranged in the contact region 3.

[0055] The fixed contact assembly 5 includes fixed electrical contacts 51 and 52 that are electrically connected to the first terminal 7.

[0056] More specifically, the fixed contact assembly 5 includes one or more first fixed contacts 51 and one or more second fixed contacts 52 spaced apart from and electrically insulated from the fixed contacts 51.

[0057] Therefore, the first fixed contact 51 and the second fixed contact 52 are electrically connected in parallel to the first terminal 7, but they are spaced apart from each other and electrically insulated.

[0058] Preferably, the first fixed contact 51 and the second fixed contact 52 are positioned on the rear wall 24 of the insulating housing of the switch pole.

[0059] Preferably, the first fixed contact 51 and the second fixed contact 52 are arranged at the far end and the near end respectively relative to the arc-extinguishing region 4 of the switching pole.

[0060] The first fixed contact 51 may be formed of a pair of conductive tips disposed on a first conductive base, which is directly coupled to the first terminal 7. Similarly, the second fixed contact 52 may be formed of a pair of conductive tips disposed on a second conductive base electrically connected to the first terminal 7 via other conductive components of the switching electrode. Generally, terminals 7 and 8 and the fixed contact assembly 5 can be implemented according to known types of solutions. In the following description, for the sake of brevity, this component of the switching electrode will only be described with respect to aspects of interest in the invention.

[0061] The movable contact assembly 6 includes movable electrical contacts 61, 62 electrically connected to the second terminal 8. More specifically, the movable contact assembly 6 includes one or more first movable contacts 61 and one or more second movable contacts 62. The first movable contacts 61 can be coupled to or detached from the first fixed contact 51, while the second movable contacts 62 can be coupled to or detached from the second fixed contact 52.

[0062] The movable contact assembly 6 can be reversibly moved about a rotation axis A1, which is preferably perpendicular to the side wall 22 of the insulating housing of the switch pole.

[0063] The movable contact assembly 6 can move around the rotation axis A1 between a first position corresponding to the closed state of the switch pole and a second position corresponding to the open state of the switch pole. In the closed state, current is allowed to flow between the terminals 7 and 8 of the switch pole. In the open state, the current flowing along the switch pole is interrupted.

[0064] The movable contact assembly 6 moves between the first and second positions by rotating about the rotation axis A1 in the opposite direction of rotation.

[0065] The transition of the movable contact assembly 6 from the first position to the second position constitutes the opening operation of the switch pole, while the opposite transition of the movable contact assembly 6 from the second position to the first position constitutes the closing operation of the switch pole.

[0066] Preferably, the first movable contact 61 and the second movable contact 62 are arranged at the far end and the near end respectively relative to the arc-extinguishing region 4 of the switch pole.

[0067] Preferably, the movable electrical contacts 61 and 62 are electrically connected to each other and are electrically connected in parallel to the second terminal 8.

[0068] The movable contact assembly 6 includes a support structure 63 for the movable contacts 61, 62. This support structure can be easily rotated about the axis of rotation A1, and it includes a connecting element 64 that protrudes beyond the insulating housing of the switching pole (preferably from a suitable window on its front wall 23) for connection with a drive mechanism (not shown).

[0069] Preferably, the movable contact assembly 6 includes a conductive contact 65, on which movable contacts 61 and 62 are mounted.

[0070] The conductive contact 65 is electrically connected to the second terminal 8, for example, through a suitable flexible conductor.

[0071] The first movable contact 61 and the second movable contact 62 may be formed by a first pair of conductive fingers and a second pair of conductive fingers, respectively, which protrude from the conductive contact 65.

[0072] Preferably, the conductive contact 65 of the movable contacts 61, 62 that support and electrically connect the switch poles is mounted on the support structure 63 such that during operation of the switch poles, the conductive contact 65 moves together with the support structure about the rotation axis A1.

[0073] Preferably, the conductive contact 65 is hinged to the support structure 63 about a suitable hinge axis, which is conveniently parallel to the rotation axis A1 of the movable contact assembly. Therefore, the conductive contact 65 rotates together with the support structure 63 about the rotation axis A1, and can tilt slightly relative to the support structure as the support structure moves. That is, when the support structure 63 rotates according to a given direction of rotation, the conductive contact 65 can tilt relative to the support structure with opposite rotational movement.

