Patent Description:
Further aspects relate to a method of manufacturing a circuit breaker having a nozzle.

Circuit breakers are known. Circuit breakers may have two contact elements which may move relative to each other along a central axis of the circuit breaker. An arc may form when the circuit breaker is opened, that is when the two contact elements are separated from each other. There may be an arcing zone between the two contact elements in which the arc is generated when the circuit breaker is opened or switched. The arc may be extinguished using an extinguishing gas.

<FIG> shows a cross-sectional representation of a part of a circuit-breaker. This circuit-breaker has two opposing contact elements <NUM>, <NUM> which are movable relative to each other along a central axis CA of the circuit-breaker by means of a drive. Contact element <NUM> is a metal contact tulip, contact element <NUM> is a metal contact pin. An arc area <NUM> is provided between the two contact elements <NUM>, <NUM>, in which, for example, an arc is formed when the circuit-breaker is opened, in which the two contact elements are separated from each other. Furthermore, the circuit-breaker shown in <FIG> has a cylindrical auxiliary nozzle 100b which at least partially encloses the contact element <NUM>. The inner jacket of the auxiliary nozzle faces the arc area <NUM>. Furthermore, the circuit breaker shown has a main nozzle 100a which at least partially encloses the auxiliary nozzle 100b. A channel <NUM> is formed between the auxiliary nozzle 100b and the main nozzle 100a, which connects the arc area <NUM> with a gas reservoir <NUM>, an upstream reservoir where the gas is temporarily stored with high pressure. The gas reservoir <NUM> is arranged circumferentially outside the auxiliary nozzle 100b. After the zero crossing of the current at which the current is meant to be interrupted during the switching operations of such a circuit-breaker, arc restrikes can occur due to the rise of the transient recovery voltage across the breaker terminals. These restrikes can run at least partially through channel <NUM> between the auxiliary nozzle 100b and the main nozzle 100a in an undesirable manner. Such an arc is indicated by the reference number <NUM> in <FIG>. It extends from the contact element <NUM> along the inner jacket of the main nozzle 100a to the end region of the main nozzle 100a forming a side wall of the channel <NUM> and then continues in the channel region at its upper boundary wall in <FIG> until it is finally deflected in the direction of the contact element <NUM>.

<CIT> describes an auxiliary nozzle which at least partially encloses one of the contact elements, a main nozzle which at least partially encloses the auxiliary nozzle, and a channel between the auxiliary nozzle and the main nozzle. During separation of contact elements when a circuit breaker is opened, a breakdown of insulating gas may initiate in the region around a contact element such as a plug tip. The breakdown of insulating gas may lead to a formation of a highly conductive plasma channel or a leader. The leader may have a tendency to stick to a nearby wall such as a nozzle surface. The leader may travel towards the other contact element such as a tulip under the drive of the electric field generated by the recovery voltage. Once the leader gets in proximity of the gap or gas channel between the main nozzle and the auxiliary nozzle, the leader may either bridge over the gap or gas channel and reach the tulip or remain attached to the surface of the nozzle, enter the gap and travel along a surface of the gas channel. The leader may travel until it is discharged on a metal part having the same potential as the other contact element or tulip.

Flashover traces may form when the latter situation, wherein the leader does not bridge the gap but enters the gap, occurs during a breaking operation. The flashover traces may form on the nozzle surfaces. Punctures or holes through the nozzle body may also form.

While performing a breaking sequence in a certification test, it is expected that the breaker fails to interrupt the current at the confirmation of minimum arcing time. The IEC standard prescribes that such failed breaking operations must not result in flashover traces. If flashover traces are revealed during an inspection of the breaker, the certification test might be considered to be failed even though the breaker has cleared the IEC sequence.

Thus, flashover in the gas channel that separates the auxiliary nozzle and main nozzle should be avoided. That is, propagation of a leader along a surface of the gas channel or gap between the auxiliary nozzle and main nozzle should be avoided.

