Microwave oven with radiant energy heating element

Abstract

A heating device for a cooking appliance, such as a toaster or oven. The heating element may be exposed in a cavity of the appliance and may have a shield that allows infrared energy to pass through but blocks microwaves and / or provides physical support for internal components, such as quartz tubes or resistive elements. The shield may be grounded to one or more cavity walls through a grounding element engaged with the shield and a portion of the cavity walls. The heating element may emit a greater amount of infrared radiation in one direction than in the opposite direction, for example due to the convex shape or other shape of the resistive element. The plurality of sets of heating elements may be controlled such that the second element begins to emit visible light while the first element stops emitting visible light. The convective air may be directed to one or more heating elements that diffuse the air flow or otherwise prevent the air from directly flowing towards the food in the cavity.

Description

Background Art

[0001] Various appliances can be used to cook or otherwise heat food. For example, ovens are typically used to cook food for a long time at relatively low to moderate temperatures. On the other hand, microwave ovens utilize microwave energy and can heat at least some food more quickly. In some cases, microwave ovens also include one or more radiant heating elements. Summary of the invention

[0002] In some embodiments, a resistive heating element is provided that is configured for use in a microwave oven, for example, in which the heating element is located in a cooking cavity and is exposed to microwaves around its outer surface. In some cases, the heating element can be configured to help prevent microwaves from leaving the cooking cavity, for example, via a conductive element of the heating element that emits infrared radiation. In some examples, the heating element includes a tube having a wall defining an interior space, an outer surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall can be configured to allow infrared radiation to pass through the wall from the interior space to the outer surface, for example, the tube can be made of quartz or other materials that are relatively transparent to infrared radiation. The resistive element can extend in the interior space between the first end and the second end of the tube wall, and can include a circuit configured to emit infrared radiation in response to a current in the resistive element. As an example, the circuit can include a metal or other conductive component that heats up in response to the current in the circuit to emit infrared energy. A shield can extend over the outer surface of the tube, wherein the shield is configured to allow infrared radiation to pass through at least a portion of the shield and prevent microwaves used in the microwave oven from being incident on the tube. In some cases, the portion of the shield configured to allow infrared radiation to pass therethrough is configured to allow 70% to 90% of the infrared radiation emitted by the circuit to pass through the shield. The shield can help prevent microwaves in the cooking cavity from leaving the cavity via the resistive element by preventing microwaves from being incident on the tube.

[0003] In some examples, the shield has a tubular shape, for example, the shield can completely surround the tube. In some embodiments, the shield has a first portion extending along the length of the tube and configured to block the infrared radiation emitted by the circuit from passing through and a second portion extending along at least a portion of the length of the tube and configured to allow the infrared radiation emitted by the circuit to pass through the shield. As an example, the first portion of the shield may include a tubular wall section without an opening, and the second portion may include a conductive component with a plurality of openings, the opening being configured to allow infrared radiation to pass through the opening and block microwaves from passing through the opening. In some cases, the second portion may include a metal mesh or other conductive component with an opening that allows infrared energy to pass through but prevents microwaves from passing through the shield. In some cases, the circuit is configured to emit a greater amount of infrared radiation in a first direction than in a second direction opposite to the first direction, and the circuit may be configured so that the first direction extends through the second portion of the shield. Therefore, the heating element may be configured to emit a greater amount of infrared radiation in the direction in which the shield allows infrared energy to pass through. In some examples, the circuit defines a convex shape, such as a V-shape, extending between the first end and the second end and facing the first direction.

[0004] In some cases, the shield is configured to protect the tube from physical impact.The shield can be configured to be electrically grounded to a cavity wall of a microwave oven, for example, to help prevent microwaves from leaving the cooking cavity.

[0005] In some embodiments, the resistive heating element may include a tube having a wall defining an interior space, an outer surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall may be configured to allow infrared radiation to pass through the wall from the interior space to the outer surface, for example, the wall may be made of a quartz material. The resistive element may extend in the interior space between the first end and the second end and include a circuit configured to emit infrared radiation in response to a current in the resistive element. In some cases, the circuit may define a convex shape extending between the first end and the second end. In some examples, the convex shape may extend a distance of at least 20% of the length of the wall between the first end and the second end. In some cases, the circuit has a certain width in a direction perpendicular to the longitudinal axis, and the convex shape may extend a distance greater than the width. For example, the convex shape may have a width of at least 90% of the width of the circuit in a direction perpendicular to the longitudinal axis. In some embodiments, the convex shape faces a first direction, and the circuit is configured to emit a greater amount of infrared radiation in the first direction than in a second direction opposite to the first direction. In some examples, the circuit defines a concave shape extending between the first end and the second end and opposite the convex shape. For example, the convex shape can face in a first direction, and the concave shape can face in a second direction opposite to the first direction. The circuit can be configured to emit a greater amount of infrared radiation in the first direction than in the second direction. In some cases, the circuit is configured to emit 20% to 30% more infrared radiation in the first direction than in the second direction.

[0006] In some examples, the portion of the circuit defined as a convex shape includes a first planar portion arranged at a certain angle relative to the second planar portion. For example, the portion of the circuit can have a joint between the first portion and the second portion. In some cases, the portion of the circuit defined as a convex shape includes a first side portion and a second side portion opposite to each other, each of the first side portion and the second side portion having a serpentine shape defined by a bend connected by a leg, and the legs each extend between the corresponding bends. In some examples, the legs extend perpendicular to the longitudinal axis, and the first side portion and the second side portion may include an outer edge defined by the bend. In some cases, the convex shape has a V-shape in a cross-section along a plane perpendicular to the longitudinal axis.

[0007] In some embodiments, the shield may extend over the outer surface of the tube, and the shield may be configured to protect the tube from physical impact. For example, the shield may extend over the outer surface of the tube, and the shield may be configured to prevent microwaves used in a microwave oven from being incident on the tube. In some cases, the shield extending over the outer surface of the tube has a first portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit from passing through and a second portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit to pass through the shield. In some examples, the first portion and the second portion are configured to prevent microwaves used in a microwave oven from being incident on the tube.

[0008] In some embodiments, the resistive heating element comprises a tube having a wall defining an interior space, an exterior surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall can be configured to allow infrared radiation to pass from the interior space through the wall to the exterior surface. The resistive element can extend in the interior space between the first end and the second end and include a circuit configured to emit infrared radiation in response to a current in the resistive element. In some cases, the circuit can be configured to emit a greater amount of infrared radiation in a first direction than in a second direction opposite to the first direction.

[0009] In some examples, the circuit is configured to emit 20% to 30% more infrared radiation in the first direction than in the second direction. In some cases, the first direction and the second direction are perpendicular to the longitudinal axis. In some embodiments, the circuit defines a convex shape extending between the first end and the second end and facing the first direction. For example, the circuit defines a concave shape extending between the first end and the second end and opposite to the convex shape, wherein the convex shape faces the second direction. In some cases, the convex shape extends a distance of at least 20% of the length of the wall between the first end and the second end. In some embodiments, the circuit has a certain width in a direction perpendicular to the longitudinal axis, and the convex shape extends a distance greater than the width along the longitudinal axis. For example, the convex shape can have a width of at least 90% of the width of the circuit in a direction perpendicular to the longitudinal axis. In some cases, the portion of the circuit defined as the convex shape includes a first planar portion arranged at a certain angle relative to the second planar portion, for example, the circuit can have a joint between the first portion and the second portion. In some examples, a portion of the circuit includes a first side and a second side opposite to each other and has a serpentine shape defined by bends connected by legs, each of the legs extending between respective bends. In some cases, the legs extend perpendicular to the longitudinal axis, and the first side and the second side may have outer edges defined by the bends. In some examples, the circuit has a V-shape in a cross-section along a plane perpendicular to the longitudinal axis.