[0074] As described above, in general, switch pole 1 can be in a closed state and an open state during operation, and can perform an opening operation to switch from the closed state to the open state, and perform a closing operation to switch from the open state to the closed state.

[0075] In switch pole 1, the fixed contact assembly 5 and the movable contact assembly 6 are arranged such that when the switch pole is in the closed state, the pole current flows along one or more first fixed contacts 51 and one or more first movable contacts 61. Thus, the electrical contacts 51, 61 form the so-called "main contacts" of the switch pole.

[0076] Furthermore, the fixed contact assembly 5 and the movable contact assembly 6 are arranged such that during the opening and closing of the switching pole, an electric arc is generally formed between the electrical contacts 52 and 62 in the separated state. Therefore, the electrical contacts 52 and 62 form the so-called "arc contacts" of the switching pole.

[0077] In the embodiment shown in the accompanying drawings, during the switching operation, the first movable contact 61 and the second movable contact 62 disengage from the first fixed contact 51 and the second fixed contact 52 according to a specific switching sequence (described below).

[0078] When the movable contact assembly 6 is in the first position (closed state of the switch pole), the first movable contact 61 is coupled to the first fixed contact 51, while the second movable contact 62 is disengaged from the second fixed contact 52.

[0079] In this configuration, the electrode current can flow along the switch electrode between terminals 7 and 8. The electrode current is transmitted entirely through the first movable contact 61 and the first fixed contact 51 (i.e., through the main contact of the switch electrode).

[0080] When the terminals 7 and 8 are short-circuited, no electric arc will be generated between the movable contact assembly 6 and the fixed contact assembly 5.

[0081] During the switching operation, upon initial movement according to a suitable rotational direction about the rotation axis, the movable contact assembly 6 moves from a first position to a first intermediate position, wherein:

[0082] The first movable contact 61 is coupled to the first fixed contact 51;

[0083] The second movable contact 62 is coupled to the second fixed contact 52.

[0084] In this configuration, the electrode current can still flow between terminals 7 and 8. However, the electrode current is shunt between the first current flowing through the first movable contact 61 and the first fixed contact 51 and the second current flowing through the second movable contact 62 and the second fixed contact 52. The magnitudes of the first and second currents depend on the equivalent resistance of the respective conductive paths.

[0085] Since the terminals 7 and 8 are still short-circuited, no electric arc will be generated between the movable contact assembly 6 and the fixed contact assembly 5.

[0086] According to the further movement in the direction of rotation, the movable contact assembly 6 moves from the first intermediate position to the second intermediate position, wherein:

[0087] The first movable contact 61 disengages from the first fixed contact 51;

[0088] The second movable contact 62 is coupled to the second fixed contact 52.

[0089] In this configuration, the electrode current can still flow along the switching electrode between terminals 7 and 8 because the latter remains short-circuited. The electrode current flows entirely through the second movable contact 62 and the second fixed contact 52. No current flows along the first movable contact 61 and the first fixed contact 51 because the latter is disconnected.

[0090] Since the terminals 7 and 8 are still short-circuited, no electric arc will be generated between the movable contact assembly 6 and the fixed contact assembly 5.

[0091] According to the further movement in the direction of rotation, the movable contact assembly 6 moves from the second intermediate position to the aforementioned second position. During this stage of the switching operation, the second movable contact 62 also disengages from the second fixed contact 52 (the first movable contact 61 disengages from the first fixed contact 51). In this case, since the movable electrical contacts 61, 62 are now separated from the corresponding fixed electrical contacts 51, 52, a potential difference is established between the first terminal 7 and the second terminal 8. At any time, the second terminal 8 (and the movable contacts 61, 62) can have a positive voltage polarity, while the first terminal 7 (and the fixed contacts 51, 52) can have a negative voltage polarity, and vice versa. Because the dielectric distance between the movable contacts 61, 62 and the fixed contacts 51, 52 is relatively short, an arc is generated between the movable contact assembly 6 and the fixed contact assembly 5, especially between the second fixed contact 52 and the second movable contact 62 (i.e., between the arc contacts of the switching poles) in the separated state.

[0092] According to different embodiments of the present invention, during the switching operation, the first movable contact 61 and the second movable contact 62 can disengage from the first fixed contact 51 and the second fixed contact 52 according to different switching sequences.

