ATBECHDEDKESFRGBGRITLILUNLSEMCPTIE......FI......................................JDIM360 (Ver 1.5 21 Nov 2005) - 1100000/00831506EUROPEAN PATENT APPLICATIONA319981021EP97307168.119970916enenen9619676 19960920GB19981021199843199803251998136 6H 01H 37/48 A 6H 01H 37/76 BdeThermostatenThermostatfrThermostat1Sunvic Controls Limited02391150AH/MP 5643127Bellshill RoadUddingston, Glasgow G71 6NP, ScotlandGBBurgess, Alan, c/o Sunvic Controls LtdBellshill Road, UddingstonGlasgow G71 6NP, ScotlandGBHay, Robert, c/o Sunvic Control LtdBellshill Road, UddingstonGlasgow G71 6NP, ScotlandGBAllan, Susan, c/o Sunvic Controls LtdBellshill Road, UddingstonGlasgow G71 6NP, ScotlandGBHamilton, Alistairet al00074651Mewburn Ellis, York House, 23 KingswayLondon WC2B 6HPGBATBECHDEDKESFIFRGBGRIEITLILUMCNLPTSE19981021199843

A thermostat comprises a tube (10) with a switch assembly (12) mounted at a first end of the tube. A rod (14) extends within the tube and is secured to it adjacent its second end (16). The rod (14) has a coefficient of thermal expansion different from that of the tube (10) and is operatively coupled to the switch assembly (12) so as to cause the switch assembly (12) to change state in reaction to a change of temperature of the tube (10). There is carried on the rod (14) a first supporting member (42) formed from a material of a high melting point and a second supporting member (44) formed from a material with a melting point below that temperature which would be dangerous if exceeded in use. A spring (50) is trapped in compression between the first and second supporting members (42,44). An actuating assembly (60,62,64)) is operable under the action of the spring (50) on its release in the event of the second supporting member (44) melting, to cause the switch assembly (12) to change state so as to prevent further heating.