OXYGEN GENERATING DEVICE

摘要

An oxygen generating device (11, 211) to which a gas mixture containing oxygen is fed, and which is operable to separate the gas mixture into oxygen rich and oxygen depleted gas components, the device (11, 211) comprising a negative temperature coefficient material (36a, 36b, 36c; 236) which is active at an elevated temperature above a minimum operating temperature, to separate the gas mixture into oxygen rich and oxygen depleted gas components, there being means (15, 28) to pass an electrical current through the device (11, 211) to produce a heating effect within the device to heat the gas mixture at least towards the minimum operating temperature wherein the device comprises a plurality of active sections (A, B, C) through each of which the gas mixture passes in turn, and the electrical current supply is connected to each of the sections (A, B, C) so that the sections electrically are connected in series.