US20140026880A1

US20140026880A1 - Air flow management for an oven appliance with hidden heating source

Info

Publication number: US20140026880A1
Application number: US13/556,580
Authority: US
Inventors: Stephen Bernard Froelicher; Joshua Stephen Wiseman
Original assignee: General Electric Co
Current assignee: Haier US Appliance Solutions Inc
Priority date: 2012-07-24
Filing date: 2012-07-24
Publication date: 2014-01-30

Abstract

An oven appliance with one or more features for managing the flow of heated air within the oven cavity is provided. Such features are provided on a floor or wall that is positioned over one or more heating elements. The features are configured to disrupt the formation and/or flow of a high temperature film so that heated air is more uniformly distributed within the oven cavity in order to promote a more uniform cooking of food items therein.

Description

FIELD OF THE INVENTION

The subject matter of the present disclosure relates generally to air flow management in the cooking cavity of an oven appliance.

BACKGROUND OF THE INVENTION

An oven appliance typically includes an oven cavity where food items can be placed onto one or more racks for cooking One or more heating sources are provided to provide heat energy into the oven cavity. These heating sources may include e.g., electrically resistant elements, gas burners, and others. The food may receive radiant energy as well as heat energy through conduction and/or convection inside the oven cavity.
For reasons that include aesthetics and protection of the heating element, modern designs commonly hide or cover heating sources that are located at or below a floor of the cavity. By way of example, referring to the cross-sectional front view of an oven cooking cavity shown in FIG. 1, one or more heating elements 50 may be contained within a compartment 52 located beneath the cavity floor or bottom wall 54 of the oven cavity 56. As such, upon activation of the heating elements 50, the cavity floor 54 is heated. This heat is then conducted to air in the oven cavity 56.
When the oven is operating in non-convective mode, as the temperature of the air near the cavity floor 54 is increased relative to other air in cavity 56, it becomes buoyant and begins to move upwardly along vertical direction V. Instead of travelling upward to the underside of rack 64 to heat food items 62, some of this buoyant air will travel as a high temperature boundary layer or film 58 in the direction of arrows F along cavity floor 54 and then along cavity side walls 60. Upon reaching the top of cavity 66, this high temperature air will be turned back towards food items 62 on rack 64 and will pool over items 62 as indicated in FIG. 1 by arrows P.
As a result of the above-described effect, the food items 62 are prone to top browning due to the pooling of high temperature air above items 62. This can be undesirable for several reasons. For example, the aesthetics of the foods items 62 may be non-uniform, the top of the food may be cooked or overdone, while the bottom may be undercooked or raw, and other reasons as well.
Accordingly, an oven appliance that can provide a more uniform cooking of food items is desirable. More particularly, an oven appliance that has features for managing the direction of air flow in the oven so as to promote a more even cooking of food items in the oven cavity would be useful. Such features would be particularly beneficial in an oven appliance that has one or more heating element hidden or covered below a floor or bottom wall of the oven cavity.

BRIEF DESCRIPTION OF THE INVENTION

The present invention provides an oven appliance with one or more features for managing the flow of heated air within the oven cavity. Such features are provided on a floor or wall that is positioned over one or more heating elements. The features are configured to disrupt the formation and/or flow of a high temperature film so that heated air is more uniformly distributed within the oven cavity in order to promote a more uniform cooking of food items therein. Additional aspects and advantages of the invention will be set forth in part in the following description, or may be apparent from the description, or may be learned through practice of the invention.
In one exemplary embodiment, the present invention provides an oven appliance that includes an oven cavity for the receipt of food items for cooking A bottom wall defines at least a lower part of the oven cavity. The bottom wall includes at least one connecting portion and at least one air directing portion. The air directing portion includes a surface for directing a flow of heated air upwardly in the oven cavity. A heating source is located below the bottom wall for providing heat energy to the oven cavity.
In another exemplary embodiment, the present invention provides an oven appliance that includes an oven cavity for the receipt of foods for cooking The oven cavity is defined in part by a cavity floor and a top wall. The cavity floor includes a plurality of air directing portions, each air directing portion including at least one surface projecting upwardly into the oven cavity so as to direct a flow of heated air upwardly into the oven cavity. A heat source is positioned below the cavity floor for providing heat energy to the oven cavity.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:

FIG. 1 provides a cross-sectional view of a conventional oven cavity with a schematic depiction of air movement therein.