[0093] In the embodiment shown in the accompanying drawings, during the closing operation of the switching poles, the first movable contact 61 and the second movable contact 62 are coupled to the first fixed contact 51 and the second fixed contact 52 according to a specific closing sequence. The closing sequence of the electrical contacts is substantially the reverse of the opening sequence described above.

[0094] However, according to different embodiments of the present invention, during the closing operation of the switch poles, the first movable contact 61 and the second movable contact 62 may be coupled to the first fixed contact 51 and the second fixed contact 52 according to different closing sequences.

[0095] Preferably, the switch electrode 1 includes an arc chamber 40 located in the arc extinguishing region 4, which is conveniently located above the contact region 3 and in fluid communication with the latter.

[0096] The arc chamber 40 includes a plurality of arc-extinguishing elements designed to extinguish any arc that may arise between the electrical contacts of the switching poles when they separate during an opening operation. The arc-extinguishing elements may be parallel arc-extinguishing plates, preferably arranged along a reference plane parallel to the front wall 23 and rear wall 24 and perpendicular to the side wall 22 of the insulating housing 2. The arc-extinguishing plates are preferably located at a subsequent position between the front wall 23 and rear wall 24, increasing in distance from the fixed contact assembly 5. Preferably, the arc-extinguishing plates may be formed of shaped metal or ceramic plates, which may have different sizes and shapes according to known schemes.

[0097] An important aspect of the invention is that the movable contact assembly 6 includes an insulating cover 67 that at least partially covers one or more conductive portions of the movable contact assembly, such as conductive contacts 65.

[0098] An insulating cover 67 is mounted on a support structure 63 such that it moves together with the support structure 63 about a rotation axis A1 during operation of the switching pole.

[0099] However, the insulating cover 67 is arranged so that it can move relative to the support structure 63 during operation of the switching pole.

[0100] For this purpose, the insulating cover 67 is preferably hinged to the support structure 63 about a suitable hinge axis that is conveniently parallel to the rotation axis A1 of the movable contact assembly.

[0101] Figure 2 , Figures 2A to 2B , Figures 3 to 5 The switching electrodes according to an embodiment of the present invention are shown. Figures 3 to 5 The diagram shows the movable contact assembly 6 in different operating positions during the operation of the switching pole.

[0102] According to the embodiment shown in the accompanying drawings, the insulating cover 67 includes lateral legs 69 hinged to the support structure 62 and is arranged such that it covers a portion of the sidewall 22 facing the insulating housing of the conductive contact 65.

[0103] The aforementioned lateral support leg 69 has protrusions 690, which slide into corresponding grooves 220 in the side wall 22 of the switch pole. Figures 2A to 2B ).

[0104] During operation of the switching pole, the movable contact assembly 6 moves about its axis of rotation A1, and the lateral protrusion 690 of the insulating cover slides along the groove 220. The insulating cover 67 is thus forced to move relative to the support structure 63 by rotating about its hinge axis.

[0105] However, according to other embodiments of the invention (not shown), the insulating cover 67 may be arranged such that it can be moved by inertia or by actuation of a suitable elastic device coupled to the insulating cover 67 and the support structure 63.

[0106] Generally speaking, the insulating cover 67 can be in the first shielding position ( Figure 3 ) and the second shielding position ( Figure 5 ) move between (relative to support structure 63).

[0107] When it is in the first shielding position, the insulating cover 67 is not inserted between the electrical contacts of the switch pole.

[0108] When it is in the second shielding position, the insulating cover 67 has a shielding portion 68 that is inserted between the main contacts 51, 61 of the switch pole, that is, between one or more first fixed contacts 51 of the fixed contact assembly and one or more first movable contacts 61 of the movable contact assembly.

[0109] Preferably, when the insulating cover 67 is in the second shielding position, the shielding portion 68 covers one or more first movable contacts 61 of the movable contact assembly, thereby isolating these electrical contacts from the corresponding fixed contacts 51 of the fixed contact assembly.

[0110] The arrangement of the movable insulating cover 67 provides relevant advantages.

