EP2463584B1 - Cooking device - Google Patents

Description

The invention relates to a cooking appliance, in which a cooking space divider can be used.

Cooking chamber divider or baking chamber divider are known from the prior art. So shows DE 102 58 727 A1 an oven with a cooking chamber, on whose lateral boundary walls guide means are formed for receiving a cooking chamber divider. At the top of these guide webs electrical contacts are provided, which are contacted with at the bottom of the cooking compartment divider downwardly extending electrical contacts.

Out DE 100 65 251 A1 a cooking appliance is known in which a cooking space divider can be used. The cooking compartment divider has on its rear side rearwardly extending electrical contacts, which are contacted with electrical contacts of the rear wall of the garraumbegrenzenden muffle.

[ EP 0 967 441 A2 ] relates to an oven with a closable by a door oven muffle in which on a support member a food support is halterbar, which has its own Gargutträgerheizelement. About a Stromzuführelement the Gargutträgerheizelement with the electrical voltage of the oven can be fed. The support member for the food support also serves as the power supply element. About two arranged in a circuit door switch, the power supply of Gargutträgerheizelementes can be switched off with the door open.

[ DE 10 2009 002 864 A1 ] relates to a household appliance device with a household appliance (eg oven), which has a detection unit for detecting a household accessory (eg baking sheet). The detection unit is provided to capture in the household accessories in each case two parameters, namely a parameter on the basic form of the main body of household accessories and a parameter on a material of household accessories. Furthermore, the detection unit is provided to detect positions of household accessories within the cooking chamber.

[ WO 2011/076580 A1 ] concerns a cooking appliance which at least one arranged in a cooking space busbar for the electrical supply of a in the cooking chamber having operable electrical load, wherein at least one busbar by means of a safety device is switched off stress. The safety device may include a door opening monitoring, in particular a door contact switch.

US 3,146,338 discloses an electric oven comprising (a) a charging port for the furnace, (b) a closure member for the charging port, (c) a support member mounted within the furnace for movement in and out of the furnace, (d) an electrical resistance heating element, supported by the support member, (e) electrical connection means disposed within the furnace, (f) the heating element having terminals adapted to releasably engage the connection means when the support member enters the furnace (g) a normally open electrical switching means adapted to be closed by the closure element only when the closure element is moved to the closed position, and immediately after it has completed movement of the closure element to the open position to open after movement of the closure element from the closed position and (h) means for electrically interconnecting the switching means in series with the connection means to control application of electrical energy to the connection means such that the series connection is opened by movement of the closure member from the closed position to prevent movement of the support member out of the closed position Allow interior of the furnace in a position to separate the terminals and the connecting means.

In this case, it is disadvantageous that, for safety reasons, conventional cooking space dividers require two lines for the power supply and a separate line for the protective ground. For this purpose, contact solutions, e.g. 3-pin plugs required, which are big, chunky and elaborate in the realization.

The object of the invention is to avoid the above-mentioned disadvantages and in particular to provide a solution which combines a high degree of security with a practical and cost-effective realization.

This object is achieved according to the features of the independent claim. Further developments of the invention will become apparent from the dependent claims.

To achieve the object, a cooking appliance is specified with a door safety circuit, which is at least partially connected in series with an electrical connection for contacting a cooking chamber divider.

The cooking appliance may in particular be an oven, a microwave oven or a steamer. Combinations of the above are possible.

The cooking space divider is in particular an electrically operable insert part for the cooking appliance. The cooking compartment divider can be designed with or without thermal insulation. For example, the cooking space divider can be a heatable food support, e.g. a heated baking tray, act. The cooking space divider may have heating elements. In particular, the cooking space divider can provide a heater for a top heat and / or a heater for a bottom heat.

The cooking compartment divider is contacted via the electrical connection and controlled accordingly via a (stove) control. In this case, it is particularly advantageous that the cooking space divider does not require a protective conductor and thus that the electrical connection can be made in a variety of ways (for example in combination with mechanical contact elements).

