Fuse device for high voltage applications

Abstract

The present invention relates to a fuse device for high-voltage applications, comprising a housing (10), an actuation chamber (12) and an arc-extinguishing chamber (14) formed within the housing (10), a busbar (16) extending through the housing (10) and between the actuation chamber (12) and the arc-extinguishing chamber (14), and a separation element (34) that moves out of the actuation chamber (12) and against the busbar (16) by means of an actuator (32), wherein a section (42) of the busbar can be moved to the arc-extinguishing chamber (14). In this invention, the busbar (16) is cut at a first predetermined break point (74); and a guide element (48) extends into the arc-extinguishing chamber (14) and has two opposing sidewalls (52, 54) that extend to a support surface (102) that defines the arc-extinguishing chamber (14) along the direction of movement of the separating element (34), and when viewed along the direction of movement of the separating element (34), the two sidewalls extend past opposing longitudinal sides (55) of the busbar segment (42) to be separated. The object of the invention is to extinguish the arc more quickly by squeezing the arc in a gapless manner in the triggered state. This is achieved by providing stiffeners (111) on the two sidewalls (52, 54) that extend along the direction of movement of the separating element (34) and at least along the length of the sidewalls (52, 54) to a support surface (102) that defines an arc-extinguishing chamber (14) along the direction of movement of the separating element (34) and abuts against the support surface when the separating element (34) moves into the arc-extinguishing chamber (14).

Description

[0001] This invention relates to a fuse device for high-voltage applications, comprising a housing; an actuation chamber and an arc-extinguishing chamber formed within the housing; a busbar extending through the housing and between the actuation chamber and the arc-extinguishing chamber; a separating element movable from the actuation chamber by means of an actuator and moving against the busbar, by means of which a section of the busbar can be moved into the arc-extinguishing chamber to cut the busbar at a first predetermined break point; and a guiding element extending into the arc-extinguishing chamber and having at least two opposing sidewalls extending to define a support surface of the arc-extinguishing chamber along the direction of movement of the separating element.

[0002] This type of fuse device is typically implemented as an actuator with a pyrotechnic igniter, particularly used in motor vehicles with high-voltage applications (such as hybrid or fully electric vehicles) to disconnect the power line between the battery and electrical equipment (most importantly, the vehicle's drive system) within a fraction of a second in the event of an accident, thus preventing a short circuit. Furthermore, the disconnecting element must be guided as precisely as possible within the housing to ensure reliable disconnection.

[0003] However, during busbar separation, high voltage can cause an electric arc between the free ends of the busbar. This means current continues to flow, and this can last for several seconds, resulting in extremely high short-circuit currents, which could potentially cause life-threatening electric shocks to vehicle occupants or rescue personnel. Since these arcing effects cannot be completely avoided, measures must be taken to neutralize them as quickly as possible. Furthermore, the separation element must be guided as precisely as possible within the housing to ensure reliable separation.

[0004] For example, WO 2021 / 240104 A1 discloses a pyrotechnic safety device whose housing includes a guide section into which a separating piston moves after being triggered by an igniter, wherein the guide section has an surrounding wall along which the separating piston moves.

[0005] Furthermore, US 11,081,303 B2 describes a pyrotechnic fuse device in which a rubber ring is provided at the base of the arc-extinguishing chamber, designed to convert the kinetic energy of the separating element into deformation energy. Upon triggering, the separated bus section is located between the separating element and the rubber ring, and the resulting arc can spread on both sides of the piston within the housing. This arrangement does not guarantee that the arc will be reliably and quickly extinguished; therefore, the housing design incorporates multiple air-blowing channels.

[0006] Therefore, the proposed task is to invent a fuse device for high-voltage applications that, when triggered, can both stretch the arc to extinguish it more quickly and reliably mechanically disconnect it to ensure that the arc is extinguished completely as quickly as possible, thereby preventing the generation of short-circuit currents that could lead to electric shock.

[0007] This task is accomplished by a fuse device for high-voltage applications having the features described in claim 1.

[0008] The safety device for high-voltage applications according to the invention has a housing in which an actuation chamber and an arc-extinguishing chamber are formed. The housing can, in particular, be constructed as a multi-part structure and, for example, may have at least one second housing portion surrounding the arc-extinguishing chamber and one first housing portion surrounding the actuation chamber. The term actuation chamber is understood as a space in which an actuator is at least partially disposed. This actuator can, in particular, be a pyrotechnic igniter that generates pressure upon triggering, thereby pushing a separating element out of the actuation chamber. The term arc-extinguishing chamber is understood as a space into which a busbar segment is moved, thereby separating the busbar into at least two parts. Due to the presence of high voltage, an electric arc—also called plasma—is formed between the separated busbar segments within the arc-extinguishing chamber, which leads to ablation. To minimize the duration of the arc, it must be extinguished as quickly as possible. The fuse device also includes a busbar that passes through the housing and extends between the actuation chamber and the arc-extinguishing chamber. Furthermore, in the non-triggered state of the fuse device, the separating element is arranged in the actuation chamber. This separating element can move against the busbar by an actuator, and when the actuator is triggered, the separating element separates the busbar section to cut the busbar at a predetermined break point and moves it into the arc-extinguishing chamber, thus itself also moves at least partially from the actuation chamber into the arc-extinguishing chamber.

