GB1361668A - Domestic electric oven - Google Patents

Abstract

1361668 Oven-door locks ETABS EUGENE SCHOLTES 28 Oct 1971 [30 Oct 1970] 50088/ 71 Heading E2A . An electric kitchen oven is designed for permitting the cleaning of its inner walls by the burning-off of the fatty or other deposits form thereon and comprises an electro-mechanical device for locking the manual bolt of its door during the cleaning operation, the oven being characterised in that the electric circuit for energising its heating resistors 3a, 3b comprises a single thermostat 2 adapted to be adjusted for various control conditions including the aforesaid cleaning operation as a function of the angular position of the knob provided for controlling the position of a control switch such switch being so arranged that in the angular position of said knob which precedes the cleaning control position the electromechanical device can be actuated to permit the operation of the door bolt to the door fastening position preliminary to the cleaning operation whereas in the angular position corresponding to the cleaning operation the rotary switch is adapted to energise the heating resistors through contacts 11 which are closed by the movement of the door bolt to the door fastening position and contacts 4 adapted to be opened by a timing or programming device after a time period sufficient for completing the cleaning operation, the circuit for actuating the electromechanical device being completed via the thermostat contacts so that the door can only be opened when the contacts of the thermostat are closed so that opening of the door doing the cleaning operation is prevented. In the construction shown the electromechanical device is of the kind described in Specification 1249454 and which includes an electromagnet 8 which when energised moves a slidable detent to a position in which the door bolt can be moved between fastening and releasing positions and vice versa and which when the electromagnet is de-energised prevents movement of the door bolt. The electromagnet is controlled by a push button switch 9 which when depressed completes its circuit via the thermostat contacts; when the electromagnet is energised a signalling lamp is also energised thus at the end of the cleaning operation if the lamp lights when the push button is depressed the thermostat has closed because the oven temperature has fallen low enough and indicates that the door can be opened. The angular position of the knob which precedes the cleaning operation is also used to. permit the operation of the oven as a grill a resistor 5 being energised in this position instead of the resistor 3a and 3b. When either the resistors 3a and 3b or the resistor 5 is in operation a resistor 6 is also in operation, this is the heating resistor of a catalytic device which is intended to remove fumes. .