[0010] In some embodiments, the shield may extend over the outer surface of the tube, wherein the shield is configured to protect the tube from physical impact. In some cases, the shield extends over the outer surface of the tube, wherein the shield is configured to prevent microwaves used in a microwave oven from being incident on the tube. In some examples, the shield extending over the outer surface of the tube has a first portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit in a first direction to pass through the shield and a second portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit in a second direction from passing through. In some cases, the first portion and the second portion are configured to prevent microwaves used in a microwave oven from being incident on the tube.

[0011] In some embodiments, a microwave oven includes: a cooking cavity defined by one or more cavity walls and configured to receive food to be heated; a microwave supply device including a magnetron configured to provide microwaves to be introduced into the cooking cavity to heat the food in the cavity; and a radiant energy heating element positioned in the cooking cavity to be exposed to the microwaves in the cooking cavity. The heating element may include a resistive element extending between a first end and a second end, wherein the resistive element includes a circuit configured to emit infrared radiation in response to a current in the resistive element and a shield extending around the resistive element. The shield may be configured to allow infrared radiation to pass through at least a portion of the shield and prevent microwaves from being incident on the resistive element. In some embodiments, the shield may define an outer surface of the heating element. In some cases, the heating element may be configured as described above and elsewhere herein, for example, configured to include a tube having a wall defining an interior space where the resistive element is positioned, an outer surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall can be configured to allow infrared radiation to pass through the wall from the interior space to the outer surface, for example, the tube can be a quartz tube, and the shield can extend over the outer surface of the tube. In some cases, the shield can completely surround the tube, for example, having a tubular shape extending over the tube of the heating element. In some examples, the shield has a first portion extending along the length of the resistive element and configured to block the infrared radiation emitted by the circuit from passing through and a second portion extending along at least a portion of the length of the resistive element and configured to allow the infrared radiation emitted by the circuit to pass through the shield. In some embodiments, the second portion includes a conductive component having a plurality of openings, the openings being configured to allow infrared radiation to pass through the openings and to block microwaves from passing through the openings. The shield can be electrically grounded to the cavity wall of the cooking cavity, for example, by one or more grounding contacts connected between the shield and the cavity wall. In some cases, the shield can extend along the cavity wall and be spaced apart from the cavity wall, for example, so that the entire exterior of the heating element is exposed to microwaves in the cavity.

[0012] In some cases, the circuit can be configured to emit a greater amount of infrared radiation in a first direction than in a second direction opposite the first direction, and the first direction can extend through the second portion of the shield. For example, the circuit can define a convex shape extending between the first end and the second end and facing the first direction.

[0013] In some cases, the oven may include multiple components for heating food in the cooking cavity. For example, the microwave supply device may include a waveguide for directing microwaves emitted by the magnetron to the cooking cavity. In some cases, the oven may also include a convection element, which includes a fan for moving air into the cooking cavity. The convection element may include a duct having one or more ports, and the fan may be configured to move air in the duct to the one or more ports. In some embodiments, the one or more ports may be configured to output moving air directed to the heating element, for example, so that the air diffuses or otherwise disperses through the heating element.

[0014] In some embodiments, the resistive heating element includes a resistive element extending between a first end and a second end, wherein the resistive element includes a circuit configured to emit infrared radiation in response to a current in the resistive element. A shield may extend over the resistive element, wherein the shield is configured to allow infrared radiation to pass through at least a portion of the shield and prevent microwaves used in a microwave oven from being incident on the resistive element. The shield may define an outer surface of the heating element. A grounding element may be configured to electrically couple the shield and a cavity wall of the oven, for example, to help prevent microwaves from passing through the shield and being incident on the resistive element.

[0015] In some cases, the grounding element includes a body and one or more cavity wall contacts extending from the body. For example, the body can have a circular shape (e.g., a disc shape), and the cavity wall contact can extend radially outward from the periphery of the body. In some cases, one or more cavity wall contacts each form a flexible tab, for example, the tab can be elastically and / or plastically bent. In some embodiments, the grounding element includes a body and one or more shield contacts extending from the body. For example, the body can have an opening (e.g., having an annular or washer shape), and one or more shield contacts can extend from the opening. In some cases, one or more shield contacts each form a flexible tab, for example, the tab can be elastically and / or plastically bent. In some cases, the shield can be configured to fit in the opening of the grounding element to physically contact and electrically contact the grounding element. For example, the shield can include one or more tabs extending from the shield and configured to fit in the opening of the grounding element. In some cases, the shield includes a plurality of tabs extending from the shield in the direction along the length of the shield. For example, a support including at least one opening for receiving at least one of the plurality of tabs may be provided, and a portion of the support may be configured to fit within the opening of the grounding element. In some cases, the support may include a slot for receiving and supporting an end of the resistive element.

[0016] In some embodiments, the heating element may include a tube having a wall defining an interior space, an outer surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall may be configured to allow infrared radiation to pass from the interior space through the wall to the outer surface, the resistive element may extend within the interior space, and the shield may extend over the outer surface. In some cases, the shield has a first portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit from passing through and a second portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit to pass through the shield. For example, the portion of the shield configured to allow infrared radiation to pass through is configured to allow 70% to 90% of the infrared radiation emitted by the circuit to pass through the shield.

[0017] In some embodiments, the resistive heating element includes a resistive element extending between a first end and a second end, wherein the resistive element includes a circuit configured to emit infrared radiation in response to a current in the resistive element. The support may include a groove for receiving and supporting the first end or the second end of the resistive element, wherein the support is configured to engage the resistive element to allow the first end or the second end to move in the groove due to thermal expansion or thermal contraction of the resistive element. For example, the resistive element and the support may be configured so that the resistive element can move longitudinally in the groove, but prevent the resistive element from rotating in the groove. In some cases, the resistive element defines a convex shape at the first end and the second end, and the groove is configured to fit the convex shape closely. For example, the resistive element may have a V-shaped shape at the first end and the second end, and the groove may have a V-shaped shape to receive the first end and / or the second end. In some cases, the convex shape extends from the first end to the second end, and / or the convex shape may face a first direction and the circuit may be configured to emit a greater amount of infrared radiation in the first direction than in a second direction opposite to the first direction.

[0018] In some embodiments, the heating element may include a tube having a wall defining an interior space, an outer surface, and a length extending along a longitudinal axis from a first end of the wall to a second end of the wall. The wall may be configured to allow infrared radiation to pass from the interior space through the wall to the outer surface, wherein the resistive element extends within the interior space. In some cases, a shield extends over the outer surface of the tube, wherein the shield is configured to prevent microwaves used in a microwave oven from being incident on the tube. The shield may define the outer surface of the heating element. In some embodiments, the shield has a first portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit from passing through and a second portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit to pass through the shield. The grounding element may be configured to be electrically coupled to the shield and the cavity wall of the oven, for example, configured to electrically connect the cavity wall to the shield.

[0019] In some embodiments, the support is a first support engaged with the first end of the resistive element, and the heating element may include a second support, the second support including a slot for receiving the second end of the resistive element, wherein the support is configured to engage with the resistive element to allow the second end to move within the slot due to thermal expansion or contraction of the resistive element. In some cases, the resistive element is supported only by the first support and the second support, for example, the resistive element may be suspended between the first support and the second support.

