Electrical safety device and electrical installation system

Abstract

The subject of the invention is an electrical fuse, which includes a body (1), two inlets for connecting wiring conductors and a heat-sensitive element (2) for conductive connection of wiring conductors depending on temperature. All inlets and the heat-sensitive element (2) are located in the body (1). The electrical fuse is characterized by the fact that the body (1) includes a carrier (3) with extinguishing agent.

Description

[0001] Electrical fuse and wiring system

[0002] Technical Field

[0003] The subject of the invention is an electrical fuse that interrupts an electrical circuit in the event of a fault, for example in a socket, and at the same time extinguishes possible fire in the electrical network.

[0004] Background of the Invention

[0005] At present, there are many variants of protective elements for electrical networks. A fault (e.g. loose wire in a terminal, material degradation, short circuit) often results in an increase in heat in an electrical circuit. The electrical circuit is protected against short circuit or overload by electrical fuses. In the event of a large, longer-lasting increase in heat, it is necessary to disconnect the circuit as soon as possible to avoid damage that can lead to a fire.

[0006] A widely used type of protective element is a residual current device, which compares the current that goes into the appliance and the current that goes from the appliance. In case of difference between these currents, the residual current device RCD breaks the circuit. In the event of a fault in which the temperature rises and there is a risk of fire, but there is no current leakage, the residual current device is ineffective. The residual current device protects the user from electric shock.

[0007] Another type of protective element are electrical fuses, which disconnect the electrical circuit in the event of a fault when the current limit value is exceeded. One of the types of fuses used are, for example, thermal fuses, which are published, for example, in document US7323966B2. The design is based on a fusible insert with a spring. When a certain limit temperature is reached, the spring is released, which separates the contacts with the wires and breaks the circuit. These temperature fuses are mainly used to protect electrical appliances. In the event of a large-scale fault, when a fire is already occurring, disconnecting the circuit alone is not enough to stop the dangerous situation. Fire extinguishing elements are installed to extinguish the fire in the electrical installation. The installation of these protective elements (fuses and fire extinguishing elements) and their connection is a demanding and complicated activity that requires a professional technician. These protective elements often involve complicated electronic devices that are difficult to connect and increase the overall cost of purchasing and installing the protective element. These devices are also more susceptible to damage. To install protective elements to sockets, it is also often necessary to dig a separate hole in the wall for the protective element, which again complicates the overall installation and increases the overall costs.

[0008] It would be desirable to come up with a solution for securing the electrical circuit, which protects against the occurrence and spread of fire in the circuit, reduces overall costs and is easy to install.

[0009] Summary of the Invention

[0010] The above stated shortcomings are eliminated by an electrical fuse comprising a body, two inlets for connecting wiring conductors and a heat-sensitive element for conductive connection of wiring conductors depending on temperature. All inlets and the heat-sensitive element are located in the body. The body also includes a carrier with extinguishing agent. The carrier preferably allows spontaneous release of the extinguishing agent from the carrier when the temperature rises above a certain value. This release can be ensured, for example, by melting a part of the carrier, by breaking a part of the carrier due to pressure increase caused by heating, by evaporation of the extinguishing agent, etc. Preferably, this release temperature is higher than the activation temperature of the heat-sensitive element, so that if the activation temperature of the heat-sensitive element is exceeded, the wiring conductors are disconnected or connected before the extinguishing is initiated.

[0011] Therefore, one electrical fuse fulfils both the safety function and the extinguishing function. One device thus protects the user from injury and the circuit from further damage, both due to electric current and fire. In the event of a fire in the circuit, the device can detect such a fire in the early stages, extinguish it and disconnect the device in the circuit from the electrical source. Depending on the choice of the heat-sensitive element, the device can disconnect the electrical circuit just before the fire occurs. There is no need for additional equipment, the installation of which is usually costly and time-consuming and requires additional surrounding modifications that require additional professional personnel (e.g. a bricklayer in addition to an electrical engineer).

[0012] The body is therefore the main carrier part of the fuse, which carries the other components of the fuse and possibly surrounds them. It can be, for example, made of plastic. The inlets are then elements that allow the wiring conductors to be brought from the outside of the fuse to the other components carried by the body - especially to the terminals of the heat-sensitive element - directly or indirectly via additional contacts. Alternatively, the inlets also mechanically secure the conductors to the body (e.g. as described in more detail below on the variant of inlets with a clip). The carrier is then the element that carries the extinguishing agent and ensures that the release of the extinguishing agent occurs only when it is desired. Its form is thus largely dependent on the type of the extinguishing agent (e.g. state of matter at normal temperature) and required application of the fuse.

[0013] The heat-sensitive element for conductive connection of wiring conductors depending on the temperature can connect these conductors in the initial state and interrupt this connection after its activation by increased temperature, or it can connect these conductors as a result of its activation by increased temperature, wherein in the default state it does not connect them. The choice of whether the increased temperature connects or disconnects the wiring conductors with the heat-sensitive element depends on the intended application of the fuse and is determined by the design of the fuse. A person skilled in the art knows, for example, that for a certain application under consideration, it is desirable to interrupt the phase conductor (or another wiring conductor, e.g. in a DC circuit) in the event of a fault, so that the wiring conductors are then phase conductors and the heat-sensitive element connects them in the initial state, so that it actually forms a part of the phase conductor (or other wiring conductor), and after activation it breaks this connection, whereby the downstream appliance or circuit is disconnected and its phase conductor is deenergized. For another application, the person skilled in the art knows that it is advisable to connect the neutral and grounding conductors in the event of a fault, so that the circuit breaker, which is not part of the fuse, but is part of the circuit to which the fuse is to be connected, disconnects this circuit from the voltage supply. In such an application, the heat-sensitive element does not connect the connected conductors under normal initial conditions, and in the event of a fault it is activated and connects them.

[0014] In other words, the conductive connection of wiring conductors depending on temperature is their connection from a certain temperature or their connection to a certain temperature.

[0015] The inlet for connecting wiring conductors may include at least one contact for connecting the wiring conductor and increasing conductivity, at least one inlet opening for the inlet of every wiring conductor into the body, and at least one retaining clip for pressing the wiring conductor to the contact. The presence of a contact for connecting the heat-sensitive element with the routed wiring conductors is particularly advantageous, but in some variants the wires can be routed directly to the terminals of the heat-sensitive element. Thus, one inlet can be intended for the inlet of multiple inlet wiring conductors and the other inlet can be used for the inlet of multiple outlet wiring conductors.

[0016] The inlet may include a storage cavity in the body of the electrical fuse, wherein at least one contact and at least one retaining clip may be stored in the storage cavity. The storage cavity is preferably of such a size that, in addition to the at least one contact and the at least one retaining clip, at least one wiring conductor can be inserted thereinto. One end of the inlet opening preferably opens out of the body of the electrical fuse into the surrounding environment and the other end of the inlet opening opens into the storage cavity.

[0017] The inlet opening can be in the shape of at least one cylinder for easy insertion of the wiring conductor. Preferably, the inlet opening has the axis of the inlet opening identical to the axis of this cylinder.

[0018] The inlet opening for the wiring conductor can include two cylindrical sections, wherein the first section has a larger diameter than the second section. The first section connects the surrounding environment with the inside of the electrical fuse body, and the second section connects the first section with the storage cavity in the electrical fuse body. The first section and the second section are preferably coaxial.

[0019] The first section may include a recess to facilitate the routing of the wiring conductor into the inlet opening. The recess is preferably at the interface of the first section and the surrounding environment.

[0020] There may be a chamfer between the first section and the second section for a smoother transition between these sections and for easier routing of the wiring conductor further into the inlet to the contact and the retaining clip for fixing this wiring conductor.

[0021] The first cylindrical section can have a larger cylinder diameter than the second cylindrical section. The first section can have diameter that is at least the same or greater (preferably the same diameter with clearance) than the diameter of the wiring conductor in the given part (preferably the wiring conductor with an insulating protective sheath). The second section can have diameter that is at least the same or larger (preferably the same with clearance) than the wiring conductor (preferably the conductive core of the wiring conductor). The diameters of the first section, the second section and the length of these sections thus preferably guide the user for the most efficient connection of the wiring conductor to the electrical fuse when inserting the wiring conductors into the electrical fuse.

[0022] The body can include two side walls that are connected by a common edge. This edge is rounded or chamfered to fit into the wiring box. Each inlet then includes a surface for contact with the wiring conductor. The surface for contact with the wiring conductor at the first inlet is not parallel to the area for contact with the wiring conductor at the second inlet. The surface for contact with the wiring conductor at the first inlet and the surface for contact with the wiring conductor at the second inlet converge towards the rounded or chamfered edge of the body. The surface for contact with the wiring conductor may be intended for contact with the insulation and / or for contact with the conductive core of the conductor. The advantage of this body shaping is that it fits better into a standard wiring box. The wiring conductors exit the fuse by diverging from each other, leaving space between them for other elements in the wiring box.

[0023] Alternatively, the surface for contact with the wiring conductor at the first inlet can be parallel to the surface for contact with the wiring conductor at the second inlet.

[0024] Alternatively, at least one axis of the inlet opening for one storage cavity may be parallel to at least one axis of the inlet opening for the second storage cavity.

[0025] Preferably, at least one surface for contact with the wiring conductor, preferably each surface, is a part of at least one contact. These converging surfaces are therefore used directly to connect the conductive cores of the conductors.

[0026] Preferably, the said edge is rounded to abut the inner wall of the wiring box. The angle between the side walls can be at least 90°. Preferably, the angle between the side walls depends on the size of the electrical fuse and the size of the wiring box for which the fuse is intended.

[0027] The opposite ends of each side wall that are not connected by a common edge preferably define the inlet side of the body that is offset from the common edge. The inlet side of the body includes at least one inlet opening for at least one wiring conductor at each side wall. Each inlet opening has its own axis. The axis of each inlet opening is preferably given by the centers of the cross-sections of the inlet opening. Preferably, one inlet opening is intended for one wiring conductor to prevent incorrect connection of the electrical fuse to the circuit due to incorrect connection of wiring conductors, incorrect routing of the wiring conductor to the inlet, etc.

[0028] For each side wall, the inlet side of the body includes, for example, four inlet openings for grounding conductors (for four cables or four bundles). The axis of each inlet opening in the inlet side of the body at one side wall is preferably parallel to the axis of each inlet opening in the inlet side of the body at the second side wall. The walls of the inlet openings therefore partially define the mutually converging surfaces for contact with the wiring conductor. Preferably, the axis of each inlet opening in the inlet side of the body at one side wall and the axis of the opposite inlet opening in the inlet side of the body at the second side wall form the same angle as the side walls, preferably form an angle with a tolerance of ±20° from the angle of the side wall, more preferably with a tolerance of ±10°.

[0029] The angle between the axis of each inlet opening at one side wall and the axis of the opposite inlet opening at the second side wall can be preferably selected from the range of 70- 160°.

[0030] The carrier with the extinguishing agent can be placed between the inlets. If the inlets include contacts, the carrier with the extinguishing agent can be placed between the contacts.

[0031] The carrier can be a tank that is a part of the body. The walls of the tank are therefore the walls of the body of the electrical fuse. The electrical fuse, together with the safety and extinguishing parts, is thus compact. The tank then surrounds the extinguishing agent and can close it. The release of the extinguishing agent may then require damaging some of the walls of the tank due to increased temperature. The design of the tank (material, thickness, etc.) then allows the selection of temperature at which the extinguishing agent is released; the direction in which the extinguishing agent is released; speed of release of extinguishing agent, etc.

[0032] The extinguishing agent in the tank can be preferably liquid or gaseous under normal storage conditions.

[0033] The extinguishing agent tank may have a discharge opening that faces in a different direction than the location of the heat-sensitive element to prevent sudden cooling of the heatsensitive element when extinguishing a fire. However, fuse variants are also possible, in which the tank has a discharge opening in any direction, i.e. for example also in direction of the heatsensitive element.

