circuit breaker

Description

[0001] The invention relates to a circuit breaker. The circuit breaker serves in particular to protect a line or a specific device. The circuit breaker, for example, functions as a disconnect switch and is preferably a component of a power switch.

[0002] Circuit breakers typically feature an electrical switching system. This system is usually mechanically designed, allowing for galvanic isolation. In this case, the electrical switching system usually includes a contact and a corresponding mating contact that is movably mounted. Specifically, the contact and mating contact are each connected to a busbar, with the mounting typically provided by the busbars themselves. When the circuit breaker is closed, meaning current can flow through it, the contact rests on the mating contact, establishing a direct mechanical connection between them. An electric current then flows through the contact and mating contact.

[0003] When the circuit breaker is closed, the busbars are in a closed position. Moving the busbars into this closed position is usually accomplished by a hand lever, which is mechanically coupled to the busbar. The hand lever itself typically has two positions: one corresponding to the closed position of the busbars and the other to the open position.

[0004] When the circuit breaker trips, the two busbars are separated and thus moved into the open position. This prevents current flow. The separation process should occur relatively quickly, which is why at least one of the busbars is usually spring-loaded, with the spring acting in the direction of the open position. It is also necessary for the hand lever to move to the other position so that the tripping is noticeable to the user. Furthermore, this allows the busbars to be returned to the closed position. However, if the overload condition persists, for example, if the fault has not been rectified, the busbars must be returned to the open position almost immediately.Since the hand lever is usually blocked by the user, a so-called free release mechanism is provided, allowing the busbars to be moved into the open position even if the hand lever is blocked. This partially decouples the hand lever from the busbars, meaning the busbars can only be moved in one direction relative to each other using the hand lever: from the open to the closed position.

[0005] In the event of an overload, if a relatively high electric current occurs, an arc may form between the contact and the mating contact, leading to the erosion of the contact and / or mating contact. This can result in partial melting of the contact and / or mating contact. If the mating contact is then brought into contact with the contact in a short period of time, the contact and mating contact will fuse together, as their surfaces are partially liquefied. After cooling, it is no longer possible to separate them solely due to the spring force. Therefore, the circuit breaker can no longer be used, as tripping—the intended interruption of the electric current flow—is no longer possible due to the fusion of the contact and mating contact.

[0006] DE 103 29 392 A1 discloses a main circuit breaker comprising a switching mechanism with a rotatable double-contact striking element. This can be tripped via a thermal, a magnetic or a mechanical actuation.

[0007] A spring mechanism is provided for closing the contact after short-circuit shutdown, with a coil with a plunger armature serving for magnetic actuation and a bimetallic arrangement for thermal actuation.

[0008] In DE 60 2004 005723 T2, a switching device is shown. This comprises a housing, two fixed contacts which are supported by the housing, a movable contact which is selectively applied to the fixed contacts, an equipment mechanism including an actuating element for selectively moving the movable contact to the fixed contacts, and a releasing device for selectively disconnecting the movable contact from the fixed contacts.

[0009] The invention is based on the objective of providing a particularly suitable protective switch, advantageously increasing reliability and / or service life.

[0010] According to the invention, this problem is solved by the features of claim 1. Advantageous further developments and embodiments are the subject of the dependent claims.

[0011] The circuit breaker is used to conduct and interrupt an electric current. It is suitable, specifically designed and configured for this purpose. Furthermore, the circuit breaker is suitably mechanically designed. Preferably, the rated current conducted by the circuit breaker is between 1 A and 125 A, expediently between 1 A and 30 A, between 30 A and 60 A, or between 60 A and 100 A. The circuit breaker is suitable, specifically designed and configured, to conduct an alternating current, which in particular has an electrical voltage between 100 V and 800 V, and for example, between 277 V, 480 V, or 600 V. Alternatively, the circuit breaker is suitable, specifically designed and configured, to conduct a direct current, in which case the electrical voltage is in particular between 100 V and 1,500 V. The circuit breaker is preferably used in an industrial plant, particularly in industrial automation.Alternatively, the circuit breaker is a component of a building installation.

[0012] The circuit breaker serves primarily to protect a device, such as an electric motor, or an electrical line. For this purpose, the circuit breaker monitors the electrical voltage and / or current for overload conditions and interrupts the flow of electricity if at least one of the values ​​exceeds a certain limit and / or if a change in the respective value within a certain period of time exceeds another limit.

[0013] The circuit breaker has a busbar that is movably mounted between a closed and an open position. The busbar can be in either the closed or the open position. In other words, the busbar can be in the closed position and subsequently in the open position, and vice versa. The two positions are distinct: in the closed position, an electric current flows through the busbar during operation. In other words, current can flow through the busbar in the closed position. However, in the open position, no electric current can flow through the busbar during operation. Specifically, in the open position, the busbar is separated from other components of the circuit breaker that are at electrical potential.Preferably, the busbar is galvanically isolated from the other components.

[0014] The busbar, when in operation and in the closed state, carries an electric current. Therefore, the busbar is at least partially made of a metal, preferably copper, i.e., pure copper or a copper alloy. This results in a comparatively low ohmic resistance. For example, the busbar may be coated with a plating consisting of nickel, tin, or silver. Consequently, chemical reactions between the other components of the busbar, especially the copper, are prevented or at least slowed down. This also makes it possible to attach other components to the busbar, for example, by soldering or welding.

[0015] In the open position of the busbar, the circuit breaker is in a non-conductive state, meaning no electrical current flows through it. In other words, any device protected by the circuit breaker cannot be energized. In the closed position of the busbar, the circuit breaker is in a conductive state, and therefore any device protected by the circuit breaker will receive current.

[0016] The circuit breaker also includes a tripping device. This tripping device triggers a response in the event of an overload, i.e., if the electrical current or voltage flowing through the circuit breaker meets the conditions for an overload. In particular, the tripping device is at least partially mechanical, ensuring a mechanical response when an overload occurs.

[0017] Furthermore, the circuit breaker has a hand lever that can be moved between a first position and a second position, and back again. In other words, it is possible to move the hand lever to the first position or the second position. The hand lever allows for manual operation of the circuit breaker. In other words, the hand lever is used by a user to operate the circuit breaker. The first position corresponds to the electrically non-conductive state of the circuit breaker, i.e., an open state. Consequently, the first position corresponds to the open position of the busbar. The second position of the hand lever corresponds to the electrically conductive state of the circuit breaker and thus to the closed position of the busbar.

[0018] The circuit breaker further comprises a mechanism by which the busbar, the tripping device, and the hand lever are coupled. Consequently, it is possible to actuate the busbar using the hand lever. It is also possible to actuate the busbar using the tripping device. The coupling is such that when the hand lever is moved from the first position to the second position, the busbar is moved from the open position to the closed position. Thus, the circuit breaker is put into the electrically conductive state by actuating the hand lever. In the electrically non-conductive state, the hand lever is in the first position and the busbar is in the open position. Preferably, the hand lever and / or the busbar are held in the second position or the closed position, in particular by means of a locking mechanism in the mechanism and / or the tripping device.The locking mechanism is released, in particular, when the release device is triggered.