FIG. 2 illustrates a front view of an exemplary embodiment of an oven of the present invention.

FIG. 3 is a cross-sectional view of an exemplary oven cavity of the present invention with a schematic depiction of air movement therein.

FIG. 4 is a close-up of a portion of the floor or bottom wall of the exemplary oven cavity of FIG. 3.

FIGS. 5-7 illustrate alternative exemplary embodiments of oven cavities of the present invention where only a lower portion of the oven cavity is shown.

The same or similar reference numerals appearing the figures may be used to represent the same or similar features.

DETAILED DESCRIPTION OF THE INVENTION

Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Referring to FIGS. 2 and 3, an exemplary embodiment of an oven 100 according to the present invention is shown. FIG. 1 provides a front view of oven 100 while FIG. 2 provides a front, cross-sectional view of the cooking chamber or oven cavity 156. Oven 100 includes a door 104 with handle 106 that provides for opening and closing access to oven cavity 156. A user of the appliance 100 can place a variety of different items 162 to be cooked on one or more racks 164 in oven cavity 156. A window 110 on door 104 allows the user to view e.g., food items during the cooking process. Insulation and/or ventilation passage ways may be located in the space 168 located between cabinet 170 and walls 160 and 166.
Oven cavity 156 is defined in part by a top wall 166, a pair of opposing side walls 160, and bottom wall 154. One or more heating sources 150 are located in a compartment 152 positioned below bottom wall 154. Heating sources 150 may be electrical resistant elements, gas burners, or other heat sources. Additional heating sources may be located at or behind top wall 166 as well. Upon activation, heating sources 150 provide heat that is transferred to bottom wall 154 and conducted to air in oven cavity 156.
Oven 100 includes a user interface 102 having a display 103 positioned on a top panel 114 with a variety of controls 112. Interface 102 allows the user to select various options for the operation of oven 100 including e.g., temperature, time, and/or various cooking and cleaning cycles. Operation of oven appliance 100 can be regulated by a controller (not shown) that is operatively coupled i.e., in communication with, user interface panel 102, heating element 150, and other components of oven 100 as will be further described.
For example, in response to user manipulation of the user interface panel 102, the controller can operate heating element 150. The controller can receive measurements from a temperature sensor (not shown) placed in cooking chamber 156 and e.g., provide a temperature indication to the user with display 103. The controller can also be provided with other features as will be further described herein.
By way of example, the controller may include a memory and one or more processing devices such as microprocessors, CPUs or the like, such as general or special purpose microprocessors operable to execute programming instructions or micro-control code associated with operation of appliance 100. The memory may represent random access memory such as DRAM, or read only memory such as ROM or FLASH. In one embodiment, the processor executes programming instructions stored in memory. The memory may be a separate component from the processor or may be included onboard within the processor.
The controller may be positioned in a variety of locations throughout appliance 100. In the illustrated embodiment, the controller may be located under or next to the user interface 102 otherwise within top panel 114. In such an embodiment, input/output (“I/O”) signals are routed between the controller and various operational components of appliance 100 such heating sources 150, controls 112, display 103, sensor(s), alarms, and/or other components as may be provided. In one embodiment, the user interface panel 102 may represent a general purpose I/O (“GPIO”) device or functional block.
Although shown with touch type controls 112, it should be understood that controls 112 and the configuration of appliance 100 shown in FIG. 1 is provided by way of example only. More specifically, user interface 102 may include various input components, such as one or more of a variety of electrical, mechanical or electro-mechanical input devices including rotary dials, push buttons, and touch pads. The user interface 102 may include other display components, such as a digital or analog display device designed to provide operational feedback to a user. The user interface 102 may be in communication with the controller via one or more signal lines or shared communication busses. Also, oven 100 is shown as a wall oven but the present invention could also be used with other appliances such as e.g., a stand-alone oven, an oven with a stove-top, and other configurations as well.
