GB742730A - Improvements relating to electric cooking equipment - Google Patents

Abstract

742,730. Indicators for switches. SIMPLEX ELECTRIC CO., Ltd. March 4, 1954 [March 11, 1953], No. 6662/53. Class 38(5) [Also in Group XI] An electric cooker having several units,. e.g., an oven, a grill and one or more hotplates each controlled by a switch having: a knob, one or more of the knobs formed of translucent material 26 over the major part of its area, or has a substantial translucent surround and the knobs have individual lamps behind them, each lamp 28 having its terminals or contacts 30 in the rear of an opaque panel or member 13 at the front of which the knob is situated to avoid the passage of leads through the panel to the lamp; and the panel has an aperture 21 or group of apertures masked wholly by the knob alone or in combination with the translucent surround, the current supply to each lamp being effected in dependence on movement of its knob from the off position, so that the lamp indicates when its knob is "on." Each aperture 21 occupies a half or more of the area behind the knob and permits removal of a lamp from the front upon removal of a knob. The translucent part 26 of the knob may be a hollow concave dome with an outer convex face carrying an opaque transverse web 27 serving as a finger piece to operate the knob. An additional lamp for each knob is lit only when a thermostat establishes current supply to a heating unit, is of a different colour- and may be mounted on the holder 30 to illuminate a different paxt of the translucent member. The lamps are supplied from the secondary winding of a common step-down transformer having a primary connected to the main cooker supply. The lamps may be connected across shunt resistors in series with a main heating element or with a ballast resistor. The lamps may be of the gas discharge type energized at mains voltage in parallel with the main heater. The lamps (other than that controlled by a thermostat) may be collectively controlled by a separate switch member as an alternative to the control of the current by switch contacts operated by movement of the knob. The margin of the translucent skirt may have indicia such as "high," "low."