Power line cutting device for cutting a power line

Abstract

The invention relates to a power line cutting device (1) for cutting a power line (5), comprising a cutting element (3) for cutting the power line (5), wherein the cutting element (3) is designed and movable in such a way that it acts on the power line (5) and thereby cuts a section (51) therefrom. According to the invention, the cutting element (3) has a covering device (31a, 31b) that covers at least a partial section (511a, 511b) of an edge side of the cut-out section (51).

Description

The invention relates to a power line disconnection device for disconnecting a power line according to the preamble of claim 1.In particular in electrically driven vehicles, high electric currents and voltages occur, which pose a risk to the vehicle occupant in the event of an accident. For this reason, emergency shutdown devices are used with which an electrical circuit of the vehicle can be interrupted in a short time. For example, as a component of an emergency shutdown device, line separators are used which can cut through power lines carrying high electrical currents within a few milliseconds. Such a line separator is known, for example, from DE 10 2018 125 059 A9. After the electric line has been cut through, in the case of the previously known line separators, an arc can occur at the cut-off point, which can in turn result in evaporation of conductive material of the electric line. The vaporized material (in particular copper) may form conductive layers, which may degrade the electrical insulation of the portions of the power line formed after the cut-through of the power line.Further power line disconnection devices are described in JP 2013-239 411 A and WO 2023 / 171 087 A1.The problem underlying the invention is to ensure the best possible insulation of the partial sections formed after the current line has been cut through.This problem is solved by providing the power line disconnecting device having the features of claim 1.According to this, a power line separating device is provided which comprises a separating element for separating the power line, wherein the separating element is designed and can be set in motion in such a way that it acts on the power line and in the process separates a part from the power line. The separating element has an overlapping device which overlaps at least a subsection of an edge side (i.e. of a lateral surface) of the separated-out subsection.With the aid of the covering device, the section ("coin") separated from the power line is electrically insulated better with respect to the remaining sections of the power line and / or precipitation of material of the power line on parts of the power line separating device and thus formation of conductive layers which form a conductive connection between the sections of the power line remaining after the coin has been separated out is made more difficult or prevented. In particular, creepage distances for evaporated material are extended. With the aid of the covering device, a high insulation resistance can therefore be realized between the segments of the power line that are separated from one another even immediately after the separation of the power line. Covering the edge side does not necessarily mean that the covering device abuts the edge side. It is also conceivable that there is a distance between the covering device (e.g. its separating wall and / or side wall described further below) and the edge side.It is conceivable that the covering device consists at least partially of an electrically insulating material. The covering of the edge side of the coin takes place at least for a certain period of time after the coin has been separated from the current line. It is conceivable that after this period of time the coin moves away from the separating element and thus from the covering device and the covering is lost.The edge side of the separated-out part extends in particular perpendicularly or at an angle to an upper side and an underside of the part parallel to the upper side. In addition, the edge side runs along an outer periphery of the top side and bottom side. It is conceivable for the covering device to bear against the edge side of the part piece. The covering device can also already overlap the edge side of the section before the section is separated out; for example, in the case that the covering device engages in a predetermined breaking region (for example, a depression) of the power line in an initial state of the power line separating device. This possibility is explained in more detail below.The separating element is in particular designed in the form of a piston which can be set into movement abruptly in the direction of the power line with the aid of a (e.g. pyrotechnic) movement generating device.The covering device covers in particular at least a partial section of the edge side of the separated part which faces an outer partial section (and remains after the separation of the part) of the power line. The covered subsection of the edge side of the subsection is accordingly in particular a section which extends at an angle or perpendicular to a longitudinal direction of the power line. The covering device thus covers in any case in particular not exclusively a section of the edge side of the part piece running in the longitudinal direction of the power line. It is also conceivable for the covering device to cover a partial section of the edge side of the partial piece that has been produced only after the partial piece has been cut out.The covering device is formed by at least two separating walls protruding from an end face of the separating element facing the power line. The partitions are in particular designed-for example, they have a corresponding height-such that