Referring now to FIGS. 3 and 4, once heating sources 150 are activated, heat is transferred to the bottom wall 154 of the oven cavity 156 and then conducted to air in cavity 156. As the temperature increases, a film or boundary layer 158 of high temperature air is created near the surface 170 (FIG. 4) of bottom wall 154. Because the air in film 158 is at a higher temperature than other air in oven cavity 156, it becomes buoyant and will seek to rise along vertical direction V while travelling close to surface 170 as indicated by arrows F.
Bottom wall 154 includes a plurality of air directing portions 172, which in FIGS. 3 and 4 are illustrated as a plurality of dimples 174. For example, bottom wall 154 can be constructed from a metal sheet into which depressions can be formed to create dimples 174. Other shapes for air directing portions 172 may be used as well. Air directing portions 172 are spaced apart from each other and located between a plurality of connecting portions 176.
For the exemplary embodiment shown, connecting portions 176 of bottom wall 154 are relatively flat or planar while air directing portions 172 project into oven cavity 156 or extend upwardly along vertical direction V into oven cavity 156. However, other shapes such as e.g., arcuate or curved may be used for connecting portions 176. Each air directing portion 172 includes surfaces 178 and 180 for directing the flow of air in film 158 upwardly into oven cavity 156 as shown by arrows F. Surfaces 178 and 180 can have a variety of shapes including the convex shape shown as well as concave, arcuate, and others.
Due to the shape of surfaces 178, as air in film 158 travels over surface 178 under the effect of buoyancy created by heating with source 150, the air will move upwardly along vertical direction V upon reaching or nearing the center 182 of air directing portions 172. Air in film 158 travelling on the opposing surface 180 will behave similarly.
As a result, high temperature air from film 158 will travel upwardly from air directing portions 172 towards the bottom 184 of food items 162 and rack 164 as indicated by arrows B (FIG. 3). A portion of the surrounding air will also be entrained and directed upwardly as indicated by arrows E. This upwardly moving air will help cook food items 162 and, more particularly, provide heat energy directed at cooking the bottom (the side closest to rack 164) of food items 162. As this air cools, due to buoyancy differences it will fall or travel towards bottom wall 154 as indicated by arrows D (FIG. 3). A portion of high temperature air will still travel towards top wall 166 and be directed downwardly as indicated by arrows P (FIG. 3). This air will also help cook food items 162 and, more particularly, provide heat energy directed at cooking the top of food items 162. As such, air directing portions 172 work to more uniformly cook food items 162.
A variety of shapes, patterns, and other configurations can be used for air directing portions 172 and connecting portions 176. For example, FIG. 5 illustrates a cross-sectional view of a portion of an oven cavity 156 in which bottom wall 154 includes a plurality of exemplary air directing portions 172 shaped as dimples 174 spaced between connecting portions 176. A regular pattern of dimples 174 is shown. FIG. 6 illustrates another cross-sectional view of a portion of an oven cavity 156 in which bottom wall 154 also includes a plurality of exemplary air directing portions 172 shaped as dimples 174 spaced between connecting portions 176. In FIG. 6, a more irregular pattern of dimples 174 is shown.
FIG. 7 illustrates a cross-sectional view of a portion of an oven cavity 156 in which bottom wall 154 includes a plurality of exemplary air directing portions 172 shaped as ribs 186 spaced between connecting portions 176. For this exemplary embodiment, ribs 186 extend longitudinally from the front 188 to the back 190 of oven cavity 156. However, other orientations may also be used. For example, ribs 186 could extend longitudinally between opposing side walls 160. Different shapes for ribs 186 may be used as well.
It should also be understood that while multiple air directing portions 172 are shown, bottom wall 154 of oven cavity 156 could also be equipped with a single portion 172. By way of example, a single dimple 174 of much larger size could also be centrally positioned on bottom wall 154. Additionally, to help manage the movement of high temperature air in film 158, the slope of bottom wall 154 may also be modified. Returning to FIG. 4, bottom wall 154 is positioned at an angle θ from the horizontal or lateral direction L. For example, angle θ could be in the range of about 0 to about 5 degrees. Referring to FIG. 3, bottom wall 154 could be provided with a downward slope on each side of centerline C/L such that wall 154 slopes downwardly from centerline C/L towards opposing side walls 160. Due to buoyancy effects, this slope on each side of bottom wall 154 would further facilitate the separation of film 158 from bottom wall 154. Accordingly, connecting portions 176 do not have to be horizontally oriented and, instead, can also be at various angles θ from the horizontal or lateral direction. In addition, not all of the connecting portions 176 may lie in the same plane.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal languages of the claims.