<CIT> describes a configuration to guide a plasma channel or a leader from one contact element to the other contact element, along the inner jacket of the main nozzle and the auxiliary nozzle, such that the leader does not enter the gas channel or gap between the main nozzle and the auxiliary nozzle. <CIT> describes a configuration where one of the auxiliary nozzle or the main nozzle has an extension section bridging the channel in a direction parallel to the central axis such that the inner casing or inner jacket or inner surface of the auxiliary nozzle and the inner casing of the main nozzle adjoin one another in a direction parallel to the central axis of the nozzle without interruption or substantially without interruption. "Substantially without interruption" may include a configuration where a narrow gap between the auxiliary nozzle and the main nozzle, for example, a gap of less than <NUM>, is formed such that a leader travelling from one contact element to the other contact element bridges the gap and does not propagate through this gap into the channel. Openings or fluid ducts in the extension region connect the arc region to the gas reservoir and allow gas, such as extinguishing gas, to flow between them.

<CIT> describes that the auxiliary nozzle and the main nozzle are manufactured independently of each other. The openings or fluid ducts on the auxiliary nozzle or the main nozzle are selected such that the openings may be easily machined into the extension section during manufacture. The main nozzle and the auxiliary nozzle are then assembled.

The manufacture of a main nozzle and an auxiliary nozzle, and their assembly involve production tolerances and/or clearance between the auxiliary nozzle and the main nozzle. The tolerance and/or clearance between the auxiliary nozzle and the main nozzle plays a role in preventing an arc formed from propagating through the gap into the channel. The tolerance and/or clearance must not be so large as to impair the prevention of arc propagation into the channel between the auxiliary nozzle and the main nozzle. The tolerance and/or clearance between the auxiliary nozzle and the main nozzle also plays a role in the correct assembly of the circuit breaker. The clearance must not be so small as to cause difficulties during assembly of the auxiliary nozzle and the main nozzle.

Furthermore there is also a complication of mechanical coupling between the auxiliary nozzle and the main nozzle. A threaded connection between the auxiliary nozzle and main nozzle would encapsulate air and undermine dielectric recovery.

Additionally, the openings or fluid ducts on the extension sections on the auxiliary nozzle or the main nozzle connecting the arcing zone to the gas channel are selected with considerations of the associated machining and/or manufacturing process. Thus, the design and/or other processing of the openings such as finishing and/or material considerations may impose some requirements or limitations. That is, manufacturing and/or machining considerations may mean that the openings may not be completely optimized with respect to the performance of the nozzle or circuit breaker such as the gas flow between the gas reservoir and the arcing zone.

<CIT> describes an electrical switching device comprising a longitudinal axis, a contact arrangement with a first contact and a second contact, an insulating element enclosing at least partly the first contact, and a first auxiliary insulating element enclosing at least partly the second contact.

<CIT> describes a gas circuit breaker including a counter arc contact and a movable arc contact between both tips of which an arc is generated, as a counter contact part is separated from a movable contact part.

Thus, there is a need to improve the design and/or production method of the nozzles as well as a need to improve the mechanical stability of the nozzles while maintaining the prevention of leader propagation into the gas channel between the auxiliary nozzle and the main nozzle.

According to an aspect, there is provided a circuit breaker comprising a nozzle, having at least two contact elements and a gas reservoir, wherein the nozzle is manufactured by 3D printing as a single piece and configured to surround the at least two contact elements of the circuit breaker at least partially, the nozzle having an arcing zone formed along a central axis of the nozzle; and a gas channel formed within the nozzle and configured to fluidly connect the gas reservoir to the arcing zone, wherein at least one of the contact elements is configured to be movable.

An advantage is that the issues of manufacturing tolerances and mechanical coupling associated with having two separate nozzles may be eliminated. A nozzle made of a single piece obtained with 3D printing manufacturing may replace the combination of two nozzle parts such as an auxiliary nozzle and a main nozzle or an auxiliary nozzle and an insulating nozzle. Another advantage may be that flashovers in a channel or gas channel or propagation of a leader into a channel or gas channel may as effectively be avoided or prevented as, or be avoided or prevented better than a combination of two nozzle parts such as an auxiliary nozzle and a main nozzle, or an auxiliary nozzle and an insulating nozzle.

According to embodiments, the arcing zone is configured to be between two or more contact elements of the circuit breaker. Specifically, the arcing zone can be configured to be between the two or more contact elements of the circuit breaker when the nozzle is mounted in the circuit breaker.

According to embodiments, the gas channel is formed in a direction substantially parallel to the arcing zone.

According to embodiments, the nozzle further includes a plurality of fluid ducts formed within the nozzle and configured to fluidly connect the gas channel to the arcing zone.

An advantage may be that fluid ducts or openings may be designed or selected with 3D printing tools so as to optimise the flow of gas, such as extinguishing gas, or optimise for other circuit breaker performance considerations.

