EP3249302A1 - Domestic cooking device - Google Patents

Abstract

The household cooking appliance (B3) has a plurality of electrically operable radiators (2-5) for heating a cooking chamber, a mechanically switching operation selector switch (8) for connecting at least one radiator (2-5) depending on a set mode, a mechanical temperature controller ( 9) for controlling the activated heating elements (2-5) in dependence on a temperature of the cooking chamber, which mechanical temperature controller (9) with the radiators (2-5) is electrically connected in series, and an electronic circuit (23), wherein a heating circuit relay (10) is electrically connected in series with the radiators (2-5) and the mechanical temperature regulator (9) and can be switched by the electronic circuit (23), the electronic circuit (23) being connected to the operating selector switch (8) is to detect a set by the operation selector switch (8) mode and the electronic circuit (23) is adapted to the Heizkrei s relay (10) in response to the detected operating mode to switch clocking. A method is for operating a household cooking appliance (B3), wherein if an operating mode is selected in which at least one radiator (2-5) is operated clocked, the mechanical temperature controller (9) is set to a higher temperature as an expected maximum oven temperature, in particular to a maximum adjustable temperature. The invention is particularly advantageously applicable to ovens, especially ovens.

Description

The invention relates to a household cooking appliance, comprising a plurality of electrically operable radiators for heating a cooking chamber, a mechanically switching operation selector switch for connecting at least one radiator depending on its switching position, a mechanical temperature controller for controlling the switched radiator depending on a temperature of the cooking chamber, which temperature regulator is electrically connected in series with the radiators, and an electronic circuit. The invention is particularly advantageously applicable to ovens, especially ovens.

DE 10 2011 017 638 A1 relates to a method for operating a cooking appliance, wherein the operation of at least one heating unit of the cooking appliance is at least temporarily carried out by a control unit of the cooking appliance, wherein during a running cooking program in a first time interval, the control unit is activated and the operation of the heating unit is performed by the control unit, and in a second time interval, the controller unit is deactivated and a clocked operation of the heating unit is controlled by a timer of the cooking appliance.

EP 2 063 180 A2 discloses a heating cycle for a cooking chamber of a cooking appliance, comprising the following steps: activation of at least one heating element for heating the cooking chamber until reaching a predetermined limit temperature; following downshifting a heating power of the at least one radiator to allow the cooking chamber to cool below the predetermined threshold temperature; and subsequently clocked activating at least one heater having a predetermined timing characteristic for a predetermined timing time interval for heating the cooking space until reaching the predetermined limit temperature.

EP 1 461 568 B1 discloses a method of controlling energy intake in an oven that is being filled with a food when it is cold and then being heated to its operating temperature at full power during a warm-up period and during a subsequent period of time at which the operating temperature is heated by supplying the full power at a certain repetition rate. An electrical circuit used to carry out the method comprises a thermostat connected in series with the heating elements, timer switching means adapted to provide the desired duty cycle and the desired repetition rate, and the action of the thermostat during operation subsequent heating period override. The timer switch means may be an energy control device connected between the thermostatic switch and the electrical elements in parallel with a first temperature switch which is normally open and closes at a temperature of about 130 ° C and in parallel with a second temperature switch, normally is closed and opens at a temperature of about 65 ° C.

It is the object of the present invention to overcome the disadvantages of the prior art, at least in part, and in particular to provide a household cooking appliance that allows a high number of operating modes at low cost, in particular also at least one special mode.

This object is achieved according to the features of the independent claims. Preferred embodiments are in particular the dependent claims.

The object is achieved by a household cooking appliance, comprising a plurality of electrically operable radiator for heating a cooking chamber, a mechanically switching operation selector switch for connecting at least one radiator in response to a user selected or set switching position, a mechanical temperature controller for controlling the activated radiator in dependence a temperature of the cooking chamber, which mechanical temperature controller is electrically connected in series with the radiators, and an electronic circuit, wherein a first relay (hereinafter referred to as "heating circuit relay" without limitation to the general public) electrically connected in series with the radiators and the mechanical temperature controller is and is switchable by means of the electronic circuit, the electronic circuit is connected to the operation selector switch to detect a set by the operating selector switch position and the electr Onic circuit is adapted to switch the heating circuit relay in response to the detected switching position of the operation selector switch.

