| 摘要 |
<p>A moving first electrical contact arrangement (K1) has a switching contact (P4) and a U-shaped arcing horn (R1) on the end face. A stationary second electrical contact arrangement (K2) has a switching contact (P1) and a U-shaped electrical conductor loop (R2) on the end face. The electrical conductor loop (R2) is composed in its U-shaped part, of a bimetallic strip, composed of steel (2) on the inside and copper (3) on the outside; two mutually opposite switching contacts (P2, P3) are provided adjacent to this, and an arcing horn (3') is provided on the end face. When the electrical switch is closed, the first electrical contact arrangement (K1) is moved to the left in the opposite direction to an arrow (5), so that all four switching contacts (P1)-(P4) make a pressure contact with one another. When the electrical switch is opened, the contact pairs (P1, P2) are disconnected first, as a result of which a current (4) is commutated from them into the electrical conductor loop (R2) as is shown by a dashed line. Once the stress on the electrical conductor loop (R2) has been relieved, the contact pair (P3, P4) is also disconnected, so that an arc (6) is struck, which is driven onto the arcing horns (3', R1) by the asymmetric current routing in the electrical conductor loop (R2). The arc is thus quickly driven away from its original contact point and, in the process, is increasingly asymmetrically blown magnetically, so that its burning voltage rapidly increases. This simple contact structure, which can be produced economically, ensures a low rate of wear.</p> |
