EP2638328A1

EP2638328A1 - An oven wherein the cooking time is shortened

Info

Publication number: EP2638328A1
Application number: EP11782131.4A
Authority: EP
Inventors: Asli Saime Kayihan; Ahmet Onder Fesligil; Nilay Yalcinkaya; Kemal Sarioglu
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2010-11-11
Filing date: 2011-11-10
Publication date: 2013-09-18
Anticipated expiration: 2031-11-10
Also published as: EP2638328B1; WO2012062864A1

Abstract

The present invention relates to an oven (1 ) comprising an oven cavity (2) wherein trays containing foods to be cooked are placed, a door (3) allowing access into the oven cavity (2), a heater (4) and wherein the cooking time is shortened.

Description

AN OVEN WHEREIN THE COOKING TIME IS SHORTENED

The present invention relates to an oven wherein the cooking time is shortened.
In ovens, the oven cavity has to reach a certain temperature according to the type of food, so that the foods placed in the oven cavity are cooked well. In the period of time required for the oven cavity to reach the ideal temperature, the heat distribution in the oven cavity cannot be homogeneous depending on the location of the heater.
Furthermore, the oven cavity has to be preheated for the foods that should rise and the food is placed into the oven cavity that has reached the desired temperature. However, the door of the oven is opened when food is desired to be placed in the oven cavity that has reached the desired temperature and the oven cavity loses heat by the mixing of the air from the exterior environment. The heat loss from the preheated oven cavity during placing of the food results in presence of insufficient heat for rising the food and hence not getting the desired result. Furthermore, more energy is consumed since the heated air mixes with the exterior environment.
In ovens having automatic cooking programs, the foods have to be placed in the oven cavities that are at room temperature. The humidity and weight sensors detecting the type and amount of foods, included in the ovens having automatic cooking feature, provide detection of for how long and at which temperature the foods have to be cooked before the heater is operated. However, a long time period passes until the oven cavity, starting to heat by the actuation of the heaters after the cooking algorithm is determined, reaches the desired temperature.
In the state of the art International Patent Document No. WO2007054917, an oven is explained, which provides the cooking of pastries like cakes that tend to rise during the cooking, that controls the rising of the surface of the cake by means of a sensor and provides to crisp the upper surface of the pastry to be cooked at the maximum rise level.
In the state of the art International Patent Document No. WO2010076149, an oven is explained, comprising a casing, a cooking chamber which is located inside this casing and in which the trays containing the foods to be cooked are placed, a heater which provides the air in the oven cavity to be heated, at least one fan which is located at the side where the rear wall of the casing is located, and which moves the heated air, a fan compartment wherein the heater and the fan are disposed, a fan covering plate which separates the cooking chamber and the fan compartment inside the casing, and more than one opening located on the fan covering plate and which provides the air activated by the fan to be transmitted to the cooking chamber and wherein a homogenous cooking is provided by transmitting the air into the cooking chamber through the openings in the desired direction.
The aim of the present invention is the realization of an oven wherein the cooking time is shortened and heat loss is decreased.
The oven realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a door separating the oven cavity from the exterior environment, a heater and a compartment, having a separator between itself and the oven cavity, heated when the separator is closed and that transfers heat into the oven cavity when the separator is opened. By means of the compartment, defining a space separate from the oven cavity, being heated independently from the oven cavity, heat loss does not occur when the door is opened for placing foods into the oven cavity. Consequently, the cooking time is shortened and energy consumption is minimized.
In an embodiment of the present invention, the oven comprises a movement mechanism that provides the separator to be closed and opened. The movement mechanism provides the separator to remain closed before the cooking process and thus the compartment is heated by the heater. Afterwards, the separator opens by the movement mechanism being actuated and the air heated in the compartment is provided to flow into the oven cavity.
In an embodiment of the present invention, the compartment is monitored by a control unit for providing the compartment to reach a predetermined temperature. The control unit provides the separator to remain closed until reaching the compartment temperature prerecorded in its memory by the producer or the user.
In an embodiment of the present invention, the control unit provides the compartment temperature to be above the cooking temperature by an amount predetermined by the producer or the user so that the oven cavity reaches the required cooking temperature. For performing this, the control unit detects the compartment temperature and provides the heater to operate until reaching the determined temperature.
In an embodiment of the present invention, placement of food to be cooked in the oven cavity is detected by means of a sensor, another sensor detects whether the door is closed, and afterwards the separator is allowed to open.
In another embodiment of the present invention, the compartment is separated from the oven cavity by a wall. More than one separator is disposed on the wall, and the separators, when opened, enable the heat of the compartment to reach the oven cavity.
In another embodiment of the present invention, the separator is produced from shape memory material that changes shape to shift to the open or closed position when electricity or heat is applied thereon. The shape memory material is in form of, for example, a plate that expands or contracts when electricity is applied. Or the shape memory material is in form of a plate that bends or changes length when the compartment is heated. Consequently, the separator changes shape as predetermined by the producer and shifts to the open or closed position by itself.
In an embodiment of the present invention, the heater and/or the fan is situated inside the compartment. After the compartment reaches the determined temperature, the air blown by the fan fills into the oven cavity quickly upon opening of the separator. The hot air moved by the fan disperses homogeneously inside the oven cavity.
In another embodiment of the present invention, the separator is pivotally mounted to the side wall of the oven. The separator that is vertical to the side wall when in the closed position separates the compartment from the oven cavity. The separator is folded over the side wall in the open position.
In an embodiment of the present invention, the compartment is situated inside the oven cavity.
In another embodiment of the present invention, the user provides the separator to be opened/closed by means of a button.
The foods that are intended to rise should start cooking in an environment that has previously reached a certain temperature. Therefore, the oven cavity has to be heated before the cooking process begins. This process is called preheating. By means of the present invention, the compartment is heated with the heater and the food starts cooking at the desired temperature by the heat dispersed into the oven cavity when the separator is opened. Consequently, the preheating time is shortened. By means of some of the embodiments, the user does not have problems with the cooking quality even if the food is placed into the oven when it is cold. Heating only the compartment, having a small volume, instead of the whole oven provides time and energy advantage.
An oven realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 – is the perspective view of an oven of the present invention.
Figure 2 – is the sideways schematic view of the oven in an embodiment of the present invention.
Figure 3 – is the sideways schematic view of the oven in another embodiment of the present invention.
Figure 4 – is the sideways schematic view of the oven in yet another embodiment of the present invention.
Figure 5 – is the front schematic view of the oven in another embodiment of the present invention.
The elements illustrated in the figures are numbered as follows:

Oven
Oven cavity
Door
Heater
Compartment
Separator
Control unit
Movement mechanism
Intermediate wall
Fan
Side wall
Button

The oven (1) comprises an oven cavity (2) wherein trays containing foods to be cooked are placed, a door (3) allowing access into the oven cavity (2) and at least one heater (4) (Figure 1).
The oven (1) of the present invention comprises a compartment (5) having air communication with the oven cavity (2) and at least one separator (6) that prevents air flow between the oven cavity (2) and the compartment (5) when closed, allowing passage of air from the compartment (5) into the oven cavity (2) when opened (Figure 2).
The foods that have to rise should start cooking in an environment with a certain temperature. Therefore, the oven cavity (2) is not heated slowly when there is food therein that is intended to rise. The food to be cooked is placed into the oven cavity (2) and the door (3) is closed. There is no air communication between the compartment (5) and the oven cavity (2) while the separator (6) is closed and the compartment (5) is heated by operating the heater (4). After the compartment (5) is heated, the separator (6) is opened and the air heated in the compartment (5) disperses into the oven cavity (2). The air heated in the compartment (5) is provided to pass into the oven cavity (2) when the separator (6) is opened. Thus, the food placed in the oven cavity (2) heats up quickly and starts cooking at the required temperature. Thus, there is no need to place the food in the oven cavity (2) by opening the door (3) when the oven cavity (2) reaches the desired temperature, the temperature of the oven cavity (2) does not fall by mixing with the exterior environment temperature since the door (3) is not opened. After being placed in the oven cavity (2) at room temperature, the food that is intended to raise is cooked in the oven cavity (2) which at once reaches the high heat delivered from the compartment (5) upon opening of the separator (6).
The time the oven cavity (2) reaches the desired temperature for foods that do not have to cook at a certain temperature is shortened since the time the compartment (5), having a smaller volume than the oven cavity (2), reaches the desired temperature is short. Consequently, the total cooking time is shortened and energy consumption decreases.
In ovens (1) wherein the type and amount of foods are detected depending on their humidity and weight after being placed in the oven cavity (2) and a cooking algorithm is determined accordingly, the food has to be placed into the oven cavity (2) that is at room temperature. While the type and amount of foods placed into the oven cavity (2) are detected, the compartment (5) is heated by the heater (4) when the separator (6) is closed. After determining the cooking algorithm and when cooking is about to start, the separator (6) is opened, providing the heat of the compartment (5) to pass into the oven cavity (2). Consequently, both type and amount of the food is detected and also the heater (4) is operated for reaching the desired temperature at the same time and saving of time is provided.
In an embodiment of the present invention, the oven (1) comprises a movement mechanism (8) that provides the separator (6) to move between the open and closed positions (Figures 3, 4 and 5). The movement mechanism (8) provides the separator (6) to be closed when the oven (1) is to be started. The compartment (5) is heated by the heater (4) when the separator (6) is in the closed position. The movement mechanism (8) provides the separator (6) to be opened when the compartment (5) reaches the desired temperature. Air flow from the compartment (5) to the oven cavity (2) is realized while the separator (6) is open, providing the oven cavity (2) to be heated. The separator (6) remains open during the cooking.
In an embodiment of the present invention, the movement mechanism (8) comprises shape memory elements (not shown in the figures). The elements that change shape when actuated by a certain temperature and current, enable the movement mechanism (8) to activate the separator (6). For example, an element that elongates upon reaching a certain temperature provides the movement mechanism (8) to be activated.
The oven (1) furthermore comprises a control unit (7) that controls the temperature the compartment (5) reaches, providing the separator (6) to open when the temperature of the compartment (5) reaches a value recorded in its memory by the producer (Figure 1). The control unit (7) provides the separator (6) to remain closed until the compartment (5) temperature reaches a value that provides the oven cavity (2) temperature to reach the cooking temperature when the separator (6) is opened. For this, the control unit (7) has a locking mechanism (not shown in the figures) that provides the separator (6) to remain closed.
In an embodiment of the present invention, the control unit (7) provides the temperature of the compartment (5) to be above the cooking temperature by an amount predetermined by the producer and the user. The control unit (7) provides the heater (4) to operate and the separator (6) to remain closed until the temperature of the compartment (5) reaches the determined value. After the compartment (5) reaches the determined value, the separator (6) opens and the air of the compartment (5) disperses into the oven cavity (2). When the air heated in the compartment (5) mixes with the air in the oven cavity (2) that is at room temperature at the start, the temperature of the oven cavity (2) rises to a value in between the temperature reached by the compartment (5) and the room temperature. Since the compartment (5) reaches a temperature above the cooking temperature, by as much as the determined value, the oven cavity (2) reaches the desired cooking temperature after the separator (6) is opened.
