Protection device for high-voltage applications

Abstract

Known protection devices for high-voltage applications comprise a housing (10), an actuation chamber (12) and an arcing chamber (14), which are formed in the housing (10), a bus bar (16) extending through the housing (10) and between the actuation chamber (12) and the arcing chamber (14), and a separating body (34) which can be moved out of the actuation chamber (12) against the bus bar (16) by means of an actuator (32) and by means of which a bus bar portion (42) can be moved into the arcing chamber (14) in order to sever the bus bar (16) at a first predetermined breaking point (74). In order to be able to realize bursting of the housing even with small wall thicknesses, according to the invention the kinetic energy of the bus bar portion to be detached is absorbed, since deformable stop ribs (60) protruding into the arcing chamber (14) are formed on the housing (10), against which stop ribs the movable bus bar portion (42) can be moved by the movement of the separating body (34) when the protection device is tripped.

Description

[0001] DESCRIPTION

[0002] Safety device for high-voltage applications

[0003] The invention relates to a safety device for high-voltage applications, comprising a housing, an actuation chamber and an arcing chamber formed in the housing, a busbar extending through the housing and between the actuation chamber and the arcing chamber, a separating body which can be displaced from the actuation chamber against the busbar by means of an actuator, through which separating body a busbar section can be displaced into the arcing chamber for severing the busbar at a first predetermined breaking point.

[0004] Such safety devices are usually designed with a pyrotechnic igniter as an actuator and are used, particularly in vehicles with high-voltage applications such as hybrid vehicles or fully electric vehicles, to disconnect the power line between the battery and the consumers, in particular the vehicle's drive, in the event of an accident in a few thousandths of a second in order to avoid short circuits.

[0005] However, due to the high voltages, arcs occur between the free ends of the busbar when the busbars are separated, causing current to continue to flow for several seconds and resulting in extremely high short-circuit currents that can cause electric shocks to vehicle occupants or emergency personnel, which can be life-threatening. Since these arcs cannot be completely avoided, precautions must be taken to extinguish them as quickly as possible. Furthermore, the triggering of the actuator generates high kinetic energy in the separating body and then, after the busbar is separated, this also generates high kinetic energy in the severed busbar section. This occurs both when the busbar section is separated on one side and rotated around a pivot point, and when this busbar section is separated on both sides.The kinetic energy of the moving busbar section must be absorbed by the housing against which the busbar section is accelerated, without causing damage to the housing. Particularly when using thin walls, insufficient energy absorption could cause the housing to burst, releasing the gas into the environment. This gas is generated by the expansion during heating from the arc and by the explosion when a pyrotechnic igniter is used.

[0006] For example, US Pat. No. 11,081,303 B2 describes a pyrotechnic safety device in which a rubber ring is arranged on the floor of the extinguishing chamber, through which the kinetic energy of the separating piston and the busbar is converted into deformation energy. After triggering, the severed busbar section lies between the separating piston and the rubber ring. This means that an additional component must be used to absorb the energy of both the separating piston and the busbar section.

[0007] The object is therefore to create a safety device for high-voltage applications that, when triggered, reliably absorbs the kinetic energy of the severed busbar section without the need for additional components, without requiring a housing with very thick walls. This object is achieved by a safety device for high-voltage applications having the features of main claim 1.

[0008] The safety device according to the invention for high-voltage applications has a housing in which an actuation chamber and an arcing chamber are formed. The housing can in particular be designed in several parts and, for example, have at least a second housing part which surrounds the arcing chamber, and a first housing part which surrounds the actuation chamber. An actuation chamber is understood to be a space in which an actuator is at least partially arranged. This can in particular be a pyrotechnic igniter, the triggering of which creates pressure which accelerates a separating body out of the actuation chamber. An arcing chamber is understood to be a space into which a busbar section is displaced, whereby the busbar is separated into at least two parts.The high voltages present create an arc, also known as plasma, between the separated busbar sections in the arcing chamber, which leads to burns. In order to keep these arcs as short as possible, this arc must be extinguished as quickly as possible. The fuse device also has a busbar that extends through the housing and between the actuation chamber and the arcing chamber. Furthermore, when the fuse device is not triggered, a separating body is arranged in the actuation chamber that can be moved against the busbar by means of the actuator. When the actuator is triggered, this separating body separates a busbar section at a predetermined breaking point to sever the busbar and moves it into the arcing chamber. In this way, it is itself at least partially moved from the actuation chamber into the arcing chamber.This displacement can be achieved either by rotation around a second end of the movable busbar section or by a straight displacement into the arcing chamber with separation on both sides. A combined movement is also possible, in which the movable busbar section is first rotated around its second end and then a second separation occurs in the area of ​​this second end by the opposite end of the isolating body.