[0009] Furthermore, the fuse device has a guiding element that extends into the arc-extinguishing chamber and has at least two opposing sidewalls that extend to define a support surface of the arc-extinguishing chamber along the direction of movement of the separating element. Thus, these sidewalls have an extension component pointing from the busbar segment to be separated towards the arc-extinguishing chamber, and an extension component extending parallel to the longitudinal side of the busbar segment to be separated. However, this does not mean that the sidewalls must be straight. Instead, the sidewalls can, for example, form two opposing portions of a hollow cylinder. Most importantly, when extending from the actuation chamber toward the busbar, these sidewalls are arranged beside the busbar segment to be separated and at least surround the separating element. In other words, viewed along the direction of movement of the separating element, the sidewalls extend opposite to the longitudinal side of the busbar segment to be separated and the side surface of the separating element. The separating element is guided by the guiding section and moves along the sidewalls during its movement, thereby preventing tilting. The guiding section can extend, specifically from the actuation chamber, at least from the area of ​​the actuation chamber closest to the busbar, and at least from the area surrounding the longitudinal side of the busbar segment to be separated, to the end of the arc-extinguishing chamber, such that the separating element is guided within the guiding section throughout its entire stroke. The guiding section can also extend only from the side of the busbar segment closest to the arc-extinguishing chamber. The two sidewalls can also be constructed as continuous walls. Importantly, these segmented walls are not parallel to the first predetermined break point, but rather guide the separating element along the main extension direction of the busbar. Thus, in a top view of the busbar, the sidewalls are formed opposite to the free side surface of the busbar, starting from the actuation chamber. However, opposite does not mean they must be arranged parallel. Therefore, the sidewalls can also form part of a circle, or can be set at an angle to the longitudinal side. This depends on the shape of the separating element in order to provide guidance for it.

[0010] According to the invention, stiffeners are formed on two sidewalls extending along the direction of movement of the separating element and extending at least along the length of the sidewalls to a support surface that defines an arc-extinguishing chamber along the direction of movement of the separating element, and the separating element abuts against the support surface when it moves into the arc-extinguishing chamber. Thus, these stiffeners, extending from the busbar to the support surface, reliably seal any gaps that may exist between the sidewalls of the guide section and the separating element, ensuring completely gap-free guidance of the separating element. In this way, once the separating element abuts against the support surface, the stiffeners completely isolate the space toward the first predetermined break point from the space into which the busbar section to be separated is twisted. Since there is no longer a continuous free space available between the two free ends of the separated busbar section and the fixed busbar section, the arc is thus extinguished by compression. Therefore, further flashover between these two ends is prevented, which prolongs the arc length during the movement of the separating element and rapidly extinguishes the arc upon contact with the separating element.

[0011] After the separating element has passed its travel range, the stiffener is preferably at least partially sheared off by the separating element. If the stiffener is made of a material with the same or lower hardness as the separating element, this shearing occurs during movement. Thus, this gapless state is ensured throughout the entire travel range, and therefore throughout the entire movement of the separating element, where the travel range is understood as the area traversed by the separating element inside the arc-extinguishing chamber.

[0012] Alternatively or additionally, after the separating element has passed its travel range, the separating element is at least partially cut into by the stiffener. If the stiffener is made of a material harder than the separating element, the separating element is cleanly cut into as it passes through the stiffener. If the stiffener and the separating element have similar hardness, the separating element is partially cut into while the stiffener is partially sheared off. In all cases, gapless guidance and complete sealing isolation of the space where the fixed busbar section and the separating busbar section are arranged are guaranteed.

[0013] In a particularly preferred embodiment, after the separating element has passed its travel range, the support surface for the separating element is formed by a damping element disposed on the base of the housing and located within the arc-extinguishing chamber, and the separating element abuts against this damping element after its travel range. When the separating element impacts the damping element, the damping element deforms to absorb the kinetic energy of the separating element and convert it into deformation energy. This deformation also generates a strong supporting force, thereby creating a strong seal between the separating element and the damping element that lasts for a relatively long time, effectively preventing arc flashover caused by gaps between the damping element and the separating element. Thus, reliable and complete arc interruption and extinguishing are achieved, while protecting the housing from excessive impact forces. This means the housing can be made thinner, thus saving material and space.

[0014] After the separating element has passed its travel range, the separating element, stiffener, and damping element completely isolate the space where the separated busbar segment is located from the space where the free end of the fixed busbar segment forming the first predetermined break point is located. This prevents arcing between the two free ends of the busbar. In this state, the separated busbar segment is therefore located on the side of the separating piston and damping element opposite to the first predetermined break point. Therefore, the arc generated between the predetermined break point on the fixed busbar segment and the predetermined break point on the separated busbar segment initially extends axially between the damping element and the separating element until the separating element impacts the damping element. During this stage, the busbar segment to be separated rotates toward the side of the separating element away from the area of ​​the fixed busbar segment adjacent to the first predetermined break point. Once the separating element impacts the damping element, the arc is extinguished because there is no longer any continuous free space between the two free ends of the separated busbar segment and the fixed busbar segment.