[0019] Furthermore, the coupling is such that when the release device is triggered, the busbar is moved from the closed position to the open position. In other words, when the release device is triggered, the busbar, if in the closed position, is moved to the open position. If the busbar is already in the open position, it remains there when the release device is triggered. Additionally, when the release device is triggered, the hand lever is moved from the second position to the first position, provided it is not blocked. However, if the hand lever is blocked in the second position, for example, due to manual operation, the busbar is still moved from the closed position to the open position when the release device is triggered, and the hand lever remains in the second position.Once the blockage is released, it is advisable to then move the hand lever to the first position.

[0020] In summary, the busbar is moved independently of the hand lever position and always when the tripping device is triggered. Because the busbar moves from the closed to the open position when the tripping device is triggered, the electrical current flow through the circuit breaker is interrupted, which increases safety and is consistent with the circuit breaker's operating principle. If the hand lever is moved to the first position, the user can see that the circuit breaker is in its non-conductive state. In this case, it is also possible to move the hand lever from the first to the second position to move the busbar from the open to the closed position again.However, if the hand lever is blocked in the second position, for example due to user intervention, the electrical current flow is interrupted regardless of the hand lever's position when the busbar moves to the open position, thus increasing safety. In summary, the circuit breaker also functions as a free-running trip.

[0021] Furthermore, the mechanical coupling is such that when the hand lever is moved from the second position to the first position, the busbar is moved from the closed to the open position. For example, any locking mechanism is released in this case. Thus, by operating the hand lever, it is also possible to switch the circuit breaker from the electrically conductive state to the electrically non-conductive state. The movement of the busbar from the closed to the open position occurs regardless of whether the busbar is blocked in the closed position. In other words, the busbar moves from the closed to the open position if it is essentially free to move. However, if the busbar is blocked in the closed position, it will still move to the open position when the hand lever is moved.In other words, the hand lever exerts a force on the bus bar, causing it to open. Consequently, it is possible to manually apply a force to the bus bar via the hand lever, with the force exerted depending on the force applied to the hand lever.

[0022] If the busbar is blocked in the closed position, the hand lever is also held in the second position, or at least in an intermediate position. When the hand lever is moved (manually) to the first position, the force acting on the hand lever is redirected by the mechanism to the busbar, thus transferring the force to it. In other words, the hand lever releases the blockage of the busbar. Therefore, if the busbar is blocked in the closed position, and if the busbar remains in the closed position even after the release device is triggered, it is possible to move the busbar back to the open position using the hand lever.

[0023] Such a blockage occurs, for example, due to a partial melting of the busbar with other components of the circuit breaker, particularly if a comparatively severe overload has preceded it, leading to partial liquefaction of the busbar. The design of the mechanism breaks up this melting. Consequently, any electrical current still flowing through the circuit breaker is interrupted by actuating the hand lever, thus increasing safety. The circuit breaker is then ready for use again, especially if the electrical current flow was terminated by another protective mechanism, such as a further overcurrent protection device, particularly a fuse. Therefore, the mechanism allows the circuit breaker to continue to be used even after a comparatively severe overload, thus extending its service life.Consequently, it is not necessary to replace the circuit breaker, thus reducing operating costs. Furthermore, the mechanical design allows verification of the busbar's closed position by operating the hand lever, increasing reliability.

[0024] The circuit breaker advantageously comprises a housing that accommodates the mechanism, the busbar, the tripping device, and at least part of the hand lever. In particular, the hand lever is mounted within the housing. The housing is advantageously made of an electrically non-conductive material, preferably plastic. The housing provides electrical insulation, thus preventing personal injury. It also prevents or significantly reduces the ingress of dirt particles into the interior of the circuit breaker, which could interfere with the functioning of the mechanism.

[0025] The hand lever is advantageously made of an electrically non-conductive material, preferably plastic. This ensures that even in the event of a malfunction of the circuit breaker, injury to a person, especially the user, is prevented if they touch the hand lever.

[0026] The circuit breaker, for example, functions as a disconnect switch. A suitable term for a circuit breaker is a contact system with a tripping unit and signaling and / or indication of the switching state, where the signaling / indication specifically describes the disconnecting function. Here, the switching state is expediently indicated by positive guidance. The tripping unit is preferably an overcurrent release or at least includes one. In summary, the circuit breaker functions as a disconnect switch. The circuit breaker is preferably a component of a power circuit breaker, which, for example, includes a fail-safe element, such as a fuse, that is electrically connected in series with the circuit breaker. Thus, a power circuit breaker with a disconnecting function and a fuse is provided.

[0027] The mechanism features a slide that is mounted to be laterally displaceable. In other words, the slide is mounted to be transversely displaceable along the transverse direction. This allows the slide to be moved laterally, with the displacement limited, for example, by two stops or at least by one stop. The slide is connected to the busbar. Thus, when the slide moves, the busbar is moved between the open and closed positions. For example, the slide is connected to the busbar by means of a hinge, which pivots the busbar between the open and closed positions by means of the slide. Preferably, however, the busbar is rigidly attached to the slide, so that the busbar is also mounted to be laterally displaceable by means of the slide. Consequently, stress and the risk of breakage are reduced.

[0028] For example, an additional component is mechanically arranged between the slider and the busbar. Preferably, however, the slider is attached directly to the busbar. As a result, the number of required components is reduced and robustness is increased. The slider is, for example, designed to be electrically non-conductive and preferably made of a plastic, particularly by injection molding. Thus, no electrical current is conducted through the slider, and it exhibits essentially no electrical potential during operation, which essentially eliminates the need for further insulation. The slider allows the busbar to be moved between the open and closed positions without any further contact with the busbar. This increases safety.

[0029] Preferably, the slide is spring-loaded. In other words, the circuit breaker includes a spring that acts on the slide, for example, directly or indirectly via another component. The spring is advantageously supported against another component of the circuit breaker, particularly its housing. Preferably, the spring is compressed when the busbar is moved from the open to the closed position. Thus, the spring force acts on the slide and consequently on the busbars, compressing the slide in such a way that the busbar is moved into the open position. Advantageously, the circuit breaker includes a locking mechanism by which the slide or another component of the mechanism connected to the slide is locked when the busbar is in the closed position.Advantageously, the locking mechanism is actuated by the release device, so that the locking mechanism is released when the release device is triggered. Consequently, the spring moves the busbar from the closed position to the open position when the release device is triggered. The spring is, for example, a coil spring, which reduces manufacturing costs. Alternatively, the spring can be, for example, a torsion spring, leaf spring, disc spring, or (compression) air spring. In summary, the slide is spring-loaded by the spring in such a way that when the release device is triggered, the busbar moves from the closed position to the open position.

