Method of detection in an alarm system

Claim 1

An improved detection arrangement for sensing an elevation in temperature of a body from a temperature T1 to a relatively higher temperature T2 and for generating an indication of the elevation in temperature to the temperature T2 comprising: a support body whose temperature is subject to rise; a material positioned on said support body in close contact with said body whereby the temperature of said material will vary substantially in accordance with variations in the temperature of said body, said material being independent of the structure of said body and adapted to emit into the atmosphere above the body at a predetermined elevated temperature T2 a gaseous phase substance whose existence can be detected by ionization detection means; ionization detection means positioned near said support body for detecting an emission into the atmosphere about the body from said material; means responsive to said ionization detector for providing an indication of the detection of said substance, said support body comprising a member of an energized apparatus, a source of energy, means for applying energy from said source to said apparatus, said means for applying energY adapted to be responsive to the electrical indication of said ionization detector for automatically interrupting the application of energy to said apparatus upon an occurrence of said indication.