[0015] The damping element is preferably fixed to the base by at least two sidewalls of the guide section. This prevents the damping element from sliding on the base without the need for additional components, thus avoiding gaps between the separating element and the damping element caused by suboptimal positioning of the damping element relative to the separating element or the guide section.

[0016] In another embodiment, the damping element is made of an elastomer, which allows for a high degree of deformation, thereby converting a large amount of kinetic energy into deformation energy. This effectively reduces the mechanical load on the enclosed housing. Furthermore, since the deformation capacity ensures that the separating element rests flat against the damping element for at least a period of time, gap formation is reliably prevented when the arc is extinguished, thus allowing for greater tolerances for manufacturing inaccuracies.

[0017] It is also advantageous if the damping element includes deformable structures that abut against the base of the arc-extinguishing chamber. These deformable structures are particularly effective in converting kinetic energy into deformation energy and ensure a smoother deceleration of the separating element. Because the deformable structures are supported on the base, the support surface of the damping element can still be easily designed to correspond to the opposing separating surface of the separating element, despite the introduction of these structures.

[0018] In a particularly preferred embodiment of the invention, the separating element has a first separating edge that, when viewed along the direction of movement of the separating element in the untriggered state, is at its minimum distance from the busbar segment to be separated. The shape of the portion of this separating edge that is at its minimum distance from the first predetermined break point in the main extension direction of the busbar is complementary to the surface region of the damping element, which is arranged opposite to said portion of the separating edge along the direction of movement of the separating element. This ensures that the separating edge of the separating element reaches the damping element flatly, thereby closing the gap across the entire width between the separating element and the damping element, and thus simultaneously closing the gap across the entire width of the arc and the busbar. In this way, a sealed contact is achieved across the entire width over which the arc may spread, thereby effectively cutting off the arc.

[0019] In a further advantageous improvement of this embodiment, a sealing lip is formed on the support surface of the damping element at a location adjacent to a surface region having a complementary shape. This sealing lip is positioned at a minimum distance from the separating element when viewed along the direction of movement of the separating element before the fuse is triggered. This sealing lip enhances the sealing effect in a known manner upon impact with the separating surface. The line contact at the moment the arc breaks generates a strong separating force.

[0020] The sealing lip preferably extends across the entire width of the arc-extinguishing chamber to the stiffening plates defining the sidewalls of the chamber, thereby ensuring separation across the entire usable width of the arc. Thus, the stiffening plates of the damping element, combined with the stiffening plates on the sidewalls, form a seal on three sides.

[0021] In an advantageous embodiment, the space defined by the separating element, in which the predetermined break point of the fixed busbar section is located, is fluidly connected to the metal mesh. Since this space is further isolated by damping elements, separating elements, and sidewalls, gas can only escape through the metal mesh. Therefore, the electric arc must enter the metal mesh, causing the mesh to vaporize and absorb some of its energy. This helps to extinguish the arc more quickly.

[0022] Particularly preferred is that the guide section has a third sidewall that connects the two opposing sidewalls to each other and extends parallel to the first predetermined break point into the arc-extinguishing chamber. After completing its travel range, the side surface of the separating element facing the first predetermined break point is arranged opposite to the third sidewall. This forms a three-sided guide for the separating element, which also helps to prevent tilting in the longitudinal direction.

[0023] Particularly advantageous is that the metal mesh is positioned on the side of the third sidewall opposite the separating element, and this metal mesh is fluidly connected through an opening in the third sidewall to the space where the free end of the fixed busbar segment forming the first predetermined break point is arranged. Therefore, the electric arc must pass through the metal mesh; otherwise, there would be no space for it to expand. Nevertheless, the three-sided guidance is maintained, and the position of the metal mesh can also be defined by the third sidewall.

[0024] The housing is preferably constructed in three parts: a first housing part radially surrounds the actuation chamber; a second housing part radially surrounds the arc-extinguishing chamber and forms the base of the arc-extinguishing chamber, on which the damping element is disposed; and a third housing part surrounds the busbar and is disposed between the first and second housing parts by a flange section, from which a guide section with sidewalls extends. By connecting the housing parts to each other, the damping element is also attached to the base of the second housing part in one step, and the second and third housing parts form a double-walled outer shell of the arc-extinguishing chamber. Furthermore, there is no need to construct an additional component as the guide section, as it serves simultaneously for fixing the busbar and calibrating the separation element.

[0025] Further advantageously, the distance from the separating surface of the separating element to the busbar increases from the first separating edge toward the opposite second end in the untriggered state. This ensures that, upon triggering, the busbar segment to be separated is first purely twisted into the arc-extinguishing chamber, which allows the arc to be extinguished by pressing the arc against one side of the busbar segment to be separated.