[0111] When inserted between the main contacts 51 and 61 of the switching pole, the shielding portion 68 significantly reduces the likelihood of arcing at these electrical contacts during the switching pole's opening and closing operation. This allows for reduced erosion of the first movable contact of the movable contact assembly, thereby extending the operational life of these movable contacts.

[0112] During the switching operation, once the first movable contact 61 separates from the first fixed contact 51, i.e., when the movable contact assembly moves from the first intermediate position to the second intermediate position, the insulating cover 67 obviously reaches the second shielded position. This solution provides an additional advantage because the shielding portion 68 reduces the possibility of arcing to other conductive parts of the movable contact assembly, such as the flexible conductor that electrically connects the conductive contact 65 to the second terminal 8 of the switch electrode.

[0113] Figures 6 to 9 A switching electrode according to another embodiment of the present invention is shown. In Figures 7 to 9 The diagram shows the movable contact assembly 6 in different operating positions during the operation of the switching pole.

[0114] In many respects, this embodiment of the invention is similar to Figure 2 , Figures 2A to 2B , Figures 3 to 5 The embodiment is as follows. However, in this case, the movable contact assembly 6 includes an insulating partition 66, which is arranged such that the main contacts 51, 61 of the switching pole are isolated from the arc contacts 52, 62 of the switching pole.

[0115] Preferably, the insulating partition 66 is made of an electrically insulating material, such as a thermosetting or thermoplastic material.

[0116] The insulating partition 66 protrudes toward the fixed contact assembly 5 and is at least partially slidably inserted into the receiving cavity 27 defined by the insulating housing 2.

[0117] As may be noted from the accompanying drawings, the insulating partition 66 is always inserted between one or more first fixed contacts 51 and one or more second fixed contacts 52 of the fixed contact assembly, and is also inserted between one or more first movable contacts 61 and one or more second movable contacts 62 of the movable contact assembly.

[0118] The insulating partition 66 thus prevents hot gases from diffusing into the lower region of the internal volume of the switching electrode, thereby greatly facilitating their flow into the arc-extinguishing region 4. This helps to confine the hot gases within the arc-extinguishing region 4 and makes the arc-extinguishing performance of the arc chamber 40 more efficient.

[0119] Since the insulating partition 66 permanently isolates the main contacts 51 and 61 of the switching pole from the arc contacts 52 and 62 of the switching pole, the possibility of re-breakdown of the main contacts 51 and 61 of the switching pole is significantly reduced.

[0120] In addition, the insulating partition 66 effectively prevents the electric arc from "jumping" to the conductive parts of the switching electrode outside the arc extinguishing area 4.

[0121] according to Figures 6 to 9 In the embodiment shown, the insulating partition 66 is fixed to the support structure 63 such that during the operation of the switching pole, the insulating partition 66 moves together with the support structure 63 about the rotation axis A1.

[0122] An insulating partition 66 is positioned in a first gap region between one or more first movable contacts 61 and one or more second movable contacts 62 of the movable contact assembly, and protrudes toward the fixed contact assembly 5.

[0123] The insulating partition 66 has a free end 661 that is in a relative position to the movable contacts 61, 62 of the movable contact assembly. During operation of the switching poles, as the movable contact assembly moves about the rotation axis A1, the free end 661 is inserted into the receiving cavity 27 and slides along the receiving cavity 27.

[0124] Preferably, the receiving cavity 27 is defined at the rear wall 24 of the insulating housing, in the area where the fixed contact assembly 5 is arranged.

[0125] Preferably, the receiving cavity 27 has an opening 270 for the passage of the insulating partition 66, the opening being located at a second spacing region, the second spacing region being located between one or more first fixed contacts 51 and one or more second fixed contacts 52 of the fixed contact assembly. Figure 9 ).

[0126] Preferably, in the area where the fixed contact assembly 5 is arranged, the rear wall 24 of the insulating housing has a through hole and a hollow protrusion 271 defining a receiving cavity 27, into which the insulating partition 66 is slidably inserted. Despite the presence of the insulating partition, this solution allows for a reduction in the lateral dimensions of the switching poles.

[0127] according to Figures 6 to 9 In the embodiment shown, the insulating partition 66 has a straight free end 661 that is inserted into and slides along the receiving cavity 27, which is a blind cavity.

[0128] The insulating partition 66 and the receiving cavity 27 have curved (i.e. arc-shaped) complementary profiles along a reference plane perpendicular to the axis of rotation A1.

