GB512958A - Improvements relating to electrically heated utensils - Google Patents

Abstract

512,958. Automatic control systems. PREMIER ELECTRIC HEATERS, Ltd., COLLINS, G. H., and TAYLOR, H. T. March 23, 1938, No. 8975. [Class 38 (iv)] [Also in Group XXXVII] Temperature.-In a thermostatically-controlled electrically-heated utensil such as an iron or kettle, a plate 10 at the base of the vessel carries a bracket 12 on which is mounted an insulating block 1'5 in which are moulded spring strips 18, 19, 20 which carry contacts 29, 30, 31 respectively which normally engage each other with a slight pressure so that a heating element 23 is in circuit and a heating element 22 is cut out. To the plate 10 is fixed a bimetal strip 40 which carries a U-shaped member 41 in an insulating block on which are threaded screws 44, 45. When the utensil is heated the bimetallic strip straightens and first the screw 44 engages and moves up a stiff extension of the strip 18 to separate contacts 29, 30 and connect heating elements 22, 23 in series, and then the screw 45 engages and moves up a stiff extension of the strip 19 to separate contacts 30, 31 and completely open the heating circuit. A cam 34 on a spindle 33 is manually operated to engage the lowest contact 31 and vary the initial position of all three springs so altering the operating temperatures. An alternative construction is described in the Provisional Specification in which a stud carried by the bimetallic strip passes from above through the top spring strip 18 which it engages from below by a head, and the spring strip 18 has a similar stud to engage the strip 19. The adjusting cam may be replaced by a face cam or screw.