[0030] The hand lever is rotatably mounted around a pivot axis, thus reducing its space requirements. When moved from the first to the second position, the hand lever pivots / rotates around this axis. The mechanism includes a torsion spring that springs the hand lever into the first position. In other words, the torsion spring is tensioned when the hand lever is moved to the second position. For this purpose, the torsion spring is advantageously supported eccentrically on the hand lever and also fixedly on the other side, preferably on the housing of the circuit breaker. Advantageously, a locking mechanism is provided so that the hand lever is held in the second position against the spring force. If the locking mechanism is released, particularly due to the activation of the tripping device or manual operation of the hand lever, the hand lever moves from the second to the first position.However, if the lever is blocked in the second position and held with a force greater than the spring force, the hand lever will remain in the second position. If the blockage is subsequently released, the lever will preferentially move to the first position due to the torsion spring, regardless of whether the release mechanism is triggered.

[0031] The mechanism comprises a first coupling element that is rotatably mounted on the hand lever eccentrically to the axis of rotation. The first coupling element can be rotated relative to the hand lever, and when the hand lever rotates about the axis of rotation, the first coupling element, or at least its point of attachment to the hand lever, also moves about the axis of rotation. Preferably, the axis of the rotatable mounting of the first coupling element on the hand lever is parallel to the axis of rotation. Advantageously, one end of the coupling element is rotatably connected to the hand lever, thus reducing the space required.

[0032] The first coupling element is guided in a first guide of the slide. The guide is, in particular, a recess in the slide, wherein preferably the first coupling element engages in the first guide, advantageously one end of the first coupling element. It is possible to move the first coupling element within the first guide relative to the slide. However, removing the first coupling element from the first guide is not possible. For example, it is not possible to move the first coupling element away from the first guide in at least one or two directions, whereas, for example, inserting the first coupling element into the first guide perpendicular to the transverse direction, for example parallel to the axis of rotation, is possible without hindrance. Thus, assembly is simplified.

[0033] The first cam track includes a section extending in the transverse direction. This allows the slide to be moved transversely independently of the hand lever. Thus, it is possible to move the conductor rail from the open to the closed position, and consequently the slide, particularly by means of other mechanical components, even if the hand lever is locked in the second position. However, especially when the conductor rail is locked in the closed position, and when the hand lever is moved from the second to the first position, the first coupling element is moved against a limit of the first cam track in the transverse direction. Therefore, with further movement of the hand lever via the first coupling element, the force acting on the hand lever is transferred to the slide.Due to the first coupling element, it is therefore possible to exert force on the busbar so that it is moved from the closed position to the open position, whereby the first cam, in particular due to the section running in the transverse direction, ensures that other functions of the circuit breaker are not impaired.

[0034] The first coupling element is, for example, designed as a single piece and is particularly U-shaped or formed by means of a straight component. Preferably, both ends engage with the hand lever or the first cam. This allows for a comparatively simple design of the first coupling element, which reduces manufacturing costs. Alternatively, the first coupling element is, for example, curved or comprises several components, preferably deflectors. This allows the force acting on the slide when the hand lever is actuated to be adjusted. In particular, a lever arm is utilized, so that the force exerted by the hand lever is comparatively large. The maximum distance along which the force must act is comparatively short, since only the blockage of the conductor rail in the closed position needs to be released.

[0035] Advantageously, the first coupling element is made of a relatively robust material, preferably a metal, such as steel. This increases its robustness. Preferably, the slider is made of plastic, so that the electrical potential of the first coupling element is independent of the electrical potential of the busbar. The first coupling element is preferably made of steel wire and preferably manufactured in the form of a clamp.

[0036] The mechanism comprises a second coupling element rotatably mounted on the hand lever eccentrically to the axis of rotation, the axis of which is preferably parallel to the axis of rotation. For example, the distance of the second coupling element to the axis of rotation is less than or equal to the distance of the first coupling element to the axis of rotation. However, it is particularly preferred that the distance of the second coupling element to the axis of rotation is greater than that of the first coupling element. Thus, the second coupling element travels a greater distance when the hand lever is moved. The second coupling element is guided in a second cam of a rocker arm of the mechanism. The second cam is, for example, straight or curved. The rocker arm itself is rotatably mounted on the slide, particularly at its end, with the axis preferably parallel to the axis of rotation. The second cam is offset from the bearing point of the rocker arm on the slide.Thus, when the hand lever is rotated around its axis, the second coupling element is moved within the second cam until it reaches a stop in the second cam. Following this, the rocker arm is rotated relative to the slide.

[0037] The second coupling element is, for example, a straight section or U-shaped, and thus formed in particular by means of a clamp. Preferably, one end is attached to the hand lever, while the other end rests in the second recess. Due to the U-shaped design, the second coupling element can be mounted relatively easily by inserting it into the corresponding receptacles parallel to the axis of rotation. Alternatively, the second coupling element is, for example, curved and thus comprises at least one arc or several arcs. Preferably, the second coupling element is made of a metal, preferably steel, for example, a steel wire. This increases its robustness.

[0038] Advantageously, the mechanism includes a first locking lever that is rotatably mounted, preferably on the housing and / or advantageously about an axis parallel to the axis of rotation. The first locking lever is actuated by the release device. In other words, the mechanism is coupled to the release device by means of the first locking lever. Preferably, the locking lever rotates when the release device is triggered. In particular, the first locking lever is spring-loaded so that, after rotation due to the triggering of the release device, it is returned to its original position. The first locking lever has a support point that is arranged eccentrically to the rotatable mounting. Thus, when the first locking lever rotates, the support point is also rotated. The support point is provided for the rocker arm and is spaced apart from the second cam.

[0039] The support point serves to limit the pivoting movement (rotation) of the rocker arm relative to the slide. In other words, when the hand lever is moved and the second coupling element in the second cam is moved to its stop, the rocker arm is initially rotated relative to the slide until it rests against the support point. Specifically, the rocker arm rests on the support point at its end, i.e., at the end opposite the slide. With further rotation, this movement causes the rocker arm to pivot around the support point, thus moving the slide laterally. This movement, in particular, moves the busbar into the closed position.When the conductor rail is in the closed position, the second coupling element is arranged essentially in a transverse direction, so that the slide is held in a precarious equilibrium in this position against any spring acting on it. Therefore, when the first locking lever is moved by the release device, this precarious equilibrium is broken, and the slide is moved transversely by the spring. However, if no significant disturbance occurs, the slide is locked in place by the second coupling element, which is also arranged essentially in a transverse direction. In a variation, the second coupling element is arranged slightly obliquely relative to the transverse direction, but further movement of the second coupling element is hindered by the second cam, which is, in particular, slightly curved.

[0040] If, with the hand lever blocked, the first locking lever is partially rotated by the release mechanism, the rocker arm is no longer held by the locking lever, but is only rotatable relative to the slide. Due to the prevailing weight force, the rocker arm is pivoted relative to the slide in this case, which leads to a change in the position of the second coupling element. Therefore, the unstable equilibrium is also disrupted. This again allows movement of the slide in the lateral direction, so that the conductor rail is moved into the open position. In summary, the support point and the second cam decouple the hand lever from the conductor rail.