[0129] However, according to other embodiments of the present invention (not shown), the heat insulation partition 66 and the receiving cavity 27 can be connected with... Figures 6 to 9 The solutions shown are arranged differently.

[0130] For example, the insulating partition 66 and the receiving cavity 27 can have different shaped profiles. As another example, the receiving cavity 27 can have additional holes configured to allow the receiving cavity to be in hydrodynamic communication with the internal volume of the switching electrode and / or the external environment.

[0131] Figures 10 to 12 A switch electrode according to another embodiment of the invention is shown. In these figures, the movable contact assembly 6 is shown in different operating positions during operation of the switch electrode.

[0132] In many respects, this embodiment of the invention is similar to Figures 6 to 9 The embodiment is as follows. However, in this case, the insulating partition 66 has a piston portion 661, which is always positioned in the receiving cavity 27 during the operation of the switching pole as the movable contact assembly 6 moves about the rotation axis A1, and the piston portion 661 slides along the receiving cavity 27.

[0133] The piston portion 661 is arranged such that during the opening and closing operation of the switching pole, a pressurized airflow blows toward one or more second fixed contacts 52 of the fixed contact assembly and one or more second movable contacts 62 of the movable contact assembly. Figures 11 to 12 --dotted line).

[0134] At the level of the arc contacts 52 and 62, the injection of pressurized air into the contact region 3 facilitates the flow of hot gas to the arc extinguishing region 4 and exerts a significant cooling effect on the arc contacts of the switching poles.

[0135] Preferably, the insulating partition 66 has an L-shaped free end 661 positioned relative to the movable contacts 61, 62 of the movable contact assembly. Conveniently, this shaped portion of the insulating partition 66 forms the aforementioned piston portion of the insulating buffer member.

[0136] Preferably, the cross-section of the receiving cavity 27 is designed such that its geometry is complementary and closely matches the shape of the piston portion 661. This helps to increase the air pressure blown toward the arc contacts 52, 62 of the switching poles.

[0137] According to the present invention, the switching electrode allows the proposed goals and objectives to be achieved.

[0138] The movable contact assembly of the switch pole is provided with a movable insulating cover 67 having a shielding portion 68, which can be inserted between the main contacts 51 and 61 of the switch pole during the opening and closing operation of the switch pole.

[0139] This solution can significantly reduce the likelihood of arcing between the main contacts of the switching poles, which greatly helps to protect these electrical contacts from excessive corrosion and thus extend their service life.

[0140] The movable insulating cover 67 also helps to reduce the possibility of arcing to other conductive parts of the movable contact assembly.

[0141] According to some embodiments of the invention, the movable contact assembly 6 includes an insulating partition 66 that is always inserted between the main contacts 51, 61 and the arc contacts 52, 62 of the switching pole, especially during the switching pole opening and closing operation.

[0142] The arrangement of the insulating partition 66 significantly reduces the possibility of an electric arc breaking down from the fixed second arc contact 52 to other conductive parts of the switching electrode (which are located outside the arc extinguishing region 4).

[0143] During the opening and closing operation of the switchgear, the insulating partition 66 of the movable contact assembly allows the arc generated between the electrical contacts in the separated state to be effectively confined within the arc-extinguishing region of the switching pole.

[0144] This is highly beneficial for the uniform distribution of the arc along the arc chamber 40 of the switching electrode, which makes their arc extinguishing performance more effective.

[0145] According to some embodiments, an insulating partition 66 is arranged such that, during the opening and closing of the switching electrode, pressurized air flows toward the arcing contacts 52, 62 of the switching electrode in the disconnected state. This solution allows for effective cooling of the arcing contacts 52, 62 of the switching electrode and further improves the isolation of the arc in the arc-extinguishing region 4 of the switching electrode.

[0146] The switching electrode of the present invention has a relatively simple and compact structure, is relatively easy to manufacture at an industrial level, and is cost-competitive compared to currently available solutions on the market.

