Patent Application
20200187314
The present disclosure generally relates to a cooking apparatus, and more particularly, to a microwave oven having multiple feeds for heating a cavity of the microwave oven.
The art of microwave heating involves the feeding of microwave energy into a cavity. Although the basic function of a microwave oven is to heat food by dielectric heating (i.e., via direct acting microwaves absorbed in the food), microwave ovens have been developed to include additional kinds of cooking capabilities, such as a crisp (or browning) function, thereby enabling preparation of various types of food items and providing new culinary effects.
A drawback of many current microwave ovens is that their design may be optimized for a specific function (typically the directly acting microwaves) at the detriment of another function (typically the crisp function). For instance, the crisp function in such microwave ovens is usually obtained via the same feeding system used for direct acting microwaves, and as a result, the performance of the crisp function may suffer.
According to one aspect, a microwave oven is provided and includes a cavity. A first microwave supply system is configured to supply microwaves to a bottom of the cavity for energizing a crisp function. A second microwave supply system is configured to supply microwaves to the cavity for exciting cavity modes. A heating system is configured to provide a broiling function to the cavity. A control unit is configured to control the first microwave supply system, the second microwave supply system, and the heating system based on a mode of operation selected via a user interface.
According to another aspect, a microwave oven is provided and includes a cavity having a bottom tray. A crisp plate is in thermal contact with the bottom tray. A first microwave supply system is provided and includes a first microwave generator for generating microwaves and a rotatable antenna for receiving the generated microwaves via a first feeding port and supplying the generated microwaves under the bottom tray for heating a sole of the crisp plate to a Curie point. A second microwave supply system is provided and includes a second feeding port provided at a first side wall of the cavity, a third feeding port provided at a second side wall of the cavity, wherein the second side wall is opposite to the first side wall, and at least one microwave generator for generating microwaves supplied to the cavity via the second and third feeding ports. A heating system is configured to provide a broiling function to the cavity. A control unit is configured to activate the first microwave generator, the at least one microwave generator, and the heating system to provide a crisp function to the cavity.
According to yet another aspect, a method of crisping a food item in a microwave oven is provided. The method includes the steps of providing a bottom tray in a cavity of the microwave oven; providing a crisp plate in thermal contact with the bottom tray; supplying microwaves to a bottom of a cavity for heating a sole of the crisp plate to a Curie point; supplying microwaves to the cavity for exciting cavity modes; and activating a heating system to provide a broiling function to the cavity.
These and other aspects, objects, and features of the present disclosure will be understood and appreciated by those skilled in the art upon studying the following specification, claims, and appended drawings.
In the drawings:
It is to be understood that the specific devices and processes illustrated in the attached drawings, and described in the following specification are simply exemplary embodiments of the inventive concepts defined in the appended claims. Hence, other physical characteristics relating to the embodiments disclosed herein are not to be considered as limiting, unless the claims expressly state otherwise.
As used herein, the term “and/or,” when used in a list of two or more items, means that any one of the listed items can be employed by itself, or any combination of two or more of the listed items can be employed. For example, if a composition is described as containing components A, B, and/or C, the composition can contain A alone; B alone; C alone; A and B in combination; A and C in combination; B and C in combination; or A, B, and C in combination.
With reference to
With continued reference to
Advantageously, the rotatable antenna 20 may be configured to produce a radiating lobe such that the ring-shaped heating pattern 28 covers about 10 to 50 percent of the bottom tray 18. In particular, the rotatable antenna 20 may be configured to produce a radiating lobe pointing in a direction forming an angle in the range of 0-90 degrees, and more preferably in the range of 30-60 degrees, with the bottom tray 18. Depending on the size of the rotatable antenna 20 relative to the size of the bottom tray 18 or depending on the location of the antenna opening through which microwaves are generated at the bottom of the cavity 14 relative to the position of the bottom tray 18, the radiating lobe may be directed perpendicular to the bottom tray 18 or included such that the radiating lobe points at the periphery of the bottom tray 18. As the electromagnetic field is concentrated at a specific point or hot spot 26 of the bottom tray 18, it is advantageous if the radiating lobe is not directed towards the center of the bottom tray 18 in order to avoid local overheating. Indeed, if the radiating lobe points too close to the center of the bottom tray 18, the coverage area of the heating pattern will be limited and the uniformity of a crisp function, for example, will be relatively poor. It is thus particularly advantageous if the radiating lobe is inclined and points at the periphery of the bottom tray 18 since a relatively large ring-shaped heating pattern 28 may then be created in the bottom tray 18 under rotation of the rotatable antenna 20.
In the depicted embodiment of
With reference to
Depending on the design of the rotatable antenna 20 and its boundary conditions (e.g., the disposition of the bottom 24 of the cavity 14), the opening 32 may result in one or several radiating lobes propagating in a general horizontal and/or inclined direction (e.g., horizontal direction 42, inclined direction 44) relative to the bottom 24 of the cavity 14. Accordingly, the a portion of the microwaves supplied by the rotatable antenna 20 may be provided to energize a crisp function while the remaining portion of the microwaves may be provided to excite cavity modes at the bottom 24 of the cavity. While the rotatable antenna 20 has been shown and described herein as having a single opening 32, it is to be understood that the rotatable antenna 20 may be configured with multiple openings. For example, additional openings may be formed through the sector-shaped panel 30. In so doing, additional hot spots and accompanying ring-shaped heating patterns may be created at other locations of the bottom tray 18 to improve the uniformity of the crisp function.