In the case of the door safety circuit, which is connected in series at least partially with the electrical connection for contacting the cooking compartment divider, it may be a logical AND operation, which is at least partially perceived by a control unit. Thus, for example, a first switch of the door security circuit can be physically connected in series with the connections for the cooking space divider and a second switch of the door security circuit can be evaluated by the control unit such that the cooking space divider is only supplied with electrical energy, although this second switch displays in that the door of the cooking appliance is closed; This can be achieved by the control unit does not (or not permanently) controls the cooking space divider, unless the second switch can recognize the closed door. This is a logical AND operation of the first switch and the second switch and correspondingly also a door safety circuit with two switches, which are functionally connected in series with the aforementioned connections for contacting the cooking chamber divider.

A development is that a unit for controlling the cooking chamber divider is provided via the electrical connection.

This unit may be a heating control or a control unit of the cooking appliance. For example, a heating power of an inserted cooking chamber divider can be adjusted by means of pulse width modulation of such a unit become. The cooking space divider can be controlled separately from heating elements of the cooking chamber.

Another development is that the electrical connection is a two-pole electrical contact.

It is advantageous that the two-pole electrical contact can be arranged flexibly in the cooking chamber. In particular, due to a symmetry of the cooking space divider, it can be used in different orientations in the cooking space.

In particular, it is a development that the electrical connection is designed as at least one plug or at least one socket.

It is advantageous if each connection is designed as a plug or as a socket. In particular, a contact safety of the electrical contacts of the cooking compartment divider can advantageously be achieved thereby.

It is also a development that the door safety circuit comprises at least two switches, by means of which it can be determined whether a door of the cooking appliance is closed.

The switch may be a microswitch, a pushbutton or an electrical contact, e.g. is closed when the door of the cooking appliance is closed. Accordingly, the switch can be designed so that it is open as soon as the door of the cooking appliance is closed; Thus, the closed switch or contact indicates that the door of the cooking appliance is open. Accordingly, the open or closed state of the switch can be detected and detected by a control unit, e.g. a stove control, to be evaluated.

With the at least two switches a certain reliability of one of the switches can be ensured or can be detected by means of the control unit, a defective switch.

Furthermore, it is a development that the two switches of the door safety circuit are connected in series.

This can be achieved by the redundant design of the switch that can be determined at two independent locations, if the door is closed and only then are the electrical connections for contacting the cooking compartment divider powered. According to the invention, a control unit is provided, by means of which the door safety circuit can be evaluated and by means of which, depending on a state of the door safety circuit, the electrical connections for contacting the cooking compartment divider are supplied with power.

For example, it is advantageous if one of the switches is connected as a door safety circuit in series with an electrical connection for contacting the cooking chamber divider. The other (redundant) switch is connected directly to the control unit so that the control unit can determine the condition of the door. Thus, with the one switch the other switch can be monitored and an error condition can be detected. The error state can be displayed by the control unit and the cooking appliance can then be transferred to a safe operating state.

In particular, it is possible that in the open state the switch connected in series with the connection for contacting the cooking chamber divider is connected to the control unit and thus it can be determined that this switch is not closed. In other words, the switch can be designed as a changeover switch which is connected in the open state to the control unit and in the closed state allows a flow of current through the cooking space divider.

A next development is that at least one further switch is provided, by which it can be determined whether the cooking space divider is inserted into the cooking appliance.

For example, the (at least one) further switch can be a microswitch, pushbutton or electrical contact, which makes it possible to determine whether the cooking chamber divider has been inserted into the cooking appliance. Thus, for example, a spring contact may be provided which closes a circuit with the onset of the cooking chamber divider and thus enables the detection of the cooking space divider in the cooking appliance. Alternatively or additionally, the circuit can also be opened as soon as the cooking compartment divider has been inserted into the cooking appliance.

The additional switch or an additional redundant further switch can be connected, for example, to a stove control, which evaluates the respective state of the switch and thus can detect whether or not the cooking space divider is inserted into the cooking appliance. By several more switches for detecting the cooking chamber divider, it is possible that faulty switches can be determined.

One embodiment is that the further switch is connected in series with the door safety circuit.

In particular, at least one of the further switches is connected in series with the door safety circuit. Thus, the electrical connection for contacting a cooking chamber divider is only supplied with power, although the other switch for detecting the used cooking chamber divider indicates that the cooking space divider is inserted into the cooking appliance.

