Abstract: The design and evaluation of sensor elements, such as used in an electric hob, of an operating device is simplified. For this purpose, the sensor elements are configured in such a manner so as to have differently sized sub-area regions. When a finger is placed on a cover above the sensor element according to the mark provided thereon, a contact surface is created above the sensor element. By this contact surface a corresponding operating signal having variable characteristics is triggered, which can then be associated with a corresponding operating function.

Abstract: The invention provides according to one example a display device for a domestic electric heating appliance, such as for example a glass ceramic hob, the electric heating appliance having at least one heating device. The latter is subdivided into several flat heating areas, which can be activated at least partly independently of one another and/or singly for heating operation. The display device optically displays the heating operation or the activation of individual heating areas. For this purpose it has individually activatable illuminating devices. The illuminating devices are constructed as separate segments of a geometrical basic shape, such as a rectangle or preferably a circle. For each display device there are two basic shapes of the same nature, but different size and having a concentric arrangement.

Abstract: The invention provides according to one example a display device for a domestic electric heating appliance, such as for example a glass ceramic hob, the electric heating appliance having at least one heating device. The latter is subdivided into several flat heating areas, which can be activated at least partly independently of one another and/or singly for heating operation. The display device optically displays the heating operation or the activation of individual heating areas. For this purpose it has individually activatable illuminating devices. The illuminating devices are constructed as separate segments of a geometrical basic shape, such as a rectangle or preferably a circle. For each display device there are two basic shapes of the same nature, but different size and having a concentric arrangement.

Abstract: A touch switch layout for a hob having several hotplates is described. For said hotplates is in each case provided a separate selection switch with which the power can be selected in each case. There is also a single, common touch switch for power reduction for all the hotplates. According to the associated operating method, on operating the common power control switch only the power of a selected hotplate is modified or reduced. The power of a hotplate is increased by briefly operating a selection button as selection and renewed operation of the selection button as an increase. This then functions as a power increase switch. It is obvious that the function can also be reversed.

Abstract: A description is given of a temperature detection device for an electric radiant heater, with which is associated an active sensor for detecting the positioning of a cooking vessel on a hotplate, particularly a glass ceramic plate, covering the radiant heater. This sensor is part of an inductive resonant circuit of a control means and preferably has a single sensor loop of electrically conductive material located in the vicinity of at least one heating zone heatable by electric radiant elements and preferably partly overlapping the same. According to the invention, with at least one portion the sensor loop forms a functional element of a temperature sensor of the temperature detection device. For example, a tubular sensor loop portion can serve as a supporting or protective jacket of a jacket thermocouple.

Abstract: The invention in one embodiment provides a circuit arrangement for a sensor element of a contact switch, in which a high frequency control signal (13) is applied to the sensor element (15). The circuit arrangement (11) has a signal source (12) for the control signal (13), a transistor (T), to whose base (B) is applied across a pass filter (R1, C1) and a voltage divider (C1, 15) the control signal (13), a resistor (R2) applied to ground (18) ensuring a certain base current, the transistor collector (C), to which the output signal (17) is applied, is connected to ground across a capacitor (C2), whilst between the transistor base (B) and ground is located a capacitive sensor element (15). A preferred application field of the invention is a touch contact switch of a glass ceramic hotplate of an electric cooker.

Abstract: A circuit layout for several sensor elements of touch switches is described. It is subdivided into a control part with a control signal and a sensor part with several sensor branches, which in each case contain a capacitive sensor element. An evaluating part inter alia has a capacitor, where an analog output signal can be tapped. By means of connecting means, e.g. in the form of transistors or diodes, with a corresponding control in each case precisely one sensor branch is connected to the remaining circuit and the corresponding sensor element is controlled and evaluated.

Abstract: A touch switch layout for a hob having several hotplates is described. For said hotplates is in each case provided a separate selection switch with which the power can be selected in each case. There is also a single, common touch switch for power reduction for all the hotplates. According to the associated operating method, on operating the common power control switch only the power of a selected hotplate is modified or reduced. The power of a hotplate is increased by briefly operating a selection button as selection and renewed operation of the selection button as an increase. This then functions as a power increase switch. It is obvious that the function can also be reversed.

Abstract: A description is given of a temperature detection device for an electric radiant heater, with which is associated an active sensor for detecting the positioning of a cooking vessel on a hotplate, particularly a glass ceramic plate, covering the radiant heater. This sensor is part of an inductive resonant circuit of a control means and preferably has a single sensor loop of electrically conductive material located in the vicinity of at least one heating zone heatable by electric radiant elements and preferably partly overlapping the same. According to the invention, with at least one portion the sensor loop forms a functional element of a temperature sensor of the temperature detection device. For example, a tubular sensor loop portion can serve as a supporting or protective jacket of a jacket thermocouple.

Abstract: The invention in one embodiment provides a circuit arrangement for a sensor element of a contact switch, in which a high frequency control signal (13) is applied to the sensor element (15). The circuit arrangement (11) has a signal source (12) for the control signal (13), a transistor (T), to whose base (B) is applied across a pass filter (R1, C1) and a voltage divider (C1, 15) the control signal (13), a resistor (R2) applied to ground (18) ensuring a certain base current, the transistor collector (C), to which the output signal (17) is applied, is connected to ground across a capacitor (C2), whilst between the transistor base (B) and ground is located a capacitive sensor element (15). A preferred application field of the invention is a touch contact switch of a glass ceramic hotplate of an electric cooker.