they at least partially cover an edge side of the separated part produced by the separating out. The partition walls are in particular integrally connected to the remaining partition element (in particular the end face).It is conceivable for the separating walls to extend along an outer circumference of the end face. For example, the separating walls extend in an arc shape, for example in the form of a circular section (in particular in the case of a cylindrical configuration of the separating element).The covering device has two separating walls which project from the end face of the separating element and are opposite one another, wherein the separating walls each cover a section of the edge side of the separated-out part at least in sections. In other words, the separating walls each cover at least one section of the separated coin-wherein the covered section is oriented in particular at an angle or perpendicular to the longitudinal extension of the power line.In addition, the covering device can have at least one side wall which likewise protrudes from the end face of the separating element and extends parallel to the longitudinal direction of the power line. The side wall thus runs in particular already in an initial state along a section of the edge side of the power line oriented in the longitudinal direction of the power line and thus covers a subsection of the edge side of the cut-out section of the power line oriented in the longitudinal direction after activation of the in particular power line separating device. For example, the height of the side wall (measured from the end face of the separating element) corresponds to the height of the power line or is even greater than the height of the power line.The covering device can also have two side walls which are opposite one another and project from the end face of the separating element and are each oriented parallel to the power line. In particular, the power line is arranged in the power line separating device such that it runs between the two side walls. The side walls form, for example, a receptacle for the power line. It is possible in particular for the inner sides of the side walls facing the power line to extend at least approximately parallel to the power line. By means of the side walls, in particular two partial sections of the edge side of the separated-out part which are situated opposite one another and run parallel to the longitudinal direction of the power line are covered.It is possible for the covering device to cover the edge side of the separated-out part at least approximately completely or at least a major part (e.g. at least 30% or at least 50% of the area of the edge side). The covering of a large part of the edge side takes place, for example, in that the covering device comprises both the above-described separating walls and the side walls.The height of these side walls of the separating element is, for example, greater than the height of the separating walls (the height being measured from the end face of the separating element). It is conceivable for the partition walls to have at least approximately the same height.The separating element is, for example, at least substantially cylindrical (in particular in the manner of a piston).As already mentioned above, the power line separating device can have a movement generating device for generating a movement of the separating element. For example, the movement generating device comprises a pyrotechnic unit which can be ignited with the aid of an electrical signal and which, after its ignition, suddenly releases gases which accelerate the separating element in the direction of the power line.The power line separating device according to the invention comprises, for example, a housing which guides the movement of the separating element. For example, the housing has an upper part and a lower part, wherein, for example, the movement generating device is arranged in the upper part. The separating element is likewise located in the upper part, for example, before activation of the movement generating device. After cutting through the current line, the separating element moves into the lower part, for example. It is also conceivable for the part separated from the power line to also move into the lower part.The invention also relates to a power line device, having a power line and a power line disconnection device according to the invention for disconnecting the power line.It is possible for the power line to have a predetermined breaking region (in particular at least one predetermined breaking line), wherein the separating element of the power line separating device, in an initial position, bears at least partially against the power line in the predetermined breaking region via its covering device. In this way, it is possible to position the separating element and thus the covering device in such a way that the best possible covering (covering) of the edge side of the separated part piece takes place.According to one embodiment of the invention, the predetermined breaking region is formed complementary to at least a part of the covering device. In particular, the course of the predetermined breaking region corresponds to that of the separating walls of the separating element.For example, the predetermined breaking region comprises a depression of the power line, wherein the covering device of the separating element is arranged at least in sections in the depression (e.g. running in an arc shape analogous to the separating element) in the initial state of the separating element. The separating walls can extend into the depression (in particular up to the lowest point thereof) in the starting position of the separating element. The edge side of the part covered by the separating walls here simultaneously