[0034] The extinguishing agent tank may include an openable wall for discharging the extinguishing agent when pressure (e.g. of the extinguishing agent) and / or heat is applied to this openable wall (whichever comes first). The required pressure for rupture of the openable wall can be achieved in the tank when heating the electric fuse - the extinguishing agent can expand after reaching a certain limit temperature (first evaporating in the case of liquid extinguishing agent or sublimating in case of solid extinguishing agent), which increases the pressure in the tank until the openable wall is broken. By direct heat application on the openable wall, the openable wall can be opened and the extinguishing agent can be discharged, for example, by burning through the openable wall, by melting, cracking or other degradation.

[0035] The openable wall can at least partially cover the discharge opening. Preferably, the body includes the lid, wherein the openable wall is a part of the lid that closes the discharge opening. The openable wall may include at least one area with a weakening for rupture of the extinguishing agent tank when pressure and / or heat is applied to the desired location. The openable wall may include at least one groove for tearing the openable wall by pressure from the tank and discharging the extinguishing agent at the desired location. The shape, length, depth and width of the groove can be selected depending on the required speed of extinguishing agent discharge. The weakening can therefore be a lower wall thickness, groove, weld (e.g. between the lid and another part of the electric fuse body), etc.

[0036] The groove can be in the middle part of the discharge opening. Preferably, the groove is located around the perimeter of the discharge opening. By placing the groove around the perimeter of the discharge opening, the entire lid can be removed and all the extinguishing agent can be discharged quickly. The openable wall can include multiple grooves, such as one groove in the center of the lid and second groove around the perimeter of the discharge opening.

[0037] A wall of the tank other than the wall covering the discharge opening can also be openable, for example, a fire can directly affect a certain part of the body of the electrical fuse so that the body burns through to the tank and discharges the extinguishing agent.

[0038] The openable wall can have a lower melting point than the material of rest of the body. When the ambient temperature increases due to a fire, the openable wall melts before the rest of the body and discharges the extinguishing agent. For example, the openable wall can have a melting point at least 20 °C lower than the material of the rest of the body.

[0039] The openable wall can be, for example, made of a material chosen from a range of materials including polystyrene, polymethyl methacrylate, polyethylene terephthalate, SAN, polypropylene, polyamide, polycarbonate or a combination thereof.

[0040] A tear in the openable wall can occur preferably under a pressure of at least 4 bar.

[0041] The carrier with the extinguishing agent can also be placed on the body of the electrical fuse (for example, glued). The carrier with the extinguishing agent may include a solid structure including the extinguishing agent, which is released by the application of heat or direct application of the flame.

[0042] The solid structure of the carrier can be the extinguishing agent in a solid state, which sublimates when a certain amount of heat is applied (preferably in a fire). The solid structure of the carrier may include pores with liquid or solid extinguishing agent.

[0043] The body of the electrical fuse may include a recess for the carrier with the extinguishing agent. Preferably, this recess includes the solid structure of the carrier including the extinguishing agent. At least one inlet for connection of the wiring conductor may include at least one retaining clip for mechanical connection of the wiring conductor to the heat-sensitive element and / or body.

[0044] The storage cavity preferably includes a contact for connecting each wiring conductor introduced into the particular inlet. The contact for connecting the wiring conductor helps to increase the conductivity between the inlets when they are connected by the heat-sensitive element.

[0045] The storage cavity can include multiple contacts, e.g., an individual contact for each wiring conductor, at at-least one inlet. The contacts at each inlet are then preferably connected to each other.

[0046] At least one contact may include multiple surfaces for contact with the wiring conductor when multiple wiring conductors of the same type are to be connected to it. These surfaces can be partially separated and at the same time conductively connected, so that when the temperature in the circuit rises, all connected parts of the circuit are interrupted.

[0047] The heat-sensitive element is preferably a temperature switch that allows the change of the state of the circuit (disconnect or connect), in which the electrical fuse can be installed, due to a change in ambient temperature.

[0048] The heat-sensitive element includes a functional member that is preferably chosen from a group including a bimetallic element for connecting wiring conductors when the temperature increases, a thermal fuse (which, on the other hand, disconnects the connected wiring conductors when the temperature increases) and a connecting conductor with a fusible insulator for isolating the connecting conductor from at least one wiring conductor (melting of the fusible insulator thus leads to the formation of conductive contact between the given wiring conductor and the connecting conductor when the temperature increases, so that the subsequently routed electrical conductors are connected, similarly to the bimetallic variant), more preferably from all wiring conductors.

[0049] In the initial (fault-free) state, the bimetallic element or connecting conductor can be connected to one wiring conductor (or corresponding contact thereof) and offset (or separated by the fusible insulator) from the second wiring conductor (or corresponding contact thereof). However, it can be offset from both, so that when the temperature rises, it is then routed into contact with both wiring conductors (directly or indirectly) and thus connects them. The bimetallic element can bend, expand or otherwise change its shape due to heat to connect wiring conductors.

[0050] The heat-sensitive element can be intended for contact with wiring conductors, in other words, in the event of a fault in the circuit (or, conversely, in the time up to the fault, as explained above), the heat-sensitive element can directly connect at least one first wiring conductor and at least one second wiring conductor.

[0051] The bimetallic element can also be in contact with at least one contact to which at least one wiring conductor can be conductively connected. Preferably, the bimetallic element in a fault state connects at least one contact conductively connected to at least one first wiring conductor and at least one contact conductively connected to at least one second wiring conductor. In other words, contacts are then used to connect the terminals of the heat-sensitive element with the wiring conductors, and the heat-sensitive element then connects / disconnects the contacts.

[0052] Alternatively, the bimetallic element can be in direct contact with at least one first wiring conductor. The bimetallic element is separated from every second wiring conductor. In a fault state, the bimetallic element connects at least one first wiring conductor to at least one second wiring conductor.

[0053] The inlet may include at least one electrical contact for conductive connection of at least one wiring conductor, wherein the bimetallic element may be firmly and conductively connected to the first contact. The second contact may include a surface for contact with the bimetallic element for connecting with the first contact to connect at least one first wiring conductor to at least one second wiring conductor. This variant can be structurally simpler and therefore cheaper to manufacture, because the bimetallic element is held in place in the body by a firm connection to one contact. Between the second end of the bimetal and the second contact, there is a gap that the bimetallic element bridges when heated and thus connects the contacts.

[0054] The inlet may include at least one electrical contact for conductive connection of at least one wiring conductor, wherein the heat-sensitive element may comprise two terminals. Each terminal is conductively connected to one of the contacts. The terminals can be connected by the bimetallic element. In other words, the terminals of the heat-sensitive element do not have to be directly the ends of the bimetallic element, but they can be additional conductive terminals, wherein the bimetallic element then connects these terminals (connected to the contacts / wiring conductors). This makes it possible to use, for example, a state-of-the-art bimetallic switch available on the market as the heat-sensitive element, wherein this switch is built into the body of the fuse according to the invention. Such a switch is to a certain extent an independent sub-unit of the fuse, so for example, to select the temperature at which the heat-sensitive element is to be activated, it is sufficient to replace the switches, and the rest of the fuse can always be the same.

[0055] Alternatively, each terminal can be conductively connected to one of the wiring conductors, wherein the terminals can be connected by the bimetallic element. This is then the variant described above, but without the use of contacts. The variant without contacts may generally be cheaper, but there may be higher electrical resistance between the terminals of the heat-sensitive element and the wiring conductors. Alternatively, in case of the variant without contacts, it may also be more difficult to attach the wiring conductors to the fuse inlets.

[0056] The heat-sensitive element can include two terminals, wherein each terminal is connected to one of the inlets. The terminals can be connected by the bimetallic element. Furthermore, at least one inlet (but preferably all inlets for easier installation of the fuse) includes at least one retaining clip, which includes a base, a flexible first arm for pressing the at least one wiring conductor against the base, and a flexible second arm for pressing the corresponding terminal against the base. The conductive connection of the terminal and the at least one wiring conductor is preferably implemented by the retaining clip. The clip can also include a contact, or the base of the clip can serve as a contact (see below).

[0057] Alternatively, the retaining clip may include a flexible first arm for pressing against the terminal and a flexible second arm for pressing against the at least one wiring conductor. The terminal and the wiring conductor can be pressed together by the first arm and the second arm. The current does not have to be led through the fuse (the base thereof) but can be directly led between the terminal and the wiring conductor.

[0058] Preferably, the base includes a surface for laying the contact. Preferably, at least one inlet therefore includes at least one contact and at least one retaining clip including the base, the flexible first arm to press the at least one wiring conductor against the contact, and the flexible second arm to press the corresponding terminal against the contact.

[0059] The retaining clip is preferably made of a single piece of sheet metal. This makes it cheap to manufacture, and the choice of sheet metal material or thickness thereof can affect the pressure force of the arms.

[0060] The retaining clip may include at least one opening to reduce the weight of the retaining clip and thus the entire electrical fuse.

[0061] The retaining clip can be a part of the contact, e.g. a part of the bent sheet metal of the contact. In principle, the contact and the clip are made of one piece of material, which ensures better current conduction and mechanical retention of the wiring conductor, or even the terminal of the heat-sensitive element.

[0062] The body may include a groove for the retaining clip for attaching the retaining clip to the body. The clip can then be held in the body mechanically, which makes it easier and cheaper to manufacture the fuse.

[0063] The retaining clip may include at least one shorter arm for attachment to the electrical fuse body and at least one longer arm for pressing the wiring conductor, preferably against the contact. Together, one shorter arm and one adjacent longer arm serve to press at least one wiring conductor, preferably exactly one wiring conductor.

[0064] Alternatively, the retaining clip may include at least one longer arm for attachment to the electrical fuse body and at least one shorter arm to press the wiring conductor, preferably against the contact. More generally, the clip can include at least one arm, more preferably at least two, which are used to brace it in the body, wherein a part of this conductor is inserted under one of the arms (between the arm and the body / contact / other part of the clip, etc.) when the wiring conductor is inserted, thus holding the clips in place by preloading. The length of the arms is then affected by the design of the surrounding parts of the fuse.

[0065] The retaining clip may include a base for attaching the retaining clip to the contact.

[0066] At least one arm can be pre-sprung for easy and firm attachment of at least one wiring conductor.

[0067] The heat-sensitive element may include a permanently deformable member for permanent conductive connection of wiring conductors after thermal deformation of the bimetallic element. The member for permanent conductive connection has a lower modulus of elasticity than the bimetallic element, so that even if the bimetallic element no longer presses on the member for permanent conductive connection (e.g. when the ambient temperature decreases, when the bimetallic element can return to its original position), the member for permanent conductive connection remains deformed and conductively connects the wiring conductors.

[0068] Preferably, the permanently deformable member for permanent conductive connection is intended for conductive connection of the contacts.

[0069] The member for permanent conductive connection can be a part of the bimetallic element so that the bimetallic element remains in a deformed state after activation without the need for another auxiliary component, e.g. the bimetallic element can be a one-way one.

[0070] The advantage of using this member for permanent conductive connection is that after the temperature has been decreased / the fire has been extinguished, the heat-sensitive element cannot be deactivated again, i.e. the voltage cannot be reapplied to the downstream circuit / appliance even if the fault has not yet been resolved. The member for permanent conductive connection can thus significantly increase the safety of the fuse.

[0071] The heat-sensitive element may include a connecting conductor with a fusible insulator to isolate the connecting conductor from the at least one wiring conductor. The heat-sensitive element further includes a pre-sprung element for pressing a part of the connecting conductor to the fusible insulator. After loosening of the fusible insulator, the pre-sprung element presses the parts of the connecting conductor to the at least one wiring conductor (directly and / or indirectly, for example, through the contact and / or the retaining clip). Thus, depending on the strength of the flexible element and the material of the fusible insulator, at a certain temperature, the fusible insulator softens sufficiently so that the connecting conductor is pressed through the flexible element into contact with the wiring conductor / clip / contact, etc.