[0041] For example, the busbar is arranged along the transverse direction and is thus adjusted when the slider is moved in the transverse direction. This provides a comparatively compact circuit breaker. However, it is particularly preferred that the busbar is arranged along a longitudinal direction perpendicular to the transverse direction. This simplifies the electrical contacting of the busbar. In this configuration, the busbar is also advantageously mounted so that it can be moved longitudinally by means of the slider, meaning that the busbar can only be moved in the transverse direction. Consequently, its robustness is increased.

[0042] Preferably, the circuit breaker has a second busbar arranged along its longitudinal axis. The two busbars are thus arranged parallel to each other, advantageously overlapping along a certain section. In the closed position, the busbar is mechanically connected to the second busbar, for example directly, or indirectly via other components. At a minimum, however, the busbar is electrically connected to the second busbar in the closed position. In the open position, the busbar is mechanically separated from the second busbar. Thus, an electrical current flow from the busbar to the second busbar and vice versa is not possible. In other words, the two busbars are galvanically isolated from each other in the open position.

[0043] Preferably, one terminal of the circuit breaker is electrically contacted with the secondary busbar, so that an electrical potential is present on the secondary busbar during operation, or at least so that the secondary busbar is rigidly connected to other components of any circuit to be protected. This simplifies the design. The secondary busbar is advantageously made of the same material as the primary busbar, preferably copper, which may, for example, be coated. The secondary busbar is, for example, rigidly mounted, in particular rigidly connected to the housing, which simplifies the design. Alternatively, the secondary busbar is movably mounted and preferably spring-loaded. In this case, the springs act in the direction of the primary busbar, so that when the primary busbar is moved into the closed position, the secondary busbar is also moved against the spring force.Thus, in the closed position, the two busbars are in a force-fit connection, preventing them from unintentionally separating due to adverse conditions. This also improves electrical contact.

[0044] The additional busbar preferably carries a first contact and a second contact, spaced apart longitudinally. The spacing is advantageously greater than 4 mm, 5 mm, or 1 cm. For example, the spacing is less than 5 cm, 4 cm, or 3 cm. For instance, the spacing is essentially 2 cm, with a deviation of up to 10%, 5%, or 0%, respectively. Furthermore, the additional busbar has a first electrical connection. The first electrical connection serves to electrically connect the additional busbar to other components of the circuit breaker, such as any terminal. In particular, the first electrical connection is implemented by means of a terminal or the like. Alternatively, the first electrical connection is integrally formed with any other components, so that the additional busbar transitions into the other component at the first electrical connection.It is advantageous for the first power connection to form one end of the further power rail in the longitudinal direction.

[0045] The busbar carries a first and a second contact, spaced apart longitudinally. This spacing is advantageously greater than 4 mm, 5 mm, or 1 cm. For example, the spacing is less than 5 cm, 4 cm, or 3 cm. Preferably, the spacing is substantially equal to 2 cm, with a deviation of up to 10%, 5%, or 0%. Such a spacing allows for a comparatively compact circuit breaker.

[0046] Furthermore, the second busbar has a second electrical connection. Specifically, this second electrical connection forms the longitudinal boundary of the second busbar, i.e., one of its longitudinal ends. The second electrical connection serves to electrically connect the second busbar to other components of the circuit breaker. For example, the second electrical connection may be designed as a terminal. Alternatively, the busbar may transition into another component at the second electrical connection, so that the second busbar is integrally formed with this other component via the second electrical connection. Preferably, the other component is connected to the second electrical connection by means of a wire and expediently electrically contacted by it. This ensures that the electrical contact is maintained even if the busbar moves laterally.

[0047] The second busbar partially overlaps the first busbar along its length. The contacts and mating contacts are also located longitudinally between the two power connections in this overlap area. The first contact is paired with its first mating contact, and the second contact with its second mating contact. When the busbar is in the closed position, these contacts preferably make direct mechanical contact with each other. The contacts and mating contacts preferably serve to conduct the electric current.

[0048] Due to the longitudinal spacing of the contacts and mating contacts, a section of each busbar is formed between them, through which a portion of the electric current is carried in the electrically conductive state. In this case, the electric current is carried parallel to each other in the longitudinal direction of both busbars. Consequently, synchronized magnetic fields are formed, which is why a magnetic attraction force acts, at least partially, between the two busbars in this area. In particular, this force is essentially proportional to the product of the electric current carried by the contacts and mating contacts and the ratio of the distance between the contacts and mating contacts to the distance between the two busbars.

[0049] This magnetic force opposes the magnetic force that develops in the contact and mating contacts, which pushes the two busbars apart. Consequently, the resulting forces acting on the busbars with an increasing electric current are comparatively small. Therefore, the force required to keep the circuit breaker in the electrically conductive state, i.e., the busbar in the closed state, is comparatively low. This simplifies the mechanical design.

[0050] Preferably, at least one of the contacts, preferably all contacts, and / or one of the mating contacts, expediently all mating contacts, is made of a silver-based contact material. Preferably, silver nickel (AgNi), silver tin oxide (AgSnO2), silver tungsten (AgW), or silver graphite (AgC) is used as the silver-based contact material. In this way, a comparatively robust contact or mating contact is created.

[0051] Alternatively, the secondary busbar may have only a single contact, and the secondary busbars may have only a single mating contact, made, for example, of the same material, such as a silver alloy. In another alternative, the circuit breaker includes an additional busbar that is spaced apart from the secondary busbar and preferably arranged on a common straight line with it. In the electrically conductive state of the circuit breaker, the secondary busbar and the additional busbar are bridged by the secondary busbar, which is thus preferably in direct mechanical contact with both the secondary and the additional busbar. Consequently, current flow between the secondary and the additional busbar is possible via the secondary busbar. In the open state, however, the secondary busbar is spaced apart from both the secondary and the additional busbar.This results in a double interruption, which prevents the formation of arcs when the circuit breaker is switched, i.e., when the busbar is moved from the closed to the open position.

[0052] The tripping device is, for example, hydraulic, magnetic, or thermal. Alternatively, the tripping device comprises a combination of these. In this case, a magnetic field is generated depending on the electric current flowing through the circuit breaker, which triggers the tripping device. Alternatively, heating is used to trigger the tripping device. Particularly preferably, the tripping device comprises a bimetal / bimetallic element, such as a bimetallic strip or a bimetallic snap disc, and is formed, for example, by means of this. Here, the bimetal / bimetallic element / bimetallic strip / bimetallic snap disc is preferably rigidly clamped at its end, suitablely to the housing, if any. The opposite end is, for example, in direct mechanical contact with the mechanism, preferably with one of the locking levers, if any.During operation, the bimetal / bimetallic element / bimetallic strip / bimetallic snap disc is subjected to the electric current supplied by the circuit breaker. Excessive current can cause the bimetal / bimetallic element / bimetallic strip / bimetallic snap disc to heat up and consequently deform. This design provides a relatively robust tripping mechanism.

