Switching Device Having an Actuation Unit, On-Board Electrical System and Motor Vehicle

Abstract

A switching device for an on-board electrical system of an electrically driven motor vehicle includes an electromechanical switch which is designed to connect and interrupt a supply line of the on-board electrical system. The electromechanical switch has: a stationary first switching contact, a movable second switching contact, and an actuation unit which has a mechanical force-transmitting element and a drive element. In order to switch from an open switching state to a closed switching state of the electromechanical switch, the drive element moves the transmitting element along a movement path, and the force-transmitting element moved along the movement path acts mechanically on the second switching contact and moves the second switching contact toward the first switching contact. In order to maintain the closed switching state of the electromechanical switch, the force-transmitting element applies, at the end of the movement path, a pressing force to the second switching contact for pressing against the first switching contact, without further driving by way of the drive element.

Claims

1.-10. (canceled)

11. A switching device for an on-board electrical system of an electrically drivable motor vehicle, comprising: an electromechanical switch which is configured to connect and interrupt a supply line of the on-board electrical system, wherein the electromechanical switch comprises: a stationary first switching contact, a movable second switching contact, and an actuation unit which has a mechanical force-transmitting element and a drive element, wherein to transfer from an open switching state to a closed switching state of the electromechanical switch, the drive element is configured to move the force-transmitting element along a movement path, and the force-transmitting element moved along the movement path is configured to act mechanically on the second switching contact and to move the second switching contact toward the first switching contact, and to maintain the closed switching state of the electromechanical switch, the force-transmitting element is configured to apply, at an end of the movement path, a pressing force to the second switching contact for pressing against the first switching contact, without further driving via the drive element.

12. The switching device according to claim 11, further comprising: a spring element, wherein to transfer the electromechanical switch from the closed switching state to the open switching state, the drive element is configured to move the force-transmitting element counter to the movement path in order to remove the pressing force from the second switching contact, wherein the second switching contact is connected to the spring element which is configured to move the second switching contact away from the first switching contact during the movement of the force-transmitting element against the movement path and to hold the second switching contact in the moved-away state to maintain the open switching state.

13. The switching device according to claim 12, wherein the spring element is an elastic busbar which is electrically and mechanically connected to the second switching contact.

14. The switching device according to claim 11, wherein the force-transmitting element has a threaded spindle which is linearly displaceable along the movement path by a drive element.

15. The switching device according to claim 14, wherein the threaded spindle is oriented substantially perpendicular to a surface of the second switching contact, so that the threaded spindle moved along the movement path is configured to act substantially perpendicular to the surface and to push the second switching contact substantially parallel to an orientation direction of the movement path in the direction of the first switching contact.

16. The switching device according to claim 11, wherein the force-transmitting element has a push rod which is displaceable by the drive element.

17. The switching device according to claim 16, wherein the push rod is oriented obliquely to a surface of the second switching contact, so that the push rod moved along the movement path is configured to slide over the surface of the second switching contact and to push the second switching contact obliquely to an orientation direction of the movement path in the direction of the first switching contact.

18. The switching device according to claim 11, further comprising: a pyrotechnical disconnection unit which is configured to interrupt the supply line in the event of a fault.

19. An on-board electrical system for a motor vehicle, comprising: at least two on-board electrical system components; at least one supply line electrically connecting the at least two on-board electrical system components; and at least one switching device comprising an electromechanical switch which is configured to connect and interrupt the at least one supply line, wherein the electromechanical switch comprises: a stationary first switching contact, a movable second switching contact, and an actuation unit which has a mechanical force-transmitting element and a drive element, wherein to transfer from an open switching state to a closed switching state of the electromechanical switch, the drive element is configured to move the force-transmitting element along a movement path, and the force-transmitting element moved along the movement path is configured to act mechanically on the second switching contact and to move the second switching contact toward the first switching contact, and to maintain the closed switching state of the electromechanical switch, the force-transmitting element is configured to apply, at an end of the movement path, a pressing force to the second switching contact for pressing against the first switching contact, without further driving via the drive element.

20. An electrically drivable motor vehicle comprising an on-board electrical system according to claim 19.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0019] FIG. 1 is a schematic representation of a first embodiment of a switching device for an on-board electrical system; and

[0020] FIG. 2 is a schematic representation of a second embodiment of the switching device.

[0021] In the figures, like and functionally like elements have been provided with the same reference signs.

DETAILED DESCRIPTION OF THE DRAWINGS

[0022] FIG. 1 and FIG. 2 show different embodiments of a switching device 1 for an on-board electrical system of an electrified motor vehicle. The switching device 1 is configured to switch off a supply line of the on-board electrical system away from a fault and to interrupt it in the event of a fault. For this purpose, the switching device 1 has an electromechanical switch 2, which has a first, stationary switching contact 3, a second switching contact 4, which can move with respect to the first switching contact 3, and an actuation unit 5. The second switching contact 4 is electrically and mechanically connected here to a spring element 6 in the form of a spring-elastic busbar 7 and is thus spring-elastically mounted. The busbar 7 is in turn electrically connected to the supply line of the on-board electrical system.

[0023] To transfer the switch 2 from the open switching state shown here to a closed switching state in which the switch 2 carries a current and connects the supply line, the actuation unit 5 moves the second switching contact 4 to the first switching contact 3 and exerts a pressing force on the second switching contact 4. This pressing force presses or pushes the second switching contact 4 against the first switching contact 3, so that the switch 2 has a particularly low contact resistance in the closed switching state. For this purpose, the actuation unit 5 has a force-transmitting element 8 which can be driven by a drive element, not shown here. By driving the force-transmitting element 8, the latter is displaceable or movable along a movement path 9. The force-transmitting element 8 transmits its movement against a spring force of the spring element 6 to the second switching contact 4, which is then moved in the direction of the first switching contact 3 until the switching contacts 3, 4 touch each other. This pressed-on state of the switching contacts 3, 4 is maintained by the force-transmitting element 8 even when the drive element no longer drives the force-transmitting element 8.

[0024] During the closed state of the switch 2, the pressing force exceeds the spring force and the second switching contact 4 is pressed against the first switching contact 3. To open the switch 2, the switching contacts 3, 4 are released or separated from each other again. To release the switching contacts 3, 4, the force-transmitting element 8 is again moved against the movement path 9. As a result, the spring force exceeds the pressing force of the force-transmitting element 8 on the second switching contact 4, so that the latter is removed from the first switching contact 3 by the spring element 6.

[0025] In the embodiment of the switching device 1 according to FIG. 1, the force-transmitting element 8 has a threaded spindle 10 and a spindle nut 11. The threaded spindle 10 is set into a rotary lifting motion 12 by the drive element, for example an electric motor, by which the threaded spindle 10 and thus the second switching contact 4 can be moved up and down. A direction of orientation of the movement path 9 is oriented here parallel to a direction of movement of the second switching contact 4. Thus, to close the switch 2, the threaded spindle 10 is moved upward here. As a result, the threaded spindle 10 pushes the second switching contact 4 upward in the direction of the first switching contact 3.

[0026] In the embodiment of the switching device 1 according to FIG. 2, the force-transmitting element 8 has a push rod 13, which is pushed over a surface 14 of the second switching contact 4, here to the left. As a result, the second switching contact 4 is pressed downward here in the direction of the first switching contact 3. The direction of orientation of the movement path 9 is here oriented obliquely to the direction of movement of the second switching contact 4. To open the switch 2, the push rod 13 is shifted against the movement path 9, in this case to the right. This allows the second switching contact 4 to release from the first switching contact 3 again.