In an embodiment of the present invention, the control unit (7) controls placement of food in the oven cavity (2) and closing of the door (3), allowing the separator (6) to open while there is food in the oven cavity (2) and while the door (3) is closed. The control unit (7) can detect whether or not food is present in the oven cavity (2) by, for example, a weight sensor (not shown in the figures) disposed on the base of the oven cavity (2) or by a humidity sensor (not shown in the figures) that detects the vapor rising from the food. The control unit (7) can detect whether or not the door (3) is open, by means of, for example, a switch (not shown in the figures) disposed on the oven (1), that changes position when the door (3) contacts thereto. Consequently, the control unit (7) prevents the heat of the compartment (5) from escaping outside by preventing the separator (6) from opening while the door (3) is open and thereby avoids energy consumption.
In another embodiment of the present invention, the oven (1) comprises an intermediate wall (9) disposed between the compartment (5) and the oven cavity (2) and more than one separator (6) disposed on the intermediate wall (9) (Figure 3 and Figure 4).
In another embodiment of the present invention, the separator (6) is produced from shape memory material that allows the hot air in the compartment (5) to pass into the oven cavity (2) by changing shape when heat or electricity is applied thereon. The separator (6) changing shape with heat, provides insulation between the compartment (5) and the oven cavity (2) at room temperature, changes shape when the compartment (5) reaches a certain temperature and allows the hot air in the compartment (5) to pass into the oven cavity (2). Thus, the separator (6) changes to the open position by itself when the desired temperature is attained without requiring the intervention of the user. The separator (6) that changes shape with electricity is in form of a plate which is provided to expand or contract by applying electricity when desired to be changed, for example, to the open or closed position. The separator (6) is provided to change shape by delivering electricity when the compartment (5) is detected to reach the determined temperature or by the intervention of the user. Thus, the separator (6) opens by itself without requiring to touch the heated separator (6).
In an embodiment of the present invention, the oven (1) comprises the heater (4) disposed in the compartment (5) and a fan (10) that provides circulation of the air heated by the heater (4) (Figure 4). When the fan (10) and the heater (4) are operated together, the compartment (5) is provided to be heated more quickly by the hot air circulated therein. The separator (6) is opened after the compartment (5) reaches the determined temperature, the fan (10) blows the accumulated hot air in the compartment (5) towards the oven cavity (2). Consequently, the oven cavity (2) reaches the desired temperature in a short period of time.
In another embodiment of the present invention, the oven (1) comprises two side walls (11) and the plate shaped separator (6), one side mounted on the side wall (11) so as to be rotated by the movement mechanism (8), changed to a position vertical to the side wall (11) by the movement mechanism (8) when the compartment (5) is desired to be separated from the oven cavity (2), and folded towards the side wall (11) by the movement mechanism (8) when the compartment (5) is desired to be opened to the oven cavity (2) (Figure 5). When in the horizontal position, the separator (6) extends between the side walls (11) and is in the closed position. When desired to be changed to the open position, the separator (6) is folded towards the side walls (11) and changed to almost vertical position. Thus, air communication is provided between the compartment (5) and the oven cavity (2). In ovens (1) comprising, for example, two separators (6), the separators (6) separate the compartment (5) from the oven cavity (2) by overlapping on one another when in the horizontal position.
In an embodiment of the present invention, the compartment (5) is situated inside the oven cavity (2). Thus, the heat of the compartment (5) is provided to reach the oven cavity (2) in a short period of time without heat loss when the separator (6) is changed to the open position.
In an embodiment of the present invention, the oven (1) comprises a button (12) that enables the separator (6) to be opened/closed by the user (Figure 1). Thus, the user can determine the temperature the oven cavity (2) reaches and/or the time when the separator (6) opens.
In the oven (1) of the present invention, when the oven cavity (2) is at room temperature, the compartment (5) is heated by means of the heater (4). When the separator (6) that separates the oven cavity (2) and the compartment (5) from each other is changed to the open position, the heat of the compartment (5) passes into the oven cavity (2). Thus, the food that is placed in the oven cavity (2) before the separator (6) is opened, starts cooking with the heat coming from the compartment (5) without opening the door (3) of the oven (1). Consequently, heat loss from the door (3) is prevented and energy saving is provided. Furthermore, the oven cavity (2) is provided to reach the desired temperature in a short period of time by means of the compartment (5) being heated in a short time and the total cooking time becomes shorter.
It is to be understood that the present invention is not limited to the embodiments disclosed above and a person skilled in the art can easily introduce different embodiments. These should be considered within the scope of the protection postulated by the claims of the present invention.