[0020] In some embodiments, the oven includes a cooking cavity defined by one or more cavity walls, configured to receive food to be heated, and having a food support for supporting the food to be heated. A plurality of radiant energy heating elements may be positioned in the cooking cavity, wherein each of the heating elements includes a resistive element extending between a first end and a second end, the resistive element having a circuit configured to emit infrared radiation and visible light in response to a current in the resistive element. The controller may be configured to control the operation of the heating elements in a cooking mode having a first phase and a second phase. In the first phase, when the first heating element is operated to emit infrared radiation and visible light, the second heating element may be operated to emit infrared radiation but not visible light. In the second phase, the first heating element may be operated to stop emitting visible light, and the second heating element may be operated to emit infrared radiation and visible light, such that the second heating element begins to emit visible light when the first heating element stops emitting visible light. The first control phase and the second control phase may be used in different cooking modes, such as a virtual grill mode, in which the heating elements are sequentially or otherwise operated to emit infrared radiation in two or more separate time periods.

[0021] In some embodiments, the heating element can be configured to emit infrared radiation and visible light when the resistive element is above a threshold temperature, and to emit infrared radiation but no visible light when the resistive element is below a threshold temperature. In some cases, during the first stage, the controller operates the second heating element so that the resistive element is within 10% of the threshold temperature before the second stage begins. In this way, the second heating element can be ready to emit visible light in a relatively short period of time because the temperature of the element can be increased to or above the threshold temperature in a short period of time.

[0022] In some cases, a plurality of heating elements are positioned in the cooking cavity such that at least two upper heating elements are positioned above the food support and at least two lower heating elements are positioned below the food support. The first upper heating element may be positioned closer to the front of the cooking cavity than the second upper heating element, and the first lower heating element may be positioned closer to the front of the cooking cavity than the second lower heating element. In some embodiments, the first stage includes: when the first upper heating element is operated to emit infrared radiation and visible light, the second upper heating element is operated to emit infrared radiation but not visible light. The second stage may include stopping the first upper heating element from emitting visible light, and the second upper heating element is operated to emit infrared radiation and visible light, such that the second upper heating element begins to emit visible light when the first upper heating element stops emitting visible light.

[0023] In some cases, the first stage includes: when the upper heating element is operated to emit infrared radiation and visible light, the lower heating element is operated to emit infrared radiation but not visible light, and the second stage includes causing the upper heating element to stop emitting visible light and the lower heating element to operate to emit infrared radiation and visible light, so that the lower heating element begins to emit visible light when the upper heating element stops emitting visible light.

[0024] In some embodiments, the cooking mode is a virtual grill mode in which the plurality of heating elements are each sequentially operated to emit infrared radiation and visible light, and the first stage and the second stage are used to switch between the operation of the heating elements.

[0025] In some embodiments, the oven can be configured to include any of the features described above or otherwise herein. For example, the oven can include a microwave supply device including a magnetron and a waveguide for providing microwaves into the cooking cavity to heat the food in the cavity, and the oven can be configured to simultaneously operate the magnetron and at least one of the plurality of heating elements during the cooking operation. Similarly, the heating element can be configured to include any of the features described above or otherwise herein or a combination of such features.

[0026] In some embodiments, a method of cooking may include providing a cooking cavity defined by one or more cavity walls and configured to receive food to be heated. In a first stage, a first heating element positioned in the cooking cavity may be operated to emit infrared radiation and visible light. Also in the first stage, a second heating element may be operated to emit infrared radiation but not visible light when the first heating element emits infrared radiation and visible light. In a second stage, the first heating element may be operated to stop emitting visible light, and the second heating element may be operated to emit infrared radiation and visible light, such that the second heating element begins to emit visible light when the first heating element stops emitting visible light.

[0027] In some cases, the first heating element and the second heating element can be configured to emit infrared radiation and visible light when the resistive element is above a threshold temperature, and to emit infrared radiation but no visible light when the resistive element is below the threshold temperature. In the first stage, the second heating element can be operated to emit infrared radiation but no visible light by operating the second heating element so that the resistive element is within 10% of the threshold temperature.

[0028] In some cases, the first heating element may be a first upper heating element positioned above a food support in the cooking cavity, and the second heating element may be a second upper heating element positioned above the food support in the cooking cavity. In some cases, the first heating element may be a first upper heating element positioned above a food support in the cooking cavity, and the second heating element may be a second lower heating element positioned below the food support in the cooking cavity. In some embodiments, the method may include operating a plurality of heating elements to sequentially emit infrared radiation and visible light in a virtual grill mode, wherein operation of the first heating element and the second heating element in the first stage and the second stage is used to switch between sequential operation of the heating elements. The method may include operating other components of the oven, such as microwave or convection components, to heat the food in the cooking cavity.

[0029] In some embodiments, the oven includes a cooking cavity defined by one or more cavity walls and configured to receive food to be heated. A radiant energy heating element may be positioned in the cooking cavity, wherein the heating element includes a resistive element extending between a first end and a second end and including a circuit configured to emit infrared radiation in response to a current in the resistive element. The convection element may include a fan and a duct for moving air into the cooking cavity. The duct may have one or more ports positioned adjacent to the heating element and configured to output moving air directed to and impacting the heating element. For example, the one or more ports and the heating element may be configured such that the air flow from the one or more ports is diffused by colliding with the heating element.

[0030] In some cases, one or more ports include openings arranged in the cavity wall and configured along a straight line extending along the length of the heating element. For example, the cavity wall can be a top wall of the cooking cavity, and the heating element can be arranged to extend in a direction parallel to the plane of the top wall and below the plane of the top wall. The cooking cavity can include a food support located in the cooking cavity, the food support being positioned below the top wall and the heating element. In some cases, the heating element can be located between the one or more ports and the food support, and the one or more ports can be configured to direct air downward toward the food support. In some embodiments, the duct includes an air intake port that draws air from the cooking cavity into the duct, wherein the air intake port is located at a side wall or bottom wall of the cooking cavity. In some cases, the convection element includes a heater configured to heat the air in the duct, for example, the heater can be a resistive heater positioned in the duct downstream of the fan.

[0031] In some cases, the oven includes a microwave supply device including a magnetron and a waveguide for providing microwaves into the cooking cavity to heat food in the cavity. The oven can be configured to operate the magnetron, fan, and heating element simultaneously during a cooking operation.

[0032] The radiant energy heating element can have any of the features described above or otherwise herein, including any combination of such features that are not mutually exclusive. As just one example, the heating element can include a shield extending around the resistive element, wherein the shield is configured to allow infrared radiation to pass through at least a portion of the shield and prevent microwaves from being incident on the resistive element. A portion of the shield configured to block infrared radiation can be configured to be impacted by air exiting one or more ports.

[0033] In some embodiments, the method of cooking includes providing a cooking cavity defined by one or more cavity walls and configured to receive food to be heated. Infrared radiation can be emitted from a heating element positioned in the cooking cavity, and an air flow can be directed from a port adjacent to the heating element so that the air flow impacts the heating element. In some cases, the air flow can be diffused by colliding with the heating element. In some embodiments, the air flow can be discharged from an opening arranged in the cavity wall along a straight line extending along the length of the heating element. In some examples, the cavity wall can be a top wall of the cooking cavity, and the heating element can be arranged to extend in a direction parallel to the plane of the top wall and below the plane of the top wall.