This advantageously ensures that the connections for supplying the cooking space divider are de-energized when the cooking space divider is not inserted into the oven.

An alternative embodiment is that based on the control unit and the at least one further switch can be determined whether the cooking space divider is inserted into the cooking appliance, only when the cooking space divider inserted, the electrical connections for contacting the cooking space divider are supplied with power.

In particular, it is possible that in the open state of the connected in series with the terminal for contacting the cooking chamber divider further switch is connected to the control unit and thus it can be determined that this further switch is not closed. In other words, the further switch can be designed as a changeover switch, which is connected in the open state to the control unit and in the closed state allows a flow of current through the cooking space divider.

Embodiments of the invention are illustrated and explained below with reference to the drawings.

Fig.1

ein Blockschaltbild zur Versorgung eines Garraumteilers in einem Gargerät;

Fig.2

ein schematisches Blockschaltbild mit einer Heizung für einen Garraumteiler.

Show it:

Fig.1

a block diagram for supplying a cooking space divider in a cooking appliance;

Fig.2

a schematic block diagram with a heater for a cooking space divider.

By the solution proposed here, the use of a protective conductor can be saved. For this purpose, in a cooking appliance a door safety circuit is provided which is connected in series with an electrical contact, e.g. for a cooking compartment divider, is connected.

In particular, the cooking appliance has a door, by means of which a muffle of the cooking appliance can be closed.

The electrical contacting may be at least two electrical connections for the cooking chamber divider, e.g. in the form of a plug or a socket, act. About these connections, the cooking compartment divider is supplied with power; a separate protective conductor is not needed for the cooking compartment divider.

Based on the door safety circuit can be ensured that the electrical supply of the cooking chamber divider is interrupted when the door of the cooking appliance is opened.

In particular, the door safety circuit may comprise a switch, by means of which the state of the door (open or closed) can be determined. Furthermore, a further switch can be arranged in series with this switch, by means of which also the state of the door (open or closed) can be determined. If one of the switches is defective (for example, permanently closed), the circuit is interrupted by the other switch, thus ensuring that the circuit to the cooking chamber divider is interrupted when the door is opened.

It should be noted that the switches mentioned here may also be buttons or other contacts (for example relays, microswitches, spring contacts, etc.).

Optionally, the connections of the cooking compartment divider can be de-energized if the cooking space divider is not inserted into the muffle. For this purpose, at least one switch can be provided, which is closed if the cooking space divider into the muffle is used. Only then (and if the door is closed) are the connections of the cooking compartment divider supplied with power. Also, the switch for detecting whether the cooking chamber divider is inserted into the muffle, can be designed redundant. Only if both switches indicate that the cooking compartment divider is inserted in the muffle, this is also supplied with power (if the door of the cooking appliance is closed).

Fig.1 shows a block diagram for supplying a cooking space divider 101 in a cooking appliance. The cooking space divider 101 can be electrically connected via contacts 102, 103 (eg in the form of a socket or in the form of, for example, side contact plugs or contact sockets) in the cooking appliance.

In the example of Fig.1 a cooker control 106 (PEC, Protective Electronic Circuit) is provided, for example, with at least one processor, which is controlled by a suitable software that meets certain safety-related requirements. Furthermore, a hardware of the hearth control 106 may be configured redundantly, so that an undesired condition caused by a malfunction can be largely excluded.

A door switch 104 and a door switch 105 detect whether the door of the cooking appliance is closed.

Furthermore, switches 107 and 108 are provided, which are closed when the cooking space divider 101 is inserted into the cooking appliance.

A clock relay 109 is controllable via the hearth control 106 and can be used e.g. also be used for controlling the heating power of the cooking chamber divider 101 (for example by means of pulse width modulation). Furthermore, a main switching relay 110 is provided that can be activated or deactivated by the hearth controller 106.

In the Fig.1 shown circuit is supplied via terminals 111 and 112 with electrical power (eg via a mains AC voltage). The terminals 111 and 112 are connected to the oven controller 106. Furthermore, a series connection of the clock relay 109, the switch 107, the contact 102, the (possibly used) cooking space divider 101, the contact 103, the door switch 104 and the main switching relay 110 is provided between the terminals 111 and 112. If the clock relay 109, the switch 107, the door switch 104 and the main switching relay 110 are closed, is the inserted cooking chamber divider via the terminals 111 and 112 supplied with electrical power.