[0009] According to the invention, deformable stop ribs projecting into the arcing chamber are formed on the housing, against which the movable busbar section can be displaced upon triggering of the safety device by the movement of the separating body. The safety device is triggered by actuating the actuator, in particular by firing the igniter if it is a pyrotechnic actuator. This triggering presses the separating body against the movable busbar section, releasing it from the stationary busbar section at least in the area of ​​the first predetermined breaking point. Accordingly, the movable busbar section is rotated about its opposite end or released at its second predetermined breaking point.In both cases, the busbar section is subjected to high acceleration. In the first case, this acceleration initially occurs in a circular motion, so that the busbar section accelerates against a side wall as it continues to rotate, or in the second case, the acceleration occurs linearly, so that the entire busbar section is accelerated straight towards the floor. The deformable stop ribs, against which the busbar section is accelerated, convert the existing kinetic energy into deformation energy. This can be either elastic or plastic deformation of the stop ribs. In both cases, the energy is dissipated to such an extent that damage to the external housing walls is avoided. Accordingly, the outer walls can be designed with a thinner wall thickness.Furthermore, the design of these stop ribs directly on the housing eliminates the need for additional components or inserts, which simplifies both assembly and production.

[0010] Preferably, the stop ribs extend from an inner wall of the housing that defines the arcing chamber into the arcing chamber. This allows the stop ribs to directly absorb energy while still being supported by the inner wall.

[0011] It is particularly preferred if the stop ribs extend at an angle to the inner wall of the housing. This angled arrangement allows the stop ribs to absorb more energy through elastic deformation, as they are less rigid in the direction of load.

[0012] In a further embodiment, adjacent stop ribs are each inclined in an opposite direction to the inner wall. This prevents lateral movement of the separated busbar section due to a one-sided deformation of the stop ribs.

[0013] Furthermore, it is advantageous if the housing is constructed in three parts, with a first housing part radially surrounding the actuation chamber, a second housing part radially surrounding the arcing chamber and forming a base of the arcing chamber, a third housing part surrounding the busbar, and being arranged with a flange section between the first housing part and the second housing part, with the stop ribs being formed on an inner wall of the second housing part. Such a housing division simplifies assembly and enables easy demolding during production despite the formation of the stop ribs on the second housing part.

[0014] In a further advantageous embodiment, the distance between a separating surface of the separating body and the busbar increases in the non-triggered state from a first separating edge, which in the non-triggered state has the shortest distance to the first predetermined breaking point, in the direction of an opposite second end, wherein the busbar can be rotated about a second end of the movable busbar section. Accordingly, the separating body initially strikes the first predetermined breaking point with the separating edge. The busbar section to be severed is then rotated about the second predetermined breaking point. With such an embodiment, in the triggered state, a space in which the severed busbar section is arranged can be completely separated from a space in which the end of the fixed busbar section pointing towards the first predetermined breaking point is arranged, and on the other hand, the severed busbar section can be accommodated upright next to the separating body.This creates a guided movement so that the stop ribs can be formed specifically at the position where the kinetic energy of the severed busbar section is greatest.

[0015] In a further embodiment of the invention, the second end of the movable busbar section serves as a second predetermined breaking point, at which the busbar section can be sheared off at the second predetermined breaking point after the second end of the separating surface of the separating body reaches the busbar section. This results in a complete separation of the movable busbar section from the stationary busbar section, and consequently an extension of the arc, which accelerates the extinguishing of the arc. The completely severed busbar section can thus fall upright into the space next to the separating body.

[0016] It is particularly preferred if a pocket is formed in the extinguishing chamber of the second housing part, in which the

[0017] After the separation, the busbar section is positioned adjacent to the separating body and is limited by the stop ribs on the side opposite the separating body. Accordingly, both the energy from the rotational movement and that from the second separation are absorbed by the stop ribs. The position of the busbar section after the separation, determined by the guided movement, allows the stop ribs and the housing walls to be precisely designed for the known forces acting in order to prevent the housing from bursting while simultaneously using the smallest possible wall thickness.