[0026] In a further improvement to this embodiment, the busbar has a second predetermined break point. The busbar segment to be separated, after being cut at the first predetermined break point, can twist around this second predetermined break point. A cavity is formed in the space between the damping element and the sidewall of the second housing portion defining the arc-extinguishing chamber. The busbar segment to be separated, after being cut, is placed in this cavity and located next to the separating element. Therefore, this cavity forms the fourth side surface of the arc-extinguishing chamber. Upon triggering, the busbar segment to be separated is twisted into the cavity and collected upright therein. During this process, further separation occurs at the second predetermined break point, causing the busbar segment to be broken on both sides, thus loosely accommodated in the cavity. This cavity is separated from the space where the first predetermined break point of the fixed busbar segment is arranged by ribs and a separating piston.

[0027] Therefore, a fuse device for high-voltage applications has been invented, in which the arc generated during busbar segment separation is extinguished very quickly by significant stretching and subsequently by complete spatial isolation of the separated busbar segment from the fixed busbar segment adjacent to the predetermined break point. This avoids prolonged short circuits and electric shocks, as well as subsequent injuries to personnel. However, this fuse device can still have a relatively small structure and thin wall thickness because the kinetic energy of the separating element is absorbed by the damping element. Therefore, the stiffeners on the sidewalls defining the boundaries and the damping element act as sealing elements for the gap between the separating element and the sidewalls and the base of the housing.

[0028] The accompanying drawings illustrate an exemplary embodiment of a fuse device for high-voltage applications according to the present invention, and will be described below with reference to a fuse device designed as a pyrotechnic circuit breaker. The terms “axial” and “radial” as used below refer to the movement of the separating element of the fuse device: the axial direction corresponds to the direction of movement of the separating element, while the radial direction constitutes a component perpendicular to the direction of movement.

[0029] Figure 1 A cross-sectional side view of the fuse device according to the invention before actuation is shown.

[0030] Figure 2 It shows Figure 1 A cross-sectional side view of the fuse device according to the present invention after actuation.

[0031] Figure 3 It shows Figure 1 A cross-sectional side view of the fuse device according to the present invention rotated 90° before actuation.

[0032] Figure 4 A top-view cross-section of the arc-extinguishing chamber of the fuse device is shown.

[0033] The fuse device according to the invention shown in the attached figure is designed as a pyrotechnic circuit breaker, consisting of a housing 10, inside which an actuation chamber 12 and an arc-extinguishing chamber 14 are formed, which are separated from each other by a busbar 16 extending through the housing 10, the busbar being used, for example, to connect a motor vehicle battery to an electrical device such as a drive motor.

[0034] The housing 10 is designed as a double-wall structure, wherein the inner wall 18 at least partially radially defines the arc-extinguishing chamber 14 and the actuation chamber 12, and the outer wall 20 is radially arranged at a certain distance from the inner wall 18 and externally defines the fuse device.

[0035] The housing 10 is generally constructed in three parts, wherein the third housing part 26 is clamped and fixed between the first housing part 22 (in which the actuation chamber 12 is centrally formed) and the second housing part 24 (in which the arc extinguishing chamber 14 is formed), and a sealing ring 28 is inserted between them.

[0036] The actuation chamber 12 in the first housing portion 22 is radially surrounded by the inner wall 30 of the first housing portion 22. Inside this actuation chamber 12, in a region away from the arc-extinguishing chamber 14, an actuator 32, designed as a pyrotechnic igniter, is arranged. Furthermore, in the untriggered state, a piston-shaped separation element 34 is movably arranged inside the actuation chamber 12 and is radially guided at least segmentally by the inner wall 30 of the first housing portion 22, defining the actuation chamber 12 axially toward the actuator 32. The first housing portion 22 also has an outer wall 36, which is connected to the inner wall 30 by ribs (not shown). Between the inner wall 30 and the outer wall 36, a decompression volume 38 is formed by the free space between the ribs.

[0037] The third housing portion 26 includes a flange section 40 through which it is clamped and secured between the first housing portion 22 and the second housing portion 24. The flange section 40 surrounds the busbar 16 on all sides except for the busbar section 42 to be separated, which is axially adjacent to the actuation chamber 12 and the arc-extinguishing chamber 14 before triggering. The busbar section 42 is bounded only by the third housing portion 26 on its radial side, while the two sides of the busbar section 42 adjacent to the actuation chamber 12 and the arc-extinguishing chamber 14 are exposed to them. Two or more flow passages 43 are also formed in the flange section 40, arranged axially on the decompression volume 38 of the first housing portion 22. Starting from the flange section 40, the axially extending guide section 44 engages in the seat 46 on the inner wall 30 of the first housing section 22 in the region of the first housing section 22 facing the third housing section 26, and radially defines the actuation chamber 12 in this region, thereby also guiding the separation element 34.