This household cooking appliance has the advantage that it can work like a purely mechanically controlled cooking appliance, wherein or as long as the heating circuit relay is permanently closed during operation, which allows a particularly inexpensive structure. In addition, the household cooking appliance is able to operate the radiator by means of a particularly simple and inexpensive electronic unit via a corresponding control of the heating circuit relay during operation switching. The electronic unit can be kept simple, since basic functionalities such as a temperature setting, a temperature measurement and a control are already covered by the very cost-effective mechanical temperature controller. Such a household cooking appliance is only slightly more expensive than a purely mechanically controlled cooking appliance, which has an electronic clock for a clock display or for the provision of a timed operation (ie, a time-limited or delayed operation), but considerably cheaper than a purely electronically controlled cooking appliance ,

The functionality of switching the heating circuit relay during operation can also be described as a special functionality. An operating mode in which the heating circuit relay is switched during operation can also be referred to as a special operating mode. A special function can be, for example, the function "temperature reduction". In this case, a cooking chamber temperature is adjusted by means of the mechanical Tempertaturreglers to a predetermined setpoint. If, for example, the setpoint is above a predetermined threshold value, the radiators are switched, in particular clocking, after a period of time which may be dependent on temperature, in order to lower the cooking chamber temperature, for example by 30 ° C. As a result, for example, a temperature of a viewing window of a cooking chamber door can be kept below a desired value, which increases user safety. A cooking result is not or only slightly changed by the temperature reduction. Possibly. May a cooking time be extended. An operating mode which has the special function "temperature reduction" can itself be a special operating mode ("safety cooking"). This special mode can be considered as a "hybrid" mode of operation if it has conventional operating sections which control the temperature by means of the temperature controller and operating sections which switch, in particular clocking, by means of the radiator relay.

Another possible special mode may be the energy-saving mode (so-called "energy saving mode"), in which a predetermined amount of heat per unit time is introduced into the cooking chamber. This can be done by a timed operation of the radiator used with a predetermined duty cycle. A regulation of the cooking space temperature does not take place here. Another special mode may be a low-temperature cooking or a single-burner automatic.

The Heizkreisrelais can also be switched to the realization of a time-limited operation or a time-shifted operation, but this is not regarded as a special functionality. In particular, such a switching of the radiator may not be considered as running.

The fact that the electronic circuit is adapted to switch the heating circuit relay in dependence on the detected switching position and thus operating mode, may include that the heating circuit relay can be switched on and off during operation. This may include switching with a predetermined shift pattern or shift rule. In particular, the switching on and off may comprise a clocking switching, e.g. with a given duty cycle, a given pulse duration, etc.

The household cooking appliance has at least one cooking chamber. The household cooking appliance has at least one oven functionality, possibly also a steam feed functionality, in particular a steam cooking functionality. The household cooking appliance may be a stand-alone cooking appliance or a cooking appliance / hob combination or stove.

The radiators may, for example, have at least one top heat or grill radiator, a bottom heat radiator and / or a ring or Umluftheizkörper. These radiators can be resistance heaters.

The mechanically switching operation selector switch is adapted to open or close by means of a manual operation at least one associated electrical contact in dependence on the selected or actuated switching position and thus operating mode. In particular, by opening or closing the at least one contact at least one radiator can be switched on for operation under the set operating mode. The operation selector switch can be used for different switch positions or operating modes switch on different radiators or combinations of radiators. The operation selector switch can also be called a preselection switch.

The mechanical temperature controller is set up to regulate the cooking chamber temperature as a function of a setpoint temperature set by a user. This is done without electronic control contributions, but mechanically or electromechanically, e.g. by means of a capillary tube regulator. A mechanical temperature controller is very inexpensive and robust.

The mechanical temperature controller can also be referred to as an electromechanical temperature controller, mechanical thermoregulator or thermostat. The mechanical temperature controller may be, for example, a capillary tube regulator, a bimetallic switch, etc.

The mechanical temperature controller is electrically connected in series with the radiators, so that a flow of current through the radiator is made possible by the mechanical temperature controller. If the temperature applied to the mechanical temperature controller is above the set target temperature, an electrical contact of the mechanical temperature controller is open, and no current flows through the radiator. If the temperature applied to the mechanical temperature controller is below the set target temperature, the electrical contact of the temperature controller is closed and current can flow through the (connected) radiators.