[0034] In some embodiments, the air flow can be exhausted from the opening in a direction toward the food support in the cooking cavity, and the heating element can be located between the one or more ports and the food support. In some cases, the air can be drawn into an air intake port that is fluidly connected to the port, and the air intake port can be located at a side wall or bottom wall of the cooking cavity. In some examples, the air can be heated before the air is exhausted from the port.

[0035] In some examples, microwaves can be provided to the cooking cavity during the cooking operation to heat the food in the cavity while the heating element emits infrared radiation in the cooking cavity. The microwaves can be prevented from being incident on the heating element by a shield extending around the heating element, wherein the shield is configured to allow infrared radiation to pass through at least a portion of the shield and prevent the microwaves from being incident on the heating element. As described above, the infrared heating element can be configured to have any feature or combination of features described herein. As an example, a quartz tube of the heating element can be blocked from air flow from one or more ports by using a first portion of the shield positioned between the tube and one or more ports. However, infrared radiation can be allowed to pass through a second portion of the shield opposite to the first portion.

[0036] As described herein, visible light can be in the wavelength range of 570 nanometers to 800 nanometers and is emitted as a result of the heating element operating in a manner that emits infrared light at a desired wavelength range and radiant flux to heat the food item. Thus, the visible light can confirm to the user that the food item is being cooked or otherwise heated in a particular manner, such as quickly, evenly, and without drying.

[0037] Various additional aspects will be described in the following description. These aspects may relate to individual features and combinations of features. It should be understood that the foregoing general description and the following detailed description are only exemplary and explanatory, rather than limiting the broad inventive concepts upon which the embodiments disclosed herein are based. To the extent that the various aspects are not mutually exclusive, these aspects may be combined together or used alone in any suitable manner in any suitable embodiment. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is an upper left front perspective view of a cooking appliance arranged as an oven in an illustrative embodiment.

[0039] Figure 2 yes Figure 1 A front perspective view of the lower right side of an oven.

[0040] Figure 3 With part of the housing removed Figure 1 3D image of the upper right front perspective view of an oven.

[0041] Figure 4 With part of the housing removed Figure 1 3D image of the upper left rear view of the oven.

[0042] Figure 5 This is when the microwave supply device and convection element are removed. Figure 1 3D image of the upper left front perspective view of an oven.

[0043] Figure 6 It is along Figure 5 A lower left front perspective cross-sectional view taken along line 6-6 in FIG.

[0044] Figure 7 is an upper perspective view of a heating element configuration in an illustrative embodiment.

[0045] Figure 8 yes Figure 7 A bottom perspective view of the heating element configuration.

[0046] Fig. 9 yes Figure 7 and Figure 8 A close-up view of the top side of the heating element configuration.

[0047] Fig.10 yes Figure 7 and Figure 8 A close-up view of the underside of the heating element configuration.

[0048] Fig.11 and Fig.12 yes Figure 7 and Figure 8 An enlarged perspective view of a heating element configuration in a partially assembled state. DETAILED DESCRIPTION

[0049] Various embodiments will be described in detail with reference to the accompanying drawings, wherein like reference numerals represent like parts and components. Reference to various embodiments does not limit the scope of the claims. In addition, any examples set forth in this specification are not intended to be limiting, but merely set forth some of the many possible embodiments of the claims.

[0050] Figure 1 and Figure 2 A perspective view of an illustrative cooking appliance 1, such as an oven, is shown, which includes a housing 10 that at least partially encloses a cooking cavity 12 defined by one or more cavity walls 121-124. In use, food is placed on a food support 16 within the cooking cavity 12 and heated by the oven 1, such as by one or more heating elements 2. A user can interact with the user interface 11 to provide cooking instructions to the oven 1 (e.g., cooking time, temperature, mode, food type, etc.) and / or receive information from the oven 1 (e.g., remaining cooking time, current temperature, cooking mode, etc.). In some embodiments, the oven 1 may include other or additional components for heating food in the cavity 12, such as a convection element 3 discussed in more detail below (e.g., see Figure 3 ) and / or microwave supply device 4 (see, for example, Figure 4 ). In some examples, food support 16 includes one or more grooves or other features on side walls 122, 123 of cavity 12 that are configured to engage with and support a food rack, tray, or the like (not shown for clarity) of food support 16. For example, side portions of a food rack or tray may engage with grooves at side walls 122, 123 so as to be suspended in cooking cavity 12. Other arrangements for food support 16 are possible, such as turntable supports commonly found in microwave ovens, a pressure plate on bottom wall 124 of cavity 12, and the like. Oven 1 also includes door 14 or other components (see Figure 5 ), the door 14 or other components can be opened to allow the user to enter the cavity 12 to place food and / or take out food, and can be closed to seal the food in the cavity 12. Figure 1 and Figure 2, the door is removed for clarity, but a hinge 13 is shown to which the door 14 can be mounted. In some embodiments, for example, the door 14 can pivot about a horizontal axis at the lower front side of the cavity 12 so that the door can pivot downward to open. In other examples, the door 14 can open around a vertical hinge or other configuration. The door 14 and the cavity walls 121 to 124 can be arranged to block microwaves from leaving the cavity and / or help keep heat and / or gases in the cavity 12. For example, the door 14 and / or the cavity walls 121 to 124 may include a conductive metal panel and / or mesh configured to prevent microwaves from escaping the cavity 12.

[0051] In some embodiments, the oven 1 includes one or more heating elements 2 that emit infrared radiation in the cooking cavity 12. Figure 1 and Figure 2 In the embodiment of the present invention, two heating elements 2 are positioned at the bottom of the cooking cavity 12 below the food support 16, and four heating elements 2 are positioned at the top of the cavity 12 above the food support 16. However, other arrangements with any suitable number of heating elements 2 at the top, bottom, back wall, side wall, or door of the cooking cavity 12 are also possible. In some cases, the heating element 2 can be completely positioned in the cavity 12, for example, surrounded by the air in the cavity 12 and spaced apart from the adjacent walls. Therefore, the entire outer surface of the heating element 2 can be exposed to the microwaves in the cavity 12. The infrared radiation emitted by the heating element 2 can be at least partially directed to the food in the cavity 12 and heat the food.

[0052] In some embodiments, the heating element 2 can be controlled by the controller of the oven 1 to operate in a virtual grill mode. In a conventional grill, the food is rotated or otherwise moved while in the cooking cavity and exposed to a fixed heat source. In the virtual grill mode, the food does not need to be moved in the cavity 12, but the heating element or other heat source can be moved or operated so that heat is emitted from different locations at different times relative to the food in the cavity 12. As an example, Figure 1 and Figure 2 The heating elements 2 in the oven 2 may be operated such that a first group of one or more heating elements 2 are energized to emit infrared radiation, and then subsequently another group of heating elements 2 are energized, and so on. This sequential operation of multiple groups of heating elements 2 may simulate the movement of food in the cavity 12. In some embodiments, a first heating element 2 may be turned on or otherwise operated to emit infrared radiation, and after a period of time, the first heating element 2 may be turned off and a second heating element 2 may be turned on. Then, the second heating element 2 may be turned off and a third heating element 2 may be turned on, and so on. Figure 1 and Figure 2As an example, the order in which the heating elements 2 are activated can be controlled to provide a simulation of rotating food, for example, by activating a first heating element 2 located at the top front of the cavity 12, then activating a second heating element 2 located at the top of the cavity 12 immediately behind the first heating element 2, then activating a third heating element 2 immediately behind the second heating element 2, then activating a fourth heating element 2 immediately behind the third heating element 2, then activating a fifth heating element 2 located at the bottom rear of the cavity 12, then activating a sixth heating element 2 located at the bottom front of the cavity 12, then activating the first heating element 2, and so on. The heating elements 2 need not be operated one at a time, but rather any group of two or more heating elements may be turned on during any step or stage of the control cycle.

