US20090064986A1

US20090064986A1 - Cooking oven, especially household finishing oven

Info

Publication number: US20090064986A1
Application number: US12/298,943
Authority: US
Inventors: Karl Leidig; Reiner Horstmann
Original assignee: Electrolux Home Products Corp NV
Current assignee: Electrolux Home Products Corp NV
Priority date: 2006-05-05
Filing date: 2007-05-02
Publication date: 2009-03-12
Also published as: EP2016340A1; CA2651191A1; AU2007247452B2; AU2007247452A1; WO2007128471A1; DE102006020914A1

Abstract

The invention relates to an oven (1), in particular a home cooking oven featuring a cooking chamber (2) in which food to be cooked is placed and which can be closed with an oven door (3), with means provided that allow a stream of hot air and/or steam to be passed through the cooking chamber (2). To achieve better heating of the food to be cooked, the invention provides for the means serving to pass a stream of hot air and/or steam through the cooking chamber (2) to incorporate a fan (4) on the far side of the cooking chamber (2) away from the oven door (3), as well as a flow conduit (5) that extends above the cooking chamber (2) and leads from the fan (4) into the area of the oven door (3), said flow conduit (5) featuring an outlet port (6) that is situated above the oven door (3) and directs heated air or steam downward into the cooking chamber (2).

Description

The invention relates to an oven, in particular a home cooking oven featuring a cooking chamber in which food to be cooked is placed and which can be closed with an oven door, with means provided that allow a stream of hot air and/or steam to be passed through the cooking chamber.
Home kitchen ovens along this concept have been well known in prior art. In a conventional oven, electric heating elements are positioned in the bottom- and top-panel area, serving to heat up the food being cooked.
Also known are convection ovens in which heat in the form of hot air is directed at the food being cooked. In many cases this is accomplished merely by positioning a fan in the cooking chamber, serving to move the air in the cooking chamber.
With these earlier designs it is possible to adequately heat the food being cooked within a certain length of time. On occasions it is desirable to reduce the cooking time, which requires special measures.
A known approach to that end is to generate hot air or steam which is fed into the cooking chamber. In most cases it is desirable to produce a turbulent flow in that the hot-air or steam feeder elements generate a corresponding eddy effect.
It is the objective of this present invention to advance the above-mentioned cooking-oven design in a manner whereby the cooking time can be reduced while the object food is still to be heated as gently as possible.
To achieve this objective, the invention is characterized in that the means serving to pass a stream of hot air and/or steam through the cooking chamber include a fan situated on the far side of the cooking chamber away from the oven door and that said means additionally include a flow conduit that extends above the cooking chamber, leading from the fan into the area of the oven door, said flow conduit featuring an outlet port that is located above the oven door and directs heated air and/or steam downward into the cooking chamber.
Specifically and preferably, the fan, the flow conduit and the outlet port are so designed as to produce a laminar flow of the heated air and/or steam through the cooking chamber. This will heat the food being cooked not only in quick but also in gentle fashion.
The inside of the flow conduit is preferably equipped with heating elements for heating the air and/or steam as it passes through. These heating elements will usually be in the form of electric heating elements.
At least over certain segments the flow conduit preferably has a rectangular cross section. The fan is advantageously positioned in a housing that constitutes at least part of the wall of the cooking chamber. In that case it is also possible to provide the housing with an air and/or steam inlet opening on the side facing the cooking chamber.
The heating of the food being cooked is further improved by additionally providing a planar, usually electric heating element in the bottom area of the cooking chamber. It is possible to interposition between that heating element and the cooking chamber a plate, preferably in the form of a glass-ceramic plate that is heat-transparent and especially heat-conducting and/or pervious to radiated heat.
The axis of rotation of the fan can extend in the longitudinal direction of the cooking chamber from the oven door toward the rear wall of the cooking chamber. The fan may be driven by a motor that is laterally offset from the axis of rotation of the fan. In that case the transfer of the torque between the motor and the fan can be accomplished via a belt.
The approach proposed by this invention makes it possible to achieve rapid and gentle heating of the food being cooked.
A stream of air and/or steam can be passed through the cooking chamber at a rate of up to about 400 m³/h while maintaining a laminar flow. As a result, the food being cooked is heated very gently. The added introduction of heat by way of the bottom plate advantageously supplies the cooking chamber with sufficient thermal energy.
The invention thus employs a combination of hot air and/or steam and radiated heat. This results in the efficacious heating of the food being cooked within a short time.

A design example of the invention is illustrated in the attached drawings in which:

FIG. 1 is a perspective view of the main body of a home cooking oven;

FIG. 2 is a rear view of the main body of the oven; and

FIG. 3 is a side-view cross section of the main body of the oven.