The electronic circuit may be a simple electronic circuit with an integrated circuit - eg a controller - that can control or switch the heating circuit relay. The heating circuit relay may be a component of the electronic circuit. The electronic circuit, the Heizkreisrelais clocking, ie, in particular, with a predetermined duty cycle and a predetermined period, switch. The electronic circuit can also keep the heating circuit relay closed for at least one specific operating mode. In general, the electronic circuit can switch and in particular have at least one relay for switching at least one load (in particular radiator and / or secondary consumer), which enables a particularly compact circuit.

The heating circuit relay can be an electrically controlled, mechanically switching relay. The heating circuit relay may alternatively be an electronically controlled switching element such as a triac or similar. be. Under a Heizkreisrelais can thus be understood generally electrically or electronically controlled switching element.

The heating circuit relay is electrically connected in series with the (connected) radiators and the electrical contact of the mechanical temperature controller, which allows a particularly simple circuit.

It is an embodiment that the electronic circuit is adapted to clock the heating circuit relay for at least one special mode (e.g., for a power saving mode) while in operation and to close or permanently close at least one other conventional mode of operation. It is exploited that with mechanical temperature regulators at low temperatures no satisfactory cooking result is obtained, since the mechanical temperature controller then have too high inertia. Thus, the mechanical temperature controller for high temperatures as previously used in mechanically controlled ovens for temperature control, especially in conventional modes such as a grill mode, a recirculation or hot air mode, a top and / or bottom heat mode, etc. At low temperatures However, a clocked low-temperature operation of the radiator results in better cooking results. The clocked operation may only be controlled. The mechanical temperature controller is then preferably set to remain closed during the operation of the low-temperature mode. It can then be used as an additional overheat protection. A low temperature mode may e.g. gentle cooking (also known as low-temperature cooking) or energy-saving mode.

It is still an embodiment that electronic circuit is an electronic clock circuit ("electronic clock") for time-limited and / or delayed operation of the at least one radiator. Such a clock circuit is available at low cost and comes in particular with a few electronic components, eg with a microcontroller. In particular, the clock circuit can have a microcontroller, the heating circuit relay for controlling a current flow at least through the radiators and processing an input signal coming from the operation selection switch. The electronic watch circuit can thus also be used in this embodiment to control consumers (in particular radiator) in a running operation or to regulate.

It is an embodiment of the fact that the heating circuit relay for time-controlled time-limited or time-shifted operation is switched on and off. In other words, the relay used in conventional timepieces for timed (i.e., timed or staggered) operation of the radiators can now be used in addition to turning on and off the radiators during operation. This provides the advantage that conventional clock circuits need only be modified slightly, possibly even by adjusting their software or firmware.

It is a further embodiment that the operation selector switch is a rotary selector switch having a Kodierschalterplatine whose output is connected to an input of the electronic circuit. Alternatively, the rotary selector switch instead of a Kodierschalterplatine have simple switched contacts. These embodiments provide the advantage that information about a selected operating position or mode of operation to the electronic circuit is easy and inexpensive übermittebar.

It is still a further embodiment that the electronic circuit has a main relay, which is connected in series with the radiators and auxiliary consumers of the household cooking appliance. As a result, particularly many, in particular all, consumers can be switched off together by means of only one relay.

Additional consumers may include, for example, an oven light (e.g., an oven light), a circulating air motor, an oven indicator light, and / or a cooling fan motor.

It is also an embodiment that the electronic circuit can switch another relay ("Nebenverbraucherrelais"), which is connected in series with at least one auxiliary consumer of the household cooking appliance and independently, for example, parallel to the radiators. A radiator power is not switched in particular via the secondary consumer relay. Thereby, the auxiliary load relay can be carried out inexpensively, since only small currents are switched. Furthermore, the at least one Nebenverbraucher be switched so independent of the radiators. This allows a more flexible possibility of an independent - eg temporally staggered - operation of radiators and auxiliary consumers. In particular, the radiator can be switched off by means of a common relay (namely the heating circuit relay), which allows a particularly high level of security, while the at least one secondary consumer is still operable. The electronic circuit may have the secondary consumer relay or the secondary consumer relay may be a component of the electronic watch circuit, which allows a particularly compact circuit.