Claims

What is claimed is:

1. An oven appliance, comprising:

an oven cavity for the receipt of food items for cooking;

a bottom wall defining at least a lower part of said oven cavity, said bottom wall comprising

at least one connecting portion,

at least one air directing portion, said air directing portion including a surface for directing a flow of heated air upwardly in said oven cavity; and

a heating source located below said bottom wall for providing heat energy to said oven cavity.

2. An oven appliance as in claim 1, further comprising:

a compartment positioned below said bottom wall;

wherein said heating source is positioned within said compartment.

3. An oven appliance as in claim 1, wherein said at least one air directing portion comprises a dimple projecting into said oven cavity.

4. An oven appliance as in claim 1, wherein said at least one air directing portion comprises a plurality dimples spaced about said bottom wall between a plurality of connecting portions, said dimples projecting into said oven cavity.

5. An oven appliance as in claim 1, wherein said at least one air directing portion comprises a rib projecting into said oven cavity.

6. An oven appliance as in claim 5, wherein said rib extends longitudinally from the front to the rear of said oven cavity.

7. An oven appliance as in claim 1, wherein said at least one air directing portion comprises a plurality of ribs spaced about said bottom wall between a plurality of connecting portions, said ribs projecting into said oven cavity.

8. An oven appliance as in claim 1, wherein said oven cavity defines a lateral direction and has a centerline, and wherein said bottom wall slopes downwardly along the lateral direction on each side of the centerline of said oven cavity.

9. An oven appliance as in claim 1, wherein the surface of said at least one air directing portion is convex.

10. An oven appliance as in claim 1, wherein the surface of said at least one air directing portion is concave.

11. An oven appliance, comprising:

an oven cavity for the receipt of foods for cooking, said oven cavity defined in part by a cavity floor and a top wall, said cavity floor comprising

a plurality of air directing portions, each air directing portion including at least one surface projecting upwardly into said oven cavity so as to direct a flow of heated air upwardly into said oven cavity;

a heat source positioned below the said cavity floor for providing heat energy to said oven cavity.

12. An oven appliance as in claim 11, wherein said plurality of air directing portions comprise a plurality of dimples spaced about said cavity floor.

13. An oven appliance as in claim 11, wherein said plurality of air directing portions comprise a plurality of ribs spaced about said cavity floor.

14. An oven appliance as in claim 13, wherein said plurality of ribs extend longitudinally between a front and a back of said cavity floor.

15. An oven appliance as in claim 13, wherein said oven cavity is further defined by a pair of opposing side walls, and wherein said plurality of ribs extend longitudinally between the pair of opposing side walls.

16. An oven appliance as in claim 11, further comprising a compartment positioned beneath said cavity floor, wherein said heat source is positioned in said compartment.

17. An oven appliance as in claim 11, wherein the at least one surface of each of said air directing portions is convex.

18. An oven appliance as in claim 11, wherein the at least one surface of each of said air directing portions is concave.

19. An oven appliance as in claim 11, further comprising a plurality of connecting portions extending between said air directing portions.

20. An oven appliance as in claim 19, wherein said connecting portions are planar.