[0038] The third housing portion 26 also includes a guide section 48 extending into the second housing portion 24 and having three sidewalls 50, 52, and 54 that define the arc-extinguishing chamber 14 from three sides. The third sidewall 50 extends approximately parallel to the first predetermined break point and is therefore perpendicular to the main extension direction of the busbar 16, while the two opposing sidewalls 52 and 54 are arranged opposite to the longitudinal sidewalls 55 of the busbar segment to be separated. The guide element 48 is open on a fourth sidewall 57. On this sidewall, the sidewall 56 of the arc-extinguishing chamber 14 is formed by the inner wall 58 of the second housing portion 24. Fin-shaped stop ribs 60 are formed on this inner wall 58, protruding into the arc-extinguishing chamber 14.

[0039] The three sidewalls 50, 52, and 54 of the guide element 48, extending toward the base 62 of the second housing portion 24, are precisely fitted within wall segments 64 of the second housing portion 24, which extend from the base 62 toward the first housing portion 22. The sidewalls 50, 52, 54, wall segments 64, and the sidewall 56 of the second housing portion 24 are radially arranged at a distance from the surrounding outer wall 66 of the second housing portion 24, which radially positions the fuse assembly outward.

[0040] A damping element 68 is disposed on the base 62 and defines an arc-extinguishing chamber 14 axially from the base 62 of the second housing portion 24 and axially below the separating element 34. Furthermore, a metal mesh 70 is arranged on the base 62, immediately adjacent to the damping element 68, on the side of the arc-extinguishing chamber 14 opposite to the stop rib 60. This metal mesh extends axially between the sidewall 50 and the outer wall 66 surrounding the arc-extinguishing chamber 14. The metal mesh 70 extends axially until it approaches the flange section 40 of the third housing portion 26. An opening 72 is formed in the sidewall 50 of the guide section 48 of the third housing portion 26, through which fluid connection is achieved from the interior of the arc-extinguishing chamber 14 to the metal mesh 70. This opening 72 is disposed directly next to the flange section 40 on the sidewall 50, which is axially positioned at the first predetermined break point 74 of the busbar 16.

[0041] In addition to the first predetermined break point 74, the busbar 16 also includes a second predetermined break point 76 located at a certain distance therefrom. In this exemplary embodiment, the two predetermined break points 74 and 76 are formed such that the busbar segment 42 to be separated, located between the two predetermined break points 74 and 76, is offset relative to the busbar segments 78 adjacent to the two predetermined break points 74 and 76 in an axial direction corresponding to the direction of movement X of the separating element 34, wherein these busbar segments 78 are surrounded and thereby fixed by the third housing portion 26. Therefore, the busbar segment 42 to be separated is connected to the adjacent busbar segment 78 only by 10-60% of its cross-section.

[0042] When viewed along the main extension direction Y of the busbar 16, the first predetermined break point 74 is located directly opposite the first dividing edge 80 of the separating element 34 formed on the first end, where the distance between the separating element 34 and the busbar segment 42 to be separated is minimal. When viewed laterally along the main extension direction Y of the busbar 16, the dividing surface 82 of the separating element 34 first extends along the shortest distance parallel to the busbar segment 42 on the short segment 83 of the dividing edge 80, and then gradually deviates from the busbar segment 42 toward the second predetermined break point 76, thus having an inclined profile, such that the distance between the second end 84, which is furthest from the dividing edge 80, and the busbar segment 42 is maximized. As mentioned above, when the separating element 34 is in the untriggered state, the first predetermined break point 74 is located directly below the dividing edge 80 of the separating element 34, while when viewed along the main extension direction of the busbar 16, the distance between the second end 84 and the second predetermined break point 76 is greater than the axial extension of the busbar segment 42 to be separated. In this region, when viewed along the main extension direction of the busbar 16, between the second end 84 of the separation element 34 and the second predetermined break point 76, there is a limit stop 86 in the arc-extinguishing chamber 14, which is formed on the flange section 40 of the third housing portion 26.

[0043] After actuator 32 is triggered and busbar segment 42 is separated at the first predetermined fracture point 74, separation element 34 is then further driven into arc-extinguishing chamber 14. During this process, busbar segment 42 twists into arc-extinguishing chamber 14 around the second predetermined fracture point 76 until its underside impacts the limiting stop 86. Therefore, the continued movement of separation element 34 generates shear stress in the region of the second predetermined fracture point 76, ultimately leading to fracture at that point. Since separation element 34 has now moved quite deeply into arc-extinguishing chamber 14, and the movement of the busbar segment 42 to be separated is purely rotational around the second predetermined fracture point 76, this movement continues after fracture. This means that busbar segment 42 twists towards the stop rib 60, which absorbs its kinetic energy. During this process, busbar segment 42 is twisted into cavity 88, one side of which is defined by the inner wall 58 of the second housing portion 24, and the other side by the side surface 90 of the separating element 34 facing the second predetermined break point 76. Therefore, in the region of cavity 88, the distance between adjacent busbar segments 78 and the base 62 must be chosen to be greater than the length of the separated busbar segment 42 to ensure that there is no longer any contact between the adjacent busbar segments 78 fixed in the housing 10 and the separated busbar segment 42. In the triggered state, viewed along the direction of movement of the separating element 34, the distance between the stop rib 60 and the separating element 34 must also be chosen to be greater than the length of the busbar segment 42 before triggering.