It is also an embodiment that at least one cooling fan motor in series with the secondary consumer relay, and in particular independently, e.g. parallel, arranged to the other consumers. As a result, the cooling fan motor can be switched independently (for example, switched on or off) by means of the electronic circuit, at least to the radiators (and possibly also to other secondary consumers), in particular temperature-controlled or time-controlled. The otherwise usual for mechanically controlled cooking appliances control of a Lüftternachlaufs over a temperature limiter (for example, a Klixon) can be omitted. Furthermore, it is easier compared to today known circuits of mechanically controlled devices to test the control and function of a driven by the cooling fan motor cooling fan in the final test. In the usual control of the cooling fan via a temperature limiter, the verification of the functional effect of the switching of the temperature limiter is possible only with additional effort, such. by elaborate heating of the temperature limiter or by an additional bridging of the temperature limiter. By integrating the function in the clock circuit or electronic circuit, this can advantageously be done by turning on the secondary consumer relay using a test program.

It is a further development that the oven lighting, the circulating air motor and the oven operation indicator lamp (possibly all located auxiliary consumers except for the cooling fan motor, if present) are each connected in series with the operating selector switch, in particular so that in an off position of the selector switch the Circuits of these consumers are interrupted. It can thereby be achieved that only the cooling fan motor can also be operated in an off position of the operating selector switch.

In particular, at least one cooling fan motor can be switched independently of the other consumers depending on the position of the rotary selector and be arranged in this position of the rotary selector in series with the main relay. Also, at least one cooling fan motor depending on the position of the rotary selector can be switched independently of the other consumers and be arranged in this position of the rotary selector in series with the secondary consumer relay.

It is also an embodiment that the electronic circuit is connected to a temperature sensor or temperature sensor for measuring a cooking chamber temperature. Through the integration of the simple "electronic temperature measurement" the possibility is created in a cost-effective manner that control and / or regulating functions effected by the electronic circuit can take place as a function of the cooking chamber temperature. For example, an adaptation of the electronic parameters (for example the clock ratio) to the currently present cooking chamber temperature can now also be achieved with a switching, in particular clocked, operation of the radiator via the electronic circuit. Thus, the electronic circuit can regulate the cooking chamber temperature by switching the heating circuit relay or control temperature-dependent. The still existing mechanical temperature controller can be used in particular to ensure operational safety, in particular against overheating. For example, it can also be avoided that the electronic circuit must meet increased safety requirements, which would make it considerably more expensive.

It is a further development that a parameterization of control values for clocked modes is used, which allows a higher energy saving (for example in the energy-saving mode). In addition, this improves reliability to achieve a good cooking result, since a better adapted energy input is possible.

It is a special development that a temperature-dependent parameterization of control values for clocked operating modes is used, which enables even greater energy savings. As a result of the electronic temperature measurement, better adapted control / regulation parameters for a switched, in particular clocked, operation of the radiators during operation can be provided. The parameters for the pulsed operation can thus be dependent on the oven temperature be varied in order to achieve a higher energy saving with improved cooking quality.

In a further development, a wake of a cooling fan (for example, its duration or "follow-up duration") and / or its speed as a function of the cooking chamber temperature can be controlled, for example by a temperature-dependent switching of the secondary consumer relay. This results in the advantage that the follow-up time is not unnecessarily long, but sufficient cooling and a Entwrasung the cooking chamber can be achieved. The energy consumption and the noise pollution during the fan overrun are thereby reduced.

It is also a development that a temperature-based door opening recognition is integrated in the electronic circuit, for example to ensure a subsequent operation (i.e., an operation after a preset cooking time has elapsed) without disadvantages for the cooking result. This can be implemented by means of the electronic temperature measurement and a correspondingly implemented algorithm for the evaluation of the temperature profile of the cooking appliance. For example, the oven temperature can be controlled and / or regulated differently after detecting a collapse of the oven temperature in order to compensate for the influence of this temperature drop. In particular, the clocked operation can be interrupted for the required compensation duration. The temperature drop can e.g. have been effected by opening a cooking chamber door.

It is still a further development that the cooking chamber temperature can be reduced on the device side as a function of the electronically measured cooking chamber temperature, in particular can be controlled or regulated in terms of time and / or temperature. This may include, for example, that a cooking chamber temperature set by the thermostat (e.g., of 270 ° C) is automatically lowered (e.g., to 230 ° C) after a predetermined period of time by the electronic circuit to limit a front temperature to the cooking chamber door. This lowering of the oven temperature can e.g. be achieved by a correspondingly long and / or frequent opening of the heating circuit relay.