[0053] The invention further relates to a circuit breaker with such a protective switch. In particular, this provides galvanic isolation of current-carrying components if the busbar is in the open position. Advantageously, a fuse is electrically connected in series with the protective switch in the circuit breaker. This further increases safety.

[0054] Exemplary embodiments of the invention are explained in more detail below with reference to a drawing. The drawing shows: Fig. 1 a schematic diagram of an industrial plant with a circuit breaker, Figs. 2, 3 each a perspective view of a first embodiment of the circuit breaker, which has a hand lever and a busbar, Fig. 4 a side view of the circuit breaker in an open state, Fig. 5 according to Fig. 4 the circuit breaker in a closed state, as shown in Fig. 6 Fig. 4 the circuit breaker in the open position, with the hand lever blocked, as shown in Fig. 7 Fig. 4 the circuit breaker in the closed state, with a blocked busbar, Fig. 8; a second embodiment of the circuit breaker in perspective, Fig. 9; the circuit breaker in an open state in a side view, Fig. 10. Fig. 9 the circuit breaker in a closed state, as shown in Fig. 11 Fig. 9 the circuit breaker in the open position, with the hand lever blocked, as shown in Fig. 12 Fig. 9the circuit breaker in the closed state, with a blocked busbar, and Fig. 13 another embodiment of the busbar.

[0055] The in the Figures 8 to 12 The second embodiment shown does not fall within the scope of protection of claim 1.

[0056] Corresponding parts are marked with the same reference symbols in all figures.

[0057] In Figure 1 Figure 1 shows a schematic diagram of an industrial plant 2, which includes a power supply 4 and an actuator 6 operated by it. The power supply 4 provides an alternating current of 50 Hz or 60 Hz. The voltage is, in particular, 277 V or 480 V. The actuator 6 comprises, for example, an electric motor or a press and is electrically connected to the power supply 4 via a line 8, so that current is supplied to the actuator 6 via the line 8.

[0058] Furthermore, the industrial plant 2 includes a circuit breaker 10, which in one embodiment is part of the line 8 and is located in a control cabinet (not shown). Alternatively, the circuit breaker 10 is located at the power supply 4 or at the actuator 6. The circuit breaker 10 has a protective switch 12 and a fuse 14 connected in series with it. The protective switch 12 has a disconnecting function, and the electrical series connection is integrated into one of the conductors of the line 8.

[0059] In this example, the rated current of circuit breaker 10 is 60 A. If the rated current is exceeded by more than a certain limit, for example, 1.1 times the rated current, the electrical current flow is interrupted by circuit breaker 12. In other words, circuit breaker 12 trips and opens, thus becoming non-conductive. Fuse 14, which in this example is a glass tube fuse, does not trip in this case. It only trips at five times the rated current, i.e., at 300 A, and its tripping time is shorter than that of circuit breaker 12. Therefore, in this case, the electrical current flow is interrupted by fuse 14, while circuit breaker 12 remains in the conductive state.Due to this connection between the circuit breaker 12 and the fuse 14, the power switch 10 is essentially ready for use immediately by resetting the circuit breaker 12, even with a relatively small overcurrent exceeding the rated current. No component replacement is necessary, thus reducing operating costs. However, if the overcurrent is relatively large, especially if it exceeds 300 A, damage is possible when the mechanically equipped circuit breaker 12 is switched. In this case, an arc occurs, which can damage components of the circuit breaker 12. Since the circuit breaker 12 is not tripped, it is not damaged, and the power switch 10 is also ready for use again after the fuse 14 is replaced.

[0060] In the Figure 2 and 3Each of the following is a perspective view of a first embodiment of the circuit breaker 12. The circuit breaker 12 has a tripping device 16 which includes a bimetallic strip 18. The bimetallic strip 18 is strip-shaped and is rigidly connected at one end to a first terminal bar 20 and thus electrically contacted with it. This end is rigidly attached to a housing of the circuit breaker 12 (not shown in detail), the housing being made of an electrically non-conductive plastic. The first terminal bar 20 is made of an electrically conductive material, namely a copper alloy or pure copper, and is also strip-shaped, with one end attached to the bimetallic strip 18. The remaining end of the first terminal bar 20 forms one of the terminals of the circuit breaker 12, which is electrically contacted, in particular, with the fuse 14.In one version, this end of the first connecting rail 20 protrudes from the housing, which is not shown in detail.

[0061] The remaining end of the bimetallic strip 18 is freely movable relative to the housing of the circuit breaker 12 (not shown). This end rests eccentrically against a first locking lever 22 of a mechanism 24, which is rotatably mounted about a bearing axis 26 on the housing (not shown). Furthermore, the first locking lever 22 has a support point 28, also eccentrically arranged, located on the side opposite the bimetallic strip 18 relative to the bearing axis 36. The support point 28 is formed by a rod-shaped section of the first locking lever 22, which is made in one piece from a plastic material and runs parallel to the bearing axis 26. Consequently, when the bimetallic strip 18 is bent, the first locking lever 22 is partially rotated about the bearing axis 26, so that the support point 28 is also moved about the bearing axis 26. Thus, the first locking lever 22 is actuated by means of the release device 16.

[0062] An elastically deformable stranded wire 30 is attached to the freely movable end of the bimetallic strip 18, either by welding or soldering. The stranded wire 30 is thus electrically connected to the bimetallic strip 18. The remaining end of the stranded wire 30 is attached to a busbar 32 and electrically connected to it. The busbar 32 runs longitudinally 34 and is stamped from a copper sheet with a silver coating. The contact point of the stranded wire 38 with the busbar 32, which is furthest outwards in the longitudinal direction 34, forms a second electrical connection 35. At both ends of the busbar 32 in the longitudinal direction 34, there is a first mating contact 36 and a second mating contact 38. Thus, the two mating contacts 36 and 38 are spaced apart from each other in the longitudinal direction 34.The two opposing contacts 36, 38 are arranged on one side of the busbar 32 and are made of silver nickel and electrically contacted with the busbar 32.

[0063] The mating contacts 36, 38 point in a transverse direction 40, perpendicular to the longitudinal direction 34, towards a further busbar 42, which is arranged along the longitudinal direction 34. The first mating contact 36 is located in the transverse direction 40 above a first contact 44, and the second mating contact 38 is located in the transverse direction 40 above a second contact 46, each of which carries the further busbar 42 and points towards the busbar 32. Thus, the two contacts 44, 46 are also spaced apart from each other in the longitudinal direction 34. The two contacts 44, 46 are made of the same material as the mating contacts 36, 38, i.e., silver-nickel, and the further busbar 42 is stamped from a copper sheet and also coated with silver. The further busbar 42 runs perpendicular to the busbar 32 and perpendicular to the transverse direction 90.In contrast, the conductor rail 32 runs parallel to the longitudinal direction 34 and parallel to the transverse direction 40.