[0072] The pre-sprung element can be a spring, preferably attached to the body of the electrical fuse. The connecting conductor can be permanently connected to the second one of the wiring conductors, or it can be separated from it by the fusible insulator in the same way as from the first conductor.

[0073] Preferably, the pre-sprung element is a part of the connecting conductor, e.g. a coiled flexible sheet metal, which leads to a reduction in the weight and size of the electrical fuse. The flexible connecting conductor can be pressed against the fusible insulator by the body of the electrical fuse, i.e. the flexible connecting conductor or flexible element is braced between the body and the wiring conductor / clip / contact. After degradation of the fusible insulator, the connecting conductor conductively connects the wiring conductors due to its flexible properties, preferably via contacts.

[0074] In a fault-free state of the circuit, the connecting conductor can be connected to at least one contact for at least one first wiring conductor, while it is separated from each contact for at least one second wiring conductor by the fusible insulator.

[0075] In a fault-free state of the circuit, the member for permanent conductive connection may be connected to at least one contact for at least one first wiring conductor, while it is separated from each contact for at least one second wiring conductor to prevent these contacts from being connected. Alternatively, in a fault-free state of the circuit, the member for permanent conductive connection can be connected to at least one first wiring conductor, while it is separated from each second wiring conductor so that every first wiring conductor is not connected to any second wiring conductor.

[0076] The bimetallic element can be connected to at least one contact for at least one first wiring conductor, while it is separated from each contact for the second wiring conductor.

[0077] Preferably, the electrical fuse comprising the bimetallic element as a part of the heatsensitive element is designed for connection of at least one neutral conductor and at least one grounding conductor. Preferably, the electrical fuse comprising the connecting conductor with the fusible insulator as part of the heat-sensitive element is designed for connection of at least one neutral conductor and at least one grounding conductor.

[0078] The heat-sensitive element may include a thermal fuse. The electrical fuse with the thermal fuse is particularly advantageous for placement in electrical circuits with no residual current circuit breaker connected.

[0079] The thermal fuse can include a conductive jacket, a conductive sliding partition, a flexible element, and a fusible insert. The conductive sliding partition, the flexible element and the fusible insert are located in the conductive jacket. The flexible element is located between the conductive sliding partition and the fusible insert. The flexible element maintains a certain distance between the sliding partition and the fusible insert. The position of the sliding partition depends on the condition of the fusible insert. Degradation (e.g. by melting, softening, cracking) of the fusible insert moves the sliding partition for disconnecting the conductive connection of the wiring conductors. Degradation of the fusible insert occurs due to heat. The conductive sliding partition includes a surface for contact with the first wiring conductor (preferably the phase conductor) and the conductive jacket includes a surface for contact with the second wiring conductor (preferably the phase conductor).

[0080] The at least one inlet may include the retaining clip to press the thermal fuse terminal to the wiring conductor, preferably to the phase conductor. This clip can be realized and can provide the same advantages as described above for the clip, especially for the bimetallic variant of the fuse.

[0081] Preferably, the electrical fuse including the thermal fuse as a part of the heat-sensitive element is designed for connection of at least two phase conductors, wherein at least one phase conductor is an inlet conductor and at least one phase conductor is an outlet conductor.

[0082] The heat-sensitive element can preferably have an activation temperature in the range of 45-80 °C. The activation temperature of the heat-sensitive element is the temperature at which the heat-sensitive element disconnects the circuit after the installation of the electrical fuse in the circuit. Thus, in case of the heat-sensitive element including the bimetallic element and / or the connecting conductor with the fusible insulator, it is the temperature at which the wiring conductors are connected, in case of the heat-sensitive element including the thermal fuse, it is the temperature at which the wiring conductors are disconnected.

[0083] The heat-sensitive element can have an activation temperature in the range of 45-60 °C for house wiring. The heat-sensitive element can have an activation temperature in the range of 60-80 °C for placement in the vehicle's electrical wiring. The heat-sensitive element can have an activation temperature ranging from (-50) to (-1) °C for the use of the electrical fuse in a low temperature environment. The activation temperature of the heat-sensitive element is preferably selected according to the ambient conditions in the environment in which the electrical fuse is intended to be used.

[0084] The extinguishing agent can be stored in the carrier in a liquid state, gaseous state or solid state. Preferably, the extinguishing agent changes its state to gaseous before extinguishing. The extinguishing agent can have a temperature of transformation into a gaseous state in the range of 45-90 °C, more preferably in the range of 48-70 °C. These temperatures are particularly practical for standard applications (homes, offices, etc.).

[0085] The extinguishing agent can also have a temperature of transformation into a gaseous state, e.g. in the range of (-50) to (-1) °C. The electrical fuse can then be used also in low- temperature environments, e.g. in areas beyond the Arctic Circle. Hexafluoropropane, heptafluoropropane, etc. can be used as the extinguishing agent when using the electrical fuse at low ambient temperatures.

[0086] Preferably, the temperature of the extinguishing agent for transformation into a gaseous state for extinguishing is lower than the activation temperature of the heat-sensitive element, so that when the heat-sensitive element is activated, the electrical fuse is ready for eventual discharge of the extinguishing agent. The electrical fuse thus first disconnects the circuit to prevent further damage, and then discharges the extinguishing agent and extinguishes any fire.

[0087] The extinguishing agent for standard ambient temperatures can be FK-5-1 -12 (known as Novec), heptafluoropropane or other extinguishing substances. Preferably, the extinguishing agent is harmless to health and gentle to electronics, so that the electronic elements located in the area being extinguished are not damaged by the extinguishing agent, which also helps to reduce the overall damage during the fire. The extinguishing agent may have a specific odor for easier indication of a fault in the circuit.

[0088] The retaining clip can be made of a material chosen from a group including spring steel, beryllium copper or other flexible materials. Thanks to the flexibility of the retaining clip, wiring conductors of different diameters can be attached in one electrical fuse.

[0089] Alternatively, the electrical fuse may include an element for mechanical attachment of the wiring conductor, e.g. by means of screw connection, standard terminal block, etc.

[0090] The contact is preferably made of a material with good electrical conductivity. The contact can be made of a variety of materials including copper and alloys thereof, aluminum and alloys thereof, etc. The contact can be plated to increase the contact conductivity, to suppress corrosion, etc. The connecting conductor can be made of a variety of materials, including spring steel, beryllium copper, or other flexible materials.

[0091] The fusible insulator can have a low material degradation temperature, such as melting, softening, cracking, etc., so that the connecting conductor establishes conductive connection with the wiring conductors. The activation temperature of the heat-sensitive element including the connecting conductor, the fusible insulator and the pre-sprung element can be influenced by the degradation temperature of the fusible insulator material, the choice of the stiffness of the presprung element, the degree of pre-springing of the connecting conductor, combination thereof, etc. Thus, for example, the fusible insulator may have a higher material degradation temperature when the connecting conductor is pre-sprung so that the connecting conductor presses through the fusible insulator and thus establishes conductive connection between the wiring conductors.

[0092] The fusible insulator can be made of a variety of materials with a low melting temperature - e.g. paraffin, carnauba wax, plastic, hot melt adhesive. The melting point of the fusible insulator can preferably be in the range of 50-90 °C.

[0093] The body can be made of a variety of materials including polystyrene, PMMA, PET, SAN, etc. Preferably, the body of the electric fuse is transparent for easy visual inspection of whether there is extinguishing agent in the tank, whether the electrical fuse has already been activated (bent bimetallic element, connecting conductor, etc.), etc.

[0094] The fusible insert of the thermal fuse can be made of a variety of materials including polydecamethylene sebacate (preferably with a degradation temperature of approximately 80 °C), polydecamethylene adipate (preferably with a degradation temperature of approximately 80 °C), chloroprene rubber (preferably with a degradation temperature of approximately 80 °C), poly-1 - dodecane (preferably with a degradation temperature of approximately 76 °C), polyethylene sebacate (preferably with a degradation temperature of approximately 76 °C), polyvinyl-n-propyl ether (preferably with a degradation temperature of approximately 76 °C), etc.

[0095] At least one electrical fuse can be part of a wiring system that includes a wiring box and wiring conductors. Preferably, the wiring conductor for connection to the electrical fuse is from a group including at least one phase conductor, at least one grounding conductor and at least one neutral conductor. The electrical fuse is preferably located in the wiring box, which can be, for example, an electrical back box, a junction box, etc.

[0096] The first wiring conductor and the second wiring conductor can be selected from a group including a neutral conductor and a grounding conductor, preferably in case of the electrical fuse including the functional member of the bimetallic element and / or the connecting conductor with the fusible insulator. Thus, the first wiring conductor can be the neutral conductor, while the second wiring conductor can be the grounding conductor, or the first wiring conductor can be the grounding conductor, and the second wiring conductor can be the neutral conductor.

[0097] A separate conductor cable and / or conductor cable bundles may be connected to the electrical fuse. The wiring conductor can include a conductive core and an insulating shell of the conductive core.

[0098] The wiring conductor can contact the heat-sensitive element with its conductive core. The wiring conductor can contact at least one contact of the electrical fuse body with its conductive core.

[0099] The carrier can include a quantity of extinguishing agent for filling the wiring box with a concentration of preferably at least 4%, more preferably at least 6%.

[0100] The wiring system can include at least one residual current device, wherein the first wiring conductor in this system is the neutral conductor and the second wiring conductor is the grounding conductor. Alternatively, the first wiring conductor can be the grounding conductor and the second wiring conductor can be the neutral conductor. In the circuit with the residual current device, the electrical fuse, preferably including the heat-sensitive element including the bimetallic element and / or the connecting conductor with the fusible insulator, can be used to disconnect the circuit when the neutral conductor is conductively connected with the grounding conductor.

[0101] The wiring system can further include a power source, a socket, at least one appliance to enable current to be drawn from the source in the connected circuit.

[0102] The electrical fuse including the thermal fuse as the main functional member can have at least one phase conductor connected to each inlet.

[0103] The wiring system may include at least one electrical fuse, preferably including the bimetallic element, and at least two wiring conductors - at least one first wiring conductor and at least one second wiring conductor. The at least one first wiring conductor is attached in one inlet of the electrical fuse and is conductively connected to the heat-sensitive element. The at least one second wiring conductor is attached in the second inlet of the electrical fuse and is conductively connected to the heat-sensitive element.

[0104] The electrical fuse, which includes the heat-sensitive element including the bimetallic element, may be a part of the electrical system. Every first wiring conductor is attached in the first inlet to the heat-sensitive element, more preferably to the contact with the retaining clip. Every second wiring conductor is attached in the second inlet to the heat-sensitive element, more preferably to the contact with the retaining clip. The electrical system has two states: a fault-free state and a fault state. In the fault-free state, every first wiring conductor is isolated from every second wiring conductor. In the fault state, every first wiring conductor is conductively connected to every second wiring conductor due to the change in the shape of the bimetallic element due to heat. Preferably, the electrical system includes at least one residual current device. In the fault state, by connecting the first wiring conductor and the second wiring conductor in the system with the residual current device, the flow of electric current is interrupted.

[0105] The electrical fuse, which includes the heat-sensitive element including the connecting conductor, with the fusible insulator, can be part of an electrical system. Every first wiring conductor is attached in the first inlet to the heat-sensitive element, more preferably to the contact with the retaining clip. Every second wiring conductor is attached in the second inlet to the heatsensitive element, more preferably to the contact with the retaining clip. The electrical system has two states: a fault-free state and a fault state. In the fault-free state, every first electrical conductor is isolated from every second wiring conductor. In the fault state, every first wiring conductor is conductively connected to every second wiring conductor due to the degradation of the fusible insulator due to heat. Preferably, the electrical system includes at least one residual current device. In the fault state, by connecting the first wiring conductor and the second wiring conductor in the system with the residual current device, the flow of electric current is interrupted.

