GB459475A - Improvements in controlling and regulating the heating elements of electric kettles and like boiling or cooking apparatus - Google Patents

Abstract

459,475. Automatic control systems. WILKINSON, G., 23, Otley Road, Harrogate. May 19, 1936, No. 14133. [Class 38 (iv)] [See also Groups XXXVI and XXXVII] Temperature.-Control arrangement for the heating elements of a kettle &c. comprising a pair of elements in series with a thermostatic switch short-circuiting one of them until the desired temperature is reached, wherein the thermostatic switch is mounted within the casing protecting the circuit terminals. The switch element comprises a base b, Fig. 1, mounted on the kettle carrying contacts c, c<1> and d, d<1> to which the main and auxiliary heaters are connected. Contacts c<1> and dl are connected together and contacts c, d extended to form plugs to engage a socket s, Fig. 2, so that the heaters are in series across the supply. Bridging the contacts d, d<1>, and thus short-circuiting the auxiliary heater, is a pivoted contact arm f which is operated by a bimetallic strip k to insert the auxiliary heater in circuit when the required temperature is reached. A ring-shaped contact i is used to allow it to be turned round to give a fresh contact face. The bimetallic strip has an adjustable fixing l to enable the temperature setting to be adjusted. The bimetallic strip may be put out of action by a cam p pivoted to the socket s and having an operating handle p2. In a modification, the expansion of a liquidfilled capsule is used to operate the switch.