Electric fuse element, and method for operating an electric fuse element

Abstract

Electrical fuse element 12 comprising a switchable load path 22 and a switchable fuse path 36, wherein the load path 22 and the fuse path 36 are short-circuited with their respective inputs 14. The load path 22 and the fuse path 36 are in mechanical connection with each other in such a way that an electrical opening of the load path 22 causes an electrical closing of the fuse path 36 and that a melting fuse 38 arranged in the fuse path 36 is triggered at the moment of closing of the fuse path 36.

Claims

1. Electrical fuse element comprising, a switchable load path having a separation point; and a switchable fuse path, wherein the load path and the fuse path with their respective inputs are short-circuited with each other, wherein the load path and the fuse path are in mechanical connection with one another in such a way that a mechanically driven disconnecting element is arranged to cause an electrical opening of the load path by separating the load path at the separation point and simultaneously causing an electrical closing of the fuse path and a fuse arranged in the fuse path so as to trigger at the moment of closing of the fuse path, wherein the disconnecting element has a disconnection slide which is accelerated by a drive in the direction of the separation point of the load path, the movement of the disconnection slide causing the fuse path to close.

2. Fuse element of claim 1, wherein the disconnection slide is formed as a piston displaceable in a housing, the piston accelerating a flowable medium arranged at least between the separation point and the disconnection slide in the direction of the separation point.

3. Fuse element of claim 1, wherein the disconnection slide has a conductor, the conductor being movable in-between two connections of the fuse path by the drive.

4. Electrical fuse element comprising, a switchable load path having a separation point; and a switchable fuse path, wherein the load path and the fuse path with their respective inputs are short-circuited with each other, wherein the load path and the fuse path are in mechanical connection with one another in such a way that a mechanically driven disconnecting element is arranged to cause an electrical opening of the load path by separating the load path at the separation point and simultaneously causing an electrical closing of the fuse path and a fuse arranged in the fuse path so as to trigger at the moment of closing of the fuse path, wherein the disconnecting element comprises a flowable medium, the flowable medium being accelerated by a drive in the direction of the separation point and a pressure acting thereby on the separation point separating the separation point.

5. Fuse element of claim 3, wherein the conductor short-circuits the connections of the fuse path after activation of the drive.

6. Fuse element of claim 4, wherein the flowable medium is liquid, pasty, foamy, gel-like or granular.

7. Fuse element of claim 4, wherein the flowable medium has electrically insulating properties and/or has arc-quenching properties.

8. Fuse element of claim 4, wherein the flowable medium is a free-flowing bulk material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) In the following, the subject is explained in more detail by means of a drawing showing embodiments. In the drawing show:

(2) FIG. 1 an equivalent circuit diagram of a vehicle electrical system with a fuse element according to the subject matter;

(3) FIG. 2a a fuse element in normal condition according to the subject matter;

(4) FIG. 2b a fuse element during activation;

(5) FIG. 2c a fuse element in the tripped state.

DETAILED DESCRIPTION OF SPECIFIC EMBODIMENTS

(6) FIG. 1 shows an equivalent circuit diagram of an on-board network 2 of a motor vehicle. A high-voltage battery 4 is shown as an example. The high-voltage battery 4 can in particular be a battery of a vehicle drive train. The B+ pole 4a of battery 4 is connected via a series resistor 6 and an “ignition switch” 8 to a drive train 10 as a load. During operation the switch 8 is closed.

(7) The B− pole 4b is connected to the load 10 via the fuse element 12. The fuse element 12 has an input terminal 14 as well as a first output terminal 16 and a second output terminal 18. The load path is formed across the input terminal 14 and the output terminal 16. The fuse path is formed across the input terminal 14 and the output terminal 18. The output terminal 16 is connected to load 10 and the output terminal 18 is connected to the B+ pole 4a.

(8) The fuse element 12 is shown in detail in FIG. 2a. Load path 20 connects input terminal 14 with output terminal 16. Load path 20 has a disconnecting element 22, on which a predetermined separation point 24 is located. The disconnecting element 22 closes a housing 26 in which a flowable medium 28 is arranged.

(9) The housing 26 is formed in the manner of a channel in which a disconnection slide 30 is arranged. The disconnection slide 30 can be moved in direction 32. The disconnection slide 30 is formed in two parts from an insulator 30a and a conductor 30b.

(10) In the channel, in front of the disconnection slide 30, a drive 34 is arranged, which is formed as a pyrotechnic drive.

(11) When the drive 34 is activated, the disconnection slide 30 is accelerated in direction 32. This causes the flowable medium 28 to exert a pressure on the separation point 24 in such a way that it bursts. This is described below.

(12) The safety path 36 is formed across the input terminal 14 and the output terminal 18. The disconnection slide 30 forms an electrical separation along the fuse path 36 by the insulator 30a. A melting fuse 38 is located in the fuse path 36.

(13) FIG. 2b shows the fuse element 12 at the moment of activation. The drive 34 was activated by an external signal, for example an airbag control signal or similar. This causes a force to act on the disconnection slide 30 so that it is accelerated in the direction of 32. This causes the medium 28 to exert such a pressure on the disconnecting element 22, so that the predetermined separation point 24 bursts.

(14) At the same time, the movement of the disconnection slide 30 in the housing 26 causes the conductor 30b to close the fuse path 36. This closing of the fuse path 36 leads to a short circuit between the input terminal 14 and the output terminal 18 and thus, as can be seen in FIG. 1, between the B+ pole 4a and the B− pole 4b of battery 4.

(15) This short-circuit leads to a commutation of any current still flowing via the disconnecting element 22, for example via an arc, to fuse path 36. In fuse path 36, melting fuse 38 is activated via the commutated current. The melting fuse 38 melts and also disconnects the fuse path 36.

(16) This leads to the situation in FIG. 2c, where it can be seen that both load path 20 and fuse path 36 are currentless. The load 10 is thus completely separated from battery 4.

REFERENCE SIGNS

(17) 2 Vehicle electrical system 4 High voltage battery 4a B+ pole 4b B− pole 6 Resistance 8 Switches 10 Load 12 Fuse element 14 Input terminal 16, 18 Output terminal 20 Load path 22 Disconnecting element 24 Separation point 26 Housing 28 Medium 30 Disconnection slide 30a Insulator 30b Conductor 32 Direction 34 Drive 36 Fuse path 38 Melting fuse