Claims

An oven (1) comprising an oven cavity (2) wherein trays containing foods to be cooked are placed, a door (3) allowing access into the oven cavity (2) and at least one heater (4), characterized by a compartment (5) having air flow between itself and the oven cavity (2) and at least one separator (6) that prevents air flow between the oven cavity (2) and the compartment (5) when closed, allowing passage of air from the compartment (5) into the oven cavity (2) when opened.
An oven (1) as in Claim 1, characterized by a movement mechanism (8) that provides the separator (6) to be moved between the open and closed positions.
An oven (1) as in Claim 2, characterized by the movement mechanism (8) that comprises shape memory elements.
An oven (1) as in any one of the above Claims, characterized by a control unit (7) that controls the temperature the compartment (5) reaches, providing the separator (6) to open when the temperature of the compartment (5) reaches a value recorded in its memory by the producer.
An oven (1) as in Claim 4 , characterized by the control unit (7) that provides the temperature of the compartment (5) to be above the cooking temperature by an amount predetermined by the producer and the user.
An oven (1) as in Claim 4 or 5, characterized by the control unit (7) that provides the separator (6) to open while there is food in the oven cavity (2) and the door (3) is closed.
An oven (1) as in any one of the above Claims, characterized by an intermediate wall (9) disposed between the compartment (5) and the oven cavity (2) and the separator (6) disposed on the intermediate wall (9).
An oven (1) as in any one of the above Claims, characterized by the separator (6) produced from shape memory material that allows the hot air in the compartment (5) to pass into the oven cavity (2) by changing shape when heat or electricity is applied thereon.
An oven (1) as in any one of the above Claims, characterized by the heater (4) disposed in the compartment (5) and a fan (10) that provides circulation of the air heated by the heater (4).
An oven (1) as in Claim 2 and/or 3, characterized by the plate shaped separator (6), comprising two side walls (11) and one side mounted on the side wall (11) so as to be rotated by the movement mechanism (8), changed to a position vertical to the side wall (11) by the movement mechanism (8) when the compartment (5) is desired to be separated from the oven cavity (2), and folded towards the side wall (11) by the movement mechanism (8) when the compartment (5) is desired to be opened to the oven cavity (2).
An oven (1) as in any one of the above Claims, characterized by the compartment (5) that is disposed inside the oven cavity (2).
An oven (1) as in any one of the above Claims, characterized by a button (12) that enables the separator (6) to be opened/closed by the user.