[0018] In a further advantageous embodiment of the invention, the stop ribs extend from a side wall and a base of the housing to a free end, which, in the tripped state, is directed toward the isolating body, into the arcing chamber. The two-sided attachment of the stop ribs ensures high stability of the stop ribs in the housing and prevents excessive forces acting on a single housing wall. At the same time, it is ensured that the severed busbar section is accelerated exclusively against the stop ribs, so that the kinetic energy from its movement is fully absorbed by the stop ribs through elastic and plastic deformation.

[0019] Furthermore, the free ends of the stop ribs, which point towards the isolating body in the triggered state, extend less into the arcing chamber as the distance from the floor increases. This design enables easy demolding during housing manufacture, and this shape is also adapted to the movement of the busbar section when it is first rotated and then sheared off. Since the shearing takes place at the second predetermined breaking point before the busbar section is rotated by 90°, a combined rotational and translational movement occurs. The inventive arrangement of the stop ribs makes it possible to achieve an approximately flat impact of the busbar section on the stop ribs, so that the latter are loaded approximately evenly across their height.

[0020] Accordingly, the free ends of the stop ribs, which face the isolating element in the triggered state, form a plane that, when the safety device is not triggered, forms an angle of less than 90° to the movable busbar section. A motion vector of the busbar section is approximately perpendicular to this plane, creating a force that is distributed across the surface and enabling uniform energy absorption.

[0021] Furthermore, it is advantageous if a limiting web is formed on the bottom of the housing, which has a distance from the free ends of the stop ribs that corresponds at least to the thickness of the busbar section to be severed and by which the pocket is delimited in the area of ​​the bottom. This selected distance of the limiting web allows the busbar section to slide into this pocket after complete release, preventing it from slipping into an area below the separating body. The position of the severed busbar section is thus determined after release by this design.

[0022] Preferably, the side wall from which the stop ribs extend is spaced from an outer wall formed on the side of the side wall opposite the separating body in the triggered state, thereby creating a double-walled housing with very high strength. Bursting of the housing can thus be reliably prevented, particularly since the force exerted by the movement of the severed busbar section does not act directly on an outer wall of the housing. This creates a safety device for high-voltage applications in which the kinetic energy of the busbar section is reliably absorbed and excessive stress on the outer housing is prevented. The stop ribs serve as a type of sacrificial ribs that are elastically and plastically deformable and can also partially melt due to the resulting arc.This allows both thermal and kinetic energy to be dissipated without risking overloading the outer casing. Accordingly, the outer casing can be manufactured with relatively thin walls.

[0023] An embodiment of a safety device according to the invention for high-voltage applications is illustrated in the figures and is described below using a safety device designed as a pyrotechnic interrupter device. The terms "axial" and "radial" are used below depending on the movement of the separating body of the safety device, so that an axial direction corresponds to the direction of movement of the separating body, while a radial direction forms a component perpendicular to the direction of movement.

[0024] Figure 1 shows a side view of an inventive

[0025] Safety device in section view before actuation.

[0026] Figure 2 shows the side view of the inventive

[0027] Safety device from Figure 1 in a sectional view after actuation.

[0028] Figure 3 shows a side view of the safety device according to the invention shown in Figure 1, rotated by 90°, in a sectional view prior to actuation. Figure 4 shows a top view in a sectional view through an extinguishing chamber of the safety device.

[0029] The safety device according to the invention, shown in the figures, is designed as a pyrotechnic interrupter device and consists of a housing 10, in the interior of which an actuation chamber 12 and an extinguishing chamber 14 are formed, which are separated from one another by a busbar 16 which extends through the housing 10 and via which, for example, a battery of a vehicle is connected to a consumer, such as a drive motor.

[0030] The housing 10 is double-walled, wherein an inner wall 18 at least partially radially delimits the extinguishing chamber 14 and the actuation chamber 12 and an outer wall 20 is arranged radially spaced from the inner wall 18 and delimits the safety device to the outside.