With continued reference to
The first member 48 may be a ceramic such as rubber-embedded ferrite (e.g., in a proportion of about 75% ferrite and 25% silicon dioxide). The ferrite material has a Curie point at which absorption of the microwaves therein ceases. The characteristics for absorption of the microwaves in the ferrite material may be varied by altering the thickness of the first member 48 and/or the composition thereof. Generally the temperature of the second member 50 of the crisp plate 46 that comes into contact with the food item stabilizes in a temperature range of 130-230 degrees Celsius. While the crisp plate 46 is illustrated in
With further reference to
In the presently depicted embodiment, the first, second, and/or third microwave generators 22, 56, 64 are solid-state based microwave generators, which advantageously enable controlling of the frequency and phase of the generated microwaves, controlling the output power of the microwave generator, and an inherent narrow-band spectrum. The frequencies of the microwaves that are emitted from a solid-state based microwave generator usually include a narrow range of frequencies such as 2.4 to 2.5 GHz. However, it is to be understood that other frequency ranges are possible as well.
The microwave oven 10 further includes a heating system 72 having a heating element 74 arranged at a ceiling 76 of the cavity 14 for providing an additional source of heating to the cavity 14, thereby increasing the cooking capability of the microwave oven 10. The heating element 74 may be configured to provide a broiling function to the cavity 14 based on direct heat or forced convection, and may include, for example, a grill tube, a quartz tube, a halogen-radiation source, or an infrared-radiating heater.
As further shown in
According to the depicted embodiment of
Referring to Table 1 below, several modes of operation are shown for the purposes of illustration. Each mode of operation may be selected via the user interface 86 and is implemented by the control unit 78. As will be described below, the inclusion of the first microwave supply system 52, the second microwave supply system 54, and the heating system 72 impart greater versatility to the microwave oven 10, thereby enabling a user to achieve a variety of culinary effects. As shown, the microwave oven 10 includes a crisp mode that will be described in greater detail with reference to
With reference to
With reference back to Table 1, other modes of operation may also be achieved by leveraging one or more of the first microwave supply system 52, the second microwave supply system 54, and the heating system 72. For instance, a defrost mode may be selected via the user interface 86, which prompts the control unit 78 to only activate the second microwave supply system 54 such that the second and third microwave generators 56, 64 generate microwaves supplied to the cavity 14. In contrast, when an even heating mode is selected via the user interface 86, the control unit 78 only activates both the first and second microwave supply systems 52, 54 such that the first, second, and third microwave generators 22, 56, 64 generate microwaves supplied to the cavity 14. In contrast still, when a controlled heating mode is selected via the user interface 86, the control unit 78 only activates the second microwave supply system 54 and the heating system 72 such that the second and third microwave generators 56, 64 generate microwaves supplied to the cavity 14 and the heating element 74 provides a broiling function to the cavity 14. In further contrast, when a bottom heating mode is selected via the user interface 86, the control unit 78 only activates the first microwave supply system 52 such that the first microwave generator 22 generates microwaves supplied to the cavity 14.
For purposes of this disclosure, the term “coupled” (in all of its forms, couple, coupling, coupled, etc.) generally means the joining of two components (electrical or mechanical) directly or indirectly to one another. Such joining may be stationary in nature or movable in nature. Such joining may be achieved with the two components (electrical or mechanical) and any additional intermediate members being integrally formed as a single unitary body with one another or with the two components. Such joining may be permanent in nature or may be removable or releasable in nature unless otherwise stated.
It is also important to note that the construction and arrangement of the elements of the device as shown in the exemplary embodiments is illustrative only. Although only a few embodiments of the present innovations have been described in detail in this disclosure, those skilled in the art who review this disclosure will readily appreciate that many modifications are possible (e.g., variations in sizes, dimensions, structures, shapes and proportions of the various elements, values of parameters, mounting arrangements, use of materials, colors, orientations, etc.) without materially departing from the novel teachings and advantages of the subject matter recited. For example, elements shown as integrally formed may be constructed of multiple parts or elements shown as multiple parts may be integrally formed, the operation of the interfaces may be reversed or otherwise varied, the length or width of the structures and/or members or connector or other elements of the system may be varied, the nature or number of adjustment positions provided between the elements may be varied. It should be noted that the elements and/or assemblies of the system may be constructed from any of a wide variety of materials that provide sufficient strength or durability, in any of a wide variety of colors, textures, and combinations. Accordingly, all such modifications are intended to be included within the scope of the present innovations. Other substitutions, modifications, changes, and omissions may be made in the design, operating conditions, and arrangement of the desired and other exemplary embodiments without departing from the spirit of the present innovations.
It will be understood that any described processes or steps within described processes may be combined with other disclosed processes or steps to form structures within the scope of the present disclosure. The exemplary structures and processes disclosed herein are for illustrative purposes and are not to be construed as limiting.
It is also to be understood that variations and modifications can be made on the aforementioned microwave oven 10 without departing from the concepts provided herein, and further it is to be understood that such concepts are intended to be covered by the following claims unless these claims by their language expressly state otherwise.
The above description is considered that of the illustrated embodiments only. Modifications of the device will occur to those skilled in the art and to those who make or use the device. Therefore, it is understood that the embodiments shown in the drawings and described above is merely for illustrative purposes and not intended to limit the scope of the device, which is defined by the following claims as interpreted according to the principles of patent law, including the Doctrine of Equivalents.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US2016/039835 | 6/28/2016 | WO | 00 |