For example, an advantage is that the fluid ducts or openings on the nozzle may be designed or selected with 3D printing tools to optimise the performance of the nozzle such as improved gas flow between the gas channel and the arcing zone.

Additionally, 3D printing may provide improved freedom in the design and/or manufacture of the gas channel and/or fluid ducts.

According to embodiments, each fluid duct of the plurality of fluid ducts adjoins the gas channel at one end and adjoins the arcing zone at the other end.

According to embodiments, each fluid duct of the plurality of fluid ducts is formed in a direction substantially perpendicular to the central axis of the nozzle or in a direction at an angle to a radial axis, and wherein the radial axis is perpendicular to the central axis of the nozzle.

According to embodiments, each fluid duct of a plurality of fluid ducts is rotationally asymmetric about a radial axis, and wherein the radial axis is perpendicular to a central axis of the nozzle.

According to embodiments, the plurality of fluid ducts are distributed in a circumferential direction of the nozzle and/or the plurality of fluid ducts are arranged spatially with n-fold rotational symmetry about a central axis of the nozzle.

According to embodiments, the plurality of fluid ducts span an entire gas channel length or a part of a gas channel length.

The nozzle further includes a continuity of nozzle material configured to direct the propagation of a leader from a first contact element of the circuit breaker to a second contact element of the circuit breaker along at least a first surface of the nozzle, wherein the leader is highly conductive plasma.

An advantage may be that flashovers in a channel or gas channel or propagation of a leader into a channel or gas channel may be avoided or prevented.

According to embodiments, the first surface continuously abuts the arcing zone and/or the first surface is a surface of a throat of the nozzle.

According to embodiments, the first surface spans the nozzle.

According to embodiments, the nozzle is of a material composition, for example, including PTFE (polytetrafluoroethylene), FEP (fluorinated ethylene propylene), PFA (perfluoroalkoxy alkane), TFM (modified PTFE), MOS2 (molybdenum disulfide), BN (boron nitride), combinations thereof, or any fillings of one of these materials with another one.

According to another aspect, there is provided a circuit breaker having a nozzle.

Another aspect is directed to a method of manufacturing a circuit breaker having a nozzle, the circuit breaker having at least two contact elements, a gas reservoir, and a continuity of nozzle material configured to direct the propagation of a leader from the first contact element to the second contact element along at least a first surface of the nozzle, wherein the leader is highly conductive plasma, the nozzle is manufactured by 3D printing as a single piece and configured to surround the at least two contact elements of the circuit breaker at least partially, the nozzle having an arcing zone formed along a central axis of the nozzle; and a gas channel formed within the nozzle and configured to fluidly connect the gas reservoir to the arcing zone, wherein at least one of the contact elements is configured to be movable.

Further advantages, features, aspects and details that can be combined with embodiments described herein are evident from the dependent claims, the description and the drawings.

The details will be described in the following with reference to the figures, wherein:.

Reference will now be made in detail to the various embodiments, one or more examples of which are illustrated in each figure. Each example is provided by way of explanation and is not meant as a limitation. For example, features illustrated or described as part of one embodiment can be used on or in conjunction with any other embodiment to yield yet a further embodiment. It is intended that the present disclosure includes such modifications and variations.

Within the following description of the drawings, the same reference numbers refer to the same or to similar components. Generally, only the differences with respect to the individual embodiments are described. Unless specified otherwise, the description of a part or aspect in one embodiment applies to a corresponding part or aspect in another embodiment as well.

The reference numbers used in the figures are merely for illustration. The aspects described herein are not limited to any particular embodiment. Instead, any aspect described herein can be combined with any other aspect(s) or embodiment(s) described herein unless specified otherwise.

According to aspects or embodiments described herein, the problem of flashover traces in a channel or gas channel <NUM> in the nozzle <NUM> may be avoided. The problem of flashover traces may occur in case of an unsuccessful breaking operation. The breaking operation may be with a failure of dielectric type.

<FIG> show cross-sectional views of a nozzle <NUM> for a circuit breaker <NUM> according to embodiments described herein. <FIG> are cross-sectional views at two different angles about the central axis CA of the nozzle <NUM>, parallel to the central axis CA of the nozzle <NUM>.