If the main switching relay 110 is open, this switching position can be detected via an input 113 of the hearth control 106. Accordingly, the door switch 104 is connected to an input 114 of the oven controller 106 in the open switching state. The open switching state of the switch 107 is via an input 115 of the oven control 106 and the open switching state of the clock relay 109 is detected via an input 116 of the oven control 106.

Based on the inputs 113 to 116 can thus be determined, in part depending on the switching states of the other switches, whether the individual switches are open or closed.

Both terminals of the switch 108 are connected to the oven controller 106. Also, both terminals of the door switch 105 are connected to the hearth control 106. Thus, the oven controller 106 may determine if the switch 108 is open or closed. Likewise, the oven controller 106 may determine if the door switch 105 is open or closed.

In the Fig.1 shown circuit can ensure based on the redundant door switches 104 and 105 that the cooking space divider 101 is only supplied with power when the door is closed. Even faulty door switches are detectable. For example, a malfunctioning in the closed state door switch 105 can be detected by briefly the main switch relay 110 is actuated and thus a (correctly) open door switch 104 is detected via the input 114. Thus, the stove controller 106 can output a fault state "door switch defective" and change to a safe operating state. Conversely, the faulty door switch 104 (permanently closed) can be detected by briefly closing the main switch relay and detecting the state of the door switch 104 at the input 114 as being closed (the state of the main switch 110 does not change the input 114, although the door switch 105 is open). Even then, the stove control 106 can output the error state "door switch is defective" and change to the safe operating state.

Regardless of the switching state of the door switch 104, 105 it is also ensured that the contacts 102 and 103 in the case of the unused cooking compartment divider 101st are switched off. This is done by means of the switches 107 and 108, which are respectively closed when the cooking space divider 101 is properly inserted into the cooking appliance.

If the switch 108 is defective (i.e., permanently closed), this can be determined via the input 115 of the oven controller 106: When the clock relay 109 is momentarily closed, the open state of the switch 107 can be detected. Thus, it can be determined for the hearth control 106 that not both switches 107 and 108 indicate the same state and thus an error state "cooking space divider recognition is defective" is present. Accordingly, this error can be displayed and changed to a safe operating state. If the switch 107 is defective (i.e., permanently closed), this can also be determined by momentarily closing the clock relay 109. Thus, in this case, no signal change is sensed at the input 115 of the oven controller 106, although the switch 108 is (correctly) open. Thus, the error state "cooking space divider detection is defective", the stove control 106 can switch to the safe operating state.

As in Fig.1 is displayed, the hearth control 106 may additionally monitor the states of the clock relay 109 and the main switching relay 110 by means of the inputs 116 and 113 and thus ensure that a triggering of the respective switch actually leads to the intended action or a defect of the clock relay 109 and / or or the main switch relay 110 are detected.

Fig.2 shows a schematic block diagram with a heater 201 for a cooking space divider, wherein when inserted cooking chamber divider, a switch 202 is closed. Via terminals 204 and 205, a mains voltage is applied, which feeds from the terminal 204 via a fuse 206 and a node 210, a hearth control 203. The port 205 is also connected to the hearth control 203.

Furthermore, two door switches 208 and 209 are provided, which are connected in series. The door switch 208 is connected to the open door of the cooking appliance via a resistor 207 to the node 210. If the door switch 208 is closed, it connects the door switch 209 to the heater 201. The door switch 209 is open when the door is open and connects the door switch 208 to the connection 205 when the door is closed.

Furthermore, a relay 211 is provided, which can be controlled by the stove control 203. The relay 211, the switch 202, the heater 201, the door switch 208 and the door switch 209 are connected in series with each other.