forms a section of a side wall of the depression.The invention also relates to a vehicle, in particular an electrically operated vehicle, having an inventive power line disconnection device.The invention is explained in more detail below on the basis of exemplary embodiments with reference to the figures. The following are shown: FIG. 1 shows a power line disconnection device in a sectional illustration before activation; FIG. 2 shows the power line disconnection device from FIG. 1 after activation; FIG. 3 shows an arrangement comprising a power line and a separating element of a power line separating device according to the invention in a sectional illustration; and FIG. 4 shows the separating element from FIG. 3 in a perspective illustration.FIG. 1 shows an exemplary structure of a power line disconnection device 1. The power line separating device 1 comprises a housing 2 formed, for example, from a plastic (for example PA66), having an upper part 21 and a lower part 22. In the initial state of the power line separating device 1 shown in FIG. 1 (before the pyrotechnic unit 4 is ignited), the piston 3 is located in the upper part 21 of the housing 2. the pyrotechnic unit 4 drives the piston 3 after ignition in the direction of a power line designed as a busbar 5 ("bus bar"). The plunger 3 strikes the busbar 5, as a result of which a portion 51, the coin, is separated from the busbar 5. The part 51 moves into the lower part 21 of the housing 2 (cf. FIG. 2 ). In conventional power line separators, the arc mentioned at the beginning (see arcs 6 a, 6 b) can occur between the separated part 51 and outer portions 52 a, 52 bof the busbar 5 which lead out after the part 51 has been separated.FIG. 3 shows a separating element in the form of a bulb 3, with which the occurrence of the arcs after the portion 51 has been separated out is avoided or at least made more difficult. The piston 3 is, for example, a component of a power line device 1 in the manner of FIGS. 1 and 2. for example, the piston 3 is movable with the aid of a pyrotechnic unit in the direction of a power line (the busbar 5) and separates a part 51 from the power line when it hits the power line.The piston 3 comprises an overlapping device in the form of two partitions 31 a, 31 bwhich each project in a web-like manner from an end face 32 of the piston 3 facing the busbar 5. The end face 32 forms an underside of the piston 3 facing the busbar 5. the partitions 31 a, 31 bare designed such that they each cover a subsection 511 a, 511 b(cf. FIG. 1 ) of an edge side of the separated-out section 51 of the busbar 5 at least in sections. In this way, the generation of the arcs 6 a, 6 band / or evaporation of conductive material of the busbar 5 as a result of the arcs and thus coating of components of the power line separators (e.g. an inner side of the housing 2) with this material can be suppressed. The partial sections 511 a, 511 bof the edge side of the section 51 covered by the separating walls 31 a, 31 bextend in particular at an angle or perpendicular to a longitudinal direction L of the power line 5.The separating walls 31 a, 31 bextend in each case along an outer circumference of the piston 3 and thus along a circular-line-like outer circumference of the end side 32 and are situated opposite one another along a diameter of the end side 32. In addition to the separating walls 31 a, 31 b, the piston 3 has two side walls 33 a, 33 b, wherein the side walls 33 a, 33 bare respectively located between the separating walls 31 a, 31 b, as viewed along the circumference of the end face 32. The side walls 33 a, 33 bprotrude beyond the separating walls 31 a, 31 b, i.e. they have a greater height (measured from the end face 32). However, this is not obligatory. It is conceivable, for example, for the height of the side walls 33 a, 33 bto correspond at least approximately to that of the separating walls 31 a, 31 b. The side walls 33 a, 33 bform a receptacle 50 for the busbar 5. the busbar 5 passes between the side walls 33 a, 33 bof the plunger 3 in the assembled state of the power line disconnection device. Accordingly, inner sides 331 a, 331 bof the side walls 33 a, 33 bextend parallel to the longitudinal direction of the busbar 5.The busbar 5 has two predetermined breaking regions in the form of depressions 53 a, 53 bin a surface 52. The depressions 53 a, 53 bare in particular shaped complementarily to the separating walls 31 a, 31 b; for example, they run in an arc shape (along a section of a circular line) analogously to the separating walls 53 a, 53 b.The busbar 5 is separated by action of the piston 3 which is set in motion in the region of the depressions 53 a, 53 band the part 51 is removed. In the configuration illustrated in FIG. 3, the piston 3 is already in contact with the busbar 5 in the starting position (which is shown in FIG. 3 ), specifically in such a way that the dividing walls 31 a, 31 bin each case engage in one of the depressions 53 a, 53 band therefore position the piston 3 relative to the busbar 5. With this arrangement of the piston 3, the best possible overlap of the edge side of the separated-out part 51 by means of the separating walls 31 a, 31 bis aimed for. In an underside 54 of the busbar 5, further predetermined breaking regions in the form of depressions 55 a, 55 bmay be provided.However, the invention is not limited to the variant shown in FIG. 3. It is also possible that the separating walls 31 a, 31 bare not in contact with the busbar 5 in the initial position of the piston 3, and the piston 3 is set in motion towards the piston 3 and impinges on the busbar 5 after activation of the motion generating device. It is also conceivable for a continuous partition wall to be present, which runs around the entire circumference of the end face 32.