As shown in <FIG>, the nozzle <NUM> is configured for a circuit breaker <NUM> having at least two contact elements <NUM>, <NUM>. At least one of the contact elements <NUM>, <NUM> is configured to be movable.

The nozzle <NUM> is manufactured as a single piece. The nozzle <NUM> is manufactured by 3D printing. The nozzle <NUM> is configured to surround the at least two contact elements <NUM>, <NUM> of the circuit breaker <NUM> at least partially. An arcing zone is formed along a central axis CA of the nozzle <NUM>. A gas channel <NUM> is formed within the nozzle <NUM>. The gas channel <NUM> is configured to fluidly connect the gas reservoir <NUM> to the arcing zone <NUM>.

The nozzle <NUM> is made of a single piece by 3D printing manufacturing. A single piece nozzle may replace two or more nozzle parts such as an auxiliary nozzle and a main nozzle. As shown in <FIG>, a single piece nozzle <NUM>, a continuity of nozzle material directs the propagation of a leader <NUM> from a first contact element <NUM> to a second contact element <NUM>. The leader <NUM> is highly conductive plasma. The continuity of material may be of an insulating material.

The leader <NUM> travels along a first surface <NUM> of the continuity of nozzle material. The first surface <NUM> may be continuously abutting the arcing zone <NUM>. The first surface <NUM> may be a surface of a throat of the nozzle <NUM>. The first surface <NUM> may span the nozzle <NUM>.

The throat of the nozzle <NUM> may be section or portion of the nozzle <NUM> with the smallest cross-section or diameter. The throat of the nozzle <NUM> may have a constant cross-section or changing cross-section. The throat of the nozzle <NUM> may be a section or portion of the nozzle <NUM> surround the arcing zone <NUM>. The throat of the nozzle <NUM> may be an inner surface of the nozzle <NUM>. The throat of the nozzle <NUM> may be a section or portion of the nozzle <NUM> adjoining the arcing zone <NUM>.

The leader <NUM> may travel until it discharges on a contact element <NUM>. For example, the contact element <NUM> may be a tulip contact or pin contact configured for circuit breakers <NUM>. The leader <NUM> may travel from the first contact element <NUM> to the second contact element <NUM>, vice versa, or between any two contact elements. Further, the contact element <NUM> may be the other one of the tulip contact or pin contact.

A nozzle <NUM> formed or manufactured as a single piece may have improved mechanical stability. A single piece nozzle <NUM> obtained with 3D printing may have improved mechanical stability. <FIG> shows a cross-sectional view of a nozzle <NUM>, where a plurality of fluid ducts <NUM> or openings <NUM> are formed. The plurality of fluid ducts <NUM> may be formed within the nozzle <NUM>. The plurality of fluid ducts <NUM> may be configured to ensure gas flow is not hindered. Gas may flow between the gas reservoir <NUM> and the arcing zone <NUM> through at least one or more fluid duct <NUM> or opening <NUM>. Alternatively or in addition, gas may flow between and/or the plurality of fluid ducts <NUM> may fluidly connect the gas channel <NUM> and the arcing zone <NUM>. The gas reservoir <NUM> may be a reservoir or chamber containing gas for extinguishing or quenching an arc. The gas in the gas reservoir <NUM> may be at a pressure higher than the gas elsewhere in the circuit breaker <NUM>.

The plurality of fluid ducts <NUM> or openings <NUM> may be delimited by parts of the same insulating material that the nozzle <NUM> is made of. The continuity of material may be provided to make it easier for the leader <NUM> of plasma to discharge on a contact element <NUM> instead of travelling upstream in a channel or gas channel <NUM>.

Possible complications arising from the mechanical coupling between two distinct or separate nozzles with extension sections or insulating bridges between said two distinct or separate nozzles, such as in <CIT>, may be avoided by the nozzle <NUM> of the present disclosure.

According to embodiments described herein, the nozzle <NUM> is configured for a circuit breaker <NUM> that has two opposing contact elements <NUM>, <NUM> movable relative to one another along a central axis CA of the circuit breaker <NUM>. One or more contact element <NUM>, <NUM> may be configured to be movable. Contact elements may be a metal contact tulip <NUM> or a metal contact pin <NUM>.

According to embodiments described herein, an arcing zone <NUM> is provided. An arcing zone <NUM> may be formed between the two or more contact elements <NUM>, <NUM>. The arcing zone <NUM> may be formed along a central axis CA of the nozzle <NUM>. The arcing zone <NUM> may be a zone where an arc is formed when the circuit breaker <NUM> is opened or when two contact elements <NUM>; <NUM> are separated from each other.