[0031] The housing 10 is constructed in three parts, with a third housing part 26 being clamped between a first housing part 22, in which the actuation chamber 12 is formed centrally, and a second housing part 24, in which the extinguishing chamber 14 is formed, with sealing rings 28 interposed.

[0032] The actuation chamber 12 in the first housing part 22 is radially surrounded by an inner wall 30 of the first housing part 22. An actuator 32, designed as a pyrotechnic igniter, is arranged inside this actuation chamber 12 in the area remote from the extinguishing chamber 14. Furthermore, in the non-triggered state, a separating body 34, which has a piston-like shape, is displaceably arranged inside the actuation chamber 12. This separating body 34 is guided radially at least in sections through the inner wall 30 of the first housing part 22 and axially delimits the actuation chamber 12 in the direction of the actuator 32. Furthermore, the first housing part 22 has an outer wall 36, which is connected to the inner wall 30 via ribs (not shown). A pressure relief volume 38 is formed between the inner wall 30 and the outer wall 36 by the free spaces between the ribs.

[0033] The third housing part 26 has a flange section 40, with which the third housing part 26 is clamped between the first housing part 22 and the second housing part 24. This flange section 40 surrounds the busbar 16 on all sides, with the exception of a busbar section 42 to be separated, which axially directly borders the actuation chamber 12 and the arcing chamber 14 before triggering. This busbar section 42 is delimited only on its radial sides by the third housing part 26, while the two sides of the busbar section 42 facing the actuation chamber 12 and the arcing chamber 14 are exposed to the actuation chamber 12 and the arcing chamber 14. Furthermore, two or more flow openings 43 are formed in the flange section 40, which are arranged in an axial extension of the pressure reduction volume 38 of the first housing part 22.A guide section 44 extends axially from the flange section 40, which guide section engages in a receptacle 46 on the inner wall 30 of the first housing part 22 in the region of the first housing part 22 facing the third housing part 26 and radially delimits the actuation chamber 12 in this region and thus guides the separating body 34.

[0034] In addition, the third housing part 26 has a guide element 48 that extends into the second housing part 24 and has three side walls 50, 52, 54 that delimit the arcing chamber 14 on three sides. The third side wall 50 extends approximately parallel to the first predetermined breaking point and thus perpendicular to the main extension direction of the busbar 16, and the two opposite side walls 52, 54 are arranged opposite longitudinal side surfaces 55 of the busbar section to be severed. This guide element 48 is open on a fourth side 57. On this side, a fourth side wall 56 of the arcing chamber 14 is formed by an inner wall 58 of the second housing part 24.

[0035] According to the invention, stop ribs 60 are formed on this inner wall 58 and project into the extinguishing chamber 14. These stop ribs 60 extend from a base 62 along the inner wall 58, with the free end of these stop ribs 60 pointing towards the extinguishing chamber 14. In the area arranged closer to the busbar 16, the free ends of the stop ribs 60 form a common plane which is formed obliquely to the inner wall 58 and forms an angle of approximately 80° to the busbar 16. Accordingly, the free ends of the stop ribs 60, which point towards the isolating body 34 in the triggered state, have a smaller extension into the extinguishing chamber 14 with increasing distance from the base 62 in this area. In the area close to the base 62, the free ends of the stop ribs 60 are arranged approximately perpendicular to the busbar 16.In the present embodiment, a total of four adjacent stop ribs 60 are formed. However, they do not extend perpendicularly to a surface of the inner wall 58, but are inclined by 5° to 10° relative to this perpendicular, with adjacent stop ribs 60 each being inclined to the opposite side. Accordingly, two adjacent V-shaped pairs of ribs are formed.

[0036] The three side walls 50, 52, 54 of the guide element 48, which project toward the bottom 62 of the second housing part 24, are precisely received within wall sections 64 of the second housing part 24, which extend from the bottom 62 toward the first housing part 22. The side walls 50, 52, 54, the wall sections 64, and the side wall 56 of the second housing part 24 are arranged radially spaced from surrounding outer walls 66 of the second housing part 24, which radially delimit the safety device. A damping element 68 is arranged on the bottom 62 and delimits the arcing chamber 14 axially relative to the bottom 62 of the second housing part 24, axially below the separating body 34.Immediately laterally adjacent to the damping element 68, on the side of the arcing chamber 14 opposite the stop ribs 60, there is also arranged on the floor 62 a metal mesh 70 which extends axially between the side wall 50 and the outer wall 66 surrounding the arcing chamber 14. The metal mesh 70 extends axially to just before the flange section 40 of the third housing part 26. An opening 72 is formed in the side wall 50 of the guide element 48 of the third housing part 26, via which opening a fluidic connection is established from the interior of the arcing chamber 14 to the metal mesh 70. This opening 72 is formed immediately adjacent to the flange section 40, specifically on the side wall 50, which is arranged in the axial extension of a first predetermined breaking point 74 of the busbar 16.

