| 摘要 |
439,457. Non-contact-making relays. HEIL, O., 21, Jagowstrasse, Grunewald, Berlin. March 4, 1935, No. 6815. Convention date, March 2, 1934. [Class 40 (iv)] The electrical resistance of a semi-conductor 3 forming one electrode of a condenser is varied by alternating potential applied across the condenser, thus giving rise to variations in a local circuit through the semi-conductor and a battery 4. The semi-conductor 3 is in the form of a thin layer placed between metal electrodes 1, 2, and is separated from the other or control electrode 6 of the condenser by a thin layer of insulation of high dielectric constant. Air or vacuum insulation may be employed. Control electrodes may be disposed on both sides of the semi-conductor, and the same or different alternating potentials may be applied to them. The semi-conductors comprise tellurium, iodine, cuprous oxide, vanadium pentoxide and other substances having a negative temperature coefficient of resistance, and substances which exhibit the Hall effect with a positive coefficient. |