[0064] The second busbar 42 has a first power connection 48, with the contacts 44, 46 and the mating contacts 36, 38 located longitudinally 34 between the first power connection 48 and the second power connection 35 in an overlap area 50 of the busbar 32 with the second busbar 42. The first power connection 48 is located outside the overlap area 50. A second terminal 52 is connected to and electrically contacted at the first power connection 48. The second terminal 52 also projects from the housing of the circuit breaker 12 (not shown) and serves for connection to the line 8.

[0065] The circuit breaker 12 further comprises two springs 54, which are designed as helical springs and extend in the transverse direction 40. The springs 54 are arranged between a base of the housing (not shown) and the additional busbar 42 and are supported by it. The additional busbar 42 can be moved in the transverse direction 40 against the springs 54, thereby tensioning the springs 54.

[0066] The mechanism 24 further comprises a slide 56, which is mounted to be longitudinally displaceable in the transverse direction 40 and to which the conductor rail 32 is attached in the transverse direction 40 at one end. Thus, the conductor rail 32 is also mounted to be movable in the transverse direction 40. The slide 56 has a transverse extension 58 by means of which a spring (not shown) is guided and supported. The spring is further supported on a housing (not shown). The spring exerts a spring load on the slide 56, with the direction of movement in the transverse direction 40 being directed away from the further conductor rail 42.

[0067] The slide 56 has a first cam 60 in the form of an elongated slot extending in the transverse direction 40. The first cam 60 is thus formed by a section 62 extending in the transverse direction 40. A first coupling element 64, which is bent from a steel wire into a U-shaped clamp, is guided in the first cam 60, with one of its parallel legs arranged in the first cam 60. The leg extending transversely to this runs parallel to the transverse direction 40, and the other of the mutually parallel legs is rotatably mounted on a hand lever 66, one free end of which also projects from the housing. The hand lever 66 is rotatably mounted about a pivot axis 68. The connection of the first coupling element 64 is eccentric to the pivot axis 68 and thus spaced apart from it, with the rotatable mounting of the coupling element 64 being parallel to the pivot axis 68.In summary, the hand lever 66 is rotatable about the axis of rotation 68 and can therefore assume a first position 70, which is shown in the figures. In other words, the hand lever 66 can be moved into the first position 70. The hand lever 66 has a receptacle 72 within which a torsion spring (not shown) is arranged, by means of which the lever 66 is spring-loaded into the first position 70. In other words, when no other forces act on the hand lever 66, it is moved into the first position 70 by means of the torsion spring. When moving out of the first position 70, however, the torsion spring, which is arranged concentrically to the axis of rotation 68, is tensioned.

[0068] A second coupling element 74 is rotatably mounted on the hand lever 66, with its bearing axis parallel to the axis of rotation 68. The second coupling element 74 is U-shaped, designed as a clamp, and made of steel wire. One of its parallel legs is attached to the hand lever 66, with the distance to the axis of rotation 68 being greater than the distance of the first coupling element 64 to the axis of rotation 68. The remaining parallel leg of the second coupling element 74 is guided in a second cam 76 of a rocker arm 78, which is rotatably mounted on the slide 56. The connection point of the rocker arm 78 is located at the end of the slide 56 opposite the conductor rail 32 in the transverse direction 40. The second cam 76 is spaced apart from the connection point on the slide 56 and runs essentially in a straight line. Furthermore, the rocker arm 78 is rotatable about an axis that is parallel to the axis of rotation 68.

[0069] In Figure 4The circuit breaker 12 is shown in a partial side view. Here, the circuit breaker 12 is in a non-conductive state. In other words, the first terminal 20 and the second terminal 52 are galvanically isolated from each other. This is the case when the busbar 32 is in an open position 80, in which the busbar 32 is spaced apart from the other busbar 42 by means of the mechanism 24, so that the contacts 44, 46 and the mating contacts 36, 38 are not mechanically in contact with each other. In this case, the hand lever 66 is in the first position 70.

[0070] When the hand lever 66 is pivoted about the axis of rotation 68 into a second position 82, the second coupling element 74 is moved in the second cam 76 until it reaches the end of the second cam 76. With further force applied, the second coupling element 74 cannot be moved transversely with respect to the second cam 76, and the rocker arm 78 is pivoted relative to the slide 56 until its end rests against the support point 28 of the first locking lever 22. Until then, the slide 56 does not move laterally due to the spring supported on the extension 58. However, once the rocker arm 78 rests against the support point 28, it cannot be pivoted further, and the support point 28 forms a bearing point for the rocker arm 78, which is thus pivoted about the support point 28.As a result, the slider 56 is moved in the transverse direction 40 until the mating contacts 36, 38 mechanically contact the contacts 44, 46 supported by the other busbar 42. With further movement of the hand lever 66, the springs 54 are compressed so that the two busbars 32, 42 are in frictional contact with each other. The movement of the slider 56, and therefore also of the hand lever 66, continued until the second coupling element 74 is essentially moving in the transverse direction 40. Further movement of the hand lever 66 is then prevented by a stop (not shown), and the hand lever 66 is in the second position 82. Thus, the hand lever can be moved between the first and second positions 70, 82. In this case, the mechanism 24 is in an unstable equilibrium due to the spring acting on the extension 58, and the busbar 32 is in a closed position 84.

[0071] During the movement of the hand lever 66 from the first position 70 to the second position 82, the first coupling element 64 slides freely along the first cam 60. For clarity, the slide 56 is shown semi-transparently in the figures.

[0072] When the busbar 32 is in the closed position 84, an electric current can flow from the first busbar 20 via the bimetallic strip 18, the wire, the busbar 32, and the mating contacts 36, 38 via contacts 44, 46 to the next busbar 42 and from there to the second terminal 52. As a result, the circuit breaker 12 is in the electrically conductive state.

[0073] Due to the arrangement of the mating contacts 36, 38 and the contacts 44, 46, the direction of the electric current flow in the busbar 32 and the other busbar 42 is parallel to each other, at least in the overlap area 50, which is why a synchronized magnetic field is induced there. Because of the magnetic field induced in this way, the two busbars 32, 42 are pressed towards each other in the transverse direction 40, resulting in a comparatively reliable electrical contact. To reinforce this effect, the busbar 32 is bulged towards the other busbar 42 in the overlap area 50 between the two mating contacts 36, 38, whereby the two busbars 32, 42 do not directly touch each other in this area.

[0074] When the hand lever 66 is moved from the second position 82 to the first position 70, the sequence of movements is reversed, so that by actuating the hand lever 66 the busbar 32 is moved into the open position 80. This movement is assisted by the spring acting on the extension 58 and by the torsion spring.