[0037] In addition to the first predetermined breaking point 74, the busbar 16 also has a second predetermined breaking point 76 spaced apart therefrom. In the present exemplary embodiment, the two predetermined breaking points 74, 76 are formed by arranging the busbar section 42 to be severed between the two predetermined breaking points 74, 76, offset in an axial direction corresponding to the direction of movement X of the separating body 34, relative to the busbar sections 78 adjacent to the predetermined breaking points 74, 76, which are surrounded by the third housing part 26 and thus fixed. As a result, the busbar section 42 to be severed is only 10-60% connected to the adjacent busbar sections 78 in cross-section.

[0038] Viewed in a main extension direction Y of the busbar 16, the first predetermined breaking point 74 is located directly opposite a first separating edge 80 of the separating body 34 formed at a first end, at which end the separating body 34 has the shortest distance from the busbar section 42 to be separated. A separating surface 82 of the separating body 34 extends in cross-section in the main extension direction Y of the busbar 16, initially over a short section 83 of the separating edge 80 with a shortest distance parallel to the busbar section 42 and then has a distance from the busbar section 42 that steadily increases in the direction of the second predetermined breaking point 76 and is thus formed obliquely, so that the second end 84 remote from the separating edge 80 has the greatest distance from the busbar section 42.While the first predetermined breaking point 74, as already mentioned, is arranged directly below the separating edge 80 of the separating body 34 in the non-triggered state of the separating body 34, the second end 84, viewed in the main extension direction of the busbar 16, has a distance from the second predetermined breaking point 76 which is greater than the axial extension of the busbar section 42 to be severed. In this area between the second end 84 of the separating body 34 and the second predetermined breaking point 76, viewed in the main extension direction of the busbar 16, there is a stop 86 in the arcing chamber 14 which is formed on the flange section 40 of the third housing part 26.

[0039] After the actuator 32 has been triggered and the busbar section 42 has been severed at the first predetermined breaking point 74, the separating body 34 is subsequently driven further into the arcing chamber 14. The busbar section 42 is rotated around the second predetermined breaking point 76 into the arcing chamber 14 until the underside of the busbar section 42 strikes the stop 86. The continued movement of the separating body 34 creates a shear stress in the area of ​​the second predetermined breaking point 76, which ultimately leads to a fracture at the second predetermined breaking point 76. Since at this point in time the separating body 34 has already penetrated relatively far into the arcing chamber 14 and the movement of the busbar section 42 to be severed is purely rotational around the second predetermined breaking point 76, this movement is continued after the separation and is superimposed by the downward movement towards the floor 62.This results in the busbar section 42 being rotated against the stop ribs 60 on the one hand and, in an inclined position, performing an accelerated movement in the direction of the inner wall 58 and the base 62 on the other. The busbar section 42 then strikes the stop ribs 60 with its flat underside, approximately flat. These are deformed by the stop, on the one hand elastically in opposite directions depending on the inclined position, but also plastically due to the high kinetic energy. This deformation absorbs the kinetic energy or converts it into deformation energy. The busbar section 42 is rotated into a pocket 88, which is laterally delimited on the one hand by the inner wall 58 of the second housing part 24 or the stop ribs 60 and on the other hand by a side surface 90 of the separating body 34 directed towards the second predetermined breaking point 76.For this purpose, the distance between the adjacent busbar sections 78 and the base 62 in the area of ​​the pocket 88 must be selected such that it is greater than the length of the severed busbar section 42, thus ensuring that there is no longer any contact between the adjacent busbar sections 78 fastened in the housing 10 and the severed busbar section 42. In addition, the distance of the stop ribs 60 from the separating body 34 in the triggered state must be selected to be greater than the length of the busbar section 42 before triggering, viewed in the direction of movement of the separating body 34.

