Switch for interrupting a direct current circuit supplied by two voltage sources

Abstract

The invention relates to a switch for interrupting a circuit in which two direct voltage sources (S1, S2) and at least one load (L) are integrated and interconnected with one another, wherein the object of the invention is to interrupt the circuit quickly and effectively when required, such that after the circuit has been interrupted, potential contact between the load and any of the voltage sources must be eliminated, and in addition potential interaction between the load and any other load or circuit that can be electrically interconnected to the load must also be eliminated. To this end, in the region between the two voltage sources (S1, S2) and the load (L), a main electrical conductor (10) is bridged by an auxiliary electrical conductor (11), which is electrically connected in parallel to the voltage sources (S1, S2), to the load (L), and before activation of the switch, i.e. during normal operation of the circuit (1), is interrupted by a gap (G) and thus cannot be electrically penetrated.

Description

[0001] The present invention relates to a switch which is suitable for interrupting a direct current circuit comprising at least one load and two voltage sources which are directly connected to each other.

[0002] The present invention is based on the problem of how to quickly and effectively interrupt a circuit when required, wherein after the circuit has been interrupted, potential contact between the load and any of the described voltage sources has to be eliminated, and in addition potential interaction between the described load and any other load or circuit which can be electrically interconnected to the described load has to be eliminated.

[0003] In particular, in the field of electric vehicles, it is necessary to power the vehicle by means of two voltage sources instead of a single voltage source. That is, under this approach, even if one of the voltage sources fails, the vehicle can still be powered. However, in the field of vehicles it is always required that in emergency situations the circuit must be interrupted quickly, which is important, for example, in the event of a collision or other damage to the vehicle, which could otherwise lead to uncontrolled production of irregular circuits, short circuits and thus to a fire.

[0004] WO 2019 / 177546 discloses a switch for interrupting a direct current circuit with a single voltage source. This prior art concept provides a direct or alternating current circuit and at least one electrical load which is connected to the voltage source by means of a primary branch and a secondary branch of a main electrical conductor, wherein at least one of the branches of the main electrical conductor is connected to a backup electrical conductor, so that in each predetermined situation, i.e. when each predetermined condition is met, the branch is physically interrupted and the current which previously existed in the branch is redirected through the backup electrical conductor. The backup electrical conductor, which is in parallel to the corresponding branch of the main electrical conductor, consists of two parts which are aligned with each other, each of which is connected to the corresponding branch of the main electrical conductor and there is an electrically insulating gap between the two parts, wherein the branch of the main electrical conductor comprises a mechanically removable electrically conductive part which, in the predetermined situation, i.e. when each predetermined condition is met, can be removed from the rest of the branch by means of a corresponding mechanical impact and can be irreversibly moved into the gap between the two parts of the backup conductor, whereby the backup electrical conductor is bridged and electrically conductive. In addition to the electrical conductor, a pyrotechnic actuator is provided which is adjusted to be triggered in the predetermined situation when each predetermined condition is met, and is arranged adjacent to the removable part of the weakened branch of the main electrical conductor, so that the part can be mechanically removed from the branch by means of the pyrotechnic actuator and moved into the gap between the two parts of the backup conductor. This concept can be successfully used in circuits with a single voltage source, but not in circuits integrated with two voltage sources. Furthermore, US 2019 / 0283626 A1 discloses a HV energy storage device.

[0005] The invention relates to a switch for interrupting a direct current circuit integrated with two direct voltage sources, which are in series with each other and both electrically connected to at least one electrical load via a main electrical conductor.

[0006] According to the invention, the aforementioned technical problem is solved in such a way that the main electrical conductor is bridged in the area between the voltage source and the load by an auxiliary electrical conductor, which is electrically connected in parallel to the voltage source, the load and, before the activation of the switch, i.e. during the normal operation of the circuit, is interrupted by a gap and thus cannot be electrically penetrated. On the other hand, in the area between the two connection points separated from each other, an electrically conductive branch integrated with an electric fuse having a fuse element is connected in parallel to the main electrical conductor. In the intermediate area between the connection points, the main electrical conductor has a removable part, which can be removed from the main electrical conductor under each predetermined condition and irreversibly displaced into the gap in the auxiliary electrical conductor, so that the auxiliary electrical conductor becomes electrically conductive, and the main electrical conductor becomes electrically non-penetrable when the part is removed from the main electrical conductor.

[0007] In a preferred embodiment of the invention, the part of the main electrical conductor can be moved into the gap in the auxiliary electrical conductor by a pyro-switch, which is preferably activated by a sensor. The sensor is generally any sensor suitable for activating the pyro-switch, more preferably an acceleration detection sensor.

[0008] The invention will be further explained on the basis of the embodiments presented in the accompanying drawings, in which:

[0009] Figure 1 A switch according to the invention is schematically shown, which is adapted to interrupt a direct current circuit and the corresponding load during the normal energization of the circuit by two voltage sources;

[0010] Figure 2 A switch is shown when the pyro-switch is activated on the basis of a signal received from the sensor and the circuit is interrupted Figure 1 ;

[0011] Figure 3 A switch is shown when the main circuit is interrupted and another circuit is established by the auxiliary electrical conductor and the fuse Figure 1 ; and

[0012] Figure 4 A switch is shown in another state Figure 1 , in which the fuse element of the fuse is also interrupted in the case of the interruption of the main circuit and the establishment of another circuit by the auxiliary electrical conductor and the fuse.