[0044] The cavity 88 is further bounded in the region of the base 62 by a limiting rod 92 that extends into the arc-extinguishing chamber 14 toward the first housing portion 22, on the one hand restricting the separated busbar segment 42 to its final upright position, and on the other hand serving as a limiter for the damping element 68.

[0045] The damping element 68 is made of an elastomer and has a damping body 96 from which a deformable structure 98 extends to the base 62 of the second housing portion 24. The deformable structure 98 is designed in the form of ribs 100, the ends of which allow the damping element 68 to be supported on the base 62.

[0046] The damping element 68 has a support surface 102 on the damping body 96 facing the separating element 34. A surface region 104 on the support surface 102 of the damping body 96 is adjacent to the sidewall 50 with the opening 72 and is axially arranged opposite to a segment 105 of the separating edge 80, which is positioned closest to the first predetermined break point 74 in the untriggered state. This surface region 104 is shaped to be complementary to the segment 105 of the separating edge 80. In this exemplary embodiment, the surface region 104 has an inwardly curved portion 106 facing the separating element 34, and the separating element 34 has a correspondingly inwardly pointing cavity 108 in this region. Viewed along the extension direction of the generatrix 16, adjacent to the surface region 104 is a sealing lip 110, which extends from the sidewall 52 to the sidewall 54 of the guide element 48 on the support surface 102 of the damping element 68.

[0047] According to the invention, stiffeners 111 are formed on each sidewall 52, 54, facing the separating element 34, i.e., towards the interior of the arc-extinguishing chamber 14. The stiffeners 111 extend along the direction of movement of the separating element 34, and thus extend along the extension direction of the sidewalls 52, 54 to the support surface 102, thereby extending along the entire area traversed by the separating element 34. The height of these stiffeners 111, i.e., their extension into the arc-extinguishing chamber 14, is selected such that the separating element 34 always abuts against at least these stiffeners 111 during its movement. In this exemplary embodiment, the stiffeners 111 are arranged opposite each other, and the distance between them is selected such that, when viewed in the same direction, this distance is slightly less than the width of the separating element 34 in this area, such that the separating element 34 shears off the top of the stiffeners 111 as it moves through the guide element 48 and is guided along the guide element 48 without gaps.

[0048] Sidewalls 52 and 54 extend approximately at right angles from the ends of sidewall 50, thereby defining the arc-extinguishing chamber 14 on three sides. The sealing lip 110 extends perpendicular to the main extension direction of the busbar 16 and approximately parallel to the separating edge 80 of the separating element 34, while the stiffener 111, when viewed from the separating edge 80 along the separating surface, is positioned just behind the sealing lip 110. In the radially outer region 112, the damping element 68 has shoulders 114 on three sides, wherein the distance from the busbar 16 to the surface 116 facing the busbar 16 is correspondingly less than the distance from the busbar 16 to the rest of the support surface 102 of the damping element 68, and the damping element 68 protrudes beneath the sidewalls 50, 52, and 54 by means of this surface 116. During assembly, the sidewalls 50, 52, and 54 are pressed against the surface 116 of the shoulders 114, thereby securely clamping the damping element 68 at its position on the base 62 of the second housing portion 24. During assembly, the limiting rod 92 prevents it from moving toward the fourth side 57. The radially outer region 112 of the compression damping element 68 is used to form a seal between the damping element 68 and the third housing portion 26, and thereby between it and the three side walls 50, 52, 54 of the arc-extinguishing chamber 14.

[0049] In an emergency, such as a vehicle accident, the pyrotechnic actuator 32 is triggered. The separating element 34 is pushed towards the busbar 16 by the explosive force, separating the busbar segment 42 from the rest of the busbar at the first predetermined fracture point 74. Due to the high voltage, an electric arc is generated between the free ends of the busbar in the region of the first predetermined fracture point 74. This arc can propagate through the opening 72 to the metal mesh 70, which is melted by thermal energy, thus cooling the arc. However, initially, the arc is limited to connecting the busbar segment 78 adjacent to the first predetermined fracture point 74 with the disconnected end of the separated busbar segment 42 twisted into the arc-extinguishing chamber 14, and continues to expand as the busbar segment 42 rotates further. As the separating element 34 continues to move within its range of motion, the gap between the separating element 34 and the damping element 68 through which the arc passes gradually decreases until the separating element 34 finally impacts the support surface 102. Through this impact, kinetic energy is first converted into the deformation energy of the rib 100. Furthermore, the gap between the separating element 34 and the damping element 68 is completely sealed because the separating element 34 first comes into high-speed contact with the sealing lip 110, thereby generating strong pressure very quickly over a very small area, which in turn has the effect of extinguishing or interrupting the arc in that area. Throughout the movement of the separating element 34 and in its final position, arc flashover through the gap between the separating element 34 and the guiding element 48 is also prevented because the stiffener 111 ensures that there is absolutely no gap between the sidewalls 52, 54 and the separating element 34. Subsequent movement significantly increases the support surface between the damping element 68 and the separating element 34 because the separating edge 80 of the separating element 34 abuts against a surface area 104 complementary to the separating edge, which extends from the sidewall 52 to the sidewall 54, thus forming a wide sealing surface that effectively prevents further arc flashover. This means that, through the combined action of the damping element 68 and the separation element 34, as well as the stiffeners 111 of the sidewalls 52 and 54 and the separation element 34, the space 117 (where the free end of the fixed busbar segment 78 adjacent to the first predetermined break point 74 is arranged in the space 117, and the space is defined by the first sidewall 50 and the sidewalls 52 and 54 up to the stiffener 111) is completely sealed and isolated from the space 118, which is formed on the fourth side surface 57 of the arc-extinguishing chamber 14. The busbar segment 42 first twists into the space and then breaks therein, and a cavity 88 for receiving the busbar segment 42 is formed in the space.