The nozzle <NUM> may be cylindrical or have any other suitable shape. The nozzle <NUM> may be formed of an insulating material. The nozzle <NUM> may be formed of a material composition suitable for use in circuit breakers. In particular, the material composition may be a result of the 3D printing. The material composition of the nozzle <NUM> may include, without being limited thereto, PTFE (polytetrafluoroethylene), FEP (fluorinated ethylene propylene), PFA (perfluoroalkoxy alkane), TFM (modified PTFE), MOS2 (molybdenum disulfide), BN (boron nitride), or any combination of at least two of these materials. For example, in one combination, one of these materials can be used as a matrix and another one can be used as a filler.

At least a part of the inner surface of the nozzle <NUM> may face, adjoin, delimit and/or abut the arcing zone <NUM>.

According to aspects described herein, a channel or gas channel <NUM> may be provided. The channel <NUM> may be configured for gas flow. That is, the channel may be a gas channel <NUM>. The gas channel <NUM> may be formed in a direction substantially parallel to the arcing zone <NUM>. Alternatively or in addition, the gas channel <NUM> may be formed in a direction at an angle to a direction that is parallel to the arcing zone <NUM>.

Additionally or alternatively, the gas channel <NUM> may be formed as a delimited channel, that is not spanning the entire circumference of the nozzle <NUM> or the gas channel <NUM> may be formed spanning substantially the entire circumference of the nozzle <NUM>. A plurality of gas channels <NUM> may be provided instead of or in addition to an annular gas channel <NUM>.

The gas channel <NUM> may extend parallel or substantially parallel to the central axis CA of the nozzle <NUM>. The gas channel <NUM> may be configured to fluidly connect the gas reservoir <NUM> to the arcing zone <NUM>. The gas channel <NUM> may be configured to fluidly connect the gas reservoir <NUM> to the plurality of fluid ducts <NUM>. For example, the plurality of gas channels <NUM> may resemble a plurality of fluid ducts <NUM>, e.g. in that the plurality of channels <NUM> connect to the plurality of fluid ducts <NUM>.

In particular, the plurality of fluid ducts <NUM> may be formed in the nozzle <NUM>. According to embodiments described herein, the fluid ducts <NUM> can be openings in the nozzle material. The plurality of fluid ducts <NUM> may be configured to fluidly connect the gas reservoir <NUM> to the arcing zone <NUM>. Additionally or alternatively, the plurality of fluid ducts <NUM> may be configured to fluidly connect the gas channel <NUM> to the arcing zone <NUM>. Additionally or alternatively, the plurality of fluid ducts <NUM> may be configured to adjoin the gas channel <NUM> at one end and adjoin the arcing zone <NUM> at the other end.

The plurality of fluid ducts <NUM> may be configured to allow the flow of gas such as extinguishing gas or insulating gas, in particular between the arcing zone <NUM> and the gas channel <NUM> and/or gas reservoir <NUM>. The plurality of fluid ducts <NUM> may be configured to optimise the flow of gas, such as extinguishing gas or insulating gas between the arcing zone <NUM>, and the gas channel <NUM> or gas reservoir <NUM>. Alternatively, instead of an extinguishing gas, it may be a vacuum, or partial vacuum state.

The plurality of fluid ducts <NUM> may adjoin the arcing zone <NUM> and/or the gas channel <NUM>. The plurality of fluid ducts <NUM> may extend at right angles or substantially at right angles to the central axis CA of the nozzle <NUM>. Alternatively or in addition, the plurality of fluid ducts <NUM>, or the axis of the plurality of fluid ducts <NUM> may be at an angle to a radial axis of the nozzle <NUM>. The radial axis may be perpendicular to the central axis CA of the nozzle <NUM>. That is, at least one fluid duct <NUM> may be tilted with respect to the radial axis. The radial axis of the nozzle <NUM> is perpendicular to the central axis CA of the nozzle <NUM>.

The plurality of fluid ducts <NUM> may be rotationally asymmetric about the radial axis. For example, the plurality of fluid ducts <NUM> may have an oval or a rectangular or a rounded rectangular cross-section or any other suitable cross-section. Alternatively, the plurality of fluid ducts <NUM> may be rotationally symmetric about a radial axis. For example, the plurality of fluid ducts <NUM> may have a circular cross-section, without being limited thereto. In particular, the plurality of fluid ducts <NUM> can have any cross-section. Further, the fluid ducts <NUM> may have different geometries or shapes or cross-sections from each other. In addition or alternatively, the fluid ducts may have changing cross-section along their length or axis.