[0075] If a relatively large electric current flows through the bimetallic strip 18, causing it to heat up, the freely movable end of the bimetallic strip 18 bends, causing the first locking lever 22 to rotate. As a result, the support point 28 is no longer held by the rocker arm 78. The rocker arm pivots further relative to the slide 56. In this case, the second cam 76 also pivots, thus moving the second coupling element 74. Consequently, the unstable equilibrium is lost, and the slide 56 is moved in the transverse direction 40 by means of the spring acting on the extension 58, so that the busbars 32 are separated from the other busbar 42. As a result, the contacts 44, 46 are separated from the mating contacts 36, 38, thus interrupting the current flow.Due to the mechanical coupling by means of the second coupling element 74, the hand lever 66 is also moved into the first position 70, so that the circuit breaker 12 is again in the position 70. Figure 4 the state shown, whereby the bimetallic strip 18, for example, is still bent. After cooling, however, it is again in the state shown. Figure 4 The position shown. Furthermore, the rotary movement of the hand lever 66 is supported by the torsion spring, which is not shown in detail.

[0076] However, if the hand lever 66 is blocked in the first position 70, and the bimetallic strip 18 is bent due to excessive current flow, the first locking lever 22 is moved again, so that the support point 28 no longer supports the rocker arm 78. This allows the rocker arm 78 to pivot further relative to the slide 56, whereby the second coupling element 74 moves in the second guide 76. Thus, the unstable equilibrium is lost, and the slide 56 can be moved in the transverse direction 40 by means of the spring acting on the extension 58, so that the busbar 32 is moved into the open position 80. Thus, in this case as well, the electrical current flow between the two connecting rails 20 and 52 is interrupted.

[0077] If the busbar 32 is blocked in the closed position 84, as in Figure 7As shown, if the rocker arm 78 is not in contact with the support point 28, for example due to a manual movement of the hand lever 66 from the second position 82 to the first position 70, or if the release device 16 has been triggered, movement of the hand lever 66 to the first position 70 is not possible. In this case, the first coupling element 64 in the first cam 64 is moved to its stop, and the system prevents further movement of the hand lever 66. When force is applied to the hand lever 66 in the direction of the first position 70, this force is transmitted to the slide 56 and consequently to the bus bar 32. Thus, it is possible to detach the bus bar 32 from the other bus bar 42 by manually actuating the hand lever 66 and to break any fusion of contacts 44, 46 with the mating contacts 36, 38.

[0078] In summary, the mechanism 24 couples the busbar 32, the release device 16, and the hand lever 66. When the hand lever 66 is moved from the first position 70 to the second position 82, the busbar 32 moves from the open position 80 to the closed position 84. When the release device 16 is triggered, the busbar 32 moves from the closed position 84 to the open position 80. In this case, the hand lever 66 moves from the second position 82 to the first position 70, provided the hand lever 66 is not blocked. Otherwise, at least the busbar 32 is moved accordingly. When the hand lever 66 moves from the second position 82 to the first position 70, the busbar 32 moves from the closed position 84 to the open position 80. This occurs regardless of whether the busbar 32 is blocked in the closed position 84.In this case, the blockage of the busbar 32 is lifted by means of the force manually applied to the hand lever 66.

[0079] In Figure 8 A second variant of the circuit breaker 12 is shown in perspective, in section, in which the two connecting rails 20, 52, the busbar 32 with the two mating contacts 36, 38, and the wires 30 remain unchanged. The other busbar 42, as well as the contacts 44, 46, and the springs 54, are also unchanged. Furthermore, the function and the arrangement of the individual components relative to each other are not altered. The slide 56 is again present, which has the first cam 60 with the section 62 extending in the transverse direction 40, in which the first coupling element 64 is guided. However, the first cam 60 also includes a further section 86, which extends in the longitudinal direction 34, as shown in the Figure 9-12The figures show the circuit breaker 12 in a side view. Thus, the first cam 60 is L-shaped. Here, the further section 86 is offset in the transverse direction 40 from the busbar 32 towards the hand lever 66 with respect to section 60.

[0080] The first coupling element 64 is eccentrically connected to the hand lever 66, which is rotatably mounted about the axis of rotation 68. The second coupling element 74 and the rocker arm 78 are omitted, and the mechanism 24 has a third coupling element 88, which is rotatably mounted on the first coupling element 64. The connection of the third coupling element 88 to its free end and to the first coupling element 64 is located between its two ends, i.e., in the transverse leg of the L-shaped first coupling element 64. The remaining end of the third coupling element 88 is guided in a third cam 90 of a second locking lever 92, which is rotatably mounted on the housing in the same manner as the first locking lever 22. In other words, the first locking lever 22 is replaced by the second locking lever 92. The second locking lever 92 is actuated by means of the bimetallic strip 18 of the release device 16.Provided that the release device 16 is not actuated, i.e. as long as the bimetallic strip 18 runs in the transverse direction 40, the third cam 19 is essentially aligned in the longitudinal direction 34.

[0081] If the hand lever 66 is in the first position 70, which is in Figure 9 As shown, the first coupling element 86 is located in the further section 86 of the first cam 60, and the conductor rails 32 are in the open position 80.

[0082] When the hand lever 66 is rotated into the second position 82, which is in Figure 10As shown, the first coupling element 64 is partially moved in the transverse direction 40 towards the further conductor rail 42. This movement acts via the first cam 60 on the slider 56, which is thus moved in the transverse direction 40 towards the further conductor rail 42. The arrangement of the first cam 60 with respect to the hand lever 66 and its direction of movement is such that the first coupling element 64 is not moved into the section 62 extending in the transverse direction 40 due to the direction of the acting force. When the first coupling element 64 is substantially arranged in the transverse direction 40, the contacts 44, 46 are in contact with the respective mating contacts 36, 38, and the conductor rail 32 is in the closed position 84, as shown in Figure 10 shown. Here too, an unstable equilibrium is achieved. In summary, in the closed position 84, the busbar 32 is mechanically in contact with the other busbar 42.

[0083] When the hand lever 66 is manually moved from the second position 82 to the first position 70, the opposite movement sequence is performed. If the release device 16 is triggered, i.e., if the free end of the bimetallic strip 18 is moved, the second locking lever 92 is moved, and consequently the third coupling element 88. This exerts a force on the first coupling element 64 in the longitudinal direction 34, thus disrupting the unstable equilibrium. Even a relatively small movement of the third coupling element 88 disrupts the unstable equilibrium, so that the first coupling element 64 remains in the further section 86. Due to the disruption of the equilibrium, the slide 56 is moved away from the further conductor rail 42 into the open position 80 by the spring (not shown) in the transverse direction 40, which is in Figure 9As shown, in the open position 80, the conductor rail 32 is mechanically separated from the other conductor rail 42. The spring force acting on the slide 56 also acts via the first coupling element 64 on the hand lever 66, which thus rotates into the first position 70. The rotational movement is further assisted by the torsion spring.