Preferably, the temperature sensor on the holder of the sensor of the temperature controller (preferably capillary tube controller), with which this is attached to or in the oven, attached, since there are different temperatures relative to a cooking chamber center temperature at different operating modes.

The object is also achieved by a method for operating the household cooking appliance as described above, wherein when an operating mode is selected in which at least one radiator is operated clocked, the mechanical temperature controller is set to a temperature which is higher than one expected maximum oven temperature, in particular to a maximum adjustable temperature. Thus, it can be prevented particularly reliably and with simple means that the mechanical temperature controller intervenes in a switching, in particular clocked, operation of at least one consumer in its operation, as expected, the mechanical temperature controller then remains closed.

The object is also achieved by methods corresponding to the above-mentioned special functions and / or special modes, e.g. Temperature reduction, energy saving mode, etc.

Fig.1

zeigt eine erste Schaltung eines ersten Backofens;

Fig.2

zeigt eine zweite Schaltung eines zweiten Backofens; und

Fig.3

zeigt eine dritte Schaltung eines dritten Backofens.

The above-described characteristics, features and advantages of this invention, as well as the manner in which they are achieved, will become clearer and more clearly understood in connection with the following schematic description of an embodiment which will be described in detail in conjunction with the drawings.

Fig.1

shows a first circuit of a first oven;

Fig.2

shows a second circuit of a second oven; and

Figure 3

shows a third circuit of a third oven.

Fig.1 shows a first circuit 1 for operating a household appliance in the form of a first oven B1 under several modes. For this purpose, the oven B1 several radiators, namely here, for example, a first Oberhitze- or Grillheizkörper 2, a second Oberhitze- or Grillheizkörper 3, a Unterhitzeheizkörper 4 and a circulating air or ring heater 5. The radiator 2 to 5 are electrically connected to an outer conductor L. (eg operated with an alternating voltage of 230 V) and connected to a neutral conductor N. The radiators 2 to 5 are arranged here for example electrically parallel to each other.

Between the radiator 2 to 5 on the one hand and the neutral conductor N on the other hand, a temperature limiter 6 is connected. Further, between the outer conductor L and the radiators 2 to 5 in series: a main relay 7, a mechanical rotary selector 8, a mechanical temperature controller - here e.g. designed as a user-adjustable capillary tube 9 - and a heating circuit relay 10 connected. The main relay 7 and the heating circuit relay 10 are components of a watch circuit 11.

The watch circuit 11 is constructed as an electronic circuit and may include at least one integrated circuit (e.g., a microcontroller, not shown), etc., other than the relays 7 and 10. *** " The clock circuit 11 is used, inter alia, to control the time of the oven B1 (e.g., to implement a timer function and to display the time), and may include a display 12 (e.g., a 7-segment display). The clock circuit 11 is connected here directly between the outer conductor L and the neutral conductor N. The clock circuit 11 is also set up so that it can switch the heating circuit relay 10 and / or the main relay 7.

Further, an input 13 of the watch circuit 11 is connected to an output 14 of the rotary selector switch 8. Rotary switch 8 is provided with an encoder 15 (e.g., in the form of a coded circuit board, e.g., based on bit coding using, for example, a gray code), which assigns an output signal or unique electrical interface configuration to each rotary position of rotary switch 8. Therefore, the watch circuit 11 can recognize (for example by means of a suitable evaluation logic or evaluation circuit) in which rotational position the rotary selector switch 8 is located. A rotational position of the rotary selector switch 8 may correspond in particular to a respective operating mode.

The rotary selector 8 is also designed and arranged so that it connects between the main relay 7 and the capillary tube 9, between the temperature limiter 6 and the neutral conductor N, between the radiators 2 to 5 and the heating circuit controller 10, between the radiators 2 to 5 and the watch circuit 11, between the radiators 2 to 5 and a circulating air motor 16 and between the circulating air motor 16 and the neutral conductor N can optionally close and open. All of these connections can be individually closed or opened depending on the selected rotational position be. In an off or zero position, in which no mode is selected, the rotary switch 8 may be arranged so that all connections are open. In particular, each of these compounds can be assigned a mechanical single switch Sn (n = 1,..., 9) of the rotary selector switch 8, which then correspondingly has a plurality of such individual mechanical switches Sn. The individual switches Sn can be actuated, for example, by means of a suitable shaft, for example connected to a rotary knob. In principle, each dialing position of the rotary selector switch 8 can be associated with any but fixed combination of the closed states (open / closed) of the individual switches Sn.

