EP1669678B1

EP1669678B1 - Electric oven and pyrolysis controlling method for the same

Info

Publication number: EP1669678B1
Application number: EP20050111093
Authority: EP
Inventors: Young Chul Kim
Original assignee: LG Electronics Inc
Current assignee: LG Electronics Inc
Priority date: 2004-12-08
Filing date: 2005-11-22
Publication date: 2008-10-15
Anticipated expiration: 2025-11-22
Also published as: AU2005242178B2; DE602005010376D1; EP1669678A1; AU2005242178A1

Description

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to an electric oven, and more particularly, to an electric oven according to the preamble of claim 12 having a pyrolysis function and a method according to the preamble of claim 1 for controlling the same in order to protect components inside the oven to increase their reliability.

Description of the Related Art

An oven is a widely used cooking apparatus that heats food inside its cavity at high temperature.
An oven range incorporates an oven and a heating plate disposed on top of the oven on which cooking containers are placed. The containers are heated by a range coupled to the heating plate so that food contained in the containers is cooked. Oven ranges are categorized into two types according to their heating source, that is, a gas oven range and an electric oven range.
Gas oven ranges are usually powered by gas that heats a plurality of burners, and electric oven ranges use electricity to heat ceramic, sheathe, halogen, or other types of heaters.
Electric oven ranges are able to simultaneously heat food not only from the bottom but from all sides, thus providing a faster cooking time and heating efficiency than gas oven ranges. Additionally, because electricity is used, electric oven ranges are safer than their gas counterparts, and are therefore, very popular. Electric oven ranges are identical to electric ovens, except for a range added at the top.
During prolonged use of an electric oven range, smoke residue from cooking meats and other foods is deposited on the cavity's inner walls. Because the smoke is from burnt food, it contains grease and other impurities that are difficult to remove from the inner walls of a cavity without using a grease cleaner. Thus, it is inconvenient for a user to periodically have to clean the interior of an oven cavity with cleaning agents.
In order to alleviate this inconvenient aspect of ovens, a pyrolysis function that applies maximum heat to an oven cavity to burn and remove grease deposits can be used.
During the use of the pyrolysis function, however, because the inside of the oven cavity is heated to extremely high temperatures, the racks, brackets, and other components inside the cavity can be damaged. When the pyrolysis function is used, racks, brackets, and other loose items in the cavity must be removed.
However, it is easy for a user to forget to remove the components prior to activating the pyrolysis function, and therefore, it is common that components that aren't duly removed prior to pyrolysis are damaged during the process.
Although technology exists that emits audible signals to remove racks prior to pyrolysis, if the racks are not removed, there is no way of checking their presence or lack thereof, so that the interior components can still be damaged by high temperatures during pyrolysis.
DE 19954470 A1 discloses an electric oven including a pyrolysis function and a method of controlling such electric oven on which the preamble portions of claim 1 and 12 are based. This prior art electric oven is provided with detection devices for automatically detecting the presence of telescoping supports within the cavity. The pyrolysis is only started by a control unit of the oven if the result of this detection is negative. The detection devices are formed as electrical switches activated by the telescoping supports.

SUMMARY OF THE INVENTION

Accordingly, the present invention is directed to an electric oven and to a controlling method for the same that substantially obviate one or more problems due to limitations and disadvantages of the related art.
An object of the present invention is to provide an electric oven having a pyrolysis function and a controlling method for the same that protect components inside the oven when the pyrolysis function is used.
Another aspect of the present invention is to provide an electric oven that allows normal operation of its pyrolysis function at all times by separately installing pyrolysis-related components.
A further aspect of the present invention is to provide an electric oven capable of sensing cases where a user forgets to remove cooking components from inside the oven prior to using the pyrolysis function, and operating accordingly.
Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.
To achieve these objects and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, there is provided electric oven as defined in claim 12 and a method of controlling an electric oven as defined in claim 1. Preferred embodiments of the method and of the oven are defined in the dependent claims.
The pyrolysis function of an electric oven range according to the present invention is able to operate reliably and safely. Furthermore, because it can issue warnings to a user, the pyrolysis function can operate under normal conditions.
It is to be understood that both the foregoing general description and the following detailed description of the present invention are exemplary and explanatory and are intended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this application, illustrate embodiment(s) of the invention and together with the description serve to explain the principle of the invention. In the drawings:

Fig. 1 is a perspective view of a portion of an electric oven range according to the present invention;
Fig. 2 is a perspective view of a cavity of an electric oven range similar to the present invention;
Fig. 3 is a block diagram showing the structure of an electric oven range that has a pyrolysis function similar to the present invention;
Fig. 4 is a flowchart showing the method of controlling the pyrolysis function of an electric oven range similar to the present invention;
Fig. 5 is a perspective view of a portion of a cavity of an electric oven range that has a pyrolysis function according to an embodiment of the present invention;
Fig. 6 is a block diagram showing the structure of an electric oven range according to the embodiment of the present invention; and
Fig. 7 is a flowchart showing the method of controlling the pyrolysis function of an electric oven range according to the embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to an example of an oven range which is similar to the present invention but does not form part of the invention and to a preferred embodiment of the present invention, which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers will be used throughout the drawings to refer to the same or like parts.

EXAMPLE

Fig. 1 is a perspective view of an electric oven range according to the present invention, where the electric oven range 1 is a structure defined by 6 surfaces.
The electric oven range 1 includes a countertop 10 for placing cooking containers on top to heat them and cook food within, a control panel 20 disposed at the rear of the countertop 10 and extending upward for controlling the operation of the electric oven range 1, an oven 30 disposed below the countertop 10 for cooking food within using heat convection, and a drawer 40 disposed below the oven 30 for basic cooking and storage.
The countertop 10 forms the top portion of the electric oven range 1 and has a plurality of infrared, halogen, or other types of heaters formed thereon.
Ceramic glass 14 that transmits the infrared or other heat type is formed over the electric burners 12 formed on the countertop 10 to seal them.
A control panel 20 is disposed at the rear of the countertop 10 extending upward for controlling the operation of the electric oven range 1. At one area of the front of the control panel 20 is a display 22 for showing the operating mode, cooking time, etc. of the electric oven range 1, and to the sides of the display 22 are a plurality of control knobs 24 for a user to control the operation of the electric oven range 1 with.
An oven 30 is disposed beneath the countertop 10. The oven 30 heats a plurality of heating elements to induce heat convection to cook food inside the space sealed by an oven door 50 disposed at the front of the oven 30, the door formed to selectively open and shut.
A convection fan is installed inside the oven for forcefully cooling the plurality of heating elements and the heat inside the oven 30, aiding in evenly cooking food.
Also, formed at the front of the oven door 50 is a handle 52 that a user can easily grasp to open and close the oven door 50; and formed through the oven door 50 is a see-through window 54 formed of heat-resistant glass allowing a user to view the inside of the oven from the outside.
The opening and closing drawer 40 formed below the oven 30 includes a separate heater for warming cooked food or cooking smaller morsels of food and a shelf-type structure for storing cooking containers and food.
A detailed description of the pyrolysis function during operation of an electric oven range will be made below.
Fig. 2 is a perspective view of a portion of a cavity of an electric oven range which is similar to the present invention, but does not form part of it.
Fig. 2 shows a cavity 452 for holding food therein, a rack 424 resting inside the cavity 452 for placing foods on, and a checking portion fixed to an inner surface of the cavity 452 for removal by a user before implementing the pyrolysis function.
Before a user implements the pyrolysis function, the checking portion is used. The checking portion includes a checking screw 431 protruding outward from components that need to be removed from the cavity, and a sensor (not shown) disposed to the inside of the checking screw 431 on the surface of the cavity 452. When a user decides to use the pyrolysis function and removes the checking screw 431, the sensor senses the removal and allows the pyrolysis function to be carried out. Should a user implement the pyrolysis function by mistakenly pressing the command buttons, and the checking screw 431 is not removed, the pyrolysis function may be programmed not to function. In other words, an unintended operation of the electric oven range through mistaken command inputs can be avoided.
The checking screw 431, however, is only an exemplary component of the checking portion for a user to utilize, which may be replaced by another part not necessarily in the form of a screw. For example, a bar, nut, or any number of devices that can be manipulated by a user may be used in lieu of the checking screw 431. However, the checking screw 431 is used again in the explanation below for the sake of convenience.
Fig. 3 is a block diagram showing the structure of an electric oven range that has a pyrolysis function which is similar to the present invention but does not form part of it.