[0106] The electrical fuse, which includes the heat-sensitive element including the thermal fuse, can be part of an electrical system. Every first wiring conductor is attached in the first inlet to the heat-sensitive element, more preferably to the contact with the retaining clip. Every second wiring conductor is attached in the second inlet to the heat-sensitive element, more preferably to the contact with the retaining clip. The electrical system has two states: a fault-free state and a fault state. In the fault-free state, every first wiring conductor is conductively connected to every second wiring conductor. In the fault state, every first wiring conductor is disconnected with every second wiring conductor due to the activation of the thermal fuse (disconnection of terminals thereof) by heat.

[0107] In the fault state, the bimetallic element can contact each contact and retaining clip, preferably also the wiring conductor, at each inlet, for more efficient conductive connection of wiring conductors at all inlets.

[0108] In the fault state, the member for permanent conductive connection can contact each contact and retaining clip, preferably also the wiring conductor, at each inlet, for more efficient conductive connection of wiring conductors at all inlets.

[0109] In the fault state, the connecting conductor can contact each contact and retaining clip, preferably also the wiring conductor, at each inlet, for more efficient conductive connection of the wiring conductors at all inlets. In the electrical system, preferably in the junction box, at least one grounding conductor and at least one neutral conductor as inlet conductors and at least one additional grounding conductor and at least one additional neutral conductor as an outlet conductors can be connected to the electrical fuse, which are then routed from the junction box to other appliances, sockets, etc. There can be more outlet conductors than inlet conductors, e.g. one inlet conductor and three outlet conductors. Alternatively, there may be more inlet conductors than outlet conductors. Alternatively, there may be the same number of outlet conductors as inlet conductors, e.g. two inlet conductors and two outlet conductors.

[0110] Description of Drawings

[0111] The essence of the invention is further explained by exemplary embodiments thereof, which are described using the accompanying drawings, in which:

[0112] Fig. 1 shows a plan view of an electrical fuse including a bimetallic element and a member for permanent conductive connection.

[0113] Fig. 2 is an A-A cross-section of the electrical fuse with the plane marked in Fig. 1 ,

[0114] Fig. 3 shows an isometric view of the connection of wiring conductors to the heatsensitive element, including the bimetallic element and the member for permanent conductive connection in a fault-free state,

[0115] Fig. 4 is a side view of the retaining clip and the contact of the electrical fuse shown in Fig. 3,

[0116] Fig. 5 is a front view of the connection of wiring conductors to the heat-sensitive element including the bimetallic element and the member for permanent conductive connection in a fault state,

[0117] Fig. 6 is an isometric view of the connection of wiring conductors to the heat-sensitive element including the bimetallic element and the member for permanent conductive connection in a fault state,

[0118] Fig. 7 is an isometric view of the electrical fuse with visible arrangement of the electrical fuse elements in the body through a horizontally guided section perpendicular to the height of the cylindrical body of the electric fuse, Fig. 8 is an isometric view of the heat-sensitive element in a fault-free state including the bimetallic element firmly connected to the contact,

[0119] Fig. 9 is a plan view of the heat-sensitive element in a fault-free state including the bimetallic element firmly connected to the contact,

[0120] Fig. 10 is an isometric view of the heat-sensitive element in a fault state including the bimetallic element firmly connected to the contact,

[0121] Fig. 11 is a plan view of the heat-sensitive element in a fault state including the bimetallic element firmly connected to the contact,

[0122] Fig. 12 is an isometric view of the embodiment of the contacts with retaining clips,

[0123] Fig. 13 is an isometric view of the contacts with retaining clips,

[0124] Fig. 14 is an isometric view of the embodiment of the contacts with retaining clips,

[0125] Fig. 15 is a plan view of the electrical fuse including the fusible insulator,

[0126] Fig. 16 is a B-B cross-section of the plane marked in Fig. 15 of the electrical fuse with the connecting conductor and the fusible insulator,

[0127] Fig. 17 is an isometric view of the connection of wiring conductors to the heatsensitive element including the connecting conductor and the fusible insulator in a fault-free state,

[0128] Fig. 18 is an isometric view of the connection of wiring conductors to the heatsensitive element including the connecting conductor and the fusible insulator in a fault state,

[0129] Fig. 19 is a front view of the connection of wiring conductors to the heat-sensitive element including the connecting conductor and the fusible insulator in a fault state,

[0130] Fig. 20 is a side view of the electrical fuse including the bimetallic element and the terminals of the heat-sensitive element,

[0131] Fig. 21 is a C-C cross-section of the plane marked in Fig. 20 of the electrical fuse with the bimetallic element and terminals for connection to the wiring conductors,

[0132] Fig. 22 is an isometric view of the heat-sensitive element including the bimetallic element and the terminals connected with the wiring conductors,

[0133] Fig. 23 is an isometric view of the contact and the retaining clip including a first arm, a second arm and a base, Fig. 24 is an isometric view of the connection of wiring conductors to the heatsensitive element including the bimetallic element,

[0134] Fig. 25 is the front view of the connection of the wiring conductors to the heatsensitive element including the bimetallic element,

[0135] Fig. 26 is an isometric view of the electrical fuse including a carrier with extinguishing agent on the inlet side of the body and the retaining clips implemented as Wago clamp,

[0136] Fig. 27 is a cross-section of the electrical fuse including the thermal fuse, wherein the plane of the cross-section is vertical and passes through the center of the electrical fuse,

[0137] Fig. 28 is a plan view of the electrical fuse with a spring bimetallic element,

[0138] Fig. 29 is a D-D cross-section of the plane marked in Fig. 28 of the electrical fuse with the bimetallic element in the form of a spring,

[0139] Fig. 30 is a plan view of the connection of wiring conductors to the heat-sensitive element including the spring bimetallic element in a fault-free state,

[0140] Fig. 31 is a plan view of the connection of wiring conductors to the heat-sensitive element including the spring bimetallic element in a fault state,

[0141] Fig. 32 is a plan view of the electrical fuse with the bimetallic element in the form of a strip, and

[0142] Fig. 33 is an E-E cross-section of the plane marked in Fig. 32 of the electrical fuse with the bimetallic element in the form of a strip.

[0143] Exemplary Embodiments of the Invention

[0144] The electrical fuse will be further explained by means of exemplary embodiments with reference to the relevant drawings. The first exemplary embodiment of the electric fuse and the arrangement thereof is shown in Fig. 1-6 (the inlet opening 22 is not shown in these drawings).

[0145] The electrical fuse includes a body 1, at least two inlets (or outlets) for connecting wiring conductors, a heat-sensitive element 2, which is intended for conductive connection of electrical conductors (directly or indirectly via contacts 4) depending on the temperature, and further includes a carrier 3 with extinguishing agent, which is a part of the body 1. The inlets and the heat-sensitive element 2 are located in the body T The heat-sensitive element 2 is a temperature switch that reacts to the ambient temperature in a certain way.

[0146] Each inlet in the first exemplary embodiment includes a contact 4, a retaining clip 14 and an inlet opening 22 in the body 1 of the fuse.

[0147] In the first exemplary embodiment, the heat-sensitive element 2 includes a bimetallic element 8 as the main functional member. The bimetallic element 8 here has the shape of a circle with an opening in the center of the circle for fixing to the body 1 of the fuse, as can be seen in Fig. 2 and Fig. 3. This opening has a square shape to secure the bimetallic element 8 more firmly in the body 1 than if the opening had a circular cross-section. The heat-sensitive element 2 also includes a permanently deformable member 21 for permanent conductive connection, which here takes the form of a strip of copper sheet metal. The member 21 for permanent conductive connection is located near the bimetallic element 8 so that the center of the bimetallic element 8 touches the center of the member 21 for permanent connection. Thus, the bimetallic element 8 is convex towards the member 21 for permanent connection in the resting state such that the edges of the bimetallic element 8 (outer circle) do not touch the member 21 for permanent conductive connection, as can be seen in Fig. 2 and Fig. 3. One end of the strip (of the member 21 for permanent conductive connection) points to one contact 4 and the other end of the strip points to the other contact 4. The strip is fixed in its center to the body 1 of the fuse. The member 21 for permanent conductive connection includes two protrusions pointing to the bimetallic element 8, which are located, when the strip is attached, in the center symmetrically with respect to the plane perpendicular to the section plane (A-A) passing through the center of the member 21 for permanent conductive connection, as shown in Fig. 2. Thus, one protrusion is located on the part of the strip facing one contact 4, and the other protrusion is located on the part facing the other contact 4. Both protrusions are in contact with the bimetallic element 8. These protrusions help with bending of the member 21 for permanent conductive connection when bending the bimetallic element 8. Both ends of the strip (member 21 for permanent conductive connection) are located at such a distance from both contacts 4 that after the deformation of the strip caused by the bimetallic element 8, both ends of the strip contact both contacts 4, as shown in Fig. 5 and Fig. 6.

[0148] The wiring conductors in the first exemplary embodiment are a neutral conductor 18, marked in blue, and a protective (grounding) conductor 19, marked in green-yellow. In the first exemplary embodiment, four neutral conductors 18 cables and four grounding conductors 19 cables are connected to the fuse. As a standard, the wiring conductor includes a protective non- conductive sheath that encloses the conductive part of the wiring conductor - the wires - and protects the user from injury. In the first exemplary embodiment, only the conductive part of the wiring conductor is routed to the contact 4 and pressed by the retaining clip 14.

[0149] The first exemplary embodiment includes two contacts 4 in the form of two copper plates with a rectangular cross-section, which are fixed in the body 1 of the fuse symmetrically with respect to a plane perpendicular to the section plane (A-A) passing through the center of the body, the center of the bimetallic element 8, the center of the member 21 for permanent conductive connection, etc. The contact 4 is used to increase the conductive surface area (and thus to improve the effectiveness of the electrical fuse) in the conductive connection between two different wiring conductors (specifically the neutral conductor 18 and the grounding conductor 1_9) and to ensure the connection of multiple conductors of the same type to one electrical fuse. When installing the electrical fuse in the electrical circuit, there are four neutral conductors 18 connected to one contact 4 and four grounding conductors 19 connected to the second contact 4_of the fuse according to the first exemplary embodiment. Each contact 4 here includes the surface for contact with the wiring conductor - a rectangular surface that is in direct contact with the wiring conductors after the fuse is installed in the electrical circuit.

[0150] Four retaining clips 14 are fixed to each contact 4 to attach and press the individual conductors to the contact 4. The retaining clip 14 is made of a flexible and electrically conductive material, in this example spring steel, to elastically attach the wires to the contact 4. The retaining clip 14 has a J-shaped cross-section, as can be seen in Fig. 4, braced on the side of the longer arm against the body 1 of the fuse and on the side of the shorter arm against the contact 4. The shorter arm is used to attach and press the conductor to the contact 4_when the conductor is inserted between the end of the shorter arm and the contact 4, which pre-springs the shorter arm. Due to the elastic properties of the material of the retaining clip 14, when inserting the wiring conductor, the shorter arm is first compressed, which then exerts an elastic force on the wiring conductor and presses it to the contact 4. In the orientation according to Fig. 4, the conductor is thus inserted between the retaining clip 14 and the contact 4 towards the left and upwards. By pressing the wiring conductor by the retaining clip 14 against the contact 4, the contact area of the wiring conductor with the contact 4 is increased, which leads to improved conductivity between the contacts 4 (and thus also the wiring conductors) in the event of a fault condition in the circuit. The amount of the pressure force of the wiring conductor, which is given by the design of the retaining clip 14, the material of the retaining clip 14, the thickness of the wiring conductor, etc., can therefore affect the effectiveness of the electrical fuse in the circuit, especially for the activation of the residual current circuit breaker. The shorter arm is terminated with a rounded shaped surface for better contact with the conductor. In the first exemplary embodiment, the longer arms of the four retaining clips 14 are connected for each contact 4. Both four-sets of the retaining clips 14 are therefore made of one piece of material. In the first exemplary embodiment, the outside of the body 1 is approximately crescentshaped when viewed perpendicular to the routed conductors, as can be seen in Fig. 1 . The body 1 includes two side walls 6 that are connected by a common rounded edge 7. The rounding radius of the edge 7 is chosen so that the body 1 of the fuse abuts the inner wall of cylindrical wiring boxes, for example the wall of the electrical back box under a socket, with standard dimensions. The angle between the side walls 6 is chosen so that when installing the fuse in the socket back box, the connected wiring conductors (the grounding conductor 19 and the neutral conductor 1.8) run as close as possible to the wall of the electrical back box and at the same time the wiring conductors at the inlet opening 22 in the body 1 of the fuse do not "break". In the first exemplary embodiment, this angle is approximately 120°. Thus, the rounding radius of the edge 7 and the angle between the side walls 6 allow the grounding conductors 19 and the neutral conductors 8 to be routed as close as possible to the wall of the wiring box, freeing up space in the center of the box where other components can be more easily connected, such as phase conductors 20 to the terminals, etc.