The plurality of fluid ducts <NUM> may be spatially arranged or distributed in a circumferential direction or rotational direction about the central axis CA of the nozzle <NUM>. Additionally or alternatively, the plurality of fluid ducts <NUM> may be spatially arranged or distributed in the axial direction or in a direction parallel to the central axis CA of the nozzle <NUM>. Alternatively or in addition, the plurality of fluid ducts <NUM> may be arranged spatially or distributed with n-fold rotational symmetry about the central axis CA of the nozzle <NUM>. Alternatively or in addition, the plurality of fluid ducts <NUM> may span the entire gas channel <NUM> length or a part of the gas channel <NUM> length.

A continuity of nozzle material in the nozzle <NUM> may be configured to guide, direct or conduct the propagation of a leader <NUM>, which may be highly conductive plasma. The continuity of nozzle material may be configured to direct a leader <NUM> from the first contact element <NUM> of the circuit breaker <NUM> to the second contact element <NUM> of the circuit breaker <NUM>.

In particular, the continuity of nozzle material may guide a leader <NUM> along a first surface <NUM> of the nozzle <NUM>. The first surface <NUM> of the nozzle <NUM> may continuously adjoin or abut the arcing zone <NUM>. Alternatively or in addition, the first surface <NUM> may be a surface of a throat of the nozzle <NUM>. Alternatively or in addition, the first surface <NUM> may span the nozzle. Alternatively or in addition, the first surface <NUM> may span from a first axial position to a second axial position. The first axial position may correspond to the axial position of the first contact element <NUM> and/or the second axial position may correspond to the axial position of the second contact element <NUM>. The axial position may be a position in the direction parallel to the central axis CA of the nozzle <NUM>.

The continuity of material or the first surface <NUM> may prevent, hinder or discourage a leader <NUM> or an arc from travelling, propagating or spreading into the gas channel <NUM> and/or the plurality of fluid ducts <NUM>. In particular, the first surface <NUM> may provide or be formed by a continuity of material or insulating material or insulating surface to guide, direct or conduct a leader <NUM> to propagate from one contact element <NUM> to another contact element <NUM>.

According to the invention a method of manufacturing a circuit breaker <NUM> having a nozzle <NUM> is provided. The method includes 3D printing a nozzle <NUM> for a circuit breaker <NUM>. The circuit breaker <NUM> has at least two contact elements <NUM>, <NUM>. The circuit breaker <NUM> has a gas reservoir <NUM>. The nozzle <NUM> is manufactured or formed as a single piece.

The nozzle <NUM> is configured to surround the at least two contact elements <NUM>, <NUM> of the circuit breaker <NUM> at least partially. The nozzle <NUM> comprises an arcing zone <NUM> formed along a central axis CA of the nozzle <NUM>. The nozzle <NUM> comprises a gas channel <NUM> formed within the nozzle <NUM>. The nozzle <NUM> comprises a gas channel configured to fluidly connect the gas reservoir <NUM> to the arcing zone <NUM>. At least one of the contact elements <NUM>, <NUM> is configured to be movable.

Claim 1:
Circuit breaker (<NUM>) comprising a nozzle (<NUM>), at least two contact elements (<NUM>; <NUM>), a gas reservoir (<NUM>) and a continuity of nozzle material configured to direct the propagation of a leader (<NUM>) from the first contact element (<NUM>) to the second contact element (<NUM>) along at least a first surface (<NUM>) of the nozzle (<NUM>), wherein
the leader (<NUM>) is highly conductive plasma,
the nozzle is manufactured by 3D printing as a single piece and configured to surround the at least two contact elements (<NUM>; <NUM>) of the circuit breaker (<NUM>) at least partially,
at least one of the contact elements (<NUM>; <NUM>) is configured to be movable and
the nozzle (<NUM>) comprising an arcing zone (<NUM>) formed along a central axis (CA) of the nozzle (<NUM>) and a gas channel (<NUM>) formed within the nozzle (<NUM>) and configured to fluidly connect the gas reservoir (<NUM>) to the arcing zone (<NUM>).