[0053] In some embodiments, it may be desirable to operate the heating elements 2 not only in a multi-phase cycle or other sequence, but also to provide a visible light output from the heating elements 2 so that the user can see that the cooking program is being executed. Infrared heating elements emit infrared light, which is generally not in the visible spectrum, so the user cannot always see that the heating elements are operating. By making the heating elements 2 emit visible light as well as infrared light, the user can see that the heating elements 2 are operating. Thus, for example, each heating element 2 that is energized can also emit visible light in addition to infrared radiation during at least a portion of its operation. In addition, in some embodiments, it may be desirable to operate the heating elements in sequence (e.g., operate a group of heating elements 2, then operate another group of heating elements, and so on), so that the first group of heating elements 2 that are powered off stops emitting visible light at the same time as the second group of heating elements 2 that are powered on starts emitting visible light. This can give the user a feeling that when the first group of heating elements 2 stops operating, the second group of heating elements 2 immediately starts its heating operation. It should also be noted that the same heating element 2 can be turned on during two or more consecutive steps in the cycle.

[0054] In some cases, the radiant energy heating element 2 does not immediately emit visible light when it is enabled in a relatively cold state, such as when the heating element 2 is turned on or otherwise powered. That is, some heating elements 2 begin to emit infrared radiation before emitting visible light, because the heating element 2 must be heated to a threshold temperature to emit visible light, and the threshold temperature for emitting visible light can be higher than the threshold temperature for emitting infrared radiation. Therefore, if the first heating element 2 is powered off or otherwise reduced in power while the second heating element 2 is powered on, the first heating element 2 may stop emitting visible light long before the second heating element 2 begins to emit visible light, because the second element 2 needs time to be sufficiently heated to emit visible light. In some embodiments, the heating elements 2 in the oven can be controlled so that the first heating element 2 will stop emitting visible light at the same time as the second heating element 2 begins to emit visible light. This can be accomplished by preheating or powering the second heating element 2 so that the second heating element 2 emits infrared radiation but does not emit visible light while the first heating element 2 is still emitting visible light. In this way, when the power to the first heating element 2 is reduced, the second heating element 2 will be ready to heat up relatively quickly to the point where it emits visible light as the first heating element 2 stops emitting visible light. In some cases, the second heating element 2 may be energized so that it is close to, but below, a threshold temperature at which it emits visible light before the first heating element 2 is de-energized or stops emitting visible light. In this way, the second heating element 2 only needs to increase its temperature by a relatively small amount in a relatively short period of time to begin emitting visible light.

[0055] In some embodiments, the controller of the oven can be configured to control the operation of the heating element in a cooking mode having a first stage and a second stage. In the first stage, when the first heating element is operated to emit infrared radiation and visible light, the second heating element is operated to emit infrared radiation but not visible light. This can be considered as a preheating or preparation stage of the second heating element, which makes the second heating element ready to emit visible light in a relatively short period of time. In the second stage, the first heating element is operated to stop emitting visible light, for example, by interrupting or otherwise reducing the power of the heating element, and the second heating element is operated to (for example, by increasing the power of the heating element) emit infrared radiation and visible light, so that the second heating element starts to emit visible light when the first heating element stops emitting visible light. The timing required to achieve visible light emission can be achieved in different ways and may depend on the heating element. For example, in some cases, the second heating element can be energized at a fixed power level, and the power of the first heating element can be interrupted or otherwise reduced at a later time, so that the first heating element stops emitting visible light when the second heating element starts emitting visible light. In other cases, the second heating element may be operated at a relatively low power level, for example, at a power level at which the second heating element reaches a temperature close to but below a threshold temperature at which the heating element emits visible light (e.g., a temperature within about 10% of the threshold temperature), and then operated at a higher power level approximately when the power to the first heating element is reduced. Such power level regulation may be performed using different control means, such as, for example, using pulse width modulation or other control means to regulate the voltage and / or current of the electrical power applied to the heating element.

[0056] As will be appreciated, the two-stage operation for switching between heating elements or groups of heating elements may be used for a virtual grill cooking mode or any other cooking mode. Thus, a two-stage control may be employed when sequentially operating the heating elements to emit infrared radiation and visible light, with the first and second stages being used to switch between operation of the heating elements. It is also noted that in addition to infrared radiation from the heating elements 2, other heat sources in the oven, such as microwave energy, heated air or convection heating systems, etc., may also be used to heat food.

[0057] As described above, in some embodiments, oven 1 may include convection elements 3 that may heat air and move the heated air around the cavity, for example, to help cook food in the cavity. Figure 3 As can be seen in FIG. 1 , the oven 1 may include a convection element 3 including a fan 31 and a duct 32 for moving air into the cooking cavity 12. The duct 32 may be provided as shown in FIG. Figure 11 and / or at the bottom wall 124 for drawing air from the cavity 12 into the duct 32. The fan 31 can cause air to move through the duct 32 over the top wall 121 of the cavity 12, such as into a booster chamber or other portion of the duct 32, so that the air can be directed back into the cavity 12. In some cases, the convection element 3 may include a heater 33, such as a resistive heater, which heats the air as it moves through the duct 32. In some embodiments, the duct 32 can have one or more exhaust ports 34, each of which is positioned adjacent to the heating element 2 in the cavity 12 and is configured to output moving air that is directed and impinges on the heating element 2. For example, as can be seen in FIG. Figure 5 As can be seen in FIG. 1 , air can flow from the duct 32 into a plenum or space above the plurality of exhaust ports 34. Figure 2 and Figure 6 As observed in FIG. 1 , air may exit the exhaust port 34 and be directed to the corresponding heating element 2 below the port 34. The port 34 and the heating element 2 may be configured such that the air flow from the port 34 is diffused by collision with the heating element 2. This may help prevent the air from the port 34 from flowing directly into contact with the food in the cavity 12, but rather create turbulence, interrupt the air flow, or otherwise diffuse the air flow from the port 34.

[0058] In some cases, port 34 comprises an opening disposed in a cavity wall, such as top wall 121, and configured along a straight line extending along the length of heating element 2. In some cases, heating element 2 can be arranged to extend in a direction parallel to and below the plane of top wall 121, and food support 16 can be positioned below top wall 121 and heating element 2. Thus, in some cases, heating element 2 can be located between one or more of ports 34 and food support 16, for example, wherein the ports are configured to direct air downward toward food support 16. Other arrangements of ports 34 and heating element 2 can be employed, wherein air output from ports 34 is diffused or otherwise interrupted in flow through heating element 2. For example, ports 34 can be disposed at side walls 122, 123, and / or bottom wall 124, and heating element 2 can be arranged to extend along side walls 122, 123, and / or bottom wall 124 (e.g., Figure 1 and Figure 3 ). Thus, the configuration of ports exhausting air directed to the heating elements is not limited to use at the top wall of the cooking cavity 12. The ports 34 may have any suitable size and / or shape, such as circular, oval (optionally extending along the length of the corresponding heating element), etc.