For example, if the door switch 208 is in the closed position (in which the heater 201 is connected to the door switch 209), the door switch 209 ensures that the heater 201 is not connected to the mains voltage terminal 205. On the other hand, when the door switch 209 is in the closed position, when the door is opened, the door switch 208 is connected to the mains voltage terminal 205, thereby connecting to the resistor 207 and the node 210. A current then flows from the terminal 204 of the mains voltage via the fuse 206, and the resistor 207 to the terminal 205 of the mains voltage. The resistor 207 is dimensioned so that the current is sufficient to trigger the fuse 206 if necessary. As a result, the hearth control 203 is de-energized and the clock relay 211 switches off. In particular, there are no special safety requirements for the hearth control 203 (i.e., no PEC needs to be provided).

The advantage of the solutions presented here is in particular to obtain the greatest possible degree of freedom in the design of the cooking chamber divider and / or the electrical contacts for connecting the cooking chamber divider. In particular, a space requirement of the electrical contacts can be minimized because no protective conductor connection must be provided.

The switches mentioned here can also be designed as pushbuttons, relays, microswitches or other switchable components or (movable) contacts. Creepage distances of (at least) 4 mm for a basic insulation and of (at least) 3.2 mm for a functional insulation are preferably maintained in accordance with a degree of contamination. An air gap to the protective earth is preferably at least 1.5mm.

LIST OF REFERENCE NUMBERS

101

Garraumteiler

102

Contact (connection) for the cooking compartment divider 101

103

Contact (connection) for the cooking compartment divider 101

104

door switch

105

door switch

106

Herd control

107

Switch (for detecting whether the cooking space divider 101 is inserted in the cooking appliance)

108

Switch (for detecting whether the cooking space divider 101 is inserted in the cooking appliance)

109

timing relay

110

Main switch relay

111

Connection (AC mains voltage)

112

Connection (AC mains voltage)

113

Input of the stove control

114

Input of the stove control

115

Input of the stove control

116

Input of the stove control

201

Heating for cooking compartment divider

202

Switch (for detecting whether the cooking compartment divider is inserted in the cooking appliance)

203

Herd control

204

Connection (AC mains voltage)

205

Connection (AC mains voltage)

206

fuse

207

resistance

208

door switch

209

door switch

210

node

211

timing relay

Claims (8)

1. A cooking appliance with a door safety circuit (104, 105; 208, 209), on the basis of which it can be defined whether a door of the cooking appliance is closed and which is connected at least partially in series with an electrical connection (102, 103) for the purpose of making contact with a cooking compartment divider (101), and having at least one further switch (107, 108; 202) which is connected in series with the door safety circuit (104, 105; 208, 209), on the basis of which it is determined whether the cooking compartment divider (101) is inserted into the cooking appliance, characterized in that a control unit (106; 203) is provided, wherein by means of the control unit (106, 203), the door safety circuit (104; 105; 208, 209) is evaluated and by means of the control unit (106, 203) as a function of a status of the door safety circuit (104, 105; 208, 209), the electrical connections (102, 103) are supplied with current for the purpose of making contact with the cooking compartment divider.
2. The cooking appliance as claimed in claim 1, with a unit (106; 101) for activating the cooking compartment divider by way of the electrical connection (102, 103).
3. The cooking appliance as claimed in one of the preceding claims, in which the electrical connection (102, 103) is a two-pole electrical contact.
4. The cooking appliance as claimed in one of the preceding claims, in which the electrical connection (102, 103) is designed as at least one plug or as at least one socket.
5. The cooking appliance as claimed in one of the preceding claims, in which the door safety circuit (104, 105; 208, 209) comprises at least two switches (104, 105; 208, 209), on the basis of which it can be determined whether a door of the cooking appliance is closed.
6. The cooking appliance as claimed in claim 5, in which the two switches (208, 209) of the door safety circuit are connected in series.
7. The cooking appliance as claimed in claim 6, in which on the basis of the control unit (106; 203) and the at least one further switch (107, 108; 202) it can be determined whether the cooking compartment divider is inserted into the cooking appliance, wherein only when the cooking compartment divider is inserted are the electrical connections for the purpose of making contact with the cooking compartment divider supplied with current.
8. The cooking appliance as claimed in one of claims 6 or 7, in which the control unit (106; 203) is a cooker control equipped with a processor, which is activated by suitable software, which corresponds to certain safety-relevant requirements.

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