Referring to Fig. 3, the electric oven range having a pyrolysis function includes: an key input unit 720 for allowing the user to input commands, a sensor unit 710 for sensing whether the rack is present inside the oven and implementing the pyrolysis function when the user selects the pyrolysis mode through the key input unit 720, a temperature sensor unit 730 for detecting the temperature inside the oven, a control unit 740 for selectively controlling the temperature inside the oven according to feedback from the sensor unit 710, a display unit 760 for displaying the operational status of the oven according to a control signal from the control unit 740, and a load driver unit 750 for driving load components according to control signals from the control unit 740.
Here, the sensor unit 710 is intended to implement the pyrolysis function and includes the checking screw 431 and sensor (not shown) in Fig. 2.
An explanation will now be given on the operation of the above electric oven range having a pyrolysis function.
The user turns on the power by pressing a power button on the key input unit 720, and selects a desired cooking setting by manipulating the control panel. The control unit 740 carries out the inputted cooking setting. Heat is emitted from elements through driving signals from the load driver unit 750, and the temperature sensor unit 730 senses the temperature inside the cavity in order to control the operation of the electric oven range.
When the user selects the pyrolysis mode using the key input unit 720, the control unit 740 determines if conditions allow the implementation of the pyrolysis mode through feedback from the sensor unit 710.
In one scenario, a second sensor unit 712 determines if the checking screw 431 for pyrolysis has been removed, and the control unit 74 controls the load driver unit 750 to implement the pyrolysis function.
In another scenario, if it is sensed that the checking screw 431 for pyrolysis has not been removed, the control unit 740 sends a control signal to the display unit 760 instructing it to display a message indicating that the pyrolysis checking screw 431 should be removed. Of course, the load driver unit 750 does not function at this time.
The display unit 760 is to be understood in the general sense of a signalling unit for signalling to the user the operational status according to the control signal from the control unit. It can be a commonly known display screen capable of indicating symbols and/or characters or any arrangement of lights (LEDs) or other commonly known means suitable to indicate an operational status.
In this manner, when a user unintentionally sets the pyrolysis mode by mistakenly pressing keys, the pyrolysis mode may be cancelled by pressing a cancellation button.
By thus preventing unintentional operation of the pyrolysis mode, power is saved, and the level of user safety is elevated. Below, a detailed explanation on the method of controlling the pyrolysis function of the electric oven range which is similar to the present invention but does not form part of it will be given with reference to Fig. 4.
Fig. 4 is a flowchart showing a method of controlling the pyrolysis function of an electric oven range similar to the present invention.
Referring to Fig. 4, after power is turned on in step S101, the control unit determines whether the pyrolysis mode has been selected in step S102. Next, if the pyrolysis mode has been selected, as determined in step S102, it is determined if the pyrolysis checking screw 431 is present in step S103.
If the checking screw is determined to be present in step S103, a message indicating that the checking screw should be removed is displayed in step S104. On the other hand, if the checking screw is found not to be present in step S103, the pyrolysis function is carried out in step S105. The plurality of heat sources such as heating elements inside the cavity are heated to maximum so that the temperature inside the cavity becomes extremely high.
When the pyrolysis mode is completed in step S106, a message is displayed indicating its completion in step S107.
If, in step S102, it is determined that the user has not selected the pyrolysis mode, other modes selected by the user are implemented in step S108.
In the above description of a controlling method for pyrolysis, the pyrolysis checking screw needs to be removed in the electric oven range in order for the pyrolysis mode to function properly. However, the controlling method can also prevent the pyrolysis mode from operating if a user sets the pyrolysis mode by accidentally pressing buttons; and furthermore, if a user sets the pyrolysis mode without first removing the racks, brackets, and cooking containers from the cavity, the controlling method can prevent the electric oven range from operating according to the user's input commands, thereby preventing damage to the racks and like components.
Advantages of the electric oven range having the above pyrolysis function and the controlling method for the oven will now be addressed.
First, because the checking screw (for checking the operation of the pyrolysis mode when the mode is set) is formed to check if the rack is present in the oven, the pyrolysis mode is not executed if the rack is present, so that the rack and other interior components are protected.
Second, by notifying a user of the operation status of pyrolysis, the user can readily perceive the situation.
Third, even if a user carelessly uses the electric oven range, the oven will operate safely.