[0040] In the area of ​​the base 62, the pocket 88 is also delimited by a limiting web 92, which extends in the direction of the first housing part 22 into the arcing chamber 14 and, on the one hand, limits the severed busbar section 42 in its upright final position and, on the other hand, serves as a limiting element for the damping element 68. The severed busbar section thus comes to rest in an upright position in its final position between the stop ribs 60 on one side and the limiting web 92 and the separating body 34 on the other side.

[0041] This damping element 68 is made, in particular, of an elastic plastic and has a damper body 96, from which deformation structures 98 extend to the bottom 62 of the second housing part 24. These deformation structures 98 are designed in the form of ribs 100, with the ends of which the damping element 68 rests on the bottom 62.

[0042] The damping element 68 has a bearing surface 102 on the damper body 96, which is directed towards the separating body 34. A surface area adjacent to the side wall 50 in which the opening 72 is formed

[0043] 104 of the support surface 102 of the damper body 96, which is arranged axially opposite to a section 105 of the separating edge 80, which in the non-triggered state is arranged closest to the first predetermined breaking point 74, is complementary to this section

[0044] 105 of the separating edge 80. In the present exemplary embodiment, this surface region 104 has an inner curvature 106 directed toward the separating body 34, while the separating body 34 has a correspondingly inwardly directed recess 108 in this region. Viewed in the direction of extension of the busbar 16, this surface region 104 is adjoined by a sealing lip 110, which extends from the side wall 52 to the side wall 54 of the guide element 48 on the support surface 102 of the damping element 68.

[0045] On each of the side walls 52, 54, a web 111 is formed, which is directed towards the separating body 34, i.e., into the interior of the extinguishing chamber 14. The webs 111 extend in the direction of movement of the separating body 34 and thus in the direction of extension of the side walls 52, 54 toward and up to the support surface 102 and thus along the entire area of ​​the separating body 34 through which it is to travel. The height of these webs 111, i.e., their extension into the extinguishing chamber 34, is selected such that the separating body 34 always rests at least against these webs 111 during its movement. In the present exemplary embodiment, the webs 111 are arranged opposite one another, and their distance from one another is selected such that it is somewhat smaller than the width of the separating body 34 in this area viewed in the same direction, so that the separating body 34 shears off the webs 111 in the upper area during its movement through the guide element 48 and is guided along the guide element 48 without a gap.