[0013] The switch according to the application is suitable for interrupting a direct current circuit 1 in which two direct voltage sources S1, S2 are integrated, the voltage sources being connected in series with each other and both being electrically connected to at least one electrical load L via a main electrical conductor 10.

[0014] The main electrical conductor 10 is bridged in the region between the voltage sources S1, S2 and the load L by an auxiliary electrical conductor 11 which is electrically connected in parallel to the voltage sources S1, S2, the load L and, before activation of the switch, i.e. during normal operation of the circuit 1, is interrupted by a gap G and thus cannot be electrically penetrated.

[0015] In the region 100 between the two voltage sources S1 and S2, two connection points 100', 100'' are separated from each other at which an electrically conductive branch 12 of an electric fuse 2 is connected in parallel to the main electrical conductor 10, the electric fuse 2 having a fuse element 21.

[0016] In an intermediate region 1000 between the connection points 100', 100'', the main electrical conductor 10 has a removable component 10' which can be removed from the main electrical conductor 10 under respective predetermined conditions and is irreversibly displaced into the gap G in the auxiliary electrical conductor 11, so that the auxiliary electrical conductor 11 becomes electrically conductive and, when the component 10' is removed from the main electrical conductor 10, the main electrical conductor 10 becomes electrically non-penetrable. The removable component 10' and the region of the auxiliary electrical conductor 11 adjacent to the gap G can optionally be designed in the manner used in the previously cited prior art (WO 2019 / 177546).

[0017] In the illustrated embodiment, the component 10' of the main electrical conductor 10 can be moved into the gap G in the auxiliary electrical conductor 11 by means of a flame switch 3 which is activated by a sensor 4 which is suitable for detecting acceleration.

[0018] Under normal operation of the circuit 1, the load L is integrated into the circuit via the main electrical conductor which is supplied with electrical power by the two voltage sources S1, S2. Since the electrical resistance of the fuse 2 is substantially higher than the electrical resistance of the conductors 10, 11, no or at least virtually no current flows through the electrically conductive branch 12 in this mode of operation.

[0019] In case of an emergency, for example due to a collision of the electric vehicle, etc., i.e. as soon as the predetermined conditions are met, the sensor 4 activates the said flame switch 3, which causes the part 10' to be removed from the main electrical conductor 10 and displaced into the gap G in the auxiliary electrical conductor 11. Thus, on the one hand the main electrical conductor 10 is interrupted at its intermediate region 1000 between the two voltage sources S1, S2, and on the other hand the load L is integrated into a short circuit established by the auxiliary electrical conductor 11, the gap G in the auxiliary electrical conductor 11 being bridged and thus conductive by the said part 10' of the main electrical conductor 10. In this case, current can still only flow through the conductive branch 12, resulting on the one hand in a discharge of the load L and possibly also of the voltage sources and other loads connected in some way with the load L, and on the other hand in the heating and melting of the fuse element 21 in the fuse 2, in which case the conductive branch 12 is interrupted and cannot be electrically penetrated. Here, the discharged load L is integrated into its own electrical circuit via the auxiliary electrical conductor 11, in effect causing a short circuit, while the voltage sources S1, S2 are still integrated in a separate electrical circuit via the auxiliary electrical conductor 11, but at the intermediate region between the voltage sources S1, S2, which is physically interrupted and clearly cannot be electrically penetrated. The person skilled in the art will understand that the length of the part 10' should be sufficient to prevent an electric arc from being created when the said part 10' is removed from the main electrical conductor 10.

Claims

1. A switch for interrupting a direct current circuit (1), wherein Integrated in the circuit (1) are two DC voltage sources (S1, S2) connected in series with each other and both electrically connected to at least one electrical load (L) via a main electrical conductor (10), wherein The main electrical conductor (10) is bridged in the area between the voltage sources (S1, S2) and the load (L) by an auxiliary electrical conductor (11) which is electrically connected in parallel to the voltage sources (S1, S2), the load (L) and, before the activation of the switch, i.e. during normal operation of the circuit (1), is interrupted by a gap (G) and thus cannot be electrically penetrated, characterized in that Integrated at two connection points (100', 100'') separate from each other in the area (100) between the voltage sources (S1, S2) are electrically conductive branches (12) of an electrical fuse (2) connected in parallel on the one hand to the load (L) and on the other hand to the main electrical conductor (10), the electrical fuse (2) having a fuse element (21), while in the intermediate area (1000) between the connection points (100', 100'') the main electrical conductor (10) has a removable part (10') which can be removed from the main electrical conductor (10) under respective predetermined conditions and irreversibly displaced into the gap (G) in the auxiliary electrical conductor (11), so that the auxiliary electrical conductor (11) becomes electrically conductive and the main electrical conductor (10) becomes electrically non-penetrable upon removal of the removable part (10') from the main electrical conductor (10).

2. The switch of claim 1, wherein The part (10') of the main electrical conductor (10) can be moved into the gap (G) in the auxiliary electrical conductor (11) by means of a flame switch (3).

3. The switch of claim 2, wherein The flame switch (3) is activated by means of a sensor (4).

4. The switch of claim 3, wherein The sensor (4) for activating the flame switch (3) is an acceleration detection sensor.

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