The individual switches S1 to S8 may comprise for example: a single switch S1 between the capillary tube regulator 9 and the heating relay 7, a single switch S2 between the first grill heater 2 and the heating circuit relay 10, a single switch S3 between the second grill heater 3 and the heating circuit relay 10, a single switch S4 between the lower heat radiator 4 and the heating circuit relay 10, a single switch S5 between the circulating air heater 5 and the heating circuit 10, a single switch S6 between the neutral conductor N and the temperature limiter 6, a single switch S7 between the individual switches S2 to S5 and a signal input of the clock circuit 11, a Single switch S8 between the single switch S6 and the circulating air motor 16 and a single switch S9 between the individual switches S2 to S5 and the circulating air motor 16. The clock 11, the off position of the rotary switch 8 by a corresponding bit code - eg "000" - recognize.

In addition to the circulating air motor 16, additional auxiliary consumers are connected between the outer conductor L and the neutral conductor N. For example, an oven lamp 17 is present, which is connected on the one hand between the individual switch S1 of the rotary selector switch 8 and the capillary tube 9 and on the other hand between the temperature limiter 6 and the individual switch S6. An oven operation indicating lamp 18 is connected in parallel to the oven lamp 17. A cooling fan motor 19 is connected on the one hand directly to the neutral conductor N and on the other hand connected between the individual switch S1 of the rotary selector switch 8 and the main relay 7. All consumers described 2 to 5 and 16 to 19 except for the clock circuit 11 are thus electrically connected in series with the main relay 7, so that when the main relay 7 is open, these consumers 2 to 5 and 16 to 19 are not supplied with electrical voltage and consequently switched off are.

To operate the oven 1, a user turns the rotary selector switch 8 from its off or zero position to an operating position that corresponds to an operating mode desired by the user. The mode of operation may be a common mode for ovens with mechanical oven controls (e.g., capillary tube regulators 9) such as a grill mode, a bottom heat and / or top heat mode, or a recirculation mode. However, the heating circuit relay 10 which can be controlled by the clock circuit 11 also allows switching operation with special operating modes such as gentle cooking (low-temperature cooking), energy-saving cooking etc. For the usual operating modes, the heating circuit relay 10 is not required for controlling a cooking chamber temperature and is in the ongoing operation permanently closed.

Set a user on the rotary selector 8, for example, the grill mode, so the rotary selector switch 8 closes the single switch S1 between the capillary tube 9 and the heating relay 7, the single switch S6 between the neutral conductor N and the temperature limiter 6 and the individual switches S2 and S3 between the grill 2 3 and the heating circuit relay 10. In addition, the individual switch S7 between the grills 2 and 3 and the clock circuit 11 will be closed, so that the clock circuit 11 receives a feedback that at least one of the radiator 2 to 5, a voltage is applied and therefore - if the temperature limiter 6 is closed - heats the radiator.

By contrast, the individual switches S4 and S5 are open so that the radiators 4 and 5 are not operated. In addition, the individual switches S8 and S9 are open, so that the circulating air motor 16 is not operated.

Furthermore, a corresponding bit code can now be read from the watch circuit 11 at the rotary selector switch 8 or a corresponding bit code is now output to the watch circuit 11 from the rotary selector switch 8. The clock circuit 11 processes the bit code (eg by means of a corresponding processing device) and switches the heating circuit relay 10 accordingly or leaves it in the starting position. As a result, an electrical connection between the Grillheizkörper 2 and the capillary tube 9 is made so that the grill element 2 is now connected to both the outer conductor L and to the neutral conductor N and therefore with electrical energy is available. The associated temperature control takes place as usual via a temperature setting on the capillary tube regulator 9.

Furthermore, a time-shifted and / or a time-limited operation of the grill mode can be set via the clock circuit 11, e.g. starting in one hour after activation with a duration of two hours. The clock circuit 11 opens or closes the main relay 7 and the Heizkreisrelais 10 accordingly.

If a recirculation mode is selected on the rotary selector switch 8, instead of the switches S2 and S3, the switch S5 can be closed in order to operate only the circulating air heater 5. In this case, the switch S8 may be closed to operate the circulating air motor 16.