[0050] Furthermore, when busbar 16 is cut at the second predetermined break point 76, a further arc is generated, thereby increasing the total length of the existing arc to the point where the resistance increases to the point where the break voltage exceeds the power supply voltage. These measures enable the arc to be completely and rapidly extinguished and cooled within a short time.

[0051] In addition to extinguishing and cooling the electric arc, it is also necessary to reduce the pressure generated by the igniter explosion, the melting of the metal mesh 70, and the resulting electric arc. To guide these airflows in a controlled manner into the pressure-reducing volume 38 located between the inner wall section 30 and the outer wall section 36 of the actuation chamber 12, channels 120 are formed in the base 62 of the second housing portion 24. These channels begin in the region below the metal mesh 70 and extend along both sides of the base 62 of the second housing portion 24, initially extending downwards in the form of grooves to below the damping element 68. From there, the channels 120 extend laterally to the opposing outer wall 66 of the second housing portion 24. From there, the channels 120 extend upwards on the inner wall surface of the outer wall 66 in the form of grooved recesses until they converge into the flow holes 43 of the third housing portion 26, which are in fluid communication with the pressure-reducing volume 38, thus allowing for reliable pressure reduction using the available volume.

[0052] Therefore, a fuse device has been invented that, within a small installation space, can prevent prolonged short circuits and resulting personal injury by rapidly and reliably extinguishing the arc, and effectively avoid emissions. High cutting performance can still be achieved with good damping and rapid extinguishing. This also allows for maintaining a relatively thin wall thickness, as pressure is rapidly reduced, the arc is quickly and reliably extinguished, and the kinetic energy of the separating element is effectively absorbed. In particular, all gaps between the first separating end of the sheared busbar segment and the fixed end of the busbar segment adjacent to the first predetermined break point are reliably sealed.

[0053] Obviously, the scope of protection is not limited to the described embodiment, but various modifications can be made. In particular, other housing separation methods or the shapes of the components used can be employed. If necessary, busbars with predetermined fracture points and different design structures can be used, or damped impacts can be achieved through improved components, wherein the space formed on the side of the separating element opposite to the free end of the fixed busbar section adjacent to the first predetermined fracture point must be reliably isolated by the first predetermined fracture point, and said space must be sealed and separated from the free end of the fixed busbar section. For this purpose, the stiffeners can also be easily offset within the support surface of the separating element compared to the exemplary embodiment. When a cylindrical piston is used, the guide element can also be a hollow cylinder. In this case, a corresponding seal can also be created between the guide element and the separating element by the stiffeners. Depending on the hardness of the selected guide element and separating element, the separating element may also be cut into by the stiffeners during the movement of the separating element, rather than the stiffeners being sheared off.

Claims

1. A fuse device for high-voltage applications, comprising: Shell (10); An actuation chamber (12) and an arc-extinguishing chamber (14) are formed within the housing (10). A busbar (16) passes through the housing (10) and extends between the actuation chamber (12) and the arc-extinguishing chamber (14); A separating element (34), which can be moved from the actuation chamber (12) toward the busbar (16) by means of an actuator (32), and by means of the separating element, a busbar segment (42) can be moved into the arc-extinguishing chamber (14) to cut the busbar (16) at a first predetermined break point (74), and A guide element (48) extends into the arc-extinguishing chamber (14) and has two opposing sidewalls (52, 54) that extend to define a support surface (102) of the arc-extinguishing chamber (14) along the direction of movement of the separating element (34). Its features are, Ribs (111) extending along the direction of movement of the separating element (34) are formed on the two sidewalls (52, 54). The ribs extend at least along the length of the sidewalls (52, 54) to the support surface (102), which defines the arc-extinguishing chamber (14) along the direction of movement of the separating element (34). When the separating element (34) moves into the arc-extinguishing chamber (14), the separating element (34) abuts against the support surface.