[0059] In some embodiments, the oven may include a microwave supply for providing microwave energy into the cooking cavity to heat food. As with other cooking energy sources, the microwave supply may be used alone or in any suitable combination with other sources, such as one or more heating elements and / or convection elements. Figure 4 As can be seen in FIG. 1 , the microwave supply device 4 may include a magnetron 41 for generating and emitting suitable microwave energy and a waveguide 42 for introducing microwave energy into the cooking cavity 12. The magnetron 41 and other components of the oven (such as the fan 31, the heating element 2, the user interface 11, etc.) may be controlled by a controller 15 arranged to perform any suitable input / output and other control functions. The walls 121 to 124 and the door 14 (see FIG. 1 ) defining the cooking cavity 12 Figure 5 ) can be configured to help keep the microwave energy in the cavity 12 so that the microwave energy is not emitted from the cavity 12 or is emitted at a relatively low level. Typically, this is accomplished by using metal wall elements (whether perforated or not) at the walls 121 to 124 and / or the door 14.

[0060] In some embodiments, the heating element 2 is exposed to microwave energy within the cavity 12, for example, the heating element 2 can be positioned within the cavity defined by the walls 121 to 124 so that the air in the cavity can flow around the heating element 2. This is in contrast to ovens that employ both microwave heating elements and radiant heating elements, in which the heating element is positioned in a cavity wall recess behind a microwave blocking panel or other element. Since the heating element 2 is exposed to microwave energy in some embodiments, for example, in the cavity 12 at a portion along its entire length, measures must be taken to help prevent microwave energy from leaving the cavity 12 via the heating element 2. In some existing ovens, a choke or other element is arranged outside the cavity 12, above the end of the heating element 2, to help control the microwaves in the cavity. However, this approach can be cumbersome and provide less than ideal microwave control. In some embodiments, the heating element exposed to the cooking cavity can have a shield extending around the infrared radiation emitting resistive element of the heating element. The shield can define the outer surface of the heating element and be configured to allow, for example, infrared radiation emitted by the resistive element to pass through at least a portion of the shield and prevent microwaves from being incident on the resistive element. Thus, the shield can prevent microwaves from leaving the cavity via the resistive element or other portions of the heating element within the shield, while allowing infrared energy to freely pass through at least a portion of the shield for cooking purposes. In some cases, the shield can provide physical protection for heating element components within the shield, such as a quartz tube in which the resistive element resides. Thus, in some cases, a heating element with a shield can be used in an oven that does not include a microwave supply.

[0061] Figure 7 and Figure 8Top and bottom perspective views of an illustrative heating element 2 at different levels of assembly are shown. In some embodiments, the heating element 2 includes a resistive element 23 extending between a first end and a second end and including a circuit configured to emit infrared radiation in response to a current in the resistive element. For example, a control circuit can be connected to the first and second ends of the resistive element so that a voltage can be applied across the first and second ends and a current can flow through the resistive element 23. The current can cause the circuit of the resistive element 23 to heat and emit infrared radiation. In some cases, the resistive element 23 can be configured to also emit visible light, for example, when one or more portions of the resistive element 23 are above a threshold temperature. The circuit of the resistive element that emits infrared radiation can be configured in different ways. In some embodiments, the circuit includes a metal or other conductive portion having a serpentine shape formed by bends 231, which are connected by legs 232 to form a continuous "S" shape. The legs 232 can be arranged as shown. Figure 7 , extending perpendicular to the length or longitudinal axis of the resistor element 23 or extending at other angles. In some embodiments and as may be Figure 7 As observed in FIG. 2 , the circuit includes two parallel portions or sides connected at a joint 233. In some cases, the two sides of the circuit can each be planar and joined at one edge of the respective planes at the joint 233. In some embodiments, each of the two sides of the circuit can have a serpentine shape, the serpentine shape including a continuous "S" shape extending along the length of the resistive element 23. The serpentine shape can be formed by bends 231 connected by legs 232 extending between the respective bends 231. The inner bends 231 of the two parallel sides are connected at the joint 233 and connected by the legs 232 to the outer bends 231 that form the outer edges of the two portions of the circuit. Therefore, the current in each of the two sides can flow outward from the joint 233, through the legs 231 to the outer bend 231, and then inward via another leg 231 to the inner bend 231 and the joint 233, and so on. This arrangement can help balance the current flow in the two parallel sides of the circuit and / or allow portions of both sides to continue to operate to emit infrared radiation if the legs 232 or the outer bend 231 are damaged and electrical continuity is lost. The shape of the circuit can be made in different ways, such as by stamping or machining a flat sheet of metal or other conductive material to form an opening defining the bend 231 and the legs 232, such as forming a repeating pattern in the form of an ellipse or other closed loop, so that adjacent loops are joined at the central area of ​​the loop at the joint 233.

[0062] In some embodiments, a portion of the circuit of the resistive element 23 is defined as a convex shape, such as a convex shape that extends along the length of the resistive element 23. Such a configuration may provide benefits such as providing physical strength and / or rigidity to the circuit (e.g., by increasing the moment of inertia of the circuit), and / or by enabling the resistive element to emit a greater amount of infrared radiation in a first direction than in an opposite second direction. Figure 7 As shown in , the resistor element 23 can define a V-shape in a cross-section relative to the length or longitudinal axis of the resistor element 23. However, other convex shapes are also possible, such as a U-shape, a W-shape, a semicircular shape, an irregular shape, or other shapes. In some embodiments, the convex shape can extend a distance of at least 20%, at least 50%, at least 75%, and / or at least 90% of the length of the resistor element 23 between the first end and the second end of the resistor element 23. In some cases, the circuit can have a certain width in a direction perpendicular to the longitudinal axis (e.g., the distance between the outer bends 231), and the convex shape can extend a distance greater than the width along the longitudinal axis. In some embodiments, the convex shape can have a width of at least 90% of the width of the circuit in a direction perpendicular to the longitudinal axis, for example, in Figure 7 In some cases, the circuit may define a concave shape extending between the first end and the second end and opposite the convex shape. Thus, for example, the convex shape may face a first direction, and the concave shape may face a second direction opposite the first direction. In some cases, the circuit may be configured to emit a greater amount of infrared radiation in the first direction than in the second direction. For example, the circuit may be configured to emit 20% to 30% more infrared radiation in the first direction than in the second direction. This feature may make more efficient use of energy when heating food in the cooking cavity 12. For example, the heating element 2 may be positioned to extend along a wall of the cavity 12, such as the top wall 121 or the bottom wall 124, and the heating element 2 may be configured so that the convex shape faces the food support 16. This enables the heating element 2 to provide a relatively higher level of radiant energy to the food than would otherwise be provided. However, in some embodiments, the convex shape need not face the food support 16, but may be used to help provide physical support to the resistive element 23. For example, a resistive element 23 having a V-shape can be oriented so that the convex shape (or the bottom of the V-shape) faces downward, regardless of where the heating element 2 is located in the cavity 12. This can help prevent the resistive element 23 from sagging or bending downward during operation because this orientation can provide increased strength compared to other orientations.

[0063] In some embodiments, the portion of the circuit defined as a convex shape includes a first planar portion arranged at an angle relative to the second planar portion. For example, a first portion having a set of bends 231 and legs 232 on one side of the joint 233 can be arranged in a first plane, and a second portion having a set of bends 231 and legs 232 on the other side of the joint 233 can be arranged in a second plane at an angle to the first plane. The first plane and the second plane meet at the joint 233 and can be arranged at an angle to each other, for example, to define a V-shaped shape. The first portion of the circuit located on the first side of the joint 233 and the second portion of the second side of the joint 233 can be opposite to each other and can each have a serpentine shape. For example, the current can flow through a tortuous path including the legs 232 and the bend 231 on the first side of the joint 233, and can flow through another tortuous path of the legs 232 and the bend 231 on the second side of the joint 233.