For special modes, the functionality of the capillary tube regulator 9 is not sufficient, since it is not possible, depending on the selected mode, e.g. to control an energy input into the oven via parameters of the watch 11. When a special mode is selected on the rotary switch 8, e.g. an energy-saving mode, the matching at least one radiator from the group of radiators 2 to 5 is connected by closing the corresponding individual switch S2 to S5, possibly also the circulating air motor 16, similar to the selection of a previously customary operating mode.

In contrast to one of the usual operating modes, however, the heating circuit relay 10 is now switched on and off by the clock circuit 11, in particular clocked, so that the appropriate radiators 2 to 5 are switched on and off, in particular clocked. In particular, no regulation of the temperature in an associated cooking space or oven space of the oven 1 takes place, or is the clocking (eg a period, a duty cycle, etc.) not dependent on an oven temperature in the oven space. For this purpose, the capillary tube regulator 9 may have been adjusted by a user to a temperature value (at which the capillary tube regulator 9 opens or interrupts) which is above a temperature value typically achievable in the selected special mode, for example to a maximum adjustable temperature value. The suitable for the selected special mode timing parameter (period, duty cycle, etc.) can determine or set the clock circuit 11 based on the transmitted or read from the rotary selector 8 bit code.

Consequently, the oven 1 modes (especially for standard operating modes) by means of a mechanical thermal control via the mechanically adjustable rotary selector 8 and the capillary tube 9 perform and perform in at least one mode in a simple and very inexpensive way a switching, in particular clocked, controlled heating operation.

Thus, it can cost-effectively function, e.g. an energy saving mode and / or a temperature reduction, are offered in cooking appliances with a mechanical control. The electronic unit embodied here as a clock circuit 11 can be kept particularly simple since basic functionalities (temperature setting, temperature measurement and control) are already covered by the very cost-effective mechanical control element (for example the capillary tube regulator 9), in particular for conventional operating modes.

Fig.2 shows a second circuit 21 of a second oven B2. The circuit 21 differs from the circuit 1 in that the main relay 7 is missing, but another relay ("secondary load relay" 22) is present on the watch circuit 23. The secondary consumer relay 22 is electrically connected in series with the auxiliary consumers 16, 17 and 19, so that they are advantageously operable even when the radiator 2 to 5 are switched off by continuous opening of the heating circuit 10. In addition, now the cooling fan motor 19 can be operated independently of the radiators 2 to 5 through the oven B2, for example, to allow a Nachlauflassens a cooling fan motor 19 and thus possibly associated Entwrasung in a simple manner. The heating circuit relay 10 has the same function in the circuit 21 as in the circuit 1.

Figure 3 shows a third circuit 31 of a third oven B3, which differs from the second circuit 21 in that the clock circuit 23, a temperature sensor or temperature sensor 32 is connected to measure a furnace temperature, for example, an NTC resistor or a PTC resistor, eg a platinum measuring resistor, eg of the type Pt 500. The clock circuit 23 may have a matching measuring circuit for this purpose. The temperature sensor 32 allows temperature control for special programs in which the capillary tube 9 is set so that it has no control function takes over. However, the capillary tube regulator 9 - as well as in Fig.1 and Fig.2 - Take over a security function, so that the clock circuit 23 is still particularly easy and inexpensive to implement.

By integrating such a simple "electronic temperature measurement", the possibility is created in a cost-effective manner that control and / or regulating functions effected by the electronic circuit 23 can take place as a function of the cooking chamber temperature. In particular, a temperature-dependent parameterization of control values for clocked operating modes can be used. Furthermore, by means of the clock circuit 11, a follow-up run of a cooling fan or the associated cooling fan motor 19 can be controlled as a function of the cooking chamber temperature. Also, the clock circuit 11 may be configured to implement a temperature-based door opening recognition. In addition, the clock circuit 11 may be adapted to reduce the cooking chamber temperature depending on the electronically measured cooking chamber temperature on the device side.

Preferably, the temperature sensor 32 is attached to the holder (not shown) of the sensor of the capillary tube regulator 9.

Of course, the present invention is not limited to the embodiments shown.

Generally, "on", "an", etc. may be taken to mean a singular or a plurality, in particular in the sense of "at least one" or "one or more" etc., unless this is explicitly excluded, e.g. by the expression "exactly one", etc.

Also, a number may include exactly the specified number as well as a usual tolerance range, as long as this is not explicitly excluded.