2. The fuse device for high-voltage applications according to claim 1, characterized in that, The stiffener (111) is at least partially sheared off by the separating element (34) after the separating element (34) has passed its travel range.

3. The fuse device for high-voltage applications according to claim 1 or 2, characterized in that, After passing through the travel range of the separating element (34), it is at least partially cut by the stiffener (111).

4. A fuse device for high-voltage applications according to any one of the preceding claims, characterized in that, After the separation element (34) has passed its travel range, the support surface (102) for the separation element (34) is formed by a damping element (68) disposed in the arc-extinguishing chamber (14) on the base (62) of the housing (10), and after the separation element (34) has passed its travel range, the separation element (34) abuts against the damping element.

5. The fuse device for high-voltage applications according to claim 4, characterized in that, After the separating element (34) has passed its travel range, the separating element (34), the stiffener and the damping element (68) completely isolate the space (118) in which the separated busbar section (42) is arranged from the space (117) in which the free end of the fixed busbar section (78) forming the first predetermined break point (74) is arranged.

6. The fuse device for high-voltage applications according to claim 4 or 5, characterized in that, The damping element (68) is fixed to the base (62) by at least two sidewalls (52, 54) of the guide element (48).

7. The fuse device for high-voltage applications according to any one of claims 4 to 6, characterized in that, The damping element (68) is made of an elastomer.

8. A fuse device for high-voltage applications according to any one of the preceding claims, characterized in that, The damping element (68) has a deformable structure (98) through which the damping element (68) abuts against the base (62) of the arc-extinguishing chamber (14).

9. A fuse device for high-voltage applications according to any one of the preceding claims, characterized in that, The separating element (34) has a first separating edge (80). When viewed along the direction of movement of the separating element (34) in the untriggered state, the first separating edge (80) is at the smallest distance from the busbar segment (42) to be separated. The shape of the segment (105) of the separating edge (80) at the smallest distance from the first predetermined break point (74) in the main extension direction of the busbar (16) is complementary to the surface area (104) of the damping element (68), which is arranged opposite to the segment (105) of the separating edge (80) along the direction of movement of the separating element (34).

10. The fuse device for high-voltage applications according to claim 9, characterized in that, On the support surface (102) of the damping element (68), a sealing lip (110) is formed adjacent to the surface region (104) which is shaped in a complementary manner, and the sealing lip is at its minimum distance from the separation element (34) before the safety device is triggered.

11. The fuse device for high-voltage applications according to claim 10, characterized in that, The sealing lip (110) extends across the entire width of the arc-extinguishing chamber (14) to the stiffening plate (111) of the sidewall (52, 54) of the guide element (48) of the arc-extinguishing chamber (14).

12. The fuse device for high-voltage applications according to any one of claims 5 to 11, characterized in that, The space (117) defined by the separating element (34) is fluidly connected to the metal mesh (70), wherein the free end of the fixed busbar section (78) forming the first predetermined break point (74) is arranged in the space (117).

13. The fuse device for high-voltage applications according to any one of claims 1 to 12, characterized in that, The guiding element (48) has a third sidewall (50) that connects two opposing sidewalls (52, 54) to each other and extends parallel to the first predetermined break point (74) into the arc-extinguishing chamber (14). After completing the travel range, the side surface (90) of the separating element (34) facing the first predetermined break point (74) is positioned opposite the third sidewall.

14. The fuse device for high-voltage applications according to claim 13, characterized in that, The metal mesh (70) is disposed on the side of the third sidewall (50) opposite to the separating element (34). The metal mesh is fluidly connected to the space (117) through an opening (72) in the third sidewall (50). The free end of the fixed busbar section (78) forming the first predetermined break point (74) is arranged in the space (117).

15. The fuse device for high-voltage applications according to any one of claims 4 to 14, characterized in that, The housing (10) is constructed in three parts, wherein a first housing part (22) is radially surrounding the actuation chamber (12), a second housing part (24) is radially surrounding the arc-extinguishing chamber (14) and forming the base (62) of the arc-extinguishing chamber (14), the damping element (68) is disposed on the base, a third housing part (26) is surrounding the busbar (16) and is disposed between the first housing part (22) and the second housing part (24) with a flange section (40), and the guide element (48) together with the sidewalls (52, 54) extends from the third housing part.

16. The fuse device for high-voltage applications according to any one of claims 9 to 15, characterized in that, In the untriggered state, the distance from the separating surface (82) of the separating element (34) to the busbar (16) increases from the first separating edge (80) toward the opposite second end (84).

17. A fuse device for high-voltage applications according to any one of the preceding claims, characterized in that, The busbar (16) has a second predetermined break point (76), and the busbar segment (42) to be separated is able to twist around the second predetermined break point after the busbar (16) is cut at the first predetermined break point (74), wherein a cavity (88) is formed in the space (118) between the damping element (68) and the sidewall (56) of the second housing portion (24) defining the arc-extinguishing chamber (14), and the busbar segment (42) to be separated is disposed in the cavity next to the separating element (34) after the busbar segment (42) is cut.

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