EMBODIMENT

The embodiment of the present invention has many similarities with theabove example, and includes two checking portions, being the pyrolysis checking screw and an additional rack screw for checking if the rack has been removed. In explaining the embodiment, only the characteristics thereof which differ from those of the above example will be explained, and characteristics corresponding to those of the above example, while omitted, should be understood to be the same as described in the example. Accordingly, the same reference numerals will be used for parts identical to those in the example.
Fig. 5 is a perspective view of a portion of a cavity of an electric oven range that has a pyrolysis function according to a embodiment of the present invention, and Fig. 6 is a block diagram showing the structure of an electric oven range according to the embodiment of the present invention.
Referring to Figs. 5 and 6, the cavity 452 of the electric oven range according to the present invention includes a pyrolysis checking screw 431 for a user to purposely remove before implementing the pyrolysis function, and a rack screw 432 for securing the rack 424. The rack screw 432 also has a sensor provided therewith for double-checking if the rack 424 has been removed by checking if the rack sensor 432 has been removed. Also, because the rack screw 432 functions to secure the rack 424, the latter can only be removed by removing the former.
Furthermore, the sensor unit 710 includes a second sensor 712 for determining whether the pyrolysis checking screw 431 has been removed, and a first sensor 711 for determining whether the rack screw 432 has been removed, as shown in Fig. 6. Because the first sensor 711 determines whether the rack screw 432 has been removed, it more reliably prevents damage to the rack 424.
The controlling method of the pyrolysis function of the electric oven range according to the embodiment of the present invention will be described below.
Fig. 7 is a flowchart showing the method of controlling the pyrolysis function of an electric oven range according to the embodiment of the present invention.
Referring to Fig. 7, after the power to the electric oven range has been turned on and detected in step S201, the control unit determines whether the pyrolysis mode has been selected in step S202.
If the pyrolysis mode has been selected according to step S202, the control unit determines if the pyrolysis checking screw 431 is present in step S203. If the checking screw 431 is found to be present in step s203, a message indicating that the screw must be removed is outputted in step S204.
On the other hand, if the checking screw 431 is found not to be present in step S203, the pyrolysis function is carried out in step S205 according to the settings.
Additionally, the control unit determines in step S206 if the rack screw 432 is present in order to determine if the rack is present. If the rack is found to be present in step S206, a first temperature setting for the inside of the cavity is maintained in step S207, the first temperature setting being approximately 250°, which will not cause damage to the rack.
When pyrolysis in step S208 at the first temperature setting is completed, "partial pyrolysis operation" is outputted in step S209. When the user views this outputted message, (s)he will realize that partial pyrolysis was implemented due to the presence of the rack in the oven.
If the rack is determined to not be present in step S206, a second temperature setting is maintained inside the cavity in step S210 for full implementation of pyrolysis. The second temperature setting is approximately 450°, which can damage the rack. However, because the rack has already been removed from the cavity, no damage is incurred.
When the operation is completed in step S211, the message, "normal pyrolysis operation" is displayed in step S212. Upon seeing this message, the user realizes that the pyrolysis function has ended.
If the pyrolysis mode has not been selected by the user as sensed in step S202, other command settings inputted by the user are carried out in step S213.
In this embodiment, if the pyrolysis mode is selected, but the rack is not removed, the pyrolysis function is implemented at a first temperature setting for the oven's interior, so that partial pyrolysis is performed in order to partially remove food deposits in the oven.
In this embodiment, if a user mistakenly sets the electric oven range in pyrolysis mode or fails to remove the rack before this setting, the oven can still operate safely.
Also, because the system requires a double-check, safe operation of the oven is reinforced.
In addition, because the pyrolysis function can be carried out with the rack present, the oven is more convenient to use.
Furthermore, because the display outputs messages, a user can more readily check the status of pyrolysis operation.
While the described embodiment of the present invention addresses an electric oven range, it is equally applicable to an oven without a range.