[0046] The side walls 52, 54 extend from the ends of the side wall 50 to define three-sided boundaries of the arcing chamber 14, approximately at right angles to the side wall 50, so that the sealing lip 110 runs perpendicular to the main direction of extension of the busbar 16 and approximately parallel to the separating edge 80 of the separating body 34, while the webs 111 are arranged directly behind the sealing lip 110 when viewed from the separating edge 80 along the separating surface. In a radially outer region 112, the damping element 68 has a shoulder 114 on three sides, the surface 116 of which facing the busbar 16 is correspondingly at a smaller distance from the busbar 16 than the remaining contact surface 102 of the damping element 68, and with which the damping element 68 projects below the side walls 50, 52, 54.During assembly, the side walls 50, 52, 54 are pressed onto the surface 116 of the shoulder 114, thereby clamping the damping element 68 in position on the base 62 of the second housing part 24. Displacement toward the fourth side 57 is prevented during assembly by the limiting web 92. By pressing the radially outer region 112 of the damping element 68 together, a seal is also created between the damping element 68 and the third housing part 26 and thus the three side walls 50, 52, 54 of the extinguishing chamber 14. If an emergency occurs, for example, due to a vehicle accident, the pyrotechnic actuator 32 is triggered. The separating body 34 is pressed against the busbar 16 by the explosion and separates the busbar section 42 at the first predetermined breaking point 76 from the remaining busbar 16. An arc is created in the area of ​​the first predetermined breaking point 76 between the free busbar ends due to the high voltage.This arc can, on the one hand, expand through the opening 72 to the metal mesh 70, which is melted by the thermal energy and thus cools the arc. However, the busbar section 78 adjacent to the first predetermined breaking point 74 and the detached end of the busbar section 42 rotated into the arcing chamber 14 are initially connected by the arc, which continues to expand as the busbar section 42 continues to rotate. As the separating body 34 continues to move through its range of motion, a gap through which the arc passes becomes increasingly smaller between the separating body 34 and the damping element 68 until the separating body 34 finally strikes the support surface 102 and the severed busbar section 42 strikes the stop ribs 60.The impact of the separating body 34 initially converts the kinetic energy into deformation energy of the ribs 100, and the impact of the busbar section converts its kinetic energy into deformation energy of the stop ribs 60. In addition, the gap between the separating body 34 and the damping element 68 is completely sealed, as the separating body 34 initially impacts the sealing lip 110 at high speed, suddenly creating a high contact force on a very small surface, which causes the arc to be pinched off or separated in this area. Arcing through a gap between the separating body 34 and the guide element 48 is also prevented during the entire movement of the separating body 34 and in its end position, as the webs ensure that there is no gap at all between the side walls 52, 54 and the separating body 34.As a result of the following movement, the contact surface between the damping element 68 becomes significantly larger, since the separating body 34 is brought into contact with its separating edge 80 on the complementarily shaped surface area 104 extending from the side wall 52 to the side wall 54, so that a wide sealing surface is created which prevents a renewed flashover of the arc.This means that by means of the damping element 68 and the separating body 34 as well as the webs 111 of the side walls 52, 54 and the separating body 34, a space 117 in which the free end of the region of the fixed busbar section 78 adjacent to the first predetermined breaking point 74 is arranged and which is delimited by the first side wall 50 and the side walls 52, 54 up to the webs 111 is completely and tightly separated from a space 118 which is formed on the fourth side 57 of the arcing chamber 14 and into which the busbar section 42 is first rotated and later torn off and in which the pocket 88 for receiving the busbar section 42 is formed. The stop ribs 60 and the formation of the pocket 88 simultaneously prevent the severed busbar section from reaching the area between the damping element 68 and the separating body 34 after the second predetermined breaking point 78 has been severed.

[0047] In addition, when the busbar 16 is severed at the second predetermined breaking point 76, another arc can occur, increasing the total length of the existing arcs to such an extent that the resistance increases to such an extent that the separation voltage exceeds the source voltage. These measures lead to complete and rapid extinguishing and cooling of the arc within a short time. The energy of the second arc is also partially absorbed by the stop ribs 60, which can partially melt. In addition to extinguishing and cooling the arc, the pressure generated by the explosion of the igniter and by the melting of the metal mesh 70 and the resulting arc must also be reduced.In order to guide this gas flow into the pressure reduction volume 38 available 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 part 24. These channels extend from the area below the metal mesh 70 on both sides of the second housing part 24 along the base 62, initially in a groove shape to below the damping element 68. From here, the channels 120 extend on both sides to the opposite outer walls 66 of the second housing part 24. From here, the channels 120 extend upward as groove-shaped depressions on the inner wall surface of the outer walls 66 until they merge into the flow openings 43 of the third housing part 26, which in turn are fluidically connected to the pressure reduction volume 38, so that the pressure can be reliably reduced via the available volumes.

[0048] This creates a safety device that can be used in a small installation space to quickly and reliably extinguish the arc, thus avoiding prolonged short circuits and the resulting injuries and reliably preventing emissions. Nevertheless, high isolating performance is achieved through the effective damping and absorption of the kinetic energy of the moving parts by the damping element and the stop ribs. This also allows the wall thicknesses to be kept relatively thin, as this results in rapid pressure relief, rapid and reliable arc extinguishing, and effective absorption of the kinetic energy of the isolating body and the severed busbar section. In particular, the kinetic energy of the severed busbar section is almost completely absorbed by the design, arrangement, and shape of the stop ribs inside the arcing chamber, significantly reducing the load on the outer walls.

[0049] It should be clear that the scope of protection is not limited to the described embodiment, but various modifications are possible. In particular, different housing divisions or shapes of the components used can be provided. If necessary, a busbar with differently designed predetermined breaking points can also be used, or the stop ribs can be attached differently to one another or to a different inner wall. It is only necessary to ensure that the position and direction of extension of the stop ribs are adapted to the movement and impact point of the severed busbar section. For example, the ribs can also be attached to the floor if the predetermined breaking points are severed at the same time, resulting in a translational movement of the busbar section, or they can be arranged in a straight line on a side wall if a pure rotary movement occurs and only one predetermined breaking point is formed.