LIST OF REFERENCE NUMBERS

1

circuit

2

First grill radiator

3

Second grill radiator

4

Bottom heating element

5

Recirculating air heating

6

Temperature

7

main relay

8th

rotary dial

9

Capillary tube

10

Heizkreisrelais

11

watch circuit

12

display

13

Clock input

14

Output of the rotary selector switch

15

coding

16

recirculated air motor

17

oven light

18

Oven pilot lamp

19

Cooling fan motor

21

circuit

22

In addition to consumer relay

23

watch circuit

31

circuit

32

temperature sensor

A

outer conductor

B1

oven

B2

oven

B3

oven

N

neutral

S1-S9

Single switch

Claims (14)

Household cooking appliance (B1, B2, B3), comprising - Several electrically operated radiator (2-5) for heating a cooking chamber, a mechanically switching operating selector switch (8) for connecting at least one heating element (2-5) as a function of its switching position, - A mechanical temperature controller (9) for controlling the activated radiator (2-5) in response to a temperature of the cooking chamber, which mechanical temperature controller (9) with the radiators (2-5) is electrically connected in series, and an electronic circuit (11, 23), characterized in that - A heating circuit relay (10) with the radiators (2-5) and the mechanical temperature controller (9) is electrically connected in series and by means of the electronic circuit (11; 23) is switchable, - The electronic circuit (11, 23) is connected to the operation selector switch (8) to detect a set by the operating selector switch (8) switching position and - The electronic circuit (11, 23) is adapted to switch the heating circuit relay (10) in response to the detected switching position during operation. Household cooking appliance (B1; B2; B3) according to claim 1, characterized in that the electronic circuit (11; 23) is adapted to that for at least one special operating mode during operation to switch Heizkreisrelais (10) clocking and for at least one further Closing the operating mode. Household cooking appliance (B1; B2; B3) according to one of the preceding claims, characterized in that electronic circuit (11; 23) is an electronic watch circuit for the time-controlled operation of the at least one heating body (2-5). Household cooking appliance (B1, B2, B3) according to claim 3, characterized in that the heating circuit relay (10) for timed operation is switched on and off. Domestic cooking appliance (B1; B2; B3) according to one of the preceding claims, characterized in that the operating selector switch (8) is a rotary selector switch whose output is connected to an input of the electronic circuit (11; 23). Domestic cooking appliance (B1) according to one of the preceding claims, characterized in that the electronic circuit (11) has a main relay (7) connected in series with the radiators (2-5) and with auxiliary consumers (16-19) of the household -Gargerät (B1) is switched. Household cooking appliance (B2; B3) according to one of the preceding claims, characterized in that the electronic circuit (23) has a secondary consumer relay (22) connected in series with at least one secondary consumer (16-18) of the household cooking appliance (B2; B3) and independent of the radiators (2-5) is switched. Household cooking appliance (B3) according to one of the preceding claims, characterized in that the electronic circuit (23) is connected to a temperature sensor (32) for measuring a cooking chamber temperature and is adapted to regulate the cooking chamber temperature thus measured by switching the heating circuit relay or to control. Domestic cooking appliance (B3) according to claim 8, characterized in that a wake of a cooling fan (19) in dependence on the temperature of the sensor (32) measured cooking chamber temperature is controllable. Household cooking appliance (B3) according to one of the preceding claims, characterized in that the electronic circuit (23) is adapted to use a parameterization, in particular temperature-dependent parameterization of control values for by means of the heating circuit relay (10) clocked modes. Household cooking appliance (B3) according to one of claims 8 to 10, characterized in that the electronic circuit (23) is arranged to perform a door opening detection. Household cooking appliance (B3) according to one of claims 8 to 11, characterized in that the cooking space temperature in dependence on the measured by means of the temperature sensor (32) cooking chamber temperature on the device side can be reduced. Household cooking appliance (31) according to any one of claims 8 to 12, characterized in that the temperature sensor (32) is attached to a holder of a sensor of the mechanical temperature controller (9) with which it is attached to the or in the cooking chamber. Method of operating a household cooking appliance (B1; B2; B3) according to any one of the preceding claims, characterized in that when a mode is selected, is operated clocked at the at least one radiator (2-5), the mechanical temperature controller ( 9) is set to a temperature which is higher than an expected maximum oven temperature, in particular to a maximum adjustable temperature.

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