[0151] The inlet side of the body 1 includes cylindrical inlet openings 22 through which the wiring conductors pass and are attached after the installation of the electrical fuse. The inlet openings 22 are located at the ends of the side walls 6, which are not connected by the common edge 7. The axis of the inlet opening 22 is given by the cross-section centers of the inlet openings 22, in the first exemplary embodiment this axis is the axis of the cylinder. At the end of one side wall 6, the inlet side of the body in the first exemplary embodiment includes four inlet openings 22 for the grounding conductors 19 (for four cables or four bundles). At the end of the second side wall 6, the inlet side of the body 1 similarly includes four inlet openings 22 for the neutral conductors 1.8. The axes of the inlet openings 22 at the end of the one side wall 6 are parallel to the axes of the inlet openings 22 at the end of the second side wall 6 and form the same angle as the side walls 6.

[0152] At each side wall 6_in the body 1, there is one contact 4 with the retaining clip 14. The body 1 thus includes at both side walls 6 inlet openings 22 for wiring conductors and a storage cavity 23 for wiring conductors attached to the contact 4 with the retaining clip 14. The contact 4 is held in the groove for the contact 4 in the storage cavity 23 and the retaining clip 14 is held in the groove for the retaining clip 14. At the same time, the contact 4 is pressed to one wall of the storage cavity 23 by the retaining clip 14, which is pressed to the other wall of the storage cavity 23, specifically by the longer arm thereof, by the interaction of the contact 4 on the retaining clip 14 (and thanks to the elastic properties thereof). At the connection of the longer arm and the shorter arm of the retaining clip 14, there is a clearance between the retaining clip 14 and the wall of the storage cavity 23 to allow the retaining clip 14 to be compressed when the wiring conductor is inserted. Due to this interaction of the contact 4 and the retaining clip 14, both the contact 4 and the retaining clip 14 are fixed to the body 1 of the fuse and do not need to be further fastened with fastening elements or otherwise additionally fastened (e.g. glued).

[0153] Furthermore, the storage cavity 23 includes an opening for the contact 4 to pass through to the heat-sensitive element 2. The heat-sensitive element 2 is housed in the body 1 , in the opening for the heat-sensitive element 2. This opening includes protrusion of the body 1 of the electrical fuse attaching the bimetallic element 8 and the member 21 for permanent conductive connection of the contacts 4 to the body T Between the storage cavities 23 at the side walls 6 there is the carrier 3 with extinguishing agent in the form of a tank. The extinguishing agent tank has one wall in the body 1 of the fuse that can be opened for discharging the extinguishing agent. This openable wall 5 is located on the opposite side to the heat-sensitive element 2. The body 1 in the first exemplary embodiment includes three main parts that are connected. The first part contains the contacts 4, the extinguishing agent tank, the retaining clips 14, etc. The second part contains the heat-sensitive element 2, wherein the first part and the second part are not completely separated (e.g. by walls) to allow the contact of the heat-sensitive element 2 with the contacts 4. The third part is the lid at the discharge opening of the tank including the openable wall 5. This lid is made of a material with a low melting point, so that in the event of fire in the circuit, the lid quickly melts and discharges the extinguishing agent. At the same time, the lid is fitted to the discharge opening and fixed to the body so that when the pressure in the tank increases to the required predetermined value (approximately 4 bar), this lid is ejected from the rest of the body 1 and the extinguishing agent is discharged.

[0154] The body 1 is made of non-conductive material for protection of persons when handling the connected electrical fuse in the electrical circuit. In the first exemplary embodiment, the body 1 is made of transparent polycarbonate. Thanks to its transparency, it is possible to quickly and easily check the condition of the electrical fuse - whether it includes extinguishing agent, whether the permanently deformable member 21 for permanent connection of conductors has already been deformed, whether the contacts 4 are properly fastened, etc.

[0155] In the first exemplary embodiment, a liquid extinguishing agent is used as the extinguishing agent, which changes its state to gaseous before discharge and thus covers more volume of space due to its volume in liquid form, such as Novec. The extinguishing agent is harmless to health and gentle to electronic components, so there is no damage to other undamaged electronic components during extinguishing, which helps to reduce the overall damage in a fire.

[0156] The electrical fuse is used for connection into the electrical circuit, where it interrupts the flow of current in the event of a fault in the circuit and extinguishes fire in the event of a larger temperature rise and fire. The electrical fuse thus has a safety function and an extinguishing function in one body 1. The electrical fuse can therefore be installed in various wiring boxes, such as wall junction boxes, electrical back boxes, etc., where fires often occur, for example, due to poorly tightened contact. The exemplary installation and function of the fuse in the first exemplary embodiment can be carried out in the following way. Four neutral conductors 18 and four grounding conductors 19 are connected to the fuse in the wiring box, and the electrical fuse is placed in the box. In the event of a fault in the circuit, there is an increase in heat that is applied on the fuse, specifically on the heat-sensitive element 2. Due to this increase in heat, the bimetallic element 8 bends to the opposite side (towards the member 21 for permanent conductive connection and towards the tank), thus pressing on the member 21 for permanent conductive connection, which bends towards the contacts 4 until the member 21 for permanent conductive connection contacts both contacts 4.

[0157] In the first exemplary embodiment, the member 21 for permanent conductive connection contacts the contacts 4 together with the retaining clips 14 as shown for example in Fig. 5, to ensure the best possible conductive connection between the contacts 4. When connecting the contacts 4, the grounding conductors 19 and the neutral conductors 18 are connected and the circuit with the residual current device is interrupted. If there the temperature is no longer rising, but it is cooling down, the bimetallic element 8 can bend back to its original position. However, thanks to the member 21 for permanent conductive connection, the neutral conductors 18 and the grounding conductors 19 are still connected, and therefore the circuit cannot be reconnected, which could lead to a more serious fault, fire, etc. If the temperature rises even after the disconnection or if, for example, there has been a sharp increase in temperature before the disconnection, the extinguishing agent will be discharged into the space of the wiring box. The discharging can occur, for example, in such a way that the lid closing the discharge opening of the extinguishing agent tank melts due to the direct action of fire, or in the extinguishing agent tank, the pressure in the tank increases due to the expanding extinguishing agent until the lid is knocked out or broken. The electrical fuse is thus able to extinguish the fire in the circuit regardless of whether the circuit is disconnected or not. After use, the electrical fuse is removed from the circuit and can be replaced with a new one.

[0158] In the second exemplary embodiment, which is shown in Fig. 15-19, the electrical fuse includes the carrier 3 with the extinguishing agent in the form of a tank and the inlet that includes the contact 4, the retaining clip 14 and the inlet opening 22 in the body 1 of the electrical fuse, similarly to the first exemplary embodiment. The heat-sensitive element 2 includes the connecting conductor , which is separated from both contacts 4 by a fusible insulator 1_1_, as shown in Fig. 17. In this embodiment, the connecting conductor 10 is a spring steel strip that is pre-sprung, with one end at one contact 4 and the second end at the second contact 4. The body 1, similarly to the first exemplary embodiment, is divided into three parts - the first part contains the contacts 4, the retaining clips 14, etc., the second part contains the connecting conductor 10 and the fusible insulator 1 1 and the third part is the lid of the extinguishing agent tank, as shown in Fig. 16. The connecting conductor 10 is located in the second part of the body 1 in the recess. The second part of the body 1 includes protrusions pushing from one side to the center of the connecting conductor 10 and from the other side to the edges of the connecting conductor 10 so that the second part of the body 1 presses on the bent spring steel strip of the connecting conductor 10 and presses it against the fusible insulator 1_1_, making the connecting conductor 10 pre-sprung, as shown in Fig. 16. Thus, both ends of the connecting conductor 10 tend to move downwards towards the contacts 4, but they are prevented from doing so by the fusible insulator 1_1_, and the central part of the connecting conductor , on the other hand, tends to move upwards, where it is, however, engaged by a part of the body 1.

[0159] Between both ends of the connecting conductor 10 strip and the contacts 4 there is a fusible insulator 1 1 . In the second exemplary embodiment, the fusible insulator 1 1 is paraffin because it has a melting point of around 80 °C - the fusible insulator 11 softens as the temperature increases. In the idle state of the electrical fuse (and thus in the fault-free state in the circuit), both ends of the connecting conductor 10 press on two places with the fusible insulator 11, which are also at the contact 4 at the connection of the first part of the body with the second part of the body In the event of a fault, when the ambient temperature (of the surrounding environment, the contact 4 itself, etc.) increases, the fusible insulator 11 softens and melts. The pre-sprung connecting conductor 10 bends with both ends of the strip towards the contacts 4 due to heat, softening, melting of the fusible insulator 1 1 and pre- sprunging. Thus, the conductive connection of the contacts 4 can take place even before the fusible insulator 1 1 has melted - the pre-sprung connecting conductor 10 presses through the softened fusible insulator 11 - at a temperature of approximately 70 °C in the second exemplary embodiment. The fusible insulator - when the temperature of the connected electrical fuse in the circuit increases - flows away to the first part of the body 1 and the second part of the body At a certain stage of melting of the fusible insulator 11 (or complete melting of the fusible insulator 1 1 ), the connecting conductor 10 contacts the contact 4, as shown in Fig. 18 and Fig. 19, and also the retaining clip 14 at both ends of the connecting conductor 10 to increase the connection area. This connects the contacts 4 with the connected grounding conductors 19 and with the neutral conductors 18, and when the electrical fuse is placed in the circuit with a residual current device, the circuit is subsequently disconnected. After disconnecting the circuit depending on the temperature, the extinguishing agent may also be discharged (by knocking out the lid or burning through the openable wall 5, depending on the conditions around the fuse). The fusible insulator 11 is attached to the above- mentioned ends of the connecting conductor 10 for easier assembly of the electrical fuse. Other features of the electric fuse (arrangement and shape of the body 1, which is shown in Fig. 15, the contacts 4, the retaining clips 14, the tank, etc.) are in the second exemplary embodiment implemented in the same way as in the first exemplary embodiment. The electrical fuse according to the second exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection into the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0160] In the third exemplary embodiment, shown in Fig. 27, the electrical fuse includes the carrier 3 with the extinguishing agent in the form of a tank and the inlet that includes the contact 4, the retaining clip 14 and the inlet opening 22 in the body 1 of the fuse. The heat-sensitive element 2 includes the thermal fuse 9 as a functional member. The thermal fuse 9 includes the conductive jacket in which the conductive sliding partition, the flexible element and the fusible insert are housed. The flexible element is located between the conductive sliding partition and the fusible insert. The flexible element maintains a certain distance between the sliding partition and the fusible insert. The position of the sliding partition depends on the condition of the fusible insert. The thermal fuse 9 works in the following way. The first wiring conductor is connected to the conductive jacket and the second wiring conductor is connected from the other side of the thermal fuse 9. The second wiring conductor in a fault-free state is in contact with the sliding partition, which is in contact with the conductive jacket. The second wiring conductor is isolated from the conductive jacket so that there is no direct contact with the conductive jacket, only through the sliding partition. The conductive connection between the first wiring conductor and the second wiring conductor is therefore made through the conductive jacket. In the event of a fault, the temperature increases and the fusible insert softens or melts, which releases the flexible element and moves the sliding partition. The sliding partition moves away from the second wiring conductor, which breaks the conductive connection and disconnects the circuit. In the third exemplary embodiment, the first wiring conductor and the second wiring conductor are phase conductors 20, as indicated, for example, in Fig. 27.