The figures show an oven 1, i.e. the main body of an oven without the surrounding enclosure. The oven 1 includes a cooking chamber 2 the front of which can be closed with a hinged oven door 3. The food being cooked in the cooking chamber 2 is heated as follows:
The oven 1 is equipped with means 4, 5, 6, 7 serving to pass a stream of hot air and/or steam through the cooking chamber 2. The means begin with a fan 4 that is positioned in a housing 8. The housing 8 is located in the rear of the cooking chamber 2 facing away from the oven door 3. The fan 4 is driven by a motor 14. The axis of rotation 13 of the fan and that of the motor 14 are mutually parallel. The motor 14 transmits the torque to the fan 4 by means of a belt 15.
Driving the fan 4 causes air and/or steam to be fed into an upper region 16 of the housing 8 and from there, through a flow conduit 5, toward the front in the direction of the oven door 3. As is most clearly seen in FIG. 3, the air and/or steam exits from the flow conduit 5 through an outlet port 6 from where, in the area of the oven door 3, it flows downward into the cooking chamber 2. The arrows in FIG. 3 indicate the flow of the air or steam.
The housing 8 is provided with an inlet opening 9 through which air and/or steam can be drawn back out of the cooking chamber, resulting in a closed-loop circulation or flow pattern. The air or steam is heated by a heating element 7 that is positioned in the flow conduit 5.
Additional heat is introduced in the cooking chamber 2 through thermal radiation or heat conduction. This is accomplished by means of a heating element 11 positioned in the bottom area 10 of the cooking chamber 2, underneath a glass-ceramic plate 12. This type of heating is also known as DHC (direct heat conduction) heating, meaning that it employs direct electric heating.
This design configuration permits both rapid and gentle heating of the food being cooked. The housing 8 is wide (see FIG. 2), feeding through an equally wide flow conduit 5 a laminar stream of air and/or steam across the cooking chamber 2. For the same reason, the outlet port 6 is in the form of a long slit that may extend over most of the width of the cooking chamber 2. Preferably, the width of the flow conduit 5 and that of the outlet port 6 is at least 70% of the width of the oven 1.

LIST OF REFERENCE NUMBERS

1 oven
2 cooking chamber
3 oven door
4, 5, 6, 7 means for conducting a stream of hot air and/or steam
4 fan
5 flow conduit
6 outlet port
7 heating element
8 housing
9 inlet opening
10 bottom area
11 heating element
12 heat-permeable plate (glass-ceramic plate)
13 axis of rotation
14 motor
15 belt
16 upper region of the housing

Claims

1. Cooking oven (1), especially a home cooking oven, featuring a cooking chamber (2) in which food to be cooked can be placed and which can be closed with an oven door (3), with means provided that allow a stream of hot air and/or steam to be passed through the cooking chamber (2), characterized in that the means serving to pass a stream of hot air and/or steam through the cooking chamber (2) incorporate a fan (4) on the far side of the cooking chamber (2) away from the oven door (3), as well as a flow conduit (5) that extends above the cooking chamber (2) and leads from the fan (4) into the area of the oven door (3), said flow conduit (5) featuring an outlet port (6) that is situated above the oven door (3) and directs heated air and/or steam downward into the cooking chamber (2).

2. Cooking oven as in claim 1, characterized in that the fan (4), the flow conduit (5) and the outlet port (6) are so designed as to produce a laminar flow of the heated air and/or steam through the cooking chamber (2).

3. Cooking oven as in claim 1, characterized in that heating elements (7) are provided inside the flow conduit (5) to heat the air and/or steam as it passes by them.

4. Cooking oven as in claim 3, characterized in that the heating elements (7) are electric heating elements.

5. Cooking oven as in one of the claim 4, characterized in that at least over certain segments the flow conduit (5) has a rectangular cross section.

6. Cooking oven as in claim 5, characterized in that the fan (4) is positioned in a housing (8) that constitutes at least part of the wall of the cooking chamber (2).

7. Cooking chamber as in claim 6, characterized in that the housing (8) is provided with an opening (9) to allow the passage of air and/or steam on the side facing the cooking chamber (2).

8. Cooking oven as in claim 1, characterized in that a planar heating element (11) is provided in the bottom area (10) of the cooking chamber (2).

9. Cooking oven as in claim 8, characterized in that the heating element is an electric heating element.

10. Cooking oven as in claim 8, characterized in that a heat-permeable plate (12) is positioned between the heating element (11) and the cooking chamber (2).

11. Cooking oven as in claim 10, characterized in that the heat-permeable plate (12) is a glass-ceramic plate.

12. Cooking oven as in claim 1, characterized in that an axis of rotation (13) of the fan (4) extends in the longitudinal direction of the cooking chamber (2) from the oven door (3) toward the rear wall of the cooking chamber (2).

13. Cooking oven as in claim 12, characterized in that the fan (4) is driven by a motor (14) that is laterally offset from the axis of rotation (13) of the fan (4).

14. Cooking oven as in claim 13, characterized in that the rotational connection between the motor (14) and the fan (4) is provided via a belt (15).