Claims

1. A switching electrode (1) for a switching device (100), comprising: An insulating housing (2) defines the internal space of the switch electrode; The first terminal (7) and the second terminal (8) are capable of coupling with the corresponding line conductor of the power line; Fixed contact assembly (5), the fixed contact assembly includes a plurality of fixed electrical contacts (51, 52) electrically connected to the first terminal (7), the fixed electrical contacts including one or more first fixed contacts (51) and one or more second fixed contacts (52) spaced apart from and electrically insulated from the first fixed contacts. A movable contact assembly (6) includes a support structure (63) and a plurality of movable electrical contacts (61, 62) mounted on the support structure and electrically connected to the second terminal (8). The movable electrical contacts include one or more first movable contacts (61) and one or more second movable contacts (62). The movable contact assembly is reversibly movable about a rotation axis (A1) such that during operation of the switch pole, when the movable contact assembly (6) moves about the rotation axis (A1), the first movable contact (61) can be coupled to or disengaged from the first fixed contact (51), and the second movable contact (62) can be coupled to or disengaged from the second fixed contact (52). The movable contact assembly (6) is characterized in that it includes an insulating cover (67) that at least partially covers one or more conductive portions (65) of the movable contact assembly, the insulating cover moving together with the support structure about the axis of rotation (A1) of the movable contact assembly during operation of the switch pole, and moving relative to the support structure.

2. The switching electrode according to claim 1, characterized in that, The insulating cover (67) is reversibly movable between a first shielding position and a second shielding position. In the first shielding position, the insulating cover is not inserted between the electrical contacts (51, 52, 61, 62) of the switch pole. In the second shielding position, the insulating cover (67) has a shielding portion (68) inserted between one or more first fixed contacts (51) of the fixed contact assembly and one or more first movable contacts (61) of the movable contact assembly.

3. The switching electrode according to claim 2, characterized in that, The insulating cover (67) moves from the first shielding position to the second shielding position during the switching operation of the switch pole.

4. The switching electrode according to claim 3, characterized in that, When the shielding portion is in the second shielding position, the shielding portion (68) of the insulating cover (67) covers the one or more first movable contacts (61) of the movable contact assembly.

5. The switching electrode according to claim 4, characterized in that, The insulating cover (67) reaches the second shielding position during the opening and closing operation of the switch pole, before the second movable contact (62) separates from the second fixed contact (52).

6. The switching electrode according to any one of claims 2 to 5, characterized in that, The insulating cover (67) is hinged to the support structure (62) at a hinge axis parallel to the rotation axis (A1) of the movable contact assembly.

7. The switching electrode according to any one of the preceding claims, characterized in that, The movable contact assembly (6) includes an insulating partition (66) that protrudes toward the fixed contact assembly (5) and is at least partially slidably inserted into a receiving cavity (27) of the insulating housing. The insulating partition is inserted between one or more first fixed contacts (51) and one or more second fixed contacts (52) of the fixed contact assembly, and is also inserted between one or more first movable contacts (61) and one or more second movable contacts (62) of the movable contact assembly.

8. The switching electrode according to claim 7, characterized in that, The insulating partition (66) is positioned in a first gap region between one or more first movable contacts (61) and one or more second movable contacts (62) of the movable contact assembly.

9. The switching electrode according to any one of claims 7 to 8, characterized in that, The receiving cavity (27) has an opening (270) for the passage of the partition (66), the opening being located in a second interval region between the one or more first fixed contacts (51) and the one or more second fixed contacts (52) of the fixed contact assembly.

10. The switching electrode according to any one of claims 7 to 9, characterized in that, The insulating partition (66) has a free end (661) in a relative position to the movable contacts (61, 62) of the movable contact assembly, during operation of the switch pole, when the movable contact assembly (6) moves about the rotation axis (A1), the free end of the insulating partition is inserted into the receiving cavity (27) and slides along the receiving cavity.

11. The switching electrode according to any one of claims 7 to 10, characterized in that, The insulating partition (66) has a piston portion (661) that slides along the receiving cavity (27) during operation of the switch as the movable contact assembly (6) moves about the rotation axis (A1), and the piston portion (611) causes a pressurized airflow to blow toward the one or more second fixed contacts (52) of the fixed contact assembly and the one or more second movable contacts (62) of the movable contact assembly.

12. The switching electrode according to claims 10 and 11, characterized in that, The piston portion (661) is formed from the free end of the insulating partition (66).

13. A low-voltage switchgear, characterized in that, The low-voltage switchgear includes at least one switch pole (1) according to any one of the preceding claims.

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