[0161] The body 1 of the electric fuse in the third exemplary embodiment has cylindrical shape with a base of a general oval and includes two opposite inlets for connecting wiring conductors, an opening for the thermal fuse 9 and the extinguishing agent tank. Each inlet for wiring conductor connection includes an inlet opening 22 for the wiring conductor and the storage cavity 23 where the contact 4, the retaining clip 14 and the thermal fuse 9 terminal are located. The contact 4 is in the form of a copper sheet metal. The spring steel retaining clip 14, which includes two flexible arms, similar to the retaining clip 14 in the first exemplary embodiment is fixed to the contact 4. The first arm is attached to the groove of the body 1 in the inlet. The second flexible arm of the retaining clip 14, which forms an angle of approximately 70° with the first arm, points towards the contact 4. When inserting the wiring conductor into the inlet, the second arm is pressed by the wiring conductor in the direction from the contact 4 to the first arm. The second arm thus exerts elastic force on the wiring conductor and presses it against the contact 4 and thus the thermal fuse 9 terminal.

[0162] The thermal fuse 9, the contacts 4 and the retaining clips 14 are attached in the body 1 of the electrical fuse by two lids located in the bases of the cylindrical body 1, wherein one lid also closes the discharge opening of the tank for discharging the extinguishing agent. The lid closing the tank includes the openable wall 5 at the discharge opening. The openable wall 5 includes a groove so that in the event of a fire, the lid in this opening is ruptured for discharging the extinguishing agent by the increasing pressure in the tank. In this embodiment, the entire lid is not released from the rest of the body 1 including the part that attaches the thermal fuse 9, the contact 4, etc. The part of the lid thinned by the groove ruptures when the pressure of the extinguishing agent increases, in this particular embodiment at approximately 4 bar, and thus the extinguishing agent is discharged. The extinguishing agent can also be released by burning through the lid or the body 1 on other part of the tank, if this burning through occurs before the lid ruptures by pressure.

[0163] The shape, length and width of the groove are chosen so that the extinguishing agent is released quickly enough in the event of a rupture - in this embodiment, the surface of the groove is approximately a quarter of the surface of the lid and the groove has two intersecting branches, i.e. it has the shape of the letter "X".

[0164] The body 1 is made of a non-conductive material of transparent polycarbonate to allow quick and easy inspection whether the tank includes the extinguishing agent by simply looking at the body 1 of the electrical fuse.

[0165] In the fault state of the circuit in which the electrical fuse can be connected, first the phase conductor 20 is disconnected, as described above, and then the extinguishing agent can be discharged to extinguish the fire (by rupturing the lid by pressure from the tank, burning through the lid, etc., depending on the situation).

[0166] In the first, second and third exemplary embodiments, the Novec® extinguishing agent is used, which is in a liquid state in the tank under storage conditions and in a gaseous state during extinguishing. This extinguishing agent has a low boiling point, approximately 49 °C (at atmospheric pressure), a low latent heat of vaporization of approximately 90 kJ / kg, and therefore a high rate of evaporation. The extinguishing agent can thus very quickly transform from liquid state to gaseous state to extinguish the fire. When the temperature rises during fire, the vapor pressure of the extinguishing agent in the tank increases very quickly. In the above embodiments, the lid of the body 1 is designed to rupture and release the extinguishing agent with a concentration in the range of 6-9% of the volume of the wiring box where the electrical fuse is located. The amount of extinguishing agent, or the size of the tank, is thus chosen with regard to the volume of the wiring box where the fuse is to be installed and with regard to this required concentration. During the release of the extinguishing agent, the extinguishing agent also often immediately leaks from the unsealed wiring box, so the amount of extinguishing agent in the exemplary embodiment corresponds to the concentration of 10% after release, to achieve that said value of 6-9% in practice.

[0167] In the said exemplary embodiments, the extinguishing can be carried out in the following way. In the event of a fault and fire in the circuit, the temperature increases and the pressure in the tank rises as the liquid state of the extinguishing agent changes to gaseous. At a certain value of pressure in the tank, for which the lid of the body 1 is designed (depending for example on the volume of the extinguishing agent, the volume of the extinguished space, etc.), the lid ruptures and discharges the extinguishing agent in the gaseous state, which extinguishes the fire in the wiring box. The activation of the heat-sensitive element 2 occurs before the release of the extinguishing agent, so that a situation does not arise where the extinguishing agent extinguishes the fire but the circuit (in which the fault that caused the fire occurred) remains energized.

[0168] The Novec® extinguishing agent is also harmless to health and gentle on electronics, so there is no damage to the electronic elements located in the extinguished area due to the extinguishing agent during the fire extinguishing, which also helps to reduce the overall damage in the event of fire. The extinguishing agent in gaseous form has a specific odor, which helps to indicate a fault in the circuit.

[0169] The fourth exemplary embodiment is shown in Fig. 7-1 1 . The heat-sensitive element 2 in the fourth exemplary embodiment includes the bimetallic element 8 in the form of a strip firmly and conductively connected to the first contact 4, which takes the form of a rectangular copper sheet metal, similar to the first exemplary embodiment, as shown in Fig. 8. A conductive copper strip with a surface 12 for contact with the bimetallic element 8 is attached to the second opposite contact 4, as can be seen in Fig. 8. When the temperature increases during a fault, the bimetallic element 8 bends and contacts the surface 12 for contact with the bimetallic element 8 on the second contact 4, as shown in Fig. 10 and Fig. 11 , and thus the conductive connection of these two contacts 4 occurs.

[0170] The body 1 of the electrical fuse in the fourth exemplary embodiment is cylindrical in shape and includes two inlets for wiring conductors, as can be seen in Fig. 7. Each inlet includes two inlet openings 22 for cylindrical wiring conductors, similarly to the first exemplary embodiment, and the storage cavity 23 in which the retaining clip 14 and the contact 4 are located.

[0171] In the fourth embodiment, the retaining clip 14 is a flexible sheet metal part with an L-shaped cross-section, as can be seen in Fig. 9, where the shorter arm and a part of the longer arm are fixed in the groove in the body 1 of the electrical fuse and a larger part of the flexible longer arm touches the contact 4, as shown in Fig. 7. When inserting the wiring conductor, the longer arm is first pushed away from the contact 4 and then presses the wiring conductor to the contact 4 with elastic force, similarly to the retaining clip 14 from the first exemplary embodiment.

[0172] The contact 4 is pressed against the wall of the storage cavity 23 by the retaining clip 14. In the fourth exemplary embodiment, the contacts 4 are separated from each other by the non- conductive plastic partition, which is a part of the body 1. The storage cavities 23 are partially connected at one end of both contacts 4, where the bimetallic element 8 and the surface 12 for contact with the bimetallic element 8 are located to conductively connect the contacts 4.

[0173] The body 1 also includes the extinguishing agent tank located between the storage cavities 23, as shown in Fig. 7. The tank in this embodiment occupies most of the volume of the cylindrical body 1 of the electrical fuse, unlike in the first exemplary embodiment. The openable wall 5 covering the discharge opening of the tank is a part of the base of the cylindrical body 1.

[0174] The other features of the electric fuse (extinguishing agent, etc.) are implemented in the fourth exemplary embodiment in the same way as in the first exemplary embodiment. The electrical fuse according to the fourth exemplary embodiment is intended for connecting the wiring conductors mentioned in the first exemplary embodiment. Connection into the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0175] In the fifth exemplary embodiment, shown in Fig. 20-23, the heat-sensitive element 2 includes the bimetallic element 8 as the main functional member and two terminals 13 - one terminal 13 is connected to the contact 4 in one storage cavity 23 and the second terminal 13 is connected to the contact 4 in the second storage cavity 23. This is a standard irreversible bimetallic temperature switch with two terminals 13 commonly available on the market, which can be seen, for example, in Fig. 21 and Fig. 22. The terminals 13 are conductive wires that are used to connect the temperature switch into the circuit. In the fifth exemplary embodiment, both terminals 13 make a conductive connection with the temperature switch and the contacts 4, to which the wiring conductors are connected after the installation of the electrical fuse.

[0176] The terminals 13 together with the wiring conductors are attached to the contact 4 by the retaining clips 14. The retaining clip 14 includes the base 15, the flexible first arm 16 and the flexible second arm 17 as shown in Fig. 23. The base 15, the first arm 16 and the second arm 17 are made of one piece of material. In the fifth exemplary embodiment, the retaining clip 14 is made by bending a spring steel sheet metal. The base 15 is used to attach the retaining clip 14 to the contact 4 and is located on the opposite side of the contact 4 from the wiring conductor and terminal 13 after the electrical fuse is installed in the circuit. The base 15 is also in contact with the body 1 of the electrical fuse. An approximately perpendicular arm extends from the base 1.5, from which the first arm 16 and the second arm 17 extend. The first arm 16 is J-shaped and is used to attach the wiring conductor. The shorter branch of the first arm 16 points to the contact 4 and, thanks to the connection with the base 15 and the flexibility of the material when inserting the wiring conductor into the storage cavity 23, presses this wiring conductor against the contact 4. The second arm 17 is used to attach the terminal 13 and to press the terminal 13 against the contact 4. The second arm 17 similarly includes two branches - a shorter branch designed to contact the terminal 13 and a longer branch connecting the shorter branch with other parts of the retaining clip 14. With the help of both arms, the terminal 13 and the wiring conductor are pressed against the common contact 4, which makes a connection between the bimetallic temperature switch and the wiring conductor. In the event of a fault, similarly to the fourth exemplary embodiment, the bimetallic switch is activated and the contacts 4 are connected to the wiring conductors via the terminals 13 by the bimetallic switch.

[0177] The body 1 of the electrical fuse includes an opening to accommodate the temperature switch, which includes two channels, each leading into one storage cavity 23 with contacts 4 to lead out the terminals 13 to the contacts 4, as shown in Fig. 21 . The opening for the temperature switch is located above the extinguishing agent tank.

[0178] The inlet opening 22 for the wiring conductor is cylindrical in shape. The inlet opening 22 is divided into two sections - a first section, which opens with one end thereof into the surrounding environment outside the fuse, and a second section, which opens with one end thereof into the storage cavity 23. When inserting the wiring conductor, the first wiring conductor passes through the first section and then through the second section. The first cylindrical section has a cylinder diameter larger than the second cylindrical section. Between the first section and the second section there is a chamfer for a smoother transition between these sections and for easier routing of the wiring conductor further into the inlet to the contact and the retaining clip 14 for fixing this wiring conductor, as can be seen in Fig. 21 . Both sections are coaxial. The first section at the interface with the surrounding environment includes a recess to facilitate the routing of the wiring conductor into the inlet opening 22. The second section has a diameter equal to the conductive part with a certain clearance for easier routing of the wiring conductor. The first section has a diameter equal to the entire diameter of the wiring conductor, including the non-conductive wire sheath with a certain clearance for easier routing. These diameters and lengths of the individual sections guide the user when inserting the wiring conductors into the electrical fuse how much of the insulation sheath of the wiring conductor needs to be removed and how much of the wiring conductor needs to be inserted into the body 1 of the electrical fuse for the most efficient connection of the wiring conductor.

