Abstract
The invention relates to a device for interrupting or closing an electrical circuit. The invention further relates to a method of interrupting or closing an electrical circuit. An inventive circuit interruption device for interrupting an electrical circuit contains a contact piece comprising a ceramic material.
Claims
1. Circuit interruption device for interrupting an electrical circuit, comprising a contact piece, the contact piece comprising a ceramic material, wherein the ceramic material is doped.
2. Circuit interruption device according to claim 1, wherein the contact piece contains a plurality of sub-pieces, the sub-pieces comprising ceramic material of different conductivities.
3. Circuit interruption device according to claim 1, wherein the contact piece comprises a coating with a ceramic material.
4. Circuit interruption device according to claim 1, wherein the contact piece is made of the ceramic material.
5. Circuit interruption device according to claim 1, wherein the circuit interruption device has a plurality of contact pieces.
6. Circuit interruption device according to claim 5, wherein the plurality of contact pieces is arranged in pairs, in each pair of contact pieces one movable contact piece being arranged movably with respect to a second contact piece.
7. Circuit interruption device according to claim 6, wherein the second contact piece is embodied as a fixed contact piece.
8. Circuit interruption device according to claim 1, wherein the circuit interruption device is adapted to provide the current to be switched with a current path over the ceramic material at each stage of the interruption process.
9. Circuit interruption device according to claim 8, wherein the current path over the ceramic material is dimensioned such that the starting criteria for arc initiation are not fulfilled.
10. Method of interrupting an electrical circuit, wherein a circuit interruption device according to claim 1 is employed, with a plurality of contact pieces cooperating.
11. Method according to claim 10, wherein during the interruption process, various sub-pieces of a contact piece are introduced into the circuit.
12. Method according to claim 11, wherein the various sub-pieces of a contact piece are introduced into the circuit by shifting of a contact piece with respect to another contact piece.
Description
[0030] Other advantages, particularities and advantageous further developments of the invention will become clear from the dependent Claims and the following presentation of preferred examples of embodiment by means of the figures.
[0031] In the figures:
[0032] FIG. 1 shows a schematic structure of a circuit interruption device according to the invention with a stepwise, quasi-continuous change in conductivity;
[0033] FIG. 2 shows a schematic structure of a circuit interruption device according to the invention with a continuous change in conductivity;
[0034] FIG. 3 shows the basic interruption process with the circuit interruption device according to the invention with the movable contact piece in a first position;
[0035] FIG. 4 shows the basic interruption process with the circuit interruption device according to the invention with the movable contact piece in a second position;
[0036] FIG. 5 shows the basic interruption process with the circuit interruption device according to the invention with the movable contact piece in a third position;
[0037] FIG. 6 shows the basic interruption process with the circuit interruption device according to the invention with the movable contact piece in an off position.
[0038] FIG. 1 shows a schematic structure of a circuit interruption device 100 according to the invention with a stepwise, quasi-continuous change in conductivity. The circuit interruption device 100 has a fixed contact piece 150 and a movable contact piece 110. The contact pieces are connected to the electrical circuit to be interrupted via connections 101. The fixed contact piece 150 shown in FIG. 1 has a series of different resistance stages in the form of sub-pieces 151, 152, 153, 154, 155, the conductivity increasing from the first sub-piece 151 via the additional sub-pieces 152, 153 and 154 up to the last sub-piece 155. The sub-pieces 151, 152, 153, 154 are coated with a ceramic material which has different stages of doping such that conductivity varies in the manner described above. The fifth sub-piece 155 can be non-coated so that in the position in which the movable contact piece 110 contacts the fifth sub-piece 155, a current path is available which has full conductivity. For example, the movable contact piece 110 and the fifth sub-piece 155 can consist of a metal with metallic surface, in particular a metal with good electric conductivity, such as e.g. copper or a copper alloy. By shifting the movable contact piece 110 over the sub-pieces 155, 154, 153, 152, 151, the current to be switched is offered current paths with decreasing electrical resistance. The sub-pieces 151, 152, 153, 154, 155 can be small such that the electrical resistance decreases quasi-continuously, in particular not abruptly.
[0039] FIG. 2 shows a schematic structure of a circuit interruption device 100 according to the invention with continuous change in conductivity. The fixed contact piece 150 has a continuous shape of ceramic material which sheathes the fixed contact piece. By sliding of the movable contact piece 110 over this continuous shape of the ceramic material, a continuous rise in electrical resistance is allowed. Possible courses can be a linear, a square or an exponential rise in electrical conductivity from the on position E to the off position A.
[0040] FIG. 3 shows the basic interruption process with the circuit interruption device 100 according to the invention with the movable contact piece 110 in a first position. In the on position E of the movable contact piece 110 on the fixed contact piece 150, which is shown in FIG. 3, the circuit connected by connections 101 is closed. An electrical current I flows via the movable contact piece 110 through the fixed contact piece 150.
[0041] FIG. 4 shows the basic interruption process with the circuit interruption device 100 according to the invention with the movable contact piece 110 in a second position. During the interruption process, the movable contact piece is shifted to the left on the fixed contact piece 150 in the direction of the off position A and the ceramic material is introduced into the electrical circuit, increasing electrical resistance and decreasing current intensity I which is represented by a weaker intensity of the arrow I.
[0042] FIG. 5 shows the basic interruption process with the circuit interruption device 100 according to the invention with the movable contact piece 110 in a third position. The farther the movable contact piece 110 is shifted to the left into the off position A, the more ceramic material, possibly with different dopings, is introduced into the circuit and the stronger the electrical resistance of the circuit interruption device 100 becomes.
[0043] FIG. 6 shows the basic interruption process with the circuit interruption device 100 according to the invention with the movable contact piece 110 in an off position A. At the end of shifting of the movable contact piece 110 on the fixed contact piece 150, it is possible to mechanically separate the movable contact piece 110 from the fixed contact piece 150 and thus to galvanically separate the circuit without creation of an arc.
[0044] The embodiments shown here are only examples of the present invention and are therefore not to be intended as limiting. Alternative embodiments considered by the person skilled in the art are equally comprised by the scope of protection of the present invention.
LIST OF REFERENCE NUMBERS
[0045] 100 circuit interruption device [0046] 101 connection to circuit [0047] 110 movable contact piece [0048] 150 fixed contact piece [0049] 151 first sub-piece of fixed contact piece [0050] 152 second sub-piece of fixed contact piece [0051] 153 third sub-piece of fixed contact piece [0052] 154 fourth sub-piece of fixed contact piece [0053] 155 fifth sub-piece of fixed contact piece [0054] E on position [0055] A off position [0056] I current
