| 摘要 |
<p>A unipolar electric contact comprises two semi - contacts arranged for embedding in the sides of glass - chamber frames. A first semi -contact includes a permanent magnet with a central hole through which to pass the shank of a first non-magnetic metal mushroom with a flattened circular head, held against the magnet in front of it for protection against shocks received from the head of a second paramagnetic metal mushroom forming part of the second semi - contact. The first metal mushroom is fixed while the second one can move, by magnetic effect, the shank of it being inside a helical spring placed in an eccentric hole that passes longitudinally through a non-magnetic metal bushing. The spring is compressed by the mobile mushroom moving outwards. As the frame is open the mobile mushroom is brought back by the returning action of the spring. The shank of the fixed mushroom is connected to an electric wire. The bushing is connected with a second fixed wire held in electrical continuity with the shank of the mobile mushroom through the bushing.</p> |