[0179] The other features of the electric fuse (shape of the body 1, which can be seen in Fig. 20, the contacts 4, the tank, etc.) are implemented in the fifth exemplary embodiment in the same way as in the fourth exemplary embodiment. The electrical fuse according to the fifth exemplary embodiment is intended for connecting the wiring conductors mentioned in the first exemplary embodiment. Connection into the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0180] In the sixth exemplary embodiment, shown in Fig. 24-25, the heat-sensitive element 2 includes the bimetallic element 8 as the main functional member. The bimetallic element 8 here has the shape of a round disc with a square opening in the center of the circle for attachment to the body 1 of the fuse, similarly to the first exemplary embodiment, as can be seen in Fig. 24. The edges of the bimetallic element 8 circle are located above the contacts 4, as shown in Fig. 25. Unlike the first exemplary embodiment, this embodiment does not include the strip as the member 21 for permanent conductive connection. This bimetallic element 8 is made as a one-way bimetallic element 8 - after deformation, it does not return to its original position even when cooled. Thus, in the event of a fault, the bimetallic element 8 bends and its edges touch the contacts 4 in both storage cavities 23, thus conductively connecting the contacts 4^and thus also the wiring conductors. Thanks to the properties of the one-way bimetal, when the surroundings cool down (e.g. the fire is extinguished), the bimetallic element 8 does not return to its original position, but still connects the contacts 4 to keep the circuit disconnected and prevent further fault, without the need for another component such as member 21 for permanent conductive connection.

[0181] The other features of the electric fuse (arrangement and shape of the body 1, the contacts 4, the retaining clips 14, the tank, etc.) are in the sixth exemplary embodiment implemented in the same way as in the first exemplary embodiment. The electrical fuse according to the sixth exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0182] In the seventh exemplary embodiment, which can be seen in Fig. 12, the heat-sensitive element 2 includes the bimetallic element 8 in the form of a strip firmly and conductively connected to the first contact 4, which takes the form of a rectangular copper sheet metal. A conductive copper strip with the surface 12 for contact with the bimetallic element 8_is attached to the second opposite contact 4, as can be seen, for example, in Fig. 12. Similarly to the fourth exemplary embodiment, when the temperature increases during a fault, the bimetallic element 8 bends, and contacts the surface 12 for contact with the bimetallic element 8 on the second contact 4, and thus the conductive connection of these two contacts 4 occurs. Both contacts 4 here include two retaining clips 14 as shown in Fig. 12, wherein the contact 4 and the retaining clip 14 are made of a single piece of flexible material. The contact ^includes a rectangular opening through which, once installed in the circuit, the wiring conductor passes. This contact 4 opening is in the seventh exemplary embodiment made by cutting three sides of the rectangle of the desired opening into the contact 4 sheet metal. Subsequently, a part of the sheet metal inside this rectangle was bent into the desired shape and angle so that this part of the metal sheet could press the wiring conductor onto the contact 4. This part of the bent sheet metal is the retaining clip 14. When fixing the wiring conductor to the electrical fuse, the wiring conductor, as it passes through the opening in the contact 4 for the wiring conductor to pass through in the direction of the arrow shown in Fig. 12, presses on the retaining clip 14, which, due to its elasticity, presses the wiring conductor onto the contact 4. In this exemplary embodiment, the wiring conductors inserted into the opening in the contact 4 and attached by the retaining clip 14 form an angle of approximately 180° with the wiring conductors at the second contact 4.

[0183] The other features of the electric fuse (shape of the body 1, the extinguishing agent tank, etc.) are in the seventh exemplary embodiment implemented in the same way as in the fourth exemplary embodiment. The electrical fuse according to the seventh exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0184] The eighth exemplary embodiment, which can be seen in Fig. 13, is similar to the seventh exemplary embodiment - one contact 4 includes the bimetallic element 8 in the form of a strip firmly and conductively connected to the first contact 4 and the second contact 4 comprises the surface 12 for contact with the bimetallic element 8, wherein both contacts 4 include openings for the wiring conductors to pass through and the bent part of the sheet metal, which is the retaining clip 14. In the eighth exemplary embodiment, at one opening in the contact 4_for the wiring conductor to pass through, there are two opposing retaining clips 14 which have a bent connection with the contact 4 on two opposite sides of the rectangular opening and are bent to the same side of the contact 4, as can be seen in Fig. 13. The openings with the pair of retaining clips 14 are thus created in the sheet metal by making an "H" shaped cut and bending both resulting clips 14 to the same side. When the wiring conductor passes through the opening and between the free ends of the clips 14, these retaining clips 14 press against each other and clamp the conductor core between them. The other features of the electric fuse (the shape of the body 1, the extinguishing agent tank, etc.) are in the eighth exemplary embodiment implemented in the same way as in the fourth exemplary embodiment. The electrical fuse according to the eighth exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0185] The ninth exemplary embodiment, which can be seen in Fig. 14, is similar to the eighth exemplary embodiment - one contact 4 includes the bimetallic element 8 in the form of a strip firmly and conductively connected to the first contact 4 and the second contact 4 comprises the surface 12 for contact with the bimetallic element 8, wherein both contacts 4 include openings for the wiring conductors to pass through and the bent part of the sheet metal, which is the retaining clip 14. The opening in the contact 4 for the wiring conductor to pass through is in the shape of a circle and the retaining clip 14 has a conical shape as shown in Fig. 14. This shape of the retaining clips 14 allows for a firmer attachment of the wiring conductors and a larger surface area for the conductive connection of the contact 4 and the wiring conductor than the implementation of the retaining clips 14 in the eighth and seventh exemplary embodiments.

[0186] The other features of the electric fuse (the shape of the body 1, the extinguishing agent tank, etc.) are in the ninth exemplary embodiment implemented in the same way as in the fourth exemplary embodiment. The electrical fuse according to the ninth exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0187] In the tenth exemplary embodiment, shown in Fig. 28 to 31 , which is based on the first exemplary embodiment, the heat-sensitive element 2 includes the bimetallic element 8 in the form of a bimetallic spring, which can be seen in Fig. 30 and which is located in the second part of the body 1, similarly to the heat-sensitive element 2 in the first exemplary embodiment, above the storage cavities 23. The bimetallic element 8 is located in the opening in the second part of the body 1, which is larger in size than the bimetallic element 8 in the direction in which the spring expands when the temperature increases, as can be seen in Fig. 29. This dimension is such that that the bimetallic element 8 is allowed to stretch as required to connect the wiring conductors. In a fault-free state, the spring is of such a length that it does not contact the contacts 4_and the retaining clips 14 in both storage cavities 23, as shown in Fig. 29 and Fig. 30. Due to the increasing temperature in the fault state, the spring as the bimetallic element 8 extends until it expands in such a way that the contacts 4 are connected in both storage cavities 23, as shown in Fig. 31 . The contacts 4 from both storage cavities 23 in the tenth exemplary embodiment extend all the way to the opening in the second part of the body 1 in which the bimetallic element 8 is housed, so that the contact 4 does not contact the spring in the fault-free state. The activation temperature of the heat-sensitive element 2_here depends on the distance between the contact 4 and the edge of the spring in the fault-free state, spring stiffness, etc. Unlike the first exemplary embodiment, this embodiment does not include the strip as the member 21 for permanent conductive connection. This bimetallic element 8 is made as a one-way bimetallic element 8 - after deformation, it does not return to the original position thereof even when cooled, similarly to the bimetallic element in the sixth exemplary embodiment.

[0188] The other features of the electric fuse (the shape of the body 1, which can be seen in Fig. 28, the extinguishing agent tank, the contacts 4, the retaining clips 14, etc.) are in the tenth exemplary version implemented in the same way as in the first exemplary embodiment. The electrical fuse according to the tenth exemplary embodiment is intended for connecting wiring conductors such as those mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment.

[0189] In the eleventh exemplary embodiment, shown in Fig. 32 and 33, the heat-sensitive element 2 includes the bimetallic element 8 in the form of a strip, as shown in Fig. 33, of one-way bimetal, similarly to the bimetallic element 8 in the sixth exemplary embodiment. In contrast to the bimetallic element 8 in the sixth exemplary embodiment, the bimetallic element 8 in the eleventh exemplary embodiment bends slowly as the temperature rises - the bimetallic element 8 visibly bends for a longer period of time than the bimetallic element 8 in the sixth exemplary embodiment. In the sixth exemplary embodiment, the disc slowly stretches as the temperature rises, and at the desired moment it suddenly bends into a fault state, where it connects the contacts 4, while the strip in the eleventh exemplary embodiment bends slowly, and therefore there is no abrupt change in the shape as in the disc. In this exemplary embodiment the heat-sensitive element 2 is attached to the body 1 of the electrical fuse in the common cavity with all contacts 4 and retaining clips 14, as can be seen in Fig. 33.

[0190] The other features of the electric fuse (the extinguishing agent tank, the contacts 4, the retaining clips 14, etc.) are in the eleventh exemplary embodiment implemented in the same way as in the sixth exemplary embodiment. The electrical fuse according to the eleventh exemplary embodiment is intended for connecting the wiring conductors mentioned in the first exemplary embodiment. Connection to the circuit with the residual current circuit breaker is the same as in the first embodiment. The following alternative features can be used as alternatives to the corresponding features from any of the above-mentioned embodiments - for the sake of brevity, only features implemented differently than mentioned above are listed in the following, and the features taken from previous designs are not listed again.

[0191] Alternatively, the member 21 for permanent connection of the contacts 4 may be made of a different conductive material that remains in a deformed state after deformation, such as steel, aluminum, etc.

[0192] Alternatively, only the bimetallic element 8 from the first exemplary embodiment can connect the contacts 4, i.e. without the permanently deformable member 21 for permanent conductive connection.

[0193] Alternatively, the retaining clip 14 in the first exemplary embodiment may include a third arm - the base - to attach the retaining clip 14 to the contact ^similarly to the fifth exemplary embodiment shown in Fig. 23, for example without the second arm 17 to attach the terminal 3.

[0194] Alternatively, the retaining clip 14 can be implemented as a standard Wago clamp. For easier access to the Wago clamp lever, which the user lifts and snaps down to attach the wiring conductor, and thus for easer attachment of the wiring conductor, the Wago clamp lever can be accessible from the side wall 6 of the body 1 of the electrical fuse - i.e. at least part of the Wago clamp lever thus protrudes from the side wall 6 of the body 1, as can be seen in Fig. 26. Thanks to the retaining clip 14 implemented in this way, it is possible to attach wiring conductors of different diameters (or different diameters of wiring conductor bundles) to one electrical fuse.

[0195] Alternatively, in all exemplary embodiments, the contact 4 can be made of a different conductive material, such as aluminum, or the contact can be plated.

[0196] Alternatively, the contact 4 can include multiple surfaces for contact with the wiring conductor, which are partially separated and at the same time conductively connected for one type of conductor, so that when the temperature in the circuit rises, the interruption occurs in all connected parts of the circuit.

[0197] Alternatively, the body 1 can be of transparent polystyrene, PMMA, PET, SAN, etc.

[0198] Alternatively, gaseous extinguishing agent, solid extinguishing agent or other liquid extinguishing agent may be used.

[0199] Alternatively, the fusible insert of the thermal fuse 9 may be made of a material selected from a group containing: polydecamethylene sebacate (with a degradation temperature of approximately 80 °C), polydecamethylene adipate (with a degradation temperature of approximately 80 °C), chloroprene rubber (with a degradation temperature of approximately 80 °C), poly-1 -dodecane (with a degradation temperature of approximately 76 °C), polyethylene sebacate (with a degradation temperature of approximately 76 °C), polyvinyl-n-propyl ether (with a degradation temperature of approximately 76 °C).

[0200] Alternatively, according to the second exemplary embodiment of the electrical fuse solution, the connecting conductor 10 can be connected to one contact 4 even in a fault-free state of the circuit (e.g. by welding), while it is separated from the second contact 4 by the fusible insulator 11 . Similarly, in the first exemplary embodiment, the member 21 for permanent conductive connection can be connected to one contact 4 even in the fault-free state of the circuit, while it is separated from the second contact 4 in the fault-free state.

