Abstract: An apparatus for detecting the presence and/or the size of a cooking vessel (6) on an electrically heatable hotplate, having a resistance heating element (1) which is disposed under the hotplate and which is connected to an electrical heating voltage supply, wherein the resistance heating element (1) is used as a capacitive sensor for pot detection. The capacitance of the resistance heating element (1) in relation to a reference potential, preferably earth, is connected into an electrical resonant circuit whose resonance frequency can be detected by an evaluation unit, whereby it is possible to ascertain the presence and/or the size of a cooking vessel (6) on the hotplate. The resistance heating element (1) is connected to the heating voltage supply by way of electrical switching means, preferably inductors (DR1, DR2), and is connected into the resonant circuit by way of a further electrical switching means, preferably a separating capacitor (CN).

Abstract: Adjustable electronic temperature control, having a bridge circuit with arms and at least one diagonal connected between points of the bridge, a thermistor for sensing temperature connected in one of the arms, a control circuit to be activated by the temperature control, a circuit for activating an indicating and safety device, at least two amplifiers for switching the control circuit and indicating and safety circuit on and off, means connected in the at least one diagonal for supplying a control voltage to the amplifiers, a plurality of resistors connectible in parallel in another arm for setting a setpoint temperature in the temperature control, the resistors having values increasing in a binary code, and at least one coding switch for selectively connecting the resistors in parallel in accordance with given temperature steps.

Abstract: In an assembly of a work-performing machine having variable torque demand driven by an asynchronous motor, a phase-angle control device for varying the operating voltage of the asynchronous motor in accordance with the respectively required torque, the asynchronous motor being operable with substantially optimal efficiency, by means of said phase angle control device, with the operating voltage matched to the respectively required torque.

Abstract: Refrigeration equipment, particularly a household refrigerator or the like, having a heat-insulated refrigeration chamber and a refrigeration unit which can be switched-on intermittently by a temperature-dependent control and the heat exchanger of which, arranged in the refrigeration chamber, can be defrosted between the cooling periods through the supply of thermal energy and/or natural incidence of heat from the environment of the refrigeration equipment, the control being equipped with two sensors, one of which measures the air temperature in the refrigeration chamber and the other, the temperature at the heat exchanger. The sensors have their switching functions coupled by a mutually interlocking electronic circuit in which the switching function activated by the temperature at one sensor must run down completely before the switching function activated at the other sensor is set in motion.