Claims

Power line separating device (1) for separating a power line (5), having a separating element (3) for separating the power line (5), wherein the separating element (3) is designed and can be set in motion in such a way that it acts on the power line (5) and in the process separates a section (51) from the latter, wherein the separating element (3) has an overlapping device (31a, 31b, 33a, 33b) which overlaps at least a section (511a, 511b) of an edge side of the section (51) which is to be separated and / or separated out, characterized in that the overlapping device (31a, 31b, 33a, 33b) has two separating walls (31a, 31b) which project from an end side (32) of the separating element (3) which is to be turned towards the power line (5) and are opposite one another, wherein the partition walls (31a, 31b) each cover a partial portion (511a, 511b) of the edge side of the separated-out part (51).Power line disconnection device according to Claim 1, characterized in that the subsection (511a, 511b) of the edge side of the subsection (51), which subsection is covered by the covering device (31a, 31b, 33a, 33b), before it is disconnected from the power line (5), faces an outer subsection (52a, 52b) of the power line (5) and / or the subsection (511a, 511b) of the edge side of the subsection (51), which subsection is covered by the covering device (31a, 31b, 33a, 33b), is only produced after it is disconnected from the power line (5).The power line separating device according to claim 1 or 2, characterized in that the partition walls (31a, 31b) extend along an outer periphery of the end face (32).Power line separating device according to one of the preceding claims, characterized in that the separating walls (31a, 31b) run in an arc shape.Power line disconnection device according to one of the preceding claims, characterized in that the covering device (31a, 31b, 33a, 33b) has two side walls (33a, 33b) which are situated opposite one another and project from the end side (32) which is to be turned towards the power line (5).The power line separating device according to claim 5, characterized in that the height of the side walls (33a, 33b) is greater than the height of the partition walls (31a, 31b).Power line separating device according to one of the preceding claims, characterized in that the separating element (3) is of cylindrical design.Power line separating device according to one of the preceding claims, characterized bya movement generating device (4) for generating a movement of the separating element (3).Power line separating device according to one of the preceding claims, characterized bya housing (2) which guides the movement of the separating element (3).Power line device, comprising - a power line (5); and - a power line disconnection device (1) according to one of the preceding claims for disconnecting the power line (5).Power line device according to Claim 10, characterized in that the power line (5) has at least one predetermined breaking region (53a, 53b), wherein the separating element (3) of the power line separating device (1) in a starting position bears against the power line (5) via the covering device (31a, 31b) in the predetermined breaking region (53a, 53b).Power line device according to Claim 11, characterized in that the predetermined breaking region (53a, 53b) is formed in a manner complementary to at least part of the covering device (31a, 31b).Power line device according to Claim 11 or 12, characterized in that the predetermined breaking region (53a, 53b) comprises a depression of the power line (5), wherein the covering device (31a, 31b, 33a, 33b) of the separating element (3) is arranged at least in sections in the depression in the starting position of the separating element (3).

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