[0201] Alternatively, the carrier 3 with the extinguishing agent can take the form of a solid porous structure located on the body 1 of the electrical fuse (e.g. by gluing). Heat (or the fire directly) can lead to the release of the gaseous extinguishing agent from the solid porous structure. The solid structure of the carrier 3 can be glued to the inlet side of the body 1 as shown in Fig. 26.

[0202] This solid structure of the carrier 3 is preferably made of plastic with a high burning temperature.

[0203] Alternatively, the body 1 may include a recess on the outside in which the solid structure with the extinguishing agent may be located. The solid porous carrier 3 with the extinguishing agent can therefore be glued into this recess to prevent easy removal of the carrier 3 from the body 1 of the electrical fuse. Alternatively, the solid structure of the carrier 3 can be attached to the body 1 in other ways. Alternatively, the solid structure of the carrier 3 can be directly a part of the body 1 of the electrical fuse.

[0204] An alternative exemplary embodiment of the retaining clip 14 includes the first arm 16 for attaching the wiring conductor and the second arm 17 for attaching the terminal 13 of the heatsensitive element 2 so that the terminal 13 is pressed against the wiring conductor. This alternative embodiment of the retaining clip 14 may be a part of the alternative embodiment of the electrical fuse including the other features of the fifth exemplary embodiment (the heat-sensitive element 2, the body 1, the extinguishing agent tank, etc.) except for the contacts 4 - the terminal and the wiring conductor are pressed together (they are thus conductively directly connected) and not to the contact 4.

[0205] Alternatively, any inlet opening 22 for wiring conductor in any embodiment may include two cylindrical sections, wherein the first section has a larger diameter than the second section. The first section connects the surrounding environment with the inside of the body 1 of the electrical fuse and the second section connects the first section with the storage cavity 23 in the body 1 of the electrical fuse. Alternatively, the inlet opening 22 can be pyramidal or otherwise shaped.

[0206] Alternatively, the spring as the bimetallic element 8 in the electrical fuse according to the tenth exemplary embodiment is attached to the at least one contact 4 from one storage cavity 23, while it is separated from all contacts 4 from the second storage cavity 23 in a fault-free state. When the temperature increases, the spring is extended only on one side of the spring towards the contact 4 from the second storage cavity 23.

[0207] The electrical fuse can be a part of the wiring system.

[0208] The twelfth exemplary embodiment is a wiring system including the electrical fuse according to the first exemplary embodiment. The wiring system also includes a socket, an electrical back box located in the wall, a phase conductor 20, a neutral conductor 8, a grounding conductor 9, a distribution box with a residual current device, an appliance connected to a socket, etc. The electrical fuse is located in the electrical back box, where various faults most often occur, around the perimeter of the electrical back box. One grounding conductor 19 is attached to the body 1 at one side wall 6 of the electrical fuse as the inlet conductor routed from the grounding terminal and three grounding conductors 19 as the outlet conductors routed from the electrical fuse to the socket. Two neutral conductors 18 are attached to the body 1 at the second side wall 6 as inlet conductors routed from the terminal block and two neutral conductors 18 as the outlet conductors routed from the electrical fuse to the socket. In the event of a fault in the wiring system, when the temperature rises, the electrical fuse conductively connects the connected grounding conductors 19 and neutral conductors 18, which leads to the leakage of at least part of the current, which activates the residual current circuit breaker, which disconnects the circuit.

[0209] If, in a fault state, the member 21 for permanent conductive connection contacts the contacts 4 and the retaining clips 14, i.e. for example it does not contact only the contacts 4 themselves, the conductivity is increased, and therefore the residual current device more easily captures this leakage current and breaks the circuit.

[0210] Alternatively, the wiring system described above (twelfth exemplary embodiment) may include the electrical fuse from other exemplary embodiments, which include as the main functional member of the heat-sensitive element 2 the bimetallic element 8 or the connecting conductor 10 with the fusible insulator 1 1 .

[0211] The thirteenth exemplary embodiment is a wiring system including the electronic fuse according to the third exemplary embodiment. The wiring system also includes a socket, an electrical back box located in the wall, a phase conductor 20, a neutral conductor 18, a grounding conductor 1.9, a distribution box, an appliance connected to a socket, etc. The electrical fuse is located in the electrical back box, where various faults most often occur. To one base of the body, the phase conductor 20 is connected as the inlet conductor routed from the distribution box and to the second base, the phase conductor 20 is connected as the outlet conductor routed from the electrical fuse to the socket. Both phase conductors 20 are conductively connected using the electronic fuse. In the event of a fault in the wiring system, when the temperature rises, the electrical fuse disconnects the phase conductors 20 and the current flow in the circuit is interrupted.

[0212] Industrial Applicability The electrical fuse can be installed as part of the house electrical installation, distribution boxes, vehicle electrical wiring, etc.

[0213] List of Reference Signs

[0214] 1 - Body

[0215] 2 - Heat-sensitive element

[0216] 3 - Carrier

[0217] 4 - Contact

[0218] 5 - Openable wall

[0219] 6 - Side wall

[0220] 7 - Edge

[0221] 8 - Bimetallic element

[0222] 9 - Thermal fuse

[0223] 10 - Connecting conductor

[0224] 11 - Fusible insulator

[0225] 12 - Surface for contact with the bimetallic element

[0226] 13 - Outlet

[0227] 14 - Retaining clip

[0228] 15 - Base

[0229] 16 - First arm of the retaining clip

[0230] 17 - Second arm of the retaining clip

[0231] 18 - Neutral conductor

[0232] 19 - Grounding conductor

[0233] 20 - Phase conductor

[0234] 21 - Member for permanent conductive connection

[0235] 22 - Inlet opening

[0236] 23 - Storage cavity

Claims

CLAIMS1. An electrical fuse comprising a body (1 ), two inlets for connecting wiring conductors and a heat-sensitive element (2) for conductive connection of the wiring conductors depending on temperature, wherein all inlets and the heat-sensitive element (2) are located in the body (1 ), characterized in that the body (1 ) comprises a carrier (3) with an extinguishing agent.

2. The electrical fuse according to the claim 1 characterized in that the carrier (3) with the extinguishing agent is located between the inlets.

3. The electrical fuse according to the claim 1 or 2 characterized in that the carrier (3) is an extinguishing agent tank, wherein the extinguishing agent tank is a part of the body (1 ).

4. The electrical fuse according to the claim 3 characterized in that the extinguishing agent tank has a discharge opening, wherein the discharge opening is directed in a different direction than the location of the heat-sensitive element (2).

5. The electrical fuse according to any of the claims 3 or 4 characterized in that the extinguishing agent tank comprises an openable wall (5) for discharging the extinguishing agent when pressure and / or heat is applied to this openable wall (5).

6. The electrical fuse according to the claim 5 characterized in that the openable wall (5) is made of a material with a melting temperature lower than that of the rest of the body (1 ).

7. The electrical fuse according to the claim 5 or 6 characterized in that the openable wall (5) comprises at least one area with a weakening for rupture of the extinguishing agent tank under pressure and / or heat.

8. The electrical fuse according to any of the foregoing claims characterized in that the extinguishing agent has a temperature for transformation into the gaseous state in the range from (-20) to 90 °C.

9. The electrical fuse according to any of the foregoing claims characterized in that the body (1 ) comprises two side walls (6) connected by a common edge (7), wherein the edge (7) is rounded or chamfered to fit into a wiring box, wherein each inlet includes a surface for contact with the wiring conductor, wherein the surface for contact with the wiring conductor at the first inlet is non-parallel to the surface for contact with the wiring conductor at the second inlet, wherein the surface for contact with the wiring conductor at the first inlet andthe surface for contact with the wiring conductor at the second inlet converge towards the rounded or chamfered edge (7) of the body (1 ).

10. The electrical fuse according to any of the foregoing claims characterized in that the heatsensitive element (2) is a temperature switch.11 . The electrical fuse according to any of the foregoing claims characterized in that the heatsensitive element (2) includes a functional member selected from a group comprising a bimetallic element (8); a thermal fuse (9); and a connecting conductor (10) with a fusible insulator (1 1 ) for isolating the connecting conductor (10) from at least one wiring conductor.

12. The electrical fuse according to any of the foregoing claims characterized in that each inlet includes at least one electrical contact (4) for conductive connection of the at least one wiring conductor.

13. The electrical fuse according to the claim 1 1 characterized in that the heat-sensitive element (2) includes the bimetallic element (8) for connecting the wiring conductors when the temperature increases.

14. The electrical fuse according to the claim 13 characterized in that each inlet comprises at least one electrical contact (4) for conductive connection of at least one wiring conductor, wherein the bimetallic element (8) is firmly and conductively connected to the first contact (4), wherein the second contact (4) comprises a surface (12) for abutment with the bimetallic element (8) for connection with the first contact (4).

15. The electrical fuse according to the claim 13 characterized in that each inlet comprises at least one electrical contact (4) for conductive connection of at least one wiring conductor, wherein the heat-sensitive element (2) comprises two terminals (13), wherein each terminal (13) is conductively connected to one of the contacts (4), wherein the terminals (13) are connectable by the bimetallic element (8).

16. The electrical fuse according to the claim 13 characterized in that the heat-sensitive element (2) comprises two terminals (13), wherein each terminal (13) is connected to one of the inlets, wherein the terminals (13) are connectable by the bimetallic element (8), wherein at least one inlet comprises a retaining clip (14) that includes a base (15), a flexible first arm (16) to press at least one wiring conductor to the base (15) and a flexible second arm (17) to press the corresponding terminal (13) to the base (15).

17. The electrical fuse according to the claim 16 characterized in that the retaining clip (14) is made of a single piece of sheet metal.

18. The electrical fuse according to any of the claims 13 to 17 characterized in that the heatsensitive element (2) comprises a permanently deformable member (21 ) for permanent conductive connection of wiring conductors after thermal deformation of the bimetallic element (8), wherein the member (21 ) for permanent conductive connection has a lower modulus of elasticity than the bimetallic element (8).

19. The electrical fuse according to the claim 1 1 characterized in that the heat-sensitive element (2) comprises the connecting conductor (10) with the fusible insulator (11 ) to isolate the connecting conductor (10) from at least one wiring conductor, wherein the heatsensitive element (2) comprises a pre- sprung element to press a part of the connecting conductor (10) to the fusible insulator (1 1 ).

20. The electrical fuse according to the claim 19 characterized in that each inlet comprises at least one electrical contact (4) for conductive connection of at least one wiring conductor, wherein the fusible insulator (1 1 ) is between at least one of the contacts (4) and the pressed part of the connecting conductor (10).21 . The electrical fuse according to any of the claims 19 or 20 characterized in that the fusible insulator (11 ) has a melting point in the range from 50 to 90 °C.

22. The electrical fuse according to any of the claims 19 or 21 characterized in that the presprung element is a part of the connecting conductor (10).

23. The electrical fuse according to the claim 1 1 characterized in that the heat-sensitive element (2) comprises the thermal fuse (9).

24. The electrical fuse according to the claim 23 characterized in that at least one inlet comprises a retaining clip (14) to press the thermal fuse (9) terminal to the wiring conductor.

25. A wiring system comprising a wiring box and wiring conductors, characterized in that it comprises the electrical fuse according to any of the foregoing claims placed in the wiring box, wherein the first wiring conductor is routed to one inlet and the second wiring conductor is routed to the second inlet.

26. The wiring system according to the claim 25 characterized in that the carrier (3) comprises an amount of extinguishing agent for filling the wiring box with a concentration of at least 4 %.

27. The wiring system according to the claim 25 or 26 characterized in that the first wiring conductor is neutral conductor (18) and the second wiring conductor is grounding conductor (19), wherein the system comprises a residual current device.