GB605016A - Improvements in or relating to electric smoothing irons - Google Patents

Abstract

605,016. Thermal switches. ELEXCEL, Ltd., and BARRIE, E. Dec. 12, 1945, No. 33573. [Class 38(v)] An electric smoothing iron with a thermostatically controlled heater has several control members 10, the operation of which sets the thermostat to different temperatures as denoted by an indication such as a label marked with the material to be worked on each control member. The members 10 comprise pushbuttons on the iron casing 12 guided through apertures in the internal iron casings 13, 14 and when depressed against the tension of a spring 25 move an arm 17 pivoted at one end to a block 15 on the sole plate. The push-buttons are of different length or steps are formed on the arm 17 which carries at its free end a switch contact 18 co-operating with a contact 19 on a spring arm 20 anchored in the block 15. A pin 21 rests in an aperture in the spring arm 20 and passes loosely through a bimetallic strip 23 mounted against the sole plate 16. The strip straightens on rise in temperature and after predetermined lost motion engages a stud 34 on the pin 21 and so opens the contacts. The pin 21 may be fixed to the bimetallic strip, movement of the spring arm 20 being then controlled by the head 22 of the pin. Each push-button is urged upwardly by a spring 26 and has two notches 27, 28 in which a cam 29 engages. The cams 29 are mounted on a rod 30 loaded by springs 31, 32 so that the cams enter the notches. Depression of a button causes clockwise rotation of all cams, thereby releasing any push-button previously depressed. When a button is fully depressed, it is held by engagement of the cam in the top notch 27. Levers may be used in place of push-buttons and may cause rotation of a cam operating on the arm 17.