GB397501A - Improvements in and relating to fabric ironing appliances - Google Patents

Abstract

397,501. Thermal switches. BRITISH LAUNDERERS' RESEARCH ASSOCIATION, 17, Lancaster Gate, and HAMPSON, R. E. V., The Laboratory, Hill View Gardens, Hendon, both in London. Feb. 19, 1932, No. 4907. [Class 38 (v).] The temperature of an electric hand-iron is regulated by means of a thermostat operating by the different expansions of the iron itself and a length or lengths of material of lower coefficient of expansion. In Fig. 1, a rod 3 of a material having a small coefficient of thermal expansion compared with that of the body 1 of the iron is adjustably secured at one end of an axial hole 2 bored in the sole of the iron and is free at its other end where it engages one arm of a bell-crank lever, of which the other arm 8 carries a contact 12 which coacts with a contact 13 mounted on a resilient arm 14. As shown the contacts 12, 13 are arranged to close as the iron heats up, but they may be arranged to open instead of closing at a predetermined temperature. In Fig. 5, a pair of rods 33, 34 are engaged in recesses at the ends of a longitudinal bore in the sole plate, one end being plugged at 31 to permit adjustment of the initial position of the 'rods. The inner ends of the rods freely engage one another and are acted on by a plunger 36 which is pressed down by a spring 37 and is provided with a cotter pin 48 which, as the iron heats up and the rods assume a straight line position, presses on a spring arm 38 carrying a contact 40 which normally engages a stationary contact 41. Means may be provided for preventing arcing at the contacts when the circuits are broken. Such means may be mounted within the handle.