[0084] If the hand lever 66 is blocked in the second position 82, as in Figure 11shown, and if the release device 16 is triggered, i.e., the free end of the bimetallic strip 18 is moved, the first coupling element 64 is moved further into the section 62 of the first cam 62 extending in the transverse direction 40 by means of the third coupling element 88. As a result, a movement of the slide 56 in the transverse direction away from the further conductor rail 42 is possible. Therefore, the slide 56 is moved in the transverse direction 40 by means of the spring, and the conductor rail 32 is spaced away from the further conductor rail 42 and thus brought into the open position 80.

[0085] If the busbar 32 is held in the closed position 84 due to the contacts 44, 46 welding to the mating contacts 36, 38, and is thus blocked, the first coupling element 64 remains engaged in the first cam 60, specifically at the stop of the first cam 60 in the transverse direction 40 that is furthest from the other busbar 42. When the hand lever 66 is rotated, the first coupling element 64 is partially moved away from the other busbar 42 in the transverse direction 40, so that a force directed away from the other busbar 42 is exerted on the slide 56. Consequently, any fusion is broken, and the busbar 32 is moved from the closed position 84 to the open position 80 if the busbar 32 is blocked in the closed position 84. In this case, the blockage is released by the application of force.

[0086] In Figure 13A further modification of the circuit breaker 12 is shown schematically in a simplified form. Again, the slider 56 and the busbar 32 connected to it are shown, with the first mating contact 36 and the second mating contact 38 spaced apart from each other in the longitudinal direction 34. The additional busbar 42 is also present, carrying the first contact 44, which is identical in construction to the previous embodiments. However, the additional busbar 42 is offset in the longitudinal direction 34, so that the overlap area 50 is reduced. Furthermore, an additional busbar 94 is present, carrying the second contact 46. The additional busbar 42 and the additional busbar 94 are galvanically isolated from each other, and the stranded wire 30 is soldered to the additional busbar 94, which in turn is electrically contacted with the bimetallic strip 18. In the open position 80, which is shown in Figure 13As shown, the mating contacts 36, 38 are spaced apart from the contacts 44, 46. When the closed position 84 is assumed, the first mating contact 36 is brought against the first contact 44 and the second mating contact 38 against the second contact 46, so that the further busbar 42 and the additional busbar 94 are bridged by means of the busbar 32. Thus, current can be carried out in this case. The modification of the further busbar 42 and the use of the additional busbar 94 are carried out in variants not shown in detail with the in Figure 2 bis Figure 12 illustrated embodiments of the circuit breaker 12.

[0087] The invention is not limited to the embodiments described above. Rather, other variants of the invention can also be derived by a person skilled in the art without departing from the subject matter of the invention. In particular, all individual features described in connection with the individual embodiments can also be combined with one another in other ways without departing from the subject matter of the invention. Reference symbol list

[0088] 2 Industrial plant 4 Power supply 6 Actuator 8 Cable 10 Circuit breaker 12 Protective switch 14 Fuse 16 Trip device 18 Bimetallic strip 20 First connection rail 22 First locking lever 24 Mechanism 26 Bearing axis 28 Support point 30 Stranded wire 32 Busbar 34 Longitudinal direction 35 Second power connection 36 First opposite contact 38 Second opposite contact 40 Transverse direction 42 Second busbar 44 First contact 46 Second contact 48 First power connection 50 Overlap area 52 Second connection rail 54 Spring 56 Slider 58 Extension 60 First cam 62 Section 64 First coupling element 66 Hand lever 68 Rotary axis 70 First position 72 Receptacle 74 Second coupling element 76 Second cam 78 Toggle lever 80 Open position 82 Second position 84 Closed position 86 Further section 88 Third coupling element 90 Third cam 92 Second locking lever 94 Additional busbar

Claims

1. Circuit breaker (12), in particular of a power breaker (10), having a busbar (32) which is movably mounted between a closed position (84) and an open position (80), having a tripping device (16), having a hand lever (66) which can be moved between a first position (70) and a second position (82), and having a mechanism (24) by means of which the busbar (32), the tripping device (16) and the hand lever (66) are coupled in such a way - that, when the hand lever (66) is moved from the first position (70) to the second position (82), the busbar (32) is moved from the open position (80) to the closed position (84), - that, when the tripping device (16) is tripped, the busbar (32) is moved from the closed position (84) to the open position (80) and the hand lever (66) is moved from the second position (82) to the first position (70) if it is not blocked, and - that, when the hand lever (66) is moved from the second position (82) to the first position (70), the busbar (32) is moved from the closed position (84) to the open position (80), wherein the blocking of the busbar (32) is lifted by means of the hand lever (66) if the busbar (32) is blocked in the closed position (84), so that the busbar (32) is moved regardless of whether the busbar (32) is blocked in the closed position (84), characterized in that the mechanism (24) has a slide (56) which is displaceably mounted in a transverse direction (40) and is connected to the busbar (32), wherein the hand lever (66) is rotatably mounted about a rotation axis (68), wherein a first coupling element (64) is rotatably mounted on the hand lever (66) eccentrically in relation to the rotation axis (68) and is guided in a first slotted guide (60) of the slide (56), which slotted guide has a portion (62) running in the transverse direction (40), and wherein a second coupling element (74) is rotatably mounted on the hand lever (66) eccentrically in relation to the rotation axis (68) and is guided in a second slotted guide (76) of a rocker arm (78), which is rotatably mounted on the slide (56).

2. Circuit breaker (12) according to Claim 1, characterized in that the slide (56) is spring-loaded.

3. Circuit breaker (12) according to Claim 1 or 2, characterized in that the mechanism (24) has a torsion spring, by means of which the hand lever (66) is spring-loaded to the first position (70).

4. Circuit breaker (12) according to any of Claims 1 to 3, characterized in that the mechanism (24) has a rotatably mounted first locking lever (22), which is actuated by means of the tripping device (16), wherein the first locking lever (22) has an eccentrically arranged support point (28) for the rocker arm (78).

5. Circuit breaker (12) according to any of Claims 1 to 4, characterized in that the busbar (32) is arranged along a longitudinal direction (34), which is perpendicular to the transverse direction (40).

6. Circuit breaker (12) according to Claim 5, characterized by a further busbar (42), which is arranged along the longitudinal direction (34), wherein the busbar (32) mechanically bears against the further busbar (42) in the closed position (84), and wherein the busbar (32) is mechanically separated from the further busbar (34) in the open position (80).

7. Circuit breaker (12) according to Claim 6, characterized in that the further busbar (42) supports a first contact (44) and a second contact (46), which is spaced apart from the first contact in the longitudinal direction (34), and has a first current connection (48), and in that the busbar (32) supports a first mating contact (36) and a second mating contact (38), which is spaced apart from the first mating contact in the longitudinal direction (34), and has a second current connection (35), wherein the busbar (32) partially overlaps the further busbar (42) along the longitudinal direction (34), and wherein the contacts (44, 46) and the mating contacts (36, 38) between the two current connections (35, 48) are arranged in the overlap region (50) in the longitudinal direction (34).

8. Circuit breaker (12) according to any of Claims 1 to 7, characterized in that the tripping device (16) has a bimetallic strip (18) .