Claims

A method of controlling an electric oven for implementing a pyrolysis function to clean an interior of a cavity (452), the controlling method comprising:
(a) determining if a first checking portion (431,712) has been manipulated by a user when a pyrolysis mode is selected; (a1) providing a message to manipulate the first checking portion (431,712) if it is determined that the first checking portion (431,712) has not been manipulated; and

(a2) conducting a pyrolysis if it is determined that the first checking portion (431,712) has been manipulated;
characterized in that the method comprises the steps of:

(b) determining if a second checking portion (432,711) has been manipulated by a user when pyrolysis is conducted; and

(b1) conducting the pyrolysis at a first temperature setting if it is determined that the second checking portion (432,711) has not been manipulated, and (b2) conducting the pyrolysis at a second temperature setting if it is determined that the second checking portion (432,711) has been manipulated.
The controlling method according to claim 1,
wherein the message is visually displayed.
The controlling method according to claim 1 or 2,
wherein said first and second checking portions (431, 712; 432, 711) are provided in the interior of the cavity (452) that can be removed by a user and said manipulation comprises removing the checking portions (431,432).
The controlling method according to any one of the preceding claims, further comprising displaying a message signaling completion after the pyrolysis has been completed.
The controlling method according to any one of the preceding claims, wherein the second checking portion (432,711) serves to fix a removable component (424) inside the cavity (452).
The controlling method according to any one of the preceding claims, wherein, when it is determined that the first checking portion (431,712) is not manipulated, the pyrolysis is not conducted and a message is displayed.
The controlling method according to any one of the preceding claims, wherein the pyrolysis is conducted at the second temperature setting at a temperature required for normal pyrolysis when it is determined that both the first and second checking portions (431,712;432,711) are manipulated.
The controlling method according to claim 7, further comprising displaying a message indicating that the pyrolysis mode was conducted at the temperature required for normal pyrolysis.
The controlling method according to any one of the preceding claims in combination with claim 5, wherein the pyrolysis is conducted at the first temperature setting at a lower temperature that does not inflict damage to the removable component (424) inside the cavity (452) when it is determined that the first checking portion (431,712) is manipulated and that the second checking portion (432,711) is not manipulated.
The controlling method according to claim 9, further comprising displaying a message indicating that partial pyrolysis was conducted after completion of the pyrolysis at the lower temperature.
The controlling method according to any one of the preceding claims, wherein the checking portion(s) include(s) a screw (431,432) to be operated rotationally and the required manipulation comprises removing the screw (431,432).
An electric oven comprising:
a key input unit (720) for inputting commands;

a sensor unit (710) including a first checking portion (431,712) and a second checking portion (432,711) for sensing if a user has performed a predetermined required manipulation when a pyrolysis mode is selected through the key input unit (720) ;

a control unit (740) for selectively conducting a pyrolysis according to a feedback from the sensor unit (710); and

a signaling unit (760) for signaling to the user an operational status according to a control signal from the control unit (740);

wherein said control unit (740) is adapted to conduct a pyrolysis if a pyrolysis mode is selected and if it has determined that the first checking portion (431,712) has been manipulated by a user,

characterized in that said control unit (740) is adapted to conduct the pyrolysis at a first temperature setting if it is determined that the second checking portion (432,711) has not been manipulated, and to conduct the pyrolysis at a second temperature setting if it is determined that the second checking portion (432,711) has been manipulated.
The electric oven according to claim 12, wherein said first and second checking portion (431,712;432,711) are provided in an interior of a cavity (452) that can be removed by a user and said predetermined required manipulation comprises removing the checking portions (431,432).
The electric oven according to claim 13, wherein the checking portion(s) comprise(s) a screw (431,432) provided on an inside wall of the cavity (452) and the required manipulation comprises removing the screw (431,432).
The electric oven according to claim 12, 13 or 14, wherein the signaling unit comprises a display unit (760) adapted to display a message requesting a manipulation of the first checking portion (431,712) when the first checking portion (431,712) has not been manipulated.
The electric oven according to any one of claims 12 to 15, wherein the second checking portion (432,711) includes a sensor (711) for sensing a manipulation of an element serving to fix a removable component (424) inside a/the cavity (452) of the oven.
The electric oven according to any one of claims 12 to 16, wherein the signaling unit (760) is adapted to output a completion message after the pyrolysis has been completed.