[0064] In some embodiments, heating element 2 can have a tube 22 including a wall defining an interior space, with resistive element 23 positioned in and extending in the interior space. Tube 22 can have an outer surface and a length extending along a longitudinal axis from a first end of the tube wall to a second end of the tube wall. The tube wall can be configured to allow infrared radiation to pass from the interior space through the wall to the outer surface and to the food support 16. In some cases, the tube can be a quartz tube or other material that is generally transparent to infrared radiation. Tube 22 can be electrically insulating, for example, to help prevent resistive element 23 from forming an electrical short circuit by contacting another conductive component.

[0065] In some cases, the shield 21 may extend over the outer surface of the tube 22, or over the resistive element 23 if the tube 22 is not provided. The shield 21 may be configured to allow infrared radiation to pass through at least a portion of the shield and prevent microwaves used in a microwave oven from being incident on the tube 22 and / or the resistive element 23. As mentioned above, the resistive element may provide a path for microwaves to leave the cooking cavity because the resistive element is typically made of a conductive material and configured so that microwaves can be transmitted out of the cavity through the resistive element. However, by providing the shield 21 over the resistive element 23, microwaves may be prevented from contacting the resistive element 23. Additionally or alternatively, the shield 21 may provide physical protection for the heating element 2, for example, to help prevent contact with and / or damage to the resistive element 23 and / or the tube 22. In some cases, the shield 21 may completely surround the tube 22 and / or the resistive element 23, for example, the shield 21 may have a tubular shape that fits over the tubular shape of the tube and defines the outer surface of the heating element.

[0066] In some embodiments, shield 21 may have a first portion extending along the length of resistive element 23 and configured to block infrared radiation emitted by the circuit from passing therethrough and a second portion extending along at least a portion of the length of the resistive element and configured to allow infrared radiation emitted by the circuit to pass therethrough. For example, Figure 7 and Figure 8 As shown in FIG. 2 , the shield 21 may have a solid (eg, Figure 7 and / or air flow, and having one or more openings for allowing infrared radiation to pass freely therethrough (e.g., in the form of a partially cylindrical shell visible in FIG. 1 ). Figure 8 In some cases, the first portion of the shield that blocks infrared radiation from passing through can be positioned adjacent to or opposite to the cavity wall, for example, the solid portion of the shield 21 can be positioned opposite to the top wall 121 of the cavity 12, and the second portion that allows infrared radiation to pass through can be positioned facing the food support 16. This can help direct the infrared radiation toward the food in the cavity 12 and help prevent heating of the cavity wall. In addition, in the case where the resistive element 23 is capable of emitting a greater amount of infrared radiation in one direction than in another direction, the second portion of the shield 21 that allows infrared radiation to pass through can be aligned with the direction of the greater amount of infrared radiation. For example, the convex portion of the resistive element 23 can face the second portion of the shield 21. In some cases, despite having an opening in the shield for allowing infrared radiation to pass through, the shield 21 can still prevent microwaves from contacting the tube 22 or the resistive element 23. For example, the second portion can include a conductive member (e.g., a mesh or perforated metal plate) having a plurality of openings, the size of the openings being configured to allow infrared radiation to pass through the openings and to prevent microwaves from passing through the openings. In some cases, the portion of the shield configured to allow infrared radiation to pass therethrough may be configured to allow 70% to 90% of the infrared radiation emitted by the circuit to pass through shield 21 .

[0067] In the case where the heating element 2 is exposed to microwaves in the cooking cavity 12, for example, the heating element 2 is spaced apart from the wall of the cavity 12 so that the microwaves can surround the heating element 2, the shield 21 can be electrically grounded to the cavity wall to help prevent the microwaves from leaving the cavity 12 via the resistive element 23 or other components of the heating element 2. In some cases, the heating element 2 includes a grounding element 24 for electrically connecting the opposite ends of the shield 21 to the corresponding cavity wall. In some embodiments, the grounding element 24 is configured to fit or otherwise be received in a recess 125 of the cavity wall (e.g., see Figure 5 ), thereby making electrical contact with the cavity wall. As an example, the recess 125 can be formed to have a cylindrical shape, and the grounding element 24 can be fitted into the corresponding recess 125 by friction or interference fit. In some cases, the grounding element 24 can provide mechanical or physical support for the heating element 2 on the cavity wall. Fig. 9 and Fig.10 As can be seen in FIG. 1 , the grounding element 24 is assembled to the end of the heating element 2 together with the support 25. For example, after the resistance element 23 is positioned in the tube 22 and the shield 21 is positioned over the tube 22, the support 25 can be fitted to the ends of the tube 22 and the shield 21. Thereafter, the grounding element 24 can be fitted to the support 25 so as to be in electrical contact with the shield 21.

[0068] Fig.11 and Fig.12A close-up view of the end of the shield 21, the support 25, and the grounding element 24 is shown. The end of the shield 21 may include a plurality of tabs 211, for example, extending from the end of the shield in a direction along the length of the shield 21 or its longitudinal axis. The support 25 includes a plurality of openings 251 configured to receive corresponding tabs 211, so that when the support 25 is mounted on the shield 21, the tabs 211 extend through the openings 251 and emerge from the opposite side of the support 25. The grounding element 24 includes a body (e.g., having a circular or annular shape) having an opening sized to fit over the end of the shield 21 and the tabs 211. In some cases, a portion of the support 25 also extends through the opening of the grounding element 24. The grounding element 24 includes a plurality of shield contacts 242, each of which forms a tab, is flexible, and extends from the body at the opening. The shield contact portion 242 is configured to contact one or more tabs 211 of the shield 21 to electrically connect the ground element 24 and the shield 21. The tab 211 and / or the shield contact portion 242 can be resilient so that the tab 211 and the contact portion 242 contact each other by spring bias or elastic bias to help maintain the physical connection and electrical connection between the tab 211 and the contact portion 242. The contact portion 242 can extend radially inward from the opening of the body of the ground element 24 to help ensure proper contact with the tab 211. The opening 251 of the support member 25 can provide physical support for the tab 211, for example, to help keep the tab 211 in a suitable orientation and position to connect with the contact portion 242. The ground element 24 also includes a cavity wall contact portion 241 extending from the body, for example, from the periphery of the body in a radially outward direction. For example, the body can have a circular or annular shape, and the contact portion 241 can extend radially outward from the periphery of the circular or annular shape. The contact portion 241 may be resilient, for example, deformable when inserted into the recess 125 of the cavity wall so as to form suitable electrical and physical contact with the recess 125. For example, the outer edge of the contact portion 241 may define a circular shape that is larger than the size of the recess 125 into which the grounding element 24 is inserted. The contact portion 241 may be bent inwardly to be received in the recess 125 and maintain contact with the inner surface of the recess 125. The engagement of the grounding element 24 at the opposite ends of the heating element 2 may provide mechanical support for the heating element 2 and provide electrical grounding for the shield 21. The grounding element 24 may be formed from a sheet of metal, for example, stamped to form the body and the contact portions 241, 242.