Claims

Pierburg GmbH, 41460 Neuss PATENT CLAIMS 1. A safety device for high-voltage applications with a housing (10), an actuation chamber (12) and an arcing chamber (14) formed in the housing (10), a busbar (16) extending through the housing (10) and between the actuation chamber (12) and the arcing chamber (14), a separating body (34) which can be displaced from the actuation chamber (12) against the busbar (16) by means of an actuator (32), through which separating body a busbar section (42) can be displaced into the arcing chamber (14) for severing the busbar (16) at a first predetermined breaking point (74), characterized in that deformable stop ribs (60) projecting into the arcing chamber (14) are formed on the housing (10), against which stop ribs the movable busbar section (42) can be displaced by the movement of the separating body (34) when the safety device is triggered.

2. Fuse device for high-voltage applications according to claim 1, characterized in that the stop ribs (60) extend from an inner wall (58) of the housing (10) delimiting the arcing chamber (14) into the arcing chamber (14).

3. Safety device for high-voltage applications according to claim 2, characterized in that the stop ribs (60) each extend obliquely to the inner wall (58) of the housing (10).

4. Safety device for high-voltage applications according to claim 3, characterized in that stop ribs (60) arranged next to one another are each inclined in an opposite direction to the inner wall (58).

5. Fuse device for high-voltage applications according to one of the preceding claims, characterized in that the housing (10) is constructed in three parts, wherein a first housing part (22) radially surrounds the actuation chamber (12), a second housing part (24) radially surrounds the arcing chamber (14), a third housing part (26) surrounds the busbar (16), and is arranged with a flange section (40) between the first housing part (22) and the second housing part (24), wherein the stop ribs (60) are formed on the inner wall (58) of the second housing part (24).

6. Fuse device for high-voltage applications according to one of the preceding claims, characterized in that the distance of a separating surface (82) of the separating body (34) to the busbar (16) in the non-triggered state increases from a first separating edge (80), which in the non-triggered state has a shortest distance to the first predetermined breaking point (74), in the direction of an opposite second end (84) and the busbar (16) is rotatable about a second end of the movable busbar section (42).

7. Safety device for high-voltage applications according to one of the preceding claims, characterized in that the second end of the movable busbar section (42) serves as a second predetermined breaking point (76), at which the movable busbar section (42) can be sheared off at the second predetermined breaking point (76) after the second end (84) of the separating surface (82) of the separating body (34) has reached the movable busbar section (42).

8. Fuse device for high-voltage applications according to one of the preceding claims, characterized in that a pocket (88) is formed in the arcing chamber (14) of the second housing part (24), in which pocket the busbar section (42) to be severed is arranged adjacent to the separating body (34) after the severing and which is delimited on the side opposite the separating body (34) by the stop ribs (60).

9. Fuse device for high-voltage applications according to one of the claims, characterized in that the stop ribs (60) extend from a side wall (56) and a bottom (62) of the housing (10) into the arcing chamber (14) to a free end which, in the triggered state, is directed towards the separating body (34).

10. Fuse device for high-voltage applications according to claim 9, characterized in that the free ends of the stop ribs (60) pointing towards the separating body in the triggered state have a smaller extension into the arcing chamber (14) with increasing distance from the floor (62).

11. Safety device for high-voltage applications according to one of claims 9 or 10, characterized in that the free ends of the stop ribs (60), which are directed towards the separating body (34) in the triggered state, span a plane which, in the non-triggered state of the safety device, encloses an angle of less than 90° to the movable busbar section (42).

12. Fuse device for high-voltage applications according to one of claims 9 to 11, characterized in that a limiting web (92) is formed on the bottom (62) of the housing (10), which has a distance from the free ends of the stop ribs (60) which corresponds at least to a thickness of the busbar section (42) to be severed and by which the pocket (88) is limited in the region of the bottom (62).

13. Safety device for high-voltage applications according to one of claims 9 to 12, characterized in that the side wall (56) from which the stop ribs (60) extend is spaced from an outer wall (66) which is formed on the side of the side wall (56) opposite the separating body (34) in the triggered state.

Images