[0069] If you can Fig.11 and Fig.12As observed in FIG. 2 , the support 25 may include a groove 252 for receiving the end of the resistive element 23. In some embodiments, the groove 252 may simulate a convex shape, such as a V-shape, defined by the resistive element 23 and may help prevent the resistive element from rotating relative to the support 25 about the longitudinal axis of the heating element. In some cases, the groove 252 and the end of the resistive element 23 may be configured so that the end of the resistive element may slide along its length in the groove 252, for example, due to thermal expansion and / or thermal contraction. This may help reduce stress on the resistive element 23, the support 25, and / or other portions of the heating element 2 due to temperature changes. The support 25 may be made of an electrically insulating material such as a polymer, ceramic, or other material. In some cases, the support 25 may provide the only physical support for the resistive element 23, for example, the resistive element 23 is suspended at its first and second ends. The first and second ends of the resistive element 23 may extend from the support 25 to allow electrical connection to a control circuit that provides electrical energy to the heating element 2.

[0070] The controller 15 including the user interface 11 may include a programmed processor and / or other data processing device and suitable software or other operating instructions executed by the data processing device, one or more memories (including non-transitory storage media that can store software and / or other operating instructions), sensors, input / output interfaces, communication devices (e.g., including transceivers, radios, gateways, interfaces, etc. that are appropriately programmed or otherwise configured to communicate using any suitable wired or wireless protocol), buses or other links, displays, switches, relays, triacs, batteries or other power or supply devices, or other components necessary to perform the desired input / output, control or other functions. The user interface 11 may be arranged in any suitable manner and include any suitable components for providing information to and / or receiving information from a user, such as buttons, a touch screen, a voice command module (including a microphone for receiving audio information from a user and suitable software for interpreting the audio information as voice commands), a visual display, one or more indicator lights, a speaker, etc.

[0071] The various embodiments described above are provided by way of illustration only and should not be construed as limitations on the claims appended hereto. Those skilled in the art will readily appreciate that various modifications and changes may be made without following the example embodiments and applications illustrated and described herein, and without departing from the true spirit and scope of the appended claims.

Claims

1. A resistance heating element, comprising: a tube having a wall defining an interior space, an exterior surface, and having a length extending along a longitudinal axis from a first end of the wall to a second end of the wall, the wall being configured to allow infrared radiation to pass from the interior space through the wall to the exterior surface; as well as A resistive element extends in the interior space between the first end and the second end, the resistive element including a circuit configured to emit infrared radiation in response to a current in the resistive element, the circuit defining a convex shape extending between the first end and the second end.

2. The heating element according to claim 1, wherein The convex shape extends a distance of at least 20% of the length of the wall between the first end and the second end.

3. The heating element according to claim 1, wherein The circuit has a width in a direction perpendicular to the longitudinal axis, and the convex shape extends a distance greater than the width.

4. The heating element according to claim 3, wherein The convex shape has a width in a direction perpendicular to the longitudinal axis of at least 90% of a width of the circuit.

5. The heating element according to claim 1, wherein The convex shape faces in a first direction, and the circuit is configured to emit a greater amount of infrared radiation in the first direction than in a second direction opposite the first direction.

6. The heating element according to claim 1, wherein The circuit defines a concave shape extending between the first end and the second end and opposite the convex shape.

7. The heating element according to claim 6, wherein The convex shape faces in a first direction and the concave shape faces in a second direction opposite the first direction, and wherein the circuit is configured to emit a greater amount of infrared radiation in the first direction than in the second direction.

8. The heating element according to claim 7, wherein The circuit is configured to emit 20% to 30% more infrared radiation in the first direction than in the second direction.

9. The heating element according to claim 1, wherein The portion of the circuit defining the convex shape includes a first planar portion disposed at an angle relative to a second planar portion.

10. The heating element according to claim 9, wherein The portion of the circuit has a junction between a first portion and a second portion.

11. The heating element according to claim 1, wherein The portion of the circuit defining the convex shape includes a first side and a second side opposite each other, each of the first side and the second side having a serpentine shape defined by bends connected by legs, each of the legs extending between a respective bend.

12. The heating element according to claim 11, wherein The legs extend perpendicular to the longitudinal axis.

13. The heating element according to claim 11, wherein The first side portion and the second side portion include outer edges defined by the bend.

14. The heating element according to claim 1, wherein The convex shape has a V-shape in a cross-section along a plane perpendicular to the longitudinal axis.

15. The heating element of claim 1, further comprising a shield extending over an outer surface of the tube, the shield being configured to protect the tube from physical impact.

16. The heating element of claim 1, further comprising a shield extending over an outer surface of the tube, the shield being configured to prevent microwaves used in a microwave oven from being incident on the tube.

17. The heating element of claim 1 further comprising a shield extending over the outer surface of the tube, the shield having a first portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit from passing therethrough and a second portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit to pass through the shield.

18. The heating element according to claim 17, wherein The first portion and the second portion are configured to prevent microwaves used in a microwave oven from being incident on the tube.

19. A resistance heating element, comprising: a tube having a wall defining an interior space, an exterior surface, and having a length extending along a longitudinal axis from a first end of the wall to a second end of the wall, the wall being configured to allow infrared radiation to pass from the interior space through the wall to the exterior surface; as well as A resistor element extending in the interior space between the first end and the second end, the resistor element including a circuit configured to emit infrared radiation in response to a current in the resistor element, the circuit configured to emit a greater amount of infrared radiation in a first direction than in a second direction opposite to the first direction.

20. The heating element of claim 19, wherein The circuit is configured to emit 20% to 30% more infrared radiation in the first direction than in the second direction.

21. The heating element of claim 19, wherein The first direction and the second direction are perpendicular to the longitudinal axis.

22. The heating element of claim 19, wherein The circuit defines a convex shape extending between the first end and the second end and facing in the first direction.

23. The heating element of claim 22, wherein The circuit defines a concave shape extending between the first end and the second end and opposite the convex shape, the concave shape facing in the second direction.

24. The heating element of claim 22, wherein The convex shape extends a distance of at least 20% of the length of the wall between the first end and the second end.

25. The heating element of claim 22, wherein The circuit has a width in a direction perpendicular to the longitudinal axis, and the convex shape extends along the longitudinal axis a distance greater than the width.

26. The heating element of claim 25, wherein The convex shape has a width in a direction perpendicular to the longitudinal axis of at least 90% of a width of the circuit.

27. The heating element of claim 22, wherein: The portion of the circuit defining the convex shape includes a first planar portion disposed at an angle relative to a second planar portion.

28. The heating element of claim 27, wherein The circuit has a junction between the first portion and the second portion.

29. The heating element of claim 19, wherein A portion of the circuit includes a first side and a second side opposite to each other and has a serpentine shape defined by bends connected by legs that each extend between a respective bend.

30. The heating element of claim 29, wherein The legs extend perpendicular to the longitudinal axis.

31. The heating element of claim 29, wherein The first side portion and the second side portion have outer edges defined by the bend portion.

32. The heating element of claim 19, wherein The circuit has a V-shape in a cross-section along a plane perpendicular to the longitudinal axis.

33. The heating element of claim 19, further comprising a shield extending over an outer surface of the tube, the shield being configured to protect the tube from physical impact.

34. The heating element of claim 19, further comprising a shield extending over an outer surface of the tube, the shield being configured to prevent microwaves used in a microwave oven from being incident on the tube.

35. The heating element of claim 19, further comprising a shield extending over the outer surface of the tube, the shield having a first portion extending along at least a portion of the length of the tube and configured to allow infrared radiation emitted by the circuit in the first direction to pass through the shield, and a second portion extending along the length of the tube and configured to block infrared radiation emitted by the circuit in the second direction from passing through.

36. The heating element of claim 35, wherein The first portion and the second portion are configured to prevent microwaves used in a microwave oven from being incident on the tube.

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